neutron beam instruments and national deuteration … · neutron beam instruments and national...

Neutron beam instruments andNational Deuteration Facility

3Australian Nuclear Science and Technology Organisation

The Australian Nuclear Science and Technology Organisation (ANSTO) is the home of Australia’s nuclearscience expertise. This unique expertise is applied to neutron research, radiopharmaceutical production andresearch, climate change research, water resource management, materials engineering and a range of otherscientific research disciplines.

ANSTO is a Federal Government agency and operates a range of nuclear and non-nuclear facilities andequipment for research and commercial purposes including Australia’s only operating nuclear reactor, OPAL.

ANSTO’s Bragg Institute operates a suite of seven neutron scattering instruments using neutron beamsgenerated by OPAL. These instruments offer state-of-the-art performance, in many cases the equivalent ofinstruments on spallation neutron sources and much larger reactors, due to a combination of the latest opticsand detectors.

The neutron-beam instruments are used for solving complex research and industrial problems in manyimportant fields

� Platypus – a reflectometer

� Quokka – a small-angle neutron scattering instrument

� Echidna – a high-resolution powder diffractometer

� Wombat – one of the most powerful powder diffractometers in the world

� Kowari – a residual-stress diffractometer

� Koala – a laue diffractometer

� Taipan – a thermal triple-axis spectrometer.

The Bragg Institute is also home to the NCRIS-funded National Deuteration Facility (NDF) that offers thefacilities, staff and expertise to produce a wide variety of deuterated compounds for downstream analysissuch as small angle neutron scattering (SANS), neutron reflectometry, neutron crystallography and Nuclearmagnetic resonance (NMR).

This brochure provides information on ANSTO’s seven neutron beam instruments and the NationalDeuteration Facility.

Neutron beam instruments and National Deuteration Facility

Platypus

4 Neutron beam instruments and National Deuteration Facility

PlatypusTime-of-flight neutron reflectometer

Platypus is a leading-edge neutron reflectometerwith the added ability of studying films at the air-liquid interface (free-liquid surfaces). Neutronreflectometry is used to study surfaces, thin films,buried interfaces, magnetic films, multi-layeredstructures and processes that occur at surfaces and interfaces.

What makes Platypus special?

Neutron reflectometry provides information on thecomposition, changes in surface characteristics overtime, thickness and interfacial roughness of thinfilms with the precision of a few atoms.

Applications:

Neutron reflectrometry can be used to:

� Study of soft matter in biological and chemical science:

- Examining how surfactants work (substancesthat affect surface characteristics) eg:waterproofers, emulsifiers, lung surfactants inpremature infants

- The interactions of proteins and enzymes withbiomimetic cell membranes (syntheticmembranes used to model those in living cells)

� Deliver critical information about polymer filmcomposition, chemical properties and the qualityof the film in conjunction with other surfacesensitive techniques.

- Nanoscale plasma polymer surface coatings arekey elements used in the development of newbiotechnologies for, tissue growth,biofunctionalisation, surface passivation andanti-biofouling, protein and antibody biosensors.

� Study processes occurring at surfaces andinterfaces such as adsorption, corrosion,adhesion and inter-diffusion between layers tosolve important industrial problems

� Study prototypes of thin film magnetic devices to be used in future generations of computers,including magnetoresistive read head sensorsand data storage films in hard drives as well asnon- volatile magnetic random access memory devices.

Relevant fields include: Biology, chemistry, surfaceengineering, magnetic memory.

‘Chopper’ system –chops the neutron beams into pulsesso that their speed can be measured

Collimation tank –supermirror guides deflect the neutrons towards the samples

Detector tank –vacuum-sealed toreduce neutron losses

Detector –detects scatteredneutrons for analysis

Sample station –where samples are hit by neutrons, causing them to scatter

Split system –directs the neutron beam onto the sample at a precise angle

Neutron guide

Neutron beam



Case Study 1: Body repair and regeneration

Neutron reflectometry is helping ANSTO andresearchers at the University Sydney unravel themolecular structure of the mysterious proteinbuilding block of elastin: (tropoelastin).

Elastin is a critical component of elastic tissuespresent in the aorta, ligaments, major bloodvessels, lungs, skin and tendons.

It is present in all vertebrates. Synthetic elastinbiopolymers are currently finding uses in areassuch as the promotion of elastin regeneration,tissue engineering and medical implants.

Case Study 2: Biochemistry of cell membranes

Neutron reflectometry provides unique structuralinformation about cell membranes and how theyinteract with proteins, drugs and toxins. Forexample, the enzyme phospholipase-A2 (PLA2)plays a variety of roles from immune response inhuman cell membranes to being the activeingredient in many snake and insect venoms,including cobra venom.

Neutron reflectometry has been used to study themechanism by which PLA2 interacts withphospholipid molecules, which are the majorconstituents of cell membranes. This has enabledresearchers to understand what activates andinhibits the enzyme, which has potentialapplications in gene therapy, treating auto-immunedisease such as arthritis as well as targeted drug-delivery for cancer therapy.

Case Study 2: Schematic representation of the action of cobra venomPLA2 on a membrane

Case Study 1: Synthetic human elastin made in Professor Weiss'slab at the University of Sydney.

Instrument specifications:Platypus is located on the cold neutron guide CG3Wavelength Range: 2-20 ÅQ-range (liquids): 0 – 0.3 Å-1

Q-range (solids) : 0 – 0.5 Å-1

Δt/T (Δλ/λ) : 1-12%ΔQ/Q: 2-20%Rmin: 10-8

Off-Specular: yesPolarised: yesWhite flux @ sample: ~109 ncm-2s-1

Beam size: (0.05 – 20) x 50 mmSample-detector: 0.65 – 3.65 mDetector area: 500 x 250 mmDetector: high speed 2-dimensional areaChopper system: flexible 4-disc systemVertical scattering planePolarisation analysis: yes (specular reflectivity only)Temperature range: 4 K – 350 KMax. magnetic field at sample: 1 T

For more information contact:Dr Michael James: +61 2 9717 [email protected]

Dr Andrew Nelson: +61 2 9717 [email protected]

Dr Frank Klose (magnetic films): +61 2 9717 [email protected]

Quokka


QuokkaSmall-angle neutron scattering

Quokka is a state-of-the art small-angle neutronscattering (SANS) instrument. SANS is a highlyversatile technique for investigating a wide range ofmaterials including polymers, emulsions, colloids,superconductors, porous materials, geologicalsamples, alloys, ceramics and biological moleculessuch as proteins and membranes.

What makes Quokka special?

SANS is a powerful technique for looking atstructures on the nanoscale from 1 to 10nanometres. When a neutron beam impinges on asample, some neutrons scatter along a path thatdiffers from the transmitted beam by as little asseveral hundredths of a degree. This ‘small-angle’scattering provides information about relatively largestructural details on the molecular scale. SANS canprovide particle sizes, shapes and distributionsaveraged over a complete macroscopic sample.

Applications:

The major strength of the SANS technique is that itcan be used to investigate a host of materials,which cover a wide range of research disciplines.Materials that are routinely characterised using theSANS technique include; alloys, ceramics, biologicalmaterials, colloidal materials, complex fluids,polymers, surfaces and interfaces, flux lattices insuperconductors.

SANS is a versatile technique for investigating food components such as proteins, polymers and emulsions.

QUOKKA will be particularly important in the FoodScience project - a collaboration between ANSTO,CSIRO, Food Science Australia and the University ofQueensland. Participants are investigating scientificproblems of national significance for foodprocessing and human nutrition.

Neutron guide

Velocity selector

bunker

Gate valve

Sample position

Detector vessel

Collimation system



Case Study 1: Fighting obesity

SANS is helping scientists understand how thehuman body breaks down fats, by investigating themolecules that we produce in our digestivesystems to do this. 95% of fats eaten in theWestern diet are triglycerides, which require threedigestive components to break down in order to beabsorbed by the body. Two enzymes (pancreaticlipase and colipase) and bile salts come together toform an active complex to digest the fat. SANS isthe ideal technique to investigate this largemolecular structure, and scientists have been ableto unravel how these digestive molecules cometogether to break down fat.

From this understanding, there is the potential todesign drugs that can stop this active complex fromforming in the digestive system and thereforereduce the amount of fat assimilated into the body.

Case Study 2: Hydrogels for contact lenses

One of the main obstacles to successful extended-wear contact lenses has been the inability ofconventional hydrogels to prevent significantovernight corneal swelling caused by low oxygenpermeability. Other important properties of thehydrogels include biocompatibility, wettability,material strength and stability.

To improve materials suitability for extended wearcontact lenses, novel block copolymer materialswith high oxygen permeability in combination withsuperior hydration properties need to be developed.In order to understand this, the moleculararchitecture of diblock copolymers with phaseseparation on the nanoscale (to ensure opticalclarity) is being determined by SANS.

Instrument specifications:Quokka is located on the cold neutron guide CG1Wavelength range: 4.5 – 43 Åq-range: < 0.0008 < q / Å-1 < 1.0Source - sample distance: 1, 2, 4, 6, 8, 10,12,14, 16, 20 mSample - detector distance: 1 – 20 mGuides: 58Ni-equivalent guides (Ni/Mo-Ti)Maximum beam cross-section: 50 mm x 50 mmIncident beam polarisation: Fe/Si supermirrorEstimated flux at sample position: 4 x 107 ncm-2s-1

Detector area: 1m2 with horizontal offset by up to 450 mmOptics: MgF2 lens and prism focussing optics� Large sample area (standard connectors for

user-defined ancillaries)

� Provision for polarisation analysis, further optics, chopper

For more information contact:Dr Elliot Gilbert: +61 2 9717 [email protected]

Dr Bill Hamilton: +61 2 9717 [email protected]

Dr Richard Garrett: +61 2 9717 [email protected]

Case Study 2Case Study 1

Echidna


EchidnaHigh-resolution powder diffractometer

Echidna is a state-of-the-art high-resolutionpowder diffraction instrument. Structures thatcan be determined by powder diffractioninclude superconductors, pharmaceuticals,aerospace alloys, cements, minerals, zeolites,hydrogen storage media, and optical materials.

What makes Echidna special?

Echidna uses a single wavelength and a highlycollimated (non-divergent) beam of neutrons toimprove resolution. The high-resolution enablesclosely placed peaks in the diffraction pattern to beseparated. This diffraction technique can resolvestructures very accurately to provide precise atomicand magnetic structures of the sample.

Applications:

High-resolution powder diffraction can be used to:

� Determine structures of newly created materials,to better understand their properties.

� Study materials with light elements in thepresence of heavy ones (e.g. oxides, borides,carbides) and for magnetic materials.

� Measure strain, crystallite size, and defects inmaterials such as metals, hydrogen storage and electro-chemical materials, and mesoscopic structures

� Investigate materials that occur in a polycrystallineform under natural or industrial conditions

� Investigate materials with complex crystalstructures, including catalysts, hybrid materials,organics, cements, natural minerals, zeolites, andnonlinear optical materials.

� Study the structural phase transitions of ferroicand electronic materials such as superconductorsand magnetoresistive materials.

� Investigate bulk samples or samples in extreme environments (pressure, temperature,stress, magnetic and electric fields, orcombinations of these).

Relevant fields include: Solid-state physics,materials science, chemistry, geoscience, andengineering.



Case Study 1: Studying cement – making betterbuilding products

Using Echidna, cement manufacturers can take theguess work out of which additives to use and howto process them to engineer stronger cements. Asthe world's most popular building material it mayseem surprising that the main componentresponsible for cement's strength is not completelyunderstood structurally. This material, tricalciumsilicate, has a very complicated crystal structure andexists in several different crystal forms known aspolymorphs. Each polymorph can be stabilised incement and has different strength properties andusing a neutron diffraction instrument such asEchidna, is the only way to quantitatively determinethese forms in cement.

Case Study 2: Lithium batteries – increasing their life

Neutron diffraction is the only technique that can beused for studying real products in real life conditions.With neutrons, we can study a real battery instead ofa model electrochemical cell and follow phasetransformations in electrodes as a function ofcharge/discharge cycling or time under load.

With Echidna we can study:� phase composition of electrodes and weight

fractions of phases

� crystal structural characteristics

� particle size and microstrain

This reveals what is happening within the batteryduring the charging/recharging cycle and is essentialfor understanding mechanisms of capacity fade andperformance optimisation (capacity, charge/recharge life).

Instrument specifications:Echidna is located on the thermal neutron guide TG1Wavelength range: 1 – 3 Å (6.3 – 2.1 Å-1)Range of momentum transfer: 0.35 – 12.5 Å-1Max. beam size: 20mm wide by 50mm highFlux at sample position: up to 107 ncm-2s-1

Monochromators:

� Ge 115 monochromator, sagittal focussing with fixed radius - 24 crystal slabs

� Ge 335 monochromator, [-1 1 0] vertical allowing forasymmetric reflections, variable sagittal focussing

Detector:

� Typical scan time: 2-3 hours

� 128 position sensitive detectors of 25 mm diameterx 300 mm high (active length), 10 bar (chargedivision)

� 128 collimators with 5' collimation, 15 mm x 300 mm (W x H)

For more information contact:Dr Max Avdeev: +61 2 9717 [email protected]

Dr James Hester: +61 2 9717 [email protected]

Case Study 2Case Study 1

Wombat


WombatHigh-intensity powder diffractometer

Wombat is one of the most powerful high- intensitypowder diffractometers in the world.It has the power to detect a million neutrons asecond and to produce data on the structure ofmaterials in a matter of milliseconds.

What makes Wombat special?

� Able to determine crystal structures quickly forphase transitions, chemical reactions and kineticstudies with rapid real time measurements =(down to 30 Ìs)

� Able to analyse very small samples (approx 10 mg).

� Able to analyse samples in complex sampleenvironment(s), eg: in pressure cells

Applications:

Wombat can be used to study a range of materialsincluding, novel hydrogenstorage materials for cleanenergy storage of the future, pharmaceuticalmolecules, negative-thermal-expansion materials(materials that contract upon heating) and materialsfor fusion reactors.

The properties of a material are linked to its atomicstructure, which can be influenced by itsenvironment. The effects of temperature, pressure,applied fields (magnetic or electric) on the atomicstructure can affect the material’s properties and canbe measured by Wombat.

For example:

� Phase transitions – by varying one or more of thetemperature, applied magnetic/electric fields, orapplied pressure, the properties in a material canbe created or destroyed.

� Material formation – many materials undergo oneor more chemical reactions as a function of time asthey are formed e.g setting of cement

� Cyclic variations – materials periodically exposed toapplied fields resulting in changes to the atomicstructure.

� In-situ studies to observe chemical reactions andother dynamic phenomena as they occur

Monochromator

CollimatorSample stage 120° area

detector for high speed data

acquisition

Granite Dance

Floor

NeutronGuide



Case Study 1: Negative thermal expansionmaterials

Negative thermal expansion (NTE), or contractionupon heating, is of fundamental scientific interest andmay find applications in precision engineering. We can measure NTE through diffraction methods,following the evolution of the structure as a functionof temperature. Wombat’s exceptionally intenseneutron beam and fast detector enables the collectionof data in a few minutes rather than hours, makingthe collection of the large amount of data required fora variable temperature study of a series of samplesfeasible. One of the keys to creating materials withuseful thermal expansion properties is to ‘tune’ theexpansion behaviour through molecular modification.In the figure, the slope of the line is related to thecoefficient of thermal expansion, The thermalexpansion of the framework, LnM(CN)6, is ‘tuned’through substitution of the lanthanoid metal “Ln” (Ho or La) or the transition metal “M” (Co, Fe), andthrough inclusion of “guest” molecules (K, shownpurple in the structural representation) within theframework (leading to positive thermal expansion).

Case Study 2: Piezoelectric materials

Ceramic lead zirconate titanate (PZT) is a verypopular material for electromechanical transducerapplications due to its large piezoelectric responseand low cost. Devices such as ultrasoundgenerators, hydrophones, high-voltage generators,impact sensors, and micro-positioning systems arejust a few which take advantage of the exceptionalproperties of PZT. There are a whole range ofpiezoelectric materials based on the PZT structure,with the potential for applications to be explored.

Wombat will be used to perform rapid stroboscopicmeasurements to determine how these materialschange structure with the application of an electricfield, combined with longer duration measurementsto study fatiguing effects over time which can leadto device failure.

Case Study 2: Phase transition in PZN-8.5PTCase Study 1: Measuring the ‘tuning’ of thermal expansion inLnM(CN)6 using Wombat

Instrument specifications:Wombat is located on the thermal neutron guide TG1Wombat was built as a flexible modular instrument which can exploit the advantages of:� focussing neutron optics in the monochromator

system over a wide range of incident wavelengths

� a large solid angle detector with position sensitivedetection capabilities

� an advanced data acquisition electronics system

� an optional radial collimator for background reduction

� Wavelength ranges

0.9 - 2.4 Å (Ge monochromator)2.4 - 5.8 Å (PG monochromator with Be filter for >4 Å)

� Resolution Δd/d > ~ 2 x 10-3

� Beam size max. 20 mm (wide) x 60 mm (high)

� Sample weight ~10 mg to 10 g

� Typical sample size 1 cm3

� 1s acquisition for 10 mm3 (15 min for 1 mm3) in oneshot irreversible experiments

� 30 µs acquisition in stroboscopic mode (reversibleexperiments)

� Estimated flux at sample position >108 ncm-2s-1

� Detector area: continuous detection over 120°x 200 mm high

For more information contact:Dr Andrew Studer: +61 2 9717 [email protected]

Dr Vanessa Peterson: +61 2 9717 [email protected]

Kowari


KowariResidual stress diffractometer

Kowari is a residual stress diffractometer which can be used for ‘strain scanning’ of large engineeringcomponents weighing up to 1000 kilograms. The integrity of engineering components oftendepends on strains and stresses inside the material.For example, pipelines can fail if stresses exceed the‘ultimate tensile stress’.

What makes Kowari special?

Neutron diffraction is non-destructive techniqueapplicable to nearly all crystalline materials and canprovide sub-surface information not obtainable byany other technique. It can determine importantmechanical properties, to validate finite elementmodels, which predict mechanical behaviour forincreased reliable performance or lifetimepredictions. It is also used to compareexperimentally determined stresses with criticalmaterial characteristics. Mechanical strains andstresses can be revealed by measuring crystallattice deformations with neutron diffraction.Neutrons are capable of penetrating deep intomaterials making them a unique tool to obtain dataabout lattice deformations deep inside the sample.

2- and 3-dimensional stress maps can be obtained by translating and rotating the objectduring the experiment.

Applications:

The residual stress diffractometer can be used toreveal:

� Residual stresses in components and structuressuch as rails, pipelines, airplanes

� Stresses in coatings such as thermal barrier,wear resistant and corrosion resistant coatings

� Stress corrosion cracking due to extremeenvironments such as:- Heat + pressure (pressure pipes of power

generators)- Corrosive environment + stress (pipelines, steel

reinforcement in concrete)

� Fatigue, crack growth and development inmaterials undergoing contact stress, structuralcomponents and load-bearing parts.

In addition to its engineering applications, Kowari canalso be used to investigate new materials such asshape-memory alloys. These materials can return totheir original shape after bending or deformation andare used for example in medical aerospace applications.

Above: Residual stresses in a gas pipline connection can cause failure by fracture or stresscorrosion cracking. Right Top: Residual stresses are assumed to be at yield strength level(483MPa). The critical weld in this 400kg branch was measured on Kowari. Right bottom: Weldsection with longitudinal stresses superimposed. The maximum residule stress was 60% of yield.



Case Study: Neutrons put the brakes on stress

The juddering you feel when putting your foot onthe brakes is what happens when disc brake rotorsbecome distorted through normal use of the brakes.To the car manufacturer it’s called ‘runout’ and is amultimillion dollar warranty problem each year.

To test whether runout is caused by residualstresses from the manufacturing process or by justthe normal use of the brakes, neutrons were usedto analyse and compare new and used brake discs.

The results suggest that it is most likely that therunout is due to the uneven cooling of the hot discthrough use – from severe breaking, with largestresses found in the old worn out brake comparedto the new one.

Rather than from the relaxation of residual stressesin the brake discs from manufacture. With theinsight of neutrons, the auto industry can worktowards finding new ways to manufacturecomponents to overcome these problems.

Instrument specifications:Kowari is located on the thermal neutron guide TG3

� Resolution Δd/d ~3 x 10-3

� Variable wavelength between 1 - 2.4 Å, due tovariable take-off angle and (hkk) reflections fromSilicon monochromator (double focussing bend-perfect crystal)

� Intensity at sample position estimated to be in theorder of ≤ 107 ncm-2s-1 (dependent on e.g.monochromator settings or distance from themonochromator-sample)

� Maximum sample weight < 1 tonne

For more information contact:Dr Oliver Kirstein: +61 2 9717 [email protected]

Dr Vladimir Luzin: +61 2 9717 [email protected]

New brake discUsed brake disc

Koala


KoalaLaue diffractometer

Koala is one of the leading small-moleculecrystallography instruments in the world and can beused for determining the complex crystal structure of a wide range of chemicals and minerals.

What makes Koala special?

The diffraction patterns created when neutrons hit asample in Koala will allow scientists to determine thelocation of atoms within the crystal and provide them with information about the crystal’s structure and its properties.

Single-crystal neutron diffraction studies complementX-ray crystallography by revealing the precise positionsof light atoms such as hydrogen, which cannot bedetermined by X-ray methods. Studies can be donewithout deuteration of material.

Applications:

Koala will be useful for:

� Development and study of new pharmaceuticals -through diffraction studies of potential drugcandidates

� Modern synthetic chemistry research - usingdiffraction studies to fully determine specificinteratomic interactions of new compounds

� Advanced materials research - to identify materialsand to examine subtly different formulations at theinteratomic scale

� Minerals research - understanding of the structureof new phases and the effect of the processingconditions on different phases

� Distinguishing between iso-electronic species (eg. K+, Cl - or elements near each other in theperiodic table) eg C and N; N and O.

Relevant fields include: chemistry, physics, materialsscience, geology and biology.

Sample

Image platedetector

Neutron beam



Case Study: Unravelling complex compounds

Zinc cyanide (Zn(CN)2) is currently the subject ofintensive study in the context of materials whichexhibit Negative Thermal Expansion – that is,materials which contract on heating. The structureis composed of a pair of interpenetrant diamondoidnetworks in which the tetrahedral centres are thezinc atoms and these centres are linked via linearbridges formed by the cyanide groups. We areprobing the nature and extent of the ordering (ifany) of the carbon and nitrogen atom sites in theselinks by single crystal neutron diffraction usingKOALA (diffraction image above).

Instrument specifications:Koala is located on the thermal neutron guide TG3and uses a ‘white beam’ – that is a spectrum orrange of wavelengths – facilitating efficient use ofa large proportion of the available neutron beam.� Fast data collection: one structure per day for

larger crystals

� Small samples: ~ 0.1 mm3 or less with slowerdata collection

� Solid angle for quasi-Laue diffractometer about 3π

� Neutron wavelength is peaked at 1.4 Å

� Routine for crystals with primitive cell up to 20 Å3

� Q-range ~ 10 (sinθ/λ ~ 0.9 Å-1)

� Sample environment: 6 K to 800 K (standard), gas-environment (hydrogen, oxygen, inert), electric fields

� Structures with larger unit cells may be possibleusing smaller crystals

For more information contact:Dr Alison Edwards: +61 2 9717 [email protected]

Dr Ross Piltz: +61 2 9717 [email protected]

Taipan


TaipanTriple-axis spectrometer

Taipan is a triple-axis spectrometer used to measureneutron inelastic scattering, which is a key technique for the measurement of excitations inmaterials.These measurements provide information onthe forces between atoms, or between magneticmoments. Taipan will be one of the best thermal-beamtriple-axis spectrometers in the world, as it has beendesigned to maximise the number of neutrons thatreach the sample.

What makes Taipan special?

Triple-axis spectrometers:

� measure how much energy has been lost or gained by neutrons in the scattering process,providing information on the energy spectrum of the solid sample.

� interpret the scattering in terms of dynamics or howthe atoms move within the sample.

This is particularly important in understanding:

� how materials change structure (phase transitions,eg: from liquid to solid)

� other thermodynamic properties of solids (eg:specific heat, magnetic susceptibility). Taipan ishighly configurable and versatile, and has the mostintense thermal beams in the whole facility,together with the lowest background levels. Asubstantial number of diffraction experiments willbe performed on the instrument, particularly whenlooking for weak scattering effects.

Triple-axis spectrometry is based on inelastic neutronscattering, which occurs when the energy of theneutron changes as a result of interaction with thesample. Taipan uses inelastic scattering to investigatemolecular vibrations and magnetic properties, and canprovide information not accessible by any other means.

OPAL REACTOR

Main Shutter

Shielding wedges

VirtualSource

Saddle shield

Axis one

Axis two

Axis three

Sample table &goniometers

Sample rotation

angle

Sample

Beam stop

Predetector collimator

Analyser

Analysershielding wedges



Instrument overview:

The machine consists of three independent axes of rotation:

� the first axis monochromates the beam –selects neutrons of a particular energy

� the second axis is the sample to be studied,which scatters the beam

� the third axis is the analyser, which analysesthe energy of the scattered beam

Application: Study of superconductors

Superconductivity is a phenomenon occurring incertain materials at extremely low temperatures,characterised by exactly zero electrical resistanceand the exclusion of the interior magnetic field.

Superconductors are used to make some of themost powerful electromagnets known to man,including those used in MRI machines. They canalso be used for magnetic separation, whereweakly magnetic particles are extracted from abackground of less or non-magnetic particles, as inthe pigment industries.

Instrument specifications:Taipan is located on the thermal neutronguide TG4 in reactor beam hallBeam size: 50 x 180 mm high at reactor face

Angular ranges:

� 15° < 2θm < 85°

� -145° < 2θs < 115°

� -110°< 2θA < 110°

Monochromators:

� Pyrolytic Graphite (002) with Energy Range: ~ 5 – 60meV

� Copper (200) with Energy Range: ~ 14 – 160 meV

� 200 x 200 mm2 in 9 x 11 segments (W x H) withcontinuous horizontal and vertical focussing

Sample area:

� beam size at monochromator shielding exit 50 x 130mm (W x H)

� flux at sample position is projected to be ~ 2 x 108

ncm-2s-1 at 50 meV

Analyser:

� Pyrolytic Graphite (002) 24' mosaic

� 160 x 140 mm in 5 x 7 segments (W x H) withcontinuous horizontal and vertical focusing

Polarisation Analysis:

� Provided by m=3 polarising supermirror bendersbefore and after the sample

Soller collimators:

� Pre-monochromator collimators:15', 30', Open; 90 x185 mm2 (W x H)

� Post-monochromator, pre-analyser and pre-detector,collimators: 20', 40', Open; 50 x 130 mm2 (W x H)

Detector:

� 3He detector, Ø25 mm x 100 mm, p=10 bars

� or Ø50 mm x 100 mm, p=5 bars

For more information contact:Dr Sergey Danilkin: +61 2 9717 [email protected]

Dr Mohana Yethiraj: +61 2 9717 [email protected]

Dr Anton Stampfl: +61 2 9717 [email protected]

National Deuteration Facility Overview

The National Deuteration Facility (NDF) is co-fundedby ANSTO and the National Collaborative ResearchInfrastructure Strategy (NCRIS) initiative of theAustralian Government. It offers the facilities, staffand expertise to produce a wide variety ofdeuterated compounds for downstream analysissuch as small angle neutron scattering (SANS),neutron reflectometry, neutron crystallography andNuclear Magnetic Resonance (NMR).

What is deuteration?

Deuteration is the process where all or part of themolecular hydrogen (1H) of a compound is replacedby the stable (non-radioactive) isotope deuterium(2H). The nucleus of deuterium, also known as‘heavy hydrogen’, contains one proton and oneneutron unlike that of the far more commonhydrogen nucleus which contains no neutrons.

Why deuterate?

The different properties of the hydrogen anddeuterium nuclei mean they scatter neutrons quitedifferently. Neutron beam studies exploit thisdifference in scattering length densities to obtaindata for properties such as: molecular structure, theprecise location of hydrogen atoms, conformationalchanges and individual components ofmulticomponent systems that without deuteriumlabelling would otherwise be indistinguishable.

For NMR studies, the deuterium nucleus has adifferent spin quantum number to the hydrogennucleus, making it NMR silent in 1H NMRspectroscopy. Substituting deuterium for hydrogensremoves unwanted 1H-1H coupling, simplifying theanalysis of complex spectra

deuterium (D) hydrogen (H)

National Deuteration Facility


Neutron beam studies

Some examples of neutron beam studies where theuse of deuterated material would be advantageous;

Small angle neutron scattering (SANS)

Neutron scattering, deuterium labelling and contrastvariation allows determination of the shape andposition of subunits of multicomponent systemssuch as proteins and polymers. SANS can also beused to observe conformational changes inmolecules based on active or inactive states, orchanges in solution conditions. SANS, by providingquaternary structures, can complement dataobtained from microscopy, small angle x-rayscattering (SAXS), and high-resolution details fromNMR and/or crystallography.

Neutron reflectometry

Neutron reflectometry uses reflection of a neutronbeam from surfaces and interfaces to provide dataon thickness and topology. For example, deuteratedlipids can be assembled into model biologicalmembranes. This technique can obtain informationabout the conformation and position of membrane-associated proteins and dimensions and order ofassembled layers in systems such as chemical andbiosensors.

Neutron crystallography

Another technique that can be used with deuteratedmolecules is that of neutron crystallography. The use of neutrons as opposed to x-rays givesbetter location of hydrogen atoms in proteincrystals. The use of deuterated protein reduces thesize of the crystal needed to achieve this byreducing the “noise” from incoherent scatteringresulting from 1H.

National Deuteration Facility




Methods of deuteration

The NDF offers molecular deuteration using eitherin vivo biodeuteration or chemical deuterationtechniques.

Biological deuteration

Biodeuteration involves the growth of microbialcultures (most commonly E. coli) in heavy water(D2O) supplemented with either a deuterated orhydrogenated carbon compound, depending on thelevel of deuteration required. The biomass isharvested and the deuterated molecule is purifiedand characterised.

Chemical deuteration

Chemical deuteration involves deuterating wholemolecules or building blocks for the synthesis of adesired molecule by exposing them to D2O at hightemperatures and pressures in the presence of acatalyst. If required, compounds can then besynthesised from the deuterated building blocksusing organic chemistry techniques.

Capabilities of the NDF

The NDF is capable of deuterating a wide variety ofmolecules either biologically or chemically. Thefollowing list shows the diversity of moleculessuccessfully deuterated by the NDF to date.

Biologically

� Recombinant prokaryotic and eukaryotic proteins

� DNA and biopolymers

� Algal hydrolysate as a deuterated substrate formicrobial growth

� Future development of polysaccharides and lipids

Chemically

� Saturated fatty acids (Octanoic, Nonanoic, Lauric,Palmitic, Stearic) and di-acids (Azelaic, Sebacic)

� Alcohols and brominated alkanes

� CTAB, Diethylene glycol, SDS and lipids

Instruments available at the NDF

The NDF houses five biodeuteration laboratoriesand two chemical deuteration laboratories.

The Biodeuteration Laboratories consist of amolecular biology lab, a fermentation lab, acharacterisation lab, a chromatography lab and apreparative lab. All are equipped with state-of-the-art instruments including:

� 15L, 5L and 2L (x6) bioreactors for microbialgrowth

� 3L Photobiorector for photosynthetic growth

� 2 AKTA chromatography systems for purification

� Circular Dichroism Spectrometer, DifferentialScanning Calorimeter and Dynamic LightScattering Instruments for molecularcharacterisation.

The Chemical Deuteration Laboratories consist of asynthesis lab and a characterisation lab which arealso equipped with state-of-the-art instrumentsincluding:

� Parr Reactors for deuteration of small molecules

� Gel Permeation Chromatography for fractionationand molecular weight characterisation ofpolymers.

� NMR, prep HPLC, LC-MS/MS, polarimeter andFT-IR for further molecular characterisation

For more information contact:Professor Peter HoldenDirector – The National Deuteration FacilityTel: +61 2 9717 [email protected]

Australian Nuclear Science and Technology Organisation

Access to ANSTO’s neutron-beam instruments is by peer review basedon merit. There is no charge for beam time if results are published in theopen literature. There will be two calls a year for proposals using anonline submission system: http://neutron.ansto.gov.au;

for more details please see

www.ansto.gov.au/research/bragg_institute/users/requesting_beam_time

or call the Bragg User Office on +61 (0)2 9717 9458

or email us [email protected].

Access for proprietary work is available on a fee-for-service basis.

Please contact [email protected] or visit

www.ansto.gov.au/commercial_services

The Australian Nuclear Science and Technology Organisation (ANSTO) isthe home of Australia’s nuclear science expertise. This unique expertise is applied to radiopharmaceutical production andresearch, climate change research, water resource management,materials engineering, neutron scattering and a range of other scientific research disciplines.

ANSTO is a Federal Government agency and operates Australia’s onlynuclear reactor OPAL - used for research and isotope production. ANSTOapplies nuclear science in a wide range of areas for the benefit of all Australians.

New Illawarra Road, Lucas Heights NSW 2234

Postal Address: PMB 1, Menai NSW 2234

T +61 2 9717 3111

F +61 2 9543 5097

E [email protected]

www.ansto.gov.au

Printed October 2009

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