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Sample records for temperature x-ray diffraction

  1. High-pressure powder x-ray diffraction experiments on Zn at low temperature

    CERN Document Server

    Takemura, K; Fujihisa, H; Kikegawa, T

    2002-01-01

    High-pressure powder x-ray diffraction experiments have been performed on Zn with a He-pressure medium at low temperature. When the sample was compressed in the He medium at low temperature, large nonhydrostaticity developed, yielding erroneous lattice parameters. On the other hand, when the pressure was changed at high temperatures, good hydrostaticity was maintained. No anomaly in the volume dependence of the c/a axial ratio has been found.

  2. Characterization of polymorphic solid-state changes using variable temperature X-ray powder diffraction

    DEFF Research Database (Denmark)

    Karjalainen, Milja; Airaksinen, Sari; Rantanen, Jukka

    2005-01-01

    The aim of this study was to use variable temperature X-ray powder diffraction (VT-XRPD) to understand the solid-state changes in the pharmaceutical materials during heating. The model compounds studied were sulfathiazole, theophylline and nitrofurantoin. This study showed that the polymorph form...... of sulfathiazole SUTHAZ01 was very stable and SUTHAZ02 changed as a function of temperature to SUTHAZ01. Theophylline monohydrate changed via its metastable form to its anhydrous form during heating and nitrofurantoin monohydrate changed via amorphous form to its anhydrous form during heating. The crystallinity...... of SUTHAZ01, SUTHAZ02 and theophylline monohydrate were very high and stable. Nitrofurantoin monohydrate was also very crystalline at room temperature but during heating at lower temperatures the crystallinity decreased and started to increase strongly at the temperature where the sample had changed...

  3. Thermodynamic properties and low-temperature X-ray diffraction of vitamin B{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Knyazev, A.V., E-mail: knyazevav@gmail.com; Smirnova, N.N.; Shipilova, A.S.; Shushunov, A.N.; Gusarova, E.V; Knyazeva, S.S.

    2015-03-20

    Highlights: • Temperature dependence of heat capacity of vitamin B{sub 3} has been measured by precision adiabatic vacuum calorimetry. • The thermodynamic functions of the vitamin B{sub 3} have been determined for the range from T → 0 to 346 K. • The thermodynamic analysis of reactions involving nicotinic acid was made. • The low-temperature X-ray diffraction was used for the determination of coefficients of thermal expansion. - Abstract: In the present work temperature dependence of heat capacity of vitamin B{sub 3} (nicotinic acid) has been measured for the first time in the range from 5 to 346 K by precision adiabatic vacuum calorimetry. Based on the experimental data, the thermodynamic functions of the vitamin B{sub 3}, namely, the heat capacity, enthalpy H°(T) – H°(0), entropy S°(T) – S°(0) and Gibbs function G°(T) – H°(0) have been determined for the range from T → 0 to 343 K. The value of the fractal dimension D in the function of multifractal generalization of Debye’s theory of the heat capacity of solids was estimated and the character of heterodynamics of structure was detected. The thermodynamic parameters Δ{sub f}S°, Δ{sub f}G° at T = 298.15 K and p = 0.1 MPa have been calculated. The thermodynamic analysis of reactions involving nicotinic acid was made. The low-temperature X-ray diffraction was used for the determination of coefficients of thermal expansion.

  4. Diffractive X-ray Telescopes

    OpenAIRE

    Skinner, Gerald K

    2010-01-01

    Diffractive X-ray telescopes using zone plates, phase Fresnel lenses, or related optical elements have the potential to provide astronomers with true imaging capability with resolution several orders of magnitude better than available in any other waveband. Lenses that would be relatively easy to fabricate could have an angular resolution of the order of micro-arc-seconds or even better, that would allow, for example, imaging of the distorted space- time in the immediate vicinity of the super...

  5. Kinetics of methane hydrate decomposition studied via in situ low temperature X-ray powder diffraction.

    Science.gov (United States)

    Everett, S Michelle; Rawn, Claudia J; Keffer, David J; Mull, Derek L; Payzant, E Andrew; Phelps, Tommy J

    2013-05-02

    Gas hydrate is known to have a slowed decomposition rate at ambient pressure and temperatures below the melting point of ice. As hydrate exothermically decomposes, gas is released and water of the clathrate cages transforms into ice. Based on results from the decomposition of three nominally similar methane hydrate samples, the kinetics of two regions, 180-200 and 230-260 K, within the overall decomposition range 140-260 K, were studied by in situ low temperature X-ray powder diffraction. The kinetic rate constants, k(a), and the reaction mechanisms, n, for ice formation from methane hydrate were determined by the Avrami model within each region, and activation energies, E(a), were determined by the Arrhenius plot. E(a) determined from the data for 180-200 K was 42 kJ/mol and for 230-260 K was 22 kJ/mol. The higher E(a) in the colder temperature range was attributed to a difference in the microstructure of ice between the two regions.

  6. Temperature-Dependent X-ray Diffraction Measurements of Infrared Superlattices Grown by MBE

    Directory of Open Access Journals (Sweden)

    Charles J. Reyner

    2016-11-01

    Full Text Available Strained-layer superlattices (SLSs are an active research topic in the molecular beam epitaxy (MBE and infrared focal plane array communities. These structures undergo a >500 K temperature change between deposition and operation. As a result, the lattice constants of the substrate and superlattice are expected to change by approximately 0.3%, and at approximately the same rate. However, we present the first temperature-dependent X-ray diffraction (XRD measurements of SLS material on GaSb and show that the superlattice does not contract in the same manner as the substrate. In both InAs/InAs0.65Sb0.35 and In0.8Ga0.2As/InAs0.65Sb0.35 SLS structures, the apparent out-of-plane strain states of the superlattices switch from tensile at deposition to compressive at operation. These changes have ramifications for material characterization, defect generation, carrier lifetime, and overall device performance of superlattices grown by MBE.

  7. Using Variable Temperature Powder X-Ray Diffraction to Determine the Thermal Expansion Coefficient of Solid MgO

    Science.gov (United States)

    Corsepius, Nicholas C.; DeVore, Thomas C.; Reisner, Barbara A.; Warnaar, Deborah L.

    2007-01-01

    A laboratory exercise was developed by using variable temperature powder X-ray diffraction (XRD) to determine [alpha] for MgO (periclase)and was tested in the Applied Physical Chemistry and Materials Characterization Laboratories at James Madison University. The experiment which was originally designed to provide undergraduate students with a…

  8. Nanocalorimeter platform for in situ specific heat measurements and x-ray diffraction at low temperature

    Science.gov (United States)

    Willa, K.; Diao, Z.; Campanini, D.; Welp, U.; Divan, R.; Hudl, M.; Islam, Z.; Kwok, W.-K.; Rydh, A.

    2017-12-01

    Recent advances in electronics and nanofabrication have enabled membrane-based nanocalorimetry for measurements of the specific heat of microgram-sized samples. We have integrated a nanocalorimeter platform into a 4.5 T split-pair vertical-field magnet to allow for the simultaneous measurement of the specific heat and x-ray scattering in magnetic fields and at temperatures as low as 4 K. This multi-modal approach empowers researchers to directly correlate scattering experiments with insights from thermodynamic properties including structural, electronic, orbital, and magnetic phase transitions. The use of a nanocalorimeter sample platform enables numerous technical advantages: precise measurement and control of the sample temperature, quantification of beam heating effects, fast and precise positioning of the sample in the x-ray beam, and fast acquisition of x-ray scans over a wide temperature range without the need for time-consuming re-centering and re-alignment. Furthermore, on an YBa2Cu3O7-δ crystal and a copper foil, we demonstrate a novel approach to x-ray absorption spectroscopy by monitoring the change in sample temperature as a function of incident photon energy. Finally, we illustrate the new insights that can be gained from in situ structural and thermodynamic measurements by investigating the superheated state occurring at the first-order magneto-elastic phase transition of Fe2P, a material that is of interest for magnetocaloric applications.

  9. Low Temperature X-Ray Diffraction Study on CaFe2As2

    Science.gov (United States)

    Huyan, Shuyuan; Deng, Liangzi; Wu, Zheng; Zhao, Kui; Lv, Bing; Xue, Yiyu; Chu, Ching-Wu; B. Lv Collaboration; HPLT (Paul C. W. Chu) Team

    For undoped CaFe2As2 single crystals, we observed that utilizing thermal treatments could stabilize two pure tetragonal phases PI and PII. Both phases are non-superconducting, while the superconductivity with a Tc up to 25 K can be induced through proper thermal treatment. Room temperature X-ray studies suggest that the origin of superconductivity arises from the interface of the mesoscopically stacked layers of PI and PII. To further investigate, a systematic low temperature X-ray study was conducted over a series of thermal treated CaFe2As2 single crystals. From which, we observed the phase aggregation of PI and PII upon cooling, more importantly, an ordered stacking structure exists at low temperature, which closely related to superconducting volume fraction and the ratio of PI and PII. These results further support the proposal of interface-enhanced superconductivity in undoped CaFe2As2. UT Dallas

  10. Diffractive X-Ray Telescopes

    Science.gov (United States)

    Skinner, Gerald K.

    2010-01-01

    Diffractive X-ray telescopes, using zone plates, phase Fresnel lenses, or related optical elements have the potential to provide astronomers with true imaging capability with resolution many orders of magnitude better than available in any other waveband. Lenses that would be relatively easy to fabricate could have an angular resolution of the order of micro-arc-seconds or even better, that would allow, for example, imaging of the distorted spacetime in the immediate vicinity of the super-massive black holes in the center of active galaxies. What then is precluding their immediate adoption? Extremely long focal lengths, very limited bandwidth, and difficulty stabilizing the image are the main problems. The history, and status of the development of such lenses is reviewed here and the prospects for managing the challenges that they present are discussed.

  11. X-ray diffraction and electroresistance measurements under high pressure and temperature using a large-volume cell

    Energy Technology Data Exchange (ETDEWEB)

    Principi, E; Minicucci, M [CNISM, CNR-INFM SOFT and Dipartimento di Fisica Universita degli Studi di Camerino via Madonna delle Carceri 62032, Camerino (Italy); Di Cicco, A

    2008-07-15

    In this communication we report about original experimental techniques for in-house x-ray diffraction and electrical resistance measurements under high-temperature and high pressure conditions, using large volume cells in the opposite anvil recessed geometry. The high-pressure devices we are currently using are a compact Paris-Edinburgh (PE) V5 150 Tons press and a 50 Tons standard hydraulic press, coupled usually with WC anvils and 10 mm or 7 mm boron-epoxy or pyrophyllite biconical gaskets for x-ray diffraction and resistance measurements respectively. Limiting pressures, using such a non-toroidal sample assembly and WC anvils, are about 10 GPa on samples of large sizes (10-20 mm{sup 3}). Samples can be heated using an hollow graphite cylinder as a crucible reaching temperatures as high as 2300 K, while the temperature can be measured up to 1300 K by using a K-type thermocouple. The highly automated setup developed for resistance measurements is described in details. In particular, we present electroresistance measurements of Bi melting under pressure and measurements of the Ge and LiF EOS (equation of state) at high temperature and pressure obtained using x-ray diffraction showing the sensitivity of the techniques. The relevance of these experiments to the exploitation of the potential of equipments available at synchrotron radiation facilities is emphasized.

  12. A high-pressure vessel for X-ray diffraction experiments for liquids in a wide temperature range

    CERN Document Server

    Hosokawa, S

    2001-01-01

    An internally heated high-pressure vessel was developed for angle-dispersive X-ray scattering experiments on liquids at high-temperatures and high-pressures. It consists of a closed-end Al cylinder and a steel flange. Continuous windows made of Be cover a scattering angle range up to 55 deg. In combination with a single-crystal sapphire cell and a small heating system inside the vessel, we were able to carry out diffraction measurements for liquids in a wide temperature range up to 2000 K at high pressures up to 150 bars. Some of our recent X-ray scattering experiments using synchrotron radiation, such as inelastic scattering, high-energy elastic scattering, and anomalous scattering, are also reported.

  13. Multiscale measurements on temperature-dependent deformation of a textured magnesium alloy with synchrotron x-ray imaging and diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Lu, L.; Bie, B. X.; Li, Q. H.; Sun, T.; Fezzaa, K.; Gong, X. L.; Luo, S. N.

    2017-06-01

    In situ synchrotron x-ray imaging and diffraction are used to investigate deformation of a rolled magnesium alloy under uniaxial compression at room and elevated temperatures along two different directions. The loading axis (LA) is either perpendicular or parallel to the normal direction, and these two cases are referred to as LA⊥ and LAk loading, respectively. Multiscale measurements including stressestrain curves (macroscale), strain fields (mesoscale), and diffraction patterns (microscale) are obtained simultaneously. Due to initial texture, f1012g extension twinning is predominant in the LA⊥ loading, while dislocation motion prevails in the LAk loading. With increasing temperature, fewer f1012g extension twins are activated in the LA⊥ samples, giving rise to reduced strain homogenization, while pyramidal slip becomes readily activated, leading to more homogeneous deformation for the LAk loading. The difference in the strain hardening rates is attributed to that in strain field homogenization for these two loading directions

  14. Two-dimensional x-ray diffraction

    CERN Document Server

    He, Bob B

    2009-01-01

    Written by one of the pioneers of 2D X-Ray Diffraction, this useful guide covers the fundamentals, experimental methods and applications of two-dimensional x-ray diffraction, including geometry convention, x-ray source and optics, two-dimensional detectors, diffraction data interpretation, and configurations for various applications, such as phase identification, texture, stress, microstructure analysis, crystallinity, thin film analysis and combinatorial screening. Experimental examples in materials research, pharmaceuticals, and forensics are also given. This presents a key resource to resea

  15. X-ray microimaging by diffractive techniques

    Energy Technology Data Exchange (ETDEWEB)

    Kirz, Janos; Jacobsen, Chris

    2001-07-31

    The report summarizes the development of soft x-ray microscopes at the National Synchrotron Light Source X-1A beamline. We have developed a soft x-ray microscopy beamline (X-1A) at the National Synchrotron Light Source at Brookhaven National Laboratory. This beamline has been upgraded recently to provide two endstations dedicated to microscopy experiments. One endstation hosts a brand new copy of the redesigned room temperature scanning x-ray microscope (STXM), and the other end station hosts a cryo STXM and the original redesigned room temperature microscope, which has been commissioned and has started operation. Cryo STXM and the new microscope use the same new software package, running under the LINUX operating system. The new microscope is showing improved image resolution and extends spectromicroscopy to the nitrogen, oxygen and iron edges. These microscopes are used by us, and by users of the facility, to image hydrated specimens at 50 nm or better spatial resolution and with 0.1-0.5 eV energy resolution. This allows us to carry out chemical state mapping in biological, materials science, and environmental and colloidal science specimens. In the cryo microscope, we are able to do chemical state mapping and tomography of frozen hydrated specimens, and this is of special importance for radiation-sensitive biological specimens. for spectromicroscopic analysis, and methods for obtaining real-space images from the soft x-ray diffraction patterns of non-crystalline specimens. The user program provides opportunities for collaborators and other groups to exploit the techniques available and to develop them further. We have also developed new techniques such as an automated method for acquiring ''stacks'' of images.

  16. Multiple beam x-ray diffraction tomography

    Energy Technology Data Exchange (ETDEWEB)

    Kewish, C.M.; Davis, J.R.; Coyle, R.A. [Monash University, Clayton, VIC (Australia). Department of Physics

    1999-12-01

    Full text: X-ray diffraction computed tomography (XDT) is an imaging modality that utilises scattered x-rays to reconstruct an image. Since its inception in 1985, various detection scenarios and imaging techniques have been developed to demonstrate the accuracy and applicability of XDT. Many of the previous methods for measuring the scattered x-rays from an object utilise detectors that accept x-rays scattered from the entire length of the raypath through the object. The detector apertures must therefore have dimensions similar to the largest width of the scanned object. This creates a situation where the detected x-rays are not derived from a single scattering angle. A new method of scanning the x-rays scattered from an object is presented which allows quantitative determination of the spatial distribution of differential scattering cross section within a cross-sectional plane of the object. The new method incorporates a position sensitive detector and an arrangement of Soller slits. The acquired data represents both spatial and angular information. For each raypath through the object, a partial diffraction projection is measured at the off-axis detector and a set of diffraction projections is assembled by combining the diffracted signal from all rays through the object. A reconstruction strategy that accounts for attenuation of the primary beam and the scattered beam allows us to reconstruct a map of the differential scattering cross section in the sample for a given angle. Copyright (1999) Australian X-ray Analytical Association Inc. 3 refs.

  17. A novel diamond anvil cell for x-ray diffraction at cryogenic temperatures manufactured by 3D printing

    Science.gov (United States)

    Jin, H.; Woodall, C. H.; Wang, X.; Parsons, S.; Kamenev, K. V.

    2017-03-01

    A new miniature high-pressure diamond anvil cell was designed and constructed using 3D micro laser sintering technology. This is the first application of the use of rapid prototyping technology to construct high-pressure apparatus. The cell is specifically designed for use as an X-ray diffraction cell that can be used with commercially available diffractometers and open-flow cryogenic equipment to collect data at low temperature and high pressure. The cell is constructed from stainless steel 316L and is about 9 mm in diameter and 7 mm in height, giving it both small dimensions and low thermal mass, and it will fit into the cooling envelope of a standard CryostreamTM cooling system. The cell is clamped using a customized miniature buttress thread of diameter 7 mm and pitch of 0.5 mm enabled by 3D micro laser sintering technology; such dimensions are not attainable using conventional machining. The buttress thread was used as it has favourable uniaxial load properties allowing for higher pressure and better anvil alignment. The clamp can support the load of at least 1.5 kN according to finite element analysis (FEA) simulations. FEA simulations were also used to compare the performance of the standard thread and the buttress thread, and demonstrate that stress is distributed more uniformly in the latter. Rapid prototyping of the pressure cell by the laser sintering resulted in a substantially higher tensile yield strength of the 316L stainless steel (675 MPa compared to 220 MPa for the wrought type of the same material), which increased the upper pressure limit of the cell. The cell is capable of reaching pressures of up to 15 GPa with 600 μm diameter culets of diamond anvils. Sample temperature and pressure changes on cooling were assessed using X-ray diffraction on samples of NaCl and HMT-d12.

  18. Development of a new micro-furnace for "in situ" high-temperature single crystal X-ray diffraction measurements

    Science.gov (United States)

    Alvaro, Matteo; Angel, Ross J.; Marciano, Claudio; Zaffiro, Gabriele; Scandolo, Lorenzo; Mazzucchelli, Mattia L.; Milani, Sula; Rustioni, Greta; Domeneghetti, Chiara M.; Nestola, Fabrizio

    2015-04-01

    Several experimental methods to reliably determine elastic properties of minerals at non-ambient conditions have been developed. In particular, different techniques for generating high-pressure and high-temperature have been successfully adopted for single-crystal and powder X-ray diffraction measurements. High temperature devices for "in-situ" measurements should provide the most controlled isothermal environment as possible across the entire sample. It is intuitive that in general, thermal gradients across the sample increase as the temperature increases. Even if the small isothermal volume required for single-crystal X-ray diffraction experiments makes such phenomena almost negligible, the design of a furnace should also aim to reduce thermal gradients by including a large thermal mass that encloses the sample. However this solution often leads to complex design that results in a restricted access to reciprocal space or attenuation of the incident or diffracted intensity (with consequent reduction of the accuracy and/or precision in lattice parameter determination). Here we present a newly-developed H-shaped Pt-Pt/Rh resistance microfurnace for in-situ high-temperature single-crystal X-ray diffraction measurements. The compact design of the furnace together with the long collimator-sample-detector distance allows us to perform measurements up to 2θ = 70° with no further restrictions on any other angular movement. The microfurnace is equipped with a water cooling system that allows a constant thermal gradient to be maintained that in turn guarantees thermal stability with oscillations smaller than 5°C in the whole range of operating T of room-T to 1200°C. The furnace has been built for use with a conventional 4-circle Eulerian geometry equipped with point detector and automated with the SINGLE software (Angel and Finger 2011) that allows the effects of crystal offsets and diffractometer aberrations to be eliminated from the refined peak positions by the 8

  19. Single Particle X-ray Diffractive Imaging

    Energy Technology Data Exchange (ETDEWEB)

    Bogan, M J; Benner, W H; Boutet, S; Rohner, U; Frank, M; Seibert, M; Maia, F; Barty, A; Bajt, S; Riot, V; Woods, B; Marchesini, S; Hau-Riege, S P; Svenda, M; Marklund, E; Spiller, E; Hajdu, J; Chapman, H N

    2007-10-01

    In nanotechnology, strategies for the creation and manipulation of nanoparticles in the gas phase are critically important for surface modification and substrate-free characterization. Recent coherent diffractive imaging with intense femtosecond X-ray pulses has verified the capability of single-shot imaging of nanoscale objects at sub-optical resolutions beyond the radiation-induced damage threshold. By intercepting electrospray-generated particles with a single 15 femtosecond soft-X-ray pulse, we demonstrate diffractive imaging of a nanoscale specimen in free flight for the first time, an important step toward imaging uncrystallized biomolecules.

  20. X-ray filter for x-ray powder diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Sinsheimer, John Jay; Conley, Raymond P.; Bouet, Nathalie C. D.; Dooryhee, Eric; Ghose, Sanjit

    2018-01-23

    Technologies are described for apparatus, methods and systems effective for filtering. The filters may comprise a first plate. The first plate may include an x-ray absorbing material and walls defining first slits. The first slits may include arc shaped openings through the first plate. The walls of the first plate may be configured to absorb at least some of first x-rays when the first x-rays are incident on the x-ray absorbing material, and to output second x-rays. The filters may comprise a second plate spaced from the first plate. The second plate may include the x-ray absorbing material and walls defining second slits. The second slits may include arc shaped openings through the second plate. The walls of the second plate may be configured to absorb at least some of second x-rays and to output third x-rays.

  1. A facility for X-ray diffraction in magnetic fields up to 25 T and temperatures between 15 and 295 K

    Energy Technology Data Exchange (ETDEWEB)

    Wang, S.; Kovalev, A. E., E-mail: kovalev@magnet.fsu.edu; Suslov, A. V. [National High Magnetic Field Laboratory, Tallahassee, Florida 32310 (United States); Siegrist, T. [National High Magnetic Field Laboratory, Tallahassee, Florida 32310 (United States); Department of Chemical & Biomedical Engineering, FAMU-FSU College of Engineering, Tallahassee, Florida 32310 (United States)

    2015-12-15

    A facility for X-ray diffraction has been developed at the National High Magnetic Field Laboratory. It brings diffraction capability to the 25 T Florida split coil magnet and implements temperature control in a range of 15–295 K using a cold finger helium cryostat. This instrument represents an alternative to pulsed magnetic field systems, and it exceeds the static magnetic fields currently available at synchrotron facilities. Magnetic field compatibility of an X-ray source and detectors with the sizable magnetic fringe fields emanating from the magnet constrained the design of the diffractometer.

  2. X-ray diffraction study of low-temperature phase transformations in nickel-titanium orthodontic wires.

    Science.gov (United States)

    Iijima, M; Brantley, W A; Guo, W H; Clark, W A T; Yuasa, T; Mizoguchi, I

    2008-11-01

    Employ conventional X-ray diffraction (XRD) to analyze three clinically important nickel-titanium orthodontic wire alloys over a range of temperatures between 25 and -110 degrees C, for comparison with previous results from temperature-modulated differential scanning calorimetry (TMDSC) studies. The archwires selected were 35 degrees C Copper Ni-Ti (Ormco), Neo Sentalloy (GAC International), and Nitinol SE (3M Unitek). Neo Sentalloy, which exhibits superelastic behavior, is marketed as having shape memory in the oral environment, and Nitinol SE and 35 degrees C Copper Ni-Ti also exhibit superelastic behavior. All archwires had dimensions of 0.016in.x0.022in. (0.41 mm x 0.56 mm). Straight segments cut with a water-cooled diamond saw were placed side-by-side to yield a 1 cm x 1cm test sample of each wire product for XRD analysis (Rint-Ultima(+), Rigaku) over a 2theta range from 30 degrees to 130 degrees and at successive temperatures of 25, -110, -60, -20, 0 and 25 degrees C. The phases revealed by XRD at the different analysis temperatures were in good agreement with those found in previous TMDSC studies of transformations in these alloys, in particular verifying the presence of R-phase at 25 degrees C. Precise comparisons are not possible because of the approximate nature of the transformation temperatures determined by TMDSC and the preferred crystallographic orientation present in the wires. New XRD peaks appear to result from low-temperature transformation in martensite, which a recent transmission electron microscopy (TEM) study has shown to arise from twinning. While XRD is a useful technique to study phases in nickel-titanium orthodontic wires and their transformations as a function of temperature, optimum insight is obtained when XRD analyses are combined with complementary TMDSC and TEM study of the wires.

  3. Diffraction leveraged modulation of X-ray pulses using MEMS-based X-ray optics

    Science.gov (United States)

    Lopez, Daniel; Shenoy, Gopal; Wang, Jin; Walko, Donald A.; Jung, Il-Woong; Mukhopadhyay, Deepkishore

    2016-08-09

    A method and apparatus are provided for implementing Bragg-diffraction leveraged modulation of X-ray pulses using MicroElectroMechanical systems (MEMS) based diffractive optics. An oscillating crystalline MEMS device generates a controllable time-window for diffraction of the incident X-ray radiation. The Bragg-diffraction leveraged modulation of X-ray pulses includes isolating a particular pulse, spatially separating individual pulses, and spreading a single pulse from an X-ray pulse-train.

  4. High resolution X-ray diffraction studies on unirradiated and ...

    Indian Academy of Sciences (India)

    High-resolution X-ray diffraction technique, employing a three-crystal monochromator–collimator combination is used to study the irradiation induced defects in flux grown Sr-hexaferrite crystals irradiated with 50 MeV Li3+ ion beams at room temperature with a fluence value of 1 × 1014 ions/cm2. The diffraction curves of the ...

  5. High-pressure, high-temperature deformation of dunite, eclogite, clinopyroxenite and garnetite using in situ X-ray diffraction

    Science.gov (United States)

    Farla, R.; Rosenthal, A.; Bollinger, C.; Petitgirard, S.; Guignard, J.; Miyajima, N.; Kawazoe, T.; Crichton, W. A.; Frost, D. J.

    2017-09-01

    The rheology of eclogite, garnetite and clinopyroxenite in the peridotitic upper mantle was experimentally investigated in a large volume press combined with in situ synchrotron X-ray diffraction techniques to study the impact on mantle convection resulting from the subduction of oceanic lithosphere. Experiments were carried out over a range of constant strain rates (2 ×10-6- 3 ×10-5 s-1), pressures (4.3 to 6.7 GPa) and temperatures (1050 to 1470 K). Results show substantial strength variations among eclogitic garnet and clinopyroxene and peridotitic olivine. At low temperatures (1400 K) eclogite is weaker than dunite by 0.2 GPa or more. Garnetite and clinopyroxenite exhibit higher strength than dunite at approximately 1200 K. However, at higher temperature (1370 K), clinopyroxenite is significantly weaker than garnetite (and dunite) by more than a factor of five. We explain these observations by transitions in deformation mechanisms among the mineral phases. In clinopyroxene, high temperature dislocation creep resulting in a strength reduction replaces low temperature twinning. Whereas garnet remains very rigid at all experimental conditions when nominally anhydrous ('dry'). Microstructural observations show phase segregation of clinopyroxene and garnet, development of a crystallographic and shape preferred orientation in the former but not in the latter, suggesting an overall weak seismic anisotropy. Detection of eclogite bodies in the peridotite-dominated mantle may only be possible via observation of high VP /VS1 ratios. A comparable or weaker rheology of eclogite to dunite suggests effective stirring and mixing of eclogite in the convecting mantle.

  6. Nanocalorimeter platform for in situ specific heat measurements and x-ray diffraction at low temperature

    Energy Technology Data Exchange (ETDEWEB)

    Willa, K. [Materials Science Division, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, Illinois 60439, USA; Diao, Z. [Department of Physics, Stockholm University, SE-106 91 Stockholm, Sweden; Laboratory of Mathematics, Physics and Electrical Engineering, Halmstad University, P.O. Box 823, SE-301 18 Halmstad, Sweden; Campanini, D. [Department of Physics, Stockholm University, SE-106 91 Stockholm, Sweden; Welp, U. [Materials Science Division, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, Illinois 60439, USA; Divan, R. [Center for Nanoscale Materials, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, Illinois 60439, USA; Hudl, M. [Department of Physics, Stockholm University, SE-106 91 Stockholm, Sweden; Islam, Z. [X-ray Science Division, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, Illinois 60439, USA; Kwok, W. -K. [Materials Science Division, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, Illinois 60439, USA; Rydh, A. [Department of Physics, Stockholm University, SE-106 91 Stockholm, Sweden

    2017-12-01

    Recent advances in electronics and nanofabrication have enabled membrane-based nanocalorimetry for measurements of the specific heat of microgram-sized samples. We have integrated a nanocalorimeter platform into a 4.5 T split-pair vertical-field magnet to allow for the simultaneous measurement of the specific heat and x-ray scattering in magnetic fields and at temperatures as low as 4 K. This multi-modal approach empowers researchers to directly correlate scattering experiments with insights from thermodynamic properties including structural, electronic, orbital, and magnetic phase transitions. The use of a nanocalorimeter sample platform enables numerous technical advantages: precise measurement and control of the sample temperature, quantification of beam heating effects, fast and precise positioning of the sample in the x-ray beam, and fast acquisition of x-ray scans over a wide temperature range without the need for time-consuming re-centering and re-alignment. Furthermore, on an YBa2Cu3O7-delta crystal and a copper foil, we demonstrate a novel approach to x-ray absorption spectroscopy by monitoring the change in sample temperature as a function of incident photon energy. Finally, we illustrate the new insights that can be gained from in situ structural and thermodynamic measurements by investigating the superheated state occurring at the first-order magneto-elastic phase transition of Fe2P, a material that is of interest for magnetocaloric applications.

  7. X-ray diffraction contrast tomography (DCT) system, and an X-ray diffraction contrast tomography (DCT) method

    DEFF Research Database (Denmark)

    2012-01-01

    Source: US2012008736A An X-ray diffraction contrast tomography system (DCT) comprising a laboratory X-ray source (2), a staging device (5) rotating a polycrystalline material sample in the direct path of the X-ray beam, a first X-ray detector (6) detecting the direct X-ray beam being transmitted...

  8. Grazing Incidence X-ray Scattering and Diffraction

    Indian Academy of Sciences (India)

    ... Journals; Resonance – Journal of Science Education; Volume 19; Issue 12. Grazing Incidence X-ray Scattering and Diffraction. Jaydeep K Basu. General Article Volume 19 Issue 12 December ... Keywords. X-ray reflectivity; X-ray diffuse scattering; grazing incident diffraction; grazing incident; small angle X-ray scattering.

  9. Basic of X-ray diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Giacovazzo, C. [Bari Univ. (Italy). Dip. Geomineralogico

    1996-09-01

    The basic concepts of X-ray diffraction may be more easily understood if it is made preliminary use of a mathematical background. In these pages the authors will first define the delta function and its use for the representation of a lattice. Then the concepts of Fourier transform and convolution are given. At the end of this talk one should realize that a crystal is the convolution of the lattice with a function representing the content of the unit cell.

  10. Glancing angle synchrotron X-ray diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Cernik, R.J. [Daresbury Lab., Warrington, WA (United States)

    1996-09-01

    This paper describes in basic detail some of the techniques that can be used to study thin films and surfaces. These are all in the X-ray region and cover reflectivity, diffraction form polycrystalline films, textured films and single crystal films. Other effects such as fluorescence and diffuse scattering are mentioned but not discussed in detail. Two examples of the reflectivity from multilayers and the diffraction from iron oxide films are discussed. The advantages of the synchrotron for these studies is stressed and the experimental geometries that can be employed are described i detail. A brief bibliography is provided at the end to accompany this part of the 1996 Frascati school.

  11. Fusion bonding of Si wafers investigated by x ray diffraction

    DEFF Research Database (Denmark)

    Weichel, Steen; Grey, Francois; Rasmussen, Kurt

    2000-01-01

    The interface structure of bonded Si(001) wafers with twist angle 6.5 degrees is studied as a function of annealing temperature. An ordered structure is observed in x-ray diffraction by monitoring a satellite reflection due to the periodic modulation near the interface, which results from...

  12. X-ray diffraction with novel geometry

    Energy Technology Data Exchange (ETDEWEB)

    Prokopiou, Danae [Department of Engineering and Applied Science Cranfield University, Shrivenham Campus, Swindon (United Kingdom); Rogers, Keith, E-mail: k.d.rogers@cranfield.ac.uk [Department of Engineering and Applied Science Cranfield University, Shrivenham Campus, Swindon (United Kingdom); Evans, Paul; Godber, Simon [Imaging Science Group, School of Science and Technology, Nottingham Trent University Clifton Campus, Nottingham (United Kingdom); Shackel, James [Department of Engineering and Applied Science Cranfield University, Shrivenham Campus, Swindon (United Kingdom); Dicken, Anthony [Imaging Science Group, School of Science and Technology, Nottingham Trent University Clifton Campus, Nottingham (United Kingdom)

    2014-01-21

    An innovative geometry for high efficiency harvesting of diffracted X-rays is explored. Further to previous work where planar samples were fixed normal to the primary axis, this work extends focal construct geometry (FCG), to samples randomly oriented with respect to the incident beam. The effect of independent sample rotation around two axes upon the scattering distributions was investigated in analytical, simulation and empirical manners. It was found that, although the profile of Bragg maxima were modified when the sample was rotated, high intensity diffraction data was still acquired. Modelling produced a good match to the empirical data and it was shown that the distortions caused by sample rotation were not severe and predictable even when sample rotations were large. The implications for this are discussed.

  13. Room-temperature serial crystallography using a kinetically optimized microfluidic device for protein crystallization and on-chip X-ray diffraction

    Directory of Open Access Journals (Sweden)

    Michael Heymann

    2014-09-01

    Full Text Available An emulsion-based serial crystallographic technology has been developed, in which nanolitre-sized droplets of protein solution are encapsulated in oil and stabilized by surfactant. Once the first crystal in a drop is nucleated, the small volume generates a negative feedback mechanism that lowers the supersaturation. This mechanism is exploited to produce one crystal per drop. Diffraction data are measured, one crystal at a time, from a series of room-temperature crystals stored on an X-ray semi-transparent microfluidic chip, and a 93% complete data set is obtained by merging single diffraction frames taken from different unoriented crystals. As proof of concept, the structure of glucose isomerase was solved to 2.1 Å, demonstrating the feasibility of high-throughput serial X-ray crystallography using synchrotron radiation.

  14. X-ray diffraction imaging of material microstructures

    KAUST Repository

    Varga, Laszlo

    2016-10-20

    Various examples are provided for x-ray imaging of the microstructure of materials. In one example, a system for non-destructive material testing includes an x-ray source configured to generate a beam spot on a test item; a grid detector configured to receive x- rays diffracted from the test object; and a computing device configured to determine a microstructure image based at least in part upon a diffraction pattern of the x-rays diffracted from the test object. In another example, a method for determining a microstructure of a material includes illuminating a beam spot on the material with a beam of incident x-rays; detecting, with a grid detector, x-rays diffracted from the material; and determining, by a computing device, a microstructure image based at least in part upon a diffraction pattern of the x-rays diffracted from the material.

  15. X-ray photoelectron spectroscopy, high-resolution X-ray diffraction ...

    Indian Academy of Sciences (India)

    Powder X-ray diffraction studies were carried out on doped lithium niobate for phase identification. High-resolution X-ray diffraction technique was used to study the crystalline quality through full-width at half-maximum values. The refractive index values are more for doped samples than for pure sample as determined by ...

  16. Variable temperature and high-pressure crystal chemistry of perovskite formamidinium lead iodide: a single crystal X-ray diffraction and computational study.

    Science.gov (United States)

    Sun, Shijing; Deng, Zeyu; Wu, Yue; Wei, Fengxia; Halis Isikgor, Furkan; Brivio, Federico; Gaultois, Michael W; Ouyang, Jianyong; Bristowe, Paul D; Cheetham, Anthony K; Kieslich, Gregor

    2017-07-04

    We investigate the variable temperature (100-450 K) and high-pressure (p = ambient - 0.74 GPa) crystal chemistry of the black perovskite formamidinium lead iodide, [(NH2)2CH]PbI3, using single crystal X-ray diffraction. In both cases we find a phase transition to a tetragonal phase. Our experimental results are combined with first principles calculations, providing information about the electronic properties of [(NH2)2CH]PbI3 as well as the most probable orientation of the [(NH2)2CH](+) cations.

  17. Serial femtosecond X-ray diffraction of enveloped virus microcrystals

    Directory of Open Access Journals (Sweden)

    Robert M. Lawrence

    2015-07-01

    Full Text Available Serial femtosecond crystallography (SFX using X-ray free-electron lasers has produced high-resolution, room temperature, time-resolved protein structures. We report preliminary SFX of Sindbis virus, an enveloped icosahedral RNA virus with ∼700 Å diameter. Microcrystals delivered in viscous agarose medium diffracted to ∼40 Å resolution. Small-angle diffuse X-ray scattering overlaid Bragg peaks and analysis suggests this results from molecular transforms of individual particles. Viral proteins undergo structural changes during entry and infection, which could, in principle, be studied with SFX. This is an important step toward determining room temperature structures from virus microcrystals that may enable time-resolved studies of enveloped viruses.

  18. DEVELOPMENT OF NEW INSTRUMENTATION AND TECHNIQUES IN X-RAY DIFFRACTION.

    Science.gov (United States)

    This Project had as its original objectives the development of new instrumentation and techniques in x-ray diffraction and the improvement of...recent years emphasis was shifted to, or was concentrated on, the development of low-temperature x-ray diffraction methods and on studies carried out

  19. A Furnace for Diffraction Studies using Synchrotron X-Ray Radiation

    DEFF Research Database (Denmark)

    Buras, B.; Lebech, Bente; Kofoed, W.

    1984-01-01

    A furnace for diffraction studies using synchrotron X-ray radiation is described. The furnace can be operated between ambient temperature and 1 800 °C with a temperature stability better than 5 °C for temperatures above 300 °C. Kapton windows allow almost 360° access for the X-ray beam...

  20. High-resolution X-ray diffraction studies of multilayers

    DEFF Research Database (Denmark)

    Christensen, Finn Erland; Hornstrup, Allan; Schnopper, H. W.

    1988-01-01

    High-resolution X-ray diffraction studies of the perfection of state-of-the-art multilayers are presented. Data were obtained using a triple-axis perfect-crystal X-ray diffractometer. Measurements reveal large-scale figure errors in the substrate. A high-resolution triple-axis set up is required...

  1. In-situ X-ray diffraction reveals the degradation of crystalline CH3NH3PbI3 by water-molecule collisions at room temperature

    Science.gov (United States)

    Hada, Masaki; Hasegawa, Yoichi; Nagaoka, Ryota; Miyake, Tomoya; Abdullaev, Ulugbek; Ota, Hiromi; Nishikawa, Takeshi; Yamashita, Yoshifumi; Hayashi, Yasuhiko

    2018-02-01

    We have developed a vacuum-compatible chamber for in-situ X-ray diffraction (XRD) studies and have used it to characterize the changing crystal structure of an inorganic–organic hybrid perovskite material, CH3NH3PbI3 (MAPbI3), during interactions with water vapor at room temperature. In the XRD spectra, we have observed the degradation of MAPbI3 and the creation of MAPbI3 hydrates, which follow simple rate equations. The time constant for the degradation of MAPbI3 during accelerated aging suggests that multiple collisions of water molecules with the MAPbI3 crystal trigger the degradation of the crystal.

  2. Thin film characterisation by advanced X-ray diffraction techniques

    Energy Technology Data Exchange (ETDEWEB)

    Cappuccio, G.; Terranova, M.L. [eds.] [INFN, Laboratori Nazionali di Frascati, Rome (Italy)

    1996-09-01

    This report described the papers presented at the 5. School on X-ray diffraction from polycrystalline materials held at Frascati (Rome) in 2-5 October 1996. A separate abstract was prepared for each of the papers.

  3. Theory of time-resolved inelastic x-ray diffraction

    DEFF Research Database (Denmark)

    Lorenz, Ulf; Møller, Klaus Braagaard; Henriksen, Niels Engholm

    2010-01-01

    Starting from a general theory of time-resolved x-ray scattering, we derive a convenient expression for the diffraction signal based on a careful analysis of the relevant inelastic scattering processes. We demonstrate that the resulting inelastic limit applies to a wider variety of experimental...... conditions than similar, previously derived formulas, and it directly allows the application of selection rules when interpreting diffraction signals. Furthermore, we present a simple extension to systems simultaneously illuminated by x rays and a laser beam....

  4. X-ray optics the diffraction of X-rays by finite and imperfect crystals

    CERN Document Server

    Wilson, Arthur J C

    1949-01-01

    This fascinating text contains a detailed treatise on the use of X-Ray optics in the taxonomy of minerals and gem stones. An interesting and informative book on the subject, X-Ray Optics - The Diffraction of X-Rays by Finite and Imperfect Crystals is a must-have for anyone with an interest the study of crystals and constitutes a great addition to any gemmological collection. Arthur James Cochran Wilson (28 November 1914 - 1 July 1995) was a Canadian crystallographer, most famous for his contributions to X-ray crystallography and elected as a Fellow of the Royal Society in 1963. This book has been elected for republication now due to its immense educational value, and is proudly republished here complete with a new introduction to the subject.

  5. Combined resistive and laser heating technique for in situ radial X-ray diffraction in the diamond anvil cell at high pressure and temperature

    Energy Technology Data Exchange (ETDEWEB)

    Miyagi, Lowell [Department of Geology and Geophysics, University of Utah, Salt Lake City, Utah 84112 (United States); Department of Earth Sciences, Montana State University, Bozeman, Montana 59717 (United States); Kanitpanyacharoen, Waruntorn; Kaercher, Pamela; Wenk, Hans-Rudolf; Alarcon, Eloisa Zepeda [Department of Earth and Planetary Science, University of California, Berkeley, California 94720 (United States); Raju, Selva Vennila [Advanced Light Source, Lawrence Berkeley Laboratory, Berkeley, California 94720 (United States); HiPSEC, Department of Physics, University of Nevada, Las Vegas, Nevada 89154 (United States); Knight, Jason; MacDowell, Alastair [Advanced Light Source, Lawrence Berkeley Laboratory, Berkeley, California 94720 (United States); Williams, Quentin [Department of Earth and Planetary Science, University of California, Santa Cruz, California 95064 (United States)

    2013-02-15

    To extend the range of high-temperature, high-pressure studies within the diamond anvil cell, a Liermann-type diamond anvil cell with radial diffraction geometry (rDAC) was redesigned and developed for synchrotron X-ray diffraction experiments at beamline 12.2.2 of the Advanced Light Source. The rDAC, equipped with graphite heating arrays, allows simultaneous resistive and laser heating while the material is subjected to high pressure. The goals are both to extend the temperature range of external (resistive) heating and to produce environments with lower temperature gradients in a simultaneously resistive- and laser-heated rDAC. Three different geomaterials were used as pilot samples to calibrate and optimize conditions for combined resistive and laser heating. For example, in Run1, FeO was loaded in a boron-mica gasket and compressed to 11 GPa then gradually resistively heated to 1007 K (1073 K at the diamond side). The laser heating was further applied to FeO to raise temperature to 2273 K. In Run2, Fe-Ni alloy was compressed to 18 GPa and resistively heated to 1785 K (1973 K at the diamond side). The combined resistive and laser heating was successfully performed again on (Mg{sub 0.9}Fe{sub 0.1})O in Run3. In this instance, the sample was loaded in a boron-kapton gasket, compressed to 29 GPa, resistive-heated up to 1007 K (1073 K at the diamond side), and further simultaneously laser-heated to achieve a temperature in excess of 2273 K at the sample position. Diffraction patterns obtained from the experiments were deconvoluted using the Rietveld method and quantified for lattice preferred orientation of each material under extreme conditions and during phase transformation.

  6. Combined resistive and laser heating technique for in situ radial X-ray diffraction in the diamond anvil cell at high pressure and temperature.

    Science.gov (United States)

    Miyagi, Lowell; Kanitpanyacharoen, Waruntorn; Raju, Selva Vennila; Kaercher, Pamela; Knight, Jason; MacDowell, Alastair; Wenk, Hans-Rudolf; Williams, Quentin; Alarcon, Eloisa Zepeda

    2013-02-01

    To extend the range of high-temperature, high-pressure studies within the diamond anvil cell, a Liermann-type diamond anvil cell with radial diffraction geometry (rDAC) was redesigned and developed for synchrotron X-ray diffraction experiments at beamline 12.2.2 of the Advanced Light Source. The rDAC, equipped with graphite heating arrays, allows simultaneous resistive and laser heating while the material is subjected to high pressure. The goals are both to extend the temperature range of external (resistive) heating and to produce environments with lower temperature gradients in a simultaneously resistive- and laser-heated rDAC. Three different geomaterials were used as pilot samples to calibrate and optimize conditions for combined resistive and laser heating. For example, in Run#1, FeO was loaded in a boron-mica gasket and compressed to 11 GPa then gradually resistively heated to 1007 K (1073 K at the diamond side). The laser heating was further applied to FeO to raise temperature to 2273 K. In Run#2, Fe-Ni alloy was compressed to 18 GPa and resistively heated to 1785 K (1973 K at the diamond side). The combined resistive and laser heating was successfully performed again on (Mg0.9Fe0.1)O in Run#3. In this instance, the sample was loaded in a boron-kapton gasket, compressed to 29 GPa, resistive-heated up to 1007 K (1073 K at the diamond side), and further simultaneously laser-heated to achieve a temperature in excess of 2273 K at the sample position. Diffraction patterns obtained from the experiments were deconvoluted using the Rietveld method and quantified for lattice preferred orientation of each material under extreme conditions and during phase transformation.

  7. X-ray characterization by energy-resolved powder diffraction

    Directory of Open Access Journals (Sweden)

    G. Cheung

    2016-08-01

    Full Text Available A method for single-shot, nondestructive characterization of broadband x-ray beams, based on energy-resolved powder diffraction, is described. Monte-Carlo simulations are used to simulate data for x-ray beams in the keV range with parameters similar to those generated by betatron oscillations in a laser-driven plasma accelerator. The retrieved x-ray spectra are found to be in excellent agreement with those of the input beams for realistic numbers of incident photons. It is demonstrated that the angular divergence of the x rays can be deduced from the deviation of the detected photons from the Debye-Scherrer rings which would be produced by a parallel beam. It is shown that the angular divergence can be measured as a function of the photon energy, yielding the angularly resolved spectrum of the input x-ray beam.

  8. High resolution x-ray diffraction study of the substrate temperature and thickness dependent microstructure of reactively sputtered epitaxial ZnO films

    KAUST Repository

    Singh, Devendra

    2017-08-24

    Epitaxial ZnO films were grown on c-sapphire by reactive sputtering of zinc target in Ar-O2 mixture. High resolution X-ray diffraction measurements were carried out to obtain lateral and vertical coherence lengths, crystallite tilt and twist, micro-strain and densities of screw and edge dislocations in epilayers of different thickness (25 - 200 nm) and those grown at different temperatures (100 - 500 °C). phgr-scans indicate epitaxial growth in all the cases, although epilayers grown at lower substrate temperatures (100 °C and 200 °C) and those of smaller thickness (25 nm and 50 nm) display inferior microstructural parameters. This is attributed to the dominant presence of initially grown strained 2D layer and subsequent transition to an energetically favorable mode. With increase in substrate temperature, the transition shifts to lower thickness and growth takes place through the formation of 2D platelets with intermediate strain, over which 3D islands grow. Consequently, 100 nm thick epilayers grown at 300 °C display the best microstructural parameters (micro-strain ~1.2 x 10-3, screw and edge dislocation densities ~1.5 x 1010 cm-2 and ~2.3 x 1011 cm-2, respectively). A marginal degradation of microstructural parameters is seen in epilayers grown at higher substrate temperatures, due to the dominance of 3D hillock type growth.

  9. Enhancement of coherent X-ray diffraction from nanocrystals by introduction of X-ray optics.

    Science.gov (United States)

    Robinson, Ian; Pfeiffer, Franz; Vartanyants, Ivan; Sun, Yugang; Xia, Younan

    2003-09-22

    Coherent X-ray Diffraction is applied to investigate the structure of individual nanocrystalline silver particles in the 100nm size range. In order to enhance the available signal, Kirkpatrick-Baez focusing optics have been introduced in the 34-ID-C beamline at APS. Concerns about the preservation of coherence under these circumstances are addressed through experiment and by calculations.

  10. Characterization of Metalloproteins and Biomaterials by X-ray Absorption Spectroscopy and X-ray Diffraction

    DEFF Research Database (Denmark)

    Frankær, Christian Grundahl

    This thesis presents thework on combining complementary X-rays techniques for studying the structures of proteins and other biomaterials, and consists of three different projects: (i) Characterization of protein powders with X-ray powder diffraction (XRPD). (ii) The combination of X-ray crystallo......This thesis presents thework on combining complementary X-rays techniques for studying the structures of proteins and other biomaterials, and consists of three different projects: (i) Characterization of protein powders with X-ray powder diffraction (XRPD). (ii) The combination of X......, nickel and copper, and their XRD crystal structures were solved to 1.90 Å, 1.50 Å and 1.45 Å resolution, respectively. As the affinity to iron is low, iron insulin crystals were grown in presence of small amounts of zinc. The two metal sites in the XRD structure thus contained respectively one Fe2......+ and one Zn2+ ion, with respectively tetrahedral and octahedral coordination geometry. The metal sites in nickel and copper insulin were studied by XAS. Coordination distances were refined from EXAFS showing a very regular octahedral coordination of Ni2+, which was further verified by calculated XANES...

  11. Spectroscopic imaging, diffraction, and holography with x-ray photoemission

    Energy Technology Data Exchange (ETDEWEB)

    1992-02-01

    X-ray probes are capable of determining the spatial structure of an atom in a specific chemical state, over length scales from about a micron all the way down to atomic resolution. Examples of these probes include photoemission microscopy, energy-dependent photoemission diffraction, photoelectron holography, and X-ray absorption microspectroscopy. Although the method of image formation, chemical-state sensitivity, and length scales can be very different, these X-ray techniques share a common goal of combining a capability for structure determination with chemical-state specificity. This workshop will address recent advances in holographic, diffraction, and direct imaging techniques using X-ray photoemission on both theoretical and experimental fronts. A particular emphasis will be on novel structure determinations with atomic resolution using photoelectrons.

  12. X-ray diffraction microtomography using synchrotron radiation

    CERN Document Server

    Barroso, R C; Jesus, E F O; Oliveira, L F

    2001-01-01

    The X-ray diffraction computed tomography technique is based on the interference phenomena of the coherent scatter. For low-momentum transfer, it is most probable that the scattering interaction will be coherent. A selective discrimination of a given element in a scanned specimen can be realized by fixing the Bragg angle which produces an interference peak and then, to carry out the computed tomography in the standard mode. The image reconstructed exalts the presence of this element with respect to other ones in a sample. This work reports the feasibility of a non-destructive synchrotron radiation X-ray diffraction imaging technique. This research was performed at the X-ray Diffraction beam line of the National Synchrotron Light Laboratory (LNLS) in Brazil. The coherent scattering properties of different tissue and bone substitute materials were evaluated. Furthermore, diffraction patterns of some polycrystalline solids were studied due to industrial and environmental human exposure to these metals. The obtai...

  13. Calculated x-ray powder diffraction patterns of plutonium

    Energy Technology Data Exchange (ETDEWEB)

    Roof, R.B.

    1977-10-01

    The X-ray powder diffraction patterns of the six phases of plutonium were calculated for Cu K..cap alpha../sub 1/ (lambda = 1.540598 A.) The results listed are 2 theta, sin/sup 2/ theta, d values, integrated intensities, and diffraction indices hkl.

  14. X-ray diffraction crystallography. Introduction, examples and solved problems

    Energy Technology Data Exchange (ETDEWEB)

    Waseda, Yoshio; Shinoda, Kozo [Tohoku Univ., Sendai (Japan). Inst. of Multidisciplinary Research for Advanced Materials; Matsubara, Eiichiro [Kyoto Univ. (Japan). Dept. of Materials Science and Engineering

    2011-07-01

    X-ray diffraction crystallography for powder samples is a well-established and widely used method. It is applied to materials characterization to reveal the atomic scale structure of various substances in a variety of states. The book deals with fundamental properties of X-rays, geometry analysis of crystals, X-ray scattering and diffraction in polycrystalline samples and its application to the determination of the crystal structure. The reciprocal lattice and integrated diffraction intensity from crystals and symmetry analysis of crystals are explained. To learn the method of X-ray diffraction crystallography well and to be able to cope with the given subject, a certain number of exercises is presented in the book to calculate specific values for typical examples. This is particularly important for beginners in X-ray diffraction crystallography. One aim of this book is to offer guidance to solving the problems of 90 typical substances. For further convenience, 100 supplementary exercises are also provided with solutions. Some essential points with basic equations are summarized in each chapter, together with some relevant physical constants and the atomic scattering factors of the elements. (orig.)

  15. X-ray diffraction study of directionally grown perylene crystallites

    DEFF Research Database (Denmark)

    Breiby, Dag W.; Lemke, H. T.; Hammershøj, P.

    2008-01-01

    Using grazing incidence X-ray diffraction, perylene crystallites grown on thin highly oriented poly(tetrafluoroethylene) (PTFE) films on silicon substrates have been investigated. All the perylene crystallites are found to orient with the ab plane of the monoclinic unit cell parallel to the subst......Using grazing incidence X-ray diffraction, perylene crystallites grown on thin highly oriented poly(tetrafluoroethylene) (PTFE) films on silicon substrates have been investigated. All the perylene crystallites are found to orient with the ab plane of the monoclinic unit cell parallel...

  16. A study on the phase transformation of the nanosized hydroxyapatite synthesized by hydrolysis using in situ high temperature X-ray diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Shih, W.-J. [Department of Materials Science and Engineering, National Cheng Kung University, 1 Ta-Hsueh Road, Tainan, 70101, Taiwan (China); Wang, J.-W. [Department of Enviromental and Safety Engineering, Chung Hwa College of Medical Technology, 89 Wen-Hua 1st St., Rende Shiang, Tainan, 71703, Taiwan (China); Wang, M.-C. [Department of Materials Science and Engineering, National United University, 1 Lien-Da, Kung-Ching Li, Miao Li 360, Taiwan (China)]. E-mail: mcwang@nuu.edu.tw; Hon, M.-H. [Department of Materials Science and Engineering, National Cheng Kung University, 1 Ta-Hsueh Road, Tainan, 70101, Taiwan (China); Dayeh University, 112 Shan-Jiau Road, Da-Tsuen, Changhua 515, Taiwan (China)

    2006-09-15

    The biodegradable hydroxyapatite (HA) was synthesized by hydrolysis and characterized using high temperature X-ray diffraction (HT-XRD), differential thermal analysis and thermogravimetry (DTA/TG), and scanning electron microscopy (SEM). The in situ phase transformation of the HA synthesized from CaHPO{sub 4}.2H{sub 2}O (DCPD) and CaCO{sub 3} with a Ca / P = 1.5 in 2.5 M NaOH{sub (aq)} at 75 deg. C for 1 h was investigated by HT-XRD between 25 and 1500 deg. C. The HA was crystallized at 600 deg. C and maintained as the major phase until 1400 deg. C. The HA steadily transformed to the {alpha}-tricalcium phosphate ({alpha}-TCP) which became the major phosphate phase at 1500 deg. C. At 700 deg. C, the minor CaO phase appeared and vanished at 1300 deg. C. The Na{sup +} impurity from the hydrolysis process was responsible for the formation of the NaCaPO{sub 4} phase, which appeared above 800 deg. C and disappeared at 1200 deg. C.

  17. Optical properties of X-rays--dynamical diffraction.

    Science.gov (United States)

    Authier, André

    2012-01-01

    The first attempts at measuring the optical properties of X-rays such as refraction, reflection and diffraction are described. The main ideas forming the basis of Ewald's thesis in 1912 are then summarized. The first extension of Ewald's thesis to the X-ray case is the introduction of the reciprocal lattice. In the next step, the principles of the three versions of the dynamical theory of diffraction, by Darwin, Ewald and Laue, are given. It is shown how the comparison of the dynamical and geometrical theories of diffraction led Darwin to propose his extinction theory. The main optical properties of X-ray wavefields at the Bragg incidence are then reviewed: Pendellösung, shift of the Bragg peak, fine structure of Kossel lines, standing waves, anomalous absorption, paths of wavefields inside the crystal, Borrmann fan and double refraction. Lastly, some of the modern applications of the dynamical theory are briefly outlined: X-ray topography, location of adsorbed atoms at crystal surfaces, optical devices for synchrotron radiation and X-ray interferometry.

  18. X-Ray diffraction and scanning electron microscopy-energy dispersive spectroscopic analysis of ceramõmetal interface at different firing temperatures

    Directory of Open Access Journals (Sweden)

    Monika Saini

    2010-01-01

    Full Text Available Objective: Porcelain chipping from porcelain fused to metal restoration has been Achilles heel till date. There has been advent of newer ceramics in past but but none of them has been a panacea for Porcelain fracture. An optimal firing is thus essential for the clinical success of the porcelain-fused to metal restoration. The aim of the present study was to evaluate ceramo-metal interface at different firing temperature using XRD and SEM-EDS analysis. Clinical implication of the study was to predict the optimal firing temperature at which porcelain should be fused with metal in order to possibly prevent the occasional failure of the porcelain fused to metal restorations. Materials and Methods: To meet the above-mentioned goal, porcelain was fused to metal at different firing temperatures (930-990°C in vacuum. The microstructural observations of interface between porcelain and metal were evaluated using X-ray diffraction and scanning electron microscopy with energy dispersive spectroscopy. Results: Based on the experimental investigation of the interaction zone of porcelain fused to metal samples, it was observed that as the firing temperature was increased, the pores became less in number as well as the size of the pores decreased at the porcelain/metal interface upto 975°C but increased in size at 990°C. The least number of pores with least diameter were found in samples fired at 975°C. Several oxides like Cr 2 O 3 , NiO, and Al 2 O 3 and intermetallic compounds (CrSi 2 , AlNi 3 were also formed in the interaction zone. Conclusions : It is suggested that the presence of pores may trigger the crack propagation along the interface, causing the failure of the porcelain fused to metal restoration during masticatory action.

  19. Picosecond X-ray diffraction from laser-irradiated crystals

    Energy Technology Data Exchange (ETDEWEB)

    Hironaka, Yoichiro; Yazaki, Akio; Kishimura, Hiroaki; Nakamura, Kazutaka G.; Kondo, Ken-ichi

    2002-09-30

    We performed time-resolved X-ray diffraction for laser-irradiated Si(1 1 1) single crystal. A tabletop TW laser system was used for the generation of the ultra-short pulsed X-rays. We discussed the generation of laser induced ultra-short pulsed X-rays concerning about broadening of diffracted signal due to the electron scattering in the pre-plasma. We measured laser induced acoustic wave propagation inside of Si crystal by the laser irradiation, and the maximum lattice strain of -1.05% was measured at the irradiation power density of 4.7x10{sup 9} W/cm{sup 2} with picosecond time resolution. Stress distribution analysis on the observed data under laser irradiation is also dised.

  20. High resolution X-ray diffraction studies on unirradiated and ...

    Indian Academy of Sciences (India)

    High-resolution X-ray diffraction technique, employing a three-crystal monochromator–collimator ... observed by high-resolution electron microscopy in both ..... 1988 Nucl. Instrum. Meth. B34 228. Kato N 1992 J. Acta Crystallogr. A48 834. Kaur B, Bhat M, Licci F, Kumar R, Kotru P N and Bamzai K K. 2004 Nucl. Instrum. Meth ...

  1. Silicon supported lipid-DNA thin film structures at varying temperature studied by energy dispersive X-ray diffraction and neutron reflectivity.

    Science.gov (United States)

    Domenici, F; Castellano, C; Dell'Unto, F; Albinati, A; Congiu, A

    2011-11-01

    Non-viral gene transfection by means of lipid-based nanosystems, such as solid supported lipid assemblies, is often limited due to their lack of stability and the consequent loss of efficiency. Therefore not only a detailed thermo-lyotropic study of these DNA-lipid complexes is necessary to understand their interaction mechanisms, but it can also be considered as a first step in conceiving and developing new transfection biosystems. The aim of our study is a structural characterization of 1,2-dioleoyl-sn-glycero-3-phosphatidylcholine (DOPC)-dimethyl-dioctadecyl-ammonium bromide (DDAB)-DNA complex at varying temperature using the energy dispersive X-ray diffraction (EDXD) and neutron reflectivity (NR) techniques. We have shown the formation of a novel thermo-lyotropic structure of DOPC/DDAB thin film self-organized in multi-lamellar planes on (100)-oriented silicon support by spin coating, thus enlightening its ability to include DNA strands. Our NR measurements indicate that the DOPC/DDAB/DNA complex forms temperature-dependent structures. At 65°C and relative humidity of 100% DNA fragments are buried between single lamellar leaflets constituting the hydrocarbon core of the lipid bilayers. This finding supports the consistency of the hydrophobic interaction model, which implies that the coupling between lipid tails and hypo-hydrated DNA single strands could be the driving force of DNA-lipid complexation. Upon cooling to 25°C, EDXD analysis points out that full-hydrated DOPC-DDAB-DNA can switch in a different metastable complex supposed to be driven by lipid heads-DNA electrostatic interaction. Thermotropic response analysis also clarifies that DOPC has a pivotal role in promoting the formation of our observed thermophylic silicon supported lipids-DNA assembly. Copyright © 2011 Elsevier B.V. All rights reserved.

  2. Simulating X-ray diffraction of textured films

    DEFF Research Database (Denmark)

    Breiby, Dag W.; Bunk, Oliver; Andreasen, Jens Wenzel

    2008-01-01

    Computationally efficient simulations of grazing-incidence X-ray diffraction (GIXD) are discussed, with particular attention given to textured thin polycrystalline films on supporting substrates. A computer program has been developed for simulating scattering from thin films exhibiting varying...... from the totally substrate-reflected beam ( two-beam approximation) and refraction effects are also included in the program, together with the geometrical intensity corrections associated with GIXD measurements. To achieve 'user friendliness' for scientists less familiar with diffraction...

  3. A novel high-temperature furnace for combined in situ synchrotron X-ray diffraction and infrared thermal imaging to investigate the effects of thermal gradients upon the structure of ceramic materials.

    Science.gov (United States)

    Robinson, James B; Brown, Leon D; Jervis, Rhodri; Taiwo, Oluwadamilola O; Millichamp, Jason; Mason, Thomas J; Neville, Tobias P; Eastwood, David S; Reinhard, Christina; Lee, Peter D; Brett, Daniel J L; Shearing, Paul R

    2014-09-01

    A new technique combining in situ X-ray diffraction using synchrotron radiation and infrared thermal imaging is reported. The technique enables the application, generation and measurement of significant thermal gradients, and furthermore allows the direct spatial correlation of thermal and crystallographic measurements. The design and implementation of a novel furnace enabling the simultaneous thermal and X-ray measurements is described. The technique is expected to have wide applicability in material science and engineering; here it has been applied to the study of solid oxide fuel cells at high temperature.

  4. Spectral feature variations in x-ray diffraction imaging systems

    Science.gov (United States)

    Wolter, Scott D.; Greenberg, Joel A.

    2016-05-01

    Materials with different atomic or molecular structures give rise to unique scatter spectra when measured by X-ray diffraction. The details of these spectra, though, can vary based on both intrinsic (e.g., degree of crystallinity or doping) and extrinsic (e.g., pressure or temperature) conditions. While this sensitivity is useful for detailed characterizations of the material properties, these dependences make it difficult to perform more general classification tasks, such as explosives threat detection in aviation security. A number of challenges, therefore, currently exist for reliable substance detection including the similarity in spectral features among some categories of materials combined with spectral feature variations from materials processing and environmental factors. These factors complicate the creation of a material dictionary and the implementation of conventional classification and detection algorithms. Herein, we report on two prominent factors that lead to variations in spectral features: crystalline texture and temperature variations. Spectral feature comparisons between materials categories will be described for solid metallic sheet, aqueous liquids, polymer sheet, and metallic, organic, and inorganic powder specimens. While liquids are largely immune to texture effects, they are susceptible to temperature changes that can modify their density or produce phase changes. We will describe in situ temperature-dependent measurement of aqueous-based commercial goods in the temperature range of -20°C to 35°C.

  5. X-ray diffraction and scanning electron microscopy of galvannealed coatings on steel.

    Science.gov (United States)

    Schmid, P; Uran, K; Macherey, F; Ebert, M; Ullrich, H-J; Sommer, D; Friedel, F

    2009-04-01

    The formation of Fe-Zn intermetallic compounds, as relevant in the commercial product galvannealed steel sheet, was investigated by scanning electron microscopy and different methods of X-ray diffraction. A scanning electron microscope with high resolution was applied to investigate the layers of the galvannealed coating and its topography. Grazing incidence X-ray diffraction (GID) was preferred over conventional Bragg-Brentano geometry for analysing thin crystalline layers because of its lower incidence angle alpha and its lower depth of information. Furthermore, in situ experiments at an environmental scanning electron microscope (ESEM) with an internal heating plate and at an X-ray diffractometer equipped with a high-temperature chamber were carried out. Thus, it was possible to investigate the phase evolution during heat treatment by X-ray diffraction and to display the growth of the zeta crystals in the ESEM.

  6. Determination of organic crystal structures by X ray powder diffraction

    CERN Document Server

    McBride, L

    2000-01-01

    The crystal structure of Ibuprofen has been solved from synchrotron X-ray powder diffraction data using a genetic algorithm (GA). The performance of the GA is improved by incorporating prior chemical information in the form of hard limits on the values that can be taken by the flexible torsion angles within the molecule. Powder X-ray diffraction data were collected for the anti-convulsant compounds remacemide, remacemide nitrate and remacemide acetate at 130 K on BM 16 at the X-ray European Synchrotron Radiation Facility (ESRF) at Grenoble. High quality crystal structures were obtained using data collected to a resolution of typically 1.5 A. The structure determinations were performed using a simulated annealing (SA) method and constrained Rietveld refinements for the structures converged to chi sup 2 values of 1.64, 1.84 and 1.76 for the free base, nitrate and acetate respectively. The previously unknown crystal structure of the drug famotidine Form B has been solved using X-ray powder diffraction data colle...

  7. MSL Chemistry and Mineralogy X-Ray Diffraction X-Ray Fluorescence (CheMin) Instrument

    Science.gov (United States)

    Zimmerman, Wayne; Blake, Dave; Harris, William; Morookian, John Michael; Randall, Dave; Reder, Leonard J.; Sarrazin, Phillipe

    2013-01-01

    This paper provides an overview of the Mars Science Laboratory (MSL) Chemistry and Mineralogy Xray Diffraction (XRD), X-ray Fluorescence (XRF) (CheMin) Instrument, an element of the landed Curiosity rover payload, which landed on Mars in August of 2012. The scientific goal of the MSL mission is to explore and quantitatively assess regions in Gale Crater as a potential habitat for life - past or present. The CheMin instrument will receive Martian rock and soil samples from the MSL Sample Acquisition/Sample Processing and Handling (SA/SPaH) system, and process it utilizing X-Ray spectroscopy methods to determine mineral composition. The Chemin instrument will analyze Martian soil and rocks to enable scientists to investigate geophysical processes occurring on Mars. The CheMin science objectives and proposed surface operations are described along with the CheMin hardware with an emphasis on the system engineering challenges associated with developing such a complex instrument.

  8. X-ray magnetic diffraction of ferromagnets with synchrotron radiation

    CERN Document Server

    Ito, M

    2002-01-01

    X-ray magnetic diffraction experiment of ferromagnets that utilizes elliptically polarized synchrotron radiation is presented. First we have reviewed shortly historical backgrounds and theoretical aspects of the experiment. We have presented how the magnetic form factors are measured and are separated into the spin-moment component and the orbital-moment component in this experiment. Peculiar features of the polarization factor of this experiment have been explained. We have introduced two examples of the experiment. One is the measurement of the spin-magnetic form factor of SmAl sub 2 with white X-rays from a bending magnet at the Photon Factory. The other is the measurement of the orbital-magnetic form factor of Holmium Iron Garnets with monochromatic X-rays from an undulator at the SPring-8. Finally we summarize the article and show some future prospects of this experiment. (author)

  9. Instrument and method for X-ray diffraction, fluorescence, and crystal texture analysis without sample preparation

    Science.gov (United States)

    Gendreau, Keith (Inventor); Martins, Jose Vanderlei (Inventor); Arzoumanian, Zaven (Inventor)

    2010-01-01

    An X-ray diffraction and X-ray fluorescence instrument for analyzing samples having no sample preparation includes a X-ray source configured to output a collimated X-ray beam comprising a continuum spectrum of X-rays to a predetermined coordinate and a photon-counting X-ray imaging spectrometer disposed to receive X-rays output from an unprepared sample disposed at the predetermined coordinate upon exposure of the unprepared sample to the collimated X-ray beam. The X-ray source and the photon-counting X-ray imaging spectrometer are arranged in a reflection geometry relative to the predetermined coordinate.

  10. Wavefront aberrations of x-ray dynamical diffraction beams.

    Science.gov (United States)

    Liao, Keliang; Hong, Youli; Sheng, Weifan

    2014-10-01

    The effects of dynamical diffraction in x-ray diffractive optics with large numerical aperture render the wavefront aberrations difficult to describe using the aberration polynomials, yet knowledge of them plays an important role in a vast variety of scientific problems ranging from optical testing to adaptive optics. Although the diffraction theory of optical aberrations was established decades ago, its application in the area of x-ray dynamical diffraction theory (DDT) is still lacking. Here, we conduct a theoretical study on the aberration properties of x-ray dynamical diffraction beams. By treating the modulus of the complex envelope as the amplitude weight function in the orthogonalization procedure, we generalize the nonrecursive matrix method for the determination of orthonormal aberration polynomials, wherein Zernike DDT and Legendre DDT polynomials are proposed. As an example, we investigate the aberration evolution inside a tilted multilayer Laue lens. The corresponding Legendre DDT polynomials are obtained numerically, which represent balanced aberrations yielding minimum variance of the classical aberrations of an anamorphic optical system. The balancing of classical aberrations and their standard deviations are discussed. We also present the Strehl ratio of the primary and secondary balanced aberrations.

  11. DETERMINATION OF REACTION KINETICS USING ONLINE X-RAY DIFFRACTION

    Directory of Open Access Journals (Sweden)

    Elida Purba

    2010-06-01

    Full Text Available X-ray diffraction (XRD is a powerful technique for the study of polymorphism and polymorphic phase transformations. Monitoring of phase transformation directly has been very limited to-date. The XRD system used in this study was used to determine the rate of transformation of pure glutamic acid a form to b form in a solution mediated phase. On every run starting from the pure a form, the transformation process was monitored continuously at fixed temperature, and separate experiments were performed as a function of temperature. The operating temperature was varied from 36 to 57 °C with 10% w/w solid concentration. Data were taken every 200 seconds until the transformation was completed. This paper is concerned with a study of the transformation of the alpha (a form of L-glutamic acid (L-GA to the beta (b form in order to determine the kinetic reaction. The rate constant (k, activation energy (Ea and pre-exponential factor (A were obtained. Sensitivity tests were also carried out to examine minimum detection limit when both a and b present in the mixture. In addition, effect of particle size on XRD patterns was also determined. The results show that XRD gives useful information to observe polymorphism for pharmaceutical industry.     Keywords: XRD, polymorphism, glutamic acid, reaction kinetics

  12. Thermal expansion in UO 2 determined by high-energy X-ray diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Guthrie, M.; Benmore, C. J.; Skinner, L. B.; Alderman, O. L. G.; Weber, J. K. R.; Parise, J. B.; Williamson, M.

    2016-10-01

    Here we present crystallographic analyses of high-energy X-ray diffraction data on polycrystalline UO2 up to the melting temperature. The Rietveld refinements of our X-ray data are in agreement with previous measurements, but are systematically located around the upper bound of their uncertainty, indicating a slightly steeper trend of thermal expansion compared to established values. This observation is consistent with recent first principles calculations.

  13. Spatiotemporal response of crystals in x-ray Bragg diffraction

    Science.gov (United States)

    Shvyd'ko, Yuri; Lindberg, Ryan

    2012-10-01

    The spatiotemporal response of crystals in x-ray Bragg diffraction resulting from excitation by an ultrashort, laterally confined x-ray pulse is studied theoretically. The theory presents an extension of the analysis in symmetric reflection geometry [R. R. Lindberg and Y. V. Shvyd’ko, Phys. Rev. ST Accel. Beams 15, 050706 (2012)PRABFM1098-440210.1103/PhysRevSTAB.15.050706] to the generic case, which includes Bragg diffraction both in reflection (Bragg) and transmission (Laue) asymmetric scattering geometries. The spatiotemporal response is presented as a product of a crystal-intrinsic plane-wave spatiotemporal response function and an envelope function defined by the crystal-independent transverse profile of the incident beam and the scattering geometry. The diffracted wave fields exhibit amplitude modulation perpendicular to the propagation direction due to both angular dispersion and the dispersion due to Bragg’s law. The characteristic measure of the spatiotemporal response is expressed in terms of a few parameters: the extinction length, crystal thickness, Bragg angle, asymmetry angle, and the speed of light. Applications to self-seeding of hard x-ray free-electron lasers are discussed, with particular emphasis on the relative advantages of using either the Bragg or Laue scattering geometries. Intensity front inclination in asymmetric diffraction can be used to make snapshots of ultrafast processes with femtosecond resolution.

  14. Spatiotemporal response of crystals in x-ray Bragg diffraction

    Directory of Open Access Journals (Sweden)

    Yuri Shvyd’ko

    2012-10-01

    Full Text Available The spatiotemporal response of crystals in x-ray Bragg diffraction resulting from excitation by an ultrashort, laterally confined x-ray pulse is studied theoretically. The theory presents an extension of the analysis in symmetric reflection geometry [R. R. Lindberg and Y. V. Shvyd’ko, Phys. Rev. ST Accel. Beams 15, 050706 (2012PRABFM1098-440210.1103/PhysRevSTAB.15.050706] to the generic case, which includes Bragg diffraction both in reflection (Bragg and transmission (Laue asymmetric scattering geometries. The spatiotemporal response is presented as a product of a crystal-intrinsic plane-wave spatiotemporal response function and an envelope function defined by the crystal-independent transverse profile of the incident beam and the scattering geometry. The diffracted wave fields exhibit amplitude modulation perpendicular to the propagation direction due to both angular dispersion and the dispersion due to Bragg’s law. The characteristic measure of the spatiotemporal response is expressed in terms of a few parameters: the extinction length, crystal thickness, Bragg angle, asymmetry angle, and the speed of light. Applications to self-seeding of hard x-ray free-electron lasers are discussed, with particular emphasis on the relative advantages of using either the Bragg or Laue scattering geometries. Intensity front inclination in asymmetric diffraction can be used to make snapshots of ultrafast processes with femtosecond resolution.

  15. X-ray diffraction tomography with limited projection information.

    Science.gov (United States)

    Zhu, Zheyuan; Katsevich, Alexander; Kapadia, Anuj J; Greenberg, Joel A; Pang, Shuo

    2018-01-11

    X-ray diffraction tomography (XDT) records the spatially-resolved X-ray diffraction profile of an extended object. Compared to conventional transmission-based tomography, XDT displays high intrinsic contrast among materials of similar electron density and improves the accuracy in material identification thanks to the molecular structural information carried by diffracted photons. However, due to the weak diffraction signal, a tomographic scan covering the entire object typically requires a synchrotron facility to make the acquisition time more manageable. Imaging applications in medical and industrial settings usually do not require the examination of the entire object. Therefore, a diffraction tomography modality covering only the region of interest (ROI) and subsequent image reconstruction techniques with truncated projections are highly desirable. Here we propose a table-top diffraction tomography system that can resolve the spatially-variant diffraction form factor from internal regions within extended samples. We demonstrate that the interior reconstruction maintains the material contrast while reducing the imaging time by 6 folds. The presented method could accelerate the acquisition of XDT and be applied in portable imaging applications with a reduced radiation dose.

  16. Nanofabrication of Diffractive Soft X-ray Optics

    OpenAIRE

    Lindblom, Magnus

    2009-01-01

    This thesis summarizes the present status of the nanofabrication of diffractive optics, i.e. zone plates, and test objects for soft x-ray microscopy at KTH. The emphasis is on new and improved fabrication processes for nickel and germanium zone plates. A new concept in which nickel and germanium are combined in a zone plate is also presented. The main techniques used in the fabrication are electron beam lithography for the patterning, followed by plasma etching and electroplating for the stru...

  17. Coherent X-ray diffraction from collagenous soft tissues

    Energy Technology Data Exchange (ETDEWEB)

    Berenguer de la Cuesta, Felisa; Wenger, Marco P.E.; Bean, Richard J.; Bozec, Laurent; Horton, Michael A.; Robinson, Ian K.; (UCL)

    2009-09-11

    Coherent X-ray diffraction has been applied in the imaging of inorganic materials with great success. However, its application to biological specimens has been limited to some notable exceptions, due to the induced radiation damage and the extended nature of biological samples, the last limiting the application of most part of the phasing algorithms. X-ray ptychography, still under development, is a good candidate to overcome such difficulties and become a powerful imaging method for biology. We describe herein the feasibility of applying ptychography to the imaging of biological specimens, in particular collagen rich samples. We report here speckles in diffraction patterns from soft animal tissue, obtained with an optimized small angle X-ray setup that exploits the natural coherence of the beam. By phasing these patterns, dark field images of collagen within tendon, skin, bone, or cornea will eventually be obtained with a resolution of 60-70 nm. We present simulations of the contrast mechanism in collagen based on atomic force microscope images of the samples. Simulations confirmed the 'speckled' nature of the obtained diffraction patterns. Once inverted, the patterns will show the disposition and orientation of the fibers within the tissue, by enhancing the phase contrast between protein and no protein regions of the sample. Our work affords the application of the most innovative coherent X-ray diffraction tools to the study of biological specimens, and this approach will have a significant impact in biology and medicine because it overcomes many of the limits of current microscopy techniques.

  18. X-ray diffraction from single GaAs nanowires

    Energy Technology Data Exchange (ETDEWEB)

    Biermanns, Andreas

    2012-11-12

    In recent years, developments in X-ray focussing optics have allowed to produce highly intense, coherent X-ray beams with spot sizes in the range of 100 nm and below. Together with the development of new experimental stations, X-ray diffraction techniques can now be applied to study single nanometer-sized objects. In the present work, X-ray diffraction is applied to study different aspects of the epitaxial growth of GaAs nanowires. Besides conventional diffraction methods, which employ X-ray beams with dimensions of several tens of {mu}m, special emphasis lies on the use of nanodiffraction methods which allow to study single nanowires in their as-grown state without further preparation. In particular, coherent X-ray diffraction is applied to measure simultaneously the 3-dimensional shape and lattice parameters of GaAs nanowires grown by metal-organic vapor phase epitaxy. It is observed that due to a high density of zinc-blende rotational twins within the nanowires, their lattice parameter deviates systematically from the bulk zinc-blende phase. In a second step, the initial stage in the growth of GaAs nanowires on Si (1 1 1) surfaces is studied. This nanowires, obtained by Ga-assisted growth in molecular beam epitaxy, grow predominantly in the cubic zinc-blende structure, but contain inclusions of the hexagonal wurtzite phase close to their bottom interface. Using nanodiffraction methods, the position of the different structural units along the growth axis is determined. Because the GaAs lattice is 4% larger than silicon, these nanowires release their lattice mismatch by the inclusion of dislocations at the interface. Whereas NWs with diameters below 50 nm are free of strain, a rough interface structure in nanowires with diameters above 100 nm prevents a complete plastic relaxation, leading to a residual strain at the interface that decays elastically along the growth direction. Finally, measurements on GaAs-core/InAs-shell nanowire heterostructures are presented

  19. Portable energy dispersive X-ray fluorescence and X-ray diffraction and radiography system for archaeometry

    Energy Technology Data Exchange (ETDEWEB)

    Mendoza Cuevas, Ariadna, E-mail: ariadna@mail.or [Archaeometry Laboratory, Colegio Universitario San Geronimo de La Habana, Obispo, entre San Ignacio y Mercaderes, Habana Vieja, cp 10 100, Havana (Cuba); Perez Gravie, Homero, E-mail: homero.perezgravie@mail.co [Archaeometry Laboratory, Colegio Universitario San Geronimo de La Habana, Obispo, entre San Ignacio y Mercaderes, Habana Vieja, cp 10 100, Havana (Cuba)

    2011-03-21

    Starting on a laboratory developed portable X-ray fluorescence (PXRF) spectrometer; three different analytical results can be performed: analysis of chemical elements, analysis of major chemical crystalline phase and structural analysis, which represents a contribution to a new, low cost development of portable X-ray analyzer; since these results are respectively obtained with independent equipments for X-ray fluorescence, X-ray diffraction and radiography. Detection limits of PXRF were characterized using standard reference materials for ceramics, glass, bronze and bones, which are the main materials requiring quantitative analysis in art and archeological objects. A setup for simultaneous energy dispersive X-ray fluorescence and diffraction (ED (XRF-XRD)) in the reflection mode has been tested for in situ and non-destructive analysis according to the requirements of art objects inspection. The system uses a single low power X-ray tube and an X-ray energy dispersive detector to measure X-ray diffraction spectrum at a fixed angle. Application to the identification of jadeite-jade mineral in archeological objects by XRD is presented. A local high resolution radiography image obtained with the same low power X-ray tube allows for studies in painting and archeological bones.

  20. X-ray diffraction and Raman spectroscopy on Gd{sub 2}(Ti{sub 2-y}Te{sub y})O{sub 7} prepared at high pressure and high temperature

    Energy Technology Data Exchange (ETDEWEB)

    Heredia, A.R. [Instituto de Investigaciones en Materiales, Universidad Nacional Autonoma de Mexico, A. Postal 70-360, Mexico D.F. 04510 (Mexico); Garcia, M. Quintana; Mazariego, J.L. Perez [Facultad de Ciencias, Universidad Nacional Autonoma de Mexico, A. Postal 70-360, Mexico D.F. 04510 (Mexico); Escamilla, R., E-mail: rauleg@servidor.unam.m [Instituto de Investigaciones en Materiales, Universidad Nacional Autonoma de Mexico, A. Postal 70-360, Mexico D.F. 04510 (Mexico)

    2010-08-20

    A series of Te-substituted pyrochlores of stoichiometry Gd{sub 2}(Ti{sub 2-y}Te{sub y})O{sub 7} (y {<=} 0.2) were prepared under high-pressure and high-temperature conditions and characterized by X-ray diffraction, X-ray photoelectron spectroscopy and Raman spectroscopy. X-ray diffraction and X-ray photoelectron spectroscopy studies revealed that the Te{sup 4+} and Te{sup 6+} ions occupy the Ti{sup 4+}sites; the percentage of the contribution of Te{sup 6+} increases as tellurium content. These substitutions induce an increase of the volume of the TiO{sub 6} octahedron due to the increase in the Ti-O(2) bond length, which preserves the oxygen positional parameter (x{sub 48f}) and the Gd-O(1) bond length. Results of Raman spectroscopy showed a significant shift to higher frequencies of the E{sub g} mode associated to the O(2) sublattice, as well an increase in the full-width-at-half-maximum intensity (FWHM) of the F{sub 2g} mode (O-Gd-O bending) as the level of Te substitution for Ti increases. These results are discussed and compared with those reported in the literature.

  1. Ultrafast X-ray diffraction of laser-irradiated crystals

    CERN Document Server

    Heimann, P A; Kang, I; Johnson, S; Missalla, T; Chang, Z; Falcone, R W; Schönlein, R W; Glover, T E; Padmore, H A

    2001-01-01

    Coherent acoustic phonons have been observed in the X-ray diffraction of a laser-excited InSb crystal. Modeling based on time-dependent dynamical diffraction theory has allowed the extraction of fundamental constants, such as the electron-acoustic phonon coupling time. A dedicated beamline for time-resolved studies has been developed at the Advanced Light Source with special considerations toward high transmission, low scattering and a wide photon energy range. The facility combines a bend magnet beamline, time-resolved detectors and a femtosecond laser system.

  2. Nano structured materials studied by coherent X-ray diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Gulden, Johannes

    2013-03-15

    Structure determination with X-rays in crystallography is a rapidly evolving field. Crystallographic methods for structure determination are based on the assumptions about the crystallinity of the sample. It is vital to understand the structure of possible defects in the crystal, because they can influence the structure determination. All conventional methods to characterize defects require a modelling through simulated data. No direct methods exist to image the core of defects in crystals. Here a new method is proposed, which will enable to visualize the individual scatterers around and at defects in crystals. The method is based on coherent X-ray scattering. X-rays are perfectly suited since they can penetrate thick samples and buried structures can be investigated Recent developments increased the coherent flux of X-Ray sources such as synchrotrons by orders of magnitude. As a result, the use of the coherent properties of X-rays is emerging as a new aspect of X-ray science. New upcoming and operating X-ray laser sources will accelerate this trend. One new method which has the capacity to recover structural information from the coherently scattered photons is Coherent X-ray Diffraction Imaging (CXDI). The main focus of this thesis is the investigation of the structure and the dynamics of colloidal crystals. Colloidal crystals can be used as a model for atomic crystals in order to understand the growth and defect structure. Despite the large interest in these structures, many details are still unknown.Therefore, it is vital to develop new approaches to measure the core of defects in colloidal crystals. After an introduction into the basics of the field of coherent X-ray scattering, this thesis introduces a novel method, Small Angle Bragg Coherent Diffractive Imaging, (SAB-CDI). This new measurement technique which besides the relevance to colloidal crystals can be applied to a large variety of nano structured materials. To verify the experimental possibilities the

  3. Low-temperature phase transition in glycine-glutaric acid co-crystals studied by single-crystal X-ray diffraction, Raman spectroscopy and differential scanning calorimetry.

    Science.gov (United States)

    Zakharov, Boris A; Losev, Evgeniy A; Kolesov, Boris A; Drebushchak, Valeri A; Boldyreva, Elena V

    2012-06-01

    The occurrence of a first-order reversible phase transition in glycine-glutaric acid co-crystals at 220-230 K has been confirmed by three different techniques - single-crystal X-ray diffraction, polarized Raman spectroscopy and differential scanning calorimetry. The most interesting feature of this phase transition is that every second glutaric acid molecule changes its conformation, and this fact results in the space-group symmetry change from P2(1)/c to P1. The topology of the hydrogen-bonded motifs remains almost the same and hydrogen bonds do not switch to other atoms, although the hydrogen bond lengths do change and some of the bonds become inequivalent.

  4. Diffraction enhanced kinetic depth X-ray imaging

    Science.gov (United States)

    Dicken, A.

    An increasing number of fields would benefit from a single analytical probe that can characterise bulk objects that vary in morphology and/or material composition. These fields include security screening, medicine and material science. In this study the X-ray region is shown to be an effective probe for the characterisation of materials. The most prominent analytical techniques that utilise X-radiation are reviewed. The study then focuses on methods of amalgamating the three dimensional power of kinetic depth X-ray (KDFX) imaging with the materials discrimination of angular dispersive X-ray diffraction (ADXRD), thus providing KDEX with a much needed material specific counterpart. A knowledge of the sample position is essential for the correct interpretation of diffraction signatures. Two different sensor geometries (i.e. circumferential and linear) that are able to collect end interpret multiple unknown material diffraction patterns and attribute them to their respective loci within an inspection volume are investigated. The circumferential and linear detector geometries are hypothesised, simulated and then tested in an experimental setting with the later demonstrating a greater ability at discerning between mixed diffraction patterns produced by differing materials. Factors known to confound the linear diffraction method such as sample thickness and radiation energy have been explored and quantified with a possible means of mitigation being identified (i.e. via increasing the sample to detector distance). A series of diffraction patterns (following the linear diffraction approach) were obtained from a single phantom object that was simultaneously interrogated via KDEX imaging. Areas containing diffraction signatures matched from a threat library have been highlighted in the KDEX imagery via colour encoding and match index is inferred by intensity. This union is the first example of its kind and is called diffraction enhanced KDEX imagery. Finally an additional

  5. Hydrothermal formation of tobermorite studied by in situ X-ray diffraction under autoclave condition.

    Science.gov (United States)

    Kikuma, Jun; Tsunashima, Masamichi; Ishikawa, Tetsuji; Matsuno, Shin-ya; Ogawa, Akihiro; Matsui, Kunio; Sato, Masugu

    2009-09-01

    Hydrothermal formation of tobermorite from a pre-cured cake has been investigated by transmission X-ray diffraction (XRD) using high-energy X-rays from a synchrotron radiation source in combination with a newly designed autoclave cell. The autoclave cell has a large and thin beryllium window for wide-angle X-ray diffraction; nevertheless, it withstands a steam pressure of more than 1.2 MPa, which enables in situ XRD measurements in a temperature range of 373 to 463 K under a saturated steam pressure. Formation and/or decomposition of several components has been successfully observed during 7.5 h of reaction time. From the intensity changes of the intermediate materials, namely non-crystalline C-S-H and hydroxylellestadite, two pathways for tobermorite formation have been confirmed. Thus, the newly developed autoclave cell can be used for the analyses of reaction mechanisms under specific atmospheres and temperatures.

  6. High-Energy X-Ray Diffraction Analysis Tool

    Energy Technology Data Exchange (ETDEWEB)

    2011-11-29

    The functionality of heRXD includes the following: distance and angular calibration and viewing flat-panel detector images used for X-ray diffraction; image (polar) rebinning or "caking"; line position fitting in powder diffraction images; image segmentation or "blob finding"; crystal orentation indesing; and lattice vector refinement. These functionalities encompass a critical set analyzing teh data for high-energy diffraction measurements that are currently performed at synchrotron sources such as the Advanced Photon Source (APS). The software design modular and open source under LGPL. The intent is to provide a common framework and graphical user interface that has the ability to utillize internal as well as external subroutines to provide various optins for performing the fuctionalities listed above. The software will initially be deployed at several national user facilities--including APS, ALS, and CHESS--and then made available for download using a hosting service such as sourceforge.

  7. Ultrafast X-Ray Diffraction of Heterogeneous Solid Hydrogen

    Energy Technology Data Exchange (ETDEWEB)

    Levitan, Abraham [Olin College of Engineering, Needham, MA (United States)

    2015-08-19

    Angularly resolved x-ray diffraction at 5.5 keV establishes the structure of a 5 µm diameter solid hydrogen jet, providing a foundation for analysis of hydrogen in a warm dense matter state. The jet was composed of approximately 65 % ± 5% HCP and 35 % ± 5% FCC by volume with an average crystallite size on the order of hundreds of nanometers. Broadening in the angularly resolved spectrum provided strong evidence for anisotropic strain up to approximately 3 % in the HCP lattice. Finally, we found no evidence for orientational ordering of the crystal domains.

  8. X-ray Laue diffraction from crystals of xylose isomerase.

    OpenAIRE

    Farber, G. K.; Machin, P; Almo, S C; Petsko, G A; Hajdu, J.

    1988-01-01

    The Laue method (stationary crystal, polychromatic x-rays) was used to collect native and heavy-atom-derivative data on crystals of xylose isomerase (EC 5.3.1.5). These data were used to find the heavy-atom positions. The positions found by use of Laue data are the same as those found by use of monochromatic data collected on a diffractometer. These results confirm that Laue diffraction data sets, which can be obtained on a millisecond time scale, can be used to locate small molecules bound t...

  9. The three dimensional X-ray diffraction technique

    DEFF Research Database (Denmark)

    Juul Jensen, Dorte; Poulsen, Henning Friis

    2012-01-01

    This introductory tutorial describes the so called 3 dimensional X-ray diffraction (3DXRD) technique, which allows bulk non-destructive structural characterizations of crystalline materials. The motivations and history behind the development of this technique are described and its potentials are ...... are sketched. Examples of the use of the technique are given and future trends and developments are suggested. The primary aim of the paper is to give 3DXRD novices an easy introduction to the technique and to describe a way from a dream to reality and new results....

  10. Oxides neutron and synchrotron X-ray diffraction studies

    CERN Document Server

    Sosnowska, I M

    1999-01-01

    We review some results from several areas of oxide science in which neutron scattering and X-ray synchrotron scattering exercise a complementary role to high-resolution transmission electron microscopy. The very high-resolution time-of-flight neutron diffraction technique and its role in studies of the magnetic structure of oxides is especially reviewed. The selected topics of structural studies for the chosen oxides are: crystal and magnetic structure of the so-called cellular random systems, magnetic structure and phase transitions in ferrites and the behaviour of water in non-stoichiometric protonic conductors and in the opal silica-water system. (40 refs).

  11. X-ray diffraction study of oriented gels of titin

    Energy Technology Data Exchange (ETDEWEB)

    Vazina, A.A. [Institute of Theoretical and Experimental Biophysics of RAS, Institutskaya st. 3, Pushchino, Moscow region 142290 (Russian Federation); Gorbunova, N.P. [Institute of Theoretical and Experimental Biophysics of RAS, Institutskaya st. 3, Pushchino, Moscow region 142290 (Russian Federation); Lanina, N.F. [Institute of Theoretical and Experimental Biophysics of RAS, Institutskaya st. 3, Pushchino, Moscow region 142290 (Russian Federation)]. E-mail: lanina@iteb.ru; Dolbnya, I.P. [DUBBLE-CRG/ESRF, B.P.220, F-38043 Grenoble (France); Bras, W. [DUBBLE-CRG/ESRF, B.P.220, F-38043 Grenoble (France); Snigireva, I. [ESRF, B.P.220, F-38043 Grenoble (France)

    2005-05-01

    This work is concerned with the X-ray diffraction study of oriented gels of titin. A topological zig-zag model of a giant fibrillar molecule of titin is proposed. The model suggests that a titin molecule consists of successively joined anisotropic domains, and the long axes of adjacent domains are connected at a nearly right angle relative to each other but are not necessarily inclined at equal angles relative to the fibril axis. The structural mechanism of the high elasticity of the titin molecule is discussed in terms of the physics of structural transitions in crystalline polymers.

  12. High-pressure X-ray diffraction of L-ALANINE crystal

    DEFF Research Database (Denmark)

    Olsen, J.S.; Gerward, Leif; Souza, A.G.

    2006-01-01

    L-ALANINE has been studied by X-ray diffraction at ambient temperature and pressure up to 10.3 GPa. The material is found to transform to a tetragonal structure between 2 and 3 GPa. and to a monoclinic structure between 8 and 10 GPa. The experimental bulk modulus is 25(5) GPa for the orthorhombic...

  13. X-ray diffraction study of structural stability of giant proteoglycan molecules of mucus

    Science.gov (United States)

    Vazina, A. A.; Lanina, N. F.; Vasilieva, A. A.; Korneev, V. N.; Zabelin, A. V.; Polyakova, E. P.

    2009-05-01

    X-ray diffraction study of various native and modified gastrointestinal mucins was carried out using synchrotron radiation. The mucus X-ray patterns of mammals and invertebrates are very similar and display a large number of sharp diffraction rings at the spacing of about 4.65 nm, which are due to the helical packing of polysaccharide chains covalently connected to the protein core. A comparative analysis of the X-ray patterns obtained earlier by us from various samples of mucus and biological tissues showed that the 4.65(±0.15) nm spacing is a nanoscale structural invariant of giant proteoglycan molecules of both the mucus and the extracellular matrix of tissues. A role of structural dynamics of proteoglycan scaffolding of biological systems in mechanism of modifying adaptation of organisms to significant changes of temperature is discussed.

  14. X-ray diffraction study of structural stability of giant proteoglycan molecules of mucus

    Energy Technology Data Exchange (ETDEWEB)

    Vazina, A.A. [Institute of Theoretical and Experimental Biophysics, RAS, Institutskaya St. 3, 142290 Pushchino, Moscow Region (Russian Federation); Russian Research Center ' Kurchatov Institute' , 123182 Moscow (Russian Federation)], E-mail: vazina@iteb.ru; Lanina, N.F.; Vasilieva, A.A. [Institute of Theoretical and Experimental Biophysics, RAS, Institutskaya St. 3, 142290 Pushchino, Moscow Region (Russian Federation); Korneev, V.N. [Institute of Cell Biophysics, RAS, 142290 Pushchino (Russian Federation); Zabelin, A.V. [Russian Research Center ' Kurchatov Institute' , 123182 Moscow (Russian Federation); Polyakova, E.P. [Timiryazev Moscow Agricultural Academy, 127550 Moscow (Russian Federation)

    2009-05-11

    X-ray diffraction study of various native and modified gastrointestinal mucins was carried out using synchrotron radiation. The mucus X-ray patterns of mammals and invertebrates are very similar and display a large number of sharp diffraction rings at the spacing of about 4.65 nm, which are due to the helical packing of polysaccharide chains covalently connected to the protein core. A comparative analysis of the X-ray patterns obtained earlier by us from various samples of mucus and biological tissues showed that the 4.65({+-}0.15) nm spacing is a nanoscale structural invariant of giant proteoglycan molecules of both the mucus and the extracellular matrix of tissues. A role of structural dynamics of proteoglycan scaffolding of biological systems in mechanism of modifying adaptation of organisms to significant changes of temperature is discussed.

  15. A curved image-plate detector system for high-resolution synchrotron X-ray diffraction.

    Science.gov (United States)

    Sarin, P; Haggerty, R P; Yoon, W; Knapp, M; Berghaeuser, A; Zschack, P; Karapetrova, E; Yang, N; Kriven, W M

    2009-03-01

    The developed curved image plate (CIP) is a one-dimensional detector which simultaneously records high-resolution X-ray diffraction (XRD) patterns over a 38.7 degrees 2theta range. In addition, an on-site reader enables rapid extraction, transfer and storage of X-ray intensity information in response is not compromised in the unsaturated regions of the image plate, regardless of saturation in another region. The speed of XRD data acquisition together with excellent resolution afforded by the CIP detector is unique and opens up wide possibilities in materials research accessible through X-ray diffraction. This article presents details of the basic features, operation and performance of the CIP detector along with some examples of applications, including high-temperature XRD.

  16. In situ laser heating and radial synchrotron X-ray diffraction ina diamond anvil cell

    Energy Technology Data Exchange (ETDEWEB)

    Kunz, Martin; Caldwell, Wendel A.; Miyagi, Lowell; Wenk,Hans-Rudolf

    2007-06-29

    We report a first combination of diamond anvil cell radialx-ray diffraction with in situ laser heating. The laser-heating setup ofALS beamline 12.2.2 was modified to allow one-sided heating of a samplein a diamond anvil cell with an 80 W yttrium lithium fluoride laser whileprobing the sample with radial x-ray diffraction. The diamond anvil cellis placed with its compressional axis vertical, and perpendicular to thebeam. The laser beam is focused onto the sample from the top while thesample is probed with hard x-rays through an x-ray transparentboron-epoxy gasket. The temperature response of preferred orientation of(Fe,Mg)O is probed as a test experiment. Recrystallization was observedabove 1500 K, accompanied by a decrease in stress.

  17. X-ray Diffraction Study of Arsenopyrite at High Pressure

    Energy Technology Data Exchange (ETDEWEB)

    D Fan; M Ma; W Zhou; S Wei; Z Chen; H Xie

    2011-12-31

    The high-pressure X-ray diffraction study of a natural arsenopyrite was investigated up to 28.2 GPa using in situ angle-dispersive X-ray diffraction and a diamond anvil cell at National Synchrotron Light Source, Brookhaven National Laboratory. The 16:3:1 methanol-ethanol-water mixture was used as a pressure-transmitting medium. Pressures were measured using the ruby-fluorescence method. No phase change has been observed up to 28.2 GPa. The isothermal equation of state (EOS) was determined. The values of K{sub 0}, and K'{sub 0} refined with a third-order Birch-Murnaghan EOS are K{sub 0} = 123(9) GPa, and K'{sub 0} = 5.2(8). Furthermore, we confirm that the linear compressibilities ({beta}) along a, b and c directions of arsenopyrite is elastically isotropic ({beta}{sub a} = 6.82 x 10{sup -4}, {beta}{sub b} = 6.17 x 10{sup -4} and {beta}{sub c} = 6.57 x 10{sup -4} GPa{sup -1}).

  18. Femtosecond X-ray diffraction from two-dimensional protein crystals

    Directory of Open Access Journals (Sweden)

    Matthias Frank

    2014-03-01

    Full Text Available X-ray diffraction patterns from two-dimensional (2-D protein crystals obtained using femtosecond X-ray pulses from an X-ray free-electron laser (XFEL are presented. To date, it has not been possible to acquire transmission X-ray diffraction patterns from individual 2-D protein crystals due to radiation damage. However, the intense and ultrafast pulses generated by an XFEL permit a new method of collecting diffraction data before the sample is destroyed. Utilizing a diffract-before-destroy approach at the Linac Coherent Light Source, Bragg diffraction was acquired to better than 8.5 Å resolution for two different 2-D protein crystal samples each less than 10 nm thick and maintained at room temperature. These proof-of-principle results show promise for structural analysis of both soluble and membrane proteins arranged as 2-D crystals without requiring cryogenic conditions or the formation of three-dimensional crystals.

  19. Strain in nanoscale Germanium hut clusters on Si(001) studied by x-ray diffraction

    DEFF Research Database (Denmark)

    Steinfort, A.J.; Scholte, P.M.L.O.; Ettema, A.

    1996-01-01

    Scanning tunneling microscopy and synchrotron x-ray diffraction have been used to investigate nanoscale Ge hut clusters on Si(001). We have been able to identify the contributions to the scattered x-ray intensity which arise solely from the hut clusters and have shown that x-ray diffraction can b...

  20. Fabrication of large area X-ray diffraction grating for X-ray phase imaging

    Science.gov (United States)

    Noda, Daiji; Tokuoka, Atsushi; Katori, Megumi; Minamiyama, Yasuto; Yamashita, Kenji; Nishida, Satoshi; Hattori, Tadashi

    2012-07-01

    X-ray lithography, which uses highly directional synchrotron radiation, is one of the technologies that can be used for fabricating micrometer-sized structures. In X-ray lithography, the accuracy of the fabricated structure depends largely on the accuracy of the X-ray mask. Since X-ray radiation is highly directional, a micro-fabrication technology that produces un-tapered and high aspect ratio highly absorbent structures on a low absorbent membrane is required. Conventionally, a resin material is used as the support membrane for large area X-ray masks. However, resin membranes have the disadvantage that they can sag after several cycles of X-ray exposure due to the heat generated by the X-rays. Therefore, we proposed and used thin carbon wafers for the membrane material because carbon has an extremely small thermal expansion coefficient. We fabricated new carbon membrane X-ray masks, and these results of X-ray lithography demonstrate the superior performance.

  1. X-Ray Diffraction Study of the Internal Structure of Supercooled Water

    Science.gov (United States)

    Dorsch, Robert G.; Boyd, Bemrose

    1951-01-01

    A Bragg X-ray spectrometer equipped with a volume-sensitive Geiger counter and Soller slits and employing filtered molybdenum Ka radiation was used to obtain a set of diffracted intensity curves as a Punction of angle for supercooled water. Diffracted intensity curves in the temperature region of 21 to -16 C were obtained. The minimum between the two main diffraction peaks deepened continuously with lowering temperature, indicating a gradual change in the internal structure of the water. No discontinuity in this trend was noted at the melting point. The internal structure of supercooled water was concluded to become progressively more ice-like as the temperature is lowered.

  2. Simultaneous X-ray fluorescence and scanning X-ray diffraction microscopy at the Australian Synchrotron XFM beamline

    Energy Technology Data Exchange (ETDEWEB)

    Jones, Michael W. M.; Phillips, Nicholas W.; van Riessen, Grant A.; Abbey, Brian; Vine, David J.; Nashed, Youssef S. G.; Mudie, Stephen T.; Afshar, Nader; Kirkham, Robin; Chen, Bo; Balaur, Eugeniu; de Jonge, Martin D.

    2016-08-11

    Owing to its extreme sensitivity, quantitative mapping of elemental distributionsviaX-ray fluorescence microscopy (XFM) has become a key microanalytical technique. The recent realisation of scanning X-ray diffraction microscopy (SXDM) meanwhile provides an avenue for quantitative super-resolved ultra-structural visualization. The similarity of their experimental geometries indicates excellent prospects for simultaneous acquisition. Here, in both step- and fly-scanning modes, robust, simultaneous XFM-SXDM is demonstrated.

  3. X-Ray Diffraction and Fluorescence Instrument for Mineralogical Analysis at the Lunar Surface Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose to develop a compact and lightweight X-Ray Diffraction (XRD) / X-Ray Fluorescence (XRF) instrument for analysis of mineralogical composition of regolith,...

  4. X-Ray Diffraction and Fluorescence Instrument for Mineralogical Analysis at the Lunar Surface Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose to develop LUNA, a compact and lightweight X-Ray Diffraction (XRD) / X-Ray Fluorescence (XRF) instrument for mineralogical analysis of regolith, rock...

  5. Acemetacin cocrystal structures by powder X-ray diffraction

    Directory of Open Access Journals (Sweden)

    Geetha Bolla

    2017-05-01

    Full Text Available Cocrystals of acemetacin drug (ACM with nicotinamide (NAM, p-aminobenzoic acid (PABA, valerolactam (VLM and 2-pyridone (2HP were prepared by melt crystallization and their X-ray crystal structures determined by high-resolution powder X-ray diffraction. The powerful technique of structure determination from powder data (SDPD provided details of molecular packing and hydrogen bonding in pharmaceutical cocrystals of acemetacin. ACM–NAM occurs in anhydrate and hydrate forms, whereas the other structures crystallized in a single crystalline form. The carboxylic acid group of ACM forms theacid–amide dimer three-point synthon R32(9R22(8R32(9 with three different syn amides (VLM, 2HP and caprolactam. The conformations of the ACM molecule observed in the crystal structures differ mainly in the mutual orientation of chlorobenzene fragment and the neighboring methyl group, being anti (type I or syn (type II. ACM hydrate, ACM—NAM, ACM–NAM-hydrate and the piperazine salt of ACM exhibit the type I conformation, whereas ACM polymorphs and other cocrystals adopt the ACM type II conformation. Hydrogen-bond interactions in all the crystal structures were quantified by calculating their molecular electrostatic potential (MEP surfaces. Hirshfeld surface analysis of the cocrystal surfaces shows that about 50% of the contribution is due to a combination of strong and weak O...H, N...H, Cl...H and C...H interactions. The physicochemical properties of these cocrystals are under study.

  6. The first X-ray diffraction measurements on Mars

    Directory of Open Access Journals (Sweden)

    David Bish

    2014-11-01

    Full Text Available The Mars Science Laboratory landed in Gale crater on Mars in August 2012, and the Curiosity rover then began field studies on its drive toward Mount Sharp, a central peak made of ancient sediments. CheMin is one of ten instruments on or inside the rover, all designed to provide detailed information on the rocks, soils and atmosphere in this region. CheMin is a miniaturized X-ray diffraction/X-ray fluorescence (XRD/XRF instrument that uses transmission geometry with an energy-discriminating CCD detector. CheMin uses onboard standards for XRD and XRF calibration, and beryl:quartz mixtures constitute the primary XRD standards. Four samples have been analysed by CheMin, namely a soil sample, two samples drilled from mudstones and a sample drilled from a sandstone. Rietveld and full-pattern analysis of the XRD data reveal a complex mineralogy, with contributions from parent igneous rocks, amorphous components and several minerals relating to aqueous alteration. In particular, the mudstone samples all contain one or more phyllosilicates consistent with alteration in liquid water. In addition to quantitative mineralogy, Rietveld refinements also provide unit-cell parameters for the major phases, which can be used to infer the chemical compositions of individual minerals and, by difference, the composition of the amorphous component.

  7. X-ray wavefront modeling of Bragg diffraction from crystals

    Science.gov (United States)

    Sutter, John P.

    2011-09-01

    The diffraction of an X-ray wavefront from a slightly distorted crystal can be modeled by the Takagi-Taupin theory, an extension of the well-known dynamical diffraction theory for perfect crystals. Maxwell's equations applied to a perturbed periodic medium yield two coupled differential equations in the incident and diffracted amplitude. These equations are discretized for numerical calculation into the determination of the two amplitudes on the points of an integration mesh, beginning with the incident amplitudes at the crystal's top surface. The result is a set of diffracted amplitudes on the top surface (in the Bragg geometry) or the bottom surface (in the Laue geometry), forming a wavefront that in turn can be propagated through free space using the Fresnel- Huygens equations. The performance of the Diamond Light Source I20 dispersive spectrometer has here been simulated using this method. Methods are shown for transforming displacements calculated by finite element analysis into local lattice distortions, and for efficiently performing 3-D linear interpolations from these onto the Takagi-Taupin integration mesh, allowing this method to be extended to crystals under thermal load or novel mechanical bender designs.

  8. Coherent Diffraction Imaging with Hard X-Ray Waveguides

    Science.gov (United States)

    Caro, Liberato De; Giannini, Cinzia; Pelliccia, Daniele; Cedola, Alessia; Lagomarsino, Stefano

    2013-01-01

    Coherent X-ray diffraction imaging (CXDI) has been widely applied in the nanoscopic world, offering nanometric-scale imaging of noncrystallographic samples, and permitting the next-generation structural studies on living cells, single virus particles and biomolecules. The use of curved wavefronts in CXDI has caused a tidal wave in the already promising application of this emergent technique. The non-planarity of the wavefront allows to accelerate any iterative phase-retrieval process and to guarantee a reliable and unique solution. Nowadays, successful experiments have been performed with Fresnel zone plates and planar waveguides as optical elements. Here we describe the use of a single planar waveguide as well as two crossed waveguides in the experiments which first showed this optical element a promising tool for producing a line- or point-like coherent source, respectively.

  9. Quantitative biological imaging by ptychographic X-ray diffraction microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Giewekemeyer, Klaus; Kalbfleisch, Sebastian; Beerlink, Andre; Salditt, Tim [Institut fuer Roentgenphysik, Georg-August-Universitaet Goettingen (Germany); Thibault, Pierre; Dierolf, Martin; Pfeiffer, Franz [Department Physik (E17), Technische Universitaet Muenchen, Garching (Germany); Kewish, Cameron M. [Paul Scherrer Institut, Villigen PSI (Switzerland)

    2010-07-01

    Mesoscopic structures with specific functions are abundant in many cellular systems and have been well characterized by electron microscopy in the past. However, the quantitative study of the three-dimensional structure and density of subcellular components remains a difficult problem. In this contribution we show how these limitations could be overcome in the future by the application of recently introduced and now rapidly evolving coherent X-ray imaging techniques for quantitative biological imaging on the nanoscale. More specifically, we report on a recent scanning (ptychographic) diffraction experiment on unstained and unsliced freeze-dried cells of the bacterium Deinococcus radiourans using only a pinhole as beam defining optical element. As a result quantitative density projections well below optical resolution have been achieved.

  10. An x-ray diffraction study of ribosome structure.

    Science.gov (United States)

    Dolgov, A D; Ivanov, D A; Kapitonova, K A; Mokul'skii, M A

    1975-01-01

    Dense gels of E. coli 70 S ribosomes, their 50 S subunits, CM-like particles, RNP strands and their fragments, 38 S particles obtained from RNP strand folding upon addition of Mg2+ ions, and of unoriented salt-free and free rRNA sodium and magnesium salts were studied by X-ray diffraction. It was shown that under dense gel conditions RNA molecules contained in ribosomes unfolded by desalting, like all other particles considered here, have helical regions. Under these conditions free desalted RNA has no helical regions. Experimental data on X-ray scattering at medium angles were compared with the diffraction curves calculated for homogeneous prolate and oblate ellipsoids, for various ellipsoids containing a dense region or an internal cavity, and for ellipsoids containing internal periodic regions. The results indicate that the internal structure of the 50 S ribosome is periodic, i. e., its components form a periodic lattice. The lattice spacings are approximately 42 and 28 A with a 0.8g/g dry weight sample water content. When the 50 S particle water content drops below 0.2 g/g dry weight the periodic structure is disrupted. This disruption is reversible. It was shown that CM-like particles at high ionic strenght (2 M LiCl) have approximately the same internal periodicity as the 50 S particles, but in contrast they lose this periodicity at low ionic strength (10-2M tris-HCl and 5-10-3 M MgCl2).

  11. Development of a high temperature unicam camera and application to X-ray diffraction on powdered uranium; Mise au point d'une chambre unicam a haute temperature et application a la diffraction de rayons X sur l'uranium en poudre

    Energy Technology Data Exchange (ETDEWEB)

    Laugier, J.; Blum, P.L.; Debrenne, P. [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

    1964-07-01

    A high temperature commercial X-ray camera (UNICAM S150), modified in order to improve some of its performances, is adapted to the uranium powder problem. The strong uranium reactivity for oxygen and silica, the sintering and the grain growth in {beta}-phase are avoided. X-ray photographs are thus possible even in the {gamma}-phase. (authors) [French] Une chambre commerciale de diffraction de rayons X a haute temperature, UNICAM SI50, modifiee en vue d'ameliorer certaines performances, a ete adaptee au probleme de la diffraction sur l'uranium en poudre. En particulier, la reaction avec la silice et l'oxygene, le frittage et l'accroissement du grain en phase {beta} sont evites. L'examen et les mesures sont ainsi possibles jusqu'en phase {gamma}. (auteurs)

  12. Line x-ray source for diffraction enhanced imaging in clinical and industrial applications

    Science.gov (United States)

    Wang, Xiaoqin

    Mammography is one type of imaging modalities that uses a low-dose x-ray or other radiation sources for examination of breasts. It plays a central role in early detection of breast cancers. The material similarity of tumor-cell and health cell, breast implants surgery and other factors, make the breast cancers hard to visualize and detect. Diffraction enhanced imaging (DEI), first proposed and investigated by D. Chapman is a new x-ray radiographic imaging modality using monochromatic x-rays from a synchrotron source, which produced images of thick absorbing objects that are almost completely free of scatter. It shows dramatically improved contrast over standard imaging when applied to the same phantom. The contrast is based not only on attenuation but also on the refraction and diffraction properties of the sample. This imaging method may improve image quality of mammography, other medical applications, industrial radiography for non-destructive testing and x-ray computed tomography. However, the size, and cost, of a synchrotron source limits the application of the new modality to be applicable at clinical levels. This research investigates the feasibility of a designed line x-ray source to produce intensity compatible to synchrotron sources. It is composed of a 2-cm in length tungsten filament, installed on a carbon steel filament cup (backing plate), as the cathode and a stationary oxygen-free copper anode with molybdenum coating on the front surface serves as the target. Characteristic properties of the line x-ray source were computationally studied and the prototype was experimentally investigated. SIMIION code was used to computationally study the electron trajectories emanating from the filament towards the molybdenum target. A Faraday cup on the prototype device, proof-of-principle, was used to measure the distribution of electrons on the target, which compares favorably to computational results. The intensities of characteristic x-ray for molybdenum

  13. A CCD area detector for X-ray diffraction under high pressure for ...

    Indian Academy of Sciences (India)

    Details of a two-dimensional X-ray area detector developed using a charge coupled device, a image intensifier and a fibre optic taper are given. The detector system is especially optimized for angle dispersive X-ray diffraction set up using rotating anode generator as X-ray source. The performance of this detector was ...

  14. A CCD area detector for X-ray diffraction under high pressure for ...

    Indian Academy of Sciences (India)

    Unknown

    Abstract. Details of a two-dimensional X-ray area detector developed using a charge coupled device, a image intensifier and a fibre optic taper are given. The detector system is especially optimized for angle dispersive X-ray diffraction set up using rotating anode generator as X-ray source. The performance of this detector ...

  15. X-ray diffraction and molecular-dynamics studies: Structural analysis of phases in diglyceride monolayers

    DEFF Research Database (Denmark)

    Peters, Günther H.J.; Larsen, Niels Bent; Bjørnholm, T.

    1998-01-01

    We report a detailed structural analysis of the phases of 1,2-sn-dipalmitoylglycerol Langmuir monolayers at room temperature. Pressure-induced transitions have been investigated by combination of molecular-dynamics simulations and grazing-incidence x-ray diffraction (XRD). The diglyceride film...... indicate that in the simulated monolayer the finite size with periodic boundary conditions imposes a higher degree of order....

  16. Quantitative firing transformations of a triaxial ceramic by X-ray diffraction methods

    Directory of Open Access Journals (Sweden)

    M. S. Conconi

    2014-12-01

    Full Text Available The firing transformations of traditional (clay based ceramics are of technological and archeological interest, and are usually reported qualitatively or semiquantitatively. These kinds of systems present an important complexity, especially for X-ray diffraction techniques, due to the presence of fully crystalline, low crystalline and amorphous phases. In this article we present the results of a qualitative and quantitative X-ray diffraction Rietveld analysis of the fully crystalline (kaolinite, quartz, cristobalite, feldspars and/or mullite, the low crystalline (metakaolinite and/or spinel type pre-mullite and glassy phases evolution of a triaxial (clay-quartz-feldspar ceramic fired in a wide temperature range between 900 and 1300 ºC. The employed methodology to determine low crystalline and glassy phase abundances is based in a combination of the internal standard method and the use of a nanocrystalline model where the long-range order is lost, respectively. A preliminary sintering characterization was carried out by contraction, density and porosity evolution with the firing temperature. Simultaneous thermo-gravimetric and differential thermal analysis was carried out to elucidate the actual temperature at which the chemical changes occur. Finally, the quantitative analysis based on the Rietveld refinement of the X-ray diffraction patterns was performed. The kaolinite decomposition into metakaolinite was determined quantitatively; the intermediate (980 ºC spinel type alumino-silicate formation was also quantified; the incongruent fusion of the potash feldspar was observed and quantified together with the final mullitization and the amorphous (glassy phase formation.The methodology used to analyze the X-ray diffraction patterns proved to be suitable to evaluate quantitatively the thermal transformations that occur in a complex system like the triaxial ceramics. The evaluated phases can be easily correlated with the processing variables and

  17. Quantitative firing transformations of a triaxial ceramic by X-ray diffraction methods

    Energy Technology Data Exchange (ETDEWEB)

    Conconi, M.S.; Gauna, M.R.; Serra, M.F. [Centro de Tecnologia de Recursos Minerales y Ceramica (CETMIC), Buenos Aires (Argentina); Suarez, G.; Aglietti, E.F.; Rendtorff, N.M., E-mail: rendtorff@cetmic.unlp.edu.ar [Universidad Nacional de La Plata (UNLP), Buenos Aires (Argentina). Fac. de Ciencias Exactas. Dept. de Quimica

    2014-10-15

    The firing transformations of traditional (clay based) ceramics are of technological and archaeological interest, and are usually reported qualitatively or semi quantitatively. These kinds of systems present an important complexity, especially for X-ray diffraction techniques, due to the presence of fully crystalline, low crystalline and amorphous phases. In this article we present the results of a qualitative and quantitative X-ray diffraction Rietveld analysis of the fully crystalline (kaolinite, quartz, cristobalite, feldspars and/or mullite), the low crystalline (metakaolinite and/or spinel type pre-mullite) and glassy phases evolution of a triaxial (clay-quartz-feldspar) ceramic fired in a wide temperature range between 900 and 1300 deg C. The employed methodology to determine low crystalline and glassy phase abundances is based in a combination of the internal standard method and the use of a nanocrystalline model where the long-range order is lost, respectively. A preliminary sintering characterization was carried out by contraction, density and porosity evolution with the firing temperature. Simultaneous thermo-gravimetric and differential thermal analysis was carried out to elucidate the actual temperature at which the chemical changes occur. Finally, the quantitative analysis based on the Rietveld refinement of the X-ray diffraction patterns was performed. The kaolinite decomposition into metakaolinite was determined quantitatively; the intermediate (980 deg C) spinel type alumino-silicate formation was also quantified; the incongruent fusion of the potash feldspar was observed and quantified together with the final mullitization and the amorphous (glassy) phase formation.The methodology used to analyze the X-ray diffraction patterns proved to be suitable to evaluate quantitatively the thermal transformations that occur in a complex system like the triaxial ceramics. The evaluated phases can be easily correlated with the processing variables and materials

  18. X-ray diffraction and X-ray absorption spectroscopic analyses for intercalative nanohybrids with low crystallinity

    Directory of Open Access Journals (Sweden)

    Dae-Hwan Park

    2016-03-01

    Full Text Available Intercalation reactions can be achieved through ion-exchange, pillaring, and exfoliation–reassembling reactions to explore new intercalation compounds with desired electronic, electrochemical, and optical functions. Such intercalative nanohybrids with lamellar or porous structure have received much attention due to their potential applications such as catalysts, electrodes, selective adsorbents, stabilizing agents, and even drug delivery systems. In this review, we briefly introduce and highlight X-ray diffraction and X-ray absorption spectroscopy studies on the intercalative nanohybrids to understand their intracrystalline and electronic structures along with physicochemical functions.

  19. X-Ray Powder Diffraction with Guinier - Haegg Focusing Cameras

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Allan

    1970-12-15

    The Guinier - Haegg focusing camera is discussed with reference to its use as an instrument for rapid phase analysis. An actual camera and the alignment procedure employed in its setting up are described. The results obtained with the instrument are compared with those obtained with Debye - Scherrer cameras and powder diffractometers. Exposure times of 15 - 30 minutes with compounds of simple structure are roughly one-sixth of those required for Debye - Scherrer patterns. Coupled with the lower background resulting from the use of a monochromatic X-ray beam, the shorter exposure time gives a ten-fold increase in sensitivity for the detection of minor phases as compared with the Debye - Scherrer camera. Attention is paid to the precautions taken to obtain reliable Bragg angles from Guinier - Haegg film measurements, with particular reference to calibration procedures. The evaluation of unit cell parameters from Guinier - Haegg data is discussed together with the application of tests for the presence of angle-dependent systematic errors. It is concluded that with proper calibration procedures and least squares treatment of the data, accuracies of the order of 0.005% are attainable. A compilation of diffraction data for a number of compounds examined in the Active Central Laboratory at Studsvik is presented to exemplify the scope of this type of powder camera.

  20. Federated repositories of X-ray diffraction images.

    Science.gov (United States)

    Androulakis, Steve; Schmidberger, Jason; Bate, Mark A; DeGori, Ross; Beitz, Anthony; Keong, Cyrus; Cameron, Bob; McGowan, Sheena; Porter, Corrine J; Harrison, Andrew; Hunter, Jane; Martin, Jennifer L; Kobe, Bostjan; Dobson, Renwick C J; Parker, Michael W; Whisstock, James C; Gray, Joan; Treloar, Andrew; Groenewegen, David; Dickson, Neil; Buckle, Ashley M

    2008-07-01

    There is a pressing need for the archiving and curation of raw X-ray diffraction data. This information is critical for validation, methods development and improvement of archived structures. However, the relatively large size of these data sets has presented challenges for storage in a single worldwide repository such as the Protein Data Bank archive. This problem can be avoided by using a federated approach, where each institution utilizes its institutional repository for storage, with a discovery service overlaid. Institutional repositories are relatively stable and adequately funded, ensuring persistence. Here, a simple repository solution is described, utilizing Fedora open-source database software and data-annotation and deposition tools that can be deployed at any site cheaply and easily. Data sets and associated metadata from federated repositories are given a unique and persistent handle, providing a simple mechanism for search and retrieval via web interfaces. In addition to ensuring that valuable data is not lost, the provision of raw data has several uses for the crystallographic community. Most importantly, structure determination can only be truly repeated or verified when the raw data are available. Moreover, the availability of raw data is extremely useful for the development of improved methods of image analysis and data processing.

  1. Characterization of Polycrystalline Materials Using Synchrotron X-ray Imaging and Diffraction Techniques

    DEFF Research Database (Denmark)

    Ludwig, Wolfgang; King, A.; Herbig, M.

    2010-01-01

    The combination of synchrotron radiation x-ray imaging and diffraction techniques offers new possibilities for in-situ observation of deformation and damage mechanisms in the bulk of polycrystalline materials. Minute changes in electron density (i.e., cracks, porosities) can be detected using...... propagation based phase contrast imaging, a 3-D imaging mode exploiting the coherence properties of third generation synchrotron beams. Furthermore, for some classes of polycrystalline materials, one may use a 3-D variant of x-ray diffraction imaging, termed x-ray diffraction contrast tomography. X-ray...

  2. X-ray diffraction-based electronic structure calculations and experimental x-ray analysis for medical and materials applications

    Science.gov (United States)

    Mahato, Dip Narayan

    This thesis includes x-ray experiments for medical and materials applications and the use of x-ray diffraction data in a first-principles study of electronic structures and hyperfine properties of chemical and biological systems. Polycapillary focusing lenses were used to collect divergent x rays emitted from conventional x-ray tubes and redirect them to form an intense focused beam. These lenses are routinely used in microbeam x-ray fluorescence analysis. In this thesis, their potential application to powder diffraction and focused beam orthovoltage cancer therapy has been investigated. In conventional x-ray therapy, very high energy (˜ MeV) beams are used, partly to reduce the skin dose. For any divergent beam, the dose is necessarily highest at the entry point, and decays exponentially into the tissue. To reduce the skin dose, high energy beams, which have long absorption lengths, are employed, and rotated about the patient to enter from different angles. This necessitates large expensive specialized equipment. A focused beam could concentrate the dose within the patient. Since this is inherently skin dose sparing, lower energy photons could be employed. A primary concern in applying focused beams to therapy is whether the focus would be maintained despite Compton scattering within the tissue. To investigate this, transmission and focal spot sizes as a function of photon energy of two polycapillary focusing lenses were measured. The effects of tissue-equivalent phantoms of different thicknesses on the focal spot size were studied. Scatter fraction and depth dose were calculated. For powder diffraction, the polycapillary optics provide clean Gaussian peaks, which result in angular resolution that is much smaller than the peak width due to the beam convergence. Powder diffraction (also called coherent scatter) without optics can also be used to distinguish between tissue types that, because they have different nanoscale structures, scatter at different angles

  3. Characterization of high-resolution diffractive X-ray optics by ptychographic coherent diffractive imaging.

    Science.gov (United States)

    Vila-Comamala, Joan; Diaz, Ana; Guizar-Sicairos, Manuel; Mantion, Alexandre; Kewish, Cameron M; Menzel, Andreas; Bunk, Oliver; David, Christian

    2011-10-24

    We have employed ptychographic coherent diffractive imaging to completely characterize the focal spot wavefield and wavefront aberrations of a high-resolution diffractive X-ray lens. The ptychographic data from a strongly scattering object was acquired using the radiation cone emanating from a coherently illuminated Fresnel zone plate at a photon energy of 6.2 keV. Reconstructed images of the object were retrieved with a spatial resolution of 8 nm by combining the difference-map phase retrieval algorithm with a non-linear optimization refinement. By numerically propagating the reconstructed illumination function, we have obtained the X-ray wavefield profile of the 23 nm round focus of the Fresnel zone plate (outermost zone width, Δr = 20 nm) as well as the X-ray wavefront at the exit pupil of the lens. The measurements of the wavefront aberrations were repeatable to within a root mean square error of 0.006 waves, and we demonstrate that they can be related to manufacturing aspects of the diffractive optical element and to errors on the incident X-ray wavefront introduced by the upstream beamline optics. © 2011 Optical Society of America

  4. Characterization of Gas-Solid Reactions using In Situ Powder X-ray Diffraction

    DEFF Research Database (Denmark)

    Møller, Kasper Trans; Hansen, Bjarne Rosenlund Søndertoft; Dippel, Ann-Christin

    2014-01-01

    X-ray diffraction is a superior technique for structural characterization of crystalline matter. Here we review the use of in situ powder X-ray diffraction (PXD) mainly for real-time studies of solid/gas reactions, data analysis and the extraction of valuable knowledge of structural, chemical...

  5. X-Ray Diffraction Studies on the Thermal Stability of Calcium ...

    African Journals Online (AJOL)

    acer

    X-Ray Diffraction Studies on the Thermal Stability of Calcium-Strontium Hydroxyapatite ... X- ray diffraction technique has been used by several researchers to investigate the individual effect of some elements on the formation and some properties of apatite in synthetic and .... is consistent with the larger ionic radius of.

  6. X-Ray Diffraction and the Discovery of the Structure of DNA

    Science.gov (United States)

    Crouse, David T.

    2007-01-01

    A method is described for teaching the analysis of X-ray diffraction of DNA through a series of steps utilizing the original methods used by James Watson, Francis Crick, Maurice Wilkins and Rosalind Franklin. The X-ray diffraction pattern led to the conclusion of the basic helical structure of DNA and its dimensions while basic chemical principles…

  7. Reflection surface x-ray diffraction patterns: k-space images

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Hawoong [Fredrick Seitz Materials Research Laboratory, University of Illinois at Urbana-Champaign, 438D, 9700 South Cass Avenue, Argonne, Illinois 60439 (United States); Wu, Z. [Fredrick Seitz Materials Research Laboratory, University of Illinois at Urbana-Champaign, 104 South Goodwin Avenue, Urbana, Illinois 61801-2902 (United States); Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, 1304 West Green Street, Urbana, Illinois 61801-2980 (United States); Chiang, T.-C. [Fredrick Seitz Materials Research Laboratory, University of Illinois at Urbana-Champaign, 104 South Goodwin Avenue, Urbana, Illinois 61801-2902 (United States); Department of Physics, University of Illinois at Urbana-Champaign, 1110 West Green Street, Urbana, Illinois 61801-3080 (United States); Zschack, P. [Fredrick Seitz Materials Research Laboratory, University of Illinois at Urbana-Champaign, 438D, 9700 South Cass Avenue, Argonne, Illinois 60439 (United States); Jemian, P. [Fredrick Seitz Materials Research Laboratory, University of Illinois at Urbana-Champaign, 438D, 9700 South Cass Avenue, Argonne, Illinois 60439 (United States); Chen, Haydn [Fredrick Seitz Materials Research Laboratory, University of Illinois at Urbana-Champaign, 104 South Goodwin Avenue, Urbana, Illinois 61801-2902 (United States); Aburano, R. D. [Cypress Semiconductor, 3901 North First Street, San Jose, California 95134 (United States)

    2000-08-01

    For the past two decades, x-ray diffraction has been utilized for surface structural determination. Unlike reflection high-energy electron diffraction (RHEED) which is a complicated dynamical scattering process, x-ray surface analysis is simple and straightforward due to the kinematic nature of x rays. Using high brilliance x rays from an undulator beamline and a highly sensitive charge coupled device detector, we successfully observed RHEED-like x-ray diffraction patterns. The patterns were recorded during the preparation of Si(111)-(7x7), transformation to Ge/Si(111)-(5x5) and Ge growth. Also, simultaneous measurements of x-ray reflectivity and crystal truncation rods are shown feasible with this technique. (c) 2000 American Institute of Physics.

  8. Measuring the x-ray resolving power of bent potassium acid phthalate diffraction crystals.

    Science.gov (United States)

    Haugh, M J; Wu, M; Jacoby, K D; Loisel, G P

    2014-11-01

    This report presents the results from measuring the X-ray resolving power of a curved potassium acid phthalate (KAP(001)) spectrometer crystal using two independent methods. It is part of a continuing effort to measure the fundamental diffraction properties of bent crystals that are used to study various characteristics of high temperature plasmas. Bent crystals like KAP(001) do not usually have the same diffraction properties as corresponding flat crystals. Models that do exist to calculate the effect of bending the crystal on the diffraction properties have simplifying assumptions and their accuracy limits have not been adequately determined. The type of crystals that we measured is being used in a spectrometer on the Z machine at Sandia National Laboratories in Albuquerque, New Mexico. The first technique for measuring the crystal resolving power measures the X-ray spectral line width of the characteristic lines from several metal anodes. The second method uses a diode X-ray source and a double crystal diffractometer arrangement to measure the reflectivity curve of the KAP(001) crystal. The width of that curve is inversely proportional to the crystal resolving power. The measurement results are analyzed and discussed.

  9. High-resolution neutron and X-ray diffraction room-temperature studies of an H-FABP–oleic acid complex: study of the internal water cluster and ligand binding by a transferred multipolar electron-density distribution

    Directory of Open Access Journals (Sweden)

    E. I. Howard

    2016-03-01

    Full Text Available Crystal diffraction data of heart fatty acid binding protein (H-FABP in complex with oleic acid were measured at room temperature with high-resolution X-ray and neutron protein crystallography (0.98 and 1.90 Å resolution, respectively. These data provided very detailed information about the cluster of water molecules and the bound oleic acid in the H-FABP large internal cavity. The jointly refined X-ray/neutron structure of H-FABP was complemented by a transferred multipolar electron-density distribution using the parameters of the ELMAMII library. The resulting electron density allowed a precise determination of the electrostatic potential in the fatty acid (FA binding pocket. Bader's quantum theory of atoms in molecules was then used to study interactions involving the internal water molecules, the FA and the protein. This approach showed H...H contacts of the FA with highly conserved hydrophobic residues known to play a role in the stabilization of long-chain FAs in the binding cavity. The determination of water hydrogen (deuterium positions allowed the analysis of the orientation and electrostatic properties of the water molecules in the very ordered cluster. As a result, a significant alignment of the permanent dipoles of the water molecules with the protein electrostatic field was observed. This can be related to the dielectric properties of hydration layers around proteins, where the shielding of electrostatic interactions depends directly on the rotational degrees of freedom of the water molecules in the interface.

  10. Inorganic pyrophosphatase crystals from Thermococcus thioreducens for X-ray and neutron diffraction.

    Science.gov (United States)

    Hughes, Ronny C; Coates, Leighton; Blakeley, Matthew P; Tomanicek, Steve J; Langan, Paul; Kovalevsky, Andrey Y; García-Ruiz, Juan M; Ng, Joseph D

    2012-12-01

    Inorganic pyrophosphatase (IPPase) from the archaeon Thermococcus thioreducens was cloned, overexpressed in Escherichia coli, purified and crystallized in restricted geometry, resulting in large crystal volumes exceeding 5 mm3. IPPase is thermally stable and is able to resist denaturation at temperatures above 348 K. Owing to the high temperature tolerance of the enzyme, the protein was amenable to room-temperature manipulation at the level of protein preparation, crystallization and X-ray and neutron diffraction analyses. A complete synchrotron X-ray diffraction data set to 1.85 Å resolution was collected at room temperature from a single crystal of IPPase (monoclinic space group C2, unit-cell parameters a=106.11, b=95.46, c=113.68 Å, α=γ=90.0, β=98.12°). As large-volume crystals of IPPase can be obtained, preliminary neutron diffraction tests were undertaken. Consequently, Laue diffraction images were obtained, with reflections observed to 2.1 Å resolution with I/σ(I) greater than 2.5. The preliminary crystallographic results reported here set in place future structure-function and mechanism studies of IPPase.

  11. An x-ray powder diffraction study of the high temperature phase transitions in {alpha}-quartz-type AlPO{sub 4}-GaPO{sub 4} solid solutions

    Energy Technology Data Exchange (ETDEWEB)

    Haines, J [Laboratoire de Physicochimie de la Matiere Condensee, UMR CNRS 5617, Universite Montpellier II, cc 003, Place E Bataillon, F-34095 Montpellier, Cedex 5 (France); Cambon, O [Laboratoire de Physicochimie de la Matiere Condensee, UMR CNRS 5617, Universite Montpellier II, cc 003, Place E Bataillon, F-34095 Montpellier, Cedex 5 (France); Fraysse, G [Laboratoire de Physicochimie de la Matiere Condensee, UMR CNRS 5617, Universite Montpellier II, cc 003, Place E Bataillon, F-34095 Montpellier, Cedex 5 (France); Lee, A van der [Institut Europeen des Membranes de Montpellier, UMR-CNRS 5635, Universite Montpellier II, cc 047, 300 Avenue Prof. E Jeanbrau, F-34095 Montpellier, Cedex 5 (France)

    2005-07-20

    Al{sub 1-x}Ga{sub x}PO{sub 4} solid solutions (x = 0.3, 0.7) with the {alpha}-quartz-type structure were investigated up to 1208 K by x-ray powder diffraction. The composition Al{sub 0.7}Ga{sub 0.3}PO{sub 4} exhibits almost simultaneous transitions to the {beta}-quartz and {beta}-cristobalite forms at close to 1050 K. The tendency towards the {beta}-quartz type structure is found to be much less marked for the Ga-rich composition (x = 0.7) based on the temperature dependence of the cell parameters, molar volume, fractional atomic coordinates and tetrahedral tilt angle. Direct transformation to the {beta}-cristobalite form begins close to 1123 K. The {beta}-quartz form exists as a stable phase only for values below x = 0.3.

  12. The 100th anniversary of the discovery of X-ray diffraction

    Science.gov (United States)

    Ilyushin, A. S.; Kovalchuk, M. V.

    2012-09-01

    A general historical essay on studies related to the discovery of X-ray diffraction, beginning with the first works by W.C. Roentgen, W. Friedrich, P. Knipping, and M. Laue, is presented. The coming of age of X-ray diffraction as an efficient tool for determining crystal structure is considered. The pioneering studies by W.G. Bragg, W.L. Bragg, Yu.V. Wulf, and E.C. Fedorov are briefly reviewed. The contribution of the Russian scientific school to the development of X-ray studies is indicated. The modern state and the directions of development of X-ray physics are discussed.

  13. X-ray diffraction studies on single and mixed confectionery fats using synchrotron radiation

    Energy Technology Data Exchange (ETDEWEB)

    MacMillan, S.C.; Roberts, K.J.; Wells, M.; Polgreen, M.; Smith, I. [Heriot-Watt University, Edinburgh, (United Kingdom). Department of Mechanical and Chemical Engineering, Centre for Molecular and Interface Engineering

    1999-12-01

    Full text: Understanding and refining the molecular-scale processes involved in the manufacture of structured materials such as long-chain hydrocarbon compounds is important in many commercial areas such as the petrochemical, biochemical, food, pharmaceutical and soap industries. In such processes crystallisation is an important separation, purification and preparation technique. Despite this our knowledge of the crystallisation process itself is surprisingly limited. In order to improve the crystallisation of confectionery fats, the crystallisation of it`s main component, cocoa butter fat, must be properly understood. Cocoa butter fat can exhibit up to 6 polymorphic forms of different crystallographic structures with melting points varying from 17.3 deg C to 36.3 deg C. During the production of chocolate it is essential to control the polymorphic form of fats present, in order to produce a final product with the correct physical and rheological properties. Both shear rate and temperature are thought to play a crucial role in this process. The most widely used method for studying polymorphism is X-ray diffraction. Typical X-ray diffraction patterns of fats exhibit two groups of diffraction lines corresponding to the long and short spacings. The long spacings correspond to the planes formed by the methyl end groups and are dependent on the chain length and the angle of tilt of the component fatty acids of the glyceride molecules. The short spacings refer to the cross sectional packing of the hydrocarbon chain and are independent of the chain length. The relationship between crystallisation rate, polymorphic form, shear and the fat composition has for the first time been quantified, which will enable more accurate control of the polymorhic form in chocolate production. This has been achieved by developing an improved in-situ cell for X-ray studies. The X-ray studies are necessary for the examination of on-line studies under well controlled conditions of temperature

  14. Single shot diffraction of picosecond 8.7-keV x-ray pulses

    Directory of Open Access Journals (Sweden)

    F. H. O’Shea

    2012-02-01

    Full Text Available We demonstrate multiphoton, single shot diffraction images of x rays produced by inverse Compton scattering a high-power CO_{2} laser from a relativistic electron beam, creating a pulse of 8.7 keV x rays. The tightly focused, relatively high peak brightness electron beam and high photon density from the 2 J CO_{2} laser yielded 6×10^{7} x-ray photons over the full opening angle in a single shot. Single shot x-ray diffraction is performed by passing the x rays though a vertical slit and on to a flat silicon (111 crystal. 10^{2} diffracted photons were detected. The spectrum of the detected x rays is compared to simulation. The diffraction and detection of 10^{2} x rays is a key step to a more efficient time resolved diagnostic in which the number of observed x rays might reach 10^{4}; enabling a unique, flexible x-ray source as a sub-ps resolution diagnostic for studying the evolution of chemical reactions, lattice deformation and melting, and magnetism.

  15. Reactor for nano-focused x-ray diffraction and imaging under catalytic in situ conditions

    Science.gov (United States)

    Richard, M.-I.; Fernández, S.; Hofmann, J. P.; Gao, L.; Chahine, G. A.; Leake, S. J.; Djazouli, H.; De Bortoli, Y.; Petit, L.; Boesecke, P.; Labat, S.; Hensen, E. J. M.; Thomas, O.; Schülli, T.

    2017-09-01

    A reactor cell for in situ studies of individual catalyst nanoparticles or surfaces by nano-focused (coherent) x-ray diffraction has been developed. Catalytic reactions can be studied in flow mode in a pressure range of 10-2-103 mbar and temperatures up to 900 °C. This instrument bridges the pressure and materials gap at the same time within one experimental setup. It allows us to probe in situ the structure (e.g., shape, size, strain, faceting, composition, and defects) of individual nanoparticles using a nano-focused x-ray beam. Here, the setup was used to observe strain and facet evolution of individual model Pt catalysts during in situ experiments. It can be used for heating other (non-catalytically active) nanoparticles (e.g., nanowires) in inert or reactive gas atmospheres or vacuum as well.

  16. In Situ X-ray Diffraction Studies of (De)lithiation Mechanism in Silicon Nanowire Anodes

    KAUST Repository

    Misra, Sumohan

    2012-06-26

    Figure Persented: Silicon is a promising anode material for Li-ion batteries due to its high theoretical specific capacity. From previous work, silicon nanowires (SiNWs) are known to undergo amorphorization during lithiation, and no crystalline Li-Si product has been observed. In this work, we use an X-ray transparent battery cell to perform in situ synchrotron X-ray diffraction on SiNWs in real time during electrochemical cycling. At deep lithiation voltages the known metastable Li 15Si 4 phase forms, and we show that avoiding the formation of this phase, by modifying the SiNW growth temperature, improves the cycling performance of SiNW anodes. Our results provide insight on the (de)lithiation mechanism and a correlation between phase evolution and electrochemical performance for SiNW anodes. © 2012 American Chemical Society.

  17. In situ X-ray diffraction studies of (de)lithiation mechanism in silicon nanowire anodes.

    Science.gov (United States)

    Misra, Sumohan; Liu, Nian; Nelson, Johanna; Hong, Seung Sae; Cui, Yi; Toney, Michael F

    2012-06-26

    Silicon is a promising anode material for Li-ion batteries due to its high theoretical specific capacity. From previous work, silicon nanowires (SiNWs) are known to undergo amorphorization during lithiation, and no crystalline Li-Si product has been observed. In this work, we use an X-ray transparent battery cell to perform in situ synchrotron X-ray diffraction on SiNWs in real time during electrochemical cycling. At deep lithiation voltages the known metastable Li(15)Si(4) phase forms, and we show that avoiding the formation of this phase, by modifying the SiNW growth temperature, improves the cycling performance of SiNW anodes. Our results provide insight on the (de)lithiation mechanism and a correlation between phase evolution and electrochemical performance for SiNW anodes.

  18. Applications of X-ray powder diffraction in materials chemistry.

    Science.gov (United States)

    Skakle, Jan

    2005-01-01

    X-ray powder diffraction is a standard technique in materials chemistry, yet it is often still used in the laboratory as a "one-hit" technique, e.g. for fingerprinting and following the progress of reactions. It is important, however, that the wealth of information available from powder data is not overlooked. While it is only possible here to scratch the surface of possibilities, a range of examples from our research is used to emphasize some of the more accessible techniques and to highlight successes as well as potential problems. The first example is the study of solid solution formation in the oxide systems Ba(3-3x)La(2x)V2O8 and Sr(4-x)Ba(x)Mn3O10 and in the silicate-hydroxyapatite bioceramic, Ca10(PO4)6-x(SiO4)x(OH)2-x. Database mining is also explored, using three phases within the pseudobinary phase diagram Li3SbO4-CuO as examples. All three phases presented different challenges: the structure of Li3SbO4 had been previously reported in higher symmetry than was actually the case, Li3Cu2SbO6 was found to be isostructural with Li2TiO3 but the cation ordering had to be rationalized, and Li3CuSbO5 was believed to be triclinic, presenting challenges in indexing the powder pattern. Quantitative phase analysis is briefly discussed, with the emphasis both on success (determination of amorphous phase content in a novel cadmium arsenate phase) and on possible failure (compositional analysis in bone mineral); the reasons for the problems in the latter are also explored. Finally, the use of an area detector system has been shown to be of value in the study of orientational effects (or lack of them) in non- and partially-ordered biomaterials, including p-HEMA, annulus fibrosis of lumbar discs, and keratin in the horn of cow's hooves. Copyright 2005 The Japan Chemical Journal Forum and Wiley Periodicals, Inc

  19. X-ray diffraction and Raman spectroscopy studies of temperature and composition induced phase transitions in Ba{sub 2-x}Sr{sub x}ZnWO{sub 6} (0 {<=} x {<=} 2) double perovskite oxides

    Energy Technology Data Exchange (ETDEWEB)

    Manoun, Bouchaib, E-mail: manounb@gmail.com [Equipe Materiaux et environnement, Laboratoire des Procedes de Valorisation des Ressources Naturelles, des Materiaux et Environnement, FST Settat, Universite Hassan 1er, (Morocco); Ezzahi, A. [Equipe Materiaux et environnement, Laboratoire des Procedes de Valorisation des Ressources Naturelles, des Materiaux et Environnement, FST Settat, Universite Hassan 1er, (Morocco); Benmokhtar, S. [LRCPGM, Laboratoire de Recherche de Chimie-Physique Generale des Materiaux, Department of Chemistry, Faculty of Sciences Ben M' Sik, Casablanca (Morocco); Ider, A. [Equipe Materiaux et environnement, Laboratoire des Procedes de Valorisation des Ressources Naturelles, des Materiaux et Environnement, FST Settat, Universite Hassan 1er, (Morocco); Lazor, P. [Department of Earth Sciences, Uppsala University, SE-752 36, Uppsala (Sweden); Bih, L. [Laboratoire de Physico-Chimie des Materiaux, Departement de Chimie, FST Errachidia (Morocco); Igartua, J.M. [Fisika Aplikatua II, Zientzia eta Teknologia Fak., UPV/EHU, PB 644, Bilbao 48080 (Spain)

    2012-08-25

    Highlights: Black-Right-Pointing-Pointer Synthesis and characterization of new double perovskites. Black-Right-Pointing-Pointer High temperature studies of double perovskite using Raman spectroscopy. Black-Right-Pointing-Pointer Temperature and compositions induced phase transitions in these materials. Black-Right-Pointing-Pointer Structural determination/refinement of these compounds as a function of composition. - Abstract: X-ray diffraction and Raman spectroscopy studies of Sr doped double perovskites compound Ba{sub 2-x}Sr{sub x}ZnWO{sub 6} with (0 {<=} x {<=} 2) were investigated. As a function of composition while increasing strontium amount, the samples show two phase transitions from cubic to tetragonal phase and from tetragonal to monoclinic structure. Both Rietveld refinements and Raman studies showed that the first phase transition occurs between x = 1 and 1.2; the second phase transition is observed around x = 2. Furthermore, increasing the temperature for the compositions (1.2 {<=} x < 2), manifests the tetragonal to cubic phase transition. For x = 2 two phase transitions were observed as a function of temperature. For this series, the phase transitions are illustrated by considerable changes in the composition and temperature dependence of the modes. All the Raman modes show a linear behavior when the composition or temperature is increased, then the slope change indicating the symmetry change.

  20. X-ray micro diffraction study on mesostructured silica thin films

    CERN Document Server

    Noma, T; Miyata, H; Iida, A

    2001-01-01

    The local structure of highly ordered mesostructured silica films was investigated by using a synchrotron X-ray microbeam and a CCD X-ray detector. Two-dimensional X-ray diffraction patterns clearly showed the detailed arrangement of the mesostructures, in which the hexagonal mesochannels aligned uniaxially in the mesostructured silica films formed on a silica glass substrate with a rubbing-treated thin polyimide coating. The alignment direction was shown to be perpendicular to the rubbing direction. The grazing incidence condition revealed the structural anisotropy of the mesostructures, while normal incidence X-ray diffraction data indicated the in-plane structural uniformity of the films. Extra spots were observed in the diffraction patterns. This suggested that the X-ray beam reflected at the boundary of the mesostructured silica film and the substrate.

  1. Beam-induced damage on diffractive hard X-ray optics.

    Science.gov (United States)

    Nygård, K; Gorelick, S; Vila-Comamala, J; Färm, E; Bergamaschi, A; Cervellino, A; Gozzo, F; Patterson, B D; Ritala, M; David, C

    2010-11-01

    The issue of beam-induced damage on diffractive hard X-ray optics is addressed. For this purpose a systematic study on the radiation damage induced by a high-power X-ray beam is carried out in both ambient and inert atmospheres. Diffraction gratings fabricated by three different techniques are considered: electroplated Au gratings both with and without the polymer mold, and Ir-coated Si gratings. The beam-induced damage is monitored by X-ray diffraction and evaluated using scanning electron microscopy.

  2. On the theory of time-resolved x-ray diffraction

    DEFF Research Database (Denmark)

    Henriksen, Niels Engholm; Møller, Klaus Braagaard

    2008-01-01

    of the experimental diffraction signal for both types of X-ray sources. We present a simple analysis of time-resolved X-ray scattering for direct bond breaking in diatomic molecules. This essentially analytical approach highlights the relation between the signal and the time-dependent quantum distribution...

  3. Interaction between lipid monolayers and poloxamer 188: An X-ray reflectivity and diffraction study

    DEFF Research Database (Denmark)

    Wu, G.H.; Majewski, J.; Ege, C.

    2005-01-01

    The mechanism by which poloxamer 188 (P188) seals a damaged cell membrane is examined using the lipid monolayer as a model system. X-ray reflectivity and grazing-incidence x-ray diffraction results show that at low nominal lipid density, P188, by physically occupying the available area and phase...

  4. Crystallization via tubing microfluidics permits both in situ and ex situ X-ray diffraction.

    Science.gov (United States)

    Gerard, Charline J J; Ferry, Gilles; Vuillard, Laurent M; Boutin, Jean A; Chavas, Leonard M G; Huet, Tiphaine; Ferte, Nathalie; Grossier, Romain; Candoni, Nadine; Veesler, Stéphane

    2017-10-01

    A microfluidic platform was used to address the problems of obtaining diffraction-quality crystals and crystal handling during transfer to the X-ray diffractometer. Crystallization conditions of a protein of pharmaceutical interest were optimized and X-ray data were collected both in situ and ex situ.

  5. Dynamical effects in Bragg coherent x-ray diffraction imaging of finite crystals

    Science.gov (United States)

    Shabalin, A. G.; Yefanov, O. M.; Nosik, V. L.; Bushuev, V. A.; Vartanyants, I. A.

    2017-08-01

    We present simulations of Bragg coherent x-ray diffractive imaging (CXDI) data from finite crystals in the frame of the dynamical theory of x-ray diffraction. The developed approach is based on a numerical solution of modified Takagi-Taupin equations and can be applied for modeling of a broad range of x-ray diffraction experiments with finite three-dimensional crystals of arbitrary shape also in the presence of strain. We performed simulations for nanocrystals of a cubic and hemispherical shape of different sizes and provided a detailed analysis of artifacts in the Bragg CXDI reconstructions introduced by the dynamical diffraction. Based on our theoretical analysis we developed an analytical procedure to treat effects of refraction and absorption in the reconstruction. Our results elucidate limitations for the kinematical approach in the Bragg CXDI and suggest a natural criterion to distinguish between kinematical and dynamical cases in coherent x-ray diffraction on a finite crystal.

  6. Effects of oxygen partial pressure and annealing temperature on the residual stress of hafnium oxide thin-films on silicon using synchrotron-based grazing incidence X-ray diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Biswas, Debaleen [Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata 700 064 (India); Sinha, Anil Kumar [ISU, Raja Ramanna Centre for Advanced Technology, Indore 452 013 (India); Homi Bhabha National Institute, BARC, Mumbai 400 094 (India); Chakraborty, Supratic, E-mail: supratic.chakraborty@saha.ac.in [Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata 700 064 (India)

    2016-10-30

    Highlights: • Residual stress estimation thin hafnium oxide film with thickness of <10 nm. • A mathematical expression is proposed for stress estimation of thin-film using GIXRD. • Residual stress varies with argon content in Ar/O{sub 2} plasma and annealing temperature. • Variation of stress is explained by IL swelling and enhanced structural relaxation. - Abstract: Synchrotron radiation-based grazing incidence X-ray diffraction (GI-XRD) technique is employed here to estimate the residual stress of < 10 nm thin hafnium oxide film deposited on Si (100) substrate at different argon/oxygen ratios using reactive rf sputtering. A decrease in residual stress, tensile in nature, is observed at higher annealing temperature for the samples deposited with increasing argon ratio in the Ar/O{sub 2} plasma. The residual stress of the films deposited at higher p{sub Ar} (Ar:O{sub 2} = 4:1) is also found to be decreased with increasing annealing temperature. But the stress is more or less constant with annealing temperature for the films deposited at lower Ar/O{sub 2} (1:4) ratio. All the above phenomena can be explained on the basis of swelling of the interfacial layer and enhanced structural relaxation in the presence of excess Hf in hafnium oxide film during deposition.

  7. High Pressure X-ray Diffraction Study on Icosahedral Boron Arsenide (B12As2)

    Energy Technology Data Exchange (ETDEWEB)

    J Wu; H Zhu; D Hou; C Ji; C Whiteley; J Edgar; Y Ma

    2011-12-31

    The high pressure properties of icosahedral boron arsenide (B12As2) were studied by in situ X-ray diffraction measurements at pressures up to 25.5 GPa at room temperature. B12As2 retains its rhombohedral structure; no phase transition was observed in the pressure range. The bulk modulus was determined to be 216 GPa with the pressure derivative 2.2. Anisotropy was observed in the compressibility of B12As2-c-axis was 16.2% more compressible than a-axis. The boron icosahedron plays a dominant role in the compressibility of boron-rich compounds.

  8. Characteristic, parametric, and diffracted transition X-ray radiation for observation of accelerated particle beam profile

    Science.gov (United States)

    Chaikovska, I.; Chehab, R.; Artru, X.; Shchagin, A. V.

    2017-07-01

    The applicability of X-ray radiation for the observation of accelerated particle beam profiles is studied. Three types of quasi-monochromatic X-ray radiation excited by the particles in crystals are considered: characteristic X-ray radiation, parametric X-ray radiation, diffracted transition X-ray radiation. Radiation is collected at the right angle to the particle beam direction. It is show that the most intensive differential yield of X-ray radiation from Si crystal can be provided by characteristic radiation at incident electron energies up to tens MeV, by parametric radiation at incident electron energies from tens to hundreds MeV, by diffracted transition X-ray radiation at GeV and multi-GeV electron energies. Therefore these kinds of radiation are proposed for application to beam profile observation in the corresponding energy ranges of incident electrons. Some elements of X-ray optics for observation of the beam profile are discussed. The application of the DTR as a source of powerful tunable monochromatic linearly polarized X-ray beam excited by a multi-GeV electron beam on the crystal surface is proposed.

  9. High temperature behavior of eucryptite by means of in situ X ray diffraction studies; Comportamiento de la eucriptita a alta temperatura mediante estudio in situ por difraccion de Rayos X

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Moreno, O.; Khainakov, S.; Torrecillas, R.

    2012-11-01

    Eucryptite is a lithium aluminosilicate with striking thermal expansion properties: it has negative expansion, i. e. it contracts upon heating in one of its crystallographic dimensions. Due to this characteristic, eucryptite is used in the fabrication of very low coefficient of thermal expansion materials. Two different eucryptite solid solution compositions were synthesized in this study with Li{sub 2}O:Al{sub 2}O{sub 3}:SiO{sub 2} contents of 1:1:3 and 1:1:2. The synthesis was prepared using kaolinite, lithium carbonate and TEOS and o {gamma} Al{sub 2}O{sub 3}, respectively. High resolution X Ray diffraction characterization was performed at high temperature for both compositions between 25 and 1200 degree centigrade. The temperature effect on structure and composition was studied by determining cell parameters and crystal structures. The relation between the observed changes and the CTE variations with the sintering temperature of materials based in these compositions was finally determined. (Author) 19 refs.

  10. Definitive Mineralogy of Rocky and Icy Planets and Planetesimals Using Powder X-Ray Diffraction

    Science.gov (United States)

    Blake, D. F.; Sarrazin, P.

    2017-02-01

    X-ray diffraction is a definitive technique for mineral identification, quantification, and composition. Definitive mineralogical analysis can identify modern and ancient habitable environments and provide context for other measurements.

  11. Powder Handling Device for X-ray Diffraction Analysis with Minimal Sample Preparation Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This project consists of developing a Vibrating Sample Holder (VSH) for planetary X-Ray Diffraction (XRD) instruments. The principle of this novel sample handling...

  12. Powder Handling Device for X-ray Diffraction Analysis with Minimal Sample Preparation Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This project consists in developing a Vibrating Powder Handling System for planetary X-Ray Diffraction instruments. The principle of this novel sample handling...

  13. Base metal catalyzed graphitization of cellulose : A combined Raman spectroscopy, temperature-dependent X-ray diffraction and high-resolution transmission electron microscopy study

    NARCIS (Netherlands)

    Hoekstra, Jacco; Beale, Andrew M.; Soulimani, Fouad; Versluijs-Helder, Marjan; Geus, John W.; Jenneskens, Leonardus W.

    2015-01-01

    Microcrystalline cellulose (MCC) spheres homogeneously loaded with the nitrate salts of copper, nickel, cobalt, or iron are excellent model systems to establish the temperature at which highly dispersed base metal nanoparticles are formed as well as to establish the temperature at which catalytic

  14. Quantification of retained austenite by X-ray diffraction and saturation magnetization in a supermartensitic stainless steel

    Energy Technology Data Exchange (ETDEWEB)

    Sicupira, Felipe Lucas [Departamento de Engenharia Metalúrgica e de Materiais - Escola de Engenharia da UFMG, 31270–901 Belo Horizonte, MG (Brazil); Sandim, Maria José R.; Sandim, Hugo R.Z. [Escola de Engenharia de Lorena – USP, 12600–970 Lorena, SP (Brazil); Santos, Dagoberto Brandão [Departamento de Engenharia Metalúrgica e de Materiais - Escola de Engenharia da UFMG, 31270–901 Belo Horizonte, MG (Brazil); Renzetti, Reny Angela, E-mail: renzetti.ra@gmail.com [Universidade Federal de Itajubá - UNIFEI, 35903–087 Itabira, MG (Brazil)

    2016-05-15

    The good performance of supermartensitic stainless steels is strongly dependent on the volume fraction of retained austenite at room temperature. The present work investigates the effect of secondary tempering temperatures on this phase transformation and quantifies the amount of retained austenite by X-ray diffraction and saturation magnetization. The steel samples were tempered for 1 h within a temperature range of 600–800 °C. The microstructure was characterized using scanning electron microscopy and electron backscatter diffraction. Results show that the amount of retained austenite decreased with increasing secondary tempering temperature in both quantification methods. - Highlights: • The phase transformation during secondary tempering temperatures was observed. • Phases were quantified by X-ray diffraction and DC-saturation magnetization. • More retained austenite forms with increasing secondary tempering temperature. • The retained austenite is mainly located at the grain and lath boundaries.

  15. X-ray diffraction characterization of suspended structures forMEMS applications

    Energy Technology Data Exchange (ETDEWEB)

    Goudeau, P.; Tamura, N.; Lavelle, B.; Rigo, S.; Masri, T.; Bosseboeuf, A.; Sarnet, T.; Petit, J.-A.; Desmarres, J.-M.

    2005-09-15

    Mechanical stress control is becoming one of the major challenges for the future of micro and nanotechnologies. Micro scanning X-ray diffraction is one of the promising techniques that allows stress characterization in such complex structures at sub micron scales. Two types of MEMS structure have been studied: a bilayer cantilever composed of a gold film deposited on poly-silicon and a boron doped silicon bridge. X-ray diffraction results are discussed in view of numerical simulation experiments.

  16. Near diffraction limited coherent diffractive imaging with tabletop soft x-ray sources

    Energy Technology Data Exchange (ETDEWEB)

    Sandberg, Richard L; Raymondson, Daisy A; La-O-Vorakiat, Chan; Paul, Ariel; Murnane, Margaret M; Kapteyn, Henry C [Department of Physics and JILA, University of Colorado and NIST, Boulder, Colorado (United States); Schlotter, William F [Stanford Synchrotron Radiation Laboratory, SLAC, Menlo Park, California (United States); Raines, Kevin; Miao Jianwei, E-mail: richard.sandberg@colorado.ed [Department of Physics and Astronomy and California NanoSystems Institute, University of California, Los Angeles, California (United States)

    2009-09-01

    Tabletop coherent x-ray sources hold great promise for practical nanoscale imaging, in particular when coupled with diffractive imaging techniques. In initial work, we demonstrated lensless diffraction imaging using a tabletop high harmonic generation (HHG) source at 29 nm, achieving resolutions {approx} 200 nm. In recent work, we significantly enhanced our diffractive imaging resolution by implementing a new high numerical aperture (up to NA=0.6) scheme and field curvature correction where we achieved sub-100 nm resolution. Here we report the first demonstration of Fourier transform holography (FTH) with a tabletop SXR source, to acquire images with a resolution {approx} 90 nm. The resolution can be refined by applying phase retrieval. Additionally, we show initial results from FTH with 13.5 nm HHG radiation and demonstrate {approx} 180 nm resolution.

  17. Structural characterization of substituted lanthanum tungstates with X-ray and neutron diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Fantin, Andrea; Scherb, Tobias; Schumacher, Gerhard [Helmholtz-Zentrum Berlin fuer Materialen und Energie (Germany); Seeger, Janka; Meulenberg, Wilhelm A. [Forschungszentrum Juelich (Germany)

    2015-07-01

    Our work on proton conducting materials deals with structural characterization of two different series of substituted lanthanum tungstates: La5.4W(1-x)MxO12-delta with M=Mo,Re and 0<=x<=0.2. The main methods used to understand their crystal structure are Neutron Diffraction (ND) and High-Resolution X-Ray Diffraction (HRXRD). Experiments were carried at ILL (Grenoble, France) and PSI (Villigen, Switzerland). Different elemental contrast is reached with these complementary diffraction techniques. Our specimens consist of three cations (La, W, Mo or Re) and oxygen anions. In order to distinguish W (Z=74, b=4.86fm) and Re (Z=75, b=9.2fm) neutrons are needed, while for La (Z=57, b=8.2fm), W(Z=74, b=4.86fm) and Mo (Z=42, b=6.7fm) good contrast is also given by X-Rays. Combined refinements to model accurately anti-site disorder, position of the substituted elements and oxygen (Z=8, b=5.8fm) positions in this highly disordered material are mandatory. Measurements in dependence of temperature down to 1.5K confirm the structural model suggested by one of the coauthors without any unmodeled static disorder. Substitution and deuteration/humidification show no relevant structural changes.

  18. In situ examination of oxygen non-stoichiometry in La0.80Sr0.20CoO3−δ thin films at intermediate and low temperatures by x-ray diffraction

    KAUST Repository

    Biegalski, M. D.

    2014-04-21

    Structural evolution of epitaxial La0.80Sr 0.20CoO3-δ thin films under chemical and voltage stimuli was examined in situ using X-ray diffraction. The changes in lattice parameter (chemical expansivity) were used to quantify oxygen reduction reaction processes and vacancy concentration changes in lanthanum strontium cobaltite. At 550 °C, the observed lattice parameter reduction at an applied bias of -0.6 V was equivalent to that from the reducing condition of a 2% carbon monoxide atmosphere with an oxygen non-stoichiometry δ of 0.24. At lower temperatures (200 °C), the application of bias reduced the sample much more effectively than a carbon monoxide atmosphere and induced an oxygen non-stoichiometry δ of 0.47. Despite these large changes in oxygen concentration, the epitaxial thin film was completely re-oxidized and no signs of crystallinity loss or film amorphization were observed. This work demonstrates that the effects of oxygen evolution and reduction can be examined with applied bias at low temperatures, extending the ability to probe these processes with in-situ analytical techniques. © 2014 AIP Publishing LLC.

  19. Introducing an Optimized Method for Obtaining X-ray Diffraction Patterns of Biological Tissues

    Directory of Open Access Journals (Sweden)

    Ali Chaparian

    2012-03-01

    Full Text Available Introduction Individual X-Ray diffraction patterns of biological tissues are obtained via interference of coherent scattering with their electrons. Many scientists have distinguished normal and cancerous breast tissue, bone density, and urinary stone types using the X-Ray diffraction patterns resulting from coherent scattering. The goal of this study was to introduce an optimized method for obtaining X-ray diffraction patterns of different types from biological tissues. Materials and Methods A special tool constituting primary and scatter collimators as well as a sample holder was designed and built. All measurements were done using an X-ray tube, the above-mentioned tool, and a semiconductor detector (HPGe. The X-ray diffraction patterns of some tissue-equivalent materials (acrylic, polyethylene, nylon, and calcium carbonate and biological tissues (adipose, muscle, and bone were obtained. Results The corresponding peak positions for adipose, muscle, bone, acrylic, polyethylene, nylon, and calcium carbonate in corresponding X-ray diffraction patterns are located in 1.1±0.055 nm-1, 1.41±0.072, 1.6±0.08 nm-1, 0.8±0.04 nm-1, 1.03±0.051 nm-1, 1.22±0.061 nm-1, and 1.7 ± 0.085 nm-1, respectively. Conclusion The X-ray diffraction patterns obtained in this study were in good agreement relative to previous measurements in terms of peak position. This study introduces a useful setup for extraction of X-ray diffraction patterns from different biological tissues.

  20. Combining operando synchrotron X-ray tomographic microscopy and scanning X-ray diffraction to study lithium ion batteries

    Science.gov (United States)

    Pietsch, Patrick; Hess, Michael; Ludwig, Wolfgang; Eller, Jens; Wood, Vanessa

    2016-06-01

    We present an operando study of a lithium ion battery combining scanning X-ray diffraction (SXRD) and synchrotron radiation X-ray tomographic microscopy (SRXTM) simultaneously for the first time. This combination of techniques facilitates the investigation of dynamic processes in lithium ion batteries containing amorphous and/or weakly attenuating active materials. While amorphous materials pose a challenge for diffraction techniques, weakly attenuating material systems pose a challenge for attenuation-contrast tomography. Furthermore, combining SXRD and SRXTM can be used to correlate processes occurring at the atomic level in the crystal lattices of the active materials with those at the scale of electrode microstructure. To demonstrate the benefits of this approach, we investigate a silicon powder electrode in lithium metal half-cell configuration. Combining SXRD and SRXTM, we are able to (i) quantify the dissolution of the metallic lithium electrode and the expansion of the silicon electrode, (ii) better understand the formation of the Li15Si4 phase, and (iii) non-invasively probe kinetic limitations within the silicon electrode. A simple model based on the 1D diffusion equation allows us to qualitatively understand the observed kinetics and demonstrates why high-capacity electrodes are more prone to inhomogeneous lithiation reactions.

  1. Taking X-ray Diffraction to the Limit: Macromolecular Structures from Femtosecond X-ray Pulses and Diffraction Microscopy of Cells with Synchrotron Radiation

    Energy Technology Data Exchange (ETDEWEB)

    Chapman, H N; Miao, J; Kirz, J; Sayre, D; Hodgson, K O

    2003-10-01

    The methodology of X-ray crystallography has recently been successfully extended to the structure determination of non-crystalline specimens. The phase problem was solved by using the oversampling method, which takes advantage of ''continuous'' diffraction pattern from non-crystalline specimens. Here we review the principle of this newly developed technique and discuss the ongoing experiments of imaging non-periodic objects, like cells and cellular structures using coherent and bright X-rays from the 3rd generation synchrotron radiation. In the longer run, the technique may be applied to image single biomolecules by using the anticipated X-ray free electron lasers. Computer simulations have so far demonstrated two important steps: (1) by using an extremely intense femtosecond X-ray pulse, a diffraction pattern can be recorded from a macromolecule before radiation damage manifests itself, and (2) the phase information can be ab initio retrieved from a set of calculated noisy diffraction patterns of single protein molecules.

  2. X-ray diffraction and NMR data for the study of the location of idebenone and idebenol in model membranes

    Directory of Open Access Journals (Sweden)

    Victoria Gómez-Murcia

    2016-06-01

    Full Text Available Here we present some of our data about the interaction of idebenone and idebenol with dipalmitoyl-phosphatidylcholine (DPPC. In particular, we include data of small angle X-ray diffraction (SAXD and wide angle X-ray diffraction experiments, obtention of electronic profiles of the membranes, 2H-NMR and 31P-NMR, as part of the research article: “Both idebenone and idebenol are localized near the lipid-water interface of the membrane and increase its fluidity” (Gomez-Murcia et al., 2016 [1]. These data were obtained from model membranes that included different proportions of idebenone and idebenol, at temperatures both above and below of the gel to fluid phase. The X-ray experiments were carried out by using a modified Kratky compact camera (MBraun-Graz-Optical Systems, Graz Austria, incorporating two coupled linear position sensitive detectors. The NMR data were collected from a a Bruker Avance 600 instrument.

  3. X-ray diffraction and NMR data for the study of the location of idebenone and idebenol in model membranes.

    Science.gov (United States)

    Gómez-Murcia, Victoria; Torrecillas, Alejandro; deGodos, Ana M; Corbalán-García, Senena; Gómez-Fernández, Juan C

    2016-06-01

    Here we present some of our data about the interaction of idebenone and idebenol with dipalmitoyl-phosphatidylcholine (DPPC). In particular, we include data of small angle X-ray diffraction (SAXD) and wide angle X-ray diffraction experiments, obtention of electronic profiles of the membranes, (2)H-NMR and (31)P-NMR, as part of the research article: "Both idebenone and idebenol are localized near the lipid-water interface of the membrane and increase its fluidity" (Gomez-Murcia et al., 2016) [1]. These data were obtained from model membranes that included different proportions of idebenone and idebenol, at temperatures both above and below of the gel to fluid phase. The X-ray experiments were carried out by using a modified Kratky compact camera (MBraun-Graz-Optical Systems, Graz Austria), incorporating two coupled linear position sensitive detectors. The NMR data were collected from a a Bruker Avance 600 instrument.

  4. Dynamical x-ray diffraction from an icosahedral Al-Pd-Mn quasicrystal

    Energy Technology Data Exchange (ETDEWEB)

    Kycia, S.

    1996-04-23

    Primary extinction effects in diffraction from single grains of Al-Pd- Mn, and presumably many other FCI alloys, may be significant and should be corrected for prior to use of diffraction data in structural determinations. Probes based on dynamical diffraction effects, such as x-ray standing wave fluorescence, multiple beam interference, and x-ray transmission topographs, may now be used to study the bulk and surface structure of some quasicrystals. The observation of dynamical diffraction from icosahedral Al-Pd-Mn is a striking confirmation of the fact that quasicrystals can present a degree of structural perfection comparable to that found in the best periodic intermetallic crystals.

  5. Strength and structural phase transitions of gadolinium at high pressure from radial X-ray diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Xiong, Lun, E-mail: xionglun@ihep.ac.cn; Liu, Jing; Bai, Ligang; Li, Xiaodong; Lin, Chuanlong [Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049 (China); Lin, Jung-Fu [Department of Geological Sciences, Jackson School of Geosciences, The University of Texas at Austin, Texas 78712 (United States)

    2014-12-28

    Lattice strength and structural phase transitions of gadolinium (Gd) were determined under nonhydrostatic compression up to 55 GPa using an angle-dispersive radial x-ray diffraction technique in a diamond-anvil cell at room temperature. Three new phases of fcc structure, dfcc structure, and new monoclinic structure were observed at 25 GPa, 34 GPa, and 53 GPa, respectively. The radial x-ray diffraction data yield a bulk modulus K{sub 0} = 36(1) GPa with its pressure derivate K{sub 0}′ = 3.8(1) at the azimuthal angle between the diamond cell loading axis and the diffraction plane normal and diffraction plane ψ = 54.7°. With K{sub 0}′ fixed at 4, the derived K{sub 0} is 34(1) GPa. In addition, analysis of diffraction data with lattice strain theory indicates that the ratio of differential stress to shear modulus (t/G) ranges from 0.011 to 0.014 at pressures of 12–55 GPa. Together with estimated high-pressure shear moduli, our results show that Gd can support a maximum differential stress of 0.41 GPa, while it starts to yield to plastic deformation at 16 GPa under uniaxial compression. The yield strength of Gd remains approximately a constant with increasing pressure, and reaches 0.46 GPa at 55 GPa.

  6. In situ hydration of sulphoaluminate cement mixtures monitored by synchrotron x-ray diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Turrillas, X. [Institut de Ciencia de Materials de Barcelona (ICMAB-CSIC), Barcelona (Spain); Martinez, L.G.; Carvalho, A.M.; Carezzato, G.L. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Rossetto, C.M. [Faculdade de Tecnologia de Sao Paulo (FATEC), SP (Brazil)

    2016-07-01

    Full text: The hydration of calcium sulpho-aluminate cement mixtures was studied in situ by synchrotron X-ray diffraction at the XRD1 beamline of the Laboratorio Nacional de Luz Sincrotron (LNLS) in Campinas, SP. The powder specimens were introduced in borosilicate glass capillary tubes of 0.7 mm of internal diameter and imbued with deionized water. As the hydration reaction is very fast the capillaries were placed on the goniometer and the data collection was started after two minutes of mixing with water. The X-ray energy chosen to get an adequate flux for these short time acquisitions was 12 keV or more precisely 1.033258 Å, determined with polycrystalline corundum standard. Diffraction patterns were collected sequentially every 35 seconds for several hours at temperatures ranging from 40 degC to 55 degC with an accuracy better than 0.1 degC attained with the help of a hot air blower. The diffracted signal was collected with an array of twenty-four Mythen detectors at 760 mm from the capillary tube. The diffraction patterns had appropriate statistics to determine the kinetics of the reaction either by quantitative Rietveld analysis or by fitting isolated diffraction peaks to Gaussian curves as a function of time. The most important phases involved in the hydration are Klein´s salt, also known as Ye’elimite, Ca4(AlO2)6SO4, and gypsum, CaSO4.2H2O to yield Ettringite, Ca6Al2(SO4)3(OH)12 - 26H2O, phase responsible for the mechanical properties. (author)

  7. AN X-RAY-DIFFRACTION STUDY ON THE TEMPERATURE AND CHEMICAL-COMPOSITION DEPENDENCE OF THE MODULATION WAVE-VECTOR IN [(CH3)(4)N]2ZNCL4-XBRX COMPOUNDS

    NARCIS (Netherlands)

    VOGELS, LJP; MEEKES, H; DEBOER, JL

    1994-01-01

    In this paper we study the behaviour of the modulation wave vector in [(CH3)(4)N]2ZnCl4-xBrx compounds as a function of composition (x) and temperature. We compare the results of this x-ray study with those of morphological experiments. The two results are quite well correlated, showing several

  8. Capture and X-ray diffraction studies of protein microcrystals in a microfluidic trap array

    Energy Technology Data Exchange (ETDEWEB)

    Lyubimov, Artem Y. [Stanford University, Stanford, CA 94305 (United States); Stanford University, Stanford, CA 94305 (United States); Stanford University, Stanford, CA 94305 (United States); Stanford University, Stanford, CA 94305 (United States); Stanford University, Stanford, CA 94305 (United States); Murray, Thomas D. [University of California, Berkeley, CA 94720 (United States); Johns Hopkins University School of Medicine, Baltimore, MD 21205 (United States); Koehl, Antoine [Stanford University, Stanford, CA 94305 (United States); Araci, Ismail Emre [Stanford University, Stanford, CA 94305 (United States); Stanford University, Stanford, CA 94305 (United States); Uervirojnangkoorn, Monarin; Zeldin, Oliver B. [Stanford University, Stanford, CA 94305 (United States); Stanford University, Stanford, CA 94305 (United States); Stanford University, Stanford, CA 94305 (United States); Stanford University, Stanford, CA 94305 (United States); Stanford University, Stanford, CA 94305 (United States); Cohen, Aina E.; Soltis, S. Michael; Baxter, Elizabeth L. [SLAC National Accelerator Laboratory, Stanford, CA 94305 (United States); Brewster, Aaron S.; Sauter, Nicholas K. [Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Brunger, Axel T., E-mail: brunger@stanford.edu [Stanford University, Stanford, CA 94305 (United States); Stanford University, Stanford, CA 94305 (United States); Stanford University, Stanford, CA 94305 (United States); Stanford University, Stanford, CA 94305 (United States); Stanford University, Stanford, CA 94305 (United States); Berger, James M., E-mail: brunger@stanford.edu [Johns Hopkins University School of Medicine, Baltimore, MD 21205 (United States); Stanford University, Stanford, CA 94305 (United States)

    2015-04-01

    A microfluidic platform has been developed for the capture and X-ray analysis of protein microcrystals, affording a means to improve the efficiency of XFEL and synchrotron experiments. X-ray free-electron lasers (XFELs) promise to enable the collection of interpretable diffraction data from samples that are refractory to data collection at synchrotron sources. At present, however, more efficient sample-delivery methods that minimize the consumption of microcrystalline material are needed to allow the application of XFEL sources to a wide range of challenging structural targets of biological importance. Here, a microfluidic chip is presented in which microcrystals can be captured at fixed, addressable points in a trap array from a small volume (<10 µl) of a pre-existing slurry grown off-chip. The device can be mounted on a standard goniostat for conducting diffraction experiments at room temperature without the need for flash-cooling. Proof-of-principle tests with a model system (hen egg-white lysozyme) demonstrated the high efficiency of the microfluidic approach for crystal harvesting, permitting the collection of sufficient data from only 265 single-crystal still images to permit determination and refinement of the structure of the protein. This work shows that microfluidic capture devices can be readily used to facilitate data collection from protein microcrystals grown in traditional laboratory formats, enabling analysis when cryopreservation is problematic or when only small numbers of crystals are available. Such microfluidic capture devices may also be useful for data collection at synchrotron sources.

  9. Infield X-ray diffraction studies of field and temperature driven structural phase transition in Nd{sub 0.49}Sr{sub 0.51}MnO{sub 3+δ}

    Energy Technology Data Exchange (ETDEWEB)

    Shahee, Aga, E-mail: agashahee@gmail.com [UGC-DAE Consortium for Scientific Research, University Campus, Khandwa Road, Indore 452001 (India); Department of Physics, IIT Bombay, Powai, Mumbai 400076 (India); Sharma, Shivani; Singh, K.; Lalla, N.P. [UGC-DAE Consortium for Scientific Research, University Campus, Khandwa Road, Indore 452001 (India)

    2017-07-15

    Highlights: • Temperature and magnetic field driven coupled magneto-structural phase transition in Nd{sub 0.49}Sr{sub 0.51}MnO{sub 3+δ}. • Microscopic evidence of strong spin-charge-lattice coupling. • Iso-thermal magnetic field driven structure phase transition. • Field-driven structural phase transition origin of observed 1st order type CMR effect. - Abstract: Comprehensive X-ray diffraction (XRD) studies have been performed at different temperature (T) (4.2–300 K) and magnetic field (H) (0–8 T) to understand the evolution of crystal structure of Nd{sub 0.49}Sr{sub 0.51}MnO{sub 3+δ} (NSMO) under non ambient conditions. The T dependent XRD results show the abrupt change in the lattice parameters without any change in lattice symmetry at ∼200 K, which is associated with the first order structural phase transition from ferromagnetic to antiferromagnetic phase. This phase transition is strongly H dependent and shifted to lower temperature (∼150 K) on the application of 8 T field with phase coexistence (high temperature phase ∼18%), even down to 4.2 K. Isothermal XRD results at 150 K under different H clearly illustrate the H induced first order structural phase transition. The critical H at which this phase transformation starts is ∼1 T, with rapid growth above 4 T with hysteretic nature during increasing and decreasing H. These results are supported with the resistivity and magnetoresistance results and affirm the strong spin-lattice coupling in NSMO. Our detail studies reveal the structural correlations to the observed colossal magnetoresistance and magnetocaloric effect in this material.

  10. Small Angle X-ray Diffraction Study of DNA—Cationic Liposomes Aggregates

    Science.gov (United States)

    Pullmannová, Petra; Uhríková, Daniela; Funari, Sergio S.; Lacko, Ivan; Devínsky, Ferdinand; Balgavý, Pavol

    2010-01-01

    The microstructure of DNA—dioleoylphosphatidylethanolamine (DOPE)—propane-1,3-diyl-bis(dodecyldimethylammonium bromide) (C3GS12) aggregates as a function of the C3GS12:DOPE molar ratio and temperature was investigated using small angle X-ray diffraction. At 20° C, we observe a condensed lamellar phase (Lαc) with the lattice parameter d˜6.8-6.2 nm and the DNA—DNA distance dDNA˜5.8-3.2 nm decreasing with increasing content of C3GS12 in the phospholipid bilayer. Increase in temperature induces a phase transition from Lαc phase to condensed inverted hexagonal phase (HIIc). The temperature of the Lαc→HIIc phase transition increases with increasing C3GS12:DOPE molar ratio.

  11. Zirconium hydride precipitation kinetics in Zircaloy-4 observed with synchrotron X-ray diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Blackmur, M.S., E-mail: matthew.blackmur@postgrad.manchester.ac.uk [Materials Performance Centre, School of Materials, The University of Manchester, Manchester M1 7HS (United Kingdom); Robson, J.D.; Preuss, M. [Materials Performance Centre, School of Materials, The University of Manchester, Manchester M1 7HS (United Kingdom); Zanellato, O. [PIMM, Ensam – Cnam – CNRS, 151 Boulevard de l’Hôpital, 75013 Paris (France); Cernik, R.J. [Materials Performance Centre, School of Materials, The University of Manchester, Manchester M1 7HS (United Kingdom); Shi, S.-Q. [Department of Mechanical Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong (China); Ribeiro, F. [Institut de Radioprotection et de Sûreté Nucléaire, CEN Cadarache, 13115 St. Paul Les Durance (France); Andrieux, J. [Beamline ID15, European Synchrotron Radiation Facility, Grenoble (France)

    2015-09-15

    High-energy synchrotron X-ray diffraction was used to investigate the isothermal precipitation of δ-hydride platelets in Zircaloy-4 at a range of temperatures relevant to reactor conditions, during both normal operation and thermal transients. From an examination of the rate kinetics of the precipitation process, precipitation slows with increasing temperature above 200 °C, due to a reduction in the thermodynamic driving force. A model for nucleation rate as a function of temperature was developed, to interpret the precipitation rates seen experimentally. While the strain energy associated with the misfit between hydrides and the matrix makes a significant contribution to the energy barrier for nucleation, a larger contribution arises from the interfacial energy. Diffusion distance calculations show that hydrogen is highly mobile in the considered thermal range and on the scale of inter-hydride spacing and it is not expected to be significantly rate limiting on the precipitation process that takes place under reactor operating conditions.

  12. Comparison of a CCD and an APS for soft X-ray diffraction

    Science.gov (United States)

    Stewart, Graeme; Bates, R.; Blue, A.; Clark, A.; Dhesi, S. S.; Maneuski, D.; Marchal, J.; Steadman, P.; Tartoni, N.; Turchetta, R.

    2011-12-01

    We compare a new CMOS Active Pixel Sensor (APS) to a Princeton Instruments PIXIS-XO: 2048B Charge Coupled Device (CCD) with soft X-rays tested in a synchrotron beam line at the Diamond Light Source (DLS). Despite CCDs being established in the field of scientific imaging, APS are an innovative technology that offers advantages over CCDs. These include faster readout, higher operational temperature, in-pixel electronics for advanced image processing and reduced manufacturing cost. The APS employed was the Vanilla sensor designed by the MI3 collaboration and funded by an RCUK Basic technology grant. This sensor has 520 x 520 square pixels, of size 25 μm on each side. The sensor can operate at a full frame readout of up to 20 Hz. The sensor had been back-thinned, to the epitaxial layer. This was the first time that a back-thinned APS had been demonstrated at a beam line at DLS. In the synchrotron experiment soft X-rays with an energy of approximately 708 eV were used to produce a diffraction pattern from a permalloy sample. The pattern was imaged at a range of integration times with both sensors. The CCD had to be operated at a temperature of -55°C whereas the Vanilla was operated over a temperature range from 20°C to -10°C. We show that the APS detector can operate with frame rates up to two hundred times faster than the CCD, without excessive degradation of image quality. The signal to noise of the APS is shown to be the same as that of the CCD at identical integration times and the response is shown to be linear, with no charge blooming effects. The experiment has allowed a direct comparison of back thinned APS and CCDs in a real soft x-ray synchrotron experiment.

  13. Carbon Fiber Morphology. 2. Expanded Wide-Angle X-Ray Diffraction Studies of Carbon Fibers

    Science.gov (United States)

    1991-02-01

    X- Ray Diffraction," JPS. Polym. Phys. Ed., 16, 939 (1978). 17. Rosalind E. Franklin , "The Structure of Graphitic Carbons," Acta Cryst., 4, 253 (1951...18. Rosalind E. Franklin , "The Interpretation of Diffuse X-ray Diagrams of Carbon," Acta CrL, 3, 107 (1950). 19. K. Jain and A. S. Abhiraman...been generally mentioned much earlier by Franklin [17,18]. Jain and Abhiraman [19] demonstrated that these corrections can make significant differences

  14. Model experiment of in vivo synchrotron X-ray diffraction of human kidney stones

    Energy Technology Data Exchange (ETDEWEB)

    Ancharov, A.I. [Institute of Solid State Chemistry and Mechanochemistry SB RAS, Novosibirsk (Russian Federation)]. E-mail: ancharov@mail.ru; Potapov, S.S. [Institute of Mineralogy UB RAS, Miass (Russian Federation); Moiseenko, T.N. [The State Regional Clinical Hospital, Novosibirsk (Russian Federation); Feofilov, I.V. [The State Regional Clinical Hospital, Novosibirsk (Russian Federation); Nizovskii, A.I. [Boreskov Institute of Catalysis SB RAS, Novosibirsk (Russian Federation)

    2007-05-21

    The diffraction of synchrotron radiation (SR) was used to explore the phase composition of kidney stones placed into a specific object phantom, which imitated the human body. As an imitation of the patient breath, the kidney stone was moved vertically and rotated to an angle of 15{sup o} during the recording of the X-ray pattern. It was shown that rotation and displacement did not distort the X-ray pattern.

  15. KMC-2: an X-ray beamline with dedicated diffraction and XAS endstations at BESSY II

    Directory of Open Access Journals (Sweden)

    Daniel M. Többens

    2016-02-01

    Full Text Available The KMC-2 beamline is dedicated to provide X-ray radiation with high energy stability and resolution. The experimental setup is optimized towards offering a wide range of methods and sample environments. Two permanent endstations can be used in alternation. DIFFRACTION is a flexible multi-purpose diffractometer, based on a Huber six circle diffractometer in psi geometry. XANES provides the possibility for EXAFS, XANES and X-ray fluorescence measurements at-air.

  16. X-ray diffraction from intact tau aggregates in human brain tissue

    Energy Technology Data Exchange (ETDEWEB)

    Landahl, Eric C.; Antipova, Olga; Bongaarts, Angela; Barrea, Raul; Berry, Robert; Binder, Lester I.; Irving, Thomas; Orgel, Joseph; Vana, Laurel; Rice, Sarah E. (DePaul); (IIT); (NWU)

    2011-09-15

    We describe an instrument to record X-ray diffraction patterns from diseased regions of human brain tissue by combining an in-line visible light fluorescence microscope with an X-ray diffraction microprobe. We use thiazine red fluorescence to specifically label and detect the filamentous tau protein pathology associated with Pick's disease, as several laboratories have done previously. We demonstrate that thiazine red-enhanced regions within the tissue show periodic structure in X-ray diffraction, which is not observed in healthy tissue. One observed periodicity (4.2 {angstrom}) is characteristic of cross-beta sheet structure, consistent with previous results from powder diffraction studies performed on purified, dried tau protein.

  17. X-ray diffraction from intact tau aggregates in human brain tissue

    Energy Technology Data Exchange (ETDEWEB)

    Landahl, Eric C. [DePaul University, Department of Physics, 2219 N. Kenmore Ave., IL 60614, Chicago (United States); Antipova, Olga [Illinois Institute of Technology, Department of Biological Chemical and Physical Sciences, 3101 South Dearborn St., IL 60616, Chicago (United States); Bongaarts, Angela [Northwestern University, Department of Cell and Molecular Biology, 303 E. Chicago Ave., IL 60611, Chicago (United States); Barrea, Raul [Illinois Institute of Technology, Department of Biological Chemical and Physical Sciences, 3101 South Dearborn St., IL 60616, Chicago (United States); Berry, Robert; Binder, Lester I. [Northwestern University, Department of Cell and Molecular Biology, 303 E. Chicago Ave., IL 60611, Chicago (United States); Irving, Thomas; Orgel, Joseph [Illinois Institute of Technology, Department of Biological Chemical and Physical Sciences, 3101 South Dearborn St., IL 60616, Chicago (United States); Vana, Laurel [Northwestern University, Department of Cell and Molecular Biology, 303 E. Chicago Ave., IL 60611, Chicago (United States); Rice, Sarah E., E-mail: s-rice@northwestern.edu [Northwestern University, Department of Cell and Molecular Biology, 303 E. Chicago Ave., IL 60611, Chicago (United States)

    2011-09-01

    We describe an instrument to record X-ray diffraction patterns from diseased regions of human brain tissue by combining an in-line visible light fluorescence microscope with an X-ray diffraction microprobe. We use thiazine red fluorescence to specifically label and detect the filamentous tau protein pathology associated with Pick's disease, as several laboratories have done previously. We demonstrate that thiazine red-enhanced regions within the tissue show periodic structure in X-ray diffraction, which is not observed in healthy tissue. One observed periodicity (4.2 A) is characteristic of cross-beta sheet structure, consistent with previous results from powder diffraction studies performed on purified, dried tau protein.

  18. Low-temperature high magnetic field powder x-ray diffraction setup for field-induced structural phase transition studies from 2 to 300 K and at 0 to 8-T field

    Science.gov (United States)

    Shahee, Aga; Sharma, Shivani; Kumar, Dhirendra; Yadav, Poonam; Bhardwaj, Preeti; Ghodke, Nandkishor; Singh, Kiran; Lalla, N. P.; Chaddah, P.

    2016-10-01

    A low-temperature and high magnetic field powder x-ray diffractometer (XRD) has been developed at UGC-DAE CSR (UGC: University Grant Commission, DAE: Department of Atomic Energy, and CSR: Consortium for scientific research), Indore, India. The setup has been developed around an 18 kW rotating anode x-ray source delivering Cu-Kα x-rays coming from a vertical line source. It works in a symmetric θ-2θ parallel beam geometry. It consists of a liquid helium cryostat with an 8 T split-pair Nb-Ti superconducting magnet comprising two x-ray windows each covering an angular range of 65°. This is mounted on a non-magnetic type heavy duty goniometer equipped with all necessary motions along with data collection accessories. The incident x-ray beam has been made parallel using a parabolic multilayer mirror. The scattered x-ray is detected using a NaI detector through a 0.1° acceptance solar collimator. To control the motions of the goniometer, a computer programme has been developed. The wide-angle scattering data can be collected in a range of 2°-115° of 2θ with a resolution of ˜0.1°. The whole setup is tightly shielded for the scattered x-rays using a lead hutch. The functioning of the goniometer and the artifacts arising possibly due to the effect of stray magnetic field on the goniometer motions, on the x-ray source, and on the detector have been characterized by collecting powder XRD data of a National Institute of Standards and Technology certified standard reference material LaB6 (SRM-660b) and Si powder in zero-field and in-field conditions. Occurrence of field induced structural-phase transitions has been demonstrated on various samples like Pr0.5Sr0.5MnO3, Nd0.49Sr0.51MnO3-δ and La0.175Pr0.45Ca0.375MnO3 by collecting data in zero field cool and field cool conditions.

  19. Low-temperature high magnetic field powder x-ray diffraction setup for field-induced structural phase transition studies from 2 to 300 K and at 0 to 8-T field.

    Science.gov (United States)

    Shahee, Aga; Sharma, Shivani; Kumar, Dhirendra; Yadav, Poonam; Bhardwaj, Preeti; Ghodke, Nandkishor; Singh, Kiran; Lalla, N P; Chaddah, P

    2016-10-01

    A low-temperature and high magnetic field powder x-ray diffractometer (XRD) has been developed at UGC-DAE CSR (UGC: University Grant Commission, DAE: Department of Atomic Energy, and CSR: Consortium for scientific research), Indore, India. The setup has been developed around an 18 kW rotating anode x-ray source delivering Cu-Kα x-rays coming from a vertical line source. It works in a symmetric θ-2θ parallel beam geometry. It consists of a liquid helium cryostat with an 8 T split-pair Nb-Ti superconducting magnet comprising two x-ray windows each covering an angular range of 65°. This is mounted on a non-magnetic type heavy duty goniometer equipped with all necessary motions along with data collection accessories. The incident x-ray beam has been made parallel using a parabolic multilayer mirror. The scattered x-ray is detected using a NaI detector through a 0.1° acceptance solar collimator. To control the motions of the goniometer, a computer programme has been developed. The wide-angle scattering data can be collected in a range of 2°-115° of 2θ with a resolution of ∼0.1°. The whole setup is tightly shielded for the scattered x-rays using a lead hutch. The functioning of the goniometer and the artifacts arising possibly due to the effect of stray magnetic field on the goniometer motions, on the x-ray source, and on the detector have been characterized by collecting powder XRD data of a National Institute of Standards and Technology certified standard reference material LaB6 (SRM-660b) and Si powder in zero-field and in-field conditions. Occurrence of field induced structural-phase transitions has been demonstrated on various samples like Pr0.5Sr0.5MnO3, Nd0.49Sr0.51MnO3-δ and La0.175Pr0.45Ca0.375MnO3 by collecting data in zero field cool and field cool conditions.

  20. Nanosecond x-ray Laue diffraction apparatus suitable for laser shock compression experiments.

    Science.gov (United States)

    Suggit, Matthew; Kimminau, Giles; Hawreliak, James; Remington, Bruce; Park, Nigel; Wark, Justin

    2010-08-01

    We have used nanosecond bursts of x-rays emitted from a laser-produced plasma, comprised of a mixture of mid-Z elements, to produce a quasiwhite-light spectrum suitable for performing Laue diffraction from single crystals. The laser-produced plasma emits x-rays ranging in energy from 3 to in excess of 10 keV, and is sufficiently bright for single shot nanosecond diffraction patterns to be recorded. The geometry is suitable for the study of laser-shocked crystals, and single-shot diffraction patterns from both unshocked and shocked silicon crystals are presented.

  1. The Multi-Frame X-ray Diffraction and Imaging Detector at the Dynamic Compression Sector

    Science.gov (United States)

    Sinclair, Nicholas; Wang, Yuxin; Turneaure, Stefan; Zimmerman, Kurt; Toyoda, Yoshi; Gupta, Yogendra

    2017-06-01

    The Dynamic Compression Sector (DCS) at the Advanced Photon Source (APS), located at Argonne National Laboratory, enables x-ray diffraction and imaging measurements on samples during single event, dynamic compression experiments. Since bright x-ray pulses arrive from the synchrotron at a high frequency, `movies' may be captured with these x-ray measurements. However, the ideal detector system capable of these measurements is not yet commercially available and, instead, a composite optical system has been developed to achieve the required time resolution and sensitivity. In this presentation, the current x-ray diffraction and imaging detector system at DCS will be discussed. This system is capable of capturing four frames from x-ray pulses separated by 153 ns -- the pulse separation in the most common APS storage ring mode -- and sensitive enough to capture x-ray powder diffraction patterns from a single 80 ps duration pulse. Several data post-processing issues will be discussed, including the correction of phosphor after-images, determination of sample exposure times with respect to other diagnostics, and spatial distortion correction. Work supported by DOE/NNSA.

  2. Structural studies of tropomyosin by cryoelectron microscopy and x-ray diffraction.

    Science.gov (United States)

    Cabral-Lilly, D; Phillips, G N; Sosinsky, G E; Melanson, L; Chacko, S; Cohen, C

    1991-04-01

    A comparison has been made between cryoelectron microscope images and the x-ray structure of one projection of the Bailey tropomyosin crystal. The computed transforms of the electron micrographs extend to a resolution of approximately 18 A compared with the reflections from x-ray crystallography which extend to 15 A. After correction of the images for lattice distortions and the contrast transfer function, the structure factors were constrained to the plane group (pmg) symmetry of this projection. Amplitude and phase data for five images were compared with the corresponding view from the three-dimensional x-ray diffraction data (Phillips, G.N., Jr., J.P. Fillers, and C. Cohen. 1986. J. Mol. Biol. 192: 111-131). The average R factor between the electron microscopy and x-ray amplitudes was 15%, with an amplitude-weighted mean phase difference of 4.8 degrees. The density maps derived from cryoelectron microscopy contain structural features similar to those from x-ray diffraction: these include the width and run of the filaments and their woven appearance at the crossover regions. Preliminary images obtained from frozen-hydrated tropomyosin/troponin cocrystals suggest that this approach may provide structural details not readily obtainable from x-ray diffraction studies.

  3. Energy-dispersive X-ray diffraction beamline at Indus-2 synchrotron ...

    Indian Academy of Sciences (India)

    Abstract. An energy-dispersive X-ray diffraction beamline has been designed, developed and commissioned at BL-11 bending magnet port of the Indian synchrotron source, Indus-2. The performance of this beamline has been benchmarked by measuring diffraction patterns from var- ious elemental metals and standard ...

  4. Titration of a Solid Acid Monitored by X-Ray Diffraction

    Science.gov (United States)

    Dungey, Keenan E.; Epstein, Paul

    2007-01-01

    An experiment is described to introduce students to an important class of solid-state reactions while reinforcing concepts of titration by using a pH meter and a powder X-ray diffractometer. The experiment was successful in teaching students the abstract concepts of solid-state structure and diffraction by applying the diffraction concepts learned…

  5. Phase analysis study of copper ferrite aluminates by X-ray diffraction and Moessbauer spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Almokhtar, M. E-mail: almoktar@aun.edu.egalmoktar@acc.aun.eun.eg; Abdalla, A.M.Atef M.; Gaffar, M.A

    2004-05-01

    CuFe{sub 2-x}Al{sub x}O{sub 4} (where x=0.0-0.6) have been synthesized at 950 deg. C, 1000 deg. C, 1050 deg. C and 1100 deg. C using the usual ceramic method. The Moessbauer measurements show reasonable values of magnetic as well as electric hyperfine interactions. At higher sintering temperatures, the spinel ferrite phase is partially dissociated forming delafossite phase in addition to the main matrix. The delafossite phase manifested itself as paramagnetic doublet overlapping the main Moessbauer spectra measured at room temperature. Furthermore, X-ray diffraction studies confirmed the presence of the CuFeO{sub 2} (delafossite) phase of Cu-Al ferrite.

  6. In situ x-ray reflectivity and grazing incidence x-ray diffraction study of L 1(0) ordering in (57)Fe/Pt multilayers.

    Science.gov (United States)

    Raghavendra Reddy, V; Gupta, Ajay; Gome, Anil; Leitenberger, Wolfram; Pietsch, U

    2009-05-06

    In situ high temperature x-ray reflectivity and grazing incidence x-ray diffraction measurements in the energy dispersive mode are used to study the ordered face-centered tetragonal (fct) L 1(0) phase formation in [Fe(19 Å)/Pt(25 Å)]( × 10) multilayers prepared by ion beam sputtering. With the in situ x-ray measurements it is observed that (i) the multilayer structure first transforms to a disordered FePt and subsequently to an ordered fct L 1(0) phase, (ii) the ordered fct L 1(0) FePt peaks start to appear at 320 °C annealing, (iii) the activation energy of the interdiffusion is 0.8 eV and (iv) ordered fct FePt grains have preferential out-of-plane texture. The magneto-optical Kerr effect and conversion electron Mössbauer spectroscopies are used to study the magnetic properties of the as-deposited and 400 °C annealed multilayers. The magnetic data for the 400 °C annealed sample indicate that the magnetization is at an angle of ∼50° from the plane of the film.

  7. High-resolution X-ray diffraction imaging of non-Bragg diffracting materials using phase retrieval X-ray diffractometry (PRXRD) technique

    Energy Technology Data Exchange (ETDEWEB)

    Nikulin, A.Y.; Darahanau, A.V.; Horney, R.; Ishikawa, T

    2004-06-15

    An X-ray diffraction technique has recently been developed and successfully applied to comprehensively, including both phase and amplitude contrast, map the complex refractive index of non-crystalline materials with submicron spatial resolution. The methodology is based on the measurement of a high angular resolution X-ray Fraunhofer diffraction pattern with further application of the phase-retrieval formalism using a logarithmic dispersion relation. The technique is reviewed from the perspective of its ability to deliver ultra-high, order of several nanometres, spatial resolution and to uniquely determine both the real and imaginary components of the complex refractive index of the material under analysis. Potential niche of practical applications is discussed in terms of the spatial resolution and field of view achievable by the method.

  8. X-ray Absorption and Diffraction Studies of Thin Polymer/FePt Nanoparticle Assemblies

    Energy Technology Data Exchange (ETDEWEB)

    Toney, Michael F

    2003-06-20

    We have produced assemblies of FePt nanoparticles using high temperature solution phase synthesis and polymer-mediated layer-by-layer deposition allowing precise control of the particle self-assembly. The as-deposited particles have a narrow size distribution offering the potential for use as ultra-high density magnetic storage media and ultimately storage of one bit per individual nanoparticle. Vibrating sample magnetometry was applied to measure the magnetic properties of the particle assemblies as a function of anneal condition while Near Edge X-ray Absorption Fine Structure (NEXAFS) spectroscopy and x-ray diffraction (XRD) were used to investigate the chemical nature and structural properties. It was found that the coercivity can be as high as 22.7 kOe for samples annealed at 800 C, the moment density (normalized to the particle volume) has a maximum of 1140 emu/cm{sup 3} for annealing at 650 C equal to the value for bulk FePt. NEXAFS spectroscopy shows that the Fe in the as-deposited assemblies is partly oxidized, and the oxidation is greatly reduced by annealing. XRD indicates an increased formation of the chemically ordered, high anisotropy L1{sub 0} phase and the onset of nanoparticle agglomeration for annealing at higher temperatures.

  9. Batisite, Na2BaTi2(Si4O12)O2, from Inagli massif, Aldan, Russia: crystal-structure refinement and high-temperature X-ray diffraction study

    Science.gov (United States)

    Zolotarev, Andrey A.; Zhitova, Elena S.; Gabdrakhmanova, Faina A.; Krzhizhanovskaya, Maria G.; Zolotarev, Anatoly A.; Krivovichev, Sergey V.

    2017-12-01

    The crystal structure of batisite, Na2BaTi2 (Si4O12)O2, from the Inagli massif (Aldan, Yakutia, Russia) was refined to R 1 = 0.032 for 1449 unique observed reflections. The mineral is orthorhombic, Imma, a = 8.0921(5), b = 10.4751(7), c = 13.9054(9) Å, V = 1178.70(13) Å3. The mineral is based upon three-dimensional titanosilicate framework consisting of chains of corner-sharing MO6 octahedra ( M = Ti, Nb, Fe and Zr) and vierer chains of corner-sharing SiO4 tetrahedra. Both chains are parallel to the a axis and are linked by sharing peripheral O atoms. The octahedral chains display disorder of M atoms and bridging O sites related to the out-of-center distortion of octahedral geometry around Ti4+ cations. Electron microprobe analysis gives SiO2 39.46, TiO2 24.66, BaO 21.64, Na2O 7.56, K2O 4.38, Fe2O3 0.90, ZrO2 0.66, Nb2O5 0.36, (H2O)calc 0.58, sum 99.76 wt%. The seven strongest X-ray powder-diffraction lines [listed as d in Å (I) hkl] are: 8.39 (94) 011, 3.386 (56) 031, 3.191 (36) 123, 2.910 (46) 222, 2.896 (100) 024, 2.175 (45) 035, 1.673 (57) 055. The thermal behaviour of batisite in the temperature range from 25 to 950 °C was studied using high-temperature powder X-ray diffraction. The thermal expansion coefficients along the principal crystallographic axes are: α a = 14.4 × 10-6, α b = 8.7 × 10-6, α c = 8.4 × 10-6, α V = 31.5 °C-1 for the temperature range 25-500 °C and α a = 19.6 × 10-6, α b = 9.1 × 10-6, α c = 8.8 × 10-6, α V = 37.6 °C-1 for the temperature range 500-900 °C. The direction of maximal thermal expansion is parallel to the chains of both MO6 octahedra and SiO4 tetrahedra, which can be explained by the stretching of silicate chains due to the increasing thermal vibrations of the Ba2+ cations. At 1000 °C, the titanosilicate framework in batisite collapses with the formation of fresnoite, Ba2TiSi2O7O.

  10. Temperature-dependent macromolecular X-ray crystallography

    Energy Technology Data Exchange (ETDEWEB)

    Weik, Martin, E-mail: martin.weik@ibs.fr; Colletier, Jacques-Philippe [CEA, IBS, Laboratoire de Biophysique Moléculaire, F-38054 Grenoble (France); CNRS, UMR5075, F-38027 Grenoble (France); Université Joseph Fourier, F-38000 Grenoble (France)

    2010-04-01

    The dynamical behaviour of crystalline macromolecules and their surrounding solvent as a function of cryo-temperature is reviewed. X-ray crystallography provides structural details of biological macromolecules. Whereas routine data are collected close to 100 K in order to mitigate radiation damage, more exotic temperature-controlled experiments in a broader temperature range from 15 K to room temperature can provide both dynamical and structural insights. Here, the dynamical behaviour of crystalline macromolecules and their surrounding solvent as a function of cryo-temperature is reviewed. Experimental strategies of kinetic crystallography are discussed that have allowed the generation and trapping of macromolecular intermediate states by combining reaction initiation in the crystalline state with appropriate temperature profiles. A particular focus is on recruiting X-ray-induced changes for reaction initiation, thus unveiling useful aspects of radiation damage, which otherwise has to be minimized in macromolecular crystallography.

  11. High temperature GaAs X-ray detectors

    Science.gov (United States)

    Lioliou, G.; Whitaker, M. D. C.; Barnett, A. M.

    2017-12-01

    Two GaAs p+-i-n+ mesa X-ray photodiodes were characterized for their electrical and photon counting X-ray spectroscopic performance over the temperature range of 100 °C to -20 °C. The devices had 10 μm thick i layers with different diameters: 200 μm (D1) and 400 μm (D2). The electrical characterization included dark current and capacitance measurements at internal electric field strengths of up to 50 kV/cm. The determined properties of the two devices were compared with previously reported results that were made with a view to informing the future development of photon counting X-ray spectrometers for harsh environments, e.g., X-ray fluorescence spectroscopy of planetary surfaces in high temperature environments. The best energy resolution obtained (Full Width at Half Maximum at 5.9 keV) decreased from 2.00 keV at 100 °C to 0.66 keV at -20 °C for the spectrometer with D1, and from 2.71 keV at 100 °C to 0.71 keV at -20 °C for the spectrometer with D2. Dielectric noise was found to be the dominant source of noise in the spectra, apart from at high temperatures and long shaping times, where the main source of photopeak broadening was found to be the white parallel noise.

  12. Toward atomic resolution diffractive imaging of isolated molecules with x-ray free-electron lasers

    DEFF Research Database (Denmark)

    Stern, Stephan; Holmegaard, Lotte; Filsinger, Frank

    2014-01-01

    We give a detailed account of the theoretical analysis and the experimental results of an x-ray-diffraction experiment on quantum-state selected and strongly laser-aligned gas-phase ensembles of the prototypical large asymmetric rotor molecule 2,5-diiodobenzonitrile, performed at the Linac Cohere...... Light Source [Phys. Rev. Lett. 112, 083002 (2014)]. This experiment is the first step toward coherent diffractive imaging of structures and structural dynamics of isolated molecules at atomic resolution, i. e., picometers and femtoseconds, using x-ray free-electron lasers.......We give a detailed account of the theoretical analysis and the experimental results of an x-ray-diffraction experiment on quantum-state selected and strongly laser-aligned gas-phase ensembles of the prototypical large asymmetric rotor molecule 2,5-diiodobenzonitrile, performed at the Linac Coherent...

  13. In-laboratory diffraction-enhanced X-ray imaging for articular cartilage.

    Science.gov (United States)

    Muehleman, Carol; Fogarty, Daniel; Reinhart, Benjamin; Tzvetkov, Tochko; Li, Jun; Nesch, Ivan

    2010-07-01

    The loss of articular cartilage characteristic of osteoarthritis can only be diagnosed by joint space narrowing when conventional radiography is used. This is due to the lack of X-ray contrast of soft tissues. Whereas conventional radiography harnesses the X-ray attenuation properties of tissues, Diffraction Enhanced Imaging (DEI), a novel radiographic technique, allows the visualization of soft tissues simultaneous with calcified tissues by virtue of its ability to not only harness X-ray attenuation but also the X-ray refraction from tissue boundaries. Previously, DEI was dependent upon synchrotron X-rays, but more recently, the development of nonsynchrotron DEI units has been explored. These developments serve to elaborate the full potential of radiography. Here, we tested the potential of an in-laboratory DEI system, called Diffraction-Enhanced X-ray Imaging (DEXI), to render images of articular cartilage displaying varying degrees of degradation, ex vivo. DEXI allowed visualization of even early stages of cartilage degeneration such as surface fibrillation. This may be of eventual clinical significance for the diagnosis of early stages of degeneration, or at the very least, to visualize soft tissue degeneration simultaneous with bone changes. (c) 2010 Wiley-Liss, Inc.

  14. Synchrotron Radial X-ray Diffraction Studies of Deformation of Polycrystalline MgO

    Science.gov (United States)

    Girard, J.; Tsujino, N.; Mohiuddin, A.; Karato, S. I.

    2016-12-01

    X-ray diffraction analyses have been used for decades to study mechanical properties of polycrystalline samples during in-situ high-pressure deformation. When polycrystalline materials are deformed, stresses develop in grains and lead to lattice distortion. Using X-ray diffraction we can estimate the lattice strain for each (hkl) diffraction plans and calculate the applied stress for each (hkl), using [Singh, 1993] relation. However, this method doesn't take into account plastic anisotropy. As a results of plastic anisotropy present in the material, stress estimated from this method can be largely differ depending on (hkl) diffraction planes [Karato, 2009]. Studying the stress estimate for each (hkl) plane, might help us distinguish dominant deformation mechanisms activated during deformation such as diffusion (we will observe small stress variation as a function of (hkl) diffraction planes) or dislocation creep (we will observe a stress variation as a function of (hkl) diffraction planes that could also give us clues on potential slip system activity). In this study we observed stress evolution in MgO polycrystalline samples deformed under mantle pressure and temperature for (200) and (220) diffraction planes. Using a range MgO grain sizes we were able to control the active deformation mechanism (for e.g. diffusion creep or dislocation creep). For coarse-grained specimens, we observed strong (hkl) dependence of radial strain indicating the operation of dislocation creep. The observed (hkl) dependence changes with pressure suggesting a change in the slip system: at pressures higher than 27 GPa, (200) shows larger stress estimate than (220). In contrast, at lower pressures, (220) shows larger stress estimate than (200). This might indicate a slip system transition in MgO occurring under lower mantle conditions. From {110} plane to {100} plane. This is in good agreement with theoretical predictions and numerical calculation [Amodeo et al., 2012] and has an important

  15. Electronic properties of crystalline materials observed in X-ray diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Lovesey, S.W. [Diamond Light Source Ltd., ISIS Facility, RAL, Oxfordshire OX11 0QX (United Kingdom) and RIKEN Harima Institute, SPring-8, Hyogo 679-5148 (Japan)]. E-mail: s.w.lovesey@rl.ac.uk; Balcar, E. [Vienna University of Technology, Atominstitut, Stadionallee 2, A1020, Vienna (Austria); Knight, K.S. [Diamond Light Source Ltd., ISIS Facility, RAL, Oxfordshire OX11 0QX (United Kingdom); Department of Mineralogy, Natural History Museum, London SW7 5BD (United Kingdom); Fernandez Rodriguez, J. [Departamento de Fisica, Universidad de Oviedo, E-33007 Oviedo (Spain)

    2005-05-01

    The few electrons in valence states of a material participate in many of its physical properties, including both structural and transport properties. In the diffraction of X-rays, or neutrons, valence electrons can lead to weak Bragg reflections that are extremely sensitive signatures of their charge and magnetic degrees of freedom. In this regard, diffraction instruments supplied with X-rays from a synchrotron source are particularly useful because the brightness, tuneability and polarization of the X-rays are all helpful in making valuable observations. The data obtained from Bragg diffraction can be analyzed on the basis of an atomic model, which has the virtue that it can be used as a common platform for the analysis of X-ray and neutron diffraction and, in addition, the analysis of observations made with X-ray absorption, NMR, EPR, muon and Mossbauer spectroscopies. We present the salient features for the calculation of structure factors based on an atomic model and applied to the analysis of Bragg diffraction by non-magnetic and magnetic materials, with an emphasis on resonant X-ray Bragg diffraction. The presentation contains a new treatment of parity-odd events found in the mixed electric dipole-electric quadrupole channel of scattering. In addition we discuss the complementary observation of dichroic signals, including natural circular and magnetochiral dichroism. The survey of available analytical tools is complemented by a series of worked examples demonstrating the application of the formalism to different materials with different crystal structures and resonant ions: dysprosium borocarbide (DyB{sub 2}C{sub 2}), vanadium sesquioxide (V{sub 2}O{sub 3}), gadolinium tetraboride (GdB{sub 4}), chromium sesquioxide (Cr{sub 2}O{sub 3}), haematite and perovskite-type manganites.

  16. Nano-structured titanium and aluminium nitride coatings: Study by grazing incidence X-ray diffraction and X-ray absorption and anomalous diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Tuilier, M.-H., E-mail: marie-helene.tuilier@uha.fr [Universite de Haute Alsace (UHA), Laboratoire Physique et Mecanique Textile (LPMT), EA 4365 -conventionnee au CNRS, Equipe PPMR, F-68093 Mulhouse (France); Pac, M.-J. [Universite de Haute Alsace (UHA), Laboratoire Physique et Mecanique Textile (LPMT), EA 4365 - conventionnee au CNRS, Equipe PPMR, F-68093 Mulhouse (France); Anokhin, D.V. [Universite de Haute Alsace (UHA), CNRS, Institut de Science des Materiaux de Mulhouse (IS2M), LRC 7228, F-68093 Mulhouse (France); Moscow State University, Faculty of Fundamental Physical and Chemical Engineering, 119991, Moscow, GSP-1, 1-51 Leninskie Gory (Russian Federation); Ivanov, D.A. [Universite de Haute Alsace (UHA), CNRS, Institut de Science des Materiaux de Mulhouse (IS2M), LRC 7228, F-68093 Mulhouse (France); Rousselot, C. [Universite de Franche-Comte, FEMTO-ST (UMR CNRS 6174), F-25211 Montbeliard (France); Thiaudiere, D. [Synchrotron Soleil, Saint Aubin, F-91192 Gif sur Yvette (France)

    2012-12-30

    Titanium and aluminium nitride thin films, Ti{sub 1-x}Al{sub x}N (x = 0, x = 0.5, x = 0.68), deposited by reactive magnetron sputtering on silicon substrates are investigated by combining two different X-ray diffraction experiments carried out using synchrotron radiation. Grazing-incidence X-ray diffraction and Ti K-edge diffraction anomalous near edge structure spectroscopy provide information on the micro- and nano-structure of the films respectively, which play a crucial role in the functionality of coatings. The spectroscopic data of Ti{sub 0.50}Al{sub 0.50}N film show that Ti atoms in crystallized domains and grain boundaries are all in octahedral cubic local order, but their growth mode is quite different. It is found that the crystallized part of the Ti{sub 0.50}Al{sub 0.50}N film has a single-crystalline nature, whereas the TiN one presents a fibrillar microstructure. For Ti{sub 0.32}Al{sub 0.68}N film, grazing-incidence X-ray diffraction provides information on the uniaxial texture along the [001] direction of the hexagonal lattice. A sharp Ti K pre-edge peak is observed in diffraction anomalous near edge spectrum that definitely shows that Ti atoms are incorporated in the hexagonal lattice of those fibrillar domains. Moreover, the difference observed between Ti K-edge diffraction anomalous and X-ray absorption pre-edge regions proves that a significant part of Ti atoms is located in nanocrystallites with cubic symmetry outside of the crystallized domains. - Highlights: Black-Right-Pointing-Pointer We study nano and micro-structures of TiN, Ti{sub 0.50}Al{sub 0.50}N and Ti{sub 0.32}Al{sub 0.68}N films. Black-Right-Pointing-Pointer Anomalous diffraction solves the crystallized part regardless of grain boundaries. Black-Right-Pointing-Pointer TiN microstructure is fibrillar, Ti{sub 0.5}Al{sub 0.5}N presents single crystalline domains. Black-Right-Pointing-Pointer For Ti{sub 0.32}Al{sub 0.68}N, Ti atoms are located in nanocrystallites with cubic symmetry

  17. Coherent x-ray diffraction imaging of paint pigmentparticles by scanning a phase plate modulator

    Energy Technology Data Exchange (ETDEWEB)

    Chu Y. S.; Chen B.; Zhang F.; Berenguer F.; Bean R.; Kewish C.; Vila-Comamala J.; Rodenburg J.; Robinson I.

    2011-10-19

    We have implemented a coherent x-ray diffraction imaging technique that scans a phase plate to modulate wave-fronts of the x-ray beam transmitted by samples. The method was applied to measure a decorative alkyd paint containing iron oxide red pigment particles. By employing an iterative algorithm for wave-front modulation phase retrieval, we obtained an image of the paint sample that shows the distribution of the pigment particles and is consistent with the result obtained from a transmission x-ray microscope. The technique has been experimentally proven to be a feasible coherent x-ray imaging method with about 120 nm spatial resolution and was shown to work well with industrially relevant specimens.

  18. Coherent x-ray diffraction imaging of paint pigment particles by scanning a phase plate modulator

    Science.gov (United States)

    Chen, Bo; Zhang, Fucai; Berenguer, Felisa; Bean, Richard J.; Kewish, Cameron M.; Vila-Comamala, Joan; Chu, Yong S.; Rodenburg, John M.; Robinson, Ian K.

    2011-10-01

    We have implemented a coherent x-ray diffraction imaging technique that scans a phase plate to modulate wave-fronts of the x-ray beam transmitted by samples. The method was applied to measure a decorative alkyd paint containing iron oxide red pigment particles. By employing an iterative algorithm for wave-front modulation phase retrieval, we obtained an image of the paint sample that shows the distribution of the pigment particles and is consistent with the result obtained from a transmission x-ray microscope. The technique has been experimentally proven to be a feasible coherent x-ray imaging method with about 120 nm spatial resolution and was shown to work well with industrially relevant specimens.

  19. Controlled molecules for X-ray diffraction experiments at free-electron lasers

    Energy Technology Data Exchange (ETDEWEB)

    Stern, Stephan

    2013-12-15

    X-ray diffractive imaging is at the very heart of materials science and has been utilized for decades to solve unknown molecular structures. Nowadays, it serves as the key method of structural biology to solve molecular structures of large biological molecules comprising several thousand or even millions of atoms. However, X-ray diffraction from isolated molecules is very weak. Therefore, the regular and periodic arrangement of a huge number of identical copies of a certain molecule of interest within a crystal lattice has been a necessary condition in order to exploit Bragg diffraction of X-rays. This results in a huge increase in scattered signal and a strongly improved signal-to-noise ratio compared to diffraction from non-crystalline samples. The major bottleneck of structural biology is that many of biologically interesting molecules refuse to form crystals of sufficient size to be used at synchrotron X-ray lightsources. However, novel X-ray free-electron lasers (XFELs), which became operational very recently, promise to address this issue. X-ray pulses provided by XFELs are many orders of magnitude more intense than X-ray pulses from a synchrotron source and at the same time as short as only several tens of femtoseconds. Combined with wavelengths in the nm-pm range, XFELs are well-suited to study ultrafast atomic and molecular dynamics. Additionally, the ultrashort pulses can be utilized to circumvent the damage threshold which set a limit to the incident intensity in X-ray diffraction experiments before. At XFELs, though eventually destroying the investigated sample, no significant sample deterioration happens on the ultrashort timescale of the XFEL pulse and the measured diffraction pattern is due to an (almost) unharmed sample. In the framework of this thesis, the approach of utilizing the highly intense XFEL pulses for X-ray diffraction of weakly-scattering non-crystalline samples was taken to the limit of small isolated molecules. X-ray diffraction was

  20. X-ray diffraction imaging with the Multiple Inverse Fan Beam topology: principles, performance and potential for security screening.

    Science.gov (United States)

    Harding, G; Fleckenstein, H; Kosciesza, D; Olesinski, S; Strecker, H; Theedt, T; Zienert, G

    2012-07-01

    The steadily increasing number of explosive threat classes, including home-made explosives (HMEs), liquids, amorphous and gels (LAGs), is forcing up the false-alarm rates of security screening equipment. This development can best be countered by increasing the number of features available for classification. X-ray diffraction intrinsically offers multiple features for both solid and LAGs explosive detection, and is thus becoming increasingly important for false-alarm and cost reduction in both carry-on and checked baggage security screening. Following a brief introduction to X-ray diffraction imaging (XDI), which synthesizes in a single modality the image-forming and material-analysis capabilities of X-rays, the Multiple Inverse Fan Beam (MIFB) XDI topology is described. Physical relationships obtaining in such MIFB XDI components as the radiation source, collimators and room-temperature detectors are presented with experimental performances that have been achieved. Representative X-ray diffraction profiles of threat substances measured with a laboratory MIFB XDI system are displayed. The performance of Next-Generation (MIFB) XDI relative to that of the 2nd Generation XRD 3500TM screener (Morpho Detection Germany GmbH) is assessed. The potential of MIFB XDI, both for reducing the exorbitant cost of false alarms in hold baggage screening (HBS), as well as for combining "in situ" liquid and solid explosive detection in carry-on luggage screening is outlined. Copyright © 2011 Elsevier Ltd. All rights reserved.

  1. X-ray diffraction microscopy based on refractive optics

    DEFF Research Database (Denmark)

    Poulsen, Henning Friis; Jakobsen, A. C.; Simons, Hugh

    2017-01-01

    A formalism is presented for dark‐field X‐ray microscopy using refractive optics. The new technique can produce three‐dimensional maps of lattice orientation and axial strain within millimetre‐sized sampling volumes and is particularly suited to in situ studies of materials at hard X‐ray energies....... An objective lens in the diffracted beam magnifies the image and acts as a very efficient filter in reciprocal space, enabling the imaging of individual domains of interest with a resolution of 100 nm. Analytical expressions for optical parameters such as numerical aperture, vignetting, and the resolution...

  2. X-ray grazing incidence diffraction from multilayers

    Energy Technology Data Exchange (ETDEWEB)

    Tixier, S.; Boeni, P.; Swygenhoven, H. van; Horisberger, M. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1997-09-01

    Grazing incidence scattering geometries using synchrotron radiation have been applied in order to characterise the roughness profiles and the structural coherence of multilayers. The lateral correlation length of the roughness profiles was evaluated using diffuse reflectivity in the `out of plane` geometry. This type of measurement is the only diffuse reflectivity technique allowing large lateral momentum transfer. It is typically suitable for correlation lengths smaller than 1000 A. The lateral structural coherence length of Ni{sub 3}Al/Ni multilayers as a function of the layer thickness was obtained by grazing incidence diffraction (GID). 3 figs., 1 ref.

  3. APPLICATION OF X-RAY DIFFRACTION AND BARKHAUSEN NOISE ANALYSIS FOR STABILITY CONTROL DURING MACHINING

    Directory of Open Access Journals (Sweden)

    Kamil Kolařík

    2011-07-01

    Full Text Available The contribution is focused on the recent experience of X-ray Diffraction Laboratory of the Czech Technical University in Prague and Department of Machining and Assembly of the Technical University of Liberec with industrial applications of X-ray diffraction residual stress measurement and Barkhausen noise analysis. Both methods are used for control and optimization of technological parameters during final surface machining of camshafts. They verify whether the required level of residual stresses in given subsurface areas was achieved and serve also as a fast output inspection of machine parts´ surface quality.

  4. Improved theory of noncomplanar diffraction of X-Rays under specular reflection conditions

    CERN Document Server

    Balyan, M K

    2000-01-01

    In two-wave approximation the equations describing the dynamical diffraction of X-ray spatially modulated waves in ideal and deformed crystals in grazing noncomplanar incidence geometry are obtained. The solutions of obtained equations for diffraction of arbitrary spatially modulated incidence wave in ideal half-infinite crystal are found. As a special case of the obtained solutions, the diffraction of incidence spherical wave under small grazing angle is briefly considered.

  5. Simultaneous X-ray diffraction from multiple single crystals of macromolecules

    DEFF Research Database (Denmark)

    Paithankar, Karthik S.; Sørensen, Henning Osholm; Wright, Jonathan P.

    2011-01-01

    The potential in macromolecular crystallography for using multiple crystals to collect X-ray diffraction data simultaneously from assemblies of up to seven crystals is explored. The basic features of the algorithms used to extract data and their practical implementation are described. The procedu...... could be useful both in relation to diffraction data obtained from intergrown crystals and to alleviate the problem of rapid diffraction decay arising from the effects of radiation damage....

  6. X-ray diffraction in temporally and spatially resolved biomolecular science.

    Science.gov (United States)

    Helliwell, John R; Brink, Alice; Kaenket, Surasak; Starkey, Victoria Laurina; Tanley, Simon W M

    2015-01-01

    Time-resolved Laue protein crystallography at the European Synchrotron Radiation Facility (ESRF) opened up the field of sub-nanosecond protein crystal structure analyses. There are a limited number of such time-resolved studies in the literature. Why is this? The X-ray laser now gives us femtosecond (fs) duration pulses, typically 10 fs up to ∼50 fs. Their use is attractive for the fastest time-resolved protein crystallography studies. It has been proposed that single molecules could even be studied with the advantage of being able to measure X-ray diffraction from a 'crystal lattice free' single molecule, with or without temporal resolved structural changes. This is altogether very challenging R&D. So as to assist this effort we have undertaken studies of metal clusters that bind to proteins, both 'fresh' and after repeated X-ray irradiation to assess their X-ray-photo-dynamics, namely Ta6Br12, K2PtI6 and K2PtBr6 bound to a test protein, hen egg white lysozyme. These metal complexes have the major advantage of being very recognisable shapes (pseudo spherical or octahedral) and thereby offer a start to (probably very difficult) single molecule electron density map interpretations, both static and dynamic. A further approach is to investigate the X-ray laser beam diffraction strength of a well scattering nano-cluster; an example from nature being the iron containing ferritin. Electron crystallography and single particle electron microscopy imaging offers alternatives to X-ray structural studies; our structural studies of crustacyanin, a 320 kDa protein carotenoid complex, can be extended either by electron based techniques or with the X-ray laser representing a fascinating range of options. General outlook remarks concerning X-ray, electron and neutron macromolecular crystallography as well as 'NMR crystallography' conclude the article.

  7. Protegrin interaction with lipid monolayers: Grazing incidence X-ray diffraction and X-ray reflectivity study

    Science.gov (United States)

    Neville, Frances; Ishitsuka, Yuji; Hodges, Chris S.; Konovalov, Oleg; Waring, Alan J.; Lehrer, Robert; Lee, Ka Yee C.; Gidalevitz, David

    2009-01-01

    Interactions of the antimicrobial peptide protegrin-1 (PG-1) with phospholipid monolayers have been investigated by using grazing incidence X-ray diffraction (GIXD) and specular X-ray reflectivity (XR). The structure of a PG-1 film at the air-aqueous interface was also investigated by XR for the first time. Lipid A, dipalmitoyl-phosphatidylglycerol (DPPG) and dipalmitoyl-phosphatidylcholine (DPPC) monolayers were formed at the air-aqueous interface to mimic the surface of the bacterial cell wall and the outer leaflet of the erythrocyte cell membrane, respectively. Experiments were carried out under constant area conditions where the pressure changes upon insertion of peptide into the monolayer. GIXD data suggest that the greatest monolayer disruption produced by PG-1 is seen with the DPPG system at 20 mN/m since the Bragg peaks completely disappear after introduction of PG-1 to the system. PG-1 shows greater insertion into the lipid A system compared to the DPPC system when both films are held at the same initial surface pressure of 20 mN/m. The degree of insertion lessens at 30 mN/m with both DPPC and DPPG monolayer systems. XR data further reveal that PG-1 inserts primarily in the head group region of lipid monolayers. However, only the XR data of the anionic lipids suggest the existence of an additional adsorbed peptide layer below the head group of the monolayer. Overall the data show that the extent of peptide/lipid interaction and lipid monolayer disruption depends not only on the lipid composition of the monolayer, but the packing density of the lipids in the monolayer prior to the introduction of peptide to the subphase. PMID:19672319

  8. XDS: a flexible beamline for X-ray diffraction and spectroscopy at the Brazilian synchrotron.

    Science.gov (United States)

    Lima, F A; Saleta, M E; Pagliuca, R J S; Eleotério, M A; Reis, R D; Fonseca Júnior, J; Meyer, B; Bittar, E M; Souza-Neto, N M; Granado, E

    2016-11-01

    The majority of the beamlines at the Brazilian Synchrotron Light Source Laboratory (LNLS) use radiation produced in the storage-ring bending magnets and are therefore currently limited in the flux that can be used in the harder part of the X-ray spectrum (above ∼10 keV). A 4 T superconducting multipolar wiggler (SCW) was recently installed at LNLS in order to improve the photon flux above 10 keV and fulfill the demands set by the materials science community. A new multi-purpose beamline was then installed at the LNLS using the SCW as a photon source. The XDS is a flexible beamline operating in the energy range between 5 and 30 keV, designed to perform experiments using absorption, diffraction and scattering techniques. Most of the work performed at the XDS beamline concentrates on X-ray absorption spectroscopy at energies above 18 keV and high-resolution diffraction experiments. More recently, new setups and photon-hungry experiments such as total X-ray scattering, X-ray diffraction under high pressures, resonant X-ray emission spectroscopy, among others, have started to become routine at XDS. Here, the XDS beamline characteristics, performance and a few new experimental possibilities are described.

  9. High-temperature behaviour of astrophyllite, K2NaFe7 2+Ti2(Si4O12)2O2(OH)4F: a combined X-ray diffraction and Mössbauer spectroscopic study

    Science.gov (United States)

    Zhitova, Elena S.; Krivovichev, Sergey V.; Hawthorne, Frank C.; Krzhizhanovskaya, Maria G.; Zolotarev, Andrey A.; Abdu, Yassir A.; Yakovenchuk, Viktor N.; Pakhomovsky, Yakov A.; Goncharov, Alexey G.

    2017-09-01

    High-temperature X-ray powder-diffraction study of astrophyllite, K2NaFe7 2+Ti2(Si4O12)2O2(OH)4F, and investigation of the samples annealed at 600 and 700 °C, reveal the occurrence of a phase transformation due to the thermal iron oxidation coupled with (1) deprotonation according to the scheme Fe2+ + OH- → Fe3+ + O2- + ½H2 ↑, and (2) defluorination according to the scheme Fe2+ + F- → Fe3+ + O2-. The phase transformation occurs at 500 °C, it is irreversible and without symmetry changes. The mineral decomposes at 775 °C. Both astrophyllite and its high-temperature dehydroxylated (HT) modification are triclinic, P-1. The unit-cell parameters are a = 5.3752(1), b = 11.8956(3), c = 11.6554(3) Å, α = 113.157(3), β = 94.531(2), γ = 103.112(2)º, V = 655.47(3) Å3 for unheated astrophyllite, and a = 5.3287(4), b = 11.790(1), c = 11.4332(9) Å, α = 112.530(8), β = 94.539(6), γ = 103.683(7)º, V = 633.01(9) Å3 for the HT (annealed) modification of astrophyllite. The oxidation of iron is confirmed: (1) by the presence of an exothermic effect at 584 °C in the DTA/TG curves in an Ar-O atmosphere and its absence in an Ar-Ar atmosphere and (2) by ex situ Mössbauer spectroscopy that showed the oxidation of Fe2+ to Fe3+ in the samples heated to 700 °C. Deprotonation was detected by the evolution of IR spectra in the region 3600-3000 cm-1 for astrophyllite and its HT modification. Defluorination was detected by the presence of F in the electron microprobe analysis of unheated astrophyllite and the absence of F in the analysis of unpolished heated astrophyllite. The significant difference between astrophyllite and its HT modification is in the reduction of the M-O interatomic distances after heating to 500 °C and the distortion indices of the MO6 and Dφ6 octahedra. Thermal behaviour of astrophyllite in the 25-475 °C temperature range can be described as a volume thermal expansion with maximal coefficient of thermal expansion in the direction perpendicular to

  10. Observation of parametric X-ray radiation in an anomalous diffraction region

    Energy Technology Data Exchange (ETDEWEB)

    Alexeyev, V.I., E-mail: vial@x4u.lebedev.ru [P.N. Lebedev Physical Institute RAS, 53 Leninskiy prospect, Moscow (Russian Federation); Belgorod National Research University, 85 Pobedy st., Belgorod (Russian Federation); Eliseyev, A.N., E-mail: elisseev@pluton.lpi.troitsk.ru [P.N. Lebedev Physical Institute RAS, 53 Leninskiy prospect, Moscow (Russian Federation); Belgorod National Research University, 85 Pobedy st., Belgorod (Russian Federation); Irribarra, E., E-mail: esteban.irribarra@epn.edu.ec [Escuela Politécnica Nacional, Ladrón de Guevara E11-253, Quito (Ecuador); Kishin, I.A., E-mail: ivan.kishin@mail.ru [P.N. Lebedev Physical Institute RAS, 53 Leninskiy prospect, Moscow (Russian Federation); Belgorod National Research University, 85 Pobedy st., Belgorod (Russian Federation); Kubankin, A.S., E-mail: kubankin@bsu.edu.ru [P.N. Lebedev Physical Institute RAS, 53 Leninskiy prospect, Moscow (Russian Federation); Belgorod National Research University, 85 Pobedy st., Belgorod (Russian Federation); Nazhmudinov, R.M., E-mail: fizeg@bk.ru [P.N. Lebedev Physical Institute RAS, 53 Leninskiy prospect, Moscow (Russian Federation); Belgorod National Research University, 85 Pobedy st., Belgorod (Russian Federation)

    2016-08-19

    A new possibility to expand the energy region of diffraction processes based on the interaction of relativistic charged particles with crystalline structures is presented. Diffracted photons related to parametric X-ray radiation produced by relativistic electrons are detected below the low energy threshold for the X-ray diffraction mechanism in crystalline structures for the first time. The measurements were performed during the interaction of 7 MeV electrons with a textured polycrystalline tungsten foil and a highly oriented pyrolytic graphite crystal. The experiment results are in good agreement with a developed model based on the PXR kinematical theory. The developed experimental approach can be applied to separate the contributions of real and virtual photons to the total diffracted radiation generated during the interaction of relativistic charged particles with crystalline targets. - Highlights: • Parametric X-ray radiation below the low energy threshold for diffraction of free X-rays. • Experimental separation of the contributions from different radiation mechanisms. • PXR from relativistic electrons in mosaic crystals and textured polycrystlas.

  11. New software to model energy dispersive X-ray diffraction in polycrystalline materials

    Energy Technology Data Exchange (ETDEWEB)

    Ghammraoui, B., E-mail: bahaa.ghammraoui@cea.fr [CEA-Leti, MINATEC Campus, 17 rue des Martyrs, F 38054 Grenoble, Cedex 9 (France); Tabary, J. [CEA-Leti, MINATEC Campus, 17 rue des Martyrs, F 38054 Grenoble, Cedex 9 (France); Pouget, S. [CEA-INAC Sciences de la matieres, 17 rue des Martyrs, F 38054 Grenoble, Cedex 9 (France); Paulus, C.; Moulin, V.; Verger, L. [CEA-Leti, MINATEC Campus, 17 rue des Martyrs, F 38054 Grenoble, Cedex 9 (France); Duvauchelle, Ph. [CNDRI-Insa Lyon, Universite de Lyon, F-69621, Villeurbanne Cedex (France)

    2012-02-01

    Detection of illicit materials, such as explosives or drugs, within mixed samples is a major issue, both for general security and as part of forensic analyses. In this paper, we describe a new code simulating energy dispersive X-ray diffraction patterns in polycrystalline materials. This program, SinFullscat, models diffraction of any object in any diffractometer system taking all physical phenomena, including amorphous background, into account. Many system parameters can be tuned: geometry, collimators (slit and cylindrical), sample properties, X-ray source and detector energy resolution. Good agreement between simulations and experimental data was obtained. Simulations using explosive materials indicated that parameters such as the diffraction angle or the energy resolution of the detector have a significant impact on the diffraction signature of the material inspected. This software will be a convenient tool to test many diffractometer configurations, providing information on the one that best restores the spectral diffraction signature of the materials of interest.

  12. Coded diffraction system in X-ray crystallography using a boolean phase coded aperture approximation

    Science.gov (United States)

    Pinilla, Samuel; Poveda, Juan; Arguello, Henry

    2018-03-01

    Phase retrieval is a problem present in many applications such as optics, astronomical imaging, computational biology and X-ray crystallography. Recent work has shown that the phase can be better recovered when the acquisition architecture includes a coded aperture, which modulates the signal before diffraction, such that the underlying signal is recovered from coded diffraction patterns. Moreover, this type of modulation effect, before the diffraction operation, can be obtained using a phase coded aperture, just after the sample under study. However, a practical implementation of a phase coded aperture in an X-ray application is not feasible, because it is computationally modeled as a matrix with complex entries which requires changing the phase of the diffracted beams. In fact, changing the phase implies finding a material that allows to deviate the direction of an X-ray beam, which can considerably increase the implementation costs. Hence, this paper describes a low cost coded X-ray diffraction system based on block-unblock coded apertures that enables phase reconstruction. The proposed system approximates the phase coded aperture with a block-unblock coded aperture by using the detour-phase method. Moreover, the SAXS/WAXS X-ray crystallography software was used to simulate the diffraction patterns of a real crystal structure called Rhombic Dodecahedron. Additionally, several simulations were carried out to analyze the performance of block-unblock approximations in recovering the phase, using the simulated diffraction patterns. Furthermore, the quality of the reconstructions was measured in terms of the Peak Signal to Noise Ratio (PSNR). Results show that the performance of the block-unblock phase coded apertures approximation decreases at most 12.5% compared with the phase coded apertures. Moreover, the quality of the reconstructions using the boolean approximations is up to 2.5 dB of PSNR less with respect to the phase coded aperture reconstructions.

  13. Two new tensile devices for X-ray diffraction experiments

    Energy Technology Data Exchange (ETDEWEB)

    Freri, N.; Tintori, A.; Depero, L.E.; Sangaletti, L. [Brescia Univ. (Italy); Cernuschi, F.; Ghia, S. [Ente Nazionale per l`Energia Elettrica, Milan (Italy)

    1995-12-01

    Two tensile devices were designed to be used with parallel beam and parafocusing-geometry diffractometers. In thefirst case the device was designed to be attached to a strainflex diffractometer by Rigaku Inc., dedicated to stress analysis and commonly used in metallurgical industry. Since the sample does not move during the measurement, the tensile device can be kept fixed on the experimental table. The device design takes into account the steric hindrance by moving parts of diffractometer. The maximun load that can be applied to the sample is 60.000 N. An attachement to a Siemens D5000 diffractometer with Eulerian cradle has also benn designed for applying a load up tp 6000 N to a sample in the parafocusing-geometry. The installation does not require a re-alignment of the diffractometer. In both cases strain gages were applied to both sides of the specimen for the simultaneous determination of the macroscopic strains. Experiments based on the use of these devices are planned to determine the crystallographic elastic constants and study the influence of the microstructure on the mechanical behaviour of residual stresses in the zone of almost static stresses as well as the influence of residual stresses on uniaxially loaded samples. In addition, by using these devices, it is possible to measure the unstressed d-0 spacings providing useful information in the neutron diffraction study fo stress fields in steel samples.

  14. Cryogenic x-ray diffraction microscopy utilizing high-pressure cryopreservation

    Science.gov (United States)

    Lima, Enju; Chushkin, Yuriy; van der Linden, Peter; Kim, Chae Un; Zontone, Federico; Carpentier, Philippe; Gruner, Sol M.; Pernot, Petra

    2014-10-01

    We present cryo x-ray diffraction microscopy of high-pressure-cryofixed bacteria and report high-convergence imaging with multiple image reconstructions. Hydrated D. radiodurans cells were cryofixed at 200 MPa pressure into ˜10-μm-thick water layers and their unstained, hydrated cellular environments were imaged by phasing diffraction patterns, reaching sub-30-nm resolutions with hard x-rays. Comparisons were made with conventional ambient-pressure-cryofixed samples, with respect to both coherent small-angle x-ray scattering and the image reconstruction. The results show a correlation between the level of background ice signal and phasing convergence, suggesting that phasing difficulties with frozen-hydrated specimens may be caused by high-background ice scattering.

  15. Crystallization kinetics of amorphous griseofulvin by pattern fitting procedure using X-ray diffraction data.

    Science.gov (United States)

    Yamamura, Shigeo; Takahira, Rieko; Momose, Yasunori

    2007-05-01

    A pattern fitting procedure using X-ray powder diffraction patterns was applied to study the crystallization kinetics of amorphous griseofulvin. From the optimized parameters obtained by pattern fitting, a change in the quantity and quality of griseofulvin crystals with crystallization was also investigated. Amorphous griseofulvin was prepared by cooling the melts followed by pulverization. X-ray diffraction patterns of amorphous griseofulvin were repeatedly measured every 20 h. The observed pattern was separated into crystalline diffraction intensity and amorphous scattering intensity by the nonlinear least-squares procedure. The fitting between the observed and simulated diffraction patterns was satisfactorily independent of the degree of crystallinity. Since a good linear relationship was found in a plot of amorphous scattering intensity against crystalline diffraction intensity, the degree of crystallinity can be determined according to Hermans' method. The diffraction peak width increased with higher diffraction angles with crystallization. The crystallization was biphasic: fast and slow crystallization with the growth of low disordered crystals and disordered crystals, respectively. The pattern fitting procedure is a powerful tool to analyze the X-ray diffraction patterns of semicrystalline materials. This procedure can simultaneously analyze the degree of crystallinity and crystal disorder in semicrystalline samples during crystallization.

  16. Optical characterization and x-ray diffraction studies of synthetic ...

    African Journals Online (AJOL)

    ... lime and the resulting calcium chloride solution was reacted with dilute sulphuric acid. Calcinations were done at a constant o temperature of 120 C for a period of four hours. The choice of the production parameters was guided by the findings of previous studies. Optical absorption spectra of the samples were measured ...

  17. A = Rb, K: Single crystal X-ray diffraction studies

    Indian Academy of Sciences (India)

    Unknown

    Abstract. The crystal structure of ferroelastic Rb4Li(HSO4)3(SO4) has been deter- mined at two temperatures, which indicates a structural phase transition, tetragonal. P43 with a = 7⋅629(1) Е , c = 29⋅497(2) Е at 293 K and monoclinic P21 with a = 7⋅583(3) Е , b = 29⋅230(19) Е , c = 7⋅536(5) Е , β = 90⋅14(1)° at 90 K.

  18. Mössbauer effect studies and X-ray diffraction analysis of cobalt ...

    Indian Academy of Sciences (India)

    Unknown

    Abstract. Cobalt ferrite (CoxFe3–xO4) is prepared in powder form by thermal decomposition of iron and cobalt salts and is analysed by X-ray diffraction and Mössbauer spectroscopic techniques. The variation of. Mössbauer parameters, lattice parameters and crystallite size of the products formed with variation in the.

  19. Non-destructive characterization of recrystallization kinetics using three-dimensional X-ray diffraction microscopy

    DEFF Research Database (Denmark)

    Lauridsen, E.M.; Schmidt, Søren; Fæster Nielsen, Søren

    2006-01-01

    Three-dimensional X-ray diffraction (3DXRD) is used to characterize the nucleation and early growth of individual bulk nuclei in situ during recrystallization of 92% cold-rolled copper. It is found that some cube nuclei, but not all, have a significantly faster initial growth than the average...

  20. Analysis of urinary stone constituents using powder X-ray diffraction ...

    Indian Academy of Sciences (India)

    Constituents of urinary stones obtained from various patients from western part of India, which is a highly urinary stone disease-prone area, have been analysed. Eight stones from four patients were collected through urologists and have been analysed using powder X-ray diffraction and FT-IR. Thermogravimetric analysis ...

  1. Synthesis and X-ray diffraction studies of ,, Al2 O3 using aluminium ...

    African Journals Online (AJOL)

    The crystalline particles of the powder obtained were examined by X-ray diffraction, scanning electron microscopy and transmission electron microscopy, while the surface area of the oxide powder was obtained by nitrogen adsorption BET surface area measurement. The result obtained indicated that the -Al2O3 is cubic ...

  2. X-ray diffraction and spectral studies of biological native and modified tissues

    Energy Technology Data Exchange (ETDEWEB)

    Vazina, A.A. [Institute of Theoretical and Experimental Biophysics of RAS, 142290 Pushchino Institutskaya st., 3, Moscow region (Russian Federation)]. E-mail: vazina@iteb.ru; Budantsev, A.Yu. [Institute of Theoretical and Experimental Biophysics of RAS, 142290 Pushchino Institutskaya st., 3, Moscow region (Russian Federation); Bras, W. [DUBBLE-CRG/ESRF, Grenoble (France)] [and others

    2005-05-01

    X-ray diffraction and spectral data obtained by studying different types of native and modified human and animal tissues are reported. It has been found that the proteoglycan structure undergoes transformation upon interaction with calcium cations. The role of the extracellular matrix in the structure of the native tissue is discussed.

  3. High spatial resolution X-ray and gamma ray imaging system using diffraction crystals

    Science.gov (United States)

    Smither, Robert K [Hinsdale, IL

    2011-05-17

    A method and a device for high spatial resolution imaging of a plurality of sources of x-ray and gamma-ray radiation are provided. The device comprises a plurality of arrays, with each array comprising a plurality of elements comprising a first collimator, a diffracting crystal, a second collimator, and a detector.

  4. Positional order in Langmuir monolayers: An X-ray diffraction study

    DEFF Research Database (Denmark)

    Kaganer, V.M.; Brezesinski, G.; Möhwald, H.

    1999-01-01

    The structural phase transition from the hexagonal to a distorted-hexagonal (centered rectangular) phase (the LS-S transition) in Langmuir monolayers of octadecanol is studied in a grazing incidence x-ray diffraction experiment. We find algebraic decay of positional correlations, which suggests...

  5. Structural investigation of porcine stomach mucin by X-ray fiber diffraction and homology modeling

    Energy Technology Data Exchange (ETDEWEB)

    Veluraja, K., E-mail: veluraja@msuniv.ac.in [Department of Physics, Manonmaniam Sundaranar University, Tirunelveli, Tamilnadu 627012 (India); Vennila, K.N. [CAS in Crystallography and Biophysics, University of Madras, Guindy Campus, Chennai, Tamilnadu 600025 (India); Umamakeshvari, K.; Jasmine, A. [Department of Physics, Manonmaniam Sundaranar University, Tirunelveli, Tamilnadu 627012 (India); Velmurugan, D. [CAS in Crystallography and Biophysics, University of Madras, Guindy Campus, Chennai, Tamilnadu 600025 (India)

    2011-03-25

    Research highlights: {yields} Techniques to get oriented mucin fibre. {yields} X-ray fibre diffraction pattern for mucin. {yields} Molecular modeling of mucin based on X-ray fibre diffraction pattern. -- Abstract: The basic understanding of the three dimensional structure of mucin is essential to understand its physiological function. Technology has been developed to achieve orientated porcine stomach mucin molecules. X-ray fiber diffraction of partially orientated porcine stomach mucin molecules show d-spacing signals at 2.99, 4.06, 4.22, 4.7, 5.37 and 6.5 A. The high intense d-spacing signal at 4.22 A is attributed to the antiparallel {beta}-sheet structure identified in the fraction of the homology modeled mucin molecule (amino acid residues 800-980) using Nidogen-Laminin complex structure as a template. The X-ray fiber diffraction signal at 6.5 A reveals partial organization of oligosaccharides in porcine stomach mucin. This partial structure of mucin will be helpful in establishing a three dimensional structure for the whole mucin molecule.

  6. X-ray diffraction results from mars science laboratory: Mineralogy of rocknest at Gale crater

    NARCIS (Netherlands)

    Bish, D.L.; Blake, D.F.; Vaniman, D.T.; Chipera, S.J.; Morris, R.V.; Ming, D.W.; Treiman, A.H.; Sarrazin, P.; Morrison, S.M.; Downs, R.T.; Achilles, C.N.; Yen, A.S.; Bristow, T.F.; Crisp, J.A.; Morookian, J.M.; Farmer, J.D.; Rampe, E.B.; Stolper, E.M.; Spanovich, N.; MSL Science Team, the|info:eu-repo/dai/nl/292012217

    2013-01-01

    The Mars Science Laboratory rover Curiosity scooped samples of soil from the Rocknest aeolian bedform in Gale crater. Analysis of the soil with the Chemistry and Mineralogy (CheMin) x-ray diffraction (XRD) instrument revealed plagioclase (~An57), forsteritic olivine (~Fo62), augite, and pigeonite,

  7. A three-dimensional X-ray diffraction microscope for deformation studies of polycrystals

    DEFF Research Database (Denmark)

    Fæster Nielsen, Søren; Lauridsen, E.M.; Juul Jensen, D.

    2001-01-01

    -dimensional X-ray diffraction (3DXRD) microscope installed at the European Synchrotron Radiation Facility in Grenoble provides a fast and non-destructive technique for mapping the embedded grains within thick samples in three dimensions. All essential features like the position, volume, orientation, stress...

  8. Modelling the X-ray powder diffraction of nitrogen-expanded austenite using the Debye formula

    DEFF Research Database (Denmark)

    Oddershede, Jette; Christiansen, Thomas; Ståhl, Kenny

    2008-01-01

    Stress-free and homogeneous samples of nitrogen-expanded austenite, a defect-rich f.c.c. structure with a high interstitial nitrogen occupancy (between 0.36 and 0.61), have been studied using X-ray powder diffraction and Debye simulations. The simulations confirm the presence of deformation stack...

  9. Localization of ferrocene in NaY zeolite by powder x-ray and neutron diffraction

    NARCIS (Netherlands)

    Kemner, E.; Overweg, A.R.; Van Eijck, L.; Fitch, A.N.; Suard, E.; De Schepper, I.M.; Kearley, G.J.

    2002-01-01

    We study the inclusion of the metallocene ferrocene Fe(C5H5)2 molecules in the supercages of NaY zeolite. To find the exact location of the ferrocene molecules within the supercages we perform neutron and powder x-ray diffraction on bare NaY zeolite, and on NaY zeolite loaded with one or two

  10. Monolayers of CF4 Adsorbed on Graphite, Studied by Synchrotron X-Ray Diffraction

    DEFF Research Database (Denmark)

    Kjær, Kristian; Nielsen, Mourits; Bohr, Jakob

    1982-01-01

    With synchrotron x-ray diffraction we have measured the phase diagram of CF4 monolayers adsorbed on the graphite substrate UCAR-ZYX. We have found four two-dimensional crystalline phases including the 2×2 commensurate structure. Between this and the denser incommensurate hexagonal phase we find...

  11. Mössbauer effect studies and X-ray diffraction analysis of cobalt ...

    Indian Academy of Sciences (India)

    Home; Journals; Bulletin of Materials Science; Volume 26; Issue 5. Mössbauer effect studies and X-ray diffraction analysis of cobalt ferrite prepared in powder form by thermal decomposition method. M D Joseph Sebastian B Rudraswamy M C Radhakrishna Ramani. Magnetic Materials Volume 26 Issue 5 August 2003 pp ...

  12. Origin of nondetectable x-ray diffraction peaks in nanocomposite CuTiZr alloys

    DEFF Research Database (Denmark)

    Jiang, Jianzhong; Kato, H.; Ohsuna, T.

    2003-01-01

    Microscopic structures of Cu60Ti10+xZr30-x (x=0 and 10) alloys have been investigated by transmission electron microscopy, x-ray diffraction (XRD) and differential scanning calorimeter (DSC). In the Cu60Ti10Zr30 samples annealed at 708 K for times ranging from 0 to 130 min, where the enthalpy of ...

  13. An introduction to three-dimensional X-ray diffraction microscopy

    DEFF Research Database (Denmark)

    Poulsen, Henning Friis

    2012-01-01

    penetrating hard X-rays from a synchrotron source and the application of tomographic reconstruction algorithms for the analysis of the diffraction data. In favourable cases, the position, morphology, phase and crystallographic orientation can be derived for up to 1000 elements simultaneously. For each grain...

  14. Mineralogy by X-ray Diffraction on Mars: The Chemin Instrument on Mars Science Laboratory

    Science.gov (United States)

    Vaniman, D. T.; Bristow, T. F.; Bish, D. L.; Ming, D. W.; Blake, D. F.; Morris, R. V.; Rampe, E. B.; Chipera, S. J.; Treiman, A. H.; Morrison, S. M.; hide

    2014-01-01

    To obtain detailed mineralogy information, the Mars Science Laboratory rover Curiosity carries CheMin, the first X-ray diffraction (XRD) instrument used on a planet other than Earth. CheMin has provided the first in situ XRD analyses of full phase assemblages on another planet.

  15. Electrostatic Molecular Interaction from X-ray Diffraction Data. II. Test on Theoretical Pyrazine Data

    NARCIS (Netherlands)

    Feil, Dirk; Moss, Grant

    1983-01-01

    In a previous paper [Moss & Feil (1981). Acta Cryst. A37, 414-421] a method was reported to calculate the electrostatic potential and the electrostatic interaction energy from single-crystal X-ray diffraction data. The method was applied to experimental pyrazine data; however, owing to the

  16. Study of caprine bones after moist and dry heat processes by X-ray diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Barbosa, Caroline M., E-mail: carolmattosb@yahoo.com.br [Instituto de Arqueologia Brasileira (IAB), Belford Roxo, RJ (Brazil); Azeredo, Soraia R.; Lopes, Ricardo T., E-mail: soraia@lin.ufrj.br [Coordenacao dos Programas de Pos-Graduacao em Engenharia (COPPE/LIN/UFRJ), Rio de Janeiro, RJ (Brazil). Laboratorio de Instrumentacao Nuclear; Souza, Sheila M.F.M de, E-mail: sferraz@ensp.fiocruz.br [Fundacao Oswaldo Cruz (ENSP/FIOCRUZ), Rio de Janeiro, RJ (Brazil). Escola Nacional de Saude Publica Sergio Arouca

    2013-07-01

    Bone tissue is a biological material composed of hydroxyapatite (HAp) and collagen matrix. The bone X-ray diffraction (XRD) pattern presents characteristics of the hydroxyapatite crystallography planes. This paper presents the characterization by X-ray diffraction of caprine bone powder pattern and the comparison of this pattern with moist or dry heat cooked bone patterns. The parameters chosen to characterize the X-ray diffraction peaks were: angular position (2θ), full width at half maximumt (FWHM), and relative intensity (I{sub rel}). The X-ray diffraction patterns were obtained with a Shimadzu XRD-6000 diffractometer. The caprine bone XRD pattern revealed a significant correlation of several crystallographic parameters (lattice data) with hydroxyapatite. The profiles of the three bone types analyzed presented differences. The study showed as small angular displacement (decrease of the 2θ angle) of some peaks was observed after moist and dry heat cooking processes. The characterization of bone tissue aimed to contribute to future analysis in the field of archeology. (author)

  17. High-pressure x-ray diffraction of icosahedral Zr-Al-Ni-Cu-Ag quasicrystals

    DEFF Research Database (Denmark)

    Jiang, Jianzhong; Saksl, Karel; Rasmussen, Helge Kildahl

    2001-01-01

    The effect of pressure on the structural stability of icosahedral Zr-Al-Ni-Cu-Ag quasicrystals forming from a Zr65Al7.5Ni10Cu7.5Ag10 metallic glass with a supercooled liquid region of 44 K has been investigated by in situ high-pressure angle-dispersive x-ray powder diffraction at ambient temperat...

  18. Purification, crystallization and preliminary X-ray diffraction experiment of nattokinase from Bacillus subtilis natto

    OpenAIRE

    Yanagisawa, Yasuhide; Chatake, Toshiyuki; Chiba-Kamoshida, Kaori; Naito, Sawa; Ohsugi, Tadanori; Sumi, Hiroyuki; Yasuda, Ichiro; Morimoto, Yukio

    2010-01-01

    Nattokinase, a protein found in high levels in the traditional Japanese food natto, has been reported to have high thrombolytic activity. In the present study, the crystallization of native nattokinase and the collection of X-ray diffraction date from a nattokinase crystal to a resolution of 1.74 Å are reported.

  19. Small angles X-ray diffraction and Mössbauer characterization of ...

    Indian Academy of Sciences (India)

    Abstract. The effect of thermal annealing on the structure and magnetic properties of crystalline Tb/Fe multilayers has been studied using conversion electron Mössbauer spectrometry and small-angle X-ray diffraction. The growth of Tb–Fe amorphous alloy from the interface is observed with increasing annealing ...

  20. A X-ray diffraction analysis on graphene layers of Assam coal

    Indian Academy of Sciences (India)

    The so-called turbostatic structure of carbons in coal with randomly oriented stacking of the lamellae (graphene) produces intense peaks, which are the dominant features in its X-ray diffraction profiles. The diffractogram may be conveniently divided into two regions of reciprocal space, the medium S region (1 < S < 3 Å) and ...

  1. A-DNA and B-DNA: Comparing Their Historical X-Ray Fiber Diffraction Images

    Science.gov (United States)

    Lucas, Amand A.

    2008-01-01

    A-DNA and B-DNA are two secondary molecular conformations (among other allomorphs) that double-stranded DNA drawn into a fiber can assume, depending on the relative water content and other chemical parameters of the fiber. They were the first two forms to be observed by X-ray fiber diffraction in the early 1950s, respectively by Wilkins and…

  2. Synchrotron X-ray diffraction characterization of healthy and fluorotic human dental enamel

    Science.gov (United States)

    Colaço, M. V.; Barroso, R. C.; Porto, I. M.; Gerlach, R. F.; Costa, F. N.; Braz, D.; Droppa, R.; de Sousa, F. B.

    2012-10-01

    With the introduction of fluoride as the main anticaries agent used in preventive dentistry, and perhaps an increase in fluoride in our food chain, dental fluorosis has become an increasing world-wide problem. Visible signs of fluorosis begin to become obvious on the enamel surface as opacities, implying some porosity in the tissue. The mechanisms that conduct the formation of fluorotic enamel are unknown, but should involve modifications in the basic physical-chemistry reactions of demineralization and remineralisation of the enamel of the teeth, which is the same reaction of formation of the enamel's hydroxyapatite (HAp) in the maturation phase. The increase of the amount of fluoride inside of the apatite will result in gradual increase of the lattice parameters. The aim of this work is to characterize the healthy and fluorotic enamel in human tooth using Synchrotron X-ray diffraction. All the scattering profile measurements were carried out at the X-ray diffraction beamline (XRD1) at the Brazilian Synchrotron Light Laboratory—LNLS, Campinas, Brazil. X-ray diffraction experiments were performed both in powder samples and polished surfaces. The powder samples were analyzed to obtain the characterization of a typical healthy enamel pattern. The polished surfaces were analyzed in specific areas that have been identified as fluorotic ones. X-ray diffraction data were obtained for all samples and these data were compared with the control samples and also with the literature data.

  3. Advances in thin film diffraction instrumentation by X-ray optics

    Energy Technology Data Exchange (ETDEWEB)

    Haase, A. [Rich. Seifert and Co., Analytical X-ray Systems, Ahrensburg (Germany)

    1996-09-01

    The structural characterisation of thin films requires a parallel X-ray beam of high intensity. Parallel beam geometry is commonly used in high resolution and single crystal experiments, but also in the field of X-ray diffraction for polycrystalline material (e.g. in phase, texture and stress analysis). For grazing incidence diffraction (GID), the use of small slits on the primary side and of long soller slits with a flat monochromator on the secondary side is standard. New optical elements have been introduced with polychromatic or monochromatic radiation. By means of different applications the results are compared with those of classical beam optics. X-ray fiber optics utilize total external reflection of X-rays on smooth surfaces. Effects of monochromatization are presented. In many fields of application, fiber optics may replace conventional collimators. The use of primary and secondary channel cut crystals can also produce a high parallel monochromatic X-ray beam. A parabolically bent graded multilayer produces a monochromatic parallel beam of high intensity. Compared with classical Bragg-Brentano (focussing) geometry, excellent results have been obtained, especially for samples with an irregular shape. In combination with a channel cut monochromator there is a substantial gain in intensity leading to an increase of the dynamic intensity range of rocking curves.

  4. Graphical method for analyzing wide-angle x-ray diffraction

    Science.gov (United States)

    Chen, XiaoHui; Xue, Tao; Liu, DongBing; Yang, QingGuo; Luo, BinQiang; Li, Mu; Li, XiaoYa; Li, Jun

    2018-01-01

    Wide-angle X-ray diffraction on large-scale laser facility is a well-established experimental method, which is used to study the shock response of single crystal materials by recording X-rays diffracted from numerous lattice planes. We present a three-dimensional graphical method for extracting physical understanding from the raw diffraction data in shocked experiments. This method advances beyond the previous iterative process by turning abstract diffraction theories in shock physics into mathematic issues, providing three-dimensional visualization and quick extraction of data characteristics. The capability and versatility of the method are exhibited by identifying lattice planes for single crystal samples with different orientations and quantitatively measuring the lattice compression and rotation under dynamic loading.

  5. Real Structure and Resudal Stresses in Advanced Welds Determined by X-ray and Neutron Diffraction

    Czech Academy of Sciences Publication Activity Database

    Trojan, K.; Hervoches, Charles; Ganev, N.; Mikula, Pavol; Čapek, J.

    2017-01-01

    Roč. 9, SEP (2017), s. 32-38 E-ISSN 2336-5382 R&D Projects: GA MŠk LM2015056; GA ČR GB14-36566G Institutional support: RVO:61389005 Keywords : laser and MAG welding * residual stresses * X-ray diffraction * neutron diffraction Subject RIV: BM - Solid Matter Physics ; Magnetism https://ojs.cvut.cz/ojs/index.php/APP/article/view/4401/4298

  6. High numerical aperture tabletop soft x-ray diffraction microscopy with 70-nm resolution

    OpenAIRE

    Sandberg, Richard L.; Song, Changyong; Wachulak, Przemyslaw W.; Raymondson, Daisy A.; Paul, Ariel; Amirbekian, Bagrat; Lee, Edwin; Sakdinawat, Anne E.; La-O-Vorakiat, Chan; Marconi, Mario C.; Menoni, Carmen S.; Murnane, Margaret M.; Rocca, Jorge J.; Kapteyn, Henry C.; Miao, Jianwei

    2007-01-01

    Light microscopy has greatly advanced our understanding of nature. The achievable resolution, however, is limited by optical wavelengths to ≈200 nm. By using imaging and labeling technologies, resolutions beyond the diffraction limit can be achieved for specialized specimens with techniques such as near-field scanning optical microscopy, stimulated emission depletion microscopy, and photoactivated localization microscopy. Here, we report a versatile soft x-ray diffraction microscope with 70- ...

  7. Dynamic crystal rotation resolved by high-speed synchrotron X-ray Laue diffraction

    OpenAIRE

    Huang, J.W.; E, J. C.; Huang, J. Y.; Sun, T.; Fezzaa, K.; Luo, S.N.

    2016-01-01

    Dynamic compression experiments are performed on single-crystal Si under split Hopkinson pressure bar loading, together with simultaneous high-speed (250?350?ns resolution) synchrotron X-ray Laue diffraction and phase-contrast imaging. A methodology is presented which determines crystal rotation parameters, i.e. instantaneous rotation axes and angles, from two unindexed Laue diffraction spots. Two-dimensional translation is obtained from dynamic imaging by a single camera. High-speed motion o...

  8. Synchrotron X-ray diffraction imaging studies of dislocations in Kyropoulos grown Ti doped sapphire crystal

    Science.gov (United States)

    Sen, Gourav; Tran Caliste, Thu Nhi; Stelian, Carmen; Baruchel, José; Barthalay, Nicolas; Duffar, Thierry

    2017-06-01

    In this study, X-ray diffraction and X-ray topography, using synchrotron radiation source, were used to analyse the nature of defects in a sapphire single crystal sample grown by Kyropoulos method. Qualitative and quantitative analysis were carried out on the results of the topography experiments. The dislocation density was found to be around 103-104 dislocations/cm2 indicating a crystal of good crystalline quality. Also, the variation of dislocation density with respect to the position on the sample was observed and discussed.

  9. X-ray powder diffraction study of poly/carbon monofluoride/, CF/1.12/

    Science.gov (United States)

    Mahajan, V. K.; Badachhape, R. B.; Margrave, J. L.

    1974-01-01

    Data from X-ray diffraction studies of the poly(carbon monofluoride) with empirical formula CF(1.09-1.15) are reported, and possible intercalation arrangements for the substance are discussed. The data do not conform to true hexagonal symmetry, indicating that the carbon atoms are not coplanar. Each bond angle of carbon is 118.8 deg, and the carbon-carbon distance is 1.47 A. The interlayer distance is 5.76 A. A total absence of (hkl) reflections in the X-ray pattern shows that the separate CF layers are not regularly arranged with respect to one another.

  10. Interaction between Lipid Monolayers and Poloxamer 188: An X-Ray Reflectivity and Diffraction Study

    Science.gov (United States)

    Wu, Guohui; Majewski, Jaroslaw; Ege, Canay; Kjaer, Kristian; Weygand, Markus Jan; Lee, Ka Yee C.

    2005-01-01

    The mechanism by which poloxamer 188 (P188) seals a damaged cell membrane is examined using the lipid monolayer as a model system. X-ray reflectivity and grazing-incidence x-ray diffraction results show that at low nominal lipid density, P188, by physically occupying the available area and phase separating from the lipids, forces the lipid molecules to pack tightly and restore the barrier function of the membrane. Upon compression to bilayer equivalent pressure, P188 is squeezed out from the lipid monolayer, allowing a graceful exit of P188 when the membrane integrity is restored. PMID:16100276

  11. A sample holder for in-house X-ray powder diffraction studies of protein powders

    DEFF Research Database (Denmark)

    Frankær, Christian Grundahl; Harris, Pernille; Ståhl, Kenny

    2011-01-01

    A sample holder for handling samples of protein for in-house X-ray powder diffraction (XRPD) analysis has been made and tested on lysozyme. The use of an integrated pinhole reduced the background, and good signal-to-noise ratios were obtained from only 7 l of sample, corresponding to approximately...... 2-3 mg of dry protein. The sample holder is further adaptable to X-ray absorption spectroscopy (XAS) measurements. Both XRPD and XAS at the Zn K-edge were tested with hexameric Zn insulin....

  12. Ultra-high aspect ratio high-resolution nanofabrication for hard X-ray diffractive optics

    Science.gov (United States)

    Chang, Chieh; Sakdinawat, Anne

    2014-06-01

    Although diffractive optics have played a major role in nanoscale soft X-ray imaging, high-resolution and high-efficiency diffractive optics have largely been unavailable for hard X-rays where many scientific, technological and biomedical applications exist. This is owing to the long-standing challenge of fabricating ultra-high aspect ratio high-resolution dense nanostructures. Here we report significant progress in ultra-high aspect ratio nanofabrication of high-resolution, dense silicon nanostructures using vertical directionality controlled metal-assisted chemical etching. The resulting structures have very smooth sidewalls and can be used to pattern arbitrary features, not limited to linear or circular. We focus on the application of X-ray zone plate fabrication for high-efficiency, high-resolution diffractive optics, and demonstrate the process with linear, circular, and spiral zone plates. X-ray measurements demonstrate high efficiency in the critical outer layers. This method has broad applications including patterning for thermoelectric materials, battery anodes and sensors among others.

  13. A laboratory based system for laue micro x-ray diffraction.

    Science.gov (United States)

    Lynch, P A; Stevenson, A W; Liang, D; Parry, D; Wilkins, S; Tamura, N

    2007-02-01

    A laboratory diffraction system capable of illuminating individual grains in a polycrystalline matrix is described. Using a microfocus x-ray source equipped with a tungsten anode and prefigured monocapillary optic, a micro-x-ray diffraction system with a 10 microm beam was developed. The beam profile generated by the ellipsoidal capillary was determined using the "knife edge" approach. Measurement of the capillary performance, indicated a beam divergence of 14 mrad and a useable energy bandpass from 5.5 to 19 keV. Utilizing the polychromatic nature of the incident x-ray beam and application of the Laue indexing software package X-Ray Micro-Diffraction Analysis Software, the orientation and deviatoric strain of single grains in a polycrystalline material can be studied. To highlight the system potential the grain orientation and strain distribution of individual grains in a polycrystalline magnesium alloy (Mg 0.2 wt % Nd) was mapped before and after tensile loading. A basal (0002) orientation was identified in the as-rolled annealed alloy; after tensile loading some grains were observed to undergo an orientation change of 30 degrees with respect to (0002). The applied uniaxial load was measured as an increase in the deviatoric tensile strain parallel to the load axis.

  14. Crystallization and X-ray diffraction data of Thermus flavus 5S rRNA helices

    Science.gov (United States)

    Vallazza, Marco; Senge, Andrea; Lippmann, Corinna; Perbandt, Markus; Betzel, Christian; Bald, Rolf; Erdmann, Volker A.

    2001-11-01

    5S rRNA is an essential component of the large ribosomal subunit in prokaryotes and eukaryotes. Its unknown function in the ribosome will eventually be revealed in part by structural studies. To promote crystallization and enhance resolution in X-ray diffraction the molecule was subdivided into five domains A-E. Several RNA oligonucleotides were chemically produced by solid-phase phosphoramidite synthesis in order to construct the domains of the 5S rRNA. An improved RNA-MPD-screen was applied in crystallization which covers a complete 2D matrix for the components used. Crystallization analysis resulted in preferred combinations of pH, polyamine, monovalent and divalent cations for short RNA molecules. Six types of crystals corresponding to the domains B, C and E of Thermus flavus 5S rRNA could be obtained which were suitable for X-ray diffraction. Four RNA helices consist of seven base pairs and two of eight base pairs. As special features, they contain two adenines in a bulge position or G : U wobble base pairs assumed to be involved in RNA-protein recognition. With an increase in crystal size an increase in resolution by X-ray analysis was observed. X-ray diffraction data were collected to 1.5 Å resolution using synchrotron radiation and cryogenic cooling techniques.

  15. Rapid, low dose X-ray diffractive imaging of the malaria parasite Plasmodium falciparum

    Energy Technology Data Exchange (ETDEWEB)

    Jones, Michael W.M., E-mail: michael.jones@latrobe.edu.au [ARC Centre of Excellence for Coherent X-Ray Science, Department of Physics, La Trobe University, Victoria 3086 (Australia); Dearnley, Megan K. [ARC Centre of Excellence for Coherent X-Ray Science, Department of Biochemistry and Molecular Biology, Bio21 Institute, The University of Melbourne, Victoria 3010 (Australia); Riessen, Grant A. van [ARC Centre of Excellence for Coherent X-Ray Science, Department of Physics, La Trobe University, Victoria 3086 (Australia); Abbey, Brian [ARC Centre of Excellence for Coherent X-Ray Science, Department of Physics, La Trobe University, Victoria 3086 (Australia); Melbourne Centre for Nanofabrication, Victoria 3168 (Australia); Putkunz, Corey T. [ARC Centre of Excellence for Coherent X-Ray Science, School of Physics, The University of Melbourne, Victoria 3010 (Australia); Junker, Mark D. [ARC Centre of Excellence for Coherent X-Ray Science, Department of Physics, La Trobe University, Victoria 3086 (Australia); Vine, David J. [Advanced Photon Source, Argonne National Laboratory, Argonne, IL 60439 (United States); McNulty, Ian [Advanced Photon Source, Argonne National Laboratory, Argonne, IL 60439 (United States); Centre for Nanoscale Materials, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Nugent, Keith A. [ARC Centre of Excellence for Coherent X-Ray Science, Department of Physics, La Trobe University, Victoria 3086 (Australia); Peele, Andrew G. [ARC Centre of Excellence for Coherent X-Ray Science, Department of Physics, La Trobe University, Victoria 3086 (Australia); Australian Synchrotron, 800 Blackburn Road, Clayton 3168 (Australia); Tilley, Leann [ARC Centre of Excellence for Coherent X-Ray Science, Department of Biochemistry and Molecular Biology, Bio21 Institute, The University of Melbourne, Victoria 3010 (Australia)

    2014-08-01

    Phase-diverse X-ray coherent diffractive imaging (CDI) provides a route to high sensitivity and spatial resolution with moderate radiation dose. It also provides a robust solution to the well-known phase-problem, making on-line image reconstruction feasible. Here we apply phase-diverse CDI to a cellular sample, obtaining images of an erythrocyte infected by the sexual stage of the malaria parasite, Plasmodium falciparum, with a radiation dose significantly lower than the lowest dose previously reported for cellular imaging using CDI. The high sensitivity and resolution allow key biological features to be identified within intact cells, providing complementary information to optical and electron microscopy. This high throughput method could be used for fast tomographic imaging, or to generate multiple replicates in two-dimensions of hydrated biological systems without freezing or fixing. This work demonstrates that phase-diverse CDI is a valuable complementary imaging method for the biological sciences and ready for immediate application. - Highlights: • Phase-diverse coherent X-ray diffraction microscopy provides high-resolution and high-contrast images of intact biological samples. • Rapid nanoscale resolution imaging is demonstrated at orders of magnitude lower dose than previously possible. • Phase-diverse coherent X-ray diffraction microscopy is a robust technique for rapid, quantitative, and correlative X-ray phase imaging.

  16. Energy-windowed, pixellated X-ray diffraction using the Pixirad CdTe detector

    Science.gov (United States)

    O'Flynn, D.; Bellazzini, R.; Minuti, M.; Brez, A.; Pinchera, M.; Spandre, G.; Moss, R.; Speller, R. D.

    2017-01-01

    X-ray diffraction (XRD) is a powerful tool for material identification. In order to interpret XRD data, knowledge is required of the scattering angles and energies of X-rays which interact with the sample. By using a pixellated, energy-resolving detector, this knowledge can be gained when using a spectrum of unfiltered X-rays, and without the need to collimate the scattered radiation. Here we present results of XRD measurements taken with the Pixirad detector and a laboratory-based X-ray source. The cadmium telluride sensor allows energy windows to be selected, and the 62 μm pixel pitch enables accurate spatial information to be preserved for XRD measurements, in addition to the ability to take high resolution radiographic images. Diffraction data are presented for a variety of samples to demonstrate the capability of the technique for materials discrimination in laboratory, security and pharmaceutical environments. Distinct diffraction patterns were obtained, from which details on the molecular structures of the items under study were determined.

  17. Cyclic olefin homopolymer-based microfluidics for protein crystallization and in situ X-ray diffraction

    Science.gov (United States)

    Emamzadah, Soheila; Petty, Tom J.; De Almeida, Victor; Nishimura, Taisuke; Joly, Jacques; Ferrer, Jean-Luc; Halazonetis, Thanos D.

    2009-01-01

    Microfluidics is a promising technology for the rapid iden­tification of protein crystallization conditions. However, most of the existing systems utilize silicone elastomers as the chip material which, despite its many benefits, is highly permeable to water vapour. This limits the time available for protein crystallization to less than a week. Here, the use of a cyclic olefin homopolymer-based microfluidics system for protein crystallization and in situ X-ray diffraction is described. Liquid handling in this system is performed in 2 mm thin transparent cards which contain 500 chambers, each with a volume of 320 nl. Microbatch, vapour-diffusion and free-interface diffusion protocols for protein crystallization were implemented and crystals were obtained of a number of proteins, including chicken lysozyme, bovine trypsin, a human p53 protein containing both the DNA-binding and oligomerization domains bound to DNA and a functionally important domain of Arabidopsis Morpheus’ molecule 1 (MOM1). The latter two polypeptides have not been crystallized previously. For X-ray diffraction analysis, either the cards were opened to allow mounting of the crystals on loops or the crystals were exposed to X-rays in situ. For lysozyme, an entire X-ray diffraction data set at 1.5 Å resolution was collected without removing the crystal from the card. Thus, cyclic olefin homopolymer-based microfluidics systems have the potential to further automate protein crystallization and structural genomics efforts. PMID:19690369

  18. Ultrafast Structural Dynamics by X-Ray Diffraction and Structural Spectroscopy

    Science.gov (United States)

    Weber, Peter M.

    2015-05-01

    The ability to observe molecular reactions in real time is expected to aid the exploration of new reaction mechanisms, the development of catalysts, the understanding of biomolecular processes and the control of chemical reactions and material properties on a molecular level. To reach this goal, we have developed a gas-phase x-ray diffraction experiment that uses the ultrashort x-ray pulses from the Linac Coherent Light Source (LCLS) to capture atomic motions within molecules in a dilute gas (movie'' of the observed dynamics is constructed by comparing ab initio quantum molecular dynamics simulations with the experimental diffraction signal to derive weighted trajectories that provide a good representation of the structural dynamics, with the weighted ensemble of trajectories corresponding to the nuclear flux during the chemical reaction. The x-ray structural data thus provide reaction pathways for which ionization energies can be calculated at each step. We use ultrafast time-resolved multiphoton - ionization photoelectron spectroscopy to measure the travel time required for the molecule to reach certain resonance windows to Rydberg states. By so combining the results from the ultrafast x-ray diffraction with observations from ultrafast (structural) spectroscopy, it appears that we can make significant progress towards the ultimate goal: a comprehensive understanding of the spatially resolved photochemical reaction dynamics.

  19. EXAFS and X-ray diffraction study of LaCoO3 across the spin-state transition

    Science.gov (United States)

    Sikolenko, V. V.; Troyanchuk, I. O.; Efimov, V. V.; Efimova, E. A.; Tiutiunnikov, S. I.; Karpinsky, D. V.; Pascarelli, S.; Zaharko, O.; Ignatov, A.; Aquilanti, D.; Selutin, A. G.; Shmakov, A. N.; Prabhakaran, D.

    2016-05-01

    A combined high-resolution Co K-edge extended x-ray absorption fine structure (EXAFS) and high-resolution X-ray powder diffraction (XRD) study has been performed to clarify the detail of anomalous behavior of temperature-dependent magnetic susceptibility curve on the LaCoO3 across the spin-state (∼120 K) transition. According to XRD analysis, the Debye-Waller factor of Co-O bond exhibit rapid growth below 20 K whereas the temperature dependence of the average Co-O bond length shows linear behavior from 10 K to 400 K. The EXAFS data show an anomalous decrease of the Co-O bond lengths with respect to those obtained by XRD. No local distortion of CoO6 octahedral as temperature increases up to 400 K has been detected.

  20. Analytical characterization of a new mobile X-ray fluorescence and X-ray diffraction instrument combined with a pigment identification case study

    Energy Technology Data Exchange (ETDEWEB)

    Van de Voorde, Lien, E-mail: lien.vandevoorde@ugent.be [Ghent University, Department of Analytical Chemistry, X-ray Microspectroscopy and Imaging Research Group, Krijgslaan 281 S12, B-9000 Gent (Belgium); Vekemans, Bart [Ghent University, Department of Analytical Chemistry, X-ray Microspectroscopy and Imaging Research Group, Krijgslaan 281 S12, B-9000 Gent (Belgium); Verhaeven, Eddy [Antwerp University, Faculty of Design Sciences, Mutsaardstraat 31, B-2000 Antwerpen (Belgium); Tack, Pieter; De Wolf, Robin; Garrevoet, Jan [Ghent University, Department of Analytical Chemistry, X-ray Microspectroscopy and Imaging Research Group, Krijgslaan 281 S12, B-9000 Gent (Belgium); Vandenabeele, Peter [Ghent University, Department of Archaeology, Archaeometry Research Group, Sint-Pietersnieuwstraat 35, B-9000 Gent (Belgium); Vincze, Laszlo [Ghent University, Department of Analytical Chemistry, X-ray Microspectroscopy and Imaging Research Group, Krijgslaan 281 S12, B-9000 Gent (Belgium)

    2015-08-01

    A new, commercially available, mobile system combining X-ray diffraction and X-ray fluorescence has been evaluated which enables both elemental analysis and phase identification simultaneously. The instrument makes use of a copper or molybdenum based miniature X-ray tube and a silicon-Pin diode energy-dispersive detector to count the photons originating from the samples. The X-ray tube and detector are both mounted on an X-ray diffraction protractor in a Bragg–Brentano θ:θ geometry. The mobile instrument is one of the lightest and most compact instruments of its kind (3.5 kg) and it is thus very useful for in situ purposes such as the direct (non-destructive) analysis of cultural heritage objects which need to be analyzed on site without any displacement. The supplied software allows both the operation of the instrument for data collection and in-depth data analysis using the International Centre for Diffraction Data database. This paper focuses on the characterization of the instrument, combined with a case study on pigment identification and an illustrative example for the analysis of lead alloyed printing letters. The results show that this commercially available light-weight instrument is able to identify the main crystalline phases non-destructively, present in a variety of samples, with a high degree of flexibility regarding sample size and position. - Highlights: • New X-ray fluorescence and X-ray diffraction instrument for non-destructive analysis • Commercially available, mobile system • One of the lightest and most compact of its kind • Characterization, data acquisition and analysis are performed. • Results of measurements on pigment model samples and cultural heritage materials.

  1. Imaging of Biological Materials and Cells by X-ray Scattering and Diffraction.

    Science.gov (United States)

    Hémonnot, Clément Y J; Köster, Sarah

    2017-09-26

    Cells and biological materials are large objects in comparison to the size of internal components such as organelles and proteins. An understanding of the functions of these nanoscale elements is key to elucidating cellular function. In this review, we describe the advances in X-ray scattering and diffraction techniques for imaging biological systems at the nanoscale. We present a number of principal technological advances in X-ray optics and development of sample environments. We identify radiation damage as one of the most severe challenges in the field, thus rendering the dose an important parameter when putting different X-ray methods in perspective. Furthermore, we describe different successful approaches, including scanning and full-field techniques, along with prominent examples. Finally, we present a few recent studies that combined several techniques in one experiment in order to collect highly complementary data for a multidimensional sample characterization.

  2. Double-slit dynamical diffraction of X-rays in ideal crystals (Laue case).

    Science.gov (United States)

    Balyan, Minas K

    2010-11-01

    The theoretical investigation of double-slit dynamical X-ray diffraction in ideal crystals shows that, on the exit surface of crystals, interference fringes similar to Young's fringes are formed. An expression for the period of the fringes was obtained. The visibility of the fringes depending on temporal and spatial coherent properties of the incident beam is studied. The polarization state of the incident beam also affects the visibility of the fringes, which in turn depends on the size of the slits. The deviation from Bragg's exact angle causes a shift of the fringes and can also affect the amplitude of the intensity. One of the parameters on which the visibility of the fringes depends is the source-crystal distance. The proposed scheme can be used as a Rayleigh X-ray interferometer. Use of the scheme as a Michelson X-ray stellar interferometer is also possible.

  3. Disputed discovery: the beginnings of X-ray diffraction in crystals in 1912 and its repercussions.

    Science.gov (United States)

    Eckert, Michael

    2012-01-01

    The discovery of X-ray diffraction is reviewed from the perspective of the contemporary knowledge in 1912 about the nature of X-rays. Laue's inspiration that led to the experiments by Friedrich and Knipping in Sommerfeld's institute was based on erroneous expectations. The ensuing discoveries of the Braggs clarified the phenomenon (although they, too, emerged from dubious assumptions about the nature of X-rays). The early misapprehensions had no impact on the Nobel Prizes to Laue in 1914 and the Braggs in 1915; but when the prizes were finally awarded after the war, the circumstances of `Laue's discovery' gave rise to repercussions. Many years later, they resulted in a dispute about the `myths of origins' of the community of crystallographers.

  4. Cyclic olefin homopolymer-based microfluidics for protein crystallization and in situ X-ray diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Emamzadah, Soheila [Department of Molecular Biology, University of Geneva, CH-1205 Geneva (Switzerland); Department of Biochemistry, University of Geneva, CH-1205 Geneva (Switzerland); Petty, Tom J. [Department of Molecular Biology, University of Geneva, CH-1205 Geneva (Switzerland); Biomedical Graduate Studies Genomics and Computational Biology Group, University of Pennsylvania, Philadelphia, PA 19104 (United States); De Almeida, Victor [Department of Molecular Biology, University of Geneva, CH-1205 Geneva (Switzerland); Department of Biochemistry, University of Geneva, CH-1205 Geneva (Switzerland); Nishimura, Taisuke [Department of Plant Biology, University of Geneva, CH-1205 Geneva (Switzerland); Joly, Jacques; Ferrer, Jean-Luc [Institut de Biologie Structurale J.-P. Ebel, CEA-CNRS-University J. Fourier, 38027 Grenoble CEDEX 1 (France); Halazonetis, Thanos D., E-mail: thanos.halazonetis@unige.ch [Department of Molecular Biology, University of Geneva, CH-1205 Geneva (Switzerland); Department of Biochemistry, University of Geneva, CH-1205 Geneva (Switzerland)

    2009-09-01

    A cyclic olefin homopolymer-based microfluidics system has been established for protein crystallization and in situ X-ray diffraction. Microfluidics is a promising technology for the rapid identification of protein crystallization conditions. However, most of the existing systems utilize silicone elastomers as the chip material which, despite its many benefits, is highly permeable to water vapour. This limits the time available for protein crystallization to less than a week. Here, the use of a cyclic olefin homopolymer-based microfluidics system for protein crystallization and in situ X-ray diffraction is described. Liquid handling in this system is performed in 2 mm thin transparent cards which contain 500 chambers, each with a volume of 320 nl. Microbatch, vapour-diffusion and free-interface diffusion protocols for protein crystallization were implemented and crystals were obtained of a number of proteins, including chicken lysozyme, bovine trypsin, a human p53 protein containing both the DNA-binding and oligomerization domains bound to DNA and a functionally important domain of Arabidopsis Morpheus’ molecule 1 (MOM1). The latter two polypeptides have not been crystallized previously. For X-ray diffraction analysis, either the cards were opened to allow mounting of the crystals on loops or the crystals were exposed to X-rays in situ. For lysozyme, an entire X-ray diffraction data set at 1.5 Å resolution was collected without removing the crystal from the card. Thus, cyclic olefin homopolymer-based microfluidics systems have the potential to further automate protein crystallization and structural genomics efforts.

  5. In situ flow cell for combined X-ray absorption spectroscopy, X-ray diffraction, and mass spectrometry at high photon energies under solar thermochemical looping conditions

    Science.gov (United States)

    Rothensteiner, Matthäus; Jenni, Joel; Emerich, Hermann; Bonk, Alexander; Vogt, Ulrich F.; van Bokhoven, Jeroen A.

    2017-08-01

    An in situ/operando flow cell for transmission mode X-ray absorption spectroscopy (XAS), X-ray diffraction (XRD), and combined XAS/XRD measurements in a single experiment under the extreme conditions of two-step solar thermochemical looping for the dissociation of water and/or carbon dioxide was developed. The apparatus exposes materials to relevant conditions of both the auto-reduction and the oxidation sub-steps of the thermochemical cycle at ambient temperature up to 1773 K and enables determination of the composition of the effluent gases by online quadrupole mass spectrometry. The cell is based on a tube-in-tube design and is heated by means of a focusing infrared furnace. It was tested successfully for carbon dioxide splitting. In combined XAS/XRD experiments with an unfocused beam, XAS measurements were performed at the Ce K edge (40.4 keV) and XRD measurements at 64.8 keV and 55.9 keV. Furthermore, XRD measurements with a focused beam at 41.5 keV were carried out. Equimolar ceria-hafnia was auto-reduced in a flow of argon and chemically reduced in a flow of hydrogen/helium. Under reducing conditions, all cerium(iv) was converted to cerium(iii) and a cation-ordered pyrochlore-type structure was formed, which was not stable upon oxidation in a flow of carbon dioxide.

  6. X-RAY DEBYE TEMPERATURE STUDY OF Fe2O3 NANOPARTICLES

    OpenAIRE

    L.Jithender; N Gopi Krishna

    2012-01-01

    Fe2O3 nanoparticle powders have been prepared by a chemical route synthesis. The resulting nanoparticle powders were characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM). The Debye temperature, mean-square amplitudes of vibration, Debye-Waller factor, particle size, lattice strain, and vacancy formation of energies of Fe2O3 nanoparticles prepared by chemical route synthesis have been obtained from Xray integrated intensities. The integrated intensities have been mea...

  7. Artificial Temperature Anisotropy of Crystals in X-Ray Frequency Range

    Science.gov (United States)

    Mkrtchyan, Vahram P.; Gasparyan, Laura G.; Balyan, Minas K.

    2010-04-01

    The effect of artificial temperature anisotropy of crystals in X-ray frequency range was observed for the first time and an effort to theoretically interpret this effect in Bragg-Laue diffraction case was made. It was established that an isotropic crystal optically turns into an artificially anisotropic one with optical axis along the direction of applied external influence as a symmetry axis, giving rise to the double refraction.

  8. Crystallization and preliminary X-ray diffraction analysis of restriction endonuclease EcoRII

    Science.gov (United States)

    Karpova, E. A.; Meehan, E.; Pusey, M. L.; Chen, L.

    1999-01-01

    Crystals of the restriction endonuclease EcoRII have been obtained by the vapor-diffusion technique in the presence of ammonium sulfate or polyethylene glycol. The best crystals were grown with ammonium sulfate as a precipitant. Crystals with dimensions of up to 0.6 x 0. 6 x 0.6 mm have been observed. The crystals diffract to about 4.0 A resolution at a cryo-temperature of 100 K using a rotating-anode X-ray source and a Rigaku R-AXIS IV imaging-plate detector. The space group has been determined to be either I23 or I2(1)3, with unit-cell parameters a = b = c = 160.3 A, alpha = beta = gamma = 90 degrees. The crystal asymmetric unit contains two protein molecules, and self-rotation function analysis shows a pseudo-twofold symmetry relating the two monomers. Attempts to improve the resolution of crystal diffraction and to search for heavy-atom derivatives are under way.

  9. Purification, crystallization and preliminary X-ray diffraction experiment of nattokinase from Bacillus subtilis natto.

    Science.gov (United States)

    Yanagisawa, Yasuhide; Chatake, Toshiyuki; Chiba-Kamoshida, Kaori; Naito, Sawa; Ohsugi, Tadanori; Sumi, Hiroyuki; Yasuda, Ichiro; Morimoto, Yukio

    2010-12-01

    Nattokinase is a single polypeptide chain composed of 275 amino acids (molecular weight 27,724) which displays strong fibrinolytic activity. Moreover, it can activate other fibrinolytic enzymes such as pro-urokinase and tissue plasminogen activator. In the present study, native nattokinase from Bacillus subtilis natto was purified using gel-filtration chromatography and crystallized to give needle-like crystals which could be used for X-ray diffraction experiments. The crystals belonged to space group C2, with unit-cell parameters a=74.3, b=49.9, c=56.3 Å, β=95.2°. Diffraction images were processed to a resolution of 1.74 Å with an Rmerge of 5.2% (15.3% in the highest resolution shell) and a completeness of 69.8% (30.0% in the highest resolution shell). This study reports the first X-ray diffraction analysis of nattokinase.

  10. Rosalind Franklin's X-ray photo of DNA as an undergraduate optical diffraction experiment

    Science.gov (United States)

    Thompson, J.; Braun, G.; Tierney, D.; Wessels, L.; Schmitzer, H.; Rossa, B.; Wagner, H. P.; Dultz, W.

    2018-02-01

    Rosalind Franklin's X-ray diffraction patterns of DNA molecules rendered the important clue that DNA has the structure of a double helix. The most famous X-ray photograph, Photo 51, is still printed in most Biology textbooks. We suggest two optical experiments for undergraduates that make this historic achievement comprehensible for students by using macromodels of DNA and visible light to recreate a diffraction pattern similar to Photo 51. In these macromodels, we replace the double helix both mathematically and experimentally with its two-dimensional (flat) projection and explain why this is permissible. Basic optical concepts are used to infer certain well-known characteristics of DNA from the diffraction pattern.

  11. Correct interpretation of diffraction properties of quartz crystals for X-ray optics applications

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Xian-Rong; Gog, Thomas; Kim, Jungho; Kasman, Elina; Said, Ayman H.; Casa, Diego M.; Wieczorek, Michael; Hönnicke, Marcelo G.; Assoufid, Lahsen

    2018-02-01

    Quartz has hundreds of strong Bragg reflections that may offer a great number of choices for making fixed-angle X-ray analyzers and polarizers at virtually any hard X-ray energies with selectable resolution. However, quartz crystals, unlike silicon and germanium, are chiral and may thus appear in two different forms of handedness that are mirror images. Furthermore, because of the threefold rotational symmetry along thecaxis, the {h1h2h3L} and {h2h1h3L} Bragg reflections may have quite different Darwin bandwidth, reflectivity and angular acceptance, although they have the same Bragg angle. The design of X-ray optics from quartz crystals therefore requires unambiguous determination of the orientation, handedness and polarity of the crystals. The Laue method and single-axis diffraction technique can provide such information, but the variety of conventions used in the literature to describe quartz structures has caused widespread confusion. The current studies give detailed guidelines for design and fabrication of quartz X-ray optics, with special emphasis on the correct interpretation of Laue patterns in terms of the crystallography and diffraction properties of quartz. Meanwhile, the quartz crystals examined were confirmed by X-ray topography to have acceptably low densities of dislocations and other defects, which is the foundation for developing high-resolution quartz-based X-ray optics.

  12. JMFA2—a graphically interactive Java program that fits microfibril angle X-ray diffraction data

    Science.gov (United States)

    Steve P. Verrill; David E. Kretschmann; Victoria L. Herian

    2006-01-01

    X-ray diffraction techniques have the potential to decrease the time required to determine microfibril angles dramatically. In this paper, we discuss the latest version of a curve-fitting toll that permits us to reduce the time required to evaluate MFA X-ray diffraction patterns. Further, because this tool reflects the underlying physics more accurately than existing...

  13. Nano-Second Time-Resolved Synchrotron X-Ray Diffraction Study of Olivine Under Laser-induced Shock Compression

    Science.gov (United States)

    Mikouchi, T.; Ohsumi, K.; Ichiyanagi, K.; Adachi, S.; Nozawa, S.; Koshihara, S.; Zolensky, M.

    2009-03-01

    We performed in-situ nano-second time-resolved synchrotron X-ray diffraction analysis of olivine by synchronization of X-ray and laser pulses. We could successfully obtain 0-30 ns Laue diffraction images at the shock pressure of 1.2-6.5 GPa.

  14. Preliminary small-angle X-ray scattering and X-ray diffraction studies of the BTB domain of lola protein from Drosophila melanogaster

    Science.gov (United States)

    Boyko, K. M.; Nikolaeva, A. Yu.; Kachalova, G. S.; Bonchuk, A. N.; Dorovatovskii, P. V.; Popov, V. O.

    2017-11-01

    The Drosophila genome has several dozens of transcription factors (TTK group) containing BTB domains assembled into octamers. The LOLA protein belongs to this family. The purification, crystallization, and preliminary X-ray diffraction and small-angle X-ray scattering (SAXS) studies of the BTB domain of this protein are reported. The crystallization conditions were found by the vapor-diffusion technique. A very low diffraction resolution (8.7 Å resolution) of the crystals was insufficient for the determination of the threedimensional structure of the BTB domain. The SAXS study demonstrated that the BTB domain of the LOLA protein exists as an octamer in solution.

  15. Structure of organoclays--an X-ray diffraction and thermogravimetric analysis study.

    Science.gov (United States)

    Xi, Yunfei; Ding, Zhe; He, Hongping; Frost, Ray L

    2004-09-01

    X-ray diffraction has been used to study the changes in the surface properties of a montmorillonitic clay through the changes in the basal spacings of montmorillonite (SWy-2) and surfactant-intercalated organoclays. Variation in the d-spacing was found to be a step function of the surfactant concentration. High-resolution thermogravimetric analysis (HRTG) shows that the thermal decomposition of SWy-2-MMTs modified with the surfactant octadecyltrimethylammonium bromide takes place in four steps. A mass-loss step is observed at room temperature and is attributed to dehydration of adsorption water. A second mass-loss step is observed over the temperature range 87.9 to 135.5 degrees C and is also attributed to dehydration of water hydrating metal cations such as Na+. The third mass loss occurs from 178.9 to 384.5 degrees C and is assigned to a loss of surfactant. The fourth mass-loss step is ascribed to the loss of OH units through dehydroxylation over the temperature range 556.0 to 636.4 degrees C. A model is proposed in which, up to 0.4 CEC, a surfactant monolayer is formed between the montmorillonitic clay layers; up to 0.8 CEC, a lateral-bilayer arrangement is formed; and above 1.5 CEC, a pseudotrimolecular layer is formed, with excess surfactant adsorbed on the clay surface.

  16. An X-ray diffraction analysis of crystallised whey and whey-permeate powders.

    Science.gov (United States)

    Nijdam, Justin; Ibach, Alexander; Eichhorn, Klaus; Kind, Matthias

    2007-11-26

    Amorphous whey, whey-permeate and lactose powders have been crystallised at various air temperatures and humidities, and these crystallised powders have been examined using X-ray diffraction. The most stable lactose crystal under normal storage conditions, alpha-lactose monohydrate, forms preferentially in whey and whey-permeate powders at 50 degrees C, provided sufficient moisture is available, whereas anhydrous beta-lactose and mixed anhydrous lactose crystals, which are unstable under normal storage conditions, form preferentially at 90 degrees C. Thus, faster crystallisation at higher temperatures is offset by the formation of lactose-crystal forms that are less stable under normal storage conditions. Very little alpha-lactose monohydrate crystallised in the pure lactose powders over the range of temperatures and humidities tested, because the crystallisation of alpha- and beta-lactose is considerably more rapid than the mutarotation of beta- to alpha-lactose in the amorphous phase and the hydration of alpha-lactose during crystallisation. Protein and salts hinder the crystallisation process, which provides more time for mutarotation and crystal hydration in the whey and whey-permeate powders.

  17. Analytical characterization of a new mobile X-ray fluorescence and X-ray diffraction instrument combined with a pigment identification case study

    Science.gov (United States)

    Van de Voorde, Lien; Vekemans, Bart; Verhaeven, Eddy; Tack, Pieter; De Wolf, Robin; Garrevoet, Jan; Vandenabeele, Peter; Vincze, Laszlo

    2015-08-01

    A new, commercially available, mobile system combining X-ray diffraction and X-ray fluorescence has been evaluated which enables both elemental analysis and phase identification simultaneously. The instrument makes use of a copper or molybdenum based miniature X-ray tube and a silicon-Pin diode energy-dispersive detector to count the photons originating from the samples. The X-ray tube and detector are both mounted on an X-ray diffraction protractor in a Bragg-Brentano θ:θ geometry. The mobile instrument is one of the lightest and most compact instruments of its kind (3.5 kg) and it is thus very useful for in situ purposes such as the direct (non-destructive) analysis of cultural heritage objects which need to be analyzed on site without any displacement. The supplied software allows both the operation of the instrument for data collection and in-depth data analysis using the International Centre for Diffraction Data database. This paper focuses on the characterization of the instrument, combined with a case study on pigment identification and an illustrative example for the analysis of lead alloyed printing letters. The results show that this commercially available light-weight instrument is able to identify the main crystalline phases non-destructively, present in a variety of samples, with a high degree of flexibility regarding sample size and position.

  18. Coherent convergent-beam time-resolved X-ray diffraction.

    Science.gov (United States)

    Spence, John C H; Zatsepin, Nadia A; Li, Chufeng

    2014-07-17

    The use of coherent X-ray lasers for structural biology allows the use of nanometre diameter X-ray beams with large beam divergence. Their application to the structure analysis of protein nanocrystals and single particles raises new challenges and opportunities. We discuss the form of these coherent convergent-beam (CCB) hard X-ray diffraction patterns and their potential use for time-resolved crystallography, normally achieved by Laue (polychromatic) diffraction, for which the monochromatic laser radiation of a free-electron X-ray laser is unsuitable. We discuss the possibility of obtaining single-shot, angle-integrated rocking curves from CCB patterns, and the dependence of the resulting patterns on the focused beam coordinate when the beam diameter is larger or smaller than a nanocrystal, or smaller than one unit cell. We show how structure factor phase information is provided at overlapping interfering orders and how a common phase origin between different shots may be obtained. Their use in refinement of the phase-sensitive intensity between overlapping orders is suggested. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  19. X-ray plane-wave diffraction effects in a crystal with third-order nonlinearity

    Energy Technology Data Exchange (ETDEWEB)

    Balyan, M. K., E-mail: mbalyan@ysu.am [Yerevan State University, Faculty of Physics (Armenia)

    2016-12-15

    The two-wave dynamical diffraction in the Laue geometry has been theoretically considered for a plane X-ray wave in a crystal with a third-order nonlinear response to the external field. An analytical solution to the problem stated is found for certain diffraction conditions. A nonlinear pendulum effect is analyzed. The nonlinear extinction length is found to depend on the incident-wave intensity. A pendulum effect of a new type is revealed: the intensities of the transmitted and diffracted waves periodically depend on the incidentwave intensity at a fixed crystal thickness. The rocking curves and Borrmann nonlinear effect are numerically calculated.

  20. Dynamic crystal rotation resolved by high-speed synchrotron X-ray Laue diffraction.

    Science.gov (United States)

    Huang, J W; E, J C; Huang, J Y; Sun, T; Fezzaa, K; Luo, S N

    2016-05-01

    Dynamic compression experiments are performed on single-crystal Si under split Hopkinson pressure bar loading, together with simultaneous high-speed (250-350 ns resolution) synchrotron X-ray Laue diffraction and phase-contrast imaging. A methodology is presented which determines crystal rotation parameters, i.e. instantaneous rotation axes and angles, from two unindexed Laue diffraction spots. Two-dimensional translation is obtained from dynamic imaging by a single camera. High-speed motion of crystals, including translation and rotation, can be tracked in real time via simultaneous imaging and diffraction.

  1. Dynamic crystal rotation resolved by high-speed synchrotron X-ray Laue diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Huang, J. W.; E, J. C.; Huang, J. Y.; Sun, T.; Fezzaa, K.; Luo, S. N.

    2016-03-30

    Dynamic compression experiments are performed on single-crystal Si under split Hopkinson pressure bar loading, together with simultaneous high-speed (250–350 ns resolution) synchrotron X-ray Laue diffraction and phase-contrast imaging. A methodology is presented which determines crystal rotation parameters,i.e.instantaneous rotation axes and angles, from two unindexed Laue diffraction spots. Two-dimensional translation is obtained from dynamic imaging by a single camera. High-speed motion of crystals, including translation and rotation, can be tracked in real timeviasimultaneous imaging and diffraction.

  2. Imaging outside the box: Resolution enhancement in X-ray coherent diffraction imaging by extrapolation of diffraction patterns

    Energy Technology Data Exchange (ETDEWEB)

    Latychevskaia, Tatiana, E-mail: tatiana@physik.uzh.ch; Fink, Hans-Werner [Physics Institute, University of Zurich, Winterthurerstrasse 190, CH-8057 Zurich (Switzerland); Chushkin, Yuriy; Zontone, Federico [The European Synchrotron Radiation Facility, 71 Avenue des Martyrs, 38000 Grenoble (France)

    2015-11-02

    Coherent diffraction imaging is a high-resolution imaging technique whose potential can be greatly enhanced by applying the extrapolation method presented here. We demonstrate the enhancement in resolution of a non-periodical object reconstructed from an experimental X-ray diffraction record which contains about 10% missing information, including the pixels in the center of the diffraction pattern. A diffraction pattern is extrapolated beyond the detector area and as a result, the object is reconstructed at an enhanced resolution and better agreement with experimental amplitudes is achieved. The optimal parameters for the iterative routine and the limits of the extrapolation procedure are discussed.

  3. Goniometer-based femtosecond X-ray diffraction of mutant 30S ribosomal subunit crystals.

    Science.gov (United States)

    Dao, E Han; Sierra, Raymond G; Laksmono, Hartawan; Lemke, Henrik T; Alonso-Mori, Roberto; Coey, Aaron; Larsen, Kevin; Baxter, Elizabeth L; Cohen, Aina E; Soltis, S Michael; DeMirci, Hasan

    2015-07-01

    In this work, we collected radiation-damage-free data from a set of cryo-cooled crystals for a novel 30S ribosomal subunit mutant using goniometer-based femtosecond crystallography. Crystal quality assessment for these samples was conducted at the X-ray Pump Probe end-station of the Linac Coherent Light Source (LCLS) using recently introduced goniometer-based instrumentation. These 30S subunit crystals were genetically engineered to omit a 26-residue protein, Thx, which is present in the wild-type Thermus thermophilus 30S ribosomal subunit. We are primarily interested in elucidating the contribution of this ribosomal protein to the overall 30S subunit structure. To assess the viability of this study, femtosecond X-ray diffraction patterns from these crystals were recorded at the LCLS during a protein crystal screening beam time. During our data collection, we successfully observed diffraction from these difficult-to-grow 30S ribosomal subunit crystals. Most of our crystals were found to diffract to low resolution, while one crystal diffracted to 3.2 Å resolution. These data suggest the feasibility of pursuing high-resolution data collection as well as the need to improve sample preparation and handling in order to collect a complete radiation-damage-free data set using an X-ray Free Electron Laser.

  4. Goniometer-based femtosecond X-ray diffraction of mutant 30S ribosomal subunit crystals

    Directory of Open Access Journals (Sweden)

    E. Han Dao

    2015-07-01

    Full Text Available In this work, we collected radiation-damage-free data from a set of cryo-cooled crystals for a novel 30S ribosomal subunit mutant using goniometer-based femtosecond crystallography. Crystal quality assessment for these samples was conducted at the X-ray Pump Probe end-station of the Linac Coherent Light Source (LCLS using recently introduced goniometer-based instrumentation. These 30S subunit crystals were genetically engineered to omit a 26-residue protein, Thx, which is present in the wild-type Thermus thermophilus 30S ribosomal subunit. We are primarily interested in elucidating the contribution of this ribosomal protein to the overall 30S subunit structure. To assess the viability of this study, femtosecond X-ray diffraction patterns from these crystals were recorded at the LCLS during a protein crystal screening beam time. During our data collection, we successfully observed diffraction from these difficult-to-grow 30S ribosomal subunit crystals. Most of our crystals were found to diffract to low resolution, while one crystal diffracted to 3.2 Å resolution. These data suggest the feasibility of pursuing high-resolution data collection as well as the need to improve sample preparation and handling in order to collect a complete radiation-damage-free data set using an X-ray Free Electron Laser.

  5. Identification of inversion domains in KTiOPO{sub 4}via resonant X-ray diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Fabrizi, Federica, E-mail: federica.fabrizi@diamond.ac.uk [Diamond Light Source, Harwell Science and Innovation Campus, Didcot, OX11 0DE (United Kingdom); Thomas, Pamela A. [Department of Physics, University of Warwick, Coventry, CV4 7AL (United Kingdom); Nisbet, Gareth; Collins, Stephen P. [Diamond Light Source, Harwell Science and Innovation Campus, Didcot, OX11 0DE (United Kingdom)

    2015-05-14

    The identification and high-resolution mapping of the absolute crystallographic structure in multi-domain ferroelectric KTiOPO{sub 4} is achieved through a novel synchrotron X-ray diffraction method. On a single Bragg reflection, the intensity ratio in resonant diffraction below and above the Ti absorption K edge demonstrates a domain contrast up to a factor of ∼270, thus implementing a non-contact, non-destructive imaging technique with micrometre spatial resolution, applicable to samples of arbitrarily large dimensions. A novel method is presented for the identification of the absolute crystallographic structure in multi-domain polar materials such as ferroelectric KTiOPO{sub 4}. Resonant (or ‘anomalous’) X-ray diffraction spectra collected across the absorption K edge of Ti (4.966 keV) on a single Bragg reflection demonstrate a huge intensity ratio above and below the edge, providing a polar domain contrast of ∼270. This allows one to map the spatial domain distribution in a periodically inverted sample, with a resolution of ∼1 µm achieved with a microfocused beam. This non-contact, non-destructive technique is well suited for samples of large dimensions (in contrast with traditional resonant X-ray methods based on diffraction from Friedel pairs), and its potential is particularly relevant in the context of physical phenomena connected with an absence of inversion symmetry, which require characterization of the underlying absolute atomic structure (such as in the case of magnetoelectric coupling and multiferroics)

  6. Influence of preferred orientation of minerals in the mineralogical identification process by X-ray diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Amanda Luzia da; Oliveira, Arno H. de [Universidade Federal de Minas Gerais (DEN/UFMG), Belo Horizonte, MG (Brazil). Dept. de Engenharia Nuclear; Fernandes, Maria Lourdes Souza, E-mail: lourdesfernandes@ufmg.b [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Inst. de GeoCiencias. Centro de Pesquisa Professor Manoel Teixeira da Costa

    2011-07-01

    The X-ray diffraction corresponds to one of the main techniques for characterization of microstructures in crystalline materials, widely used in the identification of minerals in samples of geological materials. Some minerals have a property called preferred orientation which corresponds to the orientation tendency of the crystals of ground minerals to orient themselves in certain directions according to a preferred crystallographic plane. This property affects the analysis by X-ray diffraction and this fact can generates erroneous results in the characterization. The purpose of this study is to identify the negative influence of the preferred orientation of a mineral in the generation of diffraction patterns obtained in the X-ray diffraction analysis. For this, a sample of muscovite, a mineral of mica group, was prepared by two different methods: the frontal method and the back loading method. In the analysis using the frontal method there was displacement of the XRD pattern in the abscissa axis, where it was observed changes in interplanar distance and angle 2{theta} values, which are essential information for characterization and identification of a mineral. In the analysis using the back loading method, the generated XRD pattern showed no displacement in the axis of abscissas and showed interplanar distance and angle 2{theta} values closer to the real values for the muscovite. The results showed that one can only make improvements to the process of sample preparation minimizing the effect of preferred orientation in the analysis. There is no need to change conditions of diffractometer measurements. (author)

  7. Structural investigation of GaInP nanowires using X-ray diffraction

    DEFF Research Database (Denmark)

    Kriegner, D.; Persson, Johan Mikael; Etzelstorfer, T.

    2013-01-01

    In this work the structure of ternary GaxIn1−xP nanowires is investigated with respect to the chemical composition and homogeneity. The nanowires were grown by metal–organic vapor-phase epitaxy. For the investigation of ensemble fluctuations on several lateral length scales, X-ray diffraction...... gradients along the sample by recording diffraction patterns at different positions. In addition, compositional variations were found also within single nanowires in X-ray energy dispersive spectroscopy measurements....... reciprocal space maps have been analyzed. The data reveal a complicated varying materials composition across the sample and in the nanowires on the order of 20%. The use of modern synchrotron sources, where beam-sizes in the order of several 10μm are available, enables us to investigate compositional...

  8. Crystallization and preliminary X-ray diffraction analysis of maize aldose reductase

    Energy Technology Data Exchange (ETDEWEB)

    Kiyota, Eduardo [Laboratório de Biologia Estrutural, Instituto de Química, Universidade Estadual de Campinas, CP 6154, 13083-970 Campinas-SP (Brazil); Centro de Biologia Molecular e Engenharia Genética, Universidade Estadual de Campinas, Campinas-SP (Brazil); Sousa, Sylvia Morais de [Centro de Biologia Molecular e Engenharia Genética, Universidade Estadual de Campinas, Campinas-SP (Brazil); Santos, Marcelo Leite dos; Costa Lima, Aline da [Laboratório de Biologia Estrutural, Instituto de Química, Universidade Estadual de Campinas, CP 6154, 13083-970 Campinas-SP (Brazil); Menossi, Marcelo [Departamento de Genética e Evolução, Instituto de Biologia, Universidade Estadual de Campinas, Campinas-SP (Brazil); Yunes, José Andrés [Laboratório de Biologia Molecular, Centro Infantil Boldrini, Campinas-SP (Brazil); Aparicio, Ricardo, E-mail: aparicio@iqm.unicamp.br [Laboratório de Biologia Estrutural, Instituto de Química, Universidade Estadual de Campinas, CP 6154, 13083-970 Campinas-SP (Brazil)

    2007-11-01

    Preliminary X-ray diffraction studies of apo maize aldose reductase at 2.0 Å resolution are reported. Maize aldose reductase (AR) is a member of the aldo-keto reductase superfamily. In contrast to human AR, maize AR seems to prefer the conversion of sorbitol into glucose. The apoenzyme was crystallized in space group P2{sub 1}2{sub 1}2{sub 1}, with unit-cell parameters a = 47.2, b = 54.5, c = 100.6 Å and one molecule in the asymmetric unit. Synchrotron X-ray diffraction data were collected and a final resolution limit of 2.0 Å was obtained after data reduction. Phasing was carried out by an automated molecular-replacement procedure and structural refinement is currently in progress. The refined structure is expected to shed light on the functional/enzymatic mechanism and the unusual activities of maize AR.

  9. Electrochemical cell for in situ x-ray diffraction under ultrapure conditions

    DEFF Research Database (Denmark)

    Koop, T.; Schindler, W.; Kazimirov, A.

    1998-01-01

    of the crystal using a Luggin capillary and a standard reference electrode. We demonstrate the performance of our cell by in situ synchrotron x-ray diffraction measurements on ultrathin Co layers electrodeposited on Cu(001) in an aqueous H(2)SO(4)/CoSO(4) solution. (C) 1998 American Institute of Physics.......An electrochemical cell has been developed for in situ x-ray diffraction from a working electrode under clean conditions equivalent to ultrahigh vacuum conditions of 5 x 10(-10) mbar. The substrate crystals can be prepared ex situ and transferred into the cell under protection of ultrapure water...... within a few seconds. The oxygen level in the electrolyte is reduced by continuous N(2) flow to less than 0.2% compared to that of a fresh electrolyte. This can be done while rotating the cell by 360 degrees about the surface normal. The electrode potential is accurately measured at the position...

  10. Synchrotron radiation X-ray powder diffraction techniques applied in hydrogen storage materials - A review

    Directory of Open Access Journals (Sweden)

    Honghui Cheng

    2017-02-01

    Full Text Available Synchrotron radiation is an advanced collimated light source with high intensity. It has particular advantages in structural characterization of materials on the atomic or molecular scale. Synchrotron radiation X-ray powder diffraction (SR-XRPD has been successfully exploited to various areas of hydrogen storage materials. In the paper, we will give a brief introduction on hydrogen storage materials, X-ray powder diffraction (XRPD, and synchrotron radiation light source. The applications of ex situ and in situ time-resolved SR-XRPD in hydrogen storage materials, are reviewed in detail. Future trends and proposals in the applications of the advanced XRPD techniques in hydrogen storage materials are also discussed.

  11. Crystallographic Characterization of Extraterrestrial Materials by Energy-Scanning X-ray Diffraction

    Science.gov (United States)

    Hagiya, Kenji; Mikouchi, Takashi; Ohsumi, Kazumasa; Terada, Yasuko; Yagi, Naoto; Komatsu, Mutsumi; Yamaguchi, Shoki; Hirata, Arashi; Kurokawa, Ayaka; Zolensky, Michael E. (Principal Investigator)

    2016-01-01

    We have continued our long-term project using X-ray diffraction to characterize a wide range of extraterrestrial samples. The stationary sample method with polychromatic X-rays is advantageous because the irradiated area of the sample is always same and fixed, meaning that all diffraction spots occur from the same area of the sample, however, unit cell parameters cannot be directly obtained by this method though they are very important for identification of mineral and for determination of crystal structures. In order to obtain the cell parameters even in the case of the sample stationary method, we apply energy scanning of a micro-beam of monochromatic SR at SPring-8.

  12. A secondary graphite crystal spectrometer for anomalous X-ray diffraction experiments

    CERN Document Server

    Stachs, O; Himmel, B; Gerber, T

    1999-01-01

    A new design for implementation of anomalous X-ray diffraction experiments is proposed. The exploitation of a graphite crystal spectrometer with good energy resolution in combination with an acceptable counting rate opens new possibilities to carry out AWAXS experiments and calculate partial structure functions. The proof of this measurement principle is demonstrated by presentation of the partial structure factor and radial distribution function for rubidium germanate glasses around the germanium component. (author)

  13. Polymorphism in B-DNA: X-ray diffraction studies on Li-DNA fibres

    Indian Academy of Sciences (India)

    tribpo

    Abstract. From X-ray diffraction studies it is generally believed that B-DNA has the structural parameters n = 10 and h = 3·4 Å. However, for the first time we report that polymorphism in the B-form can be observed in DNA fibres. This was achieved by the precise control of salt and humidity in fibres and by the application of the ...

  14. Simulations of Time-Resolved X-Ray Diffraction in Laue Geometry

    OpenAIRE

    Lings, B.; DeCamp, M. F.; Reis, D.A.; Fahy, S.; Wark, J. S.

    2005-01-01

    A method of computer simulation of Time-Resolved X-ray Diffraction (TRXD) in asymmetric Laue (transmission) geometry with an arbitrary propagating strain perpendicular to the crystal surface is presented. We present two case studies for possible strain generation by short-pulse laser irradiation: (i) a thermoelastic-like analytic model; (ii) a numerical model including effects of electron-hole diffusion, Auger recombination, deformation potential and thermal diffusion. A comparison with recen...

  15. X-ray diffraction peak profiles from threading dislocations in GaN epitaxial films

    OpenAIRE

    Kaganer, V M; Brandt, O.; Trampert, A.; Ploog, K. H.

    2004-01-01

    We analyze the lineshape of x-ray diffraction profiles of GaN epitaxial layers with large densities of randomly distributed threading dislocations. The peaks are Gaussian only in the central, most intense part of the peak, while the tails obey a power law. The $q^{-3}$ decay typical for random dislocations is observed in double-crystal rocking curves. The entire profile is well fitted by a restricted random dislocation distribution. The densities of both edge and screw threading dislocations ...

  16. Measurement and Interpretation of Diffuse Scattering in X-Ray Diffraction for Macromolecular Crystallography

    Energy Technology Data Exchange (ETDEWEB)

    Wall, Michael E. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-10-16

    X-ray diffraction from macromolecular crystals includes both sharply peaked Bragg reflections and diffuse intensity between the peaks. The information in Bragg scattering reflects the mean electron density in the unit cells of the crystal. The diffuse scattering arises from correlations in the variations of electron density that may occur from one unit cell to another, and therefore contains information about collective motions in proteins.

  17. Analysis of diatomite sediments from a paleolake in central Mexico using PIXE, X-ray tomography and X-ray diffraction

    Science.gov (United States)

    Miranda, J.; Oliver, A.; Vilaclara, G.; Rico-Montiel, R.; Macías, V. M.; Ruvalcaba, J. L.; Zenteno, M. A.

    1994-03-01

    Diatomite samples from paleolake Tlaxcala, in Central Mexico, have been analyzed using proton induced X-ray emission (PIXE), X-ray tomography and X-ray diffraction. Chiseled blocks were scanned with a 0.7 MeV proton beam, 0.1 mm in diameter, in 0.25 mm steps across the sediments. X-ray tomography with the same step sizes was then applied, in order to compare the concentrations obtained with PIXE and the material density in the sediment layers. Three different kinds of layers were found, related to their colors: dark, white and gray. The composition of the layers is fairly uniform. The dark zone is enriched in Al, K, Ca, Ti, Mn, and Fe. This dark layer may be associated with eruptions of the Malitzin volcano. The white zone is found to contain diatomite of a high purity, with traces of K, Ca, and Fe, while the gray zones are also Al enriched, suggesting a clay contamination of the diatomite. X-ray diffraction of materials obtained from each main layer showed that the white and gray phases are highly amorphous, with a small component of cristobalite, as expected from the diatom sediment diagenesis, while the dark layer contains also important amounts of anorthite and orthoclase, supporting the volcanic origin of this layer.

  18. Time-resolved x-ray diffraction techniques for bulk polycrystalline materials under dynamic loading

    Energy Technology Data Exchange (ETDEWEB)

    Lambert, P. K.; Hustedt, C. J.; Zhao, M.; Ananiadis, A. G.; Hufnagel, T. C. [Department of Materials Science and Engineering, Johns Hopkins University, Baltimore, Maryland 21218 (United States); Vecchio, K. S. [Department of NanoEngineering, University of California San Diego, La Jolla, California 92093 (United States); Huskins, E. L. [Oak Ridge Institute for Science and Education, Oak Ridge, Tennessee 37830 (United States); US Army Research Laboratory, Aberdeen Proving Ground, Aberdeen, Maryland 21005 (United States); Casem, D. T. [US Army Research Laboratory, Aberdeen Proving Ground, Aberdeen, Maryland 21005 (United States); Gruner, S. M. [Department of Physics, Cornell University, Ithaca, New York 14853 (United States); Cornell High Energy Synchrotron Source (CHESS), Cornell University, Ithaca, New York 14853 (United States); Kavli Institute at Cornell for Nanoscale Science, Cornell University, Ithaca, New York 14853 (United States); Tate, M. W.; Philipp, H. T.; Purohit, P.; Weiss, J. T. [Department of Physics, Cornell University, Ithaca, New York 14853 (United States); Woll, A. R. [Cornell High Energy Synchrotron Source (CHESS), Cornell University, Ithaca, New York 14853 (United States); Kannan, V.; Ramesh, K. T. [Department of Mechanical Engineering, Johns Hopkins University, Baltimore, Maryland 21218 (United States); Kenesei, P.; Okasinski, J. S.; Almer, J. [X-ray Science Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States)

    2014-09-15

    We have developed two techniques for time-resolved x-ray diffraction from bulk polycrystalline materials during dynamic loading. In the first technique, we synchronize a fast detector with loading of samples at strain rates of ∼10{sup 3}–10{sup 4} s{sup −1} in a compression Kolsky bar (split Hopkinson pressure bar) apparatus to obtain in situ diffraction patterns with exposures as short as 70 ns. This approach employs moderate x-ray energies (10–20 keV) and is well suited to weakly absorbing materials such as magnesium alloys. The second technique is useful for more strongly absorbing materials, and uses high-energy x-rays (86 keV) and a fast shutter synchronized with the Kolsky bar to produce short (∼40 μs) pulses timed with the arrival of the strain pulse at the specimen, recording the diffraction pattern on a large-format amorphous silicon detector. For both techniques we present sample data demonstrating the ability of these techniques to characterize elastic strains and polycrystalline texture as a function of time during high-rate deformation.

  19. Residual stress characterization of welds and post-weld processes using x-ray diffraction techniques

    Science.gov (United States)

    Brauss, Michael E.; Pineault, James A.; Eckersley, John S.

    1998-03-01

    This paper illustrates the importance of residual stress characterization in welds and post weld processes. The failure to characterize residual stresses created during welding and/or post weld processes can lead to unexpected occurrences of stress corrosion cracking, distortion, fatigue cracking as well as instances of over design or over processing. The development of automated residual stress mapping and the availability of portable and fast equipment have now made the characterization of residual stresses using x-ray diffraction practical for process control and optimization. The paper presents examples where x-ray diffraction residual stress characterization techniques were applied on various kinds of welds including arc welds, TIG welds, resistance welds, laser welds and electron beam welds. The nondestructive nature of the x-ray diffraction technique has made the residual stress characterization of welds a useful tool for process optimization and failure analysis, particularly since components can be measured before and after welding and post welding processes. Some examples presented show the residual stresses before and after the application of post weld processes such as shot peening, grinding and heat treatment.

  20. AUSPEX: a graphical tool for X-ray diffraction data analysis.

    Science.gov (United States)

    Thorn, Andrea; Parkhurst, James; Emsley, Paul; Nicholls, Robert A; Vollmar, Melanie; Evans, Gwyndaf; Murshudov, Garib N

    2017-09-01

    In this paper, AUSPEX, a new software tool for experimental X-ray data analysis, is presented. Exploring the behaviour of diffraction intensities and the associated estimated uncertainties facilitates the discovery of underlying problems and can help users to improve their data acquisition and processing in order to obtain better structural models. The program enables users to inspect the distribution of observed intensities (or amplitudes) against resolution as well as the associated estimated uncertainties (sigmas). It is demonstrated how AUSPEX can be used to visually and automatically detect ice-ring artefacts in integrated X-ray diffraction data. Such artefacts can hamper structure determination, but may be difficult to identify from the raw diffraction images produced by modern pixel detectors. The analysis suggests that a significant portion of the data sets deposited in the PDB contain ice-ring artefacts. Furthermore, it is demonstrated how other problems in experimental X-ray data caused, for example, by scaling and data-conversion procedures can be detected by AUSPEX.

  1. X-Ray diffraction observation of surface damage in chemical-mechanical polished gallium arsenide

    Science.gov (United States)

    Wang, V. S.; Matyi, R. J.

    1992-01-01

    Two novel x-ray diffraction techniques with enhanced surface sensitivity, grazing incidence x-ray diffraction (GIXD) and inclined Bragg plane x-ray diffraction (IBXD), have been used to study surface damage in gallium arsenide (GaAs) due to bromine/methanol (Br2/MeOH) chemical mechanical (CM) polishing. A factorial design was implemented to determine the effects of four polishing variables on the surface structure of GaAs. Precise lattice parameter measurements were made in both the surface regions using GIXD and deeper into subsurface regions using IBXD after the various CM polishing treatments. Bromine concentration was found to primarily affect the surface lattice parameter, while the total polish time influenced both the surface and subsurface lattice parameters in GaAs samples that were heavily damaged prior to CM polishing. The combined effect of polishing pad rotation speed and the force exerted on the sample was found to have a much greater effect on the surface lattice parameter than either variable had alone.

  2. Quantitative energy-dispersive x-ray diffraction for identification of counterfeit medicines: a preliminary study

    Science.gov (United States)

    Crews, Chiaki C. E.; O'Flynn, Daniel; Sidebottom, Aiden; Speller, Robert D.

    2015-06-01

    The prevalence of counterfeit and substandard medicines has been growing rapidly over the past decade, and fast, nondestructive techniques for their detection are urgently needed to counter this trend. In this study, energy-dispersive X-ray diffraction (EDXRD) combined with chemometrics was assessed for its effectiveness in quantitative analysis of compressed powder mixtures. Although EDXRD produces lower-resolution diffraction patterns than angular-dispersive X-ray diffraction (ADXRD), it is of interest for this application as it carries the advantage of allowing the analysis of tablets within their packaging, due to the higher energy X-rays used. A series of caffeine, paracetamol and microcrystalline cellulose mixtures were prepared with compositions between 0 - 100 weight% in 20 weight% steps (22 samples in total, including a centroid mixture), and were pressed into tablets. EDXRD spectra were collected in triplicate, and a principal component analysis (PCA) separated these into their correct positions in the ternary mixture design. A partial least-squares (PLS) regression model calibrated using this training set was validated using both segmented cross-validation, and with a test set of six samples (mixtures in 8:1:1 and 5⅓:2⅓:2⅓ ratios) - the latter giving a root-mean square error of prediction (RMSEP) of 1.30, 2.25 and 2.03 weight% for caffeine, paracetamol and cellulose respectively. These initial results are promising, with RMSEP values on a par with those reported in the ADXRD literature.

  3. Structure Refinement of (Sr,BaNb2O6 Ceramic Powder from Neutron and X-Rays Diffraction Data

    Directory of Open Access Journals (Sweden)

    J.G. Carrio

    2002-03-01

    Full Text Available The structure of polycrystalline strontium barium niobate at room temperature was refined by the Rietveld method. Sintered ceramic samples were used to collect powder neutron and X-ray diffraction data. The ratio Sr/Ba ~ 64/36 was found from the initial batch composition Sr0.61Ba0.39Nb2O6, corroborating with the quantitative X-ray dispersive spectroscopy (EDS measurements. The structure is tetragonal with cell parameters a, b = 12.4504(3 Å and c = 3.9325(1 Å and space group P4bm. It was not necessary to introduce any positional disorder for the oxygen atoms. Cation Nb+5 displacements not parallel to the c direction are presented, which can influence the behavior of the ferroelectric properties.

  4. Computer simulation tools for X-ray analysis scattering and diffraction methods

    CERN Document Server

    Morelhão, Sérgio Luiz

    2016-01-01

    The main goal of this book is to break down the huge barrier of difficulties faced by beginners from many fields (Engineering, Physics, Chemistry, Biology, Medicine, Material Science, etc.) in using X-rays as an analytical tool in their research. Besides fundamental concepts, MatLab routines are provided, showing how to test and implement the concepts. The major difficult in analyzing materials by X-ray techniques is that it strongly depends on simulation software. This book teaches the users on how to construct a library of routines to simulate scattering and diffraction by almost any kind of samples. It provides to a young student the knowledge that would take more than 20 years to acquire by working on X-rays and relying on the available textbooks. In this book, fundamental concepts in applied X-ray physics are demonstrated through available computer simulation tools. Using MatLab, more than eighty routines are developed for solving the proposed exercises, most of which can be directly used in experimental...

  5. [X-ray diffraction and infrared spectrum analysis of fault gouge in Wenchuan seismic belt].

    Science.gov (United States)

    Wang, Zheng-Yang; Cao, Jian-Jin; Luo, Song-Ying; Liao, Yi-Peng

    2014-05-01

    Wenchuan earthquake produced a series of co-seismic surface ruptures in Leigu and Zhaojiagou, and we collected samples of co-seismic fault gouge in the surface ruptures as well as the old gouge in the fault of Nanba. Testing The new and old fault gouge was tested with X-ray diffraction and infrared absorption spectra, and its characteristics such as mineral compositions, clay mineral contents and combinations were comprehensively analyzed. The results display obvious differences between the new and old fault gouge, showing that the old fault gouge is mainly composed of wall rock debris or milled powders, while the main components of new fault gouge are clay minerals. The assemblage of clay minerals composition shows that the environment of the fault activity was mainly warm and humid, and the clay minerals were mainly transformed by low temperature and low pressure dynamic metamorphism. And this also partly indicates that the latest way of the fault activity in this area may be a creeping. However the previous researches on the fault gouge of Wenchuan earthquake fault zone are mainly focused on its mechanical properties as well as its texture and structure, the research in this paper is to determine the physical and chemical environment of fault activity through the mineral compositions and clay mineral contents in the fault gouge characteristics, and this research has important scientific significance to the researches on the evolution of the fault environment and the activity mechanism of the earthquake.

  6. Electrochemistry and in-situ x-ray diffraction of InSb in lithium batteries.

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, C. S.; Vaughey, J. T.; Thackeray, M. M.; Sarakonsri, T.; Hackney, S. A.; Fransson, L.; Edstrom, K.; Thomas, J. O.; Chemical Engineering

    2000-08-01

    The electrochemical reactions of lithium with the intermetallic compound, InSb, were studied in lithium coin cells using laminate electrodes fabricated from either single-crystal InSb wafers or ball-milled samples. In-situ X-ray diffraction data show that the InSb zinc-blende framework is unstable to extensive reaction with lithium; In is extruded from a fixed Sb lattice during 'discharge' and is partially incorporated back into the lattice during 'charge'. Despite the loss of some In from the structure, the indium antimonide electrode provides capacities in excess of 300 mAh/g with excellent reversibility. Cyclic voltammetry was used to study the electrochemical processes in greater detail. Lithiated indium products are formed below {approx}600 mV versus Li. The electrode can be discharged at high rates, delivering 150 mAh/g at 3.6 mA/cm{sub 2} between 1.2 and 0.2 V versus Li. These data hold exciting prospects for the development of intermetallic insertion electrodes for practical room-temperature Li-ion cells.

  7. Spectroscopic and X-ray Diffraction Study of Structural Disorder in Cryomilled and Amorphous Griseofulvin

    Energy Technology Data Exchange (ETDEWEB)

    A Zarow; B Zhou; X Wang; R Pinal; Z Iqbal

    2011-12-31

    Structural disorder induced by cryogenic milling and by heating to the amorphous phase in the active pharmaceutical ingredient Griseofulvin has been studied using Raman spectroscopy, X-ray powder diffraction (XRPD), and fluorescence spectroscopy. A broad, exciting-frequency-independent scattering background in the Raman spectra and changes in intensities and splitting of some of the Raman lines due to lattice and molecular modes have been observed. In the cryomilled samples this strong background is deconvoluted into two components: one due to lattice disorder induced by cryomilling and the other due to Mie scattering from nanosized crystallites. A single-component background scattering attributed to lattice disorder is seen in the Raman spectrum of the amorphous sample. Fluorescence measurements showed an intrinsic fluorescence signal in as-received Griseofulvin that does not correspond to the inelastic background in the Raman spectra and, moreover, decreases in intensity upon cryomilling, thus excluding an assignment of the Raman background intensity to impurity- or molecular-defect-induced fluorescence. Wide-angle XRPD measurements on cryomilled Griseofulvin shows a broad two-component background consistent with the background-scattering component in the Raman data associated with lattice disorder, but at longer correlation lengths. Persistence of this disorder to even longer lengths is evident in small-angle synchrotron XRPD data on micronized Griseofulvin taken as a function of temperature from the crystalline to the amorphous phase.

  8. A high pressure cell for simultaneous osmotic pressure and x-ray diffraction measurements

    Science.gov (United States)

    Gauthé, Béatrice L. L. E.; Heron, Andrew J.; Seddon, John M.; Ces, Oscar; Templer, Richard H.

    2009-03-01

    In this paper, we report on a novel osmotic cell, developed to simultaneously subject a sample to osmotic stress and measure structural changes by small angle x-ray diffraction. The osmotic cell offers many advantages over more conventional methods of osmotically stressing soft materials to measure their structural response. In particular, a full osmotic analysis can be performed with a single small sample (25 μl). This reduces sample handling and the associated systematic errors, as well as enabling tight control and monitoring of the thermodynamic environment during osmosis, thereby increasing measurement precision. The cell design enables control of osmotic pressure to ±0.04 bar over a pressure range of 1-100 bar, and temperature control to ±0.05 °C. Under these conditions, the lattice spacing in lyotropic structures was resolved to better than ±0.005 Å. Using the osmotic cell, we demonstrate good agreement with previous conventional measurements on the energy of dehydrating the fluid lamellar phase of dioleoylphosphatidylcholine in water.

  9. X-Ray diffraction study of KTiOPO{sub 4} single crystals doped with hafnium

    Energy Technology Data Exchange (ETDEWEB)

    Novikova, N. E., E-mail: natnov@ns.crys.ras.ru; Verin, I. A.; Sorokina, N. I.; Alekseeva, O. A. [Russian Academy of Sciences, Shubnikov Institute of Crystallography (Russian Federation); Orlova, E. I.; Voronkova, V. I. [Moscow State University, Faculty of Physics (Russian Federation)

    2011-05-15

    Single crystals of KTi{sub 1-x}Hf{sub x}OPO{sub 4} (x = 0.015(2), 0.035(1), and 0.128(1) are reinvestigated by precision X-ray diffraction at room temperature. It is found that the implantation of hafnium atoms in the crystal structure of KTiOPO{sub 4} does not lead to significant changes in the framework and affects only the positions of the potassium atoms in the channel. Our studies reveal the displacements of the potassium atoms from their main and additional positions in the structure of pure KTP in all three structures studied. The largest displacements from the K1 Prime and K1 Double-Prime additional positions are observed in the structure with x = 0.035. At this hafnium concentration, the occupancy of the main positions of potassium atoms decreases and the occupancy of the additional positions increases in relation to those in KTP. This redistribution of potassium atoms enhances the nonuniformity of distribution of the electron density in the vicinity of their positions, which is probably responsible for the increase in the nonlinear susceptibility of KTP crystals that contain 3.5% hafnium in relation to crystals of pure KTP.

  10. Multiple-wave diffraction in high energy resolution back-reflecting x-ray optics.

    Science.gov (United States)

    Stetsko, Yuri P; Keister, J W; Coburn, D S; Kodituwakku, C N; Cunsolo, A; Cai, Y Q

    2011-10-07

    We have studied the effects of multiple-wave diffraction in a novel optical scheme recently published by Shvyd'ko et al. utilizing Bragg diffraction of x rays in backscattering geometry from asymmetrically cut crystals for achieving energy resolutions beyond the intrinsic width of the Bragg reflection. By numerical simulations based on dynamic x-ray diffraction and by experimentation involving two-dimensional angular scans of the back-reflecting crystal, multiple-wave diffraction was found to contribute up to several tens percent loss of efficiency but can be avoided without degrading the energy resolution of the original scheme by careful choice of azimuthal orientation of the diffracting crystal surface and by tilting of the crystal perpendicular to the dispersion plane.

  11. Imaging outside the box: Resolution enhancement in X-ray coherent diffraction imaging by extrapolation of diffraction patterns

    CERN Document Server

    Latychevskaia, Tatiana; Zontone, Federico; Fink, Hans-Werner

    2015-01-01

    We demonstrate enhancement in resolution of a noncrystalline object reconstructed from an experimental X-ray diffraction pattern by extrapolating the measured diffraction intensities beyond the detector area. The experimental record contains about 10% missing information, including the pixels in the center of the diffraction pattern. The extrapolation is done by applying an iterative routine. The optimal parameters for implementing the iterative routine, including initial padding distribution and an object support, are studied. Extrapolation results in resolution enhancement and better matching between the recovered and experimental amplitudes in the Fourier domain. The limits of the extrapolation procedure are discussed.

  12. In situ X-ray ptychography imaging of high-temperature CO2 acceptor particle agglomerates

    DEFF Research Database (Denmark)

    Høydalsvik, Kristin; Fløystad, Jostein Bø; Zhao, Tiejun

    2014-01-01

    Imaging nanoparticles under relevant reaction conditions of high temperature and gas pressure is difficult because conventional imaging techniques, like transmission electron microscopy, cannot be used. Here we demonstrate that the coherent diffractive imaging technique of X-ray ptychography can...... be used for in situ phase contrast imaging in structure studies at atmospheric pressure and elevated temperatures. Lithium zirconate, a candidate CO2 capture material, was studied at a pressure of one atmosphere in air and in CO2, at temperatures exceeding 600 °C. Images with a spatial resolution better...

  13. Crystallization and preliminary X-ray diffraction studies of ferredoxin reductase from Leptospira interrogans

    Energy Technology Data Exchange (ETDEWEB)

    Nascimento, Alessandro S.; Ferrarezi, Thiago [Instituto de Física de São Carlos, Universidade de São Paulo, Av. Trabalhador Saocarlense 400, São Carlos, SP, 13560-970 (Brazil); Catalano-Dupuy, Daniela L.; Ceccarelli, Eduardo A. [Facultad de Ciencias Bioquímicas y Farmacéuticas, Molecular Biology Division, Instituto de Biología Molecular y Celular de Rosario (IBR), CONICET, Universidad Nacional de Rosario, Suipacha 531, S2002LRK Rosario (Argentina); Polikarpov, Igor, E-mail: ipolikarpov@if.sc.usp.br [Instituto de Física de São Carlos, Universidade de São Paulo, Av. Trabalhador Saocarlense 400, São Carlos, SP, 13560-970 (Brazil)

    2006-07-01

    Crystals adequate for X-ray diffraction analysis have been prepared from L. interrogans ferredoxin-NADP{sup +} reductase. Ferredoxin-NADP{sup +} reductase (FNR) is an FAD-containing enzyme that catalyzes electron transfer between NADP(H) and ferredoxin. Here, results are reported of the recombinant expression, purification and crystallization of FNR from Leptospira interrogans, a parasitic bacterium of animals and humans. The L. interrogans FNR crystals belong to a primitive monoclinic space group and diffract to 2.4 Å resolution at a synchrotron source.

  14. Diffraction of short X-ray pulses in the general asymmetric Laue case - an analytic treatment.

    Science.gov (United States)

    Malgrange, C; Graeff, W

    2003-05-01

    After briefly describing the concept of short X-ray pulses (delta-function), the diffraction of such a short pulse by a crystal in the asymmetric Laue case is given. The results of the dynamical theory are adopted and an analytic result for the intensity distribution behind the crystal in the diffracted direction as well as in the forward direction is given and discussed in detail. The incoming delta pulse is no longer infinitely short but shows a pronounced structure over a limited temporal or spatial region which is connected to the well known Pendellösung effect. Also the limitations of these findings are critically inspected.

  15. X-ray third-order nonlinear dynamical diffraction in a crystal

    Energy Technology Data Exchange (ETDEWEB)

    Balyan, M. K., E-mail: mbalyan@ysu.am [Yerevan State University, Faculty of Physics (Armenia)

    2015-12-15

    The dynamic diffraction of an X-ray wave in a crystal with a third-order nonlinear response to external field strength has been theoretically investigated. General equations for the wave propagation in crystal and nonlinear Takagi equations for both ideal and deformed crystals are derived. Integrals of motion are determined for the nonlinear problem of dynamic diffraction. The results of the numerical calculations of reflectivity in the symmetric Laue geometry for an incident plane wave and the intensity distributions on the output crystal surface for a point source are reported as an example.

  16. Hard X-ray nanoimaging method using local diffraction from metal wire

    Energy Technology Data Exchange (ETDEWEB)

    Takano, Hidekazu, E-mail: htakano@sci.u-hyogo.ac.jp; Konishi, Shigeki; Shimomura, Sho; Azuma, Hiroaki; Tsusaka, Yoshiyuki; Kagoshima, Yasushi [Center for Novel Material Science under Multi-Extreme Conditions, Graduate School of Material Science, University of Hyogo, Kamigori, Hyogo 678-1297 (Japan)

    2014-01-13

    A simple hard X-ray imaging method achieving a high spatial resolution is proposed. Images are obtained by scanning a metal wire through the wave field to be measured and rotating the sample to collect data for back projection calculations; the local diffraction occurring at the edges of the metal wire operates as a narrow line probe. In-line holograms of a test sample were obtained with a spatial resolution of better than 100 nm. The potential high spatial resolution of this method is shown by calculations using diffraction theory.

  17. High temperature x-ray micro-tomography

    Energy Technology Data Exchange (ETDEWEB)

    MacDowell, Alastair A., E-mail: aamacdowell@lbl.gov; Barnard, Harold; Parkinson, Dilworth Y.; Gludovatz, Bernd [Lawrence Berkeley National Lab., Berkeley, CA 94720 (United States); Haboub, Abdel [Lawrence Berkeley National Lab., Berkeley, CA 94720 (United States); current –Lincoln Univ., Jefferson City, Missouri, 65101 (United States); Larson, Natalie; Zok, Frank [University California Santa Barbara, Santa Barbara CA 93106 (United States); Panerai, Francesco; Mansour, Nagi N. [NASA Ames Research Centre, Moffett Field, CA, 94035 (United States); Bale, Hrishikesh [University California Berkeley, Berkeley, CA 94720 (United States); current - Carl Zeiss X-ray Microscopy, 4385 Hopyard Rd #100, Pleasanton, CA 94588 (United States); Acevedo, Claire [Lawrence Berkeley National Lab., Berkeley, CA 94720 (United States); University California San Francisco, San Francisco, CA 94143 (United States); Liu, Dong [University of Bristol, Bristol BS8 1TH (United Kingdom); Ritchie, Robert O. [Lawrence Berkeley National Lab., Berkeley, CA 94720 (United States); University California Berkeley, Berkeley, CA 94720 (United States)

    2016-07-27

    There is increasing demand for 3D micro-scale time-resolved imaging of samples in realistic - and in many cases extreme environments. The data is used to understand material response, validate and refine computational models which, in turn, can be used to reduce development time for new materials and processes. Here we present the results of high temperature experiments carried out at the x-ray micro-tomography beamline 8.3.2 at the Advanced Light Source. The themes involve material failure and processing at temperatures up to 1750°C. The experimental configurations required to achieve the requisite conditions for imaging are described, with examples of ceramic matrix composites, spacecraft ablative heat shields and nuclear reactor core Gilsocarbon graphite.

  18. A study of X-ray multiple diffraction by means of section topography.

    Science.gov (United States)

    Kohn, V G; Smirnova, I A

    2015-09-01

    The results of theoretical and experimental study are presented for the question of how the X-ray multiple diffraction in a silicon single crystal influences the interference fringes of section topography for the 400 reflection in the Laue case. Two different cases of multiple diffraction are discovered for zero and very small values of the azimuthal angle for the sample in the form of a plate with the surface normal to the 001 direction. The cases are seen on the same topogram without rotation of the crystal. Accurate computer simulations of the section topogram for the case of X-ray multiple diffraction are performed for the first time. It is shown that the structure of interference fringes on the section topogram in the region of multiple diffraction becomes more complicated. It has a very sharp dependence on the azimuthal angle. The experiment is carried out using a laboratory source under conditions of low resolution over the azimuthal angle. Nevertheless, the characteristic inclination of the interference fringes on the tails of the multiple diffraction region is easily seen. This phenomenon corresponds completely to the computer simulations.

  19. In situ X-ray diffraction studies on the piezoelectric response of PZT thin films

    Energy Technology Data Exchange (ETDEWEB)

    Davydok, A., E-mail: davydok@mpie.de [Aix Marseille Université, CNRS, Université de Toulon, IM2NP UMR 7334, 13397 Marseille (France); Max-Planck-Institut für Eisenforschung, Department Structure and Nano-/Micromechanics of Materials, D-40237 Düsseldorf (Germany); Cornelius, T.W. [Aix Marseille Université, CNRS, Université de Toulon, IM2NP UMR 7334, 13397 Marseille (France); Mocuta, C. [SOLEIL Synchrotron, DiffAbs beamline, L' Orme des Merisiers, Saint-Aubin - BP 48, 91192 Gif-sur-Yvette Cedex (France); Lima, E.C. [Universidade Federal do Tocantins, 77500-000 Porto Nacional, TO (Brazil); Araujo, E.B. [Departamento de Fisica e Quimica, Universidade Estadual Paulista, Av. Brasil, 56 Centro, 15385-000 Ilha Solteira, SP (Brazil); Thomas, O. [Aix Marseille Université, CNRS, Université de Toulon, IM2NP UMR 7334, 13397 Marseille (France)

    2016-03-31

    Piezoelectric properties of randomly oriented self-polarized PbZr{sub 0.50}Ti{sub 0.50}O{sub 3} (PZT) thin films were investigated using in situ synchrotron X-ray diffraction. Possibilities for investigating the piezoelectric effect using micro-sized hard X-ray beams are demonstrated and perspectives for future dynamical measurements on PZT samples with variety of compositions and thicknesses are given. Studies performed on the crystalline [100, 110] directions evidenced piezoelectric anisotropy. The piezoelectric coefficient d{sub 33} was calculated in terms of the lab reference frame (d{sub perp}) and found to be two times larger along the [100] direction than along the [110] direction. The absolute values for the d{sub perp} amount to 120 and 230 pm/V being in good agreement with experimental and theoretical values found in literature for bulk PZT ceramics. - Highlights: • We performed in situ synchrotron X-ray diffraction studies on (PZT) thin films. • We discuss anisotropy of piezo effect in different crystallographic directions. • Perpendicular component Piezo coefficient of thin PZT layer is defined.

  20. Mineral identification in Colombian coals using Moessbauer spectroscopy and X-ray diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Fajardo, M. [Universidad del Valle, A.A, Departamento de Fisica (Colombia); Mojica, J. [Instituto Nacional de Investigaciones en Geociencia, Mineria y Quimica (INGEOMINAS) (Colombia); Barraza, J. [Universidad del Valle, A.A, Departamento de Procesos Quimicos, Facultad de Ingenieria (Colombia); Perez Alcazar, G.A.; Tabares, J.A. [Universidad del Valle, A.A, Departamento de Fisica (Colombia)

    1999-11-15

    Minerals were identified in three Colombian coal samples from the Southwest of the country using Moessbauer spectroscopy and X-ray diffraction. Original and sink separated coal fractions of specific gravity 1.40 and 1.60 with particle size less than 600 {mu}m were used in the study. Using Moessbauer spectroscopy, the minerals identified in the original coal samples were pyrite jarosite, ankerite, illite and ferrous sulfate, whereas by means of X-ray diffraction, minerals identified were kaolinite, quartz, pyrite, and jarosite. Differences in mineral composition were found in the original and sink separated fractions using both techniques. Moessbauer spectra show that the mineral phases in low concentrations such as illite, ankerite and ferrous sulfate do not always appear in the spectra of sink coals, despite of those minerals occurring in the original coal, due to the fact that they are associated with the organic matter and not liberated in the grinding process. X-ray results show that the peak intensity grows as the specific gravity is increased indicating that the density separation method could be an effective process to clean coal.

  1. Investigation of electronic order using resonant soft X-ray diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Schlappa, J.

    2006-12-01

    The aim of this PhD work was the application of resonant soft X-ray diffraction technique for the investigation of electronic order in transition metal oxides at the TM L{sub 2,3}-edge, trying to obtain a quantitative understanding of the data. The method was first systematically explored through application to a model system in order to test the feasibility of the technique and to understand of how X-ray optical effects have to be taken into account. Two more complex systems were investigated; stripe order in La{sub 1.8}Sr{sub 0.2}NiO{sub 4} and charge and orbital order in Fe{sub 3}O{sub 4}. The main focus of the work was on the spectroscopic potential of the technique, trying to obtain a level of quantitative description of the data. For X-ray absorption spectroscopy (XAS) from transition metal oxides, cluster configuration interaction calculation provides a powerful and realistic microscopic theory. In the frame work of this thesis cluster theory, considering explicit hybridization effects between the TM-ion and the surrounding oxygen ligands, has been applied for the first time to describe resonant diffraction data. (orig.)

  2. Performance calculations of the X-ray powder diffraction beamline at NSLS-II.

    Science.gov (United States)

    Shi, Xianbo; Ghose, Sanjit; Dooryhee, Eric

    2013-03-01

    The X-ray Powder Diffraction (XPD) beamline at the National Synchrotron Light Source II is a multi-purpose high-energy X-ray diffraction beamline with high throughput and high resolution. The beamline uses a sagittally bent double-Laue crystal monochromator to provide X-rays over a large energy range (30-70 keV). In this paper the optical design and the calculated performance of the XPD beamline are presented. The damping wiggler source is simulated by the SRW code and a filter system is designed to optimize the photon flux as well as to reduce the heat load on the first optics. The final beamline performance under two operation modes is simulated using the SHADOW program. For the first time a multi-lamellar model is introduced and implemented in the ray tracing of the bent Laue crystal monochromator. The optimization and the optical properties of the vertical focusing mirror are also discussed. Finally, the instrumental resolution function of the XPD beamline is described in an analytical method.

  3. Microelemental and mineral compositions of pathogenic biomineral concrements: SRXFA, X-ray powder diffraction and vibrational spectroscopy data

    Energy Technology Data Exchange (ETDEWEB)

    Moroz, T.N. [Institute of Geology and Mineralogy, SB RAS, Pr. Akad. Koptyuga, 3, 630090 Novosibirsk (Russian Federation)], E-mail: moroz@uiggm.nsc.ru; Palchik, N.A.; Dar' in, A.V. [Institute of Geology and Mineralogy, SB RAS, Pr. Akad. Koptyuga, 3, 630090 Novosibirsk (Russian Federation)

    2009-05-11

    X-ray fluorescence analysis using synchrotron radiation (SRXRF), X-ray powder diffraction, infrared and Raman spectroscopy had been applied for determination of microelemental and mineral composition of the kidney stones, gallstones and salivalities from natives of Novosibirsk and Novosibirsk region, Russia. The relationship between mineral, organic and microelemental composition of pathogenic calcilus was shown.

  4. The use of X-ray diffraction for analyzing biomodification of crystalline cellulose by wood decay fungi

    DEFF Research Database (Denmark)

    Howell, Caitlin; Hastrup, Anne Christine Steenkjær; Jellison, Jody

    2007-01-01

    X-ray diffraction (XRD) is based on the creation of an interference pattern by x-rays when they encounter a regularly spaced matrix. In wood, this process has been used to determine, among other things, the average width of the cellulose microcrystals, the percent of crystalline cellulose within...

  5. Time-resolved X-ray diffraction with accelerator- and laser-plasma-based X-ray sources

    Energy Technology Data Exchange (ETDEWEB)

    Nicoul, Matthieu

    2010-09-01

    Femtosecond X-ray pulses are a powerful tool to investigate atomic motions triggered by femtosecond pump pulses. This thesis is dedicated to the production of such pulses and their use in optical pump - X-ray probe measurement. This thesis describes the laser-plasma-based sources available at the University of Duisburg-Essen. Part of it consists of the description of the design, built-up and characterization of a new ''modular'' X-ray source dedicated to optimize the X-ray flux onto the sample under investigation. The acoustic wave generation in femtosecond optically excited semiconductor (gallium arsenide) and metal (gold) was performed using the sources of the University of Duisburg-Essen. The physical answer of the material was modeled by a simple strain model for the semiconductor, pressure model for the metal, in order to gain information on the interplay of the electronic and thermal pressures rising after excitation. Whereas no reliable information could be obtain in gallium arsenide (principally due to the use of a bulk), the model for gold achieved very good agreement, providing useful information. The relaxation time of the electron to lattice energy was found to be (5.0{+-}0.3) ps, and the ratio of the Grueneisen parameters was found to be {gamma}{sub e} / {gamma}{sub i} = (0.5{+-}0.1). This thesis also describes the Sub-Picosecond Pulse Source (SPPS) which existed at the (formally) Stanford Linear Accelerator Center, an accelerator-based X-ray source, and two measurements performed with it. The first one is the detailed investigation of the phonon softening of the A{sub 1g} mode launch in bismuth upon fluence excitation. Detailed information concerning the new equilibrium position and phonon frequency were obtained over extended laser pump fluences. The second measurement concerned the study of the liquid phase dynamics in a newly formed liquid phase following ultrafast melting in indium antimonide. The formation of the liquid phase

  6. Surface structure of Bi2Se3(111) determined by low-energy electron diffraction and surface x-ray diffraction

    DEFF Research Database (Denmark)

    dos Reis, Diogo Duarte; Barreto, Lucas; Bianchi, Marco

    2013-01-01

    The surface structure of the prototypical topological insulator Bi2Se3 is determined by low-energy electron diffraction and surface x-ray diffraction at room temperature. Both approaches show that the crystal is terminated by an intact quintuple layer. Specifically, an alternative termination by ...... by a bismuth bilayer is ruled out. Surface relaxations obtained by both techniques are in good agreement with each other and found to be small. This includes the relaxation of the van der Waals gap between the first two quintuple layers....

  7. Anisotropic Thermal Expansion of Zirconium Diboride: An Energy-Dispersive X-Ray Diffraction Study

    Directory of Open Access Journals (Sweden)

    William A. Paxton

    2016-01-01

    Full Text Available Zirconium diboride (ZrB2 is an attractive material due to its thermal and electrical properties. In recent years, ZrB2 has been investigated as a superior replacement for sapphire when used as a substrate for gallium nitride devices. Like sapphire, ZrB2 has an anisotropic hexagonal structure which defines its directionally dependent properties. However, the anisotropic behavior of ZrB2 is not well understood. In this paper, we use energy-dispersive synchrotron X-ray diffraction to measure the thermal expansion of polycrystalline ZrB2 powder from 300 to 1150 K. Nine Bragg reflections are fit using Pseudo-Voigt peak profiles and used to compute the a and c lattice parameters using a nonlinear least-squares approximation. The temperature-dependent instantaneous thermal expansion coefficients are determined for each a-axis and c-axis direction and are described by the following equations: αa = (4.1507×10-6 + 5.1086 × 10-9(T-293.15/(1+4.1507 × 10-6(T-293.15 + 2.5543×10-9(T-293.152 and αc = (4.5374×10-6 + 4.3004×10-9(T-293.15/(1+4.5374×10-6(T-293.15 + 2.1502×10-9(T-293.152. Our results are within range of previously reported values but describe the temperature anisotropy in more detail. We show that anisotropic expansion coefficients converge to the same value at about 780 K and diverge at higher temperatures. Results are compared with other reported values.

  8. Study of archaeological iron objects by PGAA, Mössbauer spectroscopy and X-ray diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Wagner, F. E., E-mail: fwagner@tum.de [Technische Universität München, Physik- Department E15 (Germany); Gebhard, R. [Archäologische Staatssammlung München (Germany); Häusler, W.; Wagner, U. [Technische Universität München, Physik- Department E15 (Germany); Albert, P.; Hess, H. [Archäologische Staatssammlung München (Germany); Révay, Z.; Kudejová, P.; Kleszcz, K. [Technische Universität München, Forschungsneutronenquelle Heinz Maier-Leibnitz (FRM II) (Germany)

    2016-12-15

    Archaeological iron objects often corrode rapidly after their excavation, even though they have survived long times of burial in the ground. Chlorine that accumulates during burial is thought to play a major role in this destructive post-excavation corrosion. It is therefore important for the conservation of such objects to determine the chlorine content in a non-destructive manner and, if necessary, to remove the chlorine from the artefacts by appropriate methods. Such methods are leaching in alkaline solutions or heating in a reducing atmosphere at temperatures up to 800 {sup ∘}C. We have studied the efficiency of the heating method using prompt gamma activation analysis (PGAA) for monitoring the Cl content and Mössbauer spectroscopy at room temperature (RT) and 4.2 K as well as X-ray diffraction to study the mineralogical transformations of the rust layers. The heat treatments were performed a N{sub 2}/H{sub 2} (90/10) mixture at temperatures up to 750 {sup ∘}C. As test specimens sections of iron rods from the Celtic oppidum of Manching (Bavaria) were used. The initial Cl contents of the pieces varied in the range of several hundred ppm, referring to the iron mass. Annealing for 24 h at 350, 550 and 750 {sup ∘}C was found to reduce the Cl contents of the specimens, to about 70, 30 and 15 % of the original values, respectively. The rust consists mainly of goethite with admixtures of magnetite, lepidocrocite and akaganeite, which is thought to be a major carrier of chlorine, probably together with iron chlorides. Much of the goethite is so fine-grained that it does not split magnetically at RT. Annealing converts the rust mainly to maghemite at 350 {sup ∘}C, to magnetite at 550 {sup ∘}C and to wüstite plus magnetite and metallic iron at 750 {sup ∘}C. Pure akaganeite behaves in nearly the same manner.

  9. RASOR: An advanced instrument for soft x-ray reflectivity and diffraction

    Science.gov (United States)

    Beale, T. A. W.; Hase, T. P. A.; Iida, T.; Endo, K.; Steadman, P.; Marshall, A. R.; Dhesi, S. S.; van der Laan, G.; Hatton, P. D.

    2010-07-01

    We report the design and construction of a novel soft x-ray diffractometer installed at Diamond Light Source. The beamline endstation RASOR is constructed for general users and designed primarily for the study of single crystal diffraction and thin film reflectivity. The instrument is comprised of a limited three circle (θ, 2θ, and χ) diffractometer with an additional removable rotation (ϕ) stage. It is equipped with a liquid helium cryostat, and post-scatter polarization analysis. Motorized motions are provided for the precise positioning of the sample onto the diffractometer center of rotation, and for positioning the center of rotation onto the x-ray beam. The functions of the instrument have been tested at Diamond Light Source, and initial test measurements are provided, demonstrating the potential of the instrument.

  10. Synchrotron X-ray diffraction and fluorescence study of the astrolabe

    Energy Technology Data Exchange (ETDEWEB)

    Notis, Michael [Lehigh University, Bethlehem, PA (United States); Newbury, Brian [ExxonMobil Development Company, Houston, TX (United States); Stephenson, Bruce [Adler Planetarium and Astronomy Museum, Chicago, IL (United States); Stephenson, G.B. [Argonne National Laboratory, Argonne, IL (United States)

    2013-04-15

    The astrolabe is an ancient analogue astronomical computing device used for calculations relating to position and time of the observer's location. In its most common form (the planispheric astrolabe), it consists of an engraved plate or series of plates held together and pinned in a housing, the assembly usually being made of brass. The present study describes the use of X-ray diffraction (XRD) and X-ray fluorescence (XRF) in a synchrotron to elucidate the composition of, and fabrication techniques used for, the major component parts of the astrolabe. The synchrotron XRF studies are compared to similar studies made with a handheld XRF instrument and the advantages and disadvantages of both approaches are discussed. (orig.)

  11. Synchrotron X-ray diffraction and fluorescence study of the astrolabe

    Science.gov (United States)

    Notis, Michael; Newbury, Brian; Stephenson, Bruce; Stephenson, G. Brian

    2013-04-01

    The astrolabe is an ancient analogue astronomical computing device used for calculations relating to position and time of the observer's location. In its most common form (the planispheric astrolabe), it consists of an engraved plate or series of plates held together and pinned in a housing, the assembly usually being made of brass. The present study describes the use of X-ray diffraction (XRD) and X-ray fluorescence (XRF) in a synchrotron to elucidate the composition of, and fabrication techniques used for, the major component parts of the astrolabe. The synchrotron XRF studies are compared to similar studies made with a handheld XRF instrument and the advantages and disadvantages of both approaches are discussed.

  12. X-ray diffraction results from Mars Science Laboratory: mineralogy of Rocknest at Gale crater.

    Science.gov (United States)

    Bish, D L; Blake, D F; Vaniman, D T; Chipera, S J; Morris, R V; Ming, D W; Treiman, A H; Sarrazin, P; Morrison, S M; Downs, R T; Achilles, C N; Yen, A S; Bristow, T F; Crisp, J A; Morookian, J M; Farmer, J D; Rampe, E B; Stolper, E M; Spanovich, N

    2013-09-27

    The Mars Science Laboratory rover Curiosity scooped samples of soil from the Rocknest aeolian bedform in Gale crater. Analysis of the soil with the Chemistry and Mineralogy (CheMin) x-ray diffraction (XRD) instrument revealed plagioclase (~An57), forsteritic olivine (~Fo62), augite, and pigeonite, with minor K-feldspar, magnetite, quartz, anhydrite, hematite, and ilmenite. The minor phases are present at, or near, detection limits. The soil also contains 27 ± 14 weight percent x-ray amorphous material, likely containing multiple Fe(3+)- and volatile-bearing phases, including possibly a substance resembling hisingerite. The crystalline component is similar to the normative mineralogy of certain basaltic rocks from Gusev crater on Mars and of martian basaltic meteorites. The amorphous component is similar to that found on Earth in places such as soils on the Mauna Kea volcano, Hawaii.

  13. Structure determination of thin CoFe films by anomalous x-ray diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Gloskovskii, Andrei; Stryganyuk, Gregory; Ouardi, Siham [Institut fuer Anorganische und Analytische Chemie, Johannes Gutenberg-Universitaet, 55099 Mainz (Germany); Fecher, Gerhard H.; Felser, Claudia [Institut fuer Anorganische und Analytische Chemie, Johannes Gutenberg-Universitaet, 55099 Mainz (Germany); Max Planck Institute for Chemical Physics of Solids, D-01187 Dresden (Germany); Hamrle, Jaroslav; Pistora, Jaromir [Department of Physics and Nanotechnology Centre, VSB-Technical University of Ostrava, 70833 Ostrava (Czech Republic); Bosu, Subrojati; Saito, Kesami; Sakuraba, Yuya; Takanashi, Koki [Institute for Materials Research (IMR), Tohoku University, Sendai 980-8577 (Japan)

    2012-10-01

    This work reports on the investigation of structure-property relationships in thin CoFe films grown on MgO. Because of the very similar scattering factors of Fe and Co, it is not possible to distinguish the random A2 (W-type) structure from the ordered B2 (CsCl-type) structure with commonly used x-ray sources. Synchrotron radiation based anomalous x-ray diffraction overcomes this problem. It is shown that as grown thin films and 300 K post annealed films exhibit the A2 structure with a random distribution of Co and Fe. In contrast, films annealed at 400 K adopt the ordered B2 structure.

  14. Pathway of a damaging mechanism - Analyzing chloride attack by synchrotron based X-ray diffraction

    Science.gov (United States)

    Schlegel, M. C.; Stroh, J.; Malaga, K.; Meng, B.; Panne, U.; Emmerling, F.

    2015-06-01

    Typically, the changes of the phase compositions due to the chemical attack are studied in-situ only by chemical analysis or microscopy. In this study, the chloride transport and binding in the cement matrix in different cementitious materials was analyzed by synchrotron based X-ray diffraction (SyXRD) and energy dispersive X-ray spectroscopy (EDX). Sample materials consisting of cement paste were embedded in high concentrated sodium chloride solution over different time spans. Afterwards, the phase and chemical compositions were determined. The high spatial resolution and the information about the chloride distribution offer a detailed view of chloride binding in the cement matrix and allow the conclusions about the degradation mechanisms. The results are discussed related to the influence of different supplementary cementitious materials on the damaging mechanism.

  15. Automated high pressure cell for pressure jump x-ray diffraction.

    Science.gov (United States)

    Brooks, Nicholas J; Gauthe, Beatrice L L E; Terrill, Nick J; Rogers, Sarah E; Templer, Richard H; Ces, Oscar; Seddon, John M

    2010-06-01

    A high pressure cell for small and wide-angle x-ray diffraction measurements of soft condensed matter samples has been developed, incorporating a fully automated pressure generating network. The system allows both static and pressure jump measurements in the range of 0.1-500 MPa. Pressure jumps can be performed as quickly as 5 ms, both with increasing and decreasing pressures. Pressure is generated by a motorized high pressure pump, and the system is controlled remotely via a graphical user interface to allow operation by a broad user base, many of whom may have little previous experience of high pressure technology. Samples are loaded through a dedicated port allowing the x-ray windows to remain in place throughout an experiment; this facilitates accurate subtraction of background scattering. The system has been designed specifically for use at beamline I22 at the Diamond Light Source, United Kingdom, and has been fully integrated with the I22 beamline control systems.

  16. Source assemblage types for cratonic diamonds from X-ray synchrotron diffraction

    Science.gov (United States)

    Nestola, F.; Alvaro, M.; Casati, M. N.; Wilhelm, H.; Kleppe, A. K.; Jephcoat, A. P.; Domeneghetti, M. C.; Harris, J. W.

    2016-11-01

    Three single crystals of clinopyroxene trapped within three different gem-quality diamonds from the Udachnaya kimberlite (Siberia, Russia) were analysed in situ by single-crystal synchrotron X-ray diffraction in order to obtain information on their chemical composition and infer source assemblage type. A non-destructive approach was used with high-energy (≈ 60 keV; λ ≈ 0.206 Å) at I15, the extreme-conditions beamline at Diamond Light Source. A dedicated protocol was used to center the mineral inclusions located deep inside the diamonds in the X-ray beam. Our results reveal that two of the inclusions can be associated with peridotitic paragenesis whereas the third is eclogitic. This study also demonstrates that this non-destructive experimental approach is extremely efficient in evaluating the origin of minerals trapped in their diamond hosts.

  17. RASOR: an advanced instrument for soft x-ray reflectivity and diffraction.

    Science.gov (United States)

    Beale, T A W; Hase, T P A; Iida, T; Endo, K; Steadman, P; Marshall, A R; Dhesi, S S; van der Laan, G; Hatton, P D

    2010-07-01

    We report the design and construction of a novel soft x-ray diffractometer installed at Diamond Light Source. The beamline endstation RASOR is constructed for general users and designed primarily for the study of single crystal diffraction and thin film reflectivity. The instrument is comprised of a limited three circle (theta, 2theta, and chi) diffractometer with an additional removable rotation (phi) stage. It is equipped with a liquid helium cryostat, and post-scatter polarization analysis. Motorized motions are provided for the precise positioning of the sample onto the diffractometer center of rotation, and for positioning the center of rotation onto the x-ray beam. The functions of the instrument have been tested at Diamond Light Source, and initial test measurements are provided, demonstrating the potential of the instrument.

  18. Monitoring protein precipitates by in-house X-ray powder diffraction

    DEFF Research Database (Denmark)

    Ståhl, Kenny; Frankær, Christian Grundahl; Petersen, Jakob

    2013-01-01

    Powder diffraction from protein powders using in-house diffractometers is an effective tool for identification and monitoring of protein crystal forms and artifacts. As an alternative to conventional powder diffractometers a single crystal diffractometer equipped with an X-ray micro-source can...... of protein data sets in the database some problems can be foreseen due to the large number of overlapping peaks in the low-angle region, and small differences in unit cell parameters between pdb-data and powder data. It is suggested that protein entries are supplied with more searchable keywords as protein...... be used to collect powder patterns from 1 l samples. Using a small-angle X-ray scattering (SAXS) camera it is possible to collect data within minutes. A streamlined program has been developed for the calculation of powder patterns from pdb-coordinates, and includes correction for bulk-solvent. A number...

  19. Imaging at the X-ray Frontier: Coherent Diffraction Imaging (CDI) for Nano and Bioscience

    Science.gov (United States)

    Miao, Jianwei (John)

    2013-03-01

    For centuries, lens-based microscopy, such as light, phase-contrast, fluorescence, confocal and electron microscopy, has played an important role in the evolution of modern sciences and technologies. In 1999, a novel form of microscopy, i.e. coherent diffraction imaging (also termed coherent diffraction microscopy or lensless imaging) was developed and transformed our traditional view of microscopy, in which the diffraction pattern of a noncrystalline object or a nanocrystal is first measured and then directly phased to obtain a high resolution image. The well-known phase problem is solved by the oversampling method in combination with iterative algorithms whose principle can be traced back to the Shannon sampling theorem. In this talk, I will briefly discuss the principle of coherent diffraction imaging and illustrate its broad application in nano and bioscience by using synchrotron radiation, high harmonic generation and X-ray free electron lasers.

  20. In-situ study of the growth of CuO nanowires by energy dispersive X-ray diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Srivastava, Himanshu; Ganguli, Tapas; Deb, S. K. [Indus Synchrotrons Utilization Division, Raja Ramanna Centre for Advanced technology, Indore-452013 (India); Sant, Tushar; Poswal, Himanshu; Sharma, S. M. [High Pressure and Synchrotron Physics Division, Bhabha Atomic Research Centre, Mumbai (India)

    2013-02-05

    Growth of CuO nanowires by annealing method has been studied in-situ by grazing incidence Energy Dispersive X-ray Diffraction (EDXRD) technique on Indus-2. It was observed that Cu slowly oxidized to Cu{sub 2}O and finally to CuO. The data was taken as a function of time at two annealing temperatures 500 Degree-Sign C where nanowires form and 300 Degree-Sign C where nanowires don't form. We found that the strain in the CuO layer may be a principal factor for the spontaneous growth of nanowires in annealing method.

  1. The Oxford-Diamond In Situ Cell for studying chemical reactions using time-resolved X-ray diffraction.

    Science.gov (United States)

    Moorhouse, Saul J; Vranješ, Nenad; Jupe, Andrew; Drakopoulos, Michael; O'Hare, Dermot

    2012-08-01

    A versatile, infrared-heated, chemical reaction cell has been assembled and commissioned for the in situ study of a range of chemical syntheses using time-resolved energy-dispersive X-ray diffraction (EDXRD) on Beamline I12 at the Diamond Light Source. Specialized reactor configurations have been constructed to enable in situ EDXRD investigation of samples under non-ambient conditions. Chemical reactions can be studied using a range of sample vessels such as alumina crucibles, steel hydrothermal autoclaves, and glassy carbon tubes, at temperatures up to 1200 °C.

  2. The Oxford-Diamond In Situ Cell for studying chemical reactions using time-resolved X-ray diffraction

    Science.gov (United States)

    Moorhouse, Saul J.; Vranješ, Nenad; Jupe, Andrew; Drakopoulos, Michael; O'Hare, Dermot

    2012-08-01

    A versatile, infrared-heated, chemical reaction cell has been assembled and commissioned for the in situ study of a range of chemical syntheses using time-resolved energy-dispersive X-ray diffraction (EDXRD) on Beamline I12 at the Diamond Light Source. Specialized reactor configurations have been constructed to enable in situ EDXRD investigation of samples under non-ambient conditions. Chemical reactions can be studied using a range of sample vessels such as alumina crucibles, steel hydrothermal autoclaves, and glassy carbon tubes, at temperatures up to 1200 °C.

  3. Structural analysis of GaN using high-resolution X-ray diffraction at variable temperatures; Analyse struktureller Eigenschaften von GaN mittels hochaufloesender Roentgenbeugung bei variabler Messtemperatur

    Energy Technology Data Exchange (ETDEWEB)

    Roder, C.

    2007-02-26

    The main topic of this thesis was the study of stress phenomena in GaN layers by application of high-resolution X-ray diffractometry at variable measurement temperature. For this a broad spectrum of different GaN samples was studied, which extended from bulk GaN crystals as well as thick c-plane oriented HVPE-GaN layers on c-plane sapphire over laterlaly overgrown c-plane GaN Layers on Si(111) substrates toon-polar a-plnae GaN layers on r-plane sapphire. The main topic of the measurements was the determination of the lattice parameters. Supplementarily the curvature of the waver as well as the excitonic resosance energies were studied by means of photoluminescence respectively photoreflection spectroscopy. By the measurement of the temperature-dependent lattice parameters of different GaN bulk crystals for the first time a closed set of thermal-expansion coefficients of GaN was determined from 12 to 1205 K with large accuracy. Analoguously the thermal-expansion coefficents of the substrate material sapphire were determinde over a temperature range from 10 to 1166 K.

  4. Determining the C60 molecular arrangement in thin films by means of X-ray diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Elschner, Chris; Levin, Alexandr A.; Leo, Karl; Riede, Moritz [TU Dresden (Germany). Inst. fuer Angewandte Photophysik; Wilde, Lutz [Fraunhofer CNT Dresden (Germany).; Grenzer, Joerg [Helmholtz-Zentrum Dresden-Rossendorf (Germany); Schroer, Christian [TU Dresden (Germany). Inst. fuer Strukturphysik

    2011-10-15

    The electrical and optical properties of molecular thin films are widely used, for instance in organic electronics, and depend strongly on the molecular arrangement of the organic layers. It is shown here how atomic structural information can be obtained from molecular films without further knowledge of the single-crystal structure. C60 fullerene was chosen as a representative test material. A 250 nm C60 film was investigated by grazing-incidence X-ray diffraction and the data compared with a Bragg-Brentano X-ray diffraction measurement of the corresponding C60 powder. The diffraction patterns of both powder and film were used to calculate the pair distribution function (PDF), which allowed an investigation of the short-range order of the structures. With the help of the PDF, a structure model for the C60 molecular arrangement was determined for both C60 powder and thin film. The results agree very well with a classical whole-pattern fitting approach for the C60 diffraction patterns. (orig.)

  5. Revisit of alpha-chitin crystal structure using high resolution X-ray diffraction data.

    Science.gov (United States)

    Sikorski, Pawel; Hori, Ritsuko; Wada, Masahisa

    2009-05-11

    High resolution synchrotron X-ray fiber diffraction data recorded from crab tendon chitin have been used to describe the crystal structure of alpha-chitin. Crystal structures at 100 and 300 K have been solved using restrained crystallographic refinement against diffraction intensities measured from the fiber diffraction patterns. The unit cell contains two polymer chains in a 2(1) helix conformation and in the antiparallel orientation. The best agreement between predicated and observed X-ray diffraction intensities is obtained for a model that includes two distinctive conformations of C6-O6 hydroxymethl group. Those conformations are different from what is proposed in the generally accepted alpha-chitin crystal structure (J. Mol. Biol. 1978, 120, 167-181). Based on refined positions of the O6 atoms, a network of hydrogen bonds involving O6 is proposed. This network of hydrogen bonds can explain the main features of the polarized FTIR spectra of alpha-chitin and sheds some light on the origin of splitting of the amide I band observed on alpha-chitin IR spectra.

  6. Calculated efficiencies of three-material low stress coatings for diffractive x-ray transmission optics

    Energy Technology Data Exchange (ETDEWEB)

    Kubec, Adam, E-mail: adam.kubec@iws.fraunhofer.de; Braun, Stefan; Gawlitza, Peter; Menzel, Maik; Leson, Andreas [Fraunhofer IWS Dresden, Winterbergstr. 28, 01277 Dresden (Germany)

    2016-07-27

    Diffractive X-ray optical elements made by thin film coating techniques such as multilayer Laue lenses (MLL) and multilayer zone plates (MZP) are promising approaches to achieve resolutions in hard X-ray microscopy applications of less than 10 nm. The challenge is to make a lens with a large numerical aperture on the one hand and a decent working distance on the other hand. One of the limiting factors with the coated structures is the internal stress in the films, which can lead to significant bending of the substrate and various types of unwanted diffraction effects. Several approaches have been discussed to overcome this challenge. One of these is a three-material combination such as Mo/MoSi{sub 2}/Si, where four single layers per period are deposited. Mo and Si represent the absorber and spacer in this case while MoSi{sub 2} forms a diffusion barrier; in addition the thicknesses of absorber and spacer are chosen to minimize residual stress of the overall coating. Here the diffraction efficiency as well as the profile of the beam in the focal plane are discussed in order to find a tradeoff between lowest residual stress and best diffraction properties.

  7. Diffraction and imaging study of imperfections of crystallized lysozyme with coherent X-rays

    Science.gov (United States)

    Hu, Z. W.; Chu, Y. S.; Lai, B.; Thomas, B. R.; Chernov, A. A.

    2004-01-01

    Phase-contrast X-ray diffraction imaging and high-angular-resolution diffraction combined with phase-contrast radiographic imaging were employed to characterize defects and perfection of a uniformly grown tetragonal lysozyme crystal in the symmetric Laue case. The full-width at half-maximum (FWHM) of a 4 4 0 rocking curve measured from the original crystal was approximately 16.7 arcsec and imperfections including line defects, inclusions and other microdefects were observed in the diffraction images of the crystal. The observed line defects carry distinct dislocation features running approximately along the growth front and have been found to originate mostly in a central growth area and occasionally in outer growth regions. Inclusions of impurities or formations of foreign particles in the central growth region are resolved in the images with high sensitivity to defects. Slow dehydration led to the broadening of a fairly symmetric 4 4 0 rocking curve by a factor of approximately 2.6, which was primarily attributed to the dehydration-induced microscopic effects that are clearly shown in X-ray diffraction images. The details of the observed defects and the significant change in the revealed microstructures with drying provide insight into the nature of imperfections, nucleation and growth, and the properties of protein crystals.

  8. X-ray, synchrotron, and neutron diffraction analysis of Roman cavalry parade helmet fragment

    Energy Technology Data Exchange (ETDEWEB)

    Smrcok, L' . [Institute of Inorganic Chemistry, Slovak Academy of Sciences, Dubravska cesta 9, 84536 Bratislava (Slovakia); Petrik, I. [Geological Institute, Slovak Academy of Sciences, Dubravska cesta 9, 84005 Bratislava (Slovakia); Langer, V. [Environmental Inorganic Chemistry, Chalmers University of Technology, 412 96 Gothenburg (Sweden); Filinchuk, Y. [Swiss-Norwegian Beam Lines, European Synchrotron Radiation Facility, 6 rue Jules Horowitz, BP-220, 38043 Grenoble CEDEX (France); Beran, P. [Nuclear Physics Institute ASCR v.v.i. and Research Centre Rez Ltd., 25068 Rez (Czech Republic)

    2010-10-15

    A partially corroded fragment of the neck guard of a Roman cavalry helmet excavated in the former military camp of Gerulata, a part of the Limes Romanus on the River Danube, was analysed by laboratory X-ray, synchrotron and neutron powder diffraction. The approximate phase composition determined by the neutron diffraction of the bulk, 82% (wt) of the copper alloy phase, 12 % (wt) of cuprite and 6% of nantokite indicate a significant degree of corrosion of the artefact. Elemental EDX analysis of cleaned surface showed that the chemical composition of the original alloy is 78 to 82 % (wt) of Cu and 21.4 to 16.5 % of Zn with minute amounts of Sn, Si and S. High contents of Cu and Zn with the negligible amount of Sn showed that the body of the helmet was made of brass and not of bronze as expected before. The amount of zinc in the copper alloy calculated from the refined lattice parameter agrees fairly well with the value determined by EDX. The most abundant phase in the synchrotron powder diffraction pattern of the corrosion products scrapped from the artefact is cuprite, but presence of atacamite, malachite, brochantite, nantokite, mixed Cu-Zn hydroxyl carbonates and probably also of simonkolleite (Zn{sub 5}(OH){sub 8}Cl{sub 2}.H{sub 2}O) have been detected. In contrast, the X-ray pattern taken directly from the surface of the artefact is dominated by atacamite with some traces of malachite and quartz. Because the penetration depth of laboratory X-rays is in order of tens of microns, the phase analysis based only on a diffraction pattern taken from a surface can lead to erroneous conclusions concerning the phase composition of the patina. (copyright 2010 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  9. Advanced combined application of micro-X-ray diffraction/micro-X-ray fluorescence with conventional techniques for the identification of pictorial materials from Baroque Andalusia paintings.

    Science.gov (United States)

    Herrera, L K; Montalbani, S; Chiavari, G; Cotte, M; Solé, V A; Bueno, J; Duran, A; Justo, A; Perez-Rodriguez, J L

    2009-11-15

    The process of investigating paintings includes the identification of materials to solve technical and historical art questions, to aid in the deduction of the original appearance, and in the establishment of the chemical and physical conditions for adequate restoration and conservation. In particular, we have focused on the identification of several samples taken from six famous canvases painted by Pedro Atanasio Bocanegra, who created a very special collection depicting the life of San Ignacio, which is located in the church of San Justo y Pastor of Granada, Spain. The characterization of the inorganic and organic compounds of the textiles, preparation layers, and pictorial layers have been carried out using an XRD diffractometer, SEM observations, EDX spectrometry, FT-IR spectrometry (both in reflection and transmission mode), pyrolysis/gas chromatography/mass spectrometry and synchrotron-based micro-X-ray techniques. In this work, the advantages over conventional X-ray diffraction of using combined synchrotron-based micro-X-ray diffraction and micro-X-ray fluorescence in the identification of multi-layer paintings is demonstrated.

  10. X-ray Diffraction from Isolated and Strongly Aligned Gas-Phase Molecules with a Free-Electron Laser

    DEFF Research Database (Denmark)

    Küpper, Jochen; Stern, Stephan; Holmegaard, Lotte

    2014-01-01

    imaging of distinct structures of individual, isolated gas-phase molecules. We confirm several key ingredients of single molecule diffraction experiments: the abilities to detect and count individual scattered x-ray photons in single shot diffraction data, to deliver state-selected, e. g., structural......We report experimental results on x-ray diffraction of quantum-state-selected and strongly aligned ensembles of the prototypical asymmetric rotor molecule 2,5-diiodobenzonitrile using the Linac Coherent Light Source. The experiments demonstrate first steps toward a new approach to diffractive......-isomer-selected, ensembles of molecules to the x-ray interaction volume, and to strongly align the scattering molecules. Our approach, using ultrashort x-ray pulses, is suitable to study ultrafast dynamics of isolated molecules....

  11. Kinetic products in coordination networks: ab initio X-ray powder diffraction analysis.

    Science.gov (United States)

    Martí-Rujas, Javier; Kawano, Masaki

    2013-02-19

    Porous coordination networks are materials that maintain their crystal structure as molecular "guests" enter and exit their pores. They are of great research interest with applications in areas such as catalysis, gas adsorption, proton conductivity, and drug release. As with zeolite preparation, the kinetic states in coordination network preparation play a crucial role in determining the final products. Controlling the kinetic state during self-assembly of coordination networks is a fundamental aspect of developing further functionalization of this class of materials. However, unlike for zeolites, there are few structural studies reporting the kinetic products made during self-assembly of coordination networks. Synthetic routes that produce the necessary selectivity are complex. The structural knowledge obtained from X-ray crystallography has been crucial for developing rational strategies for design of organic-inorganic hybrid networks. However, despite the explosive progress in the solid-state study of coordination networks during the last 15 years, researchers still do not understand many chemical reaction processes because of the difficulties in growing single crystals suitable for X-ray diffraction: Fast precipitation can lead to kinetic (metastable) products, but in microcrystalline form, unsuitable for single crystal X-ray analysis. X-ray powder diffraction (XRPD) routinely is used to check phase purity, crystallinity, and to monitor the stability of frameworks upon guest removal/inclusion under various conditions, but rarely is used for structure elucidation. Recent advances in structure determination of microcrystalline solids from ab initio XRPD have allowed three-dimensional structure determination when single crystals are not available. Thus, ab initio XRPD structure determination is becoming a powerful method for structure determination of microcrystalline solids, including porous coordination networks. Because of the great interest across scientific

  12. X-ray emission from high temperature plasmas

    Science.gov (United States)

    Harries, W. L.

    1974-01-01

    X-rays from a 25-hJ plasma focus apparatus were observed with pinhole cameras. The cameras consist of 0.4 mm diameter pinholes in 2 cm thick lead housing enclosing an X-ray intensifying screen at the image plane. Pictures recorded through thin aluminum foils or plastic sheets for X-ray energies sub gamma smaller than 15 keV show distributed X-ray emissions from the focussed plasma and from the anode surface. However, when thick absorbers are used, radial filamentary structure in the X-ray emission from the anode surface is revealed. Occasionally larger structures are observed in addition to the filaments. Possible mechanisms for the filamentary structure are discussed.

  13. Filming nuclear dynamics of iodine using x-ray diffraction at the LCLS

    Science.gov (United States)

    Ware, Matthew; Natan, Adi; Glownia, James; Cryan, James; Bucksbaum, Phil

    2017-04-01

    We will provide an overview of our analysis of the nuclear dynamics of iodine. At the LCLS, we pumped a gas cell of iodine with a weak 520nm, 50 fs pulse, and the nuclear dynamics are then probed with 9 keV, 40 fs x-rays with variable time delay. This allows us to simultaneously image nuclear wavepackets on the dissociating A state, on the bound B state, and even Raman wavepackets in the ground electronic state. We will explain at length how we isolate each of these signals using a Legendre decomposition of our x-ray data and the selection rules for each of the transitions. Likewise, we will discuss how we convert the x-ray diffraction patterns into real-space movies of the nuclear dynamics. Research supported by the U.S. Department of Energy, Office of Basic Energy Sciences, Atomic, Molecular, and Optical Science Program. Use of LCLS supported under DOE Contract No. DE-AC02-76F00515.

  14. Integrating macromolecular X-ray diffraction data with the graphical user interface iMosflm.

    Science.gov (United States)

    Powell, Harold R; Battye, T Geoff G; Kontogiannis, Luke; Johnson, Owen; Leslie, Andrew G W

    2017-07-01

    X-ray crystallography is the predominant source of structural information for biological macromolecules, providing fundamental insights into biological function. The availability of robust and user-friendly software to process the collected X-ray diffraction images makes the technique accessible to a wider range of scientists. iMosflm/MOSFLM (http://www.mrc-lmb.cam.ac.uk/harry/imosflm) is a software package designed to achieve this goal. The graphical user interface (GUI) version of MOSFLM (called iMosflm) is designed to guide inexperienced users through the steps of data integration, while retaining powerful features for more experienced users. Images from almost all commercially available X-ray detectors can be handled using this software. Although the program uses only 2D profile fitting, it can readily integrate data collected in the 'fine phi-slicing' mode (in which the rotation angle per image is less than the crystal mosaic spread by a factor of at least 2), which is commonly used with modern very fast readout detectors. The GUI provides real-time feedback on the success of the indexing step and the progress of data processing. This feedback includes the ability to monitor detector and crystal parameter refinement and to display the average spot shape in different regions of the detector. Data scaling and merging tasks can be initiated directly from the interface. Using this protocol, a data set of 360 images with ∼2,000 reflections per image can be processed in ∼4 min.

  15. Simultaneous X-ray imaging and diffraction study of shock propagation and phase transition in silicon

    Science.gov (United States)

    Galtier, Eric

    2017-06-01

    X-ray phase contrast imaging technique using a free electron laser have observed the propagation of laser-driven shock waves directly inside materials. While providing images with few hundred nanometers spatial resolution, access to more quantitative information like the material density and the various shock front speeds remain challenging due to imperfections in the images limiting the convergence in the reconstruction algorithm. Alternatively, pump-probe X-ray diffraction (XRD) is a robust technique to extract atomic crystalline structure of compressed matter, providing insight into the kinetics of phase transformation and material response to stress. However, XRD by itself is not sufficient to extract the equation of state of the material under study. Here we report on the use of the LCLS free electron laser as a source of a high-resolution X-ray microscopy enabling the direct imaging of shock waves and phase transitions in optically opaque silicon. In this configuration, no algorithm is necessary to extract the material density and the position of the shock fronts. Simultaneously, we probed the crystalline structure via XRD of the various phases in laser compressed silicon. E. Galtier, B. Nagler, H. J. Lee, S. Brown, E. Granados, A. Hashim, E. McBride, A. Mackinnon, I. Nam, J. Zimmerman (SLAC) A. Gleason (Stanford, LANL) A. Higginbotham (University of York) A. Schropp, F. Seiboth (DESY).

  16. Reconstruction of Stress and Composition Profiles from X-ray Diffraction Experiments - How to Avoid Ghost Stresses?

    DEFF Research Database (Denmark)

    Christiansen, Thomas; Somers, Marcel A.J.

    2004-01-01

    On evaluating lattice strain-depth or stress-depth profiles with X-ray diffraction, the variation of the information depth while combining various tilt angles,psi, in combination with lattice spacing gradients leads to artefacts,so-called ghost or fictitious stresses. X-ray diffraction lattice...... method for the evaluation of stress/strain and composition profiles, while minimising the risk for ghost stresses....

  17. Real-time x-ray diffraction measurements of shocked polycrystalline tin and aluminum

    Science.gov (United States)

    Morgan, Dane V.; Macy, Don; Stevens, Gerald

    2008-11-01

    A new, fast, single-pulse x-ray diffraction (XRD) diagnostic for determining phase transitions in shocked polycrystalline materials has been developed. The diagnostic consists of a 37-stage Marx bank high-voltage pulse generator coupled to a needle-and-washer electron beam diode via coaxial cable, producing line and bremsstrahlung x-ray emission in a 35 ns pulse. The characteristic Kα lines from the selected anodes of silver and molybdenum are used to produce the diffraction patterns, with thin foil filters employed to remove the characteristic Kβ line emission. The x-ray beam passes through a pinhole collimator and is incident on the sample with an approximately 3×6 mm2 spot and 1° full width half maximum angular divergence in a Bragg-reflecting geometry. For the experiments described in this report, the angle between the incident beam and the sample surface was 8.5°. A Debye-Scherrer diffraction image was produced on a phosphor located 76 mm from the polycrystalline sample surface. The phosphor image was coupled to a charge-coupled device camera through a coherent fiber-optic bundle. Dynamic single-pulse XRD experiments were conducted with thin foil samples of tin, shock loaded with a 1 mm vitreous carbon back window. Detasheet high explosive with a 2-mm-thick aluminum buffer was used to shock the sample. Analysis of the dynamic shock-loaded tin XRD images revealed a phase transformation of the tin beta phase into an amorphous or liquid state. Identical experiments with shock-loaded aluminum indicated compression of the face-centered-cubic aluminum lattice with no phase transformation.

  18. Identification of cremains using X-ray diffraction spectroscopy and a comparison to trace element analysis.

    Science.gov (United States)

    Bergslien, Elisa T; Bush, Mary; Bush, Peter J

    2008-03-05

    The ability to distinguish human cremains from filler materials can be important in a variety of situations, the most notorious recent example being the Tri-State Crematorium incident. However, the majority of the papers in the recent literature present methods that rely on trace or minor element analysis, usually followed by a statistical or variable cluster analysis, to determine attribution. This approach is inherently risky, as there is significant natural variation in the trace and minor element body burdens within the human population and no real baseline for comparison. Bones and teeth are a form of calcium phosphate that is part of the mineral group apatite, often referred to as bioapatite. X-ray diffraction (XRD) spectroscopy is a technique that is used to identify minerals by their crystalline structures rather than their elemental composition. The members of the mineral group apatite have a highly flexible hexagonal (6/m) structure that is able to incorporate small amounts of a wide variety of elements. However, its structure, and therefore its X-ray diffraction pattern, is distinct from the crystalline structures of all of the commonly reported filler materials, most of which are composed of some combination of Portland cement, limestone aggregate and quartz sand. XRD has several advantages over other analytical techniques for the identification of cremains. It is non-destructive, requires relatively small amounts of material, is unaffected by the elemental variations found in bioapatite, and can be used to semi-quantify the components of a mixture, thus determining the relative level of contamination of a sample. This paper presents the results of X-ray diffraction spectroscopy analysis of human cremains and a variety of common filler materials.

  19. X-ray diffraction analysis of residual stress in zirconia dental composites

    Science.gov (United States)

    Allahkarami, Masoud

    Dental restoration ceramic is a complex system to be characterized. Beside its essential biocompatibility, and pleasant appearance, it requires being mechanically strong in a catastrophic loading environment. Any design is restricted with geometry boundary and material property limits. Inspired by natural teeth, a multilayer ceramic is a smart way of achieving an enhanced restoration. Bi-layers of zirconia core covered by porcelain are known as one of the best multilayer restorations. Residual stresses may be introduced into a bi-layer dental ceramic restoration during its entire manufacturing process due to thermal expansion and elastic property mismatch. It is impossible to achieve a free of residual stresses bi-layer zirconia-porcelain restoration. The idea is to take the advantage of residual stress in design in such a way to prevent the crack initiation and progression. The hypothesis is a compressive residual stress at external contact surface would be enabling the restoration to endure a greater tensile stress. Optimizing the layers thickness, manufacturing process, and validating 3D simulations require development of new techniques of thickness, residual stresses and phase transformation measurement. In the present work, a combined mirco-tomography and finite element based method were adapted for thickness measurement. Two new 2D X-ray diffraction based techniques were adapted for phase transformation area mapping and combined phase transformation and residual stress measurement. Concerning the complex geometry of crown, an efficient method for X-ray diffraction data collection mapping on a given curved surface was developed. Finally a novel method for 3D dimensional x-ray diffraction data collection and visualization were introduced.

  20. Residual stress measurement in textured thin film by grazing-incidence X-ray diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Ma, C.-H.; Huang, J.-H.; Chen, Haydn

    2002-10-15

    Measurements of residual stresses in textured thin films have always been problematic. In this article, a new experimental method using grazing-incidence X-ray diffraction is presented with its principles based upon the conventional sin{sup 2}{psi} method. Instead of using the Bragg-Brentano (B-B) or Seemann-Bohlin geometry, the proposed method utilizes an asymmetrical diffraction geometry for which the X-ray beam is incident at a grazing angle {gamma} to the sample surface, while the angle {psi} is the tilt angle of the sample surface as defined by the conventional sin{sup 2}{psi} method. Basic equations involved in the X-ray residual stress analysis are described, along with exemplified experimental data. Analysis shows that, for an isotropic medium, strain measured using this grazing-incidence geometry assumes a linear relationship with the geometrical parameter cos{sup 2}{alpha} sin{sup 2}{psi}, where the angle {alpha} is a constant and is defined as the Bragg angle at {psi}=0 deg., {theta}{sub o}, minus the grazing incidence angle {gamma}, i.e. {alpha}={theta}{sub o}-{gamma}. The grazing-incidence diffraction geometry effectively increases the irradiation volume from a thin-film specimen, thereby giving rise to higher intensity for high-angle Bragg peaks than the conventional B-B geometry. The proposed analysis has another advantage, in that the inhomogeneous sample casts little effect on the residual stress results when compared to the traditional sin{sup 2}{psi} method.

  1. Fundamental parameters approach applied to focal construct geometry for X-ray diffraction

    Science.gov (United States)

    Rogers, K.; Evans, P.; Prokopiou, D.; Dicken, A.; Godber, S.; Rogers, J.

    2012-10-01

    A novel geometry for the acquisition of powder X-ray diffraction data, referred to as focal construct geometry (FCG), is presented. Diffraction data obtained by FCG have been shown to possess significantly enhanced intensity due to the hollow tube beam arrangement utilized. In contrast to conventional diffraction, the detector is translated to collect images along a primary axis and record the location of Bragg maxima. These high intensity condensation foci are unique to FCG and appear due to the convergence of Debye cones at single points on the primary axis. This work focuses on a two dimensional, fundamental parameter's approach to simulate experimental data and subsequently aid with interpretation. This convolution method is shown to favorably reproduce the experimental diffractograms and can also accommodate preferred orientation effects in some circumstances.

  2. Setup for in situ X-ray diffraction studies of thin film growth by magnetron sputtering

    CERN Document Server

    Ellmer, K; Weiss, V; Rossner, H

    2001-01-01

    A novel method is described for the in situ-investigation of nucleation and growth of thin films during magnetron sputtering. Energy dispersive X-ray diffraction with synchrotron light is used for the structural analysis during film growth. An in situ-magnetron sputtering chamber was constructed and installed at a synchrotron radiation beam line with a bending magnet. The white synchrotron light (1-70 keV) passes the sputtering chamber through Kapton windows and hits one of the substrates on a four-fold sample holder. The diffracted beam, observed under a fixed diffraction angle between 3 deg. and 10 deg., is energy analyzed by a high purity Ge-detector. The in situ-EDXRD setup is demonstrated for the growth of tin-doped indium oxide (ITO) films prepared by reactive magnetron sputtering from a metallic target.

  3. Purification, crystallization and preliminary X-ray diffraction analysis of royal palm tree (Roystonea regia) peroxidase

    Energy Technology Data Exchange (ETDEWEB)

    Watanabe, Leandra; Nascimento, Alessandro S. [Instituto de Física de São Carlos, Departamento de Física e Informática, Universidade de São Paulo, Avenida Trabalhador São Carlense 400, CEP 13566-590 São Carlos, SP (Brazil); Zamorano, Laura S. [Departamento de Química Física, Facultad de Química, Universidad de Salamanca, 37008 Salamanca (Spain); Shnyrov, Valery L. [Departamento de Bioquímica y Biología Molecular, Facultad de Biología, Universidad de Salamanca, 37007 Salamanca (Spain); Polikarpov, Igor, E-mail: ipolikarpov@if.sc.usp.br [Instituto de Física de São Carlos, Departamento de Física e Informática, Universidade de São Paulo, Avenida Trabalhador São Carlense 400, CEP 13566-590 São Carlos, SP (Brazil); Laboratório Nacional de Luz Síncrotron, Campinas, SP (Brazil)

    2007-09-01

    The purification, crystallization, X-ray diffraction data acquisition and molecular-replacement results of royal palm tree (R. regia) peroxidase are described. Royal palm tree peroxidase (RPTP), which was isolated from Roystonea regia leaves, has an unusually high stability that makes it a promising candidate for diverse applications in industry and analytical chemistry [Caramyshev et al. (2005 ▶), Biomacromolecules, 6, 1360–1366]. Here, the purification and crystallization of this plant peroxidase and its X-ray diffraction data collection are described. RPTP crystals were obtained by the hanging-drop vapour-diffusion method and diffraction data were collected to a resolution of 2.8 Å. The crystals belong to the trigonal space group P3{sub 1}21, with unit-cell parameters a = b = 116.83, c = 92.24 Å, and contain one protein molecule per asymmetric unit. The V{sub M} value and solvent content are 4.07 Å{sup 3} Da{sup −1} and 69.8%, respectively.

  4. Analysis of Local Rheological Properties of Crystalline Polymer by Dynamic X-ray Diffraction

    Science.gov (United States)

    Nozaki, Shuhei; Kojio, Ken; Takahara, Atsushi; Aoyama, Kohki; Masunaga, Hiroyasu

    Polymer materials form the hierarchical structure from nanometer to micrometer scales. Since the mechanical properties are correlated with the hierarchical structure, the precise evaluation of mechanical properties considering the size of the hierarchical structure is important. Recently, the time-resolved measurement of molecular aggregation structure using microbeam have been carried out diffraction at synchrotron radiation facilities. Analyzing change of crystal structure using microbeam X-ray diffraction under cyclic dynamic strain will give rheological properties of local region of crystalline polymers. In this study, a time-resolved microbeam wide-angle X-ray diffraction was used to study local rheological properties for inside and outside of isotactic polypropylene (iPP) spherulite under cyclic dynamic strain. Local dynamic storage modulus (E) and loss modulus (E\\x9D) were obtained from change of d-spacing in (110) planes of alpha form of iPP crystal for inside and outside of iPP spherulite at a condition with strain of 0.01 and 0.1 Hz. The local E values were larger than those obtained from dynamic viscoelastic property measurement. This might be due to lower modulus of amorphous phase of bulk iPP.

  5. Effect of grain size on stability of X-ray diffraction patterns used for threat detection

    Energy Technology Data Exchange (ETDEWEB)

    Ghammraoui, B., E-mail: bahaa.ghammraoui@cea.fr [CEA-Leti, MINATEC Campus, Recherche Technologique, F-38054 Grenoble (France); Rebuffel, V.; Tabary, J.; Paulus, C.; Verger, L. [CEA-Leti, MINATEC Campus, Recherche Technologique, F-38054 Grenoble (France); Duvauchelle, Ph. [CNDRI-Insa Lyon, Universite de Lyon, F-69621 Villeurbanne Cedex (France)

    2012-08-11

    Energy Dispersive X-ray Diffraction (EDXRD) is well-suited to detecting narcotics and a wide range of explosives. The integrated intensity of an X-ray diffraction peak is proportional to the number of grains in the inspected object which are oriented such that they satisfy Bragg's condition. Several parameters have a significant influence on this number. Among them, we can list grain size and the fill rate for polycrystalline materials that both may significantly vary for a same material according to its way of production. Consequently, peak intensity may change significantly from one measurement to another one, thus increasing the risk of losing peaks. This instability is one of the many causes of false alarms. To help avoid these, we have developed a model to quantify the stability of the diffraction patterns measured. Two methods (extension of the detector in a direction perpendicular to the diffractometer plane and slow rotation of both source and detector) can be used to decrease the coefficient of variation, leading to a more stable spectral measurement.

  6. Analysis of synchrotron X-ray diffraction patterns from fluorotic enamel samples

    Energy Technology Data Exchange (ETDEWEB)

    Almeida, Ana P.G.; Braz, Delson, E-mail: anapaulagalmeida@gmail.co [Coordenacao dos Programas de Pos-graduacao de Engenharia (COPPE/UFRJ), Rio de Janeiro, RJ (Brazil). Lab. de Instrumentacao Nuclear; Colaco, Marcos V.; Barroso, Regina C., E-mail: cely@uerj.b [Universidade do Estado do Rio de Janeiro (UERJ), RJ (Brazil). Inst. de Fisica; Porto, Isabel M., E-mail: belporto@ig.com.b [Universidade Estadual de Campinas (UNICAMP), Piracicaba, SP (Brazil). Faculdade de Odontologia; Gerlach, Raquel F., E-mail: rfgerlach@forp.usp.b [Universidade de Sao Paulo (USP), Ribeirao Preto, SP (Brazil). Faculdade de Odontologia; Droppa Junior, Roosevelt, E-mail: rdroppa@lnls.b [Associacao Brasileira de Tecnologia de Luz Sincrotron (ABTLuS), Campinas, SP (Brazil)

    2009-07-01

    With the introduction of fluoride as the main anticaries agent used in preventive dentistry, and perhaps an increase in fluoride in our food chain, dental fluorosis has become an increasing world-wide problem. Visible signs of fluorosis begin to become obvious on the enamel surface as opacities, implying some porosity in the tissue. The mechanisms that conduct the formation of fluorotic enamel are unknown, but should involve modifications in the basics physical-chemistry reactions of demineralisation and remineralisation of the enamel of the teeth, which is the same reaction of formation of the enamel's hydroxyapatite (HAp) in the maturation phase. The increase of the amount of fluoride inside of the apatite will result in gradual increase of the lattice parameters. The hexagonal symmetry seems to work well with the powder diffraction data, and the crystal structure of HAp is usually described in space group P63/m. The aim of this work is to characterize the healthy and fluorotic enamel in human tooth using technique Synchrotron X-ray diffraction in order to determine the crystal structure and crystallinity of on fluoroapatite (FAp) crystal present in fluoritic enamel. All the scattering profile measurements was carried out at the X-ray diffraction beamline (XRD1) at the National Synchrotron Light Laboratory - LNLS, Campinas, Brazil. (author)

  7. A Spectrometer for X-Ray Energy-Dispersive Diffraction using Synchrotron Radiation

    DEFF Research Database (Denmark)

    Staun Olsen, Janus; Buras, B; Gerward, Leif

    1981-01-01

    Describes a white-beam X-ray energy-dispersive diffractometer built for Hasylab in Hamburg, FRG, using the synchrotron radiation from the electron storage ring DORIS. The following features of the instrument are discussed: horizontal or vertical scattering plane, collimators, sample environment......, remote control of the goniometer, data acquisition, energy-sensitive detectors using small-area and large-area detector crystals, modes of operation, powder and single crystal diffraction. An example is given from a high-pressure study of YbH2 using a diamond anvil cell....

  8. A greedy method for reconstructing polycrystals from three-dimensional X-ray diffraction data

    DEFF Research Database (Denmark)

    Kulshreshth, Arun Kumar; Alpers, Andreas; Herman, Gabor T.

    2009-01-01

    An iterative search method is proposed for obtaining orientation maps inside polycrystals from three-dimensional X-ray diffraction (3DXRD) data. In each step, detector pixel intensities are calculated by a forward model based on the current estimate of the orientation map. The pixel at which...... be achieved by changing the orientation in only a few possible ways. The method selects the location/orientation pair indicated as best by a function that measures data consistency combined with prior information on orientation maps. The superiority of the method to a previously published forward projection...

  9. Determination of Ni(II) crystal structure by powder x-ray diffraction ...

    African Journals Online (AJOL)

    X-ray powder diffraction pattern was used to determine the length of the unit cell, “a”, the lattice structure type, and the number of atoms per unit cell of Ni(II) crystal. The “a” value was determined to be 23.66 ± 0.005 Å, particle size of 34.87 nm, volume 13.24 Å and Strain value ε = 9.8 x 10-3. The cell search on PXRD patterns ...

  10. [Study on bamboo treated with gamma rays by X-ray diffraction].

    Science.gov (United States)

    Sun, Feng-Bo; Fei, Ben-Hua; Jiang, Ze-Hui; Yu, Zi-Xuan; Tian, Gen-Lin; Yang, Quan-Wen

    2011-06-01

    The microfibril angle and crystallinity of bamboo treated with gamma rays were tested by X-ray diffraction (XRD). The result indicated that crystallinity in bamboo increased when irradiation dose was less than 100 kGy, while the irradiation dose was raised to about 100 kGy, crystallinity in bamboo reduced. But during the whole irradiation process, the influence on microfibril angle was not obvious, so it was not the dominant factors on variation in physical-mechanical properties of bamboo during the process of irradiation.

  11. X-ray Diffraction and Neutron Scattering Analysis of Natural and Synthetic Spider Silk Fibers

    Energy Technology Data Exchange (ETDEWEB)

    Lewis, Randolph [Utah State Univ., Logan, UT (United States)

    2013-11-11

    Spider silks have the potential to provide new bio-inspired materials for numerous applications in bioenergetics and products ranging from protective clothing to artificial ligaments and tendons. A number of spider silk genes have been cloned and sequenced by the Lewis laboratory revealing the basis for understanding the key elements of spider silk proteins with respect to their materials performance. In particular, specific amino acid motifs have been identified which have been conserved for over 125 million years in all spiders that use their silk to physically trap prey. The key element in taking the next step toward generating bio-based materials from spider silks will be to move from the current descriptive data to predictive knowledge. Current efforts are focused on mimicking spider silk through synthetic proteins. In developing synthetic silk fibers, we first need to understand the complete secondary and tertiary structure of natural silk so that we can compare synthetic constructs to the natural material. Being able to compare the structure on a single fiber level is critical to the future of molecular directed mimic development because we can vary mechanical properties by different spinning methods. The new generation of synchrotron x-ray diffraction and neutron beamlines will allow, for the first time, determination of the molecular structure of silk fibers and synthetic mimics. We propose an exciting new collaborative research team working jointly between Argonne National Laboratory, Arizona State U. and the University of Wyoming to address the ?characterization of synthetic and natural spider silk fibers using x-ray and neutron diffraction.? Thus these new methodologies will provide understanding of current fibers and determine changes needed to produce fibers with specific properties. The following specific aims are proposed: ? Synthesize spider silk fibers with molecular structures mimicking that of natural silks. Test the mechanic properties of these

  12. Final Report for X-ray Diffraction Sample Preparation Method Development

    Energy Technology Data Exchange (ETDEWEB)

    Ely, T. M.; Meznarich, H. K.; Valero, T.

    2018-01-30

    WRPS-1500790, “X-ray Diffraction Saltcake Sample Preparation Method Development Plan/Procedure,” was originally prepared with the intent of improving the specimen preparation methodology used to generate saltcake specimens suitable for XRD-based solid phase characterization. At the time that this test plan document was originally developed, packed powder in cavity supports with collodion binder was the established XRD specimen preparation method. An alternate specimen preparation method less vulnerable, if not completely invulnerable to preferred orientation effects, was desired as a replacement for the method.

  13. Massive Submandibular Sialolith: Complete Radiographic Registration and Biochemical Analysis through X-Ray Diffraction

    Directory of Open Access Journals (Sweden)

    Ademir Franco

    2014-01-01

    Full Text Available Sialolithiasis is a pathologic condition that affects 60 million people per year, which is caused by the presence of calcified structures, named sialoliths, inside the salivary glands and their salivary ducts. Despite the large incidence of sialolithiasis, its etiology is still unknown. In the present case report, a 47-year-old female patient, presenting with local pain and hampered mouth opening, underwent a surgical approach for the removal of a 20 mm sialolith, which was further analyzed through X-ray diffraction. In parallel, a radiographic registration of 8 years, covering all the period for sialolith formation, is presented along the case report.

  14. In situ X-ray diffraction environments for high-pressure reactions

    DEFF Research Database (Denmark)

    R. S. Hansen, Bjarne; Møller, Kasper Trans; Paskevicius, Mark

    2015-01-01

    New sample environments and techniques specifically designed for in situ powder X-ray diffraction studies up to 1000 bar (1 bar = 105 Pa) gas pressure are reported and discussed. The cells can be utilized for multiple purposes in a range of research fields. Specifically, investigations of gas......–solid reactions and sample handling under inert conditions are undertaken here. Sample containers allowing the introduction of gas from one or both ends are considered, enabling the possibility of flow-through studies. Various containment materials are evaluated, e.g. capillaries of single-crystal sapphire (Al2O3...

  15. Interface structure in directly bonded silicon crystals studied by synchrotron X-ray diffraction

    DEFF Research Database (Denmark)

    Nielsen, Mourits; Feidenhans'l, R.; Howes, P.B.

    1999-01-01

    Fusion-bonded silicon wafers exhibit a superstructure at their common interface due to the spatial beating of the two crystal lattices. The superstructure consists of a network of screw dislocations with a period determined by the twist angle theta. By synchrotron X-ray diffraction, the periodic...... elastic modulation in the two crystals resulting from the dislocation network has been measured. The characteristic thickness of the modulated region is found to be inversely proportional to theta, reaching over 160 Angstrom for theta = 0.4 degrees. This behavior is reproduced in numerical simulations...

  16. Scanning three-dimensional x-ray diffraction microscopy using a high-energy microbeam

    Energy Technology Data Exchange (ETDEWEB)

    Hayashi, Y., E-mail: y-hayashi@mosk.tytlabs.co.jp; Hirose, Y.; Seno, Y. [Toyota Central R& D Toyota Central R& D Labs., Inc., 41-1 Nagakute Aichi 480-1192 Japan (Japan)

    2016-07-27

    A scanning three-dimensional X-ray diffraction (3DXRD) microscope apparatus with a high-energy microbeam was installed at the BL33XU Toyota beamline at SPring-8. The size of the 50 keV beam focused using Kirkpatrick-Baez mirrors was 1.3 μm wide and 1.6 μm high in full width at half maximum. The scanning 3DXRD method was tested for a cold-rolled carbon steel sheet sample. A three-dimensional orientation map with 37 {sup 3} voxels was obtained.

  17. High resolution x-ray and gamma ray imaging using diffraction lenses with mechanically bent crystals

    Science.gov (United States)

    Smither, Robert K [Hinsdale, IL

    2008-12-23

    A method for high spatial resolution imaging of a plurality of sources of x-ray and gamma-ray radiation is provided. High quality mechanically bent diffracting crystals of 0.1 mm radial width are used for focusing the radiation and directing the radiation to an array of detectors which is used for analyzing their addition to collect data as to the location of the source of radiation. A computer is used for converting the data to an image. The invention also provides for the use of a multi-component high resolution detector array and for narrow source and detector apertures.

  18. Sol-Gel Synthesis, X-Ray Diffraction Studies, and Electric Conductivity of Sodium Europium Silicate

    Directory of Open Access Journals (Sweden)

    Ekaterina V. Borisova

    2013-01-01

    Full Text Available Sodium europium silicate, NaEu9(SiO46O2, with apatite structure has been obtained and studied using X-ray diffraction and SEM. It has been shown that sodium sublimation does not take place upon synthesis by the sol-gel method. Rietveld refinement has revealed that sodium atoms are ordered and occupy the 4f position. O(4 atoms not related to silicate ions are placed at the centers of Eu(2 triangles. DC and AC electric conductivity and activation energy have been determined for the compound studied.

  19. Lattice deformation in laser-irradiated silicon crystal studied by picosecond X-ray diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Kishimura, Hiroaki; Yazaki, Akio; Hironaka, Yoichiro; Nakamura, Kazutaka G.; Kondo, Ken-ichi

    2003-02-28

    Lattice deformation in laser-irradiated Si(1 1 1) has been studied by picosecond X-ray diffraction at a delay time of 350 ps. The rapid thermal expansion (0.24% at maximum) was observed at 2.0 GW/cm{sup 2} irradiation. By irradiation above dielectric breakdown threshold (10.0 GW/cm{sup 2}), the intense lattice compression (2.1% at maximum) was observed. The compression is caused by the laser ablation due to dielectric breakdown.

  20. Effects of Fluoride on NiTi Orthodontic Archwires: An X-ray Diffraction Study

    Directory of Open Access Journals (Sweden)

    Sumit Kumar Yadav

    2013-01-01

    Results: Unloading force values of NiTi orthodontic wires were significantly decreased after exposure to both fluoride solutions (p < 0.001. Corrosive changes in surface topography were observed for both fluoride solutions. Wires exposed to acidic fluoride appeared as more severely affected. X-ray diffraction analysis showed no change in crystal lattice of NiTi wires in both solutions. Conclusion: The results suggest that using topical fluoride agents with NiTi wire could decrease the functional unloading mechanical properties of the wire and contribute to prolonged orthodontic treatment.

  1. Characterization of As-Grown Dislocation Structure in Niobium by X-Ray Diffraction Topography.

    Science.gov (United States)

    1981-09-01

    JIOBIUM BY X-RAY DIFFRACTION TOPOGRAPHY, ?’R. Stock, Haydn /Chnand H rn ba urn ONR Contract USNJ0014-75-C-1O12, University of Illinois at Urbana-Champaign...TOPOGRAPHY by S. R. Stock, Haydn Chen and H. K. Bi rnba um Depdrtment Of >’,etd I Iurcy and I’i ni ngE Lng inee ri ng and th. aeral s Resea rch Labo!rdtory...Ty.pe of report and inclusive date*) Technical Report September 1981 S AUTHOR(S) (Last name, first name. initial) Stock, Stuart S., Chen, Haydn and

  2. Internal strains and stresses measured in cortical bone via high-energy x-ray diffraction.

    Energy Technology Data Exchange (ETDEWEB)

    Almer, J. D.; Stock, S. R.; Experimental Facilities Division (APS); Northwestern Univ.,

    2005-01-01

    High-energy synchrotron X-ray diffraction was used to study internal stresses in bone under in situ compressive loading. A transverse cross-section of a 12-14 year old beagle fibula was studied with 80.7 keV radiation, and the transmission geometry was used to quantify internal strains and corresponding stresses in the mineral phase, carbonated hydroxyapatite. The diffraction patterns agreed with tabulated patterns, and the distribution of diffracted intensity around 00.2/00.4 and 22.2 diffraction rings was consistent with the imperfect 00.1 fiber texture expected along the axis of a long bone. Residual compressive stress along the bone's longitudinal axis was observed in the specimen prior to testing: for 22.2 this stress equaled -95 MPa and for 00.2/00.4 was between -160 and -240 MPa. Diffraction patterns were collected for applied compressive stresses up to -110 MPa, and, up to about -100 MPa, internal stresses rose proportionally with applied stress but at a higher rate, corresponding to stress concentration in the mineral of 2.8 times the stress applied. The widths of the 00.2 and 00.4 diffraction peaks indicated that crystallite size perpendicular to the 00.1 planes increased from t = 41 nm before stress was applied to t = 44 nm at -118 MPa applied stress and that rms strain {var_epsilon}{sub rms} rose from 2200 {mu}{var_epsilon} before loading to 4600 {mu}{var_epsilon} at the maximum applied stress. Small angle X-ray scattering of the unloaded sample, recorded after deformation was complete, showed a collagen D-period of 66.4 nm (along the bone axis).

  3. Characteristics of a molybdenum X-pinch X-ray source as a probe source for X-ray diffraction studies

    Science.gov (United States)

    Zucchini, F.; Bland, S. N.; Chauvin, C.; Combes, P.; Sol, D.; Loyen, A.; Roques, B.; Grunenwald, J.

    2015-03-01

    X-ray emission from a molybdenum X-pinch has been investigated as a potential probe for the high pressure states made in dynamic compression experiments. Studies were performed on a novel 300 kA, 400 ns generator which coupled the load directly to a low inductance capacitor and switch combination. The X-pinch load consisted of 4 crossed molybdenum wires of 13 μm diameter, crossed at an angle of 62°. The load height was 10 mm. An initial x-ray burst generated at the wire crossing point, radiated in the soft x-ray range (hυ x-ray burst (hυ > 10 keV) whose power ranged from 1 to 7 MW. Time integrated spectral measurements showed that the harder bursts were dominated by K-alpha emission; though, a lower level, wide band continuum up to at least 30 keV was also present. Initial tests demonstrated that the source was capable of driving Laue diffraction experiments, probing uncompressed samples of LiF and aluminium.

  4. Structural analysis of lead magnesium niobate using synchrotron powder X-ray diffraction and the Rietveld method.

    Science.gov (United States)

    Bhakar, Ashok; Pandey, Adityanarayan H; Singh, M N; Upadhyay, Anuj; Sinha, A K; Gupta, S M; Ganguli, Tapas

    2016-06-01

    The room-temperature synchrotron powder X-ray diffraction pattern of the single phase perovskite lead magnesium niobate (PMN) has shown significant broadening in the q range ∼ 5-7 Å(-1) compared with standard LaB6 synchrotron powder X-ray diffraction data, taken under similar conditions. This broadening/asymmetry lies mainly towards the lower 2θ side of the Bragg peaks. Attempts to fit this data with the paraelectric cubic phase (Pm\\bar 3m) and the local rhombohedral phase (R3m) corresponding to polar nanoregions (PNRs) are made using the Rietveld method. Rietveld refinements show that neither cubic (Pm\\bar 3m) nor rhombohedral (R3m) symmetry can fit this XRD pattern satisfactorily. The two-phase refinement fits the experimental data satisfactorily and suggests that the weight percentage of the PNRs is approximately 12-16% at room temperature. The unit-cell volume of these rhombohedral PNRs is approximately 0.15% larger than that of the unit cell volume of the paraelectric cubic phase.

  5. Non-conventional applications of a noninvasive portable X-ray diffraction/fluorescence instrument

    Energy Technology Data Exchange (ETDEWEB)

    Chiari, Giacomo [Getty Conservation Institute, Science Department, Los Angeles, CA (United States); Sarrazin, Philippe [Examinart LLC, Sunnyvale, CA (United States); Heginbotham, Arlen [The J. Paul Getty Museum, Sculpture and Decorative Arts Conservation, Los Angeles, CA (United States)

    2016-11-15

    Noninvasive techniques have become widespread in the cultural heritage analytical domain. The popular handheld X-ray fluorescence (XRF) devices give the elemental composition of all the layers that X-rays can penetrate, but no information on how atoms are bound together or at which depth they are located. A noninvasive portable X-ray powder diffraction/X-ray fluorescence (XRD/XRF) device may offer a solution to these limitations, since it can provide information on the composition of crystalline materials. This paper introduces applications of XRD beyond simple phase recognition. The two fundamental principles for XRD are: (1) the crystallites should be randomly oriented, to ensure proper intensity to all the diffraction peaks, and (2) the material should be positioned exactly in the focal plane of the instrument, respecting its geometry, as any displacement of the sample would results in 2θ shifts of the diffraction peaks. In conventional XRD, the sample is ground and set on the properly positioned sample holder. Using a noninvasive portable instrument, these two requirements are seldom fulfilled. The position, size and orientation of a given crystallite within a layered structure depend on the object itself. Equation correlating the displacement (distance from the focal plane) versus peak shift (angular difference in 2θ from the standard value) is derived and used to determine the depth at which a given substance is located. The quantitative composition of two binary Cu/Zn alloys, simultaneously present, was determined measuring the cell volume and using Vegard's law. The analysis of the whole object gives information on the texture and possible preferred orientations of the crystallites, which influences the peak intensity. This allows for the distinction between clad and electroplated daguerreotypes in the case of silver and between ancient and modern gilding for gold. Analyses of cross sections can be carried out successfully. Finally, beeswax, used in

  6. Non-conventional applications of a noninvasive portable X-ray diffraction/fluorescence instrument

    Science.gov (United States)

    Chiari, Giacomo; Sarrazin, Philippe; Heginbotham, Arlen

    2016-11-01

    Noninvasive techniques have become widespread in the cultural heritage analytical domain. The popular handheld X-ray fluorescence (XRF) devices give the elemental composition of all the layers that X-rays can penetrate, but no information on how atoms are bound together or at which depth they are located. A noninvasive portable X-ray powder diffraction/X-ray fluorescence (XRD/XRF) device may offer a solution to these limitations, since it can provide information on the composition of crystalline materials. This paper introduces applications of XRD beyond simple phase recognition. The two fundamental principles for XRD are: (1) the crystallites should be randomly oriented, to ensure proper intensity to all the diffraction peaks, and (2) the material should be positioned exactly in the focal plane of the instrument, respecting its geometry, as any displacement of the sample would results in 2 θ shifts of the diffraction peaks. In conventional XRD, the sample is ground and set on the properly positioned sample holder. Using a noninvasive portable instrument, these two requirements are seldom fulfilled. The position, size and orientation of a given crystallite within a layered structure depend on the object itself. Equation correlating the displacement (distance from the focal plane) versus peak shift (angular difference in 2 θ from the standard value) is derived and used to determine the depth at which a given substance is located. The quantitative composition of two binary Cu/Zn alloys, simultaneously present, was determined measuring the cell volume and using Vegard's law. The analysis of the whole object gives information on the texture and possible preferred orientations of the crystallites, which influences the peak intensity. This allows for the distinction between clad and electroplated daguerreotypes in the case of silver and between ancient and modern gilding for gold. Analyses of cross sections can be carried out successfully. Finally, beeswax, used in

  7. Probing deformation substructure by synchrotron X-ray diffraction and dislocation dynamics modelling.

    Science.gov (United States)

    Korsunsky, Alexander M; Hofmann, Felix; Song, Xu; Eve, Sophie; Collins, Steve P

    2010-09-01

    Materials characterization at the nano-scale is motivated by the desire to resolve the structural aspects and deformation behavior at length scales relevant to those mechanisms that define the novel and unusual properties of nano-structured materials. A range of novel techniques has recently become accessible with the help of synchrotron X-ray beams that can be focused down to spot sizes of less than a few microns on the sample. The unique combination of tunability (energy selection), parallelism and brightness of synchrotron X-ray beams allows their use for high resolution diffraction (determination of crystal structure and transformations, analysis of dislocation sub-structures, orientation and texture analysis, strain mapping); small angle X-ray scattering (analysis of nano-scale voids and defects; orientation analysis) and imaging (radiography and tomography). After a brief review of the state-of-the-art capabilities for monochromatic and white beam synchrotron diffraction, we consider the usefulness of these techniques for the task of bridging the gap between experiment and modeling. Namely, we discuss how the experiments can be configured to provide information relevant to the validation and improvement of modeling approaches, and also how the results of various simulations can be post-processed to improve the possibility of (more or less) direct comparison with experiments. Using the example of some recent experiments carried out on beamline 116 at Diamond Light Source near Oxford, we discuss how such experimental results can be interpreted in view and in conjunction with numerical deformation models, particularly those incorporating dislocation effects, e.g., finite-element based pseudo-continuum strain gradient formulations, and discrete dislocation simulations. Post-processing of FE and discrete dislocation simulations is described, illustrating the kind of information that can be extracted from comparisons between modeling and experimental data.

  8. Characterization of nanowires by coherent X-ray diffractive imaging and ptychography

    Energy Technology Data Exchange (ETDEWEB)

    Dzhigaev, Dmitry

    2017-03-15

    Imaging techniques are of paramount importance for our understanding of the universe. From galaxies and stars explored by huge telescopes down to micro and nanostructures studied by microscopes, imaging systems provide invaluable scientific information. When an object under investigation has a size of about 100 nanometers, X-rays become a perfect probe for non-destructive imaging. The manufacturing process of image forming lenses for X-rays becomes much more complicated comparing to optical ones. Therefore, ''lensless'' techniques which rely on the coherent properties of radiation were developed. With third generation of synchrotron sources highly coherent and intense X-ray beams became widely accessible. They are used in new imaging methods such as coherent X-ray diffractive imaging (CXDI) and X-ray ptychography. Modern nanotechnology opens a wide spectrum of possible applications in different branches of physics, chemistry, biology and engineering. At the nanoscale, matter has different physical and chemical properties compared to the macroscale bulk material. The continuing trend of miniaturization of functional components in semiconductor industry brings new challenges both in growth and characterization methods. This Thesis is focused on application of coherent diffractive imaging methods to reveal the structure of single semiconductor nanowires (NWs). They have been attracting significant attention for a couple of decades due to their efficient strain relaxation properties. And since the strain plays a significant role in NW performance the projects carried out in this work are oriented on Bragg CXDI approaches. Three distinct projects were carried out during my research activity at DESY research center of the Helmholtz Association. Experimental work was performed at P06 and P10 beamlines at PETRA III synchrotron. The first part of this Thesis extends the application of the three-dimensional (3D) Bragg CXDI to strain field mapping in a

  9. Real-time observation of X-ray diffraction patterns with the Lixiscope

    Science.gov (United States)

    Chung, D. Y.; Tsang, T.; Yin, L. I.; Anderson, J. R.

    1981-01-01

    The feasibility of the Lixiscope (Low Intensity X-ray Imaging Scope) is demonstrated for real-time observation of transmission Laue patterns. Making use of the high-gain capability of microchannel plate (MCP) visible-light image intensifier tubes, X-ray images are converted to visible-light images by a scintillator. Pb discs are taped to the center of the Lixiscope input face, and crystal samples are held on a goniometer stage with modeling clay. With a compact size to facilitate off axis viewing, and real-time viewing to allow instantaneous response, the Lixiscope may prove useful in dynamic studies of the effects of plastic flows, stresses, high pressures, and low temperatures.

  10. Time-Resolved Soft X-ray Diffraction Reveals Transient Structural Distortions of Ternary Liquid Crystals

    Directory of Open Access Journals (Sweden)

    Klaus Mann

    2009-11-01

    Full Text Available Home-based soft X-ray time-resolved scattering experiments with nanosecond time resolution (10 ns and nanometer spatial resolution were carried out at a table top soft X-ray plasma source (2.2–5.2 nm. The investigated system was the lyotropic liquid crystal C16E7/paraffin/glycerol/formamide/IR 5. Usually, major changes in physical, chemical, and/or optical properties of the sample occur as a result of structural changes and shrinking morphology. Here, these effects occur as a consequence of the energy absorption in the sample upon optical laser excitation in the IR regime. The liquid crystal shows changes in the structural response within few hundred nanoseconds showing a time decay of 182 ns. A decrease of the Bragg peak diffracted intensity of 30% and a coherent macroscopic movement of the Bragg reflection are found as a response to the optical pump. The Bragg reflection movement is established to be isotropic and diffusion controlled (1 μs. Structural processes are analyzed in the Patterson analysis framework of the time-varying diffraction peaks revealing that the inter-lamellar distance increases by 2.7 Å resulting in an elongation of the coherently expanding lamella crystallite. The present studies emphasize the possibility of applying TR-SXRD techniques for studying the mechanical dynamics of nanosystems.

  11. X-Ray Diffraction Phase Analyses for Granulated and Sintered Ceramic Materials

    Directory of Open Access Journals (Sweden)

    Suminar Pratapa

    2007-11-01

    Full Text Available One basic problematic aspect in x-ray diffraction phase analysis is microabsorption effect which may arise from the size of the crystallite phases. Complication of the problem may intensify in sintered ceramic materials where milling of the samples is not simple. We report the Rietveld x-ray diffraction phase analysis of MgO-α-Al2O3 powder mixtures with phase content ratio of 1:1 by weight and MgO-Y2O3 sintered ceramic composites with Y2O3 contents of 10%, 20% and 30% by weight. The mixtures were pre-sintered at 1000°C for 2 hours and then milled while the composites were sintered at 1550°C for 3 hours. The phase composition analysis was done using Rietica, a non-commercial Rietveld method-based software. Relative and absolute phase compositions were examined and results showed that there was a significant amount of phase composition bias resulted from the examination. For the powder mixture, milling can reduce microabsorption effect and hence the calculation bias. For the ceramic composite where milling is almost impossible, additional of Y2O3 caused smaller crystallite size of MgO, so that composition bias is smaller in composites with higher Y2O3 content. A mathematical model is proposed to provide more acceptable phase composition results.

  12. Crystallization and preliminary X-ray diffraction analysis of recombinant hepatitis E virus-like particle

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Che-Yen [Molecular and Cellular Biology, University of California, Davis, CA 95616 (United States); Karolinska Institute Structural Virology, F68 Karolinska University Hospital, SE-14186 Stockholm (Sweden); Institute of Public Health, National Yang-Ming University, 112 Taipei,Taiwan (China); Miyazaki, Naoyuki [Molecular and Cellular Biology, University of California, Davis, CA 95616 (United States); Karolinska Institute Structural Virology, F68 Karolinska University Hospital, SE-14186 Stockholm (Sweden); Institute for Protein Research, Osaka University, 3-2 Yamadaoka, Suita, Osaka 565-0871 (Japan); Yamashita, Tetsuo [Institute for Protein Research, Osaka University, 3-2 Yamadaoka, Suita, Osaka 565-0871 (Japan); Institute for Microbial Diseases, Osaka University, 3-2 Yamadaoka, Suita, Osaka 565-0871 (Japan); Higashiura, Akifumi; Nakagawa, Atsushi [Institute for Protein Research, Osaka University, 3-2 Yamadaoka, Suita, Osaka 565-0871 (Japan); Li, Tian-Cheng; Takeda, Naokazu [Department of Virology II, National Institute of Infectious Diseases, Tokyo (Japan); Xing, Li [Molecular and Cellular Biology, University of California, Davis, CA 95616 (United States); Karolinska Institute Structural Virology, F68 Karolinska University Hospital, SE-14186 Stockholm (Sweden); Hjalmarsson, Erik; Friberg, Claes [Crystal Research AB, 22370 Lund (Sweden); Liou, Der-Ming [Institute of Public Health, National Yang-Ming University, 112 Taipei,Taiwan (China); Sung, Yen-Jen [Institute of Public Health, National Yang-Ming University, 112 Taipei,Taiwan (China); Institute of Anatomy and Cell Biology, National Yang-Ming University, 112 Taipei,Taiwan (China); Tsukihara, Tomitake [Institute for Protein Research, Osaka University, 3-2 Yamadaoka, Suita, Osaka 565-0871 (Japan); Matsuura, Yoshiharu [Institute for Microbial Diseases, Osaka University, 3-2 Yamadaoka, Suita, Osaka 565-0871 (Japan); Miyamura, Tatsuo [Department of Virology II, National Institute of Infectious Diseases, Tokyo (Japan); Cheng, R. Holland, E-mail: rhch@ucdavis.edu [Molecular and Cellular Biology, University of California, Davis, CA 95616 (United States); Karolinska Institute Structural Virology, F68 Karolinska University Hospital, SE-14186 Stockholm (Sweden)

    2008-04-01

    A recombinant virus-like particle that is a potential oral hepatitis E vaccine was crystallized. Diffraction data were collected to 8.3 Å resolution and the X-ray structure was phased with the aid of a low-resolution density map determined using cryo-electron microscopy data. Hepatitis E virus (HEV) accounts for the majority of enterically transmitted hepatitis infections worldwide. Currently, there is no specific treatment for or vaccine against HEV. The major structural protein is derived from open reading frame (ORF) 2 of the viral genome. A potential oral vaccine is provided by the virus-like particles formed by a protein construct of partial ORF3 protein (residue 70–123) fused to the N-terminus of the ORF2 protein (residues 112–608). Single crystals obtained by the hanging-drop vapour-diffusion method at 293 K diffract X-rays to 8.3 Å resolution. The crystals belong to space group P2{sub 1}2{sub 1}2{sub 1}, with unit-cell parameters a = 337, b = 343, c = 346 Å, α = β = γ = 90°, and contain one particle per asymmetric unit.

  13. Three-dimensional coherent X-ray diffractive imaging of whole frozen-hydrated cells

    Directory of Open Access Journals (Sweden)

    Jose A. Rodriguez

    2015-09-01

    Full Text Available A structural understanding of whole cells in three dimensions at high spatial resolution remains a significant challenge and, in the case of X-rays, has been limited by radiation damage. By alleviating this limitation, cryogenic coherent diffractive imaging (cryo-CDI can in principle be used to bridge the important resolution gap between optical and electron microscopy in bio-imaging. Here, the first experimental demonstration of cryo-CDI for quantitative three-dimensional imaging of whole frozen-hydrated cells using 8 keV X-rays is reported. As a proof of principle, a tilt series of 72 diffraction patterns was collected from a frozen-hydrated Neospora caninum cell and the three-dimensional mass density of the cell was reconstructed and quantified based on its natural contrast. This three-dimensional reconstruction reveals the surface and internal morphology of the cell, including its complex polarized sub-cellular structure. It is believed that this work represents an experimental milestone towards routine quantitative three-dimensional imaging of whole cells in their natural state with spatial resolutions in the tens of nanometres.

  14. Crystallization and preliminary X-ray diffraction study of phosphoribosyl pyrophosphate synthetase from E. Coli

    Energy Technology Data Exchange (ETDEWEB)

    Timofeev, V. I., E-mail: inna@ns.crys.ras.ru; Abramchik, Yu. A., E-mail: tostars@mail.ru; Zhukhlistova, N. E., E-mail: ugama@yandex.ru; Kuranova, I. P. [Russian Academy of Sciences, Shubnikov Institute of Crystallography (Russian Federation)

    2015-09-15

    Enzymes of the phosphoribosyl pyrophosphate synthetase family (PRPPS, EC 2.7.6.1) catalyze the formation of 5-phosphoribosyl pyrophosphate (5-PRPP) from adenosine triphosphate and ribose 5-phosphate. 5-Phosphoribosyl pyrophosphate is an important intermediate in the synthesis of purine, pyrimidine, and pyridine nucleotides, as well as of the amino acids histidine and tryptophan. The crystallization conditions for E. coli PRPPS were found by the vapor-diffusion technique and were optimized to apply the capillary counter-diffusion technique. The X-ray diffraction data set was collected from the crystals grown by the counter-diffusion technique using a synchrotron radiation source to 3.1-Å resolution. The crystals of PRPPS belong to sp. gr. P6{sub 3}22 and have the following unit-cell parameters: a = b = 104.44 Å, c = 124.98 Å, α = β = 90°, γ = 120°. The collected X-ray diffraction data set is suitable for the solution of the three-dimensional structure of PRPPS at 3.1-Å resolution.

  15. High energy white beam x-ray diffraction studies of residual strains in engineering components

    Science.gov (United States)

    Zhang, S. Y.; Vorster, W.; Jun, T. S.; Song, X.; Golshan, M.; Laundy, D.; Walsh, M. J.; Korsunsky, A. M.

    2008-09-01

    In order to predict the durability of engineering components and improve performance, it is mandatory to understand residual stresses. The last decade has witnessed a significant increase of residual stress evaluation using diffraction of penetrating radiation, such as neutrons or high energy X-rays. They provide a powerful non-destructive method for determining the level of residual stresses in engineering components through precise characterisation of interplanar crystal lattice spacing. The unique non-destructive nature of these measurement techniques is particularly beneficial in the context of engineering design, since it allows the evaluation of a variety of structural and deformational parameters inside real components without material removal, or at worst with minimal interference. However, while most real engineering components have complex shape and are often large in size, leading to measurement and interpretation difficulties, since experimental facilities usually have limited space for mounting the sample, limited sample travel range, limited loading capacity of the sample positioning system, etc. Consequently, samples often have to be sectioned, requiring appropriate corrections on measured data; or facilities must be improved. Our research group has contributed to the development of engineering applications of high-energy X-ray diffraction methods for residual stress evaluation, both at synchrotron sources and in the lab setting, including multiple detector setup, large engineering component manipulation and measurement at the UK Synchrotron Radiation Source (SRS Daresbury), and in our lab at Oxford. A nickel base superalloy combustion casing and a large MIG welded Al alloy plate were successfully studied.

  16. Which orbital and charge ordering in transition metal oxides can resonant X-ray diffraction detect?

    Energy Technology Data Exchange (ETDEWEB)

    Di Matteo, Sergio, E-mail: sergio.dimatteo@univ-rennes1.f [Equipe de Physique des Surfaces et Interfaces, Institut de Physique de Rennes UMR UR1-CNRS 6251, Universite de Rennes 1, F-35042 Rennes Cedex (France)

    2009-11-15

    The present article is a brief critical review about the possibility of detecting charge and/or orbital order in transition-metal oxides by means of resonant x-ray diffraction. Many recent models of transition-metal oxides are based on charge and/or orbitally ordered ground-states and it has been claimed in the past that resonant x-ray diffraction is able to confirm or reject them. However, in spite of the many merits of this technique, such claims are ambiguous, because the interpretative frameworks used to analyze such results in transition-metal oxides, where structural distortions are always associated to the claimed charged/orbitally ordered transition, strongly influence (not to say suggest) the answer. In order to clarify this point, I discuss the two different definitions of orbital and charge orderings which are often used in the literature without a clear distinction. My conclusion is that the answer to the question of the title depends on which definition is adopted.

  17. Characterization of the Roraima savanna across of X-ray diffraction, thermomagnetic analysis and Moessbauer spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Gilmar A.; Araujo, R.C.; Sergio, C.S. [Universidade Federal de Roraima (UFRR), Boa Vista, RR (Brazil)

    2012-07-01

    Full text: The technique of X-ray diffraction has great resolving power to determine the phases present in crystalline material, thereby enabling it to determine the elements present in the materials as well as changes in structure that they can suffer when subjected to various physical processes and/or chemical means. The research had as objective to characterize the mineralogy of iron oxides, silicon, aluminum and other minerals in the soil of five points of the Roraima savannah. The points where samples were collected are five municipalities in the state of Roraima. The area of sampling is part of the savanna in Roraima. The samples were collected. We analyzed samples from five points from the collection of natural soil in the locations listed. The samples were placed in a mill to a uniform grain size. After the milling process, the magnetic material was separated using a permanent magnet. Then the samples were analyzed by x-ray diffraction, thermomagnetic analysis and Moessbauer spectroscopy. Preliminary results of XRD showed the occurrence of phases of oxides of iron, silicon, aluminum and other phases less. Thermomagnetic analysis show that the magnetic phases are magnetite and hematite. The results of the Moessbauer spectroscopy indicates the reliability in the two prior art and confirmed the presence of the phases of oxides of iron present in the soil analyzed. (author)

  18. Development of an ultra-high resolution diffraction grating forsoft x-rays

    Energy Technology Data Exchange (ETDEWEB)

    Voronov, Dmitriy L.; Cambie, Rossana; Feshchenko, Ruslan M.; Gullikson, Eric M.; Padmore, Howard A.; Vinogradov, Alexander V.; Yashchuk, Valeriy V.

    2007-08-21

    Resonant Inelastic X-ray Scattering (RIXS) is the one of themost powerful methods for investigation of the electronic structure ofmaterials, specifically of excitations in correlated electron systems.However the potential of the RIXS technique has not been fully exploitedbecause conventional grating spectrometers have not been capable ofachieving the extreme resolving powers that RIXS can utilize. State ofthe art spectrometers in the soft x-ray energy range achieve ~;0.25 eVresolution, compared to the energy scales of soft excitations andsuperconducting gap openings down to a few meV. Development ofdiffraction gratings with super high resolving power is necessary tosolve this problem. In this paper we study the possibilities offabrication of gratings of resolving power of up to 106 for the 0.5 1.5KeV energy range. This energy range corresponds to all or most of theuseful dipole transitions for elements of interest in most correlatedelectronic systems, i.e., oxygen K-edge of relevance to all oxides, thetransition metal L2,3 edges, and the M4,5 edges of the rare earths.Various approaches based on different kinds of diffraction gratings suchas deep-etched multilayer gratings, and multilayer coated echelettes arediscussed. We also present simulations of diffraction efficiency for suchgratings, and investigate the necessary fabricationtolerances.

  19. Ultrasonic acoustic levitation for fast frame rate X-ray protein crystallography at room temperature

    National Research Council Canada - National Science Library

    Tsujino, Soichiro; Tomizaki, Takashi

    2016-01-01

    ... of biomolecules and structure-based drug developments. Using lysozyme model crystals, we demonstrated the rapid acquisition of X-ray diffraction datasets by combining a high frame rate pixel array detector with ultrasonic acoustic levitation of protein...

  20. Phase transformations in thermally cycled Cu/ZrW2O8 composites investigated by synchrotron x-ray diffraction

    Science.gov (United States)

    Yilmaz, S.

    2002-01-01

    A Cu/ZrW2O8 metal matrix composite was thermally cycled between 298 and 591 K while being subjected to x-ray diffraction in transmission using high-intensity synchrotron radiation. The reversible allotropic phase transformations of ZrW2O8 between its two low-pressure phases and its high-pressure phase were observed within the composite bulk as a function of temperature. This observation gives experimental proof of the existence of the reversible pressure-induced phase transformation, which had been inferred indirectly from dilatometry in a previous investigation and assigned to the large thermal mismatch stresses in the composite. The volume fraction of each ZrW2O8 compound was determined from the measured diffracted intensity, and the thermal expansion behaviour of the composite was then calculated. Good agreement was found with the experimental dilatometric curve reported in a recent investigation.

  1. Neutron and high-pressure X-ray diffraction study of hydrogen-bonded ferroelectric rubidium hydrogen sulfate.

    Science.gov (United States)

    Binns, Jack; McIntyre, Garry J; Parsons, Simon

    2016-12-01

    The pressure- and temperature-dependent phase transitions in the ferroelectric material rubidium hydrogen sulfate (RbHSO4) are investigated by a combination of neutron Laue diffraction and high-pressure X-ray diffraction. The observation of disordered O-atom positions in the hydrogen sulfate anions is in agreement with previous spectroscopic measurements in the literature. Contrary to the mechanism observed in other hydrogen-bonded ferroelectric materials, H-atom positions are well defined and ordered in the paraelectric phase. Under applied pressure RbHSO4 undergoes a ferroelectric transition before transforming to a third, high-pressure phase. The symmetry of this phase is revised to the centrosymmetric space group P21/c, resulting in the suppression of ferroelectricity at high pressure.

  2. Crystallization and preliminary X-ray diffraction studies of arginase from a thermophilic organism Bacillus caldevelox.

    Science.gov (United States)

    Smith, C A; Pratchett, M L; Baker, E N

    1995-09-01

    A thermostable hexameric arginase purified from the extreme thermophile Bacillus caldevelox has been crystallized from Hepes buffer at pH 7.5 in the presence of 12% polyethylene glycol 4000 and 10% 2-propanol, and from cacodylate buffer at pH 7.2 in the presence of 15% 2-propanol and sodium citrate. The latter crystals are more suitable for X-ray diffraction analysis. The crystals are in the orthorhombic space group P2(1)2(1)2(1) with unit-cell dimensions a = 156.3, b = 148.0 and c = 85.4 A. The asymmetric unit contains one hexamer (approximate molecular mass 183 kDa) and has a solvent content of approximately 54%. The crystals diffract to 2.8 A resolution.

  3. On the microstructure of nanoporous gold: an X-ray diffraction study.

    Science.gov (United States)

    Van Petegem, Steven; Brandstetter, Stefan; Hodge, Andrea M; El-Dasher, Bassem S; Biener, Jurgen; Schmitt, Bernd; Borca, Camelia; Van Swygenhoven, Helena

    2009-03-01

    The evolution of the grain structure, internal strain, and the lattice misorientations of nanoporous gold during dealloying of bulk (3D) Ag-Au alloy samples was studied by various in situ and ex situ X-ray diffraction techniques including powder and Laue diffraction. The experiments reveal that the dealloying process preserves the original crystallographic structure but leads to a small spread in orientations within individual grains. Initially, most grains develop in-plane tensile stresses, which are partly released during further dealloying. Simultaneously, the feature size of the developing nanoporous structure increases with increasing dealloying time. Finally, microdiffraction experiments on dealloyed micron-sized nanoporous pillars reveal significant surface damage introduced by focused ion beam milling.

  4. Three-beam resonant X-ray diffraction in germanium - Laue transmission cases.

    Science.gov (United States)

    Thorkildsen, Gunnar; Larsen, Helge B; Weckert, Edgar; Mo, Frode; Mathiesen, Ragnvald H

    2005-07-01

    Perturbation of the two-beam diffracted power owing to the influence of a third lattice node has been examined for various three-beam cases in a small finite germanium crystal in the vicinity of the K-absorption edge. Although the crystal was slightly imperfect, the main parts of the experimental results are very well described within the framework of the fundamental theory of X-ray diffraction in conjunction with Cromer-Liberman calculations for the resonant scattering terms. Beam divergence and dynamical block size are treated as adjustable parameters in the analysis. Observed changes in the three-beam profile asymmetry are mainly attributed to size and not to resonance effects associated with the triplet phase sum of the involved reflections. Close to the absorption edge there is however some evidence indicating that f' values should be reduced in magnitude compared to the tabulated ones.

  5. Microscopic stress characterisation of functional iron-based alloys by white X-ray microbeam diffraction

    Science.gov (United States)

    Kwon, E. P.; Sato, S.; Fujieda, S.; Shinoda, K.; Kajiwara, K.; Sato, M.; Suzuki, S.

    2018-01-01

    Microscopic residual stress evolution in an austenite (γ) grain during a shape-memory process in an Fe-Mn-Si-Cr alloy was investigated using the white X-ray microbeam diffraction technique. The stresses were measured on a coarse grain, which had an orientation near , parallel to the tensile loading direction with a high Schmid factor for a martensitic transformation. The magnitude of the residual stresses in a grain of the sample, which was subjected to a 23 % tensile strain and subsequent shape-recovery heating, was found to be very small and comparable to that prior to tensile deformation. Measurements of the recovery strain and microstructural analyses using electron backscatter diffraction suggested that the low residual stresses could be attributed to the significant shape recovery caused by a highly reversible martensitic transformation in the grain with a particular orientation.

  6. Synchrotron X-ray diffraction analysis of epitaxial GaN layer laterally overgrown

    CERN Document Server

    Feng Gan; Wang Yu Tian; Yang Hui; Liang Jun Wu; Zheng Wen Li; Jia Quan Jie

    2002-01-01

    The GaN layer grown by epitaxial lateral overgrowth on sapphire (0001) has been investigated by synchrotron X-ray diffraction. The results show that ELO GaN stripes bend towards the SiN sub x mask in directions perpendicular to the stripe direction. This lead to the GaN (0001) crystal planes in the 'wings' (overgrown GaN) exhibit crystallographic tilts away from those in the 'window' (seed) regions. The GaN (0002) diffraction was used to determine the grain sizes in the wing region and window region, respectively. It is found that the grain size in the wing region increases about three times comparing to those in window region

  7. High-efficiency diffractive x-ray optics from sectioned multilayers

    Energy Technology Data Exchange (ETDEWEB)

    Kang, H C; Stephenson, G B; Liu, C; Conley, R; Macrander, A T; Maser, J; Bajt, S; Chapman, H N

    2004-12-14

    We investigate the diffraction properties of sectioned multilayers in Laue (transmission) geometry, at hard x-ray energies (9.5 and 19.5 keV). Two samples are studied, a 200 period W/Si multilayer of 29 nm d-spacing, and a 2020 period Mo/Si multilayer of 7 nm d-spacing, with cross-section depths ranging from 2 to 17 {micro}m. Rocking curves across the Bragg reflections exhibit well-defined interference fringes originating from the depth of the sample. Efficiencies as high as 70% were obtained. This exceeds the theoretical limit for standard zone plates operating in the multi-beam regime, demonstrating that all of the intensity can be directed into a single diffraction order in small-period structures.

  8. X-ray diffraction patterns and diffracted intensity of Kα spectral lines of He-like ions

    Science.gov (United States)

    Goyal, Arun; Khatri, Indu; Singh, A. K.; Sharma, Rinku; Mohan, Man

    2017-09-01

    In the present paper, we have calculated fine-structure energy levels related to the configurations 1s2s, 1s2p, 1s3s and 1s3p by employing GRASP2K code. We have also computed radiative data for transitions from 1s2p 1 P1o, 1s2p 3 P2o, 1s2p 3 P1o and 1s2s 3S1 to the ground state 1s2. We have made comparisons of our presented energy levels and transition wavelengths with available results compiled by NIST and good agreement is achieved. We have also provided X-ray diffraction (XRD) patterns of Kα spectral lines, namely w, x, y and z of Cu XXVIII, Kr XXXV and Mo with diffraction angle and maximum diffracted intensity which is not published elsewhere in the literature. We believe that our presented results may be beneficial in determination of the order parameter, X-ray crystallography, solid-state drug analysis, forensic science, geological and medical applications.

  9. Study of the crystallization kinetics of LAS glass by differential scanning calorimetry, X-ray diffraction, and beam bending viscometry

    Energy Technology Data Exchange (ETDEWEB)

    Ovono Ovono, D.; Berre, S.; Pradeau, P.; Comte, M. [Corning SAS, Corning European Technology Center, 7 bis, avenue de Valvins, 77210 Avon (France); Bruno, G., E-mail: brunog@corning.com [Corning SAS, Corning European Technology Center, 7 bis, avenue de Valvins, 77210 Avon (France)

    2012-01-10

    Highlights: Black-Right-Pointing-Pointer The crystallization of LAS glass was investigated using XRD, DSC and beam bending viscometry. Black-Right-Pointing-Pointer Different models were used to determine the kinetic parameters for crystallization. Black-Right-Pointing-Pointer The activation energy and Avrami parameters obtained are consistent with reported values. Black-Right-Pointing-Pointer The crystallization of LAS glass occurs with three-dimensional crystals growth. - Abstract: The crystallization kinetics of a commercial lithium-aluminum silicate (LAS) glass were characterized by differential scanning calorimetry (DSC) under non-isothermal conditions, by in-situ X-ray diffraction, and by three point beam bending viscosimeter (BBV). Non-isothermal DSC experiments were conducted at different heating rates. Results show that the crystal growth is controlled by a thermally activated process of the Arrhenius type. The activation energies obtained from isoconversional analysis are close to that extracted using the Johnson-Mehl-Avrami equation. While X-ray diffraction volume fraction data confirm the DSC analysis, it also shows that the crystallite size changes only at the end of the heat treatment protocol, during a hold at temperatures as high as 1000 Degree-Sign C. In this latter case, the crystal growth follows the Ostwald ripening mechanism. Finally, the viscosity measured in the crystallization region by BBV provides the activation energy for viscous flow, and it is slightly higher than the values obtained by DSC.

  10. Characterization of Japanese color sticks by energy dispersive X-ray fluorescence, X-ray diffraction and Fourier transform infrared analysis

    Science.gov (United States)

    Manso, M.; Valadas, S.; Pessanha, S.; Guilherme, A.; Queralt, I.; Candeias, A. E.; Carvalho, M. L.

    2010-04-01

    This work comprises the use of energy dispersive X-ray fluorescence (EDXRF), X-ray diffraction (XRD) and Fourier transformed infrared (FTIR) techniques for the study of the composition of twentieth century traditional Japanese color sticks. By using the combination of analytical techniques it was possible to obtain information on inorganic and organic pigments, binders and fillers present in the sticks. The colorant materials identified in the sticks were zinc and titanium white, chrome yellow, yellow and red ochre, vermillion, alizarin, indigo, Prussian and synthetic ultramarine blue. The results also showed that calcite and barite were used as inorganic mineral fillers while Arabic gum was the medium used. EDXRF offered great potential for such investigations since it allowed the identification of the elements present in the sample preserving its integrity. However, this information alone was not enough to clearly identify some of the materials in study and therefore it was necessary to use XRD and FTIR techniques.

  11. Combination of Raman, infrared, and X-ray energy-dispersion spectroscopies and X-ray d diffraction to study a fossilization process

    Energy Technology Data Exchange (ETDEWEB)

    Sousa Filho, Francisco Eduardo de [Departamento de Fisica, Universidade Regional do Cariri, Crato, CE (Brazil); Joao Herminio da Silva [Universidade Federal do Ceara, Cariri, Juazeiro do Norte, CE (Brazil); Saraiva, Antonio Alamo Feitosa; Brito, Deyvid Dennys S. [Departamento de Ciencias Biologicas, Universidade Regional do Cariri, Crato, CE (Brazil); Viana, Bartolomeu Cruz [Departamento de Fisica, Universidade Federal do Piaui, Teresina, PI, (Brazil); Abagaro, Bruno Tavares de Oliveira; Freire, Paulo de Tarso Cavalcante, E-mail: tarso@fisica.ufc.br [Departamento de Fisica, Universidade Federal do Ceara, Fortaleza, CE (Brazil)

    2011-12-15

    X-ray diffraction was combined with X-ray energy-dispersion, Fourier-transform infrared, and Raman spectroscopies to study the fossilization of a Cretaceous specimen of the plant Brachyphyllum castilhoi, a fossil from the Ipubi Formation, in the Araripe Sedimentary Basin, Northeastern Brazil. Among the possible fossilization processes, which could involve pyrite, silicon oxide, calcium oxide, or other minerals, we were able to single out pyritization as the central mechanism producing the fossil, more than 100 million years ago. In addition to expanding the knowledge of the Ipubi Formation, this study shows that, when combined with other experimental techniques, Raman spectroscopy is a valuable tool at the paleontologist's disposal. (author)

  12. X-ray diffraction study on thermal properties of crystal lattices in CeP and CeAs

    Energy Technology Data Exchange (ETDEWEB)

    Iwasa, Kazuaki; Kohgi, Masafumi [Department of Physics, Faculty of Science, Tokyo Metropolitan University, Hachioji, Tokyo (Japan); Ohsumi, Hiroyuki; Tajima, Keisuke; Takeuchi, Tetsuya; Haga, Yoshinori; Uesawa, Akihiro; Suzuki, Takashi

    1999-03-01

    X-ray diffraction studies at low temperatures have been performed in order to investigate thermal properties of crystal lattices in the low-carrier-density systems cerium monopnictides. CeP and CeAs show large crystal-lattice contractions with increasing temperatures up to about 120K and 90K, respectively. Due to the strong p-f mixing, the excited crystal {Gamma}{sub 8}-like state is expected to produce a shorter interatomic bond length between cerium ions and neighboring pnictogens than that realized by the {Gamma}{sub 7} ground state. The experimental results of the lattice contractions at low temperatures are explained by the thermal average of these crystal field states. (author)

  13. Measurements of transient electron density distributions by femtosecond X-ray diffraction; Messungen transienter Elektronendichteverteilungen durch Femtosekunden-Roentgenbeugung

    Energy Technology Data Exchange (ETDEWEB)

    Freyer, Benjamin

    2013-05-02

    This thesis concerns measurements of transient charge density maps by femtosecond X-ray diffraction. Different X-ray diffraction methods will be considered, particularly with regard to their application in femtosecond X-ray diffraction. The rotation method is commonly used in stationary X-ray diffraction. In the work in hand an X-ray diffraction experiment is demonstrated, which combines the method with ultrafast X-ray pulses. This experiment is the first implementation which makes use of the rotation method to map transient intensities of a multitude of Bragg reflections. As a prototype material Bismuth is used, which previously was studied frequently by femtosecond X-ray diffraction by measuring Bragg reflections successively. The experimental results of the present work are compared with the literature data. In the second part a powder-diffraction experiment will be presented, which is used to study the dynamics of the electron-density distribution on ultrafast time scales. The experiment investigates a transition metal complex after photoexcitation of the metal to ligand charge transfer state. Besides expected results, i. e. the change of the bond length between the metal and the ligand and the transfer of electronic charge from the metal to the ligand, a strong contribution of the anion to the charge transfer was found. Furthermore, the charge transfer has predominantly a cooperative character. That is, the excitation of a single complex causes an alteration of the charge density of several neighboring units. The results show that more than 30 transition-metal complexes and 60 anions contribute to the charge transfer. This collective response is a consequence of the strong coulomb interactions of the densely packed ions.

  14. X-ray diffraction study of boron produced by pyrolysis of boron tribromide

    Science.gov (United States)

    Rosenberg, David

    formation are not fully understood or agreed upon in the literature. In this research, the method of pyrolysis of boron tribromide (hydrogen reduction of boron tribromide) was used to deposit boron on a tantalum filament. The goal was to refine this method, or potentially use it in combination with a second method (amorphous boron crystallization), to the point where it is possible to grow large, high purity alpha-rhombohedral boron crystals with consistency. A pyrolysis apparatus was designed and built, and a number of trials were run to determine the conditions (reaction temperature, etc.) necessary for alpha-rhombohedral boron production. This work was focused on the x-ray diffraction analysis of the boron deposits; x-ray diffraction was performed on a number of samples to determine the types of boron (and other compounds) formed in each trial and to guide the choices of test conditions for subsequent trials. It was found that at low reaction temperatures (in the range of around 830-950 °C), amorphous boron was the primary form of boron produced. Reaction temperatures in the range of around 950-1000 °C yielded various combinations of crystalline boron and amorphous boron. In the first trial performed at a temperature of 950 °C, a mix of amorphous boron and alpha-rhombohedral boron was formed. Using a scanning electron microscope, it was possible to see small alpha-rhombohedral boron crystals (on the order of ~1 micron in size) embedded in the surface of the deposit. In subsequent trials carried out at reaction temperatures in the range of 950 °C -- 1000 °C, it was found that various combinations of alpha-rhombohedral boron, beta-rhombohedral boron, and amorphous boron were produced; the results tended to be unpredictable (alpha-rhombohedral boron was not produced in every trial), and the factors leading to success/failure were difficult to pinpoint. These results illustrate how sensitive of a process producing alpha-rhombohedral boron can be, and indicate that

  15. The First X-ray Diffraction Patterns of Clay Minerals from Gale Crater

    Science.gov (United States)

    Bristow, Thomas; Blake, David; Bish, David L.; Vaniman, David; Ming, Douglas W.; Morris, Richard V.; Chipera, Steve; Rampe, Elizabeth B.; Farmer, Jack, D.; Treiman, Allan H; hide

    2013-01-01

    The Mars Science Laboratory (MSL) Rover, Curiosity spent approx 150 sols at Yellowknife Bay (YKB) studying a section of fluvio-lacustrine sedimentary rocks (with potential indications of volcanic influence), informally known as the Yellowknife Bay formation. YKB lies in a distal region of the Peace Vallis alluvial fan, which extends from the northern rim of Gale Crater toward the dune field at the base of Mt Sharp. Sedimentological and stratigraphic observations are consistent with the Yellowknife Bay formation being part of a distal fan deposit, which could be as young as middle Hesperian to even early Amazonian in age (approx 3.5 to 2.5 Ga). The Yellowknife Bay formation hosts a unit of mudstone called the Sheepbed member. Curiosity obtained powdered rock samples from two drill holes in the Sheepbed Member, named John Klein and Cumberland, and delivered them to instruments in Curiosity. Data from CheMin, a combined X-ray diffraction (XRD)/X-ray fluorescence instrument (XRF), has allowed detailed mineralogical analysis of mudstone powders revealing a clay mineral component of approx 20 wt.% in each sample. The clay minerals are important indicators of paleoenvironmental conditions and sensitive recorders of post-depositional alteration processes. The XRD pattern of John Klein reveals a 021 band consistent with a trioctahedral phyllosilicate. A broad peak at approx 10A with a slight inflexion at approx 12A indicates the presence of 2:1 type clay minerals in the John Klein sample. The trioctahedral nature of the clay minerals, breadth of the basal reflection, and presence of a minor component with larger basal spacing suggests that John Klein contains a trioctahedral smectite (probably saponite), whose interlayer is largely collapsed because of the low-humidity conditions. The XRD patterns show no evidence of corrensite (mixed-layer chlorite/smectite) or chlorite, which are typical diagenetic products of trioctahedral smectites when subjected to burial and heating

  16. In situ X-ray diffraction of catalysts. Phase transformations of Cu/Cr-oxides with different initial structure under redox conditions

    Energy Technology Data Exchange (ETDEWEB)

    Krieger, T.A.; Plyasova, L.M.; Yurieva, T.M. [Boreskov Inst. of Catalysis, Novosibirsk (Russian Federation)

    2000-07-01

    The installation design and a chamber-reactor were proposed for laboratory-scale in situ X-ray diffraction studies of solid phase transformations. Dynamics of phase transformations was studied for low-temperature copper chromite under the action of the reaction medium. Common and distinctive features of the behavior of low- and high-temperature copper chromites under redox conditions at the temperature below 300 C were revealed. (orig.)

  17. Dynamic X-ray Diffraction to study the shock-induced α - ɛ Phase Transition in Iron

    Science.gov (United States)

    Branch, Brittany; Jensen, Brian

    2017-06-01

    Iron undergoes a well-known polymorphic phase transformation from a ferromagnetic body-centered cubic (α-phase) ground state to a non-magnetic hexagonal-closed pack (ɛ-phase) crystal structure at pressures exceeding 13 GPa. With the coupling of dynamic loading platforms and advanced light sources we were able to study the α- ɛ phase transition of iron using dynamic X-ray diffraction (XRD) now available at the Advanced Photon Source (APS). Specifically, front-surface plate impact experiments were performed using single and two-stage gun systems coupled to the X-ray beam line at the new Dynamic Compression Sector (DCS) at the APS. X-ray diffraction data obtained from multiple 80 picosecond width x-ray bunches were obtained for impact stresses that spanned the a-e region of the phase diagram. The experimental methods, results, and preliminary analysis will be presented. LA-UR - 17-21401.

  18. Two-dimensional time-resolved x-ray diffraction study of dual phase rapid solidification in steels

    Science.gov (United States)

    Yonemura, Mitsuharu; Osuki, Takahiro; Terasaki, Hidenori; Komizo, Yuichi; Sato, Masugu; Toyokawa, Hidenori; Nozaki, Akiko

    2010-01-01

    The high intensity heat source used for fusion welding creates steep thermal gradients of 100 °C/s from 1800 °C. Further, the influence of preferred orientation is important for the observation of a directional solidification that follows the dendrite growth along the ⟨100⟩ direction toward the moving heat source. In the present study, we observed the rapid solidification of weld metal at a time resolution of 0.01-0.1 s by a two-dimensional time-resolved x-ray diffraction (2DTRXRD) system for real welding. The diffraction rings were dynamically observed by 2DTRXRD with synchrotron energy of 18 keV while the arc passes over the irradiation area of the x-rays. The arc power output was 10 V-150 A, and the scan speed of the arc was 1.0 mm/s. The temperature rise in instruments was suppressed by a water-cooled copper plate under the specimen. Further, the temperature distribution of the weld metal was measured by a thermocouple and correlated with the diffraction patterns. Consequently, solidification and solid phase transformation of low carbon steels and stainless steels were observed during rapid cooling by 2DTRXRD. In the low carbon steel, the microstructure is formed in a two step process, (i) formation of crystallites and (ii) increase of crystallinity. In stainless steel, the irregular interface layer of δ/γ in the quenched metal after solidification is expected to show the easy movement of dendrites at a lower temperature. In carbide precipitation stainless steel, it is easy for NbC to grow on δ phase with a little undercooling. Further, a mistlike pattern, which differs from the halo pattern, in the fusion zone gave some indication of the possibilities to observe the nucleation and the early solidification by 2DTRXRD.

  19. An x-ray diffraction study of microstructural deformation induced by cyclic loading of selected steel

    Science.gov (United States)

    Fourspring, Patrick Michael

    X-ray double crystal diffractometry (XRDCD) and X-ray scanning diffractometry (XRSD) were used to assess cyclic microstructural deformation in a face centered cubic (fcc) steel (AISI304) and a body centered cubic (bcc) steel (SA508 class 2). The objectives of the investigation were to determine if X-ray diffraction could be used effectively to monitor cyclic microstructural deformation in polycrystalline Fe alloys and to study the distribution of the microstructural deformation induced by cyclic loading in these alloys. The approach used in the investigation was to induce fatigue damage in a material and to characterize the resulting microstructural deformation at discrete fractions of the fatigue life of the material. Also, characterization of microstructural deformation was carried out to identify differences in the accumulation of damage from the surface to the bulk, focusing on the following three regions: near surface (0-10 mum), subsurface (10-300 mum), and bulk. Characterization of the subsurface region was performed only on the AISI304 material because of the limited availability of the SA508 material. The results from the XRDCD data indicate a measurable change induced by fatigue from the initial state to subsequent states of both the AISI304 and the SA508 materials. The results from the XRSD data show similar but less coherent trends than the results from the XRDCD data. Therefore, the XRDCD technique was shown to be sensitive to the microstructural deformation caused by fatigue in steels; thus, the technique can be used to monitor fatigue damage in steels. In addition, for the AISI304 material, the level of cyclic microstructural deformation in the bulk material was found to be greater than the level in the near surface material. In contrast, previous investigations have shown that the deformation is greater in the near surface than the bulk for Al alloys and bcc Fe alloys.

  20. From virus structure to chromatin: X-ray diffraction to three-dimensional electron microscopy.

    Science.gov (United States)

    Klug, Aaron

    2010-01-01

    Early influences led me first to medical school with a view to microbiology, but I felt the lack of a deeper foundation and changed to chemistry, which in turn led me to physics and mathematics. I moved to the University of Cape Town to work on the X-ray crystallography of some small organic compounds. I developed a new method of using molecular structure factors to solve the crystal structure, which won me a research studentship to Trinity College Cambridge and the Cavendish Laboratory. There I worked on the austenite-pearlite transition in steel. This is governed by the dissipation of latent heat, and I ended up numerically solving partial differential equations. I used the idea of nucleation and growth during the phase change, which had its echo when I later tackled the assembly of Tobacco mosaic virus (TMV) from its constituent RNA and protein subunits. I wanted to move on to X-ray structure analysis of large biological molecules and obtained a Nuffield Fellowship to work in J.D. Bernal's department at Birkbeck College, London. There, I met Rosalind Franklin, who had taken up the study of TMV. I was able to interpret some of Franklin's beautiful X-ray diffraction patterns of the virus particle. From then on, my fate was sealed. After Franklin's untimely death in 1958, I moved in 1962 to the newly built MRC Laboratory of Molecular Biology in Cambridge, which, under Max Perutz, housed the original MRC unit from the Cavendish Laboratory. I was thus privileged to join the Laboratory at an early stage in its expansion and consequently able to take advantage of, and to help build up, its then unique environment of intellectual and technological sophistication. There I have remained ever since.

  1. Ultra-high resolution zone-doubled diffractive X-ray optics for the multi-keV regime.

    Science.gov (United States)

    Vila-Comamala, Joan; Gorelick, Sergey; Färm, Elina; Kewish, Cameron M; Diaz, Ana; Barrett, Ray; Guzenko, Vitaliy A; Ritala, Mikko; David, Christian

    2011-01-03

    X-ray microscopy based on Fresnel zone plates is a powerful technique for sub-100 nm resolution imaging of biological and inorganic materials. Here, we report on the modeling, fabrication and characterization of zone-doubled Fresnel zone plates for the multi-keV regime (4-12 keV). We demonstrate unprecedented spatial resolution by resolving 15 nm lines and spaces in scanning transmission X-ray microscopy, and focusing diffraction efficiencies of 7.5% at 6.2 keV photon energy. These developments represent a significant step towards 10 nm spatial resolution for hard X-ray energies of up to 12 keV.

  2. Determination of electronic and atomic properties of surface, bulk and buried interfaces: Simultaneous combination of hard X-ray photoelectron spectroscopy and X-ray diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Rubio-Zuazo, J., E-mail: rubio@esrf.fr [SpLine, Spanish CRG BM25 Beamline at the ESRF, ESRF, B.P. 220, F-38043 Grenoble (France); Instituto de Ciencia de Materiales de Madrid, ICMM, CSIC, Cantoblanco, E-28049 Madrid (Spain); Castro, G.R. [SpLine, Spanish CRG BM25 Beamline at the ESRF, ESRF, B.P. 220, F-38043 Grenoble (France); Instituto de Ciencia de Materiales de Madrid, ICMM, CSIC, Cantoblanco, E-28049 Madrid (Spain)

    2013-10-15

    Highlights: •We have developed a novel and exceptional tool for non-destructive characterization of bulk and buried interfaces that combine XRD and HAXPES. •We studied the correlation between the atomic, electronic and transport properties of oxygen deficient manganite thin films. •The diffraction data showed a cooperative tilt of the MnO{sub 6} block along the out-of-plane direction. •We shown the absence of the conventional basal plane rotation for the oxygen deficient samples. -- Abstract: Hard X-ray photoelectron spectroscopy (HAXPES) is a powerful novel emerging technique for bulk compositional, chemical and electronic properties determination in a non-destructive way. It benefits from the exceptionally large escape depth of high kinetic energy photoelectrons enabling the study of bulk and buried interfaces up to several tens of nanometres depth. Its advantage over conventional XPS is based on the long mean free path of high kinetic energetic photoelectrons. Using the advantage of tuneable X-ray radiation provided by synchrotron sources the photoelectron kinetic energy, i.e. the information depth can be changed and consequently electronic and compositional depth profiles can be obtained. The combination of HAXPES with an atomic structure sensitive technique, as X-ray diffraction, opens a new research field with great potential for many systems in which their electronic properties are intimately linked to their crystallographic structure. At SpLine, the Spanish CRG Beamline at the European Synchrotron Radiation Facility (ESRF) we have developed a novel and exceptional set-up that combine grazing incidence X-ray diffraction (GIXRD) and HAXPES. Both techniques can be operated simultaneously on the same sample and using the same excitation source. The set-up includes a heavy 2S+3D diffractometer and UHV chamber equipped with an electrostatic analyzer. The UHV chamber has also MBE evaporation sources, an ion gun, a LEED optic, a sample heating and cooling

  3. Standard test method for determining the effective elastic parameter for X-ray diffraction measurements of residual stress

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    1998-01-01

    1.1 This test method covers a procedure for experimentally determining the effective elastic parameter, Eeff, for the evaluation of residual and applied stresses by X-ray diffraction techniques. The effective elastic parameter relates macroscopic stress to the strain measured in a particular crystallographic direction in polycrystalline samples. Eeff should not be confused with E, the modulus of elasticity. Rather, it is nominally equivalent to E/(1 + ν) for the particular crystallographic direction, where ν is Poisson's ratio. The effective elastic parameter is influenced by elastic anisotropy and preferred orientation of the sample material. 1.2 This test method is applicable to all X-ray diffraction instruments intended for measurements of macroscopic residual stress that use measurements of the positions of the diffraction peaks in the high back-reflection region to determine changes in lattice spacing. 1.3 This test method is applicable to all X-ray diffraction techniques for residual stress measurem...

  4. Small-angle techniques for the asymptotic analysis of X-ray diffraction peaks

    Energy Technology Data Exchange (ETDEWEB)

    Ciccariello, S. (Padua Univ. (Italy). Dipt. di Fisica ' G. Galilei' )

    1990-03-01

    Any wide-angle X-ray scattering (WAXS) peak, relevant to a powder sample of crystallites with negligible internal disorder, is the Fourier transform of the so-called oriented stick probability function (oSPF) of the filled part of the sample, with the stick orientated along the reflexion direction. From this observation the following consequences are obtained: The correlation function used in small-angle X-ray scattering (SAXS) is the average of the former oSPF's over all possible stick orientations; any peak profile asymptotically vanishes as S{sub r}h{sup -2}, where S{sub r} is the (specific) area of the interphase surface presented by the sample along the reflexion direction; oscillatory deviations, behaving as S{sub r,parallel}cos (hL)h{sup -2}, are present only when a subset (having area S{sub r,parallel}) of the interface, after having been translated by L along the reflexion direction, superposes on itself; the angularity of the interphase surface can be measured by a natural modification of the Porod integral relation. For samples really isotropic, the above quantities should not depend on the reflexion direction and thus they should be equal to those measured by SAXS experiments. These results are applied to three ideal isotropic powder samples made up, respectively, of monodisperse spherical, cubic and cylindrical crystallites as well as to the analysis of two WAXS peaks diffracted by two real samples of zirconia powders. (orig.).

  5. Metrology of Epitaxial Thin Films and Periodic Nanostructures using High Resolution X-Ray Diffraction Techniques

    Science.gov (United States)

    Medikonda, Manasa

    The continued scaling of device size to achieve higher performance and/or lower power operation at lower cost is driving research and development into new, 3D transistor structures such as the FinFET. This research and development effort is highlighting the need for new, advanced measurement capability that is highly accurate, reliable, rapid, and nondestructive. Periodic arrays of fin structures enable process monitoring at each level of fabrication and the maintenance of overall device yield. High resolution x-ray diffraction (HR XRD) has been shown to provide unique capability of characterizing blanket thin films and structural parameters of periodic arrays of fins fabricated in single crystal materials. Application of HR XRD techniques to characterize fin structures with critical dimensions of 1x-2x nm has been very limited. The main objective of my research is to develop and apply HR XRD techniques that analyze critical parameters such as the lithographic pitch, pitch walking, sidewall slope, and fin top width in arrays of advanced fin structures. This research also investigates the stress state of initially pseudomorphic epilayers at the top of the fin, and identification of defects. The results for non-patterned epitaxial fully strained SiGe and GeSn alloys are presented and the methods of detecting periodicity, strain state and shape of arrays of lithographically patterned silicon and silicon-germanium fins are demonstrated using synchrotron source and laboratory x-ray diffractometers.

  6. Redetermination of LaZn5 based on single crystal X-ray diffraction data

    Directory of Open Access Journals (Sweden)

    Igor Oshchapovsky

    2012-01-01

    Full Text Available The crystal structure of the already known binary title compound LaZn5 (lanthanum pentazinc (space group P6/mmm, Pearson symbol hP6, CaCu5 structure type has been redetermined from single-crystal X-ray diffraction data. In contrast to previous determinations based on X-ray powder data [Nowotny (1942. Z. Metallkd. 34, 247–253; de Negri et al. (2008. Intermetallics, 16, 168–178], where unit-cell parameters and assignment of the structure type were reported, the present study reveals anisotropic displacement parameters for all atoms. The crystal structure consists of three crytallographically distinct atoms. The La atom (Wyckoff site 1a, site symmetry 6/mmm is surrounded by 18 Zn atoms and two La atoms. The coordination polyhedron around one of the Zn atoms (Wyckoff site 2c, site symmetry -6m2 is an icosahedron made up from three La and nine Zn atoms. The other Zn atom (Wyckoff site 3g, site symmetry mmm is surrounded by four La and eight Zn atoms. Bonding between atoms is explored by means of the TB–LMTO–ASA (tight-binding linear muffin-tin orbital atomic spheres approximation program package. The positive charge density is localized around La atoms, and the negative charge density is around Zn atoms, with weak covalent bonding between the latter.

  7. FTIR spectroscopy and X-ray powder diffraction characterization of microcrystalline cellulose obtained from alfa fibers

    Directory of Open Access Journals (Sweden)

    Trache D.

    2013-07-01

    Full Text Available Many cereal straws have been used as raw materials for the preparation of microcrystalline cellulose (MCC. These raw materials were gradually replaced with wood products; nevertheless about 10% of the world overall pulp production is obtained from non-wood raw material. The main interest in pulp made from straw is that it provides excellent fibres for different industries with special properties, and that it is the major available source of fibrous raw material in some geographical areas. The aim of the present work was to characterize microcrystalline cellulose prepared from alfa fibers using the hydrolysis process. The products obtained are characterized with FTIR spectroscopy and X-ray powder diffraction. As a result, FTIR spectroscopy is an appropriate technique for studying changes occurred by any chemical treatment. The spectrum of alfa grass stems shows the presence of lignin and hemicelluloses. However, the cellulose spectrum indicates that the extraction of lignin and hemicellulose was effective. The X-ray analysis indicates that the microcrystalline cellulose is more crystalline than the source material.

  8. Synchrotron X-Ray Diffraction Studies of Olivine from Comet Wild 2

    Science.gov (United States)

    2008-01-01

    We have analyzed a collection of the Comet Wild 2 coma grains returned by the NASA Stardust Mission, using micro-area Laue diffraction equipment. The purpose of the diffraction experiment is to permit the structure refinement of olivine including site occupancies. In addition to the intrinsic importance of the olivine structures for revealing the thermal history of Wild 2 materials, we wish to test reports that olivine recovered after hypervelocity capture in silica aerogel has undergone a basic structural change due to capture heating [1]. The diffraction equipment placed at beam line BL- 4B1 of PF, KEK was developed with a micropinhole and an imaging plate (Fuji Co. Ltd.) using the Laue method combined with polychromatic X-ray of synchrotron radiation operated at energy of 2.5 GeV. The incident beam is limited to 1.6 m in diameter by a micropinhole set just upstream of the sample [2, 3]. It is essential to apply a microbeam to obtain diffracted intensities with high signal to noise ratios. This equipment has been successfully applied to various extraterrestrial materials, including meteorites and interplanetary dust particles [4]. The Laue pattern of the sample C2067,1,111,4 (Fig. 1) was successfully taken on an imaging plate after a 120 minute exposure (Fig. 2).

  9. Grain-resolved elastic strains in deformed copper measured by three-dimensional X-ray diffraction

    DEFF Research Database (Denmark)

    Oddershede, Jette; Schmidt, Søren; Poulsen, Henning Friis

    2011-01-01

    This X-ray diffraction study reports the grain-resolved elastic strains in about 1000 randomly oriented grains embedded in a polycrystalline copper sample. Diffraction data were collected in situ in the undeformed state and at a plastic strain of 1.5% while the sample was under tensile load...

  10. X-ray diffraction analysis and in vitro characterization of the UAM2 protein from Oryza sativa

    DEFF Research Database (Denmark)

    Welner, Ditte Hededam; Tsai, Alex Yi-Lin; DeGiovanni, Andy M.

    2017-01-01

    protein from Oryza sativa (OsUAM2) were undertaken. Here, X-ray diffraction data are reported, as well as analysis of the oligomeric state in the crystal and in solution. OsUAM2 crystallizes readily but forms highly radiation-sensitive crystals with limited diffraction power, requiring careful low...

  11. X-ray diffraction study of the structure and thermal parameters of the ternary Au-Ag-Pd alloys

    Energy Technology Data Exchange (ETDEWEB)

    Ziya, A.B. [Department of Physics, Bahauddin Zakariya University, Multan-60800 (Pakistan) and Institute of Materials Science, University of Tsukuba, Tsukuba 305-8573 (Japan)]. E-mail: amer_ziya@yahoo.com; Ohshima, K. [Institute of Materials Science, University of Tsukuba, Tsukuba 305-8573 (Japan)

    2006-11-30

    In situ X-ray diffraction experiments were performed on six samples of the ternary Au-Ag-Pd alloys (with A1 structure) having different compositions using a Cu-target. The integrated intensity data obtained in the temperature range of 373-1200K was utilized to determine the lattice parameters and the thermal parameters like Einstein's temperatures ({theta}{sub E}), the mean-square amplitudes (u{sup 2}-bar (T)) and the coefficients of thermal expansion with a high accuracy. The lattice parameter showed a small negative deviation from the Vegard's rule. It is also found that the mean-square amplitudes are independent of the static displacements. The mean-square amplitudes of vibration and the linear thermal expansion follow the classical Gruneisen relationship in these alloys.

  12. In situ X-ray diffraction study of crystallization process of GeSbTe thin films during heat treatment

    Energy Technology Data Exchange (ETDEWEB)

    Kato, Naohiko [Toyota Central R and D Labs., Inc., Nagakute, Aichi 480-1192 (Japan)]. E-mail: e0957@mosk.tytlabs.co.jp; Konomi, Ichiro [Toyota Central R and D Labs., Inc., Nagakute, Aichi 480-1192 (Japan); Seno, Yoshiki [Toyota Central R and D Labs., Inc., Nagakute, Aichi 480-1192 (Japan); Motohiro, Tomoyoshi [Toyota Central R and D Labs., Inc., Nagakute, Aichi 480-1192 (Japan)

    2005-05-15

    The crystallization processes of the Ge{sub 2}Sb{sub 2}Te{sub 5} thin film used for PD and DVD-RAM were studied in its realistic optical disk film configurations for the first time by X-ray diffraction using an intense X-ray beam of a synchrotron orbital radiation facility (SPring-8) and in situ quick detection with a Position-Sensitive-Proportional-Counter. The dependence of the amorphous-to-fcc phase-change temperature T{sub 1} on the rate of temperature elevation R{sub et} gave an activation energy E{sub a}: 0.93 eV much less than previously reported 2.2 eV obtained from a model sample 25-45 times thicker than in the real optical disks. The similar measurement on the Ge{sub 4}Sb{sub 1}Te{sub 5} film whose large reflectance change attains the readability by CD-ROM drives gave E{sub a}: 1.13 eV with larger T{sub 1} than Ge{sub 2}Sb{sub 2}Te{sub 5} thin films at any R{sub et} implying a lower sensitivity in erasing as well as a better data stability of the phase-change disk.

  13. Non-destructive in situ study of "Mad Meg" by Pieter Bruegel the Elder using mobile X-ray fluorescence, X-ray diffraction and Raman spectrometers

    Science.gov (United States)

    Van de Voorde, Lien; Van Pevenage, Jolien; De Langhe, Kaat; De Wolf, Robin; Vekemans, Bart; Vincze, Laszlo; Vandenabeele, Peter; Martens, Maximiliaan P. J.

    2014-07-01

    "Mad Meg", a figure of Flemish folklore, is the subject of a famous oil-on-panel painting by the Flemish renaissance artist Pieter Bruegel the Elder, exhibited in the Museum Mayer van den Bergh (Antwerp, Belgium). This article reports on the in situ chemical characterization of this masterpiece by using currently available state-of-the-art portable analytical instruments. The applied non-destructive analytical approach involved the use of a) handheld X-ray fluorescence instrumentation for retrieving elemental information and b) portable X-ray fluorescence/X-ray diffraction instrumentation and laser-based Raman spectrometers for obtaining structural/molecular information. Next to material characterization of the used pigments and of the different preparation layers of the painting, also the verification of two important historical iconographic hypotheses is performed concerning the economic way of painting by Brueghel, and whether or not he used blue smalt pigment for painting the boat that appears towards the top of the painting. The pigments identified are smalt pigment (65% SiO2 + 15% K2O + 10% CoO + 5% Al2O3) for the blue color present in all blue areas of the painting, probably copper resinate for the green colors, vermillion (HgS) as red pigment and lead white is used to form different colors. The comparison of blue pigments used on different areas of the painting gives no differences in the elemental fingerprint which confirms the existing hypothesis concerning the economic painting method by Bruegel.

  14. Determining grain resolved stresses in polycrystalline materials using three-dimensional X-ray diffraction

    DEFF Research Database (Denmark)

    Oddershede, Jette; Schmidt, Søren; Poulsen, Henning Friis

    2010-01-01

    An algorithm is presented for characterization of the grain resolved (type II) stress states in a polycrystalline sample based on monochromatic X-ray diffraction data. The algorithm is a robust 12-parameter-per-grain fit of the centre-of-mass grain positions, orientations and stress tensors...... including error estimation and outlier rejection. The algorithm is validated by simulations and by two experiments on interstitial free steel. In the first experiment, using only a far-field detector and a rotation range of 2 × 110°, 96 grains in one layer were monitored during elastic loading and unloading....... Very consistent results were obtained, with mean resolutions for each grain of approximately 10 µm in position, 0.05° in orientation, and 8, 20 and 13 × 10-5 in the axial, normal and shear components of the strain, respectively. The corresponding mean deviations in stress are 30, 50 and 15 MPa...

  15. X-ray diffraction study on microstructures of shot/laser-peened AISI316 stainless steel

    Energy Technology Data Exchange (ETDEWEB)

    Kumagai, Masayoshi, E-mail: mkumagai@tcu.ac.jp [Tokyo City University, Department of Mechanical Systems Engineering (Japan); Akita, Koichi [Quantum Beam Science Directorate, Japan Atomic Energy Agency (Japan); Itano, Yuta [Tokyo City University, Graduate School of Engineering (Japan); Imafuku, Muneyuki; Ohya, Shin-ichi [Tokyo City University, Department of Mechanical Systems Engineering (Japan)

    2013-11-15

    Microstructural features of AISI316 stainless steels processed by shot peening (SP) and laser peening (LP) were studied using X-ray diffraction line profile analyses. Both specimens exhibited similar compressive residual stress profiles. Although the number of dislocations was increased and the crystallites were refined with both processes, the dislocation density in the SP specimen was significantly greater than that in the LP specimen. The crystallite size in the SP specimen was one-third that in the LP specimen. The SP process induced martensite transformation. The variations in the microstructural features differed between samples subjected to the two processes. The SP process resulted in a greater variation in the microstructural features in a sample in which residual stresses similar to that induced by the LP process were induced. Thus, the variations in the microstructural features differed depending on the deformation process.

  16. X-Ray Diffraction and Structural Properties of Aqueous Solutions of Divalent Metal-Chlorides

    Science.gov (United States)

    Caminiti, R.; Licheri, G.; Paschina, G.; Piccaluga, G.; Pinna, G.

    1980-12-01

    X-ray diffraction data are reported for aqueous solutions of CaCl2 (6.30 M), CdCl2 (0.87 and 1.26 M) and NiCl2 (1.96 and 3.88 M). The highly concentrated CaCl2 solution shows a medium range order resembling that of the corresponding hydrate crystal. The CdCl2 solutions are characterized by the presence of complexes with chloride ions in the first coordination sphere of the cation. In NiCl2 solutions, a first sphere Ni-Cl coordination can be excluded and the existence of six Ni-H2O nearest neighbour contacts is clearly confirmed. In these solutions no evidence was found for the existence of highly ordered structures; hexa-aquo cations interact with external water molecules and, at the highest concentration, some outer sphere Ni-Cl correlation is possible as due to packing.

  17. Transmission diffractive patterns of large microchannel plates at soft X-ray energies

    Science.gov (United States)

    Mazuritskiy, M. I.; Dabagov, S. B.; Lerer, A. M.; Dziedzic-Kocurek, K.; Sokolov, A.; Coreno, M.; Turchini, S.; D'Elia, A.; Sacchi, M.; Marcelli, A.

    2017-07-01

    In this contribution we compare experimental and theoretical diffractive patterns of Micro Channel Plates (MCPs) in transmission. We evaluate the transmission efficiency of different optical devices at different energies of the primary X-ray radiation in the normal incidence geometry. Data were collected performing angular scans of both the MCP device and of the detector in the range of a few degrees. We analyzed MCPs of 33 mm and 20 mm diameter and ∼300 μm thickness, having circular micro-channels of 3.4 μm directed normal to the MCP surface. Quite symmetric patterns of increasing complexity from high to low photon energy have been collected. Their shape and intensity are in reasonable agreement with preliminary simulations.

  18. Ray-tracing analysis of diffractive-refractive X-ray optics.

    Science.gov (United States)

    Artemiev, Nikolay; Hrdý, Jaromir; Peredkov, Serguei; Artemev, Alexander

    2004-03-01

    Ray-tracing simulations of mistuned sagittal diffractive-refractive X-ray lenses (DRXL) are presented. In this article, firstly the characteristic aberrations for various types of crystal misalignments within one-crystal and four-crystal DRXLs are considered, and the sensitivity of such an optical system to the mutual misalignment of its components is discussed. The simulations reveal that a DRXL is not too sensitive to the adjustment of its components. In the second part of this article the performance of such lenses with ideal and approximate profiles is examined. Comparative analysis of parabolic and cylindrical DRXLs showed that, in the case when the linear source size is comparable with the acceptance of the lens, the performances of parabolic and cylindrical DRXLs are practically the same.

  19. X-ray diffraction of slag-based sodium salt waste forms

    Energy Technology Data Exchange (ETDEWEB)

    Langton, C. A. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Missimer, D. M. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2014-09-30

    The attached report documents sample preparation and x-ray diffraction results for a series of cement and blended cement matrices prepared with either water or a 4.4 M Na salt solution. The objective of the study was to provide initial phase characterization for the Cementitious Barriers Partnership reference case cementitious salt waste form. This information can be used to: 1) generate a base line for the evolution of the waste form as a function of time and conditions, 2) potentially to design new binders based on mineralogy of the binder, 3) understand and predict anion and cation leaching behavior of contaminants of concern, and 4) predict performance of the waste forms for which phase solubility and thermodynamic data are available.

  20. UV/X-Ray Diffraction Radiation for non-intercepting Micron-Scale Beam Size Measurement

    CERN Document Server

    -; Lefevre, T; Karataev, P; Billing, M

    2012-01-01

    Diffraction radiation (DR) is produced when a relativistic charged particle moves in the vicinity of a medium. The electric field of the charged particle polarizes the target atoms which then oscillate, emitting radiation with a very broad spectrum. The spatial-spectral properties of DR are sensitive to a range of electron beam parameters. Furthermore, the energy loss due to DR is so small that the electron beam parameters are unchanged. Therefore DR can be used to develop non-invasive diagnostic tools. The aim of this project is to measure the transverse (vertical) beam size using incoherent DR. To achieve the micron-scale resolution required by CLIC, DR in UV and X-ray spectral-range must be investigated. During the next few years, experimental validation of such a scheme will be conducted on the CesrTA at Cornell University, USA. Here we present the current status of the experiment preparation.

  1. Strategies for Time-resolved X-ray Diffraction of Phase Transitions with Laser Compression

    Science.gov (United States)

    Benedetti, Laura Robin; Eggert, J. H.; Bradley, D. K.; Bell, P. M.; Kilkenny, J. D.; Palmer, N.; Petre, R. B.; Rygg, J. R.; Sorce, C.; Collins, G. W.; Boehly, T. R.

    2017-10-01

    As part of a program to document kinetics of phase transitions under laser-driven dynamic compression, we are designing a platform to make multiple x-ray diffraction measurements during a single laser experiment. Our plans include experimental development at Omega-EP and eventual implementation at NIF. We will present our strategy for designing a robust platform that can effectively document a wide variety of phase transformations by utilizing both streaked and multiple-frame imaging detectors. Preliminary designs utilize a novel CMOS detector designed by Sandia National Lab. Our initial experiments include scoping studies that will focus on photometrics and shielding requirements in the high EMP environment close to the target. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344. Lawrence Livermore National Security, LLC, LLNL-ABS-734470.

  2. Crystallization and preliminary X-ray diffraction analysis of Leishmania major dihydroorotate dehydrogenase.

    Science.gov (United States)

    Cordeiro, Artur T; Feliciano, Patricia R; Nonato, M Cristina

    2006-10-01

    Dihydroorotate dehydrogenases (DHODHs) are flavin-containing enzymes that catalyze the oxidation of L-dihydroorotate to orotate, the fourth step in the de novo pyrimidine nucleotide synthesis pathway. In this study, DHODH from Leishmania major has been crystallized by the vapour-diffusion technique using lithium sulfate as the precipitating agent. The crystals belong to space group P6(1), with unit-cell parameters a = 143.7, c = 69.8 A. X-ray diffraction data were collected to 2.0 A resolution using an in-house rotating-anode generator. Analysis of the solvent content and the self-rotation function indicate the presence of two molecules in the asymmetric unit. The structure has been solved by the molecular-replacement technique.

  3. Arabidopsis receptor-like cytoplasmic kinase BIK1: purification, crystallization and X-ray diffraction analysis.

    Science.gov (United States)

    Lal, Neeraj K; Fisher, Andrew J; Dinesh-Kumar, Savithramma P

    2016-10-01

    Receptor-like cytoplasmic kinases (RLCKs) in Arabidopsis play a central role in the integration of signaling input from various growth and immune signaling pathways. BOTRYTIS-INDUCED KINASE 1 (BIK1), belonging to the RLCK family, is an important player in defense against bacterial and fungal pathogens and in ethylene and brassinosteroid hormone signaling. In this study, the purification and crystallization of a first member of the class VI family of RLCK proteins, BIK1, are reported. BIK1 was crystallized using the microbatch-under-oil method. X-ray diffraction data were collected to 2.35 Å resolution. The crystals belonged to the monoclinic space group C2, with two monomers per asymmetric unit.

  4. Fossilization in Geopark Araripe studied through X-ray diffraction, scanning microscopy and thermogravimetric analysis

    CERN Document Server

    Lima, Ricardo J C; Macedo, Zélia S; Sasaki, José M; Saraiva, Antônio A F

    2008-01-01

    The Geopark Araripe, located in Northeastern Brazil, is the first UNESCO Natural Park in the South hemisphere and a world-famous fossil deposit of the Early Cretaceous period (approximately 120 million years). Fossilized fish fauna in Geopark Araripe is found inside of sedimentary rocks in three-dimensional forms. In the present study sedimentary rocks and fossil fish Rhacolepis bucalis have been carefully analysed by means of X-ray powder diffraction, scanning electron microscopy and termogravimetric analysis. Mineralogical composition of the fossil fish was explained in terms of facts occurred at the initial stages of the opening of the South Atlantic and the oceanic hydrothermal phenomena (``black smoker'', ``white smoker'' and warm-water events). The occurrence of organic substance was, for the first time, evaluated in collapsed internal elements (intestinal and muscles) by termogravimetric analysis.

  5. Crystallization and Preliminary X-ray Diffraction Analysis of motif N from Saccharomyces cerevisiae Dbf4

    Energy Technology Data Exchange (ETDEWEB)

    Matthews, L.; Duong, A; Prasad, A; Duncker, B; Guarne, A

    2009-01-01

    The Cdc7-Dbf4 complex plays an instrumental role in the initiation of DNA replication and is a target of replication-checkpoint responses in Saccharomyces cerevisiae. Cdc7 is a conserved serine/threonine kinase whose activity depends on association with its regulatory subunit, Dbf4. A conserved sequence near the N-terminus of Dbf4 (motif N) is necessary for the interaction of Cdc7-Dbf4 with the checkpoint kinase Rad53. To understand the role of the Cdc7-Dbf4 complex in checkpoint responses, a fragment of Saccharomyces cerevisiae Dbf4 encompassing motif N was isolated, overproduced and crystallized. A complete native data set was collected at 100 K from crystals that diffracted X-rays to 2.75 {angstrom} resolution and structure determination is currently under way.

  6. Triple crystal x-ray diffraction analysis of chemical-mechanical polished gallium arsenide

    Science.gov (United States)

    Wang, V. S.; Matyi, R. J.

    1992-12-01

    High-resolution triple crystal x-ray diffraction has been used to monitor the magnitude of diffuse scattering from chemical-mechanical (CM) polished GaAs. The diffuse scattering, which is attributed to kinematic scattering arising from polish-induced crystallographic defects, was found to be only slightly affected when each of four CM polish parameters (bromine concentration in Br2/methanol, total polish time, polish pad rotation speed, and force on sample) was varied individually. The combined effect of increases in both the pad rotation speed and the force on the sample increased the magnitude of the diffuse scattering, suggesting the generation of mechanical damage. When all four variables were increased to their maximum values, the diffuse scattering increased dramatically and became anisotropic. We have expressed the magnitude of the diffuse scattering in terms of an ``excess intensity'' in reciprocal space to provide a semi-quantitative relation between CM polish parameters and the generation of polish-induced damage.

  7. X-ray diffraction patterns in human dentin, enamel and synthetic apatites related to Zn concentration.

    Science.gov (United States)

    Lappalainen, R; Knuuttila, M

    1981-12-01

    The crystallization of human dentin and enamel containing different concentrations of Zn was studied using X-ray diffraction analysis. The concentrations of Ca, Mg, Mn, Fe, Zn, Cu, Co, Ni, Sr and Pb in the samples were determined by atomic absorption spectrophotometry. The concentration of F was assayed with a combination fluoride electrode. The increase of the Zn concentration (microgram/g) from 150 to 572 in dentin was found to intensify apatite reflections indicating changes parallel to c-axis. A slight increase parallel to a-axis (or better crystallization) of lattices was demonstrated in both dentin and enamel. The increase of Zn concentration from 164 microgram/g to 692 microgram/g in enamel weakened 002 and 112 reflections. The effect of Zn on the crystallinity of synthetic apatite prepared at 37 degrees C was of the same kind as its effect on the dentin.

  8. High-pressure X-ray diffraction study of bulk- and nanocrystalline GaN

    DEFF Research Database (Denmark)

    Jorgensen, J.E.; Jakobsen, J.M.; Jiang, Jianzhong

    2003-01-01

    Bulk- and nanocrystalline GaN have been studied by high-pressure energy-dispersive X-ray diffraction. Pressure-induced structural phase transitions from the wurtzite to the NaCl phase were observed in both materials. The transition pressure was found to be 40 GPa for the bulk-crystalline GaN, while...... the wurtzite phase was retained up to 60 GPa in the case of nanocrystalline GaN. The bulk moduli for the wurtzite phases were determined to be 187 ( 7) and 319 ( 10) GPa for the bulk- and nanocrystalline phases, respectively, while the respective NaCl phases were found to have very similar bulk moduli [ 208...

  9. X-ray diffraction, FTIR, UV-VIS and SEM studies on chromium (III) complexes

    Energy Technology Data Exchange (ETDEWEB)

    Mishra, Ashutosh; Dwivedi, Jagrati, E-mail: hemu.dwi@gmail.com; Shukla, Kritika [School of Physics, Devi Ahilya University, Khandwa Road, Indore-452001 (India)

    2015-06-24

    Five Chromium (III) complexes have been prepared using Schiff base ligands which derived from benzoin and five different amino acids (H{sub 2}N-R). Samples were characterized by XRD, FTIR, UV-VIS and SEM method. X-Ray diffraction pattern analyzed that all chromium (III) complexes have hexagonal structure and crystalline, in nature, using Bruker D8 Advance instrument. Using VERTAX 70, FTIR spectroscopy reveals that Samples have (C=N), (C-O), (M-N) and (M-O) bonds in the range of 4000-400cm{sup −1}. UV-VIS spectroscopy give information that samples absorb the visible light which is in the range of 380-780nm. For this, Lambda 960 spectrometer used. SEM is designed for studying of the solid objects, using JEOL JSM 5600 instrument.

  10. Spectral, DFT and X-ray diffraction studies on regioselective synthesis of thiazolo-quinazoline system

    Science.gov (United States)

    Gautam, Deepika; Gautam, Poonam; Chaudhary, R. P.

    2017-10-01

    Unsymmetrical quinazoline-3-thione 2, obtained from one pot condensation of 2-tetralone, p-chlorobenzaldehyde and thiourea in acidic medium, on reaction with α-halo acids afforded thiazolo-quinazoline derivatives 3, 7 and not their regioisomers 4 and 8 respectively. The cyclised product obtained by the reaction of thione 2 with 1,2-dibromoethane has been assigned structure 5. Condensation of thione 2 with 3-chloropropionic acid and 1,3-dibromopropane furnished thiazino-quinazoline derivatives 10 and 12 instead of their regioisomers 11 and 13 respectively. The structure of the cyclised products has been established by means of spectral data (IR, NMR and Mass). X-ray diffraction studies of a representative compound supported our claim on structural assignments. DFT studies on regioisomers further validated the claim for assigned structures. The reaction of thione 2 with 3-chloropropionc acid in presence of acetic acid yielded thiazinan-4-one 10.

  11. An Improved X-ray Diffraction Method For Cellulose Crystallinity Measurement

    Energy Technology Data Exchange (ETDEWEB)

    Ju, Xiaohui; Bowden, Mark E.; Brown, Elvie E.; Zhang, Xiao

    2015-06-01

    We show in this work a modified X-ray diffraction method to determine cellulose crystallinity index (CrI). Nanocrystalline cellulose (NCC) dervided from bleached wood pulp was used as a model substrate. Rietveld refinement was applied with consideration of March-Dollase preferred orientation at the (001) plane. In contrast to most previous methods, three distinct amorphous peaks identified from new model samples which are used to calculate CrI. A 2 theta range from 10° to 75° was found to be more suitable to determine CrI and crystallite structural parameters such as d-spacing and crystallite size. This method enables a more reliable measurement of CrI of cellulose and may be applicable to other types of cellulose polymorphs.

  12. Contributions to the defocusing effect on pole figure measurements by X-ray diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Palacios G, J.; Salat F, R. S.; Jimenez J, A.; Kryshtab, T., E-mail: palacios@esfm.ipn.mx [Instituto Politecnico Nacional, Escuela Superior de Fisica y Matematicas, Av. IPN s/n, 07738 Mexico D. F. (Mexico)

    2015-07-01

    A simple method, considering a parallel beam approximation has been made to reproduce the main features of the defocusing effect, observed when pole figures are measured with the Schulz reflection technique using X-ray diffraction. A Lorentzian curve was used to approximate the primary beam profile. This method applied to low index reflections of copper and silver shows qualitatively and partially quantitatively, the extent the elongation of the ellipse resulting from the intersection of the beam with the tilted sample causes the defocusing effect. Differences observed experimentally are attributed mainly to the divergence of the beam, but also partially to the particular primary beam profile. Additionally, measurements with two different vertical heights of the receiving slit, i. e. the measured arch length of the Debye-Scherrer ring, indicate that this parameter plays no role in defocusing. (Author)

  13. Tensile behavior of orthorhombic alpha ''-titanium alloy studied by in situ X-ray diffraction

    DEFF Research Database (Denmark)

    Wang, X.D.; Lou, H.B.; Ståhl, Kenny

    2010-01-01

    The tensile behavior of a Ti-11%Zr-14%Nb-10%Sn alloy with pure orthorhombic alpha '' phase was studied by in situ X-ray diffraction using synchrotron radiation. It is found that no phase transformation happens during the whole tensile process. The "double-yielding" platforms of this alloy...... are indeed due to a low stress yielding (similar to 400 MPa) followed with a significant work-hardening before necking and fracture. In this process, the [0 2 2] orientation of grains more approaches the tensile direction and the [2 0 0] moves to the transverse, causing the lattice parameter a to be shrunk......, and b and c elongated, and the formation of texture. The similar texture can also be produced upon cold rolling by which the yield strength of the alpha '' phase is largely improved to be over 900 MPa....

  14. Elastic constant measurement in supported W/Cu multilayer thin films by X-ray diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Villain, P.; Goudeau, P.; Renault, P.O.; Badawi, K.F. [LMP-UMR, CNRS, Univ. de Poitiers, Futuroscope (France)

    2002-07-01

    Elasticity of reduced dimension materials remains misunderstood since both experimental and theoretical studies on this subject are difficult to perform. Numerous experiments realised in the early 90's evidenced ''elastic anomalies'' in small period multilayer systems: ''supermodulus'', breakdown of the Poisson's effect. The polemic raised by these observations lead us to develop a method to study the elastic constants in thin films on substrates; it combines X-ray diffraction and in situ tensile testing. The results presented in this paper deal with the size effect on the elastic properties in tungsten layers with a thickness of a few nanometers. For that purpose, W/Cu multilayers with various thickness periods {lambda} ranging from 3 to 24 nm have been analysed. (orig.)

  15. Hydride reorientation in Zircaloy-4 examined by in situ synchrotron X-ray diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Weekes, H.E. [Department of Materials, Royal School of Mines, Imperial College London, Prince Consort Road, London SW7 2BP (United Kingdom); Jones, N.G. [Department of Materials Science and Metallurgy, University of Cambridge, 27 Charles Babbage Road, Cambridge CB3 0FS (United Kingdom); Lindley, T.C. [Department of Materials, Royal School of Mines, Imperial College London, Prince Consort Road, London SW7 2BP (United Kingdom); Dye, D., E-mail: david.dye@imperial.ac.uk [Department of Materials, Royal School of Mines, Imperial College London, Prince Consort Road, London SW7 2BP (United Kingdom)

    2016-09-15

    The phenomenon of stress-reorientation has been investigated using in situ X-ray diffraction during the thermomechanical cycling of hydrided Zircaloy-4 tensile specimens. Results have shown that loading along a sample’s transverse direction (TD) leads to a greater degree of hydride reorientation when compared to rolling direction (RD)-aligned samples. The elastic lattice micro-strains associated with radially oriented hydrides have been revealed to be greater than those oriented circumferentially, a consequence of strain accommodation. Evidence of hydride redistribution after cycling, to α-Zr grains oriented in a more favourable orientation when under an applied stress, has also been observed and its behaviour has been found to be highly dependent on the loading axis. Finally, thermomechanical loading across multiple cycles has been shown to reduce the difference in terminal solid solubility of hydrogen during dissolution (TSS{sub D,H}) and precipitation (TSS{sub P,H}).

  16. X-Ray diffraction, spectroscopy and thermochemical characterization of the pharmaceutical paroxetine nitrate salt

    Science.gov (United States)

    Carvalho, Paulo S.; de Melo, Cristiane C.; Ayala, Alejandro P.; Ellena, Javier

    2016-08-01

    A comprehensive solid state study of Paroxetine nitrate hydrate, (PRX+·NO3-)H2O, is reported. This salt was characterized by a combination of methods, including Single crystal X-ray diffraction, Thermal analysis, Fourier transform infrared spectroscopy (FTIR) and Solubility measurements. (PRX+·NO3-)H2O crystallizes in the monoclinic C2 space group (Z‧ = 1) and its packing was analyzed in details, showing that the main supramolecular motif consists in a C22(4) chain formed by charge-assisted N+-H⋯O- hydrogen bonds. The salt formation and conformation features were also accuracy established via FTIR spectra. In comparison with the pharmaceutical approved (PRX+ṡCl-)ṡ0.5H2O, (PRX+ṡNO3-)ṡH2O showed a decrease of 24 °C in the drug melting peak and a slight reduction in its water solubility value.

  17. Combining selective sequential extractions, X-Ray Absorption Spectroscopy, and X-Ray Powder Diffraction for Cu (II speciation in soil and mineral phases

    Directory of Open Access Journals (Sweden)

    Tatiana Minkina

    2017-04-01

    Full Text Available Interaction of Cu (II ions with the matrix of soil and mineral phases of layered silicates was assessed by the Miller method of selective sequential fractionation and a set of synchrotron X-ray methods, including X-ray powder diffraction (XRD and X-ray absorption spectroscopy (XANES. It was shown that the input of Cu into Calcic Chernozem in the form of monoxide (CuO and salt (Cu(NO32 affected the transformation of Cu compounds and their affinity for metal-bearing phases. It was found that the contamination of soil with a soluble Cu(II salt increased the bioavailability of the metal and the role of organic matter and Fe oxides in the fixation and retention of Cu. During the incubation of soil with Cu monoxide, the content of the metal in the residual fractions increased, which was related to the possible entry of Cu in the form of isomorphic impurities into silicates, as well as to the incomplete dissolution of exogenic compounds at the high level of their input into the soil. A mechanism for the structural transformation of minerals was revealed, which showed that ion exchange processes result in the sorption of Cu (II ions from the saturated solution by active sites on the internal surface of the lattice of dioctahedral aluminosilicates. Surface hydroxyls at the octahedral aluminum atom play the main role. X-ray diagnostics revealed that excess Cu(II ions are removed from the system due to the formation and precipitation of coarsely crystalline Cu(NO3(OH3.

  18. An X-ray diffraction analysis of oriented lipid multilayers containing basic proteins.

    Science.gov (United States)

    MacNaughtan, W; Snook, K A; Caspi, E; Franks, N P

    1985-08-27

    X-ray diffraction techniques have been used to study the structures of lipid bilayers containing basic proteins. Highly ordered multilayer specimens have been formed by using the Langmuir-Blodgett method in which a solid support is passed through a lipid monolayer held at constant surface pressure at an air/water interface. If the lipid monolayer contains acidic lipids then basic proteins in the aqueous subphase are transferred with the monolayer and incorporated into the multi-membrane stack. X-ray diffraction patterns have been recorded from multilayers of cerebroside sulphate and 40% (molar) cholesterol both with and without polylysine, cytochrome c and the basic protein from central nervous system myelin. Electron density profiles across the membranes have been derived at between 6 A and 12 A resolution. All of the membrane profiles have been placed on an absolute scale of electron density by the isomorphous exchange of cholesterol with a brominated cholesterol analog. The distributions and conformations of the various basic proteins incorporated within the cerebroside sulphate/cholesterol bilayer are very different. Polylysine attaches to the surface of the lipid bilayer as a fully extended chain while cytochrome c maintains its native structure and attaches to the bilayer surface with its short axis approximately perpendicular to the membrane plane. The myelin basic protein associates intimately with the lipid headgroups in the form of an extended molecule, yet its dimension perpendicular to the plane of the membrane of approx. 15 A is consistent with the considerable degree of secondary structure found in solution. In the membrane plane, the myelin basic protein extends to cover an area of about 2500 A2. There is no significant penetration of the protein into the hydrocarbon region of the bilayer or, indeed, beyond the position of the sulphate group of the cerebroside sulphate molecule.

  19. High-resolution X-ray diffraction with no sample preparation.

    Science.gov (United States)

    Hansford, G M; Turner, S M R; Degryse, P; Shortland, A J

    2017-07-01

    It is shown that energy-dispersive X-ray diffraction (EDXRD) implemented in a back-reflection geometry is extremely insensitive to sample morphology and positioning even in a high-resolution configuration. This technique allows high-quality X-ray diffraction analysis of samples that have not been prepared and is therefore completely non-destructive. The experimental technique was implemented on beamline B18 at the Diamond Light Source synchrotron in Oxfordshire, UK. The majority of the experiments in this study were performed with pre-characterized geological materials in order to elucidate the characteristics of this novel technique and to develop the analysis methods. Results are presented that demonstrate phase identification, the derivation of precise unit-cell parameters and extraction of microstructural information on unprepared rock samples and other sample types. A particular highlight was the identification of a specific polytype of a muscovite in an unprepared mica schist sample, avoiding the time-consuming and difficult preparation steps normally required to make this type of identification. The technique was also demonstrated in application to a small number of fossil and archaeological samples. Back-reflection EDXRD implemented in a high-resolution configuration shows great potential in the crystallographic analysis of cultural heritage artefacts for the purposes of scientific research such as provenancing, as well as contributing to the formulation of conservation strategies. Possibilities for moving the technique from the synchrotron into museums are discussed. The avoidance of the need to extract samples from high-value and rare objects is a highly significant advantage, applicable also in other potential research areas such as palaeontology, and the study of meteorites and planetary materials brought to Earth by sample-return missions.

  20. In situ X-ray diffraction measurement of shock-wave-driven twinning and lattice dynamics

    Science.gov (United States)

    Wehrenberg, C. E.; McGonegle, D.; Bolme, C.; Higginbotham, A.; Lazicki, A.; Lee, H. J.; Nagler, B.; Park, H.-S.; Remington, B. A.; Rudd, R. E.; Sliwa, M.; Suggit, M.; Swift, D.; Tavella, F.; Zepeda-Ruiz, L.; Wark, J. S.

    2017-10-01

    Pressure-driven shock waves in solid materials can cause extreme damage and deformation. Understanding this deformation and the associated defects that are created in the material is crucial in the study of a wide range of phenomena, including planetary formation and asteroid impact sites, the formation of interstellar dust clouds, ballistic penetrators, spacecraft shielding and ductility in high-performance ceramics. At the lattice level, the basic mechanisms of plastic deformation are twinning (whereby crystallites with a mirror-image lattice form) and slip (whereby lattice dislocations are generated and move), but determining which of these mechanisms is active during deformation is challenging. Experiments that characterized lattice defects have typically examined the microstructure of samples after deformation, and so are complicated by post-shock annealing and reverberations. In addition, measurements have been limited to relatively modest pressures (less than 100 gigapascals). In situ X-ray diffraction experiments can provide insights into the dynamic behaviour of materials, but have only recently been applied to plasticity during shock compression and have yet to provide detailed insight into competing deformation mechanisms. Here we present X-ray diffraction experiments with femtosecond resolution that capture in situ, lattice-level information on the microstructural processes that drive shock-wave-driven deformation. To demonstrate this method we shock-compress the body-centred-cubic material tantalum—an important material for high-energy-density physics owing to its high shock impedance and high X-ray opacity. Tantalum is also a material for which previous shock compression simulations and experiments have provided conflicting information about the dominant deformation mechanism. Our experiments reveal twinning and related lattice rotation occurring on the timescale of tens of picoseconds. In addition, despite the common association between twinning

  1. In situ X-ray diffraction measurement of shock-wave-driven twinning and lattice dynamics.

    Science.gov (United States)

    Wehrenberg, C E; McGonegle, D; Bolme, C; Higginbotham, A; Lazicki, A; Lee, H J; Nagler, B; Park, H-S; Remington, B A; Rudd, R E; Sliwa, M; Suggit, M; Swift, D; Tavella, F; Zepeda-Ruiz, L; Wark, J S

    2017-10-25

    Pressure-driven shock waves in solid materials can cause extreme damage and deformation. Understanding this deformation and the associated defects that are created in the material is crucial in the study of a wide range of phenomena, including planetary formation and asteroid impact sites, the formation of interstellar dust clouds, ballistic penetrators, spacecraft shielding and ductility in high-performance ceramics. At the lattice level, the basic mechanisms of plastic deformation are twinning (whereby crystallites with a mirror-image lattice form) and slip (whereby lattice dislocations are generated and move), but determining which of these mechanisms is active during deformation is challenging. Experiments that characterized lattice defects have typically examined the microstructure of samples after deformation, and so are complicated by post-shock annealing and reverberations. In addition, measurements have been limited to relatively modest pressures (less than 100 gigapascals). In situ X-ray diffraction experiments can provide insights into the dynamic behaviour of materials, but have only recently been applied to plasticity during shock compression and have yet to provide detailed insight into competing deformation mechanisms. Here we present X-ray diffraction experiments with femtosecond resolution that capture in situ, lattice-level information on the microstructural processes that drive shock-wave-driven deformation. To demonstrate this method we shock-compress the body-centred-cubic material tantalum-an important material for high-energy-density physics owing to its high shock impedance and high X-ray opacity. Tantalum is also a material for which previous shock compression simulations and experiments have provided conflicting information about the dominant deformation mechanism. Our experiments reveal twinning and related lattice rotation occurring on the timescale of tens of picoseconds. In addition, despite the common association between twinning and

  2. Crystallization and X-ray diffraction analysis of human CLEC-2

    Energy Technology Data Exchange (ETDEWEB)

    Watson, Aleksandra A.; O’Callaghan, Christopher A., E-mail: chrisoc@ccmp.ox.ac.uk [Henry Wellcome Building of Molecular Physiology, University of Oxford, Roosevelt Drive, Oxford OX3 7BN (United Kingdom)

    2005-12-01

    Recombinant human CLEC-2 was crystallized in the orthorhombic space group P2{sub 1}2{sub 1}2{sub 1} and X-ray diffraction data were collected to 2.0 Å. The human C-type lectin-like protein CLEC-2 has recently been shown to be expressed on the surface of platelets and to function as a receptor for the snake-venom protein rhodocytin. The C-type lectin-like domain (CTLD) of CLEC-2 was expressed in Escherichia coli, refolded and purified. Crystals of this recombinant CLEC-2 were grown by sitting-drop vapour diffusion using polyethylene glycol (PEG) 6000 as a precipitant. After optimization, crystals were grown which diffracted to 2.0 Å using in-house radiation (λ = 1.5418 Å). These crystals belonged to the orthorhombic space group P2{sub 1}2{sub 1}2{sub 1}, with unit-cell parameters a = 35.407, b = 55.143, c = 56.078 Å. The presence of one molecule per asymmetric unit is consistent with a crystal volume per unit weight (V{sub M}) of 1.82 Å{sup 3} Da{sup −1} and a solvent content of 32.6%. These results suggest that crystals producing diffraction of this quality will be suitable for the structural determination of human CLEC-2.

  3. About some practical aspects of X-ray diffraction : From powder to thin film

    Energy Technology Data Exchange (ETDEWEB)

    Valvoda, V. [Charles Univ. Prague (Czech Republic). Faculty of Mathematics and Physics

    1996-09-01

    Structure of thin films can be amorphous, polycrystalline or epitaxial, and the films can be prepared as a single layer films, multilayers or as graded films. A complete structure analysis of thin films by means of X-ray diffraction (XRD) usually needs more than one diffraction geometry to be used. Their principles, advantages and disadvantages will be shortly described, especially with respect to their different sampling depth and different response to orientation of diffracting crystallographic planes. Main differences in structure of thin films with respect to powder samples are given by a singular direction of their growth, by their adhesion to a substrate and often also by a simultaneous bombardment by atomic species during the growth. It means that a thermodynamically unstable atomic structures can be found too. These special features of growth of thin polycrystalline films are reflected in often found strong preferred orientation of grains and in residual stresses conserved in the films. The methods of structure analysis of thin films by XRD will be compared with other techniques which can supply structure images on different scales.

  4. Crystallization and X-ray diffraction analysis of a catalytic domain of hyperthermophilic chitinase from Pyrococcus furiosus

    Energy Technology Data Exchange (ETDEWEB)

    Mine, Shouhei; Nakamura, Tsutomu [National Institute of Advanced Industrial Science and Technology (AIST), 1-8-31 Midorigaoka, Ikeda, Osaka 563-8577 (Japan); Hirata, Kunio [RIKEN/SPring-8, Kouto 1-1-1, Sayo-cho, Sayo-gun, Hyogo 679-5148 (Japan); Ishikawa, Kazuhiko; Hagihara, Yoshihisa; Uegaki, Koichi, E-mail: k-uegaki@aist.go.jp [National Institute of Advanced Industrial Science and Technology (AIST), 1-8-31 Midorigaoka, Ikeda, Osaka 563-8577 (Japan)

    2006-08-01

    The expression, purification and preliminary X-ray diffraction analysis of a catalytic domain of a chitinase from P. furiosus is reported. The crystallization and preliminary X-ray diffraction analysis of a catalytic domain of chitinase (PF1233 gene) from the hyperthermophilic archaeon Pyrococcus furiosus is reported. The recombinant protein, prepared using an Escherichia coli expression system, was crystallized by the hanging-drop vapour-diffusion method. An X-ray diffraction data set was collected at the undulator beamline BL44XU at SPring-8 to a resolution of 1.50 Å. The crystals belong to space group P2{sub 1}2{sub 1}2{sub 1}, with unit-cell parameters a = 90.0, b = 92.8, c = 107.2 Å.

  5. Crystallization and preliminary X-ray diffraction analysis of a chitin-binding domain of hyperthermophilic chitinase from Pyrococcus furiosus

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, Tsutomu; Ishikawa, Kazuhiko; Hagihara, Yoshihisa; Oku, Takashi [National Institute of Advanced Industrial Science and Technology (AIST), 1-8-31 Midorigaoka, Ikeda, Osaka 563-8577 (Japan); Nakagawa, Atsushi [Institute for Protein Research, Osaka University, 3-2 Yamadaoka, Suita, Osaka 565-0871 (Japan); Inoue, Tsuyoshi [Department of Materials Chemistry, Graduate School of Engineering, Osaka University, 3-2 Yamadaoka, Suita, Osaka 565-0871 (Japan); Ataka, Mitsuo; Uegaki, Koichi, E-mail: k-uegaki@aist.go.jp [National Institute of Advanced Industrial Science and Technology (AIST), 1-8-31 Midorigaoka, Ikeda, Osaka 563-8577 (Japan)

    2005-05-01

    The expression, purification and preliminary X-ray diffraction studies of a chitin-binding domain of the chitinase from P. furiosus are reported. The crystallization and preliminary X-ray diffraction analysis of the chitin-binding domain of chitinase from a hyperthermophilic archaeon, Pyrococcus furiosus, are reported. The recombinant protein was prepared using an Escherichia coli overexpression system and was crystallized by the hanging-drop vapour-diffusion method. An X-ray diffraction data set was collected to 1.70 Å resolution. The crystal belonged to space group P4{sub 3}2{sub 1}2 or P4{sub 1}2{sub 1}2. The unit-cell parameters were determined to be a = b = 48.8, c = 85.0 Å.

  6. Tuning of colossal dielectric constant in gold-polypyrrole composite nanotubes using in-situ x-ray diffraction techniques

    Directory of Open Access Journals (Sweden)

    Abhisakh Sarma

    2014-09-01

    Full Text Available In-situ x-ray diffraction technique has been used to study the growth process of gold incorporated polypyrrole nanotubes that exhibit colossal dielectric constant due to existence of quasi-one-dimensional charge density wave state. These composite nanotubes were formed within nanopores of a polycarbonate membrane by flowing pyrrole monomer from one side and mixture of ferric chloride and chloroauric acid from other side in a sample cell that allows collection of x-ray data during the reaction. The size of the gold nanoparticle embedded in the walls of the nanotubes was found to be dependent on chloroauric acid concentration for nanowires having diameter more than 100 nm. For lower diameter nanotubes the nanoparticle size become independent of chloroauric acid concentration and depends on the diameter of nanotubes only. The result of this study also shows that for 50 nm gold-polypyrrole composite nanotubes obtained with 5.3 mM chloroauric acid gives colossal dielectric constant of about 107. This value remain almost constant over a frequency range from 1Hz to 106 Hz even at 80 K temperature.

  7. Tuning of colossal dielectric constant in gold-polypyrrole composite nanotubes using in-situ x-ray diffraction techniques

    Energy Technology Data Exchange (ETDEWEB)

    Sarma, Abhisakh; Sanyal, Milan K., E-mail: milank.sanyal@saha.ac.in [Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata 700 064 (India)

    2014-09-15

    In-situ x-ray diffraction technique has been used to study the growth process of gold incorporated polypyrrole nanotubes that exhibit colossal dielectric constant due to existence of quasi-one-dimensional charge density wave state. These composite nanotubes were formed within nanopores of a polycarbonate membrane by flowing pyrrole monomer from one side and mixture of ferric chloride and chloroauric acid from other side in a sample cell that allows collection of x-ray data during the reaction. The size of the gold nanoparticle embedded in the walls of the nanotubes was found to be dependent on chloroauric acid concentration for nanowires having diameter more than 100 nm. For lower diameter nanotubes the nanoparticle size become independent of chloroauric acid concentration and depends on the diameter of nanotubes only. The result of this study also shows that for 50 nm gold-polypyrrole composite nanotubes obtained with 5.3 mM chloroauric acid gives colossal dielectric constant of about 10{sup 7}. This value remain almost constant over a frequency range from 1Hz to 10{sup 6} Hz even at 80 K temperature.

  8. Characterization of Precipitates in a Microalloyed Steel Using Quantitative X-ray Diffraction

    Directory of Open Access Journals (Sweden)

    J. Barry Wiskel

    2016-04-01

    Full Text Available Quantitative X-ray diffraction (QXRD (also known as the Rietveld method was used to analyze the precipitates present in Grade 100 microalloyed steel. The precipitates were extracted from the steel using electrolytic dissolution and the residue from the dissolution was analyzed using XRD. The XRD pattern exhibited three (3 distinct diffraction peaks, and significant broadening of a fourth peak corresponding to the <10 nm size precipitates. QXRD analysis was applied to the XRD pattern to obtain precipitate size, composition, and weight fraction data for each of the four diffraction peaks observed. The predicted mean precipitate diameter and average atomic composition of the nano-size (<10 nm precipitates was 4.7 nm and (Nb0.50Ti0.32Mo0.18(C0.59N0.41, respectively. The predicted precipitate size correlates well with the average size of precipitates measured in previous work by the authors using both transmission electron microscopy (TEM and small angle neutron scattering (SANS. The average atomic composition correlates well with the composition measured in this work using energy dispersive X-ray (EDX analysis of individual nano-sized precipitates. The calculated weight fraction of the nano-size precipitates in the extracted residue was 42.2 wt. %. The calculated atomic compositions of the other three diffraction peaks were TiN, (Ti0.87Nb0.13N, and (Nb0.82Ti0.18(C0.87N0.13 with weight fraction values of 12.9 wt. %, 31.7 wt. %, and 13.1 wt. %, respectively. The sizes of both the (Ti0.87Nb0.13N and the (Nb0.82Ti0.18(C0.87N0.13 groups of precipitates were directly measured and were observed to range from 150 nm to 570 nm and from 90 nm to 475 nm, respectively. QXRD was unable to determine a reasonable mean precipitate size for either of these two groups of precipitates. The wide compositional range (i.e., varying levels of Nb and Ti of these precipitates (as measured by EDX resulted in XRD peak broadening that was erroneously interpreted as a size

  9. Cross-sectional X-ray nanobeam diffraction analysis of a compositionally graded CrN{sub x} thin film

    Energy Technology Data Exchange (ETDEWEB)

    Bartosik, M., E-mail: matthias.bartosik@tuwien.ac.at [Department of Materials Physics, Montanuniversität Leoben and Erich Schmid Institute of Materials Science, Austrian Academy of Sciences (Austria); Christian Doppler Laboratory for Application Oriented Coating Development, Montanuniversitat Leoben and Vienna University of Technology (Austria); Daniel, R.; Mitterer, C. [Department of Physical Metallurgy and Materials Testing, Montanuniversität Leoben (Austria); Matko, I. [Institute of Physics, Slovak Academy of Sciences, Bratislava (Slovakia); Burghammer, M. [European Synchrotron Radiation Facility, Grenoble (France); Mayrhofer, P.H. [Christian Doppler Laboratory for Application Oriented Coating Development, Montanuniversitat Leoben and Vienna University of Technology (Austria); Institute of Materials Science and Technology, Vienna University of Technology (Austria); Keckes, J. [Department of Materials Physics, Montanuniversität Leoben and Erich Schmid Institute of Materials Science, Austrian Academy of Sciences (Austria); Materials Center Leoben GmbH, Leoben (Austria)

    2013-09-02

    Synchrotron X-ray nanodiffraction is used for the position-resolved characterization of a nanocrystalline graded CrN{sub x} thin film deposited with continuously increasing nitrogen content over the 6 μm film thickness. The diffraction experiment is performed in wide angle X-ray scattering transmission geometry using a monochromatic beam of 100 nm in diameter. The results reveal a complex microstructure and texture evolution in hexagonal Cr{sub 2}N and cubic CrN{sub x} phases as well as a compressive strain increase in CrN{sub x} towards the film surface. - Highlights: • Cross-sectional X-ray nanodiffraction analysis of a graded thin film • Position-resolved characterization of microstructure, strain and phases • Comparison of cross-sectional TEM and X-ray nanodiffraction.

  10. In situ x-ray diffraction of solution-derived ferroelectric thin films for quantitative phase and texture evolution measurement

    Science.gov (United States)

    Nittala, Krishna; Mhin, Sungwook; Jones, Jacob L.; Robinson, Douglas S.; Ihlefeld, Jon F.; Brennecka, Geoff L.

    2012-11-01

    An in situ measurement technique is developed and presented, which utilizes x-rays from a synchrotron source with a two-dimensional detector to measure thin film microstructural and crystallographic evolution during heating. A demonstration experiment is also shown wherein the measured diffraction patterns are used to describe phase and texture evolution during heating and crystallization of solution-derived thin films. The diffraction images are measured sequentially while heating the thin film with an infrared lamp. Data reduction methodologies and representations are also outlined to extract phase and texture information from the diffraction images as a function of time and temperature. These techniques and data reduction methods are demonstrated during crystallization of solution-derived lead zirconate titanate ferroelectric thin films heated at a rate of 30 °C/min and using an acquisition time of 8 s. During heating and crystallization, a PtxPb type phase was not observed. A pyrochlore phase was observed prior to the formation and growth of the perovskite phase. The final crystallized films are observed to have both 111 and 100 texture components. The in situ measurement methodology developed in this work allows for acquiring diffraction images in times as low as 0.25 s and can be used to investigate changes during crystallization at faster heating rates. Moreover, the experiments are shown to provide unique information during materials processing.

  11. Characterization of mineral phases of agricultural soil samples of Colombian coffee using Moessbauer spectroscopy and X-ray diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez, Humberto Bustos, E-mail: hbustos@ut.edu.co; Lozano, Dagoberto Oyola; Martinez, Yebrayl Antonio Rojas; Pinilla, Marlene Rivera [Universidad del Tolima, Grupo Ciencia de Materiales y Tecnologia en Plasma (Colombia); Alcazar, German Antonio Perez [Universidad del Valle, Grupo Metalurgia Fisica y Teoria de las Transiciones de Fase (Colombia)

    2012-03-15

    Soil chemical analysis, X-ray diffraction (XRD) and Moessbauer spectrometry (MS) of {sup 57}Fe were used to characterize mineral phases of samples taken from the productive layer (horizon A) of agricultural coffee soil from Tolima (Colombia). Chemical analysis shows the chemical and textural parameters of samples from two different regions of Tolima, i.e., Ibague and Santa Isabel. By XRD phases like illite (I), andesine (A) and quartz (Q) in both samples were identified. The quantity of these phases is different for the two samples. The MS spectra taken at room temperature were adjusted by using five doublets, three of them associated to Fe{sup + 3} type sites and the other two to Fe{sup + 2} type sites. According to their isomer shift and quadrupole splitting the presence of phases like illite (detected by DRX), nontronite and biotite (not detected by XRD) can be postulated.

  12. Synchrotron X-ray powder diffraction studies on the order-disorder phase transition in lithium ferrites

    Energy Technology Data Exchange (ETDEWEB)

    Darul, J. [Laboratory of Magnetochemistry, Faculty of Chemistry, Adam Mickiewicz University, Grunwaldzka 6, PL-60780 Poznan (Poland)]. E-mail: jola@amu.edu.pl; Nowicki, W. [Laboratory of Magnetochemistry, Faculty of Chemistry, Adam Mickiewicz University, Grunwaldzka 6, PL-60780 Poznan (Poland); Piszora, P. [Laboratory of Magnetochemistry, Faculty of Chemistry, Adam Mickiewicz University, Grunwaldzka 6, PL-60780 Poznan (Poland); Baehtz, C. [Institute of Materials Science, Darmstadt University of Technology, Petersenstr. 32, D-64287 Darmstadt (Germany); Wolska, E. [Laboratory of Magnetochemistry, Faculty of Chemistry, Adam Mickiewicz University, Grunwaldzka 6, PL-60780 Poznan (Poland)

    2005-09-29

    Investigations on the manganese substituted lithium ferrites reveal the strong influence of manganese ions on the ordering of Li{sup +} cations in the spinel-type crystal lattice. We present the effect of Mn{sup 3+} substitution in the LiFe{sub 5-x}Mn {sub x}O{sub 8} (0 {<=} x {<=} 1) samples on the order-disorder phase transition and on the thermal expansion of their spinel lattices. Synchrotron X-ray measurements have been performed in the temperature range 10-300 K and 300-1173 K. The diffraction experiments were carried out at the DESY-HASYLAB high-resolution powder diffractometer (beamline B2). The transition from ordered (cubic primitive, P4 {sub 1} 32) to disordered (face centred cubic, Fd3m) structure was observed with the increasing Mn{sup 3+} content.

  13. X-Ray diffraction technique applied to study of residual stresses after welding of duplex stainless steel plates

    Energy Technology Data Exchange (ETDEWEB)

    Monin, Vladimir Ivanovitch; Assis, Joaquim Teixeira de [Instituto Politecnico do Rio e Janeiro (IPRJ), Nova Friburgo, RJ (Brazil); Lopes, Ricardo Tadeu; Turibus, Sergio Noleto; Payao Filho, Joao C., E-mail: sturibus@nuclear.ufrj.br [Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ (Brazil)

    2014-08-15

    Duplex stainless steel is an example of composite material with approximately equal amounts of austenite and ferrite phases. Difference of physical and mechanical properties of component is additional factor that contributes appearance of residual stresses after welding of duplex steel plates. Measurements of stress distributions in weld region were made by X-ray diffraction method both in ferrite and austenite phases. Duplex Steel plates were joined by GTAW (Gas Tungsten Arc Welding) technology. There were studied longitudinal and transverse stress components in welded butt joint, in heat affected zone (HAZ) and in points of base metal 10 mm from the weld. Residual stresses measured in duplex steel plates jointed by welding are caused by temperature gradients between weld zone and base metal and by difference of thermal expansion coefficients of ferrite and austenite phases. Proposed analytical model allows evaluating of residual stress distribution over the cross section in the weld region. (author)

  14. A flow cell for the study of gas-solid reactions via in situ powder X-ray diffraction

    Science.gov (United States)

    Scarlett, Nicola V. Y.; Hewish, Damien; Pattel, Rachel; Webster, Nathan A. S.

    2017-10-01

    This paper describes the development and testing of a novel capillary flow cell for use in in situ powder X-ray diffraction experiments. It is designed such that it achieves 200° of rotation of the capillary whilst still allowing the flow of gas through the sample and the monitoring of off gas via mass spectrometry, gas chromatography, or other such analytical techniques. This high degree of rotation provides more uniform heating of the sample than can be achieved in static cells or those with lower rotational ranges and consequently also improves particle statistics. The increased uniformity of heating provides more accurate temperature calibration of the experimental setup as well. The cell is designed to be held in a standard goniometer head and is therefore suitable for use in many laboratory and synchrotron instruments.

  15. Humidity control and hydrophilic glue coating applied to mounted protein crystals improves X-ray diffraction experiments

    Science.gov (United States)

    Baba, Seiki; Hoshino, Takeshi; Ito, Len; Kumasaka, Takashi

    2013-01-01

    Protein crystals are fragile, and it is sometimes difficult to find conditions suitable for handling and cryocooling the crystals before conducting X-ray diffraction experiments. To overcome this issue, a protein crystal-mounting method has been developed that involves a water-soluble polymer and controlled humid air that can adjust the moisture content of a mounted crystal. By coating crystals with polymer glue and exposing them to controlled humid air, the crystals were stable at room temperature and were cryocooled under optimized humidity. Moreover, the glue-coated crystals reproducibly showed gradual transformations of their lattice constants in response to a change in humidity; thus, using this method, a series of isomorphous crystals can be prepared. This technique is valuable when working on fragile protein crystals, including membrane proteins, and will also be useful for multi-crystal data collection. PMID:23999307

  16. Synthesis and single crystal x-ray diffraction study of a Schiff base derived from 4-acylpyrazolone and 2-aminophenol

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, Naresh; Kant, Rajni, E-mail: vivek-gupta2k2@hotmail.com; Gupta, Vivek K., E-mail: vivek-gupta2k2@hotmail.com [Department of Physics and Electronics, University of Jammu, Jammu Tawi - 180006 (India); Jadeja, R. N. [Department of Chemistry, Faculty of Science, The M. S. University of Baroda, Vadodara-390002 (India)

    2014-04-24

    The title compound, (Z)-1-(3-chlorophenyl)-4[1((2hydroxyphenyl)amino)propylidene] -3-methyl-1H-pyrazol-5(4H)-one was synthesized by refluxing compound 1-(m-chlorophenyl)-3-methyl-4-propionyl-5-pyrazolone, with 2-aminophenol in ethanol. The compound crystallizes in the orthorhombic crystal system with space group Pca2{sub 1} having unit cell parameters: a = 26.2993(8), b = 7.0724(2) and c = 18.7170(5)Å. The structure contains two crystallographically independent molecules, A, and, B, in the asymmetric unit cell. The crystal structure was solved by direct method using single crystal X-ray diffraction data collected at room temperature and refined by full-matrix least-squares procedures to a final R- value of 0.049 for 5207 observed reflections.

  17. X-ray microstructural analysis of nanocrystalline TiZrN thin films by diffraction pattern modeling

    Energy Technology Data Exchange (ETDEWEB)

    Escobar, D. [Laboratorio de Física del Plasma, Universidad Nacional de Colombia Sede Manizales, Km. 9 Vía al Magdalena, Manizales (Colombia); PCM Computacional Applications, Universidad Nacional de Colombia Sede Manizales, Km. 9 Vía al Magdalena, Manizales (Colombia); Ospina, R. [Laboratorio de Física del Plasma, Universidad Nacional de Colombia Sede Manizales, Km. 9 Vía al Magdalena, Manizales (Colombia); Gómez, A.G. [Pontificia Universidad Javeriana Seccional Cali, Facultad de Ingeniería, Departamento de Ciencias de la Ingeniería y la Producción (Colombia); Restrepo-Parra, E., E-mail: erestrepopa@unal.edu.co [Laboratorio de Física del Plasma, Universidad Nacional de Colombia Sede Manizales, Km. 9 Vía al Magdalena, Manizales (Colombia); PCM Computacional Applications, Universidad Nacional de Colombia Sede Manizales, Km. 9 Vía al Magdalena, Manizales (Colombia); Arango, P.J. [Laboratorio de Física del Plasma, Universidad Nacional de Colombia Sede Manizales, Km. 9 Vía al Magdalena, Manizales (Colombia)

    2014-02-15

    A detailed microstructural characterization of nanocrystalline TiZrN thin films grown at different substrate temperatures (T{sub S}) was carried out by X-ray diffraction (XRD). Total diffraction pattern modeling based on more meaningful microstructural parameters, such as crystallite size distribution and dislocation density, was performed to describe the microstructure of the thin films more precisely. This diffraction modeling has been implemented and used mostly to characterize powders, but the technique can be very useful to study hard thin films by taking certain considerations into account. Nanocrystalline films were grown by using the cathodic pulsed vacuum arc technique on stainless steel 316L substrates, varying the temperature from room temperature to 200 °C. Further surface morphology analysis was performed to study the dependence of grain size on substrate temperature using atomic force microscopy (AFM). The crystallite and surface grain sizes obtained and the high density of dislocations observed indicate that the films underwent nanostructured growth. Variations in these microstructural parameters as a function of T{sub S} during deposition revealed a competition between adatom mobility and desorption processes, resulting in a specific microstructure. These films also showed slight anisotropy in their microstructure, and this was incorporated into the diffraction pattern modeling. The resulting model allowed for the films' microstructure during synthesis to be better understood according to the experimental results obtained. - Highlights: • Mobility and desorption competition generates a critical temperature. • A microstructure anisotropy related to the local strain was observed in thin films. • Adatom mobility and desorption influence grain size and microstrain.

  18. Natural and synthetic prion structure from X-ray fiber diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Wille, Holger; Bian, Wen; McDonald, Michele; Kendall, Amy; Colby, David W.; Bloch, Lillian; Ollesch, Julian; Borovinskiy, Alexander L.; Cohen, Fred E.; Prusiner, Stanley B.; Stubbs, Gerald; (Vanderbilt); (UCSF)

    2009-10-21

    A conformational isoform of the mammalian prion protein (PrP{sup Sc}) is the sole component of the infectious pathogen that causes the prion diseases. We have obtained X-ray fiber diffraction patterns from infectious prions that show cross-{beta} diffraction: meridional intensity at 4.8 {angstrom} resolution, indicating the presence of {beta} strands running approximately at right angles to the filament axis and characteristic of amyloid structure. Some of the patterns also indicated the presence of a repeating unit along the fiber axis, corresponding to four {beta}-strands. We found that recombinant (rec) PrP amyloid differs substantially from highly infectious brain-derived prions, both in structure as demonstrated by the diffraction data, and in heterogeneity as shown by electron microscopy. In addition to the strong 4.8 {angstrom} meridional reflection, the recPrP amyloid diffraction is characterized by strong equatorial intensity at approximately 10.5 {angstrom}, absent from brain-derived prions, and indicating the presence of stacked {beta}-sheets. Synthetic prions recovered from transgenic mice inoculated with recPrP amyloid displayed structural characteristics and homogeneity similar to those of naturally occurring prions. The relationship between the structural differences and prion infectivity is uncertain, but might be explained by any of several hypotheses: only a minority of recPrP amyloid possesses a replication-competent conformation, the majority of recPrP amyloid has to undergo a conformational maturation to acquire replication competency, or inhibitory forms of recPrP amyloid interfere with replication during the initial transmission.

  19. Expression, crystallization and preliminary X-ray diffraction studies of recombinant Clostridium perfringens β2-toxin

    Energy Technology Data Exchange (ETDEWEB)

    Gurjar, Abhijit A. [Department of Veterinary and Biomedical Science, The Pennsylvania State University (United States); Yennawar, Neela H.; Yennawar, Hemant P. [Macromolecular X-ray Crystallography Facility, The Pennsylvania State University (United States); Rajashankar, Kanagalaghatta R. [Argonne National Laboratory (United States); Hegde, Narasimha V.; Jayarao, Bhushan M., E-mail: bmj3@psu.edu [Department of Veterinary and Biomedical Science, The Pennsylvania State University (United States)

    2007-06-01

    The cloning, expression, purification and crystallization of recombinant Clostridium perfringens β2-toxin is described. The crystals diffracted to 2.9 Å resolution. Clostridium perfringens is a Gram-positive sporulating anaerobic bacterium that is responsible for a wide spectrum of diseases in animals, birds and humans. The virulence of C. perfringens is associated with the production of several enterotoxins and exotoxins. β2-toxin is a 28 kDa exotoxin produced by C. perfringens. It is implicated in necrotic enteritis in animals and humans, a disease characterized by a sudden acute onset with lethal hemorrhagic mucosal ulceration. The recombinant expression, purification and crystallization of β2-toxin using the batch-under-oil technique are reported here. Native X-ray diffraction data were obtained to 2.9 Å resolution on a synchrotron beamline at the F2 station at Cornell High Energy Synchrotron Source (CHESS) using an ADSC Quantum-210 CCD detector. The crystals belong to space group R3, with a dimer in the asymmetric unit; the unit-cell parameters are a = b = 103.71, c = 193.48 Å, α = β = 90, γ = 120° using the hexagonal axis setting. A self-rotation function shows that the two molecules are related by a noncrystallographic twofold axis with polar angles ω = 90.0, ϕ = 210.3°.

  20. Crystallization and X-ray diffraction studies of cellobiose phosphorylase from Cellulomonas uda.

    Science.gov (United States)

    Van Hoorebeke, Annelies; Stout, Jan; Kyndt, John; De Groeve, Manu; Dix, Ina; Desmet, Tom; Soetaert, Wim; Van Beeumen, Jozef; Savvides, Savvas N

    2010-03-01

    Disaccharide phosphorylases are able to catalyze both the synthesis and the breakdown of disaccharides and have thus emerged as attractive platforms for tailor-made sugar synthesis. Cellobiose phosphorylase from Cellulomonas uda (CPCuda) is an enzyme that belongs to glycoside hydrolase family 94 and catalyzes the reversible breakdown of cellobiose [beta-D-glucopyranosyl-(1,4)-D-glucopyranose] to alpha-D-glucose-1-phosphate and D-glucose. Crystals of ligand-free recombinant CPCuda and of its complexes with substrates and reaction products yielded complete X-ray diffraction data sets to high resolution using synchrotron radiation but suffered from significant variability in diffraction quality. In at least one case an intriguing space-group transition from a primitive monoclinic to a primitive orthorhombic lattice was observed during data collection. The structure of CPCuda was determined by maximum-likelihood molecular replacement, thus establishing a starting point for an investigation of the structural and mechanistic determinants of disaccharide phosphorylase activity.

  1. Single crystal X-ray diffraction studies of DNA and DNA-drug complexes

    CERN Document Server

    Todd, A K

    1999-01-01

    The structure of the brominated oligonucleotide d(ACGTACG(5-BrU)) sub 2 was solved using the multiwavelength anomalous diffraction (MAD) technique. The space group was P4 sub 3 2 sub 1 2, with unit cell a=b=43.60A, c=26.27A. This structure was an A-DNA, isomorphous with many other previously solved octomers. Single crystal X-ray diffraction data were collected from crystals of the intercalation complexes N-[2-(dimethylamino)ethyl] acridine-4-carboxamide (DACA), d(CGTACG) sub 2 and N-[2-(dimethylamino)ethyl] 9-aminoacridine-4-carboxamide (9- aminoDACA) and some of their derivatives. An attempt was made to solve the structure of the DACA derivative N-[2-(dimethylamino)butyl]-acridine-4-carboxamide (DACA4) by molecular replacement, using the crystal structure of the daunomycin d(CGTACG) sub 2 complex as a search model. Attempts were made to position the molecule in the unit cell based on an SIR map, knowledge of the symmetry and unit cell dimensions. The structure of the 9-amino-5-bromo DACA - d(CGT(5-BrU)CG) su...

  2. Fundamental Limits on Spatial Resolution in Ultrafast X-ray Diffraction

    Directory of Open Access Journals (Sweden)

    Adam Kirrander

    2017-05-01

    Full Text Available X-ray Free-Electron Lasers have made it possible to record time-sequences of diffraction images to determine changes in molecular geometry during ultrafast photochemical processes. Using state-of-the-art simulations in three molecules (deuterium, ethylene, and 1,3-cyclohexadiene, we demonstrate that the nature of the nuclear wavepacket initially prepared by the pump laser, and its subsequent dispersion as it propagates along the reaction path, limits the spatial resolution attainable in a structural dynamics experiment. The delocalization of the wavepacket leads to a pronounced damping of the diffraction signal at large values of the momentum transfer vector q, an observation supported by a simple analytical model. This suggests that high-q measurements, beyond 10–15 Å − 1 , provide scant experimental payback, and that it may be advantageous to prioritize the signal-to-noise ratio and the time-resolution of the experiment as determined by parameters such as the repetition-rate, the photon flux, and the pulse durations. We expect these considerations to influence future experimental designs, including source development and detection schemes.

  3. Fast X-ray powder diffraction on I11 at Diamond.

    Science.gov (United States)

    Thompson, Stephen P; Parker, Julia E; Marchal, Julien; Potter, Jonathan; Birt, Adrian; Yuan, Fajin; Fearn, Richard D; Lennie, Alistair R; Street, Steven R; Tang, Chiu C

    2011-07-01

    The commissioning and performance characterization of a position-sensitive detector designed for fast X-ray powder diffraction experiments on beamline I11 at Diamond Light Source are described. The detecting elements comprise 18 detector-readout modules of MYTHEN-II silicon strip technology tiled to provide 90° coverage in 2θ. The modules are located in a rigid housing custom designed at Diamond with control of the device fully integrated into the beamline data acquisition environment. The detector is mounted on the I11 three-circle powder diffractometer to provide an intrinsic resolution of Δ2θ approximately equal to 0.004°. The results of commissioning and performance measurements using reference samples (Si and AgI) are presented, along with new results from scientific experiments selected to demonstrate the suitability of this facility for powder diffraction experiments where conventional angle scanning is too slow to capture rapid structural changes. The real-time dehydrogenation of MgH(2), a potential hydrogen storage compound, is investigated along with ultrafast high-throughput measurements to determine the crystallite quality of different samples of the metastable carbonate phase vaterite (CaCO(3)) precipitated and stabilized in the presence of amino acid molecules in a biomimetic synthesis process.

  4. Analysis of the corium phases by X-ray diffraction; Analyses des phases du corium par diffraction des rayons X

    Energy Technology Data Exchange (ETDEWEB)

    Trillon, G

    2004-07-01

    In the framework of the severe accidents R and D studies led by CEA, the better knowledge of the corium behaviour, corium coming from the melting of a nuclear reactor, are fundamental stakes in order to master this kind of accident. Among the available physical properties of the corium, the nature of the final crystalline compounds which have been made during the, cooling gives information about its solidification and its stabilisation. X-Rays Diffraction is the reference method used in order to characterize the corium coming from the different facilities of the European platform PLINIUS of CEA-Cadarache. This work presents the scientific approach that has been followed in order to obtain information both qualitative and quantitative on corium, using X-Rays Diffraction. For instance, a specific method for identifying U{sub 1-x}Zr{sub x}O{sub 2} solid solutions has been developed, and the validity of quantitative analysis of corium crystalline phases using the Rietveld method (with an internal standard), has been tested. This last method has also permitted semi-quantitative measurements of amorphous phases within corium. For these studies, analysis of prototypical corium has been conducted on samples coming from the experiences led on the different facilities of the PLINIUS platform. These analysis allowed for the first time to obtain quantitative data of the corium crystalline phases in order to validate thermodynamic databases and has been used to estimate the thereto-physical properties of the corium. New information on crystalline phases of corium has also been found, especially for the UO{sub 2}-ZrO{sub 2} pseudo binary system. (author)

  5. Assessment of firing conditions in old fired-clay bricks. The contribution of X-ray powder diffraction with the Rietveld method and small angle neutron scattering

    Czech Academy of Sciences Publication Activity Database

    Viani, Alberto; Sotiriadis, Konstantinos; Len, A.; Šašek, Petr; Ševčík, Radek

    2016-01-01

    Roč. 116, June (2016), s. 33-43 ISSN 1044-5803 R&D Projects: GA MŠk(CZ) LO1219 Keywords : fired- clay brick * Rietveld method * small angle neutron scattering * X-ray diffraction * firing temperature Subject RIV: AL - Art, Architecture, Cultural Heritage Impact factor: 2.714, year: 2016 http://www.sciencedirect.com/science/article/pii/S1044580316300870

  6. Effect of C16TMA contents on the thermal stability of organo-bentonites: In situ X-ray diffraction analysis

    Energy Technology Data Exchange (ETDEWEB)

    Kooli, Fethi, E-mail: fkooli@taibahu.edu.sa [Taibah University, Department of Chemistry, PO Box 30002, Al-Madinah Al-Munawwarah (Saudi Arabia)

    2013-01-10

    Highlights: Black-Right-Pointing-Pointer Organo-bentonites were prepared at C16TMABr/CEC ratios up to 11. Black-Right-Pointing-Pointer Disorder configuration of C16TMA cations was observed at higher C16TMABr/CEC ratios. Black-Right-Pointing-Pointer The evolved gases during the calcinations of organoclays were analyzed by MS-TG. Black-Right-Pointing-Pointer In situ XRD technique detected clearly the phase disorder in the range 50-150 Degree-Sign C. Black-Right-Pointing-Pointer Collapse of organoclays depended on the temperature and the used atmospheres. - Abstract: Different concentrations of cetyl trimethylammonium bromide solutions were cation exchanged with bentonite clay mineral, at room temperature. The resulting organoclays were characterized by elemental analysis C and N, X-ray diffraction and thermal gravimetric analysis. The evolved gases during the calcination of organoclays were identified by online mass spectrometry coupled with thermal gravimetry technique. Meanwhile, in situ X-ray diffraction was used to have insight on the thermal stability of the organoclays in air atmosphere. X-ray diffraction at room temperature indicated that a disorder transition phase from bilayer to paraffin configuration occurred at higher surfactant-cation exchange capacity ratios, with two phases at 3.25 and 2.00 nm, respectively. The in situ X-ray diffraction confirmed the presence of these two phases with improved reflections intensities in the range of 100-200 Degree-Sign C. Above this temperature, both phases collapsed due to the decomposition of the surfactants as recorded by mass spectrometry thermal gravimetric analysis.

  7. Structure of Calcium Aluminate Decahydrate (CaAl2O4.10D2O) from Neutron and X-ray Powder Diffraction Data

    Energy Technology Data Exchange (ETDEWEB)

    Christensen,A.; Lebech, B.; Sheptyakov, D.; Hanson, J.

    2007-01-01

    Calcium aluminate decahydrate is hexagonal with the space group P63/m and Z = 6. The compound has been named CaAl2O4{center_dot}10H2O (CAH10) for decades and is known as the product obtained by hydration of CaAl2O4 (CA) in the temperature region 273-288 K - one of the main components in high-alumina cements. The lattice constants depend on the water content. Several sample preparations were used in this investigation: one CAH10, three CAD10 and one CA(D/H)10, where the latter is a zero-matrix sample showing no coherent scattering contribution from the D/H atoms in a neutron diffraction powder pattern. The crystal structure including the positions of the H/D atoms was determined from analyses of four neutron diffraction powder patterns by means of the ab initio crystal structure determination program FOX and the FULLPROF crystal structure refinement program. Additionally, eight X-ray powder diffraction patterns (Cu K[alpha]1 and synchrotron X-rays) were used to establish phase purity. The analyses of these combined neutron and X-ray diffraction data clearly show that the previously published positions of the O atoms in the water molecules are in error. Thermogravimetric analysis of the CAD10 sample preparation used for the neutron diffraction studies gave the composition CaAl2(OD)8(D2O)2{center_dot}2.42D2O. Neutron and X-ray powder diffraction data gave the structural formula CaAl2(OX)8(X2O)2{center_dot}[gamma]X2O (X = D, H and D/H), where the [gamma] values are sample dependent and lie between 2.3 and 3.3.

  8. Densitometry and temperature measurement of combustion gas by X-ray Compton scattering

    Energy Technology Data Exchange (ETDEWEB)

    Sakurai, Hiroshi, E-mail: sakuraih@gunma-u.ac.jp [Gunma University, 1-5-1 Tenjin-cho, Kiryu, Gunma 376-8515 (Japan); Kawahara, Nobuyuki [Okayama University, Tsushima-Naka 3, Okayama 700-8530 (Japan); Itou, Masayoshi [Japan Synchrotron Radiation Research Institute (JASRI), 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5198 (Japan); Tomita, Eiji [Okayama University, Tsushima-Naka 3, Okayama 700-8530 (Japan); Suzuki, Kosuke [Gunma University, 1-5-1 Tenjin-cho, Kiryu, Gunma 376-8515 (Japan); Sakurai, Yoshiharu [Japan Synchrotron Radiation Research Institute (JASRI), 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5198 (Japan)

    2016-02-17

    Measurement of combustion gas by high-energy X-ray Compton scattering is reported. Measurement of combustion gas by high-energy X-ray Compton scattering is reported. The intensity of Compton-scattered X-rays has shown a position dependence across the flame of the combustion gas, allowing us to estimate the temperature distribution of the combustion flame. The energy spectra of Compton-scattered X-rays have revealed a significant difference across the combustion reaction zone, which enables us to detect the combustion reaction. These results demonstrate that high-energy X-ray Compton scattering can be employed as an in situ technique to probe inside a combustion reaction.

  9. Segal crystallinity index revisited by the simulation of x-ray diffraction patterns of cotton cellulose IB and cellulose II

    Science.gov (United States)

    The Segal method estimates the amorphous fraction of cellulose IB materials simply based on intensity at 18o 20 in an X-ray diffraction pattern and was extended to cellulose II using 16o 2O intensity. To address the dependency of Segal amorphous intensity on crystal size, cellulose polymorph, and th...

  10. Discrete tomographic reconstruction of 2D polycrystal orientation maps from X-ray diffraction projections using Gibbs priors

    DEFF Research Database (Denmark)

    Rodek, L.; Knudsen, E.; Poulsen, H.F.

    2005-01-01

    The determination of crystalline structures is a demanding and fundamental task of crystallography. This paper offers a new approach for rendering a 2D grain map of a polycrystal based on an orientation map reconstructed from X-ray diffraction patterns. The orientation map is produced by a Bayesian...

  11. Smoothing of X-ray diffraction data and K (alpha)2 elimination using penalized likelihood and the composite link model

    NARCIS (Netherlands)

    De Rooi, J.J.; Van der Pers, N.M.; Hendrikx, R.W.A.; Delhez, R.; Bottger, A.J.; Eilers, P.H.C.

    2014-01-01

    X-ray diffraction scans consist of series of counts; these numbers obey Poisson distributions with varying expected values. These scans are often smoothed and the K2 component is removed. This article proposes a framework in which both issues are treated. Penalized likelihood estimation is used to

  12. Characterization of a Test for Invasive Breast Cancer Using X-ray Diffraction of Hair - Results of a Clinical Trial

    Directory of Open Access Journals (Sweden)

    Gary L. Corino

    2009-11-01

    Full Text Available Objective: To assess the performance of a test for breast cancer utilizing synchrotron x-ray diffraction analysis of scalp hair from women undergoing diagnostic radiology assessment. Design and Setting: A double-blinded clinical trial of women who attended diagnostic radiology clinics in Australia. Patients: 1796 women referred for diagnostic radiology, with no previous history of cancer. Main Outcome Measures: Sensitivity, specificity and accuracy of the hair test analysis compared to the gold standard of imaging followed by biopsy where indicated. Results: The hair-based assay had an overall accuracy of >77% and a negative predictive value of 99%. For all women, the sensitivity of both mammography and x-ray diffraction alone was 64%, but when used together the sensitivity rose to 86%. The sensitivity of the hair test for women under the age of 70 was 74%. Conclusion: In this large population trial the association between the presence of breast cancer and an altered hair fibre X-ray diffraction pattern previously reported has been confirmed. It appears that mammography and X-ray diffraction of hair detect different populations of breast cancers, and are synergistic when used together.

  13. X-ray diffraction study of the composition and strain fields in buried SiGe islands

    NARCIS (Netherlands)

    Hrauda, N.; Zhang, J.J.; Stoffel, M.; Stangl, J.; Bauer, G.; Rehman-Khan, A.; Holy, V.; Schmidt, O.G.; Jovanovic, V.; Nanver, L.K.

    2009-01-01

    We report on studies of strain and composition of two-dimensionally ordered SiGe islands grown by molecular beam epitaxy using high resolution x-ray diffraction. To ensure a small size distribution of the islands, pit-patterned 4 (001) Si wafers were used as substrates. The Si wafers were patterned

  14. Phase transitions in diglyceride monolayers studied by computer simulations, pressure-area isotherms and x-ray diffraction

    DEFF Research Database (Denmark)

    Peters, Günther H.J.; Toxværd, S.; Larsen, N.B.

    1994-01-01

    1,2-sn-diglyceride monolayers exhibit unique and complex phase transitions as a function of surface pressure. The dynamical response of the layer on expanding the film has been investigated by computer simulations, (π-A) isotherms and grazing-incidence X-ray diffraction. Good agreement is found b...

  15. Systematic investigation of lard polymorphism using combined DSC and time-resolved synchrotron X-ray diffraction

    NARCIS (Netherlands)

    Kalnin, D.J.E.; Lesieur, P.; Artzner, F.; Keller, G.; Ollivon, M.

    2005-01-01

    The polymorphic behavior of lard was systematically investigated by differential scanning calorimetry (DSC) while simultaneously monitoring the formation of the different crystal forms with X-ray diffraction (XRDT). To interpret the complex polymorphic evolution of the sample analyzed by regular

  16. Non-Destructive Quantification of Plastic Deformation in Steel: Employing X-Ray Diffraction Peak Broadening Analysis

    Science.gov (United States)

    2013-09-01

    fondement scientifique des analyses de l’étalement des pics de DRX et à élaborer une méthode d’évaluation de la déformation plastique des alliages...R), or (U). It is not necessary to include here abstracts in both official languages unless the text is bilingual.) The X-ray diffraction

  17. FELIX: an algorithm for indexing multiple crystallites in X-ray free-electron laser snapshot diffraction images

    DEFF Research Database (Denmark)

    Beyerlein, Kenneth R.; White, Thomas A.; Yefanov, Oleksandr

    2017-01-01

    A novel algorithm for indexing multiple crystals in snapshot X-ray diffraction images, especially suited for serial crystallography data, is presented. The algorithm, FELIX, utilizes a generalized parametrization of the Rodrigues-Frank space, in which all crystal systems can be represented without...

  18. In situ electrochemical high-energy X-ray diffraction using a capillary working electrode cell geometry.

    Science.gov (United States)

    Young, Matthias J; Bedford, Nicholas M; Jiang, Naisheng; Lin, Deqing; Dai, Liming

    2017-07-01

    The ability to generate new electrochemically active materials for energy generation and storage with improved properties will likely be derived from an understanding of atomic-scale structure/function relationships during electrochemical events. Here, the design and implementation of a new capillary electrochemical cell designed specifically for in situ high-energy X-ray diffraction measurements is described. By increasing the amount of electrochemically active material in the X-ray path while implementing low-Z cell materials with anisotropic scattering profiles, an order of magnitude enhancement in diffracted X-ray signal over traditional cell geometries for multiple electrochemically active materials is demonstrated. This signal improvement is crucial for high-energy X-ray diffraction measurements and subsequent Fourier transformation into atomic pair distribution functions for atomic-scale structural analysis. As an example, clear structural changes in LiCoO2 under reductive and oxidative conditions using the capillary cell are demonstrated, which agree with prior studies. Accurate modeling of the LiCoO2 diffraction data using reverse Monte Carlo simulations further verifies accurate background subtraction and strong signal from the electrochemically active material, enabled by the capillary working electrode geometry.

  19. Stability of dislocation structures in copper towards stress relaxation investigated by high angular resolution 3D X-ray diffraction

    DEFF Research Database (Denmark)

    Jakobsen, Bo; Poulsen, Henning Friis; Lienert, Ulrich

    2009-01-01

    A 300 µm thick tensile specimen of OFHC copper is subjected to a tensile loading sequence and deformed to a maximal strain of 3.11%. Using the novel three-dimensional X-ray diffraction method High angular resolution 3DXRD', the evolution of the microstructure within a deeply embedded grain is cha...

  20. Electrostatic Molecular Interaction from X-ray Diffraction Data. I. Development of the Method; Test on Pyrazine

    NARCIS (Netherlands)

    Moss, Grant; Feil, Dirk

    1981-01-01

    Electrostatic interaction is often an important part of the total interaction between molecules. It depends on the electron density distribution in the participating molecules, which can, in principle, be determined by X-ray diffraction methods. A method is described to calculate the electrostatic