The workshop was held to collect current data on the experience with primary water stress corrosion cracking (PWSCC) of steam generator tubing and the related laboratory investigations. Thirty-two presentations were given covering field experience, correlations of laboratory data on the field, and relationship of material microstructure, stress, and environment to PWSCC. The emphasis of the workshop was more on the fundamentals associated with PWSCC yet culminated with several presentations on remedial measures.

The /sup 252/Cf neutron spectrum has been measured at high energies with a miniature ionization chamber and two different NE213 neutron detectors. The {gamma}-ray background and the main cosmic background were suppressed by applying an efficient pulse shape n/({gamma},{mu}) discrimination. On the basis of the two-dimensional spectroscopy of neutron time-of-flight and scintillation pulse height, the sliding bias method has been used to minimize experimental uncertainties. The experimental data corrected for several systematic influences confirm earlier results which show a trend similar to the NBS evaluation. However, the final spectra obtained for both neutron detectors exhibit negative deviations (up to -10%) from the NBS curve in the 6-12 MeV range. Finally, the experimental results of this work are compared with various statistical-model approaches to the /sup 252/Cf(sf) neutron spectrum. 16 refs, 16 figs, 3 tabs.

The effects of ion-implantation on the surface mechanical properties of ceramics is investigated. Changes in hardness and indentation fracture that occur in reaction-bonded silicon carbide, sialon, partially stabilized zirconia and WC are all described. These modifications are correlated to the structural changes brought about by the implantation process.

A vertical fracture type reservoir is assumed with a production well, for studying the effect of heat conduction to the response curve of the tracer using a mathematical model. With the inlet and outlet of the model located on the center axis of the fracture, flow in the fracture is always stationary. The tracer moves along the flow while dispersing mixedly. Inflow rate is 4 kg/s with an assumed inpermeable temperature boundary rock of 1 (5 m) thickness around the fracture. Tracer responses are calculated with distributed temperatures and even temperature in the fracture. The width of flow inlet does not influence tracer response. However, the height of the flow inlet and temperature distribution in the fracture greatly affect the response. (18 refs, 9 figs, 2 tabs)

Tools, equipment and weapons contaminated with radioactive, toxin, biological and/or chemical contaminants are deposited in a cleaning chamber and are sprayed with a solvent under high pressure. The solvent dislodges particulate contaminants and dissolves chemical agent contaminants and the solvent so sprayed containing both suspended and dissolved contaminants is drained to a distillation means. Within the distillation means there is a neutralizing agent which deactivates the biological and toxin contaminants and chemically oxidizes the chemical contaminants removed from the item being decontaminated in the cleaning chamber. Pure solvent vapor generated in the distillation means is condensed to a solvent tank for reuse in the spraying operation for further decontamination. Drying of the tool, equipment or weapon being decontaminated is accomplished by circulating hot, unsaturated solvent vapor through the cleaning chamber and about the item being decontaminated.

We have studied the growth and metabolism of Syntrophomonas wolfei in pure culture with crotonate as the energy source. S. wolfei grows in crotonate mineral salts medium without rumen fluid with cobalamin, thymine, lipoic acid and biotin added. However, after four to six transfers in this medium, growth ceases, indicating that another vitamin is required. The chemically defined medium allows large batches of S. wolfei to be grown for enzyme purification. All the enzymes involved in the oxidation of crotonyl-CoA to acetate have been detected. The pure culture of S. wolfei or coculture of S. wolfei grown with crotonate contain high activities of a crotonate: acetyl-CoA CoA-transferase activity. This activity is not detected in cocultures grown with butyrate. Thus, we believe that the reason why S. wolfei can now grow with crotonate is that an

alteration or mutation occurred which allows the organism to activate this crotonate. S. wolfei also makes small amounts of H{sub 2} when grown in pure culture with crotonate. A methyl viologen-dependent hydrogenase activity was found. We have also demonstrated the production of H{sub 2} from 3-hydroxybutyryl-CoA in cell-free extracts of S. wolfei by coupling H{sub 2} production to CH{sub 4} production with the addition of Methanobacterium bryantii and directly using a hydrogen electrode. These results clearly show that S. wolfei makes H{sub 2}. S. wolfei does not contain formate dehydrogenase or CO dehydrogenase activities.

An overview of the software needs of the high-energy physics community and how modern languages can meet these needs is given. Using ADA as an example, the production of readable, efficient and maintainable code is shown to be directly supported by the language, integrating concepts such as top-down design, object-oriented programming and data encapsulation as a natural part of the language rather than as foreign ideas imposed on the language. Particular attention is paid to nontraditional aspects of a language and how these can help by providing an integrated support environment for all phases of the lifetime of the software. 2 refs.

A proposed method for selecting and applying hot channel factors is presented along with some justification for these selections. The method is illustrated by example, and the sensitivity to some of the choices is examined. The uncertainty in the heat transfer coefficient is a major contributor to the reduction in thermal-hydraulic safety margins. The uncertainty introduced by the heterogeneity in the fuel is another important contributor and an area where more information may be useful in reducing this uncertainty.

Piping in light water reactor (LWR) power systems is affected by several types of environmental degradation: intergranular stress corrosion cracking (IGSCC) of austenitic stainless steel piping in boiling water reactors (BWRs) has required research, inspection, and mitigation programs that will ultimately cost several billion dollars; erosion-corrosion of carbon steel piping has been observed frequently in the secondary systems of both BWRs and pressurized water reactors (PWRs); the effect of the BWR environment can greatly diminish the design margin inherent in the ASME Section III fatigue design curves for carbon steel piping; and cast stainless steels are subject to embrittlement after extended thermal aging at reactor operating temperatures. These problems are being addressed by wide-ranging research programs in this country and abroad. The purpose of this review is to highlight some of the accomplishments of these programs and to note some of the remaining unanswered questions.

Supplement No. 12 to the Safety Evaluation Report for the application filed by Arizona Public Service Company, et al., for licenses to operate the Palo Verde Nuclear Generating Station, Units 1, 2 and 3 (Docket Nos. STN 50-528/529/530), located in Maricopa County, Arizona, has been prepared by the Office of Nuclear Reactor Regulation of the Nuclear Regulatory Commission. The purpose of this supplement is to update the Safety Evaluation Report by providing an evaluation of (1) additional information submitted by the licensee since Supplement No. 11 was issued and (2) other matters requiring staff review since Supplement No. 11 was issued, specifically those issues that required resolution before Unit 3 full power licensing.

The Coolant Inventory Monitor System for measuring the amount and the distribution of coolant in the primary system under accident conditions of a nuclear power plant is described in this report. This system is based on measuring the local void fraction of the coolant at selected points in the vessel and piping system and then estimating the coolant inventory. This report summarizes the development of the measurement instrument, the supporting tests and the development of the supporting software. Accuracies of +-2% as compared with delta pressure cells can be obtained over void fractions ranging from 0 to 90%. The system can provide local measurements of void fraction and uses probes as small as 0.015 x 1.0 x 0.3 in. (0.038 x 2.54 x 0.76 cm). Experimental test data are shown for temperatures up to 570{sup 0}F (572K). The system can be used

up to the critical point. The graphics display shows a real time display of void fraction for up to fifteen channels and gives the instantaneous as well as a running average for each channel. This instrument is believed to meet the intent of the NRC by being able to measure the amount of water above the reactor core under all types of accidents. 10 refs., 31 figs., 3 tabs.

This report summarizes the findings on Westinghouse Reactor Coolant Pump Seal Performance at the Indian Point 2 Nuclear Power Station. The study was conducted under the joint sponsorship of Consolidated Edison of New York and the US Nuclear Regulatory Commission Office of Research. The conclusions and recommendations herein are based on the review of the plant operational and maintenance data on seals, consultation with Westinghouse and Utilities, review of prior studies, and visual as well as in-depth examination of service exposed seals received from the plant. 9 refs., 28 figs., 3 tabs.

The potential for using a Forth language microprocessor to implement very high level languages (VHLLs) in Artificial Intelligence research was investigated by surveying the current state-of-the-art of VHLLs, by benchmarking several computers and microcomputers against a customized Forth Language microprocessor, and by extrapolating the results to draw conclusions about implementing expert systems on the Forth language microprocessor. 20 refs., 6 figs., 1 tab.

TORT is designed to solve very large two- or three-dimensional neutron and/or photon transport problems on a Cray or comparable computer using the method of discrete orginates. Extensive adaptability to new systems has been provided. Several flux solution procedures and acceleration methods are provided. The code can be used in stand-alone mode or under control of a driver. Problem specification requirements are similar to those of the DOT code, but are simpler and more convenient. The new zone specification format can be converted to a combinatorial geometry form for use in Monte Carlo codes. Several applications papers and a benchmark experiment relating to TORT have been produced. 70 refs., 3 figs., 9 tabs.

Since 1981, a research program has been in progress to determine the physical properties of kraft black liquors and to develop methods for reduction of data and correlation of properties with pumping conditions. The basic premise that has been used to direct the research program is that kraft black liquor behaves as a polymer solution, particularly at high solids, and that the behavior is dominated by the characteristics of the lignin present. This premise is proving to be correct, and the principles that follow from this premise are proving to be successful for data reduction and correlation. The research has been a complex program involving experimental pulping, chemical analysis, lignin separation and characterization, thermal analysis, rheological measurements, and considerable equipment and methods development. Due to the complexity of the program, the unforeseen need to expend a great deal of effort in development of experimental techniques for analysis, and the fact that our liquors proved to be unstable at high temperatures and solids, all of the original objectives could not be accomplished. However, our program has added substantially to the body of knowledge of physical properties of black liquor. Our results indicate that the goal of developing correlations for physical properties of kraft black liquor is practical and can be realized through extension of the present work.

This booklet discusses the role of TVA in the development of the forestry industry in the Tennessee Valley. Topics include the resource, managing the forests, harvesting, and marketing. (ACR)

This report covers the third quarter of calendar year 1987. The NRC licensing activity during the period of this report included the issuance of a full-power license for Beaver Valley 2 on August 14, 1987, and operating license restricted to five percent power for South Texas Unit 1 on August 21, 1987. Additional licensing delay for Shoreham is projected due to complex litigation. Also, licensing delay may occur for Comanche Peak Unit 1, because the duration of the hearing is uncertain. Although a license authorizing fuel loading and precriticality testing for Seabrook Unit 1 has been issued, there is a projected

delay for low-power licensing. Full-power licensing for Seabrook Unit 1 will be delayed due to offsite emergency preparedness issues. The length of the delay is not known at this time. With the exception of Seabrook and Shoreham, regulatory delays in this report are not impacted by the schedules for resolving off-site emergency preparedness issues.

Individual papers are processed separately for the data bases. (TEM)

The siting criteria, quality assurance, and standardized equipment and analytical methodology are addressed to insure the highest quality data for interpretive research. The national distribution of concentration and deposition for calcium, ammonium, chloride, nitrate, sulfate, and pH are shown in a series of maps. The maps show high concentrations of calcium and ammonium in the Great Plains, high concentrations of nitrate, sulfate, and hydrogen ion in the eastern states, and high concentrations of chloride along the coastal states. The primary conclusions are the greatest deposition is directly associated with the largest emission regions, and dry deposits are largely unknown, but clearly must be measured before the biochemical and geochemical cycles will be fully understood. 25 refs., 8 figs.

The concentrations of the major inorganic ions in precipitation exhibit seasonal (3-month average) excursions at eastern US sampling locations. This study extends previous work by examining intra-annual variations in concentrations for all of the major inorganic ions in both the western and eastern US. NADP/NTN data from October 1978 to March 1984 were used. Concentration ratios were calculated, where the ratio was either warm season concentration/cold season concentration or warm period concentration/cold period concentration. Seasons were 3-month intervals, while periods were 5-month intervals. The summer (warm) season was June, July, and August, while the winter (cold) season was December, January, and February. The summer (warm) period covered the 5-month interval from May through September, while the winter (cold) period covered the interval from November through March. For most of the US, the warm and cold periods approximated the growing seasons and dormant seasons, respectively. 15 refs., 16 figs., 1 tab.

In this study, estimates were made of the bias in Ca, Na, and SO{sub 4} that resulted from the collection and handling of wet deposition samples in the NADP/NTN. The geographic patterns and relative importance of this bias to deposition from precipitation are demonstrated. Wet deposition data from 1978 to 1986 are available from the NADP/NTN Coordinator's Office. Quality assurance summaries that report on various measurements of bias and precision are now becoming available. Important sources of possible bias in the NADP/NTN system include analytical measurements, laboratory handling, the sampling container, a plastic (LPE) bucket, dust that enters the collection bucket while it is in the collector, but covered during dry weather (i.e., infiltration), and field handling. 12 refs., 7 figs.

Visibility and acid rain are two phenomena that both have direct relationships to air quality. This paper explores the relationships between three data sets, with emphasis on the situations for the eastern US. This paper presents interpretation of the most current precipitation chemistry data from the National Atmospheric Deposition Program/National Trends Network (NADP/NTN), which started in the eastern US in 1978 with less than 20 sites and continues today with over 200 sites spread across the entire US. The high site density and relatively long data record make the precipitation sulfate data particularly important. Spatial and seasonal maps and tables of sulfate in precipitation are compared to literature and unpublished values for visibility and air quality sulfate. Reasonable spatial and seasonal correspondence is found between precipitation sulfate and air quality sulfate. For visibility, the spatial pattern for coastal areas is not consistent with the precipitation sulfate pattern, presumably due to the effect of relative humidity. The seasonality pattern of visibility is not consistent with that for precipitation sulfate in Illinois, but is consistent for areas to the east. 17 refs., 4 figs., 2 tabs.

The goal is to improve our ability to predict the locations and magnitudes of atmospheric wet deposition. As one portion of a broader analysis of five years of event precipitation chemistry data for central Illinois, we examined variations in ion composition and deposition with synoptic weather type to improve our scientific understanding of the chemical and physical mechanisms of scavenging and deposition of pollutants by precipitation. 8 figs., 1 tab.

This chapter summarizes the results of the back trajectory calculations for flux classes utilizing the trajectory model (the ISWS model). This analysis involved approximately 250 precipitation chemistry samples and the calculation of about 1100 back trajectories 72 hours in length. Precipitation samples have been collected routinely since September 1979 at a field site in rural east-central Illinois. Samples were collected with automated wet-only collectors of the HASL design. To monitor operations, a raingage tandem to the collectors was installed to record the precipitation amount, time of occurrence, and the open/close status (i.e., event record) of the sample collection buckets on the collectors. Data from the gage were combined with the chemical concentration measurements of samples from the collectors to compute wet-only fluxes of sulfate and nitrate. The fluxes were divided into high, middle, and low classes. 18 refs., 46 figs., 12 tabs.

The analytical chemistry laboratory continued its participation in the interlaboratory comparisons of precipitation chemical analyses sponsored by the World Meteorological Organization (WMO). In the past three years our involvement in international precipitation chemistry intercomparisons expanded to include participation in studies conducted by the Canadian Long Range Transport of Atmospheric Pollutants (LRTAP) Program and the European Monitoring and Evaluation Program (EMEP) carried out by the Norwegian Institute for Air Research. These programs provide valuable data on the comparability of chemical determinations made at geographically disperse laboratories as well as documentation of the analytical procedures that are being utilized for precipitation chemistry measurements. This data base is an important source of information when comparing chemical results from different monitoring programs. 3 refs., 4 tabs.

A rigorous internal quality assurance program has been developed to ensure that laboratory measurements are of the highest quality. As a part of this program, each sample analysis is verified by the use of an ion balance calculation. The ion balance data have been used in part to develop objective criteria for the reanalysis of samples on a routine basis. A closer examination of these data has revealed patterns in the ion ratios that are a function of sample pH, site location, and collection season. These patterns are discussed in terms of how to most effectively utilize ion balance data to verify the accuracy of laboratory measurements. The Illinois State Water Survey (ISWS) has been responsible for the chemical analyses of precipitation and dry deposition samples generated from the monitoring network. Over 50,000 wet deposition samples representing 200 sites have already been processed by the ISWS Laboratory. 5 refs., 14 figs., 2 tabs.

The two most common methods utilized and referenced for the determination of the anions Cl, NO{sub 3}, and SO{sub 4} in atmospheric samples are automated colorimetry and ion chromatography (Fung, et al., 1979). These two methods, and their associated instrumentation, were selected for an analytical comparability study because of their widespread use. Limited work by others in this field have demonstrated the comparability of these techniques for precipitation analyses. For this study, 200 randomly selected precipitation samples were chosen from the NADP/NTN network and analyzed by the Illinois State Water Survey laboratory. Samples collected during a late summer, early fall period included varied climatic and geographic regions. Statistical comparisons of data obtained from each of the methods were the major emphases of this study. Detection limits, precision, method bias, and analyte concentration values were compared. 5 refs., 3 figs., 2 tabs.

By investigating the long-term stability of the major ion species, inferential deductions may be made about the suitability of these types of samples for varied study purposes. Most ion stability studies have focused on short-term chemical changes that occur in precipitation samples. The time scale involved in these studies has varied from hours to six weeks after collection. The long-term stability of ions in solutions is an area of interest that is important if archived samples are ever used for purposes other than their original intent. An example of this instance would include the measurement of trace metals in archived wet deposition samples that were originally collected only for major ion determinations. 2 refs., 9 figs., 3 tabs.

Our goal was to formulate and prepare a reference material that could be used as a quality control check sample. The material should be NBS traceable bias and precision, be available at low cost, have ionic concentrations approximating natural rainwater, and possess long-term stability. NBS traceability was accomplished by comparing our results with the certified NBS values. Multiple measurements performed over a five month period were used to assess long-term stability. 3 refs., 10 figs., 6 tabs.

This chapter presents additional methodological and ambient data results. The ambient data results are preliminary, since additional work is needed to develop the best procedure to correct for blanks and for flow calibration. The Illinois State Water Survey (ISWS) has been involved in a major research program to investigate the precipitation scavenging of trace constituents in the atmosphere. The routine collection and analysis of event precipitation samples was begun in June 1979. A routine ambient air sampling program was included with the precipitation chemistry collection project. The field methods and laboratory procedures for the ambient aerosol sampling were chosen to be consistent with the goals and procedures for the precipitation chemistry sampling. The unique features of the Bondville daily aerosol data set are that it is a rather long daily record (starting in May 1977); it includes data for Ca{sup 2+}, Mg{sup 2+}, Na{sup +}, and K{sup +} which are often neglected in other studies; and the method includes an extraction step designed to simulate dissolution of particles in raindrops (i.e., a "soluble" extraction rather than a total extraction).

In this chapter we present aerosol and precipitation chemistry data for SO{sub 4}{sup 2-}, Ca{sup 2+}, Mg{sup 2+}, K{sup +}, and Na{sup +}. These data are summarized by season from measurements made at the Bondville Field Site. Of the five species, only SO{sub 4} has both particle and gaseous species to consider. Only recently has SO{sub 2}, the primary gaseous sulfur component, been measured at the site (as part of a dry deposition project), so for this chapter no SO{sub 2} data are presented. 5 tabs.

We have developed a computer program to calculate a single representative statistic for each state, given a variable that is measured at a limited number of sites across the United States. Our program is called AREA for ARea Estimating Algorithm. 7 refs., 5 figs., 4 tabs.

Concerns surrounding air and precipitation quality have led to frequent use of trajectory models in the past decade in an attempt to relate natural and anthropogenic sources of various constituents to those observed in the media in question. These trajectory models range in complexity from efforts such as using the output of a prognostic, mesoscale, numerical weather prediction model, to those using observed rawinsonde data in a relatively simple diagnostic model. An example of the latter is the Air Resources Laboratories Atmospheric Transport and Dispersion (ARL-ATAD) Model of Heffter (1980) (hereafter referred to as the ATAD model). The ATAD model was designed to calculate large numbers of boundary layer trajectories from several origins in an economical manner. The goal of the analyses and the type of data led to the development of a new trajectory model (hereafter referred to as the ISWS model). This chapter includes an overview of some recent work with the ATAD model; a description of the ATAD model; sources of error in trajectory calculations; a description of the ISWS model; comparison of the ATAD and ISWS models; and conclusions. 28 refs., 13 figs., 1 tab.

Dry bucket samples were collected at all National Atmospheric Deposition Program (NADP) sites from the network's inception in mid-1978 until June 1984, when the collection of the dry samples became optional. A one-month intercomparison of dry deposition monitoring and measurement methods at an Illinois grassland site included a detailed comparison of results for sulfur dry deposition to buckets and other surrogate surfaces, as well as fluxes measured by micrometeorological techniques (Dolske and Gatz, 1984). Sulfur dry deposition fluxes measured by the bucket collectors were consistently the highest of those measured by the various surrogate surfaces. This work analyzes a portion of the existing dry bucket data set to determine the effect of various screening criteria on the frequency distribution of measured dry fluxes of each measured ion. 15 refs., 8 figs., 2 tabs.

This paper briefly details the physical and climatological characteristics and the history of site development. The Illinois State Water Survey (ISWS) Atmospheric Chemistry Section has carried out studies involving the chemical and physical components of wet and dry deposition and aerosol materials at the field site since February 1978. These studies have included elaborate collection and analysis procedures and substantial research in the areas of sampling development and monitoring. The changing requirements of resource decision makers require information that can only be gained at sites which contain historical records regarding all of these activities. 6 refs., 2 figs.

The goal of this research was to produce 8% efficient solar cells deposited at a rate of 15 angstroms/second or greater. Intrinsic material quality was evaluated using dark conductivity, photoconductivity, surface photovoltage (SPV), and space charge limited currents (SCLC). Finished solar cells were analyzed using uncorrected quantum yield and uncorrected quantum yield under 1 volt reverse bias. Efficiencies were measured under simulated global AM1.5 illumination. A peak efficiency of 7.6% was achieved where the intrinsic layer was deposited at 15 angstroms/second.

This research concerns the properties of a-Si:H films and solar cells prepared by mercury-sensitized photochemical vapor deposition (photo-CVD) of silane and disilane. It represents an outgrowth of earlier work on thermal CVD in which disilane was decomposed by heat alone. In the photo-CVD technique the enrgy source for decomposition is a low pressure mercury lamp. Amorphous silicon films prepared by photo-CVD are superior to thermal CVD films by virtue of having a higher photoconductivity and a lower density of defects such as dangling bonds. While the conversion efficiency of photo-CVD solar cells has not yet equalled the best glow discharge (GD) cells, it appears that photo-CVD cells are more resistant to light induced degradation.

The chemical vapor deposition (CVD) of hydrogenated amorphous silicon (a-Si:H) films using the thermal decomposition of disilane and polysilanes in an atmospheric pressure gas flow system has been under investigation as an alternative to the flow discharge technique. The advantages of the atmospheric pressure CVD, such as the ease of operation, higher deposition rates of a-Si:H films, and the absence of charged particle bombardment, have stimulated further investigations of this process. While the electronic properties of early CVD a-Si:H films are inferior to those of glow discharge films, continued optimization of the deposition process has improved significantly the electronic properties of CVD a-Si:H films. In this work, a-Si:H films have been deposited on Corning 7059 glass and other substrates by the thermal decomposition of disilane in a helium or a hydrogen flow. Under the same deposition conditions, the deposition rate of a-Si:H in He is significantly higher than that in H{sub 2}. Also, a-Si:H films deposited in He have been found to have better structural and electronic properties and lower defect densities than those deposited in H{sub 2}. Further, a post deposition treatment of a-Si:H films deposited in He has been shown to reduce the defect density to (2 to 4) x 10{sup 15} cm{sup -3}, as measured by photothermal deflection spectroscopy. The experimental procedures and results are summarized in this paper.

ARCO Solar has been pursuing the development of thin films as the next generation of photovoltaics to substantially displace the present dominant technology based upon crystalline silicon. We have chosen two thin film materials, namely, thin film Si:H or a-Si (TFS) and copper indium diselenide (CIS). These have band gaps of 1.7 and 1.0 eV, respectively, and offer opportunities as stand-alone devices with high voltage or high current per unit area, respectively, as well as combined to form high efficiency tandems. In this paper a review of the development of these devices will be presented. The discussion will begin with products that have been introduced and proceed through products presently being introduced to predictions of future product expectations and progress made toward those expectations.

This second volume of the Proceedings of the 1986 Workshop on Laser Propulsion, sponsored by SDIO and DARPA and held at the Lawrence Livermore National Laboratory, 7-18 July 1986, consists of papers contributed by Workshop attendees. While only a fraction of those present at the Workshop are represented here, these papers give a cross section of current ideas in the field. In particular, "Laser Thermal Propulsion" and "CW Laser Propulsion" give an overview of ongoing work on propulsion by CW lasers, while "Laser Propulsion to Earth Orbit..." presents a concept for pulsed laser propulsion that is the focus of considerable new research. "One-Dimensional Modelling of a Two-Pulse LSD Thruster" and "Trajectory Simulation for Laser Launching" describe some of this research in embryo form. Laser propulsion lends itself to some unique applications, some of which are discussed in the paper "Strategic Defense Applications of Ground-Based Laser Propulsion." "Laser Weapon Target Practice with Gee-Whiz Targets" describes a particularly spectacular application of propulsion by photon momentum. Finally, some engineering possibilities for advanced laser-propelled vehicles are described in "The 'Mercury Lightcraft' Concept." Individual papers have been cataloged separately.

The development of thruster technology has not been vigorously pursued, and such work as has been carried out seems more adapted to the task of changing the orbit of a satellite (which needs much less laser power). The development of thruster technology for earth-to-orbit applications has not been funded, and, therefore, thruster technology remains the chief technical unknown in assessing the possible importance of laser propulsion to earth orbit. An approach to this problem is offered below. Perhaps the most important change that has occurred in recent years is the perceived need to transport thousands of tons annually to LEO. Part of this payload will be large numbers of relatively small units. A second part (e.g., fluids or other bulk materials) can be assembled in orbit. A third part is better launched in units weighing many tons. This paper assesses what is needed to realize a practical laser propulsion system for those payloads that can be launched as large numbers of relatively small units. While past experience clearly demonstrates the necessity of extreme caution in predicting the costs of space-transportation systems, we will give reasons for believing that, for some applications, such a system could be considerably cheaper than chemical rockets.

Herein is recommended an alternative manned transatmospheric vehicle based on the Mercury capsule and scaled to a maximum laser power level of 1 GW.

This paper contains a technical discussion and research proposal to identify the physical processes that are of importance for laser sustained argon and hydrogen plasmas of large size to incorporate those processes into improved computational models. (LSP)

Recent experimental and analytical studies at the University of Illinois and the University of Tennessee indicate that CW laser propulsion is an entirely feasible form of advanced rocket propulsion that can produce high specific impulses at high thermal efficiencies. These studies have clearly defined the physics of the CW process, have failed to uncover any serious feasibility problems, and have paved the way for additional scaling studies at higher laser powers. This report discusses the current state of the art of CW-laser propulsion research through a full description of ongoing research at the

University of Illinois. It also discusses the implications of these findings and indicates the types of propulsion missions for which CW laser propulsion is best suited. Two possible designs for earth-launch CW thrusters are also presented. Finally, the additional near-term research that is needed to fully verify the feasibility of high-power CW-laser propulsion is discussed.

It is proposed that small, lightweight, highly reflecting targets be deployed outside the atmosphere by a sounding rocket and used to test ground-based laser weapon systems. The photon pressure from the laser beam would drive the targets outward at high accelerations to reach extremely high terminal velocities - the fast objects in the solar system. The targets would test the system pointing, tracking, and focusing subsystems in a nondestructive manner that would blunt criticism of the tests. Since the light reflected by the targets could be seen from the ground, the tests would allow public viewing and participation from anywhere in the continental United States.

Ground-based laser propulsion can provide a cheap means of launching small payloads to earth orbit. This technology may provide important advantages for some strategic-defense applications. Potential missions include launch of bulk cargo to an orbital facility, maintenance of satellites in very low orbits, boost-phase missile intercept, and quick-look reconnaissance.

Laser propulsion may allow the construction of thrusters with specific impulses variable in flight from near zero to over 1000 seconds. The performance of laser-propelled vehicles launched from earth to orbit will be constrained by properties of the laser, the propagation path, and the thruster itself. The optimum trajectories for launching laser-propelled vehicles by using a ground-based laser may thus differ considerably from those for conventional rockets. We discuss how the components of a launch system affect its performance and present initial results from a trajectory simulator for such vehicles that allows us to model many features of a laser launch. With a thruster efficiency of 40%, payloads of about 1500 kg/GW of laser power can be launched from the ground to low earth orbit (LEO); high specific impulses (>800 s) may be desirable even for the early low-velocity part of the trajectory.

There is no doubt that thrust can be generated by direct irradiation of a surface by a pulsed laser beam; the impulse so developed has been extensively studied as a means of destroying targets with lasers. However, while the same basic principle can be applied to rocket propulsion, the details will differ. Unfortunately, when a surface is directly irradiated by a pulsed laser, the amount of material blown off is governed by its strength and vaporization energy. This ejecta generally has too wide an energy range and too low a mean velocity for use in an efficient surface-to-orbit laser rocket. A higher and more controllable exhaust velocity can be attained by a two-step process; one first emplaces the desired amount of propellant as a gas layer above the surface, and then deposits the laser energy directly in this atmosphere. Because the amount of propellant used is no longer determined by the deposited laser energy, this method permits the exhaust velocity to be chosen separately; the less gas used, the higher its speed. To use this technique, a way is needed to emplace the gas layer, and have a strong enough absorption mechanism so that the incident laser flux deposits in the atmosphere before reaching the underlying surface. The gas layer can be formed in several ways; one option employs transpiration of a liquid through a porous plate, while another uses a laser prepulse to ablate the desired amount of gas from a solid propellant surface. This report concentrates on modelling the post-emplacement events, i.e., absorption of laser light by the gas, and its subsequent hydrodynamic motion.

Transport simulations of the present designs for the INTOR and TIBER ignition devices predict that broad sawtooth oscillations will appear in these experiments. As was noted previously in studies of the Compact Ignition Tokamak, the primary effect of the oscillations is to reduce fusion power production on the average through profile flattening. Due to the disparate time scales for energy and current diffusion between sawtooth crashes, the simulations also produce peaked pressure profiles over a large low shear region inside the q = 1

surface (q is the safety factor). Pressure-driven modes will likely be unstable in this case. 5 figs., 2 tabs.

Aim of the work was to develop a highly spectral selective absorber surface based on cobalt oxide, which is thermally stable up to 500{sup 0}C both in air and in vacuum, with a relatively high corrosion resistance and which is attractive for economic application. Two types of cobalt oxide coatings have been developed with different properties as to spectral selectively, thermal stability, corrosion resistance and production processes: (1) Co/Fe (III) oxide on Ni, produced by flame or furnace oxidation of electroplated Co/Fe(III) on bright plated Ni. (2) Co/Mo oxide on Ni, produced by electrochemical oxidation of electroplated Co/Mo on bright plated Ni. Other alloying elements, such as W and Cr, were investigated to improve the durability. A diffusion barrier layer with Pd and Cr in between the substrate and the cobalt coating did not significantly improve the stability. Some outdoor testing of the above mentioned surfaces supplied on different collector types has given results on stagnation temperatures as could be expected with similar selective surfaces of other origin. 17 refs., 42 figs., 41 tabs.

Objective of the research program was to develop a pilot-plant facility to produce glass-ceramic ('Silceram') by a novel process. In this, a silicate melt was converted to a fine-grained pore-free ceramic during a controlled-cooling heat treatment, removing the need for reheating. The new heat-treatment program offers a substantial saving in thermal energy. The new material had superior mechanical properties. These were extensively studied in laboratory tests, as functions of microstructure and chemical composition. The crystal size of the major silicate phase was about 2 {mu}m and the porosity was close to zero. The high strength and hardness are associated with excellent resistance to erosion by fluid-borne particle. 9 figs., 13 tabs.

Aim of this project was to study the replacement of classic heating processes by microwave heating. A knowledge of the microwave and thermal parameters of the materials to be treated was needed for computer simulation and optimization of the process. Two methods have been developed to measure the dielectric properties of potential products. A computer program was implemented to simulate microwave adsorption in multilayered media and to predict the resulting temperature profiles. Automatic and contactless temperature measurement techniques have been studied to allow a higher degree of process control. Three different microwave systems were constructed and fully tested. Finally, attention was paid to the economic aspects. 7 refs., 7 figs.

A dense random packed model of an amorphous alloy was used to calculate the total and partial reduced radial distribution functions, the Bhathia-Thorton number-concentration fluctuations, and the number-concentration interference functions. The model was applied to amorphous Ni{sub 35}Ti{sub 65} using atomic radii of 1.10 and 1.58 A{sup -1} for nickel and zirconium, respectively. Chemical short-range order was included in the model by permuting nickel-zirconium nearest-neighbors atoms pairs in response to a decrease in the alloy's enthalpy. The permutations were found to decrease in the Warren-Cowley order parameter from zero to -0.38. The increase in chemical short range order is accompanied by the appearance of a peak in the partial interference function I/sub Ni-Ni/(K) at K = 1.9 A{sup -1}. The increase in chemical short range order and the prepeak in I/sub Ni-Ni/(K) are tentatively attributed to the formation of double tetrahedra with three zirconium atoms at the base and two nickel atoms at the apexes. 18 refs., 5 figs.

This investigation involved the (1 x 2) reconstruction of the Ni(110) surface induced by the adsorption of deuterium in the temperature range from 165-175 K. The (1 x 2) phase of Ni(110), which is produced upon adsorption of either hydrogen or deuterium at or near saturation coverage, is known to involve reconstruction of the substrate, but there has been some controversy as to whether the surface structure involves missing rows or paired rows. Purpose of this investigation was to determine if the atomic structure of the reconstructed surface could be identified by field ion microscopy. 8 refs., 2 figs.

A preamplifier having 500 electrons noise (rms) has been developed for the detection and location of single electrons in a CRID detector at the SLD. A single channel contains preamp, RC-CR shaper, gain adjustment, driver, and calibration circuitry. Noise and linearity measurements are presented.

The author, a novice user of the CERN detector simulation package GEANT, offers a very brief summary of some of the strengths and weaknesses of the program, along with some indications of what must be done to implement a useful detector simulation for the SSC energy scale.

Single crystals of {alpha}-Al{sub 2}O{sub 3} were implanted with {sup 57}Fe{sup +} at room temperature to fluence ranging from 10{sup 16} to 10{sup 17} ions/cm{sup 2}. The damage in the implanted zone and the valence states and local environment of implanted ions were studied by transmission electron microscopy, Rutherford backscattering-channeling, and conversion electron Moessbauer spectroscopy. The implanted iron was distributed among the three charge states Fe{sup 2+}, Fe{sup 3+}, and Fe{sup 0} (metallic clusters) with the relative amount of each varying with concentration of implanted iron. 16 refs., 3 figs., 1 tab.

A study of the characteristics and the energy needs of farms, agro-industries and forestry organizations has been carried out for the Tuscany region of Italy. Data on biomass resources are given, together with some data on the potential of energy crops and harvesting costs. The socio-economic benefits, which derive from a wide regional penetration of the biomass pyrolytic conversion technology, are evaluated. 7 refs., 22 tabs.

The design of an automotive Stirling engine that achieves the superior fuel economy potential of the Stirling cycle is described. As the culmination of a 9-yr development program, this engine, designated the Mod II, also nullifies arguments that Stirling engines are heavy, expensive, unreliable, and demonstrate poor performance. Installed in a General Motors 1985 Chevrolet Celebrity car, this engine has a predicted combined fuel economy on unleaded gasoline of 17.5 km/L (41 mi/gal) - a value 50% above the current vehicle fleet average. The Mod II Stirling engine is a four-cylinder V-drive design with a single crankshaft. The engine is also equipped with all the controls and auxiliaries necessary for automotive operation. 35 figs.

This booklet was prepared for the 50th anniversary of medical and biological research at the Donner Laboratory and the Lawrence Berkeley Laboratory of the University of California. The intent is to present historical facts and to highlight important facets of fifty years of accomplishments in medical and biological sciences. A list of selected scientific publications from 1937 to 1960 is included to demonstrate the character and lasting importance of early pioneering work. The organizational concept is to show the research themes starting with the history, then discoveries of medically important radionuclides, then the use of accelerated charged particles in therapy, next human physiology studies then sequentially studies of biology from tissues to macromolecules; and finally studies of the genetic code. 83 figs.

Our work has established that the rate of the Fe(II)-dependent reduction of rusticyanin is far too slow to be physiologically significant; that the Fe(II)-dependent reduction of rusticyanin shows no anion specificity; and that electron transfer from Fe(II) to rusticyanin may actually be catalyzed by a cytochrome c. These observations are helping to redefine the roles from respiratory chain of T. ferrooxidans. The kinetic methodology developed here provides a means of determining the values of the Km and Vmax for a nonchromogenic substrate by exploiting the effects of the nonchromogenic substrate on the enzymatic transformation of a corresponding chromogenic substrate. These procedures may be applied to any enzyme which catalyzes a strongly exergonic reaction with no appreciable product inhibition. It is anticipated that the kinetic procedure developed here could enjoy a widespread application to problems in biochemistry. On a more practical note, inadequate means of obtaining high cell densities have hindered the progress in both basic and applied research concerning T.

ferrooxidans. The preliminary observations that the cell yield of iron-oxidizing bacteria may be dramatically increased as a result of electrolysis holds great promise for both basic and applied research involving this organism. 3 figs.

The paper describes the role of the National Physical Laboratory (NPL) in connection with the safe use of ionising radiation. The NPL provides a range of calibration services which allow instruments used for dosimetry measurements to be compared with primary standards.

This is a symposium articles in the NEDO NEWS (Aug, 1986). Main articles described are as follows: (1) Technical development of fuel grade alcohol. (2) Development of methane gas production unit with a composite high performance separation membrane. (3) Demonstration test on conversion of oil power plant to methanol power plant. (4) Promotion survey on the commercialization of biomass technology. (5) Execution agreement on IEA - fuel grade alcohol for automobile.(11 figs, 1 tab)

The paper discusses progress in the system design of the Tiber-II tokamak. In particular, topics discussed are neutronics analysis; thermal hydraulics analysis; activation analysis; LOCA and LOFA analysis; D/He-3 operation on Tiber-II; and a scoping design study of a D/He Tandem mirror reactor. (LSP)

The effective electrophysical properties of moderately concentrated disperse systems consisting of a continuous uniform phase with spherical particles distributed in it have been considered by the methods of ensemble averaging together with the methods of the self-consistent field theory. In contrast to the former investigations, the assumption that Maxwell's equations are quasistationary, which is not valid for high-frequency electromagnetic fields, was not utilized here. In order to simplify the investigation, the presence of foreign and surface charges, as well as the effective surface conductivity of the particles, which is significant at sufficiently low frequencies, were neglected. The results obtained make it possible to calculate the effective dielectric constant and the conductivity of systems whose phases have been dielectric and conducting properties and to evaluate the dispersion and the attenuation of waves in such systems.

A theory has been developed for the interaction of ideally polarizable particles and biological cells in a steady (dc) electric field. The proposed approach differs from the classical dipole-dipole theory in that the carrier of the interaction is not the electric field, but rather the hydrodynamic field. For this reason, the indicated interaction decreases with increasing distance between particles at a considerably lower rate, similar to Coulomb interaction.

Thermodynamic perturbation theory has been used to describe the structure of a fluid consisting of linear dipolar-quadrupolar molecules in an external electric field near an interface. The general case in which the field is directed at an arbitrary angle to the interface has been considered. Expressions for the complete system of first- and second-order parameters describing the orientational ordering of the molecules in the nonuniform region have been derived.

The goal set for this work was a generalization of the theory of pair interaction of disperse particles in an electric field. The particles in the long-range interaction zone move relative to each other, entrained by flows of the dispersion medium. This motion of the liquid is caused by polarization electroosmotic flows on the particle surfaces. A quantitative description of this motion has shown that when it is taken into account, the present concepts of the stability of dispersions in an electric field may be modified substantially. The energy of interaction that is characteristic for this motion decreases in inverse proportion to the first power of the distance between particles.

A theory has been constructed for the hydrodynamic interaction of disperse dielectric particles in a stationary electric field, in which double layer (DL) polarization is taken into account in the most complete manner. The accounting

for nonlinear polarization of the DL leads to qualitative changes in the theory of hydrodynamic interaction. This is related to electroosmotic flows due to the electric field of the nonlinear bulk charge of the polarized DL. The problem of the trajectory of relative motion of the particles has been solved. Basic relationships in the direction of this motion have been found.

The authors report here the resonance Raman spectra of octopus rhodopsin and its photoproducts, bathorhodopsin and acid metarhodopsin. These studies were undertaken in order to make comparisons with the well-studied bovine pigments, so as to understand the similarities and the differences in pigment structure and photochemical processes between vertebrates and invertebrates. The flow method was used to obtain the Raman spectrum of rhodopsin at 13 {sup 0}C. The bathorhodopsin spectrum was obtained by computer subtraction of the spectra containing different photostationary mixtures of rhodopsin, isorhodopsin, hypsorhodopsin, and bathorhodopsin, obtained at 12 K using the pump-probe technique and from measurements at 80 K. Like their bovine counterparts, the Schiff base vibrational mode appears at {similar_to}1660 cm{sup -1} in octopus rhodopsin and the photoproducts, bathorhodopsin and acid metarhodopsin, suggesting a proteonated Schiff base linkage between the chromophore and the protein. Differences between the Raman spectra of octopus rhodopsin and bathorhodopsin indicate that the formation of bathorhodopsin is associated with chromophore isomerization. This inference is substantiated by the chromophore chemical extraction data which show that, like the bovine system, octopus rhodopsin is an 11-cis pigment, while the photoproducts contain an all-trans pigment, in agreement with the previous work. The octopus rhodopsin and bathorhodopsin spectra show marked differences from their bovine counterparts in other respects, however. The differences are most dramatic in the structure-sensitive fingerprint and the HOOP regions. Thus, it appears that although the two species differ in the specific nature of the chromophore-protein interactions, the general process of visual transduction is the same.

Accompanying the phototransformation of native 124-kilodalton (kDa) oat phytochrome from red-absorbing form (Pr) to far-red-absorbing form (Pfr), there is a photoreversible change in circular dichroism (CD) in the far-UV region indicative of a 3% increase in {alpha}-helical folding of apoprotein. To elucidate the conformational change involved in the phytochrome phototransformation, several monoclonal antibodies have been used as epitope-specific probes. Monoclonal antibody oat-25 suppressed the photoreversible CD spectral change using phytochrome with an A{sub 666}/A{sub 280} as Pr of 1.13. Monoclonal antibodies oat-22, oat-13, and oat-31 did not significantly affect the CD spectral change of phytochrome. Oat-25 requires an epitope near the N-terminus of phytochrome. Oat-22, oat-13, and oat-31 recognize epitopes on the N-terminus, chromophore-containing half of phytochrome, albeit further removed from the N-terminus than that recognized by oat-25. Interestingly, oat-13 and oat-31 did, however, induce a time-dependent decrease in the far-UV CD, apparently due to aggregation of phytochrome (both Pr and Pfr forms). Monoclonal antibodies oat-26 and oat-28, which recognize epitopes on the C-terminus half of phytochrome, also did not suppress the photoreversible CD change, although oat-26 and oat-28 slightly inhibited it. The photoreversible CD spectral change can also be inhibited by sodium borohydride, which bleaches the chromophore by reducing it, and by tetranitromethane, which oxidizes the chromophore of phytochrome. Although explanations of these results based on indirect interactions between the chromophore and the N-terminus segment are possible, the authors propose that an additional {alpha}-helical folding of the Pfr form of the phytochrome may result from a photoreversible interaction between the Pfr form of the chromophore and the N-terminus segment.

Limited chemical bromination of poly[r(C-G)] (32% br{sup 8}G, 26% br{sup 5}C) results in partial modification of guanine C8 and cytosine C5, producing a mixture of A- and Z-RNA forms. The Z conformation in the brominated polynucleotide is stabilized at much lower ionic strength than in the unmodified polynucleotide. Raising the ionic strength to 6 M NaBr or NaClO{sub 4} results in a transition in Br-poly[r(C-G)] to a Z-RNA (Z/sub R/) conformation as judged

by CD spectroscopy. {sup 1}H NMR data demonstrate a 1/1 mixture of A- and Z-RNAs in 110 mM NaBr buffer at 37{sup 0}C. Nuclear Overhauser effect (NOE) experiments permit complete assignments of GH8, CH6, CH5, GH1', AND CH1' resonances in both the A- and Z-forms. The NMR results indicate that unbrominated guanine residues undergo transition to the syn conformation (Z-form). Raman scattering data are consistent with a mixture of A- and Z-RNAs in 110 mM NaCl buffer at 37 {sup 0}C. {sup 31}P NMR spectra show six to eight resonances spread over a 1.8 ppm range whose chemical shifts are also consistent with an equilibrium mixture of A- and Z-RNAs. Radioimmunoassay and nitrocellulose filter binding competition experiments were performed to determine the extent of recognition of Br-poly[r(C-G)] by anti-Z-DNA antibodies. Competition RIA experiments verify the presence of a Z-DNA-like determinant in left-handed Br-poly[r(C-G)] at physiological NaCl concentration. In summary, these spectroscopic and immunochemical studies demonstrate that under conditions of conformational stress (i.e., containing brominated nucleosides) left-handed Z-RNA is stable and is specifically recognized by proteins at physiological temperature and ionic strength.

Groups of male B6C3F1 mice were exposed to ambient air or to gaseous 1,3-butadiene (BD) at 6.25, 62.5, and 625 ppm for 10 exposure days. Exposure to BD induced in bone marrow: 1) a significant increase in the frequency of chromosomal aberrations (CA); 2) a significant elevation in the frequency of sister chromatid exchanges (SCE); 3) a significant lengthening of the average generation time (AGT); 4) a significant depression in the mitotic index (MI): and, as measured in the peripheral blood, 5) a significant increase in the proportion of circulating polychromatic erythrocytes (% PCE), and 6) a significant increase in the level of micronucleated PCE (MN-PCE) and micronucleated normochromatic erythrocytes (MN-NCE). The most sensitive indicator of genotoxic damage was the frequency of SCE, followed by MN-PCE levels, and then by CA and MN-NCE frequencies. The most sensitive measure of cytotoxic damage was AGT followed by % PCE and then my MI. The extent of concordance ranged from a very good correlation between the induction of MN-PCE and the induction of SCE to the lack of a significant correlation between the depression in the MI and any other endpoint.

Experiments were done in {alpha}-chloralose-anesthetized, paralyzed and artificially ventilated cats with vagus, cervical sympathetic, aortic depressor, and carotid sinus nerves cut bilaterally to investigate the effect of afferent renal nerve (ARN) stimulation on circulating levels of vasopressin (AVP). Electrical stimulation of ARN elicited a pressor response that had two components, a primary (1{sup 0}) component locked in time with the stimulus and a secondary (2{sup 0}) component that had a long onset latency and that outlasted the stimulation period. The 1{sup 0} and 2{sup 0} components of the pressor response were largest at stimulation frequencies of 30 and 40 Hz, respectively. Autonomic blockage with hexamethonium bromide and atropine methylbromide abolished the 1{sup 0} component. Administration of the vasopressin V{sub 1}-vascular receptor antagonist d(CH{sub 2}){sub 5} VAVP during autonomic blockade abolished the 2{sup 0}C component. Plasma concentrations of AVP measured by radioimmunoassay increased from control levels of 5.2 +/- 0.9 to 53.6 +/- 18.6 pg/ml during a 5-min period of stimulation of ARN. Plasma AVP levels measured 20-40 min after simulation were not significantly different from control values. These data demonstrate that sensory information originating in the kidney alters the release of vasopressin from the neurohypophysis and suggest that ARN are an important component of the neural circuitry involved in homeostatic mechanisms controlling arterial pressure.

The authors report nascent OD(X{sup 2}II) rotational, vibrational, spin-orbit, and {Lambda}doublet excitations from reactions of deuterium atoms with CO{sub 2}. D atoms are produced by the 193-nm photolysis of DBr (h nu - D{sub 0} = 244 kJ mol{sup -1}) (i) within a weakly bonded CO{sub 2}DBr complex, and (ii) under 300 K single-collision bulk conditions. The differences between the resulting OD distributions are modest, and the present results are similar to those of the analogous H + CO{sub 2} system.

Reactions of D atoms with OCS were studied by 193-nm pulsed laser photolysis of DBr as a nearly monoenergetic D-atom source. Nascent OD(X{sup 2}II) and SD(X{sup 2}II) rotational, vibrational, spin-orbit, and {Lambda}doublet populations were obtained under single-collision bulk conditions at 300 K. The SD channel is favored energetically ({Delta}H = -43 +/- 13 and 230 +/- 13 kJ mol{sup -1} for the SD and OD channels, respectively) and is the dominant pathway ([SD]/[OD] = 5 +/- 2). Nascent OD(X{sup 2}II) products were also obtained from a precursor geometry limited (PGL) reaction by using the weakly bound van der Waals complex SCO-DBr. The OD(X{sup 2}II) rotational distributions are the same for both bulk and PGL conditions and can be reproduced by using a statistical model. Due to experimental difficulties, SD(X{sup 2}II) distributions could not be obtained under PGL conditions. The SD(X{sup 2}II) distribution obtained under bulk conditions is very nonstatistical, suggesting that this species is not formed via a long-lived DSCO intermediate complex in which vibrational energy is randomized.

Three approaches aimed at avoiding major accidents caused by human errors are discussed - improving the standard of operations so that errors are not made, using inherently safe reactors where human or mechanical error is not so important, and adding controls and safety systems such that human error is not allowed to lead to a dangerous situation. The first point considered is improving the standards of operators. An international version of the US INPO (Institute of Nuclear Power Operations) under the IAEA is suggested but not really seen as a realistic possibility. Inherently safe reactor designs are considered but no one design seems to provide all the features desired. Extra safety engineering has made reactor construction expensive and a cautious, gradual approach is recommended. The best hope of improving the safety and economic performance of nuclear power plants is the fear of the nuclear industry if it realised how close to extinction it actually is. (U.K.).

The paper concerns a one day conference on nuclear power organised by the Centre for Science Studies and Science Policy, Lancaster, April 1986. Following the Chernobyl reactor accident, the conference concentrated on public confidence in nuclear power. Causes of lack of public confidence, public perceptions of risk, and the effect of Chernobyl in the United Kingdom, were all discussed. A Select Committee on the Environment examined the problems of radioactive waste disposal. (U.K.).

Public inquiries into controversial development proposals have themselves become increasing controversial in recent years. Despite their increasing length and cost, such proceedings remain part of the administrative process - the Inspector's report serving to 'inform the minister's mind'. This paper examines certain features of the Sizewell B Inquiry and draws attention to the ability of the applicants to respond to criticisms raised at the hearings through various forms of institutional adaptation. Changes to the Central Electricity Generating Board's case on the organization of project management, to the management of the nuclear site licensing process, and to provisions for future nuclear reactor choice are highlighted. Significantly, each of these areas had been the subject of particular investigations undertaken at the behest of the inquiry Inspector. The paper concludes by raising a number of questions concerning the implications of this singularly interactive process.

Following the reactor accident at Chernobyl a moratorium has been put on the construction of reactors in Yugoslavia. Four regional utilities were to have cooperated on a nuclear programme which would have provided power for industrial expansion in Yugoslavia. There had already been public opposition to the nuclear programme but the Chernobyl accident brought renewed protests. The generation of electricity in Yugoslavia is examined. As well as providing relatively cheap electricity, it had been hoped that the nuclear engineering expertise could be used elsewhere in domestic or export markets. Now, it seems the increased energy production wanted by the Federal Government will have to be met by other means. Inter-regional cooperation will be necessary to achieve this.

The paper examines nuclear power and alternative energy sources in Sweden, following the Chernobyl reactor accident. Electricity demands, nuclear power plants, hydroelectricity, pollution, natural gas, and the phasing out of nuclear power, are all briefly discussed. (U.K.).

Results are presented of a survey on the views of members of the public who live and work in the Sellafield area, conducted in April 1984. The questions in the survey concerned: opinions of British Nuclear Fuels Ltd., (BNFL) as a local company, worries about radiation levels around Sellafield, reliability of sources of information about Sellafield, and the participation of local people in the Sellafield debate. The results do not reflect any possible changes of attitude following the 1983 incidents at BNFL's plant.

UK Nirex has announced four sites which it wishes to assess for the disposal of low-level and short-lived intermediate-level radioactive wastes. There is local opposition at all four of the potential sites. (U.K.).

Joseph Fischer, a Green Party Politician and extreme opponent of nuclear power, has been appointed environment minister in the German province of Hesse. The possible effects on the local nuclear industry are discussed. (U.K.).

Public attitudes towards environmental issues depends on the information that the public receive and the ability of the public to distinguish between fact and fiction. It is the responsibility of the media and environmental lobbies to put across the facts in a responsible and accurate way. Examples are given of how environmental issues, such as acid rain, radioactive effluents etc., are misrepresented by the media and of undesirable tactics used by environmental lobbies.

This report from the Committee of Privileges, gives the background information concerning the leak, in The Times newspaper of December 16th, 1985, of the draft report of the Environment Committee on Radioactive Waste. It then presents the minutes of evidence taken before the Committee of Privileges following the examination of the witnesses, the Editor of The Times, and a lobby reporter. (UK.

The factors that have changed public attitudes towards the use of nuclear power are reviewed. These are seen as the link between nuclear weapons and nuclear power, radiation leaks and reactor accidents and the uneconomic nature of nuclear power. These aspects have resulted in the growth of the anti-nuclear movement. The strength of the nuclear lobby and the trades unions are considered. A programme for action to end the use of nuclear power in the UK is outlined. It is hoped that a major nuclear accident will not provide the final argument. (U.K.).

A review is presented of some of the activities of the Scottish Campaign to Resist the Atomic Menace (SCRAM) during the first decade, concerning: Torness nuclear power plant; uranium imports; nuclear waste disposal; nuclear weapons; Sizewell nuclear power plant; nuclear power; Dounreay nuclear facility. (U.K.).

An experimental sample was prepared by adding boron carbide powder (0 - 50 wt%) to natural graphite powder, and 30 g of this mixture being further pulverized for 30 min. This sample was then burned, by means of a high frequency induction furnace, at 19.6 MPa, 1400 - 2300 `C, and 60 min. This burned product was measured for X-ray parameter of natural graphite content in the product, using Cuk {alpha} ray according to a standard GaKushin method. Raman spectrum was measured for a part of the sample. The result showed that an amount of boron carbide added greatly affected the values of natural graphite, d(002) and d(110) at constant pressure of 19.6 MPa and at higher temperature than 2000 `C; shape of d(110) diffraction diagram was not almost affected, although the shape of d(006) diffraction diagram at high angle was significantly affected. (5 figs, 6 refs)

In this study equilibrium segregation was measured by x-ray microanalysis in an AEM and related to boundary character and structure. Equilibrium segregation of

antimony in an austenitic stainless steel was investigated by x-ray microanalysis. Fractional monolayer coverages of antimony were detected at grain boundaries, as well as nickel enrichment and chromium depletion. Equilibrium segregation depends on boundary character. The measured apparent compositions are corrected for the relative spatial extents of the segregant layer and the excited volume. Segregation of antimony to boundary dislocations depends on dislocation character. Alloy composition (in atomic percent) was 68.1 Fe, 16.1 Cr, 14.2 Ni, 0.79 Si, 0.46 Sb, 0.20 Mn, and 0.12.

In this work two inconsistencies in the analyses for diffusive-plastic cavity growth are been pointed out. The plastic hole growth limit and the agreement with the Needleman and Rice analysis in the C and A and M and N models are due to inappropriate mechanical equilibrium conditions in the solution of the diffusive growth equations. Also, physically correct equations for the enhancement of diffusive growth rates by plastic flow have been derived.

A recently implemented fracture control plan for structural steel highway bridges makes use of a linear relation to describe the effect of strain rate on the ductile/brittle transition temperature as a function of yield strength. Literature data show that the predictions of the aforementioned relation are not general. An alternative analysis is offered along with a qualitative model for understanding the phenomenon. Results of an experimental program investigating microstructural effects on the ductile/brittle strain rate dependence are also presented. The results exhibit linear behavior of {Delta}/sub db/ versus {Delta}4v/{sigma} where {Delta}/sub db/ is the transition temperature shift, {sigma}is the yield stress, and {Delta}4v is the change in yield stress caused by strain rate. The magnitude of the temperature shift, however, is dependent upon the test specimen used. Factors discussed include microstructure, type of test specimen (Charpy V-notch, nil ductility temperature [NDT], modified NDT, or compact toughness), crack initiation versus crack propagation, and implications for regulatory bodies.

The influence of surface-applied Ca,Ce, Hf, La, Y, and Zr nitrate-converted oxides on the oxidation behavior of Co-15 weight percent (w/o) Cr, Co-25 w/o Cr, and Ni-25 w/o Cr alloys at 1000{sup 0} and 1100{sup 0}C in 1 atm O/sub 2/ was studied. The surface oxides were most beneficial on the established Cr/sub 2/O/sub 3/ forming alloy. Surface-applied CeO/sub 2/,Y/sub 2/O/sub 3/, and La/sub 2/O/sub 3/ were effective in reducing the growth rate of the Cr/sub 2/O/sub 3/ scale and improving the scale adhesion. The presence of these surface oxides also prevented base metal oxide formation and changed the growth direction of the scale. All of these observed effects were similar to those found when the reactive element oxides were present within the alloys. However, the presence of surface HfO/sub 2/ made the oxide scales nonadherent causing a breakaway behavior at the early stage of the oxidation process. None of the surface-applied oxides showed any effects on the non-Cr/sub 2/O/sub 3/ forming alloy, and they acted as a semibarrier on the borderline Cr/sub 2/O/sub 3/ former. Unlike the case of dispersoids present in the alloy, these surface-applied as a semibarrier on the borderline Cr/sub 2/O/sub 3/ layer at alloy Cr levels lower than those normally required to form the Cr/sub 2/O/sub 3/ scale.

In this paper a preliminary report is presented of the effects of gamma radiation on phenol antioxidant additives to PVC, polyethylene and polypropylene used for food packaging. Attention is drawn to the diminution of antioxidant levels after irradiation doses of 10kGy.

To investigate coastal changes, analysis of wave-induced sand movement (littoral drift) using two models and experiments with a wavemaking waterway with a length of 205 m, a width of 4 m, and a depth of 6 m were conducted to compare theoretical and actual values. The first model is a coast change model for long-term forecast. It was used (1) to investigate wave behavior, including refraction, diffraction, and breaking, around structures on cost, (2) to estimate the wave energy and littoral drift on coast and estimate the sand supply from rivers according to their flow and velocity, and (3) forecast coastal changes according to the coast line advance and retract calculated using

the sand conservation formula. The second model is a three-dimensional coastal change model for short-term forecast. It was used to calculate the distribution of waves and coastal streams, relate the intensity of local waves to the quantity of littoral drift, and forecast the coastal changes according to the sand conservation formula. The theoretical values obtained from the first model well agreed with actually measured values. (3 figs)

This is a comprehensive, independent handbook giving full information on the criteria for identifying products as non-polluting. Buying agents will in many cases not be in a position to establish the non-polluting quality of products for themselves or to choose among the many types the one product that is least likely to pollute the environment. The book brings light into this complexity and facilitates the choice of many products from the point of view of environmental protection. Furthermore any manufacturer of a product or system will be interested to learn about the demands public buyers will in future make on their products. The following groups of products are analyzed as to their non-polluting quality, and are described: products for use in offices, and general equipment - motor vehicles - building construction - underground working - energy management - water management - washing, dry-cleaning, and hygiene - horticulture and landscaping - problems of waste disposal. With 47 figs., 20 tabs.

The three contributions contained in the volume consider pollution a challenge to municipal policy. 'Municipal environmental policies in the late 19th century - an example of municipal waste removal' analyses the municipal administration of services, the municipal socialism trend, the influence of the government and the adaption of the municipal financial system to changed requirements and situations. The second paper 'politics - economic theory of public pollution abatement - scope and financing' basically reviews the theory of public goods. The third contribution focuses on a comparative evaluation of the financial behaviour of selected regional corporations in North-Rhine Westphalia during the period from 1975-1982. The analysis reveals considerable local and temporal differences in the financial policy of the relevant service administrations. (HSCH).

In order to cope with the variation of electric power load, a reseach and development on the system for storing electric power by advanced batteries has been carried out since 1980 as a 11 year project constituting a part of the Moonlight Project. This article is to introduce concretely the present state of the research and development. This system development comprises the development of large capacity and high performance secondary batteries themselves and the development of technology to interconnect the DC battery electric power storage system with the AC commercial power system, as well as the system technology thereof. There are such four kinds of the advanced batteries as sodium-sulfur battery, zinc-chlorine battery, zinc-bromine battery and redox flow type battery. In case of system technology development, a 1,000 KW class battery electric power storage system with a selfexcited inverter using modified lead storage batteries was constructed in Tatsumi Substation of Kansai Electric Power Co., Ltd. and a system test was started in October, 1986. Successively, it is planned to construct a 1,000 KW class pilot plant in 1988 onward. (13 figs, 2 tabs)

The report outlines the present status of radiation and imaging services in 13 African countries and formulates recommendations for the attention of Member States. All aspects of radiation and imaging services throughout the Region need considerable improvement. This will need careful planning to ensure the best use of available personnel and to avoid unnecessary expenditure. The current shortage of trained personnel can be met by improving existing programmes and initiating new ones within the Region; some degree of standardization would be advantageous. Cooperation throughout the Region, the enactment of radiation laws, and the help of the Regional Office for Africa and subregional offices could change the existing unsatisfactory status, which in some areas may even be

described as dangerous. In this way progress could be made towards health for all by the year 2000. Also available in French. 4 tabs.

Fluorine-doped tin dioxide layers were produced by spraying an organic tin solution onto a hot substrate. The substrates were common window glass, pyrex and black enamelled steel. Best results were obtained with black enamelled steel, in which case typical values of the spectral selective layers were: a solar absorptance of 0.92 and a thermal emittance of 0.15. Investigations of the optical and electrical properties show that optical behaviour in the 3-10 {mu}m region conforms well to the Drude theory. Ageing tests were carried out in air and in vacuum. In vacuum above about 250/sup 0/C ageing effects occur, which are related to a decrease of the SnO-fraction of the layer. The effect of sodium, which can diffuse from the glass substrate into this layer, was also investigated. Experiments show that only unrealistically high concentrations of sodium show significant changes in the properties of the layer.

Transparent conducting zinc oxide films have been prepared by reactive sputtering in an Ar/H/sub 2/ mixture. The optical and electrical properties of the films are presented and discussed. The effects of different post-deposition thermal treatments have been also investigated. ZnO/CdTe heterojunctions have been prepared by sputtering ZnO films on p-CdTe single crystals. The highest photovoltaic conversion efficiency of the solar cells obtained was 6.8%.

The influence of the deposition parameters on the electrical and optical properties of very thin silver films prepared by magnetron sputtering was studied. To evaluate the film properties a method was used, which is based on simple optical transmission measurements, and was proposed recently by one of the authors. The results show that the specific resistivity, the plasma energy and the optical resistivity of films below 30 nm thickness are very sensitive to such deposition parameters as cathode power density. It is concluded that the obtained variations in the optical and electrical properties are related to the density of the sputtered films.

Five different forms of spectrally selective black cobalt solar absorber surfaces have been prepared using techniques of electrodeposition, chemical conversion and thermal oxidation in air respectively. The dependence of surface optical properties on deposition process parameters has been investigated. Composition and microstructure have been examined using a range of surface analytical techniques. Surfaces have been exposed to elevated temperatures in air and optical properties have subsequently been remeasured. Two forms of black cobalt, a cobalt oxide hydroxide coating formed by chemical conversion and a cobalt oxide coating formed by thermal oxidation in air, are shown to exhibit favourable optical properties for long term use as selective solar absorbers.

The temperature stability of solar selective absorbing Cr-SiO cermets on Cu and Cr/Cu substrates was tested. The cermets were prepared by rf sputtering. Thermal annealing up to 900/sup 0/C was done in air, Ar and vacuum for periods up to 30 days. Some crystal growth and stable optical properties were observed.

The absorber-reflector tandem configuration is used for the realization of a selective absorbing surface for the photothermal conversion of solar energy. The infrared reflector consists of a stainless steel substrate, covered or not with a W or Mo thick film. The visible absorbing function is realized by a thin, low cost, Fe-Al/sub 2/O/sub 3/ cermet film. The cermet films are prepared by rf cosputtering onto a rotating stainless steel substrate. The target consists of a circular Al/sub 2/O/sub 3/ plate covered with small discs, the concentration varying with the Fe disc number. The optical properties of the thin Fe-Al/sub 2/O/sub 3/ films are studied as a function of the Fe volume fraction from 0.2 to 0.9. The dielectric function is calculated from the reflectivity and transmittivity measurements in the 300-50 000 nm spectral range. The films exhibiting the required selective properties (high absorptivity in the visible, high transparency in the infrared) are selected. A sandwich, composed of a thin Al/sub 2/O/sub 3/ antireflecting film, the cermet film (with adequate thickness and composition) and the reflecting substrate, exhibits a good selectivity for

the photothermal conversion at low and middle temperatures ({alpha}=0.95; {epsilon}300 K)=0.06; {epsilon}700 K)=0.14).

Good durability of solar absorber coatings is one of the most important preconditions for their application. Since the lifetime of an absorber should be at least ten years, a prediction of the ageing behaviour by accelerated ageing tests is very desirable. In general the ageing of the coatings due to temperature loads is caused by chemical or diffusion processes. The temperature dependence of the chemical reaction velocities as well as the diffusion constants is described by Arrhenius' law. Therefore an increase of the test temperature leads to an accelerated ageing. The temporal variation of the optical properties of the layer (e.g. solar absorptance and thermal emittance) at high temperatures can be transformed to lower temperatures using Arrhenius' law, if the degradation process does not change in the considered temperature range and the investigated time intervals. Then an estimation of the ageing behaviour and of the lifetime at operating temperature is possible. This method has been applied to copper-oxide coatings and to Ni-MgF/sub 2/ cermets. The specific ageing processes have been investigated by Auger electron spectroscopy combined with energy-dispersive X-ray analysis, which has shown, that the degradation of the copper-oxide layers is caused by chemical processes while the ageing processes in Ni-MgF/sub 2/ coatings are dominated by diffusion processes.

Selective optical properties can be achieved by a suitable surface roughness. Chracteristic parameters describing the roughness of the surface are the rms-roughness, the rms-slope, and the correlation length. Due to the dimensions of the investigated surface profiles the roughness measurements require scanning electron microscopy for surface imaging. For the statistical evaluation the image data are processed in a computer system, which performs the calculation of the autocorrelation function and the correlation length of the surface structure. Another approach uses a relation between the surface roughness parameters and the spectral reflectance, as given by a statistical scattering theory. The approximation of the measured spectral reflectance in the infrared range by this model as well as the SEM image analysis is used for characterizing the surface roughness of copper-oxide and chromium solar absorber coatings.

The density of states distributions near mid gap in a series of hydrogenated amorphous silicon films have been determined from space charge limited current measurements. The measurements were made on Au/a-Si:H Schottky diode structures prepared by reactive RF sputter deposition. Samples with hydrogen concentrations near 16% as determined from infrared absorption had densities of states of 3 x 10/sup 14/ states/cm/sup 3/ eV. The experimental results indicate that high quality a-Si:H films with low densities of states can be obtained under certain deposition conditions and that the density of states at mid gap is hydrogen concentration dependent with a minimum near 16%. For a given hydrogen concentration, films thicker than 2 {mu}m yielded the lowest density of states consistent with a model in which diffusion currents can be neglected and where surface and interface layers have a higher defect density than the bulk of the film.

We report for the first time the optical absorption and photovoltaic characteristics of thin films of Cu/sub 2/SnS/sub 3/. Films obtained by the direct evaporation of the synthesized compound were observed to be deficient in copper, while those grown in an atmosphere of copper vapour were observed to be more stoichiometric. Both sets of films are characterised by indirect and direct absorption edge properties. The indirect absorption edges are at 1.065 and 1.510 eV, while the direct band edges are at 1.658 and 1.770 eV for the copper deficient and stoichiometric films respectively. The stoichiometric film is characterised by p-type semiconducting properties while a Schottky type solar cell developed from it is observed to have potential photovoltaic characteristics.

It is shown that thick transmission phase holograms can either be chromatically selective or nonselective depending on the design of the geometrical conditions of recording and processing of the holograms. Curves calculated from theory show

that, by appropriate selection of recording parameters and geometry, holographic optics can be fabricated to use almost the entire useful spectrum of the sun with a reasonably good efficiency.

Energy transfer between fluorescent dye molecules and small silver particles can improve the fluorescence intensity for the dye, provided that the silver particles are of a suitable size and form to amplify the total absorption and fluorescence. This mechanism provides a possibility for extending the range of dyes which could be used in fluorescent collectors to longer wavelengths, by increasing the quantum yield and long-term stability of dyes absorbing in the NIR. Composite material models of the optical characteristics and measurements of the absorption, fluorescence and fluorescence lifetime are used to investigate this effect.

Two glass types for luminescent solar concentrators are presented: Type 1 is a silicate glass activated with Yb/sub 2/O/sub 3/, Nd/sub 2/O/sub 3/ and Cr/sub 2/O/sub 3/. This type shows luminescence in the region 970-1080 nm. It is possible to use it in combination with a silicon detector. The glass type 2 is a borosilicate glass activated with UO/sub 2/. Its wavelength region of luminescence is 510-560 nm. It can be used in combination with a CdS/Cu/sub 2/S or GaAs photodetector respectively.

We investigate the radiative heat transfer between blackbody-like surfaces confining an infrared-absorbing gas layer. Spectrophotometric measurements on selected gases lead us to optimized compositions with sulfur hexafluoride, propyne, and different freons. Theoretically, the gas is able to diminish the radiative heat flux across a 1 cm thick slab by a fator of {approx_equal}0.7 in comparison with the case of a nonabsorbing medium. Infrared-absorbing gases seem to offer interesting possibilities for improved transparent thermal insulation of windows.

Two theoretical minima of thermal conductivity are presented. Thermal conductivity clearly changes if different kinds of bulk materials are used, but this dependence is not the subject of the paper. Instead, it shall be shown how thermal conductivity can be minimized with one chosen kind of bulk material with a constant amount of bulk material per volume. (1) Different transparent insulation materials (TIMs) can be built of one certain kind of bulk material by selecting different structures, all of them having the same weight per volume. 5% bulk material and 95% air are typical values. It shall be shown that the minimum thermal conductivity is reached by a homogeneous distribution of the material. Silica aerogel has the minimum thermal conductivity which can be reached with silica because it is quasihomogeneous in relation to thermal radiation. (2) It is known that materials with a low thermal conductivity can be improved only by a small amount by a selective absorber touching the TIM. There has to be an air gap between the selective absorber and the transparent insulation. In this paper a method is proposed to calculate the dimensions of the gap for still air so that the conductive and the radiative thermal conductivity each have the minimum value.

At ambient temperatures, transparent silica aerogels as well as translucent granular fillings are excellent superinsulating spacers if evacuated. Thus their use in windows and covers for passive solar systems is extremely promising. Thermal loss coefficients under variation of radiative temperature, sample density, boundary emissivity and internal gas pressure are presented. Furthermore, the scaling of the solid conductivity with density is discussed.

Transparent insulation materials for solar energy applications are classified and described in this paper. An experimental setup with an integrating sphere for the whole global spectrum range having a large entrance port is capable of measuring angle-dependent directional-hemispherical transmittances for planar samples and nonplanar structures with acceptable accuracy up to proportional to 70/sup 0/. The theoretical description of such structures allows to calculate directional transmittances even for combinations of different kinds of layers,

for instance to determine seasonal variations of monthly-averaged transmittances for the whole cover system.

This paper summarizes the results of a program initiated at the Naval Research Laboratory to test conventional and state-of-the-art solar power space systems by flying them aboard satellites. The program (approximately nine years in duration) confirmed the practicality of improvements in advanced silicon solar cells such as textured surfaces, shallow junctions, back surface field and back surface reflector techniques, as well as novel methods of bonding coverslips to conventional cells. In addition, the performance of gallium aluminum arsenide solar cells was first tested in a space environment and demonstrated to be satisfactory. Finally, advanced silicon cells such as lithium-diffused and vertical junction cells, which were reported to be radiation resistant on the basis of measurements in the laboratory, were found unsuitable for extended space application.

The technique of replacing CdS by (CdZn)S for solar cells is well known. This replacement leads to a decrease in the junction lattice mismatch and in the difference of the electron affinities of the two materials (CdZn)S and Cu/sub 2/S. We present the results obtained on our fabricated backwall Cd/sub 1-y/Zn/sub y/S-Cu/sub 2/S solar cells (0 {le}y {le}0.15). The (CdZn)S layer is produced by a spray pyrolysis technique and the Cu/sub 2/S layer by a dry chemical process. The evolution and the improvement of the Cu/sub x/S stoichiometry with these fabrication parameters are presented. Also the photovoltaic characteristics of complete cells are studied under AM1 radiation. On 1 cm/sup 2/ area the best efficiency obtained is 4% for a zinc concentration of 5% (y = 0.05).

A mathematical model to simulate the heat transfer process of the directional solidification of silicon in a Bridgman-Stockbarger furnace was established. Finite element technique was employed to compute the temperature profile and the solid-liquid interface. The distributions of impurity concentrations were also predicted. Impurity with a small distribution coefficient showed a marked purification effect by this directional solidification process. Qualitative agreement between theoretical results and experimental measurements which used boron and aluminum as testing impurities was obtained.

Measurements are presented of the bidirectional spectral reflectance and directional-hemispherical spectral reflectance of Nextel-2010 black velvet, Solarcoat-50, Cusorb, Skysorb, Maxorb and Solarcoat-100 at wavelengths of 633 nm and 1152 nm. The data are consistent with surface form as revealed by scanning electron micrographs and surface roughness measurements.

The electrochromic properties of hydrated nickel oxide thin films electrochemically deposited by anodization onto doped tin-oxide-coated glass have been studied by transmittance measurements, cyclic voltammetry, Fourier-transform infrared spectroscopy, and ion-backscattering spectrometry. The spectral transmittance is reported for films switched in both the bleached and colored states. The photopic transmittance T/sub p/ can be switched from T/sub p/ (bleached) = 0.77 to T/sub p/ (colored) = 0.21, and the solar transmittance T/sub s/ can be switched from T/sub s/ (bleached) = 0.73 to T/sub s/ (colored) = 0.35. Also reported is the near-infrared transmittance T/sub NIR/, which found to switch from T/sub NIR/ (bleached) = 0.72 to T/sub NIR/ (colored) = 0.55 with a film thickness of 50 nm. The bleached condition is noted to have very low solar absorption in both the visible and solar regions. Ion-backscattering spectrometry was performed on the hydrated nickel oxide film, yielding a composition of NiO/sub 1.0/ (dehydrated). Cyclic voltammetry showed that, for films in the bleached or colored state, the reversible reaction is Ni(OH)/sub 2/ reversible NiOOH+H/sup +/e/sup -/. Voltammetry also showed that the switching of the film is controlled by the diffusion of protons, where OH/sup -/ plays a role in the reaction mechanism. Analysis of the hydrated nickel-oxide thin films by Fourier-transform infrared spectroscopy revealed that both the bleached and colored states contain lattice water and hydroxyl groups. The surface hydroxyl

groups play an important role in the coloration and bleaching of the anodically deposited nickel oxide thin films.

Electrochromic hydrated nickel oxide films were produced by reactive rf-magnetron sputtering followed by electrochemical treatment in KOH. Spectrophotometry was used to study the modulation of luminous and solar transmittance and to assess the durability. /sup 15/N nuclear reaction analysis indicated that coloration occurred upon hydrogen extraction. The investigated coatings appear to have very good properties for smart window applications.

Fundamental properties of a transmissive electrochromic device are described. The device consists of a semisolid electrolyte and a WO/sub 3/ film sandwiched by a pair of transparent conductive glass sheets. The transmittance of the device can be arbitrarily controlled within the range from 80% to 10%. The response time was found to be greatly dependent on the device size. The lifetime for repetitive operations is more than 10/sup 5/ cycles. Reasonably good durability has been determined. This device is capable of controlling the reflectance of a mirror, with the reflective layer coated on the either surface of the outer glass sheet. Details of this reflective device are also described. The reflectance of the mirror of the size of 25 cm x 6.5 cm can be changed from 72% to 20% within 4 s at 1.5 VDC. This device is suitable as an antidazzling mirror for motor cars.

The electrochromic response time and the chemical and electrochemical stability of amorphous tungsten oxide layers have been found to be adversely affected by the degree of porosity and hydration of the oxide layers, thus complicating the preparation of stable high speed electrochromic films. Based on our investigations of the microstructure of thermally evaporated tungsten oxide films we could overcome this problem by preparing high density (rho = 6.4 cm/sup -3/) tungsten oxide layers by flash evaporation or by reactive dc sputtering. In spite of the higher packing density (reduced free volume) which increases the electrochemical stability remarkably, the electrochromic response times of thin layers could be reduced to 50 ms, which is comparable to that of sputtered iridium oxide films. Even with 1.6 {mu}m thick dc sputtered tungsten oxide layers a response time of 400 ms for a contrast ratio of 1:2 and a response time of 5 s for a contrast ratio of 1:1000 could be achieved.

Electrochromic tungsten trioxide films have been prepared by direct current dc reactive sputtering of a metallic tungsten target in an Ar-O/sub 2/ mixture. Structural and optical properties of tungsten trioxide films have been investigated for different sputtering conditions. The operating electrochromic characteristics, current density and transmission, versus switching voltage have been presented. The dynamic properties of the system have been measured and calculated from a diffusion model. The diffusion coefficient of hydrogen in WO/sub 3/ was found to depend on sputtering conditions.

Polycrystalline WO/sub 3/ thin films were produced by CVD on fused quartz or SnO/sub 2/ coated pyrex substrates. The film structures were determined. The electrochromic phenomenon was observed in this kind of films in a two electrode electrochemical cell using protons as inserting ions. Electrochromic performances were investigated using a three electrode electrochemical cell in two different electrolytes.

Unstructured electrochromic mirrors with variable reflectance have been developed on the basis of hydrogen tungsten bronzes. The characteristic compounds of these devices are (1) solid ion-conducting layers (''electrolytes'') resulting in only a few micrometer thick all-solid-state systems, which can be enclosed between the substrate and a second glass plate and are thus protected from the environment, (2) integrated reflecting metal layers, and (3) hydrogen-storing electrochromic layers. Two basically different constructions are feasible. In ''diffusion-driven'' devices the bronze is formed (decomposed) by the chemical reaction (x/2)H/sub 2/ + WO/sub 3/ reversible H/sub x/WO/sub 3/; in ''field-driven'' systems an electrochemical bronze formation (decomposition), xH/sup +/ + WO/sub 3/ + xe/sup -/ reversible H/sub x/WO/sub 3/,

takes place. The modes of construction are presented and compared, the electrochemistry of the thin layer cells involved is discussed, the properties of devices according to the state of development are reported, and possible applications, e.g. as glare-free, inside and outside, automotive rear view mirrors with adjustable reflectance, are briefly described.

The aim of this work is to analyze the behaviour of a thin layer of semiconducting CdS on titanium, covered by a thin layer of a nonconducting polymer, and used as photosensitive anode in a photoelectrolytical cell. This anode structure should permit protection against photocorrosion effects, which are considerable for unprotected cadmium sulfide. It is also generally true for all the semiconductors with small band gaps. This coating will help to provide better long term stability of CdS electrodes. In this study the rate at which the photocurrent decreases in time as a function of the polymer thickness has been investigated. The choice of Formvar (a polyvinyl acetal resin in dioxane) as the polymer, was from our experience with this material in tunnel effect junction devices.

Polycrystalline TiO/sub 2/ film electrodes prepared by thermal oxidation were electrochemically reduced at cathodic potentials in acidic solutions. Changes in the spectral distribution of the quantum efficiency and the current-voltage characteristics at different stages of reduction were observed and related to ESCA (electron spectroscopy for chemical analysis) spectra of the surface and SIMS (secondary ion mass spectroscopy) depth profile analysis. Whereas a modest electrochemical reduction had a large effect on the anodic photoresponse in the short wavelengths range (250-330 nm) and almost none on the response at wavelengths close to the bandgap, more heavy reduction also affected the spectral response close to the bandgap and shifted the edge of the action spectrum towards shorter wavelengths. ESCA showed that the relative amount of hydrogen (present as hydroxy and/or oxyhydroxy groups) at the surface increased upon electrochemical reduction. SIMS profile measurements revealed that hydrogen was accumulated in a narrow (approximately 100-150 nm wide) zone just underneath the TiO/sub 2/-surface facing the electrolyte. The photoinduced cathodic currents that could be registered at the ''as prepared'' electrodes vanished upon electrochemical reduction. The observations were interpreted in terms of an increased dopant density due to implanted hydrogen in a low doped top layer (the recombination layer) formed during the preparation of the virgin electrodes. The observations are in qualitative agreement with the predictions that can be made from accepted theoretical expressions for a liquid junction as described by Popkirov and Schindler.

Spectrally selective (PbS)/sub 1-x/-(CdS)/sub x/ composite coatings have been developed using the solution growth technique. Optical, structural, composition and depth profile studies have been carried out. Composition and film thickness have been optimized to get solar absorptance ({alpha}/sub s/) and total emittance ({epsilon}sub 100/) values of 0.90 and 0.10, respectively.

We studied the behavior of two neopentylglycol (NPG)/pentaglycerine (PG) mixtures for thermal energy storage. The mixtures investigated had mass concentrations of 33% and 70% of PG. We maintained these mixtures at different temperatures over different periods of time. We observed an exponential time and temperature evolution of the degree of conversion of the exothermic process detected on heating from the holding temperature. We investigated the modification of the temperature on which this exothermic process occurs by submitting the mixtures to these thermal treatments. By doing so we show that these mixtures can be used for a wider range of energy storage applications.

The biotechnology industry is evolving rapidly. The authors project that U.S. biotechnology industry sales will move from about $400 million in 1987 to more than $25 billion by the year 2000. Over the past decade research has focused on three primary areas: pharmaceutical and health-care products, agricultural products, and chemicals. Numerous biotechnology-based products in each area have already been commercialized. This article reviews industry progress and key

technological challenges, profiles six leading biotechnology companies, and gives a prognosis of the industry's future prospects.

Qatar's demand for energy has increased tremendously during the last decade due to expanded economic activity since the early 1970's and subsequent diversification through development of downstream industries. Most of the energy requirement is met by natural gas. The purpose of this paper is to describe the development of a gas-oriented producing country and the operating philosophy for maintaining maximum efficiency and preserving the nation's natural resources.

Recently, the power-management section at Eastern Utilities Associates (EUA) has begun using a cost criterion to determine the optimal time slots for scheduling outages of generating units. This paper describes the outage-cost criterion, outlines the coordination procedure, and presents two actual case studies to illustrate practical applications for the EUA system.

This book presents papers on renewable energy sources. Topics considered include the UN response to the challenge of the energy transition, technology transfer, national activities and trends, the Nairobi program of action, the United Nations conference on New and Renewable Sources of Energy, and future prospects.

In this work, the author, a former Deputy-Secretary-General of the United Nations Conference on new and Renewable Sources of Energy highlights the origin, rationale and structure of the conference.

This work presents an overview of present and future technologies for the harnessing of new and renewable sources of energy based on technical papers presented at the Conference on New and Renewable Sources of Energy.

This Chapter summarizes the national activities and trends for the exploitation of resources, as reflected in national reports distributed at the United Nations Conference on New and Renewable Sources of Energy (August 1981) and updated from additional sources.

In this work the author presents a detailed analysis of the UN Conference on New and Renewable Sources of Energy.

The work reviews the Programme of Action adopted by the Conference (the Nairobi Programme of Action).

In this work the author presents a discussion of future prospects for the harnessing of various sources of energy.

The acidity of rain is essentially attributed to carbonic acid that results from the dissolution of CO{sub 2} existing in the atmosphere, and pH 5.6 is calculated from an equilibrium theory. However, actual rain has a higher acidity in most cases and the causative substances are almost exclusively SO{sub 2} and NOx. The pH averaged over 100 points across Japan is 4.5, and it is also between 4 and 5 in Tokyo. In some urban areas, there are sources of alkaline substances that serve for neutralization. The value of PH was in the range from 4.0 to 5.0 in Europe from 1978 to 1982, while the yearly average of PH is 4.2 - 5.0 in areas ranging from the south side of the U.S's Great Lakes to southeastern Canada. A wide variety of factors including substances of natural origins should be taken into account in investigating the acidification of rain. (24 refs, 8 figs, 2 photos)

The /sup 238/U, /sup 234/U and /sup 226/Ra in the river-bed soil were investigated on those adsorption and contents. The soil samples were taken from the upstream area of Yoshii-River in Okayama Prefecture. In this area, uranium mine has been developed and nuclear fuel plants have been operated for producing uranium enriched by centrifugation of UF/sub 6/. The radioactive waste effluent has been released into the river. Six soil samples were sieved into six fractions according to particle-size, respectively. The preliminary experiment concluded that the concentrations of the three nuclides increased with decrease in particle-size of soil on all samples, though the particle-size distributions varied with both sampling location and date. Thus the concentration of each

nuclide in a fine river-bed soil was found to show effectively the latest level of pollution in the river water. The concentrations of /sup 238/U in each fraction of the two samples were measured by {gamma}-ray spectrometer with intrinsic Ge-detector and /sup 226/Ra also with Ge(Li)-detector. The soil surface-area of each fraction was measured by B.E.T. method. The concentrations of each nuclide in the soil were directly proportional to the specific surface-area. The concentrations of both nuclides adsorbed on the soil and the /sup 226/Ra//sup 238/U ratio were estimated with respect to the specific surface-area in each fraction. It was found to be useful for monitoring of nuclear fuel plants to pay attention to the /sup 226/Ra//sup 238/U ratio as well as the /sup 234(235)/U//sup 238/U ratio.

The influence of acid snow to the environment was studied in Hokkaido, Japan. To clarify this point, pH, electro-conductivity, SO{sub 4}{sup 2}-, NO{sub 3}-, Cl- as major anions, NH{sub 4}+, Na+, Ca{sup 2}+, and Mg{sup 2}+ as cations were measured in core samples of fallen snow collected in 11 regions of Hokkaido in 1986. The results were summarized as follows: (1) The average pH values ranged from 4.6 to 6.5. (2) The concentration of Cl- ranged from 0.85 to 12 mg/l, and this matrix originated mostly from chloride compounds in sea salts. (3) The concentration of Na+ ranged from 0.37 to 7.7 mg/l, and the matrix also originated from sodium compounds in sea salts. In contrast, Ca{sup 2}+ originated mostly from calcium compounds in asphalt dust, and the concentration ranged from 0.22 to 9.2 mg/l. (4) The concentration of hydrogen ion (as a pH value) was predictable using the differences between the concentrations of Ca{sup 2}+ and excess SO{sub 4}{sup 2}- plus NO{sub 3}- in equivalent weight. (8 figs, 2 tabs)

Selenium is believed to be an essential tracer element in low amounts but toxic at high concentrations (Underwood, 1971). Because of the potential toxicity of selenium, the mobility and movement of selenium in soil, aquifer and river water systems are of concern (NAS, 1976). The retention of selenium by solid phases is dependent upon the oxidation state of selenium, the minerals and mineral coatings present and chemical composition (pH, ionic strength and chemical constituents) of the water (Geering et al., 1968). Selenite forms strong coordination type bonds, while selenate forms weaker ion-pair type bonds. The relative intensity of binding of selenite and selenate is also affected by the solid on which binding occurs. For example iron oxides bind selenium more strongly than silicon oxides or silicates. Experimental and modeling results of the interaction between redox potential, dissolved constituents and retention or release of selenium are discussed here. First, selenium behavior under redox conditions are discussed, then the affect of changing redox conditions from reducing to oxidizing and from oxidizing to reducing are explored.

An apparatus is described for determining the shear velocity of a formation traversed by a fluid-filled borehole, comprising: means for obtaining waveforms from a dipole acoustic investigation of the formation relative to a common location in the borehole; means for determining from the waveforms a flexural mode phase velocity as a function of frequency; means for selecting an estimated shear velocity; means for theoretically determining a flexural mode phase velocity as a function of frequency, from the estimated shear velocity; means for fitting the theoretically determined flexural mode phase velocity to the waveform-determined flexural mode phase velocity; means for iteratively actuating the selecting means, theoretically determining means, and fitting means for additional estimated shear velocities until a least error fit is identified; and means for reporting the last-estimated shear velocity as the shear velocity of the formation.

It is shown that the requirement of fission suppression cannot be effectively fulfilled in soft spectrum systems. The attenuated neutron capturing power of fertile media, due to the resonance self-shielding, cannot prevent neutrons from being thermalized and causing fissions in these conditions. The presence of slowing-down media in the system proves incompatible with high breeding efficiency. Consequently, the necessity of consideration of the resonance self-

shielding and the resignation of moderators in fissile breeding systems has been postulated.

In the frame of the HTMR (Hybrid Toroidal Magnet Tokamak Reactor) conceptual study, a particular effort has been devoted to the preliminary design of a Li{sub 2}O breeding blanket. The attention paid to the analyses of the blanket materials from the point of view of their nuclear properties allowed the conception of a blanket configuration which offers a high breeding ratio and shielding effectiveness in spite of a rather reduced thickness. The high efficiency features of this blanket allow its application also to other next generation tokamak reactors.

A liquid lithium tubolar breeding blanket concept has been studied which could be applied to NET/INTOR or other next generation Tokamak reactors. A high breeding ratio can be achieved using a moderator medium, without enriching lithium in the Li6 percentage. Preliminary neutron and gamma flux and thermohydraulics calculations have shown the feasibility and efficiency of our concept.

The Lithium Blanket Module (LBM) is an approximately cubic blanket module that will be installed on the Tokamak Fusion Test Reactor (TFTR) in late 1986. Measurements of neutron transport and tritium breeding will be made with the TFTR D-D and D-T fusion neutron source. The final design and fabrication of the LBM, and the status of preparation for the experimental program is reported.

The arrangement of a solid blanket with the radial canister concept appears to be very attractive. For an experimental device such as NET where the space available for the blanket is fairly small, the useful thickness of the breeder appears questionable. Some sketches and rough thermo-mechanical calculations confirm this critical issue and emphasize problems associated with the complexity of the helium circuit manifoldings and the difficulty of the segments withdrawal.

The commercial use of the D-T fusion will not be possible unless the necessary tritium can be produced. The number of produced tritium nuclei has to be higher than the number of fusions. For that, we surround the plasma with a lithium-containing blanket. The fusion neutrons which are injected into this blanket are captured after slowing down by the {sup 6}Li and then produce tritium. A detailed study of the neutronic properties and of the calculation process results in the conclusion that the tritium production will be difficult but possible in a commercial D-T fusion reactor.

A transient tritium hold-up and permeation model is developed and applied to a simplified conceptual design of a water cooled Li{sub 17}Pb{sub 83} blanket. Tritium inventories in the blanket associated with diffusivity, solubility and trapping effects are estimated. The model is applied to the INTOR/NET LiPb blanket design. Assuming a daily LiPb reprocessing frequency a tritium production rate of 64 grams per day yields a total tritium inventory in the blanket comparable to that of the tritium system or trapped in the first wall. The diffusion-limited permeation rate (neglecting oxide layers effects) reaches 4.2 g/day. The extrapolation of these results to reactor relevant conditions aggravates the permeation and the associated problems.

The solubility of hydrogen in the liquid 17Li83pb alloy has been evaluated in the 400-500{sup 0}C temperature range for low (approx. 1 mbar) and high (approx. 1000 mbar) hydrogen partial pressures. No noticeable difference in the order of magnitude of the Sieverts' ratio has been observed between both ranges of pressure. Moreover, for high partial pressures, the Sieverts' ratio does not appear to be modified by the presence of lithium oxide in contact with the alloy.

This is a continuation of ''IL MANTELLO'' study that is being performed at the Frascati ENEA center. The goal of the study is to perform a preconceptual design for a gas cooled solid breeder blanket that fits into the NET device and can be

extrapolated to a full size power producing Tokamak reactor. The ''IL MANTELLO'' concept together with the main design progress and improvements are shown.

A study of the neutronic effects of several first wall materials for a hybrid blanket is performed. The ANISN transport code has been used in the analysis. Results show a better nuclear performance of graphite when compared to other typical materials as SS-316 and niobium. Spectral effects of the materials are discussed, and some structural considerations of the graphite design are resumed.

Time dependent neutronic evolution is analysed for a hybrid blanket with a pulsed external neutron source. The analyses have been made with TIMEX transport code. Delayed fission neutrons and source time of flight effects have been evaluated. The influence of these effects on the expected energy deposition and cumulative neutronic damage are also summarized.

The variation of the basic design parameters in two different cavity designs for ICF systems is shown as a function of differently moderated spectra for the neutrons and gamma particles leaked from the target. The results show the different behaviour of the two cavities for the same type of source and the necessity of considering all the effects simultaneously, the analysis of one isolated effect not being enough to obtain the critical design function.

The purpose of the work described is to develop a technique for obtaining applicability of an in situ welded joint to a split centre solenoid in a tokamak system. Solution to an example problem is also presented for illustrative purpose.

A model pulsed coil (RPC-II) with an average ramp rate of 200 T/s has been built and tested in order to meet the requirements of superconducting poloidal coils for a medium size Tokamak. The average and maximum pulsing rates in charge-up period were 200 T/s and 314 T/s, respectively. The associated a.c. loss per pulse was 0.4 kJ which was only 0.3% of the energy stored in the coil. After twelve pulses with a repetition period of 15 min., no change in the pulsing characteristics of the coil has been observed. These results showed the scientific feasibility of superconducting poloidal coils to be used in long-pulse medium size tokamaks.

A symmetric 3-coil arrangement of the TESPE superconducting 6-coil torus was successfully operated. The bath-cooled coils reached their design current in the first run. Investigations were performed on cooling, strain effects, safety discharges and conductor stability. Cooldown until stable operation could be achieved within 100 hours. The measured strains partially agree well with calculated data. Fast energy removal had an efficiency of about 90%. The stability behaviour varied strongly with the operating current. In these first runs the system showed also its suitability for magnet safety investigations.

Design guide lines for the superconducting PF coil development at KfK are outlined. The status of the conductor development including low loss superconducting wire fabrication and transient heat transfer measurements is reported.

Manufacture of the toroidal field (TF) magnet of ASDEX Upgrade (AU) was started in January 1984. The manufacturing method differs essentially from that applied for other comparable D-shaped coils, and is discussed on the basis of tests conducted with a coil model. Numerous tests are needed to develop an insulation system of high mechanical strength. The test results available are summarized. Finally, some manufacturing aspects of the large cross-section copper conductors are described.

The EURATOM-LCT coil was tested as a single coil in TOSKA. Load cells were mounted in the support structure to monitor forces between coil and vacuum vessel during cooldown and coil charging. Disturbances of components by magnetic fringing fields were carefully considered. To investigate the mechanical behaviour and compare it with FEM-calculations the coil was equipped with strain

gauge rosettes and displacement transducers. Van Mises stresses in the coil case are in agreement with calculations. As known from special investigations during coil manufacturing the average radial Young modulus varies along the periphery caused by the different curvatures. This leads to differences with FEM-calculation (larger gaps between winding and coil case) assuming a larger constant Young modulus performed at the beginning of the project.

The FTU tokamak, to produce the required performance, will be operated at very high levels of poloidal magnetic field for a large number of shots (> 10{sup 4}). To assess the feasibility of the poloidal windings and of the mechanical support structure, numerical methods to compute the electromagnetic loads under normal and fault conditions have been developed and a 3-D finite element stress analysis code has been used. Some typical results obtained are illustrated.

The conceptual design of a poloidal coil system with resistive radiation-hardened coils located near the plasma surface is described. For the proposed TFCX tokamak, resistive coils offer several attractive features, including sufficient inductive current drive to accomplish the mission without rf current drive, plasma configurations with MHD beta limits in excess of 10%, and flexibility for future accommodation of optimized plasma shapes and/or divertor geometries. The resistive and inductive powers required are minimized by implementing both ohmic heating/current drive and plasma equilibrium functions with a single system of parallel-connected coils, and by locating these coils within the toroidal coil bore.

The Large Coil Test Facility (LCTF) is being used to test superconducting toroidal field coils about one-third the size of those for INTOR. Data were obtained on performance of refrigerator, helium distribution, power supplies, controls, and data acquisition systems and on the acoustic emission, voltages, currents, and mechanical strains during charging and discharging the coils.

Hoop stresses, up to 100 MPa, in the poloidal field coils of TORE SUPRA have to be reacted back to the main body of the coil where a conductor ends or is twisted for an interturn or an interlayer transition. The load is taken by shear stress through the insulation. Carefully designed configurations, based on 1D, 2D and 3D analysis results, limit the shear stress levels to 15 MPa. A fatigue test of a conductor termination has shown that the experimental results are in good agreement with the calculated stresses.

After a short summary of the main features of the TORE SUPRA long pulse Tokamak poloidal field system, the manufacture process of the six larger coils is described. The hollow conductor copper cross section is almost equal to the water channel one so that the coils can withstand more than 30 s pulses at full power. The main difficulties arise from the exceptional size of these one piece coils which are up to 9 meters in diameter.

The Tokamak Fusion Core Experiment (TFCX) mission is to achieve ignition and long-pulse equilibrium burn; to the extent resources permit, TFCX should also serve as a focus for the development of future fusion technologies. Four options are examined for TFCX, with the most significant difference being in the choice of toroidal field (TF) coils -- either superconducting or copper. These preconceptual studies provide a comparative basis for narrowing the options prior to conceptual design. The options described here use superconducting TF coils. The designs are all on the same physics basis, satisfy common design specifications, and are costed using a common costing data base.

The study of residual stresses and strains in composite superconductor cables and winding packs is of great interest to designers of large coils because - the present state-of-the-art in structurals analysis and hardware fabrication does not give enough information on the self-equilibrating stresses within the coil immediately after completion of the manufacture, - the bending of future harder superconductors like Nb3Sn must observe narrower design limits imposed by manufacturing conditions as well as by allowable prestress levels derived from the ''superposition'' of various cycling elastoplastic stresses. Stresses and

strains in a circular bend during plastic forming and subsequent unloading are investigated.

The Mirror Advanced Reactor Study (MARS) was recently completed. This futuristic commercial fusion powerplant design study incorporates a magnet set that would advance the state of the art but is independent of the need for unknown development. The MARS magnet set consists of 60 magnets, including solenoids (superconducting and normal), C-shaped, and yin-yang pairs. The magnet set mass, coil, and case, exclusive of external supports, is more than 15 million kilograms. The system uses all presently available superconductors: NbTi, Nb{sub 3}Sn, and Nb{sub 3}Sn:Ti. Both normal liquid helium I and superfluid helium II are used for cooling. Energy stored in the system magnetic field is 5.5x10{sup 10} joules. In terms of stored energy per unit mass, MARS magnets are comparable to those magnets now under construction for the MFTF-B program at Lawrence Livermore National Laboratory.

Consideration is given to central support concepts for TF-coils. Three models using 2-D finite elements are applied to investigate the stress distribution in a vault. Some approximate formulas which describe the torque load of the central support are presented.

Some aspects for optimizing of the central ohmic heating coil of the ASDEX Upgrade tokamak experiment are given. The final OH system is described.

A general purpose CAD package is applied to the solution of problems related to fusion technology. The problems solved are the interacting electromagnetic and thermal fields in a resistive toroidal coil and the design of the poloidal field coils in Tokamak machines. In both cases, the procedure used is reported and the results obtained are displayed and discussed.

The JT-60 magnetic limiter coils (M coils) produce a separatrix magnetic surface in the divertor operation of JT-60. The M coils have to meet various design requirements from mechanical, electrical, thermal and vacuum engineering points of view, as well as problems related to plasma. The fabrication and assembling of the M coils have been performed successfully under careful quality control including mechanical, electrical and vacuum tests. The installation of the M coils on site has already been completed, and at present the bakeout test of the vacuum vessel is under way.

The design of the superconducting tokamak TORE SUPRA, undertaken by the EURATOM-CEA Association has been described. Fabrication details of the superconducting magnet, are given. The magnet is composed of 18 coils. Each coil is made of a NbTi superconducting winding, enclosed in a leak proof casing filled with superfluid helium, thermally insulated from a thick stainless steel casing which withstands the electromagnetic forces. The thick casing is made of two flanges and two rings hooped on the winding and assembled by automatic welding while axial pressure is applied on the flanges in order to provide a precompression of the winding.

A description is given of the poloidal field coil design system used for NET. This system is used to carry out sensitivity studies of the overall poloidal field coil currents to the plasma parameters (elongation, triangularity) and to the relative flux contributions from ohmic heating and equilibrium coils. The results from these are used to produce various poloidal field coil configurations for NET, and to examine the effects of machine size and maintenance access requirements on these configurations.

The NET system integration procedure is the process by which the requirements of the various Tokamak machine design areas are brought together to form a compatible machine layout. This is carried out in NET by allowing flexibility in the maintenance and access methods to the machine internal components which must be regularly replaced by remote handling, in segmentation of these internal components and in the number of toroidal field coils.

Modular Stellarator coil systems of the W VII-AS type with reactor dimensions are investigated. The total stored magnetic energy of the coil systems and the maximum magnetic flux density at the coils are calculated. Furthermore, the magnetic forces and mechanical stresses are evaluated, and two different support concepts for the coils are investigated: A single coil support scheme (outer and lateral support elements plus elastic padding), as well as a novel scheme of mutual coil support.

The HTMR (Hybrid Toroidal Magnet Tokamak Reactor) conceptual design is aimed to demonstrate the feasibility of a Tokamak reactor which could fulfil the scientific and technological objectives expected from next generation devices with size and costs as small as possible. A hybrid toroidal field magnet, made up by copper and superconducting coils, seems to be a promising solution, allowing a considerable flexibility in machine performances, so as to gain useful margins in front of the uncertainties in confinement time scaling laws and beta and plasma density limits. The optimization procedure for the hybrid magnet, configuration, the main design features of HTMR and the preliminary mechanical calculations of the superconducting toroidal coils are described.

Details are given of a conceptual LIB fusion device. (U.K.).

Three concepts for inertial confinement fusion (ICF) reactors are described and compared with each other, and with magnetic fusion and fission reactors on the basis of environmental impact, safety and efficiency. The critical technical developments of each concept are described. The three concepts represent alternative development paths for inertial fusion.

A 4.5-m-radius rotating fusion reactor made of silicon carbide and containing a moving 1-m-thick lithium-ceramic granular blanket can produce 3000 MWsub(t). The blanket operates at high temperature (>1200 K) leading to gross plant efficiencies of up to 60% using a combined helium-gas turbine (Brayton cycle) with a vapor bottoming cycle.

Recently, a small D-T fueled fusion reactor design based upon the Reversed Field Pinch (RFP) concept has been presented that predicts cost of electricity (COE) comparable to a light water fission reactor (LWR). A conceptual design, based upon a small, high-beta, low q, steady-state, high-current tokamak concept (MINIMAK) that utilizes a 50/50 mixture of D-T fuel, is examined. A mass-produced MINIMAKS is costed, and the resulting COE is around 56 milles/Kwh for a 12-unit power plant. Ways to reduce the COE will be discussed.

The dose distribution and the spectrum variation of neutrons due to the skyshine effect have been measured in the environment surrounding an intense 14 MeV neutron source facility. The source neutrons produced by D-T reaction penetrate 20-cm-thick concrete ceiling and upper part of side wall, and leak into atmosphere. The dose distribution and the energy spectra of neutrons around the facility to be a skyshine source have also been measured to enable the absolute evaluation of the skyshine effect. The skyshine effect was analyzed by two multigroup Monte Carlo codes, by discrete ordinates Sn code, and by the shield structure design code for skyshine. The calculated results show good agreement with the measured results in absolute values. These results must be useful as a kind of benchmark experiment on the skyshine phenomenon, as well as for shielding design of fusion facilities.

A detailed global dispersion compartment model for tritium in the chemical form HTO has been developed. Contributions from the 404 atmospheric nuclear detonations since 1945 have been evaluated in order to calculate the current inventory of tritium in the different reservoirs of the earth. A function describing the natural production of tritium from cosmic rays is developed. Consequences attributed to the release of tritium from a simulated fusion power plant as HTO was estimated. Only results from the accidental conditions are represented. The purpose is to determine on a global scale, as realistically as possible, the effect on the dispersion, inventory and exposition to man from tritium release from future fusion power plants.

Recent fusion reactor designs specify liquid Li{sub 17}Pb{sub 83} as breeder material candidate with water as coolant. From the safety stand point of view a break of the pressurized water tubes in the hot liquid blanket cannot be excluded. The interaction of the alloy with water under operation conditions (temperature and pressure) could therefore be a safety concern for the integrity of the blanket housing, since typical water inlet and outlet temperatures are of 280{sup 0}C and 320/350{sup 0}C with water pressure of approximately 15.0 MPa. Tests performed in a closed shock tube with small melt quantities show that one has to distinguish between short and long term interaction effects. Emphasis is given to the interpretation of the short term interaction effects which have a significant influence on the long term effects.

A Plasma Fault Protection System (PFPS) has been installed on JET and is able to terminate a discharge if dangerous plasma conditions develop, or if the discharge is otherwise unsatisfactory. A number of plasma signals are considered in real time by a microprocessor and when a particular plasma fault is recognised an appropriate response is issued to the plant.

For three different geometries of a water-cooled liquid Li{sub 17}Pb{sub 83} filled breeder blanket module the dynamic reponse of the structure has been calculated to study the potential of these modules in case of a coolant tube rupture. Numerical calculations with the code PISCES have been carried out taking into account the fluid-structure interaction and the elastoplastic behaviour of the structural material.

For any of the growing number of laboratories or small scale fusion facilities using or planning to use tritium, an Emergency Air Detritiation System (EADS) will be required to ensure minimal environmental tritium releases following an accidental release of tritium into the building atmosphere. All existing systems use a catalytic recombiner to oxidize the tritium with oxygen in the air to form tritiated water, followed by adsorption of this water with moisture from the air on drier beds. Several options are reviewed with particular emphasis on small fusion devices with low tritium inventories.

An overview is given of five separate studies all of which were performed in support of INTOR Critical Issue D: Tritium Containment and Personnel Access vs Remote Maintenance. The common thread running through these studies is the radiological safety element in the design and operation of the INTOR facility. The intent is to help establish a firm basis for comparisons between a reactor cell maintenance option which requires personnel access, and one which involves completely remote maintenance.

A loss of coolant accident in a blanket design proposed for NET is investigated. After the structural analysis of the damaged blanket module and the evaluation of the radioactive sources involved, an assessment is made of the containment barriers and associated protection systems.

The books (2 volumes) on ''Life assessment of dynamically loaded materials and structure'', are the proceedings of the 5th European Conference on fracture, held in Portugal 1984. The conference concerned the current status of methods and theories dealing with the subject. The papers presented included the topics: crack initiation, welds and welded joints, fracture toughness and fatigue, manufacturing processes, stress intensity factors, elastoplastic fracture mechanics, and metallurgical aspects, applications, non-metallic and pm materials, creep, and testing techniques. Three papers were selected and indexed separately. (U.K.).

A new test device was constructed to measure dynamic fracture, toughness under stress wave loading. Using the test device, temperature dependence of the dynamic fracture toughness of two structural steels, ASTM A533B steel and JIS SK4 steel, under K of about 1x10{sup 6}MPa{radical}m /s was investigated in the range of 20 to -100 C. The temperature dependence for the two steels was much moderate in comparison with that of the quasi-static fracture toughness. This is interpreted by no change of the microscopic fracture mechanism. Measured

stretched zone width also corresponds to the temperature dependence of the dynamic fracture toughness for the two steels.

The long term integrity of the pressure welds in the gas ducts of Magnox nuclear reactors is assessed based on the results of recent, extensive, ultrasonic examinations and arguments based on the fact that all welds survived pre-service, proof pressure tests. Probability density functions are derived to describe the defect populations in the inspected welds and used in a generalised probabilistic fracture mechanics assessment. These calculations show the risk of failure to be remote under normal operating and postulated fault conditions.

This paper presents the procedure in French PWE plants to check the validity of the design analysis hypothesis (particularly the fatigue loadings) after startup operation. The procedure is described which allows monitoring and bookkeeping of the actual loading cycles. Results may be used to validate design demonstration or to work out more realistic analysis. Improvements are proposed to monitor more preciesely the real fatigue damage.

The book comprises papers presented at the second European Community Conference on Radioactive Waste Management and Disposal, Luxembourg 1985. The conference is divided into a number of sessions headed by the following subject titles: treatment and conditioning processes, characterization of waste forms, multi-barrier systems, disposal in salt and clay formations, disposal in granite and into the seabed, and modelling and performance analysis. (U.K.).

The long life and high radiotoxicity of the alpha-emitting transuranics in radioactive waste provide an incentive for the constant improvement of existing processes and waste forms or the development of new alternatives, to isolate then safely from the biosphere. Five processes at differing stages of development are outlined, the products ranging between cement, glass and ceramics.

The paper reports on a panel session at the European Community conference on radioactive waste management and disposal, Luxembourg 1985. The session was devoted to the EEC programme on treatment and conditioning options for low and intermediate level waste. (U.K.).

Investigations into the radiation, thermal and mechanical effects in high level radioactive waste (HLW) glass, carried out by various research laboratories in the European Community, are reviewed. The radiation effects in HLW glass refer to i) Pu-238 doped samples which are examined with respect to leach rates and densities, and ii) ion bombarded samples which are studied for point defects, etching rates and microstructural changes. The work on thermal effects in vitrified waste concerns crystallization behaviour, and that on mechanical effects includes stress and crack studies. (U.K.).

In the paper, the costs of geological disposal of radioactive waste are initially evaluated for a certain number of representative cases of present tendencies in the European Community. These expenses comprise research, development and site validation costs, transport and interim storage costs and finally expenditure relating to various investment and exploitation phases of the disposal site as well as its closure. The possible ways of financing are subsequently reviewed and the financial charges which resulted are calculated for each considered scenario.

The paper is a report of a panel session at the European Community conference on radioactive waste management and disposal, Luxembourg 1985, concerning the safe and long-term disposal of high-activity and long-lived waste. The subjects discussed include: geological barriers including deep sea-bed sediments, engineered barriers, technological problems (repository construction, waste emplacement, backfilling and sealing), safety analysis, performance assessment of disposal system components, and finally institutional, legal and financial aspects of geological disposal. (U.K.).

The paper reports the concluding panel session at the European Community Conference on radioactive waste management and disposal, Luxembourg 1985. The panel considered the conclusions of two preceeding technical panels on high level waste (HLW) disposal and waste treatment processes. Geological disposal of HLW, waste management, safety assessment of waste disposal, public opinion, public acceptance of the manageability of radioactive wastes, international cooperation, and waste management in the United States, are all discussed. (U.K.).

Purified PE was doped with naphthalene, anthracene, and phenanthrene from its vapours. The amount of ion radicals of added molecules and the shape of the RTL curve as a function of dose and concentration of doped molecules were examined. At low temperature (77K), radiolysis, anion radicals (AR) of added molecules were formed. Movement of the AR and the subsequent recombination with cations results in the maximum RTL integral which is proportional to the concentration of AR. The dose dependencies of concentration of AR and integral of RTL reaches their maxima which is at a bigger dose in the former case than in the latter. This is connected with the quenching of RTL PE by radicals of radiation origin.

Oil saturated sandstone and limestone targets have been irradiated with 14 MeV neutrons. Gamma-ray spectra were accumulated and the {gamma}-ray intensities arising from inelastic neutron scattering reactions upon carbon and oxygen measured. The results are compared with the predictions of a simple model. They enable some features of the response of (n,{gamma}) tools used in oil well logging to be established and current uncertainties in understanding to be highlighted.

The paper describes the experiences in selecting, installing and commissioning an integrated Computer Aided Design (CAD) system into Rolls-Royce and Associates. The primary business of the Company is the design, development and procurement of nuclear and steam raising plant for submarines and the CAD system is employed in all three areas.

Doxylamine succinate, N,N-dimethyl-2-[1-phenyl-1-(2-pyridinyl)-ethoxy]ethanamine succinate is an antihistamine used primarily as a sedative. Carbon-14 labeled doxylamine succinate, required for toxicological studies, was synthesized in two steps starting from 2-benzoyl pyridine.

Solid solutions of hydrogen or deuterium in lutetium exhibit, when quenched across the well-known 170 K anomaly and/or irradiated with electrons at low temperatures, a residual-resistivity increase, {Delta}hosub(q) and {Delta}ho sub(irr). The energy dependence of {Delta}hosub(irr) has been fitted with electron-hydrogen displacement cross-sections, taking into account the secondary electrons produced by the primaries in the samples. Upon annealing, the introduced {Delta}hosub(q) and {Delta}hosub(irr) recover in the anomaly region; a kinetic analysis of the annealing stage gave activation energies for H-'defect' migration of Esub(m) (H, D) approx. 0.25 eV after both quench or irradiation, with a reaction order {gamma} approx. = 1. The defect creation after quench and irradiation is interpreted in the framework of the quasi-linear H-H pair structure parallel to the c-axis prevailing below the anomaly temperature as determined recently by neutron scattering.

Some of the questions posed were: 1) Can target cell populations be defined in the tissue for specific types of injury 2) Are there qualitative differences in the target-cell populations for different cytotoxic agents, e.g. resistant subpopulations of cells 3) What is the cellular basis to the volume effect (i.e. greater injury per unit volume with increasing volume of tissue treated) 4) What is the contribution of intracellular repair of potentially-lethal damage to the sparing of injury in late-responding tissues 5) What are the contributions of repopulation by colony-forming cells and cells with very limited division potential to the sparing of injury in the late-responding tissues 6) How well is functional (effector) cell number correlated with overall capacity for function 7) What is the contribution of stromal (including vascular) injury in the response of the parenchyma. A total of 90 contributions considered these

questions and others, in the following sections: the alimentary canal, skin, germinal tissue, vascular tissue, neuromuscular and glandular tissues, kidneys, bladder and liver, and lungs, models and strategy.

The present note is an appendix to the review of Potter et al (1983) and concentrates on studies of damage to the oesophagus and stomach, using heavily thorax-irradiated mice. The stomach and duodenum as sites of abscopal effects of partial-body irradiation, the influence of LET, and ileal malabsorption as a radiotherapy side effect are discussed. Substantial bibliography.

The murine data presented illustrate the influence of food consumption on the proliferative rate of the oesophageal epithelium during recovery from radiation damage. Refeeding at a time before the initiation of the normal hyperplastic response results in a decreased time interval between treatment and increased rates of cell proliferation, while reduced food consumption during the normal period of hyperproliferation results in reduced proliferative activity. The finding that recovery kinetics may be altered by changing food consumption patterns should be an important consideration in the analysis of antineoplastic agent-induced proliferative perturbations, as many treatments themselves produce reduced levels of food consumption.

In this report dose response data for gustatory tissue damage in patients given total radiation doses ranging from 3000 to 6000 cGy are presented. In order to evaluate direct radiation injury to gustatory tissues as a mechanism of taste loss, measurements of damage to specific taste structures in bovine and murine systems following radiation exposure in the clinical range are correlated to taste impairment observed in radiotherapy patients.

Mouse tongue mucosa has been used as a model to study dose responses to local irradiation. Although the irradiation procedures is less feasible and more time-consuming than e.g. snout irradiation, the tongue is the only location where a reasonable area of intraoral, multilayered epithelium in the mouse can be locally treated and scored, and a relatively small burden is imposed on the animal. In pilot experiments with external 300 kV x-irradiation just tolerated by the lip, the authors did not see critical damage to the tongue. In the present model, the onset of denudation was not correctly predicted by the normal turnover time of the tissue.

Interpretation of the relative GI 'toxicities' of cytotoxic drugs depends on the endpoint chosen. Histological assays of the dynamics of mitotic and necrotic cells in murine crypts revealed few apparently radical differences between individual drugs and between drugs and radiation. The microcolony assay of clonogenic cells reveals major differences between drugs in the ability of cells to maintain crypt integrity or to regenerate crypt-like structures, after doses that permit survival of the mouse to 4 days or more. Over the first week after treatment, survival time of the mouse as a function of drug dose also varies widely between drugs. All drugs used here resulted in gastrointestinal damage; whether that necessarily implies that animals die within one week of a gastrointestinal syndrome, synonymous with that for radiation, is very doubtful, and requires to be tested for each individual drug for which it is made.

Firstly, data are presented on the diurnal variation in the number of hypersensitive cells and secondly data on the repopulation kinetics of such cells in regenerating crypts after 9.0 Gy. Information on the location of the presumptive target cells susceptible to cell death (apoptosis) after various cytotoxic drugs is also presented. Published data using the microcolony assay for crypt survival (i.e. studies on clonogenic cells) are compared with these, and the differences between the hypersensitive cell population and the clonogenic cell population are highlighted.

The present paper describes some of the ways enterocytes adapt their normal patterns of development to cope with modest increases in crypt cell production rate. Preliminary results also show how disease affects some of these adaptive

processes and speculation made as to whether the effect could be used as a bio assay for cytotoxic drugs and radiation damage.

Male C57BLasup(t) mice of two ages, 3-5 months (young) and 14-15 months (old) were given 11 or 15Gy whole body irradiation at different times through the day. The mice were killed after 4.5 days and the number of surviving crypts per circumference of jejunum, ileum, transverse colon and descending colon were scored. These results show crypt survival in the small and large intestine of 15-month-old mice. In the ileum the maximum crypt survival was found at 04.00 h and the minimum at 08.00 h. In the jejunum and both regions of the colon the maximum crypt survival occurred at 16.00 h. The nadir of crypt survival after 15 Gy was at 04.00 h in the jejunum and at 20.00 and 24.00 h in the transverse and descending colon, respectively. In young mice, crypt survival levels were similar to those found in old animals except at 04.00 h. when survival in the jejunum and ileum fell to 0.0004+-0.0002 and 0.0007+-0.0004, respectively. The lowest crypt survival in the colon of young mice also occurred at 04.00 h and in all four tissues the greatest number of crypts survived irradiation at 24.00 h.

The authors have examined the influence of secondary infection, inflammation and the consistency and amount of faeces on the development of chronic radiation ulcers in rats. It is concluded that chronic ulceration is not always fatal but may be repaired if the faeces are soft and their volume reduced. However, this repair is not complete but leads to cystic colitis and repeated and progressive signs of transient rectal obstruction until fatal ileus occurs. From these and other experiments the authors conclude that the development of chronic radiation ulcer and of cystic radiation colitis in rats and in patients is the result of secondary mechanical damage to a susceptible atrophic mucosa and not the direct consequence of radiation damage to a specific target cell population.

Radiation-induced mitotic delay in mice was investigated at each cell position along the side of the crypt (position corresponding to different levels of maturation). From the results presented, it is shown that the duration of mitotic delay is shorter the closer the proliferative cells are to their last cell division in the proliferative hierarchy in the crypt and longest for cells situated where the stem cells are to be expected.

Data are presented from which it is concluded that the amount of glandular tissue in the submucosa at 6 months may be related to the residual increase in connective tissue component. If the connective tissue component continues to increase it could lead to further decreases in glandular tissues and thinning of the epithelium of the oesophagus. Significant atrophy of the submucosal oesophageal glands could have serious clinical implications.

10 Gy to the small bowel was the threshold x-ray dose needed to produce a significant influence of the percentage of crypts in fission (PCF), crypt cell proliferation (CCP), and intestinal crypt number (ICN). Generally, when ICN was rising after reaching a low point due to radiation injury, PCF and CCP were declining. The system appeared to recognize when ICN is approaching normality and therefore has a lessened need for crypt fission and CCP. This same pattern was seen during recovery of the intestine from an IP injection of mechlorethamine hydrochloride or cyclophosphamide. In contrast (St. Clair, 1985), the response to resection of 70% of the rat small bowel was as follows: total crypt number in the remaining ileum and jejunum showed no tendency to return to normal. CCP was increased, and PCF unchanged. These findings plus the decline in PCF with increasing age postnatal rats suggests that crypt density rather than total crypt number modulates PCF. Since there was a change in CCP of unirradiated duodenum, but no change in PCF, there is the suggestion that humoral factors are related to CCP, but that local factors regulate PCF.

It is concluded that although the major target in terms of radiation damage is undoubtedly the epidermis, the skin is a complex tissue made up of many inter-dependent components each of which may constitute an important secondary target. Damage to each component has been considered at the cellular level. The precise inter-relationships and interdependencies remain somewhat obscure. Even within

one site, the epidermis, a comprehensive cellular explanation of the various post-irradiation changes is difficult. Substantial bibliography.

Growing mouse vibrissae were investigated by light and electron microscopy to compare the effects of hydroxyurea (1500 mgkg{sup -1} intraperitoneally) and gamma radiation (10 Gy). In the case of the drug, specimens were obtained from 30 min to 9 days post-treatment. Irradiated specimens were taken at intervals up to 1.5 years post-irradiation. The morphological alterations were similar for both types of insult, but the time sequences of events were quite different. The post-irradiation recovery period was vastly extended compared with that of the hydroxyurea treated hair roots.

The authors have used mouse skin to test whether the LQ model fits the dose-fractionation response down to extremely small doses per fraction (0.1 Gy) and whether this response can be attributed entirely to a cell population of uniform radiosensitivity. The fit to the data was encouraging.

Interest is focused on the relative change in steepness and separation in dose of acute and late tissue response for various fractionation schedules. Dose-incidence curves generated from more than 100 patients drew the following conclusions: 1) Iso-effect doses for late effects using conventional and hypofractionation will result in significantly stronger acute reactions in the case of conventional fractionation. 2) The effect of proliferation during radiation does not necessarily reduce the tissue response. Conclusions from the dose-latency experiments were: 1) The latent period for a low incidence can be used to predict the latent period for any higher incidence of a certain effect. 2) Change in the dose is followed by a change in the time-scale of manifestation of damage, which implies a dose-dependent latency.

The present study was designed to measure cell survival and skin healing (lack of necrosis) after irradiation of different lengths of mouse tail. It is concluded that the field-size effect in this system, in terms of gross skin response, is reflected by similar changes in the survival of colony-forming cells, and that the effect may be caused by a difference in sensitivity of the cells.

The authors investigated the reactions of murine Langerhans cells to local (feet) and/or whole body 250 kV X-rays in vivo and measured the dose/response effects. The results led to the conclusion that LC density could be an indirect indicator of late dermal responses to radiation as well as a short term indicator of haemopoietic function and epidermal damage.

Repeated whole-body gamma-irradiations of Macaca fascicularis were performed with {sup 60}Co at 160 and 1.3 mGy min{sup -1} (2 Gy weekly, during 4 weeks). At the end of each exposure, skin explants obtained by punch biopsies were analysed during the primary culture. Kinetics of the first fibroblastic migration, fibroblastic proliferation and the fraction of multinucleated cells were recorded. At the lower dose-rate, even for the lowest delivered dose, irradiation tended to be more effective on cell outgrowth kinetics (cell migration and cell proliferation) than at the higher dose-rate, suggesting that a more important fraction of cells in the most radiosensitive phases of the cell cycle might be affected during the lower dose-rate exposure.

Clonal growth of primary cultures of pig fibroblasts was used to determine dose-effect relationships after in vitro cobalt-60 and in vivo iridium-192 irradiation. Radiation damage was assessed by analysis of growth kinetics.

A study has been carried out of the radiation response of keratinocytes from human skin, mouse skin and mouse tongue to 0-10 Gy of {gamma}-radiation, carried out in suspension at 20{sup 0}C. The Dsub(o)values for primary cultures of keratinocytes was similar to those obtained in vivo for mice, suggesting that this in vitro assay could be used to measure the sensitivity of keratinocytes treated with various cytotoxic agents. Sensitivity appears to change on subculturing and hence subcultures may be less appropriate for determining in vivo cell sensitivities.

Murine skin cells were labelled with [{sup 3}H]-TdR immediately after {sup 90}Sr-{sup 90}Y beta irradiation with 30 Gy, and animals killed at different time intervals. The number of labelled cells decreased exponentially with time, and no labelled cells were found after 20 days. No unscheduled DNA synthesis was present at the lethal dose range, except at a dose of 300 Gy. When beta irradiation was repeated with a dose of 4.7 or 11.8 Gy 3 times a week, 100% skin tumour incidence was obtained within 550 days. 1.35 Gy per exposure caused neither depilation nor tumour induction during 300 days, when tumour incidence was 23% after 4.7 Gy. With 27 Gy per exposure once a week, no tumour was induced in 300 days. The authors conclude that repetition of irradiation is necessary to obtain a high tumour incidence and that an optimum dose range per exposure exists of between 5 and 10 Gy.

This review, with substantial bibliography, concludes that the acute effects of radiation and cytotoxic drugs are a result of toxicity to the most sensitive of the germ cells, which in most cases are the differentiating spermatogonia. Long-term sterility or reduction in sperm production depends directly on killing of spermatogonial stem cells. For a variety of cytotoxic agents, the same relationship holds between the stem cell survival index and the prompt recovery level of sperm production (at 56 days), the maximal recovered level of sperm production, and the time required for fertility to return. It also appears that the spermatogonial stem cell is the target for long-term sterility in man following cytotoxic therapy. It is not known whether the delay in recovery is a result of this direct damage to the stem cell or an effect on another target cell in the tissue. Data obtained in both experimental animals and man indicate very little direct changes in the secretory cells and other stromal cells of the testis, and there is no evidence as yet that any alterations in these cells adversely affect sperm production or reproductive performance.

The results presented from rhesus monkey studies are comparable with the results obtained by Rowley et al (1974) after irradiation of human testes. They describe a very slow depletion of the human seminiferous epithelium after X-irradiation taking several months (0.25 Gy to 4.0 Gy and one fractionated dose of 2 x 2.0 Gy). They also note isolated clones which were thought to be derived from 'early differentiated spermatogonia which had not repopulated themselves'. All these features were found in the present study. In non-primate species the depletion of the seminiferous epithelium proceeds much faster.

The present study presents evidence of radiation-induced Sertoli cell damage in both the pubertal and adult rat. The indirect measurement of Sertoli cell function, serum follicle stimulating hormone (FSH), in general mirrored the changes seen in androgen binding protein (ABP), again indicating Sertoli cell dysfunction. Although FSH remained elevated in adult rats after 5 Gy and above and in pubertal rats after 10 and 20 Gy, the elevation was not as great as that observed in castrates. This suggests that FSH secretion was still inhibited by some factor. As ABP was reduced to near 'background' (castrate) levels after these high doses, suggesting Sertoli cell dysfunction, this may indicate that serum ABP levels may not adequately reflect all Sertoli cell functions. Alternatively FSH may have been inhibited by by Leydig cell androgens, which have been demonstrated to modulate, in part, FSH secretion. Although the Leydig cells were damaged, androgen secretion was not entirely reduced during the study. In general, FSH was elevated when severe damage to spermatogenesis was noted. Whether the changes were related to the absence of a specific spermatogenic cell type could not be determined.

Adult male Chinese hamsters were exposed to bilateral whole body irradiation with fast fission neutrons of 1 MeV mean energy (irradiation groups of 4 hamsters received doses of 0.25. 0.50 and 1.00 Gy). Animals were sacrificed after 20 days. Combination of the results with previous data obtained in the mouse led to the conclusion that spermatogonial stem cells are most radiosensitive while in a quiescent state and that they become most radioresistant during the transition from the quiescent to the active state. During the normal cell cycle radiosensitivity is likely to be intermediate.

The value and limitations of the following types of assay in assessing cytotoxic injury to bone marrow are reviewed: circulating blood cell counts, spleen colony-forming unit counts, in vitro colony assays, in vitro and in vivo assessment of the haemopoietic microenvironment, assay of the proliferative status of stem cells, assays of the cytotoxic damage resulting from acute, high and low dose-rate, and continual and partial-body irradiation, stem cell quality, distribution of haemopoietic cells in the marrow, stroma assessment, and the effects of cytotoxic chemicals.

The use of DS{sub 500} as a radioprotective agent for the haemopoietic system seems certain over the mid-lethal range of radiation doses. It has yet to be determined whether the shock-like syndrome associated with the higher doses of DS{sub 500} affects radioprotection. It is suggested that the earlier appearance of reticulocytes after irradiation, if DS-pretreatment was given, indicates an enhanced earlier recovery of erythropoiesis and haemopoiesis. The reticulocyte rise can be easily detected but the quantitation of this parameter is not yet sufficiently reproducible to be dependable; individual mice begin the reticulocyte rise and peak on slightly different days. Also the 'lysing-resistant' population of reticulocytes has not been morphologically identified, nor has the reason for this resistance been forthcoming as yet.

The authors have demonstrated changing sensitivities of CFU-S to inhibitor and stimulator (prepared from marrow regenerating after 4.5 Gy irradiation) as they progress through a developmental age structure and a differential production of, and response to, these factors in different radial zones of the marrow. The findings were compatible with the marrow being spatially and temporally organized for the regulation of haemopoiesis.

The authors describe experiments which attempt to elucidate the nature of haemopoietic stem cell and microenvironmental stromal cell interactions which might explain anomalies in explanations of the differential effects of radiation on HSC versus MSC. In particular, there is an attempt to demonstrate the existence of stromal niches.

In order to detect injury to stem cells which neither kills them nor inhibits their reproductive integrity, an assay method was used which measures the proliferative ability of irradiated bone marrow relative to unirradiated bone marrow, following transfusion into lethally irradiated recipient mice. Neither the proliferation factor nor the CFU-S number per femur recovered completely within one year after 5 Gy, and the number of CFU-S per femur was more suppressed than the PF.

This review firstly presents a brief description of the main components of the immune system (lymphoid tissues including nodes, thymus, spleen, G-I tract etc), and lists in outline the types of assays of function, unique probes and critical techniques presently used to investigate immune phenomena (use of highly inbred mice, immunodiffusion for detecting interaction of antigen and antibody, electrophoresis, radioimmunoassay, immunohistochemistry). The wide spectrum of radiosensitivities exhibited by the cell types of the immune system is then discussed and data presented in tabular form in relation to cell traffic, secondary lymphoid tissues such as spleen, lymph nodes and Peyer's patches, thymus, and to low dose augmentation in relation to tumours. Comparison is made of the immunological effects of cyclophosphamide and radiation.

The results after murine whole body irradiation are compatible with those reported in other literature. There was a decreasing spleen weight and viable spleen lymphocyte number on an equivalent schedule. The recovery of a normal antibody dependent cellular cytotoxicity (ADCC) after 20 days with an inversion during the 3rd week, was also compatible with data involving other immune cells, even if it is earlier than for NK cells. Note was also made of a different effect with 'low' doses (lower than 1.5 Gy) compared with the medium and high doses, suggesting different recovery mechanisms of the immune function of low doses, and a high radiosensitivity of the entire spleen-lymphocyte population at low doses.

After prior accidental irradiation (3 subjects) or experimental irradiation (3 monkeys) the results showed that in vitro irradiation with 4 Gy induced a significantly higher number of acentrics as compared with samples which had not received the prior irradiation. However, the number of dicentrics per cell was unchanged. A long time after irradiation in vivo, there was no elevated sensitivity in the fourth human subject. The higher radiosensitivity might suggest a chromosomal repair deficiency induced by prior irradiation in vivo. The experimental protocol could be used as an indicator of radiosensitivity following radiotherapy, chemotherapy or occupational exposures.

The bone marrow stromal cells have been implicated as an integral part of the haemopoietic microenvironment, which is responsible for the in vivo regulation of adult haemopoiesis Stromal stem cells give rise to adherent colonies of fibroblast-like cells in vitro. This CFU-F assay allows the study of functional characteristics and qualitative and quantitative responses of the stromal cells. Experiments to determine CFU-F concentrations in femoral bone marrow pooled from 3 to 8 normal adult mice gave results which were not reproducible. From one experiment to another, the mean CFU-F concentrations varied from 0.5 to 4 CFU-F 10{sup -5} bone marrow cells even though all the experiments were performed with identical culture conditions according to a standard procedure for CFU-F assay. In this study the authors found that the variability was due to important individual variations in the concentration of CFU-F between different animals (mice).

Acute irradiation was carried out at 1.5 Gy min{sup -1}, split-dose experiments were performed at 1.5 Gy min{sup -1} to a total dose of 6 Gy, as a single dose or two equal fractions split by up to 4 h, and dose-response curves were prepared over a range of 8 dose-rates from 0.141 Gy min{sup -1} to 0.0017 Gy min{sup -1}. The results show that CFC-C and CFU-S differ considerably in their capacity for repair. CFU-S are incapable of radiation damage repair: the acute survival had no shoulder, there was no recovery between doses in the split-dose experiment and the cells showed no change in sensitivity when the dose-rate was lowered. This contrasted with the results for CFU-C for which the acute survival curve had a shoulder, there was split-dose recovery and cellular sensitivity decreased with decreasing dose-rate, all suggestive of the cells showing repair capacity. However, it is CFU-S survival which is thought to be directly related to animal survival at 30 days, a parameter which has been shown to increase with decreasing dose-rate. The repopulation data suggests that differences in parameters other than initial cell kill may be responsible for this phenomenon.

This paper reports the results of measurements of Cs-137, Cs-134, Ru-103 and Ru-106 + Rh 106. The study started at the end of May 1986 and lasted up to the end of November 1986. The region where the samples are taken is very mountainous and the grass is used for cattle pasture and forage production. 19 samples were analysed during the season. 2 figs, 3 tabs, map.

A summary of the measurements carried out in Italy is presented. The following items were monitored: air, fallout, rate of exposure, soil, grass, vegetables, fodder, milk, cheese, eggs, meat and fish. The data have been transferred to a data bank, containing now the information on more than 100,000 measurements. 6 figs, 1 tab.

Operating experience of nuclear fuel cycle facilities has proved that the performance and availability of key equipment largely depend on the reliability of its construction materials. In general, the materials of construction have performed well in accordance with the design criteria of equipment. In some cases, however, materials failure problems have been encountered, the causes of which are related to their corrosion and mechanical degradation. In response to the growing interest in these topics, the IAEA convened the Technical Committee Meeting on ''Materials Reliability in the Back-End of the Nuclear Fuel Cycle'' at its Headquarters from September 2 to 5, 1986. This Technical Document contains the 15 papers presented during the Meeting. Material aspects of the following fields of the back-end of the nuclear fuel cycle are covered: interim and long-term storage of spent fuel; final disposal of spent fuel; storage and

vitrification of High Level Liquid Wastes (HLLW); long-term storage of High Level Wastes (HLW); and spent fuel treatment. Refs, figs and tabs.

In order to qualify corrosion resistant materials for high level waste (HLW) packagings acting as a long-term barrier in a rock salt repository, the corrosion behaviour of the preselected materials Ti 99.8-Pd, Hastelloy C4 and two unalloyed steels was investigated. The resistance of the materials to general corrosion, local corrosion and stress corrosion cracking was examined under postulated accident conditions in the repository by long-term immersion tests of up to 4 years duration and electrochemical methods. The parameters investigated were different salt brines, temperatures of 90 deg. C, 170 deg. C and 200 deg. C as well as a gamma radiation field of 10/sup 3/Gy/h (10/sup 5/rad/h). Among the materials studied, Ti 99.8-Pd exhibited the highest corrosion resistance. This material corroded at a very low rate (<l{mu}m/a) both with and without gamma radiation, and proved to be resistant to local corrosion and stress corrosion cracking. Hastelloy C4 exhibited a good general corrosion behaviour ({le}{mu}m/a) but was susceptible to crevice corrosion, and pitting corrosion occured at 200 deg. C. Under gamma irradiation i.e. in the presence of strong oxidants (e.g. H/sub 2/O/sub 2/, C10/sub 3/-bar) the susceptibility of Hastelloy C4 to local corrosion increased and strong pitting and crevice corrosion was observed at 90 deg. C. The electrochemical studies confirmed the tendency of this material to local corrosion. They show that the stability of the protective passive layer is greatly reduced with increasing temperature. The two unalloyed steels (fine-grained steel and cast steel) were resistant to local and stress corrosion cracking in the absence of gamma radiation. However, the steels must be sufficiently protected against gamma radiation. An unalloyed steel seems to be the most promising material for a long-term HLW-packaging. 10 refs, 10 figs, 1 tab.

Several Ni-Cr(-Mo) alloys (HASTELLOY C4, INCONEL 625, SANICRO 28, INCOLOY 825, INCONEL 690) were tested by electrochemical methods to characterize their corrosion behaviour in chloride containing solutions at various temperatures and pH-values in respect to their application as canister materials for final radioactive waste storage. Especially, HASTELLOY C4 which proved to have the highest corrosion resistance of all tested alloys was tested by the following electrochemical methods: (1) Poteniodynamic measurements to determine the characteristic potentials, passive current densities and critical pitting potentials. (2) Potentiostatic measurements in order to evaluate the duration of the incubation period at various potentials. (3) Galvanostatic measurements in order to characterize critical pitting potentials. As electrolyte 1 m H/sub 2/SO/sub 4/ was used, as parameters temperature, chloride content and pH-value were varied. Variation of temperature gives the following results: an increase in temperature leads to an increase of the critical passivation current density, the passive potential bandwidth decreases slightly and the passive current density increases with rising temperature. The addition of different chloride contents to the H/sub 2/SO/sub 4/ solution shows the following effects: the critical passivation current density and the passive current density increase with increasing chloride concentration and both, the critical pitting potentials and the pitting nucleation potentials, shift towards negative values. As third parameter the pH-value was varied. As expected, an increase of the pH-value extends the passive region to more negative values, the passive current density decreases. The variation of the pH-value does not affect the critical pitting potential. All tested alloys showed a clearly limited resistance against pitting corrosion phenomena. 5 refs, 8 figs, 1 tab. (Abstract Truncated)

The decision is taken in the USSR to build additional independent spent fuel storage facilities for 10 or more years of NPP operation. The longer the time of SFA storage, the more severe are the requirements for fuel element cladding integrity and for all fuel assembly and storage components safety. Investigations of zirconium alloy and some steel corrosion under storage pool conditions indicated the possibility of long-term safe storage in water pools. However, model experiments indicated the probability of significant steel corrosion acceleration due to radiation exposure. 8 refs, 2 figs, 5 tabs.

In the framework of the development of containers for the final disposal of radioactive waste in salt deposits DWK conceived the Pollux Cask System. This cask system is highly flexible in so far as it is capable of bearing extremely different types of waste such as integral fuel elements, consolidated rods, HTR-pebble elements, consolidated structure materials, solidified high active waste etc. The Pollux cask system is characterized by an anticorrosive coating of Hastelloy C4 which is applied to by surface welding. With regard to its long term behaviour comprehensive corrosion tests on Hastelloy C4 were performed in Q-brain. This report presents a survey on results of these corrosion tests; especially recent results of long term integral tests (lasting about two years) on two cask models will be reported about. Moreover investigations on surface corrosion and local corrosion in dependence of the temperature will be reported about in order to demonstrate the limits of application of the anti-corrosive coating. 16 figs.

Storage tanks for concentrated fission product solutions are made of Z 2 CND 17-12 (AISI 316 L) stainless steel. The solution temperature is cooled below 60 deg. C and permanent stirring of the medium keeps the insolubles in suspension preventing the formation of wall deposits. This stainless steel was selected after a number of corrosion tests conducted ''in situ'' in the tanks of nuclear facilities and in radioactive fission product solutions prepared in the laboratory. All these tests demonstrated a superior localized corrosion resistance under radioactive deposits for AISI 316 L steel, when compared to AISI 304 L steel. Laboratory tests were also performed up to 100 deg. C in fission product solutions containing ferric ions (up to 20 g.1/sup -1/). Under these conditions, more severe than nominal operating conditions, 316 L steel exhibits some risks of intergranular attack. The operating conditions adopted, and the experience gained in France over the past 30 years, clearly vindicate the choice of 316 L steel. 8 figs, 6 tabs.

DIN Standard Huey testing has been performed in boiling 14.4n nitric acid during 5-15 periods (240-720 h) for selection of appropriate nitric acid resistant materials for nuclear fuel reprocessing applications. The paper describes the testing process during which the intermediate and final results of metal loss by dissolution are directly transferred from the balance to the computer, stored and activated - besides material properties data - for documentation purposes. Further routine evaluation of these experiments includes metallography in cross-section and surface microscopy to look after uniform and local metal dissolution phenomena and their relationship to the bulk structure. A large variety of materials have been tested this way through the last years. It was shown how sensitively the chosen testing conditions are able to differ between materials of the same nominal composition AISI 304L/Material No. 1.4306 in different contents of residual elements. Especially, for the purest electroslag-molten steel (ESU) results of parameter studies concerning the influence of sensitization, cold deformation, grain size and sheet thickness (in respect to end grain attack) are given. Within an attempt to define faster methods of corrosion testing, e.g. to differ within a group of materials of similar composition, but different corrosion behaviour, electrochemical tests in heated nitric acid were performed under potentiostatic conditions. The necessary electrochemical equipment and the results of its application by potentiostatic tests on AISI 304L in above mentioned three chemical compositions at 1250 mV, 14n HNO/sub 3/ are presented. 5 refs, 5 figs, 2 tabs. (Abstract Truncated)

Spent fuel reprocessing involves various operations in which nitric acid is used at relatively high concentrations and at temperatures up to the boiling point. The choice of Z 2 CN 18-10 stainless steel (AISI 304 L) is a satisfactory solution to mitigate corrosion problems when using solutions with a maximum concentration of 8N, up to the boiling point. Above this concentration, since the corrosion rate is significantly higher, it is better to use Z 2 CN 25-20 stainless steel (Creusot-Loire's URANUS 65). Despite these advantages, these stainless steels are not immune to intergranular corrosion, if the medium containing oxidizing species or ions (such as Cr VI, Pu VI or higher concentrations of FE III) places the material in transpassive conditions. In

this case it is recommended to use silicon-rich stainless steel (4% Si) Z 1 CNS 17-15 (Creusot-Loire's URANUS S1N). Whatever the steel grade used, however, when cross-sections of plates, pipes, or forgings are exposed to the corrosive medium, the development in the rolling direction of end-grain attack (tunnel corrosion) can hardly be prevented. End-grain attack most usually spreads from non-metallic line inclusions caused by working, forging and rolling operations (sulphides being the most dangerous inclusions). This form of corrosion may also occur in oxidizing media, along zones segregated in chromium, molybdenum or silicon, and/or along second-phase alignments such as ferrite or {sigma}phase. A very-low carbon material with good inclusion cleanliness can be obtained by a specially designed argon vacuum process. The proper control of the preparation and transformation processes yields, for this material, semi-finished products perfectly suitable for use in nitric acid media with respect to hazards in developing end-grain attack, regardless of the presence or absence of oxidizing species or ions. 10 figs, 1 tab.

In Tokai Reprocessing Plant, several problems on the main process equipment have occurred due to the corrosion of the austenitic stainless steel. Under these circumstances, the plant operation was stopped for a long intermittent period in order for us to investigate the corrosion conditions and take necessary measures such as repair or replacement of failed equipment. In this paper, such problems and measures are summarized together with the description of the corrosion behaviors in reference to the dissolvers and acid recovery evaporator in the plant. 2 refs, 13 figs, 3 tabs.

AISI 430 stainless steel can be cathodically protected in highly oxidizing solutions. The freely corroding potential of this stainless steel in such solutions is transpassive. In the protecting process this potential is lowered from the transpassive to the passive zone by applying potentiostatic techniques. The chemical structures of the surface films formed during the various stages of this potential shift were investigated by X-ray and Auger electron spectroscopies combined with Ar/sup +/ ion sputtering for depth profiling and by scanning electron microscopy. The shift is accompanied by two distinct phenomena: a) Increase of the concentration ratio of the oxidized to the metallic states of the iron and of the chromium present in the film. This implies that films formed in the passive zone are thicker than those formed in the transpassive one, a fact which is also revealed by the Auger depth profiles. b) Formation of a layered structure in the passive zone which is characterized by chromium surface segregation in the film. Three layers were detected. The layer at the metal film interface is composed of Cr/sup +3/ oxide whereas the two layers above it are composed of mixed iron and chromium oxides with the iron being primarily of Fe/sup +2/ type in the intermediate layer and of Fe/sup +3/ type in the outer one. 7 refs, 6 figs.

The concept of spent fuel storage in Czechoslovakia is based on storage for 5 years followed by transport to the reprocessing plant. General considerations on fuel assembly integrity during its prolonged pool storage and transport of spent fuel container were given taking into account the possible effects of fuel burnup increase and load following mode of reactor operation. 6 refs, 4 tabs.

Austenitic stainless steels display satisfactory behaviour in reprocessing facilities. However, certain failures are occasionally observed and usually ascribed to corrosion in oxidizing nitric media capable of bringing these materials close to or within the transpassive range. Zirconium does not present this drawback and helps to solve corrosion problems in these particularly aggressive conditions for stainless steels. Zirconium generally displays an outstanding general corrosion resistance in nitric acid media. In practice, however, its use in reprocessing facilities leads to the consideration of certain factors that may either restrict its application, or should be closely investigated. The most important among these are: fluoride content of the medium; nitrogen content of the metal; formation of possible insoluble compounds despite very low ionic release rates; stress corrosion cracking observed only in some severe laboratory testings. It was decided to use zirconium in the new

facilities at La Hague for most of the weld-fabricated equipment treating boiling nitric solutions and for a number of specific process units (for example, reactors containing sulphides in acidic media). A total of 80 tons of zirconium will be employed, and 5,500 meters of piping circuits are being installed with this material. This was achieved through the development of semi-finished products (plates, pipes, etc.) with properties adapted to the construction of the large weld-fabricated units of nuclear chemistry. Shaping, welding and inspection specifications have been developed. Finally, the choice and development of zirconium were facilitated by the use of zirconium-stainless steel junctions allowing the connection of a zirconium unit to a stainless steel piping system. 7 refs, 22 figs, 5 tabs.

Reliability of materials at the back-end of the fuel-cycle is a subject of permanent interest for countries that have nuclear reactors. Safety, at that stage, should be understood as the system of physical barriers to prevent radioactivity release into the environment. Those barriers must be reliable during extended periods, e.g. 50 to 100 years for interim spent fuel storage, and over 1,000 years for permanent waste disposal. The first physical barrier is the fuel itself, namely pellets and cladding. Independently of the selected intermediate storage (dry or wet storage) fuel integrity, decay heat extraction and appropriate shielding, must be guaranteed. Two PHWR nuclear reactors are now operating (ATUCHA-I: 345 MWe; EMBALSE: 600 MWe) and one more is being built (ATUCHA-II: 745 MWe), 700 additional MWe of nuclear origin, are planned to be connected to the electrical power distribution nets during the next 15 years. For intermediate spent fuel storage, wet technology has been selected. At present, 8200 CANDU type spent fuels are in the EMBALSE pools and 4300 ATUCHA-I type ones are in the ATUCHA-I pools. A thorough control and maintenance program on materials that can stay under water during long periods, is being investigated. Materials used for high level waste containment, as lead, are being characterized. Herewith is described the management of fuel pools, chemical and radiochemical controls, studies for the proper selection of structural materials and for a high level waste disposal container. 9 refs, 3 figs, 7 tabs.

Choice of proper materials of construction for various applications in reprocessing of Fast Reactor fuels plays a vital role from considerations of safety and economics. A brief mention of process followed particularly for the reprocessing of mixed carbide fuel is made. The plant is classified into various functional zones based on severity of radiation and chemicals for the choice of materials such as highly radioactive cells, radioactive laboratories, low and high level waste storage areas, off-gas treatment section, etc. For each of the areas, the criteria for the selection of material is defined and based on that probable candidate materials are identified. Work carried out on corrosion studies related to the conventional and electrochemical dissolver and its components is described. Need for development of a specific code for the fast reactor fuel reprocessing industry is stressed. The paper also describes the facilities available in the Chemical Metallurgy Section for the corrosion studies and spells out the programme in the Centre for development of material needed for this part of the nuclear fuel cycle. 4 refs, 1 fig.

The French vitrification process for solidifying high-level radioactive waste which has been under industrial application since 1978, is briefly mentioned. This technique involves glass melting at 1,150 deg. C, using an induction heated metallic vessel. The molten glass pouring is controlled by a thermal gate, which is also heated by induction. Two types of vessel are in use. Both are remotely removable and disposable to permit replacement at regular intervals. The technical criteria that the materials have to meet are described. The behaviour of the materials has been investigated using the industrial experience gained in the AVM facility during 8 years of operation, as well as with operation of a prototype for the new vitrification facilities under construction at La Hague. A short description of the use of these materials is also presented. 5 figs, 2 tabs.

The Belgian R and D programme on the disposal of high level radioactive waste has been focused on the qualification of deep argillaceous formations for HLW disposal, because they have a number of inherent attractive characteristics and also because they are sufficiently abundant to cover the Belgian needs. A large number of corrosion resistant materials as well as some corrosion allowance materials have been tested. The laboratory test program included accelerated tests as well as exposure tests in simulated repository conditions. Initial ''field'' experiments have been performed in a near surface clay quarry. However, in order to obtain realistic corrosion rate estimates corrosion experiments with simultaneous monitoring of the clay environment parameters have been started in a 230 meters deep underground laboratory constructed in the Boom clay formation at Mol. Two types of experimental devices have been designed. In the first type coupons are mounted on an internally heated tubular holder and are directly exposed to the solid clay. In a second type of test a purge gas is used to extract corrosive products from the clay and circulate them subsequently over a number of metal coupons. Relevant parameters such as pH and Eh are continuously monitored for evaluating the evolution of soil agressivity after the initial chemical and mechanical disturbance of the clay, caused by the operations required for the introduction of the experimental devices. 3 figs.

This paper presents a newly developed method to evaluate reliability of complex systems composed of independent three-state devices. The method is demonstrated with the aid of a hypothetical example of a complex system. In addition, the impact of unit (i.e. three-state device) open and short mode failure probabilities on bridge network reliability is shown.

For a linear-elastic cylinder with an axial through crack subject to internal pressure loading, stress intensity factors and crack opening areas were calculated by the finite element method. Wall thickness and crack length were varied for constant mean radius of the cylinder, thus varying the shell parameter lambda with 2.5 <lambda <= 23. The computed stress intensity factors depend on lambda as well as on R/t and show considerable differences to solutions based on shallow shell theory even for very short cracks. The range of validity of these solutions is discussed. Starting from the observation that the energy release rate for a semi-infinite crack is finite, a simple interpolation formula is given that retains the proper asymptotic behaviour for very long and very short cracks. Crack opening areas are given and compared to an approximate analytical formula from the literature. Some general limitations of the validity of the present results, particularly the required minimum lengths of the cylinder, are discussed.

An effective method is developed for estimating failure rates for plant-specific risk studies from scarce data. A new technique is used for determining empirical prior distributions first, and individual component estimates are then determined as posterior distributions. This parametric robust empirical Bayes (PREB) method is applied to globe valve data and compared to other methods with a variety of numerical data. The results demonstrate the superiority of the PREB method over alternative techniques, especially for small samples. Connections to Stein's and fiducial estimation are discussed, and methodological recommendations are given for generic or design-specific risk studies and failure rate coupling studies.

This paper considers the joint and conditional probabilities of a number of (not necessarily identical) components which are all influenced to variable degrees by a single common extraneous factor. Explicit formulae are derived for these probabilities for specific values or statistical distributions of the common perturbing factor.

The patent describes a hybrid preheat/recirculating steam generator for nuclear power plants. The steam generator utilizes recirculated liquid to preheat incoming liquid. In addition, the steam generator incorporates a divider so as to limit the amount of recirculating water mixed with the feedwater. (U.K.).

A scanning device, particularly for viewing above the core of a nuclear reactor, has links pivoted together with means limiting relative movement in one sense. At least one link carries a transducer, preferably ultrasonic, for viewing. There may be two transducers arranged to view in different directions. The transducers may be mounted in a removable module. A deployment arrangement may have a vertical hollow mast down which the links can be pushed to engage a deflect element to reach an arm from which the links can extend as a cantilever.

A sludge collection system for a vertically oriented nuclear steam generator is provided with an upwardly open chamber for receiving separated liquid and incoming feedwater that contain sludge particulates. A plurality of sludge collecting containers are positioned within the chamber and include a top rim encompassing an opening leading into the interior of each container. Generally flat perforated covers are positioned over each container such that a gap is formed between the cover and the adjacent top rim. Particulate material in the water entering the container can settle within the container because of relatively stagnant conditions. Sludge agitation and removal means are provided for remotely cleaning the containers. The sludge collection system components are sized to permit retrofitting this system into existing steam generators.

A nuclear steam generator comprises a feedwater header ring disposed in the upper portion of the steam generator shell which header has a plurality of J-shaped discharge nozzles, some of which are in fluid communication with the upper portion of the feedwater ring header while others are in fluid communication with the lower portion of the feedwater ring header. Those in fluid communication with the lower portion of the feedwater ring header have a discharge elevation lower than those in fluid communication with the upper portion of the feedwater header so that, during low feedwater flow operation, feedwater is preferably removed from the lower portion of the feedwater header in order to reduce stratification of feedwater therein.

A steam generator which utilizes a primary fluid to vaporize a secondary fluid is provided with an open flow channel and elevated discharge nozzle for the introduction of secondary fluid. The discharge nozzle is positioned above a portion of the inlet line such that the secondary fluid passes through a vertical section of inlet line prior to its discharge into the open channel.

A retaining pin mounting assembly for nuclear reactor guide tubes including a pin having a one end portion for disposition within a bore in the upper core plate of a reactor, while the other end is to extend through a bore of the guide tube flange and has a threaded region for threadedly receiving a nut provided with a locking cap. The pin has a flange and a shank of a diameter smaller than the bore within guide tube flange and the nut has a skirt adapted to engage the flange and having an inner diameter larger than the shank such that an annular space is formed around the shank. Radial flow apertures extend through the skirt of the nut so as to permit coolant flow through the annular space around the pin shank in order to prevent corrosion by differences in the concentrations of the reactor coolant from that around the pin shank.

The problem of crack stability in piping systems is analysed in the case of fully ductile conditions. The criterion is based on the concept of the net section approach for which adequate experimental confirmation is present. The overall crack instability is based on the analysis of the modification of the local stiffness matrix in the cracked area. A eta parameter (related to the tearing instability, T modulus) is used. Typical data are presented.

A nuclear reactor fuel pin is passed by a nip roller assembly, between a source of radiation and a detector and a measure of the lengths of successive fuel pellets in the pin is derived from the output of the detector (eg the peaks between pellets) and the pin speed. The pin is moved in steps past a further detector of naturally occurring radiation from the fuel to obtain an indication of the enrichment level at positions spaced along the pin. A comparison of the detector outputs with control values enable a pin to be accepted or rejected.

Information on 17 producing companies (name, address, contact name) and the types of fuel produced is tabulated. The fuels are listed under reactor type. The availability of fissile and fertile materials, cladding, enrichment and performance of the fuels is given. The companies listed are from Europe, North America and Japan. (U.K.).

The patent concerns grids for sub-assemblies of nuclear reactors. The grid comprises a plurality of cells, with each cell receiving one fuel pin. The fuel pin is engaged by two inwardly directed projections within the cell, the projections in successive grids along the pins being displaced by 120{sup 0} in the same sense. Such an arrangement facilitates dismantling of the irradiated sub-assembly prior to reprocessing of the fuel. (U.K.).

The patent relates to fluid operated devices for moving articles. The machine may be used in filling a nuclear fuel canister with fuel pellets where there is a tendency for out of squareness of pellets to produce a jam condition readily cleared by a modest force. (U.K.).

The patent describes a method of producing a sintered body of nuclear fuel material. The method relates specifically to the production of uranium oxide powder/binder mixtures, which can be compacted to provide green bodies for subsequent sintering. The production entails the preparation of the surface of the U0{sub 2} particles in two steps, whereby a predetermined amount of hexavalent uranium is caused to precipitate from solution onto the particle surfaces. The particles are then ready for contact with an appropriate reactant to form a fugitive binder.

Continued attention to fuel performance has over the years improved fuel reliability and reduced fuel related failures. But further improvements can still be made by increased attention to reactor operating and maintenance methods, as well as to quality control during fuel fabrication.

Sipping can identify the fuel assembly with a leaking rod, but to identify immediately which rod is leaking you need ultrasonics. Exxon Nuclear has developed just such an ultrasonic system, called ''Ultratest''. Probe design features are given, together with details of the data collection and processing.

Babcock and Wilcox has developed a fully automated ultrasonic system that identifies failed fuel rods in a fraction of the time required by sipping or conventional ultrasonic techniques, the company claims.

Work which underpins the complex phase changes occuring in uranium dioxide fuel during and after reactor operation, is described. Areas covered include: oxidation studies, structural chemistry, methods for the determination of oxide fuel structures and an outline of future work. (U.K.).

Progress in the development and in the benchmarking of the COMETHE code is illustrated in different areas, mainly in relation to steady-state fuel behaviour. The topics discussed are clad corrosion at high burnup and its thermal and mechanical consequences; behaviour of burnable toxic fuel; low temperature microstructure dependent fuel swelling; ovalization of the cladding and creep collapse; pre- and post-bump fission gas distribution; and prediction of clad failure.

Detailed examinations have been made of the pore size distributions in fuel taken from three irradiation experiments carried out in the materials test reactors at AERE, Harwell. The fuel was irradiated at temperatures in the range <400- approx. = 1900C to burn-ups of between approx. = 3 and approx. = 2700 MWd/tU. Porosity measurements were made from optical and scanning electron micrographs using a Magiscan image analyser. The data obtained from these experiments and from similar work reported in the literature have been used to draw general conclusions regarding the mechanisms of in-pile sintering of UO{sub 2}. Several models for in-pile sintering are reviewed and where possible their predictions are compared with observation. The paper concludes with some recommendations to be considered in future models.

The paper describes the development and sample use of a computer code which automates both the Monte Carlo and response surface approaches to probabilistic fuel performance modelling utilising the SLEUTH-82 deterministic program. A number of the statistical procedures employed, which have been prepared as independent computer codes, are also described. These are of general applicability in many areas of probabilistic assessment.

Literature data suggest different behaviour for short-lived fission products swept by carrier gas from the centre of operating annular UO{sub 2} fuel and the surface of solid UO{sub 2} fuel. To determine directly these release differences, the authors have irradiated, in the same test assembly, one element containing solid UO{sub 2} pellets with four 1 x 1 mm surface slots and one element containing UO{sub 2} pellets with a central hole 2 mm in diameter. The linear power range was 17-57 kW m{sup -1}; thermocouples monitored operating temperatures. He-2% H{sub 2} carrier gas swept short-lived fission products from both elements past independent spectrometers for identification and measurement. Our first results show the releases from the gap- and centre-swept elements are power-dependent from 17-57 kW m{sup -1}, with a release ratio ranging from 3 to 10. The centre-swept element always shows the higher release. At 57 kW m{sup -1}, the peripheral temperatures for the centre- and gap-swept fuel were 990 {sup 0}C and 960 {sup 0}C, respectively; the temperature of the inner surface of the annular fuel was 1700 + - 50 {sup 0}C. The centre-swept element shows a larger released iodine inventory in fuel and sheath areas with access to the carrier gas.

The patent describes a beam alignment system for laser welding work pieces, such as fuel rod grids for nuclear fuel assemblies. The apparatus for performing various laser-machining comprises a beam alignment system including alignment target means, as well as means for emitting, directing and focusing the laser beam. (U.K.).

An elongate metal needle is used to detect blockage in a throughbore in a nuclear fuel pellet or other article. The pellets are fed along a tube and horseshoe magnets support the needle so that the pellets pass along the tube with the needle in the pellet bores. When a blockage is sensed, feed interrupted and a switch is operated to energize magnets to rotate the tube so that the defective pellet passes through a rejection slot. Visual indicators indicate when a blockage has occurred.

Apparatus for testing the orientation of an end face of a pellet to pellet axis includes a laser which sends a beam of radiation through a beam splitter to an apparatus in which a pellet has a mirror held to an end face and the radiation is reflected by the mirror to form a beam leading to a sensor. If the end face is not at right angles to the pellet axis, the reflected beam is angularly displaced from the incident beam and diverges to provide an indication at the sensor. A circular aperture may cut off the beam from the sensor at a predetermined angle of divergence to provide an indication of when the pellet end face is at a limit of acceptable orientation. The predetermined angle can be adjusted by changing the aperture diameter. A disc can replace the aperture.

The apparatus comprises a bolster slidable within a tubular body and having a cross-sectional configuration conforming to that of the tubular body. The bolster carries a fluid-actuated former which is urged outwardly against a localised region of the tubular body to impress into a die-recess an external pad on the body. Additional fluid-actuated means may operate in directions perpendicular to that of th former to support the body.

Particulate material, eg. fuel pellets for a nuclear reactor, is moved along a spiral path during drying by vibration of the path structure. Preferred apparatus comprises a hollow cone with a conical flight defining a path of travel having an inlet for the material and an outlet. The cone is heated by a radiant heater within the cone which itself is vibrated or oscillated about column. A cone provides an air space in which air can circulate and leave by

convection through chimney. The flight may have a pile providing a fibrous surface for engaging the material.

Articles such as nuclear fuel pellets are loaded stackwise into an elongated container such as a fuel can by feed mechanism comprising two wheels which form a bite, one wheel being driven by a stepper motor and the other being an idler. A retractable stop pin in the feed passage provides a datum position for each successive stack of pellets.

A transfer system for a nuclear fuel container within a nuclear reactor facility includes a transport car for transporting the fuel container through a transfer tube between a reactor containment handling pool and a spent storage pool. The system includes mechanisms for automatically pivoting the fuel container from its horizontal transport mode to its vertical, fuel loading-unloading mode when the fuel container enters one of the pools. The pivot mechanisms include slotted brackets mounted upon the fuel container, and pivotable pick-up bars for engaging the brackets of the fuel container. As the transport car moves past the pick-up bars, the brackets of the fuel container engage the bars whereby the latter pivot so as to in turn cause pivoting of the fuel container through means of trunnions. Reverse movement of the transport car causes reverse pivoting of the container from the vertical to the horizontal mode and ultimate disengagement of the brackets from the pick-up bars.

The paper concerns the proceedings of a seminar on operating procedures for abnormal conditions in nuclear power plants, organised by the IAEA, and held in Munich, June 1986. Emergency operating procedures for design basis accidents are discussed, along with accident management, plant safety, operator training, and safety goals. (U.K.).

The control rooms of all French 900MWe PWRs are undergoing modification. Controls are being repositioned and colour-coded according to function to simplify the work of the operator and reduce the chances of error.

A detector is used to monitor the fluid coolant pool of a nuclear reactor and operates by detecting short-lived fission or activation products by the Cerenkov radiation they produce. The detector includes a Cerenkov detector head connected by an optical fibre bundle extending through pool to a photosensitive detector. The output signal from detector is passed to a comparison unit and processing unit for examination, evaluation and presentation of output signal data for suitable use e.g. detection of failed fuel or changes in density of the pool. An optical test unit monitors the photosensitive detector.

A position indicating system for detecting the position of a metallic member e.g. a nuclear control rod, comprising sensing means e.g. transformer operatively associated with the member for producing a position representative signal which varies with changes in the temperature of the member is temperature compensated. Temperature monitoring means e.g. coil coupled with winding are associated with another member to monitor its temperature and produce a signal representative thereof. Combining means are connected to receive the position representative signal and the temperature signal to produce a signal which represents the position of the member compensated for changes in temperature of this member.

The patent describes a method to determine the relative position of a control rod within the core of a nuclear reactor. The invention relates to a temperature compensating position indication system for an element [such as a rod] which is moveable in a direction along the axis. The temperature compensation is controlled by a temperature sensitive sensor whose output signal contains a temperature variable offset component. (U.K.).

The patent describes a moderator control apparatus for controlling the reactivity of a nuclear fuel assembly. The apparatus controls the nuclear reactivity by varying the volume of the moderator/coolant associated with the fuel rods of the assembly. At the same time a burnable poison gas is added to improve fuel utilization, which allows for lower fuel enrichments. (U.K.).

Following the accident at the Chernobyl nuclear power plant, a proposal has been made that the International Atomic Energy Agency (IAEA) should carry out a programme of reactor assessments and inspections to ensure that the plant is competently run. The 13 proposals for improving safety that arose from the recent IAEA meeting in Vienna about the events at Chernobyl are listed. They also propose international collaboration on many points. This article draws attention to the difficulties in achieving international cooperation. Comparison is made with the case of international air and marine transport and an attempt to get an agreement to reduce emissions of acid rain precursors by 30%. The essential requirements for international regulation are stated. Four specific activities that could be covered are discussed. These are inspection of operating plant, enforcement of minimum standards for routine emissions, establishment of design standards and establishment of post-accident procedures for international co-operation.

The safety of UK reactors is considered in the light of the accident at Chernobyl. The steps taken to ensure that similar accidents could not occur in the UK are mentioned. However, in addition to efforts to prevent accidents, emergency arrangements have been made and these are explained and the chain of command for nuclear installations emergency arrangements given. (U.K.).

There are several matters to be considered carefully in relation to a more realistic assessment of contamination which might result from wet deposition of radionuclides released in a nuclear accident. The use of radar data showing detailed spatial and temporal development of rain, coupled with surface wind fields, gives a better indication of when and where material released would encounter precipitation and be brought down to the ground. An understanding of the meteorological situations and dynamic movement of air aids the estimation of what processes are likely to be operative in incorporating pollutants in rainfall at ground level. The occurrence of intense rainfall is clearly revealed by radar and indicates strong convergence and possible concentrated deposition. Thus, in a real accident the radar system could be most valuable in identifying potential hot spots of deposition.

The geochemistry of the REE (rare earth elements) in oceanic sediments is discussed, based mainly on samples from DSDP Holes 530A and 530B, Leg 75, and Hole 525A, Leg 74. The proposed mechanisms for incorporation of the REE into the marine carbonate phases are adsorption, chiefly onto the carbonate minerals and on Sc, Hf, and Ta-rich FE-Mn hydroxide flocs as carbonate coatings. The Ce anomaly of marine carbonate was used as an indicator of paleo-ocean water redox conditions: the bottom water of the Angola Basin was in a reducing condition in the Cretaceous. At ca. 54 My, the South Atlantic water condition became oxidizing, similar to the present seawater redox condition. This change was related to the improvement of circulation due to the widening of South Atlantic and the subsidence of water circulation barriers such as the Walvis Ridge and perhaps the Romanche Fracture Zone. The REE abundances and patterns of younger sediments in the Angola Basin (YSAB) are very similar to those observed in NASC, PAAS, and ES sediments. The YSAB REE abundances and patterns may represent the average REE distribution of the exposed African continental crust. The strong resemblance of REE distributions of YSAB, NASC, PAAS and ES suggests thorough REE mixing from different sources and the uniformity of the average crustal compositions of different continents: Africa, North America, Australia, and Europe.

A summary is given of the results obtained in an NRPB study, commissioned by the Department of the Environment, of the radiological impact resulting from the movement of low and intermediate-level radioactive wastes between conditioning plants and storage or disposal facilities. Much of the work required the use of theoretical assessment procedures but, where possible, the results of radiation surveys and work studies were applied.

The inquiry into the proposed Sizewell nuclear power station has also brought into question the way in which risk is assessed. In the United Kingdom the Nuclear Installations Inspectorate (NII) ensures the safe operation of nuclear

power plants and decides how much money needs to be spent on reducing the risk of fatal accidents. The two methods of assessing a value for a life are explained and their relative merits discussed. The Health and Safety Executive (of which the NII is part) uses a human capital approach. The Nuclear Radiological Protection Board uses a risk-reduction method which gives a much higher figure. It is suggested that a common basis for assessing risk should be adopted.

The work describes the validation with field data of a finite element model of material transport through aquifers (FEMA). Field data from the Idaho Chemical Processing Plant, Idaho, USA and from the 58th Street landfill in Miami, Florida, USA are used. In both cases the model was first calibrated and then integrated over a span of eight years to check on the predictive capability of the model. Both predictive runs gave results that matched well with available data.

Risk values are often used to evaluate the safety of the nuclear fuel cycle. Some UKAEA figures are quoted for the annual risk of death. This article explains how risk values are derived and what they mean. Risk is defined, the history of risk assessment covered briefly and then hazard identification, hazard analysis, consequence analysis and risk evaluation are mentioned. It is concluded that no nuclear plant is perfectly safe, improvements can always be identified during the risk assessment process. (U.K.).

The present review is a technical assessment of present and possible future uranium mining and conversion (the principal processing step) in South Australia. Specifically, it examines the implications of mining and conversion for the natural (physical and biological) environment. Enrichment is not considered.

Both experimental and analytical studies have been performed on the temperature coefficient of reactivity in a light-water moderated and reflected core loaded with highly-enriched-uranium fuel, which was constructed in the Kyoto University Critical Assembly (KUCA). The temperature effect on reactivity was measured for the range of 20 {similar_to}70 deg C to investigate separately the effects of (1) the fuel pitch (H//sup 235/U atomic ratio) and (2) the core shape on this physical quantity. The experimental data were analyzed with use of the SRAC code system. The calculated eigenvalue k/sub eff/ agreed with the measured one within 0.5 % in the C/E ratio for both the 2- and 3-dimensional diffusion calculations. The experimental data were approximately reproduced by both the eigenvalue and perturbation calculations. It was found that the contribution of the core region was negative to the temperature coefficient of reactivity, whereas that of the reflector region was positive. The synthesis of these contributions made the temperature coefficient negative in total. The degradation of moderation was the main contributor in the core region, whereas the decrease in the neutron absorption in the reflector region. The positive contribution of the reflector region became larger as the H//sup 235/U atomic ratio became smaller and the core shape became more slender.

This investigation deals with seismic response analysis considering the nonlinear support-gap characteristics. The dynamic restoring force-deformation relation for a pipe-support system is assumed to be a simplified bi-linear model. This paper highlights particularly the effect of support stiffness and gap size upon the maximum response of the piping system subjected to random excitations including seismic motions as follows: (1) Displacement and velocity are suppressed by the growth of support stiffness, however, acceleration response frequently provides higher pulsive peaks. (2) The effects of support stiffness and gap size upon piping response are summarized by the ''f*-z* diagram'' proposed in this study. This diagram can be drawn only through the ratio of the natural period of piping and that of supporting structure system. (3) The ''F*-Z* diagram'' proposed in this study can be obtained only through the response for the least feasible condition where the natural period of piping coincides with that of supporting system.

Purpose: To moderate temperature change of a reactor and prevent thermal shocks upon reactor scram. Constitution: Temperature measuring points are disposed with a predetermined gap along the height in the high temperature plenum of a nuclear reactor. Then, signals from each of the thermometers are introduced into a rotational number controller for coolant recycling pumps. With such a constitution, it is detected for the height in the high temperature plenum formed above the reactor core in the reactor container reached by the low temperature coolants reached. The detection signals are sent to the rotational number controller for the pump to control the number of rotation of the pump in accordance with the flow rate of the low temperature coolants in the high temperature plenum. This enables to prevent rapid change in the temperature. (Ikeda, J.).

Purpose: To provide a waterfeed function also upon accident in addition to cooling function upon reactor isolation as a system for normal ordinary use. Constitution: A condensate tank is connected with a vacuum pump and the pipeway therefrom is branched to the inside and the outside of the reactor container. Exhaust gas from the vacuum pump is sent to the reactor container upon reactor isolation in a case where the pressure of the reactor container is not increased, whereas if the pressure is increased, the exhaust gas is discharged to the outside of the reactor container. In this way, since the feedwater is maintained by the cooling system upon nuclear reactor isolation even in medium or small-scaled rupture accident, it is no more necessary to in effectively actuate other emergency core cooling system. Further, it is possible to prevent the development of radioactive contaminations to the pump or turbine area. (Kamimura, M.).

Purpose: To reduce stress corrosion cracks, etc. in pipeways by injecting hydrogen in proportion to the flow rate of reactor feedwater during plant operation. Constitution: A deviation between a signal from a hydrogen injection amount generator and a flow rate setting signal from a function generator is determined to conduct integration control by the deviation. As a result, proportional control can be made for the feedwater flow rate. Further, in the case of oxygen, an injection flow rate control valve is controlled. In this case, an actual injection amount is selected as a setting signal in the course of increasing the hydrogen injection amount, while a signal obtained by way of a primary delay element and a loss time element is selected as a setting signal in the course of the decreasing step. In this way, since hydrogen can be injected continuously in proportion with the feedwater flow rate even during plant operation, sensitivity to stress corrosion crackings in the pipeways, etc. can be reduced. (Takahashi, M.).

Purpose: To rapidly remove metal sodium deposited to remain on the surfaces of equipments and prevent alkali corrosions, etc. Method: For inspecting or repairing equipments used in liquid metal sodium, it is necessary to wash and remove metal sodium deposited to remain on the surfaces of the instruments. In view of the above, when the surfaces of the equipments deposited with metal sodium are washed with a gas mixture comprising wet nitrogen gas and gaseous carbon dioxide, Sodium hydroxide formed at the surface of metal sodium by the reaction with water are directly brought into reaction with gaseous carbon dioxide into a swollen sodium carbonate. Further, the reaction can be promoted by repeating the pressure change such as pressurization - atmospheric pressure - reduced pressure, by which gaseous carbon dioxide can be supplied rapidly even to fine gaps. This enables to prevent alkali corrosions, etc. (Takahashi, M.).

Purpose: To effectively remove cruds deposited to fuel assemblies by a ultrasonic cleaning method in a state where a channel box is attached. Constitution: A fuel assembly is cleaned or washed within a fuel pool filled with water. The assembly attached with a channel box as it is moved downwardly from above the pool by way of a fuel exchanger and the lower end of the assembly is seated on a receptacle seat. Ultrasonic vibrations are applied to the outside of the channel box while displacing the ultrasonic vibrator along the fuel assembly to strip the cruds from the fuel assembly and the cruds are sucked and

removed by the suction pump. This enables to safely and effectively remove cruds deposited to the fuel assembly. (Takahashi, M.).

Purpose: To suppress the deposition of ferrous oxalate precipitates to decontaminants and improve the removing property of corrosion products. Method: Boric acid is prepared as a decontaminating solution in a decontaminating solution vessel, injected into a recycling path for the decontaminating solution by driving a recycling pump and recycled under heating by a heater. After conducting decontamination for a predetermined of time, reduction of light transmittance of the solution due to the generation of suspension products caused by the formation of ferrous oxalate is detected by a light transmittance measuring device and aqueous hydrogen peroxide is injected into the decontaminating solution. Then, since the resultant precipitates of ferrous oxalate are oxidized into ferric oxalate and dissolved in the solution, deposition of the precipitates to decontaminates can be prevented and removing performance for the corrosion products becomes excellent as well. (Sekiya, K.).

Purpose: To remove cobalt ions without cooling reactor coolants. Method: Fibrous potassium titanate (K/sub 2/O center dot nTiO/sub 2/; n = 1 - 5) are prepared from molten products of potassium titanate compounds comprising TiO/sub 2/, K/sub 2/O and K/sub 2/MoO/sub 4/, from which potassium is removed to obtain titania hydrate (TiO/sub 2/ center dot nH/sub 2/O; n = 0.5 - 2). The titania hydrate is used instead of ion exchange resins. Since the ion exchange capacity of the titania hydrate exhibits satisfactory performance under high temperature and high pressure (lower that 500 deg C, 500 atm), it is no more necessary to cool the coolants below 70 deg C as in the conventional ion exchange resins. (Ikeda, J.).

In fiscal 1985 (from April 1985 to March 1986), the number of accidents, failures, etc. in the nuclear power plants, reported by the owners to the Agency of Natural Resources and Energy according to the law, is total of 19; the number per plant is 0.6. Of the 19, 4 are of automatic shutdown during operation, 8 of manual shutdown during operation, and 7 detected during the periodical inspection. Then, concerning the causes, 6 are due to inadequate manufacturing, to inadequate construction, 11 to inadequate maintenance, and 1 to other inadequate managements respectively. In any of the 19, there were no influences of radioactivity on the environment around the site. (There were 28 slight accidents in addition.) (Mori, K.).

Purpose: To measure the gadolinium content in pellets in a non-destructive manner and rapidly by using a relatively simple device. Method: A plurality of pellets of known gadolinium contents different from each other are prepared. A constant current is passed through two points in each of the pellets and a voltage drop therebetween is measured to determine a resistance value between the two points. Then, a graph for the calibration curve of the gadolinium content and the resistance value is prepared. Then, the resistance value is determined for a pellet with unknown gadolinium content, which is corresponded to the graph of the calibration curve to determine the unknown gadolinium content. (Ikeda, J.).

Purpose: To reduce the size of a reactor core and, thus, that of an entire nuclear reactor by decreasing the number of control rods without impairing the reactor shutdown function in an FBR type reactor. Constitution: The scram operation is carried out by a scram operation signal. Even in a case if the scram signal should fail to be outputted, coolant temperature rises due to the abnormality of the reactor and, when it rises above a curie point, the curie point electromagnet of the curie point electromagnet mechanism is demagnetized. Then, magnetic adsorption between this mechanism and the adsorbed plate is released causing an inside extension tube to fall thereby releasing the engagement between a latch filter and a handling head, by which a control rod is inserted to the inside of the reactor core to surely conduct scram operation. In this way, by providing both of the function, i.e., the scram operation due to the scram signal and the scram operation in a case if the scram signal should fail to be outputted by some or other reason, control rods and appendant

mechanism for a reserved reactor shutdown device are no more necessary thereby enabling to reduce the size of the nuclear reactor. (Horiuchi, T.).

Purpose: To scram control rods by processing signals from a plurality of temperature detectors and generating abnormal temperature warning upon occurrence of abnormal temperature in a nuclear reactor. Constitution: A temperature sensor comprising a plurality of reactors each having a magnetic body as the magnetic core having a curie point different from each other and corresponding to the abnormal temperature against which reactor core fuels have to be protected is disposed in an identical instrumentation well near the reactor core fuel outlet/inlet of a reactor. A temperature detection device actuated upon detection of an abnormal temperature by the abrupt reduction of the reactance of each of the reactors is disposed. An OR circuit and an AND circuit for conducting OR and AND operations for each of the abnormal temperature detection signals from the temperature detection device are disposed. The output from the OR circuit is used as the abnormal temperature warning signal, while the output from the AND circuit is utilized as a signal for actuating the scram operation of control rod drive mechanisms. Accordingly, it is possible to improve the reliability of the reactor scram system, particularly, improve the reliability under a high temperature atmosphere. (Kamimura, M.).

Purpose: To enable to confirm the solenoid integrity with no actual scram thereby improve the reliability in a scram function test performed during reactor operation. Constitution: The function test for the scram pilot valve device is conducted by operating two solenoid valves each by system so that the reactor does not undergo actual scram. That is, the valve body is actuated while driving only one of the solenoid valves, the vibration waveforms are detected and compared with a previously stored reference vibration waveforms by the monitor device. If there is any abnormality, a warning signal is outputted from the valve monitor device. Even of the air release port of one of the solenoid valves is opened, since the air release valve of the other of the solenoid valves is closed, air is not released during the test for one of the solenoid valves and the reactor can be operated continuously with no scram. (Yoshihara, H.).

Purpose: To improve the adaptable property of operation patterns capable of power change to an assumed low power state and rapid power change to optional power states with no undesired effects to the power distribution. Method: Power conditioning control rod groups having neutron absorbing performance which is set lower in the lower portion and greater in the upper portion are divided into a plurality of subgroups. Upon power change, power control rods of the plurality of subgroups are successively displaced between the fuel withdrawal position and full insertion position. Accordingly, even in a case if power changes in the course of the designed low power state, only the first subgroup can, for example, be inserted fully, by which distortion in the vertical power distribution in the intermediate power state can be overcome. (Horiuchi, T.).

Purpose: To arrange control rod assemblies in a high conversion type water cooled reactor so as to attain uniform power distribution and greatly reduce the risk of leading to reactivity accidents. Constitution: A plurality kind of control rods of different diameters are arranged such that those control rods of greater diameter with higher control rod worths are inserted into the control portion of a fuel assembly and those control rods of smaller diameter with lower control and worths are inserted at the peripheral range. Accordingly, the power at the central portion of the fuel assembly where the void reactivity coefficient becomes positive, a great amount of voids are generated and the power is increased can be suppressed more as compared with the peripheral portion thereof thereby flattening the power distribution. Further, it is possible to suppress the fuel can temperature of fuel rods disposed in the central position and reduce the reactivity accidents. (Horiuchi, T.).

Purpose: To remove movable portion and improve the reliability by the direct control to coil. Constitution: Coils are disposed vertically at a predetermined

interval to the outside of a control rod drive guide tube and each of the coils is adapted to be directly controlled. The coils are arranged at such an interval that a plunger laps over the vertically adjacent coils. In the case of moving the plunger upwardly, a coil just above the coil that attract the plunger is energized while the coil attracting the plunger so far is denergized. Then, the plunger is pulled up to an aimed position by repeating the procedures. In the case of moving the plunger downwardly, the procedures are conducted in the manner opposite to the above. (Kawakami, Y.).

Purpose: To automatically calculate each of the data just after the measurement of the reactor power distribution, thereby obtain measurement errors. Constitution: The inside of the reactor is vertically scanned by or movable incore neutron flux detectors and measured signals as the result of dual measurement at an identical point within a predetermined time interval are stored. The following automatic calculations are executed based on the standardized values (Ai1, Ai2) for a plurality of dual measured values: (1) error for each point i (Xi); ti = (Ai1-Ai2/Ai) x 100 (%) where Ai = (Ai1 + Ai2)/2, (2) standard deviation ({sigma}) for the time sequential group at each point i; {sigma} = ({Sigma}Xi2/(n-1))/sup 1/2/; (3) standard deviation ({sigma}) to a single measurement; {sigma} = {sigma}/2/sup 0.5/, A device for outputting (Xi, {sigma}, {sigma}) obtained as above is disposed. It is possible to recognize the error distribution in the vertical position of the reactor core and recognize the error due to detectors based on {sigma} and {sigma}. (Kamimura, M.).

Purpose: To reduce impact shocks without changing the margin to the scram time while preventing unnecessary increase in the scram rate. Constitution: Gases within a scram driving gas vessel are adjusted by way of a gas pressure adjusting mechanism due to the changes in the coolant pressure of a nuclear reactor pressure vessel thereby maintaining the scram time always constant irrespective of the fluctuations in the coolant pressure of the nuclear reactor pressure vessel. That is, a gas pressure adjusting mechanism is put between the pressure vessel and the nitrogen vessel to increase the pressure in the nitrogen vessel by the increase in the pressure of the pressure vessel. Further, the pressure in the nitrogen vessel is reduced due to the lowering in the coolant pressure thereby maintaining the scram time substantially constant irrespective of the changes in the pressure of the pressure vessel. In this way, it is possible to prevent increase in the scram rate to bring about impact shocks, as well as improve the reliability, integrity and the safety. (Kamimura, M.).

The earthquake observation has been examined at a cylindrical type cavern hydroelectric power station of 15 m in diameter, 22 m in depth in rock mass in purpose of evaluating the earthquake resistance of semi-underground nuclear power plants. The behavior of the cylindrical cavern has been analysed by fourty-three observed seismic waves. And following results were obtained. (1) Ratios of cavern buttom maximum accelerations to cavern top maximum accelerations are concentrated in the range from 1/2 to 1. This shows that the accelerations are declined at underground. (2) The decline ratios of on-ground spectrum amplitude to the underground at the earthquakes of less than 100 km epicentral distance with shorter predominant periods are generally larger than these at the earthquakes of more than 100 km epicentral distance with longer predominant periods. (3) The peak periods of normalized response spectrum at underground tend to be longer as the epicentral distances are longer. This phenominons of underground are similar to the on-ground.

In case of reactor accidents, it is desirable that a stack gas monitor for high-concentration mixed radioactive rare gases measurement should indicate a value directly proportional to the exposure rates in the environment. In a stack monitor based on a new method which enables the easy estimation of exposures in the environment, the radioactive rare gases at a release source is partly allowed to flow through a limited space where two detectors are mounted, one having a flat {gamma}-ray energy response and the other having a sensitivity dependency with energy. The detector having a flat response is made by a high-

pressure argon filled ionization chamber covered with thin copper filter and the other is made by a xenon filled one using the same way. Accordingly, a special unit of exposure rate ({mu}R/h center dot m/sup 2/ center dot l/h) and an average {gamma}-ray energy of the released mixed radioactive rare gases are measured by use of the two detectors, thereby providing the exhaust-stack gas monitor with a capability of directly predicting exposure rate in the environment. The new method is suitable for the emergency-use stack gas monitor.

A report by Nuclear Safety Commission to Prime Minister, concerning alteration in the experimental fast reactor installation (the employment of J2 fuel assembly and hence J2 core) in PNC's Oarai Engineering Center, is presented; PNC's technical capabilities and safety after the alteration are confirmed. The examination made by NSC's Committee on Examination of Reactor Safety for safety confirmation is described: safety design (mechanical design, nuclear characteristic of the core, thermal characteristics, dynamic characteristic), fuel handling facility, exposure doses in normal operation, accident analysis, and siting. (Mori, K.).

A simple model was developed to evaluate the effect of the radial power profile on the thermo-hydraulics in the core during reflood phase of loss-of-coolant accident in PWRs. It was incorporated into REFLA code, a reflood analysis code. The model assumes that the fluid mixes completely among subchannels and additionally that the fuel temperature is not affected each other among fuels. This model is featuring no three-dimensional treatment for the evaluation on effect of the radial power profile. The model improved the predictability of clad temperature and gave a better prediction than a method which is generally used in the safety analysis. The model predicted a poorer core cooling in high radial power region than data. The error of the prediction increased with the increase in radial power ratio. These indicates the conservativeness of the model on the maximum clad temperature prediction. The reason of the conservativeness is due to the neglection of the heat transfer enhancement by two-dimensional effect in high power region.

Purpose: To improve the earthquake proofness of reactor core constituent elements, as well as to enable the reduction of seismic loads on the radial support structures of the reactor core in an FBR type reactors. Constitution: In this invention, proper vibration of neutron shielding bodies disposed to the outer circumference of an FBR type reactor is made higher for the neutron shielding member constituting the outer layer. If the weight of the neutron shielding body for each of the layers is equal with each other, this can be attained by increasing the bending rigidity greater for the neutron shielding body at the outer layer. (Horiuchi, T.).

The placental transfer of /sup 3/H-retinoic acid in vitamin A deprived and vitamin A supplemented pregnant female rats was studied on 20th day of gestation and compared with /sup 3/H-retinyl acetate. Radiolabelled compounds were administered to pregnant mothers orally in groundnut oil six hours before sacrifice. The distribution of radioactivity of the two compounds was studied in maternal intestine, liver and plasma and fetal brain, heart liver lung and placenta. The transfer of /sup 3/H-retinoic acid across placenta was restricted as compared to that of /sup 3/H-retinyl acetate which may explain the reason why retinoic acid does not support fetal growth.

The metabolism of injected [/sup 3/H] PteGlu in hepatectomized rats was studied. Significantly higher radioactivity was found in all folate derivatives of regenerating liver. The results confirm the hypothesis according to which the decrease of endogenous polyglutamate content of regenerating liver might be ascribed to greater utilization rather than to lower synthesis of these coenzymes.

The paper entitled 'global anomalies' was presented to the workshop on 'Supersymmetry and its applications', Cambridge; United Kingdom, 1985. Global anomalies are anomalies under diffeomorphisms or gauge transformations that are

not continuously connected to the identity. The use of space-time global anomalies in superstring theory is demonstrated.

The paper was presented at the workshop on 'Supersymmetry and its applications', Cambridge, United Kingdom, 1985. Six theorems on characteristic classes and continuous cohomology are described, in connection with the theory of anomalies.

The paper which addresses the question 'can theories with anomalies be quantized' was presented at the workshop on 'Supersymmetry and its applications', Cambridge, United Kingdon, 1985. The quantum theoretical model of Weyl fermions interacting with the Yang-Mills field is considered. The author presents a realization of the Gauss law anomaly in terms of the canonical formulation of the quantum model, and discusses some specific proposals for the functional integral presentation of it. (U.K.).

A superspace analysis of the supercurrent and of the Adler-Bardeen current in supersymmetry is described. The paper was presented to the workshop on 'Supersymmetry and its applications', Cambridge, United Kingdom, 1985. In regularization by dimensional reduction, two distinct composite operators corresponding to the above currents are constructed, and it is shown how their different anomalous behaviour arises. (U.K.).

The paper was presented to the workshop on 'Supersymmetry and its applications', Cambridge, United Kingdom, 1985. The contents of the paper includes: 1) Chern-Simons terms and conformal supergravities, 2) conformal supergravity in d=3 is equal to super-Chern-Simons terms, 3) Chern-Simons terms in d >= 74, and 4) axial anomalies in N=1 and N=4 conformal supergravity. (U.K.).

The purpose of the 'Mini-introduction to strings' was to convey the flavour of string theory while giving no very precise formulae. The paper was presented at the workshop on 'Supersymmetry and its applications', Cambridge, United Kingdom, 1985. The topics described include: massless point particle moving in Minkowski space on a null geodesic, quantization of the string, the non-supersymmetric string in 26 dimensions, and computation of non-linearities in string theories. (U.K.).

The paper on superstring theory was presented to the workshop on 'Supersymmetry and its applications', Cambridge, United Kingdom, 1985. The classification of supersymmetry theories in ten dimensions is reviewed, and some of the salient properties of the five superstring theories that appear to be consistent are described. The structure of the light-cone-gauge field theory of superstrings is reviewed along with comments about possible alternative approaches. Finally, two-dimensional action principles for superstrings and their quantization are also discussed. (U.K.).

The status of calculations in string perturbation theory at the one-loop level is reviewed. The paper was presented to the workshop on 'Supersymmetry and its applications', Cambridge, United Kingdom, 1985. The subject is discussed under the topic headings: loops of open strings, closed-string loop amplitude, multi-loop amplitudes, one-loop chiral gauge anomalies, gauge invariance of tree diagrams, one-loop anomaly, and anomaly cancellations in the low-energy theory. (U.K.).

Both the gravitational and gauge field sectors of the d=10 superstring, including the Chern-Simons terms, may be obtained from the purely gravitational bosonic string in d=10+dim G via a spontaneous compactification on the group manifold G with <Hsub(mnp)> the parallelizing torsion. The Kaluza-Klein relation between the coupling constants {alpha}'g{sup 2} approx. kappa{sup 2} is that of the heterotic string. Consistency of the Kaluza-Klein ansatz is essential, and reduces the symmetry from Gsub(L)xGsub(R) to Gsub(L).

The paper was presented at the workshop on 'Supersymmetry and its applications', Cambridge, United Kingdom, 1985. Super-string theory is discussed under the following topic headings: the functional approach to the string amplitude,

Rieman surfaces, the determinants {Delta}ub(epsilon)(1) and {Delta}ub(epsilon)(2), Green's functions, total amplitude, and divergence analysis. (U.K.).

Exactly solvable locally supersymmetrical {sigma}models are discussed. The paper was presented to the workshop on 'Supersymmetry and its applications', Cambridge United Kingdom, 1985. Some aspects of the Wess-Zumino term are examined, followed by a derivation of the critical dimension formula for a Neveu-Schwarz-Ramond type string moving in the product of a d dimensional Minkowski spacetime times a group manifold. (U.K.).

The two-dimensional supersymmetric non-linear sigma models are examined with respect to the heterotic string. The paper was presented at the workshop on :Supersymmetry and its applications', Cambridge, United Kingdom, 1985. The non-linear sigma model with Wess-Zumino-type term, the coupling of the fermionic superfields to the sigma model, super-conformal invariance, and the supersymmetric string, are all discussed. (U.K.).

The Green Schwarz covariant superstring actions are construct-ed as conformally invariant superspace {sigma}models. The paper was presented at the workshop on 'Supersymmetry and its applications', Cambridge, United Kingdom, 1985. Flat super-space geometry, the Brink-Schwarz action for the super-particle, Siegels superparticle action, the Green-Schwarz covariant superstring action, and the light cone reduction of the heterotic string, are all discussed. (U.K.).

A local gauge covariant formulation of free strings is given and their interactions are examined. The paper was presented to the workshop on 'Supersymmetry and its applications', Cambridge, United Kingdom, 1985. The point particle, the bosonic string, oscillator formalism, and the gauge covariance formulation of the free string, are all discussed. (U.K.).

It is shown how in string theory, all of spacetime physics emerges from local Weyl invariance of the string. The paper was presented at the workshop on 'Supersymmetry and its applications', Cambridge, United Kingdom, 1985. Strings propagating in background fields, quantized string, string equation of motion, supersymmetric string, and the heterotic string, are all discussed. (U.K.).

The ideas and achievements of the harmonic superspace approach to extended supersymmetry is reviewed. The paper was present-ed to the workshop on 'Supersymmetry and its applications', Cambridge, United Kingdom, 1985. The definitions and the main properties of the harmonic variables and the analytic superspace in the case N=2 are given. The off-shell formulations of the N=2 matter multiplets in harmonic superspace are described, including the N=2 supersymmetric {sigma}models. N=2 supersymmetric Yang-Mills theory and N=3 supersymmetric Yang-Mills theory are also discussed. (U.K.).

The paper entitled 'Renormalization of supersymmetric Yang-Mills theories' was presented to the workshop on 'Supersymmetry and its applications', Cambridge, United Kingdom, 1985. The subject is discussed under the following topic headings: invariant and non-invariant regularization schemes, Ward identities and Wess-Zumino consistency conditions, N=2 super Yang-Mills with matter, and N=4 super Yang-Mills. (U.K.).

The derivation of a low energy hadronic effective Lagrangian from quantum chromodynamics (QCD) or supersymmetric (SUSY) QCD is discussed. The paper was presented to the workshop on 'Supersymmetry and its applications', Cambridge, United Kingdom, 1985. The Lagrangian is obtained as a low energy approximation of N {yields} infinity {sigma}SUSY QCD under the assumption that the chiral symmetry of the original theory is spontaneously broken. (U.K.).

Recent results on supersymmetry in a fixed Anti de Sitter (AdS) background geometry are summarized. These results include i) required modification of the generators of the O(3,2) isometry group in the AdS Wess-Zumino model, ii) the one-loop renormalization structure of this model, showing that the special 'naturalness' properties of flat space supersymmetry do not extend to AdS, and

iii) a non-perturbative Lehmann spectral representation. Open problems suggested by recent work are emphasized.

A new formulation of d = 11 supergravity is discussed which has local SU(8) invariance. It is indispensable for constructing the consistent truncation of this theory to N = 8 supergravity. The nonlinear aspects of such a truncation play an important role in analyzing its (residual) symmetries and in determining the interactions of the resulting low-energy theory.

The review is given of work on the construction and classification of N=2 Maxwell-Einstein Supergravity theories (MESGT), study of the underlying algebraical and geometrical structure of these theories, and their compact and non-compact gaugings. The paper on MESGT was presented to the workshop on 'Supersymmetry and its applications', Cambridge, United Kingdom, 1985. (U.K.).

The article describes how the 2b field theory and the II B string might be compactified, not only to a flat four-dimensional space-time, but with Su(3) x U(1) x U(1) gauge symmetry, N=2 supersymmetry - and even an Su(2) group in the background. The paper was presented at the workshop on 'Supersymmetry and its applications', Cambridge, United Kingdom, 1985. An N=8 theory in four dimensions is construct-ed which is the first gauged maximal supergravity theory to have a stable solution with a zero cosmological constant. (U.K.).

The paper entitled the 'Structure of Kahler manifolds in the N=2 vector multiplet - supergravity couplings' was presented to the workshop on 'Supersymmetry and its applications', Cambridge, United Kingdom, 1985. The subject is discussed under the following topic headings: N=2 vector and super-gravity multiplets, Lagrangian for N=2 supergravity coupled to {Lambda}ector supermultiplets, Kahlerian structure of scalar fields, and flat potentials and duality invariance. (U.K.).

The article is concerned with the way in which boundary surfaces in space-time may affect the divergence properties of a supersymmetric quantum theory incorporating gravity. The paper was presented to the workshop on 'Supersymmetry and its applications', Cambridge, United Kingdom, 1985. Boundary-value formulation of quantum supergravity, general form of surface counterterms, supersymmetry and surface terms, and surface partners for volume counterterms, are all discussed. (U.K.).

The energy properties of models with Einstein plus generic quadratic curvature terms, as well as purely quadratic theories, are investigated using supergravity embedding methods. It is shown that the generic models have indefinite energy, except for the R+{beta}{sup 2} case which has some stability domains. The vanishing of supercharge in conformal supergravity is also demonstrated. The apparent conflict be-tween indefiniteness of energy and its expression as the square of a supercharge is resolved through the indefiniteness of the fermionic Hilbert space metric. Fin-ally, some related aspects of and speculation about higher dimensional models involving quadratic terms suggested by string theory are presented.

Euclidean superalgebras in 3<=D<=10 are considered in some detail. For D=8,9,10 they are real, for D=3,7 complex and for D=4,5,6, quaternionic. The operations relating Euclidean and Minkowski SUSY for 3<=D<=10 are described.

Polycrystals of Zr have been deformed in tension at temperatures between 77 and 900K. The yield stress and the activation volume are dependent on temperature. Dislocation structure in specimens deformed at 77 and 500K is reported. Possible mechanisms explaining the temperature dependence of the yield stress are discussed.

Measurement of the residual stress distribution in the wall of Zircaloy 4(R) tubes produced by tube reducing followed by a stress relief anneal reveals a large compressive circumferential stress and somewhat smaller compressive axial stress on the inner wall. Annealing for one hour at 600 and 800 degrees C substantially reduces the level of stress in the tube wall, but the compressive

stresses remain measurable after such anneals. The analysis of the data permitted determination of the principal axes of the residual stress distribution from which it was found that the principal axes of stress nearly coincide with the principal directions of the tube at high stress levels. The maximum effective stress level observed was near the yield stress of the material.

Pronounced cyclic softening occurs from the start of testing in commercial-purity zirconium, while only slight cyclic softening occurs in high-purity zirconium. In both cases, the cyclic softening is associated with a decrease in the effective stress as determined from the shape of the hysteresis loops. The occurrence of this cyclic softening is associated with an increase in the mobility of the screw dislocations, and with the formation of dipolar walls. The observations indicate that an important portion of the hardening produced by interstitial solutes in zirconium is associated with an increase in the Peierls stress for the glide of the screw dislocations.

The phenomena of softening and hardening in metals due to chemical and structural lattice defects was investigated. The paper was presented to the International conference on the strength of metals and alloys, Montreal, Canada, 1985. The study determined the influence of the type of lattice defect on the flow stress of {alpha}-iron between 40K and 335K. Experimentally, the tensile properties of pure and N-doped {alpha}-iron were examined in the wide temperature range, and the results were compared with similar tensile measurements after irradiation with fast neutrons at different temperatures (20,145,210 and 250K). (U.K.).

The paper on the 'Precipitation effects and creep fracture in type 316 weld metal' was presented to the International conference on the 'Strength of metals and alloys', Montreal, Canada, 1985. The notch bar rupture and the creep crack initiation behaviour of a 316 weld metal was examined, and the influence of the transformation products on the creep fracture processes was assessed. The results suggested that only delta-phase formation initiates creep cracks in type 316 weld metal. (U.K.).

The microstructural development of TiN dispersion hardened 20% Cr-25% Ni stainless steel during primary creep at 160 MPa, 1123 K is described. It is shown that work hardening is dominant up to strains of approx. 3%, and that the hardening is due to the same mechanisms as have been identified in other dispersion hardened materials at low temperature, but at a rate reduced by concurrent recovery. At higher strains the recovery controls the deformation, and itself depends on the internal stress distribution which arises during creep because of the spatially inhomogeneous dislocation density. The creep characteristics therefore depend on the mutually interdependent behaviour of all the components of the dislocation substructure.

The basic concepts of both classical and quantum mechanical theories of channeling radiation are presented. The theories developed are discussed separately in low, medium and high energy regions.

The paper reviews the results obtained from theoretical studies of the above-barrier particle interaction with crystal atoms. It is shown that in the motion of relativistic electrons and positrons in a crystal at a small angle to one of crystallographic axes quantum effects should manifest themselves in scattering; the radiation spectrum of above-barrier electrons has a maximum in the low frequency region and a high radiation intensity at the maximum; and the mean square of the multiple scattering angle in the crystal appreciably exceeds that in amorphous targets.

Measurements of electromagnetic radiation have been performed in the range up to 5 MeV for channeled 1038.5 MeV positrons in a diamond crystal, 2 mm thick, along the (001) plane. The intensity spectrum shows small maxima at photon energies of 0.8 and 1.1-1.2 MeV, the positions of which are in agreement with the calculated positions of acoustic, transverse optical and longitudinal branches of diamond

lattice vibrations in the case of electromagnetic conversion of positrons on phonons.

The present paper reviews the results obtained for the influence of channeling and over-barrier motion on the relativistic electron and positron radiation in the crystal at different frequencies. The predictions of the Born theory of coherent radiation in the crystal are compared with those of the theory of radiation in channeling and over-barrier motion.

High linear polarization of gamma radiation from channeled electrons in diamond is reported.

New results on the experimental investigation of the electron in a diamond crystal, obtained at the Tomsk synchrotron, are presented. The experimental data are systematized in such a way that it allows observation of a transition from axial to planar channeling and the variation of a maximum position in the radiation spectrum at planar channeling with the electron energy change. A comparison of the spectra of the coherent bremsstrahlung radiation and radiation at planar and axial channeling is performed, and the radiation losses in angular cone 1/{gamma} are obtained.

This report presents the results of experimental investigations of the electron {gamma}-radiation characteristics of thick tungsten single crystals (0.29 and 0.64 mm) obtained on the Tomsk synchrotron. A comparison of the coherent bremsstrahlung radiation spectra (CBS) with the calculation was done for the various orientations of a single crystal. The spectral and orientational {gamma}-radiation characteristics under channeling have been obtained. A technique of the crystal targets orientation on internal beam of the synchrotron has been described.

The spectra of 1035 MeV positron radiation in diamond were measured in the range of photon energies where the peaks were found resulting from the phonon conversion. The positions of peaks observed in the spectra of positron radiation are shown to agree with predictions of the theory of phonon conversion by relativistic charged particles.

Angular distributions of photons produced by 633 and 1200 MeV electrons in a silicon single crystal, 250 {mu}m thick, have been measured at different orientation angles between the electron beam direction and the crystallographic axis <111>. It is shown that the angular distribution of low-energy radiation of electrons moving along the <111> axis is narrower than that of high-energy radiation.

The paper is devoted to the experimental study of high-energy electrons interaction with diamond crystals of different thicknesses at small incident angles with respect to crystallographic axes and planes. The effect of the so-called channeling phenomenon on the process of electron radiation in a crystal is studied. Results of the measurements of 4.5. GeV electrons radiation spectra at incident angles approximately O are given. For comparison, we have also presented the spectrum of the radiation on an amorphous target {sup 12}C of similar thickness. Results indicate that the low-energy part of spectra greatly surpass the amorphous spectrum with a pronounced peak structure, with peak widths being noticeably wider in the case of axial channeling than in the planar case. Spectra are measured by a No.I(Tl) total absorption detector. The experiment is performed on the Yerevan electron synchrotron beam with small angular divergence.

A necessary theoretical basis which would enable the measured channeling radiation spectra to be interpreted is developed in the case when photons are registered by the total-absorption Cherenkov {gamma}-spectrometer and the number of quanta emitted by a single particle is comparable or exceeds a unit. Also, the available experimental results concerning the channeling radiation of positrons in thick crystals are discussed.

The comparison is made of the intensity of relativistic particles channeling radiation with that of the radiation in magnetic multidomain structures (microundulators) and in conventional macroundulators. The radiation in microundulators is shown to be negligible as compared both with channeling radiation and accompanying bremsstrahlung. It is also shown that in the ultraviolet range of frequencies microundulators are the most efficient sources of radiation. In the X-ray region of frequencies the radiation intensities in macroundulators and during the channeling are comparable, whereas in the harder region of frequencies the channeling radiation remains unrivaled.

The problem of the radiation of a charged particle passing through the spiral undulator in dispersion medium is solved. The effect of the radiation spectrum narrowing is considered. It is shown that one may generate a fairly powerful directed quasi-monochromatic beam of hard quanta by means of relativistic bunches obtained in modern storage rings. Such beams may be applied in different fields of scientific research.

The analytic expression for the charged particle trajectory at the inclined passage through the spiral undulator is obtained. The condition of validity of the undulator magnetic field approximation is found. It is shown that the change in spectral characteristics of the charged particle radiation due to inclination will become more noticeable as the inclination parameter approaches the unit.

The behaviour of Bloch wave reflection coefficients from potential barriers and wells for the nearest above-barrier energy band as a function of quasi-momentum in the Brillouin zone is investigated for different energies of channeled electrons and positrons. The variation of above-barrier reflection coefficients for the whole energy spectrum at transition from one energy band to another for each fixed energy value of incident particles is also studied. The oscillating behaviour of reflection coefficients is shown.

The action of electron irradiation of the structural properties of silicon was studied.

On an example of planar-channeling peculiarities of transverse motion eigenstate structure of 4 MeV electrons channeled in monocrystals GaAs and GaP, it was shown that asymmetry of planar potential is most important for deep-lying bound states. But selection rules for bound-bound and free-bound radiative transitions of channeled particles are influenced by asymmetric plane potential. Some estimates were given on electron current density needed for amplification of near-infrared radiation in GaAs by stimulated transitions of channeled electrons.

Different types of optical radiation in channeling of electrons in a crystal have been considered: the Cherenkov radiation of incident and delta-electrons, transition radiation and that in spontaneous transitions between the levels of transverse energy. It has been shown that in thick crystals the Cherenkov radiation of delta-electrons is significant. In a thin crystal it is possible to observe the optical radiation associated with spontaneous transitions at angles close to 90{sup 0}. This radiation may allow us to observe the anomalous Doppler effect, which was earlier considered by Frank and Ginzburg.

The paper is concerned with the results of absolute measurements of spectral radiation intensity distribution of 1165 MeV electrons moving at small angles relative to the <110> axis in a diamond single crystal, 2000 {mu}-m thick. In the oriented crystal, the radiation intensity at the maximum of the spectral distribution (30-35 MeV) has been measured to be 11-12 times larger than the radiation intensity of electrons in an amorphous target of the same thickness. The shape of the spectrum in in qualitative agreement with the spectral distribution obtained for the diamond crystal of smaller thickness (300 {mu}m), which indicates that in this range of thicknesses one mechanism of radiation, viz. the above-barrier particle radiation, dominates.

An important design feature of advanced gas-cooled reactors is the facility to refuel routinely while on load. Part of the safety case for this requires the

demonstration that the debris resulting from a dropped stringer will remain adequately cooled. A combined experimental and theoretical approach based on simple, but fundamental, concepts was adopted to obtain an understanding of the mechanisms that control the propagation of damage through the stringer. Four major mechanisms for absorbing energy were identified: the initial sleeve failure, sleeve crumbling, pin buckling and friction. A series of basic experiments was carried out on fuel stringer components to investigate the modes of failure, to measure the energy absorbed in each process and to show how failure propagated. Irradiation has a pronounced effect on the properties of the steel and graphite which make up the fuel elements and so a programme of materials testing was also initiated. A simple theory has been developed which can be used to estimate damage in a variety of conditions. On-power refuelling at moderate powers is now a routine operation.

The derivation of anomalous Ward-Takahashi identities related to chiral symmetries in the path-integral framework is presented. Some two-dimensional models in both abelian and non-abelian cases are discussed. The quantization of such theories using Weyl fermions is also presented. (L.C.).

A quantum electrodynamical treatment of Coulomb excitation in relativistic heavy ion collisions is presented. It is shown that a subtle interplay between quantum and relativistic kinematical effects induced by the nuclear recoil due to the excitation generates a qualitatively different prediction (in certain kinematical conditions) from the corresponding prediction of conventional theories. The present formalism is applied to the clean fission problem and the results seem to solve the puzzle associated to this process for some time.

A theory of gravity wich considers the topological invariant I = R*/sub {alpha}//sup {beta}3={upsilon} R/sup {alpha}{beta}3={upsilon} as one of the basic quantities to be present in the description of the dynamics of gravitational interactions is presented. A cosmical scenario induced by this theory is sketched.

It is studied how different parametrizations of the Thirring model behave under finite chiral rotations with the zeta -function regularization for the fermion determinant. It is shown that in some cases the contribution from the chiral Jacobian may change the sign of the factor which multiplies the quadratic term in the auxiliary field leading to an exponentially divergent theory. It is also proposed how this problem could be remedied by exploiting the invariance of the theory under finite renormalizations.

Through a familiar example ({delta}function potential in one dimension) the analytic properties of Jost functions associated with fourth order equations are presented. It is shown how to construct the Jost functions and the two discontinuities matrices associated to the line of singularities. The latter divide the complex k-plane in eight regions of analiticity. One of these matrices is related to the asymptotic behaviour of scattering state. The other is not. Both being necessary to solve the inverse problem. Besides the usual poles related to bound states there are also other poles associated with total reflexion.

An analysis of some aspects of gauge transformations in the context of Dirac's theory of constrained systems is made. A generator for gauge transformations is constructed by comparing phase space trajectories with the same initial data but different choices of the arbitrary functions. An application to the Yang-Mills theory is performed. (L.C.).

The quantization of a system subject to a friction force quadratic in the velocity and position dependent is carried out in the Feynman path integral framework. The resulting Hamiltonian coincides with the one obtained by using the Weyl-ordering canonical prescription.

On the basis of experimental data on distribution of void fraction and liquid temperature in a tube in thermally non-equilibrium two-phase flow analysis of possible errors of determining void fraction by contactless methods ({gamma}-

radiation moderated neutron method) is carried out. Correct determination of true volume steam content in these cases is shown to require additional information on the profile of liquid temperature along the channel cross section. 8 refs.; 6 figs.

Accumulation of data on corrosion in liquid metals necessitates their arrangement. Formal analysis of publications will provide significant data. Investigations on corrosion in liquid metals are becoming a separate field of applied science. A survey of 10 journals gives a notion of the principal investigations in the studied field. While classifying the scientific level of the publications, they are divided into 6 sublevels, every next of which can be characterized by higher scientific and technical degree and quality of study and material presentation. The rate of growth of papers of the empirical and first theoretical levels are considered. It is predicted that by 1992-1995 the position in corrosion science will be defined by experimental and theoretical studies belonging to a higher, second theoretical level. 11 refs.; 5 figs.; 1 tab.

Consideration is being given to the technique and results of numerical simulation of three-dimensional fields of coolant velocity and temperature in fuel element clusters with partial blocking of pass openings. The calculation technique is based on numerical solution of the equations of pulse, mass and energy conservation for reference volumes, formed by fuel element cluster divided by triangular grid system. Calculational results for velocity, temperature and pressure fields are compared with published experimental data. A conclusion is made concerning applicability and satisfactory accuracy of the applied method for calculation of complex three-dimensional flows with strong disturbances. 17 refs.; 14 figs.

Results of experimental and numerical investigation into liquid phase distribution in dispersive-annular flow at 6.86 MPa pressure, 500-1500 kg/m/sup 2/ x s flow rate and 0.4, 0.5 MW/m/sup 2/ specific heat flux are presented. It is ascertained that as the flow dispersive - annular regime is being developed, droplet concentration maximum is formed in the near wall zone of a channel. Its position and value depend on the regime parameters. Effect of diffusion, convection, mass sources on the distribution curve character is numerically studied. 10 refs.; 7 figs.

Approximate formula enabling to evaluate hydraulic nonuniformity at reactor core inlet is given. The mentioned nonuniformity depends on 13 structural parameters of reactor hydraulic pipeline - from branch pipes up to the header. Dispersion technique for evaluation of the effect of structural parameter deviation on the spread of resulting nonuniformity is applied to the dependence. Coefficients of the effect have been obtained. Calculation has been conducted for the example, the minimal flow rate in reactor channel has been evaluated as 0.65+-0.14. 11 refs.; 1 fig.

Results of mathematical simulation of major strains, occuring under the swelling of hollow cylindrical column of a fuel rod, placed into hard coating are presented. Strain-stress state of fissile material, its free swelling being described in terms of spheric gas pore model, is considered on the basis of the finite strain theory. A system of ordinary differential equations is derived, describing considerable form change of the internal hollow of cylinder out of fissile material under its constrained swelling in hard coating. Results of numeric integration and analytical solution of the derived differential equations for a wide spectrum of the model parameter values are presented. 6 refs.; 4 figs.

A new method for solving the problem on multi-photon ionization with regard to Coulomb interaction in the final state is proposed. Schroedinger equation solution in the continuous spectrum in the electromagnetic wave field is found for one-dimensional case in semi-classical approximation taking into account Coulomb interaction. Probability of multiphoton ionization is calculated. It is shown, that in contrast to the case with a short-operating potential, ionization

probability near the threshold has a final value and contains a factor, exponentially depending on the field frequency. 10 refs.

Special neutron guide aimed at very slow neutron extraction and also the source of ultracold neutrons with distilled water converter are described. Efficiency of ultracold neutron extraction is presented, velocity spectrum of the extracted neutrons is determined. The guide consists of two horizontally bent 12Kh18N10T stainless steel tubes 159x4 mm in diameter. The tubes are placed one above the other and are mutually joined by a short inclined section, approximately 30 cm far from the end of lower tube, that enters in the reactor core berillium reflector. The upper tube is horizontal, the lower is slightly inclined to the horizon. Vertical distance between tubes in attaching point is {similar_to}25 cm, and at the outlet from biological shielding is {similar_to}50 cm. Prospects for the guide application are bound up with changes to low-temperature converters, in particular, to parahydrogen one. Gaseous helium cooled cryogenic loop aimed at cooling such converter is designed, produced and tested. The above-mentioned specialized guide was erected during recostruction of IRT-M reactor. 6 refs.; 6 figs.

Possibility of determining electron thermal conductivity by thermal wave propagation at the beginning of ecr-heating in a tokamak is investigated. It is shown, that under heating with sufficiently sharp edges of absorbed SHF-power profile electron temperature increment relation in the points near the heating zone edge appears to be just a self-model function of a single argument. This allows one to derive an analytical formula for determining the local thermal diffusivity a series of numerical calculations has confirmed the correctness of the analytical formula and allowed one to determine the optimal region of measurements. 3 refs.; 6 figs.; 1 tab.

Method for determining the energy confinement time in the plasma filament electron component in the T-13 tokamak is considered. Determination techniques are described and experimental results, concerning the measurement of plasma filament geometric parameters, plasma density, electron temperature by X radiation using filter technique and by plasma conductivity, energy losses due to radiation and diffusion, energy life-time are presented. The role of accelerated electrons in plasma energy balance and current drift is estimated. 23 refs.; 24 figs.

The main requirements to magnetic system of axially-symmetric magnetic trap, intended for studying flute instability of ion-hot plasma, filling the magnetic trap with the help of additional stabilizing cells, connected to the both of its cones, in the form of cusps, filled by electron-hot plasma, are formulated. The search for an optimal variant of the trap magnetic system was conducted empirically. A large number of variants was considered, differing from each other in the shape, dimensions and relative position of magnet coils. It is shown, that in order to allow passage of 0.3-0.5 W magnetic flux from loading cell into cusp, the cusp magnet internal diameter should be sufficiently large. Application of copper windings cooled by liquid nitrogen, appears to be the optimal variant for producing maximal magnetic fields. 11 refs.; 7 figs.

A meter-and-a-half isochronous cyclotron is reconstructed for the purpose of producing radioactive isotopes in it with a possibility of a fast transition to acceleration of semiheavy ions, used for nuclear-physical investigations. Ion source brightness increase, substantial reduction of the accelerated beam emittance by radial-phase collimation reduction of beam losses during extraction and transport, RF system reconstruction, start-up of remote control target device have provided for a reliable target irradiation by 600 W power beam without target thermal destruction. 10 refs.; 9 figs.

Theoretical prerequisites and methods for laser fluorescent spectroscopy (LFS) to measure heavy impurity concentration in a tokamak with TO-2 diverter are described with the purpose of organizing plasma diagnostics in the T-15 tokamak. Results of measuring iron atom absolute concentrations during discharge in the TO-2 tokamak near-the well area by LFS method are presented. Preliminary

experiments on detecting channel absolute calibration by the fluorescent signal of a tube with a hollow cathode, pumped by probing laser radiation are conducted. 15 refs.; 6 figs.

Review of modern state of neoclassical theory, concerning plasma rotation in a tokamak at minor rates (as compared to the thermal one) is given. The prevailing style of the work is the hydrodynamic one, which allows one to trace the conservation laws and the relationship between toroidal pulse relaxation and plasma diffusion processes. Kinetic coefficients are calculated using simple gaseous-kinetic estimations and their values, obtained from kinetic equation solution, are given as references. Results of neoclassical theory for plasma rotation at high rates are briefly presented. The role of anomalous processes is also considered. 20 refs.

Calculational model for determining ionization equilibrium, energy level population density and radiative energy losses from a high-temperature homogeneous stationary plasma is descirbed. Calculational results for optically transparent plasma and under final characteristic dimensions of region, occupied by plasma, are presented. The model allows one to perform calculations for plasma, containing ions with the electron number, which does not exceed 10-12. 23 refs.; 7 figs.

Method for registering short ({similar_to}150 ns), low power ({similar_to}10/sup -7/ W), 10.6 {mu}m wave length pulses of radiation is investigated. Duration and power calibrated radiation pulses were formed by electrooptical modulator from the continuous CO/sub 2/-laser radiation. Detecting system included cooled high-ohmic fast responce photodetector Si:B and a charge-sensitive amplifier. It is shown, that the minimum detectable radiation energy makes up {similar_to}3.10/sup -15/ J. Comparison of pukse detection efficiency to the detection efficiency of pulse scattering on ruby laser radiation plasma shows, that the detection method described may be applied in diagnostics of multipulse Thomson scattering in CO/sub 2/-laser for measuring the plasma electron temperature in tokamaks. 8 refs.; 12 figs.

The full text of the third agreement to extend the regional co-operative agreement for research, development and training related to nuclear science and technology of 1972 (INFCIRC/167) (extended first in 1977 and then in 1982) for a further period of five years with effect from 12 June 1987, is reproduced.

The dynamical breakdown of chiral symmetry in a finite Abelian gauge theory using a variational approach for the effective potential for composite operators is discussed. It is shown that, at least in a variational approach, the fermion either remains massless or gets a dynamical mass for every non-zero coupling constant.

Exterior variational calculus is introduced through examples in field theory. It provides a very simple technique to decide on the existence of Lagrangians for given equations of motions and, in the case, to find them. Only local aspects are discussed but the analogy to exterior calculus on finite dimensional manifolds is complete, strongly suggesting its suitability to the study of topological aspects.

From the hypothesis that our Galaxy, in an early stage of its evolution, was a quasar, it is assumed that images of this stage can still be observed in the sky. Thus, a quasar catalog is investigated for the ones that can possibly interpreted as images of our Galaxy in that stage, expecting to fit an Einstein-de Sitter cosmological model with 3-torus topology for the spatial sections.

A method to gate the wire gas discharge photodetector with electrical and fibre-optical readout has been investigated. No restrictions due to positive space-charge effects have been revealed in the flux range up to 5x10/sup 5/ p.photoelectron./mmxs per anode wire. In the fibre-optical readout the hodoscope photomultipliers are used for the light detection at the fibre exits. In this case a coordinate resolution along the anode wire makes up 3mm. 11 refs.; 5 figs.

Space and energy characteristics of hadron showers were studied for the first time with the help of the total hadron absorption detector made from the lead glass. The calorimeter having longitudinal and transverse hodoscopic structure with 10 cm step is exposed to particle beam e/sup +/, {mu}/sup +/, {pi}/sup +/, K/sup +/, p at 5, 10 and 13 GeV/c. The data on the energy and coordinate resolution, hadron and electromagnetic shower separation have been obtained. 6 refs.; 7 figs.; 4 tabs.

Multiplicity distributions of all charged and negatively charged particles for non-diffraction events in {pi}/sup +/p and pp-collisions at 250 GeV/c ({radical} s=22 GeV) are presented for various rapidity intervals. The data are well described by the negative binomial distribution. The parameters of these distributions for the {pi}/sup +/p and pp and are different for full phase space, but similar for the central region. In the central region, the relation k/sub ch/ {similar_to}1/2k/sub -/ holds for all charged and negative multiplicities. This favours to the interpretation in terms of cascade models rather than stimulated emission models. 12 refs.; 2 figs.

The paper presents the total and differential cross sections of the {nu}n -> {mu}/sup -/p and {nu}-barp -> {mu}/sup +/n quasi-elastic reactions at neutrino energies of 3-20 GeV. The data are obtained from the exposure of the SCAT chamber filled with freon at the Serpukhov accelerator neutrino channel. The results are compared with V-A theory. Within dipole approximation a value has been obtained for the axial mass M/sub A/=(0.96 +- 0.04 +- 0.14) GeV and M/sub A/=(0.72 +- 0.11 +- 0.020) GeV for {nu} and {nu}-bar data respectively. 23 refs.; 2 figs.

The method of quantization in the neighbourhood of the classical solution based on the direct perturbative solution of the Cauchy problem for Heisenberg field equations is considered after the example of non-linear scalar field models in two-dimensional space-time. Like in classical Bogolubov-Krylov method zero modes are shown to appear as a result of perturbative expansion of Bogolubov's operator-values argument of classical component. With the help of LSZ-procedure a complete investigation of the soliton sector asymptotic states is carried out in the lowest perturbative orders. 18 refs.

The representations in terms of ratios of entire (quasi) periodic matrix functions have been obtained for trigonometric R-matrices related to the classical Lie algebras. The unitarity of R-matrices for these representations can be easily verified. 12 refs.; 2 tabs.

The results of calculating geometrical characteristics of seven-dimensional quotient spaces are represented. These quantities are necessary for the construction of compactifying solutions of the eleven-dimensional supergravity. 12 refs.; 7 tabs.

A complete set of differential cross sections has been obtained in Born approximation for pair production of exotic particles with various spins J=0, 1/2, 1 and quantum numbers (colored and colorless) both in qq-bar and gg-collisions. The connection of the unitarity of vector boson processes with gauge invariance, factorization properties of non-Abelian gauge amplitudes and the presence of kinematic zeros is used. Besides, the problem of admissibility of massless limit for these processes is being discussed. The yield of exotic particle pairs at pp(p-barp) colliding beams in TeV energy range have been calculated and limits for the accessible mass range have been found. 13 refs.; 12 figs.

A relationship between self-duality equations in four-dimensional space and the main chiral field problem in n-dimensional space has been established. The general solution of the self-duality equations which depends on the necessary number of the functions of three independent arguments coincides with the general solution of the main chiral field problem when the space dimension goes to infinity. 8 refs.

Six new infinite series of trigonometric solutions to triangule equations (quantum R-matrices) associated with the nonexceptional simple Lie algebras: sl(N), sp(N), o(N) have been obtained. R-matrices are given in two equivalent representations: in an additive one (as a sum of poles with matrix coefficients) and in a multiplicative one (as a ratio of entire matrix functions). These R-matrices provide an exact integrability of anisotropic generalizations of sl(N), sp(N), o(N) invariant one-dimensional lattice magnetics and two-dimensional periodic Toda lattices associated with the above algebras. 43 refs.; 3 tabs.

A two-dimensional Ising model with staggered three spin interactions in one direction and two spin interactions in the other one is presented and studied. The phase diagram of the model and its critical behaviour is explored by conventional finite size scaling and by exploiting relations between mass gap amplitudes and critical exponents predicted by conformal invariance. The model is found to exhibit a line of continuosly varying critical exponents which bifurcates into two Ising critical lines. This similarity of the model with the Ashkin-Teller model leads to a conjecture for the exact critical indices along the non-universal critical curve. Earlier contradictions about the universality class of the uniform (Isotropic) case of the model are clarified.

Critical properties of a family of self-dual two dimensional Z(N) models whose bulk free energy is exacly known at the self-dual point are studied. The analysis is performed by studing the finite size behaviour of the corresponding one dimensional quantum Hamiltonians which also possess an exact solution at their self-dual point. By exploring finite size scaling ideas and the conformal invariance of the critical infinite system the critical temperature and critical exponents as well as the central charge associated with the underlying conformal algebra are calculated for N up to 8. The results strongly suggest that the recently constructed Z(N) quantum field theory of Zamolodchikov and Fateev (1985) is the underlying field theory associated with these statistical mechanical systems. It is also tested, for the Z(5) case, the conjecture that these models correspond to the bifurcation points, in the phase diagram of the general Z(N) spin model, where a massless phase originates.

An experimental study on the influence of the vertical magnetic field of the TBR tokamak on the stability and equilibrium of plasma column, was done. Magnetic pick-up coils were built to measure plasma current and position, together with active networks, necessary fo the electronic processing of signals. Some measurements were on the space configuration of the vertical field, and on the influence due to the toroidal vessel. From the data obtained it was possible to discuss the influence of the currents induced on the vessel surface, on plasma equilibrium. Theoretical and experimental results of the vertica field, as a function of plasma current were compared, and allowed an evaluation of the plasma kinetic pressure and temperature.

The Australian Consumers' Association's Inquiry into Food Irradiation was undertaken at the request of the Commonwealth Minister of Health, Dr N Blewett. The terms of reference of the Inquiry covered the implications of food irradiation in terms of consumer health, the environment, and the cost to the consumer.

The results of an analysis of neutrino and anti-neutrino interactions on deuterium are presented. Deuterium has been chosen as target material because it provides a means to study interactions on protons and neutrons separately within the same experimental setup. The data were taken with the Big European Bubble Chamber (BEBC) which was extended with an Internal Picket Fence (IPF) and an External Muon Identifier (EMI), and the data processing was performed by the WA25 collaboration. The various neutral current/charged current ratios are presented. Using these ratios, the individual chiral coupling constants are determined with high accuracy. The results are found to agree very well with the predictions of the standard SU(2)/sub L/ X U(1)/sub y/ model. 75 refs.; 68 figs.; 12 tabs.

In this thesis several characteristic properties are described of {pi}/sup +/p, K/sup +/p and pp collisions at an incident beam momentum of 250 GeV/c, and compared to characteristics of other energy. The experiment has been performed in the European Hybrid Spectrometer (EHS) exposed to a tagged meson enriched beam. The rapid cycling bubble-chamber and the other detector elements which comprise EHS are described in Ch. 2. Events used for the analysis have been scanned, measured and merged with the electronic counter information. After the merge steps the data have been processed through a chain of reconstruction programs (Ch. 3). In Ch. 4 the multiplicity distributions and topological cross sections are presented. An introduction to the models (Monte Carlo programs) is given in Ch. 5. In Ch. 6 the characteristics of charged particle production in {pi}/sup +/p, K/sup +/p and pp collisions at 250 GeV/c are presented. In Ch. 7 the forward {pi}/sup 0/ production is presented, a study of rho and omega resonance production in the forward hemisphere in Ch. 8. In Ch. 6, 7 and 8, the data are compared to predictions from the Monte Carlo programs described in Ch. 5. 117 refs.; 70 figs.; 23 tabs.

A multichannel unit of the analog-to-digital converter (ADC) designed for analog data acquisition and processing in physical experiments is described. The unit has 32 analog inputs with the aperture delay being not more than 100 ns. Bit capacity is 10 bits, time of transformation - 40 {mu}s/channel. 2 refs.; 1 fig.

Cross sections of the following exclusive reactions: {pi}/sup -/p -> {Lambda}/sup 0/, {Sigma}/sup 0/K/sup 0/, {Lambda}/sup 0/{pi}/sup 0/, {Lambda}/sup +/{pi}/sup -/, {Sigma}/sup 0/K/sup +/{pi}/sup -/, {Lambda}2[/sup -/K*/sup +/(K*/sup +/ -> K/sup 0/{pi}/sup +/), {Lambda}/sup 0/{pi}/sup +/{pi}/sup -/, {Lambda}/sup +/{pi}/sup -/{pi}/sup 0/, {Sigma}/sup 0/K/sup 0/{pi}/sup +/{pi}/sup -/, pK/sup 0/K/sup -/, pK/sup 0/K/sup -/{pi}/sup 0/, nK/sup +/{pi}/sup 0/{pi}/sup -/, nK/sup -/K/sup 0/{pi}/sup +/ and of the following inclusive reactions: {pi}/sup -/p -> {Lambda}/sup 0/ + Z/sup 0/, {Lambda}/sup +/{pi} /sup -/ + Z/sup 0/, 2K/sup 0/ + X, 2K/sup 0/ + Z/sup 0/, 2K/sub S//sup 0/ + Z/sup 0/, 2K/sub S//sup 0/ + X, {Lambda}/sup 0/{pi}/sup +/{pi}/sup -/ + Z/sup 0/, pK/sup 0/K/sup -/ + Z/sup 0/, K*/sup +/ + X, K*/sup -/ + X (where Z/sup 0/ are undetectable neutral particles) are obtain ed. The cross sections obtained are compared with the ones k nown in literature. 6 refs.; 21 figs.

The Coulomb field nonlinearity of a nonrelativistic beam leads to betatron oscillation frequency spread stabilizing free coherent oscillations related to a collective electrostatic field. The self-stabilizing effect is studied for ribbon beams using the method of linearization of the system of Vlasov equations, which numerical solution in the single-mode approximation has permitted to study the dependence of coherent oscillation eigenfrequencies on the mode number n and parameter s characterizing the form of the particle distribution function in phase space. It is shown that Coulomb dispersion for s actual values leads to self-stabilization of all modes with n{ge}. 7 refs.; 1 fig.

Explicit examples of supersymmetric systems involving finite numbers of degrees of freedom where quantum supersymmetry algebra cannot be preserved on the classical level, are constructed. Resolving the ordering ambiguities in different ways leads either to a modified algebra or to a reduced algebra, or totally destroys supersymmetry. 7 refs.

Factorization of the measure in bosonic string theory in two loops is considered. Contribution of tachyonic and massless excitations are computed. It is shown, that the contribution of massless excitations may be interpreted as a sum of squared fermionic propagators with different boundary conditions. 6 refs.; 3 figs.

The rate of a metastable vacuum decay at finite temperature in a (1+1)-dimensional scalar field theory is calculated. All the n-particle terms in the decay rate are taken into account. The results can be applied to calculate the dislocation velocity in Peierls potential relief. 7 refs.; 1 fig.

Explicit formulae are obtained for two- and three-loop vacuum amplitudes in the theory of closed oriented bosonic strings at {alpha}=26 in terms of the theta-constants, with the module space being parametrized by period matrices. 6 refs.

Hypothesis, concerning the structure of formulae for vacuum diagrams in the first-quantized superstring theory is proposed. The analytical measure in the integration over moduli space is proportional to the sum over spin structures on Riemann surfaces and vanishes because of the Riemann identities for {Theta}constants. 4 figs.

Explicitly Einstein-Kaehler metrics on some holomorphic vector bundles over Hodge manifolds are determined. 2 refs.

Metastable vacuum decay in the case of large (almost critical) energy differences is considered. It is shown that at such differences the parametrical dependence of the decay rate can be found analitically and numerical coefficients can be computed for arbitrary number of space-time dimensions. The calculations are performed in a physically interesting two-dimensional case, when the problem of metastable vacuum decay is equivalent to the one of dislocation movement in presence of external tension. 10 refs.; 2 figs.

Information on the accelerator operation in quarter 3, 1986 is presented. The elements of the magnetic optics in a transport system of extracted beams are aligned in two directions (MB-1 and MB-2). The equipment of the transport channel in building 205 with wire ionization chambers for measuring beam parameters is being continued. To improve qualitative characteristics of the beam ejected in the MB-2 direction, some work has been done on the formation and measurement of the parameters of the end magnetic field using a model of the main magnet of the accelerator. A protective screen of the ionization chamber placed inside the vacuum chamber of the accelerator is described. Data on the behaviour of a ''group'' of bench marks are given. Improvements in the systems of the polarized deuteron source ''Polaris'' are descibed. 2 refs.; 3 figs.; 2 tabs.

The possibility of concentrating Pt, Ir, Au, Ag, Re and some other elements from samples of chromites, sulfide ores, laterites, shales, titanium magnetites, and ultrabasic rocks was studied. A new simple procedure is based on sublimation of elements to be determined in air stream at 1200 deg C in the presence of some powdered reagents (e.g., TiO/sub 2/, Nb/sub 2/O/sub 5/, Nb) to enhance the yield, and on the use of chemical filters (CaO, MgO, TiO/sub 2/, Al/sub 2/O/sub 3/, Nb/sub 2/O/sub 5/) absorbing the interfering volatile elements from the gas phase. Methods of neutron activation and X-ray fluorescence isotopic excitation were used to analyze the obtained concentrates. 4 refs.; 5 figs; 3 tabs.

In the studies of nuclear reactions of heavy ions with heavy nuclei it is often necessary to determine the yields of TPE. Trioctylphosphine oxide (TOPO) has a high selectivity towards trivalent TPE and rare earths. The possibility to use target of catcher metals as salting-out agents in the extraction of TPE with TOPO from solutions containing DTPA and lactic acid was studied. The influence of the concentration of Pb, Bi, Cu, Ni, nitric acid and TOPO on the distribution coefficients was determined. The advantage of application of the method for the extraction chromatographic separation of TPE and rare earths from other elements produced in the interaction of ions with heavy elements are shown. 6 refs.; 3 figs.; 5 tabs.

A new gas-discharge particle detector, whose anode is a set of balls 2mm in diameter is investigated. The chamber is blowing down by the argon-methane-methylal gas mixture with the ratio 3:1:1. The detector operates in the self-quenching streamer mode, has high efficiency and a wide counting characteristic plateau. The maximum counting rate of particles at one ball is {similar_to}2.5x10/sup 4/ s/sup -1/. The ball-tipped anodes allow making reliable complex-shaped detectors. Two-coordinate detection of multiparticle events can be naturally organized in detectors like that. 9 refs.; 4 figs.

Results of determination of depth profiles of element content by PIXE-analysis method is presented. 1.0-3.5 MeV /sup 1/H/sup +/ and /sup 4/He/sup +/ ion beams of the JINR electrostatic accelerator have been used. Experiments were carried out for metals and Fe/sub 50/Ni/sub 30/B/sub 20/ alloy. 17 refs.; 6 figs.; 1 tab.

Multi-vortices of the 2D Abelian Higgs model on a finite lattice by relaxation of Monte-Carlo equilibrium configurations are generated and identified. The lattice vortices have action and a uniquely defined topological charge corresponding to the continuum ones. They exhibit the expected exponential decay behaviour and satisfy approximately the classical equations of motion. Vortex-antivortex superpositions are seen as well, supporting the dilute gas picture. Single vortices finally relax into ''dislocations'' and dissapear. A background charge construction turns out nearly insensitive with respect to dislocations. 22 refs.; 6 figs.

The authors give a detailed description of the method to construct finite N=1 SUSY gauge field theories in the framework of N=1 superfields within dimensional regularization. The finiteness of all Green functions is based on supersymmetry and gauge invariance and is achieved by a proper choice of matter content of the theory and Yukawa couplings in the form Y/sub i/=f/sub i/({epsilon}g, where g is the gauge coupling, and the function f/sub i/({epsilon} is regular at {epsilon}0 and is calculated in perturbation theory. Necessary and sufficient conditions for finiteness are determined already in the one-loop approximation. The correspondence with an earlier proposed approach to construct finite theories based on aigenvalue solutions of renormalization-group equations is established. 20 refs.

The effect of the retarded action of an unexcited atom A on an excited atom D is revealed by means of QED calculation. The electromagnetic field emitted by A and later absorbed by D cannot consist of photons because quanta of the field must have a negative energy. It is argued that there exist also negative-energy quanta of other fields, e.g., the fermionic ones. The appropriate experiment and consequences of the existence of these quanta are discussed. 11 refs.

The influence of the magnetic field on the selfquenching streamer discharge characteristics is investigated. In the field about 10 kGs streamer charge is decreased several per cent (change of charge is due to amplitude decreasing of signal). In the transition region from limited-proportional to streamer mode magnetic field results in increasing of probability of avalanche developing into a streamer. 3 refs.; 8 figs.

The Jaynes-Cummings model describing interaction of a two-level system with a radiation field is generalized to the case of interaction, nonlinear in bosonic variables. Exact wave functions and energy levels are found for the corresponding Hamiltonians. 4 refs.

Ionization losses (IL) of shower electrons and positrons in electromagnetic cascades produced by gamma quanta with the E/sub {gamma}/=200-3500 MeV energy in liquid xenon has been measured. The distribution of average IL along a cascade axis is described by the Weibull function. Approximation of the parameters of this function is obtained. Experimental material consists of the pictures of 180 liter xenon bubble chamber irradiated by the {pi}/sup -/-mesons with the 3.5 GeV/c momentum. 16 refs.; 6 figs.; 6 tabs.

The measurements of ionization losses (IL) of electron and positron energy in electromagnetic showers initiated by gamma quanta with the E/sub g/amma=200-3500 MeV energy in liquid xenon has been performed. Simple formulae approximating experimental data concerning average IL in direction perpendicular to the shower axis are obtained. As a source of experimental material the pictures of the 180 liter xenon buble chamber exposed in a beam of {pi}/sup -/ mesons with the 3.5 GeV/c momentum are used. 9 refs.; 8 figs.; 1 tab.

Using pictures of the 180-liter xenon bubble chamber irradiated by the mesons at 3.5 GeV/c ionization energy losses (IL) of electrons and positrons in

electromagnetic showers produced by gamma quanta with the E/sub {gamma}/=200-3500 MeV energy has been measured. Estimations of quantities describing fluctuations of shower dimensions such as variation coefficient of a part of IL along ad perpendicular to the shower axis, spread mean square, and variations of average longitudinal and transversal shower dimensions are obtained. 7 refs.; 5 figs.; 1 tab.

The indication on the anomalous production of {mu}/sup +/{mu}/sup -/ pairs beyond the target which could not be explained by the known background processes is obtained as a result of the analysis of the data registered on the BIS spectrometer in the experiment with neutral kaons. The invariant masses of these pairs are limited by the M({mu}{mu}) <or approx. 0.38 GeV/c/sup 2/. 15 refs.; 5 figs.; 1 tab.

Explicit expressions are found for a multi-soliton solution of the system of equations describing the interaction of waves on the x, y plane. The proof of all necessary statements follows from the theory of matrices and is not based on the inverse scattering method. The obtained results are closely related to some problems of the mathematical physics. 5 refs.

The structure is studied of a new solution of Chew-Low-type equations earlier obtained as series in powers of z=e/sup ln{lambda}/ convergent in a vicinity of the coordinate origin in the plane z. It is shown that these series are transcendental meromorphic functions of z with an infinite number of simple poles at points z=z/sub i/{lambda}sup k/ where z/sub i/ are roots of a certain equation. The procedure of determining roots and residues at poles is presented. 7 refs.; 2 figs.

COLLI-program complex for computer simulation of soft hadronic, hadrom-nucleus, nucleus-nucleus collisions is applied for calculation of different characteristics of the nucleus-nucleus interaction products at high energies. The quark-gluon string model is chosen as a physical model. In the inelastic nucleus-nucleus interactions the strings with quarks at their ends were first created, which decayed later into hadron chains. The Monte Carlo method is used for generating the exclusive events being the result of nucleus-nucleus collisions. In particular, the collisions of the oxygen nuclei with a series of target-nuclei within the 50-500 GeV/n energy range are considered. 15 refs.; 13 figs.

COLLI-program complex for computer simulation of soft hadronic, hadron-nucleus, nucleus-nucleus collisions is used to investigate the fast charged particle yield from the proton-nucleus interactions at high energies. Different models of cascade type are used as physical models of proton-nucleus interactions. The Monte Carlo method is applied for generation of the collision result events. 18 refs.; 9 figs.

The COLLI-program complex for computer simulation of soft hadronic, hadron-nucleus and nucleus-nucleus collisions is applied for calculation of different characteristics of products from the proton interaction at UNK energies. Instead of the physical model of the proton interaction the quark-gluon string model has been used. Due to the proton collision the strings with quarks at their ends are first produced, then they decay into hadron chains. The exclusive events - results of the proton collision are generated on th basis of the Monte Carlo method. 17 refs.; 8 figs.

The COLLI-program complex for computer simulation of the soft hadronic, hadron-nucleus and nucleus-nucleus collisions at high energies is briefly described. Instead of the physical model of the hadron inelastic interaction the quark-gluon string model has been chosen. Different models of the cascade type may be used for consideration of the hadron-nucleus and nucleus-nucleus interaction. The Monte Carlo method is applied to generation of the event as collision result. The programs have been written in FORTRAN standard. The PATCHY system package is used for storage, updating and employment. 19 refs.

The result on heavy water investigation at 23; 130; 200 deg C temperatures using slow neutron inelastic scattering method are presented. The experimental equipment for neutron investigations of molecular dynamics of liquids in a wide range of temperature and pressure variation is described. Experimental double-differential cross sections of the slow neutron scattering by heavy water are transformed into the scattering law at Planck constant{omega}=const and Q=const. The anomalous behaviour of the scattering law curves are noticed. 28 refs.; 7 figs.

The spectral problem is formulated for a quantum-mechanical system of three Coulomb particles with a total angular momentum J. The problem included a system of (J+1) differential equations in a three-dimensional space and boundary conditions corresponding to the constraint on the wave function being finite throughout the whole space. For the problem, a variational functional of the Rayleigh-Ritz type is constructed in hyperspherical coordinates. This formulation is aimed at creating effective variation-difference schemes for calculating physical characteristics of three-particle systems. 11 refs.; 2 figs.

The Friedrichs model, i.e. a pair of operators H/sub 0/ and H=H/sub 0/+V, where H/sub 0/ and H are the free and perturbated Schroedinger operators respectively have been investigated. The perturbation V is an integral operator with nondiagonal singularity. A convenient intertwining operator T is constructed and the existence and completeness of the generalized wave operators are proved. 10 refs.

Using the method of matrix linearization of polynomially nonlinear equation system a system of linear nonhomogeneous matrix equations is compared. Solutions of linear equations-accompanying matrices - are general solutions of original nonlinear problem in matrix representation. The algorithm of constructing the structure of basic vector and matrix-coefficients of linear system is given. A method for separating unknowns in polynomially nonlinear problem is expounded. The algorithm of construction of basic vector and unitary matrix, the columns of which consist of eigenvectors, in the method of linearization of quadratic equations by means of the Clifford algebra is proposed. The concepts of matrix differential and matrix derivative for multidimensional function are introduced. 7 refs.

Direct measurements of rates of carrier-free lanthanum-140 electromigration (T/sub 1/2/=40.3 h) were used to obtain dependences of mobility (u-bar) on concentration of two-charge ions of oxalic and tartaric acids in aqueous solution with 0.01 ionic strength and at 298.1 K. Using experimental data, concentration stability constants and individual mobilities u/sub i//sup 0/ oxalate and tatrate La(3) complexes were calculated: [La(C/sub 2/O/sub 4/)]/sup +/, [LgK/sub 1/=5.63(9), U/sup 0/=+1.95(15)x10/sup -4/ cm/sup 2/ s/sup -1/ v/sup -1/; [La(C/sub 2/O/sub 4/)/sub 2/]/sup -/, LgK/sub 2/=4.05(19), u/sup 0/=-1.76(20)x10/sup -4/ cm/sup 2/ s/sup -1/ v/sup -2/; [La(C/sub 4/H/sub 4/O/sub 6/)]/sup +/, LgK/sub 1/=4.40(5), u/sup 0/=+1.99(18)x10/sup -4/ cm/sup 2/ s/sup -1/ v/sup -1/. Obtained results were correlated with publication data. The limiting mobility of La/sup 3+/ was calculated: u/sub La(sup 3+)//sup (M=0)/=+6.9(1)x10/sup -4/ cm/sup 2/ s/sup -1/ v/sup -1/. 30 refs.; 3 figs.; 3 tabs.

It si shwon that existing in a real magnetic system of a linear induction accelerator (LIA) random spread of the axes of the focusing magnetic field separate coils relatively to the accelerator axis reduces to the centre of the beam mass precession, leads to the increasing of generalized momentum and to appearance of particle coherent angle at the accelerator exit. The correlation functions connected with the random spread of the coils center coordinates relatively to the LIA axis are determined, and the quantity of the coherent angle and amplitude of the precession at the accelerator exit are evaluated. 5 refs.; 3 figs.

Simple and effective criterion for separation by electric charge of relativistic particles registered by a set of scintillation counters is proposed. This criterion of aceraged amplitude is weakly sensitive to change in counter mode of operation and gives a possibility to separate particles on the significance level of about 10/sup -4/-10/sup -5/. The effect of the criterion is illustrated using inclusive spectra of relativistic fragments from the reaction of {alpha}-particles with light atomic nuclei obtained by means of the MASPIK magnetic spectrometer. 10 refs.; 2 figs.; 2 tabs.

The {omega}/sup 2/ statistics is used to separate by electric charges the relativistic nuclear fragments detected by a set of 5 scintllation counters of the MASPIC magnetic spectrometer. Estimations of significance level for the hypothesis Z=1 and probabilities to take a particle with Z=2 for a one having the charge Z=1 have been performed. Numerical results are obtained using experimental data concerning reactions of {alpha}-particles with light nuclei at 4.5 GeV/c/N. 5 refs.; 3 figs.; 1 tab.

The automatic system for servicing experimental investigations with polarized neutrons and nuclei is described. It consists of the SM-3 mini-computer and CAMAC equipment. The system permits to store a few time-of-flight spectra simultaneously, and to control the experimental set-up, as well as to control experimental conditions and to analyse the accumulated spectra. 16 refs.; 5 figs.

An elementary introduction to the quantum inverse scattering method (the R-matrix method) is given in. Essential algebraic structures of the method are explained in detail. 32 refs.

The paper present data on radiosensitivity of two stems R-20 and R-15 of Ruta graveolens (differing in their biosynthetic activity) manifested in the change of growth rate, rutacridon concentration and ''yield'' of rutacridon alcaloid. The results are discussed of tissue irradiated performed at IBR-2 biophysical complex (Regata installation) under various dose powers in the pulse (from 10 Gr/s to 1x10/sup 4/ Gr/s) in the dose range from 0.3 to 400 Gr. It is observed that neutron irradiation stimulates Ruta graveolens cell growth, increase the ''yield'' of rutacridon alcoloid under stimulating doses from 0.3 to 5.0 Gr in the first passage after irradiation. The stem R-15 reveals a higher radiosensitivity than the stem-producent. From the results obtained with Regata installation one may see that the rutacridon concentration increases with increasing doses. Cell growth suppression is observed in the second passage after irradiation both under small and greater doses. 11 refs.; 4 figs.

Problems related with the NIIAR experimental possibilities for performing research on reactor materials testing are considered. Neutron-physical and operational characteristics of the SM-2 and MIR reactors were essentially improved in result of reconstruction. New RBT-6 and RBT-10 pool type reactors using spent fuel assemblies of the SM-2 reactor were created. The complex of capsules enabling to realize the required temperature conditions during irradiation of reactor material samples with up to 5x1/sup 6/ W/m/sup 2/ surface heat flux density was designed. Techniques and capsules for testing high-temperature gas cooled VTGR type reactor fuel elements were created. Techniques for corrosion resistance testing of zirconium base alloys, as well as the materials for fuel cans and channel tubes of the WWER and RBMK type reactors were developed. The original irradiation devices and techniques enabling to test fuel elements at alternating power are installed in SM-2 and MIR reactors in connection with development of NPPs operating under intake load following conditions (maneuvering conditions). 8 refs.

General principles of designing, status and prospects for the automated research and management systems at the Research Institute of Atomic Reactors are presented. Urgency of complex investigations carried out in the institute assuring acquisition, processing and holding of the data to prove key concepts of design approaches to newly built commercial NPPs is stressed. Description of automated research systems in three main scientific directions: in reactor

materials technology, radiochemistry and chemical technology, nuclear reactor physics and technology, is presented. Status and prospects for the automated management system that is under the development in the Institute and comprises main functional and specialized subsystems are considered. 9 refs.; 7 figs.

Presented are the most important data which have been obtained as a result of studies on actinide oxidation-reduction reactions in water solutions, on the production and properties of metals, intermetallic compounds and alloys with noble metals, on chemistry and structure of the solid transuranium element complex compounds. The main stages on developing the transuranium element chemical technology are considered. The process scheme for transuranium element extraction out of the irradiated targets and the techniques for analytical surveying the above process are described. The examples are given of /sup 252/Cf practical application to various-purpose neutron sources. 20 refs.; 3 figs.; 2 tabs.

Some oxygen-contained impurities have been detected in both the AST-1 Atomic Power Station ditolylmethane coolant and deposits using infrared spectroscopy, polarography and potentiometry. Adsorption methods for their separation from the coolant are described. It has been shown that the ditolylmethane oxidation products contain the oxygen-group compounds (aromatic alkohols and phenols), aromatic acids, aldehydes, ketones and ethers. 24 refs.; 9 figs.; 2 tabs.

Comparison of extraction rates of a number of actinoids, lanthanoids and zirconium both in extractors with fixed surface of phase contact and in those with intensified mass transfer in emulsion regime of mixing, specifically in centrifugal extractors, is performed. In spite of different extracted components and diluents, close values of specific phase interface at the same mixing intensity for system with TBP are obtained. 35 refs.; 10 tabs.

In the regulatory framework of the GDR all measures aiming to ensure the safe use of atomic energy are defined by the term Atomic Safety and Radiation Protection, where atomic safety includes nuclear safety, physical protection and nuclear material control. In 1984, a new Atomic Energy Act went into effect followed, in 1985, by the new Ordinance on the Assurance of Atomic Safety and Radiation Protection and the pertaining Executory Provision. Section 2 of the Ordinance defines the following goals for the safe use of atomic energy: (1) the protection of life and health of man, and, from the genetic point of view, also of future generations from the harmful effects of ionizing radiation; (2) the protection of the environment from radioactive contamination, in particular by the careful handling of radioactive materials and safe disposal of radioactive wastes; (3) the protection of workers in nuclear facilities and of members of the public in their surroundings, and of material assets by strict observance and implementation of nuclear safety and radiation protection measures; (4) the protection of nuclear material and nuclear facilities from any criminal attacks and unauthorized interference; and (5) the fulfilment of the Safeguards Agreement concluded between the Government of the GDR and the IAEA by accounting for the use of nuclear material exclusively for peaceful purposes. Under Section 6 of the Atomic Energy Act, the National Board for Atomic Safety and Radiation Protection (SAAS) is the competent authority for the state control in the field of protection against the risks from the use of atomic energy, which is exercised by licensing and surveillance as described in this report. Other topics also dealt with in more detail are the in-plant organization of atomic safety and radiation protection and the powers of the regulatory body to impose enforcement measures and sanctions in the event of non-compliance with the pertinent provisions.

A celebration and a scientific colloquium dedicated the 30th anniversary of the foundation of the Central Institute for Nuclear Research (CINR) of the GDR Academy of Sciences were held on January, 23rd and 24th, '86 at Rossendorf. The speaches and lectures given by the president of the GDR Academy of Sciences and by scientists of the CINR dealt with problems of policy of science, history of the CINR, nuclear methods, microelectronics, nuclear energy research, development and production of radioisotopes and scientific instruments.

During the past decade, increasing effort has been given to monitoring coal quality in the search, production and preparation sequence. Considerable research and development has been carried out on nuclear methods for determination of ash in coal. A number of nuclear techniques are now well established for coal analysis. In particular, the spectrometric gamma-gamma technique is based on the existence of a simple correlation between the ash content and the equivalent atomic number of coal. This technique records and uses the count rates of the backscatter spectrum. These count rates describe the changes in spectral shape which are due to ash content variations. This method is presented along with a short review of the physical background. The report includes the simulation of in situ borehole probe readings using a MONTE CARLO tracking program. Simulating the transport through matter of gamma-rays by MONTE CARLO techniques essentially attempts to reproduce the actual statistical nature of the interaction processes. Random numbers are used throughout, along with known nuclear data, to select the parameters which influence a particle's history. Such an approach can deal with complex geometries through which the particles move. Biaising or weightening techniques are applied for variance reduction, so as to minimise the statistical errors. The basic features of biaising as well as the description of the program are given. A semi-theoretical approach is discussed for the determination of ash content of coal seam using the simulated spectrum.

SmS has been studied for its transition from the low pressure black phase to the high pressure intermediate valence phase; but the black phase properties seem to be very rich. The variations which pressure of the low-temperature electronic transport properties show the existence of a semi-metallic phase within the black phase domain in a pressure-temperature diagram, for a pressure above 4 kbar, which corresponds to the so-called B'phase. We study the insulating low pressure phase with a model involving acceptor like states. Using electronic paramagnetic resonance experiments we observe a square symmetry trivalent samarium ion neighbour of a sulfure defect, and magnetically coupled with the lattice. This defect exists in two nearly symmetric configurations and the resonance line broadens with temperature in an actived way. It gives rise to metastable effects yielding conductivity relaxations, analysed with stretched exponential laws, because the defect traps magnetically conduction electrons forming a bound magnetic polaron. The relaxation time at zero field is temperature actived. We develop a phenomenological model that gives the good orders of magnitude for the trapping barrier and for the critical field corresponding to the maximum of the low temperature magnetoresistance.

Some of the organized phases formed by the ternary system NaDEHP/water/benzene have been identified and characterized by means of phosphorous NMR, light scattering neutron and X-rays diffraction. A Mn/sup 2+/ ion, fixed to the phosphate head, induces on the surfactant molecules on one hand, on the solvent ones on the other hand a relaxation the measurements of which leads to the different conformers probabilities and the solvent penetration to the micelle. The treatment of the surfactant nuclei relaxation (/sup 31/P, /sup 13/C, /sup 1/H, and /sup 2/H) at various field allows the determination of the different molecular motions as well as the segmental motions of the chains and the order parameters of the C-H bonds. These ones, interpreted in terms of molecular geometry provide the orientation of the local director.

This report comes within the scope of the general studies on mutagenic and carcinogenic agents other than ionizing radiations. Through feeding, way of life and working activities, man is exposed to genotoxic risks of N-nitroso compounds (NNC). In spite of differences in the molecular modes of action, there exists some analogy between the effects of radiation exposures and those of NNC: DNA is the target in either instance. Unlike radiations, NNC are alkylating agents. The whole activation process of carcinogens arises from mechanisms leading to DNA repair.

The concentrations of Kr and Xe isotropes have been measured by a high sensitivity mass spectrometry technique in 11 samples from a core of the Saint-

Severin meteorite. On the basis of our results, we were able to show the role of the shielding depth on the production of Kr and Xe by cosmic ray bombardment. More-over, the experimental results for krypton were compared with calculated values obtained by the Reedy and Arnold model (1972) adapted to cosmic ray irradiation of small spherical objects. Our elaboration of a new systematics of nuclear reactions has lead to a good agreement between experiments and calculations within this model.

This thesis presents the study of the radiation effects (erosion and synthesis) with ions of low energy (a few KeV/u) in silicates and ices. The erosion of the H/sub 2/O ice is analysed by infrared spectroscopy versus different parameters: ion beam flux, mass and energy of the ions, and the thickness of the samples. The interpretation is that the erosion of the ice comes mainly from the dissociation, along the ion range, of the H/sub 2/O molecules. A study of the synthesis in SiO/sub 2/ and H/sub 2/O by carbon, nitrogen and hydrogen implantation leads to the characterization of the synthesized molecules and the determination of the yields. The irradiation of ices mixtures (H/sub 2/O, CO/sub 2/ and NH/sub 3/) leads to the synthesis of a great variety of molecules which are identified. The experimental results are extrapolated to different astrophysical situations in the solar cavity (Moon, satellites of giant planets, comets) and in the interstellar medium (molecular clouds).

The purpose of this study is to assess the modification of the flow pattern inside a granitic rock mass due to the thermal loading created by a radioactive waste repository. Data collected on the french site of Auriat are used for simulations with the numerical code METIS. The natural medium is represented by a vertical cross section covering several kilometers and integrating major inlets and outlets. The model describes the coupled flow and heat movement. Three possible geometries of the repository are envisaged corresponding to a more or less compact arrangement of the canisters and to different durations of preliminary storage. For the reference values of the parameters as well as for realistic variations, the heat transfer is shown to be indepedent of the flow, which in turn is feebly modified by the temperature rise. The thermal phase extends on a period of 10000 years approximately, with a maximum temperature increase of about 120 degrees. The behaviour of a source diluted in the total volume containing the repository is compared with a refined local model. The discrepancy between the two models vanishes after 100 years. An optimum discretization of the repository zone is defined by comparison to analytical solutions. Finally, the continuous medium model is compared to a double medium model describing the role of the fractures. The continuous model is shown to be satisfactorily for the range of parameters characteristic of the Auriat site.

For the year 1984 in France: radionuclides in unsealed sources, used in medical circles represent 4812 Ci (4812 x 37 GBq) of which 80% for Technetium 99 m alone. The market for these products has expanded greatly in fifteen years, by at least a factor of 6. the parcels are in the number of at least 200 000 of which 120 000 parcels are A labelled containing radiopharmaceutical preparations administered in vivo and radiochemical preparations used in vitro or in research. the users are few in number, 375 in all, of whom 127 are Departments of Nuclear Medicine who are the principal users; deliveries are very regular and are made along some large axes. transport accidents are extremely rare. the dosimetric data of workers are of a quality and equivalent of the collective dose for workers is in the order of 0.42 h.Sv; furthermore this equivalent of the collective dose has been recognisably the same for 15 years despite the increases in personnel and production; within the present framework of regulations concerning transport of the parcels, radioprotection of workers depends on the ethics of the suppliers. The drivers, who transport radioactive parcels only are regularly exposed to more than 10 mSv per year and the study of this group of workers should be a priority. The distribution of the doses received by packers in the large transit centres is not known. The equivalent of the collective public dose, due to the transport of these unsealed sources for medical use must be between 0.01 h.Sv and 0.1 h.Sv.

In the frame of an ''IEA Implementing Agreement'' between Canada, the EC, Japan, the US and Switzerland, a research and development programme on radiation damage on fusion reactor materials is performed. Annex II of the above agreement defines a series of joint (EC-US-Japan) fusion material irradiations in various MTR's. The present report describes the irradiation device, the irradiation history, the post-irradiation tensile tests, together with comments on the results of these PIE tests, of two of the above irradiations, corresponding to experiments 5B and 5C of the ''Oak Ridge Matrix''. The alloys included were the following: - European Reference AISI316L (''EC316'') - US reference AISI 316L (''US316'') - US P.C.A. (''US-PCA'') - Japanese P.C.A (J-PCA).

The gas shock tube used in these experiments consists of a low pressure chamber and a high pressure chamber, divided by a metal-diaphragm-to-rupture. In contrast to the shock mode of operation, where incident and reflected shocks in the low pressure chamber are studied which occur within 3.5 ms, in this work the compression mode of operation was studied, whose maxima occur (in the low pressure chamber) about 9 ms after rupture. Theoretical analysis was done with the finite element computer code EURDYN-1M, where the computation was carried out to 30 ms.

In 1980 a borehole with a diameter of 300 millimetres and a depth of 300 metres was drilled with a dry-drilling technique in the Asse II salt-mine in the Federal Republic of Germany. This borehole was used to perform a series of in-situ experiments to establish the constitutive behaviour of rock-salt, to measure the temperature-induced compression on a heated tube and to validate the computer codes for the thermo-mechanical behaviour. Three types of experiments are performed and described in this report: free isothermal convergence measurements; temperature-induced pressure measurements; free non-isothermal convergence measurements. It is shown that the thermo-mechanical behaviour of rock-salt can be described accurately with a set of constitutive equations based upon elastic behaviour and secondary creep. It is measured that the state of stress at a depth of 830 metres deviates significantly from the lithostatic pressure. This deviation is shown to be caused by the stress redistribution due to the large excavations in the mine. The maximum compression on a heated tube is measured to be about 35 MPa for a lithostatic pressure of 17 MPa and a maximum salt temperature of 175/sup O/C. In this report the results are given of a feasibility study on the dry drilling of a 600 metre deep borehole in Asse II. This study is based on the classic roller-bit configuration. Parallel, the GSF has developed a more advanced drilling technique, which will be pursued for the 600 metre hole experiment. The study under consideration must therefore be seen as a ''backing up solution'' in the improbable situation that the advanced GSF system will not fulfil its promises.

A panel has evaluated the research programme ''Nuclear measurements and reference materials'' performed by JRC-Geel, CBNM (Central Bureau for Nuclear Measurements) during the period 1980-85. Furthermore the panel has considered more general topics such as major facilities, staff and collaboration between JRC-Geel, CBNM and other organizations. Finally, the panel has discussed the future direction of the programme. The panel expressed its satisfaction with the scientific and technical quality of the work and recommended that JRC-Geel, CBNM should continue to play an important role in Europe in the fields of nuclear measurements and nuclear reference materials. The panel also recommended that the underlying research be strengthened and that the nuclear experience and expertise of JRC-Geel, CBNM be utilized for non-nuclear applications.

It is of pressing concern to understand the behaviour of radionuclides in the environment and in particular long-lived ones (e.g. Np-237 and Te-99) in argillaceous rocks. Clay formations have been chosen as likely candidates for holding low level radioactive waste repositories and in the event of leakage of radionuclides into the geosphere some knowledge of their fate is required in a far-field safety assessment study. The objectives of this present work were to examine the properties of neptunium and technetium in ground-waters associated with clay-rich materials and to ascertain the variations in sorption of these

radionuclides under different environmental conditions and to use the information in a forecast of transport through a clay layer.

As part of a research programme on the disposal of radioactive wastes in clay, Ordinary Portland Cement (OPC) has been used in the completion of boreholes on the Harwell Research Site, AERE, Oxfordshire. The purpose of this study was to examine the effect of OPC and the alkaline pore fluids generated during its setting on the various lithological types encountered in the boreholes. To facilitate this, samples of core representing the various rock types were selected and cement-rock composites were prepared from these in the laboratory to simulate the borehole cements. After a curing period of 15 months the cores and associated cement plugs were examined for any signs of reactivity or bonding. The best cement-rock bonding was shown by naturally well-cemented sandstone and limestone lithologies. Although no significant chemical reaction was seen to have occurred between OPC and rock, the OPC appears able to bind onto the rock surface because of the rigidity of the rock surface. Therefore, the best cement rock bonding and seal with OPC may be expected in the limestones of the Great Oolite Group, Inferior Oolite Group and parts of the Corallian beds. Because of the reactivity of OPC towards certain lithologies a better borehole seal in such a sedimentary sequence might be achieved using a bentonite backfill in those parts of the sequence which either react with or bond only weakly to OPC.

As part of a research programme on the disposal of radioactive wastes in clay, acoustic waveform analysis was used to evaluate the effectiveness of cement bonding for sealing three boreholes drilled at Harwell. The results from this study indicate that the bonding at both the cement/casing and, more importantly, the cement/formation interfaces would almost certainly be inadequate for the purposes of sealing a radioactive waste repository. The use of an alternative backfill material such as bentonite is advocated.

This report presents the results of a project to investigate the use of elemental profiles in Scottisch sediments resulting from the Flandrian marine transgression as a natural analogue of radionuclide migration through argillaceous material. The work was carried out within Research Area no. 5 of the CEC project MIRAGE ''Natural Geological Migration Systems''.

This booklet summarizes the six papers on neutron radiography activities at the Petten High Flux Reactor (HFR), presented at the Second World Conference on neutron radiography, held in June 1986 in Paris, France. The conference was organized by the French CEA and COFREND, and JRC Petten, HFR Division, with joint sponsorship of the national societies on Non-Destructive Testing (NDT) from the Federal Republic of Germany, United Kingdom, Japan and the United States. The Petten papers are concerned with: (i) the work of the Neutron Radiography Working Group (NRWG), an expert group operating under the auspices of the Commission of the European Communities represented by JRC Petten, HFR Division; (ii) applications of neutron radiography in research programmes performed at HFR; (iii) neutron radiography facilities at HFR; and (iv) image evaluation techniques.

Twelve parametric and non-parametric sensitivity analysis techniques are compared in the case of non-linear model responses. The test models used are taken from the long-term risk analysis for the disposal of high level radioactive waste in a geological formation. They describe the transport of radionuclides through a set of engineered and natural barriers from the repository to the biosphere and to man. The output data from these models are the dose rates affecting the maximum exposed individual of a critical group at a given point in time. All the techniques are applied to the output from the same Monte Carlo simulations, where a modified version of Latin Hypercube method is used for the sample selection. Hypothesis testing is systematically applied to quantify the degree of confidence in the results given by the various sensitivity estimators. The estimators are ranked according to their robustness and stability, on the basis of two test cases. The conclusions are that no

estimator can be considered the best from all points of view and recommend the use of more than just one estimator in sensitivity analysis.

Model tests are carried out, in order to investigate the cataclastic thermo-mechanical behaviour of rock salt around a simulated repository borehole. The measurements are performed during a transient period of heating and subsequent cooling. Acoustic crosshole measurements are carried out under conditions of compression, scale 1: 41/2. The relationship between cataclastic effects and the acoustic velocity differences is described. Macrofracturing only occurred under circumstances of cooling, when a heater was switched off. One of the model tests was used in the CEC benchmark exercise ''COSA''. Acoustic measuring tubes have been developed for the in situ research on structural changes in rock salt. The tests involved the performance of so-called hole measurements in two parallel boreholes, containing the measuring tubes. The most important observations of a test in an old room in the Asse Mine are the following. A bifurcating open fissure, about 6 to 8 mm wide, prevented the propagation of the acoustic wave; this demonstrates that such cracks and fissures are easily detectable by the applied method. The microcataclasis, particularly that near the roomside wall, causes a reduction of the acoustic velocities, the more so as the angle between the measuring direction and the roomside wall increases. During the injection of a gallery wall with epoxy resins (by GSF) acoustic crosshole measurements were carried out as well. A detailed picture was obtained of the process of the closing of the fractures. By core drilling after this test confirmation was obtained that the fractures were closed. The information that has been gathered, will be used for the interpretation of the crosshole measurements in the near future; these measurements will be carried out around a heater borehole in the HAW field, a large underground test (GSF-ECN).

The aim of this study is to provide geochemical data to be included in a model under construction to describe the migration of radionuclides through the geosphere. A large series of distribution coefficients was determined by batch and column experiments. The radionuclides were: Americium-241, Plutonium-238, 239 and 240, Neptunium-237 and Technetium-99. Geological materials were glauconite containing sand and materials from near Gorleben (Federal Republic of Germany). THe main variables of which the impact was studied were: pH, redox potential (Eh), salt concentration and contact time. Also the influence of textural composition, CEC, organic matter content and ionic composition of the associated ground waters on the sorption of the radionuclides was studied. From the data of the batch, column and microcosm studies it can be concluded that the migration of Pu, Am, Np and Tc will be strongly delayed due to adsorption of these nuclides on geological material. In anaerobic systems at low pH values Pu and Am will migrate faster than Np. For aerobic conditions, but also for anaerobic conditions at high pH, Np will migrate faster than Pu and Am. Tc may migrate in aerobic systems; it will become less mobile if reduction occurs. As far as modelling is concerned, without a rather detailed knowledge of the local redox potential and pH, a fair estimate of the migration is not possible.

The European Research program includes studies on highly watertight materials likely to sait the final cover of low-level and intermediate-level waste disposal. The experimental equipment is composed of a 26 sq. m collector placed on an inclined plane, just below the material to be tested and connected by means of a gutter with a measuring room where the infiltration waters flow rate is steadily measured. On the surface of the tumulus, a 300 sq.m inclined plane permits the measure of the running off water. The recording raingauge completes the device. Water vapour pressures are measured at different depths within the material. Total watercontents are registered along vertical profils using a special neutron logging tool. Numerous physico-chemical measures are carried out on the infiltration and running off waters: pH, Eh, temperature, dissolved oxygen, conductivity, turbidity and major anions and cations. Two materials have been tested with this device: - weathered schists; Compacted clay. The first material showed that, on average over the six months period of measurements, the overall rainfall brokedown into 11% running waters, 13% infiltration and 76% evaporation because infiltration accounts for a large part of rainfall. It

resulted in a complete saturation of the material during certain periods of the year. Humidity measurements performed at different places pointed out large heterogeneities inside the material. It is worth noting that, despite some problems due to calibration, the whole instrumentation located in the measuring room worked rather well and permitted to demonstate the bad qualities of the material. The second material was subsequently covered by a 20 cm thick layer made of a mixture of sand in order to regularize water infiltration under the soil vegetation constituted by a special grass growing.

The aim of this research is to valid the geoprospective approach elaborated previously in the framework of contracts with Commission of European Communities. The geoprospective approach is applied to a ''paleosite'' i.e. to a region the evolution of which can be reconstructed for the last 100.000 years. This work is performed on a part of Parisian Basin near the English Channel coast. It allows to simulate the combined effects of sea and river level variations, and tectonic activity. All these factors taken in a rather severe context, would not have changed significantly, the confining conditions of the geological barrier around a radioactive waste repository.

A wide theoretical study on quasi-optical microwave propagation has been carried out in the range 3 GHz - 300 GHz. A high power TEMOO Gaussian beam can be propagated for long distances with low losses if a nearly-confocal system of mirrors is used as phase corrector. The theory of beam waveguides using elliptic paraboloidal reflectors has been critically revisited and developed. All the kind of losses (diffraction, matching, truncation, divergence, ohmic, atmospheric, depolarization, misalignment) have been examinated into detail. Criteria to find the best design parameters of a quasi-optical transmission line are given once the frequency, the power and the available room are known. In general, a well designed Reflecting Beam Waveguide should permit the propagation of several MW in CW without a sensible beam shape deformation, and with total losses of about a fraction of % in 10 meters. Several examples at different frequencies are herein reported, and applications to high power Electron Cyclotron Heating and Lower Hybrid Heating of a plasma find a good solution using quasi-optical schemes. The wide bandwidth, the fact of having a single line needing no cooling and without requirements of high mechanical precision (as in certain waveguide components at high frequency), are other advantages of the Reflecting Beam Waveguide System (RBWS) which have been examined in this work.

The Xe spectrum in the 95-260 Angstroms spectral region, excited in TFR Tokamak plasmas, has been recorded by a grazing incidence multichannel spectrometer. Several lines in the Cu- and Zn-like isoelectronic sequences as well as a broad band (due to the superposition of unresolved transition arrays strongly mixed by configuration interaction) have been identified.

A long term ECRH program in TORE SUPRA for current drive researches is proposed. The aim of the program is twofold, namely, optimization of the rf driven current in TS by an appropriate combination of LH and EC waves and the search of current drive scenarii of relevance for the steady-state reactor. It is shown that under favourable conditions, steady-state operation can be envisioned by rf current drive with a marginally acceptable efficiency. Experimental results on selective wave absorption at down shifted frequency obtained in PLT and on current drive by EC and LH wave in WT-2 and JFT-2M are given besides the studies presented on Tore Supra.

In the first part of this work, we describe the hardware and software used to design integrated systems able to acquire, memorize, process and visualize 1024 x 1024 x 8 bits images. In the second part, we present and analyse the first realised prototype system which is a digital radiology one. After a technical and economical digital radiology study, we present the angiographic and tomographic results. In the third part, we indicate possible evolution of this system and we show how the adopted structure and developed hardware allow applications in various fields.

Spent fuel from nuclear power plants is reprocessed at La Hague reprocessing plant in France. Recovered and stored reprocessed uranium has an energy potential unutilized so far. A modelisation is proposed in this paper for evaluating the economic interest reprocessed uranium reenrichment for using it again in a power plant. After briefly recalling the fuel cycle in light water reactors and reprocessed uranium specificities, a mathematical model for multi-isotope enrichment gives a differential system governing isotopic separation. Different solutions are proposed and compared. A. de la Garza analytical model's is retained. An economic value is attributed to reprocessed uranium. Results are presented as curves for determining the sensitivity of this value to simulation parameters (natural uranium cost, enrichment required by the electricity board etc.).

Among the nuclear mechanisms used for the production of nuclei far from stability, the projectile fragmentation process has recently proved its efficiency. However, at Fermi energies, one has to take into account some collective and relaxation effects which drastically modify the production cross-sections. The spectroscopic study of very neutron-rich nuclei is very dependent of these production rates. A study of beta-delayed neutron emission which leads to new measurements of half-lives and neutron delayed emission probabilities is achieved with a liquid scintillator detector. The results which are then compared to different theories are of interest for the understanding of natural production of heavy elements (r processus).

Analysis of data collected with /sup 40/Ar beam shows strong evidence for the formation of very excited compound nuclei: (this letter will concentrate on the results obtained at 19.5 MeV/A for the /sup 40/Ar + /sup 27/Al system). Incomplete linear momentum transfer remains small and the temperatures obtained can be estimated between 6 and 7 Mev.

The stopping powers of 11 solid media have been measured for 20-95 MeV/u oxygene ions from the French GANIL accelerator. The energy measurements were made using the LISE magnetic spectrometer. The accuracy in stopping power determinations is of +- 1-2%. The data are in good agreement with semi-empirical values from Hubert et al (Ann. Phys. Fr. 5, supp (1980)) and from Ziegler (Pergamon, 1980) and with a scaling relative to He/sup 2+/ ion stopping powers, assuming fully stripped ions inside the degrader.

Current situation is presented about narrow isovectorial, non-strange, dibaryon resonances. First positive results have often been criticized for their poor statistics. It is shown in this paper that this time is over and that dibaryon existence cannot any more be discussed. Different assumptions have been made to explain the observed results; these results are reviewed; assumptions are tentatively refuted so as not to have to recall them later during a discussion on recent theories.

The inelastic of /sup 20/Ne on /sup 90/Zr and /sup 208/Pb has been studied at 500 and 600 MeV incident energies. High statistics spectra were measured at the grazing angle. For each target, spectra at the two incident energies were compared by means of cross correlation analysis. Structures were observed in the inelastic spectra, but they appeared at different excitation energies at the two beam energies and therefore cannot be identified with high-excitation energy states of the target nuclei in contradiction to the results of previous experiments. Rather they arise from the decay of discrete unbound states in the projectile-like nuclei which were excited by a one-nucleon-transfer reaction. In particular, the structures observed in the transfer-evaporation continuum of the /sup 20/Ne + /sup 208/Pb spectra appear to be mainly due to neutron emission from known discrete unbound states in /sup 21/Ne. A relatively low upper limit is given for the production cross section of multiphonon states in these systems.

We show from the comparison of the experimental angular distributions of one-neutron transfer reactions with that of the elastic scattering that a specific phase rule emerges. This elastic-transfer phase rule states that the

oscillations in the neutron transfer cross-section should be in phase with those of the elastic cross-section. This feature is independent of the angular momentum transferred. Furthermore, we show how these results can be understood through semi-classical arguments.

In a model including approximately a large set of non elastic channels, the real and imaginary potentials are consistently derived. The anomaly of the real potential which sharply increases in the vicinity of the Coulomb barrier where the imaginary potential is strongly reduced is studied in /sup 16/0+/sup 40/Ca and /sup 16/O+/sup 208/Pb systems. The results on the imaginary potential are discussed and compared to our previous calculation.

The double differential inelastic scattering cross section around the grazing angle for the /sup 40/Ca+/sup 40/Ca system is evaluated within a model where the excited states are described in terms of multiphonons. The phonon states described in the RPA are excited through the action of the mean field associated with the other colliding nucleus. The excitation amplitudes are evaluated by integrating the equations of motion along classical trajectories. The feedback on the trajectory of the multiphonon excitation is taken into account. The cross section is then evaluated within a semiquantal approximation by summing the scattering amplitudes corresponding to the various classical trajectories. The results indicate that, within the model, states corresponding to the single and double excitation of the giant quadrupole mode are appreciably excited, giving rise to bumps in the cross section. Some qualitative comparisons with the experimental data are shown.

The lasertron is a device to transform high voltage power to microwaves, and it is much like a klystron with a photocathode. The beam is bunched in the lasertron by the laser light that is modulated at the microwave frequency. The photoelectrons are produced at a cathode, and accelerated to a fairly high voltage in the gun region by an electric field. These electrons produce microwaves in the output section, which is one or more cavities that decelerate the beam with the microwave fields. The purpose of this paper is to develop a computer model of the lasertron. This model can be used to predict general trends in lasertron performance on the device parameters, and the model can also be used to design lasertrons for particular applications. The ring model of the electrodynamics in the klystron has recently been written. The main features of the ring model of the lasertron are as follows. The relativistic electron dynamics of a set of particles are followed from the photocathode through the gun region and through the output region, with time as the independent variable. The fields are summed by superposition to find the total field at each electron's position. The model is 2 1/2 dimensional. A single bunch of electrons is followed through the lasertron. The program is modular and flexible, so many of the fields can be approximated in several ways to alter the accuracy and time requirements to perform the simulation. The particles all have the same charge, so the laser light pulse is assumed to be rectangular. All processes in the photo cathode are assumed instantaneous. The beam model is a central disk surounded by rings. This combination starts at the cathode in a plane, and is repeated many times over the length of the laser pulse.

It is shown that interference effects between depolarization resonances lead to a resonance shift and to appearance of higher-order satellite resonances. Resonance shift can bias energy calibration by depolarization technique. Higher-order corrections to spin diffusion in electron storage rings are studied in the vicinity of one or two resonances and are found important only when depolarization is large. Validity of spin-matching conditions for spin rotators is also studied at higher order.

The physics of B mesons that has already been achieved and is expected to be achieved in the near future is quickly reviewed. Emphasis is put on the problems that could be left over and the case for an improved b factory machine is advocated.

It is demonstrated that a geometric interpretation of Kaehler transformations in superspace allows to construct the full action for matter and Yang-Mills fields coupled to supergravity in a concise way, both in terms of superfields and component fields.

The description of the antisymmetric tensor gauge field with Chern-Simons forms in Kaehler superspace is used to derive a particular coupling of the antisymmetric tensor to the general supergravity-matter system in terms of superfields as well as component fields. The construction is performed directly in terms of the linear multiplet. The proper duality transformations are presented at the full superfield level. General couplings are shortly discussed.

This report of the SCPRI exposes an interpretation of the principal results concerning the routine monitoring of environmental radioactivity in France: atmospheric dusts, rainwater, surface waters, underground water, drinking water, sewage water, food chain (milk, vegetables, fishes), sea water around nuclear plant sites and other sites, sediments. The activities of various radioisotopes are presented in tables. This report exposes also the results of special radiation measurements resulting from the Chernobyl accident.

This report of the SCPRI exposes an interpretation of the principal results concerning the routine monitoring of environmental radioactivity in France: atmospheric dusts, rainwater, surface waters, underground water, drinking water, sewage water, food chain (milk, vegetables, fishes), sea water around nuclear plant sites and other sites, sediments. The activities of various radioisotopes are presented in tables. This report exposes also the results of special radiation measurements resulting from the Chernobyl accident.

The general principles and mechanisms how soil gas carrying radon infiltrates from the foundation bed and subsoil into buildings are described. Recommendations as to ways of reducing the radon levels indoors are given.

We investigate double penguin-like diagrams for the B/sup o/-anti B/sup o/ mixing, a missing piece in the literature. We find that the short-distance part of these diagrams contributes <or {similar_to}% and thus is unimportant in reconciling the value of poorly determined parameters of the standard model and the most recent experimental information. We also point out the long-distance hadronic complications which leave the B/sup o/-anti B/sup o/ mixing issue to some extent open. 23 refs.

The generation of secondary DC field quantities in a non-magnetized plasma in a rectangular waveguide is studied. The generation of DC electric fields as well as the modification of the charge density of the different charge species is considered.

The activities of the Risk Analysis Group at Risoe during 1984 are presented. These include descriptions in some detail of work on general development topics and risk analysis performed as contractor.

The report should be considered a guide for the treating of human errors: for identifying their possibilities of occurrence when designing well-structured human tasks and for their improvement when they occur in reality. For these purposes a strong coupling between predictive and retrospective analysis is emphasized: In order to control human errors, post-incident analysis of cases with human errors in a given industrial plant should be performed as means of feedback from reality for the verification of results of predictive analysis and also as general means of identifying and improving such human errors which cannot be expected covered by predictive analysis. Primarily, the guide addresses people with a knowledge of the technical plant in question and involved in the safety-oriented design and improvement of human activities and without a particular human factors background. The main report describes the procedures for post-incident analysis and for Work Analysis, which is a search strategy developed for well-defined activities, e.g. test and calibration, and constitutes a formalized procedure for the pre-identification of relevant human errors leading to a lack of task result and/or to immediate effects not covered

by the lack of task result itself. Work Analysis and the post-incident analysis procedure are based on a common description system for human malfunctions. This system is explained in appendix and so are its underlying models and way of reasoning. Finally, a word index is provided for supporting the reader.

A simulation model of a hypothetical PWR power plant is described. A large number of disturbances and failures in plant function can be simulated. The model is written as seven modules to the modular simulation system for continuous processes DYSIM and serves also as a user example of this system. The model runs in Fortran 77 on the IBM-PC-AT.

Various possibilities to accelerate a frozen hydrogenic pellet by means of a constant base pressure behind the pellet are examined.

In the context of an analysis of technical quality assurance in Norwegian X-ray departments, a survey has been carried out in 21 laboratories in 4 hospitals. The tests were restricted to equipment used in general radiography, and the parameters analysed were of kV (using an electronic penetrameter), exposure time, waveform, output and automatic exposure control systems. In addition, a trial to compare overall performance in radiography and fluoroscopy was performed with a PMMP test phantom (SPRI). The survey is presented in two reports. This first one covers details of procedures and equipment. In the second report results are given and discussed. The results show that most of the equipment does function satifactorily, but also demonstrate the need to introduce quality assurance in X-ray departments.

In the context of an analysis of technical quality assurance in Norwegian X-ray departments, a survey has been carried out in 21 laboratories in 4 hospitals. The tests were restricted to equipment used in general radiography, and the parameters analysed were of kV (using an electronic penetrameter), exposure time, waveform, output and automatic exposure control systems. In addition, a trial to compare overall performance in radiography and fluoroscopy was performed with a PMMP test phantom (SPRI). The survey is presented in two reports. The first one covers details of procedures and equipment. In this second report results are given and discussed. The results show that most of the equipment does function satifactorily, but also demonstrate the need to introduce quality assurance in X-ray departments.

In the ALOK part of the large container programme (reactor safety programme), automated ultrasonic testing was done with conventional test head systems in the first phase. The test included selected fault positions inside the M4 circular weld and all fault levels of the 4/1 circular weld. The C pictures were produced online by two test techniques during each test run. The subsequent evaluation of the ultrasonic data included the production of C picture representations of other test functions, the selection of faulty areas and the cleaning up of original data in these areas by forming running time/place curves.

A position sensitive multiwire proportional counter has been developed for applications in neutron radiography and small angle neutron scattering experiments. Its sensitivity for thermal neutrons is about 50% and its spatial resolution was measured to be 5,7 mm (anode) resp. 7,9 mm (cathode). The maximal counting rate for the applied electronic system comes up to about 2 . 10/sup 4/ s/sup -1/. By means of a simplified physical model the gamma sensitivity as well as the neutron sensitivity has been calculated taking into account the energy level of discrimination. Some applications for neutron radiography demonstrate the feasibility of this position sensitive counter. With 31 figs., 4 tabs.

The first part of the report reproduces the targets, the production of the test area and other preparatory work and the filling and measurement when introducing the waste/binder mixture into the model cavern. Three short parts on the arrangement of the cavern, investigations on loosening material from the caverns and the determination of the hydration heat data during storage form the second part.

It is shown that transverse momentum conservation in the three-source Fai and Randrup statistical model does not explain the collective azimuthal alignment as observed in heavy-ion collisions at Bevelac energies.

After a single intravenous or oral application of /sup 3/H pentaacetylgitoxin (/sup 3/H-PAG) and /sup 3/H gitoxin, the elimination of the radioactivity from the blood plasma of guinea-pigs over a period of 7 days was determined. After intravenous application of /sup 3/H-PAG, the change of albumen binding of the radioactivity, its distribution between organic solvents and plasma water, its concentration in various tissues relative to its concentration in plasma water (T/M quotient) and its elimination via feces and urine, was measured. The concentration of radioactive materials in the derived gall bladder was measured for 6 hours after intravenous injection of /sup 3/H-PAG.

Aqueous solutions of RSa, DNA and solutions which contained both substances were irradiated under N/sub 2/, O/sub 2/ and N/sub 2/O. The products of radiolysis were examined by gel chromatography, where after treatment with sodium dodecyl sulphate and mercapto-ethanol, the proportion of non-covalent combinations and of disulphide groups was determined. If one irradiates RSA solutions under N/sub 2/ and N/sub 2/O, the yield of aggregate and the molecular size of the particles in the aggregate rise with the dose of radiation, until at the maximum dose of 1714 Gy, all RSA molecules are aggregated by covalent combination. Dimers are first formed under N/sub 2/, and dimers and trimers are formed under N/sub 2/O. The radiolysis of RSA under O/sub 2/ leads to the formation of protein fractions. When DNA solutions are irradiated with a dose of 857 Gy, then regardless of the existing gas condition, only DNA fractions are formed. The irradiation of sample solutions, which contain both RSA and DNA, shows that combinations of protein and nucleic acid only occur under N/sub 2/ and N/sub 2/O, but not under O/sub 2/. The decomposition of DNA under N/sub 2/ is largely prevented in the presence of protein, while under N/sub 2/O DNA is decomposed. Although the cross linkages between the DNA and the RSA were missing, irradiation under O/sub 2/ in the presence of protein only led to partial decomposition of DNA, as the primary radicals of the water were collected by the protein.

It is possible to reduce dependence on uranium supplies by the spallation technique. This technique will only become economically sensible if uranium prices rise considerably, as the capital service share of the electricity costs reaches a value of 80% in spallation reactors. One can obtain a compensated fuel balance by the spallation processes, but the acceleration efficiencies of less than 50% achieved up to now are not sufficient.

The starting point for the considerations and calculations given in this dissertation is the inevitable production of radioactive materials in the use of nuclear energy, which creates a considerable potential danger in a final store for a very long period. As one possibility of alleviating this problem, a concept for recycling the waste actinides neptunium, americium and curium was proposed. The waste actinides are separated in the reprocessing of burnt-up fuel elements and reach a further irradiation circuit. There they pass through the stages 'manufacture of irradiation elements', 'use in a fast power reactor' and reprocessing of irradiation elements' several times. In each irradiation and subsequent storage, about 17% of the waste actinides are removed by fission or by conversion into nuclides which can be reused as fuel, so that during the life of 40 years of the fast recycling reacor, the waste actinides can be reduced in mass by one half. In order to determine this mass reduction effect, a model calculation was developed, which includes the representation of the neutron physics and thermal properties of the reactor core and the storage and reprocessing of the irradiation elements.

Pionium is the state of a positive pion and an electron bound by the Coulomb interaction. It belongs to the light hydrogen-like atoms. In this thesis an experiment is described in which for the first time this exotic hydrogen isotope was formed and detected. At the Swiss Institute for Nuclear Research pions with a momentum of 45 MeV/c (E=7.2 MeV) were moderated to energies of some 100 keV.

These pions pass a 10 {mu}m thick aluminium foil whereby they capture with a probability of some percent an electron and form pionium. Behind the foil the charged particles are separated by a magnetic field and the neutral atoms trapped on a micro channel plate detector (MCP). From the time of flight between a scintillator immediately in front of the foil and the MCP's the energy of the pionium atoms is determined. In two laterally situated scintillator telescopes the muon from the pion decay is detected and later the decay positron from the muon. This multiple coincidence allows a unique identification of the pionium atoms. During a 4-day measurement 3300 pionium atoms were detected on an area of 44 cm/sup 2/ at the position of the MCP's. This corresponds to a pionium rate of 4.0(4) 10/sup -7/{pi}/sup +/e/sup -//{pi}/sub in/ or about one {pi}/sup +/e/sup -//min. If an isotrope emission distribution of the atoms is supposed directly behind the production foil 2 {pi}/sup +/e/sup -//sec is obtained. The time-of-flight distribution of the atoms agrees with Monte Carlo simulations.

Under the scope of this study, the KWU-multi-zone computer program WAVCO (Hydrogen-Distribution in the Containment), for use in hypothetical core melt accident situations has been upgraded and verified against distribution experiments performed earlier. Analyses of gas-distribution in the PWR-containment after a postulated, hypothetical core melt accident, confirm current assumptions of an almost homogeneous distribution of burnable gas. Based on the present state-of-the-art concerning gas release, a maximum H/sub 2//CO concentration of 12% vol. under low pressure conditions was calculated. Under high pressure conditions there was no evidence of ignitable gas mixture built-up, despite an approx. 8% vol. local H/sub 2/-enrichment. With 34 refs., 14 tabs., 70 figs.

The digital data as recorded by the Battelle-Institute during the integral acoustic emission test (data storage by disc), were reevaluated using particular post test analysis programs. The report outlines the essential characteristics of the acoustic source location method (KWU-SL) applied thereby. The evaluation results can be summarized as follows: Test measurements performed both on the inner and outer surface show that the KWU-SL method provides a reliable means for pinpointing of acoustic emission sources. A uniform high level of location quality is obtained for the RPV cylindrical shell as well as for the bottom part; the accuracy lies in the range of approximative twice the wall thickness and a few acoustic emission signals, originally located by the FLAIR computer program, were found by the KWU-SL method to be erroneous and have been eliminated. Most of the indications, however, proved to be correct and have only slightly be relocated. With 1 ref., 5 tabs., 10 figs.

The modelling of the transient behaviour of fuel requires the investigation of iodine and cesium release under transient conditions. The test program performed covers a temperature range from 900 to 1750degC. The main item was the investigation of the release under oxidizing conditions and at presence of Zircaloy. The reactions occurring thereby cause a strong increase of iodine and cesium release. The influence of the temperature on the release is characterized by a change of the activation energy within the temperature regime of the experimental program. With 21 refs., 2 tabs., 39 figs.

Pregnant Wistar rats were irradiated at days 11, 13 or 16 of gestation with 0.60 Gy of /sup 60/Co-gamma-radiation at a dose-rate of 0.01 Gy/min. Controls were sham-irradiated and tested simultaneously. The adult female offspring was confronted with a set of standardized operant conditioning test sessions. Food reinforcement was made contingent to the fulfillment of gradually increased learning demand. The tests were micro-computer-controlled and the data stored on flexibe disks. Performance deficits were found in the groups (N=10) irradiated at gestational days 11 or 16 with respect to the controls. The pattern of operant test performance showed a circadian rhythm in all groups but was unaffected by irradiation. The observed performance differences between groups irradiated with the same dose but different dose-rate did not reach statistical significant levels. Motor coordination and strength were also tested in juvenile

male littermates. In these tests the prenatally irradiated animals performed significantly poorer than the controls.

Within the scope R+D-task 1500 287/AO , the 1300 MWe PWR systems behaviour has been investigated in the PKL test facility under LOCA conditions (large breaks) during end-of-blowdown (EOB), as well as during refill- and reflood phases. In order to combine the EOB-phase (starting at 26 bar) with the refill- and reflood phase, the facility was modified and upgrading measures were taken to improve measurement techniques. This report gives a detailed description of the PKL-test facility, its auxiliary systems and power supply as of January 1985, test series PKL IIB. With 5 refs., 57 figs.

The present thesis describes an apparative arrangement for the measurement of the n-p polarization-transfer coefficient D/sub t/ at a mean neutron energy of 25.5 MeV and the possibility for the determination of the /sup 3/S/sub 1/-/sup 3/D/sub 1/ mixing parameter. Extensive Monte Carlo programs were developed for the optimization of the experimental arrangement and for the determination of the polarimeter properties. An unpolarized test measurement is presented as well as the course of the data evaluation discussed. A first polarized measurement yielded because of a cup current of only 30 nA as well as some technical problems at the isochronous cyclotron yet no evident result concerning D/sub t/. At a polarized beam current of 500 nA to be expected and a mean neutron polarization of P/sub n/=0.45 the n-p polarization-transfer coefficient D/sub t/ can be determined in a four-week beam-time to +-0.025 from which a fixation of the /sup 3/S/sub 1/-/sup 3/D/sub 1/ mixing parameter to +-1.0 degrees results.

The measurements at the meteorological tower provide the data for propagation calculations, which are necessary for the assessment, co-ordination and limitation of the inevitable emission during operation of reactors and laboratories. Actual meteorological values are used for propagation calculations and emission analyses. The tower also supplies the meteorological data for the research project on the spread of harmful substances in the atmosphere and environmental loading. At the same time, it is the place of emission with variable height of emission for propagation experiments. Apart from the description of the tower, measurement and climatic values are given in tables.

In the Nuclear Research Center Inchas a uranium dioxide fuel laboratory is planned and built by the AEA Cairo (Atomic Energy Authority). The layout of this fuel lab and the programmatical contents are subject to the bilaterial cooperation between Egypt and the Federal Republic of Germany. In this report the safety analysis as basic items for the approval procedure are started in detail.

Thermodynamic restrictions for the constitutive relations of an internal variable model are derived by evaluating the Clausius-Duhem entropy inequality with two different approaches. The classical Coleman-Noll argumentation of Rational Thermodynamics applied by Coleman and Gurtin to an internal variable model is summarized. This approach requires an arbitrary modulation of body forces and heat supply in the interior of the body which is subject to criticism. The second approach applied in this presentation is patterned after a concept of Mueller and Liu, originally developed within the context of a different entropy inequality and different classes of constitutive models. For the internal variable model the second approach requires only the modulation of initial values on the boundary of the body. In the course of the development of the second approach certain differences to the argumentation of Mueller and Liu become evident and are pointed out. Finally, the results demonstrate that the first and second approach give the same thermodynamic restrictions for the internal variable model. The derived residual entropy inequality requires further analysis.

The aim of this work is to analyse the behaviour of some different Advanced Pressurized Water Reactor (APWR) designs during the reflooding phase following a large break (double ended) loss of coolant accident (LOCA). The FLUT code and its most important physical models and correlations will be shortly discussed.

The major changes will be described addressing the reasons for their introduction. A special attention is given to the description of a newly developed droplet-model, which allows a better modelling of the progression of the quench front. In order to assess the updated correlations and models, many forced reflooding experiments were evaluated. The results of these post-test calculations will be shown. The calculations for two APWR designs will be then compared with that for the reference PWR, pointing out the most important differences.

Using the IVA2/005 computer code the SNR model explosion experiment SGI-09-1 was numerically simulated. The experiment consists of high pressure gas injection into a low pressure liquid pool with a free surface in a cylindrical geometry with internals. Bubble formation and pressure history as a function of time was predicted and compared with the experimental observation. A good agreement between theory and experiment was obtained. Numerical diffusion and its influence on the results are discussed.

Using the IVA2/005 computer code three dimensional effects during a LOCA for a homogeneous APWR are simulated. The formation and transport of void and droplets in a reactor vessel of the KWU-1300 type, responsible for the three-dimensional cooling of the core are shown as functions of time and space. The results prove that it is important to perform a three-dimensional analysis rather than a one-dimensional one to predict more realistic temperature distributions of the fuel rods, especially for the strong three-dimensional multi-velocity fields considered in this study.

For simple drift cells with a rotational-symmetric electric field the simulation of particle tracks by UV laser-radiation allows the exact determination of the position-drift time relation and the drift velocity in dependence on the drift path. For this the laser ionization density must be fitted to the ionization density for particles. Then the results are comparable with those reached at DESY. In the medium drift region spatial resolutions of 40 {mu}m to 50 {mu}m can be reached. An increase of the pressure to 2 bar absolute improves the spatial resolution especially for short drift paths ({approx_equal}30 {mu}m). A double-track simulation is possible by relatively simple means. The values reached with electrons however are not reached completely. With a more sophisticated beam optic and a smaller beam aperture particle tracks can be simulated more accurately. Also the evaluation procedures for the FADC data can be optimized in so far that the time resolution of the FADC's is comparable with that of the TDC's. The spatial resolutions calculated by this procedure agree with those determined from TDC data.

The author investigates the question whether under present International Law the disposal of radioactive substances in the sub-seabed (Sub-Seabed Disposal Program, SSD) is permissible. He comes to the conclusion that a general International Law rule does not exist. But the provisions of the London Dumping Convention (LDC) could be applied on the SSD-Program.

The report describes the use of /sup 252/Cf in the testing of VLSI electronic components for sensitivity to heavy ions. The source /sup 252/Cf emits alpha particles, fast neutrons and fission fragments in large numbers. The fission fragments are heavy ions which high LET makes them well suited for cosmic ray simulation experiments. The convenience and simplicity of the technique make it very attractive and have led to its widespread acceptance. The safety aspects of using a /sup 252/Cf source are considered and recommendations are made on the handling, calibration and use of the source.

The Central Interlock and Safety System (CISS) provides basic safety functions for the JET plant. It monitors the status of emergency push buttons, access doors and plant equipment and takes corrective shutdown actions in the case that plant conditions are not compatible with safe operation. CISS consists of a hierarchical network of PLCs (programmable logic controllers) paralleling the CODAS architecture. It has been successfully in operation since June 1983 and has intervened many times and halted operation to protect JET from (further)

damage or personnel against danger. The note will analyse genuine CISS failures only, and as will be shown, these failures are all due to malfunctioning of PLC hardware. All CISS failures have failed-safe and resulted in the expected shutdown action. Hence CISS failures have never resulted in a dangerous situation but they have restricted operational availability of JET.

The C particle is interpreted as a four-quark orbitally excited 'crypto-exotic' state. Further experimental tests of this configuration are suggested as well as possible searches for other states with exotic quantum numbers in the same SU(3) multiplet. Selection rules for hybrid and four-quark decays are discussed and used to propose tests to distinguish between qqq-barq-bar and hybrid qq-barG interpretations of the GAMS exotic Jsup(PC) = 1/sup -+/ eta{pi} signal.

In order to pursue crystal structure determination using neutron diffraction data, and given the wide experience available of solving structures using X-ray data, the codes used in X-ray structural analysis should be adapted to the different requirements of a neutron experiment. Modifications have been made to a direct methods program MITHRIL and to a Patterson methods program PATMET to incorporate into these the features of neutron rather than X-ray diffraction. While to date these modifications have been fairly straightforward and many sophistications remain to be exploited, results obtained from the neutron versions of both programs are promising.

Amplifiers in the charge amplifier configuration are being used extensively in the readout of solid state detectors. The majority of these amplifiers are built using a Field Effect Transistor input device. To achieve optimum noise performance, there is an important matching condition between the capacitance of the amplifier input device and that of the detector. In the paper, the matching condition is derived and the consequences are discussed.

The author explores the consequences of a mapping of the Hubbard Hamiltonian with a view to finding possible superconducting phases. The transformation pairs up all the sites and is therefore a much more natural starting point for describing a 'Spin Peierls' transition, generating enhanced singlet correlations for this pairing, than it is for describing the 'Resonating Valence Bond' state. It is shown that in the less than half filling case, an effective non-linear hopping Hamiltonian is quite useful in describing half of the electrons. This effective Hamiltonian can show a form of superconducting instability when nearest neighbour hopping is introduced to stabilise it. This superconducting phase seems to be a very unlikely possibility for the standard Hubbard model.

The paper is the Fourth Report of the Management Advisory Committee (MAC) of the Inspection Validation Centre (IVC), 1987. The Committee was set up to review the policy, scope, procedure and operation of the Risley IVC. A description is given of the technical progress of the IVC during the year 1986/87. The MAC has also considered several aspects of the design basis for the proposed Sizewell 'B' reactor as reflected by the specifications placed upon the IVC. (U.K.).

Items within the scope of EDB have been entered individually into the data base. (ACR)

Magnetic properties have been investigated for several rare-earth based, polycrystalline samples of high T/sub c/ superconductive "123" compounds with magnetic onset temperatures between 90 and 95{sup 0}K. Analysis of the susceptibility chi of samples based on Gd, Ho, and Dy indicates that the superconductive and magnetic properties are independent of one another to a substantial degree. 8 refs., 3 figs., 1 tab.

The Large Coil Task (LCT) is an international collaboration of the United States, EURATOM, Japan, and Switzerland to develop large superconducting magnets for fusion reactors. The testing phase of LCT was completed on September 3, 1987. All six coils exceeded the design goals, both as single coils and in six-coil toroidal tests. In addition, a symmetric torus test was performed in which a maximum field of 9 T was reached in all coils simultaneously. These are by far

the largest magnets (either in size, weight, or stored energy) ever to achieve such a field. 6 refs., 6 figs., 3 tabs.

This paper is a status report of the Soudan II honeycomb drift chamber project. It reports on the physics goals, present progress and future schedule of our experiment. It also includes a discussion of the angular resolution of cosmic ray muons which can be achieved in underground detectors, and in particular how to calibrate the resolution using the moon's shadow in cosmic rays. This last point has relevance in trying to understand the angular distributions in the reported observations of underground muons from Cygnus X-3. 12 refs., 9 figs.

The critical current density of powder metallurgy processed wires is determined in part by the extent of the A15 phase formation in the vicinity of the Nb/Al interface. A series of multi-layered samples was made to simulate the reactions in the P/M wires. Transmission electron microscopy was used to study the reactions between the multi-layers. Results indicate that the reactions at the Nb/Al interface depend strongly on the Nb and Al layer thickness and distribution. No evidence of the metastable NbAl solid solution formation was found. It is concluded that the Nb{sub 2}Al and the residual Nb present in the reacted P/M wires can be avoided if the Nb and Al layers are sufficiently thin and uniformly distributed with the proper stoichiometry. 10 refs., 7 figs., 2 tabs.

Structural studies have played a key role in understanding the new oxide superconductors. Neutron powder diffraction techniques have been of particular importance because of the difficulty in synthesizing single crystals of the desired quality and compositions and because of the need to accurately determine the locations and site occupancies of the oxygen atoms. The electronic properties have been shown to depend in a critical way on the structural details of the Cu-O sublattices in these compounds. The La/sub 2-x/M/sub x/CuO/sub 4-y/ (M = Ba, Sr, Ca,...) structure contains a two-dimensional square planar Cu-O sublattice with weak bonding between the layers. The YBa{sub 2}Cu{sub 3}O/sub 7-x/ structure contains both two-dimensional and one-dimensional Cu-O sublattices, commonly referred to as "planes" and "chains." Closely-related non-superconducting phases which exhibit small differences in stoichiometry or symmetry have also been studied and have provided key insights into the close relationship between structure and superconductivity in these systems. 88 refs., 6 figs.

We have made two interim assessments of the probabilistic ground-motion hazard for the potential nuclear-waste disposal facility at the Nevada Test Site (NTS). The first assessment used historical seismicity and generalized source zones and source faults in the immediate vicinity of the facility. This model produced relatively high probabilistic ground motions, comparable to the higher of two earlier estimates, which was obtained by averaging seismicity in a 400-km-radius circle around the site. The high ground-motion values appear to be caused in part by nuclear-explosion aftershocks remaining in the catalog even after the explosions themselves have been removed. The second assessment used particularized source zones and source faults in a region substantially larger than NTS to provide a broad context of probabilistic ground motion estimates at other locations of the study region. Source faults are mapped or inferred faults having lengths of 5 km or more. Source zones are defined by boundaries separating fault groups on the basis of direction and density. For this assessment, earthquake recurrence has been estimated primarily from historic seismicity prior to nuclear testing. Long-term recurrence for large-magnitude events is constrained by geological estimates of recurrence in a regime in which the large-magnitude earthquakes would occur with predominately normal mechanisms. 4 refs., 10 figs.

Microstructural characteristics of long-term-aged cast duplex stainless steel specimens from eight laboratory heats and an actual component from a commercial boiling water reactor have been investigated by scanning electron microscopy (SEM), transmission electron microscopy (TEM), small angle neutron scattering (SANS), and atom probe field ion microscopy (APFIM) techniques. Three

precipitate phases, i.e., Cr-rich {alpha}' and the Ni- and Si-rich G phase, and {gamma}{sub 2} austenite, have been identified in the ferrite matrix of the aged specimens. For CF-8 grade materials, M{sub 23}C{sub 6} carbides were identified on the austenite-ferrite boundaries as well as in the ferrite matrix for aging at {ge}450{sup 0}C. It has been shown that Si, C, and Mo contents are important factors that influence the kinetics of the G-phase precipitation. However, TEM and APFIM analyses indicate that the embrittlement for {le}00{sup 0}C aging is primarily associated with Fe and Cr segregation in ferrite by spinodal decomposition. For extended aging, e.g., 6 to 8 years at 350 to 400{sup 0}C, large platelike {alpha}' formed by nucleation and growth from the structure produced by the spinodal decomposition. The Cr content appears to play an important role either to promote the platelike {alpha}' (high Cr content) or to suppress the {alpha}' in favor of {gamma}{sub 2} precipitation (low Cr). Approximate TTT diagrams for the spinodal, {alpha}', G, {gamma}{sub 2}, and the in-ferrite M{sub 23}C{sub 6} have been constructed for 250 to 450{sup 0}C aging. Microstructural modifications associated with a 550{sup 0}C reannealing and a subsequent toughness restoration are also discussed. It is shown that the toughness restoration is associated primarily with the dissolution of the Cr-rich region in ferrite.

The local energy is so small-scaled and distributed that this energy cannot be utilized very efficiently together with conventional energy supply systems, such as solar light and geothermal energy. The Ministry of International Trade and Industry has subsidized to survey the potential of local energy business and model enterprise to be performed in each area by local government and the 3rd sector since the fiscal year of 1931, based on the fundamental study done in 1980 and 1981. As from the fiscal year of 1982, the Ministry has given interest compensation for the same and general utility enterprises on the basis of the results of the model business. Survey results of local energy development and applications (FY 1984 - 1985) are shown together with energy sources and survey details for 28 object areas. (1 fig, 1 tab)

A closely connected luminescent tube structure wherein both high light flux and compactness are simultaneously attained and a glass ceramic seal is adopted, is easy to produce; reliability and strength of the product are sufficiently secured. Its shape and dimension is as compact as an incandecent bulb, and yet the same level of brightness is obtained at the cost as low as 1/4. Fluorescent materials for the ordinary bulb color are green (La-phosphate activated with Ce and Tb) and red (Y-oxide activated with EU); for 3-wave-length daylight bulb, a blue fluorescent material (Sr-chlorophosphate activated with Eu) is used in addition. As this type of lamp is easily susceptible to the environmental temperature, different from an incandecent lamp, it requires considerations to restrict the temperature rise of the lamp or the stabilizer when an illuminating designs are to be made. (10 figs, 1 tab)

This material contains the latest data as of the year 1987 regarding petroleum demand and supply and petroleum development in Japan and all over the world. The data sources are publications of various nations' governments, materials published by the Petroleum Corporation, statistical materials from British Petroleum, and annual reports of petroleum companies. The principal data are as follows: Data about petroleum import to Japan -- amount of petroleum imported from each supplier, area, and country; data about petroleum development in Japan -- development policies, petroleum and gas production, changes in yearly development investment, and efforts for development on continental shelf and overseas; data about petroleum demand and supply in the world -- petroleum and other energy demand and supply in each area and in each country, forecast of energy demand and supply in the free world, petroleum movement between areas, changes in world petroleum prices; data about petroleum development in the world -- proved reserve, yearly changes of production, development activities, reserves and development of oil sand and oil shale, policies and outline of principal countries and main petroleum companies. (16 figs, 146 tabs)

This book was published in Jan, 1987 by The Institute of Applied Energy. This is in pair with the secondary edition which was published in Jan, 1985. In this issue, on the basis of data obtained during the recent two years, 62 additions and 6 renewals are contained; the break down is as follows: Nuclear power (36), Fossile fuel (15), Natural energy (5), Utilization of energy (6), and Energy storage (1). Main additions were in nuclear power and fossile fuel, especially coal. Concerning the price data, recent trend for crude oil, coal, natural gas, and uranium, etc. which are the typical primary energy. The objective of this issue is to summarize the results of the research activities of the Institute for the effective utilization in and out the Institute. All data contained are the already publicized ones.

The research and development system under the Chirac government has been altered from the past style of government leadership to the style of the enterprise competition and the self initiative. Budget has been strictly tight since the establishment of AFMG in 1982. Touched by the nuclear accident at Tchernobyl, concern for such nuclear matters as the radio-active pollution is quite strong among the mass-communication groups, but the people rather have strong reliance on the government measure to its safety. Mr. Chartier, director-general of the Science Bureau of AFME, pointed out at the 13th. World Energy Conference held at Cannes that the French budget for R{Lambda} of energy administration has been declining year by year. The Themis photovoltaic power generation program stopped its operation on July 1st of 1986 in spite of the success of May 17, 1983 for the successful connection to the power transmission lines. A deep geothermal water utilization plant at Meaux was developed by AFME and BRGM and is supplying water (78 `C) to 8,000homes and a power output is 96,280 KW. This is expected to expand. (5 figs, 3 tabs)

A new system was realized which had a similar level of performance yet with much lower cost. The new system, similar to the previous system, is a forced circulating type solar water heating system with annual heat collection of above 2.4 million kcal. Rate of solar penetration was 91% as a result of adopting an anti-reflecting glass with a chemical etching on the ordinary glass as a solar penetrating medium of the heat collector. Heat collection was further enhanced by a selective absorption film formed on the heat collector surface by means of a special electrolytic process. This improved the collector effeciency by 20%. A cylindrical shape of the heat collecting tank saved the space by approximately 68% than the conventional unit. Other ideas of cost saving in the construction work and maintenance saved the equipment cost of approximately 30%. (4 figs, 2 tabs)

This paper describes each new energy related item in Japanese government's draft budget for the fiscal 1986, focusing on the size, contents, and perspective of each project while performing comparison with the previous year. The amount of general accounts is 3.0% higher than that at the beginning of the previous year, but the general expenditure is lower. The energy related draft budget is as follows: The amount of special accounts for petroleum related activities is 607.9 billion yen, a 1.6% growth over the previous year; the amount of special accounts for electric power related activities is 270.8 billion yen, a 9.2% growth over the previous year; the NEDO budget for new energy related activities is 61.9 billion yen, a 4.4% growth over the previous year. This indicates the importance the government placed on new energy development. The paper quotes the budget, including funds and subsidies, (for each of the years 1985 and 1986) for each of the technical development for energy alternative for petroleum, resource development, development related project, coal and mine industry rationalization project, and alcohol manufacturing project. It also briefly describes planned activities in each project. (1 fig, 4 tabs)

This is a report on the study of orientation and a concrete policies measure for the cooporation to fulfil the energy demand in the Pacific Ocean region with its vitality and growth for the background, taking the Pacific Ocean region as the most vigorous region in the world from the economic viewpoint. In order to promote the Pacific Ocean energy cooporation from a gloval viewpoint, it is

necessary to attain economic development and energy security simultaneously with the following elements as the basic ideas entertaining following ideas: (1) Effective development of energy naturally stored in the earth throughout the world, (2) Optimum utilization of energy in both aspects of demand and supply, (3) Orderly arrangement of the environment on conditions so that the developed resources may be distributed smoothly in compliance with needs. For the purpose of drawing up the orientation and the concrete measures described above, an examination was carried out as to the following: (1) Demand and supply, and trading of energy in the Pacific Ocean region - present state and prospect, and points at issus, (2) Present situation of economic cooporation in the energy field in the Pacific Ocean region, and (3) Subjects to be tackled in the energy cooporation toward the 21th century. (12 figs, 3 tabs)

0he international environment, enterprise environment and energy environment surrounding Japan are changing their looks. In such situation, what Japan should do for the development of the world was discussed. Internationally, in the Western Pacific economical block including Japan and Asian NICs, Japan promotes the international exchange of materials, capital, technology, information and people, and creates various international public properties. Enterprisers should have global mind, and cope with the internationalization, technical innovation and information orientation which are in progress at present through international exchange, interindustrial exchange, industry-university-government exchange and so on. In the aspect of energy environment, Japan carries out the technical development of energy conservation, energy, creation and the exploration of energy resources, in this way, contributes to the stabilization of energy in the world. (3 figs, 1 tab)

This is a report on the development of a technique to assess the value of the supply of electric power generated through solar power generation and the evoluation therewith of photovoltaic power generation for the electric power suply and for general use. The main factors of the evaluation of the photovoltaic power generation as power generating equipment are roughly devided into the following three: the economic factor, the technical factor, and the social factor. In this study, the assessmant is performed by centering on the economic factor while taking the thechnical factor into consideration. Expressions for quantitatively assessing such basic factors of evaluation as capacity of photvoltaic power generation, supply capacity of generating equipment, reserve supply power of the current electrical source and reliability of the supply of the current electrical source are presented. Subsequently, physical KW values of photovoltaic power generation were calculated from the stand point of reliability of supply dealing only with the electric utility. The result showed that the KW value of the photovoltaic power generation for the peak duration of 10 hours was approximately 30% of that of the standard generation equipment (equivalent to a middle class thermal plant). (3 figs, 1 tab)

In the USA, cogeneration in the industrial sector was rather depressed since 1950. However, the system reevaluated as a practical energy conservation means after 1976. Two years later, a promotion law was issued in the Federal Congress while related enforcement regulations being stipulated by the Federal Energy Regulation Committee. From this time on, the cogeneration systems have been introduced practically. After the law was issued, the equipment capacities of cogeneration systems have been greatly increased to 27,289.7 MW up to 1986 while also increasing the equipment capacities of small-scale generation systems to 12,039.6 MW in the same period. Natural gases are used for 60% of these systems, while the fuels for small-scale generation systems comprising mainly biomass. California and Texas occupy 50% of the national total capacity approved. (3 figs, 4 tabs)

Investigation was conducted at Teuri Island to obtain basic data to utilize its water resources. While water supply is insufficient on Teuri Island, neighboring Yagishiri Island abounds in water resources. To compare the difference, survey was made on Yagishiri Island as well. The biggest difference between the two

islands was in summer time when little surface water is running on Teuri Island while many rivers on Yagishiri Island have much water. If the island has a normal amount of precipitation, it is estimated that a total of 200 m{sup 3}/day undergraound water can be used. Geologically, both Teuri and Yagishiri mostly consist of Neogene lava and volcanic breccia. Volcanic breccia in the uppermost formation is most promising as an aquifer. There is little difference in the amount of the surface running water in April. In the dry season of August, the amount is 1 against 13. The difference is caused by the difference in the amount of groundwater. This represents the extent of preciptation infiltration caused by differences in forest areas. Other causes may yet to be clarified. (22 figs, 6 tabs)

This is a report introducing how to apply an advanced information processing to resources exploration taking petroleum exploration as example. In this article, the advanced information processing is outlined confining to the two fields of computor graphics (CG) and artificial intelligence. An example of CG is given by mapping. It is possible for CG to perform mapping with the same level as the average faculty of geologists. Besides, reparation of 3-dimensional seismics and, well-to-well correlation drawings, etc. have become possible. In the field of artificial intelligence, wave shape analysis by Log Shape Analyzer, zoning by LITHO and interpretation of seismic section were developed as examples of pattern recognition. And dip pattern automatic recognition by Dipmeter Advisor provides an example of the expert system. (9 figs)

Ratio of co-generation in the European countries is ranked in the descending order from Denmark to Sweden, West Germany, UK, France. A survey was made, as per respective countries, on the policy, introduction status, system of co-generation, supply of equipments, financing, and the future prospect. Among the above countries, three countries, Denmark, Sweden, and West Germany pay more attention to the combination of a heat pump and a community air conditioning, whereas UK prospects for a compact package system by means of a gas engine. In West Germany, approximately 3/4 of the total output is occupied by the co-generation system as well as a small scale co-generation on the basis of an internal combustion engine. Concerning France, not much information is available and the introduction of co-generation system is not certain. In Denmark, 70 % of the total energy for the space heating and the hot water supply is aimed to be supplied by the community heating and the co-generation. (1 tab)

In 1986, 21st Century Energy Vision was arranged for the purpose of grasping the future trend of the energy policy and the energy industry. It is based upon the change in the energy supply structure, and the energy demand and supply situation. In this study, the long term future of international supply and demand of energy was analyzed, and the change of needs for energy due to the rapid change in demand and progress of energy utilization technology are also studied. It is hoped to realize the complex energy age (meaning that any one type of energy has some multiple supply sources) in the vision. It is emphasized that a promotion of technical development concerning the energy, establishing a suitable environment for the brisk and proper competition, and an independant international energy policy are the necessary problems to be established. (4 figs, 1 tab)

The yearly economic growth rate from 1973 to 1984 was 3.9%, whereas the industrial production index and final energy consumption grew at yearly rates of 3% and 0%, respectively. This difference between the macroscopic economic indices and the energy consumption is due to the transformation of the industrial structure, changes in types of product manufactured in various industries, increased efforts for energy saving, and higher value-added products. The transformation of the industrial structure was caused by a reduced weight of steel, chemical, and other material-oriented industries and an increased weight of manipulation and assembly industries. The efforts for energy saving have achieved an about 30% to 50% energy cut in manufacturing industries from 1973 to 1984. The causes of higher value-added products include implementation of rationalization in various industries and relatively increased

demand for higher value-added products and services. The difference between the macroscopic economic indices and the energy consumption will still continue in the future.

This report is a prospected energy demand in Japan by 2030 which was examined by Agency of Natural Resources and Energy, published in Nov., 1986. Low level estimate wherein the slimming of the energy-consuming industry and maximal acceleration of energy utilization are attained gives 520 million kl for 2000 and 660 million kl for 2030. Rate of growth is respectively 1.6% and 0.8%. High level estimate wherein the growth of the energy-consuming industry is steady and energy utilizing efficiency slows down gives 590 million kl for 2000 and 860 million kl for 2030. Rate of growth is respectively 2.4% and 1.3%. Actual consumption in 1985 was 410 million kl (1.3% growth). Electrification will steadily be accelerated and will be above 50% level in 2030. Polytically, as a whole, an optimum balance of three energy elements (security, cost, needs fitness) is regarded important.

Increase of the world energy demand during 1985 and 2000 is estimated as follows. Order of description is : type of energy, and annual production (crude oil basis, million barrels per day) and percentage. Communist countries: petroleum (7.5, 21%), natural gas (7.0, 20%), coal (10.8, 30%), hydro-power, etc. (4.6, 13%), nuclear power (5.6, 16%), total (36.5, 100%). USA: petroleum (1.2, 20%), natural gas (-,-), coal (3.3, 54%), hydro-power, etc. (0.5, 8%), nuclear power (1.1, 18%), total (6.1, 100%). Price of petroleum will stay at 20 - 25 US dollars /barrel until 1990s when OPEC may move for the price raise. Growth of energy demand in non-communist countries will be 2.1% annual average (2/3 of GNP growth rate). For USA it will be 1% (less than 1/2 of GNP growth). For communist countries it will be 2.9% (mostly natural gas). Nuclear power will increase at annual average of 4.5% in Europe and Asia. (15 figs, 2 tabs)

The energy in the world is expected to be in short supply internationally extending over a long and middle period of time. Japanese government has been taking measures to cope with the situation, and it is necessary for prefectural governments to promote energy policies keeping in touch with the national measures. This report summarizes the national and prefectural subsidy systems for promotion of energy saving by enterprises and homes, development of oil alternative energy development and utilization of local engergies, and etc. The objective, scope of application, usage of funds,agencies or organizations to make inquiries are indicated, and the current status of each system has been described. Similar data have been provided also for the financing system and tax privileges. Japan's energy policy, Sunshine Project, Moonlight Project, Development of oil alternative energy and etc. are also summarized as references. (7 figs, 42 tabs)

This is an abstract of investigation report with same title on new materials and their effects to energy in the prediction of long term from A.D.2000 to 2010. On the basis of informations obtained in the present stage, recognition of actual conditions of new materials and their effects to various industries and demand and supply of energy are described. General descriptions are as follows. (1) General description of new materials in each country. (2) Prediction per types and market, scale of new raw materials. (3) Prediction on new materials for automobile industry which is the most important industry of Japan having the largest energy consumption. (4) Concrete prediction on characteristics, demand construction and trend, and energy consumption and effect to other materials, etc. of carbon fiber, plastics, and fine ceramics, and especially on effect of ceramic engine on energy. (5) Forecast on applicable fields and market scale of biotechnology which is closely related with energy consumption although unrelated with new materials, and especially on a bioreactor. (3 figs, 25 tabs)

Pre-irradiation of stationary phase cells of Escherichia coli K-12 with broadband near-UV radiation potentiates the lethal effects of subsequent exposure to near-UV radiation plus hydrogen peroxide. Identical fluences failed to modulate killing due to far-UV radiation. These data indicate that

biologically relevant levels of hydrogen peroxide may be generated in situ upon the near-UV irradiation of cells.

Herpes simplex virus-type 1 (HSV-1) plaque-forming ability and plaque size were measured on C3H/10T1/2) cell monolayers as functions of pretreatment dose with UV light at different times before inoculation with virus, in order to determine if UV-enhanced reactivation (ER) of UV-irradiated virus, as well as associated phenomena, could be obtained in this cell system. The number of virus plaques observed (i.e. the capacity of the cells to support virus growth) and the size of the plaques were found to increase substantially with pretreatment of the cells with UV light. However, no significant ER was observed. Therefore, the mechanisms responsible for the increases in plaque size and cell capacity seem to be independent of those responsible for ER. In work by others, C3H/10T1/2 cells have been transformed by UV light at doses similar to those used in this study; the absence of ER of UV-irradiated virus in this study indicates that the mechanism underlying ER is not required for transformation.

Retinoblastoma (RB), cancer of the retina, occurs in an inherited form which not only predisposes the patient to bilateral RB, but also to the risk of developing secondary tumors of mesenchymal origin. These tumors often arise in areas that were exposed to ionizing radiation during therapy and fibroblasts derived from patients with hereditary RB have been reported to be more sensitive than normal to the killing effects of ionizing radiation. Therefore, we compared diploid fibroblast cell lines derived from two hereditary RB patients with those of three normal persons for their sensitivity to ionizing radiation-induced transformation to anchorage independence. There was no detectable difference between the RB cells' and the normal cells' response to the transforming action of the {sup 60}Co. Both kinds of cells showed a linear, dose-dependent increase in anchorage-independent cells from 100 to 800/10{sup 6} cells assayed.

It is proposed that hyperbaric oxygen fails in the clinical situation due to a high proportion (greater than 33%) of hypoxic cells in human tumours. The means of overcoming this problem are reviewed. Additional to hyperbaric oxygenation, moderate hypothermia (30{sup 0}C) to allow redistribution of oxygen in the tumour is proposed. A system of externally controlled intravenous anaesthesia has been developed for the single-subject hypervaric cylinder. Pharmacological vasodilatation is induced in the anaesthetised patient who is then fluid loaded and cooled. Initial single-sensitising treatments are advocated. Twenty-nine patients with advanced mouth cancer have completed a course of this treatment, of whom five of nine were free of disease after 2 years and 10 of 21 at 1 year, with three intercurrent deaths. Fifteen have experienced local failure. This approach would appear to be practical, safe and promising.

An approach to using hyperbaric oxygen with radiation in a clinical situation has been described in the preceding paper in this issue. To ascertain whether there might be a change in the relative biological effectiveness of radiation on normal mammalian tissue treated under conditions of hypothermia and hyperbaric oxygen, the acute reaction to radiation of pig skin was studied. A single dose enhancement ratio at the erythema reaction level of 1.4+-0.08 was obtained when compared with irradiation at normal body temperature in air. The authors studied also a series of antioxidant enzymes in rat liver and lung after exposure to hypothermia and hyperbaric oxygen. Enzyme changes were such as to combat oxygen toxicity which might develop as a result of the pre-treatment.

The paper assesses the risk of cancer in the United Kingdom resulting from the Chernobyl reactor accident. Earlier data on cancer risk due to exposure to ionizing radiation are summarized (ICRP, UNSCEAR, BIERIII]. These data are then used to estimate cancer fatalities due to exposure to Chernobyl fallout deposits. (U.K.).

The maximum single dose of the 2-nitroimidazole hypoxic cell radiosensitiser Ro 03-8799 is limited to 1 g/m{sup 2} by the occurrence of a well characterised acute syndrome of sweating, nausea and mental changes. In an attempt to increase the tolerable dose, the clinical toxicity of the racemic mixture was compared

with that of the R- and S-enantiomers of Ro 03-8799. Twelve patients received escalating alternate doses of racemic mixture and R- or S-enantiomer, the dose levels being 0.25 g/m{sup 2}, 0.5 g/m{sup 2}, 0.75 g/m{sup 2} and 1.0 g/m{sup 2}. Careful monitoring of the acute syndrome failed to demonstrate any consistent differences between racemic mixture and either enantiomer. This would suggest that the toxicity is not mediated via any specific central nervous system receptor. It is concluded that separation of Ro 03-8799 into its enantiomers will not enable a clinically useful increase in dosage.

This is the first report of skin damage caused by an interaction between ifosfamide and radiation. Because of the very severe acute skin reaction and the late woody fibrosis seen in this patient the authors no longer administer ifosfamide during a course of radiotherapy.

The time required between well-separated pairs of doses of X-rays (e.g. 2F/day) for repairable damage to be apparently completed increases with dose per fraction and with the {alpha}/{beta}ratio, even when the underlying half-life is invariant.

The paper presents a diary of events of a regional Medical Physics Department of the Northern Regional Health Authority, following the Chernobyl reactor accident. The duties of the department included: monitoring members of the public returning from Eastern Europe, monitoring milk and rainwater, radioassay measurements, as well as providing independent advice and reassurance to the public.

A method is described for calculating r.b.e. values for normal tissues at risk in clinical neutron beam therapy. This is based on the assumption that with high l.e.t. radiations the slope of the cell survival curve is steeper, mainly in the initial or low-dose region. This effect is quantified by using two coefficients, one (epsilon) to produce a proportionate increase in the initial slope, and a second (eta) determining the change in the terminal slope (Dsub(o)) of the survival curve. Analysis of published experimental data shows epsilon to be a variable quantity, different for different tissues; epsilon is larger when the survival curve has a large shoulder or slope ratio (rho). By contrast, eta is relatively constant (for a given beam) and less dependent on the tissue or end-point studied. For low doses, the r.b.e. approaches epsilon, which can be calculated given eta (characteristic of the beam) and rho (characteristic of the relevant tissue) [epsilon = eta + rho(eta-1)]. This provides a useful approximation to the clinical r.b.e. for specific tissues relative to conventionally fractionated low-l.e.t. photons.

A report is given of a cancer mortality study in Caithness, Sutherland, Orkney and Shetland between 1958 and 1982. For Caithness and Sutherland, the numbers of male deaths from all kinds of cancer was significantly less than the numbers expected from figures for Scotland as a whole; for females no difference was observed; the parish of Latheron showed an excess of leukaemia cases. For Orkney and Shetland, the total number of cancer deaths for both sexes was significantly less than for Scotland as a whole. In Shetland, there was an excess of lymphatic leukaemia in Northmaven based on four deaths observed. In Orkney, one parish showed an excess of lymphatic and haematopoietic cancers.

A critique is given of the pamphlet produced by the Health Information Service on radiation protection and the biological effects of radiation. It is alleged that the pamphlet contains a mixture of accurate statements and serious distortions and errors; examples of each are given.

One hundred and forty-five patients with limited stage small lung cancer were included in a randomized trial to evaluate the effect of chemotherapy with or without chest irradiation. Seventy-six patients were allotted chemotherapy alone while 69 patients received the same chemotherapy plus radiotherapy, 40 Gy in split-course, administered in weeks 6 and 10 after the initiation of chemotherapy. The chemotherapy consisted of lomustine, cyclophosphamide, vincristine and methotrexate. The combined regimen tended to be more efficacious

with respect to tumour control at the expense, however, of increased toxicity which per se, eliminated a potential improvement of the overall therapeutical results.

One hundred and forty-three women with primary breast carcinoma were treated by radical radiotherapy associated with artificial pneumothorax to include the breast and lymphatics en bloc with large opposed fields. Surgery was restricted to local excision or drill biopsy. Most patients received a tumour dose of 5200-5600 cGy in 19-22 fractions over 4 weeks and were followed up for at least 5 years. Local control was achieved in 87% of T{sub 1}, 52% of T{sub 2}, 27% of T{sub 3} and 23% of T{sub 4} tumours. For T{sub 2} tumours local control was greater following excision biopsy (75%) than when surgery was more limited (21%). Acute morbidity was mostly minor and self-limiting. The commonest permanent late complication was restriction of shoulder movement in 20 patients. This method although safe and feasible does not offer significant advantages over conventional techniques.

The experience of treating 30 patients with sarcomas of soft tissue and bone with d(15)+Be neutron irradiation is reported. The local control of measurable soft-tissue sarcomas was 38.5% (minimum follow-up 2 years), which is similar to that expected after photon therapy. The radiation morbidity was unacceptably high (50%). Bone tumours did not respond well; in only one out of nine was lasting local tumour control achieved.

A man aged 33 with poorly controlled hypertension who had been treated with radiotherapy and combination chemotherapy for testicular teratoma 8 years earlier was found on arteriography to have 75% stenosis of the left renal artery and occlusion of the right renal artery. The stenosis was dilated by transluminal angioplasty and the hypertension adequately controlled. Patients who develop high blood pressure after abdominal radiotherapy with or without chemotherapy should be investigated for renal artery stenosis.

A patient who developed a partial relapse of Bell's palsy following superficial radiotherapy to a basal cell carcinoma in the temple is reported. Nerves injured by Bell's palsy may be more susceptible to radiation induced damage.

Fractionated gonad doses of 0.35 Gy cause marked temporary reduction in sperm count; fractionated ovarian doses up to 1.5 Gy have no apparent effect in women aged 20 to 30. Single testicular doses of 0.5 to 3 Gy cause aspermia; return to pre-irradiation sperm counts occurs about 30 months after single doses of 2 and 3 Gy. The ovary also has a recovery capacity, particularly in women under 40. Type B spermatogonia are the most radiosensitive germ cells for cell killing. Later stages are more radioresistant, forming a transient population in the total male reproductive life. Following radiation-induced sterilisation, fertility is restored if enough spermatogonia survive to repopulate the seminiferous tubules. Radiation effects on female fertility are explained on the basis of reduction in a fixed oocyte pool. Doses needed to induce artificial menopause are higher in younger women because their ovaries contain larger oocyte numbers. Particular fractionation regimes decrease the threshold dose for permanent male sterility. It has been inferred that human testes could tolerate 1 mGy per day indefinitely without fertility impairment. In female experimental mammals, fractionation reduces fertility damage. Fractionation may also have a protective effect on the human ovary, depending on age and total dose. (U.K.).

Three organs, the skin, eye and testis are potentially at risk from poorly penetrating radiations such as beta particles or low energy X-Rays. They may be preferentially irradiated in fields with steep depth - dose gradients and thereby dictate radiological protection procedures. Since there is not a wide margin of safety in the annual permissible dose limits for these organs it is important to have clearly defensible methods of dose assessment. This requires both an adequate understanding of the radiobiology of these organs and the availability of experimental techniques for measuring doses at various depths near the surface of the body. This paper reviews the current state of knowledge in this field, drawing partly on information from two recent CEC workshops on

the 'Dosimetry of Beta Particles and Low Energy X-Rays' and 'Radiation Damage to the Skin'. It is concluded that protection criteria for the limitation of skin dose are in need of revision.

Six out of 30 patients who underwent thyroid ablation with {sup 131}I during the period 1975-85 developed acute oedema of the neck within 48 h of the therapeutic dose. The condition was painless and responded well to treatment with corticosteroids. The early onset and absence of pain distinguish this complication from radiation thyroiditis. Dosage calculations and thermoluminescent-dosemeter measurements of the dose at various points on the anterior surface of the neck of a patient with a toxic adenoma of the thyroid treated with {sup 131}I were in fairly good agreement with one another and confirmed that the oedema of the neck could not be a direct effect of irradiation on the extrathyroidal tissues. It is suggested that this phenomenon may be a hypersensitivity reaction associated with massive destruction of thyroid tissue.

Induced recessive mutations can cause harm by (1) partnership with a defective allele already established in the population; (2) partnership with another recessive mutation induced at the same locus; (3) the formation of homozygous descendants, that is, identify by descent; and (4) heterozygous effects. Calculations based on a combination of data from observations on human populations and from mouse experiments suggest that an extra genetically significant dose of 1 cGy X or {gamma} irradiation received by each parent in a stable population with a million liveborn offspring would induce up to 1200 extra recessive mutations. From partnership effects, about one extra case of recessive disease would be expected in the following 10 generations. Homozygosity resulting from identity by descent could not normally occur until the fourth generation after exposure but, on certain assumptions, about ten extra cases of recessive disease would be expected from this cause by the tenth generation. In the same period, about 250 recessive alleles would be eliminated in heterozygotes given 2.5% heterozygous disadvantage. These deleterious heterozygous effects should not be combined with those of dominants, as has been done in some previous risk estimates. It is considered unlikely that many radiation induced recessives would show heterozygous advantage. Certain dominants should be excluded from calculations of mutational risk because they are unlikely to be maintained by mutation.

A report of the Tizard lecture by Lord Marshall, chairman of the UK CEGB, on the health risks associated with the disposal of radioactive wastes is given. The risks from inhalation and ingestion of various types of radioactive waste disposal are compared to the risks from radioactive material occurring naturally in the average garden soil in the UK occupying one tenth of an acre. The relative potential health risk from inhalation of coal ash is also contrasted.

Eight patients, one male and seven females, with no pre-existing hypothalamic-pituitary disease, who developed symptoms of hypopituitarism following cranial irradiation for nasopharyngeal carcinoma were studied 5 years or more after radiotherapy. All were GH deficient. Four of the patients with no GH response during insulin tolerance tests (ITT) showed increased GH in response to synthetic human growth hormone releasing factor (GRF-44). Four patients had impaired cortisol responses to ITT, and gradual but diminished cortisol responses to ovine corticotrophin releasing factor (CRF-41). There was no significant difference between mean peak increments in response to ITT and those in response to CRF-41. TSH responses to TRH were delayed in five and absent in two patients; four of these had low free T4 index. Prolactin was raised in all seven women and increased further in response to TRH. Two patients had impaired gonadotrophin responses to LHRH. None of the patients had clinical or biochemical evidence of diabetes insipidus. These data suggest that post-irradiation hypopituitarism in these patients results from radiation damage to the hypothalamus leading to varying degrees of deficiency of the hypothalamic releasing or inhibitory factors.

The long-term sequelae of external pituitary irradiation alone or in combination with surgery and/or bromocriptine therapy have been studied in 14 patients with large prolactinomas over an observation period of 6-22 years (mean 13 years). It was concluded that radiotherapy, alone or in combination with surgery and bromocriptine, effectively decreases prolactin secretion and tumour size in patients with large prolactinomas at the expense of other anterior pituitary function. Circulating prolactin levels are a poor marker of residual tumour volume.

Angiosarcoma is a malignant tumour of the vascular endothelial cell that rarely occurs in the head and neck. Two cases are presented arising in the nasopharynx after radiotherapy. The role of radiotherapy in carcinogenesis is considered with reference to the delay between treatment of a primary head and neck tumour and presentation with the second primary.

Two patients with carcinoma of the penis were treated with interstitial radiation. They were cured of their disease for 17 and 21 years respectively and then developed radiation-induced tumours.

Sperm analysis and serum hormone measurements (LH, FSH, testosterone) were performed in 29 patients after orchiectomy for seminoma before and after irradiation. Before radiotherapy 14 of 20 orchiectomised patients were azoospermic or had impaired spermatogenesis. A minimum sperm count was found 1 year after radiotherapy with gradual improvement up to 2 years. The recovery of sperm cell production was impaired most in patients with pre-treatment sperm counts < 3 million/ ml. Serum testosterone remained at low normal levels throughout the observation period. The mean serum FSH was increased 1 year after radiotherapy but returned to normal in 50% of patients within 3 years after treatment. This post-treatment increase in FSH was significantly correlated with increased pre-treatment FSH but not with the gonadal dose, which was 1 to 3% of the target dose. Severe disturbances in spermatogenesis, observed 2 to 3 years after radiotherapy for early seminoma, are likely to be the expression of a highly impaired pre-treatment sperm cell production and only to a lesser degree dependent on the irradiation of the remaining testicle.

The clinical trials of fast-neutron therapy for head and neck cancers conducted at the MRC Cyclotron Units at Hammersmith Hospital, London and the Western General Hospital, Edinburgh, have been thought to have produced conflicting results. This study was undertaken as an attempt to identify and to understand these apparent differences. The trials were not contemporaneous and differed in stage of disease as well as in parameters of radiation dosage. Moreover, they compared the use of poorly understood quality of radiation generated by inadequate equipment with standard megavoltage X radiation and telecobalt gamma radiation. General conclusions about the value of neutron therapy cannot be drawn from this limited review. (U.K.).

The effect of tangential and direct irradiation on regional lung function in 22 consecutive patients with breast cancer, treated by post-operative irradiation 3 months prior to examination. The tangential technique (total dose 32-36 Gy, < 5 Gy to the lung) was employed in eight of the patients, while the direct technique (total dose 40 Gy, 5-20 Gy to the lung) was used in the other 14. In the tangentially treated group, there was no impairment of the ventilation or perfusion of the irradiated lung compared with the contra-lateral lung. Thorax radiographs were normal. In the group treated by the direct technique, there was a reduction in both ventilation and perfusion in 12 patients (p < 0.01). Thorax radiographs were abnormal in only seven of these 12 patients. In both groups, regional leakiness of the lungs was evaluated as the pulmonary clearance of inhaled nebulised {sup 99}Tcsup(m)-DTPA. Results were inconclusive, due to variable smoking habits. It is concluded that regional lung function was not significantly affected by the tangential technique, contrasting with a pronounced and harmful effect of the direct technique. (U.K.).

In this pilot study of multiple treatments in 1 day given over a continuous period of 12 days, the technique has proved to be a practical one. Immediate

reactions have not been unduly troublesome and tumour responses have been encouraging. Five of seven patients with advanced bronchial carcinoma have shown evidence for complete regression and this compares favourably with only seven complete regressions seen in 62 similar patients previously treated by radiotherapy, (Saunders et al, 1984). To this can be added the complete regression observed in the primary site in all four patients with advanced head and neck tumours.

Anorectal manometry was done in 10 men with chronic radiation proctitis and symptoms of urgency, frequency, and occasional incontinence of faeces. They were compared with 10 asymptomatic age and sex-matched controls. The maximum resting anal canal pressure and the physiological sphincter length were significantly lower (p<0.01) in the irradiated group. The rectosphincteric reflex was absent in one patient and showed abnormalities of recovery in four others, who had received radiotherapy. The squeeze pressure of the external sphincter was not significantly different. These results indicate that dysfunction of the internal anal sphincter may contribute to patients' anorectal symptoms after pelvic radiotherapy. Histological evidence suggests that damage to the myenteric plexus is mainly responsible. The manometric function of the external sphincter remains relatively unaffected.

A 5-day-old female patient was found to have large hereditary retinoblastomas in the posterior pole of each eye. The patient received radiation treatment over a 39-day period, with each retina receiving 4600 rad. Two weeks after the complete treatment the tumours had regressed to approximately one-quarter of their original size. By 14 weeks following completion of radiotherapy the patient had developed in each eye extensive iris neovascularisation with progressive closure of the filtration angles, secondary glaucoma, and retinal detachments resulting from fibrovascular proliferation on the retinal surface. Radiosensitivity studies were from separate conjunctival biopsies obtained before and after radiation. These showed a Dsub(O) (calculated survival curve parameters, defined in the Methods section) in the exponential growth phase of 110 prior to radiation and a postirradiation exponential growth phase Dsub(O) of 70. Karotype studies showed several chromosomal abnormalities following radiotherapy. The clinical course and pathology findings are thought to represent an unusually severe orbital and ocular response to radiation therapy. These findings are consistent with our hypothesis that some patients with hereditary retinoblastoma may have a defect in the accumulation repair of x-irradiation induced DNA damage.

A novel method is presented for the accurate determination of the restricted dose mean LET (cut-off energy = 500 eV) of any photon or electron radiation spectrum, relative to {sup 60}Co. The method is based on the development of a new and more accurate initial recombination model for electrons in high-pressure ionisation chambers. A suitable chamber has been built and measurements in accordance with the requirements of the present theory have been performed, for monoenergetic photon sources of 5.9, 40, 60, 140, 660 and 1225 keV. Restricted dose mean LET values were derived with an accuracy of 10-15% and are in good agreement with theoretical values as well as with microdosimetric experimental results. The new method provides a useful tool for characterisation of the quality of unspecified photon or electron fields of any energy and is expected to make a practical contribution to the general problem of the determination of the biological effects of photon or electron radiation fields.

Based on the Third James Kirk Memorial Lecture given to the Scottish Radiological Society on 8 Jun 1985. The author limits the discussion to atrophic and degenerative reactions elicited by radiation and exemplified by dermal and pulmonary fibrosis, nephropathy and lesions of the large bowel. Attention is drawn to the difficulties of unifying the framework of pathological studies of vascular damage with the assumption of cellular biologists that it is the instantaneous level of clonogenic survival which determines the incidence and severity of large-scale damage.

Three cases of postradiation retinopathy are reported. The findings are analysed. The exudates described by many authors are really infarcts of the choroid lobules. Chorioretinopathy is proposed as a better descriptive term, and three types are suggested. Diagnosis of the condition is important to spare unnecessary enucleation, as the infarcted areas may resemble a recurrence. Predisposing factors are discussed.

This paper reports the results of anorectal manometry and electrophysiological studies of the pelvic floor in eight patients who had undergone anterior resection of the rectum with mucosal proctectomy and colo-anal sleeve anastomosis for radiation rectal injury. The group comprised six women and two men (age range 61-84 years, mean 71 years). Six bladder carcinoma patients had received small field (10 x 10 cm) external beam radiotherapy (5500 cGy in 20 treatments over 4 weeks); two cervical cancer patients had been given whole pelvis, external beam radiotherapy supplemented by a single caesium implant (cumulative dosage of 9500 cGy to the vaginal vault, equivalent to 7500 cG to point A).

Twenty patients with soft tissue sarcomas arising within previously irradiated fields have been analysed. The initial radiation dose ranged from 8.8 to 70Gy, comprising either orthovoltage or megavoltage treatment. The latent interval following radiotherapy ranged from 7 to 45 years (mean 16.8 years). The commonest histological subtype was malignant fibrous histiocytoma. Four patients required forequarter amputation. The 5-year survival was only 14 per cent. The high morbidity and mortality accompanying post-radiation sarcomas must be borne in mind when the choice between therapeutic options for potentially curable cancers is finely balanced.

The paper reviews thermal reactors including water reactors ie PWR and BWR, gas cooled reactors, Candu reactors, steam generating heavy water reactors, and Soviet Union's RBMK. The fundamental differences between these reactor types are outlined, as well as their relative importance and contribution to world energy production. Reactor safety and electricity due to nuclear power are briefly discussed. (U.K.).

A guide to manufacturers, consultants, engineers and specialist companies serving the nuclear industry is given. A listing of national and international organisations is followed by a company address section and a classified guide. A summary of the fuel cycle supply and demand picture of OECD countries is presented. There is an overview of world nuclear capacity statistics and a summary of each country's power reactor programme. Power reactors are listed by country giving general information such as capacity, location, owner-operator, etc, and by type giving detailed technical data. An alphabetical listing provides cross reference to these sections. Load factors and performance trends for the twelve months to June 30th 1986 and over plant lifetimes are reviewed.

Emergency planning and accident recovery are currently very much in the spotlight. Simulation technology, integrated with the provision of fast, timely information, can ease the problem of making decisions in the middle of a crisis.

The reactor trip simulation environment (RiTSE) system enables operators to predict whether future actions, procedures or design changes might cause a trip.

While the Japan Atomic Energy Research Institute prepares to decommission the country's first reactor, the Nuclear Power Engineering Test Centre is developing techniques to decommission commercial plants during the 1990s.

Nuclear Engineering International's first quarter review of the Western World's power station achievements is presented. Load factors for the 12 months to the end of March 1986, together with lifetime load factors are given. Figures are given for performance, by reactor type and also by country.

For a simple model of batch loading in an LWR with a linear reactivity - burnup relation, it had earlier been shown that the transient cycle in which 1-Mth of the fuel elements were withdrawn per cycle converged to a steady cycle. This

analysis is extended to a fuel management strategy where M, the number of elements withdrawn, is not a factor of the total number of elements. It is shown that cycle times still converge.

This paper examines the fracture instability of a pipe, fabricated from a ductile material such as 304 stainless steel, in which a circumferential cross-section contains two symmetrically situated through-wall cracks, the pipe being subject to bending deformation. The theoretical analysis, which is based on the tearing modulus procedure, demonstrates the extent to which a multiple-cracked pipe has a greater tendency towards instability than a pipe containing a single through-wall crack.

Steps which can be taken to mitigate the effects of severe accidents have been studied in Sweden. A containment depressurization and filtering system fitted at Barsebaeck is briefly described. The other ten Swedish reactors are to have improved protective measures against releases in the case of a severe accident. Alternatives to the large Barsebaeck filter are at present being considered.

Recent results from the S.M. Stoller Corporation's Opec-2 database suggests that there is a trend in the United States towards improved pump seal performance. The reasons behind the decline in frequency of LWR seal failures are considered.

A filtered containment depressurisation system, Filtra, has been installed at Barsebaeck in Sweden. Experiments carried out to verify the depressurisation and filtering functions are described. Details of the installation, including the filter and the vent system are given.

A new scheme for constructing reload patterns for BWR cores has been developed. It is obtained essentially by rotating the axes of reflective symmetry currently used for reload patterns through 45{sup 0}. The high values of worths of control elements during their in-sequence withdrawal for taking the core to criticality are found to be reduced by this approach. The calculations have also shown that the new scheme leads to improved safety through higher shutdown margins, while a more uniform distribution of worths over control elements can reduce thermal shocks to the fuel. It is expected to result in higher thermal margins and hence ease of operation.

The principal conclusion of the Layfield report on the Central Electricity Board's application to build a pressurized water reactor at Sizewell in Suffolk, is that permission should be given, because of the overriding national interest in maintaining the supply of electricity. However, there is still continuing debate about the relative merits of PWR and AGR reactors. Also uncertain is the situation arising from political change that may arise following a general election. In spite of the Labour party's rejection of a nuclear contribution to British energy needs, such a policy is unrealistic. The construction of Sizewell-B would also provide employment for many people. These two issues may force any future Labour government to reconsider its anti-nuclear position. (U.K.).

The Layfield report (published following the Public Inquiry into the application of the Central Electricity Generating Board to build a pressurized water reactor at Sizewell in Suffolk) is summarized. The PWR reactor design is described and illustrated. There were thirteen recommendations made in all, covering the three aspects investigated; safety, economics and the environment. The report's main recommendations are that permission should be granted for the construction of the PWR but not the second internal access road proposed. However, although government consent for the PWR at Sizewell-B has been given, the objectors have continued the controversy, and, with a general election possible, (1987) the construction of Sizewell-B is still uncertain. (U.K.).

A statement from the Secretary of State for Energy was read out. A short debate followed. The statement concerned the decision to allow the construction of a pressurized water reactor at Sizewell in Suffolk. In the report of the Inspector at the Public Inquiry on this issue, a recommendation is made that consent be given. Issues that have arisen since the Inquiry ended, - the accident at

Chernobyl and changes in electricity demand and fossil fuel demand have been taken into account by the Secretary of State in coming to his decision. (U.K.).

The Secretary of State for Energy informed the House of his decision to allow the Central Electricity Generating Board to construct a nuclear power station using a pressurized water reactor at Sizewell in Suffolk. The Board, local planning authorities and the objectors will be notified of the decision. The Inspector at the Public Inquiry into the building of Sizewell-B, in his report, recommended that consent be given. Since the Inquiry closed the accident at Chernobyl has occurred - this has been taken into account in making the decision, as have the recent changes in electricity demand and fossil fuel prices. Following the statement by the Secretary of State there was a debate which is reported verbatim. This raised issues of design safety, the fast-breeder reactor development programme and the environmental impact of Sizewell-B. (U.K.).

The House was asked to take note of the Inspector's Report on the Central Electricity Generating Board's application for consent to build a pressurized water reactor at Sizewell, Suffolk. The public Inquiry lasted for over two years. The Inspector, Sir Frank Layfield, recommended in his report that consent be given. The decision rests with the Secretary of State for Energy. This was an opportunity for the members of the House of Lords to debate the issues involved. The debate lasted nearly four hours and is reported verbatim. The main areas of debate were on the safety aspects of the PWR and on the economic arguments in favour of Sizewell-B. (U.K.).

In 1983 the Kraftwerksschule or Power Plant Training Centre in Essen, West Germany, placed an order for the design, construction and delivery of a power plant operator training simulator which replicated the controls of the 1300 MWe Grafenrheinfeld PWR plant. The simulator was designed and supplied by Krupp, Atlas Elektronik GmbH and is described in the following article.

Nuclear reactor safety has become an issue of major concern in reactor design. The Swedish 'Pius' PWR (Process Inherent Ultimate Safety) is an 'inherently safe design'. That is, it is intended to maintain its integrity against all possible equipment failures, operator errors or even malicious tampering, without needing any engineered safety systems or human action for as long as a week after an incident. It is now being designed in modular form to allow a standardized approach to any power requirement. Each module consists of one reactor core, one steam generator, one recirculation pump and associated components, entirely submerged in borated water. The reactor is illustrated and its basic principles explained.

The paper reports the findings of Sir Frank Layfield's report on the Sizewell Inquiry: the Inspector recommended that the PWR station should be built. The recommendation was based on the national need to maintain an economic and continuous supply of electricity, which could be provided by the PWR at Sizewell. Also the inquiry team were confident in the safety of the proposed reactor. The Inspector made a number of additional recommendations on topics which included: training of operators, annual dose equivalent for the Sizewell workforce, safety criteria, radioactive waste management, and generation costs. (U.K.).

The report produced by Sir Frank Layfield following the Public Inquiry into the proposed building of a PWR reactor at Sizewell in Suffolk is debated. The Public Inquiry lasted over two years (Jan 1983 - Mar 1985), the report summarising the evidence took nearly two years to write. The recommendation of Sir Frank Layfield is that consent for the building of the reactor is given. The debate, which lasted 6 hours 20 mins is reported verbatim. It covers all aspects of the report including safety (with the accidents at Chernobyl and Three Mile Island being mentioned often) and the economic case now that the price of oil has fallen considerably. The purpose of the debate is consultative -an opportunity for members to express their views to the Secretary of State for Energy with whom the decision finally rests. (U.K.).

An analysis of the likelihood and the consequences of 'degraded-core accidents' has been undertaken for the proposed Sizewell B PWR. In such accidents, degradation of the core geometry occurs as a result of overheating. Radionuclides are released and may enter the environment, causing harmful effects. The analysis concludes that degraded-core accidents are highly improbable, the plant having been designed to reduce the frequency of such accidents to a value of order 10{sup -6} per year. Tbe building containing the reactor would only fail in a small proportion of degraded-core accidents. In the great majority of cases the containment would remain intact and the release of radioactivity to the environment would be small. The risk to individuals have been calculated for both immediate and long term effects. Although the estimates of risk are approximate, studies to investigate the uncertainties, and sensitivities to different assumptions, show that potential errors are small compared with the very large 'margin of safety' between the risks estimated for Sizewell B and those that already exist in society.

Following the public inquiry into the building of a PWR type reactor at Sizewell in Suffolk, the Inquiry Inspector, Sir Frank Layfield, has issued his report. It recommends that the PWR is built. However, the actual decision rests with the Secretary of State for Energy, but there will be a parliamentary debate first. The key recommendations of the Layfield report are given. The future of nuclear power in the UK is reviewed assuming that the Sizewell-B PWR project is allowed to proceed. The commercial reactors now in operation are listed and an estimate of future nuclear power generation made.

A process flow model of procedures performed during typical plant outages has been applied to supplement the usual accident sequence initiating events, such as loss of offsite power, in a probabilistic risk assessment model of a nuclear plant. This method models the time-dependent plant conditions and activities not encountered during power operations in a typical pressurized water reactor. The advantages of this method, a brief description of the model and a discussion of the resulting accident sequences for a shutdown plant are presented.

The event-tree analyses of the Angra 1 nuclear power plant probabilistic safety assessment were performed by means of the explicit method of event-tree modelling of shared-equipment dependencies, from which some insights were drawn. At first, we discuss in this paper the effects of collapsing equal impact vectors (from the quantification point of view also). The second feature discussed is related to a critical analysis of the dependency matrix concept in view of a counterpart to it - namely, the GO methodology in the context of modelling intersystem dependencies. Finally, we discuss the possibility of using our computerized event-tree analysis methodology for assessing the unavailability of the involved standby safety systems, most of which are recognized to be noncoherent structures.

The paper concerns the design work carried out on Sizewell-B nuclear power station, in anticipation of a favorable ministerial decision to proceed. The design work includes a complete model of the proposed plant to assist in the planning process, and the safety features which provide built-in redundancy should the plant system fail. In addition every part of the design relating to the reactor and its servicing had to be environmentally and seismically qualified. Specifications of the primary containment surrounding the reactor pressure vessel and its containment are briefly given. (U.K.).

The Central Electricity Generating Board's commitment to a high reliability of non-destructive examination (NDE) has been translated into a set of requirements for Sizewell B that are substantially more stringent than those generally applied to pressurized water reactor steam generator inspection. An important feature is the responsibility that is placed on the manufacturers to ensure that design and fabrication of pressure parts take account of these NDE requirements. The impact of these NDE requirements on design is the main theme of this Paper.

Risk assessment for postulated severe nuclear reactor accidents must be based on a systematic, consistent approach. Improper or questionable grouping of accident

sequences into release categories for the purpose of risk appraisal can lead to errors in the calculation of offsite consequences of as much as an order of magnitude. The importance of consistent grouping is demonstrated by an analysis of the partial risk appraisal of a Virginia Electric and Power plant. In this analysis, the number of release categories required is reduced and accident sequences are reordered into more representative release categories. This leads to a significant lowering of the probability curves for exceeding dose rates.

In a method for testing a normally closed check valve connected in series with an isolation valve at the outlet of an accumulator tank in a passive injection system for supplying liquid to a reactor cooling system in a pressurized light water nuclear power system when the pressure is abnormally low, at the cold shutdown the pressure upstream and downstream of the check and isolation valves are adjusted such that the upstream pressure is higher than the downstream pressure and isolation valve is then opened and again closed whereby proper operation of the check valve is verified by recording pressure and level changes, using high accuracy pressure guages, of the liquid in the accumulator tank and comparing the recorded measurements of pressure and level during each test of the check valve with preoperational test results and certain acceptance criteria.

As part of the process of introducing the PWR to Britain, a coolant pump test facility is being planned. The basic testing capabilities of the facility and its design are described.

Because the construction of Angra 2 in Brazil was delayed Kraftwerk Union installed its simulator in F R Germany where it was used for the training of the Brazilian instructors who later helped in the training of operators for German and Spanish stations. Since the simulator has been installed in Brazil, it continues to be used by KWU for training German operators.

Microprocessor-based reactor protection with automatic testing facilities and control room display is being fitted to all Electricite de France's 1300MWe units. An improved modular design will make the system suitable for the N4 reactors and three-loop units.

The Chernobyl accident, although it occurred in a reactor of the RBMK type has also focused attention on the design and safety of Soviet PWRs. Interestingly, some of the consistently best reliability figures in the world have been recorded by two Soviet designed reactors - the PWRs at Loviisa in Finland.

The Vandellos II PWR is under construction at present, and commercial operation is scheduled for December 1987. Details of the planning and construction of the reactor are given. Technical data and a cutaway drawing are included.

A method for forming a sealed coupling between two bodies each body presenting an abutment surface, the bodies being arranged so that their respective abutment surfaces are axially adjacent one another and define a space therebetween in which a deformable gasket is disposed. An axial external force is applied to the bodies for compressing the abutment surfaces together against the gasket to form a seal between the bodies and the bodies are immobilized relative to one another while the external force is being applied to the bodies so that sufficient compression will be maintained by the abutment surfaces to preserve the integrity of the seal when the external axial force is withdrawn. The external axial force is then withdrawn, leaving the two bodies coupled together via the seal.

A fission product scrubbing system for a nuclear reactor containment building includes a water tank which is disposed in the containment building and provided with a dividing wall extending into the tank for separating said tank into a first and a second compartment adapted to be placed in communication with the outside environment via pipe. The tank is filled with water to a level above the lower end of the dividing wall to normally close the communication path from inside the containment through the tank to the outside environment and a standpipe extends from the containment space into the second compartment and has

an opening in the containment and flow distribution holes arranged in the second compartment below the water level and at a height above the lower end of said dividing wall such that gases passing from said containment space into the standpipe are discharged from said distribution holes through the water in said second compartment then through a pipe to atmosphere.

The technique development for the non destructive examination (NDE) of critical areas of steam generator and pressurisers on a small pressurised water reactor (PWR) system, is described. Problems arise during the ultrasonic inspection of thick section austenitic stainless steel welds, austenitic to ferritic transition welds and thermal sleeve forgings. Optimum conditions have been established to achieve a worthwhile examination in terms of test sensitivity, area coverage and analysis of test results. Similarly, optimum test conditions have been established for the eddy current examination of ligaments associated with headers and heater pockets. Representative test blocks containing artificial defects were used for both the ultrasonic and eddy current technique development trials. Inspections using purpose built manipulators were carried out due to access constraints and in order to minimise man radiation dose levels.

Laboratory experiments performed at Brookhaven National Laboratory have shown that the concentration of boric acid to a moist paste at approximately the boiling point of water can produce corrosion rates of the order of approximately 3.5mm per year on bolting and piping materials, which values are consistent with service experience. Other failure evaluation experience has shown that primary coolant-lubricant interaction may lead to stress corrosion cracking (SCC) of steam generator manway studs. An investigation was also performed on eleven lubricants and their effects on A193 B7 and A540 B24 bolting materials. H{sub 2}S generation by the lubricants, coefficient of friction results and transgranular SCC of the bolting materials in steam are discussed.

An analysis is presented which evaluates the tax depreciation advantage which results from the increased rate of fuel depletion achieved in the current low-leakage fuel-management LWR core reload designs. An analytical fuel-cycle cost model is used to examine the important cost parameters which are then validated using the fuel-cycle cost code CINCAS and data from the Maine Yankee PWR. Results show that low-leakage fuel management, through the tax depreciation advantage from accelerated fuel depletion, provides an improvement of several percent in fuel-cycle costs compared to traditional out-in fuel management and a constant fuel depletion rate.

Modelling to depict the location and nature of the radiation measurements needed before surveys are undertaken can save personnel exposure and improve the quality of the radiation data itself, as experience at Three Mile Island 2 has shown.

In special experiments performed in a PWR-NPP low-frequency neutron noise effects were found to be induced by local coolant boiling. A model for describing this phenomenon is developed. It is based on the assumption that integral void fluctuations are the neutron physical perturbation source. The void fluctuations themselves depend on primary noise sources (fluctuations of inlet temperature, coolant flow rate, reactor power) which are estimated with a thermohydraulic model from the axial dependence of temperature noise signals. The theoretical results are compared with measured values. It is shown that the low-frequency neutron noise can be used for boiling monitoring in PWRs.

A method of automated derivation of failure symptoms was developed as an approach to computer-aided failure diagnosis in a nuclear power plant. The automated derivation is realized using a knowledge representation called the semantic network (S-net). The purpose of this paper is to demonstrate the applicability of the S-net representation as a basic tool for deriving failure symptoms. If one can generate symptoms automatically, the computer-aided plant safety analysis and diagnosis can be performed easily by evaluating the influence of the failures on the whole plant. A specific description format

called a 'network list' was introduced to implement the knowledge of the structure of the plant. The failure symptoms are derived automatically, based on the knowledge of the structure of the plant, using a PROLOG-based database handling system. This approach allows us to derive the failure symptoms of the plant without using conventional event-chain models (e.g. a cause-consequence tree) which are subject to human errors in their design and implementation. Applicability of this method was evaluated with a simulation model of the dynamics of the secondary system of a PWR.

At the Sizewell Inquiry the Central Electricity Generating Board (CEGB) presented one of the most comprehensive cases in favour of a nuclear power development ever seen at a public forum in Britain. At the end of the 340 day Inquiry however, and despite CEGB protestations that their case remained robust, the case for Sizewell B is far from convincing. The economic case, despite being argued on the narrow terms put forward by the Board, is highly dubious, and it is probable that Sizewell B would cost the taxpayer considerable sums of money over its lifetime. For additional capacity to be ordered ahead of need, the economic case needs to be watertight. This is not the case for Sizewell B. The safety of the PWR was a major issue at the Inquiry, with a clear requirement to demonstrate that the PWR could achieve British Safety Standards. This has not been demonstrated at the Inquiry. Major safety issues such as risk assessment, the behaviour of components under LOCA conditions and pressure vessel integrity remained contentious throughout the Inquiry. Radically differing conclusions were revealed between the Board and objectors, as a result of either utilising different data, or different interpretations of the same data. It is clear that the Board appeared to take a consistently optimistic view on safety, concluding that Sizewell B was likely to be virtually the safest PWR ever built in the world. Such optimism does not appear justified on the basis of evidence presented at the Inquiry.

The safety of the Hinkley Point power station is questioned as, it is claimed, it is sited on a geological fault. The issue of whether this was known about at the time of building or not is discussed. However the main point is whether the Berkley and Bradwell Magnox stations should be allowed to continue to operate beyond their planned lifetime as they are not built to withstand seismic shocks. Although their recent safety reviews have shown they could withstand a seismic shock of O.1G the Nuclear Installations Inspectorate (NII) current safety requirements demand that nuclear plant should be able to withstand a 0.25G shock. The advisability of allowing the safety standards to be waived for these old power stations is challenged.

Trawsfynydd nuclear power station discharges into an inland lake rather than the sea. The levels of liquid discharges of Cs-137 and Co-60 into the lake and their levels in the lake mud are monitored, the former by the Central Electricity Generating Board, and the latter by the Ministry of Agriculture, Food And Fisheries (MAFF). The levels of Co-60 and Cs-137 in the mud quoted by MAFF are lower than those found in samples taken by Friends of the Earth. The discrepancies are discussed and possible explanations given. One suggestion is that there may be corrosion problems in the plant. The reliability of official monitoring data is also questioned. Of particular concern is the assessment of the critical group effective dose.

If nuclear turbines are re-bladed and overhauled off-site, it usually takes 16 weeks. Currently, reactor outages are scheduled for 8 weeks so that the turbine overhaul adds an expensive delay. However, recently (1987) the three low pressure turbine rotors of the 335Mw No 4 turbo-alternators were re-bladed in-situ in only 22 days. This work is described. The key to the speed of completion was the moment weighing system used to match the characteristics of new blades with those of the old. This eliminated the time-consuming final rotor balancing during recommissioning. When the turbines had been stripped, other areas and components were tested and repaired as necessary.

The decommissioning of the Windscale advanced gas-cooled reactor requires the design of a robot or manipulator to enter the reactor core and cut up the core

into pieces that can then be loaded into concrete-filled boxes and disposed of as nuclear waste. Existing equipment is not entirely suitable so the machine is being designed specifically for the job. A British firm has been chosen to supply the equipment, which will have joy stick control, and will be delivered by mid 1988. Six months development work, then a year of trials will follow, before the dismantling process will start. The machine, its operation and the remote viewing provision are discussed. (U.K.).

The necessity for low-levels of impurities in the feedwater of AGR-type reactor boilers is discussed and the design and operation of a condensate polishing plant described. Control of pH, suitable types of resins and their regeneration, and future trends in design and operation are discussed.

The paper on nuclear decommissioning was presented by Dr H. Lawton to a meeting of the British Nuclear Energy Society and Institution of Nuclear Engineers, 1986. The decommissioning work currently being undertaken on the Windscale advanced gas cooled reactor (WAGR) is briefly described, along with projects in other countries, development work associated with the WAGR operation and costs. (U.K.).

This brief newspaper article describes the uses to which irradiation can be put in food processing, and discusses in outline the following drawbacks: 1) the destruction of vitamins and fats 2) the increased risk of food poisoning by elimination of moulds and yeasts giving warning smells, before killing bacteria 3) the risk of recontamination 4) the present insufficient knowledge of radiolytic products. Attention is drawn to the problems of detection, control and labelling.

The dynamics and stability of a rigid cylindrical body oscillating about a hinge in a coaxial cylindrical duct containing flowing fluid are considered in this paper. A previously developed analytical model, in which the fluid-dynamic forces exerted on the oscillating cylinder had been determined by means of inviscid flow theory, is extended to take into account the unsteady viscous effects of a real fluid flow, in an approximate manner. It is shown that there exists a critical location of the hinge: if the cylinder is supported upstream of that point, then it remains stable at all flow velocities; however, if it is supported downstream of that location, then negative-damping oscillatory instability is possible for flow velocities sufficiently large to overcome the positive restraining mechanical damping of the system. The critical location of the hinge depends on the relative width of the annular passage with respect to its mean radius. By comparing inviscid and viscous flow theory results, it is shown that inviscid theory generally underestimates stability, by a margin increasing with the narrowness of the annulus.

A method of Structural Group Analysis (SGA) was used to characterize feed and liquid products from catalytic hydroprocessing using a commercial Ni-Mo catalyst. Comparison of the structural profiles revealed significant changes in the concentration of various structural groups. SGA is a promising tool for investigating chemical changes in complex reacting systems. 17 refs., 5 tabs.

The hydropyrolysis of hardwood and softwood derived black liquor was studied to develop material balance data and to investigate the potential yield of phenolic oils that might be obtained as chemical by-products of a kraft pulp mill. Hydropyrolysis reactions on softwood liquors were found to be more efficient in char formation than those on hardwood liquors. The yield of extractible phenolic oils was low, around 20-30 percent of black liquor organics, but the yields of simple phenols determined by gas chromatography were found to be even lower at 1-5 percent on black liquor organics. 10 refs., 7 figs., 2 tabs.

A review is given of all reports presenting significant new information on adverse reactions to radiological contrast media, which have appeared from July 1st 1985 until June 30th 1986. (Auth.). 76 refs.; 3 tabs.

A review is given of all reports presenting significant new information on adverse reactions to radiological contrast media, which have appeared from July 1st 1984 until June 30th 1985. (Auth.). 54 refs.

A review is given of all reports presenting significant new information about adverse reactions to radiological contrast media, which have appeared from July 1st 1983 until June 30th 1984. (Auth.). 55 refs.

The residual solids derived from the aqueous phase liquefaction of two tropical wood species were characterized. The liquefaction process comprised the following steps : preparation of an aqueous suspension of milled wood, preheating at 135/sup 0/C, sudden decompression through an orifice (delta P=17.2 MPa), reaction at 80-230/sup 0/C and rapid quenching. The residues were analyzed by two methods : acid hydrolysis and elemental analysis. The quantification of the monosaccharides present in the residues allowed the solubilization profiles of both hemicelluloses and cellulose. The elemental composition of the residues is related to the severity of the process and it becomes a solubilization index for the hemicelluloses and the lignin. The chromatographic analysis of the gaseous phase after liquefaction resulted in the determination of CO/sub 2/ as the only gas produced up to 230/sup 0/C. Kinetic first order models represented well the solubilization of the hemicelluloses and the CO/sub 2/ formation. 19 refs., 7 figs., 4 tabs.

The Danish natural gas project and its overall political and economical foundation has every year, since its was passed in 1979, been the cause of a general political discussion. The decision process and the grounds for decision were soon dominated by narrow economical considerations and evaluations. The growing parliamentary support for the project were not corresponded by an increased support from the population, because the economical debate raised doubts about the project. It is striking that there were not made any intensive or continous analysis, to help the overall decision making, neither of the organizational factors nor of how the project was to be. (SM). 36 refs.

With the drive-slip-regulating system (ASR), it has been possible to improve the adaptation of the motor vehicle to the human capability of the driver. Together with the antilocking system (ABS), the ASR system makes the vehicle controllable even under the most inclement road conditions. There is very high stability when cornering, no skidding if too much acceleration is given for a moment, no swerving, skid safety, optimum forward drive by means of automatic limited-slip differential, easier starting off, reduction of tyre wear friction and wheelspin noises. These tasks are achieved by processing the signals from the rev sensors allocated to each of the vehicle's wheels in an electronic control device for the ASR hydraulics in such a way as to influence wheel-slip so as to maintain a stable direction as described. Copious illustration is added to the description of structural, functional and performance characteristics of ASR. (HWJ).

Radioactivity is certainly not limited to hermetically sealed nuclear reactors or research laboratories. Radioactivity and radiation are a part of our daily life. The article is intended to explain basic terms of radioactivity, the sources of radioactive radiation and the dose rates emitted by them. The radiation from cosmic radiation and terrestrial radiation, the radiation doses in the vicinity of power stations and the genetically significant annual dose are specially described.

The first wall and plasma interactive components of a fusion power reactor are subjected to heavy irradiation of high energy neutrons and high heat flux during normal operation. An extremely high heat flux is deposited in the components during a major plasma disruption categorized as abnormal operation. As a consequence of the event the components melt and solidify resulting in deterioration of the material, high residual stress, metallurgical change and initiation of small cracks. Quantitative evaluation of the consequence of plasma disruption is required to maintain the structural integrity of the components and predict their lifetimes. In the present study the whole process of melting, evaporation and resolidification is analysed using a newly developed computer

code based on FEM. In addition, the elastoplastic thermal stress in the heated region during the event is described including residual stress. An experiment was carried out to verify the validity of the code.

The time-space finite element method has been applied to one-dimensional non-steady heat conduction problems. By theoretical analyses based on the condition number of the relevant coefficient matrix, the time-space method has been found to be much more precise and stable than the Crank-Nicolson method. This has also been confirmed by several numerical analyses including the thermal problems of the first wall. As an application of the time-space finite element heat conduction analysis, the thermal ratchetting of the first wall has been analysed. By comparing the numerical results with the provisions of the ASME Code Case N-47, it has been found that N-47 cannot be applied to the thermal ratchetting of the first wall subjected to repeated plasma disruption.

Ferritic stainless steel, hereafter called HT-9, is a prospective candidate material for the first wall of a fusion power reactor because of its high resistance to irradiation swelling due to 14 MeV neutrons. The large increase of the transition temperature has been proven to be in a range of 50/sup 0/C even for a neutron fluence of more than 50 dpa. However, since it is magnetized in a magnetic field, it experiences magnetic stress due to magnetization when it is used in the field. The magnetomechanical behaviour is not simple because its relative permeability is very high ({approx_equal}1000) and the B-H curve is nonlinear and followed by saturation of the magnetization. Beam-plates of HT-9 and mild steel were provided to carry out tests on the magnetomechanical behavior and compare it to the theoretical prediction. The theoretical prediction of the mechanical behavior was made for the configuration of the beam-plate based on non-linear numerical analysis of magnetization. The field distribution of the finite specimen is very different from that of an infinite specimen. It is also found that the deformation is proportional to the squared field for a very small applied field and increases monotonously to a peak. For a specimen with small inclination to the incident field, the deformation decreases very rapidly after the peak.

This study has been performed for the development of limiter and divertor plates. Their thermal and thermomechanical behavior were examined in heat load experiments with an electron beam facility, and were compared with analysis results. Graphite was proven to have a high thermal shock resistance. Its erosion thickness and thermal contact conductance were also studied. Copper alloy with coating and graphite brazed to metal were tested, and their feasibility was demonstrated for use as limiter and divertor plates of an advanced-type concept.

Cyclic thermal tests were performed on tungsten using the 120 keV Neutral Beam Test Stand at IPP, Nagoya University. A maximum heat flux of 8.8 kW/cm/sup 2/ was first applied for 56.7 ms to large samples for a total of 5 cycles. Many surface microcracks were observed after two thermal shocks, but only a few active cracks grew further in a direction almost perpendicular to the heated surface with an average growth rate of about 0.2 mm/cycle. Thermal shocks of 50.4 ms were next applied with an average heat flux of 8.2 kW/cm/sup 2/ for a total of 23 cycles. Active cracks grew in the plane lying about 3 mm below the heated surface. No visible cracks were produced in one of the four samples, but cracking occurred after cutting the sample into four identical blocks. The thermal shock cracking was restricted in the region where grain growth had occurred.

A tungsten-copper (W-Cu) duplex structure is the reference divertor plate design concept for the Fusion Experimental Reactor (FER). In the present study, a durability test of the W-Cu duplex structure against thermal cycling was performed. A tungsten disk was bonded to a copper disk by means of brazing or direct casting. The tungsten surface of the test piece was periodically heated by a high temperature argon plasma jet. Before and after the tests, the test pieces were examined with the aid of a scanning electron microscope and the Knoop hardness was measured. Grain boundary microcracks were observed after 200

and 1100 thermal cycles in brazed tungsten samples which contained a small amount of nickel and phosphorus. A cast tungsten specimen subjected to 2200 thermal cycles also contained microcracks. However, microcracks were not observed in a brazed tungsten sample containing an extremely small amount of impurities for thermal cycles up to 3700 times. Microcracks were observed in the brazing material of this test piece. None of the test specimens were broken. It is found that brazing is a valid bonding method and that W-Cu duplex structure, especially with high purity tungsten, is able to endure a practical number of thermal cycles.

To perform simulated plasma disruption experiments, a heat source which can provide fast rise and high heat flux on a target surface is required. An existing electron beam facility has been improved to provide higher heat fluxes uniformly over a wider area by installing a high speed beam rastering system. The beam rastering coils can provide a beam oscillation angle of 4.4/sup 0/ with a frequency of up to 400 kHz. The high frequency ensures temporal uniformity of the heat flux on a test surface. Triangular wave shaped current is supplied to excite the coils to provide spatially uniform heat flux over a test surface. Using this electron beam facility, we can provide uniform heat fluxes as high as 160 MW/m/sup 2/ on an area of 13 mm x 13 mm, and 20 MW/m/sup 2/ on 38 mm x 38 mm.

Lifetime analysis of fusion reactor first walls and divertor plates is performed by (1) a one-dimensional analytical plate model, and (2) a two-dimensional elastic-plastic finite element method. Life-limiting mechanisms and the limits of applicability for these analysis methods are examined. Structural design criteria are also discussed.

What are the benefits generated for Aboriginal people by mining projects like the Ranger Project? Are these projects likely to fulfill the expectations of Aborigines who support the controlled exploitation of mineral resources on their land? This article examines the economic impact of the Ranger uranium project on Aboriginal people. Its principal aim is to provide detailed information on the use of royalty-related payments made to traditional owners as a result of Ranger's operations, and the consequent employment, training and social service opportunities for Aborigines.

The State Council of the German Democratic Republic ratified the convention on physical protection of nuclear material which was signed on 21 May 1980 and deposited with the Director General on 5 February 1981. The convention entered into force in accordance with its article 19 on 8 February 1987. The German and English texts of this convention are presented.

The authors report very high {sup 234}U/{sup 238}U ratios in hydrothermal manganese crusts recovered from the Sanghihe island arc system in the West Pacific. Such ratios, about twice that of normal seawater, confirm a low-temperature hydrothermal supply of uranium, which is best explained by leaching of the underlying rocks by the hydrothermal fluids and deposition together with the manganese oxides before mixing with seawater. This suggests that the {sup 234}U/{sup 238}U in seafloor deposits may be used as a tracer of low-temperature hydrothermal reactions in the ocean crust.

The effects of two depth topography configurations on the dispersion of contaminant from an outfall in shallow water are investigated theoretically. Firstly, a sharp cross-stream depth change, with uniform water depth and current velocity on either side of it, is considered, and results from a model study of the diffusion of cooling water from Heysham power station outfall are taken into account. The second configuration is that of a uniformly sloping beach with a longshore current.

The plume of primordial {sup 3}He seen at a depth of about 3 km in the North Atlantic during the GEOSECS program in 1972 was observed again in the vicinity of the Charlie-Gibbs Fracture Zone. Most evidence suggests that the Fracture Zone is not the source of this helium, but no feasible alternative can be

identified. A series of stations on a transect from 25{sup 0} to 45{sup 0}W at an average latitude of about 52{sup 0}N shows three distinct cores of high tritium water (Labrador Sea, Denmark Straits and Iceland-Faroes waters) as well as evidence of recirculated Antarctic Bottom Water-Denmark Straits Water near the floor of the western extremity of the Fracture Zone. Tritium concentrations across this section are everywhere in excess of pre-nuclear era levels, indicating some degree of deep-water communication with the surface ocean on decade timescales.

The authors report the {sup 10}Be and Be contents of 22 sediment samples of lacustrine silt from the Wilson Creek section of Mono Lake, California. The section spans about 20-35 kyr BP and contains a record of a geomagnetic excursion for which the relative palaeointensity is estimated from the ratio of natural remanent magnetization to anhysteretic remanent magnetization. The {sup 10}Be contents of the excursion samples are somewhat higher than the average of non-excursion samples. It is clear however that geomagnetic effects are not the sole cause of the observed variations.

Outline summary of a report prepared under contract to the DOE: Research Priorities and UK Estuaries: An Overview identifying Research Requirements. Topics considered include the study of radionuclides released into the NE Irish Sea from BNFL, Sellafields, differences in the isotopic composition of stable lead in various sediments, the concentration and distribution of 'hot particles' derived from BNFL in the Irish Sea and adjacent areas, together with attempts to separate hot particles from sediments, and the composition and properties of marine surfaces in relation to uptake and loss of radionuclides, particularly in relation to the common mussel, Mytilus edulis. The problem of the presence of transuranic radionuclides in the bottom sediments of the NE Irish Sea is considered. Profiles of radioactivity are being developed at the shelf-break in order to determine the transfer of radionuclides from the sea surface to the deep sea and to coastal waters; organisms examined include phytoplankton, zooplankton and crustacea (shrimps). Organisms such as Acantharia have been examined to determine transfer of elements and radionuclides to skeletal structures eg Sr, Ba and Si. (U.K.).

Measurements of helium isotopes in the ground waters and natural gases of sedimentary basins reveal that some possess a major component of mantle-derived helium, apparently related to their mechanism of formation. Neogene basins formed by loading do not involve introduction of significant mantle helium, whereas those formed by extension do.

This book aims to review the occurrence and causes of occupational cancer and is aimed at assisting medical and safety staff, management and health and safety representatives. It is presented in the following chapters: 1) Epidemiological method 2) Agents causing occupationally induced cancer, including radiation 3) Occupations associated with risk of cancer 4) Aetiology of cancer 5) Control of occupationally induced cancer, research, prevention, legislation, national and international bodies, control of specific occupational carcinogens, including irradiation. (U.K.).

The difficulties of quantifying the effect of low-level LET radiation, the shape of dose-response curves and whether the present permissible levels of exposure are soundly based are the issues raised in the conclusions to this brief section which is dealt with under the following headings: health professionals, laboratory staff, luminous dial painters, miners including uranium mining, iron-ore workers, nuclear power, including the Hanford Nuclear Plant and Portsmouth Naval Dockyard, U.S.; national mortality data in relation to U.K.A.E.A. workers, and chromosomal aberration studies of English dockyard workers and thorium workers. (U.K.).

Concern has been expressed recently about apparent increases in the incidence of leukaemia amongst young people living in certain geographical areas. We analysed the incidence of childhood leukaemia in South-East Scotland (excluding North-East Fife) from 1970 to 1984. There was a significant geographical variation in

incidence of ALL with an excess in Fife concentrated in a small area of one district partly balanced by a relative decrease in Edinburgh. We feel that the variation is unlikely to be an artefact of geographically biased mis-diagnosis.

Three pieces of evidence in the debate on the effects of low-dose radiation are discussed. These are evidence from the television programme, 'The Nuclear Laundry' which showed that the incidence of childhood cancers close to the Sellafield reprocessing plant is greater than the national average, the findings of the Black Committee set up by the Government which concluded that the levels of radiation in the area were far too low to be associated with such an increase, and evidence from the Oxford Survey of Childhood Cancers which suggests that even a small dose of ionizing radiation may be sufficient to initiate a disease process which leads to a cancer death any time in the following 10, 20 or 30 years. The conclusion is that the risks from low dose radiation must be reassessed in the light of new evidence. (U.K.).

Several personal case histories of people who, the author claims, were contaminated by radiation, are related. These people either worked at Windscale or were in the vicinity when the fire at Windscale in 1957 caused a radiation leak or else they had jobs which brought them into contact with contamination. Many have died of cancer, caused, it is claimed, by the contamination. In the early days of nuclear power not as much was known about radiation protection and the permitted levels of exposure were higher than those of today. The public, too, were generally unaware of the potential dangers. (U.K.).

This first report from COMARE deals briefly with the background to the Black Advisory Group Report and the nature and sources of the new information that has become available; it considers how the new data affect the conclusions of the Black Advisory Group Report. It does not reassess the epidemiological data, but rather concentrates on how the new data affect the dose and risk estimates, following as far as possible the same methods as were used in the Black Advisory Group Report.

A study was conducted in the Netherlands, from a nationwide register of childhood leukaemia (1973-1980). Controls were matched with cases for year of birth, sex and place of residence. Information about exposures of the mother to potential risk factors in the year before and during pregnancy was collected via mailed questionnaires. Analyses concerned data on 519 patients with acute lymphocytic leukaemia and 507 controls. An association between maternal subfertility and childhood leukaemia might be suggested by several findings. A history of two or more miscarriages (OR 1.6; 95% Cl 1.0-2.7) and fertility problems (OR 6.0; 95% Cl 0.9-38.2) were more frequently reported among mothers of cases. Use of oral contraceptives (OC) was significantly higher (OR 1.3; 95% Cl 1.0-1.8) and the duration between discontinuation of OC and the relevant pregnancy was significantly longer. The OR for threatened abortion during the relevant pregnancy was 1.6 (95% Cl 1.0-2.6) and the related use of 'drugs to maintain pregnancy' was 1.9; 95% Cl 1.0-3.5. Among known risk factors, an increased OR for diagnostic irradiation was confirmed (OR 2.2; 95% Cl 1.2-3.8). No association between childhood leukaemia and prenatal viral infections, smoking and alcohol was found.

The paper concerns a reply to criticisms of the author's lecture ''Can radiation be good for us'' by A. Stewart :1985, Letter. Nucl. Eng. May.p.84]. Studies of cancer rates and background radiation dose amongst populations of Americans, Japanese and Chinese are discussed. (U.K.).

The report by the National Radiological Protection Board in the Medical Research Council's study of some of the UKAEA workers is criticized. It is argued that the cancer risk estimates of the International Commission on Radiological Protection are seriously wrong, and that as they are used as a basis for radiation protection standards in the UK, these standards now need revising. The subject is discussed under the headings: broad-based campaign; all radiation is a hazard; building networks (of scientific and medical expertise). (U.K.).

A book has been written, aimed primarily at radiologists, on the adverse reactions of drugs, chemicals, radiation and other environmental hazards in the chest, gastrointestinal tract, renal tract, skeletal system and soft tissues and finally the skull and central nervous system. The book indicates the valuable contribution of radiology to the diagnosis of these conditions. Five sections pertaining to the delayed radiation injuries observed in all these body areas following radiotherapy treatment and one section on delayed radiation injuries occuring due to the medical use of radium. Thorotrast and colloidal gold have been selected and indexed separately.

Delayed radiation effects in the lungs, ribs and mediastinum following radiotherapy of the chest region are briefly described. Radiographic images are presented illustrating fibrosis of the lungs and radiation rib fractures following radiotherapy for bronchial and breast carcinomas respectively.

Acute and delayed radiation effects in various organs of the gastrointestinal tract following radiotherapy treatment of the pelvis are briefly described. Radiographic images are presented illustrating radiation enteritis due to radiation injuries in the bowel and stricture of the colon following radiotherapy of the cervix and bladder respectively. The use of angiography and computerized tomography in the assessment of radiation injuries in the gastrointestinal tract are briefly discussed.

Delayed radiation effects in the kidneys and urinary tract following radiotherapy of the pelvis and the use of Thorotrast in retrograde pyelography are briefly described. Radiographic images are presented showing radiation damage to the bladder twenty-three years after radiotherapy for carcinoma of the cervix.

Delayed radiation effects in the skeletal system following radiotherapy treatment are briefly described. Radiographic images are presented showing radiation osteitis, radiation sarcoma, skeletal growth impairment and osteochondromas following radiotherapy of various parts of the body.

Delayed radiation effects in the skeletal system are briefly described, due to the use of radium by radium-dial painters or in therapeutic radon injections, Thorotrast in diagnostic imaging techniques and therapeutic radioactive colloidal gold injections.

Delayed radiation effects in the skull and central nervous system following radiotherapy of the head and the use of Thorotrast are briefly described. Radiographic images are presented illustrating radiation necrosis in the jaw and skull following radiotherapy of the head regions.

Fifty-six patients, 30-47 yr of age, with leukemia in relapse received allogeneic marrow transplants from HLA-identical siblings. All patients were treated with cyclophosphamide (120 mg/kg) and 7 daily fractions of 2.25 Gy of total body irradiation (TBI) for seven consecutive days. Nine patients (16%) are currently alive, free of disease, 324-845 days from transplantation. Actuarial relapse and survival rates at 2 yr were 56% and 9.5% respectively. These data were not remarkably different from those in previous studies using 10 Gy of TBI administered as a single dose. Thirty patients were randomized to receive methotrexate (MTX) and 26 to receive cyclosporine (CSP) as postgrafting prophylaxis for acute graft-versus-host disease (GVHD). Probability of developing significant acute GVHD by day 100 post-transplant was 71% for patients in the MTX group and 45% for patients in the CSP group (p<0.05). Probability of relapse was 37% for patients in the MTX group and 70% for patients in the CSP group (p<0.05). Transplant-related deaths were more frequent in the MTX group and leukemic deaths more frequent in the CSP group although this may have been related to an uneven distribution of high-risk patients. Long term disease-free survival was comparable.

The purpose of this paper is to evaluate the relevance of the Black Report to the communities whose situation it was primarily addressing - the communities of the towns and villages around Sellafield in West Cumbria. The authors are

concerned (1) with examining in what ways and to what extent the Black Report was received by these communities, (2) with examining the extent to which these communities were reassured by the report's message (and, prior to that, in need of reassurance); and, (3) with revealing and examining the terms in which local people themselves speak about the report and related issues. Through a comprehensive linguistic analysis of these aspects the authors are concerned, inter alia, to recast the research priorities and methodology of work on risk 'perception'. The analysis and evaluation draws on an original local attitude survey and is set against a number of contextual points.

Hind feet of group of female rats aged 7, 14 and 52 weeks were X-irradiated at 20, 25 or 30 Gy. Hyperthermia (42.5{sup 0}C for 1 h) was carried out immediately following irradiation using either 'wet' or 'dry' heat, by immersion in water or fluorocarbon liquid. Results demonstrated that 'wet' heat produced a consistently greater enhancement of the irradiation damage than 'dry'. The thermal enhancement ratio for irradiation plus 'wet' heat was approximately 1.5 and for irradiation plus 'dry' heat 1.17 to 1.39. Immersion of the feet in fluorocarbon liquid at 37{sup 0}C did not significantly modify the irradiation response of the skin. The lower thermal enhancement ratios obtained using immersion in fluorocarbon liquid at 42.5{sup 0}C are close to those obtained in large animal studies and similar to the limited amount of data from clinical studies where microwave or ultrasound heating techniques were used. It has been demonstrated that there are large age-related differences in the response of the rat foot skin to irradiation alone. It has also been shown, using rats of the same age, that the response to irradiation plus hyperthermia was less age dependent.

Urine volume and excretion of cyclic AMP, cyclic GMP, prostaglandin E{sub 2} (PGE{sub 2}), thromboxane B{sub 2} (TxB{sub 2}) and creatinine were evaluated as potential indicators of radiation damage in mice given 2-5 Gy to the whole body from an enhanced neutron field. In general, urinary cyclic AMP, cyclic GMP, creatinine and urine volumes were positively correlated across time postexposure, for each radiation dose. TxB{sub 2} levels positively correlated with urine volume and cyclic AMP excretion only in animals given 2.0 Gy. None of these parameters suggests their use as a prognostic indicator of the extent of radiation damage. Urinary excretion of PGE{sub 2} was negatively correlated with other urinary parameters. Biphasic increases in urinary PGE{sub 2} were also observed. The initial transient elevation 2-3 days postexposure was not correlated with the dose (2-5 Gy). The second elevation of PGE{sub 2} excretion occurred at 6-10 days. The magnitude of the latter increase suggests that urinary PGE{sub 2} excretion may be a useful indicator of whole-body or kidney exposure to neutron fields.

The dielectric properties of a rat tumour (rhabdomyosarcoma R1H), skin and muscle were measured in vivo with an open-ended coaxial line and a computer-controlled system based on a network analyser. The permittivity of the tumour R1H and of the normal tissues in anaesthetised rats was determined at frequencies between 0.2 and 2.4 GHz. No significant differences were observed either between rat tumour and muscle or between normal and 15 Gy irradiated rat tumour and skin. However, after a hyperthermia treatment at 43{sup 0}C for 60 min the dielectric properties, especially of the rat skin, changed due to the hyperthermic induced oedema which is related to an increase in tissue water content. The process of the oedema modifies the dielectric properties of the skin to a higher degree than those of the tumour.

The radiosensitivity at low partial pressure of oxygen, PO{sub 2} (0-1%) fitted the linear transformation of the Alper, Howard-Flanders relationship giving a K value for mouse lung tissue of 1.35% oxygen with an oxygen enhancement ratio, m, of 2.13. The radiosensitivity at higher PO{sub 2}(5-21%) did not fit the Alper, Howard-Flanders relationship, probably because the PO{sub 2} of the inspired gas was greater than the PO{sub 2} in the alveolus. At the low PO{sub 2} levels in the inspired gas, back diffusion of oxygen from blood into the alveolus may lead to errors in the estimated value of K. If the low value of m is due to this

'contaminating' oxygen from blood, then by taking a higher value for m, the amount of contaminating oxygen can be calculated (0.23%) and a 'true' value for K (1.1%) determined. Other uncertainties in this estimate of K due to the radiolytic consumption of oxygen and possible inadequacies in equilibrium are discussed. Allowing for the uncertainties, it is concluded that the K value for lung damage lies towards the upper end of the range of K values measured for cells in vitro.

In a series of experiments designed to examine the relationships between irradiation and tumour immunity, it has been shown that whole body, low dose irradiation permitted immunization of A/Jax mice with numbers of Sarcoma I (SaI) cells that otherwise elicited either partial tolerance or no detectable immune response. It is suggested that low dose irradiation which inhibits the tumour-associated shifts in T cell subsets, appears to perturb a balanced state of immunity between the effector and suppressor components and permits the anti-tumour effector component to predominate.

X-irradiation of C57BL/6 mice induces thymic lymphosarcomas which sometimes contain retroviruses which upon injection into normal mice mimic the effect of the irradiation. We examined whether specific antigenicities, viral or cellular, were expressed by tumour cells that could be recognized by antibodies from the irradiated animals. We developed monoclonal antibodies (MAbs) using splenocytes of the diseased animal. The reactivity of such MAbs towards thymoma cell lines established in vitro was investigated by means of an ELISA. At least 10 antibody specificities were detected on the 13 tumours investigated, allowing separation of the MAbs into three classes: (i) those recognizing the autologous tumour, heterologous tumours as well as normal thymic tissue, (ii) those specific for the autologous tumour, and (iii) those specific for one tumour, but not ones of autologous origin. The last two classes corresponded to specific tumour-associated antigens. Our panel of MAbs defined each tumour by the particular pattern of antigens harboured. It is striking that most of the antigens were present in the normal thymus and that only two tumours had additional antigenicities. Additionally, quantitative variations were observed in the levels of expression of these antigens.

Hyperthermia increased radiosensitivity with respect to {gamma}-ray induced chromosome loss and breakage in all stages of spermatogenesis in the wild type Oregon R strain of Drosophila melanogaster, whereas hyperthermia increased radiosensitivity to a lesser extent in cn mus(2) 201sup(D1), an excision repair mutant with 0 per cent excision capacity and in mus(3) 308sup(D1), a strain with 24 per cent excision capacity. The differences in hyperthermia-induced radiation sensitivity between the excision repair mutants and the wild strain may be due to the hyperthermia affecting the excision repair mechanism, suggesting that one of the possible mechanisms involved in hyperthermia-increased radiosensitivity is an effect on excision repair.

The effects of X-irradiation on the regeneration of peripheral nerve across a gap were studied in the mouse. The right sciatic nerve was transected and 3 days later a 20-Gy dose of X-rays was administered to the hind limb, which was shielded so that the irradiation affected either the proximal, the distal or both parts of the nerve. The proximal and distal nerve stumps were inserted into a polythene tube within which they were separated by a 5-mm gap. After 1 or 2 months the sciatic nerves were examined by light and electron microscopy. Irradiation affected axonal growth, differentiation of Schwann cells and formation of a perineurium especially when both the proximal and distal stumps had been exposed to X-rays. At 2 months there were fewer axons in the irradiated than in control nerves, but all of the larger axons which had regenerated were myelinated, albeit more thinly than in the controls.

The sensitivity of normal stroma to heat, irradiation and heat combined with irradiation, was studied using the tumour bed effect (TBE) assay. Irradiation before implantation led to a TBE, dose dependent below 15 Gy, but remaining relatively constant above. The interval (0-90 days) between irradiation and tumour implantation did not influence the magnitude of the TBE. Hyperthermia

with large heat doses (45-60 min at 44{sup 0}C) before implantation may lead to a TBE. The interval between hyperthermia and tumour implantation was very important. Results showed that the recovery from heat-induced stromal damage is very rapid. When the interval between hyperthermia and tumour implantation was 10 days or longer, no TBE could be observed. Irradiation combined with large heat doses (30-60 min at 44{sup 0}C) decreased the radiation-induced TBE. The combination of irradiation with mild heat treatments (15 min at 44{sup 0}C) could lead to a larger TBE then after irradiation alone. When hyperthermia was given prior to irradiation, the interval between heat and irradiation proved to be very important. With large intervals (21 days or longer), TBE values were about the same as with irradiation alone. When heat was given after irradiation, irradiation-induced TBE was always reduced.

A homogeneous population of hair follicles in the rat tail has been used to analyse the in vivo response of a biological system to heavy particle irradiation. The conical configuration of the rat tail gives rise to a variable energy degradation of the beam thus yielding information on the damage elicited by the increasing l.e.t. of the helium beam at different sites on the same sample. By means of scanning electron microscopy three different zones were observed as direct evidence of helium ion penetration in the tail. Quantitative evaluation of radiation damage yielded results concerning hair follicle damage after increasing doses for different regions of the ionization curve.

Late damage in the rectum of rats was studied after local irradiation with 2 MeV fast fission neutrons and the results were compared with those for 300 kV X-rays. A similarity between latency times, and between clinical, gross pathological and histological appearances of the rectal obstruction after the two types of radiation was observed. The r.b.e. evaluated from ED 50 200 days values was 1.8 for single doses, 2.1 for two fractions and 3 for five fractions and these are similar to r.b.e.s from other investigations of chronic intestinal radiation damage. Using linear quadratic analysis, a limiting r.b.e. of 5 was obtained. The {beta}values are similar for both radiation qualities. Because of the high {gamma}-contamination (25 per cent) in the RENT I beam a possible correction of the r.b.e. for neutrons only, assuming interaction, is discussed.

An assay for the survival of renal tubule cells was developed using mice, analogous to other in-situ clonogenic cell survival assays. One kidney was irradiated using a {sup 137}Cs irradiator and removed 60-68 weeks later for histological examination. In unirradiated animals there were about 370 tubules in contact with the capsule in a coronal cross section at the middle of the kidney. After irradiation, extensive tubular damage was the dominant lesion. The number of epithelialised tubules in contact with the capsule showed a dose-dependent logarithmic decline. The dose-survival relationship for the clonogenic cells responsible for the regeneration of tubule epithelium was described by a D{sub 0} value of 1.5 Gy over the dose range 11-16 Gy. This radiosensitivity resembles that of stem cells in acutely responding tissues. The lack of histological evidence of damage to the arterial vasculature at the time the tubules are initially denuded of epithelium, and the similarity of renal tubule cell radiosensitivity to that of other mammalian cells, support the hypothesis that ''late'' radiation injury results primarily from depletion of parenchymal cells, not indirectly from injury to blood vessels, as has been the prevailing belief.

Pre-treatment with zinc aspartate protected mice against the lethal effects of radiation and raised the LD{sub 50} from 8 gy to 12.2 Gy. Zinc chloride and zinc sulphate were clearly less active. The radioprotective effect of zinc aspartate was equivalent to cysteamine and slightly inferior to S,2-aminoethylisothiourea (AET). Zinc aspartate displayed a similar therapeutic index to the thiols but could be applied at an earlier time before irradiation. Synergistic effects occurred with the combined administration of zinc aspartate and thiols. By giving zinc aspartate with cysteamine, the LD{sub 50} was increased to 13.25 Gy and, by combining it in the optimal protocol with AET, to 17.3 Gy. The

radioprotection by zinc and its synergism with thiols is explained by the stabilisation of thiols through the formation of zinc complexes.

Experiments were performed to study the protective effect of Wr-2721 (S-2-(3-aminopropylamino)phosphorothioic acid), a derivative of cysteamine and MPG (2-mercaptopropionylglycine) individually on the bone-marrow chromosomes of adult mice when administered before acute whole-body exposures. Taking percentage aberrant cells for 0.5 Gy as the base, the dose reduction factor for MPG was calculated to be 2.6 and that for WR-2721 to be 4.5. (U.K.).

There is a dependence on dose for the duration of the mitotic inhibition which for the more mature cells at the top of the crypt is similar to the widely quoted average value 1 h per Gy, but the duration depends strongly on cell position. Thus not all proliferative cells respond in the same way. The duration is shorter the closer the proliferative cells are to their last cell division in the proliferative hierarchy in the crypt and longest for cells situated where the stem cells are to be expected.

Degenerative processes were studied in pig muscles irradiated with single doses of 30 or 40 Gy. Damaged muscle was gradually replaced by an invasive fibrotic tissue. As a control, surgical muscle exeresis was performed of the same size as the radiation-induced lesions at the same anatomical site. Primary cultures were set up comprising cells freshly extracted from normal dermis, or from tissue exhibiting either normal wound fibrosis or radiation-induced fibrosis. The growth potential of cells taken from the latter region far exceeded that of the two other types; attachment efficiency was higher, and fibronectin was detected early by immunofluorescence. These in vivo and in vitro observations imply that a pathological repair process occurs after localized irradiation.

The effect of actinomycin D (0.4 mg/kg) on radiation-induced lung damage in the mouse was investigated. The drug was administered either 4 weeks before, immediately after, or 16 weeks after single doses of 240 kV X-rays applied to the thorax of CBA mice. Lung damage was assessed by measuring respiration rate, with a whole body plethysmograph. Dose-response curves were obtained at 2-week intervals from 12 to 40 weeks after irradiation. Actinomycin D had no significant effect on respiration rate in this study. A summary of other experimental studies is included which shows conflicting results.

The growth kinetics and the in vivo radiosensitivity of two human small cell carcinomas of the lung (SCCL) grown in nude mice were investigated. The tumours, CPH SCCL 54A and 54B, were derived by in vitro cloning of a single SCCL and were subsequently serially grown in nude mice. The growth curves were described according to a transformed Gompertz function, and the cell kinetics were examined by flow cytometric DNA analysis (FCM) and by the technique of labelled mitoses. The effect of single-dose irradiation was estimated by the specific growth delay calculated from the growth curves, and by the cell cycle distribution changes monitored by FCM. The results showed that the tumors differed in the in vivo radiosensitivity despite similarities in the growth kinetics. The results support the concept that difference in sensitivity among tumor subpopulations is an important reason for therapeutic failures.

The partial tolerance type of 'top-up' experiment has been investigated to determine the resolution of this approach for studying the damage to mouse skin from very small doses of X-rays and neutrons. The effect of 20 fractions, each as small as 0.10 Gy of X-rays or of 0.05 Gy of neutrons, can be detected if 3 MeV neutrons are used as the 'top-up' reference radiation. This capability results from the almost linear underlying dose-response curve and highly reproducible dose-effect relationship for the low energy neutrons. The data fit the linear quadratic model of dose fractionation for X-rays down to fractional doses of 0.75 Gy, but at lower doses there is a trend towards an increase in the skin radiosensitivity. Modelling shows that this might be consistent with a sub-population of the cells showing an exceptional radiosensitivity, and a replenishment of this subpopulation occuring in the 8 h between small dose

fractions. More experiments are needed at very low doses in order to confirm this hypothesis for skin and for other tissues.

The alterations of normal growth of hair follicles following irradiation of rat tails with X-rays have been analysed. The changes in follicle length are attributed to a series of deleterious events occurring in the hair matrix after irradiation. A dose-dependent reduction of length was demonstrated for a given post-irradiation interval. An approximate exponential response was obtained for all conditions excepting low doses for which a marked reduction of follicle length was observed a short time after irradiation was ascribed to the depletion of highly radiosensitive cells. At later post-irradiation times this response was obscured by the resumption of follicle growth.

The effect of dose rate of fast neutrons over a range from 0.02 Gy/min to 22.5 Gy/min on the survival of mouse jejunal crypts was investigated. A small but significant decrease in sensitivity with decrease in dose rate was observed. A 10-fold decrease in dose rate gave a decrease in effectiveness equivalent to 0.39 Gy. The sensitivity to changes in neutron dose rate is much smaller than the sensitivity to changes in dose rate of photons.

CBA/Ca mice were infected by either the intravenous or intraperitoneal route with Mycobacterium microti and the subsequent changes in local macrophage populations examined. Following infection, the number of macrophages increased and they showed greater expression of both MHC Class II molecules. This response was not dependent on viability of the mycobacteria, in contrast to reports with other microorganisms such as Listeria. Studies in sublethally irradiated mice indicated that persistent antigen could give rise to a response after a period of host recovery which was radiation dose dependent. This procedure also highlighted differences in the regulation of different murine class II antigens in vivo, as seen by delayed re-expression of I-E antigens. Macrophage accessory cell function, as assessed by an in vitro T cell proliferation assay, correlated with Ia expression after fixation, but not after indomethacin treatment; this highlights the diverse nature of regulatory molecules produced by these cells.

The effects of X-irradiation on demyelination and remyelination were studied in the peripheral nerve of the mouse. Three days after injection of lysophosphatidyl choline into one sciatic nerve, a 20 Gy dose of X-rays was administered to the hind limb. At survival times ranging from 4 days to 6 months after injection, the nerves were examined by light and electron microscopy. Removal of myelin debris was retarded and remyelination delayed or prevented. The myelin sheaths which did form were thin and the configuration of Schmidt-Lanterman incisures and nodes of Ranvier was abnormal. Some of the chronically demyelinated fibres formed focal node-like complexes; patches of finely granular material coated the inner aspect of the axolemma, the external surface was covered by slender processes of Schwann cell cytoplasm, and an electron-dense lamina was present in the enlarged periaxonal space. Elsewhere demyelinated axons and their ensheathing Schwann cells were separated by gap junctions or transverse bands. These findings indicate that the morphological differentiation of structures thought to be characteristic of nodes of Ranvier can take place in the absence of remyelination.

The mouse coat and eye colour mutant beige (bg) leads to the production of distinctive retinal melanocytes with abnormally large pigment granules. Heterozygotes for bg were given 2 Gy acute X-irradiation at various times between day 11.5 of fetal life and 3 days after birth, at which age whole mounts were prepared of the retinal pigmented epithelium (RPE). These were scanned for the presence of mutant retinal melanocytes with large granules, either as single cells or as clones. The earlier the fetal irradiation, the greater was the effect on RPE area at 3 days post-partum (p.p.), which fell to about half normal with the 11.5-day fetal exposures. In the present experiment, numbers of mutant melanocytes per clone tended to decrease with later irradiation, but not to the extent expected from the greatly increased numbers of cells at risk over the same period. It was concluded that the bg test system showed great promise for

the study of in vivo mutagenesis in somatic cells, especially as the fetal RPE is pigmented from 11.5 days p.c. in the mouse.

Radiation effects are mediated in part by the generation of oxygen-derived free radicals and hydrogen peroxide. Membrane polyunsaturated fatty acids are important biological targets of these toxic molecules which cause lipid peroxidation. Radiation damage to DNA is also known to result in base hydroperoxides, especially thymidine hydroperoxide. Glutathione (GSH) is known to inhibit lipid peroxidation both chemically and through its interaction with the selenium-dependent glutathione peroxidase (GSH-Px). Although cytosolic GSH-Px can metabolize organic lipid peroxides in solution, it cannot metabolize phospholipid peroxides in micelles. This may be due to the interference of phase differences between the aqueous cytosol and the membrane, or the result of steric hindrance. Recent studies have suggested the presence of a membrane-bound GSH-dependent peroxidase system. The authors examined the cytosolic versus membrane-associated GSH-Px, in various tissues of mice on a selenium and vitamin E deficient diet, and found significant differences among organs in the distribution of enzyme activity in these two subcellular fractions. The effect of single high-dose whole body irradiation did not appear to be related to the activity of these enzymes.

The effects of bendazac-L-lysine salt on some biochemical parameters (soluble and insoluble proteins, reduced glutathione, sulphydryl and disulphide groups, water content) in rabbit lens at different times after X-rays (2000 rads) were studied. In the mature cataract which developed 11-12 weeks after irradiation, the irradiated lenses not treated with bendazac-lysine (ILNTB) show a 32% increase in water content compared with controls; this increase is 12% in irradiated lens treated with bendazac-lysine (ILTB). Twelve weeks after irradiation the concentration of insoluble proteins in the controls, ILNTB and ILTB is 7.6%, 52.3% and 18.3% respectively. After 6, 8 and 12 weeks the concentration of reduced gluthathione in ILNTB decreases by 23%, 81% and 92% as compared with the controls. In the ILTB the decrease is present only 8 and 12 weeks after X-irradiation and is of 55% and 69% respectively. The sulphydryl-group content in the soluble proteins in ILNTB compared with the controls decreases by 26%, 38% and 47% after 6, 8 and 12 weeks, while in the ILTB a decrease is observed only after 8 and 12 weeks and is 6% and 12% respectively. The decrease of the sulphydryl groups parallels the increase of the disulphide groups. This increase is already significant (P < 0.01) after 6 weeks in the ILNTB, whereas it becomes significant in the ILTB only after 8 weeks. The chromatogram of the soluble proteins shows that the high-molecular-weight protein content (HMW) is 5.5% and 12.6% in the ILTB and 8.8% and 27.4% in the ILNTB after 8 and 12 weeks, respectively. In the control lenses the HMW was about 1.2%. The HMW content in the ILNTB after 6 weeks is higher as compared with controls and with the ILTB. A slight increase of the {alpha}-crystallin fraction and a decrease of {beta}and {gamma}-crystallin fractions.

In the present study, both autoradiography and three-dimensional serial reconstruction were used to monitor fiber cell differentiation and changes in lens cell volume and morphology throughout radiation cataract formation. Lenses of 4-week-old rats developed subtle (0.5+ to 1.5+) cataractous changes at 15 weeks after X-irradiation with 400 rad. At this time, these lenses were not significantly altered in lens cell volume and did not show prominent changes in lens cell morphology. A different situation was obtained for rat lenses exposed to 1200 rad. By 3 weeks after X-irradiation, these rat lenses showed significant changes in both cortical fiber morphology and cell volume. These alterations happened prior to when cataractous changes were previously found to occur in these animals (Merriam and Szechter, 1975). At 15 weeks, when moderate cataracts (2.0+ to 3.0+) formed in these lenses, cortical fiber morphology was disrupted, while fiber cell volume was similar to unirradiated controls. Eventually rat lenses irradiated with 1200 rad developed severe (4+) cataracts 32 weeks after exposure. The authors claim this is the first report of cortical fibers increasing transiently in volume prior to cataract formation.

The authors studied the effect of combined therapy with X-ray and 1-{beta}D-arabinofuranosylcytosine (Ara-C); firstly the effect of whole-body X-irradiation alone on the proliferation of the L1210 ascites tumour of the mouse was studied by autoradiographic and cytofluorometric (FCM) methods. The effect of X-irradiation with 4 Gy was mainly a cytostatic one leading to an altered distribution of the cells throughout the cycle due to radiation induced mitotic delay. The cytocidal effect is negligible. As is known from previous studies (Fietkau, Friede and Maurer-Schultze, 1984) the effect of 200 mg/kg Ara-C consists of an inhibition of DNA synthesis and of killing a considerable portion of the L 1210 cells, predominantly of S phase cells. No significant differences between the various combined therapies were found. Whole-body X-irradiation with 4 Gy followed by the application of 200 mg/kg Ara-C 10 hr later resulted in the greatest increase of the mean survival time of tumour-bearing animals, from 13.2 to 17.4 days. It was shown that apart from the cytocidal effect on S-phase cells, Ara-C also kills cells sublethally damaged by a preceding X-irradiation.

A machine for decommissioning nuclear reactors comprises a shield structure to be mounted rotatably at the open top of the reactor pressure vessel, a mast mounted on the shield for extension through an opening in the shield and a tool-carrying manipulator mounted on the mast. A slew beam provided with a hoist is provided beneath the shield for handling dismantled material created by operation of the manipulator. The shield opening can be closed by a number of slidable shield sections and the opening can be increased in cross-section to allow the manipulator when retracted, to be drawn upwardly through the shield into a decommissioning module in which the manipulator can be extended to permit tool changes to be made.

This paper describes practical experiences in dealing with non-linearities in temperature field calculations. First the use of the load vector for representing the heat radiation on the outer surfaces is reported. However, if there are also additional non-linearities in the conductance matrix, then it may happen that because of possible counteractions of the non-linearities no convergence is achieved, at least with the direct iteration. Therefore it is more appropriate to put the radiation terms into the conductance matrix where the other non-linearities, such as temperature dependent thermal conductivity and natural convection also appear. It is shown how the Newton-Raphson iteration can be applied in an easy way. In the case of temperature dependent heat sources the load vector also needs to be considered. The appropriate special measures are described.

Following two incidents at Hinkley-A and Hinkley-B in 1984 and 1985 the standard of maintenance at this power station is questioned. In early 1987 three out of four of the Hinkley reactors were shutdown -the Hinkley-B shutdown being caused by a blocked valve, Hinkley-A by corrosion. Pockets of leukaemia have been found in villages close to Hinkley Point - figures are quoted. The adequacy of monitoring in the vicinity is queried, especially immediately following the Chernobyl accident. The attitude of the relevant local authorities to calls for independent radiation monitoring of the environment is mentioned. Several counties may agree on a joint monitoring scheme. (U.K.).

The paper concerns the dismantling of the Windscale advanced-gas-cooled reactor, United Kingdom, which has been under way for nearly five years. The dismantling includes dealing with high levels of radioactivity from contaminated and activated materials. The stages of decommissioning are described, along with some of the problems encountered and robotic equipment for dismantling the reactor core. Disposal of the decommissioned radioactive waste from Windscale, and from the Magnox stations due for decommissioning, are also discussed. (U.K.).

The Windscale prototype reactor is being decommissioned and dismantled. The stages are outlined. The first phase began in 1985 and included construction of a waste packaging plant annexed to the steel dome. The boilers will be cut up and, once decontaminated, probably sold for scrap. The second phase involves dismantling the reactor itself. Much of this will be done by a semi-automatic

robot which is being specially built and tested. The robot will have an extendable arm with a manipulator which will be equipped with bolt croppers, shears, a saw and oxypropane cutter. This robot will cut up the pressure vessel in sections ready for encasing in concrete. Lessons learnt from the dismantling will be used in future reactor designs and specifications (eg the need to use steels with fewer impurities, especially cobalt). Ultimate disposal of the concrete waste blocks is undecided. (U.K.).

Each of the helically coiled pod boiler units has 285 tubes in which feedwater at 157 {sup 0}C is heated to superheated steam at 543 {sup 0}C and 169 bar. A ferrule is fitted at the inlet to each tube to provide a stabilizing pressure drop which can be varied to adjust the feed flow to match the variations in heat duty for different rows of tubing. The original design of ferrule was welded to the tube and tubeplate, so ferrule replacement required the development of techniques to machine out the old ferrules and to attach replacements. This Paper explains why ferrule replacement was considered to be necessary, describes the development of replacement techniques and reviews the success of the exercise to replace ferrules in reactor 1 at Heysham. The effects on boiler performance of installing new ferrules are also described.

An incident at Hunterston A number one Magnox reactor in May 1986, when a fuel assembly became jammed in a fuel channel, has given rise to concern about the safety, not only of Hunterston A, but at all the UK Magnox stations, most of which have already operated beyond their 20 year design life. Although the incident cited was during a planned shutdown and there was no release of radioactivity, other incidents are mentioned as evidence that the Magnox reactors should be closed immediately. The safety reports of the Magnox stations have not been published, giving rise to further doubts about their safety.

It is argued that there is no need, based on demand, for the Torness AGR station to be commissioned. The costs of going ahead with the operation of the reactor are compared with the cost of mothballing the plant. The costs considered include the effect on the Scottish mining industry and the problem of dealing with the radioactive wastes it will generate. However, both options will cost money. Continuing will increase the cost of electricity by about 35%. Mothballing will also increase the costs.

The paper reviews the thirty years of operation of Calder Hall, the world's first commercial nuclear power station. The history of the construction of the power station is briefly given. The operational history of Calder Hall is described with respect to: plant performance, operational reliability, introduction of technical improvements, and plant safety. The major milestones in the station's 30 years of operation are listed chronologically. Present day operation and maintenance of the station is also reviewed. (U.K.).

The paper reviews some of the highlights of metallurgical experience with Calder Hall fuel, which laid the foundations for the British Magnox reactor system. A description is given of the first Calder Hall fuel elements, along with the initial experience with these elements with respect to: bowing, 'fast' bursts, and 'slow' failures. Monitoring the performance of the fuel led to more information on the physical properties of the irradiated materials in fuel elements. The use of Calder Hall reactor to test prototype designs and potentially promising materials for fuel elements, is also described. (U.K.).

The paper reviews the thirty years of operation at Calder Hall, 1956-1986, with emphasis on the significant changes that have occurred in plant operation and operational procedures within that time. The topics discussed include: heat and power production, gas circulator drive system, feed water control, demineralised water supplies, primary coolant (CO{sub 2}) supplies, and electrical supplies. (U.K.).

The engineering achievements at Calder Hall, 1956-1986, are reviewed with respect to the maintenance, inspection and problems of the major items of plant at the station. The plant items considered include: the pressure vessel, heat

exchangers and ducts, main blowers, turbo alternators, CW systems, electrical systems, instrumentation, primary coolant (CO{sub 2}) supply system, feedwater supply system, steam system, fuel route, cranes, and steelwork structures. (U.K.).

The paper looks at water chemistry and Calder Hall nuclear power station plant, United Kingdom. A description is given of the water chemistry system, the ion-exchange (water treatment) plant, and the chemical conditioning of the water system at the station. The deaeration of the feedwater is briefly explained. Heat exchanger tube problems include economiser tube failures and evaporator tube failures, which are both discussed. Finally, an outline is given of the water condition monitoring programme. (U.K.).

The paper examines the role of in-service inspection in the validation of integrity of the Calder Hall and Chapelcross reactor pressure circuits. The inspection techniques and equipment are described for the reactor pressure vessel, primary circuit duct, and heat exchanger, together with a summary of recent findings. Inspection of the reactor pressure vessel is carried out by: high resolution photography, remote ultrasonics, manipulators, and closed circuit television. Primary circuit duct inspections are visual surveys and, where necessary, surface crack detection examination. Heat exchanger inspections are visual inspections. (U.K.).

The pebble bed high temperature reactor (HTR) is one of the most important German innovations in the field of reactor technology. Detailed design of a 550MWe plant - HTR 500 - is now under way. This builds on construction experience with THTR 300, a 300MWe high temperature reactor, which started electricity generation in November 1985. THTR 30 is the reference plant for a range of high temperature reactors now under development, including a 100MWe modular unit.

The graphite sleeves of a fuel stringer of a gas cooled nuclear reactor are formed with a rib/groove profile on their external surfaces in order to increase the resistance of flow through an annular passage between the stringer and the seal bore of a channel during raising or lowering of the fuel stringer from or into the reactor core. The ribbing may extend around or along the sleeve or may extend helically about each sleeve in multi-start fashion and may have an asymmetric profile so that the resistance to coolant flow is less when the stringer is in situ in the reactor core than when the stringer is being raised or lowered.

A detailed emergency plan for the reactor is presented. Definitions, conditions for taking action, duties of staff, emergency control centres and equipment, communications, both internal and external, hazard assessment, including iodine inhalation and radioactive deposition procedures, collaboration with other bodies, warnings to the public and exercises are among topics described.

A detailed emergency plan for the reactor is presented. Definitions, conditions for taking action, duties of staff, emergency control centres and equipment, communications, both internal and external, hazard assessment, including iodine inhalation and radioactive deposition procedures collaboration with other bodies, warnings to the public and exercises are among topics described.

A detailed emergency plan for the reactor is presented. Definitions, conditions for taking action, duties of staff, emergency control centres and equipment, communications, both internal and external, hazard assessment, including iodine inhalation and radioactive deposition procedures collaboration with other bodies, warnings to the public and exercises are among topics described.

A detailed emergency plan for the reactor is presented. Definitions, conditions for taking action, duties of staff, emergency control centres and equipment, communications, both internal and external, hazard assessment, including iodine inhalation and radioactive deposition procedures, collaboration with other bodies, warnings to the public and exercises are among topics described.

A detailed emergency plan for the reactor is presented. Definitions, conditions for taking action, duties of staff, emergency control centres and equipment, communications, both internal and external, hazard assessment, including iodine inhalation and radioactive deposition procedures, collaboration with other bodies, warnings to the public and exercises are among topics described.

A detailed emergency plan for the reactor is presented. Definitions, conditions for taking action, duties of staff, emergency control centres and equipment, communications, both internal and external, hazard assessment, including iodine inhalation and radioactive deposition procedures, collaboration with other bodies, warnings to the public and exercises are among topics described.

A detailed emergency plan for the reactor is presented. Definitions, conditions for taking action, duties of staff, emergency control centres and equipment, communications, both internal and external, hazard assessment, including iodine inhalation and radioactive deposition procedures, collaboration with other bodies, warnings to the public and exercises are among topics described.

A detailed emergency plan for the reactor is presented. Definitions, conditions for taking action, duties of staff, emergency control centres and equipment, communications, both internal and external, hazard assessment, including iodine inhalation and radioactive deposition procedures, collaboration with other bodies, warnings to the public and exercises are among topics described.

A detailed emergency plan for the reactor is presented. Definitions, conditions for taking action, duties of staff, emergency control centres and equipment, communications, both internal and external, hazard assessment, including iodine inhalation and radioactive deposition procedures, collaboration with other bodies, warnings to the public and exercises are among topics described.

A detailed emergency plan for the reactor is presented. Definitions, conditions for taking action, duties of staff, emergency control centres and equipment, communications, both internal and external, hazard assessment, including iodine inhalation and radioactive deposition procedures, collaboration with other bodies, warnings to the public and exercises are among topics described.

A moderator heat recovery scheme is proposed for CANDU reactors. The proposed circuit utilizes all the moderator heat to the first stages of the plant feedwater heating system. CANDU-600 reactors are considered with moderator heat load varying from 120 to 160 MWsub(th), and moderator outlet temperature (from calandria) varying from 80 to 100{sup 0}C. The steam saved from the turbine extraction system was found to produce an additional electric power ranging from 5 to 11 MW. This additional power represents a 0.7-1.7% increase in the plant electric output power and a 0.2-0.7% increase in the plant thermal efficiency. The outstanding features and advantages of the proposed scheme are presented.

The paper concerns the fast reactor fuel facility, known as FACET (facility for enhanced throughput of fuels and pins), to be built at the UKAEA's Windscale Nuclear Laboratory. The facility is designed to improve the service available in experimental fuel manufacture, in connection with fast reactor work. A description of FACET is given, along with the operation of the facility.

The development of a reliable steam generator for the fast breeder reactor is discussed. An account of experience with the DFR boilers and PFR steam circuits is given. Current design concepts are outlined, together with design issues. The preferred choice of design in the UK, a straight tube boiler with J-tube geometry, is described.

The patent reports on nuclear reactor fuel assemblies which can be used in liquid metal cooled fast reactors. The invention relates to multi-pin fuel assemblies with the pins contained within a hexagonal tubular wrapper and supported or stabilised by spaced grids. The grids are supported by inward projections from the wrapper which trap the grids without penetrating the grids. (U.K.).

An inspection system for detecting leakage from for example the primary vessel of a nuclear reactor includes a camera carried by an umbilical cable which can be fed through a duct assembly comprising a series of tubular sections connected endwise by flexible bellow. A guide track extends around the top of the vessel and each duct section is provided with wheels which engage the track. A curved guide tube feeds the duct sections from a vertical entry position in the roof into a horizontal track-engaging disposition. The track includes spaced flanges through which the umbilical cable can extend and depend downwardly into the annular space between the primary vessel and a surrounding guard vessel.

This paper reports the results of a static stress analysis in piping elbows, either with or without stiffening effects due to the sectional ovalization restraint provided by tangent straight pipes. The physical and geometrical aspects together with the loading conditions used in this study are typical of those of pipings for main cooling systems of Liquid Metal Fast Breeder Reactors (LMFBR). The aim of the study is directed towards comparing stress intensification factors in elbows subjected to pure in-plane bending moments obtained by experimental, analytical (using the ASME Section III Subsection NB3685 detailed analysis procedures) and numerical tests. The numerical calculation was performed taking into account some non-linearity effects due to the particular geometry of sections or load-induced phenomena, and neglecting the plastic response of the material (elastic behaviour).

Electric utilities are characterized as timid risk averters that select coal or nuclear plants or both, where the levellized cost of each is characterized by considerable risk. A portfolio selection model is developed to explain the historical demand for nuclear reactors by region. Some qualitative policy implications are derived with respect to the DOE's objective of reviving the nuclear power market.

In this debate the Government's policy on nuclear power is discussed. Government policy is that nuclear power is the safest and cleanest way of generating electricity and is cheap. Other political parties who do not endorse a nuclear energy policy are considered not to be acting in the people's best interests. The debate ranged over the risks from nuclear power, the UK safety record, safety regulations, and the environmental effects of nuclear power. The Torness nuclear power plant was mentioned specifically. The energy policy of the opposition parties is strongly criticised. The debate lasted just over an hour and is reported verbatim.

The French nuclear power programme is considered by its supporters to be efficient and cost-effective. However, the building programme has been possible only by borrowing money so that France now has a huge national debt. The programme has been able to proceed partly due to lack of available channels of effective opposition. The capital costs have been minimised by using a standard design. However, this standardisation has had three adverse consequences, overcapacity, industrial inflexibility and generic faults. Each is considered in turn, and the safety record examined by looking at specific incidents. France's nuclear weapons programme is seen as closely linked with the civil nuclear programme, hence the building of Superphenix, a fast reactor which produces plutonium. Overall the French nuclear programme is described as potentially disastrous. A map showing nuclear establishments in France is given.

A comparison of electricity generation costs in different countries is presented. The difficulties in carrying out such a comparison are outlined, as well as the different approaches to determine the costs. Factors contributing to the variations in capital costs between countries are discussed, along with fuel costs. The overall levellised generation costs, including all stages of the fuel cycle and all investment and long term plant costs, for different countries, are given in tabular form. The table shows that nuclear energy has a considerable advantage over energy derived from coal in all countries except the USA. (U.K.).

This report has been produced as a contribution to the continuing debate on the relative economics of coal and nuclear for power generation. The starting point

for the analysis is a recently published report by the OECD Nuclear Energy Agency (NEA) produced by an expert group set up to examine the projected costs of power generation. After setting out the objectives and explaining the framework of the report the NEA methodology is compared for examining the relative economics for coal-nuclear electricity generation costs. Results obtained are compared with those of NEA. Sensitivity tests are performed. Other parameters e.g. plant lifetimes are also considered. The conclusions are presented in Chapter 6. The results show that there is sufficient uncertainty in the figures to indicate that the nuclear-is-cheaper-than-coal argument can no longer be used in decision making by utilities and the government. (U.K.).

Three factors have emerged in recent months to create doubts over Sweden's present energy situation and its prospects for the future. The 'Chernobyl effect' has reinforced anti-nuclear sentiment and prompted a study by Energy Council experts on the possibility of phasing out nuclear power ahead of the 2010 deadline set in the 1980 referendum. Secondly, the fall in world oil prices to half the previous levels has pointed to a possible halt in the long-term decline in oil use which has been a feature of the Swedish energy scene for the past fifteen years, more especially since 1980. Thirdly, the start-up last year of natural gas imports from Denmark could soon be followed by a very much bigger deal with either Norway or Finland, while the deep gas project in progress at Gravberg offers the hope of discovering indigenous supplies. Either way, a major switch to natural gas could ease the transition in the electricity sector away from nuclear generation.

The motion debated was that the House takes note of the Report of the European Communities Committee on Nuclear Power in Europe. This led to a debate lasting nearly six hours with 26 speakers which is reported verbatim. The motion was agreed. The report is widely praised. The debate ranged over the effects of the Chernobyl reactor accident, when Lord Marshall of Goring explained that such an accident could not happen in the UK, to the economic, ecological, employment, and other consequences of a nuclear power programme. Renewable energy sources, safety in the nuclear industry, international cooperation (particularly in safety), the proposed Sizewell-B reactor, radioactive waste disposal and public education are also mentioned. (U.K.).

The nuclear power programmes in developing countries, following the accident at the Chernobyl power plant are summarized. Many of these have abandoned plans for nuclear power (eg Gabon), mothballed existing reactors (eg Philippines) or deferred decisions on a reactor programme (eg Egypt, Taiwan, Libya). Economic and political pressures are usually the underlying reasons, but the Chernobyl incident has proved a useful excuse. Other countries (Nigeria, Korea, India, Pakistan) have not let the accident change their nuclear policy. In China, Israel and Turkey the debate about nuclear power has been sharpened by the accident. Although Chernobyl has hastened decisions on nuclear power in some countries it has not affected the long-term policies of developing countries.

The cost effectiveness of the Magnox reactors is challenged. Tabulated data show that both Magnox and AGR reactors are nearly 10% more expensive to run than coal-fired stations. The costs are considered in some detail. The situation for AGRs in general is considered first, then for the Torness reactor in Scotland. The economic arguments presented on behalf of PWR type reactors are also questioned as well as the more fundamental questions of whether the electricity demand justifies more nuclear power plants being built. The economics of nuclear power in the USA and France is also considered.

The latest Soviet five year plan seems to confirm that, with its new construction heavily dependent on PWRs, the country's nuclear programme will forge ahead despite Chernobyl.

This is a revised and updated edition of 'Nuclear Fuel and Power, Capacity, Demand and Trade Prospects', first published in March 1984. It presents the results of an analysis of projections of effective nuclear power generating capacity in all countries during the remainder of this century, projections of

nuclear power production, its fuel requirements and its relation to electricity demand in OECD countries during the same term and projections of indigenous and imported natural uranium supply in OECD countries up to 1995. The results are summarized in Part I. Detailed results and projections for OECD countries, the Third World and the CMEA (Europe) countries (the Soviet Union and the six East European members of the CMEA), are discussed in Parts II,III and IV. The methods are explained and results tabulated in the Appendices. It was published in April 1986 before the accident at the Chernobyl reactor.

Europe's electricity industry is entering a period of extreme uncertainty. This report sets out the reasons for this and tabulates the current electricity capacity in Europe. Chapter 2 considers the Electricity trade in Europe. Chapter 3 concentrates on nuclear power. In this, nuclear energy consumption in 1974 -1984, estimates of total and nuclear electricity generation to 2000, the European nuclear reactor types and the performance of reactors are tabulated. Nuclear power stations under construction are listed. A forecast is made of European nuclear capacity to 2000. The status of nuclear power in 1986 in Europe is summarized country by country. The future of nuclear power in Europe, following the Chernobyl reactor accident is considered, taking the situation in each country separately. Chapter 4 considers Electricity and the Environment, Chapter 5 looks at the prices of electricity in Europe, Chapter 6 is a country by country profile which presents the present and predicted electricity power situation in that country.

Following the accident at the Chernobyl reactor in April 1986, the 1986 Annual Delegate Conference of the Institution of Professional Civil Servants set up a Working Party to review the Institution's energy policy, including safety and environmental factors. The review is presented in two volumes as the basis for discussion by the members. Volume I is the main report. Section A, the introduction, includes a summary of the detailed conclusions and recommendations of the Working Party. Section B (chapters 4-12) concerns all aspects of nuclear power including fuel reprocessing and waste management. Section C (chapters 13-16) considers the alternatives to nuclear power and Section D (chapters 17-24) looks at the economic and social aspects of energy policy. The appendices, which contain the detailed technical and source information used by the Working Party in reaching its conclusions, are printed separately in Volume II.

The public inquiry into the Central Electricity Generating Board's application to build the first PWR reactor in the United Kingdom (at Sizewell) ranged beyond that particular issue to a more general investigation of the desirability of promoting nuclear power generally. The CEGB's case is presented briefly. The four main arguments are security of electricity supply, diversity of supply, the benefits of PWRs as opposed to AGRs and cost savings. This latter was important to justify not only the need case, but the economic case for Sizewell-B. The economic case included five computed scenarios over a range of the proposed station's capital, fuel and related operating costs, set against three 'no-nuclear', 'medium nuclear' or 'high nuclear' backgrounds. The CEGB figures are compared with those from objectors. The main arguments are outlined. Other political and technical arguments were not examined in depth by the Inquiry.

The book on ''Future stresses for energy resources'' concerns the long-term comparison of world energy consumption measured against resources in regions, up to the year 2060. An evaluation is carried out on the nature of the stresses which may result in various regions and in different energy sectors from a lack of indigenous resources. (U.K.).

Ion cyclotron heating on TEXTOR has now reached the Megajoule level. The heating scenario is normally mode conversion but occasionally minority heating in a D-(H) plasma. With appropriate wall conditioning by carbonization more than 1 MW of RF power has been injected for long pulse durations (approx. 1 s). The ICRF heated plasma is characterized by a quasi-stationarity of all plasma parameters, little or no impurity increase and a loop voltage reduction resulting in the total power coupled to the plasma reaching six times the remaining ohmic power input. Evidence of the coupling of the RF power to the plasma is obtained from

the increase of the thermal load on the limiters and central energy deposition is supported from analysis of the sawtooth heating rate. The energy deposition profile appears to be broader than in the OH case. A detailed study of the global energy confinement time shows a degradation with additional RF heating which is found to scale with the power and the plasma parameters as in the case of neutral beam heating experiments performed in the L-mode regime with gettered walls.

Fast relaxations of the electron temperature profile during pellet injection or disruptions, and its readjustment during additional heating are described. A global picture for both phenomena is proposed.

The latest analysis of results from the Bundle Divertor and prospects for application to a tokamak reactor are presented. The upgraded version of the machine, DITE IB is described briefly. Initial results of a programme to study the causes of disruption at high density in ohmic and beam-heated discharges are also described.

JET results are presented which show a ''profile consistency'' of the electron temperature under a variety of plasma conditions. This experimental fact is interpreted as due to a topology of the magnetic field lines where ordered structures such as laminar surfaces and magnetic islands coexist with ergodic domains. The development of this concept identifies different plasma regions according to the value of the safety factor and relates the observed degradation in confinement time, when Additional Heating is applied, to the plasma entering a multiphase state where the electron temperature gradient is limited by a critical value defined by the global plasma parameters. A preliminary scaling law for the electron temperature is proposed which indicates a strong favourable dependence on major radius and plasma current. Losses due to atomic processes at the plasma edge give rise to thermal instabilities with low m numbers, which induce ergodic regions. Plasma disruptions could be considered as the effect of these very low number instabilities (m=2,3). The near future JET experimental programme is briefly described and possible ways of improving the plasma confinement are presented.

Electron Cyclotron Resonance Heating, (ECRH), provides an opportunity of adding a local power contribution to the electron plasma component. Thus, the electron temperature profile can be varied at will and the dependence of electron heat losses on the shape of the profile can be studied.

Recent developments in the theory of MHD waves in connection with radio-frequency heating in the Alfven Wave and Ion Cyclotron Ranges of Frequencies (AWRF, ICRF) are reviewed. The account is personal and focusses on the discussion of full wave solutions and the oscillation spectra in bounded, generally inhomogeneous, plasmas. Original results are presented concerning forced ICRF oscillations in a current-carrying torus. The effects on the wave structures of the equilibrium current, the size of the device, the minority concentration and the phenomenological damping are investigated. The resonant surfaces coincide with the magnetic surfaces as in the AWRF. The poloidal extension of the resonance is small in cases where a WKB approach is permitted so that there is no conflict between full wave solutions and the WKB method.

Due to the interaction of plasma with in-vessel components, serious erosion is experienced in present machines. A summary of basic processes, model experiments concerning them and their relevance to the real physical situation is reviewed. The newest trends in methods to minimize erosion and plasma contamination such as divertors, gettering and discharge cleaning techniques are also summarized.

The generation of ultra high pressure by laser beams is reviewed in the context of laser driven inertial confinement fusion. Central pressures of 200GBar are required in an imploded pellet and are achieved by the amplification of the laser generated pressure in the implosion. The theory of laser driven ablation predicts greater efficiency with shorter laser wavelength but with the penalty of greater susceptibility to laser beam non-uniformity. A variety of

experimental measurements of laser ablation are described and their results are in good agreement with applicable theories. Factors determining the overall implosion symmetry and pressure multiplication are discussed briefly.

Initial ohmic heating experiments in JT-60 were performed for a three month period. A maximum plasma current of 1.6 MA was obtained for both divertor and limiter discharges. Low-q discharges of qsub(eff) = 2.5 and high density discharges of 4.8 x 10{sup 19} m{sup -3} in line-averaged density were obtained in the divertor configuration. In divertor discharges radiated loss from the main plasma can be kept at 20 - 30 % of the ohmic input.

RF power up to 450 kW has been injected into the plasma of FT in the electron heating regime (n-barsub(e) <= 5 x 10{sup 13} cm{sup -3}) producing electron and ion temperature increases of about 1 keV and .5 keV respectively without significant enhancement of Zsub(eff). A density increase is observed due to an improvement of particle confinement time. An energy balance at intermediate power level (Psub(RF) = 300 kW) is carried out for two different types of discharges, one without sawteeth the other with sawteeth. The balance shows that in order to account for the total injected power one has to assume equal electron thermal conductivity for the OH and the OH+RF phase. The energy confinement time does not vary from its ohmic value for both discharges. Finally an investigation, at n-barsub(e) above the density limit, of the radial source of the fast ion tails and of the characteristics of the Parametric Decay Instability is presented.

The basic physical problems determining the fusion prospects of the open traps are considered. Main attention is paid to the possibility of a scalable modelling of the anomalous transverse transport in long solenoids (which are a necessary component of most of the types of open traps), and to the problem of the MHD stability of axisymmetric ambipolar traps. The experimental device for studying the transverse transport in a long solenoid, based on the concept of a gas-dynamic trap, is described. Various axisymmetric MHD - stabilizers for ambipolar traps are considered, including the recently suggested stabilizer in the form of a ''fat'' mirror machine. Such a stabilizer is shown to provide the suppression of large-scale flute perturbations in the framework of a ''natural'' geometry of open traps.

The present status of ICF with lasers and ion beams is reviewed and the basic physics related to it is exposed (beam absorption, pressure generation, symmetry and stability). Trends and near future developments are discussed.

Studies of ion confinement in Doublet III show that the ion thermal diffusivity chisub(i) exceeds the neoclassical value by a factor of two to four at r = 0.2a increasing to a factor of ten at r = 0.7a. It appears that chisub(e) and chisub(i) are always closely equal, suggesting turbulence underlies the diffusion. Scaling data for energy confinement time dependence on heating power, density, current, and toroidal field are reviewed to constrain the formulation of a transport model based on turbulence. A model based on trapped electron turbulence is proposed which produces the correct scaling behavior of tausub(E) in both low and high collisionality regimes.

First ICRF experiments on ASDEX have been performed at 67 MHz, corresponding to 2{Omega}ub(CH)-heating of a hydrogen plasma at B{sub 0} = 2.2T. Despite divertor operation ICRH is accompanied by a significant increase of impurity production which can drastically be reduced by means of wall carbonisation. RF power up to 2.3 MW is routinely coupled to the plasma for pulse lengths of up to 1 sec. The rf heating is found to depend strongly on plasma preheating. In combination with neutral beam injection the ICRF heating efficiency is even higher than the one of NI. Confinement degrades with ICRH to values in between NI-L-type and OH confinement.

Recent results from the new 12-beam compression facility at Rutherford Appleton Laboratory are discussed and novel experiments are described which use

thermonuclear particle spectroscopy to measure compression uniformity, fast particle dE/dx and hydro instabilities.

The present model of sawtooth oscillations does not appear to be consistent with experimental observations on JET. Al alternative theory is proposed, offering possible explanations for the basic aspects of the observed behaviour.

In 1986 the problems associated with the implementation of nuclear power programmes mainly arise from difficulties of social acceptability. The scientific and technological achievements are no longer a source of wonder and are taken for granted by a public which has become accustomed to such achievements in other fields. This lecture recounts the history of the nuclear fuel cycle starting around 1955 but continuing, to look at future prospects. The problems are discussed. The technical improvements that have occurred over the years mean that, currently it is possible for all the problems to be overcome technically. Although there is always room for improvements in endurance, design etc. commercial and safety requirements can be met. In economic terms, the real costs of the fuel cycle have reached a plateau and should decrease as the result of lower cost for enriched uranium, lower reprocessing costs and better fuel management. However, in social and political terms, the position is not so certain because of public concern about reprocessing plants and the disposal of radioactive wastes. (U.K.).

When the body is exposed to low penetrating radiation such as beta or low energy X-rays, the skin, eyes and sometimes testes may be the most highly irradiated organs of the body. In order to assess the biological response following such exposures it is necessary to understand the radiobiology of the specific organs and, in particular, the identity and depth of the most radiosensitive cells. This information is also directly relevant to the needs of those responsible for calculating and measuring doses to personnel. Up to date information on the identification and depth of cells at risk, and the biological response following non-uniform exposures will be reviewed. The limitations in this knowledge which are creating problems for dosimetric applications are identified so that radiobiology programmes can then be evaluated and tailored to meet these practical needs.

Concern over beta particle dosimetry in the United States led to a number of workshops and symposia at which the National Council on Radiation Protection and Measurements (NCRP) was encouraged to review its recommendations about beta particles. The NCRP responded by forming Scientific Committee No. 80 on Radiobiology of the Skin to start the review. It was directed to prepare recommendations concerning: (1) the depth(s) in the skin at which dose measurements shall be made, (2) the range of depths over which the dose can be averaged, (3) the area of the skin over which the dose can be averaged, and (4) what measurements are required in protecting the whole skin. The recommendations are to apply to all radiations, not just to beta particles. How the measurements are to be made will be left to a later committee. The committee is not required to recommend permissible doses for the skin. The committee has met five times so far to examine the information available on the stochastic and non-stochastic responses of the skin to both ionising and non-ionising radiations.

Two surveys were performed, in 1983 and 1985, on behalf of EURADOS, the European Radiation Dosimetry Group, with the objective of obtaining information on beta particle exposure of radiation workers. The underlying idea was to assess the need for, and explore possible future activities of, a subcommittee in the field of beta radiation dosimetry. For this purpose two questionnaires were sent out. They were addressed, firstly, to personnel monitoring services in order to identify users with potential beta exposures and, secondly, directly to those users, in order to acquire more details on the subject. The replies of 16 personnel monitoring services and some 45 nuclear facilities, hospitals, industrial and research laboratories have been evaluated and discussed.

Positron emitters may contribute considerably to the radiation from induced radioactivity in accelerator environments. In most cases of thick radiating

objects (magnets, shielding walls) the dose rate from gamma emitters, including the 511 keV annihilation photons from positron emitters, dominates the radiation field. Direct positron interaction in skin tissue and in the lens of the eye may be an important contribution to absorbed dose in cases of thin targets and beam separating septa. Results of calculations and measurements show, however, that the dose to the lens of the eye is limited by limitations placed on whole-body doses. Irradiation from positron emitters gives rise to about the same absorbed doses as those experienced in the case of an electron exposure.

The beta measurement problem at DOE facilities was assessed through the use of a questionnaire and field visits to selected facilities. At 35% of the facilities, the radiation exposures from beta emitting radionuclides are high enough that they must be considered in establishing protection requirements. Measurements were made in several facilities using scintillators, a surface barrier detector plus various dosemeters and survey instruments. Beta dose rates of several mGy.h{sup -1} were not unusual and beta gamma ratios of greater than 30:1 were frequently observed. The agreement between the various measurement techniques was frequently unacceptable.

In the nuclear fuel cycle, the handling of UO{sub 2} pellets results in a significant exposure, mainly due to beta rays. Depth dose distributions have been investigated at source-to-detector distances of 5 to 80 cm using LiF detectors of different thicknesses. Detailed data for the dose equivalent quantities H(0.07), H(3) and H(10) are presented. These data are compared with those found for the use of glazed tiles and ceramics containing natural uranium.

Accelerator-produced, nearly monoenergetic electron beams are being studied for use in obtaining the response of beta particle dosimetry instrumentation as a function of electron energy. Three detection systems were studied: a thin-window ionisation chamber, a thin thermoluminescence dosemeter, and an electron spectrometer. For each of the systems studied, broad spectrum response was measured with standardised sources of {sup 147}Pm, {sup 204}Tl, and {sup 90}Sr+{sup 90}Y. The response of these instruments was also measured in the nearly monoenergetic electron beams. From the monoenergetic electron responses, a function was constructed of response versus electron energy. Broad spectrum response was then calculated using this function and pulse-height distributions of the three beta particle sources, measured with the electron spectrometer. This calculated response was then compared with the measured response. For {sup 204}Tl and {sup 90}Sr+{sup 90}Y, calculated and measured responses agree to within experimental uncertainties.

A tissue-equivalent survey meter for monitoring the (dD/dt)(0.07) and (dD/dt)(10) dose rates produced by betas and photons has been designed and tested. The very thin tissue-equivalent plastic scintillator closely simulates the critical skin tissue layer between 4 mg.cm{sup -2} and 9 mg.cm{sup -2}. The meter is calibrated to read the (dD/dt)(0.07) dose rate directly, and the (dD/dt)(10) dose rate behind a filter. Laboratory measurements of calibrated sources and field tests have demonstrated tissue-equivalent response of the survey meter to betas between 70 keV and 2500 keV and to photons with energies greater than about 30 keV.

For the measurement of low energy X rays emitted by CRT devices at dose rate levels of 1 nSv.h{sup -1}, two different techniques have been used: a phoswich detector inside a steel-shielded room, and a large-area xenon proportional counter for in situ surveys in the workplace. Using a detector-to-screen distance of 5 cm, the area doe rate has been converted into effective dose equivalent. A survey program of 44 VDTs and 65 colour TV sets results in annual dose values of 12 nSv for VDT operators and 3.3 nSv for TVs, which is nearly five orders of magnitude below the exposure due to natural radiation background.

The techniques available for personal monitoring of doses from external beta and low energy photon radiation are reviewed. The performance of currently used dosimetry systems is compared with that recommended internationally, and developments for improving the actual performance are outlined. The subjects

dealt with comprise: the quantity to be measured, the required accuracy of measurement, calibration procedures, and dosemeter design including the main parameters influencing the energy and angular response of the dosemeter, such as detector thickness, filter thickness, dosemeter materials and detector-filter geometry. Improvements in the energy and angular response of dosemeters for the measurement of doses from beta and low energy photon radiation can be achieved essentially through two different approaches: either by using thin detectors or multi-element dosemeters. Their relative merits are discussed.

A review of recent radiobiological data indicates that dose measurements for the skin, eye and testis should be made at depths of 5-10, 300 and 800 mg.cm{sup -2} respectively. Current dosemeters for superficial tissues do not necessarily conform to these depths. The effectiveness of current dosemeters used at CEGB nuclear sites has been evaluated by means of a depth dose study using stacks of thin thermoluminescence (TL) dosemeters. Potential under-estimates of skin dose in general were found to be less than a factor of 2, though this could be as much as a factor of 5 in special cases of exposure to low energy beta emitters. The over-estimate of eye or testis dose was a factor of 2-3.

The depth dose distribution, besides being a function of the beta nuclide, is also strongly dependent on the irradiation geometry, i.e. on factors like distance from the radiation source, area of the radiation source, and additional absorbers. As the response of a personal dosemeter is dependent on the dose distribution within the dosemeter, it is thus also dependent on the irradiation geometry. A Monte Carlo code has been used to calculate the depth dose distribution for a beta nuclide of high maximum energy, namely {sup 90}Y, for different irradiation geometries. With these results the dosemeter responses for the skin dose are calculated for personal dosemeters of different detector and window thicknesses. It is shown that the response of different dosemeters depends markedly on irradiation geometry. Thus the response of, for example, a 0.9 mm thick LiF TLD at a distance of 30 cm from a {sup 90}Y point source is greater by a factor of more than 4 than that of the same detector at the same distance from a {sup 90}Y area source, covered by a 7 mm thick tissue-equivalent absorber.

Extremity dosemeters are usually designed as skin dosemeters and as such should be capable of measuring dose equivalents to the radiosensitive cells of skin. Current designs of extremity dosemeter used in the NRPB extremity monitoring service employ thermoluminescent LiF as the detector in powder form contained in polyethylene sachets or finger stalls. These designs are too thick (30 mg.cm{sup -2}) for the measurement of skin dose. However, Vinten Instruments have developed a new extremity dosemeter with an effective thickness of approximately 12 mg.cm{sup -2} capable of making adequate measurements of beta rays with energy spectra with maximum energies above 0.2 MeV and mean energies greater than 0.06 MeV. Its dosimetric performance has been assessed at NRPB and found to be very satisfactory and trials have been carried out successfully with eleven customers over a six month period. As a result a decision has been taken to introduce the dosemeter into service towards the end of 1985.

The history of exoelectron dosimetry and the results of various laboratories who have applied this method for the detection of beta-rays are briefly reviewed. The properties of promising recently developed BeO thin film dosemeters are described in more detail. In order to study the possibility of skin dose determinations at different depths, such dosemeters were covered with polycarbonate foils of various thicknesses from 1.9 to 19.2 mg.cm{sup -2} and exposed to {sup 147}Pm, {sup 204}Tl and {sup 90}Sr+{sup 90}Y beta sources. The dependence of their response on both foil thickness and mean beta energy is reported.

Microdosimetry with thermoluminescent materials using laser beams gives rise to various specific problems. These are related to this type of heating, and to miniaturisation of dosemeters. Both theoretical and experimental aspects are presented. A reading system has been developed which is intended primarily for use with low penetrating radiation. Limitations and parameters associated with

this technique are consequences of thermal problems. The use of laser beams allow for localised heating, well suited to the measurement of doses which are absorbed by a few micrograms of material. The loss of sensitivity related to the small volume is balanced by a gain related to the fast heating rate. Dynamic thermal transfers, as well as essential elements concerning knowledge and control, are discussed.

In comparison with the transport of neutrons or gamma radiation, beta particles suffer a far greater number of scattering events on their path through matter because of their electrical charge. The characteristic physical phenomena are rather complicated but have been well understood for decades. From the early years of this century statistical descriptions of beta transport such as stopping power and range have been developed and used to advantage. Concepts such as small-angle scattering and range straggling, both using statistical approaches, have been developed. With the advent of fast computers a means of calculating beta transport through matter in complicated geometry has been devised. Good approximations to the beta spectra of the nuclides can be calculated rapidly. Nevertheless, modern Monte Carlo codes for beta transport do not follow single processes, but model beta paths by grouping together many single processes by means of energy spacing. In this way artificially constructed random walks take into account the combined effects of many collisions.

Dose distributions around plane sources of {beta}emitting radionuclides in an homogeneous medium are computed by integrating the {beta}point source dose function. The {beta}point source dose function used for these integrations is a slightly modified formulation of the original Loevinger function; the parameters in this function are presented for {beta}emitters with maximum {beta}energies ranging from 40 keV up to 35 MeV. Results of the integration for different plane sources are presented as analytical formulae; these formulae can easily be programmed. For {beta}radionuclides used in biological and medical applications, the influence of the size of the applicator on the absorbed dose distributions is discussed.

The development of a portable, phoswich-type, field beta spectrometer-dosemeter to measure beta spectra and doses at selected tissue depths in intense mixed beta-gamma radiation fields is described. The techniques used for the evaluation of the surface and depth dose rates based on beta spectral measurements are presented.

An easy to handle dose rate meter has been developed at the Juelich Nuclear Research Centre with a small probe for the energy-independent determination of the dose rate in mixed radiation fields. The dose rate meter contains a small ionisation chamber with a volume of 15.5 cm{sup 3}. The window of the ionisation chamber consists of an aluminised plastic foil of 7 mg.cm{sup -2}. The dose rate meter is suitable for determining the dose rate in skin. With a supplementary depth dose cap, the dose rate can be determined in tissue at a depth of 1 cm. The dose rate meter is energy-independent within +-20% for {sup 147}Pm, {sup 204}Tl and {sup 90}Sr/{sup 90}Y beta radiation and for gamma radiation in the energy range above 35 keV.

A technique for measuring the (dD/dt)(0.07) and (dD/dt)(10) dose rates in mixed beta/gamma radiation fields through the used of a tissue-equivalent detector and portable multichannel analyser has been developed and field tested. Two energy spectra are collected for each measurement, an open window spectrum representing the tissue response to betas plus photons, and a second filtered spectrum representing the photon response. A close approximation to the net beta spectrum is obtained by spectrum stripping, and the (dD/dt)(0.07) dose rate is calculated by multiplying, channel by channel, by a beta energy deposition function. Computer plots of typical field spectra and dose rate calculations are presented.

The characteristics of an extrapolation chamber FWT type EIC.1 have been determined to aid its utilisation as a transfer instrument for the

characterisation of beta radiation field in terms of absorbed dose in tissue. This detector, made of A-150 tissue-equivalent material, is fitted with a window 7 mg.cm{sup -2} thick. It can be used either with ambient air or with a tissue-equivalent gas flow. Some changes have been made to the commercial model (alteration of the variable spacing of the thickness of the cavity, and of the circuit of gas flow) so that it could be used correctly for low energy radiation.

The only measuring method so far known that allows precise and absolute measurements of the absorbed dose rate produced by {beta}rays or soft X rays in a phantom makes use of so-called extrapolation chambers. Fifty years ago Failla developed the first extrapolation chamber and gave it its name. His discussion of requirements can be briefly summarised: an extrapolation chamber should have no walls and no air volume. Whether these limiting conditions can be fulfilled can be demonstrated by measuring cavity ionisation according to Bragg-Gray theory or exposure under conditions of secondary electron equilibrium. The dependence of the local distribution of charge carriers in the collecting volume on the chamber gas pressure is discussed in order to elucidate the difficulties arising from the variation of the mass of the chamber gas in an extrapolation chamber.

The response of survey instruments in common use (portable devices, pen dosemeters) has been studied for beta rays of different energies ({sup 147}Pm, {sup 204}Tl, {sup 90}Sr + {sup 90}Y). In addition the effect of the geometrical configuration of the radiation field has been studied with variations of the source-detector distance as well as the dimensions of the beam (point sources and extended sources and beams with flattening filters).

Eight communities in the lower Aare valley in the northern part of Switzerland are now receiving district heating service from Beznau nuclear power plant. The Refuna (Regionales Fernwaermenetz Unteres Aaretal) heat supply system itself is the precursor of a much larger heat transport system which could eventually extend into Zuerich. Reduced oil consumption and avoidance of air pollution that accompanies the oil combustion are the driving influences behind the nuclear CHP movement in Switzerland.

The aim of this workshop was to exchange views on the characterization, waste management and safety analysis in order to establish guidelines for future research into the long-term performance of low- and intermediate-level waste packaging for underground disposal. Extensive tests were carried out to study leaching of wastes from different matrix materials. Various scenarios were investigated. (U.K.).

In hostile environments, transmitting information as ultrasonic Lamb wave pulses has advantages, since the stainless steel strip serving as a waveguide is very durable. Besides attenuation, velocity dispersion (inherent in Lamb waves) can be important even in fairly short guides. Theory shows that unlimited propagation of a pulsed r.f. envelope is possible, even with dispersion present. The constant group velocity needed would favour asub(o)-mode pulses over other modes, provided ordinary attenuation is small. An approximate formula indicates the useful range of a pulse, when group velocity does vary.

By affixing a high impedance acoustic plate the thickness of which is lambda/4 and/or 1.5lambda, 3lambda/4, to a piezoelectric vibrator, high-sensitivity transducers with multiple channels and usable in liquid acoustic media were developed. These transducers were tested for the ultrasonic inspections in the liquid sodium used for heat exchange in unclear reactor and for two way communication in water, and the results obtained were highly satisfying. These transducers have a simple construction and are easily fabricated; also many other applications can be considered.

A passive acoustic imaging system for acoustic source location with no restriction on source character is being developed for thermal-hydraulic components. The system is particularly useful in locating continuous or quasi-

continuous acoustic emission sources such as leaks in steam generators or rapid rattling of tubes in steam generators. In the imaging system to be described, acoustic signals that emanate outward from the source, through the medium, are detected by an array of low-frequency accelerometers. These time domain functions are combined with a mesh mapping algorithm to produce a spatial image showing the location and intensity of the noise source.

The authors construct the unconstrained superfield formulation of D=2, N=1 supergravity and give general matter couplings. A new type of non-linear {sigma}model that possesses (local supersymmetry)x(local supersymmetry) is described.

Daresbury Laboratory has now been in existence for over 20 years. Early high energy physics work utilized electron and photon beams from the 5 GeV electron synchrotron NINA and use was made of the synchrotron radiation emitted by the circulating electron beam for a range of studies. Following the closure of NINA, activities at the Laboratory centred on a 2 GeV electron storage ring used as a dedicated synchrotron radiation source and a 20 MV tandem Van de Graaff accelerator which provides a wide range of accelerated ions for nuclear structure studies. Both machines have been in regular and effective use for several years and have established international reputations in their respective fields.

This volume contains over 130 papers, grouped into 13 chapters, presented at the conference. The topics include bulk materials, epitaxial growth, photochemical processes, process technologies, characterisation, new devices, digital and analogue devices and optoelectronic devices. Six papers, where ion implantation or ion bombardment of the gallium arsenide or related compound is involved, are indexed separately. (U.K.).

In GaAs lateral epitaxial growth over a tungsten grating, surface atom migration is enhanced by ion irradiation during molecular beam epitaxy. Lateral overgrowth is seeded by epitaxial deposits formed on the GaAs(001) surface openings onto a line and space tungsten grating. The growth aspect over a tungsten grating is improved as surface atom migration increases from polycrystalline growth on tungsten to rather flat, single crystalline growth. Due to surface atom migration enhanced by ion irradiation, a single crystalline layer is obtained at a low substrate temperature where polycrystalline growth takes place without ion irradiation.

Growth-interrupted and selectively ion implanted AlGaAs/GaAs multilayer interfaces have been studied by C-V and photoluminescence intensity measurements. The samples were prepared with a growth system consisting of an MBE chamber and a 100kV focused ion beam implanter (FIBI) connected to each other through an ultrahigh vacuum (UHV) transfer chamber. Results indicate that the interfacial properties are comparable to those of continuously grown interfaces in the case of a through process in the background vacuum of 5x10{sup -10}Torr. This is confirmed by successful operation of a new DH laser, which contains the selectively Si-implanted Alsub(0.3)Gasub(0.7)As cladding layer for current confinement.

Properties of Si-implanted GaAs and In/sub 0.53/Ga/sub 0.47/As activated by short-term halogen lamp annealing have been investigated. Best results in GaAs are consistently produced by a two-step annealing scheme.

Be, Mg, Zn and Hg have been implanted in In/sub 0.53/Ga/sub 0.47/As. For Be, Mg and Zn, the quick diffusion of the implanted impurities yields difficulties to get a p-type layer after implantation and annealing. On the other hand, mercury does not diffuse towards the bulk and behaves as an acceptor dopant impurity -Thin p{sup +} layers are obtained in Insub(0.53)Gasub(0.47)As by mercury implantation - A comparison based on the chemical profiles and on the electrical results is performed for the four acceptor impurities.

The disordering of Alsub(0.5)Gasub(0.5)As-GaAs multiquantum wells induced by focused Si ion beam implantation and subsequent annealing at 850{sup 0}C under

As pressure has been studied. Disordering is confirmed by depth profile of Ga Auger intensities and the scanning electron microscopy image of the cross section of multiquantum wells. Ion dose and accelerating energy dependence of disordering indicates that the Al-Ga interdiffusion is suppressed by implantation-induced-defects and enhanced by rapid diffusion of Si atoms at high concentration.

Based on measured DC performances of high-doped channel and short gate GaAs MESFETs at 300 and 77K, the short-channel effects, surface depletion behavior and g/sub m/-R/sub s/ relation are investigated and discussed. Using solution of a series of equations, the electron saturation velocity V/sub s/ is cleverly calculated. For 0.3 {mu}m gate devices, V/sub s/ of 300K increases from 1.4 x 10{sup 7} to 2.5 x 10{sup 7} cms{sup -1} with increasing of negative gate bias, but remains constant at 1.4 x 10{sup 7} cms{sup -1} for 0.6 and 1.1 {mu}m gate devices. V/sub s/ of 77K is about 10-20% higher than that of 300K.

The need to optimise radiation protection procedures in diagnostic X-ray examinations has been stressed by the ICRP. A quality assurance programme is almost essential to ensure consistent and reliable performance of X-ray units over a period of time. In the context of an analysis of diagnostic radiology in Irish hospitals, a number of measurements were made to check the radiation protection features of X-ray rooms and the performance characteristics of X-ray units in routine operation. The results are presented of the first series of quality assurance measurements.

Scientific associations in Italy such as the Assoziazione Italiana di Radioprotezione (AIRP), the Societa Italiana di Biologia e Medicina Nucleare (SIBMN) and the Assoziazione Italiana di Radiologia Medica e Medicina Nucleare (SIRMN) have been working on the problem of patient radiation protection for many years; their latest activities are described. Principal features and aims of the NEXT programme and the programme ''Dose and quality image in mammography'' will follow. Local administrations and Health Physics Services are involved in programmes on Genetically Significant Dose (GSD) evaluation or quality assurance: examples of these programmes are shown. Lastly, problems related to the education of radiological operators and radiologists are dealt with.

So far no real national quality assurance programme exists in France. No such programme could exist without good prior knowledge of material and practices in the radiodiagnostic field. A critical review is given of the French situation as it appears in a national survey carried out by the CEPN (collective dose evaluation, and assessment of X-ray examinations in 1982) and a local study of the SFPH (measuring the absorbed dose delivered when simulating a typical radiograph on about 50 X-ray units). The main parameters analysed are: the physical ones (kV, mAs, dose, optical density, beam quality), the fluoroscopy screening time, the number of X-ray films, their sizes, the films wasted. The variations of these parameters are considered more specifically in relation to the age and type of X-ray equipment, the type of examinations performed, the activity sector (public hospitals and private clinics), the practising physician's speciality (radiologist or not). The results of the surveys present large variations among these parameters. A joint attempt is made to determine the more important parameters necessary for implementing a national quality assurance programme in France.

Quality assurance has been demonstrated to be an effective approach in optimising the conduct of diagnostic X-ray procedures. To encourage acceptance of quality assurance, the Center for Devices and Radiological Health (CDRH), formerly the Bureau of Radiological Health, has taken an educational, rather than a regulatory, approach, and has promoted the concept of quality assurance as a voluntary facility-based programme, through a formalised recommendation, which has been supported by technical manuals and cooperative interchanges between government, industry, professional societies and the clinical community. As a result, an effective quality assurance programme has become a standard of good practice in the United States.

Responsibility for enforcement of regulations and standards for diagnostic X-ray equipment in Canada is shared among the federal and ten provincial governments. Practically all equipment is imported. A large number of units are located in small clinics often in remote areas, where outside assistance to check the performance of equipment is not readily available. These conditions make it necessary to coordinate the regulatory and quality assurance activities. Requirements on stability and reproducibility have been included in the federal regulations to facilitate quality control. A joint federal-provincial group was established to prepare quality control criteria and to initiate a nationwide quality assurance programme.

An analysis of the results of Quality Assurance in one of the largest Health Regions of the United kingdom is presented. The results were obtained on the basis of a protocol widely followed in the UK, which was set up by the Hospital Physicists' Association. The part of the protocol described covers quality assurance of X-ray tubes, generators and image intensification systems. The method includes quantitative tests of kV (using a film penetrameter), focal spot size (using a star test pattern), filtration (using HVL curves) and radiation output of the X-ray tube. In addition, for the imaging system, the video voltage and automatic brightness control are measured, together with subjective assessments using the Leeds Test Objects. The results show that an unacceptably high percentage (17%) of new equipment does not function satisfactorily or as specified on installation.

An investigation has been carried out to check the technical parameters of X-ray equipment. Several methods have been used and studied both from the practical and theoretical points of view. Considerations and suggestions are presented.

One hundred and eighty of about 800 X-ray film processors used in the GDR were checked sensitometrically. Sensitometric control strips, pre-exposed at a certain level, were mailed, processed and re-mailed; fog, the density of a medium-density step and a density difference were then determined. Reference data were obtained by processing exactly according to the recommendations of the film manufacturer; the mean of fog measurements equals the reference value. Seven per cent of processors produced fog which was unacceptable. The mean of the medium density measurements was 10% below the reference value. Five per cent of all processors operated at unacceptably high, and 16% at unacceptably low, density. Since failures in processing are commonly compensated for by changing radiation doses, consequences for radiation exposure are obvious. Analysis of data on operating parameters supplied by the users identified the disproportion between developer replenisher rate and film load as the main reason for this unsatisfactory situation.

The German standards for image quality assurance in X-ray diagnostic work are presented. A standardised control of film processing is mentioned and some problems arising in connection with a simple test device for constancy checking in direct radiography are discussed. A few samples of this test device are undergoing trial. Finally some essential points for the expected cost are given.

NEXT (Nationwide Evaluation of X-ray Trends) is a programme originally designed at the Center for Devices and Radiological Health (CDRH) (USA) and then adapted to Italian conditions. Since November 1983 an improved computer code has been available. For each apparatus surveyed, all the parameters influencing patient exposure are collected and on this basis the doses to the most important organs of the patient's body, such as thyroid, bone marrow, uterus and gonads, are computed. Equipment and radiological techniques causing excessive doses are easily picked out and may then be adjusted or corrected; using the same data, the relevant authorities can choose the most adequate programme to improve radiation protection of the patient. Results of a representative sample from the region of Emilia-Romagna are presented, showing how this programme could influence quality assurance.

Many quality assurance procedures in diagnostic radiology require the use of a phantom to simulate the X-ray attenuation of the patient. It is always desirable

and often critical that the phantom transmit not only the same quantity but also the same quality (spectrum) of radiation transmitted by the patient. An analytical method has been developed for the design of tissue substitutes and test objects that satisfies these requirements. The tissue substitutes and test objects that result from this design procedure match, with very good accuracy, the spectral characteristics of the material being simulated. In addition, they can be constructed from a variety of materials. This allows the designer to select materials to satisfy other requirements such as cost, availability, convenience, constancy of properties (important if many identical phantoms are required), or the need for some unrelated physical property, e.g. electrical conductivity. The material to be simulated may be specified by density and chemical composition, or by its thickness and a minimum of two X-ray attenuation measurements, at different energies or with different spectra. The method and present sample results are described. The role of this procedure in developing standard attenuation phantoms for exposure surveys on chest and abdomen imaging systems equipped with automatic exposure control is also described.

A range of test objects has been developed to assess the imaging performance of conventional and digital radiological imaging systems. These test objects have arisen as a result of involvement in both the laboratory evaluation of radiological imaging systems and the routine maintenance of such equipment in a large diagnostic radiology department. The philosophy behind the design and application of the test objects is briefly described. Particular attention is paid to the advantages of using the threshold-contrast detail-detectability technique to assess overall imaging performance. The great importance of ensuring optimum imaging performance prior to clinical acceptance is stressed. A strategy for implementing the test objects in a clinical department is present. The diagnostic information content of the clinical images which result measures the success of the quality control procedure adopted.

The method by which the VICTOREEN Model 6000A NERO makes measurements is presented, followed by the meaning of these measurements and how they are displayed. Measured quantities include the instantaneous kilovolt (kV) peaks, time-integrated effective kVp, exposure time, exposure output, and a heavily filtered radiation waveform. The simultaneous measurement of these quantities in one exposure is important for X-ray QA and diagnosis. An additional exposure with added absorber allows a half-value layer calculation. Calculations of relative mAs and mA from the measured quantities kV, mR, s. for sequential exposures are discussed.

A simple and inexpensive test tool is described, for checking kV-consistency both in fluoroscopic and radiographic modes. It is designed primarily for routine checking to recognise changes in effective kV. A plexiglass body with boreholes in which copper discs of different thicknesses are inserted is depicted on a film or the TV screen via the image intensifier. Due to the very different absorption properties of copper and plexiglass the relative transparency of the copper discs changes markedly when the tube voltage is varied. The copper step-associated with a reference number-having transparency equal to the surrounding plastic can be used as a good index for tube kilovoltage. The accuracy of the visual assessment is about +-2 kV at 60 kV.

Devices and computer programs used for evaluating the principal parameters affecting dose and image quality are described. The devices are calibrated using an X-ray facility assembled for the purpose.

Conversion factors for the calculation of organ doses from the technical parameters for typical radiographic techniques are presented.

An inexpensive and simple test device was developed and used in a field study to evaluate entrance dose, dose to an intra-oral film, filtration and field size under routine conditions in more than 200 dental practices. The test device consists of two films of different speeds and a set of five thin copper filters for a filter-analytical determination of the radiation quality. Dentists were asked to expose the test device when examining a molar tooth. Together with a

short questionnaire, describing the respective conditions of film exposure and processing, the test device was returned for development and evaluation. The main result was the evidence of a significant dose reduction compared to the findings of similar studies performed in 1970 and 1975. This reduction is due to a general shift to lower values and a complete disappearance of values above 45 mGy (5R) which in 1970 were still more than 15%. In the same way the number of facilities showing insufficient filtration or collimation had decreased. Nevertheless, a large spread of dose values could still be observed, ranging from 2.5 mGy (290 mR) to more than 30 mGy (3.4R) for the entrance dose. The most striking result, however, was that such an important parameter as the speed of the films used at the respective unit had no impact on the entrance dose.

Dose reduction methods, like the use of high sensitivity film screen combinations, have become more common in Germany. To find out the influence of these measures on the dose to patients a survey was started in 1983 to collect dose values under routine conditions at mammographic facilities. Three hundred hospitals and small clinics were asked for cooperation and finally about 160 agreed to participate. The participants have to expose a simple phantom, sent to them by mail, together with the film or film-screen combination commonly used at the unit. The developed films and two sets of three CaSo{sub 4} TL-dosemeters mounted on the entrance and exit surfaces of the phantom are returned to the Gesellschaft fuer Strahlen- und Umweltforschung (GSF) for evaluation of film density and surface dose. In addition the participants are asked to answer a short questionnaire on the conditions of film exposure. Preliminary results on about 130 participants do not indicate a clear separation of the three routinely applied techniques (non-screen film, screen-film, and screen-film with anti-scatter grid) as expected. This demonstrates that even a distinct increase in image detector sensitivity does not always correspond to a comparable decrease of dose to the patient.

Absorbed doses and image quality in mammography units have been investigated at 12 institutes in the Netherlands. The dosimetry was performed in a mammary phantom with an ionisation chamber and thermoluminescence dosimeters. The dose received per mammoradiograph as derived from the ionisation chamber measurements differed greatly among the various hospitals. No correlation was found between the score of the image quality and the mean absorbed dose. A comparison of the two dosimetry methods revealed that the doses at the entrance surface derived from TLD were considerably lower than those from the ionisation chamber. The absorbed dose values determined are higher than those obtained by others. This might be due to an underestimate of the dose as measured by other groups with TLD but also to the use of an incorrectly low conversion factor from exposure in air to mean absorbed dose in the breast. For a number of hospitals the mean absorbed dose values are higher than the acceptable dose limit of 2 to 2.5 mGy per examination. Several hospitals have already made provisions to reduce the dose levels without loss of diagnostic information.

The significance of a measurement of the product of exposure and the irradiated surface are (R.cm{sup 2}) in the radiological protection of the patient has been recognised in many diagnostic radiology departments. A frequently used instrument for this type of measurement is the Diamentor. This report describes the development of a calibration and evaluation technique which is based on the utilisation of the secondary standard of exposure which links the Diamentor directly to the standards laboratory. The method uses beam collimators of well-defined size to determine the radiation beam area precisely. This allows a high precision of calibration to be achieved. The energy dependence of the chamber and beam attenuation in chamber walls were investigated in detail and suitable correction factors have been derived. It has been demonstrated in the course of this work that individual chambers in a large department can be calibrated by comparison technique with one chamber acting as a carefully calibrated standard.

A knowledge of the spectral-energy distribution of the primary beam is required for the evaluation and optimisation of image quality. A mathematical model was studied and applied, in order to compute theoretical primary spectra from

diagnostic X-ray beams. The method used is described and some calculated spectra compared with HPA spectra (1979) are presented. Exposure measurements have also been included, for comparison with the calculated values.

A method has been developed for direct measurement of Signal-to-Noise ratio performance on X-ray TV systems. To this end the TV signal resulting from a calibrated test object, is compared with the noise level in the image. The method is objective and produces instantaneous readout, which makes it very suitable for system evaluation under dynamic conditions.

In a previous study a lucite phantom with several physical elements embedded, such as lead gratings with varying line widths, etc., was exposed at 200 X-ray installations in Bavaria, Federal Republic of Germany, by a conventional diagnostic standard technique. One of the parameters investigated was the local resolution achieved, determined visually by examination of the grating images. The same radiographs have now been used in a retrospective comparative study, based upon a quantitative analysis of TV images of the films. The films were positioned on a commercial illuminator screen and looked at by a TV camera through a simple magnifying optical system. The video signals were digitised, resulting in a pixel distance of 50 {mu}m. In a first approach the edges of the broad frames of the lead gratings were adjusted vertically and the normalised sum of all 256 TV scanning lines taken as the edge function f(x). This was differentiated and suitably Fourier-transformed, delivering the modulation transfer function (MTF). The MTF can be analysed in several ways to describe quantitatively the maximum local resolution achievable. Correlation of some frequency measurements with the visually determined line resolution is generally good.

The direct measurement of X-ray spectra from an X-ray machine is used for the reduction of the dose to the crystalline lens and for image optimisation in dacrygraphy. A portable CdTe detector, an ionisation chamber MDH, RT-Humanoid phantom and LiF TL dosimeters are used for the dose measurements.

As part of a national survey to assess somatic doses arising from diagnostic radiology in the UK measurements are being carried out on patients undergoing ten important types of X-ray examinations at a random sample of 20 hospitals. The measurement protocol adopted involves the use of a Diamentor exposure-area product meter to deduce the mean total energy imparted to the patient, and also thermoluminescent dosemeters (TLDs) attached to the patient's skin to allow the estimation of doses to all the organs of interest. The design of the survey and the techniques that have been developed are outlined and a preliminary analysis of some of the data collected at the first ten hospitals of the sample is presented. Histograms of energy imparted and entrance skin dose per film for selected examinations indicate the often wide range and skewed distributions of the measured doses. Knowledge of the reasons for the spread in patient doses occurring in practice, provided by such surveys, is clearly of importance to the efficacy of quality assurance programmes aimed at maintaining optimal radiological diagnosis.

With a view to minimising the dose absorbed by the paediatric patient during radiological investigations, the most usual X-ray examinations performed in paediatrics were checked in order to standardise and optimise the techniques used. The present study deals with the quality control of the X-ray beam used in radiological diagnosis of young patients, particularly considering that hips and pelvis pathologies can be widespread and that very often it is not possible to shield the patient's gonads during the examination. The electrical and geometrical parameters which minimise the absorbed dose but are compatible with obtaining valid diagnostic information are selected. An anthromorphic phantom reproducing bone and lung inhomogeneities was constructed to the average size of a 12-month-old baby. Inside the phantom TLD 4F 100 dosimeters were located in order to evaluate the absorbed doses. The technique which proved more convenient is indicated and suggested for routine work.

During the last three years a quality control programme in the conventional radiodiagnostic field has been conducted. The programme surveyed 50 X-ray tubes and four automatic processors, and the apparatus were of different types, from simple chest units to image intensifier systems. The analysis of the results concerning the control of physical, geometrical and image parameters and processors, cassettes and other accessories is instructive. A quantification and classification of the film reject rate on 1806 radiological examinations with 5011 films showed that it was 6.2%; the causes were explored and analysed. From past and current experience some proposals for studying and carrying out a suitable quality control programme in a big hospital are made. It is possible to identify three operational levels: first, controls performed by the technical service staff (processors, accessories, geometrical parameters); second, the control of physical parameters and imaging, the analysis of results and programming of repairs by the physicists; third, modification of apparatus and work by service engineers.

Quality Assurance (QA) in diagnostic radiology denotes procedures and checks which serve to maximise the benefit/cost ratio, where ''benefit'' is derived from correct medical diagnoses and ''cost'' includes the indirect costs arising from radiation-induced detriment. The ultimate goal is to enhance the information content of images, but as yet there is no way of measuring image quality routinely in clinically meaningful terms. The relationship between patient entrance exposure and image quality is discussed, with particular reference to the problems encountered by the HARP Commission (''Healing Arts, Radiation Protection'') in Ontario, Canada. The Commission is drafting legal regulations which will include a requirement for QA programmes in all radiological facilities. A partial balance sheet is presented for quality assurance in Canada involving both local QA and provincial X-ray inspectorates. It is assumed that such a programme will reduce the population dose-equivalent by 50% at a cost estimated at dollar1500 US per man.Sv averted (1981 dollars). QA is considered to be cost-effective on the basis of the reduction of radiation detriment alone, other benefits being substantial but difficult to quantify.

For the past two years the staff of the Merseyside Regional Radiation Protection Service have worked closely with the radiological staff of a 16-room X-ray department in applying quality assurance. The QA programme included reject analysis of X-ray film and checks on X-ray equipment performance. The results and the effectiveness of the methods employed are discussed.

Evaluation of the tolerance limits of X-ray image density accepted by the radiologist shows that for different kinds of examinations, deviations of more than 50% from optimal density lead to images which cannot be used diagnostically. Within this range diagnostic accuracy shows a distinct maximum and diminishes to the limits by 20%. These figures are related to differences in the intensifying factor of screens, sensitivity of films, sensitometric parameters of film processing as well as the doses employed with automatic exposure control devices, measured in clinical conditions. Maximum permissible tolerance limits of the whole imaging system and of its constituents are discussed using the Gaussian law of error addition.

Various manufacturers offer a great number of measuring instruments for non-invasive high voltage measurements in X-ray units. These are either special film cassettes, test plates or electronic kV measuring instruments. The efficiency of these instruments has been studied with regard to accuracy, resolution, reproducibility and handling. As far as their accuracy is concerned, all instruments tested are suitable for measurements in X-ray generators (film cassettes between 3 and 5%, electronic measuring instruments between 2 and 3%). High voltage measurements were performed in several X-ray installations for examining the accuracy of high voltage at the different control panels, their reproducibility and long-term constancy. In some units considerable current fluctuations and deviations up to 20% of the preselected voltage value (nominal value) could be found. The average deviation in all installations studied increases with the chosen voltage.

When accepting a CT scanner it is important that the specification be checked in relation to mechanical and electrical safety, mechanical accuracy and imaging parameters. The latter include low and high contrast resolution, radiation dose, noise, uniformity across reconstructed area, CT number scale, slice profile and artefact production. The methods of determining these quantities and their frequency of measurement for routine quality assurance purposes are discussed. The importance of the image display and hard-copy devices are stressed.

A theoretical model has been developed which describes physical imaging performance in mammography. This model, along with a number of physical constraints, such as the relationship between focal spot size and X-ray output, has been subjected to a numerical optimisation procedure. The optimisation was performed to minimise patient dose without changing image quality from that obtained with a standard reference system. The resulting optimal system is predicted to require approximately one-third the dose required by the reference system. In order to verify the predictions of the optimisation a real mammographic imaging system that has the same parameters as the theoretically predicted optimal system has been assembled. Preliminary experiments indicate that this system requires approximately 40% of the dose required by the reference system. The optimal system is described, the experimental approaches for verifying image quality discussed and results of some additional experiments presented. The sensitivity of the optimal system dose to improvements in various imaging chain components is described and the implications for the allocation of future research effort discussed.

One of the most direct ways of reducing health costs and patient exposure is to avoid all radiological investigations which are not essential for the achievement of a reliable diagnostic methodology with the lowest acceptable dose and at a moderate cost. An objective of the need for various X-ray procedures was started more than 10 years ago in the USA and the UK. WHO has initiated efforts towards a wider understanding of this subject by organizing three meetings: Brussels 1977, and Neuherberg 1979 and 1981. These meetings were followed by the Scientific Group Meeting which was held in Geneva in 1982, the report of which has been published entitled A Rational Approach to Radiodiagnostic Investigations. This report summarises experience gained in relation to the rational use of X-ray investigations, with the aim of encouraging radiologists and medical specialists to restrict the practice of major and commonly used radiodiagnostic investigations to those which are clinically justified.

Firstly it is emphasised how difficult it is to define the concept of optimisation in diagnostic radiology. Physicists, engineers, doctors and technicians often take differing viewpoints. In order to achieve the aim of improving medical X-ray examinations, three courses of action must be adopted: firstly, technical improvement and regular inspection of the equipment, then better training for technicians and also doctors. In this respect it should be mentioned that in Switzerland for example, of approximately 5 million X-ray pictures taken by doctors (excluding hospital and dentists) for 17 examination types, approximately 3 million (61%) originated from nonradiologists. The question could be asked finally, what criteria can be used to assess whether, in any one country, the recommendations of the national and international authorities for reduction of the radiation exposure of the population have been followed. In this respect, some thoughts are put forward on population indices such as Genetically Significant Dose and Bone Marrow Dose.

Radiological facilities must be adapted to the needs of infants and children, and examination technique must be modified. Quality assurance starts with the questions: ''Is this radiological examination really necessary. Will it influence the diagnosis as well as the selection of therapy and patient management. How much effective dose to the patient is justifiable. Does the expected benefit for the patient outweigh possible risks and unavoidable burdens''. Considerations concerning the effective quality are much more important in paediatric radiology. Otherwise, technical quality control and

assurance must be adapted to the specific techniques of paediatric radiology. Many adjustments (exposure time, automatic exposure control, tube voltage, fluoroscopic dose rate, film-screen performance etc.) must be made near the lower technical limit. The range of tolerable variations is small. Devices unknown in general radiology must be tested. Methods and phantoms for quality control, therefore, must take into account these specific conditions of paediatric radiology.

Radiation resistance and sensitivity of polystyrene and related polymers have been studied by pulse radiolysis and laser photolysis techniques and are explained by energy and electron transfer and reactivity of transient ionic and excited species.

A brief account is given of the 1985 Cargese Workshop on magnetic reconnection and turbulence.

A report is given of the 17th ECLIM (European Conference on Laser Interaction with Matter).

For PCMI analyses of power ramps it is necessary to have good theoretical information concerning the mechanical condition of the clad - especially the hoop stress - during and after a power ramp. As a tool for such analyses, KWU has developed the computer code SENATOR which covers the mechanical analysis in a slice of a fuel rod. For SENATOR calculations the initial conditions of a power ramp are evaluated by the fuel rod code CARO. The first paper about the SENATOR code was presented at the 6th SMIRT conference (1981). In the meantime, the code has been refined and an improved version is described in this paper. The mechanical models in the code can be characterized by the following features: (a) The pellet is divided into three concentric zones with different axial boundary conditions. A submodel defines the axial coupling between fuel and clad. (b) The SENATOR code calculates average stresses and strains in the clad. Combined with concentration factors - as derived from FEM analyses - local stresses and strains can be calculated.

The quality of a radiograph is determined by the diagnostic information it provides. This depends upon the visual detection of diagnostically relevant structures. The technical radiographic requirements are dependent upon the physical measurements and the physiological and optical conditions. Such physical factors as spatial resolution, contrast and noise are quantitative measurements, which must be oriented to the qualitative visual characteristics of the radiograph. The influence of subjective perception and complexity of structural noise on the detectability of details and structures particularly demands attention. Since radiographic quality depends upon the detection of diagnostically relevant structure and features, it is important to define these parameters on the basis of extensive radiographic analysis and the corresponding clinical findings. The diagnostically relevant radiographic parameters and image details and critical structures have been worked out for the examination of the lungs, colon, stomach, urinary tract and skeleton. Good image quality requires coordination of the physical-technical parameters with the visual ability of the observer, since only in this way can the diagnostic information be represented with sufficient clarity.

The role of quality assurance in the overall framework of costs, risks and benefits in X-ray medical diagnosis is outlined. Justification for implementing quality assurance is highlighted in terms of the nature and extent of radiological practice, the levels of exposure involved and the cost of providing the service. Quality assurance is discussed in terms of (i) quantitation/assessment; (ii) administration/ management; (iii) organisation; (iv) implementation. In particular, the need to implement quality assurance cost-effectively is discussed.

A report is given of the most recent assessment of doses from medical exposures published by UNSCEAR in 1982. Medical irradiation is characterised by the high instantaneous rate of exposure, by the fact that it generally involves limited

parts of the body and by the large variability of the doses received by the patients. Under such conditions, expressing the doses as averages over the whole exposed population has little significance; on the contrary, collective doses may provide some indication of the overall impact of medical sources. It is estimated that the annual collective effective dose equivalent from medical diagnostic procedures may amount to about one-half of that received from natural sources in developed countries. In developing countries the same quantity could be ten times lower in view of a correspondingly lower rate of examinations. Thus, the annual collective effective dose equivalent applying globally over the whole world could amount to about one-fifth of the collective dose equivalent from natural sources.

A number of international bodies have attempted to stimulate wider interest in Quality Assurance in X-ray departments. A major initiative has been taken by WHO with the publication of its recommendations in 1982 under the title Quality Assurance in Diagnostic Radiology, in which they indicated the action that should be taken at various national, professional and local levels. The recommendations of ICRP in Publication 26 point to the need for quality assurance programmes that will obtain optimum diagnostic information at minimum cost and minimum patient dose. ICRU have been considering the need for cost-effective quality assurance programmes and the specification of standards for image quality. The IEC and various manufacturers' organisations have begun to consider the part they can play in setting up quality control procedures. The most active group has been the ISRRT, which has arranged a series of seminars and workshops for radiographers in various parts of the world. Future needs for international support lie in the provision of training programmes, the publication of comparative statistical data and the development of image quality standards.

A presentation is given of some characteristics of the International Electrotechnical Commission (IEC). This is followed by a short discussion of general aspects of quality assurance in the diagnostic department. From this discussion it becomes apparent to which aspects of quality assurance IEC can contribute. Within that framework a working group of Sub-Committee 62 is at present active in developing a standard on quality assurance for diagnostic X-ray systems. The standard will contain a set of constancy tests that is claimed to allow a balanced quality assurance programme. The democratic procedure of IEC should guarantee that the proposed standard gains wide acceptance.

APOLLO II is a new, multigroup transport code under development at the Commissariat a l'Energie Atomique. The code has a modular structure and uses sophisticated software for data structuralization, dynamic memory management, data storage and user's macrolanguage. This paper gives an overview of the main methods used in the code for a) multidimensional collision-probability calculations, b) leakage calculations and c) homogenization procedures. Numerical examples are shown to demonstrate the potentialities of the modular structure of the code and the interest of the novel multilevel flat-flux representation used in the calculation of the collision probabilities.

In a power LMFBR, the hexagonal assemblies are separated by sodium gaps. Due to the relatively high mean free path of sodium, these gaps introduce a streaming effect which increases the absolute value of the leakage component of the reactivity, compared to the case where sodium is simply smeared with the assembly material. This effect is enhanced in accidental situations where sodium is voided. A theoretical method, based on a reasonable approximation, is proposed for the calculation of these effects. Numerical values of the reactivity changes are given and show that the streaming effects are important. Values of the reactivity change are also given for another accidental case, in which the core is compacted is such a way that the gaps disappear. Some critical facilities contain a 2D array of perpendicular void gaps. A particular method for the calculation of the streaming in such a lattice is proposed, and numerical values are given. This is important for assessing bias factors in the interpretation of integral experiments.

A new calculation scheme is adapted to evaluate neutron fluxes in the reactor cavity and the containment of next french PWR. In this scheme a large part is given to Monte Carlo method, coupled with SN-method, in order to take into account multiple neutron diffusions and the complexity of the reactor geometry.

The FLICA IV computer code is devoted to the thermal analysis of nuclear reactor core, it includes an interactive environment for pre and post processing and computational modules for three dimensional two phase flow transient computations. This paper will describe developed numerical methods for 3-D two phase flow transients. 4 refs.

Significant advances on both ex-core and in-core instrumentation and protection system have been achieved in France within the last eight years. The most significant achievement is the design, qualification and implementation of the multisection ex-core detectors which are part of the new Integrated Digital Protection System (SPIN) installed on all the 1300 MWe plants in France. Before this, theoretical works and on-reactor tests have been done, starting in 1978 on the BUGEY-2 reactor with a prototype detector, continued in 1981-82 with a protection system mock-up on TRICASTIN-3. These results made it possible to design the new protection system of the 1300 MWe plant program, the first units on operation being PALUEL 1 and 2, which came on line in 1984. During the last years, other tests were made, using fixed in-core instrumentation based on core outlet thermocouples, self-powered detectors and gamma thermometers. The use of this kind of instrumentation is presently being contemplated, probably as a complement of the present instrumentation.

The use of high electric field tunnel injection is studied in this report together with the induced shifts between threshold voltage and injection voltage, of a characterization method of hardening and traps. The method allows to find trap density and cross section.

The log f values for allowed and first forbidden unique beta + and beta - transitions for elements situated between carbon and strontium have been calculated as a function of transition energy which value is comprised within 0.1 and 25 MeV. For 6 {le}Z {le}38 and for transition energy higher than 10 MeV, the orbital electron capture to beta + emission rate is less than 10/sup -3/. Beyond 10 MeV, the electron capture contribution is negligible.

The decay of /sup 124/Ba to the levels of odd-odd /sup 124/Cs has been studied with on-line mass-separated sources delivered at the ISOCELE facility. The energy level scheme has been established from {gamma}-ray singles, {gamma}-{gamma}-t coincidence and e-{gamma}-t coincidence spectra. Spin and parity of several low-lying levels have been assigned on the basis of internal conversion coefficient measurements and {beta}branchings. A completely new level pattern including approximately 50 levels and /sup 180/ {gamma}-rays is proposed for /sup 124/Cs. Several features of this level scheme are discussed and compared to those of neighbouring isotopes.

Recently Bowman et al. found that in the reaction /sup 139/La + /sup 12/C at 50 MeV/u a compound nucleus is formed. We simulate this reaction with a numerical solution of the VUU equation and indeed find that for a central collision the system fuses and equilibrates after 90 fm/c.

We present a study of the temperature dependence of the energies of isoscalar giant resonances within a semi-classical model, in the framework of the subtraction procedure of Bonche, Levit and Vautherin. This prescription allows a consistent treatment of continuum effects, which play, as we show in detail, a crucial role in the description of excited collective motions. Special attention is paid to the monopole resonance for which 3 moments of the strength function have been calculated. We find a weak temperature dependence of the studied resonance energies (l=,2,3,4).

First measurements of light particle correlations at very small relative angles (0.1/sup 0/) had been obtained with the specific interferometer EMRIC at SARA. This first analysis will emphasize the interest of such an angular resolution.

A part of the oscillations of the phase space distribution function is shown to be a surface effect. A series expansion for this function is given, which takes partially into account this oscillatory structure.

Results based on a sample of events with large missing transverse energy corresponding to 715 nb/sup -1/ of data from the UA1 experiment at the CERN antipp Collider are presented. High transverse momentum tau-leptons from W decays are observed for the first time through their semi-hadronic decay modes. The first direct tests of the e-{mu}-tau universality of the weak charged couplings at Q/sup 2/=m/sup 2//sub W/ is provided. Measured W and Z/sup 0/ rates and heavy flavour cross sections are used to predict rates of missing transverse energy events from all known Standard Model processes, and thereby to place limits on possible new sources. After taking into account all known sources of missing energy events, we find a mass limit on a fourth generation charged lepton of m/sub L/ > 41 GeV/c/sup 2/ and a limit on the number of additional neutrinos of N/sub {nu}/ < 7. Lower limits for supersymmetric particles, namely 60 GeV/c/sup 2/ for the gluino and 70 GeV/c/sup 2/ for the squark are also given. Finally, two events are presented in which two energetic hadronic jets and a high energy lepton are balanced by missing energy. These events are discussed and compared to all observed W + 2-jet events.

The main physical properties of amorphous systems are examined and an general overview of this subject as a matter of active research is presented. The amorphous systems contain a rich phenomenology without a reasonable explanation up to now and can yield a sort of technological applications, this represents a stimulus for scientists and technologists. (MWO).

A general overview of the main properties of glassy materials is provided. The use of topological methods, gange invariance properties and statistical crystallography is presented in detail. A new step further on the issue of describing and classfying amorphous materials is given. (MWO).

We examine the mechanical properties of covalent random networks with high and low mean coordination. It is shown that networks with high mean coordination (amorphous solids) have elastic constants determined by the covalent forces whereas networks with low mean coordination (polymeric glasses) have elastic constants determined by the longer range molecular forces. These ideas can be made rigorous by considering the number of continuous deformations (i.e. zero frequency modes) allowed within the network. In the transition from one kind of network to another, rigidity percolates through the system. This leads to a picture in which polymeric glasses have large floppy or spongy regions with a few rigid inclusions. On the other hand in amorphous solids, the rigid regions have percolated to form a rigid solid with a few floppy or spongy inclusions.

The aim of this work is to give a summary of the attempts made up to the present in order to discribe by structural models the atomic arrangement in metallic glasses, showing also why the structure factors and atomic distribution functions cannot be always experimentally determined with a reasonable accuracy. (M.W.O.).

We present a review of the principal methods used to prepare metallic alloys in the amorphous phase, focussing on two which have come into widespread use: melt-spinning and sputtering. Methods of characterizing the amorphous state are discussed. Finnaly we discuss briefly a kinetic approach to understanding the formation of mettalic glasses.

We discuss the changes in transport and superconducting properties of amorphous Zr/sub 70/Cu/sub 30/, induced by thermal relaxation. The experimental results are used to investigate the relation between the microscopic parameters and the observed physical properties. It is shown that the density of eletronic states determines the shift Tc as well as the variation of the electrical resistivity. It is necessary to assume strong hybridization between s and d bands to understand the eletrodynamic response of the superconductor.

A general survey on the issue of calculating the electron density of states in metallic glasses is provided. A special emphasis is given to amorphos alloys of transition metals. (MWO).

Real space renormalization techniques are applied to study different disordered systems, with an emphasis on the understanding of the electronic properties of amorphous matter, mainly semiconductors.

The concept of magnetic valence and a generalized Slater-Pauling construction permit a consistent interpretation of the ferromagnetism of both transition metal and metalloid alloys with Fe, Co and Ni. Amorphous alloys like CoB, CoSi, FeB and FeSi are revealed to be strong ferromagnets with a constant number of majority-spin sp electrons over a certain composition range.

The consequences of disorder on magnetic properties of solids are examined. In this context the word 'disorder' is not synonimous of structural amorphicity; chemical disorder can be achieved e.g. by randomly diffusing magnetic atoms on a nonmagnetic crystalline lattice. The name Amorphous Magnetism must be taken in a broad sense.

We briefly review the problem of reentrant ferromagnetism with particular emphais on the controversy between coexistence or reentrant behaviour. We discuss a cluster and a glassy model which are relevant for the understanding of the properties of these materials. We find that for a ferromagnetic instability to occur it is essential the existence of non-colinearity or an anisotropic coupling between spins.

We describe briefly the strong cupling superconductivity observed in amorphous alloys based upon simple metals. For transition metal alloys we discuss the behavior of the superconducting transition temperature Tc, the upper critical field H/sub C2/ and the critical current J/sub C/. A survey of current problems is presented.

The electron density of states of solid solutions of vanadium based transition metal alloys V/sub 90/ X/sub 10/ is computed with the aim of calculating the superconducting transition temperature using the McMillan formula. As observed experimentally for X on the left hand side of V in the periodic table, one obtains an increase of Tc while for X on the right hand side of V the critical temperature decreases. The detailed comparison with experiments indicate that when the bandwidths of the two constituents are different, one cannot neglect the variation of the electron-phonon interactions. Another important conclusion is that for alloys which are in the split-band limit like VAu, VPd and VPt, the agreement with experimental data can be obtained only by assuming that these alloys have a short-range order favouring clusters of pure vanadium.

The main physical properties of amorphous systems are examined and an general overview of this subject as a matter of active research is presented. The amorphous systems contain a rich phenomenology without a reasonable explanation up to now and can yield a sort of technological applications, this represents a stimulus for scientists and technologists. (M.W.O).

We relate the metal-nonmetal transition in expanded liquid mercury to the dieletric transition in dense mercury vapor. We propose that the high-temperature, high-pressure fluid is an excitonic insulator phase. Condensation of Frenkel excitons is shown to occur at the dieletric transition. The phase diagram of excitonic insulator explains naturally both the metal-nonmetal and the dieletric transitions. The permanent dipole moments of the condensed excitons are estimated to order as a ferroelectric phase. The critical exponents of the liquid-gas transition are therefore classical within the ferroelectric excitonic insulator phase, crossing over 3d Ising at the ferroelectric-paraelectric transition. (The authors).

Memory function formalism is briefly reviewed and applied to electronic transport using the projection operator technique. The resistivity of a

disordered 2-D electron gas under strong magnetic field is obtained in terms of force-force correlation function.

A one dimensional alloy model is treated in the nearest neighbour tight binding approximation in which the correlation of the atoms can be adjusted. The correlation can be changed from a situation in which there is a tendency for atoms to alternate to a situation in which the atoms are randomly located, consistent with a fixed concentration c for A /sub c/ B/sub 1-c/. The results show that when there is short range order, at certain energies there is a tendency for localized states and formation of structure induced minimum in the density of states. The results for the ordered case are similar to those of Charge Density Wave (CDW). A smooth transition is carried out between this case and the randomly disordered case which behaves like the Anderson model for uncorrelated disorder. (M.W.O.).

We study the eletronic properties of the disordered linear chain using a technique previously developed by some of the authors for an ordered chain. The equations of motion for the one electron Green function are obtained and the configuration average is done according to the GK scheme. The dynamical problem is transformed, using a renormalization group procedure, into a bidimensional map. The properties of this map are investigated and related to the localization properties of the eletronic system.

The simulation of a hard sphere fluid by a totally random configuration is performed. The relation of the charge distribution of this system and its geometrical configuration is examined. (M.W.O.).

It is developed a simple formalism which allows us to perform a self consistent non-parametrized calculation in a non-periodic system, by finding out the thermodynamically averaged Green's function of a cluster Bethe lattice system.

It is proposed a self-consistent model of first principles for the determination of the electronic structure of deep defects in insulators, which is an improvement of the crystalline aggregate method proposed for the study of perfect crystals. It is shown that, with a proper choice of the aggregate, it reduces to the formal self-consistent solution of the defect problem in the Wannier representation. This procedure is applied with sucess to an U center in NaCl. (M.W.O.).

In this work we describe the impurity bands resulting from the enlargement of the A/sub 1/,T/sub 2/,E and D/sup -/ levels of the donors in Si at intermediary concentrations. These bands are described by a tight-binding Hamiltonian with two base orbitals per site, explicitly including a local Coulombic repulsion. The base orbitals contain both a tetrahedral symmetry as well as a the Bloch's oscilatory factor. The particular case Si:P is explicitly calculated. (M.W.O.).

We investigate the microscopic structure of the impurity states in two-and three-dimensional (2D and 3d) disordered systems. A cluster model is outlined for the donor impurity density of states (DIDS) of doped semiconductors. It is shown that the impurity states are very sensitive to a change in the dimensionality of the system, i.e from 3D to 2D system. It is found that all eigenstates become localized in 2D disordered system for a large range of concentration.

We obtain the density of states for electrons at the inversion layer of a MOS structure due to Na/sup +/ impurities located in the oxide. The impurity potential is assumed unscreened. We take account of disorder to obtain the configurational averaged Green's function starting from a tight binding Hamiltonian.

The lowest order diagram in a perturbative expansion of the force-force correlation function for a 2-D electron gas under strong magnetic field is used to calculate its resistivity.

The r term of the thermoelectric power expression was calculated from experimental data for the electric resistivity of metal alloys in the extension

of Faber-Ziman theory to metallic glasses. With this aim it was employed the scattering matrix formalism and the dependence of the energy of the phase displacements which are contained in it. The results are compared to the experimental data and a deviation with respect to composition is observed, although similarities found in liquid metal alloys. (M.W.O.).

A pulsed NMR study on several transition metal + metalloid amorphous alloys is reported. The analysis of Knight shifts and nuclear spin-lattice relaxation times of metalloids indicates a dominant contribution of p- electrons in the Fermi level density od states, supporting the existence of p-d hibridization.

The electron single particle occupation function for a liquid metal is calculated using the Bardeen's approximation. The results obtained indicate there is no discontinuity in that function at the Fermi level. (M.W.O.).

The low temperature phases of the alkali cyanides KCN and NaCN are investigated. The Isisng Model with incorporation of pair correlations (Bethe approximation) is used to calculate the temperature dependence of the dieletric constant. The parameters of the model are obtained by adjusting its theoretical predictions to experimental values. This parametrization is used to calculate the temperature dependence of the specific heat. Our results are in good agreement with experimental data.

The purpose of this paper is to present a method for the calculation of the absorption coefficient of materials in thin film form using transmission data. The method was applied to the calculation of the absorption bands of a series of samples of hidrogenated silicon nitride. (M.W.O.).

Experimental results on the photoconducticity of amorphous hydrogenated silicon nitride a-SiNx: H prepared from plasma decomposition of a gaseus mixture of silane and nitrogen ([Si H/sub 4/]/[N/sub 2/] {similar_to}0.33) are presented. The material is deposited in a capacitively coupled glow discharge system and nitrogen content was continuously increased by increasing the RF power dissipated in the plasma. Studies of the photocurrent as a function of temperature as a function of temperature and light intensities are reported.

The experimental results of the photoluminescence spectra of intrinsic layers of a: Si: H: F deposited by the electric discharge method are presented. This procedure was developed in the presence of silane. (M.W.O.).

In this paper we report a new theory that reproduces qualitatively well the Raman spectrum of v-B/sub 2/O/sub 3/. The basic idea is that one can find the thermodinamically averaged Green's function for a Bethe lattice, with a Born Hamiltonian, with dihedral angles totally random. In extension one constructs a Bethe lattice of rings and solve the equations of motion for Green's functions at the Boron sites, bridging oxygens and oxygens in the rings. (M.W.O.).

We introduce a model for the lattice dynamics of SI/sub 3/N/sub 4/ in its amorphous phase. This model is based on a Born hamiltonian, solved in the Bethe lattice approximation. We included the local vicinity until third nearest neighbours, building up the central cluster. (M.W.O.).

A specific solid system with first order phase transition in its surface is analysed. To accomplish this task, we use the Landau theory. (M.W.O.).

The effect of vacancies in the concentration properties of a binary alloy A/sub x/ B/sub 1-x/ with random distribution of its atoms is considered. (M.W.O.).

The first Born approximation supposedly inadequate for dealing with elastic scattering of spin polarized electrons on ferromagnets is reconsidered. It is found that when used in conjunction with a spin dependent pseudopotential, it can describe the gross features of the ansisotropy.

In this letter is studied the correlation between magnetism and spatial ordering in the Bethe aproximation for a system with a body centered cttice. (M.W.O.).

It is investigated the effect of adsorbed atoms on the magnetic properties of ferromagnets. The Ising model is employed considering nearest neigbours with antiferromagnetic coupling between atoms. (M.W.O.).

The magnetic properties of translation metal alloys are studied apllying the Hartree-Fock method and the Hubbard Hamiltonian. (M.W.O.).

It is investigated a gel-liquid crystal phase transition employing a two-state model equivalent to the Spin 1/2 Ising Model with applied magnetic field. The model is studied from the standpoint of the cluster variational method of Kikuchi for cooperative phenomena. (M.W.O.).

Using the action at a distance priciple it is derived the total classical action for interacting stationary closed dislocations which reproduces elasticity theory. (M.W.O.).

The total structure factor S(Q) of the Mg/sub 75/ Cu/sub 20/ Sn/sub 5/ amorphous alloy obtained by the 'melt-spinning' tecnique has been measured by means of X-ray diffraction. The magnetic susceptibility was also measured for those temperatures from which the melt was rapidly cooled to obtain the amorphous samples. (M.W.O.).

Using ferromagnetic resonance, it was investigated the crystalization of the METGLAS 2826 and METGLAS 2826A. The line width of the first derivative of the absorption curve was measured for several time intervals o isothermal treatment at 375/sup 0/C. It was observed that after a decrease, due to tension relaxation, the line width increases with the interval of time treatment. The resultus indicate that, for suficiently long in itervals of time. the line width is function of the transformed fractiononly.

It was studied the crystallization of amorphous metallic ribbons of Fe/sub 1-x/ Ni/sub x/ /sub 80/ B/sub 2/0 using the method of isochronous heating at variable slopes. The crystallization temperatures were determined from the transition observed in the electrical resistivity. (M.W.O.).

In this letter, it is reported the construction of a 'melt-spinner' used in the fabrication of amorphous ribbons. For the alloy Fe/sub 80/ B/sub 20/, it is studied the width of the ribbon as a function of the flux of incident material. The results agree with the theoretical model which considers the energy equilibrium on the cooling surface as a dominant factor in the formation of the ribbon.

The Moessbauer spectra of paramagnetic Fe-Zr alloys in several concentrations were studied and it is shown that a certain specific distribution can describe the Fe/sub 25/ Zr/sub 75/ spectrum as well as others authors distributions. (M.W.O.).

The issue of crystallization in polymers and its relation with the glassy temperature Tg and the homogeneous nucleation temperature is investigated (M.W.O.).

The experimental results concerning Nuclear Magnetic Resonance in B/sub 2/O/sub 3/ glasses are presented. The data analysis allows the study of the problem of spectral diffusion in a inhomogeneously enlarged resonance line in a disordered system of nuclear spins. It is proposed a model with the aim of explaining the observed time constants and the peculiar forms of decay. (M.W.O.).

The latent heat and the activation energy measurements in the amorphous-crystal phase transition of the Fe/sub 81/ B/sub 13/,/sub 5/ Si/sub 3/,/sub 5/ C/sub 2/ alloy is presented. (M.W.O.).

We described a high pressure reactive dc-sputtering system for a-Si:H deposition. Optical and electrical transport measurement were performed in order to characterize the films. Results of dark and photoconductivity as a function of temperature and hydrogen content, and optical gap dependence on hydrogen content are present. (M.W.O.).

Preliminary results on deposition and characterization of hydrogenated amorphous silicon thin films are presented. These films were produced by the RF Glow Discharge procedure. The RF power applied and the He:SiH/sub 4/ proportion were varied in the deposition chamber. The increasing rate, the absorption coefficient, the optical gap and the electrical conducivity as a function of temperature were studied. It was verified that inside the studied range, those properties are, with the exception of the increasing rate weakly dependent of the deposition conditions.

Four sets of five films of a-Si:H:N were developed on glass using the RF glow discharge procedure in a sylane and nitrogen (N/sub 2/) atmosphere with several concentrations. The samples were analysed through optical transmission for the determination of the thickness, refraction index, optical gap using a program inserted in a VAX-II system. The films were characterized by electrical conductivity measurement as function of temperature with the aim of determining the activation energy.

Using the glow discharge procedure, hydrogenated amorphous silicon a-Si:H thin production, several temperature and plasma conditions were analysed. (M.W.O.).

It is presented a new technique for the production of amorphous silicon solar cells based on the development of thin films of a-Si in a reactor in which the decomposition of the sylane, induced by capacitively coupled RF, and the film deposition occur in separate chambers. (M.W.O.).

In this paper is investigated the interrelation between macroscopic and microscopic magnetic phenomena using experimental data from Moessbauer effect and the magnetization of layers of amorphous (Fe/sub 1-x/ Ni/sub x/) /sub 80/ B/sub 20/. The Moessbauer effect measurement show a distribution of hyperfine fields in Fe site as well as a likely distribution of isomeric shifts (M.W.O.).

Solid samples of (In/sub 16/ Te/sub 84/)/sub 1-x/ Sn/sub x/ and (Ge/sub 15/ Te/sub 85/)/sub 1-x/ Sn/sub x/ were obtained by means of splat-cooling techniques. The materials was cooled down from different initial temperatures of the liquid state and the samples were analysed by Moessbauer Spectroscopy and X Ray diffraction. (M.W.O.).

This thesis contains three sections discussing different areas. Spin wave interactions in iron garnets are described in section one. Mathematical analysis of a magnetic oscillator is presented in section two. In the final section, the source of noise in Josephson Junctions is investigated. The three sections are indexed separately. (JDH)

An experimental study is made of the interactions between spin wave modes excited in a sphere of yttrium iron garnet by pumping the Suhl subsidiary absorption with microwaves. The dynamical behavior of the magnetization is observed under high resolution by varying the dc field and microwave pump power. Varied behavior is found: (1) onset of the Suhl instability by excitation of a single spin wave mode; (2) when two or more modes are excited, interactions lead to auto-oscillations displaying period-doubling to chaos; (3) quasiperiodicity, locking, and chaos occur when three or more modes are excited; (4) abrupt transition to wide band power spectra (i.e., turbulence), with hysteresis; (5) irregular relaxation oscillations and aperiodic spiking behavior. A theoretical model is developed using the plane wave approximation obtaining the lowest order nonlinear interaction terms between the excited modes. Extension of this analysis to the true spherical spin-modes is discussed. Bifurcation behavior is examined, and dynamical behavior is numerically computed and compared to the experimental data. A theory is developed regarding the nature of the experimentally observed relaxation oscillations and spiking behavior based on the interaction of "weak" and "strong" modes, and this is demonstrated in the numerical simulations for two modes. Quasiperiodicity is shown to occur in the numerical study when at least 3 modes are excited with appropriate parameter values. A possible mechanism for generating microwave subharmonics at half of the pumping frequency is discussed. 57 refs., 25 figs., 5 tabs.

This is an experimental study of a forced symmetric oscillator containing a saturable inductor with magnetic hysteresis. It displays a Hopf bifurcation to quasiperiodicity, entrainment horns, and chaos. The bifurcations and hysteresis occurring near points of resonance (particularly "strong resonance") are studied in detail and it is shown how the observed behavior can be understood using Arnold's theory. Much of the behavior relating to the entrainment horns is explored: period doubling and symmetry breaking bifurcations; homoclinic bifurcations; and crises and other bifurcations taking place at the horn boundaries. Important features of the behavior related to symmetry properties of the oscillator are studied and explained through the concept of a half-cycle map. The system is shown to exhibit a Hopf bifurcation from a phase-locked state to periodic "islands," similar to those found in Hamiltonian systems. An initialization technique is used to observe the manifolds of saddle orbits and other hidden structure. An unusual differential equation model is developed which is irreversible and generates a noninvertible Poincare map of the plane. Noninvertibility of this planar map has important effects on the behavior observed. The Poincare map may also be approximated through experimental measurements, resulting in a planar map with parameter dependence. This model gives good correspondence with the system in a region of the parameter space. 31 refs., 36 figs., 1 tab.

This part takes a new look at an old problem, namely the observed "noise rise" in superconducting Josephson junction parametric amplifiers. By exploiting recent insights from dynamical systems theory, it is shown how the interplay of random noise and (nonchaotic) deterministic dynamics can result in a noise rise like that observed in experiments. This analysis leads to a universal first order equation which applies to all similar systems in the high-gain regime. Several predictions are proposed which can be tested experimentally, including that a similar noise rise should occur in modulated semiconductor injection lasers. An analysis is also made of a previously unknown mode of operation - a "six-photon" mode associated with a symmetry breaking bifurcation - and its potential advantages over the previously studied three-photon and four-photon modes are discussed. 40 refs., 15 figs.

Thin refractory coatings have been demonstrated to deter solid particle erosion. A detailed examination of the microstructures of 10%Ni + TiB{sub 2} with varying sputtering parameters was undertaken by the use of transmission electron microscopy. Advanced instrumentation was then used to determine the micromechanical and macromechanical properties of these coatings. Microstructures, nanoindentation hardness values and moduli of elasticity were compared to obtain a better understanding of the role of sputtering parameters in determining coating performance. 14 refs., 8 figs., 2 tabs.

Recent developments in the design of crystal diffraction lenses has made it possible to build a gamma-ray telescope that produces a real image of a distant object. This can be done both with surface diffraction optics and with transmission diffraction optics. The mathematical solution to both cases is the same but they differ in the way the crystals are cut and bent. Until recently, there was no solution for the transmission case. It is this last case that will be highlighted in this paper, because it is new and because it makes much more efficient use of the crystal material when high energy photons (>50 keV) are being focused. 5 refs., 8 figs.

The diverse variations of the conductivities vs. temperature observed in oxide superconductors can be interpreted with a model based on microcanonical ensembles of a semiconductor and a semimetal originally derived for organic radical cation salts. The equation for the model transverses, through the variations of the Fermi and gap energies and a scattering factor, the range from a semiconductor to a semimetal and defines quantitatively the boundary between the two corresponding to the optimum superconducting state. Therein it describes quantitatively the roles of composition and pressure in determining the onset of the superconducting state. An examination of the published resistivity curves vs. temperature for La/sub 2-x/A/sub x/CuO/sub 4-{delta} and YBa{sub 2}Cu{sub

3}O/sub 6.5 + {delta} yield information consistent with the model and relevant to the defects and range of homogeneity needed for phase diagrams. 5 figs., 22 refs.

We have studied the effects of virtual Cu-O charge fluctuations in the perovskite high-T/sub c/ materials by applying a strong coupling expansion to an extended Hubbard model with hybridized Cu d-orbitals and O p-orbitals. Results for charge fluctuation-mediated site-diagonal effective interactions are discussed. 6 refs.

The purpose of this report is to develop the kinematic basis for a theory of deformation of materials with defects. One specific objective is to derive clear concepts of strain, strain-rate, stress and stress rate, and to demonstrate some new relations between measures of these quantities. A related objective is to clarify the concepts of strain, strain rate and stretching, so that the principle of superposition of strain rates can be developed in a systematic way in subsequent reports. This principle allows us to compute deformations involving both plastic flow and fragmentation. The theory of large deformation is addressed in a systematic manner with the polar decomposition theorem as a starting point. Two sets of orthogonal axes are distinguished, space axes that are fixed in ambient space, and polar axes that are related to material deformation. It is shown that in elasticity, Piola stress is a measure in polar axes. In addition, a special approach to computing rates of tensor quantities, called polar rates, is derived from several viewpoints. This allows us to compute rates in a manner that accounts for material rotation in an exact way. One consequence of this is a simple relation between Signorini strain rate and stretching, the symmetric part of the velocity gradient. A second result is to show that the polar stress rate is the appropriate measure of rate of change of Cauchy stress, and that the more traditional stress rate of Zaremba, Jaumann, and Noll is only an approximation, valid at small strains. Examples are described for materials undergoing simple shear, vortex motion and torsion. 20 refs., 10 figs.

This research was undertaken to determine if the AWC TRUclean process could remove radioactive contamination from differing soil matrices that were submitted by participating sites from around the nation. The TRUclean process removed plutonium from coral derived soil. Interest developed in applying the process to other radioactive contaminants and soil types. Soils from the Nevada Test Site (NTS); Rocky Flats Plant (RFP) in Colorado; FUSRAP site at Hazelwood, Missouri; Monsanto-Mound site in Ohio, and the Ft. Dix site in New Jersey were tested. The TRUclean process was able to effectively decontaminate soils and concentrate the contamination into a substantially smaller volume than the original soil. 14 refs., 6 figs.

Compositional changes of weld metal from welds made by submerged arc flux welding of steel using CaF{sub 2}-CaO-SiO{sub 2} fluxes are consistent with an electrochemical mechanism in which the filler wire is anodically oxidized to form oxides and fluorides, and metals are cathodically deposited at the weld pool-flux interface. This speculative mechanism, if proven by further detailed studies, could make it possible to predict fluxes which will improve the quality of welds. 10 refs., 3 figs., 3 tabs.

This booklet contains answers to frequently asked questions about high-level nuclear wastes. Written for the layperson, the document contains basic information on the hazards of radiation, the Nuclear Waste Management Program, the proposed geologic repository, the proposed monitored retrievable storage facility, risk assessment, and public participation in the program. (TEM)

Deontamination and decommissioning of retired nuclear power reactors is a necessary part of the nuclear fuel cycle. Inventories of radioactivity that will be encountered at large facilities (500 to 1200 MWe) during decommissioning operations include activated reactor components and contaminated piping, equipment, and building surfaces. Contaminated areas of the facility result from processing the primary coolant that contains activation products and fission

products from the reactor core. The most abundant radionuclides in the inventory include {sup 58}Co, {sup 60}Co, {sup 55}Fe, {sup 59}Fe, {sup 51}Cr, {sup 59}Ni, and {sup 63}Ni. Because of the relatively short physical half-lives of most activation products, the decision of when to decommission a reactor will directly influence the magnitude of the collective dose estimate. The total collective dose is the sum of exposures to several groups of individuals. These groups include decommissioning workers, transportation workers, the population along major transport routes, and the population living in the vicinity of the decommissioned reactor. Previous generic studies of the potential, collective radiationdoses from decommissioning have concluded that, barring accidents, the group receiving the most significant radiation doses will be the workers performing the decommissioning. This paper reviews generic population dose estimates for decommissioning reference boiling water and pressurized water reactors and provides extrapolated estimates of the total collective dose resulting from decommissioning the commerical nuclear reactors that have operated to date in the United States.

This report describes the work performed to investigate filtration improvement techniques applied to an existing filtration system installed at TMI-2 to maintain water clarity for on-going defueling activities on the damaged reactor. The investigation included laboratory and full-scale testing of organic and inorganic coagulant aids and of various precoat and body feed materials singly or in combination with coagulant aids. 33 figs., 21 tabs.

This paper builds a framework for addressing how ORNL might increase its contribution to US competitiveness. It begins with an analysis of the changing nature of international commercial competition. The goal in the first part of the paper is to provide a picture of why US competitiveness has eroded and what is required if the nation is to be competitive. The latter portion of the paper investigates actions which might be taken to enhance the Lab's potential for contributing to commercially competitive innovations.

Eleven wide-plate crack-arrest tests have been completed to date, seven utilizing specimens fabricated from A533B class 1 material (WP-1 series), and four fabricated from a low upper-shelf base material (WP-2 series). With the exception of one test in the WP-1 series and two tests in the WP-2 series which utilized 152-mm-thick specimens, each test utilized a single-edge notched (SEN) plate specimen 1 by 1 by 0.1 m that was subjected to a linear thermal gradient along the plane of crack propagation. Test results exhibit an increase in crack-arrest toughness with temperature, with the rate of increase becoming greater as the temperature increases. When the wide-plate test results are combined with other large-specimen results (Japanese ESSO, thermal-shock experiments and pressurized-thermal-shock experiments), the data show a consistent trend in which the K/sub Ia/ data extends above the limit provided in ASME Section XI.

This paper contains viewgraphs on the topic of radiation effects of solid state materials. In particular, it elaborates on ion beam deposition of thin film structures, ion implantation damage in crystals of Al{sub 2}O{sub 3}, and ion implanted optical waveguides in LiNbO{sub 3}. (LSP)

This report documents the results of Phase II of a three phase research program to develop and validate improved methods to model the cognitive behavior of nuclear power plant (NPP) personnel. In Phase II a dynamic simulation capability for modeling how people form intentions to act in NPP emergency situations was developed based on techniques from artificial intelligence. This modeling tool, Cognitive Environment Simulation or CES, simulates the cognitive processes that determine situation assessment and intention formation. It can be used to investigate analytically what situations and factors lead to intention failures, what actions follow from intention failures (e.g., errors of omission, errors of commission, common mode errors), the ability to recover from errors or additional machine failures, and the effects of changes in the NPP person-machine system. The Cognitive Reliability Assessment Technique (or CREATE) was also developed in Phase II to specify how CES can be used to enhance the

measurement of the human contribution to risk in probabilistic risk assessment (PRA) studies. 43 refs., 20 figs., 1 tab.

In the past few years the methods of radiation chemistry in organic media have made an enormous change in how we view electron transfer processes, as these media have proved the most useful for studying long distance electron transfer between molecules. This paper briefly summarizes a few of the aspects of this area and discusses some of the attributes and limitations of radiation tehniques, particularly pulse radiolysis, in organic solvents. 14 refs., 2 figs.

The nonlinear evolution of the internal kink mode is studied in toroidal geometry for noncircular cross section tokamak plasmas. The study is focused on very low shear and hollow q profiles with q(rho) {ge}1 for which the internal kink is unstable, in the latter case even at {beta}- 0. The nonlinear evolution is dominated by ideal magnetohydrodynamics (MHD), and the instability saturates, giving a quasi-helical shift to the magnetic axis. The nonlinear saturation is caused by increased field line bending. Time scales of 10{sup 3} tau/sub Hp/ and axis shifts of 20% are reached when changes in q on the order of 3 x 10{sup -3} from the marginal profile are produced. 25 refs., 27 figs.

System studies of next-generation superconducting tokamaks are presented here. These studies include examining design changes suggested for the International Tokamak Reactor (INTOR) as a means of reducing the size and simplifying the device and assessing the impact of a series of more aggressive design assumptions suggested in recent Engineering Test Reactor (ETR) studies. Also, a set of candidate design points offering small machines (major radius = 4 m) with a relatively conservative mix of design assumptions is proposed. Some of the design assumptions found to have a major effect on the minimum size are TF coil current density, noninductive current drive, plasma elongation and edge q, plasma temperature for current drive, maximum allowable plasma beta, the minimum required wall load, and assumptions on fixed radial dimensions such as shield thickness, gaps, and plasma scrapeoff. Some design assumptions with less impact on the device size are the OH coil current density, PF configuration (limiter/divertor), and plasma current level. 22 refs., 5 figs., 6 tabs.

Corrosion data are presented for several vanadium alloys exposed to flowing lithium at 427, 482, and 538{sup 0}C. The corrosion behavior is evaluated by weight change measurements. Metallographic results and data on the nonmetallic element transfer in lithium-exposed specimens are also presented. The influence of alloy composition and exposure conditions on the corrosion behavior of vanadium alloys is discussed. 6 refs., 9 figs., 2 tabs.

Ceramic materials are under investigation as potential breeder material in fusion reactors. This paper will review candidate materials with respect to fabrication routes and characterization, properties in as-fabricated and irradiated condition, and experimental results from laboratory and inpile investigations on tritium transport and release. Also discussed are the resources of beryllium, which is being considered as a neutron multiplier. The comparison of ceramic properties that is attempted here aims at the identification of the most-promising material for use in a tritium breeding blanket. 82 refs., 12 figs., 5 tabs.

The production and distribution of Californium-252 in USA has recently been consolidated at ORNL. This document consists of viewgraphs and comments. (DLC)

The oxidation of Mo(100) and Ba-covered Mo(100) by O{sub 2} have been examined at moderately high temperature (700 to 1400{sup 0}K) using x-ray photoelectron spectroscopy. Results indicate that the Ba or BaO overlayer retards but does not prevent oxidation of the underlying Mo surface. The high temperature surface chemistry of the O/Ba/Mo surface is described. 11 refs., 3 figs.

This paper covers Industrial Hygiene involvement in the Site Characterization Program, focusing on the field oversight responsibilities. It discusses the different types and levels of protective equipment, gives an example of the type

of situation that can arise from field characterization efforts, and gives a brief summary of health protection program elements. 3 figs., 3 tabs.

Since the publication of Mantel and Haenszel's pioneering paper in 1959, has seen a veritable explosion of statistical methodology in chronic disease epidemiology. The central methodologic issues revolve around environmental and genetic risk assessment, and risk extrapolation. The tenth Research Application Conference held under the auspices of SIMS brought together experts from around the world to discuss the theory and applications of statistical methods in chronic disease epidemiology. This volume represents the proceedings of that conference. Relative risk regression models provide flexible and powerful tools for the analysis of epidemiologic data. These models have been the objects of intense study in the past several years, and it seems reasonable to predict that relative risk regression methods will become a, or perhaps, the, central analytical tool in chronic disease epidemiology. Thus, a major emphasis of the conference was on relative risk regression, and various papers in this volume deal with time-dependent covariates, new study designs, multivariate failure time data, methods of model criticism, parameter transformations for optimal inference, and issues in matching, covariate adjustment, and incomplete and missing covariate information.

This paper documents and codifies a data base that consists of extensive laser-based measurements of velocity and density in a turbulent nonpremixed flame of hydrogen in air. These data were obtained in the Turbulent Combustion Tunnel Facility located at the Combustion Research Facility of Sandia National Laboratories. In these flames, the chemical reaction rates for the major species are greater than the mixing rates and, therefore, the data reported here can be used for improvement of models of turbulent mixing with large heat release without the additional complication of finite rate chemical kinetics. As an example of model improvement, comparisons of the data base with predictions of a numerical model of turbulent reacting flow are made.

In this paper we describe our studies of ceramic samples of La{sub 2}CuO/sub 4-y/ loaded with oxygen by high pressure. This technique results in substantial incorporation of O{sub 2} in the material (of the order of 0.3 to 0.4% by weight) and in gross changes in the bulk resistivity and magnetization as well as discernible changes in the lattice parameters of the material. 7 refs., 2 figs.

Metallic superlattices exhibit a correlation between the epitaxial growth temperature and temperatures extracted from the equilibrium thermodynamic phase diagram. This correlation together with molecular dynamics simulation of epitaxial growth indicates that thermodynamics plays an important role in the growth of epitaxial films, particularly in limiting the sharpness of the interfaces.

The isothermal drying of an initially saturated welded tuffaceous rock was studied experimentally. Gamma-beam densitometry was used to measure the material's effective porosity distribution prior to the drying experiment. It was then used to measure liquid saturation distributions during a 1400 hour drying period. The core selected for study was taken from the Busted Butte outcrop at the Nevada Test Site, part of the Topopah Spring Member of Paintbrush tuff. This specimen contained several microfractures transversely oriented to the direction of the water or vapor migration. These fractures were found to be regions of rapid dryout or low saturation even though they were displaced from the surface over which dry nitrogen was flowing. An imbibition experiment was performed earlier on the same core. In the imbibition experiment the presence of most of these microfractures was detected by discontinuities in the measured saturation curves, which indicated a delay in liquid transport past the microfractures. The mechanism for this inside out drying is believed to be capillary action that removes water from the larger-pore fracture zone. Vapor pressure lowering in the fine pore region, which would result in transport by evaporation, diffusion and condensation, is thought not to be important at room temperatures. Modeling of this dryout experiment reproduced some of the overall

features of the experiment but underpredicted the saturation near the drying surfaces. 8 refs., 11 figs.

This report is intended to provide a summary of the cost and schedule performance for the civilian radioactive waste management program. Performance data are presented for each of the major program elements. Also included is the status of the Nuclear Waste Fund revenues and disbursements. 22 figs.

New data are presented for the level structures of {sup 143}Ba, {sup 147}Ce, {sup 147}Pr, {sup 143}Cs, {sup 132}Sb, {sup 130}Sb, {sup 129}Sb, {sup 129}Te, and {sup 132}Te. New conversion electron and gamma-ray coincidence measurements are reported for the even-even {sup 118}Xe, {sup 120}Xe, {sup 122}Xe, {sup 124}Xe nuclides which include the identification of a number of new E0 transitions. New values for the magnetic moments in {sup 77}Br, {sup 75}Br, and {sup 74}Br are presented. The results for each of these nuclides are discussed.

After summarizing the development of a model that describes the induction heating process in axisymmetric geometries and the implementation of the model in the FIDAP code, it is applied to a particular process that is being used at the Lawrence Livermore National Laboratory in conjunction with advanced crystal growth technology for the laser program. 11 refs., 43 figs., 1 tab.

The content of this paper is divided into two parts: (1) achievements of the last two years in studying molecular ion structure with the aid of the newly developed Coulomb-Explosion (CE) method, and (2) the understanding of the modern CE data in terms of an invariant density of nuclear coordinates of the studied molecule.

Native vegetation associated with commercial low-level waste disposal sites has the potential for modifying the soil chemical environment over the long term and, consequently, the mobility of radionuclides. These effects were assessed for coniferous and hardwood tree species by using plants grown in lysimeter systems and examining their influence on soil solution chemistry using advanced analytical and geochemical modeling techniques. The study demonstrated formation of highly mobile anionic radionuclide complexes with amino acids, peptides, and organic acids originating from plant leaf litter and roots. The production of complexing agents was related to season and tree species, suggesting that vegetation management and exclusion may be appropriate after a site is closed. This research provides a basis for focusing on key complexing agents in future studies to measure critical affinity constants and to incorporate this information into mathematical models describing biological effects on radionuclide mobility. 26 refs., 5 figs., 23 tabs.

Mixtures of crushed rock and bentonite are considered for backfilling and sealing high-level nuclear waste repositories. Many variables affect the hydraulic conductivity of such mixtures, including the size and shape of the rock particles, method of mixing and emplacement, water content and density of the clay, and the weight ratio of rock to clay. Mixtures of crushed basalt and bentonite have been tested in two types of permeameters, 20 cm diameter stainless steel permeameters and 10 cm diameter PVC permeameters. Plugs were installed as a single lift or in many lifts; the water content of the clay ranged from air-dry to as high as 200%. Preliminary results show that a mixture of 75% crushed basalt and 25% bentonite has a hydraulic conductivity between 1 x 10{sup -9} cm/s and 2.5 x 10{sup -8} cm/s. In some cases, preferential flow paths have developed (possibly as a result of the montmorillonite washing out of the crushed rock matrix), giving hydraulic conductivities as high as 1 x 10{sup -4} cm/s. Other ratios of rock to clay have similar bimodal results. The probability of failure is decreased by including a higher percentage of clay in the plug, crushing the rock finer, and evenly mixing the crushed rock and clay. 136 refs., 50 figs., 7 tabs.

The scope of this volume 28, No. 3 includes the analysis and control of hazards associated with nuclear energy, operations involving fissionable materials, and the products of nuclear fission and their effects on the environment. Primary

emphasis is on safety in reactor design, construction, and operation; however, the safety aspects of the entire fuel cycle, including fuel fabrication, spent-fuel processing, nuclear waste disposal, handling of radioisotopes, and environmental effects of these operations, are also treated. Fourteen articles have been cataloged separately.

This article summarizes the development, design, and operation of the Soviet accident localization system (ALS) and assesses the ALS design objectives and capabilities as applied to the Chernobyl Atomic Energy Station Unit 4 (Chernobyl-4) RBMK-1000 reactor. Because the purpose of the ALS is to provide a barrier against the uncontrolled release of radioactive material to the environment during certain reactor-cooling-system pipe breaks, the ALS has been described as the Soviet RBMK-1000 counterpart of commercial US light-water-reactor (LWR) containments. Assessment of the ALS capabilities from this perspective is included through a general description of the design objectives and typical features of commercial US LWR containments. A hypothetical RBMK-1000 containment incorporating typical design features of commercial US LWR containments is studied in a scoping assessment for performance under conditions estimated to be similar to those imposed by the Apr. 26, 1986, accident at Chernobyl-4. 3 refs., 7 figs.

During the week of Oct. 20-23, 1986, nuclear power-plant safety representatives from the Federal Republic of Germany (FRG), France, Japan, and the US assembled to discuss subjects of mutual interest. The meeting, the first of its kind, was organized under the leadership and direction of David A. Ward, Chairman, Advisory Committee on Reactor Safeguards, US Nuclear Regulatory Commission (NRC), and held at the Wingspread Conference Center of the Johnson Foundation in Racine, Wis. Approximately 40 representatives of the several countries attended. Discussions were candid and provided the participants an opportunity to share thoughts and information on nuclear safety concerns and solutions.

This article provides a brief review of the Fourteenth Water Reactor Safety Information Meeting, one of an ongoing series of meetings sponsored by the Nuclear Regulatory Commission (NRC), Office of Nuclear Regulatory Research, to give the nuclear safety community up-to-date information on NRC-sponsored and other research in the nuclear safety area. 2 refs., 1 tab.

The two worst accidents in the world's nuclear industry occurred in a time span of seven years, namely, the accidents at Three Mile Island Nuclear Station Unit 2 (TMI-2) in 1979 and at Chernobyl in 1986. Because probabilistic risk assessments (PRAs) have been shown to be effective in identifying weak points in plant design and operations, they can help prevent or mitigate future reactor accidents. For the improvement of their effectiveness, two important technical issues need to be addressed: the capability to update PRAs frequently and the proper design objective for measuring plant safety performance. 1 fig.

This article outlines the development of two different tritium-monitoring strategies. Some CANDU power stations rely on multiplexed, centralized tritium monitors whereas the new Darlington station utilizes many simple distributed monitors. The article compares tritium-monitoring requirements at tritium-removal plants and at fusion facilities. A major distinction in contrast with fission reactors is the possible need for tritium monitors that can differentiate between tritiated water vapor and tritium gas. The particularly severe monitoring environment around fusion reactors resulting from air activation products, intense neutron fields, and electromagnetic fields must also be considered. Tritium monitoring around fission reactors is difficult because the environment may contain other radioactive gases and radiation fields. The experience gained may be very valuable in solving the even more difficult tritium-monitoring problems of fusion reactors. 27 refs.

Evaluation, testing, and use of fixed-position, remotely operated video-camera equipment and various teleoperators at Three Mile Island Nuclear Station Unit 2 (TMI-2) have demonstrated that significant potential advantages may be obtained by installing remotely operated equipment at other nuclear facilities.

Teleoperators at TMI-2 have permitted successful operations in areas not accessible to personnel. Insights gained from the remotely operated camera systems and teleoperators used and evaluated at TMI-2 are discussed from the perspective of actual applications and the potential benefits from deployment of remote devices at other nuclear facilities. Actual exposure savings achieved are not presented because these applications and resultant exposure savings are specific to TMI-2. 3 refs., 4 figs.

Conference was held Aug. 18-21, 1986, in Seattle, Washington. Major topics discussed during the conference were accident analyses, including fires and explosions; iodine retention on activated carbon, zeolites, and other sorbent media; particulate filtration; treatment of off-gases from chemical- and fuel-reprocessing systems; noble gas retention; laboratory and in-place testing techniques; and the development of standards and regulations. The conference showed that recent air-cleaning research appears to be directed primarily toward the analysis and critique of existing systems; operational assessment and the potential impact of new source terms are in the forefront. European researchers continue to stress air-cleaning problems associated with spent-fuel reprocessing; US concerns, however, are more in the areas of fire detection, prevention, and elimination and in the operation of control-room habitability systems. 11 refs., 1 tab.

The rates at which nuclides contained in high-level wastes are released into solution may be controlled by chemical kinetics, equilibrium solubilities, or solid-state diffusion. Recent research has focused on equilibrium solubility as a relatively predictable factor that in many situations can be expected to hold release rates to low levels. Simple analytic solutions based on equilibrium solubility are available to describe dissolution in various physical situations. For more soluble elements, chemical kinetics may need to be invoked if low release rates must be demonstrated. 47 refs., 2 figs.

A review of the performance of steam generator tubes in water-cooled nuclear power reactors showed that tubes were plugged at 47 (35.6%) of the reactors in 1983 and at 63 (42.6%) of the reactors during 1984. In 1983 and 1984, 3291 and 3335 tubes, respectively, were removed from service - about the same as in 1982. The leading causes assigned to tube failure were stress corrosion cracking from the primary side and stress corrosion cracking or intergranular attack from the secondary side. In addition, 5668 tubes were repaired for further service by installation of internal sleeves. Most of these were believed to have deteriorated by one of the preceding mechanisms or by pitting. A trend continues toward high-integrity condenser tube materials at sites cooled by brackish water or seawater. 31 refs., 3 figs., 12 tabs.

This section presents a regular report of summary statistics relating to recent reactor shutdown experience. The information includes both numbers of events and rates of occurrence. It was compiled from data about operating events entered into the SCSS data system by the Nuclear Operations Analysis Center at the Oak Ridge National Laboratory, covering the three-month period of January, February, and March 1987. Cumulative information, since May 1, 1984, is also shown. Updates on shutdown events included in earlier reports are excluded. 3 tabs.

This update, which appears regularly in each issue of Nuclear Safety, surveys the operations of those power reactors in the US which have been issued operating licenses. Table 1 shows the number of such reactors and their net capacities as of March 31, 1987, the end of the three-month period covered in this report. Table 2 lists the unit capacity and forced outage rate for each licensed reactor for each of the three months (January, February, and March 1987) covered in this report and the cumulative values of these parameters since the beginning of commercial operation. 24 refs., 2 tabs.

"General Administrative Activities" summarizes selected current topics that are related to nuclear safety but do not fit elsewhere in the journal. Included in this report are items reported during January, February, and March 1987. Subjects discussed, among others, are an NRC proposal to modify the emergency

evacuation plan requirement where state and local governments are uncooperative, Advisory Committee on Reactor Safeguards (ACRS) comments on future LWR designs, and several legislative initiatives relating to nuclear safety. 8 refs.

This article contains four lists of various documents relevant to nuclear safety as compiled by the editor. These lists are: (1) reactor operations-related reports of US origin, (2) other books and reports, (3) regulatory guides, and (4) nuclear standards. Each list contains the documents in its category which were published (or became available) during the three-month period (January, February, and March 1987) covered by this issue of Nuclear Safety. The availability and cost of the documents are noted in most instances.

Recent regulatory and other actions relating to US power reactors undergoing these steps toward licensing are summarized in this paper for the first quarter of 1987. This section also contains brief reports of regulatory actions and other significant events relating to reactor projects in the licensing stage that were received during the period covered by this report, namely, the first quarter of 1987. 5 refs., 1 tab.

Separate abstracts were prepared for 14 papers in these conference proceedings. (LEW)

This book is the first in a series of publications containing statistical information and analyses on the wind energy industry. The book is set up in six sections. Section 1 is an introduction and description. Section 2 is an overview of wind energy markets and market trends based on the collected statistical data. As with the book itself, this overview is not an all-inclusive review of the wind industry but rather a focused packet of information on wind turbine manufacturers, turbine shipments, overall turbine characteristics, etc. Section 3 provides statistics on the overall wind turbine market by region, with eight regions making up the world. The data are provided for the 1981-1986 period. Section 4 cross-cuts the statistics by rotor diameter. As the report discusses, rotor diameter appears to provide a more consistent frame of reference than nameplate rating, wind speed performance, or other similar characteristics. Section 5 breaks down the statistics by nine applications, ranging from water heating and water pumping to grid-connected windfarms. Section 6 catalogs wind turbine manufacturing and export/import activity. Supporting statistics are provided at the end of Sections 3, 4, 5, and 6. An appendix provides detailed descriptions of the approximately 150 active wind turbine manufacturers worldwide and their wind turbines.

Individual abstracts are processed separately for the database. (CBS)

The "mixing rule" has been tested using published hydrogen/propane mixture combustion data. Results show a good correlation between the observed data and the predictions made by the "mixing rule." Stability loop data for coal volatiles is also reported. An attempt will be made to correlate the coal volatiles data with the kinetics derived for the "mixing rule." 15 refs., 18 figs., 6 tabs.

The objectives of this project are to develop a method of determining the operational or 'global' kinetics of combustion of volatiles from heated coal, and to compare the reaction rates (kinetic constants) for different coals to establish whether the kinetic behavior is rank sensitive or rank insensitive. The data are important for modeling the burning behavior of the volatiles. 6 refs., 3 figs., 1 tab.

The objective was to develop a char rate equation (sub-model) that is sufficiently elementary that it is tractable in complex flame models, but that is sufficiently complete that it incorporates such necessary and sufficient elements of the chemistry and physics involved in the char combustion (such as boundary layer diffusion, internal reaction, adsorption, and desorption of the reacting species) that combustion rates in flames can be calculated in flame models with required accuracy. 13 refs.

The objective of this project is to obtain chemical kinetic data and to physically characterize chars from PSOC 1451 (bituminous-hvab) and PSOC 1443 (lignite) coals. 6 refs., 7 figs., 1 tab.

The atom probe field-ion microscope can be used to obtain atomic scale microanalysis of metals and alloys, permitting studies of surface regions, interface segregation and the early stages of phase decomposition. With the newer pulsed laser atom probe, these capabilities are extended to the analysis of semi-conducting materials. The increased use of microcomputers to provide on-line computing has allowed automation of the data acquisition process, and also permits the use of statistical data analysis techniques which are invaluable for certain atom probe studies. This paper describes the technique of atom probe microanalysis and reviews some selected applications in both metallurgical and semiconductor studies. 61 refs.

A brief description of the ion implantation process is followed by a review of friction, wear, fatigue, oxidation and corrosion research, with an emphasis on friction and wear studies. Examples are presented of field studies which are generally optimistic about commercial application. This is especially true in areas where increases in lifetime can produce significant savings by reducing the cost of replacement or down time. 54 refs.

During 1981, a 600 metre long section of seam was driven by blasting mining in the anchor mesh wire mining system. There is a description of the conditions for anchor mining, the machines required for blasting mining, the extension, the blasting work, the course of the work and the results of anchor tensile experiments, a comparison of costs between anchor mining and comparable arch mining.

The Welbeck Scheme near Wakefield, West Yorkshire, combines land reclamation with the co-disposal of colliery spoil and controlled (mainly household) wastes. It plans to do so on a grand scale, over an extensive area, and for a long duration; by late 1985 the UK Department of the Environment had committed 1.5 million pounds to the scheme. The subsidiary aims of the scheme are set out, and background to the area is given, particularly the despoilation which has occurred since the Second World War. Levels of integration existing in the Welbeck Scheme, such as the advantages of scale, duration, shared facilities, and physical integration, the economic rationale, and technical or subsidiary levels of integration are considered. Finally, the lessons learnt from implementation of resource and environmental integration are examined. 6 refs.

This article investigates the chemical, mineralogical and particle-size composition of tailings from two Hunosa-operated coal washeries (Spain). The two washeries in question were selected by reason of the size of their output and representativeness. Describes the tests on washery samples which were carried out on the basis of specifications for road and bridge building (P G-3/75). The results obtained indicate that the tailings are eminently suitable for use as fill material. 3 refs., 3 figs., 2 tabs.

Lignite resources are given as 4 x 10{sup 9} t. Their ash composition, moisture, sulphur and chlorine contents and their uses are discussed.

In the immediate vicinity of Santofirme, 16 km south-east of Oviedo, there is an 18 km{sup 2} outcrop of material from the Carboniferous period which forms a syncline running north-east to south-west and which, in places, is covered with Permo-Triassic and Tertiary material from the Depresion de Llanera. The series consists of regularly alternating layers of lutite and sandstone with bands of coal and a few lime bands in the lower section. Twenty-one of the coal bands, grouped together in eight packets, are worked by Minas de Villabona SA. All the coal bands in the western flank of the syncline have been tested. Most of the samples were collected from four drillings carried out by ENADIMSA in 1982; those remaining were taken from the surface at the Arroyo Socavon and La Tejera opencast sites.

The present note summarises recent work in the area of Santa Olaja de la Varga, where post-Asturian Stephanian A is in contact with post-Leonian lower Cantabrian. The stratigraphy of the Sabero Coalfield west of the River Esla has been described and its sedimentary environment has also been further discussed. The Sabero succession is largely of Stephanian B age, with late Stephanian A being recognised in the lower part; it is post-Asturian folding phase and unconformable on lower palaeozoic strata. Recent work has extended the mapping of this post-Asturian succession eastwards across the River Esla into the area near to the villages of Santa Olaja de la Varga and Fuentes de Penacorada. This has resolved the contentious problem of the relationship between the post-Asturian Sabero succession and the post-Leonian folding phase succession of largely Cantabrian strata known in the area of Ocejo de la Pena and in the Valderrueda Coalfield. A clearly unconformable relationship occurs between the pre-Asturian and post-Asturian successions, which is confirmed by sedimentary differences and by fossil floras. 13 refs., 2 figs.

The author discusses the 1975 veto of surface mining legislation and the Surface Mining Control and Reclamation Act of 1977 which has had controversial response. The article discusses some aspects of this controversy and future prospects.

The article discusses the Surface Mining Control and Reclamation Act (SMCRA), the circumstances under which the legislation was enacted during the 1970s, and its passage through congress. The author discusses the possibilities for legislative changes, but states that it does not seem likely that there will be a major overhaul of SMCRA during this congress.

The author states the consequences of the US Surface Mining Act, in terms of mining performance standards and the compliance of the operators, plus the benefits to the environment. The author then discusses the recent congressional votes which have eliminated the two-acre exemption. The rest of the article discusses the need to maintain surface mining.

Although the Soviet Union has more submarines than the NATO navies combined, and the technological superiority of western submarines is diminishing, there is evidence that there are more accidents with Soviet submarines than with western submarine fleets. Whether this is due to inadequate crews or lower standards of maintenance and overhaul procedures is discussed. In particular, it is suggested that since the introduction of nuclear powered submarines, the Soviet submarine safety record has deteriorated. Information on Soviet submarine accidents is difficult to come by, but a list of some 23 accidents, mostly in nuclear submarines, between 1966 and 1986, has been compiled. The approximate date, class or type of submarine, the nature and location of the accident, the casualties and damage and the source of information are tabulated. (U.K.).

The details of how to build a cheap, practical radiation monitor are given. It consists of two units, a self-contained Geiger ratemeter and a separate pulse counter which plugs into the ratemeter and uses the same detection circuitry. This article gives full instructions for building the pulse counter. The Geiger ratemeter is described in a separate issue. A circuit diagram is given as well as a parts list and construction advice. The nature of the radiation monitored is described and the units used explained. Background radiation is explained and radiation levels recorded for various sources using the Geiger counter are listed. The use of the monitor and the error levels that can be expected are discussed.

A cheap, practical radiation monitor is presented. It can be used both for instant dose-rate checks and for long-term accurate counting. It consists of two units, a self-contained Geiger ratemeter and a separate pulse counter which plugs into the ratemeter and uses the same detection circuitry. This article is concerned with the ratemeter. The main components and circuit are described. A circuit diagram and an explanation of how the ratemeter works are given. A parts list and hints on construction and calibration are also given. The counter is described in a separate article.

Some of the ways that radiation can be detected and measured are discussed. The radiation types, levels and effects of acute radiation exposure over the whole body are mentioned briefly. Radiation dosage over a period of time can be measured by a dosimeter. A small, low cost quartz fibre dosimeter available commercially is recommended for measuring radioactivity levels in milk, water and food, preferably in conjunction with a Geiger-Mueller tube. A description is given of a simple general purpose Geiger-Mueller tube. A circuit diagram is given for a simple ratemeter which includes a GM tube.

The author reviews three books about energy policy, particularly in relation to nuclear energy. From these, which were all published before the Chernobyl disaster, the reviewer identifies two main problems relating to nuclear energy - immediate safety and disposal of nuclear waste. Risk analysis is seen as unhelpful in allaying public fears as it is the nature of the risk of nuclear accidents, rather than its numerical probability, that is frightening. A paper on the assessment of Best Practical Environmental Options (BPEO) for management of low and intermediate-level solid radioactive waste, is referred to when commenting on nuclear waste disposal. Ordinary people have two political obligations with respect to nuclear energy - first to demand knowledge and examine further reassuring information. Risks taken will then be taken with proper information obtained first. Secondly, to look beyond the short-term consequences of a nuclear programme. To fulfill these obligations policy-makers have to be educated to be open and honest about the nuclear future and to be seen to be looking further ahead than the immediate future. (U.K.).

This is the biography of a man obviously much liked and respected. It gives some personal details but is mainly concerned with his scientific work and achievements on major projects. Thus, some background information on those projects is also given as a context to the work of John Adams. The biography is written in sections; early years, the creation of CERN, Adams at CERN 1953-1961, Adams and thermonuclear research 1958-1969, (which includes his Directorship of the Culham Laboratory), Adams and the Ministry of Technology 1965-1966, member for research of the UK Atomic Energy Authority 1966-1969, Adams at CERN 1969-1984 (as Director General of the SPS, as Executive Director-General of CERN 1979-1981 and work at CERN up to 1984).

Oil production in USSR has decreased continuously 2 years of 1984 and '85. The reason for depressed oil production in USSR, No. 1 production volume and No. 3 confirmed reserve quantity at present in the world, is the delay of development technology. USSR is importing most of industrial materials and technologies from the Western countries, the cost of which is compensated by 60% by oil export. However, the quantity of Russian crude oil export was decreased greatly by 17% from the previous year, because of high prices. In addition, the price of crude oil suddenly dropped, resulting in an estimated oil export income reduction of 40% or more in 1987. The production quantity in 1987 has been slightly increased to 610 million tons because of increasing equipment investment. However, the quantity might become again lower than 600 million tons in 1990. These are caused by recession in equipment investment due to shortage of foreign currency. (2 tabs)

This system provides high comprehensive energy efficiency by combining shaft power with waste heat recovery with driving power of gas turbine, etc. The system is classified into power generation, heat pump and moving power. The power generation system is a cogeneration type on-site system bringing about ahigh efficiency of 70 - 80 % compared with 35% of energy efficiency for conventional power generation. In addition, waste heat from gas engine can be used. The heat pump system brings about 1.5 or 2 times as high as the motor heat pump or the boiler, against primary energy. The moving power system can be operated exactly according to demand by means of revolution frequency control in a high efficiency using waste heat.(11 figs)

Agency of Natural Resources and Energy published Report of Cogeneration Operation Standard Study Committee in May, 1986. The contents include (1) technical requirements for incorporation to ordinary utility power system, (2)

specification of utility reserve power, (3) safety measures for gas turbine, gas engine, etc. Technical Guideline for System Connection is issued for (1). The reserve power contract agreement, applicable to nonutility power generation system, is launched (issued Aug. 15, 1986). Regarding incorporation into ordinary utility power system, no technical matters will occur in principle provided that supply reliability and safety are satisfied. (2 tabs)

Mechanical properties of cellulose acetate were studied by carrying out a uniaxial tensile test and a short-time creep test at five different atmospheric temperature. (1) Static tensile test shows a behavior of complete viscoelastic body. (2) Young's modulus and yield stress can be expressed by a primary function of an atmospheric temperature. Poisson's ratio is 0.41 irrespective of temperature. (3) Stress-strain relation is independent with the atmospheric temperature when a yield point is defined as a point where the plastic strain is 0.2 %. (4) A short-time creep experiment shows that a transfer coefficient in a conversion curve of creep compliance is expressed in a primary function of the atmospheric temperature. (5) An equation was obtained for creep compliance with functions of atmospheric temperature and time. (12 figs, 7 refs)

Cobalt-based amorphous alloy with low magnetstriction was examined for its practical usability for a high frequency core. Especially Sm was added to enhance its heat stability. The result of examination was as follows: 1) Heat treatment in the magnetic field was effective for Co-based amorphous alloys. 2) Addition of Sm increased the electric resistance. The presence of Ni increased the temperature of crystallization. 3) Addition of Ni reduced both the Curie temperature and the saturation magnetization; it increased the electric resistance and reduced the coersive force. 4)Value of Hc = 115 Oe at 100 KHz indicated that Co-based amorphous alloy was superior to Fe-Nialloys for a high frequency core.

Structure of soot particulates exhausted from a diesel engine has never been considered in the past proposals for their formation or oxidation processes. This study was made to clarify the fine structure of the soot particulates by means of an electron microscope. (1) Microscopic sample should be collected on the microgrid with 1 micron level of pore size, as the magnification is high as 300 -400,000 times. (2) Although the typical layer plane structure which characterizes the graphite carbon crystal is not observed inside of soot particulates, it is observed in the peripheral portion with 0.35 nm of average distance between the layer planes showing a little more layer structure. (3) Layer plane structure is not observed in the soot after the generation of heat although the soot particulates in the combustion stage show a certain degree of layer plane structure in the initial and middle stages of combustion. (11 figs, 7 refs)

Study on the thermal decomposition of fuel using a thermal decomposition equipment clearly indicated the difference in the process of decomposition between the light oil and the liquefied coal oil which contained high amount of aromatic hydrocarbons. The differences are summarized as follows: (1) There is a definite correlation among setane index, delay in ignition, and miscellaneous engine characteristics, in a fuel mixture of coal liquefied oil and light oil. Qualitative prediction of the combustion characteristics of the engine can be made by measuring API specific gravity and 50 % distillation temperature. (2) Under the same combusting condition, a fuel with higher content of the aromatic hydrocarbons gives higher smoke-evolving temperature. (3) Aliphatic hydrocarbons in the light oil are decomposed into hydrocarbons with lower boiling point by the break of the C - C bond at 400 - 500 {sup 0}C. At around 600 {sup 0}C and higher, they are converted by polycondensation into cycloaromatic hydrocarbons. Liquefied coal oil which contains more aromatic compounds does not decompose so much, but turns into benzene and naphthalene, etc.. (9 figs, 1 tab)

This analysis is related with individual room radiator when a collective home or a hotel is centrally heated by means of a direct heating system. Since the rate of convective heat transfer from the heated flat plates is affected by the surface temperature of the flat plate itself, temperature difference between the

flat plate and the ambient air, and by the size of a cavity, the heat transfer is evaluated by the calorimetry for various conditions. The aspect ratio of the flat plates used in the present observation are 1.0 and 1.5 respectively, and the gap between the vertical wall of the cavity and the flat plate in which the surrounding air is drawn is changed from 0 mm to the infinity. In addition, air movement around the flat plates and the cavity wall is visualized by using cigarette smoke, and is applied for the analysis of the heat transfer characteristics of a heater which is simulated by the vertical flat plate. (10 figs, 6 refs)

A grab with an expandable ring can be fixed in an opening of the tube plate of a steam generator of a PWR allowing a reliable fastening of a remote manipulator for maintenance or verification.

/sup 170/Yb Mossbauer measurements show that magnetic ordering occurs within the Yb sublattices of YbCo/sub 2/Si/sub 2/ and YbFe/sub 2/Si/sub 2/ at 1.7 and 0.75K, respectively. The saturated magnetic moments are 1.4 and 2.0{mu}/sub B/ and are directed near directions perpendicular to the local tetragonal symmetry axis. These moments and the observed 4f-shell electric-field gradients can be accounted for in terms of Yb/sup 3+/ charge states experiencing crystalline electric fields.

We performed electron tunnelling experiments into superconducting YB/sub 6/ (T/sub c/=7.1K), using natural oxide as a barrier. In the second derivative of the current-voltage characteristic, we found two peaks corresponding to a shoulder around 5 meV and a peak around 8 meV, respectively, in the Eliashberg function. Our data allowed for inversion of the Eliashberg equations without consideration of proximity effects. The results indicate substantial electron-phonon coupling for the translational modes of the Y and B/sub 6/ sublattices, while the coupling to the torsional and deformational modes of the B/sub 6/ sublattice appeared to be weak.

EXAFS and XANES spectra at the edges of Cu and Y have been measured in the YBa/sub 2/Cu/sub 3/0/sub 9-{delta}({delta}4A2) superconductor. The oxygen coordination around the two metals is found to generally agree with the model suggested by diffraction experiments, especially as the occurrence of two distinct distances between Cu and O along the perovskite structure c-axis is concerned. Conversely, some evidence is found for a partial occupation of the oxygen sites in the yttrium plane, a result excluded by diffraction experiments. This is better supported by EXAFS spectra at the Y-edge. The XANES spectra of the superconductor are remarkably different from those of Cu oxides suggesting the presence of both divalent and trivalent Cu, in agreement with EXAFS and diffraction results.

The YBa/sub 2/Cu/sub 3/O/sub 7/ compound has been prepared as a single-phase material. It exhibits a sharp superconducting transition around 93 K which is observed consistently by resistance and magnetic-susceptibility experiments. Upper critical fields H/sub c2/ have been measured just below T/sub c/ up to 42T, using a high pulsed magnetic field. We conclude that the H/sub c2/ value at 77K is about 80T and that the extrapolated value at O.OK could exceed 250T.

We have measured X-ray diffraction (XRD), high-resolution electron microscopy (HREM), resistivity and susceptibility for a series of differently prepared YBa/sub 2/Cu/sub 3/O/sub 7-{sigma} samples. The high-temperature superconductivity was studied as a function of variable quench temperature. Quenching above 820/sup O/C leaves the sample in the tetragonal phase and destroys the superconductivity. We suggest that the superconductivity is located in the CuO chains which are extremely sensitive to oxygen loss.

We show that a bidimensional electronic model can explain both the large values of T/sub c/ and the low values of {gamma}=Cv/T observed in the superconducting copper oxides of mixed valency. It is well known that two dimensional crystals exhibit logarithmic singularities in the electronic density of states. If we assume that the Fermi level lies in one of these singularities, we give an

expression for {gamma} and the Pauli susceptibility chi/sub p/. The calculated values are in good agreement with recent experiments. For a weak coupling superconductor, using B.C.S. theory, we found that T/sub c/ is proportional to exp(-1/{radical}{lambda}, in 2 dimensions, where {lambda}is the coupling constant. For a low value of {gamma}, {lambda}is small and exp (-1/{radical}{lambda} is much greater than exp (-1/{lambda}, expression valid in 3 dimensions.

Two phenomena are pointed out which, if observed, would testify that the superconductivity in the Bechgaard salts belongs to the triplet pairing: excitation of the spin waves in the radio-frequency fields and the superconductivity restoration in high enough magnetic fields.

Magnets for Magnetic Resonance Imaging (MRI) are the first and the most important industrial application of Superconductivity. The design of MRI superconducting magnets and their performances are presented in this paper as well as electrical and cryogenic problems induced by the particular operating conditions of MRI systems. The reliability of MRI superconducting magnets has been etablished and work now in progess which is expected to improve the performances and to reduce the cost and the complexity of the magnet design.

Safety and reliability are increased in a glovebox with a pneumatic control circuit for maintaining depression inside and connecting alarms. The system is independant of an electric power supply.

A box for sample transfer, in controlled atmosphere, from for instance a glove box to another leakproof cell is described.

A ring for fastening tubes with conical ends with only one manipulator is described. It is opened by compression of a spring with the manipulator grip, placed on the tubes to fasten, closed by releasing the pressure and locked.

A device for joining two containment enclosures during transfer of materials or products is claimed avoiding seal wear during the rotation of the double closure.

A mechanical device is claimed for transfer or storage of materials from a container to a containment enclosure avoiding contamination.

The container is designed for closing it by a simple pressure on the lid comprising a part that can be deformed by elasticity. Moreover the lid comprises an injection hole for encapsulation. The design allows automation of radioactive waste conditioning.

The deformation of a mechanical structure: manipulator, robot with several rigid elements can be monitored by an optical system comprising light beams and photodetectors.

A case report of falsely elevated serum hormone values measured by radio-immunoassay (RIA) is described. The radio-immunoassays concerned have a first antibody raised in rabbits and mostly a separation technique based on a second antibody-solid phase system. The presence of heterophyle (anti-rabbit) antibodies in patients' serum is proved.

Fifty-two women, aged from 25 to 41 years, with infertility due to chronic anovulation were admitted to the study together with 36 age-matched controls with proven ovulatory cycles. Paired plasma (3 ml) and whole unstimulated saliva (10 ml) samples were collected over a 30 day period, starting from the first day of a menstrual bleeding, in patients, and throughout the menstrual cycle, in controls. Salivary progesterone levels, measured in women with infertility, ranged from undetectable values to 16 pmol/l during the first, and from 36 to 98 pmol/l during the second half of the monitoring period. In eugonadal women the steroid levels ranged from 34 to 46 pmol/I and from 96 to 780 pmol/l during the follicular and luteal phases, respectively. The saliva/plasma progesterone ratio ranged from 0.58 to 2.71 p. cent and a good correlation between salivary and plasma levels was found at each time of monitoring. Many (86 p. cent) of

patients, which were randomly allocated to a low-or high-dose epimestrol administration schedule, appeared to be sensitive to the drug, achieving, after therapy, salivary progesterone levels which were within the range of controls. Since correct assessment of luteal function in basal conditions and during therapy requires multiple steroid measurements, and since saliva can be obtained by non-invasive techniques, salivary assays represent an attractive alternative to plasma ones for monitoring ovarian activity, also during specific treatment.

Five direct radio-immunoassay kits for the dosage of 17 {beta}estradiol were assessed for their usefulness to monitor the serum values of 17 {beta}estradiol in stimulated and natural ovarian cycles. Prerequisites included a turn-around time of 4 hours for an assay of 100 tubes and a range extended to at least 2000 ng/l. The following parameters were evaluated: characteristics of the standard curve, sensitivity, precision profile, within- and between-assay precision, analytical drift and linearity. We found that the five tested methods are technically suitable to monitor serum 17 {beta}estradiol in stimulated cycles but they all lack precision for low 17 {beta}estradiol levels as seen in the early follicular phase of natural cycles.

The purpose of this report is to provide radiological physicists with an accurate method for the determination of qualitative and quantitative characteristics of photon and electron beams with energies between 1 MeV and 50 MeV, used for radiation therapy, and for the calculation of dose to water.

Hundred forty-four correlations are reported between radiological simulation and CT-scan in cases of prostate adenocarcinoma without metastases treated from 1980 to 1986 exclusively by transcutaneous radiotherapy using the box technique with 25 MV photons. Forty-eight percent of the cases were intracapsular forms. On the basis of correlation criteria defined, the prostatic boost volume was shifted in the sagittal plan in 18 % of the cases. Suspect seminal vesicles were found in 60 % of the cases. Our treatment plans were considered correct in 65 % of the cases, acceptable in 26 % of the cases and unsatisfactory in 29 % of the cases. The corrections applied to the treatment plan do not vary according to grade but according to stage and concern mainly the posterior limit of the boost volume and to a lesser extent the superior and anterior limits. The boost volume should be determined specifically for each case. CT-scans thus seem indispensable in establishing treatment plans in prostate cancer.

Stage T3 and T4 oropharynx carcinomas are type of tumors with a very poor prognosis. Encouraging results claimed in 1979 brought us to initiate a new treatment modality of these tumors by radiotherapy with high fractional doses. 46 patients were treated with a combination of chemotherapy and transcutaneous irradiation from 1980 to 1984. Radiotherapy was the administration of a dose of 52 grays in 13 fractions and during 17 days. The loco-regional control rate after a 5 years period was 31% and the actuarial survival rate without any sign of disease was 14%. Tolerance to the treatment was poor: a grade IV radiation mucositis was observed in 80% of the cases. These results indicate that the use of high fractional doses does not lead to improvement in either the local control rate nor of the disease in the survival of the patients carrying advanced cancers of the oropharynx, but complications were more severe. These results do not incitate us to propose to set up a controlled study to evaluate the therapeutic value of this type of irradiation.

A survey conducted during 1986 evaluated medical and logistic aspects of total body irradiation for bone marrow graft, with particular analysis of type of protocol and functional consequences. Current tendencies were determined by comparison of findings with those of a survey conducted within the framework of the GEGMO in 1984.

A survey of dosimetric and technical aspects of total body irradiation was conducted among French radiotherapy departments at the end of the first trimester 1986. Findings were compared with those of the survey in 1984 conducted by the GEGMO (study group on bone marrow grafts).

The time and energy coordinates of the neutrino signals reported by the Mont Blanc, Baksan, IMB and Kamiokande-II detectors, respectively, are fitted to kinematics. Under the most conservative hypothesis the electron neutrino mass is found to be < 5.7 eV. If the first six Kamiokande events originate in one very short burst, the electron neutrino mass is (4.2 + 0.9/-0.6)*(48kpc/L)/sup 1/2/eV.

X-ray absorption of Ce obtained by partial secondary yield, is compared with previously obtained electron-energy loss measurements in reflection mode. The absence of a strong feature below 4p/sub 3/2/ threshold in photon absorption provides confirmation that the peak in EELS is nondipole in character. Theoretical analysis supports interpretation in terms of a p-f giant quadrupole resonance, a result which broadens the analogy between giant resonances in atomic and nuclear physics.

We have measured the kinetic energy of the ions H/sub 2//sup +/, D/sub 2//sup +/, H/sub 3//sup +/ and D/sub /3/sup +/ produced by the collision of helium on metastable neon, on molecular hydrogen or on deuterium: from measurements on H/sub 2//sup +/ and D/sub 2//sup +/ it has been possible to confirm the existence of a two-step Penning collision, the second step being a transfer from vibrational to kinetic energy. The measurement of the kinetic energy of H/sub 3//sup +/ and D/sub 3//sup +/ leads us to conjecture that a certain amount of (H/sub 2/)/sub 2/ and (D/sub 2/)/sub 2/ dimers is present in the target.

We construct the kink sector of the PHI/sup 4//sub 2/ quantum field theory, in the broken-symmetry phase, using Euclidean methods. The construction exhibits relations with differential geometry and statistical mechanics. In particular we prove that the Euclidean Green's functions of kinks are obtained by integration over section distributions of nontrivial bundles and are well defined as Jaffe ultradistributions.

A bosonic knotted string (BKS) should satisfy some conditions in order that the Nambu-Goto variational principle and the statistical sum could be correctly formulated; these conditions are given in terms of cobordism theory. Two spontaneous splitting mechanisms of the BKS are described. A possible interpretation of Montesinos ribbons as many-loop diagrams is examined.

An updated analysis of the structure of the neutral current in the neutrino-electron interaction is reported. Starting from the experimental results concerning all the four elastic channels muon neutrino-electron, muon antineutrino-electron, electron neutrino-electron and electron antineutrino-electron, the analysis includes radiative corrections and takes into account the correlation effects induced by the different measurements in the determination of the leptonic weak-coupling constants. The values epsilon L = -0.273+-0.018, epsilon R = 0.228+-0.022 are obtained for the chiral couplings in a model-independent analysis or, equivalently, g/sub V/=-0.046+-0.029, g/sub A/=-0.501+-0.028 in terms of the vector and axial couplings of the electron. This corresponds, within the minimal standard model scheme (rho=1), to squared sin theta sin/sup 2/ W = 0.227+-0.014, whereas the simultaneous estimate of both squared sin theta sin/sup 2/ W and rho leads to squared sin theta sin/sup 2/ W = 0.227+-0.015 and rho=1.001+-0.056.

The missing-mass spectra for the /sup 3/He(p,d)X reaction (B/sub x/ = 2, T/sub x/ = 1) have been measured at T/sub p/ = 1.2 GeV for {theta}sub d/ = 33/sup 0/. Narrow structures have been observed at M/sub x/ = 2.122, 2.198 and possibly 2.233 GeV with FWHM, respectively, equal to 5.2, 8.1 and 13 MeV. These results, obtained under new kinematical conditions, confirm previous data.

The unknown isotopes /sup 70-74/Ni and /sup 74-77/Cu were identified in thermal neutron fission of /sup 235/U, using the recoil separator LOHENGRIN and {Delta}-E detection techniques. Isotopic yields, for preselected values of ionic charge and kinetic energy of the fission fragments in the mass range A=70 to 80, were measured down to 10/sup -9/ fragments/fission (f/f). Mass yields for the masses 70 and 71 and elemental yields for nickel and copper are estimated.

The relevance to the damping of the giant resonances, of the anharmonic coupling between the normal modes, is investigated in a fluid-dynamical model. It is found that this mechanism leads to a weak damping which, however, increases very drastically with the wave vector, implying a very short lifetime for high multipolarity or very energetic modes.

On n/sup +/ -GaAS substrates, gold-germanium eutectic films with a nickel overlayer, silver-germanium eutectic films with a nickel overlayer and aluminum-germanium films were evaporated. Samples from each of these three types of contacts were furnace and laser annealed with a pulsed excimer laser for optimum results. Gold-germanium and silver-germanium films gave ohmic contacts under both types of annealing. The laser annealed gold based contacts had a better surface morphology and somewhat smaller resistance than its furnace annealed counterpart. In case of silver based contacts, it was the furnace annealed contacts that had a lower resistance and better morphology. In case of aluminum based contacts, furnace annealing did not give an ohmic contact; with an anti-reflection coating, laser annealing gave ohmic contacts, which, however, were much more resistant and rough, compared to the gold and silver contacts.

The Kondo lattice model is studied in the limit of an exchange interaction large compared to the hopping of conduction electrons: it is shown that in this limit an effective attractive interaction between nearest-neighbour electrons with antiparallel spins arises in second-order perturbation expansion, and this effective interaction leads to d-like superconductivity in the simple cubic lattice. Moreover, an enhancement of the effective mass at the Fermi level can be obtained when the number of conduction electrons per site is close to one.

The decisive factor of geothermal energy development is to improve the exploration techniques. By effectively carrying out the selection of promising development spots and the decision of well drilling positions, the geotherm development exceeding existing energy sources becomes feasible. There have been many problems in conventional geotherm exploration such as the high cost and long work period, therefore, it was decided to advance the research on geochemical exploration techniques which are relatively simple and can be carried out with low cost. When the techniques of geochemistry are used, for example, in the case that there are hot springs or fumaroles, the temperature, origin, properties and so on of underground hot water reservoirs can be estimated from their chemical composition. The method of examining the mercury concentration in soil and soil air has been in practical use in the geothermal districts where the ground surface symptom lacks. This time, the method of investigation using radon, thoron and gamma ray as the exploration indices was newly studied. The index compositions for geochemical exploration, new exploration index compositions, the method of measurement, the basic investigation and on-the-spot investigation are reported. (Kako, I.).

As a part of hot-dry rock fracturing and development of thermal extraction technique, change of elastic longitudinal wave velocity (Vp) caused by hydraulic fracturing in rock specimrns were studied. Granite specimens were stressed from two horizontal directions and fractured by hydraulic pressurizing from vertical bored direction and Vp change was measured before, during and after fracturing. Vp was accelarated with increase of intermediate principle stress and in the area where high pressurized water penetrated and the latter factor had larger influence. Vp change depended on the direction to which penetrated water spreaded and on the direction of fractured plane, and when the width of fractured plane was very narrow like these experiments, Vp was large influenced by spreading of penetrated water rather than fracturing. (11 refs, 12 figs, 1 tabs)

Equations describing unsteady distribution of temperature, pressure,and saturation in the two-phase flow system in porous medium were derived, and some hydraulic characteristics of the two-phase flow system were investigated. Effects of change in external loads on geothermal state could be neglected. Perturbing a quiscent horizontal reservoir by small perturbation, a diffusion equation concerning propagation of pressure change was deduced. Checking up its

coefficients, followings were clarified: The most significant hydraulic storativity (compressibility) of the system was originated from the phase change Its value depended mainly on temperature. Therefore it is very important from the hydraulic viewpoint to elucidate the distribution of underground temperature Heat conductivity may affect the propagation of pressure change in the two phase reservoir of which permeability is 10{sup -3} darcy in the magnitude and temperature is below 200-250. (11 refs, 6 figs, 4 tabs)

Radioactive mineral ages in some granite bodies obtained by K-Ar, Rb-Sr and fission track methods had specific closure temperature estimates respectively and their thermal histories could be clarified by these methods. Rokko Nunobiki and Mikumo plutons, and Tanakami stock were found to be cooled slowly compared with Kumano acidic body from their radiometric ages. More shallow the intrusion and smaller the body, more rapidly the cooling rates of the formers. The latter began to cool slowly at first as uplift and then progressively quicker as the surface was approached. K-Ar ages for Kurobe granite pluton intruded 50Ma ago were in proportion to square root of the altitude and could be explained by cooling from the upper surface. High temperatures in the tunnel near Sennin Dam along Kurobe River were caused by residual heat of the granite body. (25 refs, 6 figs, 4 tabs)

Majour items of this lecture covered the assessment on the quantity of U.S. geothermal resources. The geothermal resources are classified into 3 categories; high temperature (150{sup 0}C or above) at which power can be generated by the hot water convection system, medium temperature (90{sup 0}C - 150{sup 0}C) for direct use (multiple purposes) with the hot water convection system and low temperature (90{sup 0}C or less) in which the geothermal system includes the hot water convection system and heat conduction dominant zone. For assessing energy stored in the reservoir, the volumetric method is used, in which multiplication calculation is used with the 3 parameters of the volumetric specific heat of a mix of water and rock in ratio 15:85, volume of reservoir and difference between reservoir and annual mean atmospheric temperatures. Other explanations include terrestrial temperature gradient map in the U.S.A., quantity of energy in the hot water convection system, etc. (3 figs, 2 tables, 1 photo)

The latest information of the geothermal development in U.S.A. was gathered by visiting to Geysers Geothermal Power Plant in the world largest geothermal field, the steam and binary cycle power plants in Imperial Valley, and Lawrence Berkeley Laboratory of University of California. Concerning Imperial Valley zone, the single flash generating system in Salton Sea area, and the 2-stage binary cycle generating project in Heber area were reported. Concerning the Geysers Power Plant, desulfurization technique of hydrogen sulfide against envionmental regulation was reported in details. Many information about the MT method for geothermal exploration are obtained, and it was impressed that the revolutional progress for MT method would occure in near future. (6 figs, 5 photos)

Hydrothermal alteration minerals, which are formed when hot water reacts on rocks in a geothermal zone, contain a great deal of information concerning the hydrothermal activities important for the geothermal exploration. Wairakite is an index of the high temperature hydrothermal activities in a geothermal zone since it is formed at 200{sup 0}C or more. The kind of alteration mineral is greatly affected by the chemical character of the hot water. Therefore the chemical character of the hot water which formed an alteration zone may be deduced by surveying the kinds of alteration mineral in the zone concerned. Since in many cases, hydrothermal activities are governed by fissures of rocks which were caused by a fault or fold of strata, the information about the change etc. of the passage or chemical character of the geothermal fluid is obtained from the distribution and outline of the alteration zone and the kinds of alteration mineral. In order to elucidate whether or not the hydrothermal activities which formed the alteration zone concerned still continue now and whether or not the information about the zone concerned reflects the current geothermal activities, it is important to determine the time when the alteration

action occurred. Furthermore, from the alteration minerals collected during the drilling of a production well, the prospect and other points of the well can be assessed. (5 figs, 1 tab, 9 refs)

There exists no MT technology yet in Japan which is usable at a practical level. Therefore, the conditions of development are: (1) A device should be able to be manually transported in order to make a measurement at a point where a car traffic is possible. (2) Quality control of the data obtained should be fully possible. (3) Highly dense measurement should be possible to match the complicated geological structure. More concretely saying; (a) Measuring device: Weight of the measuring part must be less than 25 kgs per unit. Data transmission distance should be above 5 km. An optical fiber is ideal for a transmission path. (b) Data processing technique: It is necessary to develop a device which enables to judge the correctness while obtaining the data to check the accuracy of the data. (c) Analytical technique: To develop a quasi-3-dimensional model analytical technique which involves a two-dimensional forward analysis, and a two-dimensional inverse analysis. (d) Economy: Cost of survey per one measuring-point is to be reduced less than half of the current cost. (3 figs, 3 tabs)

This is the report of the result of the Curie points analysis of the existing data owned by the Geological Survey of Japan together with the result of the survey of the nation-wide distribution of the magnetic fields of the earth in Japan which NEDO contracted with Geotricks Co., USA during the period from 1980 through 1983. The data were obtained in the measuring line interval of 3 to 4km. The results of the analysis were arranged in the whole Japan contour map of the Curie points which indicates in the constant depth the Curie constant temperature level representing 580{sup 0}C under the ground. The depth of the Curie points is 7km or less under the sea level in the shallowest area and 20km under the sea level in the deepest area. (1 fig, 2 photos)

The survey has been launched in 1980 to study nation-wide distribution of geothermal resources. Major survey methods in use include the remote sensing technology for geological survey, Curie point method for heat sources and the gravity prospecting method for base structure, etc. Thus, districts having high probabilities of resource preservation are extracted and selected while compiling prospective geothermal energy resource map and section model chart, etc. in 1/200,000 scale covering overall Japan in 1983. These surveys provide the primary assessment. Typical 4 areas will be selected for each type of geothermal energy among these districts and surveyed additionally, thereby subjected to comprehensive analyses concerning the scale of heat source, reserve structure and geothermal fluidic behavior. (5 figs, 1 photo)

A underground thermal structure become able to estimate with mathematical models. A new boundary condition was proposed concerning heat discharge from a permeable surface and this condition was applied to Takenoyu in Kumamoto Prefecture to analyze the geothermal structure and the results were compared with field data. When surface permeability is incorporated in boundary condition , it becomes necessary to consider heat discharges due to heat transfer and springs. When both heat discharges are considered, surface temperature becomes discontinuos and numerical solution becomes more difficult to obtain. But it became possible to get numerical solution of heat discharges due to heat transfer and mass discharge by applying this proposed boundary condition. The optimal model was applied to Takenoyu geothermal area and calculated results of heat and mass discharge and underground temperature distribution agreed well with observed ones. (15 refs, 9 figs, 1 tabs)

An outline of the geothermal energy development survey, carried out by NEDO, are described for the 11 zones where the entire surveys are completed. The 11 zones are the east part of Hachimantai, downstream of Dosan River, Kurino, Tearai, Kimofuri, Okiura, west part of Deshiku, Uzawa, Okachi, Okuaizu, Shimokita, vicinity of Lake Ikeda and north part of Azuma. Survey item include the surveys of geography, geochemistry, electricity, electromagnetism, geothermal flow and test boring. As a result of the survey, it is revealed that there are high-

temperature zones of 200{sup 0}C or above except for Okiura, Deshiku and vicinity of Lake Ikeda.(2 figs, 2 tabs)

Cetyl-trimethyl-ammonium bromide (CTAB) was added to sodium silicate solution and geothermal hot water (Ohtake Geothermal Power Plant and Hatchobaru Geo-thermal Power Plant) to precipitate silica. 1) CTA ions do not react with monosilicic acid, but only the polymerization among the polysilicic acids proceeds and causes silica to precipitate. Optimum pH for the silica precipitation is 6 - 7 and the higher concentration of polysilicic acid will cause more precipitation. 2) When added to geothermal hot water, the silica precipita-tion increases with the increase of CTAB concentration within the range of 10{sup -7} - 10{sup -4} mol dm{sup 3} concentration. Almost all poly-silicic acid precipitated at 10{sup -4} mol dm{sup 3} when measured for silica precipitation after 5 minutes. Total concentration of silicic acid was higher in the Hatchobaru geothermal water than that of the Ohtake geothermal water. (10 figs, 14 refs)

Geothermal reservoir evaluation is to create a geothermal reservoir model by collecting data to get information about the structure and condition of the geothermal reservoir under consideration and analyzing the collected data using computer simulation and, using the created model, to predict the behavior of the geothermal reservoir after steam production. NEDO has been developing techniques for this evaluation by implementing a four-year plan which started in 1984. There are four points on this development: (1) A conceptual model on which to base analysis of the entire geothermal system should be created; (2) Actually measured values should be compared with the results of simulation based on a tentative model to modify the model so that the temperature, pressure, flow distribution, and other gethermal parameter can be determined quantitatively; (3) The permeability, which is one of geothermal reservoir parameters, can be evaluated with a high accuracy by conducting well testing; (4) A power generation plan should be worked out according to the quantitatively established model. The model field is the Kirishima area in Kyushu. (6 figs)

This project has been executed as a 5-years plan since Oct, 1983, and is in progress as summarized below. 1) In the study of the rock body deformation and destruction behavior in the underground environment, experimental data are now arranged, e.g., concerning the stress-corrosion-cracking; numerous branched cracks are observed in the high temperature/ pressure water. 2) According to the monitoring of destruction stage of the underground rock body and measurement of the underground crack shapes by the AE (Accoustic Emission) method, a case study of assessment of the underground cracks was carried out. 3) New plan and evaluation methods in progress are a new rock pressure measuring method, a new interpretation of pressureflow curve of the hydraulic cracking, an ISRM boring core sample destruction resilience test, etc. (11 figs, 2 tabs, 17 refs)

This report describes the outline of the measures for the lost circulation and the manner of proceeding R/D in the study group which started in 1984. Detection of the location, scale, shape of the lost circulation layer is presently made manually; preventing agent for lost circulation is made by the repeated trial and error method until it reaches the layer and starts crosslinking; cement slurry involves such problems as coagulating time at high temperature, contamination by mud slurry, impermeability into the fine local structures, etc.. For the future it is required to develop a triple component radiosonde for the flow rate, temperature, and pressure, an additive for the cement slurry, and chemicals with proper heat stability, curing speed, and permeability. Report on the R and D at Sandia National Laboratories is added as an appendix. (9 figs, 3 tabs, 3 refs)

This is an outline report on a geothermal layer detecting system and its field test during the 8 years since 1976. Common systems for the layer detection are layer detecting cable, layer detecting vehicle, cable head, water-stopping mechanism, insulation mechanism for protection of in-well electronics, arm drive mechanism, and on-the-ground instrument system. Based on the above, 11 items of layer detecting machines were developed, and its field test extended over 200 km

through the 3 stages of the initial, middle, and final stages. As a part of the above tests, such examples introduced are temperature recovery test, evaluation of injection and production layers by a flow-meter, evaluation of fracture, and distinguishing the rock phases, etc.. (14 figs, 5 tabs)

This is an outline report on the development after 1981 which had been carried out since 1974 by Japan Industrial Machiney Association. A roller cutter bit was trially made aiming at improving the heat resistance and tested with a bit tester and in the field, obtaining a result of practical applicability. Concerning the air friction bit, the target is a bit which requires no lubricant. Although the ultra-hard liner of the bit axis was treated with titanium nitride for this purpose, the result indicates the need of further study. R/D are in progress for a seal for a bit, protector of rotating head, and a percussion drill; a certain level of protection has been obtained. (5 figs, 1 tab)

This is a report of the 5-year research started in 1980 with an experimental plant in Akita Prefecture. Number of the test wells (1400 m depth) was four and various tests were made respectively for the wells to collect the evaluation data. Verification test on the collection/reinjection was carried out with NO.1-NO.2 wells (each roughly 100 m apart) at 20 t/h flow rate and No. 4 reinjection well, 1200 m apart, at 60 t/h flow rate. In this test, such phenomena as reduction of the reinjected amount in the initial period, reduction of reinjection temperature, and the increase of the reinjected amount due to the operation stoppage were observed. On the basis of above data and the basic test, a hydraulic crushing test for the geothermal reservoir was carried out at 60 t/h test. In the test, geothermal water with 68{sup 0}C temperature was used to heat the river water (2{sup 0}C) 40 t/h up to 55{sup 0}C. (6 figs, 4 tabs, 4 refs)

This study has been continued since 1980 on the development and proper selection per use of materials which excels in resistance to heat, corrosion, erosion, and abrasion. 1) Study on the corrosion damage mechanism: Damage by erosion is studied by a cavitation-erosion test, and erosion by an electrochemical method. 2) Evaluation study of geothermal materials: A simulation test and a local corrosion test are being carried out aiming to be completed by 1985. In an analysis by a regression method, correlation factors of each factor of 0.8 are targeted. 3) Study of new materials for the geothermal application: A complex tube is being developed wherein a ceramic material with high corrosion/erosion resistance is used in the inside, and a metal with excellent mechanical strength as an outer material. (9 figs, 7 refs)

Geothermal reservoir is evaluated in terms of correct assessment for the structure and state of the geothermal stratum and prediction of behavior of the reservoir layer during steam production. It is therefore required to urgently develop to precisely evaluate optimum power generation capacity, etc. for the reservoir layer before exploitation. The evaluation is carried out by creating qualitative and conceptual model for the entire thermal system and surveying quantitatively the natural conditions of the reservoir in that order. In detail, the process is carried out in the procedure of the measurement of permeability distribution - prediction of behavior after production - submission of proposed survey guideline - decision of optimum power generation capacity. The present project to be performed includes the development of software such as simulation codes, etc., establishment of method for collecting data of well drilling test, execution of drilling observation wells in 2 model field areas, analysis on each stage and modification and verification of the software in the process of assessment. (2 figs)

Ultimate target of the development is a portable nondelay 4 measurement 3 check MT method for surveying underground specific resistance in the geothermal area in Japan, in high accuracies. Nondelay 2 measurement double check MT method, developed so far, is reported. This instrument consists of magnetic and electric field sensors, DOP, DPU and a field optical link unit. Items of development, reported herein, include each elementary technologys, meter control program, data processing program, data quality check by real time processing and various

analysis technologies for the 1 and 2 dimension models (horizontal multi-layer structural underground models). A field test was performed in Hohi, Oita Prefecture in October, 1986 for measuring at 30 points. As a result, it is confirmed that series works from acquiring to analyzing data can be performed. (7 figs, 4 tabs, 1 photo)

Though many models have been proposed to give quantitative interpretation to self-potential observations, few theoretical studies have been made on the physical mechanism of its generation because of its complexity. In this study, observations of self-potential previously made at the Onikobe geothermal area are reanalyzed using the finite element method. The analysis employs a new model developed based on the fact that flows of heat existing in a geothermal area can act as a source for self-potential. Self-potential survey results are compared with calculations based on the model. It is shown that results of D{sub 3} survey line can be reasonably interpreted in terms of a thermal source model. For B survey line, on the other hand, observations cannot be explained by the thermal source model alone, but interpretation is possible by assuming that the generation source has relations with streaming potential. For analysis of self-potential anomalies, both the thermal model and the streaming potential model should be taken into account instead of considering one of them alone.(10 refs, 17 figs)

Observation of seismic noise was made at the Takenoyu area, where the ground-surface geothermal symptoms are evident and the noise-source is relatively less, in order to investigate the relation between the seismic noise and the geothermal phenomena. Results of the investigation are as follows: 1) Seismic noise at the Takenoyu area is originated from the geothermal activities and is stable. 2) Amplitude distribution of the seismic noise shows quite high correspondence with the distribution of ground temperature at 1 m depth. It generates from the point under a wide amplitude and propagates around in the form of a bodily wave. 3) Source of the seismic noise is not near to the ground surface, but is about 10 - 30 m deep. The noise is estimated to be caused by the boiling of hot water at the top of the geothermal reservoir from the viewpoint of relationship between the depth of the noise source and the temperature distribution of the well temperature. (23 figs, 25 refs)

A study was made on the relation between the geological structure and the geothermal symptoms in the Noya area, Central Oita prefecture by means of ELF - MT survey method. (1) In the vicinity of Noya village (zone A), geothermal symptoms were relatively significant and the apparent resistivity distribution was distinctively low. There was a good coincidence between the area of low apparent resistivity of 25 ohm - m and the area of high heat discharge. (2) Eastern zone of Noya village (zone B) showed less geothermal symptoms in comparison with the zone A, but is considered to have higher underground temperature. In the center of this site, a high resistivity zone was located, and was surrounded by a low sensitivity zone. A high resistivity zone was found extending over in the vicinities of Mt. Karutoyama in the north and Mt. Noinedaka in the south. (7 figs, 1 tab)

Observations were made on the seismic noise in Takinoue geothermal area, Iwate prefecture, giving the following informations. (1) Vibrations mainly of high frequency above 10 Hz are generated in connection with the flow of River Kakkonda. Its influence is extended over the area within 20 - 40 m from the river side. 2) The seismic waves generated by the activities of the steam supply system, mainly production well, reinjection well, and separator, have spectral characteristics of high frequency above 20 Hz. The radius of influence is about 150 m for the production wells. Around the steam pipelines, seismic noise of high frequency elements above 20 Hz is generated although limited in a narrow range. 3) Within the fumarole area, high frequency elememts above 20 Hz which seems to be due to a blow-out of steam and hot water from the fumaroles or by the flow in the shallow underground are observed. The seismic noise in the frequency band 5 - 15 Hz is dominant in the wide area around the fumaroles. (26 figs, 5 refs)

This analysis was carried out as a part of Analysis of the Reservoir Characteristics, a NEDO project entrusted by MITI. Discharge performance of Well DY-1 was analyzed by means of a simulator on the two-phase flow in the well. The analysis showed very good coincidence between the values calculated and actually measured. (1) Wellhead pressure of DY-1 well during the discharge was as low as 2.5 bar max., but a simulation on the well design in dicated that the wellhead pressure could be raised by enlarging a casing bore at above the flash-starting depth and by lowering the wellhead position. (2) Discharge of DY-1 well stopped by the depositing of calcium carbonate scale which seemed to have occurred ever since the start of the discharge. (3) This simulation analysis was quite effective for the under standing of the discharge performance and the scale deposition and for the design of the production wells. (18 figs, 3 refs)

Development of non-volcanic deep-seated geothermal hot water supply system, promoted by NEDO, is reviewed with a description on the results and future planning. In 1979, an experimental site was placed at Akita Pref. By 1982, 4 test wells of 1,300 m class were drilled for performing extraction and reinjection tests. The 20 ton/h rate test was performed continuously for 365 days up to May, 1983. The 60 ton/h rate test was carried out 45 days. Details of these tests are reported, indicating that the injection efficiency per unit power consumed for the latter test becomes about 2 times as high, available for mass supply by means of large-scale facilities. Based on the test data, a three dimension model of the deep-seated hot water reservoir is created for simulation. In addition, influence to ground subsidence is also surveyed. (6 figs, 2 tabs, 1 photo)

Basic study on the elementary technology for the total flow power generation is performed with particular emphasis on the inner seals (leakage characteristics of the labyrinth seal and the flat seal), uniform supply of steam and water (structure for supplying air by using inertia supercharging) and the expansion of 2-phase flow of steam and water. A test machine is designed and manufacturered (output 300 KW) and test operated at the works with a result of 54% engine efficiency and 290 KW shaft output. In addition, technical prospects are established through conceptual design of the 1,000 KW class practical machine. It is revealed that the total flow power generation can provide 14% higher output with 11% lower cost in the same inlet fluidic conditions, than the shaft gate power generation. Although manufacturing becomes prospective, there are various tasks remaining for fabricating large-scale system, such as reduction of unit weight per output, improvement of the structure and higher corrosion resistance to geothermal fluid. (4 figs, 3 tabs, 1 photo)

Development of the 10,000 KW class demonstration plant is required to prove comprehensive performance of a practical power plant with particular emphasis on economic merits and maintenability. For this purpose, research and development has been launched in 1974 while constructing a 1,000 KW class binary cycle power plant. Study on various elementary items (heat media, corrosion resistant materials, turbine shaft seal, heat exchanger) has begun in 1979. Four years later, the development of the down hole pump has been started to utilize weak-artesian well. Problems to be solved are summarized at economic performance of the plant, temperature drop in reservoir and scaling of injection well. Future tasks to be carried out include the development of cyclic power generation technology using the down hole pump, establishment of optimum thermal cycle system and construction of a plant conforming to the conditions of geothermal field. (2 figs, 1 photo)

Adjustable vane type vertical mixed flow pumps, which can change the setting angle of its vane during its operation, can be operated at higher efficiency than fixed vane type vertical mixed flow pumps in case when the operation is made in the wide range of flow. Because of this, the modification of vertical mixed flow pumps from the fixed vane type to the adjustable vane type has recently been promoted positively as an energy saving measure. In this view, this report describes about the conditions and structure, etc. concerning the modification from the fixed vanes to the adjustable vanes at the time of

inspection and repair of pumps used for many years. Although auxiliary equipment, panel and others are newly needed in connection with the modification to the adjustable vane type, the space for installation remains unchanged from the time of the installation of the fixed vane type pump. It is necessary to examine well the layout of the equipment beforehand. (7 figs, 1 tab)

Corrosion of cast iron in the sea water advances as the flow velocity becomes higher as a rule, however in case where a flow velocity distribution exists as the inside of a pump in operation, there is a phenomenon that a differential velocity cell is formed and the corrosion at the low flow velocity section is considerably accerelated contrary to the above. This article reports the results of the quantitative grasping of the differential velocity cell corrosion inside the pump through the experiment using actual pumps and of the examination of the ways to reduce it. As the countermeasures against the differential velocity cell corrosion, the following methods are effective: (1) In designing, consideration should be given so that the flow velocity gradient may become small and bearing in mind the area ratio between anode and cathode, the area of the cathode may relatively become small. (2) The material which is insensible of the differential velocity cell corrosion should be used. For instance, the adoption of the sea water resistant low chrome cast iron, etc. is also effective. (17 figs, 1 tab, 3 refs)

The downhole pump is developed aiming at pumping up hot water from geothermal well and using for binary power generation. The pump consists of a vertical multistage diagonal flow type, while the motor comprising a can structure oil-shield submersible motor. A practical machine will be developed after completion of manufacturing and testing 2 trial models in 2 phases, because technical difficulties are expected in the development plan. The target performance of test machine No. 1 includes a hot water flow rate of 50 ton/h, a hot water temperature of 170{sup 0}C and an installation depth of 400 m. Study on elementary components is carried out for thrust bearing and shaft seal, sealed oil, status coil, cable and motor tandem joint. Test machine No. 1 is completed in 1985 and tested satisfactorily in Kuju area, Oita prefecture at a hot water temperature of 170{sup 0}C for a period of 1,000 hours. The results will be completely transferred and referred to the development of test machine No. 2. (1 fig, 3 tabs, 3 photos)

Following results were obtained from the small scale hydraulic crushing experiment and the two-well connection and circulation test. 1) Ground pressure in the vicinity of the experimented site was maximum along the east-west direction in the horizontal plane; impedance of the fracture system decreased as the circulation time increased, and the flow rate of the pouring water out of the well I-2 decreased. This is because the fracture grew in the east-west direction from the well V-2 and crossed with the already existing fracture. 2) Temperature drop in the well I-2 at 17 m depth is quite significant in spite of the small flow-in quantity. Although water does not spring out at the mouth of the wells I-1 and V-1, fracture were suspected at several spots in view of the temperature measurement in the circulating test. It was also suspected that the increase of the fracture width and the expansion of the fracture due to the rock body cooling were in progress. (8 figs)

Development of a geothermal binary cycle power generation plant is, since 1979, in the stage of element research for the demonstration plant of 10,000 KW capacity. 1) Studies are made on both methods of single binary and double binary systems concerning the utilization of geothermal water. 2) From the viewpoint of NEDO's own survey on the overseas technology and petroleum-substitution energy, an independent system of a binary cycle power plant using downhde pumps for the purpose of handling the medium/high temperature geothermal water is being investigated. 3) Problems involved in the development are: a) R and D on the downhole pump. b) Improvement of economy (totalizing the surface and underground). c) Measures for the silica scale. d) Assessment of influence of the reservoir. (4 figs, 1 tab, 1 ref)

Fracture toughness of rocks at high temperatures is investigated to obtain information required for effective hydraulic fracturing of hot-dry-rock systems. In KIMACHI sandstone (Rock A), the maximum splitting load is comparable between room temperature and 100{sup 0}C, but increases as the temperature increases to 200{sup 0}C and then to 300{sup 0}C. On the other hand, it decreases in the case of ONADA granite (Rock B). The ceack generally propagates with increasing crack opening displacement accompanying the crack propagation increases with increasing temperature. The stress intensity factor becomes nearly constant at a crack length of about 85 mm in both rocks. Thus the value at this point is regarded as showing the fracture toughness. The fracture toughness of Rock A slightly decreases as temperature rises from room temperature to 100{sup 0}C, but increases above 100{sup 0}C. At 300{sup 0}C, it becomes about 1.4 times that at room temperature. In Rock B, fracture toughness decreases monotonously as temperature rises, reaching about 0.65 times that at room temperature at 300{sup 0}C.(16 refs, 11 figs)

In order to find an optimal design for the downhole coaxial heat exchanger, following results were obtained using a numerical simulator. Reverse circulation was more suitable than forward circulation to obtain more thermal output, because of shorter length of heat loss. Much higher outlet water temperature and net thermal output could be obtained with an insulated inner piping. Due to difference in water density, circulation pressure arose in the downhole coaxial heat exchanger, and no pumping work was required for circulation when temperature difference between inlet water and outlet water were sufficiently large and the design of heat exchanger was appropriate. Thermal output of this heat exchanger with an insulated inner piping and reverse circulation was much larger than that of a U-tube heat exchanger. Thermal output increased with increasing diameter of wellbore but the increase rate was smaller. The inner pipe diameter also related to thermal output and friction loss and well-head pressure difference were very sensitive to the inner pipe diameter. (17 refs, 10 figs, 7 tabs)

Some laboratory and field experiments of fluid circulation, and numerical approach were carried out concerning fractures created by a hydraulic fracturing technique to clarify the fracture aperture behaviors and flow behaviors when the geothermal energy from hot dry rocks were extracted by circulating fluid through fractures. The fracture under stress condition resulted 0.5 mm aperture distribution in Inada granite. Channels between wells comprised of multiple created fractures and joints. The fracture aperture distribution had influences on flow behavior and circulating flow rate and therefore coupled stress-flow analysis were required. In simulated four models, each model had different effects to applied items, that is, injection pressure, circulating flow rate, circulating area and flow rate distribution. (10 refs, 26 figs, 6 tabs)

NEDO is participating Phase 2 of U.S. Hot Dry Rock Project (since 1979) under the IEA implementing agreement. Major technical results, so far obtained, include deep parallel slope boring of hot hard rock (accumulation of boring technology for crystalline hard rock, development of abrasion resistant tools and devices for cutting hard rock at high temperature, such as rotary bit), practical use of various inspection layers in high-temperature and high-pressure well, development of direction and slope controlled tools and equipment, execution of hydraulic fracturing in deep hot well, study on optimum heat extraction based on injection water circulation (analysis of geopressure, execution of optimum hydraulic fracturing, improved accuracy of artificial reservoir selecting technology, establishment of optimum heat control for artificial reservoir), etc. Japan will participate in exploiting advanced HDR technology including expoitation, heat extraction and applications of geothermal resources. (2 figs, 2 photos)

In order to study the silica deposition mechanism in a reservoir in a geothermal power station in case of reinjecting geothermal water and the decrease of the permeability due to silica deposition, tests were conducted by supplying the Otake geothermal water of constant temperature and pH to a cylindrical cell

filled with alumina beads and rock particles. The flow rate decreased with time, and the decrease rate was larger with increase of silica concentration in the geothermal water. The initial decrease rate in rock particles was a little larger in alumina beads. Silica was mainly deposited at the column inlet and the silica scale amount decreased rapidly with distance. The relation between the permeability and the silica scale amount could be expressed by Kozeny-Stein formula. (6 refs, 13 figs, 1 tabs)

In pursuit of effective techniques for utilizing thermal energy of hot-dry-rock systems, high temperature uniaxial compression tests are carried out on AKIYOSHI marble, INADA granite, OGINO tuff and EMOCHI welded tuff to obtain information on the mechanical behaviors of heated rocks. The mechanical behaviours of heated rocks are very different among various rock types, with some rocks showing a tendency contrary to that of others. The values of compressive strength and secant Young's mudulus of OGINO tuff decrease as temperature increases up to 300{sup 0}C, and then they increase beyond that temperature. In EMOCHI welded tuff, these values increase with increasing temperature, whereas they decrease as temperature rises in AKIYOSHI marble and INADA granite. The value of strain at failure point becomes smaller in EMOCHI welded tuff with increasing temperature, whereas the contrary tendency is seen in other rocks. (15 refs, 5 figs)

Present status of coal deashing and desulfurizing technology ; Coal Cleaning, aiming at improving coal qualities, is introduced. Conventionally, established coal selecting technologies are used as coal cleaning process in broader sense. However, many disadvantages occur in coal applications if only coal processing step is used, in terms of lower ash and sulfur contents. In particular, various new methods, such as physical, chemical or bacteria technologies, have been positively studied to remove organic sulfur content directory bonded to the grain structure of hydrocarbon and ash content dispersed finely in the grain. Methods under development in Japan include oil addition granulation method (OA method) flotation, etc. There are many overseas reports for the OA process published and presented in international symposiums. (1 fig, 3 tabs)

The properties of hydrodenitrification product of coal tar pitch were examined and the denitrification mechanism of heavy distillate was investigated.The specific gravity, viscosity, softening point and carbon residue content of the product oil were remarkably increased as the denitrification reaction proceeds. Lowering of the boiling point by the nuclear hydrogenation of aromatic cycle in the product and the increase of affinity of the product to the non-aromatic extraction solvent make the product lighter. The contribution of hydrocracking is low. The light distillate seems to be denitrified in such a way that nitrogen compounds are selectively adsorbed on the surface of catalyst and the nitrogen atoms are eliminated from the saturated compounds after the nuclear hydrogenation. It is most probable that the C-N bond is dissociated from the product in which two to three aromatic cycles undergo the partial nuclear hydrogenation. (7 refs, 5 figs, 6 tabs)

Carbonization of 15 aromatics composed of 1 to 4 rings from benzene to pyrene, was made using tetrachloromethane as a promoter, and the reactivity and development of optical anisotropy were studied. Further kinds of carbon halides used as promoters were also investigated. The reactivity of aromatics in carbon tetrachloride increased as the number of polycyclic aromatic rings increased and the number of hydropolycyclic aromatic rings decreased. Lin-type molecules were more reactive than peri-type ones. Optical anisotropy tended to be better developed in those from lin-type molecules than from the ang-type and peri-type ones. Optical anisotropy tended to be developed with the increase of hydrocyclic rings and appeared more remarkably in lin-type molecules than in peri-type ones. The performance of carbon halides in carbonization was remarkable in halides which had higher chlorine contents and lower C-C1 bond dissociation energy. It was observed that in reactions with aromatics richer in aromaticity the growth of optical anisotropy was faciliated when a promoter of low chlorine content was used, whereas in reactions with aromatics richer in hydroaromaticity, it was

facilitated only when a promoter of high chlorine content was used. (8 refs, 16 figs, 6 tabs)

Two deasphalted oils produced by supercritical solvent extracion of heavy ends which were residues of CHERRY-P process were analyzed and the hydrotreatment with Ni-Mo-Al{sub 2}0{sub 3} catalyst was studied. The deasphalted oils were efficiently desulfurized and denitrificated, and polar compounds(P-2) and asphaltene were significantly reduced. The hydrotreated oils were suitable for FCC feedstocks. P-2 fractions were found to contain pyrrole- and amide-type compounds and the ratio of pyrroles/amides depended on extraction conditions but it was unchanged after hydrotreating. The amide-type compounds could be further classified into two groups which had different characteristics of hydrodenitrogenation. Polyaromatics in feedstocks were found to contain three ring aromatic compounds and dibenzothiophene derivatives as the major components but most of them were converted to mono-aromatics, di-aromatics and saturated hydrocarbons. The major components in the hydrotreated oils were three-ring aromatics which appeared to be less condensed than those before the reaction. (13 refs, 9 figs, 5 tabs)

Characteristics of Ni impregnated alumina catalysts were studied using two types of aluminas and methanol, ethanol and 1-propanol as solvents. The degree of Ni(2) ion absorption on alumina supports increased with carbon number of alcohol used. The degree of Ni reduction was expressed as the function of the total Ni content and the degree of reduction was independent of solvents and supports. The variance and average of Ni particle size increased with total Ni content. The rate of benzene hydrogenation was proportioned to the Ni surface area, and independent of solvents, supports and Ni particle size. (11 refs, 10 figs, 2tabs)

A 2-stage process, for separating and refining high-purity CO from the converter gas of high CO concentration (higher than 80%) for raw material of C{sub 1}, is tested by a 20-60 Nm{sup 3}/h pressure pulsation adsorption separation (PSA) pilot plant. High-purity (99%) CO can now be separated and refined at a recovery ratio of 60-70% simply at low cost by using the purging under vacuum with an adsorptive column and applying optimum pressure pulsation pattern for removing CO{sub 2} and N{sub 2} which could not be easily removed by conventional processes because of difficulty of separation and co-adsorptive property, respectively. Thus, the current separation technology can be modified to expand the scope of applications for the PSA method. In addition, other contributions of the system include the production of high-value added byproduct gas of steal making and diversification of raw materials for synthetic chemicals. (8 refs, 7 figs, 1 tab, 1 photo)

In order to separate and purify CO from the converter exhaust gas by means of a pressure swing adsorption method using zeolite, an experimental unit of a two-tower process was used to grasp the fundamental characteristics. After removing such strongly adsorbing components as CO{sub 2} and H{sub 2}O, an adsorption/separation coefficient was calculated for a CO-N{sub 2} system, CaA type zeolite was selected as an adsorbent, and the test on the influence of adsorbing pressure, concentration, and temperature on the adsorption characteristics, shows that the high pressure/low temperature is effective; concentration was an independent factor. Measurement of the cleaning characteristics, the relation between the washed CO gas quantity and the product purity, indicated the raise of the purity up to 99.9 % as the amount of the gas increased. The adsorption method adopted consists of four stages in a cycle, i.e., adsorption, washed gas. Recovery rate of CO was 75 - 80 %. (9 figs, 1 tab, 5 refs)

Catalysts useful for hydrodenitrogenation (HDN) of coal tar pitch were screened from 16 commercial Ni, Co/Mo, W bifunctional catalysts. The HDN activity decreased in the order Ni-Mo> Ni-Co-Mo=Co-Mo> Ni-W at test conditions in the activity measuerement apparatus. Catalysts containing Al{sub 2}O{sub 3} composite oxide promoted by P{sub 2}O{sub 5}, SiO{sub 2} or B{sub 2}O{sub 3} possess high HDN activities. Every catalyst had high hydrogenation activity but

at the same removal basis, Ni-Mo catalysts need relatively low hydrogen uptake in HDN and hydrodesulfurization (HDS) compared with Co-Mo catalysts. HDS rate was higher than HDN rate in all catalysts. Three Ni-Mo catalysts were selected as most suitable for HDN of coal tar pitch because they had higher HDN and HDS activities and lower increase of H/C(dH/C). (16 refs, 8 figs, 2 tabs)

Coal tar pitch was characterized for nitrogen type and average molecular structure to hydrodenitrogenate coal tar pitch. Coal tar pitch contained many molecules which had hardly naphthenic ring or alkyl group and were comprised of condensed aromatics. Number of naphthenic ring was one at the most and alkyl substituents were almost exclusively methyl. The average molecular parameters were 3 to 4 for n-hexane-soluble fraction, 6 for n-hexane-insoluble, toluene-soluble fraction and 18 for toluene-insoluble (TI) fraction. The nitrogen content was higher in the TI heavier fraction. Nitrogen was contained in basic components (BC) by 70%, in pyrrole type components (PC) by 20%, and in neutral type components (NC) by 10% and basisty was higher in the heavier fraction. Major nitrogen compounds were pyridine types in BC, PC in acidic components and hydroxypyridine types in NC. Basic nitrogen compounds had similar molecular structure with that of hydrocarbons, in which one or two carbon atoms were replaced by nitrogen. (12 refs, 2 figs, 11 tabs)

Since fuel oil meeting the requirements of current petroleum products can be produced by SASOL F-T synthetic process, the manufacturing process of hydrocarbon fuel oil from the coal-derived synthesis gas, downstream processes are being successively investigated. Mobile M-gasoline, MTG, process which produces gasoline from the natural gas-derived synthesis gas through methanol went into commercial operation in New Zealand in 1986. Although the gasoline suffices the quality of commercial gasoline by both fixed bed and fluidized bed systems, the price and service life of catalyst and control of by-product durene must be improved. Any STG processes have not been completed yet and the yield and quality of gasoline are inferior to those of gasoline produced by the MTG process. Applying two-stage process, the STG process will be more economically effective.(21 refs, 4 figs, 10 tabs)

The hydrogenative gasification of coal in the low-temperature region of 600{sup 0}C or under, especially the catalyst for in-situ hydrogenerative methanation of the volatile matters produced by the low-temperature dry distillation, was investigated using Shinyubari coal. Ni-montmorillonite intercalated compound has high catalytic activity, showing a conversion of 90% or more. The activity of Ni-supported catalyst largely varies according to the material of carrier in the order of montmorillonite > zeolite > titania > alpha-alumina > magnesia > silica {approx_equal}amma-alumina. Since montmorillonite releases intercalated water, most of the intercalated spaces are crushed in the working temperature range of 300{sup 0}C or higher of Ni-montmorillonite catalyst. Ni in the montmorillonite intercalated compound is dispersedly supported in form of metal on the surface and in the surface and in the intercalation of montmorillonite.(6 refs, 6 figs, 3 tabs)

Eighteen ranks of coal and twelve ranks of deashed coal were gasified with steam at 1185{sup 0}C by a high-heating rate thermobalance reactor to examine the gasification of coal in the high temperature of 1000{sup 0}C or higher. The minerals have catalytic action on the gasification of low grade coal even at the temperature as high as 1185{sup 0}C, while the minerals contained in high grade coal (C-content: higher than 75%) do not affect it. In the chemical reaction rate-determining gasification process of coal and deashed coal with negligible catalytic action, the gasification rate is lowered with decreasing of the pare surface area of char and with increasing of crystalline size of carbon. Even in the gasification at high temperature, the gasification rate is raised with increasing of the amount of oxygen trapped in the char (by flash desorption method).(25 refs, 10 figs, 1 tab)

As a part of gasification study on heavy fractions of coal, hydropyrolysis of five heavy oils having different characteristics was performed. The experiments were carried out, using a tublar flow reactor, at temperatures of 500 to

1,000{sup 0}C, pressures from 10 to 60 kg/cm{sup 2}G, residence times of 15 to 60 sec., and H{sub 2}/oil ratios from 0.2 to 3.0 g/g. The reaction temperature had the most eminent effect while the reaction pressure, resident time and H{sub 2}/oil ratio had little effect. A simulation model of hydropyrolysis was developed. It was clarified that reactivities of heavy oils could be predicted, utilizing this simulation model, from the ratio of saturated hydrocarbon to aromatic hydrocarbon in the oil. (21 figs, 3 tabs, 8 refs)

This paper presents the development of the tecnology of coal gasification combined cycle power generation, one of the important subjects of wide application of coal as the source of cost-effective energy which is supplied stably. The construction of plant, process and situation of development on the inside and outside of Japan are described. In Central Research Inst. of Electric Power Industry eight plans formulated from the construction of furnace and gasifying materials for it, coal feeding system and gas clean-up system are being evaluated by the multi-purpose evaluation method to select the optimum plan. A two chamber, two stage pressurized entrained bed gasifier and dry clean-up technology are being developed. In addition, the researches such as a metallic combustion furnace resistant to 1300{sup 0}C, ceramic gas turbine and technologies of components of gas turbine including the evaluation of serviceability of superalloy blade made of single-crystalline material are being actively conducted. (4 refs, 16 figs, 1 tab, 4 photos)

Raw coal, deashed coal and ash were mixed with phenolic resin and petroleum pitch. Each mixture was thermally treated at 1200, 2000 and 2800{sup 0}C. The effects of graphitizability of coal and ash content on the structural change were examined by transmission electron microscopy. The microstructure of Taiheiyo coal in composed of micropore phase that pores of 5 to 6 nm thick. The microstructure of micropore, lamella and mesopore phases formed from the micropore phase by the catalytic action of the ash. The microstructure of Yubari and Cerro coals are lamella phase in which the carbon lamination layers are selectively oriented. The graphitizability of Cerro coal is higher than that of Yubari coal. Since small quantities of macropore and mesopore phases are formed, the ash retards the graphitization of both coals. Mesopore phase is formed at a temperature of 1200 to 2000{sup 0}C owing to the pressence of the ash. (15 refs, 10 figs, 4 tabs)

The Electric Power Research Institute (EPRI) and the 3 plants are visited to study the present status of coal gasification in the U.S. There are 7 coal gasification plants in the U.S. EPRI says to place emphasis on 4 jet fluidized bed furnaces including Texaco furnace. The Cool Water Plant will be proof-tested up to 1989, meanwhile performing gasification of Australian coal according to the demand from Japan. The TVA Project is a Texaco quench type pilot plant of 200 ton/day which was operated up to 1985 while playing a pioneering role for coal gasification. The Great Plains Project processes coal at a rate of 14,000 ton/day using a fixed bed Lurgi furnace while proucing SNG at 3.5 million m{sup 3}/day.(1 fig, 1 tab, 3 photos)

The effective thermal conductivity of a packed bed of coal was measured by the hot wire method modified so as to be applicable to a continuous heating process. Measurements were carried out for binary or ternary mixtures of 11 kinds of coals as well as each coal at the heating rate of 0.05K/s and an apparent density of 85kg/ m{sup 3} from 300K. to 1200K. The effective thermal conductivities for packed beds of coals except Coal Cliff, Blair Athol and Akabira coals could be correlated by vitrinite reflection. The thermal properties of coal/coke obtained from temperature responses in a practical coke oven were studied with the thermal transfer model, considering fissures grown during coking. The estimated thermal properties varied with geometical configurations of ovens. (20 refs, 17 figs, 5 tabs)

Basic experiment for a gasifier using entrained bed, at a coal supply rate of 1 ton/d, is carried out. It is revealed that, from the result of the gasification test, the 1-stage gasification method cannot obtain simultaneously stabilized flow down of slag and high gasification rate. The 2-stage gasification method

can improve gasification efficiency while ensuring stabilized flow down of slag by selecting a suitable distribution ratio of oxigen and coal, despite an oxigen ratio. In addition, a suitable basic form of the gasifier is selected by quantitatively analyzing the fluidic characteristics of gas and particles using a normal temperature visible flow model. Various other study items reported herein, include the pulvelized coal supply system, slag tap, coal burner, refructries and collusion resistant material. A pilot plant of 20-50 ton/d can be basically designed referring to the results of these basic studies and elementary developments.(13 figs, 5 tabs, 4 refs)

A conception of development on the entrained bed coal gasification combined cycle power generation are reviewed. A pilot plant of 200 ton/d, to be launched from 1986, is required to have higher efficiency and lower cost than the overseas plans such as Cool Water Plan. The dry-feed air oxidation pressurizing 1-stage furnace is used as a kernel in view of better applicability to multiple types of coal, while additionally developing dry gas purification system and a 1300{sup 0}C class gas turbine. The gasifier technology is based on the results of technical development with the bench scale furnace. The dry gas purification and gas turbine technologies make use of the results sunshine project and private sectors.(12 figs, 4 tabs)

Development for the process development unit (PDU) of a coal processing rate of 5 ton/d and the pilot plant (PP) of 40 ton/d is described. Gasifieres for PDU and PP are the air pressurerized 2-stage fluidized bed types. Inner diameter of the furnace and the hight of fluidized bed are modified and tested by changing gasification conditions of PDU and PP. Various measures are concreted through such processes, including operating method, high-efficiency gasification conditions and improvement of furnace operability, resulting in a cold gas efficiency of 75% or above and a carbon conversion ratio of 95%. In addition, an integrated operation of the system has been performed toward a goal in 1987, including dry gas purification test and the elementary test for high temperature gas turbine, necessary keys for developing practical complex technology. The results will be further developed to design a larger plant.(9 figs, 2 tabs, 3 refs)

A 7000 m{sup 3}/d plant is developed aiming at producing highcalorie gas from coal. With this process, a mixed slurry of coal and heavy oil is fed to the fluidized bed reactor through a special pump, in which the slurry is gasified at 850-950{sup 0}C and 30 kg/cm{sup 2}G using oxygen and steam. The gasifier is a 1-column pressure type fluidized bed gasification system in which the slurry is thermally decomposed and char is partially oxydized. The temperature of the fluidized bed can be maintained higher than 900{sup 0}C because gasifier temperature is increased for higher reliability and efficiency, thereby achieving a target gasification ratio of 70%. Further more, the system can be continuously operated 500 hours by improving the nozzle and incorporating the coarse grain discharge mechanism. Complete measures, for preventing in-furnace nodules, are also established. Thus, the original objective of this theme is completed.(16 figs, 5 tabs, 1 photo)

Effect of ash on reaction rate is studied as a theme for higher efficiency of gasification. Using the test sample consisting of Taiheiyo coal char in the spheres of 5-6 mm diameter, the coal is gasified at a reaction temperature of 1,000-1,500{sup 0}C with a gasification agent of steam, revealing the following conclusions. At a temperature lower than 1,200{sup 0}C, ash layer is created around non-reacted carbon kernels. When the temperature is lower than melting one, the ash layer is diffused with rather small resistance. However, at 1,200{sup 0}C, the ash layer disappears from the surface of the kernel, reducing the diffusion resistance. At that time, the activation energy for interfacial reaction becomes about 1/2 of that at lower temperature range according to chemical kinetics. Addition of iron oxide flux greatly reduces the ultimate reaction ratio at 1,200{sup 0}C. (12 figs, 2 photos, 17 refs)

Effect of coal types, to gasification reaction speed, is studied. A reaction test, between the char of 13 coals and carbon dioxide and hydrogen gases, is

carried out to obtain weight reduction speed and surface change in residual char on the way of reaction. The results are systematically studied. Gasification reaction speed depends on the surface area change of the char under reaction and the structure of carbon. Reaction speed, beyond a reaction factor of 0.9 or above, becomes extremely small because of the structure of graphite created and grown during the reaction. Therefore, there is an optimum gasification condition for each coal type with a view to approaching carbon conversion ratio to 1.0. An optimum gasification equipment should be selected accordingly. (12 figs, 2 tabs, 17 refs)

The coal gasification equipment, using the entrained bed technology for contacting gas and solid particles, is studied aiming at conversion of coal to fuel gas and C1 chemical material. A coal gasification system, consisting of 1 column and 2 stages by combining the entrained bed and the fluidized bed of particles in upper and lower positions, is used for testing gasification of Taiheiyo Coal using gasification agents of air and steam and oxigen and steam in mixture. As a result, this system provides various features including that a gasification temperature, intermediate between the fluidized layer and entrained layer, can be introduced. In addition, the system can be stably operated. The fluidized layer, located in the upper part of this gasification system, obviously contributes to the improvement of carbon conversion ratio. (10 figs 1 tab)

The coal gasification furnaces have been improved so far in terms of coal processing quantity, better production gas quality and lower cost for production gas pressurizing power by raising temperature and pressure. A target pressure of the gasifier is 30 atm. Merit of the gasifier is not increased even with higher pressure. An optimum gasification temperature should be about 130{sup 0}C, an optimum reaction temperature for all furnaces. The gasifier are classified into 4 types of fixed bed, fluidized bed, spouted bed and fusion furnaces. However, the most suitable furnace is the wet ash type entrained bed gasifier as a gasification reactor for general coals in consideration of the application at about 1,300{sup 0}C assuming the establishment of molten slag handling technology. Furnace capacity will become 4,000-6,000 ton/d/unit for the spouted bed furnace. (15 figs, 2 tabs, 8 refs)

Liquefaction of Taiheiyo and Yallowrn coals using tar-sand bitumen and Venezuela crude oil as the solvent was investigated as a part of the study on the liquefaction of coal by heavier solvent using iron-based catalyst. The coal can be solubilized and decomposed by co-hydrogeneation of solvent and bitumen, hardly depending upon the types of bitumen used. The conversion for Taiheiyo coal shows the maximum at approximately 420{sup 0}C, while that for Yallowrn coal decreases exceeding 400{sup 0}C. The improvement of conversion in the co-processing varies according to the ranks of coal. The improvement for Taiheiyo coal is higher than that using tetralin, while that for Yallowrn coal is not made.(11 refs, 7 figs, 6 tabs)

NEDO surveys researches and developments in West Germany and the U.S.for coal liquefaction. In West Germany, Rheinische Braunkohle and Foeber Oel are visited. Foeber Oel retains 5 continuous test setups of 5 l/h each, looking for practical application. In the U.S., Pittsburgh Energy Institute, UOP, Exxon Research and Engineering and Shevron Research Engineering are visited. UOP maintains many continuous test setups of 100 - 120 cc/hour, mainly for comparing catalyzers and studying product performance. Shevron Research and Engineering is carrying out a study on 4 types of liquefied oils according to a request from DOE. There are abundant and significant study results in the world but not any decisive pattern at present.(1 fig, 1 tab)

Centering around USA and West Germany, the development of the coal liquefaction technology, one of the technologies concerning oil-alternative energy, is in positive progress and the examination through pilot plants have already been finished. The development projects and others in Europe, USA and Japan are reported here. Coal liquefaction projects in USA: There are two processes, namely the two-stage liquefaction process which aims at more efficient

liquefaction and the co-processing process intending the utilization of petroleum heavy oil. Coal liquefaction projects in West Germany: The KOHLEL process. The pilot plant was completed in 1981 and the excellent results have already been obtained in the scale-up technology. Coal liquefaction projects in Japan: The brown coal liquefaction process has been promoted as the Japan-Australia joint project and the development through small pilot plants are in progress about the bituminous coal liquefaction process, namely 1) the solvolysis process, 2) the solvent extraction process and 3) the direct hydrogenation process. (11 figs, 5 tabs, 22 refs)

It is known that the apparent viscosity of the slurry of coal particles and solvent varies with proceeding of the coal liquefaction reaction. The variation of apparent viscosity of the slurries of six ranks of coal and tetralin with proceeding of the liquefaction reaction was measured by a viscometer which can determine a viscosity ranging from 0.2 to 12 Pa.S at high temperature under high pressure. The result of comparising the data indicates that sharp viscosity change in the temperature rise and drop processes observed in the coal liquefaction of Akabira coal/tetralin slurry is also observed in the processes using Yubarishinko, Yallourn and Miike coals excepting Taiheiyo and Daido coals. The peak of viscosity of the slurry heated at the rate of 10K/min is observed at the time when the ratio by weight of quinoline soluble and benzene insoluble matters to benzene insoluble matters is 40% or more or the difference in the solubility parameters between quinoline soluble and benzene insoluble matters and the solvent is approximately 2{radical}(cal/cm{sup 3}) or more. (9 refs, 8 figs, 3 tabs)

The co-carbonization of solvent refined coal (SRC) and hydropyrene (CHP) was studied to use the primary coal liquefied oil as the carbon raw material. Needle-like coke was used as SRC and it was carbonized together with CHP in nitrogen gas of 5 kg/cm{sup 2}G. The carbonized SRC was mosaic coke, while SRC carbonized together with 40 to 60% of CHP at 500{sup 0}C for three hours showed anisotropic structure. The yield of coke to CHP is enhanced by the CO-carbonization of SRC and CHP. CHP carbonized under pressure is pitch-like coke which contains needle crystal in the anisotropic matrix. The chemical components of the pitch derived from hydropyrene were analyzed by the solvent extraction, gel-permeation chromatography and filed desorption mass spectroscopy to determine the chemical changes in the co-carbonization. The increase of coke derived from CHP is ascribed to the dehydrogenative condensation of SRC components into trimers and tetramers. (17 refs, 7 figs, 3 tabs)

The catalytic action of organometallic compounds such as Si, Ge and Pb belonging to the IVb group of Sn in the hydroliquefaction of coal was studied. The catalytic activity of organometallic compounds with alkyl- or phenyl-residue belonging to the IVb group in the coal liquefaction is in the order of Sn, Ge, Pb and Si. The catalytic actions of SiO{sub 2} and SnO{sub 2} are the same as that of organotin compound, while that of GeO{sub 2} is extremely low. The catalytic actions of butyl- and phenyl-germanium compounds are equal to each other independent of the organic residue. The catalytic activity is observed in the direct process from coal to oil in the liquefaction, while it is not observed in the three step process from coal through preasphaltene and asphaltene to oil. The catalytic active species obtained from organic germanium compound largely depends upon the pressure of hydrogen. (10 refs, 1 fig, 4 tabs)

The removal of metallic cations in brown coal by acetic acid and ammonium acetate was studied aiming at improving the reactivity of carbonization and liquefaction of coal. Calcium and magnesium ions in Morwell brown coal were able to be removed by the extraction with 1M ammonium acetate or 0.1M acetic acid solution. Although ferrous or ferric ion was not sufficiently removed, the carbonized substance modified by the carbonization together with pitch or hydrogenated material was able to be removed by that solution in the same degree as by 1N hydrochloric acid solution. The process using a weak acidic or neutral solution is practical even though ammonium remains in the coal to be treated in such a way that divalent cations are removed from the coal ranging from highly

carbonized coal to a certain coal to modify the carbonizability and to reduce the total ash content. The cation of acetic acid and wettability of organic acid to the hydrophobic surface of coal are effective for extracting the cations in coal.(15 refs, 11 figs, 4 tabs)

The coal liuquid by the solvent extraction of Taiheiyo coal was hydrogenated using Ni-Mo/Al{sub 2}O{sub 3} as the catalyst. The experimental result was compared with that obtained using CoMo/Al{sub 2}O{sub 3} catalyst. Carbonous substance deposited on the surface of recovered catalyst was investigated. The hydrogenation activity of Ni-Mo/Al{sub 2}O{sub 3} is so much higher than that of CoMo/Al{sub 2}O{sub 3} that a large quantity of a decalin type compound with saturated aromatic ring was produced. The denitrification does not sufficiently proceed even at 450{sup 0}C and there is no distinguished difference in denitrification between both catalysts. Although oxygen remained in the distilled oil in the whole range of temperature, most of the oxygen was removed from the distilled oil derived from SRC. Oxygen and nitrogen were concentrated into the carbonous substance deposited on the surface of recovered catalyst. It was found that the absorption of polar components containing oxygen and nitrogen mainly causes the deposition of carbonous substance on the surface of catalyst and deterioration of catalytic activity.(10 refs, 2 figs, 5 tabs)

The recycling solvent in coal liquefaction process was investigated. The liquefaction of Taiheiyo coal was carried out in a batchwise operation using fractional distillate of hydrogenated anthracene oil as the starting material. The result indicates that the light fraction in the recycling solvent is increased because hydroaromatic compounds are produced due to increase of light fraction in the hydrogenerated solvent itself with increasing of recycling times. Although the light fraction is increased till three times of recycling, it is hardly increased after that due to superhydrogenation of solvent itself, because the increase of hydrogen transferred by the hydrogeneration of recycing solvent is limited. Although the alkanes are accumulated in the recycling solvent even in the experiment, the production of them are as low as 1% or less even after four times of recycling. The function of liquefied solvent is sufficient though polycyclic hydroaromatic compounds containing polar group favorable to the coal liquefaction is hardly contained.(18 refs, 7 figs, 2 tabs)

The effect of benzene insoluble matters (BI) on the separation from the solvent was examined aiming at separating the insoluble residue from the coal liquid to which n-alkane with four or less carbon atoms as the anti-solvent was added. The experiment was made to investigate the separation of the benzene insolubles derived from different ranks of Taiheiyo and Moura coals from dilute dispersed system to which n-alkane with four or less carbon atoms as the anti-solvent is added. The result indicates that the sedimentation rate of Taiheiyo BI and Moura BI are so much increased by adding butane or propane gas with four or three carbon atoms that the addition is effective. The addition of methane or ethane gas with one or two carbon atoms affects hardly the separation of BI. The effect of separation of Moura BI by adding n-alkane is higher than that of Taiheiyo BI.(5 refs, 6 figs, 2 tabs)

Hydrogenation of aromatic compounds and hydrodesulphurization of the sulphur compounds were made in a small high-pressure differential thermal analysis apparatus operable even by a sample as little as 5 to 50 mg. Benzene was hydrogenated using stabilized nickel as the catalyst in such a way that the amounts of catalyst and sample were decided from the exothermic peak temperature. The reaction product was completely cyclohexane. Naphthalene was hydrogenated in the same way of experiment. The result indicates that the hydrogenation was completed, because the relationship between the reactant and the peak area was linear. In the hydrogenation of organic sulphur compound using molybdenum disulphide as the catalyst, the exothermic peak temperatures of these compounds are shown between 300 and 400{sup 0}C. Except for thiophene, the benzene ring in the product is not hydrogenated because of breaking of C-S bond in the hydrodesulfurization. (9 refs, 7 figs)

NEDOL Process, for liquefying bituminous coal, will contribute to stable supply of liquid fuels. The level of this technology will be equivalent to or even better than those in Western countries. Therefore, the Japanese government must proceed with the research and development with a pilot plant (PP) in time on the basis of the results of the basic study carried out so far, the fundamental and detailed design of the PP and knowhow accumulated in the relevant engineers. The Research and Development term of the PP will be extended 1-2 years unavoidably. However, the integrity of the entire plan should be maintained. Required scale for the PP is 250-280 ton/d under an image of the practical plant design. In addition, the advantage as a country of underdeveloping coal liquefaction should also be taken.

Mechanism and process of coal liquefaction are described. Using high-pressure hydrogen (100-300 kg/cm{sup 2}) with a 0.1 ton/d coal direct liquefying bench plant at a reaction temperature of 400-450{sup 0}C, preasphaltene of large molecular weight is created while producing subsequently asphaltene, heavy oil and light oil. In addition, it is revealed that the liquefaction reaction is classified into 2 reaction properties based on temperatures. Effective solutions for the slurry preheater and the pressure let down system, conventionary encountered in the coal liquefaction process, are found. In addition, effective knowledge on catalyzers and media oil, etc. are obtained for reasonable and advantageous liquefying reaction.(13 figs, 5 tabs)

A liquefaction experiment is performed using 4 types of coal having different coal ranks. The highest yield of product oil is with brown coal. Brown coal also brings about the largest phenols among the contents of product oil. The middle distillate of the liquefied oil is reformed by catalyzers Ni-Mo/Al{sub 2}O{sub 3} and CoMo/A1{sub 2}O{sub 3}. As a result, the former catalyzer contributes to higher yields of cyclohexane and methylcyclohexane, excellent in the hydrogen activity of benzene ring. The latter catalyzer brings about higher yield of toluene. Middle distillate of liquefied oil is mixed with light oil and used as fuel for the diesel engine. Revealed results include lower cetane number, slight increase of fuel consumption rate and increase of benzopyrene. The result of operating passenger car, with a fuel of octane number 91 for the gasoline distillate of liquefied oil reveals similar performance to conventional gasoline. (16 figs, 7 tabs, 2 photos, 19 refs)

Present status and forercast of the Japan/Australia joint brown coal liquefaction project is reviewed. The project is supported in technology and finance by Japan while Australia submitting crude brown coal and land, etc. A pilot plant, capable to process brown coal at 150 ton/d (50 tons in dry coal basis), has been constructed and operated by the Japan Brown Coal Liquefaction Co., Ltd., a subcontractor of NEDO, and its local cooporation in Victoria. The primary liquefaction process was completed in 1985, while also completing the secondary liquefaction process in 1986. Combined operation of the primary and the secondary is also continued. After completion of pilot plant operation, the plant will be operated by a target production of 15,000 ton/d x 6 lines, 100 barrel/d of liquefied oil. It appears that liquefied oil might become economically competitive against oil products around 2000. (4 figs, 2 photos)

In order to study the combustion rate and existing states of coke which would govern the temperature patterns in the sintering bed and resulting sinter properties, some quasi-granules of alumina particles and coke of different existing states which were modelled S(single) and P(pellet) types, were prepared and tested in a packed bed, and analyzed by applying the unreacted-core model. The existing states remarkablely influenced the rate of coke combustion and S type indicated very slow combustion rate compared with S' type (where alumina particles were not adhered to coke). When melting of adhered particles did not occur, the combustion rate could be estimated with the unreacted-core model. In the S type combustion, the width of combustion zone spreaded to the direction of higher zone at constant conditions, which meant expansion of higher temperature area, suggesting that coke existing states influenced also on pressure loss of the sintering bed. (9 refs, 14 figs, 2 tabs, 2 photos)

The process of anionization of coal by molten potassium under refluxing THF (tetrahydrofuran) as an analysis of coal followed by reductive alkylation by ethyl iodide was investigated. The anionizing reaction is accelerated by adding 18-crown-6 for the period of time as short as 0.5 hour, wherein approximately six ethyl groups per a hundred carbon atoms are introduced into the molecule of coal and 69 wt% of ethylated Yubari coal produced is solubilized. The reaction is, however, inhibited by the addition of potassium iodide. Such a phenomenon is affected by the molten potassium in THF and solvating electron. Thus, a chemical species dissolved in the solvent plays an important role. The cleavage of ether takes place preferentically by adding potassium iodide, while aromatic ring is effectively alkylated by adding crown. (16 refs, 2 figs, 6 tabs)

X-ray fluorescence method was applied to the analysis of sulfate and pyritic sulfurs contained in coal to establish the analytical method by comparing with the analytical data by ISO. The extraction process of sulfate and pyritic sulfurs in the X-ray fluorescence method is the same as that in ISO. Since sulfate and pyritic sulfurs collected on membrane filter are, however, analyzed by the X-ray fluorescence method, the subsequent procedure was able to be simplified. The samples of twenty three ranks of coal were analyzed by both X-ray fluorescence method and ISO. The result indicates that there is no significant difference between both analytical methods. The lower limit of determination in the X-ray fluorescence method is lower than that by ISO. The analysis of pyritic sulfur by the X-ray fluorescence method requires no reagents of heavy-metallic compounds such as tin, mercury and chromium used in ISO. (6 refs, 4 figs, 1 tab)

Since the total sulfur content of coal can be determined more effectively together with the other inorganic elements by the X-ray fluorescence method than by the other analyses, the validity of this method was examined. Determining the total sulfur contents of various ranks of coal from lignite to bituminous coal (strong caking coal), the X-ray fluorescence method was compared with the combustion IR method. The samples were prepared by powder press molding using aluminum ring. The elements requiring the correction of X-ray absorption are extended by using a simplified Berman and others' method. The result indicates that the X-ray fluorescence method is effectively used for the analysis of total sulfur content and the analytical accuracy is improved by the extension of elements requiring the correction of X-ray absorption. The X-ray fluorescence method can be applied to the coals containing 50% or less of ash.(7 refs, 1 fig, 2 tabs)

Cracked oils from heavy oil, oil shale and coal include much olefins of high reactivity. It is required to determine olefins contents because olefins cause coloring or gum. High performance liquid chromatography was used for analysis of olefins and the optimum concentration of silver nitrate was determined on the AgNO{sub 3} impregnated-silica column which was used for improving separation of olefins by connecting to a silica column. The optimum concentration when n-hexane was selected as a mobile phase, ranged from 0.2 to 0.4% to the dry weight of silica gel used as a carrier. When the column of this concentration range was used, olefins could be separated sufficiently from paraffins and diolefin of comparatively longer holding time could be separated from aromatics. And further recoveries of diolefin and cycloctene were considerably higher than those obtained by high concentration columns. (18 refs, 4 figs, 1 tab)

No.2 unit of Tomato-Atsuma Thermal Power Station began the commercial operation in 1985 as a 600 MW imported-coal fired power plant aiming at increasingly promoting oil backout and using diversified fuels. Improvement of efficiency by the investigation of economics making the best use of the effect of scaling-up and using various grades of coal as well as the new technologies such as supercritical pressure system, energy conservation and integrated automatic operation system have been adopted. The concentration of NOx in the exhaust gas is as low as 150 ppm or under without installing denitration facilities based on the new pulverized coal firing equipment for lowering NOx. The environmental measures such as the exhaust gas desulphurizer, electrostatic precipitator and

ash land fill site are sufficiently secured. The performance of this unit was confirmed by the test operation, firing identification test and experience of operation. The gloss thermal efficiency is on the highest level as much as 42.57%. The know-how on firing the imported coal has been accumulated. The unit is at present operated smoothly at a high rate for the base load to contribute to the stable supply and cost reduction. (12 figs, 5 tabs, 1 photo)

Fine fibers of vinylidene chloride are crimped and bundled forming spheres of 30 mm diameter as a filter material. Filtration test is performed with charged material quantities of 24, 32 and 50 kg/m{sup 2}, at a flow rate of 50 m{sup 3}/m{sup 2}.h. With a raw water SS concentration of 1.5-10 mg/l, removal ratios are 59, 72 and 81%, respectively. The filter material, after collecting suspended solids, is compressed but, after being backwashed, the material is inflated by the resilient force of the filter material while easily separating suspended solids. A small specific gravity of 1.7 for the filter material helps agitate the filter material by a small flow rate of backwashing air, thus suspended solids can be easily isolated through collision between the filter material and equipment wall and between the spheres of the filter material. The filter material provides higher void ratio, larger specific surface area and excellent adhesion onto the surface, which can assure larger removal rate of suspended solids and higher filtrating speed. (6 figs, 1 tab, 7 photos)

In order to establish countermeasures to prevent coal dust dispersion from coal unloading, transporting and storage facilities, the prediction technique and the preventing countermeasures were verified at Onoda Power Station of The Chugoku Electric Power Co., Ltd. The prediction formula of coal dust generation from the coal storage pile or coal unloading facilities was derived from wind tunnel and outdoor experiments, and the coal dust fall rate was predicted with the coal dust dispersion prediction program combined the prediction formula and the particle diffusion theory. As the preventing countermeasures, wind protecting covers and plates over the coal storage pile and coal facilities, and water sprinklers were equiped, adding to the operating instruction not to unload at strong wind condition( wind speed of min. 15m/s)and to keep surface moisture of the coal storage pile to min, 8%. From comparison of practical measurements with simulated values, the correlation coefficient over 0.8 could be obtained. After application of the countermeasures, the fall rate of coal dusts was lowered to about two third. (2 refs, 25 figs, 8 tabs)

In an attempt to drain a large volume of gas, a high-speed water jet is used to drill and enlarge a borehole so that cracks around the borehole will be expanded. Results of a series of basic tests show that craters and slits become deeper as the nozzle diameter and the jet pressure is increased. The depth of slits also increases with decreasing rate of delivery. The relations of the cutting depth with the distance (L) between the coal sample and the nozzle are examined, showing that the cutting depth increases with decreasing L. A study is made on the application of the system to practical cases. Results suggest that with a nozzle diameter of above 1.0 mm and a jet pressure of above 300 kg/cm, the system would be able to provide a borehole with a diameter of above 200 mm in Taiheiyo Coal Mine or one with a diameter of above 300 mm in Akahira Coal Mine. (4 refs, 20 figs, 4 tabs, 3 photos)

Coal circumstances, particularly an outline of coal resources exploitation in West Germany, France and U.K. is reported. In West Germany, test boring and physical survey have been performed in Ruhr coal mine in these 10 years by 466 shafts and an extension of 1,488 km, respectively. The French government predicts an estimated coal reserve of about 114 million tons and a most probable quantity of coal reserve of about 450 million tons according to a survey for ore reserve in Ruhr and Saar coal mines, etc. in a classification of economically acceptble shallow zone (500 m or less from the ground surface), medium deep zone, currently not competitive but soon becoming competitive (500 - 1,000 m) and deep zone where underground coal gasification can apply. Exploitation results in the U.K. in 1984 include 32 test borings and 312 km of physical

survey. Impressively, each country is making utmost effort to reserve own energy resource and recover economic competitiveness. (10 tabs, 2 photos)

Australia and New Zealand, sharing 46.7% of imported coal quantity in Japan, are surveyed for the assessment and comparison of major overseas coal supplying countries in view of long-term supply stability. Surveyed items include brief history of coal industry, outline of current status, national reserve quantity and mine property, coal qualities and grades, governmental policies and taxation for coal, environmental protection, procedures for the approval of new coal mine development, labor circumstances, export and domestic consumption, completion of infrastructure, calculation of exporting coal chain cost, etc. Australia retains superiority as a coal supplying country. However, labor circumstances must be watched. New Zealand retains coal reserve, although not abundant, of satisfactory quality level. However, modernization of coal mines are required together with modifications of socioeconimic infrastructure. (8 figs, 3 tabs, 3 photos)

The measurement of pulsation period of gas bubble generated from underwater explosion with a large amount of a insensitive explosive was tested by a microphone in air in place of piezo-electric gage in water. When the microphone was set near a explosion source, distinctly separated signals of repeated shock waves were obtained. When the microphone was set far from the source, signals were not clear and pulsation period could not obtained directly. But the pulsation period was evaluated from the self-correlation of recorded signals, which agreed well with direct measurements by a piezo gage. From the tests, the simple microphone technique was found to be able to use in place of the expensive piezo gage. (8 refs, 8 figs)

A scale model study on mechanical behaviors of the roof strata behind a longwall face is carried out and results obtained are discussed. In the model, the immediate and main roofs consist of laminated thin strata having a design strength. Results show that the roof behind a longwall face behaves like a beam. It undergoes initial fracture as the span exceeds a certain length. The failure progresses towards the upper beam elements as the face advances, and it reaches a saturated state when the goaf is filled with caved fragments. After this, the fracture proceeds steadily. Where the caving stays within the immediate roof, fracture occurs immediately behind the rear end of the face support as the support moves ahead. Where the caving reaches the main roof, fracture occurs periodically depending on the pitch of cracks across the main roof beam. Based on these findings, a roof model consisting of a beam and blocks is constructed to predict the caving angle and the self-supporting roof span up to the initial fracture. (10 refs, 13 figs, 2 tabs)

Major machines used in the working face include the shearer and the self-advancing frame. The shearer has been changed from the radio-controlled model to the microcomputer operated machine, while automating various functions. In addition, a system for comprehensively examining operating conditions and natural conditions in the working face for further automation. The selfadvancing frame has been modified from the sequence controlled model to the microcomputer aided electrohydraulic control system. In order to proceed further with automation and introduce robotics, detectors, control units and valves must be made smaller in higher reliability. The system will be controlled above the ground in the future, provided that the machines in the working face are remote controlled at the gate while transmitting relevant data above the ground from this system. Thus, automated working face will be realized. (2 figs, 1 photo)

TV camera and lighting for monitoring the working face, are developed for automating hydraulic coal mining. The ITV camera consists of a monochrome camera using Sony's CCD type solid state image pickup device after modification for the conformity to the intrinsic safety explosion-proof standard. In particular, the capacitor circuit and the switching regulator line are modified. Red LED is used for the lighting tool. The coaxial cable is incorporated for transmitting signals. Commercially available pressure-tight explosion-proof CRT is used to install in the air inlet side. Power to the ITV camera and the lighting tool is

supplied through a cable. The camera and the lamp are installed in the working face. The CRT and the power supply are mounted in the dewatering room about 300 apart from the working face. Transmitted image is used to monitor coal mining conditions at the working face, operable remotely. (4 figs, 3 tabs, 12 photos)

When planning coal customer's facilities and coal shipping port's ones, capacities of port facilities such as berth number, coal stockyard scale, capacities and number of loaders and unloaders, and required ship number, etc. must be determined. The simulation technique with a computer program was developed to solve these problems. When annual transportation requirements were given, optimal ship transportation capacity, number of ships, optimal stevedoring capacities at both export and import terminals, and navigation of coal carriers between both terminals could be estimated. This simulation technique is applicable to oil marine transportation and conventional physical distribution systems to investigate the capacity of facilities. (4 refs, 11 figs)

Fluidized bed combustors are commercialized as a technology to combust solid fuels with higher efficiency and lower emission and have functions of both combustion and simultaneous desulfurization and NOx reduction with dense phase fluidized beds but it is not so easy to realize these problems. The technology of circulating fluidized bed coal combustion is expected to offer potential break-through of various problems. But the details are not reported so far. Quantitative analysis of present situations was conducted and future problems were shown with officially available informations. This analysis includes the circulating rate and loading of solids, heat recovery and heat transfer rate as a function of loading of solids, the design of cyclones related to high solid concentration within the combustor, sulfur retention with reduced Ca/S ratio and problems related to NOx reduction to be developed in future. (51 refs, 23 figs, 8 tabs)

The pulverized coal fired boiler, constructed to substitute a heavy oil/pitch coke firing boiler is outlined in terms of features and operation results. This boiler is a single shell radiation type natural circulation boiler with an evaporation rate of 66 ton/h, steam pressure of 73 kg/cm{sup 2}G and a steam temperature of 485{sup 0}C. New trials and devices are incorporated in the coal pay-off system, mill equipment, combustion facilities and ash disposal equipment. Australian coal and domestic coal are fired in a ratio of 8:2 according to the optimum design based on various demonstration tests in addition to theoretical analysis. After being commissioned in December, 1985, the boiler has never been stopped operation due to trouble. No slugging or fouling have also occurred, while operating normally. (18 figs, 3 tabs)

A theoretical reaction model of combustion zone was developed on the pulverized coal injection(PCI) operation and numerical calculations were made to clarify characteristics of PCL operation and to compare those with practical measurements of all coke operation. PCI operation shifted distribution patterns of temperature and composition of gas in the raceway toward the tuyere nose but decreased the maximum temperature in the raceway. Such effects became particularly remarkable with increase of PCI rate. The increase of blowing temperature and pressure resulted higher volatization rate of volatile matter and higher gas temperature and shifted distribution of process variables toward the tuyere nose. The increase of volatile matter in pulverized coal had effects equivalent to increase of blowing temperature. At a operation with constant theoretical temperature, the distributuion of process variables was only varied toward the tuyere nose, while temperature was kept constant. (28 refs, 10 figs)

Trends of trade and development about coal up to 2000 are overviewed through long-term forecast in each industrial sector. An estimated total demand of coal in 2000 is about 143.62 million tons under an economical growth rate of 3.4% per year. The oil fired thermal plants have been converted to coal firing plants, while COM, CWM technologies entering substantially in practical stage. A total industrial demand will increase to about 15 million tons in 1995. Development of domestic coal will not grow due to high cost and poor fields. The demand of

imported coal will increase by 50 million tons from the level in 1983. It is preferable to participate in the exploitation of coal mines in overseas countries for mutual benefits. (1 fig, 5 tabs)

Adsorption equilibrium on quaternary ammonium resin in uranyl sulphate solution, which is similar to composition used in uranium hydrometallurgy, was studied by chemical equivalent method. In the given range, the ratio of HSO/sub 4//sup -/ to SO/sub 4//sup 2-/ on the resin is dependent on concentration of H/sup +/ and ionic strength ({mu}) of solution, but it is independent of other anions sorbed on the resin. When the solution has {mu} of 0.1 to 0.5, pH of 1.5 to 1.9 and 0.5 x 10/sup -3/ to 2.0 x 10/sup -3/ M of uranium, the value of n in complex UO/sub 2/(SO/sub 4/)/sub n//sup 2-2n/ is 2.5 to 2.7. The uranium occupies about 30% to 50% of total resin capacity.

A stable emulsion easyly appears, if acid leached solution from silicate uranuim ore containing more fluorite is treated by solvent extraction process. The relationship between formation of stable emulsion and silicic acid forms in solvent extraction has been studied by chemical analysis and electron microscope. It shows that the active silicic acid, intermediate polymerized silicic acid and silica gel can not lead to stable emulsion formation. The silicic acids of emulsion-causing are high polysilicic acids. The forms of various silicic acids in solution determine either the stable emulsion appears or disappears. If microamount of fluorine is present in solution, it will accelerate the polymerization of silicic acid to form high polysilicic acid. But, the over-amount of fluorine will depolymerize the high polysilicic acid to form active silicic acid. Aluminium and iron are complexed with fluorine and inhibit the effect of free fluorine in solution. The high polysilicic acid can be removed by adding polyether.

Some papers appeared recently, which are noticeable since they call attention to interesting experimental results referring to the old-dated question whether neutrinos are Superluminal (or not): but they diregarded most of the previous theoretical literature. We complement them, therefore, from the theoretical point of view; and add some experimental predictions that could be tested, especially in connection with neutrino oscillations. 32 refs.

A unified geometrical approach to strong and gravitational interactions has been recently proposed, based on the classical methods of General Relativity. According to it, hadrons can be regarded as black-hole type solutions of new field equations describing two tensorial metric-field (the ordinary gravitational field, and the strong one). In this paper, we first seize the opportunity for an improved exposition of some elements of the theory relevant to our present scope. Secondly, by extending the Bekenstein-Hawking thermodynamics to the above mentioned strong black-holes (SBH), it is shown: 1) that SBH thermodynamics seems to require a new expansion of our cosmos after its Big Crunch (i.e. that a recontraction of our cosmos has to be followed by a new creation); 2) that a collapsing star with mass M approximately in the range 3 to 5 solar masses, once reached the neutron-star density, could re-explode tending to form a (radiating) object with a diameter of the order of 1 light-day: thus failing to create a gravitational black-hole. 28 refs.

In substitution for Dirac monopoles with strings, we have recently introduced monopoles without string on the basis of a generalized potential, the sum of vector A and a psudovector *g*L5 B potential. By making recourse to the (graded) Clifford algebra, which just allows adding together tensors of different rank (e.g., scalars + psudoscalars + vectors + pseudovectors + ...), in a previous paper we succeeded in constructing a lagrangian and hamiltonian formalism for interacting monopoles that can be regarded as satisfactory from various points of view. In the present note, after having completed that formalism, we put forth a purely geometrical interpretation of it within the Kaeler algebra on differential forms, essential ingredients being the natural introduction of a generalized curvature and the Hodge decomposition. We thus pave the way for the extension of our monopoles without string to non-abelian gauge groups. The analogies of this approach with supersymmetric theories are apparent. 20 refs.

We describe the system we developed to test the linearity of wire chambers amplifiers of the muon spectrometer presently in construction for the L3 experiment at LEP. The system, controlled by an Apple II computer, is capable of localizing both defective components and faults in the printed board. It will be used to perform the large scale quality control of the amplifier cards.

It is pointed out how the quantum efficiency of X ray detection for CCD detecting system can be improved enlarging their sensivity range by means of heavy element converting structures. So the problem of fabricating CCD with a deep emptying layer is avoided.

The process of generating environmental externalities consists of three steps: industry generates residuals; residuals are transformed by the environment into ambient pollution; and pollution is 'consumed', producing disutility or damage. This paper is concerned with the transformation of residuals into ambient pollution, a subject that has received very little attention in the economics literature. It is showed how economic theory can be used to develop an aggregate relationship between residuals generation and ambient pollution in very much the same way that a production function summarizes engineering relationships of production. Restrictions on the functional form of such a pollution possibility frontier are developed. The frontier is estimated for the Petrified Forest region of Arizona.

Tests of important parameters of a food chain model showed that in the assessment of the radiation burden due to milk and meat contaminated as a result of livestock watering, attention should be devoted to the radionuclide content of water and the selection of the values of the following parameters: effective dose equivalent due to specific radionuclides, human consumption of milk, livestock water consumption, feed-milk transport coefficients for specific radionuclides, meat consumption, feed-meat transport coefficients, and the biological half-life of radionuclide excretion by livestock. The parameters relating to milk consumption are more significant that the meat consumption related parameters. (Ha).

The article describes a trip to the Sellafield reprocessing plant arranged by BNFL for journalists. The train journey from London and the actual tour round the Sellafield site and visitor centre are described briefly. Several protest groups were encountered on the way but the point made is that in encouraging visitors to the site and explaining what is going on there BNFL is trying to be more open in its dealings with the public in an effort to inform, reassure and lessen mistrust.

The former nuclear campaigner for Greenpeace, George Pritchard, explains why he resigned from Greenpeace. Although opposed to the nuclear industry he is committed to solving the waste problem created by it. Currently (1987) he is involved in a company which proposes a safe method of undersea disposal of nuclear waste. This scheme is expensive, but, the company claims, is safe for the environment and the public. The proposed method of disposal has not yet been made public.

The discussion centred round the need for the Society of Radiological Protection to educate children and the public in general as to the real hazards, and to provide real risk assessments for low level radiation. Papers given by employees of the nuclear industry, universities, the B.B.C. and informed laymen ranged from those on legislation and safety management to putting radiation risks into perspective for the public and research into determining public perception of risks from radioactivity in the nuclear industry and medicine.

The pro-nuclear lobby is accused of dubious tactics to promote their case for the Sizewell-B reactor. These include reassessing future electricity demand which, it is claimed, could only be met by nuclear power, claiming that new power stations were needed to avoid blackouts during cold spells, and the reporting of a major design fault in the control rods of the Torness and Heysham AGR stations. The latter is felt to be related to the promotion by the South of

Scotland Electricity Board of the AGR case, as opposed to the Central Electricity Generating Board's advocation of a PWR reactor design. The author argues for a series of coal-fired power stations instead, and a major energy conservation programme.

The Layfield report recommended that consent be given to allow construction of the pressurized water reactor at Sizewell in Suffolk. The implications for the process plant industry are considered. The total cost of the reactor is estimated to be Pound 1.6 billion, 95 per cent of which will be spent with British firms. The main exception are the pressure vessels to be made by Framatome of France. The Central Electricity Generating Board has already invested Pound 120 million in the development work for the plant. A further Pound 325 million will be allocated for the second phase, some of which has already been allocated for pipework, feedwater pumps and raw water treatment. A further 90 contracts including civil engineering have still to be placed. However, the benefits are seen to be not so much for the work directly involved at Sizewell-B but in the new programme of power station building which, it is expected, will follow. (U.K.).

The effectiveness of evidence presented by the Central Electricity Generating Board to the Sizewell-B Public Inquiry is considered. The CEGB had a monopoly of expertise in some areas to present its case, however, in many cases the CEGB evidence was rejected by the Inquiry Inspector, Sir Frank Layfield, and his assessors, in favour of the views of outsiders and objectors. One of the main tasks of the Inquiry was to assess the CEGB evidence to see if it was fairly presented. Extracts are taken from the Layfield Report on a number of topics where the CEGB had an information monopoly to see how successful the Inquiry team were in breaking into the monopoly. A second set of extracts are then taken to see how conflicting evidence was assessed on topics where CEGB did not have a monopoly of expertise. Two topics which are in between the competitive and monopoly situations are considered. These are 'other options', and 'social cost-benefit analysis'.

Public opinion about the building of a PWR power station at Sizewell-B is discussed, in particular, whether it will influence votes in a general election. Public attitudes, it is argued, have changed since the Inquiry, as a result of the debates at the Inquiry. The Government is trying to gain public acceptance by emphasising the number of jobs that Sizewell-B and the other planned PWR reactors will provide. However, it offers no compensation to local people living near the proposed sites. Even if public acceptance is gained, it may be that a PWR reactor is simply too expensive to build. Because of the low rate of return expected on capital invested it is not of interest to commercial companies. Indeed, privatisation is not seen as a possibility for nuclear power plants.

A summary of a lecture on 'The Big Public Inquiry' which raises questions about the precise role of the modern public inquiry, such as the Sizewell B inquiry, in a parliamentary democracy. It is concluded that ways must be found of combining efficiency with fairness, thereby ensuring that public inquiries are conducted so as to command respect and in an expeditious manner.

The paper reports on the proceedings of the public inquiry into the building of the European demonstration fast reactor fuel reprocessing plant (EDRD) at Dounreay, Scotland. This is the sixth and final report, and concerns mainly medical evidence and social/economic factors. The main issues discussed at the hearing were: health effects in the population around nuclear plants, including the incidence of leukaemia, radioactive waste management, transport of nuclear materials, provisions in the event of a major nuclear accident, and the effects of heavy metal discharges into the environment.

The effects of the Chernobyl reactor accident cannot yet be fully assessed. The one result that is certain however, is that the climate for nuclear power has changed permanently for the worse. Public opinion moved suddenly against nuclear power. The worldwide changes in policies in different countries are stated briefly. Assurances that a Cernobyl-type accident could not happen in the West

have not convinced everyone in the nuclear industry. The real problem of nuclear reactor safety is identified as that of safe operating and more particularly, that of proper man-machine interaction ie improvement of operator training and procedures. The problems with this are that the nuclear industry has to accept that improvements are possible and also, there is a limit to the extent to which human beings can be improved. Reducing the need for human intervention also has risks. The reactors operable and under construction at 31 May 1986 are listed. The Chernobyl accident has made everyone aware of the risks, and this will influence results of referenda on nuclear power (eg in Italy and Switzerland) and government energy policy decisions.

This article draws attention to a number of cases where it seems that scientists and technologists have been penalized in various ways for having views opposed to those of the nuclear industry. Attempts to encourage the general public to understand nuclear issues have also been discouraged, nuclear knowledge being kept as the preserve of the experts and policy makers, especially in the military applications of nuclear power. It may be that publications are suppressed or careers are destroyed. One example highlighted in the article is of Dhirendra Shama, a critic of India's nuclear policy, who was suddenly transferred from the Centre of Studies in Science Policy at his University to the School of Languages. Other examples are given from other countries - Australia, Britain, Canada, Federal Republic of Germany, India, Japan, New Zealand, Soviet Union, Sweden and the United States of America. The main 'crime' of those victimised is not in having critical views, but in alerting the general public to those critical view and ideas.

The public attitude towards the use of nuclear fission to generate electricity is discussed. Since the accident at Chernobyl, the risks of nuclear power are the main cause of public concern and in particular that the longterm effects are not fully known. The link that is commonly assumed between nuclear power and nuclear weapons is also an obstacle to public acceptability. Another is the lack of trust in government and, hence, in its policies. The contrast between the public attitude towards nuclear power in France and the UK is discussed. The key obstacle to a wider public acceptance of nuclear power is the public sense that remote, impatient people in remote, unaccountable corners of industry and government are making nuclear decisions which entail public risks. International safety standards may help but changes of emphasis are also needed if public confidence is to be gained.

The predominant energy issue at the 1986 Political Party Conferences was nuclear power, with the Chernobyl incident influencing the party policies. The Labour and Liberal parties strengthened their call for the phasing-out of nuclear power. The SDP and Conservative parties continue to support it. They were all in agreement about the need for lower levels of sulphur emissions from coal-fired power stations. The resolutions or motions passed at the conferences are given.

The attitude of the major political parties in Britain to nuclear power is described, based on the proceedings of the 1986 party conferences. The SDP are committed to major initiatives on energy efficiency, renewables etc but are still in favour of AGRs, the FBR and fusion. The Liberal Party Assembley reaffirmed its long-term opposition to nuclear power. The Labour party, whilst wanting to support a nuclear phase-out programme, recognised it could not do this in one Parliament. The Green Party, Plaid Cymru and the Scottish Nationalist Party are all basically anti-nuclear.

The British nuclear industry has set up a small group to tackle the problem of developing a Strategy to improve public attitudes towards nuclear power. The Nuclear Electricity Information Group (NEIG) aims to create a better public understanding of the basic issues and concepts involved in a nuclear power programme.

The paper reviews some of the problems of communication with the media and the public, as seen by the National Radiological Protection Board (NRPB), during the two weeks after the Chernobyl reactor accident. The role of the NRPB in handling

the radiation accident is summarized, including media relations, information supplied, public fears and radiation doses received.

Following the accident at Chernobyl, the nuclear policies of many governments have been reconsidered and restated. Those in favour of nuclear power are those with highly centralised state bureaucracies, such as France and the USSR, where public opinion is disregarded. In more democratic countries, where referenda are held, such as Austria and Sweden, the people have chosen to do away with nuclear power. Indeed, the author states that nuclear power represents the State against the people, the State against democracy. Reference is made to the IAEA Reactor Safety Conference held in September, 1986, in Vienna, and the declaration sent to it by AntiAtom International. This called for the United Nations to promote the phasing out of nuclear power facilities throughout the world. It also called on the IAEA to support the phasing out of nuclear power and promote benign energy forms instead.

Disquiet is expressed about the military implications of the research at CERN. Although the particle physics research is carried out for purely scientific reasons, there are inevitably technological implications which CERN either does not fully appreciate, or chooses to ignore. Collaboration between CERN and the Los Alamos Laboratory is mentioned and beam weaponry relying on accelerator technology developed at CERN, is given as an example of the military implications. The administrative structure of CERN is blamed for its reluctance to answer criticisms of this aspect, and also for its indifference to the opinions of those people living near its facilities. The author calls for CERN to be brought under proper democratic supervision and control.

The question how safe is safe is discussed. The way in which nuclear energy is presented in the context of the risks inherent in daily life is considered. Calculations based on actual reactor accidents (not Chernobyl) are then extrapolated for the proposed Sizewell-B reactor. Comparison is made between the risks of the nuclear industry and coal mining. Risk perception is considered and a risk index is constructed that allows for the fact that nuclear power continues to arouse public fear in spite of a good safety record.

This is the fifth compilation of annual reports for the Navy's ELF Communications System Ecological Monitoring Program. This report documents the progress of the following studies: Aquatic Ecosystems; Wetland Studies; Bird Species and Communities.

An enhanced-overpressure capless annealing technique suitable for annealing ion-implanted InP at temperatures of 900 C is described. The technique utilizes a Sn-coated InP wafer and is based on the same principle as the In-Sn-P liquid-solution method for eliminating InP surface degradation prior to epitaxial growth. InP samples implanted with 140-keV, 10{sup 14} power/sq. cm Si{sup +} and annealed at 900 C for 10 s exhibited improved electrical characteristics over samples annealed at 750 C for 5 min using conventional encapsulation techniques.

This second quarterly update to Risk Assessment, Management, Communication: A Guide to Selected Sources contains references gathered from the following databases: Toxline, Conference Papers Index, ENVIROLINE, National Technical Information Service (NTIS), Public Affairs Information Service (PAIS), ABI Inform, and Legal Resource Index. They cover the period from January through June 1987. The risk-update series is subdivided into three major sections: Assessment, Management, and Communication.

The report presents NBS' Center for Building Technology (CBT) publications for 1985-86. It is the tenth supplement to NBS' Building Technology Publications, and lists (CBT) reports issued during 1985-86. It includes titles of each CBT publication and those papers published in non-NBS media, keyword and author indexes, and general information and instructions on how to order CBT publications.

A literature search was conducted in the field of visibility using the term as a warning against stationary or moving hazards. The review was conducted to establish the extent of research conducted on the Visibility Index. The Index was designed to provide the method for examining the effective value of such properties as color, texture, pattern, contrast, and other variables which can be used to improve the effectiveness of warning devices, signs, labels, and markings aimed at providing increased safety through visible means. Future research was to be conducted in order to evaluate the effectiveness of increasing visibility as a means of reducing the hazard of a worker being struck or injured because he was not able to see a hazard in his path. References were cited for existing standards for visibility in the U.S. and foreign countries along with international standards. Other areas for which references were listed include current practices (air and ground transportation, safety clothing, underwater visibility, visibility measurement, and industrial and occupation applications), design factors (camouflage, pattern recognition, color contrast, luminance contrast, area, and reflectivity), and environmental variables (illumination, background, types of lighting, distance and moving targets).

Estimates of crop losses caused by ambient ozone are usually based on results from fumigation experiments performed on adequately watered crops. However, drought frequently affects crop growth, and moisture stress has been found to retard the appearance of ozone injury. To evaluate the effect of drought, a model was constructed that computes the influence of moistures stress on yield losses caused by ozone. The model was calibrated and run for soybean (Glycine max (L.) Merr.) using soil characteristics, weather, and ozone inputs from the Corn Belt states (Illinois, Indiana, Iowa, Missouri, and Ohio).

Summarized is a literature survey of the methods for joining ceramics to ceramics or ceramics to metals for high temperature applications. Also mechanical properties and potential applications of the joints are considered. The joining of ceramics is usually carried out by brazing or diffusion bonding. Especially the latter has been found useful, increasing the application of bonded ceramics. The possibility of using electron beam and laser beam welding for joining ceramics has also recently been investigated. The bonding of ceramics has found numerous applications typical for high operating temperatures, i.e., sensors and thermocouples.

This semiannual progress report covers the period from March 1, 1987 to September 30, 1987 under NASA grant NAG1-441 entitled Direct solar-pumped iodine laser amplifier. During this period Nd:YAG and Nd:Cr:GSGG crystals have been tested for the solar-simulator pumped cw laser, and loss mechanisms of the laser output power in a flashlamp-pumped iodine laser also have been identified theoretically. It was observed that the threshold pump-beam intensities for both Nd:YAG and Nd:Cr:GSGG crystals were about 1000 solar constants, and the cw laser operation of the Nd:Cr:GSGG crystal was more difficult than that of the Nd:YAG crystal under the solar-simulator pumping. The possibility of the Nd:Cr:GSGG laser operation with a fast continuously chopped pumping was also observed. In addition, good agreement between the theoretical calculations and the experimental data on the loss mechanisms of a flashlamp-pumped iodine laser at various fill pressures and various lasants was achieved.

The modeled cascade cells offer an alternative to conventional series cascade designs that require a monolithic intercell ohmic contact. Selective electrodes provide a simple means of fabricating three-terminal devices, which can be configured in complementary pairs to circumvent the attendant losses and fabrication complexities of intercell ohmic contacts. Moreover, selective electrodes allow incorporation of additional layers in the upper subcell which can improve spectral response and increase radiation tolerance. Realistic simulations of such cells operating under one-sun AMO conditions show that the seven-layer structure is optimum from the standpoint of beginning-of-life efficiency and radiation tolerance. Projected efficiencies exceed 26 percent. Under higher concentration factors, it should be possible to achieve efficiencies beyond 30 percent. However, to simulate operation at high

concentration will require a model for resistive losses. Overall, these devices appear to be a promising contender for future space applications.

An alternative class of photovoltaics was presented, which is designed to overcome two problem areas with conventional cascade designs: poor upper subcell performance and lossy intercell ohmic contact (IOC). It was shown that upper subcell quality can be improved by incorporating additional junctions into the upper subcell and that the problems with monolithic IOCs may be circumvented by using complementary pairs of three-terminal cells or a 1 x 2 voltage-matched configuration. Realistic simulations show that AlGaAs-GaAs and AlGaAs-InGaAs multijunction, multiband-gap solar cells (MJSC) may achieve benginning-of-life (BOL) one-sun, AMO efficiencies of 26 and 28 percent, respectively. Complementary cells made in the AlGaAs-InGaAs system can achieve BOL one-sun AMO efficiencies in excess of 27 percent. Seven-layer MJSCs are most advantageous for space applications due to their superior tolerance to radiation degradation.

Progress reports and technical updates of programs being performed by NASA centers are covered. Presentations in viewgraph form are included for topics in three categories: computer science, data systems and space station applications.

The Institute for Computer Applications in Science and Engineering computer science program is discussed in outline form. Information is given on such topics as problem decomposition, algorithm development, programming languages, and parallel architectures.

Progress reports and technical updates of programs being performed by NASA centers are covered. Presentations in viewgraph form, along with abstracts, are included for topics in three catagories: computer science, data systems, and space station applications.

Laser techniques are widely used for the diagnostics of aerodynamic flow and particle fields. The storage capability of holograms has made this technique an even more powerful. Over 60 researchers in the field of holography, particle sizing and image processing convened to discuss these topics. The research program of ten government laboratories, several universities, industry and foreign countries were presented. A number of papers on holographic interferometry with applications to fluid mechanics were given. Several papers on combustion and particle sizing, speckle velocimetry and speckle interferometry were given. A session on image processing and automated fringe data reduction techniques and the type of facilities for fringe reduction was held.

Ion chromatography (IC) has proven useful in analyzing chemical solutions used in the manufacture of multilayer circuit boards. IC provides results on ions not expected in the production solutions. Thus solution contamination, and breakdown products can be monitored in every phase of the circuit board manufacturing. During the first phase, epoxy laminates experience an etchback, first in chromic acid, which can be analyzed for trace chloride and sulfate, then in ammonium bifluoride/HCl, which can be analyzed for fluoride and chloride. Following a wet blasting to roughen up the surface, 20 {mu}in. of copper are deposited using an electroless bath. Again, IC is applicable for monitoring formate, tartarate, and sulfate levels. Next, an acid copper bath is used to electroplate the through holes with 0.001 in. of ductile copper. This bath is analyzed for trace chloride. Photoimaging is then performed, and the organic solvents used can be assayed for trace ionic chloride. Finally, a fluoroboric acid-based tin-lead bath is used to deposit a solderable alloy. This bath is analyzed for total fluoroborate, tin, and lead. In addition, mobile phase ion chromatography (MPIC) is used to monitor the nonionic organic brighteners in the baths. 11 refs., 3 figs.

A qualitative treatment is given of both single and multiple cavity wakefields, with the intent of providing some physical insight into the energy and bunch length dependencies. (LEW)

The activity of the Ca pump of inside-out vesicles of human erythrocyte membranes was studied using {sup 45}Ca and membrane filters. It was found that trifluoperazine completely inhibits the increase in the maximum activity of the Ca pump caused by the addition of calmodulin and has no effect on the calmodulin-stimulated increase in the affinity of the Ca pump for Ca{sup 2+}. A comparison of characteristic curves of the calmodulin-stimulated components of the activity of the Ca pump, inhibited and not inhibited by trifluoperazine, and the fluorescence intensity of N-phenyl-1-naphthylamine in the presence of calmodulin showed that the mechanisms of action of calmodulin on the maximum activity of the Ca pump and its affinity for Ca{sup 2+} differ significantly. In the first case the activation was due to the Ca-calmodulin complex and in the second to the calcium-free form of calmodulin. This conclusion is supported by data on the dependence of the activity of the Ca pump on the calmodulin concentration at low and saturating Ca{sup 2+} concentrations as well as by the results obtained in the case of moderate treatment of the membranes with trypsin.

A method is described for the isolation of cathepsin R from rat liver ribosomes, permitting a 264-fold increase in its specific activity in comparison with the initial level. The method of purification includes extraction of the enzyme from the ribosomes with 2-4 M LiCl and two-step affinity chromatography on Sepharose with immobilized soybean trypsin inhibitor and trypsin-Sepharose.

Electrical resistivity of Cr and Gd thin films (10 - 1500A) was studied in situ as a function of temperature, film thickness, and other preparation variables. The functional dependence of electrical resistivity of Cr thin films on thickness and deposition temperature is consistent with the size effect theories. Moreover, Cr films having thicknesses of 700, 800, 900 and 1000 A, prepared at 673 K at an evaporation rate of 1 A/sec, exhibit well-defined anomalies in the electrical resistivity vs. temperature curves associated with the spin-density wave-paramagnetic transition (T/sub N/). The value of T/sub N/ for 1000 A film is identical to that of bulk Cr. The temperature T/sub N/ first increases, reaching a maximum at about 800 A, and then decreases with decreasing thickness. These results can be interpreted in terms of tensile stresses present in these films. On the other hand, the thickness dependence of the electrical resistivity of Gd thin films deposited at 295 K exhibits anomalous peaks unless the utmost care is taken to exclude reactive background gases. Although the causes of the anomalous peaks could not be identified with certainty, it was observed that at greater thicknesses and better vacuum the films attained the bulk resistivity.

Protons and heavy ions were each used to generate charges (electron-hole pairs) within or nearby the sensitive volumes of different microelectronic test structures. Charge collection was measured in fully depleted (Surface Barrier Detectors-YAG444 photodiode) as well as partially depleted (N{sup -}, N{sup -} + N{sup +} GaAs Fat FET and UV100, YAG444 photodiodes) in junctions. The proton data were used to test the predictions of the CUPID code for fully and partially depleted devices. Enhanced charge collection at the edges of MESFET gates in GaAs were studied for different LET particles. A nearly linear relationship was found between the charge collection and the LET of the incident ions. The linear relationship is significant because it supports the assumption that one thickness can be used for the sensitive volume over a range of LET values. The effect of the surrounding material on charge generation within a well-defined volume was studied and founded to be small, for the dimensions studied.

Using ideas in mixture theory, a theory is proposed for the modeling of fluidized beds. The analysis is strictly limited to purely mechanical (isothermal) systems, and no chemical reaction or interconversion of mass takes place between the constituent. The mixture is considered to be made up of saturated granular materials infused with a classically linear viscous fluid. As a result of this formulation, we are able to derive an expression for a quantity often referred to as the solid pressure. The constitutive equations for the solid and fluid stress tensors, as well as the interaction (diffusive) force,

are made frame-indifferent. The theory is capable of predicting the behavior of the mixture in the two extremes. That is, in one limit, as the concentration of solid particles becomes small, the theory reduces to the classical theory of incompressible viscous fluid. In the other limit, as the effects of the interstitial fluid becomes negligible, the theory reduces to the flow of incompressible granular materials. The governing equations of motion are then made dimensionless, and the equations describing the lineralized stability of a uniform fluidized bed are derived. The importance of the dimensionless numbers and the need for further experimental and numerical studies are discussed. As an application of the theory, the equations describing pipe flows of saturated granular materials with appropriate boundary conditions are presented.

The patent concerns shields for nuclear reactors. The roof shield comprises a normally fixed radial outer portion, a radial inner portion rotatable about a vertical axis, and a connection between the inner and outer portions. In the event of hypothecal core disruption conditions, a cantilever system on the inner wall allows the upward movement of the inner wall, in order to prevent loss of containment.

Small angle neutron, as well as x-ray-scattering experiments have been performed with the metallic glasses Fe{sub 80}B{sub 20} and Fe{sub 80}B{sub 16}Si{sub 2}C{sub 2}. The amorphous ribbons were investigated in the as-quenched state and after relaxation anneals well below the crystallization temperatures where the materials undergo a ductile-brittle transition. The observed scattering effects reveal small structural inhomogeneities as well as extended fluctuations on a scale up to at least some thousand A, which both can be identified as concentration fluctuations. Inner surfaces or one-dimensional regions are suggested as sites for segregation of the metalloid atoms and impurities as well as sites favouring nucleation of crystallites. These processes, already taking place during the solidification, are enhanced by low temperature anneals, thus causing embrittlement of the amorphous material. 7 refs., 4 figs.

Continuous analysis of dissolved hydrogen disulfide in crude oil by atomization in nitrogen, separation of liquid aerosols on a columm packing avoiding fouling of filters.

Mercaptans are retained on metallic oxides which are regenerated by heating between 250 and 500/sup 0/C in an inert gas and treated by a gas containing oxygen and cooled in an inert cold gas.

Several rhodium complexes, maintained in the aqueous phase by the way of the water soluble ligand tris(m-sulphophenyl) phosphine or TPPTS, can catalyze the water-gas-shift reaction and the low pressure hydroformylation reaction of alkenes (8 bar, 80/sup 0/C). Particularly relevant are the acidic media (pH = 4.8) for the dinuclear species since turn over frequencies of 40 h/sup -1/ and selectivities of 95.8% in linear aldehyde were observed.

The overall focus of the book is on homogeneous catalysed processes which were seen to offer the most promising routes to C/sub 2/ oxygenates. The first three chapters review the industrial synthesis and applications of carbon monoxide such as in the manufacture of gasoline (e.g. Fischer-Tropsch, Mobil processes), organic chemicals (e.g. ethanol, acetic acid, etc.), industrial importance of C/sub 2/ oxygenates, and use of methanol as a future feedstock are discussed. The next six chapters are each concerned with the production of a particular C/sub 2/ oxygenate and a detailed analysis of the methods and catalysts used. The hydrocarbonylation of methanol occupies a large chapter (136 references) with a comparative examination of the catalysts available, and their modification to increase selectivity to either acetylaldehyde or ethanol. Following chapters examine the synthesis of ethyl acetate, acetic acid, acetic anhydride, vinyl acetate, ethylene glycol and oxalic acid.

We have studied the structural and optical properties of CuInS/sub 2/ thin layers prepared by airless spray. The X-ray diffraction analysis showed that these layers are well crystallized with (112) principal orientation which is

clearly privileged for a concentration ratio (Cu(I))/(In(III)) = 1 in the pulverization solution. The value of the gap, of the order of 1.45 eV, was obtained from transmission and reflection optical measurements. The values of open circuit voltage and short circuit current of CdS/CuInS/sub 2/ cell are respectively of the order of 0.3 V and 2.7 mA.cm/sup -2/.

Photocells are made with 200 {mu}m thick wafers cut out of Polyx ingot. N/sup +/P mesa diodes are used in order to do local investigations. Then the investigated samples are annealed in hydrogen gas flow at 280/sup 0/C during 4h. The treatment improves neatly electron diffusion lengths, photocurrents and photovoltages.

The crystal structure of Ba/sub 2/ YCu/sub 3/ O/sub 8-{delta} at 20K and 298K has been determined by single-crystal neutron diffraction. In contrast to the superconducting orthorhombic phase for which {delta}4a1.1, this phase crystallizes in tetragonal space group. The increase in oxygen vacancies compared to Ba/sub 2/ YCu/sub 3/ O/sub 8-{delta} is confined entirely to the sites in the plane midway between pairs of closest barium atoms. No significant differences were observed between the structures at 20K and 298K.

The sources and distribution of polycyclic aromatic hydrocarbons were characterized in six surface sediments from Port Cros (France). Aromatic hydrocarbon levels range from 3 to 59/sub {mu}g.g//sup -1/ dry material. Polycyclic aromatic hydrocarbons derived mainly from combustion sources: natural combustion (forest fires, burning land plants) and anthropogenic combustion (fossils compounds). Petroleum and naturally derived aromatic hydrocarbons were also found.

Individual papers in these proceedings are abstracted separately. (LEW)

The reports in the study were processed separately for the data bases. Research involved attempts to improve PET imaging and diagnostic techniques in man. The primary radiopharmaceutical used was a form of fluorodeoxyglucose. (TEM)

We developed a rapid analytical procedure for 2-fluorodeoxyglucose (2FDG) based on the use of the commercially available isolated-enzyme hexokinase, which has several advantages over chromatographic analysis, especially for the new generation of turn-key PET centers. In the new synthetic procedure the new analytical method is particularly suitable for interfacing with an automated synthetic unit. We refined our procedure, based on generation of fluorotri-methylsilane, for recovering unreacted F-18 from reaction mixtures, which is extremely useful for obtaining F-18 for exploratory work. 2 figs., 1 tab.

This project developed routine procedures for the preparation of radiotracers that would be useful probes for the CNS dopaminergic system. We have previously prepared and evaluated Br-75 (or Br-76) labelled analog of SCH 23390, a selective D1 receptor antagonist. Because of the relatively rapid pharmacokinetics of SCH 23390, C-11 was also found to be adequate. The synthesis of C-11-SCH 23390 was recently reported and we have performed in vivo experiments to further evaluate C-11-SCH23390. 2 figs., 2 tabs.

More extended EM algorithms that incorporate various physical and statistical physical factors affecting quantitative measurements in tracer kinetic studies have been developed. Factors that have been considered include Poisson process of photon emission, physical decay, photon attenuation, random coincidence and scattered radiation. Computer codes for estimating cerebral blood flow based on various steady-state and rapid administration techniques using oxygen 15 labeled CO{sub 2} or O2 have been completed. Preliminary results indicate that the bolus water injection method is perhaps the first method of our choice for protocol implementation. Software development for blood volume studies using CO is nearly complete. We have developed a method based on computer matching of surfaces as identified in multiple imaging scans which allows registration of any number of scans from single or multiple modalities.

A comprehensive model describing the response of the steady-state tissue distribution of glucose to changes in plasma glucose concentration was developed. In the model, the steady-state glucose content can be used to predict the steady-state distribution spaces of both phosphorylatable and non-phosphorylatable glucose analogs, and thus the value of the lumped constant (LC) required to convert measured rates of analog metabolism to the desired rate of glucose metabolism. Models of the sensitivity of the kinetic rate constants for phosphorylatable glucose analogs to tissue glucose content were developed. The use of the measured distribution space of a non-phosphorylatable analog such as methyl glucose as an indicator of the LC, is only useful for hyperglycemia. We determined that a particular aspect of the kinetics of phosphorylatable analogs, the ratio of the phosphorylation rate constant to the membrane transport rate constant, is very sensitive to glucose content over the entire physiological range of values. Considerable effort is being made to optimize the use of venous blood that is "arterialized" by limb warming methods. Similarly, final refinements have been made to the non-linear least squares fitting routines, allowing for blood-borne radioactivity and for the loss of phosphorylation product.

The effects of changes in serum insulin and glucose on brain glucose metabolism using PET technology were investigated. Eight normal, right-handed, male subjects were studied on three separate occasions at least one week apart. In each subject a PET scan was performed under three different metabolic circumstances: basal conditions after an overnight fast, euglycemic clamp, and hypoglycemic clamp in which the plasma glucose was maintained at 55 mg/dl. Exogenous insulin was infused at the same rate in the euglycemic and hypoglycemic clamp studies. In the latter study, the concomitant glucose infusion rate was reduced to allow the plasma glucose concentration to fall to the desired level of mild hypoglycemia. During each study, dynamic positron emission tomography was used to characterize cerebral uptake and distribution of the Fluorine-18 2-deoxyglucose radiotracer as a function of time. Analysis of the brain uptake curve and tracer input function provided rate constants for transport and phosphorylation in accord with a 3 compartmental model (Sokoloff, 1979). Dynamic scans were performed on each study occasion allowing individual rate constants to be studied. In addition to the brain uptake curves, plasma glucose, F-18 2DG levels and counterregulatory hormone values were determined from frequent arterialized venous blood samples.

This report describes progress in understanding the cognitive function in man. One study attempted to distinguish psychiatric patients from apparently normal individuals based on their metabolism of fluorodeoxyglucose (FDG) by the frontal cortex of the brain. Another study tested the uptake of FDG in apparently normal individuals performing designated tasks. A third study matched the uptake of FDG in Alzheimers patients with apparently normal control patients. The results of additional case studied are mentioned. (TEM)

We have proposed to use H{sub 2} {sup 15}O and 2FDG to monitor changes occurring in human cerebral gliomas as a consequence of radiation therapy with neutrons or photons. Our specific aims are to characterize oxidative metabolism of glucose in human cerebral gliomas, and to relate observed changes as sequelae of radiation therapy with neutrons or photons. We correlate 2FDG studies with subtle neuropsychological changes induced by radiation treatment of nominally normal brain parenchymal tissues through the use of the instrument developed at this center to study presenile dementia or Alzheimer's disease. It has long been recognized that whole brain radiation treatment can bring about a nonspecific dementia. Coordination of PET studies and careful behavioral evaluation will elucidate this problem.

Nonuniformities in porosity or binder distribution in green-state ceramic compacts can lead to failure in the final densified material. NMR imaging is a nondestructive characterization technique, most commonly used in medical diagnosis, which we have adapted for the production of tomographic images of porosity and of binder distributions. We measure open porosity by the imaging of

a suitable filler fluid introduced into the part by vacuum impregnation. Our results on partially sintered bodies show rough correlations with predicted porosity distributions. Binders with a high content of plasticizer may be imaged directly. Binder distributions with a plasticizer weight percent typical of those used in cold-pressing and injection molding cannot be imaged with conventional clinical or animal research instrumentation and methods. We have been successful in imaging such binders directly. We present results illustrating our techniques in a series of green-state and partially sintered aluminas. 26 refs., 12 figs., 1 tab.

Silicon with buried oxides formed by ion implantation (SIMOX) or zone-melt recrystallization (ZMR) was exposed to deuterium gas at temperatures from 773 to 1273{sup 0}K, and the depth profile of the D was then determined by nuclear-reaction analysis. The D was distributed through the buried oxide, with no measurable quantity in the Si phase. Uptake was controlled by permeation through the Si overlayer, and the permeability of D in Si was determined at 873{sup 0}K. The sample dependence of D uptake indicated substantially fewer defect-trap sites in SIMOX oxide annealed at 1678{sup 0}K as opposed to 1548{sup 0}K, with still smaller defect densities in the ZMR oxide. Hydrogen exposure at 1273{sup 0}K substantially disrupted the SIMOX structures. 6 refs., 5 figs., 1 tab.

A small value of the coherence length and the Fermi energy allows one to consider a new high T/sub c/ superconductor as a strongly correlated state. An analysis of the experimental data (La/sub 1.8/Sr/sub 0.2/CuO{sub 4}) leads to the conclusion that high T/sub c/ is provided by the coexistence of the phonon and non-phonon (plasmon) mechanisms of superconductivity. 20 refs.

This paper presents some results of a program in which the characterization and control of interfacial bonds in composites are being investigated. The General Purpose Powder Diffractometer (GPPD) at the Intense Pulsed Neutron Source (IPNS) have been employed to measure residual strains in Al{sub 2}O{sub 3}/SiC, ceramic-ceramic composite by neutron diffraction techniques from which stresses at the fiber-matrix interface may be calculated. Results of this experiment and initial results employing ultrasonic techniques to assess whisker-matrix bonding are discussed. 9 refs., 5 figs.

NbN films have been shown to be good candidate conductors for high field superconducting magnet applications. This paper examined various preparation techniques which could enhance the critical current density J/sub c/ and upper critical field H/sub c2/ of NbN films made by magnetron sputtering. Decreasing film thickness to reduce average grain diameter had little or no effect on J/sub c parallel/, but did increase J/sub c perpendicular/. Layering NbN with thin insulating layers of aluminum nitride resulted in significant increases in J/sub c parallel/.

A new computer code SPECOMP has been developed to calculate displacement damage for compound materials. The code uses primary recoil atom energy distributions from the SPECTER code and thus requires no access to nuclear data bases. For each combination of recoil and matrix atom, the code determines the secondary displacement functions and integrates over the recoil energy distributions. The net displacements for a compound is then the weighted sum of all combinations of atoms in the compound. Calculations have been completed for fusion breeders, insulators, and alloys (Li{sub 2}O, LiAlO{sub 2}, Al{sub 2}O{sub 3}, SiO{sub 2}, V-15Cr-5Ti, 316 ss, Nb-Ti, TaO). In cases where there are large mass differences between the atoms in the compound, the damage calculated by SPECOMP is significantly different than the weighted sum of elemental damage from SPECTER. Displacement functions for various materials are being added to the SPECTER package for routine use; however, users of SPECTER can easily perform calculations for new compounds. 6 refs., 2 figs., 1 tab.

The Sixth Status Report comprises experimental results which expand on the quenching effect of iron in the UP-91 glass matrix doped with 5.0 x 12{sup 20} neodymium ions per cm{sup 3}. The effect of iron on quenching as a function of neodymium content in UP-91 is also investigated. The dopant level of iron for

this study is chosen to be 300 ppMw Fe. Plots of the 1st e-folding time, ln 1st e-folding time and decay rate as a function of iron impurity input at a fixed Nd concentration and Nd concentration at a fixed Fe input are included. Also plotted on all graphs is the OH absorption coefficient at 3.5 {mu}m for each melt which monitors OH contamination level. 32 tabs.

Functional compartments of fast and slow twitch fibers have been observed by {sup 31}P-NMR spectroscopy during exercise of the wrist flexor muscles in a sedentary, young male subject. Values of Pi, phosphocreatine (PCr) and adenine nucleotides were determined at rest and during an exercise protocol. The subject flexed his wrist muscles at 20% of maximum strength every 5 sec for 6 min and then increased his effort in the next two 6 min intervals to 40% and 60% of maximum. With exercise, the Pi/PCr rose rapidly to the exceptionally high value of 2.2 at 60% effort. As the Pi increased, the initial single peak (pH 7.0-6.9) split into two distinct components with pH values of 6.8 and 6.3. Quantitatively, distribution of the Pi was 40% in the pH 6.8 peak and 60% in the pH 6.3 peak as determined by area estimation following curve fitting. This presumably reflects two pools of Pi corresponding to the oxidative (slow twitch, high pH) and glycolytic (fast twitch, low pH) fibers. In the second identical exercise sequence which followed immediately, only one Pi peak (pH 6.8-6.9) appeared. This suggested that the glycolytic contribution to energy production was largely exhausted and the residual energy was derived from oxidative metabolism. During exercise at high levels, total phosphate decreased due primarily to loss of NMR visible adenine nucleotides. Similar phenomena have been observed in three other sedentary individuals, but not in trained athletes.

The ability of rat serosal mast cells (MC) to release superoxide (O{sub 2}{sup -}) upon activation by immunologic and nonimmunologic stimuli was investigated. Purified MC (90-95%) were either sensitized with monoclonal IgE reactive against dinitrophenyl bovine serum albumin (DNP-BSA) and challenged with DNP-BSA, or naive MC were treated with compound 48/80 or ionophore A23187. O{sub 2}{sup -} release was measured by O{sub 2}{sup -} dismutase (SOD)-sensitive reduction of cytochrome C and MC activation was assessed by the release of histamine or [{sup 14}C]5-hydroxytryptamine (5HT). The results reveal that activation of MC by 48/80 or immunologic challenge does not release O{sub 2}{sup -}, although these stimuli induce substantial release of histamine and 5HT (40-70%). In contrast, A23187 released O{sub 2}{sup -} (3-6 nMols/10{sup 6} MC) and histamine (40-80%). In mixed cell preparations containing MC and macrophages (M0), activation of MC with 48/80 resulted in inhibition of M0 O{sub 2}{sup -} release. The MC-mediated inhibition of O{sub 2}{sup -} production was not due to histamine or 5HT, but was due to MC-granule SOD. MC contain abundant quantities of SOD and, therefore, release O{sub 2}{sup -} only when its production exceeds the intracellular SOD threshold following activation with selective stimuli. In addition, the apparent differences in the mode and site of action of various stimuli on MC may contribute to the discriminative release of O{sub 2}{sup -}.

The activity of the Na/K/Cl cotransporter in smooth muscle cells cultured from rat aorta was assayed by measuring the initial rate of furosemide-inhibitable {sup 86}Rb influx or efflux. Five uM furosemide or 0.2 uM bumetanide inhibited influx by 50%. Furosemide-inhibitable {sup 86}Rb influx depended on the presence of all 3 ions in the external medium. The dependence on Na and K was hyperbolic with apparent Km values of 45 and 5 mM, respectively. The dependence on Cl was sigmoidal. Assuming a stoichiometry of 1:1:2 for Na:K:Cl, a Km for Cl of 60 mM was obtained from a Hofstee plot of the data. Rapidly growing cells had 3 fold higher cotransport activity than quiescent cells. Angiotensin II (ANG) stimulated furosemide-inhibitable {sup 86}Rb efflux by 2 fold. An ANG receptor antagonist prevented ANG from increasing cotransport activity. Two calcium ionophores, A23187 and ionomycin, increased cotransport activity by 2 fold. Phorbol myristate acetate had no effect on cotransport activity. Isoproterenol, dibutyryl cyclic AMP, cholera toxin, or methylisobutylxanthine inhibited furosemide-sensitive {sup 86}Rb influx by 35 to 50%. From these findings they conclude that increasing cytoplasmic free calcium stimulates cotransport activity, whereas increasing cellular cyclic AMP inhibits the cotransporter.

The authors cultured smooth muscle cells from rat aorta and assayed Na/Ca antiport by measuring the initial rate of {sup 45}Ca influx in Na-loaded cells. Na/H antiport was assayed by measuring the initial rate of {sup 22}Na influx in acid-loaded cells. The external medium was the same for both assays except Na was 10 mM for Na/H antiport and O for the Na/Ca antiport assay. The dose of each congener that caused 50% inhibition (I{sub 50}) was calculated using a log-log median effect plot. The linear regression coefficients ranged from 0.916 to 0.998. Of all the compounds tested only dimethylbenzamil is more potent as an inhibitor of Na/Ca compared to Na/H antiport.

Cultured smooth muscle cells from rat aorta were loaded with Na, and Na/Ca antiport was assayed by measuring the initial rates of {sup 45}Ca influx and {sup 22}Na efflux. The replacement of extracellular Na with other monovalent ions, usually N-methyl-D-glucamine (NMG), was essential for obtaining significant antiport activity. Mg competitively inhibited {sup 45}Ca influx via the antiporter (Ki = 100 uM). External Ca stimulated {sup 22}Na efflux as expected for antiport activity. Mg did not stimulate {sup 22}Na efflux indicating that Mg is not transported by the antiporter. Mg inhibited Ca-stimulated {sup 22}Na efflux as expected from the {sup 45}Ca influx data. The stoichiometry of the antiporter was calculated from the changes in the rates of {sup 45}Ca influx and {sup 22}Na efflux at 3 Mg concentrations: 2.87 +/- 0.25 (mean +/- SE, n=5). The replacement of external NMG with potassium, but not other monovalent ions (choline, Li), decreased the potency of Mg as an inhibitor of Na/Ca antiport by about 6 fold. Other divalent cations (Co, Mn, Cd, Ba) inhibited Na/Ca antiport and high external potassium decreased the potency of each by about 6 fold. The order of effectiveness of the divalent cations as inhibitors of Na/Ca antiport (Cd>Mn>Co>Ba>Mg) correlated with the crystal ionic radius of the cation.

Under basal conditions Cl{sup -} efflux from human fibroblasts occurs with a rate constant of permeability of 0.08 min{sup -1}. 50% of the basal efflux is due to Cl{sup -}/anion exchange and is DIDS inhibitable, 25% is due to Na{sup +}/K{sup +}/Cl{sup -} cotransport and is furosemide inhibitable, and 20% is due to an electrically conductive pathway. Increasing intracellular Ca{sup ++} with A23187 stimulates Cl{sup -} efflux by 30%. This increase appears to occur entirely via an electrically conducting pathway, but unlike basal Cl{sup -} conductance, it is DIDS sensitive. Exposure of the cells to dibutyryl cAMP stimulates Cl{sup -} efflux by 15%. They do not yet know whether the cAMP stimulated pathway is electrically conductive, but the stimulation is additive with that caused by elevated Ca{sup ++} suggesting that different pathways are activated. Elevation of intracellular pH by any of several standard methods increases Cl{sup -} efflux by as much as 700%. The pH effect appears to be mediated by a Cl{sup -}/anion exchange pathway since it is DIDS sensitive and electroneutral. Previous work from this laboratory describing a transient rapid efflux of Cl{sup -} followed by a slower efflux phase can now be explained as the result of a transient alkalinization of cells rather than as 2 subcellular Cl{sup -} compartments. This alkalinization occurs when cells are transferred from a 5% CO{sub 2} atmosphere during {sup 36}Cl{sup -} load to ambient CO{sub 2} for efflux.

Hepatocytes have been shown to possess a sodium-dependent and sodium-independent bile acid transport system. Photoaffinity labeling studies have identified the carrier proteins as two intrinsic membrane components (54 kDa and 49 kDa) located on the sinusoidal surface domain. These proteins were also labeled by DIDS which is a potent inhibitor of hepatocyte bile acid transport. These two proteins have been significantly co-purified by affinity chromatography and subsequently utilized as an immunogen for the production of monoclonal antibodies. Spleen cells from immunized SJL-J mice were fused with SP2/0 Ag 14 myeloma cells and the resulting hybridoma colonies screened by ELISA and immunoprecipitation assays. Colonies producing antibodies against these proteins were cloned and IgG mabs purified from ascites fluid on a protein A-Sepharose column. Several mabs were shown to bind to a 49 kDa protein on the surface of intact hepatocytes, which was one of the proteins labeled by DIDS. The binding

of one of these antibodies (25A3) to hepatocytes resulted in a substantial protection of the Na{sup +}-dependent bile acid transport system from inhibition by DIDS. Binding studies with {sup 125}I-25A3 indicated that this bile acid carrier comprised approximately 1% of the total membrane protein. These results establish that a 49 kDa protein in hepatocyte sinusoidal plasma membranes is a component of the sodium-dependent bile acid transport system.

Biochemical processes involved in the movement of copper (Cu) into and out of the yeast Saccharomyces Cerevisiae have been investigated. Overall uptake of Cu was measured by disappearance of Cu from the reaction mixture by atomic absorption sensitive to 10{sup -10}M. The process of Cu influx is composed of a prerequisite binding and subsequent transport. The binding is non-energetic but is competitively inhibited by zinc(Zn). Transport is energetic as shown by an increased influx in the presence of added glucose. This process is prevented by 2,4-dinitrophenol(DNP). Cu influx is accompanied by an exchange for potassium(K) in a ratio of K:Cu=2:1. The process of Cu efflux involves a second type of binding site, probably of low affinity but large capacity. The presence of glucose causes the binding of extracellular Cu to these sites in a non-energy-dependent mechanism which prevents Cu efflux. Zn does not compete. DNP has no effect. The K:Cu ratio of 4:1 observed in the absence of glucose suggests a lowered net Cu uptake as a result of concomitant efflux activity. Finally, in the absence but not the presence of glucose, the pH of the extracellular solution increases. These observations are consistent with the idea that (a) yeast membrane has two Cu-binding sites, one of which participates in influx and one in efflux; (b) Cu exchanges with K during influx and with protons during efflux.

Copper is an essential metal that is highly concentrated in the brain. The blood, the sole source of tissue Cu, contains 16-20 {mu}M Cu, of which >95% is complexed to proteins and <5% to peptides and amino acids, primarily His. They addressed the question: what is the mechanism(s) for Cu uptake in the brain? The initial rates of 67-Cu uptake by hypothalamic tissue slices obtained from adult male rats were evaluated in vitro. Uptake of Cu(His){sub 2} was 10 times greater than that of CuAlbumin or Cu(II). Within the range of 0.2-150{mu}M Cu, multiple uptake sites for CuHis were apparent. Increasing the molar ratio of His:Cu had a differential effect on Cu uptake: enhancing uptake at [Cu] <1 {mu}M and suppressing uptake at [Cu] >1 {mu}M. Thus, using a His:Cu ratio of 1000, they observed a high affinity process exhibiting saturating and half saturating values of 5 {mu}M and 1.5 {mu}M Cu, respectively; using a His:Cu ratio of 2, they observed a low affinity process exhibiting saturating and half-saturating values of 100 {mu}M and 40 {mu}M Cu, respectively. Both processes required thermic but not metabolic energy, suggestive of facilitated diffusion. Considering the blood brain barrier for proteins, CuHis appears to be the major substrate for Cu uptake by neuronal tissue. They demonstrate the existence of a ligand specific, high affinity (apparent Km about 1.5 {mu}M Cu) uptake process for CuHis in the brain, operative at the physiological concentration range of CuHis and histidine.

Uptake of {sup 3}H-choline was studied in granular pneumocytes isolated from rat lungs by tryptic digestion, attached to Nucleopore membranes coated with rat-tail collagen, and maintained in primary culture for 24 hours. 3-0-Methyl-[{sup 14}C]-glucose was used as a tracer to calculate H{sub 2}O space of cells. To stop reaction, cells were quenched in methanol and extracted to give lipid, free-choline, and phosphorylated choline fractions. With 5 uM external choline, cellular accumulation in all three fractions was linear for 30 min and free choline reached a 9-fold accumulation (inside/outside) ratio. With 0.1 mM external choline, the accumulation ratio reached a constant value of approx. 3 after 2 min incubation. With 1.5 min incubation, cell [choline] reached a plateau at approx. 30 uM external choline with a Km for uptake of approx. 8 uM. Efflux from preloaded cells showed two cellular components with a rate constant for the slow component of 0.031/sec. Uptake was inhibited 52% by hemicholinium-3 (10{sup -4} M), 41% by N-ethylmaleimide (10{sup -5}M), 30-50% by mitochondrial inhibitors, 15% by ouabain (0.5 mM) and 85% by incubation at 4{sup 0}. Omitting

Na{sup +} had no effect on uptake. These results indicate that granular pneumocytes accumulate choline from the medium against a concentration gradient by an energy-dependent process indicating active transport of this substrate.

Na{sup +} dependent glycine transport decreased steadily during cleavage of mouse embryos and then increased dramatically upon formation of early blastocysts ({similar_to}80 h post coitus), while proline uptake increased several-fold upon fertilization of eggs and then decreased through the blastocyst stage. V/sub max/ and K/sub m/ values for Gly transport in unfertilized eggs, 8-cell embryos and blastocysts were 9.5, 4.0 and 20 fmol. (egg or embryo){sup -1} min{sup -1} and 93, 94 and 30 {mu}M, respectively. Gly transport in 2-cell embryos was Cl-dependent and sigmoidally related to the [Na{sup +}], whereas Cl{sup -}-dependent Gly uptake was linearly related to [Na{sup +}] in blastocysts. Uptake of 1.0 {mu}M [{sup 3}H]Gly in cleavage stages was inhibited by 10 mM sarcosine but not by Glu, Ser, or Lys and only weakly by MeAIB, BCO and pipecolate, whereas BCO, Ser, Lys, Pipecolate, Ala and Leu strongly inhibited transport in blastocysts; and Lys inhibition was unequivocally competitive (K/sub i/ {similar_to}70 {mu}M). Na{sup +}-dependent uptake of 0.9 {mu}M L-[{sup 3}H]Pro was inhibited strongly by only pipecolate in unfertilized eggs, but MeAIB and BCO were also strong inhibitors in zygotes. Fertilization was also accompanied by an increase in the V/sub max/ (0.9 vs 6.7 fmol. cell{sup -1} min{sup -1}) and K/sub m/ (66 vs 230 {mu}m) values for proline transport. This appears to be the first report of a change in amino acid transport upon fertilization of mammalian eggs, although transport of several amino acids increases dramatically in sea urchin zygotes.

Addition of 70 mM choline chloride to Brinster's medium (140 mM Na{sup +}) inhibited uptake of {similar_to}1 {mu}M [{sup 3}H]glycine, leucine, lysine and alanine in blastocysts by about 50% each during a five-minute incubation period at 37{sup 0}C, whereas 70 mM LiCl, sodium acetate and NaCl or 140 mM mannitol had no effect. They attribute the apparent linear relationship between Gly transport in blastocysts and the square of the [Na{sup +}], observed when choline was substituted for Na{sup +} in Brinster's medium, to concomitant, concentration-dependent enhancement and inhibition of transport by Na{sup +} and choline, respectively. As expected, Gly uptake and the [Na{sup +}] were linearly related up to 116 mM Na{sup +}, when Na{sup +} was replaced with Li{sup +}. The rates of Na{sup +}-independent Gly and Ala uptake were <5% and <2% of the total, respectively, and similar when either Li{sup +} or choline replaced Na{sup +}. Therefore, neither Li{sup +} nor choline appears to substitute for Na{sup +} in supporting Na{sup +}-dependent transport in blastocysts. Na{sup +}-independent Leu uptake was 20 times faster than Gly or Ala uptake and appeared to be inhibited by choline in blastocysts since it was about 37% slower when choline instead of Li{sup +} was substituted for Na{sup +}. In contrast to blastocysts, choline had no effect on amino acid transport in cleavage-stage mouse embryos. The unexpected sensitivity of transport to choline in blastocysts underscores the importance of testing the effects of this substance when it is used to replace Na{sup +} in new transport studies.

Leucine appears to be taken up by a different transport process than lysine in mouse eggs and cleavage-stage embryos. Uptake of 0.4 {mu}M L-[{sup 3}H]Leu was predominantly Na{sup +}-independent and inhibited strongly by 10 mM BCO but weakly or not at all by MeAIB, Glu, Ser, Lys, Gly, Pro or pipecolate. Lys transport was also Na{sup +}-independent but inhibited strongly only by Arg. These data suggest that transport systems L and y operate in eggs and embryos during cleavage. In blastocysts, Na{sup +}-dependent Leu transport was inhibited strongly by BCO, Ser, Lys and Gly, moderately by Pro and pipecolate, but not by MeAIB or Glu; so system B/sup o,+/ may mediate this process. In contrast, Na{sup +}-independent Leu uptake by blastocysts was inhibited strongly by Lys, Arg, Trp, Tyr, Phe, Met, His and homoArg, moderately by Thr, Val and Ile, and weakly or not at all by BCO, Glu, Ser, Gly, pipecolate, Pro, sarcosine, cycloleucine, {alpha}-AIB, MeAIB, M{sub 2}PA or {beta}ATC. Na{sup +}-independent transport of 0.4 {mu}M L-[{sup 3}H]Lys was inhibited strongly by Leu and Arg, moderately by Ala, and weakly or not at all by BCO, BCH, Gly, Glu, Pro, MeAIB or Ser. Kinetic

studies showed mutual, competitive inhibition of transport between Leu and Lys. These data suggest that Na{sup +}-independent transport sites in blastocysts interact preferentially with bulky zwitterionic and cationic amino acids whose carbon-chains do not branch at the {alpha} or {beta}positions, although these sites seem to accommodate branching at the {beta}position better than on the {alpha}-carbon.

ATP and adenosine (A) stimulate phosphatidylcholine (PC) secretion in type II cells. ATP stimulates approx. 5-fold while A stimulates only 2-fold. There is evidence that the effect of A is mediated by the A{sub 2} subtype of the P{sub 1} receptor and involves an increase in intracellular cAMP. The aim of this study was to determine if ATP and A stimulate PC secretion by different mechanisms. Cells isolated from the adult rat were incubated with {sup 3}H-choline for 20 h, transferred to fresh medium and incubated with the test compounds for 90 min when {sup 3}H-PC in the cells and medium was measured. At the optimal concentration (1 mM), ATP increased secretion by 4.5-fold from 0.90 +/- 0.04% of total {sup 3}H-PC in the medium to 4.08 +/- 0.39% (n=9; p < 0.001). The protein kinase C activator, 12-0-tetra-decanoyl-13-phorbol acetate, similarly increased PC secretion 3.6-fold from 0.97 +/- 0.06 to 3.47 +/- 0.53% (n=4; P < 0.02). The effect of ATP (0.1 mM) was reduced over 50% by prior incubation with the P{sub 2} desensitizing agent {alpha}, {beta}methylene-ATP (0.1 mM) but only 20% by the P{sub 1} antagonist 8-phenyltheophylline which reduced the effect of A by 50%. Terbutaline doubled the rate of PC secretion and this effect was additive to that of ATP but not to that of A. In contrast to A, which increased the level of intracellular cAMP 12-fold, ATP only produced a 3-fold increase in cAMP from 0.23 +/- 0.05 to 0.72 +/- 0.13 pmol/10{sup 6} cells (n=3). These data suggest that A and ATP stimulate PC secretion by different mechanisms.

The frequency content of signals emanated from small earthquakes that occurred in the aftershock area of the Kalapana, Hawaii mainshock of November 1975 in the period 1962-1981 were analyzed by spectral methods. Two of the source parameters obtained, namely the stress-drop and the apparent stress, were then employed as measures of the high- to low-frequency ratio of the signals, and these ratios were correlated with the location of the generating events. Events occurring in anomalous zones, previously proposed to be asperities, were shown to have higher frequency content than those in neighboring volumes. By analyzing events that took place before the occurrence of the mainshock and comparing them with those which took place after it, it was concluded that the average stress release per event is not a measurable function of ambient stress in the volume studied. The partitioning of stress involved in the generation of south flank events was studied. Events occurring before the mainshock had the same amount of partial stress drop on average as those occurring after it. No change was detected as a function of space. Results reflect that properties such as the strength of the rocks remain unaltered and, therefore, asperities remain asperities after the occurrence of a large event.

This study examines the changing terms and organizational forms of technology transfer by MNCs within the pharmaceutical industry in Latin American countries. Host government regulation was able to attract entries by MNCs and reduce their level of direct contractual costs for transfers, but also encouraged more unregulated internal transmission within MNC organizations. The internalization of imperfect markets for intangible marketing and technological advantages avoided stricter host regulations, but simultaneously increased policy conflicts with governments. The process of technology transfer by MNCs became more politicized and negotiable in the industry during the 1970s. The costs of transfers were determined more by organizational and bargaining power factors than by economic processes. Government regulation reduced royalty payments and restrictive business practices in technology licensing agreements, but host nations were still dependent on imports and new products from MNCs. The bargaining position of host governments improved as competition among oligopolistic MNCs increased and pharmaceutical technology matured. More

investments in local raw material manufacturing were stimulated, and internal transfer pricing manipulation was reduced by government regulations.

In the standard Leontief input-output model, a single dominant technology is assumed in the production of a particular commodity. However, in the real world, quite similar commodities are produced by firms with vastly different technologies. In addressing this limitation, the Probabilistic Production Path model (PPP) is used to investigate both the method of production and identity of the producer. An important feature of the PPP model is the consideration of the effects that heterogeneous technologies and dissimilar trade patterns have on the properties of the distribution of input-output multipliers. The derivation of the distribution of output multipliers is generalized for discrete probabilities based on market shares. Due to the complexity of the generalized solution, a simulation model is used to approximate the multiplier distribution. Results of the model show that the distributional properties of the multipliers are unpredictable, with the majority of the distributions being multimodal. Typically, the mean of the multipliers lies in a trough between two modes. Multimodal multiplier distributions were found to have a tighter symmetric interval than the corresponding standard normal confidence interval. Therefore, the use of the normal confidence interval appears to be sufficient, though overstated, for the construction of confidence intervals in the PPP model.

In order to demonstrate ability to meet air quality standards set by the Federal Government, specifically, by the Environmental Protection Agency (E.P.A.), Colorado implemented an Automobile Inspection and Readjustment (A.I.R.) program. As the A.I.R. program matured it became evident, through continued monitoring, covert investigations, and preliminary studies, that major discrepancies existed in the program's data and that Colorado would not be able to show sufficient reductions in vehicle emissions using the present program standards. The focus of this study was to explore those discrepancies and pinpoint where they may be occurring. To do so, the researcher collected data from a roadside pullover survey and compared this data with that reported by the A.I.R. mechanics. The following research questions were asked: (1) What is the actual effect of the A.I.R. program on emissions? (2) What is the reported effect of the A.I.R. program on CO emissions? (3) Are cars being pre-tuned to reduce CO emissions prior to the reported initial readings? (4) Are cars being readjusted after the A.I.R. inspection? Major results revealed that apparently no actual CO reductions were realized as a consequence of the A.I.R. program. Evidence showed that vehicles were not pre-tuned to reduce emissions prior to the reported initial reading, and that vehicles were not readjusted after the A.I.R. inspection.

Standard pulse-echo techniques have been applied to measure ultrasonic attenuation in single crystals of PdD/sub .67/H/sub .02/, of PdH/sub .67/, and several samples of PdD/sub x/ with x ranging 0.64 to 0.72, over the temperature range of 77 to 300 K. The longitudinal and two independent transverse waves were propagated along the [110] crystal axis. Attenuation peaks were observed for all three acoustical modes. In addition to a Zener-type relaxation peak, a relaxation peak that exhibits unusual features is observed in the temperature range of 110 to 140 K, but only for the longitudinal model. This peak is observed in all deuteride samples including the mixed isotope sample, but not in the hydride samples. The relaxation strength of this peak increases with increasing temperature. The peak is narrower than a Zener-type relaxation peak. A good description of the results is given in terms of a two-level system (TLS) with a single relaxation time. The energy gap between the two levels is remarkably close to the energy of the longitudinal optic phonon in PdDx. In contrast to earlier suggestions, the results from the analysis of {delta} and {delta}', and of the gradients of the H(D)-vacancy ordering energies of PdD/sub .67/ and PdH/sub .67/ do not show a strong isotope dependence.

Collection of particles by fibrous filters in the presence of an external electric field was studied. A numerical method for solving the particle trajectories was developed using the full Navier-Stoke equations. In this study,

the influence of the externally applied electric field on dendrite formation was also considered. A staggered array of cylinders was used as a model of a fibrous filter. A typical cell within the filter is defined. Particles enter the cell at random locations through the upstream face. The trajectory of each particle is computed numerically. The location of the particle within the cell is continuously checked. If the particle is deposited, either on a fiber or on an already deposited particle, its final location is recorded. Using this model, filtration efficiencies of fibrous filters with packing densities ranging from 0.0194 to 0.0982 were calculated. Particles in the 0.5 to 1.25 micron range were used and filtration velocities were varied between 1.0 and 100.0 cm/s.

Incident 0.5 to 2.5 MeV charged particle beams were used to ionize the inner shells of selected targets and study their subsequent emission of characteristic x-rays. {sup 9}Be{sup +} ions were used to examine K-shell x-ray production from thin F, Na, Al, Si, P, Cl, and K targets, L-shell x-ray production from thin Cu, Zn, Ge, Br, Zr, and Ag targets, and M-shell x-ray production from thin Pr, Nd, Eu, Dy, Ho, Hf, W, Au, Pb, and Bi targets. L-shell x-ray production cross sections were also measured for {sup 27}{sub 13}Al{sup +} ions incident upon Ni, Cu, Zn, As, Zr, and Pd targets. M-shell x-ray production cross sections were measured for {sup 27}{sub 13}Al{sup +} and {sup 40}{sub 18}Ar{sup +} ions incident upon Pr, Nd, Gd, Dy, Lu, Hf, Au, Pb, Bi, and U targets. The measurements were performed using the 2.5 MV Van de Graaff accelerator at North Texas State University. The experimental results are compared to the predictions of both the first Born and ECPSSR theories. The measurements presented show that the first Born theories overestimate the measured results rather significantly for all experiments using the {sup 9}Be beams to examine the inner shell x-rays, while the ECPSSR predictions fit the measured data much better. For incident {sup 27}Al and {sup 40}Ar ions, the measured results are not predicted by the theories.

Several extensions of Esscher's large deviation method, especially the problem of determining the reliability of interconnected systems where the two system loads are correlated, are investigated. Several alternative algorithms obtained from the simple extensions using saddlepoint approximation turn out to be as effective as the original large deviation method in evaluating system reliability and production costs. With the use of the first-order of the bivariate tetrachoric series expansions for the bivariate normal distribution, the large deviation method is extended to approximate the loss-of-load probability indexes for interconnected systems. Numerical results indicate the accuracy of the bivariate version of the large deviation technique in providing accurate estimates for the generation reliability of interconnected systems. Another topic investigated was development of the large-deviation method in production costing context where multiple-block dispatching is considered. In this situation, different blocks of a given unit are not statistically independent. Also examined was an enhancement to the computational performance of the large deviation method in the production costing framework. The large deviation approach to production costing is found to be quite effective when a mixture of normal approximation is used as well as for the multiple-block dispatching situation.

Vanadium pentoxide was added as a sintering aid to calcined PZT 96/4 to lower the sintering temperature of the PZT. No extra PbO was added to the PZT batch, and no provisions were made for a PbO environment during sintering. A Box-Behnken experimental design was employed with the following three factors: wt% V{sub 2}O{sub 5} added (0.3 to 0.5) sintering temperature (1000 to 1200{sup 0}C), and sintering time (2 to 8 hours). Analysis of the samples included: density, dilatometry, electron microscopy, differential thermal analysis, x-ray diffraction, hysteresis loop, and secondary ion mass spectrometry. Results from dilatometry, differential thermal analysis, and secondary ion mass spectrometry led to the following conclusions on how V{sub 2}O{sub 5} enhances the sintering of PZT 96/4: (1) a vanadium-bearing phase forms (perhaps a lead vanadate); this phase subsequently melts at approximately 800{sup 0}C; (2) melting of this vanadium-bearing phase results in more rapid sintering; sintered densities

greater than 95% theoretical are attainable at sintering temperatures as low as 1000{sup 0}C; (3) the vanadium-bearing compound segregates; vanadium does not diffuse completely and homogeneously into the PZT matrix even after sintering at 1200{sup 0}C for eight hours.

This work describes the behavior of assemblies of individual energy converting subunits. The linear phenomenological laws of nonequilibrium thermodynamics are used as constitutional equations that describe the relationship between the forces and flows of a subunit. These relationships along with the restrictions imposed because of the organization of the system are used to derive equations relating the overall flows and forces. Two types of systems are considered: where the total input flow is the sum of the individual input flows, and the output flow is either also the sum of the subunit flows or is the same as each subunit flow. Most of the effort was directed toward describing systems in which the subunits are not all phenomenologically identical and the fractions of subunit types vary. Systems containing two distinct types of subunit were studied. Several properties are investigated, including limiting operating states and the input flows needed to support these states. As an example, muscle contraction is considered as a system where the output flow is the same for each subunit. Unfortunately, because it is not yet possible to measure the number of active subunits in muscle, applications of the theory is limited to describing properties that do not depend on the number of subunits.

In previous studies, biological activity on granular activated carbon (GAC) beds has been found to account for long term, steady state removal of both naturally occurring organic compounds and synthetic organic chemicals (SOCs), the latter being noted in controlled laboratory experiments. The effects of both direct biodegradation of substrate from the solution and renewal of sorption sites (bioregeneration) by diffusion and biodegradation are important to describe in order to take maximum advantage of biological activity in design and operation of GAC beds. The proposed model is improved in the following ways: (1) unsteady state biofilm growth, decay and hydrodynamic shearing are included (diffusion with Monod biokinetics occur in the biofilm), (2) substrate fluxes to the biofilm from both the solution side and the adsorbent side are accounted for explicitly and (3) intraparticle surface diffusion coupled with non-linear sorption account for substrate adsorption and desorption (the latter occurs after the biofilm is established). The model is tested at substrate concentrations of 20 to 100 {mu}g/l, and the model's performance is more generally examined for the case of transients in feed concentration. The model was tested successfully with experimental data collected in-house for effluent substrate concentration and rate of bioregeneration. Less successful was verification using data from an independent source in the literature collected under higher feed concentration.

Detailed experiments confirm the narrowing of ac Stark-broadened 2 + 2 multiphoton ionization (MPI) spectra of nitric oxide (NO) at room-temperature thermal equilibrium in a cell at pressures on the order of one Torr. Experiments with a supersonic beam of NO at comparable pressures exhibit no such narrowing. Both results can be predicted by a collective model depending on whether the molecular phases are random or coherent. The spectral line shapes obtained with different focusing geometries are successfully reproduced, which indicate a strong dependence of asymmetric broadening upon temporal and spatial inhomogeneities of a laser intensity. Multiphoton ionization spectra of chlorine reveal that photodissociation produces prominent lines and is also responsible for third harmonic generation (THG), which in turn excites some spin-forbidden transitions by one-photon absorption. Change and complications of state symmetry assignment by polarization technique in the presence of photodissociation and THG are discussed. Qualitative differences of third harmonic interference effects in atomic and molecular systems are also discussed. Details of the mysterious pressure effects in rare gas atoms are discussed in terms of MPI spectra of argon.

This case study was an attempt to divulge the presence of environmental education (EE) in the intermediate-grade curriculum, along with the factors influencing it both positively and negatively. It was designed in response to Goal No. 7 of the New York State Regents Action Plan, which advocates EE in all subject areas and at all grade levels. The site of the study was a public school in Queens, New York, The participants included 7 teachers, the school librarian, 2 administrators, and 15 fourth, fifth, and sixth graders, as well as 3 educators from outside the school. This research was conducted between February and June, 1986. The data-collection techniques involved observations, in-depth interviews, and artifact reviews. The findings revealed that EE does exist both blatantly and subtly in the intermediate-grade curriculum; however, much more can be done. In science, exploration of plants, animals, energy, climate, air and water quality are replete with environmental ramifications. In social studies, consideration of the dependence of human cultural development on the natural environment is key. Environmental themes are employed to teach mathematical, reading, and language arts skills. Much music is developed around the imitation of the sounds of nature. Current events bring environmental issues to the foreground.

This study bridges the gap between narrow quantitative analyses and global scale qualitative analyses by developing and testing a regression model of labor productivity growth in four-digit Standard Industrial Classification (SIC) US manufacturing industries. It applies rigorous quantitative analysis, characteristic of the neoclassical approach, within a broad conceptual framework based on an interpretation of the post-war era as a time of structural change in World markets, and ideological transition in America. The analytic framework offers a coherent world view within which relationships believed to have influenced manufacturing productivity growth can be hypothesized as if industries operated in a regime of structural change and transition. Twenty-two explanatory variables are introduced, including traditional neoclassical production function variables, a wide range of variables intended to characterize industries best able to adapt to a climate of uncertain and changing economic conditions, and several additional variables that arise from a methodological variation for refining the productivity growth model. The final regression equation is able to explain 73% of the variation in labor productivity growth in a cross section of 99 four-digit SIC manufacturing industries for the period 1973 to 1979.

The crosshole and downhole seismic methods are widely used in engineering as a reliable means of in situ determination of the variation of elastic moduli with depth. The crosshole method is more expensive to conduct in the field than the downhole method, but it is also easier to analyze the seismic results. However, if a soft layer is sandwiched between hard layers, it is often difficult to identify the first arrival of the direct shear wave in crosshole records. To investigate this problem, theoretical seismograms were developed based upon ray theory. Interference from reflected and refracted (head) waves on the direct shear wave was studied. By comparing theoretical seismograms and real records, it was found that converted reflected waves are more critical than head waves in interfering with the first arrival of the direct shear wave. The lack of a sophisticated and mathematically rigorous analysis method of downhole data results in a less detailed shear wave velocity profile than determined by the crosshole method. This lack of detail prevents one from exploiting some of the advantages of the downhole method such as low cost, ease of operation, and use of a simple seismic source. A new method of analyzing downhole data is developed. The method is based on inverse theory and permits determination of detailed shear wave velocity profiles. The inversion method is shown to be clearly superior to conventional analysis methods.

Multistage interconnection networks are one of the very few cost-effective alternatives for connecting a large number of computers for parallel execution. Due to the high complexity of multicomputer systems, faults are bound to occur in such systems. Fault tolerance is crucial for retaining high availability of the systems and assuring their efficient operation. When fault tolerance is

incorporated into the system, faults do not force its complete shut-off and the system is able to continue its successful operation in their presence perhaps with some, graceful, degradation in its performance. This research explores fault tolerance in multistage interconnection networks-based multicomputer systems. Using a graph theoretic approach but relating to practical systems, it studies the impact of faults and systematically by means of a specially introduced methodical terminology, analyzes the inherent fault tolerance capabilities of such systems, mainly the systems based on non redundant multistage interconnection networks. Recovery schemes utilizing these capabilities, which enable the systems to operate successfully in the presence of faults, are proposed. These schemes involve real-time fault detection and location and on-line recovery via reconfiguration.

This study tests for evidence of a dividend tax aversion effect impounded in the price of public utility stock. Previous tests for dividend tax aversion rely upon empirical tests of the after tax capital asset pricing model. These previous tests employ regression procedures in which the stock return is the dependent variable, and the market return and a dividend yield variable are the independent variables. The previous studies interpret a positive coefficient of the yield variable as indicating dividend tax aversion. This study argues that these procedures cannot separate dividend tax aversion from other dividend effects. The Economic Recovery Tax Act of 1981 modified the tax treatment of dividend reinvestment plans of public utilities. Under the provisions of the law, investors could avoid the ordinary income tax on dividends by participating in qualified dividend reinvestment plans. Any dividend tax aversion that would be present in the prices of public utility stock would have been removed by the law. The study examines the prices and returns of public utility stock during the change in the tax rules. It finds that there was a significant price penalty associated with the taxes on dividends and that the price penalty was removed by the dividend reinvestment provisions of the Economic Recovery Tax Act of 1981. The study concludes that there is a significant tax related effect impounded in the prices of dividend paying securities.

A measure of intertemporal consumer surplus is used to formulate the objective function in a model of welfare maximizing public utility which serves a market with a dynamic demand structure. An important advantage of the model structure utilized is that it specifies dynamic demand using the same distributed lag functional form as is often used in empirical work. The model is formulated as an autonomous, infinite horizon optimal control problem. An analysis of the first order necessary conditions indicates that, under steady-state conditions, a policy of marginal cost pricing should be followed. The basic model is modified by adding a breakeven constraint to produce a dynamic version of the well known Ramsey pricing rule. A comparison of the dynamic rule with that derived for the static case indicates that significant errors can result if the latter is applied in cases where demand exhibits a dynamic structure. Finally, some implications of the dynamic demand phenomenon for the regulation of public utilities are considered. It is shown that, if two utilities serve markets with equal short-run price elasticities, but one market has a dynamic demand structure and the other does not, then the difference between profit maximizing prices and Ramsey-optimal prices will be smaller in the dynamic market.

Neoclassical duality results allow the modeling of steam electricity production technology with a Diewert-flexible Translog cost specification, appropriately constrained for the regularity conditions. The model was fitted to 1981 cross-sectional sample of regulated investor-owned electric utilities operating in the East North Central US. The neoclassical cost function and factor cost share equations are jointly estimated for efficiency. Characteristics of the technology (including firm-level scale economies) are then obtained from maximum likelihood coefficients of Zellner's joint GLS Seemingly Unrelated Regressions. The estimated minimum cost function can be viewed as an m-dimensional response surface described by statically significant arguments, is well behaved, and corresponds to that of a nice neoclassical technology. Overall study findings provide specific confirmation for possible significant regional differences in

the production structure of steam electricity generation within the US. The study furnishes tentative evidence that a broad national industrial policy for this industry will be misplaced unless proper adjustments are made for regional asymmetries in production cost structures.

The purpose of this dissertation is to examine the relationships between the strategic nuclear force levels of the US, Soviet Union, and other nuclear powers in order to provide a better understanding of the process by which arms levels are determined. By applying advanced econometric techniques to arms level data, the historical behavior of the nations may be dissected. The findings thus obtained may be compared to previous empirical findings and to the predictions of the theoretical literature on arms races. The major findings of this work are as follows. First, that there is interaction between the various components of the nuclear arsenals of the US and Soviet Union. Previous studies that examined only strategic aggregates missed these interactions. Second, the SALT I treaty did not significantly alter the behavior of these nations. Third, the nuclear-armed NATO nations (Great Britain and France) and possibly the People's Republic of China are important in determining the overall strategic posture of the US and USSR. Finally, process through which the arms levels of the nations studies are determined yield stationary time-series. That is, there is not an arms race with weapons levels spiraling upward indefinitely but a process that is stable in the short run.

A major determinant of energy conservation is the physical form of an urban area. Different forms and structures offer inherently different possibilities for conserving energy. This is particularly evident in the transportation sector where the conjunction of population density, employment opportunity, transportation system, and service characteristics largely determine the levels of savings that can be attained. Thus, the problem confronting policy makers, interested in saving energy, might be seen as one of appropriately guiding development in the direction of various urban forms, or morphological states, offering further opportunities for energy savings. This problem is complicated by the necessity of sustaining acceptable levels of social benefits. Furthermore, political pressure often constrains policy-making within a relatively short time-frame, yielding immediate gains that do not maximize longer term benefits. Data are developed, using a sequence of computer models, describing salient formal and performance characteristics of a number of theoretical urban forms, or morphological structures. These data are further related within an overall structure of transportation supply and demand (and the identified domains within the framework) within which maximum energy benefits are to be found. Estimations are then made of costs associated with moving from one morphological state to another.

The purpose of this study was to analyze selected cognitive theories in the areas of artificial intelligence (A.I.) and psychology to determine the role of emotions in the cognitive or intellectual processes. Understanding the relationship of emotions to processes of intelligence has implications for constructing theories of aesthetic response and A.I. systems in art. Psychological theories were examined that demonstrated the changing nature of the research in emotion related to cognition. The basic techniques in A.I. were reviewed and the A.I. research was analyzed to determine the process of cognition and the role of emotion. The A.I. research emphasized the digital, quantifiable character of the computer and associated cognitive models and programs. In conclusion, the cognitive-emotive research in psychology and the cognitive research in A.I. emphasized quantification methods over analog and qualitative characteristics required for a holistic explanation of cognition. Further A.I. research needs to examine the qualitative aspects of values, attitudes, and beliefs on influencing the creative thinking processes. Inclusion of research related to qualitative problem solving in art provides a more comprehensive base of study for examining the area of intelligence in computers.

This thesis is devoted to a study of the impact of these changes in the international oil market on the different sectors of the Saudi economy. A macro

economic model of the economy was developed and econometrically estimated, using annual data from 1962-1983. The model consists of 31 relations, 16 behavioral equations, and 15 identities. The predictive ability of the model was established through historical simulation and a one-period out of sample forecast. In general, this model is superior to existing models of the Saudi economy because it is more disaggregated and also because it is structure to allow the simulation of alternative economic futures. Ex-ante simulations were performed for the period 1985-1990. These simulations were divided into two stages: the first covering the period 1985-1986 for which actual data for oil prices, production, exports, and government revenues were available; the second covered the years 1987-1990, in which the future of the Saudi economy was examined under three different world oil price scenarios. Analysis of the results of these scenarios revealed that the Saudi economy is sensitive to fluctuation in world oil prices and also very vulnerable. Even under the optimistic price scenario, government oil revenues will fall considerably short of the estimated 200 billion Saudi riyals suggested by the Fourth Development Plan, 1985-1990.

Integral process models were developed to predict particle melting in both DC and RF plasmas. Specifically, a numerical model has been developed to predict the temperature history of particles injected in a low pressure DC plasma jet. The temperature and velocity fields of the plasma jet are predicted as a free jet by solving the parabolized Navier-Stokes equations using a spatial marching scheme. Correction factors were introduced to take into account non continuum effects encountered in the low pressure environment. The plasma jet profiles as well as the particle/plasma interactions under different jet pressure ratios (from underexpanded to overexpanded) were investigated. The flow and temperature fields in the RF plasma torch are calculated using the axisymmetric Navier-Stokes equations based on the primitive variables, along with pseudo two-dimensional electromagnetic field equations. Particle trajectories and heat transfer characteristics in both DC and RF plasmas are calculated using predicted plasma jet profiles. Particle melting efficiencies in both DC and RF plasmas are evaluated and compared using model alloy systems. Based on the theoretical considerations, an alternative route of plasma spraying process (hybrid plasma spraying process) is proposed. An evaluation of particle melting in hybrid plasma jets had indicated that further improvement in deposit properties could be made.

Planar non-overlapping shape analysis is an important computer vision problem with applications in industrial parts inspection, character recognition, target identification, biological cell analysis etc. Subtopics emphasized in this research include shape representation, measurement, and classification. A unified approach composed of contour based algorithms for solving problems of each types is developed, where contour techniques are potentially efficient because they involve relatively small quantities of data. Assuming that the input images have been properly binarized, contours defining distinct shapes can be extracted by following cracks (i.e., borders between black and white pixels). Shapes can then be aligned by matching their m-point contours. It is shown that given start point K on one contour, optimal scale, rotation and Euclidean distance, d(k), are non-linear functions of sample cross covariances at lag k between the x and y contour coordinate sequences. Contour models are data compressed shape representations, where the model parameters are contour transforms. An intriguing contour based shape recognition scheme, with classification cost virtually independent of the number of prototypes, is also presented. It utilizes complete shape information, is scale-translation-rotation invariant, and feasibly realizable.

Rehydration of the active sites of carbon and carbon black formed after vacuum heat treatment of the samples at high temperatures is reflected in the heats of their immersion in benzene and water: for carbon, the heat of immersion in benzene does not change, but the heat of immersion in water increases markedly, while the heat of immersion of carbon black in benzene decreases markedly and the heat of immersion in water almost does not change. All four basic stages of

adsorption of water vapors on active carbon: (1) the formation of water clusters, (2) formation of a random monolayer, (3) volume filling of micropores, and (4) saturation with capillary condensation phenomena in the mesopores, are reflected in the curve of the dependence of the heats of immersion of carbon in benzene on the relative vapor pressure of the preadsorbed water. Based on the study of the heats of immersion of AC-47 active carbon in benzene as a function of the amount of preadsorbed water, the reality of the existence of a statistical monolayer or similarity of the monolayer of water in the micropores of nongraphitized active carbon not made chemically hydrophobic, formed in the narrow region of relative water vapor pressures from 0.45 to 0.6, was demonstrated.

Based on the theory of volume filling of micropores, a generalized Dubinin equation for the adsorption of vapors by an adsorbent with an inhomogeneous microporous structure and an arbitrary shape of the micropores was obtained. The Dubinin-Stoeckli equation for a slit model of micropores is a particular case. The isotherms of adsorption of benzene vapors on active carbon with a broad distribution of micropores and significant development of the volume and area of mesopores were studied in detail. The equations of the theory of volume filling of micropores permit describing the adsorption isotherms with totally satisfactory precision.

It is proposed to extend the method of constructing characteristic adsorption curves and of describing them using the TMVF equation to the region of supercritical temperatures for pure adsorbates. In constructing characteristic curves it is necessary to use standard states of the components in the two phases that are in equilibrium with each other. Using the adsorption of Xe, Kr, and CF{sub 3}Cl on NaX as examples, the methods of dining the corresponding standard states are considered.

Zeolite (Na,Li)ZK-5, which is a structural analog of zeolite ZK-5 previously obtained in the Na-aluminosilicate system with a predominant concentration of an organic base, was synthesized in the Na,Li-aluminosilicate system. With respect to the volume of the adsorption space accessible for molecules of H{sub 2}O, zeolite (Na,Li)ZK-5 is similar to zeolite ZK-5, but differs from it with respect to the molecular-sieve properties.

Based on silica gel containing a {gamma}-aminopropyl group and {alpha}-, {beta}, and {gamma}-aldehydes of the heterocyclic series, supports having graft aldimine groups and their stable complexes with palladium have been obtained. It has been established by IR spectroscopy that the hydroxyl coating of silica gel is almost completely replaced by functional groups of ligands combined with the surface through O atoms. The Pd atom is coordinated by the N atom of the aldimine group, the heteroatom of the pyridine ring, and in the case of furan by the {pi}-electrons of the ring. The catalytic activity and selectivity of Pd complexes in the isomerization and hydrogenation of allylbenzene is determined by the nature of the grafted heterocyclic ligand.

A diamagnetic oxygen complex of a cobalt porphyrinate, probably possessing a peroxide structure, was detected in aqueous solution. The coordination of epinephrine or DMFA causes a breakdown of this compound with the formation of a paramagnetic superoxide complex. The breakdown of the porphyrin macrocycle in the course of the oxidation of epinephrine occurs under the action of its oxidation products.

The catalyst prepared by attachment of Co(II) ions on granules of the graft copolymer of polyethylene with acrylic acid effectively catalyzes liquid-phase oxidation of cyclohexene, ensures chain propagation (in the initial stage of the reaction) due to activation of oxygen by Co(II) ions, and catalytic decomposition of hydroperoxide with emission of radicals into the volume. Chain breaking takes place both in bimolecular recombination of alkenyl peroxide radicals in the bulk and with the participation of cobalt ions on the surface of the catalyst (linear breaking). The reactions of complexing and decomposition of cyclohexenyl hydroperoxide with Co(II) and Co(III) acetylacetonates were

studied. The corresponding complexing constants, initiation constants, and order of the reactions were estimated. The structure of the heterogeneous catalyst was studied by IR spectroscopy.

The complex studied - penta(dimethylsulfoxido)vanadyl hexathiocyanatoplatinate (I) is an effective catalyst for the low-temperature oxidation of cyclohexene in alcoholic media, ensuring a high reaction rate up to a high degree of conversion. It has been established that there is a synergism between the component parts of the catalyst, the maximum rate of oxidation of cyclohexene being observed with V/Pt = 2. In the initial stages of the oxidation of cyclohexene in the presence of (I), the reaction rate is described by the kinetics of a chain growth-chain breaking process.

Oxidation of cyclohexenyl hydroperoxide by molecular oxygen in the presence of penta(dimethylsulfoxido)vanadyl hexathiocyanatoplatinate proceeds at a high rate at low temperatures with the formation of bifunctional, oxygen-containing products. The main route of the reaction is the molecular oxidation of the hydroperoxide with ring opening in a complex [Cat/sub m/...HOOR/sub n/]; oxidation of cyclohexenyl hydroperoxide to a dihydroperoxide takes place simultaneously by a chain mechanism.

A comparative polarographic study of the phenylvinylidene compounds Cp(CO){sub 2}Mn=C=CHPh (I), Cp{sub 2}(CO){sub 4}Mn{sub 2}({mu}-C=CHPh) (II), and Cp(CO){sub 2}MnPt({mu}-C=CHPh)LL' (III-IX), where L and L' may be P(OR){sub 3} or CO, has shown that the coordination of the Mn=C bond to a second metal atom results in transposition of the electrophilic center from the {alpha}-C atom of the vinylidene group in I to the Mn atoms in II and the Pt atom in III-IX. A correlation between the potential for the electrochemical reduction of the complexes Cp(CO){sub 2}MnPt({mu}-C=CHPh)LL' and the energy of the {sigma}{yields} {sigma} transition of the metal-metal bond in their UV spectra has been established. The attachment of the donor substituents L and L' to the Pt atoms in compounds III-IX results in an increase in the strength of the Mn-Pt bond. The donor interaction between the Pt atom and the semibridging carbonyl group causes the opposite effect.

1H-1-Oxo-2,4,6,8-tetrakis(tert-butyl)phenoxazine undergoes ligand exchange reactions and behaves as a spin trap for metal-centered radicals, as a result of which stable paramagnetic complexes are formed with delocalization of the unpaired electron in the organic ligand. Paramagnetic complexes are also formed as the result of a reaction between potassium salt (IA) and triphenyl-tin and triphenyl-lead monochlorides.

It has already been shown that 2-amino-4,6-di(tert-butyl)phenol reacts with 3,5-di(tert-butyl)-o-benzoquinone to form 1H-1-oxo-2,4,6,8-tetrakis(tert-butyl)phenoxazine (I), which is readily reduced by alkali metals to the corresponding semiquinone anion-radical (II), and further to the diamagnetic dianion (IIA). They made use of this ability of (I) to undergo reduction to prepare anion-radical salts with different group II-IV metals in the form of their amalgams. In the EPR spectrum of the anion-radical complex (III) formed in the reduction of (I) by a thallium amalgam, the HFI constants of the unpaired electron with magnetic nuclei of the organic ligand are close to those of the K-salt (II), and a substantial HFI is observed with the /sup 203,205/Tl nuclei. This unequivocally proves that the complex has a semiquinone structure, since an HFI on the /sup 203,205/Tl nuclei of such an order of magnitude is characteristic of o-benzoquinone salts with a thallium cation.

When substituted o-benzoquinones (Q) are treated with tin amalgam, biradicals with bi- and tetravalent tin are formed. The biradicals can be reduced on the surface of an alkali metal to the corresponding anion radical. Two conformations with different shielding of the O atoms are observed spectrally, one of which undergoes a rapid intramolecular exchange and in the other this exchange is absent or proceeds slowly. It is proposed that the transition between these conformations occurs by rotation of the free-radical ligand about the Sn-O bond. In order to study further the structure of the conformers, they have synthesized

anion radicals with a Tl{sup +} cation, which by virtue of the magnetic properties of the cation (a large value for the nuclear magnetic moment of the {sup 203}Tl and {sup 205}Tl isotopes) provide more information when their EPR spectra are studied than anion radicals with cations of alkali metals. These anion-radical complexes are obtained.

Vinyl ethers were prepared by the well-known Favorskii-Shostakovskii method. The purity of the compounds was controlled by GLC and by the PMR and {sup 13}C NMR spectra. The proximity of sp{sup 7}-hybridized unshared pair of oxygen atoms result in a secondary, positive contribution in the constant of spin-spin interaction between neighboring carbon nuclei in the aromatic ring.

The authors generalize the results of their investigations of the donor capacity of Si-substituted aroxy- and (aroxymethyl)silanes with the general formula 4-X-C{sub 6}H{sub 4}OY (Y=CH{sub 2}SiEt{sub 3} (I), CH{sub 2}SiMeF{sub 2} (II), SiMe{sub 3} (III), SiMe{sub 2}C identical to CH (IV); X=MeO, Me, F, Cl, Br, I) when they form complexes with phenol and tetracyanoethylene (TCE). For comparison they studied the corresponding anisole derivatives 4-X-C{sub 6}H{sub 4}OMe (V). Complexes of Si-substituted aroxy- and (aroxymethyl)silanes with phenol and TCE were studied by the methods of IR and UV spectroscopy. The n- and {pi}-donor properties of compounds in which there are no p-{pi} interacting O and Si atoms decrease with increasing electron-acceptor properties of the substituent of the Si atom. The basicity of compounds with organosilicon substituents, bonded directly to the O atom, is determined by their summary electronic effect. The transmission coefficient of the O atom in the compounds studied is constant.

With the object of investigating the conformation with reference to the C/sub sp{sup 3}/-C/sub sp{sup 3}/ and C/sub aryl/-C/sub sp{sup 3}/ bonds, this work considered, with the aid of the complex application of the methods of dipole moments (DMs), the Kerr effect, and atom-atom potential functions, the stereochemistry of the title compounds. In the investigated 1,2-diaryl-substituted ethanes, the content of the trans and gauche conformers relative to the C-C bond is practically identical; the transform shows some predominance. In these compounds, the aromatic rings are orientated in parallel and are turned by an average of 120 +/- 10{sup 0} relative to the central C-C bond.

The authors carried out a conformational analysis of {alpha},{beta}dichloroethylbenzene, {alpha},{beta}dibromoethylbenzene, and their p-chloro derivatives with the general formula XC{sub 6}H{sub 4}CHHalCH{sub 2}Hal, where X = H, Hal = Cl (I); X = Hal = Cl (II); X = H, Hal = Br (III); X = Cl, Hal = Br (IV), dissolved in CCl{sub 4}. It has been shown by means of measurements of the dipole moments and of the Kerr and Cotton-Mouton effects that {alpha},{beta}dihaloethylbenzenes exist in CCl{sub 4} solutions in the form of equilibrium mixtures of two conformers with predominance of the less polar rotamers, in which the plane of the aromatic ring eclipses the C-H bond. Graphical methods for the conformational analysis of spin-spin coupling constants on the basis of J/sub i//sup HH/-J/sub j/ data and of the electric and magnetic birefringence constants (/sub m/K-/sub m/C) have been proposed.

To elucidate the priority of the orbital interactions, they investigated the steric structure and {sup 35}Cl NQR spectra of 1-chlorovinyl alkyl ethers CH{sub 2}=CCl-O-R with R=Me(I), Et(II), i-Pr (III). 1-Chlorovinyl alkyl ethers exist predominantly in the s-cis conformation. In 1-chlorovinyl alkyl ethers there is no specific eta-{sigma}interaction of the unshared electron pair of the oxygen atom and the antibonding orbital of the C-Cl bond.

Calculations using the MNDO method have been carried out for the intermediate and end products of the interaction between the acetylene and vinylidene molecules with molecules of LiOH and LiSH, and possible pathways for these reactions have been suggested. The optimal structures and the energies of formation of thermodynamically stable anions formed by the interaction of {sup -}SH and {sup -}OH with the molecules C{sub 2}H{sub 2} and H{sub 2}CC have been obtained, and it has been demonstrated that Li{sup +} contributes to the

nucleophilic attachment of the {sup -}OH and {sup -}SH anions to the triple bond to the same degree that the nucleophile contributes to the attachment of the electrophile Li{sup +}.

Cyclic and acyclic aldonitrones (AN) are oxidized by a variety of reagents to hydroxamic acids and their derivatives, or more extensively with cleavage of the C-N bond. For example, Pb(OAc){sub 4} and MnO{sub 2} in benzene oxidize 1-pyrroline 1-oxides to 1-acetoxy-2-pyrrolidones and 1-hydroxy-2-pyrrolidones, respectively, and oxidation with aqueous solutions of NaIO{sub 4}, KMnO{sub 4}, or NaOBr give the further oxidation products 1-hydroxy-2-pyrrolidones. On the other hand, cyclic AN give spin adducts with short-lived free radicals, and are used extensively as spin traps. The spin trap of the cyclic AN type most commonly used is 5,5-dimethyl-1-pyrroline 1-oxide (DMPO). Short-lived free radicals are frequently generated by redox reactions, commonly using Pb(OAc){sub 4} as the oxidant. The resulting spin adducts are converted by oxidants to substituted nitrones, but this reaction is complicated by the oxidation of the AN to hydroxamic acids or their derivatives. The aim of this investigation was to examine the behavior of imidazoline AN in comparison with DMPO in the presence of oxidants (Pb(OAc){sub 4}, PbO{sub 2}, and MnO{sub 2}) in benzene and methanol.

At {similar_to}20{sup 0}C, nitrile complexes of palladium(II) (0.1 equivalent per 1 equivalent of the substrate) easily isomerize 3,5-dialkyl- and 3,4,5-trialkyl-1,5-hexadien-3-ols to the corresponding {delta} epsilon-unsaturated ketones; low-temperature catalytic isomerization is the optimal variant of the hydroxy-Cope rearrangement for compounds of such a structural type. The absence of alkyl substituents at the C{sup 3} and C{sup 2} or C{sup 3} and C{sup 5} atoms in the 1,5-hexadien-3-ol molecule or the introduction of an alkyl group at the C{sup 1} atom makes the catalytic hydroxy-Cope rearrangement impossible or of low efficiency.

Reaction of vinylhalides (vinylbromide, 1-chloro-1-cyclopropylethylenes) with CH{sub 2}N{sub 2} in the presence of (PhO){sub 3}P x CuCl leads to formation of the corresponding halocyclopropanes with 13-15% yields, while reaction of CH{sub 2}N{sub 2} with alkylbromide under the same conditions gives the product of formal methylene introduction, 4-bromobut-1-ene (yield 58%), with insignificant formation ({similar_to}1%) of bromomethylcyclopropane.

The basic principles governing the cyclocodimerization of norbornene with allyl compounds have been elucidated for their reaction in the presence of a three-component catalyst system, Ni(acac){sub 2}-P(OR){sub 3}-AlR'{sub 3} (or MgR"{sub 2}); a highly selective method has also been developed for the introduction of a methylenecyclobutane fragment to a norbornene hydrocarbon derivative. A new Ni complex has been prepared; it appears to be the catalyst which is active for the cyclocodimerization of norbornene with allylic compounds.

The catalytic system of PdCl{sub 2}-CuCl permits the selective oxidation by oxygen in the THF solution of mono-, bi-, and tricyclic olefins, as well as 1,4E,9-decatriene, to high yields of carbonyl compounds. The Z double bond in the cyclic olefins possesses significantly less activity than the E-isomer in the oxidation by oxygen. The PdCl{sub 2}-CuCl system in combination with H{sub 2}O{sub 2}, NiO{sub 2}, KMnO{sub 4}, NaOCl, or the oxides of silver and manganese can be utilized as an effective reagent for the selective oxidation of linear polyenes to carbonyl compounds.

The cyclocooligomerization of allyl acetate with norbornadiene and its derivatives to compounds which are not readily accessible in the series tricyclo[4.2.1.0/sup 2,5/]nonane, tetracyclo[4.3.0.0/sup 2,3/.0/sup 2,4/]nonane and tetracyclo[4.4.1.0/sup 2,5/.7/sup 7,10/]undecane has been achieved with yields of 60-95%, involving the participation of low-valency nickel complexes.

The effect of catalysts of the Ziegler type: Ni complexes combined with organo-aluminum compounds (OAC), was studied for the first time in the reaction of cyclodimerization of 3,3-dimethylcyclopropene (DMCP): the role of the individual

components of these systems in this reaction was studied and it was shown that catalytic quantities of OAC activate the Ni complexes. Above a certain threshold concentration (in the conditions studied, > 0.05 g-atom Al/liter), OAC independently catalyze the reaction, apparently according to an ionic mechanism. The major role of the solvent in transformations of DMCP on the catalysts studied was revealed: highly selective cyclodimerization in ether (up to 93-95%) and fast polymerization with opening of the three-member ring in benzene. The results obtained are in agreement with the finding of dissociation of OAC in ether solutions with the formation of ion pairs.

A new series of cyclic compounds of four coordinate boron- the dialkylboryl-[(1,2,4-triazol-5-yl)amidinates] (IX)- has been synthesized from 5-amino-1,2,4-triazole, aromatic nitriles, and trialkylboranes. In the crystalline, dimeric dialkylboryl derivatives of 5-amino-1,2,4-triazole the Alk{sub 2}B groups are bonded to the ring N atoms. The crystalline and molecular structure of dipropylboryl[(1,2,4-triazol-5-yl)benzamidinate] (IXa) have been determined by X-ray crystallography.

Syntheses are reported for previously unknown hetero- and homometallic polynuclear thio complexes, (n-Bu{sub 4}N){sub 2} (Mo{sub 6}S{sub 20}), (n-Bu{sub 4}N){sub 2})Re{sub 2}Mo{sub 4}S{sub 16}), and K{sub 4} (Mo{sub 6}S{sub 16}).

Spiroorthoesters (SOE) are used for the preparation of nonshrinking polymers. The classical means for their preparation involves the reaction of {gamma}-butyrolactone (BL) with epoxides in the presence of Lewis acids with the formation of an intermediate complex of BL with the catalyst. They elucidate the reasons for the low yield of SOE in the reactions of BL with epichlorohydrin and the diglycidyl ether of 3-hydroxyphenol in the presence of Lewis acids. It is found that the yield of spiroorthoesters in the reaction of {gamma}-butyrolactone with epichlorohydrin depends significantly on the type of catalyst employed. An increase in the spiroorthoester yield requires the formation of nonequilibrium complexes between the catalyst and lactone. This excludes the polymerization of the epoxy compounds. On the other hand, the equilibrium between the complexes of the catalyst with the lactone and spiroorthoester should not be completely shifted toward the latter since this would lead to inhibition of the reaction.

In a continuation of a study of the rotational isomerism of 1-vinylpyrazoles, they studied the direct {sup 13}C-{sup 1}H coupling constants in the vinyl group of 1-vinylpyrazole, 1-vinyl-4-bromopyrazole, 1-vinyl-3-methylpyrazole, 1-vinyl-5-methylpyrazole, 1-vinyl-3,5-dimethylpyrazole, and 1-vinyl-4-nitro-3,5-dimethylpyrazole. The {sup 13}C-{sup 1}H direct coupling constants in the vinyl group of 1-vinylpyrazoles are stereo-specific and vary with change in the conformer ratio.

In their previous work, they showed that the homolytic reaction of 1-allylsilatrane with polyhaloalkanes gives 1-halosilatranes. In the present work, they discovered the addition of polyhaloalkanes to 1-vinylsilatranes both upon photochemical initiation and in the presence of peroxides. The ease of this reaction, its regiospecificity and high product yields permit them to recommend it as a preparative method for the synthesis of 1-polyhaloalkylsilatranes.

An induction period, post effect and shift in the telomer homolog distribution toward T{sub 1} were observed upon the use of Mn{sub 2}(CO){sub 10} as the initiator of the telomerization of 1-hexene with diethyl phosphite.

Macroporous and gel sulfo cation-exchange resins are active catalysts for the condensation of styrene with formaldehyde. The product, 4-phenyl-1,3-dioxane was obtained in up to 97% yield. The activity of macroporous sulfo cation-exchange resins increases with decreasing particle diameter but in the case of the gel samples, granule size has only a slight effect on the reaction rate. The enhanced activity of sulfo cation-exchange resins is presumably a result of the

high value of the acidity function H{sub 0} of the sulfonic acid groups of the cation-exchange resin.

Esters of substituted propane-1,1,3,3-tetracarboxylic acids cyclize to given high yields of esters of substituted cyclopropane-1,1,2,2-tetracarboxylic acids upon electrochemical oxidation in methanol in the presence of sodium iodide as an electron transfer catalyst.

They have detected the formation of Bi(II) and Bi(IV) in concentrated hydrochloric acid solutions and determined certain of their physicochemical properties using low-temperature radiolysis with optical recording, EPR spectroscopy, and pulse radiolysis. The formation of bismuth (II) and bismuth (IV) under the action of ionizing radiation on hydrochloric acid solutions of bismuth (III) has been shown by low-temperature and pulse radiolysis. The kinetics of bismuth (IV) disappearance at 300{sup 0}K have a complex nature and would seem to be caused both by the disproportionation of bismuth (IV) and the reaction of bismuth (IV) with bismuth (II), which leads to bismuth (III). The properties of bismuth (IV), which is formed from the reaction of Cl{sub 2}{sup -} with bismuth (III) agree with previously established relationships on the variation in optical transition energies and the unpaired electron density at the s atomic orbital of the ion for the series of isoelectronic ions mercury (I), thallium (II), lead (III), and bismuth (IV) in the {sup 2}S/sub 1/2/ state.

This work is devoted to a study of the dehydration of desmine by IR and NMR spectroscopy (wide line) using adsorption-desorption techniques, as well as DTA and x-ray photography. A new mechanism is proposed for the dehydration of desmine, according to which dissociation of some of the water molecules coordinated with the calcium cations occurs to form hydroxyls after a certain stage. It has been established that the processes of hydroxyl formation and dehydroxylation are the reasons for the irreversible deformation and the subsequent amorphization of desmine.

Vanadocene, generated by the amalgam reduction of Cp{sub 2}VCl{sub 2} (Cp = eta{sup 5}-C{sub 5}H{sub 5}) in a medium of aprotic solvents (DMFA, THF, dimethylacetamide, DMSO, etc.), containing phenol as a proton donor, effectively catalyzes the reduction of CO by sodium amalgam at {similar_to}20{sup 0}C and 1 atm with the formation of C{sub 1}-C{sub 4} hydrocarbons. In this work they studied the catalytic activity of other complexes of metals of subgroups IVB-VIB (M = Ti, Nb, Mo, W) in the amalgam reduction of CO in THF and DMFA medium. Differences in the catalytic activity of metallocene dichlorides of subgroups IVB-VIB in the amalgam reduction of carbon monoxide are due to thermodynamic factors determining the impossibility of amalgam reduction of the catalyst-substrate complex (subgroup IV) and differences in the stability of the corresponding metallocene (subgroups VB and VIB). Amalgam reduction of carbon monoxide, bound in a complex with metallocene, occurs under conditions of transfer of the first electron against the potential gradient.

The authors investigated the catalytic activity of some palladium clusters in the oxidation of models of the natural coenzyme of ubiquinol Q{sub 10}H{sub 2} by oxygen. They used as such models unsubstituted hydroquinone QH{sub 2} and synthetic ubiquinol Q{sub 9}H{sub 2} (the lateral hydrocarbon chain contains nine C{sub 5} structural units). To some degree, all the studied compounds catalyze the oxidation of hydroquinone. However, their activity depends significantly on the number of Pd atoms in the cluster. The highest catalytic activity was exhibited by a cluster of composition [Pd{sub 10} (Dipy){sub 4}(O{sub 2}){sub 3}]-(OAc){sub 2}. According to data of volumetry and iodometric titration, in H{sub 2}O at 20{sup 0}C and 1 atm of O{sub 2}, the absorption of 0.5 mole of O{sub 2} is accompanied by the formation of 1 mole of quinone. The results of iodometric titration in the presence of catalase and also the absence of a characteristic reaction with benzidine suggest that H{sub 2}O is not formed as the final product in the reaction.

The properties of high-silicon pentasils and mordenites of varying composition were compared in transformations of propylene and isobutylene and it was shown

that mordenites are {similar_to}10 times less active in the oligomerization reaction; they are also less active in the reactions of aromatization and redistribution of hydrogen and are deactivated during operation. Dealumination slightly increases the activity and stability of mordenites. The activity of pentasils and mordenites in oligomerization of olefins virtually does not change with an increase in the SiO{sub 2}/Al{sub 2}O{sub 3} ratio from {similar_to}30 to 280-300, while the aromatization reaction is more sensitive to a change in the concentration of Al in the backbone of the zeolites with SiO{sub 2}/Al{sub 2}O{sub 3} {approx}300, the yield of aromatic hydrocarbons decreases. The differences in the catalytic properties of high-silicon pentasils and mordenites in transformations of lower olefins are primarily due to the features of the structure of these zeolites, which determine their different stability in the conditions of a catalytic reaction.

Dehydration of 3-methyl-2-butanol on zeolites Y, mordenite, and entasil in the sodium and hydrogen forms and on dealuminated mordenites was studied. The hydrogen forms of zeolites from the pentasil family and dealuminated mordenite with a SiO{sub 2}/Al{sub 2}O{sub 3} ratio of 14 exhibit the highest activity. 3-Methyl-2-butanol is dehydrated on the zeolites not only according to the mechanism of {beta}elimination, but also according to the mechanism of {gamma}-elimination to a significant degree.

In the continuation of the study of the capacity of skeletal Cu-Pd catalysts modified with RR-tartaric acid and containing no more than 5 at.% Pd, to conduct enantioselective hydrogenation of ethylacetoacetate (EAA) into R-ethyl-{beta}hydroxybutyrate (R-EHB), they studied this phenomenon in more detail and made the previously obtained data more precise. Pronounced synergism of the asymmetric effect of chiral copper-palladium catalysts related to manifestation of a ligand effect was found.

The method of quasistationary concentrations in the kinetic description of free-radical decomposition of azobisisobutyronitrile in the presence of 1,2-bis-(4,4'-dimethylaminophenyl)-1,2-diphthaloylethane was experimentally substantiated. The catalytic activity of Co(III) acetylacetonate increases during decomposition of tert-butyl hydroperoxide, and the catalyst reacts with the tert-butylperoxyl radicals. The reaction of copper(II) acetylacetonate with the free radicals formed during catalytic decomposition of cyclohexenyl peroxide is accompanied by the disappearance of the EPR signal of the copper ions.

In tetrahydrofuran medium on a dropping mercury electrode, vanadocene dichloride undergoes reversible one-electron reduction to a metastable vanadocene dichloride anion on the first wave; this anion is reversibly dehalogenated in the layer near the electrode, forming vanadocene monochloride. On the second wave there is an irreversible one-electron reduction of vanadocene monochloride to vanadocene. The reversible one-electron reduction of vanadocene on the third wave leads to the formation of metastable anion Cp{sub 2}V{sup -} as the primary product. A general scheme is proposed for the electroreduction of metallocene dichlorides of subgroups IVB-VIB.

The general principles of the electrochemical chlorination of polynitrocarbanions of various structures were established, and it was shown that carbanions, more difficult to oxidize than chloride ions, are virtually quantitatively chlorinated on anodes of Pt, graphite, or on an oxide-ruthenium-titanium anode (ORTA). The formation of chloroderivatives of readily oxidized carbanions with a high yield is promoted by conducting the process on an ORTA electrode, by high values of the current density, and by high chloride ion concentrations.

1,2,2,5,5-Pentamethyl-3-imidazoline 3-oxide is an effective spin trap for short-lived free radicals, forming spin adducts with life time of > 10 min. Protonation of the amine N atom of imidazoline is manifested in the EPR spectra of the spin adducts, which makes it possible to measure pH in the range of 2.5 to 4.

A systematic investigation of the structure of the vinyl ethers of heterocyclic compounds has not been undertaken. The present work was devoted to investigation of the stereochemical and electronic structure of the vinyl ethers of pyridine and quinoline. The PMR spectra of the samples were recorded for 5% solutions in deuterochloroform on a Tesla BS-497 spectrometer at 100 MHz. The {sup 13}C NMR spectra were recorded on a Tesla BS-567A spectrometer at 25.1 MHz in deuterochloroform with the samples at concentrations of 30%. The internal standard was HMDS. The vinyl ethers of pyridine and quinoline exist preferentially in the nonplanar S-trans conformation. In the vinyl esters of pyridine and quinoline the p-{pi} conjugation is concurrent in nature and depends on the position of the vinyloxy group in the heterocycle.

The {sup 13}C NMR spectra of peroxide derivatives of cyclanes and cyclic peroxides have been investigated. Replacement of the exocyclic OH group by OOH for saturated cyclic systems leads to a displacement of the signals from the {alpha}-carbon downfield by 13.0 ppm, while the {beta}carbon is displaced upfield by 4.5 ppm, without any dependence on the size or conformational structure of the rings. Replacement of the transannular OO group by CH{sub 2}CH{sub 2} or CH{sub 2}O increases the shielding of the quaternary carbon adjoining it.

The authors have used NMR to study 4,4,7,7-tetramethyl-1,3-dioxepane, 2,2,4,4,7,7-hexamethyl-2-sila-1,3-dioxepane, and 2-oxa-4,4,7,7-tetramethyl-1,3,2-dioxathiepane. The proton and {sup 13}C NMR data are set out in tables. Proton NMR spectra were run on a Varian HA-100D spectrometer and carbon-13 spectra on a Bruker WH-90. The solvents used are noted. Concentrations were 1% for the proton spectra and 10-15% for carbon-13 spectra. 4,4,7,7-tetramethyl-1,3-dioxepane and 2,2,4,4,7,7-hexamethyl-2-sila-1,3-dioxepane exist in solution in the twist-boat conformation.

In the IR spectrum of solutions of vinylmethyltelluride in n-heptane the doublet form of the valence oscillation band of the double bond is due to rotational isomerism. By analyzing the temperature dependence of the doublet shape, the low-frequency component of the doublet was identified as the s-cis-rotamer. The differences in the enthalpies (4.6 +/- 0.2 kJ/mole) and entropies (-11.1 +/- 0.3 e.u.) of the vinylmethyltelluride rotamers have been calculated and it has been shown that the p,{pi}-conjugation in its molecule is weaker by a factor of 2 than in vinylmethylsulfide.

The authors examine three examples of the production of heptaprenol omega t{sub 3}ctcOH, dodecaprenol omega t{sub 3}c{sub 7}tOH, and also prenol omega t{sub 8}cOH on the basis of the previously developed stereospecific scheme of E/Z-C{sub 5} homologization of terpenols or their halides by means of the corresponding synthons.

In the Friedel-Crafts alkylation of benzene by normal 1-haloalkanes with three or more carbon atoms a mixture of phenylalkanes forms, due to isomerization of the alkyl chain and migration of a hydrogen atoms. Under analogous conditions the alkylation of benzene by omega-chloroalkanoic acids, Cl(CH{sub 2})/sub n/COOH, and omega-bromoalkanonitriles proceeds with isomerization of the alkyl chain, but beginning only with 6-chlorohexanoic acid and 6-bromohexanonitrile. Such a difference in the behavior of these halogen derivatives has not received a convincing explanation, although the mechanism of Friedel-Crafts alkylation of benzene should be the same in the two cases. For a better understanding of this difference, this work presents a systematic study of benzene alkylation by 4-chlorobutyric, 5-chlorovaleric, 6-chlorohexanoic, and 7-chloroheptanoic acids and their methyl esters and nitriles, and by {gamma}-butyro- and {delta}valerolactones. The catalyst was crystalline AlCl{sub 3} twice sublimed from Mg. For comparison, alkylation with the respective 1-chloroalkanes was carried out. In the alkylation of benzene by omega-chloroalkanoic acids Cl(CH{sub 2})/sub n/COOH (where n = 3-6) and their methyl esters and nitriles, in the presence of AlCl{sub 3}, the degree of isomerization of the alkyl chain is less than with the corresponding 1-chloroalkanes, depending on the increase in electron acceptor activity in the sequence HOOC- > CH{sub 3}OCO- > CN-.

During solvolysis of some complex esters of haloalkanols isomerization with halogen migration is observed for which an ion-pair mechanism has been proposed. In this work trifluoroacetolysis (TFA) of 2-bromoethyl-p-toluenesulfonate and 2-bromo-p-anisole-sulfonate was studied in order to explain the influence of the departing sulfonate group on the mechanism and kinetics of the reaction. The reaction was investigated by PMR. In order to monitor the bromine 1,2-migration a deuterated substrate was prepared. The CD{sub 3}O group serves to eliminate the MeO signal at 3.6 ppm thus simplifying the spectrum of the investigated compounds.

The organotitanium compounds RTi (OPr-i){sub 3} (R = Ar, Me) and RTi(NEt{sub 2}){sub 3} (R=CH{sub 2}=CH, PhCH=CH, CH{sub 2}=CHCH{sub 2}) react with allyl halides in the presence of palladium complexes under mild conditions to give the allyldemetallation products. In the case of RTi(OPr-i){sub 3} compounds, an efficient cross-coupling catalyst is bis ({pi}-allylpalladium chloride), whereas reactions involving RTi(NEt{sub 2}){sub 3} are catalyzed by tetrakis(triphenylphosphine)palladium.

The aim of this investigation was to examine the reactivity, stereo-, regio-, and chemoselectivity of aluminocuprate reagents obtained from copper salts and aluminum trialkyls in their reactions with monosubstituted acetylenes.

In a continuation of the study of catalytic reactions in which small molecules participate they have examined the reaction of butadiene simultaneously with CO{sub 2} and NH{sub 3} in the presence of homogeneous Pd-containing catalyst complexes with the object of developing a single-step method for the synthesis of unsaturated higher formamides. The possibility of joint catalytic activation of small molecules (CO{sub 2} and NH{sub 3}) has been demonstrated in their reaction with butadiene with the participation of palladium complexes, the products being mono- and bis-(2,7-octadienyl)formamides. It has been found that 2-pyrrolidone can take part in a telomerization reaction with butadiene in solutions containing palladium complexes, ammonia and carbon dioxide with the formation of N-2,7-octadienylpyrrolidone.

In order to develop an efficient method for the synthesis of higher order unsaturated tertiary amines, and also to explore a new method for the formation of C-N bonds, they have investigated the transition metal complex-catalyzed reaction of magnesium amides with electrophiles; the electrophiles selected for study included allyl ethers and esters, as well as sulfones, sulfides and quaternized allylamines. The effects of the nature and structure of the catalyst components, as well as of the reaction conditions, on product yield were examined in the case of the reaction of diethyl (bromomagnesium)amine with diallyl ether, and revealed that the highest yield of diethylallyl-amine (I) was achieved using Pd(acac){sub 2} (3-5 mole %) and Ph{sub 3}P (1:2) as catalyst in THF solution at 50{sup 0}C for 5 h. Other transition metal (Ni, Fe, Zr, Ti, Cu) compounds were also examined as catalysts, but the yield of (I) did not exceed 15% with these compounds. Bimetallic catalysts based on Zr (Cp{sub 2}ZrCl, Py{sub 2}ZrCl{sub 6}, (RO){sub 4}Zr) and Ni (Ni(acac){sub 2} and NiCl{sub 2}) were successful in forming (I) from diethyl (bromomagnesium)amine and diallyl ether in 60% yield.

Previous reports have described the synthesis of carbonyl compounds based on the reaction of CO with simple Mg and Sn-organic reagents in the presence of Ni- and Pd-containing catalysts. In order to explore the potential of this approach for the synthesis of unsaturated sulfides, they have investigated the cross-coupling of alkenylmagnesium halides, obtained via the hydromagnesionation of isoprene, with allyl ethers and esters in the presence of elemental sulfur (S{sub 8}, cyclooctasulfane), catalyzed by transition metal complexes. Their experiments revealed that in order to carry out these types of reactions it was necessary to use two and three-component catalyst systems based on Pd compounds (Pd(acac){sub 2}, PdCl{sub 2}) in conjunction with Ph{sub 3}P, as well as AlET{sub 3} or i-Bu{sub 2}AlH.

They have synthesized the novel cyclopendant complexon 1,5,8,12-tetrakis(dihydroxy-phosphorylmethyl)-1,5,8,12-tetraazacyclotetradecane and studied its acid-base and complexing properties. The prepared compound is characterized by high selectivity of complex formation with respect to the copper (II) ion.

The authors have studied the reactions of phenylbis(hydroxymethyl)phosphine sulfide (PHPS) with acetals and ketals. {sup 31}P NMR Spectra were recorded at 10.2 HMz on a KGU-4 spectrometer with proton noise decoupling at 25.2 MHz. Chemical shifts are given relative to 85% H{sub 3}PO{sub 4} (negative values to higher field). PMR Spectra were measured on a Varian T60 machine at 34.5{sup 0}C. Treatment of phenylbis(hydroxymethyl)phosphine sulfide with acetals and ketals gives the corresponding 2-substituted and 2,2-disubstituted 5-phenyl-5-thio-1,3,5-dioxaphosphorinanes in which the P-Phenyl substituent occupies an axial position.

It is shown that the thermally stable (to 300-400{sup 0}C) transition metal glycolates, glycerates, and pinacolates could be obtained from bisarenyl, cyclopentadienyl, and carbonyl metal compounds by reaction with polymeric alcohols. At 150-180{sup 0}C monomeric compounds are formed; these are converted to polymeric products above 200{sup 0}C. When two glycolates react with various metals or when glycolates react with organometallic compounds, new, mixed complexes of a polymeric nature are obtained.

The rearrangement of pennogenin 3,17-diacetate under the action of BF{sub 3} x Et{sub 2}O gives the following products: 20S, 22R, 25R-16{alpha}, 17{alpha}, 22-(1',1',1'-ethylidenetrioxy)-22,26-epoxy-cholest-5-ene-3{beta}ol-3-acetate and 20S, 25R-16{alpha}-0.17{alpha}-0.23-(1',1',1'-ethylidenedioxy-22,26-epoxycholest-5,22-diene-3{beta}ol-3-acetate. Acetylation of C{sup 17}{alpha}-OH in the 25R-spirostan series leads to anomalously large effects on the values of chemical shifts of the {sup 13}C(C{sup 16}) and {sup 1}H(H{sup 16}) nuclei in their {sup 13}C and {sup 1}H NMR spectra.

The reactions of Co{sub 2}(CO){sub 8} with arenes in hexane gave arenecarbonyl clusters, ArenCo{sub 4}(CO){sub 9} including products with functional substituents in the side chain. The reactions of these products with nucleophiles and electrophiles were studied. The photochemical replacement of CO by PPh{sub 3} gave Me{sub 3}C{sub 6}H{sub 3}Co{sub 4}(CO){sub 8}PPh{sub 3} and the chemical properties of this product were studied.

1-phenyl-4,4-dimethyl-1,4-phosphasilacyclohexane was formed upon the photochemical addition of phenylphosphine to dimethyl(divinyl)silane and gave 1-phenyl-4,4-dimethyl-1-seleno-1,4-phosphasilacyclohexane upon reaction with elemental selenium. NMR spectroscopy indicated that 1-phenyl-4,4-dimethyl-1,4-phosphasilacyclohexane and 1-phenyl-4,4-dimethyl-1-seleno-1,4-phosphasilacyclohexane exist in the chair conformation with predominance of the conformer with axial orientation of the unshared electron pair of the phosphorus atom.

The phase equilibrium coefficients as functions of mixture composition were used to analyze product areas and the areas where complete fractionation are possible given reversible and adiabatic rectification. The possible structures of the path families for reversible rectification were generated.

Models of the flow structure in equipment with recycle including zones of mixing and displacement, one of which is a recycle line, are analyzed.

The method of separation of variables is used to find the expression for efficiency - the basic characteristic of a contact matrix heat-exchanger and recuperator. The authors have numerically obtained the dependence of efficiency on length for a number of limiting cases and, on this basis, constructed a method of calculating the heat-exchange apparatus.

A method was developed for the calculation of the maximum possible temperature-time parameters and the extent of vulcanization during vibroextrusion of rubber mixtures.

The authors obtain a closed system of differential equations for the turbulent transport of suspended particles in flowing aerodispersed and hydrodispersed media which can be used to calculate the average velocity distribution of the particles and the carrier medium and also the concentration distribution of particles over the cross section of a channel, pipe or open flow channel.

A procedure has been developed for selecting the structural design of chemical reactors based on a three-level optimization algorithm that employs an effective cost criterion. The maximum reactor productivity is calculated under conditions in which an optimum temperature profile is realized in the catalyst bed. Results are given for the optimization of the design parameters of multiple-tray catalytic reactors for the joint synthesis of methanol and higher alcohols.

A mathematical description of the dynamics of a rectification column has been developed for a specific pilot plant. It was shown experimentally that kinetic and hydrodynamic coefficients found for stable regimes can be used in the model and that a dynamic model incorporating these coefficients adequately describes a real instable process.

A mathematical model of a rotary granulator drier is developed taking into account lengthwise mixing of the solid phase. Equations that describe the granulation kinetics and which can be used to determine the grain-size composition of the product are derived.

A mathematical model of the roasting of sulfides in an industrial furnace was designed. It describes the process in the fluidized bed and in the space above the bed and can be used to calculate the yield parameters under widely varying feed conditions.

The operating regime of an adiabatic displacement-type chemical reactor with recycle was studied. A region of stability of steady-state regimes was identified in the parametric space.

The optimum design of a stage of an ideal-mixing chemical reaction vessel with an exothermic reaction is analyzed with allowance for stability limitations. It is shown that, through an optimum choice, one can considerably reduce the number of steps required to assure a stable steady-state regime, in contrast with the equilibrium distribution that is often used. An efficient algorithm for the suboptimum choice of the contact-time distribution is proposed for the case of one reaction and two parallel reactions with first-order kinetics.

The mean thickness of a film falling under gravity in a channel with regular roughness was determined experimentally by the method of electrical conductivity. Relationships for calculating the film thickness were obtained.

The main aspects of the hydrodynamic similarity have been formulated as applied to porous systems, based on the pseudosimilarity of the structures and the similarity of hydrodynamic processes. Definitions are given of the pseudolaminar and pseudoturbulent flow regimes in porous systems and of their principal difference from laminar and turbulent flow regimes in pipes and channels.

A graphical representation of the possible variants of a centrifugal filtration process has been employed to construct an algorithm for calculating the process parameters.

A model has been proposed and tested for the process of loose material mixing in the cross section of a smooth rotary drum.

Modeling of granulation processes in drum granulators is discussed. Densification and abrasion of granules and adhesive deposition of the powder on the drum's surface are taken into account.

An analysis is made of a step-by-step solution of the problem of static optimization of the operating parameters of a fractionation apparatus as a complex system of chemical engineering with allowance for the specifics of the fractionation process.

The initial rate of PP{sub 1} hydrolysis by inorganic pyrophosphatase from baker's yeast was analyzed as a function of the concentrations of the Mg-PP{sub 1} complex (substrate) and Mg{sup 2+} ions (activator) at substrate concentrations down to 0.1 {mu}M. Lineweaver-Burk plots for the enzyme in equilibrium with Mg{sup 2+} ions were nonlinear at fixed Mg{sup 2+} concentrations, which cannot be explained within the framework of previously proposed models of the reaction. The nonlinearity is retained for the monomeric form of the enzyme and indicates that the enzyme has a regulatory site capable of tightly binding free PP{sub 1} (K/sub d/ {similar_to}0.02 {mu}M). A new model of the reaction is proposed in which Mg-PP{sub 1}, PP{sub 1}, and Mg{sup 2+} are bound to the enzyme in random order and filling of the regulatory site decreases the dissociation constant of the protein-Mg complex from 4.7 to 0.025 mM. It was concluded that PP{sub 1} and Mg{sup 2+} are regulators of pyrophosphatase activity under physiological conditions.

The effect of four PP{sub 1} analogs with the structure PXP (X = N, C), phosphate, and the complex Cr(H{sub 2}O){sub 4}PP{sub 1} on the activity of inorganic pyrophosphatase from baker's yeast was studied over a wide range of substrate (Mg-PP{sub 1}) concentrations (lower limit 0.5 {mu}M). The enzyme activity decreased in the presence of imidodiphosphate, hydroxymethane diphosphonate [PC(OH)P], and P{sub 1}, and a double reciprocal plot of the rate of hydrolysis of Mg-PP{sub 1} versus its concentration became linear. Small amounts of methane diphosphonate (PCP), ethane-1-hydroxy-1,1-diphosphonate (0.1-1{mu}M), and Cr(H{sub 2}O){sub 4}PP{sub 1} (10 {mu}M) activated the enzyme almost 2-fold by a competitive mechanism. The activation was due to an increase in the affinity of the protein for the activating Mg{sup 2+} ion. Ultrafiltration showed that the pyrophosphatase molecule has 2.1 and 3.1 binding sites for PCP and PC(OHP)P, respectively. These results confirm the hypothesis that the enzyme contains a regulatory site whose occupation by PP{sub 1}, P{sub 1}, and substrate analogs increases the affinity of the protein for the activating metal.

Quinate dehydrogenase was isolated from young needles of the Siberian larch and partially purified by ammonium sulfate fractionation. It was found that in conifers, in contrast to other plants, quinate dehydrogenase is active both with NAD and with NADP. The values of K/sub m/ for quinate and NADP were 1.8 and 0.18 mM. The enzyme exhibits maximum activity at pH 9.0. It was assumed that NADP-dependent quinate dehydrogenase is responsible for quinic acid synthesis. The special features of the organization and regulation of the initial stages of the shikimate pathway in conifers are discussed.

The isolation and a preliminary characterization of the enzyme specifically hydrolyzing the phosphodiester bond between protein VPg and the RNA of encephalomyocarditis virus was the goal of the present investigation. The enzyme was isolated from a salt extract of Krebs II mouse ascites carcinoma cells by ion-exchange and affinity chromatography. It was found that the enzyme actually specifically cleaves the covalent bond between the RNA and protein, however, the isolation procedure does not free the enzyme from impurities which partially inhibit it. The enzyme cleaves the RNA-protein VPg complex of polio virus at a high rate, it is completely inactivated at 55{sup 0}C, and is partially inhibited by EDTA.

A lysate of human erythrocytes was fractionated on gel-filtration resins of different types and immunoreactive insulin, the insulinase activity and the effect of individual fractions on the insulinase activity was determined in the fractions obtained. It was established that the hemolysate contains a complex of insulin-metabolizing compounds, including an insulin-like substance, insulinase, and an inhibitor and activator of the insulinase activity. The insulin-like substance coincided with native insulin in site of elution from a column of

Sephadex G-50 and its concentration in the lysate exceeded that of insulin in the blood plasma. Insulinase, which has a molecular weight of about 100,000, cleaved [{sup 125}I] insulin to fragments soluble in trichloroacetic acid, but had no effect on hypophyseal proteins and glycoprotein hormones. The insulinase activity was inhibited by low temperatures, atropine, and a newly discovered intraerythrocytic proteinase inhibitor, which also inhibits the serine proteinases trypsin and chymotrypsin. A substance eluted from a column of Sephadex G-100 in the region of low-molecular-weight substances increased the insulinase activity. The elution curve of substances with proteinase-inhibiting and insulinase-activating activities indicates that there is more than one inhibitory and activating factor. The results of the studies suggest that the insulin-degrading complex in human erythrocytes acts as a regulator of the insulin level in the blood plasma. It is also possible that the insulin-like substance is produced in the cytosol of the erythrocytes.

After incubation of wheat seedlings with [{sup 3}H]benzylaminopurine or [8-{sup 3}H]zeathin appreciable radioactivity was found in the purine bases of DNA, mainly in adenine. Moreover, as a result of acid hydrolysis labeled cytokinins were isolated from labeled highly purified preparations of the total DNA of wheat seedlings. Their radioactivity constituted 5-10% of the radioactivity of the adenine bases in the DNA. After mild acid hydrolysis [{sup 3}H]benzylaminopurine and [{sup 3}H]zeathin were found in the deoxyribonucleoside fraction obtained from cytokinin-labeled DNA. Thus, different cytokinins (N{sup 6}-substituted adenine derivatives) are covalently incorporated into the newly synthesized DNA of plants.

Hormonal activation of the adenylate cyclase complex is associated with lateral displacement in the membrane of the proteins that constitute this complex. In this work an experimental investigation was made of the changes in the interaction of the proteins of the adenylate cyclase complex with the changing fraction of fluid lipids in the cell membrane. A decrease in the fraction of fluid lipids of rat reticulocyte membranes led to a decrease (all the way down to a total suppression) of the interaction of the {beta}adrenoreceptors with the regulatory N-proteins. The interaction of the N-proteins with the catalytic proteins was also suppressed. On the other hand, an increase in the fraction of fluid lipids led to more effective interaction. It was shown that in this case the functional intactness of the interacting proteins is unimpaired. An analysis of the results obtained, performed on the basis of the percolation theory, suggests the conclusion that the hormonal stimulation of adenylate cyclase depends on the fraction of fluid lipids in the membrane, and the proteins are displaced during interaction over distances comparable with the size of the membrane itself. It was also shown that characteristic activity of the {beta}agonist 1-isoproterenol varies from 1.0 to 0, depending on the fraction of fluid lipids in the membrane. The data obtained suggest that in the absence of guanylic nucleotides in the membrane in vitro there are no preexisting complexes with a high affinity for the agonist.

The activity of three enzyme systems of xenobiotic metabolism: cytochrome P-450-dependent monooxygenases, nonspecific esterases, and glutathione S-transferases, was investigated on a sensitive strain (S) of the housefly M. domestica L. and strains resistant to tetrametrin (R/sub tetr/), permetrin (R/sub perm/), mecarbenyl (R/sub mec/), and chlorophos (R/sub chlor/). In the strains R/sub tetr/ and R/sub mec/, in comparison with strain S, an increase of 2.7 and 2.3-fold, respectively, in the activity of microsomal monooxygenases was observed. The position of the maxima of the CO-differential spectra of cytochrome P-450 in all the investigated resistant strains, with the exception of R/sub chlor/, is shifted by 1-2 nm in the shortwave direction. The activity of glutathione S-transferases in the strain R/sub tetr/ proved elevated in comparison with the strain S. The data of an investigation of the total esterase activity and the data of starch gel electrophoresis are evidence of quantitative and qualitative differences between the strains. For all the resistant strains except for R/sub mec/, supplementary zones of esterase activity appear. The data obtained are discussed in connection with the resistance of the insects to insecticides.

The activity of three enzymes systems of xenobiotic metabolism - cytochrome P-450-dependent monooxygenases, nonspecific esterases, and glutathione S-transferases - was investigated at various stages of the development of the Colorado beetle Leptinotarsa decemlineata. Substantial sex and ontogenetic differences in the content of cytochrome P-450, the position of the maxima of the CO-differential spectra of its reduced form, and the substrate specificity of cytochrome P-450 were demonstrated. An increase in the activity of nonspecific esterases with increasing age of Colorado beetle larvae was observed. The insecticide 1-naphtholenol methylcarbamate, which is metabolized by the system of cytochrome P-450-dependent monooxygenases, is more toxic at the larval stage of development in comparison with the imaginal stage, which is in good agreement with the activity of this system at different stages of development. The inhibitor of microsomal monooxygenases piperonyl butoxide more than doubles the toxicity of the insecticide in the Colorado beetle imago. The data presented are evidence of a different contribution of the systems of detoxification to the sensitivity of the Colorado beetle to insecticides at different stages of metamorphosis.

It was shown on leukemia P-388 cells that a change in the intracellular Na{sup +}/K{sup +} ratio leads to a change in the qualitative composition of the newly synthesized mRNAs, which was recorded according to the change in the kinetics of hybridization of heterogeneous nuclear RNA (hnRNA) with DNA. A decrease in the intracellular Na{sup +}/K{sup +} ratio from 3.8:1 to 1:1 leads to inhibition in the cells of the synthesis of mRNAs that hybridize with DNA at 10{sup 3} > D/sub o/t > 10{sup 4} but has little effect on the transcription of the mRNA sequences that hydrolyze with DNA in the range of D/sub o/t from 10/sup 3 x 4/ to 10/sup 3 x 8/. An analogous picture is detected in the hybridization of hnRNA with homogeneous fractions of unique and medium-repetitive DNA sequences. The rate constants of hybridization of hnRNA synthesized by the cells at various ratios of cations and the limiting values of the degree of hybridization (H/sub {infinity}) were calculated. It was shown that the rate constants of the hybridization of RNA with DNA decrease by more than two orders of magnitude as they go from the fraction of medium repetitive DNA to the single-copy DNA, but in both cases the values are the same for the RNAs synthesized by the cells in the case of various cationic balances.

Heating of Chinese hamster fibroblasts at 46{sup 0}C for 10 min profoundly inhibits protein biosynthesis in the homogenate, nuclei, and to a lesser degree in the nuclear matrix. The ratio of the specific radioactivity of [{sup 35}S]-proteins of the nuclear matrix to the corresponding radioactivity of a homogenate, taken as 100%, increases by a factor of 2.5 after heat shock. Thus, the biosynthesis of proteins of the nuclear matrix is more resistant to the injurious action of heat shock than the biosynthesis of proteins of the homogenate and nuclei. Heat shock proteins with molecular weights of 84-86, 70, and 26 kilodaltons were detected in the nuclear matrix. The 70 kilodalton polypeptide-predominates. This polypeptide is detected after 4 h, is intensively accumulated by 6h, and is preserved for up to 17-24 h after heating of the cells. The 70 kilodalton heat shock polypeptide is separated by two-dimensional electrophoresis into two subfractions, differing in pI value from the other proteins detectable in this region in the unheated cell.

Certain biochemical mechanisms underlying the impairment of cellular immunity were studies on models of transplanted and orthoaminoazotoluene-induced solid hepatomas in C{sub 3}HA mice. In the thymocytes of the mice, by the beginning of rapid growth of the hepatomas, a significant decrease in the adenosine deaminase was detected, six fold relative to the control, resulting in a corresponding 6-7-fold increase in the intracellular concentration of dATP and dGTP, potential inhibitors of ribonucleoside diphosphate reductase. These disorders were accompanied by inhibition of DNA synthesis, recordable according to the decrease in the thymidine kinase activity, the rate of incorporation of [{sup 14}C]thymidine into the thymocyte DNA in vitro, and the pool of dTTP and dCTP. At the terminal periods of growth of transplanted and induced hepatomas, 3- and 8-fold increases in the corticosterone concentration in the blood serum of the

tumor-bearing animals were detected, respectively. An increase in the specific binding of [{sup 3}H]triamsinolone acetonide by the thymocytes and an increase in their terminal deoxynucleotide transferase activity were also established, which, among other indices, reflects a lag in the differentiation of T-lymphocytes at the level of the cortical thymocytes.

The metabolism of various classes of histones and nonhistone proteins in whole nuclei and liver chromatin of albino Wistar rats 1, 3, 12, and 24 months of age was studied. It was shown that in the course of postnatal ontogenesis, the metabolism of nonhistone proteins, extractable by a 0.14 M solution of NaCl, is increased in the animals. The incorporation of labeled precursors into the HMG 14 and HMG 17 proteins decreases with age of the animals; a higher level of specific radioactivity was established for the HMG 1+2 proteins in the 3- and 24-month old animals. The intensity of the metabolism of nonhistone proteins and histones is higher in the chromatin complex than in the whole nucleus at all stages of postnatal development of the animals. Among the histone proteins, H1 histones possess a higher level of specific radioactivity in animals of all age groups.

It was established that IgG isolated from the sera of healthy humans contains a substantial number of antibodies that react with native DNA. Their ability to interact with DNA is manifested only after chromatography on an anion exchange resin, as a result of which IgG is divided into two portions - acid and basic immunoglobulins. The peculiarities of the interaction of both fractions with DNA and the specificity of this reaction were investigated. It was shown that the investigated IgG can react with native and denatured DNA, dextran sulfate, poly(G), and poly(I). The question of the possibility of the interaction of the antibodies studied with the charged structures of the cell and that of the role of these antibodies in the normal and pathological states are discussed.

When five structurally different inducers of the MC type (polycyclic aromatic and heterocyclic hydrocarbons, chloro-derivatives of biphenyl and dibenzo-p-dioxin) are introduced into Wistar rats, de novo synthesis of two P-448 hemoproteins (M/sub r/ 56,000 and 53,000), differing in their functional and immunological parameters, occurs. A comparison of the catalytic and immunochemical properties of five cytochromes P-448 (M/sub r/ 56,000), the data of electrophoretic, proteolytic, and inhibitor analyses did not reveal any differences in the preparations compared, with the exception of TCDD-microsomes, where a low content of this form of cytochrome P-448 and high molecular activity of it with respect to 3,4-benzpyrene and 7-ethoxyresorufin were demonstrated. The results obtained do not support the hypothesis of the possibility of induced synthesis of such a variety of individual forms of monoxygenases as would correspond to the number of variants of the chemical structure of the xenobiotic inducers.

The biosynthesis of fibronectin by human embryo fibroblasts, transformed by SV-40 virus, was investigated in intact cells and in a cell-free protein-synthesizing system on free and membrane-bound polyribosomes, isolated from the same cells. It was shown that fibronectin production in the culture medium by transformed fibroblasts is reduced by a factor of 4.5, while its percent content in the medium is decreased by a factor of 2. The content of fibronectin material precipitable by antibodies during the immunoprecipitation reaction proved to be somewhat greater in transformed cells than in normal cells, although the percentage was decreased by a factor of 1.5. However, the content of the fibronectin monomer with molecular weight 220 kilodaltons was 1.6 times as great in the cellular material of normal fibroblasts. In an investigation of fibronectin biosynthesis in a cell-free system it was established that in transformed cells 45% of the fibronectin is synthesized on free polyribosomes; in normal fibroblasts only 13% of the fibronectin is synthesized on free polyribosomes. It is suggested that one of the consequences of the transformation of human fibroblasts by SV-40 virus, leading to a decrease in fibronectin production, is the spatial uncoupling of the polyribosomes and membrane structures responsible for protein transport out of the cell, as a

result of which a substantial portion of the fibronectin synthesized by transformed fibroblasts is subjected to intracellular degradation.

For many years, the Lower Cretaceous Sunniland oil-producing fields have been interpreted as reef deposits. Petrologic evidence from cores from field and wildcat wells strongly indicates on the basis of faunal composition and character, that the fields are producing from moundlike shoals. These shoals are considered to have been deposited in a mudflat environment similar to that of present-day Florida Bay. This present-day Florida Bay analog is used to determine the various environmental subzones and controls on the deposition of the Sunniland Formation. This concept of using a model together with a modern analog can be a powerful tool in the exploration of stratigraphic traps. A petrologic and petrophysical study of the Sunniland Formation in the wells that have been drilled in the Florida Bay and Keys areas was made to extend the model and its application throughout the South Florida basin. The evaluation of these wells has produced new insights into the tectonics of this basin and its relationship to the Bahamas and Caribbean areas.

A computerized two dimensional dynamic model was used for basin analysis to simulate fluid flow, heat transfer, and petroleum generation and migration processes in an offshore oil field of an evolving sedimentary basin. Through the application, they confirmed that the results from the model can be used to estimate the timing and amount of petroleum generation and migration consistent with downhole data. Although the estimates carry uncertainties (produced predominantly by lack of knowledge of some geologic parameters), nevertheless, they were able to bound the range of the uncertainties, using the model as an experimental tool. Such effects are slightly different in using a two-dimensional model versus a one-dimensional model. Dominant parameters most influenced pertain to reservoir character, such as porosity, permeability, shaliness, and geometry. Sensitivity testing elucidates the differences in the one- and two-dimensional fluid flow and compaction models, and provides conditions for the relevant application arenas for each model.

Rock-forming buildups of larger foraminifera, though not unknown in Louisiana, are rare, and are less common in the Gulf Coast than in Eocene strata from the Tethyan and Caribbean regions. In strata from the upper Wilcox Group (lower Eocene) in Pointe Coupee Parish, Louisiana, they have identified a thin, very rich faunal deposit, or bank made up almost exclusively of the tests of the larger foraminifera species, Pseudophragmina (Proporocyclina) zaragosensis. This is the first report of P. (P.) zaragosensis from the Louisiana Wilcox Group. The bank fauna colonized the sand sea floor on the continental shelf, flourished briefly, and then gradually declined, probably in response to increasing water depth, caused either by compaction-induced subsidence and/or a local or regional rise in relative sea level. This bank indicates that, during late Wilcox deposition, warm, shallow continental-shelf conditions prevailed in this region.

The effects of abrasion on the shapes of medium and fine quartz sand grains that are transported through a 300-mi (500-km) stretch of the Mississippi River were determined by Fourier grain-shape measurement and scanning electron microscopy. The results indicate that the abrasion of medium and fine quartz sand grains in the low-gradient stream does not significantly affect their source-inherited shapes.

The effect of shaliness on sand quality is of great importance in the evaluation of Gulf Coast and offshore reservoirs. Shaliness needs to be determined so that proper hydrocarbon producibility potentials can be assessed for economic and completion decisions. The use of thermal and epithermal neutron measurements, in conjunction with standard methods, increases the accurate measurement of shaliness in Gulf Coast formations.

The shallow upper Frio producing trend along the downthrown side of the Vicksburg flexure in the lower Texas Gulf Coast is one of the world's supermature provinces for oil and gas exploration. Current emphasis in exploration must be for the subtle trap, the discovery of which has been

precluded during the many years of intensive exploration. East Taft field is an excellent example of one such subtle trap. A stratigraphic oil accumulation in a barri-bar washover sand, East Taft field had produced 2.35 million bbl of oil from 33 wells completed in an average of only 2.5 ft (0.76 m) of net oil sand. Traps of this type are numerous all along the trend, owing to the nature of the barrier-bar and adjacent lagoonal environments. These traps remain largely undiscovered, as they are never specifically explored for, and are commonly passed over as noncommercial when penetrated by wells. The economic potential of these subtle traps is enormous. Exploration programs geared specifically toward finding these reserves can be expected to provide an excellent return on investment. However, creative geological thinking and innovative engineering practices are requisite to the discovery and profitable development of these fields. For the explorationist who is willing to do the detailed structural and stratigraphic analysis required to identify these prospects, who understands the risks involved in exploration for these traps, and who is willing to innovate, these subtle stratigraphic traps truly represent a new frontier in an old producing province.

Forty-four core samples from three wells drilled into the Dorcheat and Hosston formations in northern Louisiana were examined for fossil palynomorphs. These samples were obtained from the four beds of the Dorcheat formation, and from the lower two beds of the Hosston Formation. A diverse terrestrial and marine palynoflora containing stratigraphically significant species indicates that the cored section of strata spans the Jurassic-Cretaceous boundary.

Since its discovery in 1983, there have been eight deep Wilcox and eight Queen City wells drilled in the Travis Ward field area. Of the eight Wilcox wells, four are producing gas from deep sands; three, that are capable of production, have been junked and abandoned, and one produces from the Hinnant sand at the top of the Wilcox. Only five of the eight Queen city wells have been completed; three are considered commercial. Wilcox gas reserve estimates range from 80 to 300 bcf. To date, Wilcox and Queen City production is related to normal faulting associated with a deep salt and/or shale ridge within the Rio Grande interior salt basin. Growth of the ridge has resulted in the Wilcox being as much as 2000 ft structurally higher than the areas immediately north and south of Travis Ward field. Knowledge of the ancestral development of ridge closure prior to faulting may be critical to successful completions at Travis Ward field. Ridge-associated sea floor topography, shelf currents, sediment source proximity, and rate of sedimentation have combined for local development of high quality clean reservoir sands.

The Upper Jurassic Norphlet sandstone of the northern Gulf Coast is predominantly subarkose, with some arkose in the eastern area and sublitharenite and quartzarenite in the western area. Despite great depths of burial and despite feldspar and rock-fragment constituents, diagenesis has not appreciably altered the composition of Norphlet sandstone. Therefore, reconstruction of original composition of Norphlet sandstone presented little difficulty. Variation in detrital modes of the Norphlet suggests compositionally distinct source terranes. Samples from Florida, Alabama, and Mississippi reflect the influence of metamorphic and plutonic rocks of the Appalachian Piedmont Province and of Triassic-Jurassic volcanic rocks. Sandstones in east Texas, northern Louisiana, and southern Arkansas were derived from sedimentary and metasedimentary rocks of the Ouachita system. The Arbuckle Mountains and Llano uplift may have supplied trace amounts of quartzo-feldspathic and volcanic-rock fragments to the extreme western part of the study area. Norphlet sandstones represent a mixture of collision-orogen-derived sediment from the Appalachian and/or Ouachita system and continental-block-derived sediment from paleohighs and uplifts within the Gulf basin. However, Norphlet sandstones plot in the craton-interior and transitional-continental fields on Q-F-L and QM-F-Lt tectonic-provenance diagrams, because of mineralogically mature source rocks, elimination of unstable grains by abrasion and sorting during deposition, and/or sediment mixing from different source terranes.

The main source for crude oil in the Mississippi salt basin is the laminated lime mudstone facies of the lower Smackover. Crude oil generation and migration commenced at a level of thermal maturity equivalent to about 0.55% vitrinite reflectance. Short-range lateral migration of crude oil was focused on upper Smackover and Norphlet reservoirs, but vertical migration also charged some overlying Cotton Valley, Rodessa, lower Tuscaloosa, and Eutaw reservoirs. Following migration from the lower Smackover, thermal maturity history of reservoir rocks controls the preservation of crude oil, gas condensate, and methane. Slow thermal cracking of crude oil occurred in deep upper Smackover reservoirs, resulting in formation of gas condensate and precipitation of solid bitumen. The maximum thermal maturity for preservation of condensate is equivalent to about 1.3% vitrinite reflectance. Only methane, pyrobitumen, and nonhydrocarbon gases, including hydrogen sulfide, persist at higher levels of thermal maturity. Early destruction of methane in deep upper Smackover reservoirs near the Wiggins arch is driven by thermochemical sulfate reduction. Lesser availability of sulfate in Norphlet reservoirs could account for methane preservation at higher levels of thermal maturity. One basic geochemical strategy for further exploration of the Mississippi salt basin is to focus exploration effort on traps with reservoirs in the thermal maturity window for hydrocarbon preservation. Another strategy is to avoid drilling traps with overmature reservoir rocks.

Three shoaling-upward cycles were identified in the upper Smackover at Eustace field. Shoaling cycles ended during minor regressive stages. Each successive cycle was more widespread than the previous. Four depositional environments were defined: (1) shoal crest, (2) shoal flank, (3) back shoal, and (4) open marine. The shoal crest and flank environments are represented by ooid grainstones and ooid pisolite grainstones, respectively. Ooid-pellet grainstones and packstones were deposited in the back-shoal environment, whereas skeletal-pellet packstones were deposited in the open marine environment. The burial diagenetic history can be traced from early to late by the occurrences of the following events: micritization, formation of nodular anhydrite, isopachous rim cement, seepage reflux dolomitization, selective leaching, coarse sparry calcite cement, stylolites, saddle dolomite, pyrobitumen, quartz overgrowths, replacive anhydrite, and late leaching. Two porosity types are present at Eustace field: intercrystalline dolomite and oomoldic. Dolomitization occurred early and is the principal reason for the development of reservoir-quality porosity and permeability; it was selective for ooid-pellet grainstones and packstones of the back-shoal environment. Oomoldic porosity, which formed concurrently or slightly late than dolomitization, is not as extensively developed. Several agencies have reduced porosities and permeabilities in the field; they include saddle dolomite cement, sparry calcite cement, and pore-filling pyrobitumen (dead oil).

Through several decades of research on Foraminiferida, and revision of generic and suprageneric classification, the nature of coiling patterns and other modes of growth and their proper role in interpreting shell architecture generally have been misunderstood. Much of this confusion is due to the poorly chosen or unfortunate descriptive language used in earlier classifications. Biseriality and triseriality are, in fact, spiral growth patterns. The radius and the amplitude of the spiral in conjunction with chamber diameter and the rate of increase in chamber size are among the most important factors affecting shell architecture, especially in forms with helical growth patterns. The nature of the abrupt change in chamber addition that occurs between the final chamber in the juvenarium and the first added in the adult series of chambers should be recognized as another primary factor in generic discrimination and classification. More accurate and meaningful description of shell architecture and growth modes will greatly enhance the understanding of generic and suprageneric differences among professional micropaleontologists, as well as assist the beginning student.

The De Queen Limestone (Comanchean, Cretaceous) in the main Highland Gypsum quarry at Highland, Arkansas, consists of gypsum, limestone, and clastic sediments deposited along the landward margin of a broad, restricted, shallow

lagoon. It grades downdip into the Ferry Lake Anhydrite. Gypsum, in the form of satin spar, selenite, and alabaster, is abundant in the lower part of the section. Limestones ranging from lime mudstones to grainstones contain fossil mollusks, ostracods, serpulid worm tubes, and foraminifera. The gypsum and limestone lithologies are interbedded with claystones and shales. Strontium concentration was determined on about 100 samples by x-ray fluorescence spectrometry (XRF) and was found to be controlled by diagenesis, not deposition. Strontium concentrations in the gypsum are likely controlled by the rate of recrystallization of secondary anhydrite. Levels of strontium in the limestones reflect the amount of celestite cement. The strontium content of the clastic beds correlates with the amount of strontium-rich microcrystals of strontianite, celestite, barite, and witherite.