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November 1996

Lawrence

Livermore

National

Laboratory

Science &

Technology Review

Lawrence Liverm

ore National Laboratory

P.O.B

ox 808, L-664Liverm

ore, California 94551

Printed on recycled paper.

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it No.154

ConflictSimulationsSaving Time,Money, and Lives

Also in this issue: • The Secrets of Crystal Growth• A New way to Produce TATB• DNA Sequencing

About the Review

Since the early 1970s, Lawrence Livermorescientists have been developing interactivecomputer programs to simulate conflict situationsfor military training and planning. Today, thesehighly complex simulation models are used notonly for battlefield exercises but also for securitypurposes (such as planning the PresidentialInauguration), disaster relief, hostage rescues,and drug interdictions, to name but a few.Pictured on this month’s cover are Hal Brand(foreground) and Gary Friedman working withthe Joint Tactical Simulation model developed inthe Laboratory’s Conflict Simulation Laboratory.S&TR’s report on recent developments incomputerized conflict simulation technology andtheir contributions to national safety and securitybegins on p. 4.

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About the Cover November 1996

Lawrence

Livermore

National

Laboratory

ConflictSimulationsSaving Time,Money, and Lives

Also in this issue: • The Secrets of Crystal Growth• A New way to Produce TATB• DNA Sequencing

Lawrence Livermore National Laboratory is operated by the University of California for theDepartment of Energy. At Livermore, we focus science and technology on assuring our nation's security.We also apply that expertise to solve other important national problems in energy, bioscience, and theenvironment. Science & Technology Review is published ten times a year to communicate, to a broadaudience, the Laboratory's scientific and technological accomplishments in fulfilling its primary missions.The publication's goal is to help readers understand these accomplishments and appreciate their value tothe individual citizen, the nation, and the world.

Please address any correspondence (including name and address changes) to S&TR, Mail Stop L-664,Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94551, or telephone(510) 422-8961. Our electronic mail address is [email protected].

Prepared by LLNL under contractNo. W-7405-Eng-48

S&TR is available on the Internet athttp://www.llnl.gov/str. As references becomeavailable on the Internet, they will beinteractively linked to the footnote references atthe end of each article. If you desire moredetailed information about an article, click on anyreference that is in color at the end of the article,and you will connect automatically with thereference.

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Digital Mammography

SCIENTIFIC EDITOR

Ravi Upadhye

PUBLICATION EDITOR

Dean Wheatcraft

WRITERS

Arnie Heller, Ann Parker, Dale Sprouse, and Katie Walter

ART DIRECTOR

Ray Marazzi

DESIGNERS

Paul Harding, George Kitrinos, and Ray Marazzi

GRAPHIC ARTIST

Treva Carey

INTERNET DESIGNER

Kathryn Tinsley

COMPOSITOR

Louisa Cardoza

PROOFREADER

Al Miguel

S&TR is a Director’s Office publication,produced by the Technical InformationDepartment, under the direction of the Officeof Policy, Planning, and Special Studies.

2 The Laboratory in the News

3 Commentary by Wayne ShottsCountering Terrorism with Computers

Features4 Simulations to Save Time, Money, and Lives

For battle training or during preparations for a hostage rescue, on-screen conflict simulation programs save time and money—and may save lives.

12 The Secrets of Crystal GrowthLaboratory scientists have focused the power of the atomic-force microscope on revealing the secrets of crystal growth. Their findings are benefiting advanced lasers research as well as studies of the solution-based crystals of biological macromolecules.

Research Highlights21 Addressing a Cold War Legacy with a New Way to Produce TATB24 DNA Sequencing: The Next Step in the Search for Genes

27 Patents and Awards

Abstracts

S&TR Staff November 1996

LawrenceLivermoreNationalLaboratory

Printed in the United States of America

Available fromNational Technical Information ServiceU.S. Department of Commerce5285 Port Royal RoadSpringfield, Virginia 22161

UCRL-52000-96-11Distribution Category UC-700November 1996

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Science & Technology Review November 1996

N an increasingly complex post–Cold War world, thechallenge of countering terrorism against the public and

military stands side by side with the need to maintain thesecurity of thousands of nuclear weapons and fissile materialparts. To meet this challenge, Lawrence Livermore and othernational security laboratories are relying more and more ontheir computational power. Just as our nuclear weapondesigners have turned increasingly to computers to ensure thesafety and reliability of the nuclear stockpile, so our expertsin nonproliferation and arms control are investing incomputer simulation to respond to crises. Moreover, asdescribed in the article on conflict simulation beginning on p. 4 of this issue of Science & Technology Review, they areable to respond before the crises happen, thus creating a betterchance of prevention.

In fact, Livermore’s Conflict Simulation Laboratory isdeveloping a computer simulation to address an extremelyimportant preventable crisis related to stockpile security—aprogram to help prevent the theft of nuclear weapons fromU.S. or foreign stockpiles. Detailed simulations are being usedto train security forces to deal with potential terrorist attacks.

A key advantage of computer simulations is that theyprovide “mini-exercises.” Because they do not involve thetime-consuming and cumbersome deployment of troops andequipment in the field, they are a cost-effective way to assessa wide range of “what-if” scenarios. They can provide realismand, if necessary, allow a scenario to be dissected and thenrerun quickly to assess how different assumptions wouldaffect the result.

In dealing with nonproliferation and arms control for over 25 years, the Laboratory has assembled in theNonproliferation, Arms Control, and International Security(NAI) Directorate a broad range of programs to analyzeintelligence information, respond to emergencies, designsensors to monitor treaties, support international negotiations,

and evaluate weapon effects. These endeavors are allbenefiting from the computer revolution. Intelligence analystsare challenged to digest huge amounts of information to findthe elusive combination of evidence that would indicate asecret nuclear, biological, or chemical weapons projectsomewhere in the world. Emergency response experts have asimilar data-sifting challenge in working with law enforcementauthorities to separate real weapon-blackmail messages fromhoaxes. In designing instruments to monitor suspect facilitiesand to detect intruders at weapon storage sites, our sensordesigners are developing information systems with localprocessing to interpret simultaneous signals from nuclear,optical, magnetic, chemical, motion, and other sources; thesystem sends the analyses to a home base through globalcommunication networks. And, as described in this issue’sfeature article, computer simulation of a battlefield requiresnumerous types of military equipment and soldiers in real-world deployments with dozens of characteristics such aslocation, speed, and fighting capabilities, as well as quantifyinghow each element degrades during the course of the battle.

Almost all of the Laboratory’s directorates are involved inresponding to the nation’s new and highly complexnonproliferation and arms control challenges—countering bothnuclear smuggling and nuclear, biological, and chemicalweapon terrorism, while promoting international cooperationin protecting nuclear material. To perform these tasks in thefuture, Laboratory organizations will become increasinglyreliant on our growing computational power and expertise. Inparticular, NAI will rely on increasingly powerful andsophisticated computerized conflict and crisis simulations toprevent weapons proliferation and terrorism before theyhappen and to counter them when they do.

■ Wayne Shotts is Associate Director of the Nonproliferation, Arms Control, and International Security (NAI) Directorate.

Commentary by Wayne Shotts

I

Countering Terrorismwith Computers

2 The Laboratory in the News


Laboratory prepares for CTB implementationThe challenges of implementing the Comprehensive Test

Ban Treaty will require major contributions from LawrenceLivermore and other Department of Energy Defense Programfacilities, says Livermore Director Bruce Tarter.

In a statement following President Clinton’s signing of theCTB Treaty at the United Nations on September 24, Tarterpointed out that the Laboratory takes “very seriously theimportance of a successful Stockpile StewardshipManagement Program to make certain that the nation’snuclear deterrent is safe, secure, and reliable.” He also saidLawrence Livermore intends “to remain at the cutting edge in the enhancement of monitoring technologies in support of verification.”

Observing that the scientific challenges are considerable,Tarter said “they will require us to apply a very wide range oftechnical skills to sustained, difficult, large-scale tasksimportant to all Americans. This is the sort of national effortat which Livermore has always excelled, the kind of boldprogram that defines us as a Laboratory.”

Tarter noted that Lawrence Livermore personnel had spent“many thousands of hours”—at the Laboratory, inWashington, D.C., and in Geneva supporting efforts by theU.S. government to bring the CTB Treaty negotiations tocompletion. Said the Director: “Many key challenges duringthe negotiations were overcome with the help of experts andtechnologies from LLNL.”Contact: Jeff Garberson (510) 422-4599 ([email protected]).

Lab gets $6.2 million for environmental cleanup R&DThe Department of Energy awarded $6.2 million to the

Laboratory during the summer under DOE’s EnvironmentalManagement Science Program, designed for basic researchthat stimulates development of innovative environmentalcleanup technologies. The $6.2 million funds five separateLawrence Livermore projects:• $1.6 million goes to an effort to use accelerator massspectrometry to investigate the geochemical factors influencingthe migration of radioactive elements through the soil.• $1.3 million funds the development of computer codes forintegrating various geophysical data, such as seismic orelectromagnetic data, to produce as accurate a picture aspossible of underground contamination.• $1.2 million will be spent to develop techniques for trackingthe motion and chemistry of contaminants as they flowdownward to the watertable.• $1 million is earmarked for a companion project to theabove, aimed at developing electromagnetic imaging methodsto diagnose contaminants beneath the earth.

• $1.1 million funds a study of the mechanism of movementof toxic metals found underground.

Lab recipients of the DOE funds anticipate that theirprojects will spawn new environmental researchcollaborations with other national laboratories anduniversities, as well as expand existing collaborations.Contact: Jay Davis (510) 423-1414 ([email protected]).

Lab conference looks at peacekeeping technologyPolicymakers, United Nations military commanders, and

national laboratory scientists met at Lawrence Livermorerecently to explore how technology could aid internationalpeacekeeping operations. Of particular interest to militarycommanders and policymakers were mine removal, sensor,and antisniper technologies.

Titled “Meeting the Challenges of International PeaceOperations: Assessing the Contributions of Technology,” thetwo-day event in September was the inaugural conference forthe Laboratory’s Center for Global Security Research,established to better connect the Laboratory to the policycommunity.

Said Robert Andrews, the Laboratory’s former associatedirector for Nonproliferation, Arms Control, andInternational Security, who led the effort to create the center:“Peacekeeping forces are used for many different purposes.The Laboratory can play an important role because of thetechnology we have here.”Contact: Robert Andrews (510) 422-5006 ([email protected]).

Carrano elected VP of Human Genome OrganizationTony Carrano, the Laboratory’s associate director for

Biology and Biotechnology, has been elected vice presidentof the international Human Genome Organization (HUGO).As vice president, Carrano heads up America’s branch of theorganization, which represents North, Central, and SouthAmerica.

Internationally, HUGO represents nearly 1,000 membersfrom 50 countries who are involved in the global effort tomap and sequence all of the human DNA. Carrano, directorof the Laboratory’s Human Genome Center, is one of 18 members of HUGO’s international council.

The Laboratory has been involved in the Human GenomeProject since 1986. In 1991, it received official designation asa Human Genome Center. Lab researchers focused much oftheir early work on mapping chromosome 19, whichrepresents only 2% of the human DNA. Since early 1995,Lab researchers have broadened their scope to include theentire human genome. (See a related article beginning on p. 24 of this issue of S&TR.)Contact: Tony Carrano (510) 422-5698 ([email protected]).

(continued on page 28)

Simulations To Save Time, Money, and LivesSimulations to Save Time, Money, and Lives

NAUGURATION Day is fastapproaching, and the Secret Service

is planning the protection of thePresident. He will be taking the oath ofoffice, speaking before a huge crowd,and walking or riding down wide streetslined with people. Planning such anevent has always been a majorundertaking, but it is complicated todayby the growth of terrorist activities. TheSecret Service must make manydecisions—how large a security force touse, where individuals should belocated, where temporary fences orother barricades should be constructed,the likeliest sources of sniper fire andother attacks, and to which nearbybuildings should access be restricted.

In April 1996, the Secret Servicecontacted Lawrence Livermore NationalLaboratory’s Conflict SimulationLaboratory asking to use their JTS(Joint Tactical Simulation) system forinaugural planning. By portrayingvarious scenarios using JTS, the SecretService can watch each scenario unfoldon-screen and quickly analyze securitytactics and options, rehearse the event

so that there will be few surprises, andtrain its officers and other leaders toconduct the operation effectively.

JTS and other computerized conflictsimulation systems were originallydesigned for the military for battlefieldexercises. After these programs becamepopular, organizations responsible forsite security, disaster relief, and hostagerescues recognized their usefulness.More recently, state and localgovernments have become interested inusing simulations to plan police raids,drug interdictions, fire fighting, crowdcontrol, and prison riot control.

LLNL’s Pioneering WorkWell into the 1970s, the principal

tool for simulating battle andconducting “what-if” scenarios was the“sand table.” This was a large surfacedotted with tiny trees, rivers, and townswhere model tanks, soldiers, and otheraccoutrements of battle could bedeployed and moved about to simulatemilitary maneuvers. Sand was oftenused to form the terrain, hence the term.But sand tables were an imperfect wayto portray war games because they werean open system—both sides could seeeach other. Lines of sight weredetermined by running a piece of stringbetween two points, and decisions aboutthe outcome of a conflict were decidedby tossing dice.

Livermore’s involvement in combatsimulation was born in 1973 when

Laboratory scientists began studying thebattlefield utility of recently developedtactical nuclear weapons. They neededsomething better than a sand table tographically portray potential uses ofthese weapons and the ramifications oftheir use. Out of this need came Janus, atwo-sided, interactive, conflictsimulation program named for theRoman god of portals who had twofaces to look in two directions at once.Written in FORTRAN and running on16-bit computers, Janus was one of thefirst simulation programs to featureplayer input and output using aninteractive graphical user interface.Scientists and battle planners finally hada realistic, digitized battlefield map withmovable, changeable icons. (Forreference, Janus was developed at aboutthe time that “Pong,” the first interactivecomputer game, became popular.)

An early version of Janus wastransferred to the Army in 1983 whileLivermore continued to refine it. In themid-1980s, 32-bit microprocessors wereadopted and the design was modified tosupport asynchronous operations, amore flexible programming system thatallows a program to be interruptedand/or extended. Incorporating high-resolution graphics, distributedprocessing, and real-time play, Januscould be used for combat and tacticalprocesses from the squad to brigadelevel. In 1991, the Army took over fullresponsibility for Janus.

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Simulating a battle, hostage rescue—or Presidential inauguration—on-screenbefore it happens saves time and moneyand may save lives.

1974 to develop simulation programssuch as Janus. After Janus attracted theattention of the Army, the CSL wasasked by several other organizations toexpand upon Janus’s capabilities.

For the Department of Energy, theCSL developed a system to evaluate theeffectiveness of site security and to trainsecurity personnel. Over the nextseveral years, various iterations of thissystem, for the U.S. Air Force SecurityPolice Agency, the Berlin Brigade, andU.S. Army Europe, were created andultimately merged in the single systemknown today as the Joint TacticalSimulation (JTS) model, which is beingused by the Secret Service for inauguralplanning. JTS simulates conflict in bothurban and suburban environments andin building interiors.

JTS is constantly being updated toincorporate new features, and newversions of the system are released aboutevery six months. The latest release wasdelivered in September 1996.

JTS can be applied to a battalion-levelbattle as well as to the defense of anindividual building or site—in otherwords, JTS can be used to plan a largeengagement or the rescue of a singlehostage. The design is compatible withmodern conflict simulation standards,including the Distributed InteractiveSimulation protocol, that allowinteraction with other simulations,human instrumentation systems, and avariety of vehicle and aircraft simulators.

JTS is used today by military andDOE organizations for securityassessments of U.S. and NATO militarybases and DOE sites. It is also used bythe Army in Europe for large-scalecombat modeling and leadershiptraining. In advance of U.S.involvement in Somalia, the Army usedJTS to analyze terrain at the Mogadishu

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Conflict Simulation

On December 20, 1989, 20,000 U.S.troops invaded Panama and overthrewthe dictatorship of General ManuelNoriega. Prior to the invasion, the U.S.Army used Janus as an operationalplanning tool. During a full day ofsimulations, it became clear that theplanned placement of one platoon priorto the outbreak of hostilities caused adelay in arriving at a company’s firesupport position, so the platoon’sposition was changed. A later poll ofbattalion and company leaders revealedthat the war games may have savedlives during the invasion and ensuingbattle—a significant accomplishmentfor the first known use of acomputerized, interactive, force-on-force war game prior to an actualbattle.1

Why Use a Simulation?The experience with the Panama

invasion makes clear the benefit ofconflict simulations prior to a battle.But multisided, interactive simulationsallow fast, cost-effective planning,evaluation, and training for almost anyendeavor that involves multiplepersons or agencies working togetherfor a common goal. Simulations canassist with resource allocation andscheduling, coordination in andbetween agencies, managementdecision-making, procurementplanning, and tactics. Simulations of aconflict are also valuable tools forapprising staff and others of the currentsituation while the event is under way.Simulations of what actually occurredare also frequently used for after-the-fact analysis of an event.

For military training, simulations areparticularly useful now because militaryorganizations can afford fewer traininghours and smaller expenditures duringfield exercises. As the military movesinto nontraditional missions such aslarge-scale evacuations, peacekeeping,and famine relief, simulations help totrain military leaders without a largeinvestment.

These simulation programs are notintended to train individual soldiers orother participants in a conflict; rather,they train the mission leaders. Byparticipating in different scenarios,leaders learn how to respond to a widevariety of situations.

JTS Is State of the ArtLivermore’s Conflict Simulation

Laboratory (CSL) was established in

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Conflict Simulation

The sides in a two-sided“game” are generallyreferred to as the Red Teamand the Blue Team. Thisgame is taking place in thefacilities of the ConflictSimulation Laboratory atLawrence Livermore.

In the mid-1970s, aprogram developer atthe Conflict SimulationLaboratory runs anearly, very simpleconflict simulation.

An early version ofthe Janus simulationprogram from the late1970s used agraphics digitizerboard.

many as ten sides represented in theconflict simulation, each represented bya set of workstations networkedtogether. A conflict is usually thoughtof as having two sides, but civilians andother players may be treated as one ormore neutral sides.

The JTS system database storesextremely detailed information on everyfacet of a conflict—weapons, munitions,sensors, groups of soldiers, types ofmissions, observers, vehicles, securitysystems, and others. For example, thedatabase stores approximately 150pieces of data on a typical engineeringsquad, including the time it takes thesquad to get into and out of trucks, thetypes and numbers of weapons availableto the squad, and the time it takes thesquad to dig foxholes, penetrate wirebarriers and rubble, and perform otherengineering tasks. User organizationsconstruct this huge database, and theymay add and modify information asneeded.

For a particular simulation, itsplanners select appropriate people,weapons, vehicles, etc., from thisdatabase. For analysis of security at an

embassy, the numbers selected might berelatively small. Operational planningbefore the Panama invasion would haverequired the database to includethousands of soldiers in variousconfigurations, as well as large numbersand many types of weapons, munitions,vehicles, tanks, helicopters, planes, andthe like.

Before the start of a battle scenario,planners decide the parameters: theydecide the location, the weather, thelocal civilian situation, when and howthe battle will begin, and the makeup ofthe various sides; they select initialroutes and speeds for vehicles andpeople; they determine where, when,and what kind ofreinforcements will bedropped off. An almostinfinite number ofvariations are possible.Later, when the scenariois being played out, thesevariables may bechanged as requirementsdemand.

JTS allows for asimulation area as large

as 6 degrees of latitude and longitude, theequivalent of 660 by 660 kilometers. Anyuser may view the entire playing fieldduring a scenario, although each playercan only view forces that have beenacquired by the assets he or she controls.A high-level mission leader may chooseto view the entire playing field, while alower level player responsible formaneuvering specific forces will likelyzoom in for a more detailed view of asmaller area.

The workstation screens show suchfeatures as topography, vegetation,built-up areas, roads, rivers, oceandepths, building floor plans. Vegetationappears on the screen in various colors,

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Conflict Simulation

airport in order to select appropriateguard tower heights, identify the leastvulnerable areas for civilian shelters,optimize sniper placement, and find thesafest take-off and landing paths at theairport. In 1995, prior to our presentinvolvement in Bosnia, the Army usedJTS to run “what-if” scenarios forsending troops overland to Sarajevofrom the sea. They identified bottlenecksin the mountainous terrain and simulatedprobable ambush locations.

JTS is an entity-level simulation,which means that it explicitly models an individual howitzer, plane, ship, orsoldier. It can handle force sizes from 2 entities to 2,000.

JTS is one of the few programs tosimulate night and adverse weatheroperations, with area lights andspotlights that can be turned on and offas needs require. Terrain features suchas buildings, roads, rivers, fences, andvegetation can be modeled down to the

nearest 10 centimeters. Underwaterobstacles and river currents can also be modeled.

JTS is also rare in that it addressesdirect-fire fratricide, the killing offriendly forces by directly firing onthem, usually with small weapons.(This contrasts with indirect-firefratricide, which occurs when large-weapons fire is aimed at an area aboutwhich the shooter has minimalinformation. Many simulation modelsaddress indirect-fire fratricide.) Evenwith the best of information aboutwhere enemy and friendly forces arelocated, direct-fire fratricide doeshappen in the confusion of battle. But ithas traditionally been difficult to modelbecause of its sensitivity and lack ofavailable data. With JTS, the user mayestablish how and where direct-firefratricide might occur through asimulation.

Using JTSA JTS simulation session might

involve as few as 2 terminals or asmany as 40, each viewing a differentpart of a battlefield. There can be as

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Conflict Simulation

A strategic planning exercise in Central Americacoordinated by the U.S. Southern Commandinvolved soldiers from several countries. Theyare shown using the Joint Conflict Model (JCM)developed at Lawrence Livermore. (For moreinformation on JCM, see “Modern Technologyfor Advanced Military Training,” Energy &Technology Review, UCRL-52000-95-3 [March1995], pp. 22–24.)

A 10-square-kilometer view usingthe Joint Tactical Simulation(JTS), Livermore’s most recentcontribution to advanced conflictsimulation modeling.

Two views of an Air Force weapons storage facilityusing JTS. (a) A 1-square-kilometer view of theentire facility. Terrorists attacking the base areshown in red, and the blue figures are the defendingAir Force Security Police. (b) Kim Lohman workswith a view of just part of the facility showing lines ofsight for one of the terrorists.

(a)

(b)

http://www.llnl.gov/str/03.95.html

during part of the scenario and thendefect to another side. JCATS will beable to accommodate these fluidrelationships.

Military personnel will be able touse JCATS as a training tool whileworking at their own real-worldequipment rather than at a computerterminal. For example, simulation datawill be fed into shipboard equipment,and sailors and officers will respond toit as though it were the real thing.While JTS and other programs havebeen used in conjunction with vehicleand flight simulators, this use of asimulation program with realequipment will be a first.

Future Work for the CSLLivermore’s Conflict Simulation

Laboratory now has over 20 years ofexperience in developing and deployingsystems such as JTS and JCATS,working closely with the relevantbranches of the military during allphases of each project. Upon its releasenext year, JCATS will be thecornerstone of the Joint Chiefs ofStaff’s battalion, brigade, and lower-level training programs until the JointChiefs bring the Joint SimulationSystem (JSIMS) on line in 2003.Lawrence Livermore will likely be atechnical advisor for the development of JSIMS.

The CSL has already begun workingon additions to JCATS that will appearin later versions of the model. Inparticular, the CSL aims to fill a majorgap in modern conflict models, which isthat none accurately models the impactsof information warfare. The capabilityto handle information warfare attacks isa significant challenge becausecommunications and control systemsare currently implicit in simulationprograms and assumed to be perfect.This new modeling capability willinclude an interface with operationalcommand, control, computers,

communications, and intelligence (C4I)systems. Other changes will includeincreasing the size of simulatedscenarios and adding an ability todevelop a software architecture in thefuture to take advantage of newcomputer networking and computingtechnologies as they arise.

After its release, JCATS will be usedas a test bed for JSIMS concepts and willbe integrated into the JSIMS architecture.Through these activities, the CSL staffwill continue to stay in the forefront ofconflict simulation technology.

Key Words: conflict simulation, Janus,Joint Conflict and Tactical Simulation(JCATS), Joint Tactical Simulation (JTS).

Reference1. Evaluating the Use of Janus as an

Operational Planning Tool in OperationJust Cause, The Titan Corporation,Olympia, Washington, June 1991.(Subcontract B098749).

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Conflict Simulation

differentiated not by type but bypenetrability, visibility, and ease ofmovement, which are what matter to aperson or vehicle trying to movearound on the ground or to a planeflying overhead trying to see thosepeople and vehicles.

Lines of sight are constantly beingdetermined as soldiers and vehiclesmove on and over the terrain. As anaircraft or other vehicle moves overlong distances or comes into the area ofanother friendly player’s forces, itstactical control may be transferred fromone terminal to another. Intelligencereports pass back and forth betweenterminals by telephone or other real-world communications media as usersreport that an enemy tank unit hasappeared or that a company in their areais being fired upon.

In a small-scale simulation (of ahostage rescue, for example), the localemight be a city with low-rise and high-rise areas; an airport; a river; manynarrow, winding streets; and numerousbridges, in addition to an unfriendlycivilian population. During the scenario,a user might zoom in on a multistorybuilding and see individual soldiers andcivilians moving around inside it.

JCATS InnovationsThe Conflict Simulation Laboratory

is currently developing for the JointChiefs of Staff a new, more broadlyuseful simulation system known as theJoint Conflict and Tactical Simulation(JCATS). More detailed than JTS,JCATS increases the number of entitiesthat can be handled in a simulation from2,000 to 60,000. The first version ofJCATS is due to be released in 1997.

JCATS will incorporate a uniqueexperimental feature that allows a userto “aggregate” entities into a group tobe moved, viewed, and controlled asone icon and then “deaggregate” thegroup back to the entity level fordetailed operations. A user will thus be

able to manage a large number ofentities on the battlefield and play avery detailed, high-resolution game inspecific areas without high-endcomputers or large numbers of players.

This aggregation/deaggregationfeature will help to control the cost oftraining exercises, but it is requiring theCSL to meet a major challenge. When aunit has been aggregated to include avariety of unlike entities such asriflemen, scouts, tanks, trucks, and othervehicles, how does the unit behave? Theaggregated unit “inherits” somebehaviors from its component parts, butother behaviors change whenindividuals become part of a group. Forexample, the group moves at the speedof the slowest individual, and there islittle truly independent behavior in agroup. These and other changes inbehavior are being considered whendefining aggregated unit behavior.

JCATS simulations include morerealistic graphics, especially forvisualizing activity inside a multistorybuilding or on complex terrain. Userswill get a three-dimensional look atactivity inside a building withoutsignificantly slowing down computerprocessing.

JCATS will be the only entity-levelmodel to show detailed, high-resolutionamphibious operations and otheraspects of sea-coast warfare, aparticularly useful feature for the U.S.Marine Corps and the Navy.

Another unique feature will be theestablishment of a “matrix ofrelationships” among the variousplayers in a simulation. In a multisidedconflict, there can be friends, enemies,and neutral players. A group of“friends” may form a coalition andfunction as a single “side.” But at somepoint during a simulation, the coalitionmay break down, causing a formerfriend to become a neutral player oreven an enemy. There may also beguerrilla troops who are on one side

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Conflict Simulation

DIANA E. SACKETT joined the Laboratory as a computerscientist in 1975 after having received a B.S. in mathematicsfrom Occidental College in 1974 and an M.S. in mathematicsfrom Stanford in 1975. She has worked on a variety of scientificand engineering computing projects since coming to LawrenceLivermore. She is currently the Associate Division Leader forModeling and Simulation in D Division and is head of theConflict Simulation Laboratory.

For further information contact Diana Sackett (510) 422-1671([email protected]).

Several applications of theSecurity Exercise EvaluationSystem, a precursor to JTS, areshown: (a) an airport securityexercise, (b) a drug interdictiontraining exercise, and (c) aharbor protection exerciseinvolving both the Navy and theCoast Guard.

About the Scientist

Hal Brand uses theexperimental three-dimensional building editorfor the Conflict SimulationLaboratory’s newestprogram, the Joint Conflictand Tactical Simulation(JCATS). This program isunder development and duefor release in 1997.

(a)

(b)

(c)

HE crystallized forms of a world of materials—from viruses to

semiconductors—hold the secrets totheir shapes and functions. With theadvent of the powerful atomic-forcemicroscope (AFM), LawrenceLivermore researchers have begunelucidating the growth mechanisms andthree-dimensional structures of widelydifferent solution-based crystals on thenanometer (billionth-of-a-meter) scale.

The detailed images reveal, inunprecedented clarity, the complexworld of crystal growth, includingmechanisms never before seen or evenpostulated. The results portend a newgeneration of products, ranging fromlife-saving pharmaceuticals to newoptical materials.

Leading the Lawrence Livermoreeffort to unravel the mysteries of crystalgrowth are physicist James De Yoreo andhis crystal development team in theLaboratory’s Chemistry and MaterialsScience and Laser Programs Directorates.De Yoreo and his colleagues received anR&D 100 Award in 1994 for developinga process that produces very high qualityKDP (potassium dihydrogen phosphate)crystals for inertial confinement fusionlasers.1 Using this process, which isdramatically faster than traditionalmethods, they announced in May 1996that their process had, in only 27 days,produced a KDP crystal measuring44 centimeters across. Under standard

growing conditions, such anaccomplishment would have taken up to15 months.

In 1994, De Yoreo and his colleagueTerry Land began using one of the sevenAFMs on the Livermore site to explorethe growth mechanisms of crystals in away never before possible. “The AFMhas given us the opportunity to study atthe nanometer level the physics ofcrystal growth and how it is affected byimpurities, defects, and solutionconditions,” according to De Yoreo.(See the box, p. 14, for a description ofthe three-dimensional, atomic-levelresolving power of the AFM and thebox, p. 15, for a discussion of howcrystals grow.)

Research with the AFM is a vitalelement of LLNL’s longstandingcrystal growth and characterizationeffort, born out of the LaserPrograms’ requirement for large,ultrapure crystals grown from tinyseeds. This work is also part of amuch larger Laboratory program tocharacterize materials on theatomic level, recognized by severalR&D 100 Awards to LLNLresearchers in the area ofnanotechnology. This researchoffers significant potential payoffsto virtually every major program at Livermore.

Avenues of ResearchMuch of the crystal development

team’s AFM work has centered on theneed to better understand KDP crystalgrowth because of its direct impact onthe National Ignition Facility (NIF), aplanned laser facility essential for theDepartment of Energy’s StockpileStewardship and Management Program.High-power lasers like the Laboratory’sNova laser use KDP crystals for opticalswitching and frequency conversion ofthe initial infrared light to ultravioletlight. Some 600 plates of KDPapproximately 40 centimeters indiameter and 1 centimeter thick will beemployed in the forthcoming NIF.2

13Crystal Growth

Using the powerful atomic-force microscope, Laboratoryresearchers are discovering thecomplex growth mechanismsand three-dimensionalstructures of solution-basedcrystals. The results portend anew generation of products,ranging from life-savingpharmaceuticals to newmanmade materials.

T

TheSecretsof CrystalGrowth

TheSecretsof CrystalGrowth


The crystal team’s research has alsofocused on the growth of solution-basedcrystals of biological macromoleculessuch as proteins and viruses. Slowgrowth rates, large diameters, and greatcomplexity in composition, structure,and surface make biologicalmacromolecular crystals ideal systemsto study with the AFM. The teamreasoned that the images might revealentirely new growth mechanisms notseen in inorganic crystals.

An enhanced understanding ofcrystal growth of biologicalmacromolecules is likely to advancerational drug design, the technique ofusing powerful computers to literallydesign, in three dimensions, moleculesthat will precisely bind to key sites onproteins and enzymes to trigger or blocka biochemical action. Designing newdrugs in this fashion is dependent uponusing x-ray diffraction to reveal thethree-dimensional structure of complexmacromolecules. In this technique an x-ray beam is scattered by a crystal ofthe material of interest, a diffractionpattern is recorded, and the data aretransformed into a three-dimensionalstructure by computer.

However, this technique has beenlimited by problems encountered inobtaining high-quality crystals largeenough to yield precise structuralinformation. In fact, crystallization hasbecome the rate-limiting step in moststructure analyses because little isknown of the growth mechanisms of thecrystals and the orientation and bondingof the molecules in the crystallinelattice. Even less is understood aboutthe role of defects either as a promoteror a limiting factor in crystal growth.Using the AFM to study crystal growthis sure to improve the quality of x-raydiffractions and, hence, help hasten thearrival of new pharmaceuticals.

Biomineralization RevolutionIn a similar light, the knowledge

gained by the research team willadvance the understanding ofbiomineralization, a process used by awide variety of organisms from bacteriato humans to synthesize inorganiccomplexes such as bones, shells, teeth,and even magnetic material. Theseinorganic complexes are true“nanostructured” composite materialsand their physical properties are oftensuperior to manmade materials.

“Biomineralization researchrepresents a revolution in materials

15


Crystal Growth14


Crystal Growth

How the AFM Works

Lawrence Livermore researchers probing the dynamics of crystal growth use an atomic-force microscope (AFM), a recentdescendant of the scanning tunneling microscope (STM). Developed in 1981, the STM has become so important to materials scientiststhat its inventors were awarded the Nobel Prize in Physics in 1986. In 1987, a Lawrence Livermore–Lawrence Berkeley team used theSTM to create the first images ever produced of native DNA.*

Many researchers have turned to the AFM, an instrument ideally suited to imaging nonconductive samples such as crystals insolution. The AFM is similar to the STM in that both instruments use an extremely sharp tip to sense the atomic shape of a sample aswell as a computer to record the path of the tip and slowly build up a three-dimensional image. The only difference between the two isthat the STM electron tunneling tip is replaced by a mechanical tip, and the detection of the STM’s minute tunneling current is replacedby the detection of the minute deflection of the AFM’s cantilever.

In practice, the AFM tip is positioned at the end of an extremely thin cantilever beam and “touches” the sample with a force ofonly one ten-millionth of a gram, too weak to budge even one atom. As the tip is repelled or attracted to the sample surface, the cantilever beam deflects. A laser shining on the very end ofthe cantilever captures the magnitude of the deflection. The sample is oscillating left to right andfront to back, and a plot of the laser deflection versus sample position provides the resolution ofthe peaks and depressions that constitute the topography of the surface. Images take only 20 to30 seconds to complete.

Just as with a light microscope, researchers can vary the level of magnification of an STM orAFM image. The greater the movement of the sample, the larger the area being imaged. Thebroad magnifying range is shown below. Here a crystal of the plant protein canavalin is seen in itsentirety, then further enlarged to a 30- by 30-micrometer close-up of a growth mound, and thenenlarged still further to reveal its three-dimensional molecular lattice.

The AFM can be adapted to sense a range of forces including attractive or repulsive,interatomic, electrostatic, and magnetic forces. This ability allows the AFM to be used oninsulating surfaces and in liquids, feats the STM cannot do. Thus, the instrument is ideal forfollowing the dynamics of solution-based crystal growth.

* “Scanning Tunneling Microscopy: Opening a New Era of Materials Engineering,” Science & Technology Review, UCRL-52000-95-8 (August1995), pp. 4–11.

(a) The atomic-force microscope reveals, in ever-increasing magnification (b through d), the complexity of solution-based crystals.In (b) a canavalin protein crystal (within the yellow box) is shown on top of a hexagonal grid. (c) shows growth sources on thecrystal’s face. Each step is one molecule in height. In (d) the rhombohedral structure of the underlying lattice, outlined by the solidbox, defines the macroscopic rhombohedral form seen in (a).

How Crystals Grow—A Short Primer

Watching crystals grow with an atomic-force microscope reveals a frantic world ofmolecules continually bonding and dissolving, attaching occasionally to the surface ofa large crystal seed in one of many ways, and then perhaps joining together as part of agrowing structure of spiraling mounds, spreading layers, and small islands.

In the simplest form of crystal growth, molecules land on the surface of a growingseed and become weakly adsorbed. They may join together to form small, two-dimensional islands and spread outward in a layer (called a “step”) one molecule thick,with other islands forming and growing on top. In this dynamic growth process,molecules continually adsorb and dissolve from islands.

As the step edges advance, single molecules may diffuse from islands in thevicinity of the outer edge of a step or from solution and be “captured” by that edge. Inthis way the edge acts as a “sink” to diffusing molecules. It should be remembered,however, that molecules have complex shapes that prevent them from bonding inevery orientation. For example, a molecule may have to diffuse to the edge of a stepmany times until it has the correct orientation for incorporation.

Continuous spiraling steps are formed by screw dislocations, actual breaks in thecrystal’s structure often caused by impurities or from the applied stress of two blocksof crystals that meet up and do not match. Such “screw” dislocations create spiraling,multilayered mounds called vicinal hillocks.

Two other growth phenomena are easily seen with the AFM. The first, three-dimensional growth, consists of small clusters of molecules falling out of solution ontothe surface of a growing crystal face, meshing perfectly with the underlying structure.The second consists of the incorporation of sizable “microcrystals” that fall onto thegrowing crystal surface and create misaligned lattices.

In the dynamic world of crystal growth, all of the growth features described abovemay occur simultaneously. Which growth processes predominate are determined bythe size and shape of the molecule, the physical properties of the material,supersaturation levels, pH, the kind and quantities of impurities present in solution,and defects that may form in the crystal’s structure.

processing,” De Yoreo says.Understanding the process, however,again requires the ability to investigatecrystal growth at nanometer scale.

Most researchers have studied thegrowth of crystal surfaces by molecularbeam epitaxy or chemical vapordeposition, two processes used in theelectronics industry. However, theseprocesses are not representative of theliquid environments in which mostcrystals are grown. Such environmentsare characterized by varying levels ofsupersaturation (the driving force ofcrystal growth studies), where, because

(a)

(b) (c) (d)

0.8 by 0.8 millimeters 30 by 30 micrometers 300 by 300 nanometers


clusters containing 50 to 500 molecules.The most remarkable feature of this so-called three-dimensional growth is thatupon adsorption, the molecular clustersreorient so that the cluster latticemerges with the lattice of the largercrystal to which they adsorb, withoutcreating defects or discontinuities. Themultilayer islands in Figure 2 areexamples of such clusters.

At very high magnification, theimages show that the crystal surfacesupports a dynamic population of smallclusters (25 to 50 nanometer in diameter)of 7 to 30 canavalin molecules. Whilesome of the smaller clusters adsorb ontothe surface but then dissolve rapidly,others are stable and are incorporatedinto the advancing steps (or layers)formed by the dislocations.

At typical supersaturation levels usedin protein crystal growth, a new defectgeneration mechanism, never beforereported, was discovered: theincorporation of sizable “microcrystals”much larger than the clusters (Figure 3).When these microcrystals fall onto the

17


Crystal Growth

of increased temperature and pressure,most molecules are dissolved beyondthe saturation point and then permittedto precipitate out of solution onto theseed crystal.

Given the dearth of research in high-resolution, solution-based crystalgrowth, some basic questions need to beanswered: What are the dominantgrowth mechanisms and how do theyvary with different supersaturationlevels? What are the kinetic factors thatcontrol the rate at which crystals grow?And how do impurities and defectsaffect growth?

To answer those questions,De Yoreo and Land at Livermore andAlex Malkin and Yuri Kuznetsov from

the University of California atRiverside have been using AFMs toexamine in unprecedented detail thegrowth of crystals of the plant proteincanavalin, the satellite tobacco mosaicvirus (STMV), and KDP. Theirexperiments involve growing thecrystals under supersaturatedconditions until about 3 to 5 seedcrystals in a volume of 3 microliters areproduced. The crystals are thentransferred to the 50-microliter fluidcell of an AFM. As the crystals grow,supersaturation levels and pH arevaried and dozens of images recorded.

Prized Protein ImagesThe macromolecule canavalin, the

storage protein of the jack bean, waschosen for study because the UCRiverside collaborators know itsstructure well and can prepare very puresolutions of its crystallizable form. TheAFM images (Figure 1 and those on p. 12) show that at low supersaturatedlevels, the crystals grow by formation ofdislocations (formed by stress inside thecrystal lattice) and simple diffusion ofsingle canavalin molecules onto thegrowing spiral layers caused by thedislocations. (See the box on p. 15 for a general discussion of how crystalsgrow.) The dislocations producepolygonal spiral mounds called vicinalhillocks that appear in severalvariations: simple hillocks withindividual dislocation sources one ortwo layers high, complex ones withmany interacting dislocations, and left-or right-handed hillocks.

As supersaturation increases, two-dimensional growth sets in, seen in theappearance of small islands rising fromthe surface (Figure 2). At the highestsupersaturation levels, another growthsource, first discovered at Livermoreduring STMV studies, is seen: theadsorption of small, three-dimensional

16


Crystal Growth

Figure 2. Assupersaturationincreases, two-dimensional growth ofcanavalin crystalssets in, seen in theappearance of smallislands rising from thesurface.

Figure 3. At highsupersaturation levels,microcrystals fall onto thegrowing surface ofcanavalin crystals and areincorporated into the maincrystal, resulting inmisaligned and distortedlattices. Shown are (a) crystal beingincorporated and (b) defectremaining afterincorporation.

(a)

(b)

33 by 58 micrometers

8 by 8 micrometers 50 by 50 micrometers

27 by 27 micrometers

Figure 1. At lowsupersaturation levels,many crystals grow ondislocations (formed bystress inside the crystallattice) that producespiraling mounds calledvicinal hillocks. Vicinalhillocks on a crystal of KDP(potassium dihydrogenphosphate) are shown here.

dimensional islands. In addition,numerous two-dimensional islandsappear on the “terraces” (spacesbetween layers) formed by dislocations.As with canavalin, the dislocations arecaused by stresses in the crystal’s “stiff”lattice and produce growth hillockswhose triangular shapes reflect thecrystal symmetry (Figure 1). However,because the KDP lattice is much stiffer,the region near the dislocations ishighly stressed and unstable. As aresult, it exhibits hollow channels full ofsolution at the dislocation cores(Figure 5). These hollow cores (1 to50 nanometers in diameter) are a resultof stresses near the dislocations. Usingthe AFM to investigate the details of thedislocation structure has allowedLivermore researchers to show for thefirst time that core radii are one of theprimary determining factors in hillocksize and growth rate.

The diffusion and incorporationkinetics of single KDP molecules is1,000 times faster than seen incanavalin; indeed, typical KDP growthrates—about 100 molecular layers persecond—make it impossible to access awide range of experimental conditions.The crystal research team believes thatthe disparity in growth rates occurseither because KDP is much smallerand therefore more mobile thancanavalin or because KDP moleculeshave a higher probability of having theproper molecular orientation for directincorporation into the crystal, asopposed to more geometrically complexbiological macromolecules.

First-ever images also show howimpurities cause growing layers toexhibit discontinuous motion becausethey become “pinned.” In a dynamic,repeating process, steps encounterimpurities, seemingly stop, then growaround the impurities, and once againencounter other impurities. One seriesof images shows how an adsorbed

particle (impurity) is displaced upwardas growing steps move through it.

The Laboratory’s crystaldevelopment team plans additionalexperiments with various concentrationsof known impurities to furtherunderstand how they are incorporated inthe KDP crystal and how they influencegrowth. Such experiments are importantbecause despite dramatic gains ingrowth speed and quality, the number ofdefects in KDP crystals caused byimpurities is still unacceptably high forlaser scientists planning the opticalsystems of NIF. When an intense laserbeam strikes a defect in the KDP crystal,

19


Crystal Growth

growing crystal surface, they result inmisaligned and distorted lattices. Suchdefects should significantly impair theability of crystallographers to resolvemolecular structure through x-raydiffraction techniques.

Viruses Prove Good ModelsBecause of their relatively large size,

near-spherical shapes, and simplepacking geometries, viruses provideespecially good models for investigationof macromolecular crystallization. Theresearch team used an AFM to conductthe first nanometer-scale crystal growthstudy of STMV. The virus was chosenbecause past studies have determined itsstructure and have shown it to be easilycrystallized under a wide range ofconditions.

The AFM images reveal that thedominant growth mechanism at allsupersaturations for STMV crystals isthe continual adsorption of small, three-dimensional nuclei falling on thesurfaces of the growing crystals. Aswith canavalin, the nuclei integrate

remarkably well with the underlyingstructure. Livermore crystal researchersbelieve that this integration suggeststhat the underlying lattice either“guides” the adsorbing nuclei intopreferred orientations as they arrive orthat subsequent reorientation bydiffusion ultimately produces thecorrect alignment.

Once adsorbed, the three-dimensionalnuclei spread laterally and areaccompanied by the formation of two-dimensional islands on their tops. Theseislands coalesce in the formation of“stacks” consisting of a few to tens oflayers projected above the larger crystalsurface. Such stacks serve as the growthcenters for the entire crystal (Figure 4).

No screw dislocations are observedon STMV crystals during their growth.De Yoreo conjectures that nodislocations occur because, unlikeinorganic crystals, macromolecularcrystals are weakly bonded and aresufficiently “flexible” to accommodatevery high stress without sufferingbreaks in their internal structure.

KDP Studies Essential to NIFThe AFM studies reveal that KDP

crystal growth takes place on bothdislocation-induced steps and two-

18


Crystal Growth

Figure 4. (a) Once adsorbed,three-dimensional nuclei grow by(b) lateral spreading andformation of two-dimensionalislands on their faces. (c) Theseislands coalesce in the formationof “stacks” consisting of a few totens of layers projected above thelarger crystal surface.

All images are 15 by15 micrometers

Figure 5. Stresses in the KDP crystal’s “stiff”lattice produce growth hillocks with hollowchannels full of solution. The size of thechannel increases rapidly with the size ofthe dislocation from (a) one step where nocore is observable to (b) two, (c) three, and(d) four steps.

(a)

(a) (b)

(c) (d)

(b)

(c)

time = 0

time = 5 minutes

time = 18 minutes1.8 by 1.8 micrometers 2 by 2 micrometers

4 by 4 micrometers 1.8 by 1.8 micrometers

21

tiny cracks appear in the crystal thatgrow with each laser shot. Eventuallythe damage significantly disrupts thelaser beam quality by distorting the laserlight and reducing its energy.

Future areas of study also includegrowing several crystallized proteins,among them human insulin, whose usedepends on a better understanding ofhow they grow and dissolve in solution.The crystal development team is alsoplanning to study biomineralization inmore detail, in particular the growthcharacteristics of the essential calciumcarbonate mineral that forms theskeletal tissue of most organisms. Thestudy should shed light on how livingorganisms produce crystalline materials,thereby pointing the way for new,nanostructured materials for industry.

By understanding and thencontrolling the crystallization process atthe molecular level, complexmicrostructures can be synthesized thatwill affect many disciplines andtechnologies, says De Yoreo. “There’s arevolution on the horizon in materialsand materials processing, but to getthere we need to acquire the scientificunderpinnings of crystal growth,” hesays. Thanks to the AFM, that day israpidly approaching.

Key Words: atomic-force microscope(AFM), protein crystallography, crystals,KDP (potassium dihydrogen phosphate),National Ignition Facility (NIF), scanningtunneling microscope (STM), stockpilestewardship.

References1. “Growing High-Quality KDP Crystals

Quickly,” Energy & Technology Review,UCRL-52000-94-11 (November 1994),pp. 3–5.

2. The December 1994 issue of Energy &Technology Review, UCRL-52000-94-12, is dedicated to a complete descriptionof NIF and its planned uses.

20


Crystal Growth

For further information contact James De Yoreo (510) 423-4240([email protected]) or Terry Land (510) 423-5836([email protected]).

JAMES DE YOREO joined Lawrence Livermore NationalLaboratory in 1989 as a physicist in the Chemistry and MaterialsScience Directorate. He received his B.S. from Colby College andhis M.S. and Ph.D. from Cornell University. He is currently theleader of the Laboratory’s crystal development team and has doneextensive research in crystal growth physics and applications. In1994, he shared an R&D 100 Award for the development of a

rapid growth process for KDP (potassium dihydrogen phosphate) laser crystals withcolleagues at the Laboratory and at Moscow State University in Russia. He haswritten numerous articles on organic and inorganic crystal growth and is co-holderof one existing and one pending U.S. patent related to crystal growth.

About the Scientists

TERRY LAND received both her B.S. in chemistry (1988) and her Ph.D. in physical chemistry (1992) from the Universityof California, Irvine. She joined the Laboratory’s Chemistryand Materials Science Directorate in 1992. Her primary area of academic and professional research has been thefundamental growth mechanisms of solution-grown inorganicand macromolecular biological crystals using advanced

techniques such as scanning tunneling and atomic-force microscopy. She has co-written over 20 scholarly articles and has been a presenter and invited speaker atmeetings and conferences in the U.S. and Europe on the mechanisms andtechniques of crystal growth.

21


Addressing a ColdWar Legacy with aNew Way toProduce TATB

Research Highlights

Rob Schmidt (left), AlexMitchell, and Phil Pagoriadiscuss the chemistry of themethod for synthesizing TATB(triamino-trinitrobenzene)developed at Livermore. Theirmethod lowers the cost andproduction time of thisinsensitive high explosive andincreases the environmentalfriendliness of themanufacturing process. (Thereaction scheme on the boardappears also in the figure onp. 23.)

NE of the most important accomplishments made byweapons laboratories’ chemists in the past two decades

has been the formulation of powerful conventional highexplosives that are remarkably insensitive to hightemperatures, shock, and impact. These insensitive highexplosives (IHEs) significantly improve the safety andsurvivability of munitions, weapons, and personnel. TheDepartment of Energy’s most important IHE for use in

O

modern nuclear warheads is TATB (triamino-trinitrobenzene)because its resistance to heat and physical shock is greater thanthat of any other known material of comparable energy.

The Department of Energy currently maintains an estimatedfive-year supply of TATB for its Stockpile Stewardship andManagement Program (see the August 1996 Science &Technology Review, pp. 6–15), which is designed to ensure thesafety, security, and reliability of the U.S. nuclear stockpile.The Department of Defense is also studying the possible use ofTATB as an insensitive booster material, because even with itssafety characteristics, a given amount of that explosive hasmore power than an equivalent volume of TNT.

In addition to its military uses, TATB has been proposedfor use as a reagent in the manufacturing of components forliquid crystal computer displays. There is also interest inemploying the explosive in the civilian sector for deep oil wellexplorations where heat-insensitive explosives are required.

Despite its broad potential, the high cost of manufacturingTATB has limited its use. Several years ago, TATB producedon an industrial scale in the U.S. was priced at $90 to $250 perkilogram. Today it is available to customers outside DOE for




23TATBTATB22

Science & Technology Review November 1996 Science & Technology Review November 1996

The VNS process is more environmentally friendly than thecurrent synthesis. It employs mild reaction conditions andeliminates the need for chlorinated starting materials. The lattercharacteristic is especially important in light of the growingmovement to eliminate chlorinated compounds from theindustrial sector altogether because of their possible adverseenvironmental effects.

The VNS process depends on two key materials, TMHI(trimethylhydrazinium iodide) and picramide (trinitroaniline),which can be obtained from either inexpensive startingcompounds or surplus energetic materials available fromdemilitarization activities. TMHI can be prepared directly fromhydrazine and methyl iodide, or it can be synthesized byreacting UDMH with methyl iodide. Some 30,000 metric tonsof UDMH rocket propellant are located in the former SovietUnion, where they await disposal in a safe and environmentallyresponsible manner.

Two U.S. companies have received congressional fundingto demilitarize UDMH in Russia using a chemical process thatproduces lower value products (ammonia and dimethylamine).In contrast, the VNS process converts UVMH to TMHI, whichwill be used for the production of higher value products suchas TATB.

TMHI reacts with picramide in the presence of a strong baseto give TATB at a yield of over 95%. Picramide may beobtained from low-cost, domestically available nitroaniline.Or, as in the synthesis of TMHI, picramide may be synthesizedfrom a surplus munition, in this case, Explosive D. Severalmillion kilograms of Explosive D are available for disposal inthe U.S.

New Process to Increase TATB AvailabilityThe availability of relatively inexpensive TATB using the

improved synthesis will facilitate its use, both for military and

civilian applications. At the same time, the VNS processprovides a new avenue for disposing of large quantities ofenergetic materials that are a legacy of the Cold War. Theprocess reflects a new perspective within both the Departmentof Defense and the Department of Energy—treating surplusenergetic materials as assets to be recycled whenever possible.

This new approach to the synthesis of TATB and otherinsensitive energetic materials is still in the development stage.Over the next year, the synthesis will progress from the 10-gram scale at the Laboratory’s state-of-the-art HighExplosives Applications Facility to the kilogram-pilot-plantscale at Site 300. During this stage, the necessary performanceand sensitivity tests will be conducted to qualify the synthesisin terms of ease of use, purity, particle size, and cost. Theprocess will also be evaluated for environmental friendlinessand waste reduction. At the conclusion of the study, thetechnology will be ready for transfer to an industrial partner forcommercial scale-up.

Key Words: insensitive high explosives (IHE), stockpile stewardship,TATB (triamino-trinitrobenzene).

For further information contactPhil Pagoria (510) 423-0747([email protected]), Alexander Mitchell (510) 422-7994([email protected]), or Robert Schmidt (510) 423-6887([email protected]).

about $200 per kilogram. In response to a need for a moreeconomical product, chemists at Lawrence Livermore havedeveloped a flexible and convenient means of synthesizingTATB as well as DATB (diamino-trinitrobenzene), a closelyrelated but less well known IHE developed by the U.S. Navy.The initial phase of this work was funded by the Departmentof Defense (U.S. Navy) to explore the chemical conversion ofsurplus energetic materials to higher value products as analternative to detonation.

The Lawrence Livermore process—also called the VNS(vicarious nucleophilic substitution) process—should be ableto produce TATB for less than $90 a kilogram on an industrialscale in about 40% less manufacturing time. The process alsooffers significant advantages over the current method ofsynthesis in environmental friendliness, for example, byavoiding chlorinated starting materials. What’s more, theprocess uses either inexpensive, commercially availablechemicals or surplus energetic materials from both the formerSoviet Union (UDMH, a rocket propellant) and the U.S.(Explosive D, a high explosive).

By using UDMH (uns-dimethylhydrazine) and Explosive D (ammonium picrate), this process disposes ofenergetic materials left over as a legacy of the Cold War in anenvironmentally responsible manner. It allows the use ofsurplus energetic materials as unique feedstocks to makemore valuable materials such as higher value explosives orother products. Indeed, the new chemistry is also applicableto the synthesis of chemicals that are important intermediatesin the preparation of numerous pharmaceutical andagricultural chemicals.

Current Process Produces ImpuritiesThe currently accepted method for manufacturing TATB

in the U.S. involves a reaction sequence that starts with therelatively expensive and domestically unavailablechlorinated compound TCB (trichlorobenzene). Elevatedtemperatures of 150°C are required for two of the reactionsteps leading to TATB. The major impurity produced isammonium chloride; in addition there are low levels ofchlorinated reaction side-products.

Fran Foltz examines crystals of TATB(triamino-trinitrobenzene) under amicroscope. The background photographshows TATB crystals at high magnification.

The process of synthesizingTATB (triamino-trinitrobenzene)from picramide using TMHI(trimethylhydrazinium iodide)as expressed in this reactionscheme may result in a largedecrease in the cost of TATB.

KNO3

NO2

NH2

H2SO4

O2N O2NNO2 NO2

NH2

NH2H2N

NH2

NO2 NO2

4-Nitroaniline Picramide TATB

TMHI

DMSO NaOMe

(a) Chromosome

Coiled DNA

(b) DNA double helix

Sugar–phosphatebackbone of DNA

(c) The four bases

Adenine

Cytosine

Thymine

Guanine

25DNA Sequencing

Most facilities only sequence in 300-bp chunks. TheLaboratory’s Genome Center currently sequences about 700 to800 bp along the DNA. “We’re entering the era of productionsequencing,” said Lamerdin. “A lot of the up-front work hasbeen automated. There’s no more manual pipetting, forinstance. We have robots to do that.” (See the photo below.)

To sequence a section of DNA, researchers first use specialenzymes that act as biological “scissors” to cut DNA atspecific points into smaller fragments. They then clone ormake hundreds of identical copies of these fragments. Whenresearchers wish to sequence a fragment, they run four nearlyidentical reactions using that DNA as a template,in which the four bases are chemically labeledwith four different fluorescent dyes.

A laser scans thereaction products,exciting thefluorochromes,and a computercaptures andstores theresulting

fluorescent signals. (See the photo on p. 26.) Softwareautomatically determines the order of bases from the four-colordata. The Center has 13 of these sequencing machines, eachcapable of reading more than 25,000 bases a day. Additionalsoftware actually hunts for particular A, G, C, and Tcombinations that mark the beginnings and endings of genes.

24Research Highlights


DNA, so we’re estimating as many as 2,000 genes,” saidAshworth. “We have a handle on about 400, so there are a lotleft to find.” (See the box, next page.)

High Technology to the RescueWhat has made it possible to even contemplate sequencing

the entire genome are advances in genetic-engineeringtechnologies in the past decade.

Not so long ago, sequencing 40,000 bp was considered aworthy multiyear thesis project for a Ph.D. student. Livermore’sCenter now sequences this amount in less than a week using theCenter’s integrated system that sequences and tracks the DNAfragments being studied.

The best of current technology allows researchers tosequence about 1,000 bp along a stretch of a piece of DNA.

Research Highlights

The basics of genetics. Each cell in the human body (except red bloodcells) contains 23 pairs of chromosomes. Chromosomes are inherited:each parent contributes one chromosome per pair to their children. (a) Each chromosome is made up of a tightly coiled strand of DNA. Thecurrent research lies in the details of the DNA structure, which, in itsuncoiled state reveals (b) the familiar “double helix” shape. If wepicture DNA as a twisted ladder, the sides, made of sugar andphosphate molecules, are connected by (c) rungs made of chemicalscalled “bases.” DNA has four bases—adenine (A), thymine (T),guanine (G), and cytosine (C)—that form interlocking pairs. The orderof the bases along the length of the ladder is called the DNA sequence.The hunt for genes is focused on reading the order of the bases foreach DNA strand and determining which parts of the sequenceconstitute genes.

The difference between weapons testing and gene huntingmay seem enormous, but their connection relates to how thestudy of biology became an integral part of the Laboratory’swork. Livermore’s first biomedical program was chartered in1963 to study the radiation dose to humans of isotopes in theenvironment; a natural extension was to explore how radiationand chemicals interact with human genetic material to producecancers, mutations, and other adverse biological effects.

In the last 20 years, advances in microbiology, biochemistry,genetics, and bioengineering gave rise to the field ofbiotechnology. Recent advances in genetic-engineeringtechnologies then made it possible to examine and sequenceDNA faster and more efficiently than ever imagined. TheLaboratory was well positioned to take advantage of this newfield, which combines the disciplines of biology, genetics,engineering, and computer science. Pulling from otherLaboratory organizations, the Biology and BiotechnologyResearch Program called on engineers, physicists, and computerscientists to join biologists to help solve the mystery of thehuman genome.

In 1987, researchers at Lawrence Livermore began studyingall of chromosome 19. This project grew out of research on threegenes, each involved in the repair of DNA damaged by radiationor chemicals. As the Laboratory became known worldwide forits work on this chromosome, other researchers, hunting forgenes thought to be somewhere on this chromosome, contactedthe Laboratory and international collaborations were formed.Such collaborations discovered, for example, the genes formyotonic dystrophy (a late-onset genetic disease causing muscleatrophy) and a form of dwarfism called pseudoachondroplasia.

In 1990, the Department of Energy and the National Institutesof Health formed the joint Human Genome Project. The long-term goal of this 15-year project is to decipher the DNA of theentire human genome. Three DOE national laboratories—Lawrence Livermore, Los Alamos, and Lawrence Berkeley—areDOE centers for this project, while NIH supports eight facilitiesinvolved in this work.

Genes at LivermoreDNA SequencingThe Next Step in theSearch for Genes

OR Lawrence Livermore researchers involved in theHuman Genome Project, gene hunting is like standing in

front of a mountain, shovel in hand, and knowing somewhere,amongst tons of rock, is the motherlode.

The search has been going on for years, but it hasaccelerated recently to a new level, noted Linda Ashworth, aLawrence Livermore biomedical scientist working in theLaboratory’s Human Genome Center. “In 1992, about 80% ofour effort was devoted to generating road maps for specificchromosomes or regions on a chromosome.1 Now, about 70%of our effort goes towards sequencing DNA and furtheringsequencing technology.”

Sequencing involves determining the exact order of theindividual chemical building blocks, or bases, that form DNA.The four chemical bases—commonly abbreviated as A, G, C,and T—bind together to create base pairs that are the “businessend” of the DNA molecule. (See figure at right.)

After researchers sequence a piece of DNA, they search forthe special strings of sequence that form genes. The ultimategoal of the worldwide Human Genome Project is to find all thegenes in the DNA sequence and develop tools for using thisinformation in the study of human biology and medicine.Major benefits will be a better understanding of and treatmentsfor genetic diseases.

To the HuntIt is a hunt of gigantic magnitude, a bit like chopping away

at Mount Everest with a pick and shovel. Genes range in sizefrom 1,000 base pairs (bp) to over 1,000,000 bp. The smallesthuman chromosome (21) contains approximately 45 millionbp; the largest (chromosome 1) has approximately 250 million.The entire human genome contains about 3 billion bp. As ofmid-August 1996, about half of one percent of the humangenome had been sequenced worldwide in 15,000 bp chunks orlonger. “Maybe six times that amount has been sequenced insmaller pieces, which are useful for diagnostic purposes,”according to Jane Lamerdin, one of the Center’s researchers.

To put things in perspective, there are perhaps100,000 human genes scattered throughout the chromosomes,interspersed with non-gene material. “Chromosome 19, the onewe’re focusing on here at Livermore, has about 2% of the total

F

Manual pipetting is a time-consuming task of the past,thanks to automated workstationslike the one pictured at the leftwith biomedical scientist MariaDe Guzman. Before thesemachines were available, it tookone person all day to process 48 DNA samples for sequencing.Using the Genome Center’s threeworkstations, one person cannow process up to 1,000 samplesa day.

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A relational database, developed by Lawrence Livermorecomputer scientists, keeps track of where each clone is, whathas been done to it, who did it, when they did it, and what hasyet to be done. “When the sequencing was someone’s thesisproject, the individual usually kept track of progress in anotebook,” explained Lamerdin. “But in this kind of high-throughput environment, we need computers to track theprogress of all these pieces and also to help us makedecisions. Computational support is a critical element in thesuccess of this project.”

After SequencingDetermining the human genome sequence and finding the

genes is really just a first step. “Knowing the bases that makeup a gene and where it’s located on a chromosome doesn’ttell you what the gene does,” noted Ashworth. “Aftersequencing, we still need to determine what proteins thegenes produce, and what those proteins do in the cell.”

Why bother? First and foremost, genes and their proteinshold the key to unlocking the mysteries of inherited diseases.Once the genetic code for a disease is broken, gene and drugtherapies can follow. For example, the gene for cystic fibrosiswas discovered four years ago, and while we are still a longway off from “fixing” the gene defect that causes this disease,unraveling the gene’s secrets has allowed private industry todeal with one of the major symptoms of cystic fibrosis.

“So, the sequence is really a starting point,” saidAshworth. “We still need to know the structure and functionof the protein produced by the gene, and how that proteininteracts in the environment of the cell. The sequence, you

might say, is the detailed map we need to help us find theburied treasure.”

Future S&TR highlights will discuss the Center’s work onthe next-generation sequencing machine and a collaboration touncover the gene involved in one form of inherited kidneydisease.

Key Words: chromosome, DNA sequencing, gene, Human GenomeProject.

Reference1. “The Human Genome Project,” Energy & Technology Review,

UCRL-52000-92-4/5 (April/May 1992), pp. 29–62.

For further information contact Linda Ashworth(510) 422-5665 ([email protected]).The Human Genome Center’s Internet homepage is available athttp://www.llnl.gov/bbrp/genome/genome.html.The Department of Energy’s “Primer onMolecular Genetics” is available on the Internetat http://www.gdb.org/Dan/DOE/intro.html.

Livermore’s Human Genome Center has 13 sequencing machines,each capable of reading more than 25,000 bases a day. This imageshows one form of their output, where each color in the vertical bandsor “sequencing ladders” corresponds to one of the four DNA bases.Using the following translator, blue = C; green = A; yellow = G; red = T,you can trace a sequence ladder vertically and read a small portion ofthe genetic code.

DNA Sequencing 27Each month in this space we report on the patents issued to and/orthe awards received by Laboratory employees. Our goal is toshowcase the distinguished scientific and technical achievements ofour employees as well as to indicate the scale and scope of thework done at the Laboratory.

Patents and Awards

Patent issued to

John W. ElmerDennis W. O'Brien

Mark BowersAllen Hankla

Craig J. RiversRoanne A. LeeGlenn E. Jones

Troy W. Barbee, Jr.Timothy Weihs

Chi Y. Fu

Patent title, number, and date of issue

Electron Beam Machining Using Rotating and Shaped Beam Power Distribution

U.S. Patent 5,534,677July 9, 1996

Phase and Birefringence AberrationCorrection

U.S. Patent 5,535,049July 9, 1996

Electrically Shielded Enclosure withMagnetically Retained Removable Cover

U.S. Patent 5,534,663July 9, 1996

Ignitable Heterogeneous Stratified Structurefor the Propagation of an Internal ExothermicChemical Reaction along an ExpandingWavefront and Method of Making Same

U.S. Patent 5,538,795July 23, 1996

Process for Forming Synapses in NeuralNetworks and Resistor Therefor

U.S. Patent 5,538,915July 23, 1996

Summary of disclosure

An apparatus and method for electron beam (EB) machining (drilling,cutting, and welding) that uses conventional EB guns, power supplies,and welding machine technology without the need for fast bias pulsingtechnology. A magnetic lensing (EB optics) system and electroniccontrols are used to concurrently bend, focus, shape, scan, and rotatethe beam to protect the EB gun, to create a desired effective power-density distribution, and to rotate or scan this shaped beam in acontrolled way.

A four-wave mixing phase conjugate mirror that corrects phaseaberrations of a coherent electromagnetic beam and birefringenceinduced upon that beam. The stimulated Brillouin scattering phaseconjugation technique is augmented to include Brillouin-enhanced four-wave mixing. A seed beam is generated by a main oscillator that arrivesat the phase conjugate cell before the signal beams in order to initiatethe Brillouin effect. The signal beam being amplified through the amplifierchain is split into two perpendicularly polarized beams.

An enclosure having electrical components and an easily removableshielded cover with magnetic securement means to secure the cover tothe enclosure in a manner that provides an electrical seal between thecover and the enclosure to prevent the passage of electromagneticradiation through the joint between the cover and the enclosure. Themagnetic securement means are provided on the surface of theenclosure surrounding the opening and facing the cover, andferromagnetic means are provided on the surface of the cover facing themagnetic securement means.

A multilayer structure with a selectable propagating reaction frontvelocity (V), a reaction initiation temperature attained by application ofexternal energy, and an amount of energy delivered by a reaction ofalternating unreacted layers of the multilayer structure. Because V isselectable and controllable, a variety of different applications for themultilayer structures are possible, including their use as ignitors, injoining applications, in fabrication of new materials, as smart materials,and in medical applications and devices.

A customizable neural network where one or more resistors form eachsynapse. All the resistors in the synaptic array are identical, thussimplifying the processing issues. Doped, amorphous silicon is used asthe resistor material to create extremely high resistances occupying verysmall spaces. Connected in series with each resistor in the array is atleast one severable conductor whose uppermost layer has a lowerreflectivity of laser energy than typical metal conductors at a desiredlaser wavelength.

Patents

AwardsJames “Buddy” Swingle recently received the IntelligenceCommunity Seal Medallion from Central Intelligence AgencyDirector John Deutch during a ceremony at CIA headquarters inLangley, Virginia. Swingle, who is executive secretary and actingchairman of the Joint Atomic Energy Intelligence Committee, wascited for his “sustained superior performance” in producing foreignnuclear intelligence reports that “provided significant assistance tothe intelligence and policy communities.” Swingle has been atLivermore since 1972, working on a variety of high-energy laser andnuclear weapons programs. He joined the Nonproliferation, ArmsControl, and International Security Directorate in 1990 and wasrecently named leader of Z Division.

Lawrence Livermore’s Storm Water Management Program hasreceived the U.S. Environmental Protection Agency’s 1996 NationalStorm Water Control Program Excellence Award in the industrial

category. The award recognizes the Laboratory’s efforts to curb waterpollution through improved storm water control. Representatives fromthe Storm Water Management Program, a part of the EnvironmentalProtection Department in the Laboratory’s Plant OperationsDirectorate traveled to Dallas, Texas, in early October to receive theaward at the Annual Water Environment Federation Conference.

Three teams of Laboratory employees are recipients of HammerAwards for the Department of Energy. They are: the Life Cycle AssetManagement (LCAM) team from the Plant Engineering Department, apart of the Plant Operations Directorate; the DirectivesReengineering Group, out of the Office of Scientific and TechnicalInformation in the Director’s Office; and the PerformanceManagement Team, working out of the Office of Policy, also in theDirector’s Office. The Hammer Awards were created by Vice PresidentAl Gore to recognize special achievements in the efforts to reinventgovernment by improving customer service, cutting red tape,empowering employees, or getting back to basics.

http://www.llnl.gov/bbrp/genome/gemone.html

http://www.gdb.org/Dan/DOE/intro.html

Simulations to Save Time, Money, andLives

The Laboratory’s Conflict Simulation Laboratory (CSL)has been developing computerized programs to simulatecombat and other conflicts since 1974. All branches of themilitary use these systems for training purposes and toprepare for operations as diverse as the 1989 invasion ofPanama and peacekeeping in Somalia. The CSL is presentlycontinuing development of the Joint Tactical Simulation(JTS) and recently began work on the Joint Conflict andTactical Simulation (JCATS) program for the Joint Chiefs ofStaff. The Army is still using the CSL’s first model, Janus. ■ Contact: Diana Sackett (510) 422-1671 ([email protected]).

The Secrets of Crystal Growth

Lawrence Livermore researchers are using the atomic-force microscope (AFM) to elucidate the growth mechanismsand three-dimensional structures of widely different solution-based crystals on the nanometer (billionth-of-a-meter) scale.Much of the AFM work has been in support of the LaserPrograms’ need to better understand KDP (potassiumdihydrogen phosphate) crystal growth because of its directimpact on advanced lasers such as the National IgnitionFacility. A second avenue of research has focused on thegrowth of solution-based crystals of biologicalmacromolecules, specifically the protein canavalin and thesatellite tobacco mosaic virus. The AFM images haverevealed how solution-based crystals grow and how they areaffected by impurities, defects, and solution conditions. Theresults are likely to affect many disciplines and technologies,from pharmaceuticals to materials synthesis.■ Contact: James De Yoreo (510) 423-4240 ([email protected]) or Terry Land (510) 423-5836 ([email protected])

Abstracts

© 1996. The Regents of the University of California. All rights reserved. This document has been authored by the The Regents of the University of California under Contract No. W-7405-Eng-48 with the U.S. Government. To request permission to use any material contained in this document, please submit your request in writing to the Technical Information Department,Publication Services Group, Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94551, or to our electronic mail address [email protected].

This document was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor the University of Californianor any of their employees makes any warranty, expressed or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information,apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service bytrade name, trademark, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or theUniversity of California. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or the University of California andshall not be used for advertising or product endorsement purposes.

U.S. Government Printing Office: 1996/683-074-

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Researchers discover ice that resists meltingWhile performing studies of methane clatrate, a material

viewed as a potential energy source, scientists produced amysterious phenomenon—ice that does not liquefy whenheated well beyond its usual melting temperature.The energystored in methane clathrate deposits on Earth has beenestimated at twice that in all conventional hydrocarbondeposits of oil, gas, and coal.

The discovery occurred while researchers—Bill Durham ofLawrence Livermore and Laura Stern and Stephen Kirby ofthe U.S. Geological Survey—were experimenting with a newmethod for synthesizing methane clathrate, a solid compoundof water and methane occurring on Earth and possibly on theicy moons of the outer solar system. Clathrate refers to thecompound’s porous lattice–work structure.

In a project funded by NASA, the team mixed fine,granular ice and cold, pressurized methane gas in a constant-volume reaction vessel that was slowly heated under strictlyregulated conditions. Curiously, the scientists found that theice did not liquefy as predicted when the melting temperaturewas reached and surpassed. Clathrate was formed only aftermany hours, with the temperatures inside the reaction vesselreaching above 50˚F before the last of the ice was consumed(the researchers never did see melting) as part of the process.

The three scientists concluded that a kind of “chemicalarmoring effect” accompanying clathrate formationsuppresses the melting of the ice. They are hopeful that theirnew method of producing methane clathrates will pave theway for further experimentation and a better understanding ofthis phenomenon. Their findings were published in theSeptember 27 issue of Science magazine.Contact: Bill Durham (510) 422-7046 ([email protected]).

Lab-IBM making progress with new supercomputer Lawrence Livermore and IBM are moving ahead on a

$93 million project to build the world’s fastestsupercomputer. The production model of the 3-trillion-calculations-per-second supercomputer is scheduled fordemonstration in December 1998.

In September, Lawrence Livermore took delivery fromIBM of the first 512 processors, which make up two separatesystems that operate at 136 billion calculations per second,contain 67 billion bytes of memory, and include 2.5 trillionbytes of storage.

The supercomputer is based on the IBM RS/6000 SP*line of processors that allows a building block approach tohigh-performance computing with clusters of shared-memory processors. Although the 512 processors are farfewer than the 4,096 that eventually will make up theproduction model, they possess computing power more thanall that previously delivered to the Laboratory in its 45-yearhistory, according to Mark Seager, who led the Livermoreacquisition team.

The supercomputer is being installed as part of theDepartment of Energy’s Accelerated Strategic ComputingInitiative (ASCI), a ten-year, $1 billion program designed toeventually deliver 100-trillion-calculations-per-secondcomputing capability. The award of Blue–Pacific—as theLivermore machine is known—was announced by PresidentClinton at a White House event on July 26.Contact: Mark Seager (510) 423-3141 ([email protected]).

Magmatic CO2 may be key to volcano vitalityWhat is a volcano’s potential for eruption? Two

Lawrence Livermore researchers believe work theyperformed in the Cascade Volcanic Range in northernCalifornia and Oregon may point to a new method fordetermining how vital or dormant a volcano is.

Timothy Rose and M. Lee Davisson say the relativeamount of magmatic carbon dioxide observed at differentvolcanoes may someday provide a means of monitoring avolcano’s level of activity. Their work is discussed in apaper published in the September 6, 1996, issue of Science.

In a study to assess the presence of magmatic carbondioxide from volcanoes, the pair measured carbon-14 ingroundwater samples from 40 different springs and creekslocated in the Cascade Range. The absence of carbon-14 inthe water samples is an indicator that magmatic carbondioxide came from deep within the earth. (Because it has ahalf-life of over 5,000 years, carbon-14 is used as a meansof determining the age of objects.)

“There’s no question it’s a substantial leap fromidentifying carbon isotope tracers in groundwater to actuallycalibrating the amounts of gas to determine the degree ofdanger a volcano poses,” said Rose. “But it’s an intriguingphenomenon and worth further investigation.”Contact: Timothy Rose (510) 422-6611 ([email protected]) or M. Lee Davisson (510) 423-5993 ([email protected]).

The Laboratory in the News

*IBM trademark

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