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Sample records for x-ray diffraction line

  1. EFFECT OF SATELLITE LINES FROM X-RAY SOURCE ON X-RAY DIFFRACTION PEAKS

    EPA Science Inventory

    The article discusses the development of a method for relating reactivity to crystallite size and strain parameters obtained by the Warren-Averbach technique. PA has been using crystallite size and strain data obtained from x-ray diffraction (XRD) peak profile analysis to predict...

  2. X-Ray Diffraction.

    ERIC Educational Resources Information Center

    Smith, D. K.; Smith, K. L.

    1980-01-01

    Reviews applications in research and analytical characterization of compounds and materials in the field of X-ray diffraction, emphasizing new developments in applications and instrumentation in both single crystal and powder diffraction. Cites 414 references. (CS)

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

    NASA Astrophysics Data System (ADS)

    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

  4. THE EFFECT OF SATELLITE LINES FROM THE X-RAY SOURCE ON X-RAY DIFFRACTION PEAKS

    EPA Science Inventory

    The article discusses the development of a method for relating reactivity to crystallite size and strain parameters obtained by the Warren-Averbach technique. EPA has been using crystallite size and strain data obtained from x-ray diffraction (XRD) peak profile analysis to predic...

  5. X-ray diffraction line profile analysis of KBr thin films

    NASA Astrophysics Data System (ADS)

    Rai, R.; Triloki, Triloki; Singh, B. K.

    2016-08-01

    In the present work, the microcrystalline characteristics of KBr thin films have been investigated by evaluating the breadth of diffraction peak. The Williamson-Hall, the Size-Strain plot and the single-line Voigt methods are employed to deconvolute the finite crystallite size and microstrain contribution from the broaden X-ray profile. The texture coefficient and dislocation density have been determined along each diffraction peak. Other relevant physical parameters such as stress, Young's modulus and energy density are also estimated using uniform stress deformation and uniform deformation energy density approximation of Williamson-Hall method.

  6. In-line holography and coherent diffractive imaging with x-ray waveguides

    SciTech Connect

    De Caro, L.; Giannini, C.; Guagliardi, A.; Mocuta, C.; Metzger, T. H.; Cedola, A.; Burkeeva, I.; Lagomarsino, S.

    2008-02-15

    A Fresnel coherent diffraction imaging experiment with hard x rays is here presented, using two planar crossed waveguides as optical elements, leading to a virtual pointlike source. The coherent wave field obtained with this setup is used to illuminate a micrometric single object having the shape of a butterfly. A digital two-dimensional in-line holographic reconstruction of the unknown object at low resolution (200 nm) has been obtained directly via fast Fourier transform (FFT) of the raw data. The object and its twin image are well separated because suitable geometrical conditions are satisfied. A good estimate of the incident wave field phase has been extracted directly from the FFT of the raw data. A partial object reconstruction with 50 nm spatial resolution was achieved by fast iterative phase retrieval, the major limitation for a full reconstruction being the nonideal structure of the guided beam. The method offers a route for fast and reliable phase retrieval in x-ray coherent diffraction.

  7. In-line holography and coherent diffractive imaging with x-ray waveguides

    NASA Astrophysics Data System (ADS)

    de Caro, L.; Giannini, C.; Pelliccia, D.; Mocuta, C.; Metzger, T. H.; Guagliardi, A.; Cedola, A.; Burkeeva, I.; Lagomarsino, S.

    2008-02-01

    A Fresnel coherent diffraction imaging experiment with hard x rays is here presented, using two planar crossed waveguides as optical elements, leading to a virtual pointlike source. The coherent wave field obtained with this setup is used to illuminate a micrometric single object having the shape of a butterfly. A digital two-dimensional in-line holographic reconstruction of the unknown object at low resolution (200nm) has been obtained directly via fast Fourier transform (FFT) of the raw data. The object and its twin image are well separated because suitable geometrical conditions are satisfied. A good estimate of the incident wave field phase has been extracted directly from the FFT of the raw data. A partial object reconstruction with 50nm spatial resolution was achieved by fast iterative phase retrieval, the major limitation for a full reconstruction being the nonideal structure of the guided beam. The method offers a route for fast and reliable phase retrieval in x-ray coherent diffraction.

  8. X-Ray Diffraction Apparatus

    NASA Technical Reports Server (NTRS)

    Blake, David F. (Inventor); Bryson, Charles (Inventor); Freund, Friedmann (Inventor)

    1996-01-01

    An x-ray diffraction apparatus for use in analyzing the x-ray diffraction pattern of a sample is introduced. The apparatus includes a beam source for generating a collimated x-ray beam having one or more discrete x-ray energies, a holder for holding the sample to be analyzed in the path of the beam, and a charge-coupled device having an array of pixels for detecting, in one or more selected photon energy ranges, x-ray diffraction photons produced by irradiating such a sample with said beam. The CCD is coupled to an output unit which receives input information relating to the energies of photons striking each pixel in the CCD, and constructs the diffraction pattern of photons within a selected energy range striking the CCD.

  9. Submicron X-ray diffraction

    SciTech Connect

    MacDowell, Alastair; Celestre, Richard; Tamura, Nobumichi; Spolenak, Ralph; Valek, Bryan; Brown, Walter; Bravman, John; Padmore, Howard; Batterman, Boris; Patel, Jamshed

    2000-08-17

    At the Advanced Light Source in Berkeley the authors have instrumented a beam line that is devoted exclusively to x-ray micro diffraction problems. By micro diffraction they mean those classes of problems in Physics and Materials Science that require x-ray beam sizes in the sub-micron range. The instrument is for instance, capable of probing a sub-micron size volume inside micron sized aluminum metal grains buried under a silicon dioxide insulating layer. The resulting Laue pattern is collected on a large area CCD detector and automatically indexed to yield the grain orientation and deviatoric (distortional) strain tensor of this sub-micron volume. A four-crystal monochromator is then inserted into the beam, which allows monochromatic light to illuminate the same part of the sample. Measurement of diffracted photon energy allows for the determination of d spacings. The combination of white and monochromatic beam measurements allow for the determination of the total strain/stress tensor (6 components) inside each sub-micron sized illuminated volume of the sample.

  10. THE CHARACTERIZATION OF A SOLID SORBENT WITH CRYSTALLITE SIZE AND STRAIN DATA FROM X-RAY DIFFRACTION LINE BROADENING

    EPA Science Inventory

    The paper gives results of the characterization of a solid sorbent with crystallite size and strain data from x-ray diffraction line broadening, as part of an EPA investigation of the injection of dry Ca(OH)2 into coal-fired electric power plant burners for the control of SO2 emi...

  11. Advanced X-ray diffractive optics

    NASA Astrophysics Data System (ADS)

    Vila-Comamala, J.; Jefimovs, K.; Pilvi, T.; Ritala, M.; Sarkar, S. S.; Solak, H. H.; Guzenko, V. A.; Stampanoni, M.; Marone, F.; Raabe, J.; Tzvetkov, G.; Fink, R. H.; Grolimund, D.; Borca, C. N.; Kaulich, B.; David, C.

    2009-09-01

    X-ray microscopy greatly benefits from the advances in x-ray optics. At the Paul Scherrer Institut, developments in x-ray diffractive optics include the manufacture and optimization of Fresnel zone plates (FZPs) and diffractive optical elements for both soft and hard x-ray regimes. In particular, we demonstrate here a novel method for the production of ultra-high resolution FZPs. This technique is based on the deposition of a zone plate material (iridium) onto the sidewalls of a prepatterned template structure (silicon) by atomic layer deposition. This approach overcomes the limitations due to electron-beam writing of dense patterns in FZP fabrication and provides a clear route to push the resolution into sub-10 nm regime. A FZP fabricated by this method was used to resolve test structures with 12 nm lines and spaces at the scanning transmission x-ray microscope of the PolLux beamline of the Swiss Light Source at 1.2 keV photon energy.

  12. Diffractive X-Ray Telescopes

    NASA Technical Reports Server (NTRS)

    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.

  13. Determining fine-structure parameters for tungsten powder and filings by harmonic analysis of x-ray diffraction lines

    SciTech Connect

    Kravchik, A.E.; Moshkina, T.I.; Osmakov, A.S.

    1986-12-01

    Evidence has been accumulating on determining fine-structure parameters by line shape harmonic analysis (LSHA) although many aspects remain unresolved. In this paper, the authors discuss the interpretations afresh, on-going improvements in x-ray techniques, in recording methods, and in processing the data, as well as in programs for determining the parameters by LSHA. The authors selected tungsten because of its bcc lattice, whose diffraction peaks are widely separated, which almost completely rules out their overlapping even if there is considerable broadening, such as is produced by large plastic strain. The material was produced in two ways: by firing a tungsten single crystal and by grinding VChDK tungsten powder in a laboratory vibration mill for 10, 20, 30, 50, and 100 h.

  14. An Implementation of the Fundamental Parameters Approach for Analysis of X-ray Powder Diffraction Line Profiles.

    PubMed

    Mendenhall, Marcus H; Mullen, Katharine; Cline, James P

    2015-01-01

    This work presents an open implementation of the Fundamental Parameters Approach (FPA) models for analysis of X-ray powder diffraction line profiles. The original literature describing these models was examined and code was developed to allow for their use within a Python based least squares refinement algorithm. The NIST interest in the FPA method is specific to its ability to account for the optical aberrations of the powder diffraction experiment allowing for an accurate assessment of lattice parameter values. Lattice parameters are one of the primary certified measurands of NIST Standard Reference Materials (SRMs) for powder diffraction. Lattice parameter values obtained from analysis of data from SRMs 640e and 660c using both the NIST FPA Python code and the proprietary, commercial code Topas, that constitutes the only other actively supported, complete implementation of FPA models within a least-squares data analysis environment, agreed to within 2 fm. This level of agreement demonstrates that both the NIST code and Topas constitute an accurate implementation of published FPA models. PMID:26958448

  15. An Implementation of the Fundamental Parameters Approach for Analysis of X-ray Powder Diffraction Line Profiles

    PubMed Central

    Mendenhall, Marcus H.; Mullen, Katharine; Cline, James P.

    2015-01-01

    This work presents an open implementation of the Fundamental Parameters Approach (FPA) models for analysis of X-ray powder diffraction line profiles. The original literature describing these models was examined and code was developed to allow for their use within a Python based least squares refinement algorithm. The NIST interest in the FPA method is specific to its ability to account for the optical aberrations of the powder diffraction experiment allowing for an accurate assessment of lattice parameter values. Lattice parameters are one of the primary certified measurands of NIST Standard Reference Materials (SRMs) for powder diffraction. Lattice parameter values obtained from analysis of data from SRMs 640e and 660c using both the NIST FPA Python code and the proprietary, commercial code Topas, that constitutes the only other actively supported, complete implementation of FPA models within a least-squares data analysis environment, agreed to within 2 fm. This level of agreement demonstrates that both the NIST code and Topas constitute an accurate implementation of published FPA models. PMID:26958448

  16. X-Ray Diffractive Optics

    NASA Technical Reports Server (NTRS)

    Dennis, Brian; Li, Mary; Skinner, Gerald

    2013-01-01

    X-ray optics were fabricated with the capability of imaging solar x-ray sources with better than 0.1 arcsecond angular resolution, over an order of magnitude finer than is currently possible. Such images would provide a new window into the little-understood energy release and particle acceleration regions in solar flares. They constitute one of the most promising ways to probe these regions in the solar atmosphere with the sensitivity and angular resolution needed to better understand the physical processes involved. A circular slit structure with widths as fine as 0.85 micron etched in a silicon wafer 8 microns thick forms a phase zone plate version of a Fresnel lens capable of focusing approx. =.6 keV x-rays. The focal length of the 3-cm diameter lenses is 100 microns, and the angular resolution capability is better than 0.1 arcsecond. Such phase zone plates were fabricated in Goddard fs Detector Development Lab. (DDL) and tested at the Goddard 600-microns x-ray test facility. The test data verified that the desired angular resolution and throughput efficiency were achieved.

  17. Diffraction enhanced x-ray imaging

    SciTech Connect

    Thomlinson, W.; Zhong, Z.; Chapman, D.; Johnston, R.E.; Sayers, D.

    1997-09-01

    Diffraction enhanced imaging (DEI) is a new x-ray radiographic imaging modality using synchrotron x-rays which produces images of thick absorbing objects that are almost completely free of scatter. They show dramatically improved contrast over standard imaging applied to the same phantoms. The contrast is based not only on attenuation but also the refraction and diffraction properties of the sample. The diffraction component and the apparent absorption component (absorption plus extinction contrast) can each be determined independently. This imaging method may improve the image quality for medical applications such as mammography.

  18. Beyond hard x-ray photoelectron spectroscopy: Simultaneous combination with x-ray diffraction

    SciTech Connect

    Rubio-Zuazo, Juan; Castro, German R.

    2013-05-15

    Hard x-ray photoelectron spectroscopy (HAXPES) is a powerful and novel emerging technique for the nondestructive determination of electronic properties and chemical composition of bulk, buried interfaces and surfaces. It benefits from the exceptionally large escape depth of high kinetic energy photoelectrons, increasing the information depth up to several tens of nanometers. Complementing HAXPES with an atomic structure sensitive technique (such as x-ray diffraction) opens a new research field with major applications for materials science. At SpLine, the Spanish CRG beamline at the European Synchrotron Radiation Facility, we have developed a novel experimental set-up that combines HAXPES and x-ray diffraction (x-ray reflectivity, surface x-ray diffraction, grazing incidence x-ray diffraction, and reciprocal space maps). Both techniques can be operated simultaneously on the same sample and using the same excitation source. The set-up includes a robust 2S + 3D diffractometer hosting a ultrahigh vacuum chamber equipped with a unique photoelectron spectrometer (few eV < electron kinetic energy < 15 keV), x-ray tube (Mg/Ti), 15 keV electron gun, and auxiliary standard surface facilities (molecular beam epitaxy evaporator, ion gun, low energy electron diffraction, sample heating/cooling system, leak valves, load-lock sample transfer, etc.). This end-station offers the unique possibility of performing simultaneous HAXPES + x-ray diffraction studies. In the present work, we describe the experimental set-up together with two experimental examples that emphasize its outstanding capabilities: (i) nondestructive characterization of the Si/Ge and HfO{sub 2}/SiO{sub 2} interfaces on Ge-based CMOS devices, and (ii) strain study on La{sub 0.7}Ca{sub 0.3}MnO{sub 3} ultrathin films grown on SrTiO{sub 3}(001) substrate.

  19. Interlaced X-ray diffraction computed tomography

    PubMed Central

    Vamvakeros, Antonios; Jacques, Simon D. M.; Di Michiel, Marco; Senecal, Pierre; Middelkoop, Vesna; Cernik, Robert J.; Beale, Andrew M.

    2016-01-01

    An X-ray diffraction computed tomography data-collection strategy that allows, post experiment, a choice between temporal and spatial resolution is reported. This strategy enables time-resolved studies on comparatively short timescales, or alternatively allows for improved spatial resolution if the system under study, or components within it, appear to be unchanging. The application of the method for studying an Mn–Na–W/SiO2 fixed-bed reactor in situ is demonstrated. Additionally, the opportunities to improve the data-collection strategy further, enabling post-collection tuning between statistical, temporal and spatial resolutions, are discussed. In principle, the interlaced scanning approach can also be applied to other pencil-beam tomographic techniques, like X-ray fluorescence computed tomography, X-ray absorption fine structure computed tomography, pair distribution function computed tomography and tomographic scanning transmission X-ray microscopy. PMID:27047305

  20. Single Particle X-ray Diffractive Imaging

    SciTech Connect

    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.

  1. The Dynamical Theory of X Ray Diffraction

    ERIC Educational Resources Information Center

    Balchin, A. A.; Whitehouse, C. R.

    1974-01-01

    Summarizes the Darwin theory of x-ray diffraction in thin crystals or crystals with a mosaic texture and its modified application to crystals with three-dimensional electrostatic dipoles. Indicates that the dynamical theory is brought into its present relevance by the improvement of single crystal growth techniques. (CC)

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

    DOEpatents

    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.

  3. X-Ray Diffraction on NIF

    SciTech Connect

    Eggert, J H; Wark, J

    2012-02-15

    The National Ignition Facility (NIF) is currently a 192 beam, 1.6 MJ laser. NIF Ramp-Compression Experiments have already made the relevant exo-planet pressure range from 1 to 50 Mbar accessible. We Proposed to Study Carbon Phases by X-Ray Diffraction on NIF. Just a few years ago, ultra-high pressure phase diagrams for materials were very 'simple'. New experiments and theories point out surprising and decidedly complex behavior at the highest pressures considered. High pressures phases of aluminum are also predicted to be complex. Recent metadynamics survey of carbon proposed a dynamic pathway among multiple phases. We need to develop diagnostics and techniques to explore this new regime of highly compressed matter science. X-Ray Diffraction - Understand the phase diagram/EOS/strength/texture of materials to 10's of Mbar. Strategy and physics goals: (1) Powder diffraction; (2) Begin with diamond; (3) Continue with metals etc.; (4) Explore phase diagrams; (5) Develop liquid diffraction; and (6) Reduce background/improve resolution.

  4. Quantitative evaluation of the broadening of x-ray diffraction, Raman, and photoluminescence lines by dislocation-induced strain in heteroepitaxial GaN films

    NASA Astrophysics Data System (ADS)

    Kaganer, Vladimir M.; Jenichen, Bernd; Ramsteiner, Manfred; Jahn, Uwe; Hauswald, Christian; Grosse, Frank; Fernández-Garrido, Sergio; Brandt, Oliver

    2015-09-01

    Experimental x-ray diffraction, Raman, and photoluminescence line profiles from GaN films with different densities of threading dislocations are modeled using Monte Carlo calculations of the strain distribution due to these dislocations. We quantitatively analyze and compare the respective line broadenings predicted by these calculations for different dislocation densities. X-ray diffraction and Raman measurements reveal the strain in the whole volume of the film, due to the large penetration depth of the corresponding radiation, while photoluminescence measurements are sensitive to the strain close to the film surface, in a layer limited by the penetration depth of the radiation used for excitation. This difference in information depths becomes especially important for films in which the threading dislocation density is continuously decreasing during growth, as it can be achieved by vapor phase epitaxy methods. An additional narrowing of photoluminescence lines occurs due to two effects: first, the elastic relaxation of the dislocation strain at the free surface, and second, the suppression of luminescence from the most highly strained regions around the dislocation cores which act as centers of nonradiative recombination.

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

    PubMed

    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. PMID:22186282

  6. X-ray microimaging by diffractive techniques

    SciTech Connect

    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.

  7. In-line x-ray phase-contrast tomography and diffraction-contrast tomography study of the ferrite-cementite microstructure in steel

    NASA Astrophysics Data System (ADS)

    Kostenko, Alexander; Sharma, Hemant; Dere, E. Gözde; King, Andrew; Ludwig, Wolfgang; Van Oel, Wim; Offerman, S. Erik; Stallinga, Sjoerd; Vliet, Lucas J. van

    2012-05-01

    This work presents the development of a non-destructive imaging technique for the investigation of the microstructure of cementite grains embedded in a ferrite matrix of medium-carbon steel. The measurements were carried out at the material science beamline of the European Synchrotron Radiation Facility (ESRF) ID11. It was shown that in-line X-ray phase-contrast tomography (PCT) can be used for the detection of cementite grains of several microns in size. X-ray PCT of the cementite structure can be achieved by either a `single distance' or a `multiple distance' acquisition protocol. The latter permits quantitative phase retrieval. A second imaging technique, X-ray diffraction-contrast tomography (DCT), was employed to obtain information about the shapes and crystallographic orientations of the distinct ferrite grains surrounding the cementite structures. The initial results demonstrate the feasibility of determining the geometry of the cementite grains after the austenite-ferrite phase-transformation in a non-destructive manner. The results obtained with PCT and DCT are verified with ex-situ optical microscopy studies of the same specimen.

  8. Diffraction grating transmission efficiencies for XUV and soft x rays.

    PubMed

    Schnopper, H W; Van Speybroeck, L P; Delvaille, J P; Epstein, A; Källne, E; Bachrach, R Z; Dijkstra, J; Lantward, L

    1977-04-01

    Efficiencies for diffraction of 45-275-eV x rays into orders by interferometrically formed, electrodeposited, gold transmission gratings have been measured on the 4 degrees beam line at the Stanford Synchrotron Radiation Project (SSRP). Anomalous dispersion affects the observed efficiency since the gold is partially transmitting to x rays. Model calculations which include anomalous dispersion are in good agreement with observations. With a suitable choice of material and thickness, a grating can be optimized for a given wavelength range by reducing the zero order transmission and enhancing the higher orders. Even orders are suppressed for a grating with equal slit and wire sizes. PMID:20168641

  9. Transient x-ray diffraction and its application to materials science and x-ray optics

    SciTech Connect

    Hauer, A.A.; Kopp, R.; Cobble, J.; Kyrala, G.; Springer, R.

    1997-12-01

    Time resolved x-ray diffraction and scattering have been applied to the measurement of a wide variety of physical phenomena from chemical reactions to shock wave physics. Interest in this method has heightened in recent years with the advent of versatile, high power, pulsed x-ray sources utilizing laser plasmas, electron beams and other methods. In this article, we will describe some of the fundamentals involved in time resolved x-ray diffraction, review some of the history of its development, and describe some recent progress in the field. In this article we will emphasize the use of laser-plasmas as the x-ray source for transient diffraction.

  10. Elimination of X-Ray Diffraction through Stimulated X-Ray Transmission

    NASA Astrophysics Data System (ADS)

    Wu, B.; Wang, T.; Graves, C. E.; Zhu, D.; Schlotter, W. F.; Turner, J. J.; Hellwig, O.; Chen, Z.; Dürr, H. A.; Scherz, A.; Stöhr, J.

    2016-07-01

    X-ray diffractive imaging with laterally coherent x-ray free-electron laser (XFEL) pulses is increasingly utilized to obtain ultrafast snapshots of matter. Here we report the amazing disappearance of single-shot charge and magnetic diffraction patterns recorded with resonantly tuned, narrow bandwidth XFEL pulses. Our experimental results reveal the exquisite sensitivity of single-shot charge and magnetic diffraction patterns of a magnetic film to the onset of field-induced stimulated elastic x-ray forward scattering. The loss in diffraction contrast, measured over 3 orders of magnitude in intensity, is in remarkable quantitative agreement with a recent theory that is extended to include diffraction.

  11. X-ray diffraction microtomography using synchrotron radiation

    NASA Astrophysics Data System (ADS)

    Barroso, R. C.; Lopes, R. T.; de Jesus, E. F. O.; Oliveira, L. F.

    2001-09-01

    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 obtained diffraction patterns form the basis of a selective tomography technique. Preliminary images are presented.

  12. Glass transition in ferroic glass K x (ND4)1-x D2PO4: a complete x-ray diffraction line shape analysis

    NASA Astrophysics Data System (ADS)

    Ranjan Choudhury, Rajul; Chitra, R.; Jayakrishnan, V. B.

    2016-03-01

    Quenching of dynamic disorder in glassy systems is termed as the glass transition. Ferroic glasses belong to the class of paracrystalline materials having crystallographic order in-between that of a perfect crystal and amorphous material, a classic example of ferroic glass is the solid solution of ferroelectric deuterated potassium dihydrogen phosphate and antiferroelectric deuterated ammonium dihydrogen phosphate. Lowering temperature of this ferroic glass can lead to a glass transition to a quenched disordered state. The subtle atomic rearrangement that takes place at such a glass transition can be revealed by careful examination of the temperature induced changes occurring in the x-ray powder diffraction (XRD) patterns of these materials. Hence we report here results of a complete diffraction line shape analysis of the XRD patterns recorded at different temperatures from deuterated mixed crystals DK x A1-x DP with mixing concentration x ranging as 0 < x < 1. Changes observed in diffraction peak shapes have been explained on the basis of structural rearrangements induced by changing O-D-O hydrogen bond dynamics in these paracrystals.

  13. X-Ray-Diffraction Tests Of Irradiated Electronic Devices: II

    NASA Technical Reports Server (NTRS)

    Shaw, David C.; Lowry, Lynn E.; Barnes, Charles E.

    1993-01-01

    Report describes research on use of x-ray diffraction to measure stresses in metal conductors of complementary metal oxide/semiconductor (CMOS) integrated circuits exposed to ionizing radiation. Expanding upon report summarized in "X-Ray-Diffraction Tests Of Irradiated Electronic Devices: I" (NPO-18803), presenting data further suggesting relationship between electrical performances of circuits and stresses and strains in metal conductors.

  14. Scanning CCD Detector for X-ray Powder Diffraction

    NASA Astrophysics Data System (ADS)

    Madden, T.; Baldwin, J.; Von Dreele, R.; Suchomel, M.; Toby, B. H.

    2014-03-01

    We discuss the design, fabrication and use of a custom CCD detector for x-ray powder diffraction measurements. The detector is mounted on a diffractometer arm, where line-by-line readout of the CCD is coupled to continuous motion of the arm. As the arm moves, the data from the CCD detector are accumulated and can be viewed as if it were a "film strip" with partial powder diffraction rings. Because of the unique design of the camera, both high-resolution and rapid measurements can be performed. Powder diffraction patterns are collected with speeds of a few minutes, or less, with many of the advantages of large area position-sensitive detectors, for example amorphous silicon flat panels, such as high sensitivity, direct evidence of grainy samples and freedom from low-angle asymmetry, but with resolution better than linear position-sensitive detectors and nearly as good as the ultimate in resolution, analyser-crystal detection [2,3].

  15. High-Energy X-Ray Diffraction Analysis Tool

    Energy Science and Technology Software Center (ESTSC)

    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 modularmore » 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.« less

  16. High-Energy X-Ray Diffraction Analysis Tool

    SciTech Connect

    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.

  17. High-Resolution Detector For X-Ray Diffraction

    NASA Technical Reports Server (NTRS)

    Carter, Daniel C.; Withrow, William K.; Pusey, Marc L.; Yost, Vaughn H.

    1988-01-01

    Proposed x-ray-sensitive imaging detector offers superior spatial resolution, counting-rate capacity, and dynamic range. Instrument based on laser-stimulated luminescence and reusable x-ray-sensitive film. Detector scans x-ray film line by line. Extracts latent image in film and simultaneously erases film for reuse. Used primarily for protein crystallography. Principle adapted to imaging detectors for electron microscopy and fluorescence spectroscopy and general use in astronomy, engineering, and medicine.

  18. An X-ray diffraction study of titanium oxidation

    NASA Technical Reports Server (NTRS)

    Wiedemann, K. E.; Unnam, J.

    1984-01-01

    Titanium specimens of commercial purity were exposed at 1100 to 1400 F to laboratory air for times up to 100 hours. The extent of substrate contamination by interstitial oxygen was was determined by a new X-ray diffraction analysis involving transformation of X-ray diffraction intensity bands. The oxygen solid-solubility at the oxide-metal interfaces and its variation with time at temperature were also determined. Diffusion coefficients are deduced from the oxygen depth profiles.

  19. X-ray diffraction study of lead chloride

    NASA Astrophysics Data System (ADS)

    Nitsch, K.; Knížek, K.; Rodová, M.

    1994-08-01

    PbCl 2 was examined by X-ray diffraction in order to test information about polymorphism in this compound. X-ray diffraction patterns of PbCl 2 crystallized from the aqueous solution, as well as of PbCl 2 molten and quenched, are the same. Two modifications in PbCl 2 were not found and polymorphism was not confirmed.

  20. Microbeam X-Ray Standing Wave and High Resolution Diffraction

    SciTech Connect

    Kazimirov, A.; Bilderback, D.H.; Huang, R.; Sirenko, A.

    2004-05-12

    Post-focusing collimating optics are introduced as a tool to condition X-ray microbeams for the use in high-resolution X-ray diffraction and scattering techniques. As an example, a one-bounce imaging capillary and miniature Si(004) channel-cut crystal were used to produce a microbeam with 10 {mu}m size and an ultimate angular resolution of 2.5 arc sec. This beam was used to measure the strain in semiconductor microstructures by using X-ray high resolution diffraction and standing wave techniques to {delta}d/d < 5x10-4.

  1. Precise rotational alignment of x-ray transmission diffraction gratings

    SciTech Connect

    Hill, S.L.

    1988-03-28

    Gold transmission diffraction gratings used for x-ray spectroscopy must sometimes be rotationally aligned to the axis of a diagnostic instrument to within sub-milliradian accuracy. We have fabricated transmission diffraction gratings with high line-densities (grating period of 200 and 300 nm) using uv holographic and x-ray lithography. Since the submicron features of the gratings are not optically visible, precision alignment is time consuming and difficult to verify in situ. We have developed a technique to write an optically visible alignment pattern onto these gratings using a scanning electron microscope (SEM). At high magnification (15000 X) several submicron lines of the grating are observable in the SEM, making it possible to write an alignment pattern parallel to the grating lines in an electron-beam-sensitive coating that overlays the grating. We create an alignment pattern by following a 1-cm-long grating line using the SEM's joystick-controlled translation stage. By following the same grating line we are assured the traveled direction of the SEM electron beam is parallel to the grating to better than 10 ..mu..radian. The electron-beam-exposed line-width can be large (5 to 15 ..mu..m wide) depending on the SEM magnification, and is therefore optically visible. The exposed pattern is eventually made a permanent feature of the grating by ion beam etching or gold electroplating. The pattern can be used to accurately align the grating to the axis of a diagnostic instrument. More importantly, the alignment of the grating can be quickly verified in situ.

  2. In-situ mechanical testing during X-ray diffraction

    SciTech Connect

    Van Swygenhoven, Helena Van Petegem, Steven

    2013-04-15

    Deforming metals during recording X-ray diffraction patterns is a useful tool to get a deeper understanding of the coupling between microstructure and mechanical behaviour. With the advances in flux, detector speed and focussing techniques at synchrotron facilities, in-situ mechanical testing is now possible during powder diffraction and Laue diffraction. The basic principle is explained together with illustrative examples.

  3. X-ray diffraction as a local probe tool.

    PubMed

    Stangl, J; Mocuta, C; Diaz, A; Metzger, T H; Bauer, G

    2009-12-01

    For the structural characterization of nanoscale objects, X-ray diffraction is widely used as a technique complementing local probe analysis methods such as scanning electron microscopy and transmission electron microscopy. Details on strain distributions, chemical composition, or size and shape of nanostructures are addressed. X-ray diffraction traditionally obtains very good statistically averaged properties over large ensembles-provided this averaging is meaningful for ensembles with sufficiently small dispersion of properties. In many cases, however, it is desirable to combine different analysis techniques on exactly the same nano-object, for example, to gain a more detailed insight into the interdependence of properties. X-ray beams focused to diameters in the sub-micron range, which are available at third-generation synchrotron sources, allow for such X-ray diffraction studies of individual nano-objects. PMID:19856372

  4. X-ray diffraction topography image materials by molecular probe

    NASA Astrophysics Data System (ADS)

    Hentschel, Manfred P.; Lange, Axel; Schors, Joerg; Wald, Oliver

    2005-05-01

    Crystallinity, composition, homogeneity and anisotropy determine the mechanical properties of materials significantly, but the performance of most non-destructive techniques is too poor for measuring these micro structures as they are optimized for finding individual flaws/defects. X-ray (wide angle) Diffraction Topography by single beam scanning images molecular information at a spatial resolution of several ten micrometers even in three dimensions. Especially for the non-destructive characterization of composite materials, they provide additional capabilities by crystallographic contrast by the molecular/atomic probe. The different material phases of compounds and their molecular orientation can be imaged e.g. fibers or polymer chain orientation in composites: A sample is scanned or rotated, while only part of the scattering pattern is pointing at an X-ray detector area. Three different methods have been developed: i) planar X-ray Scanning Topography at one or more pre-selected scattering angles provides high contrast of different phases of components. ii) X-Ray Rotation Topography reveals the texture angle of composite fibers and chain polymers. iii) X-ray Diffraction Microscopy images the texture and phase distribution of transversal sections of the material. The principles of Wide Angle X-Ray Diffraction Topography are explained and examples of investigations will be presented. They combine the advantages of radiographic imaging and crystal structure information. The applied X-ray energies are much lower than in NDT radiography, which recommends preferably the application to light weight materials.

  5. X-Ray Diffraction Microscopy of Magnetic Structures

    SciTech Connect

    Turner, J.; Lima, E.; Huang, X.; Krupin, O.; Seu, K.; Parks, D.; Kevan, S.; Kisslinger, K.; McNulty, I.; Gambino, R.; Mangin, S.; Roy, S. and Fischer, P.

    2011-07-14

    We report the first proof-of-principle experiment of iterative phase retrieval from magnetic x-ray diffraction. By using the resonant x-ray excitation process and coherent x-ray scattering, we show that linearly polarized soft x rays can be used to image both the amplitude and the phase of magnetic domain structures. We recovered the magnetic structure of an amorphous terbium-cobalt thin film with a spatial resolution of about 75 nm at the Co L{sub 3} edge at 778 eV. In comparison with soft x-ray microscopy images recorded with Fresnel zone plate optics at better than 25 nm spatial resolution, we find qualitative agreement in the observed magnetic structure.

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

    NASA Astrophysics Data System (ADS)

    Cheung, G.; Hooker, S. M.

    2016-08-01

    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.

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

    SciTech Connect

    Not Available

    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.

  8. Cryogenic X-ray Diffraction Microscopy for Biological Samples

    SciTech Connect

    E Lima; L Wiegart; P Pernot; M Howells; J Timmins; F Zontone; A Madsen

    2011-12-31

    X-ray diffraction microscopy (XDM) is well suited for nondestructive, high-resolution biological imaging, especially for thick samples, with the high penetration power of x rays and without limitations imposed by a lens. We developed nonvacuum, cryogenic (cryo-) XDM with hard x rays at 8 keV and report the first frozen-hydrated imaging by XDM. By preserving samples in amorphous ice, the risk of artifacts associated with dehydration or chemical fixation is avoided, ensuring the imaging condition closest to their natural state. The reconstruction shows internal structures of intact D. radiodurans bacteria in their natural contrast.

  9. Coherent grating x-ray diffraction (CGXD) and its applications

    SciTech Connect

    Shen, Q.

    1996-09-01

    We show that an x-ray interference phenomenon, coherent grating x-ray diffraction (CGXD), can be used to study lateral nanostructure arrays on crystal surfaces and interfaces. Compared to Fraunhofer grating diffraction of visible light, x-ray grating diffraction contains information not only about geometric profiles of the surface but also about the internal crystalline structures and lattice strain distributions in the grating features. The grating diffraction pattern can also be measured in a white-beam Laue method using highly collimated polychromatic synchrotron radiation, which provides a parallel data collection scheme and may be useful in {ital in} {ital situ} studies on evolution of nanostructure arrays. {copyright} {ital 1996 American Institute of Physics.}

  10. X-ray diffraction investigation of ultrafine boron nitride powders

    SciTech Connect

    Gurov, S.V.; Chukalin, V.I.; Rezchikova, T.V.; Torbov, V.J.; Troitskii, V.N.

    1986-01-01

    This paper presents an x-ray diffraction analysis of ultrafine boron nitride powders of different mean particle sizes. Diffraction spectra of the ultrafine boron nitride powders were obtained using a DRON-1 apparatus. The experimental facts are indicative of a turbostratic character of deformation of the hexagonal lattice of ultrafinely divided boron nitride.

  11. X-Ray Diffraction Wafer Mapping Method for Rhombohedral Super-Hetero-Epitaxy

    NASA Technical Reports Server (NTRS)

    Park, Yoonjoon; Choi, Sang Hyouk; King, Glen C.; Elliott, James R.; Dimarcantonio, Albert L.

    2010-01-01

    A new X-ray diffraction (XRD) method is provided to acquire XY mapping of the distribution of single crystals, poly-crystals, and twin defects across an entire wafer of rhombohedral super-hetero-epitaxial semiconductor material. In one embodiment, the method is performed with a point or line X-ray source with an X-ray incidence angle approximating a normal angle close to 90 deg, and in which the beam mask is preferably replaced with a crossed slit. While the wafer moves in the X and Y direction, a narrowly defined X-ray source illuminates the sample and the diffracted X-ray beam is monitored by the detector at a predefined angle. Preferably, the untilted, asymmetric scans are of {440} peaks, for twin defect characterization.

  12. Utilizing broadband X-rays in a Bragg coherent X-ray diffraction imaging experiment.

    PubMed

    Cha, Wonsuk; Liu, Wenjun; Harder, Ross; Xu, Ruqing; Fuoss, Paul H; Hruszkewycz, Stephan O

    2016-09-01

    A method is presented to simplify Bragg coherent X-ray diffraction imaging studies of complex heterogeneous crystalline materials with a two-stage screening/imaging process that utilizes polychromatic and monochromatic coherent X-rays and is compatible with in situ sample environments. Coherent white-beam diffraction is used to identify an individual crystal particle or grain that displays desired properties within a larger population. A three-dimensional reciprocal-space map suitable for diffraction imaging is then measured for the Bragg peak of interest using a monochromatic beam energy scan that requires no sample motion, thus simplifying in situ chamber design. This approach was demonstrated with Au nanoparticles and will enable, for example, individual grains in a polycrystalline material of specific orientation to be selected, then imaged in three dimensions while under load. PMID:27577782

  13. Biological imaging by soft x-ray diffraction microscopy

    SciTech Connect

    Shapiro, D.; Thibault, P.; Beetz, T.; Elser, V.; Howells, M.; Jacobsen, C.; Kirz, J.; Lima, E.; Miao, H.; Neiman, A. M.; Sayre, D.

    2005-10-25

    We have used the method of x-ray diffraction microscopy to image the complex-valued exit wave of an intact and unstained yeast cell. The images of the freeze-dried cell, obtained by using 750-eV x-rays from different angular orientations, portray several of the cell's major internal components to 30-nm resolution. The good agreement among the independently recovered structures demonstrates the accuracy of the imaging technique. To obtain the best possible reconstructions, we have implemented procedures for handling noisy and incomplete diffraction data, and we propose a method for determining the reconstructed resolution. This work represents a previously uncharacterized application of x-ray diffraction microscopy to a specimen of this complexity and provides confidence in the feasibility of the ultimate goal of imaging biological specimens at 10-nm resolution in three dimensions.

  14. High-throughput baggage scanning employing x-ray diffraction for accurate explosives detection

    NASA Astrophysics Data System (ADS)

    Green, Michael C.; Partain, Larry D.

    2003-07-01

    X-ray systems dominate the installed base of airport baggage scanning systems for explosives detection. The majority are conveyer systems with projection line scanners. These systems can achieve a high throughput but exhibit a high false positive rate and require significant operator involvement. Systems employing computed tomography (CT) are currently being installed at a rapid rate. These can provide good discrimination of levels of xray absorption coefficient and can largely circumvent superimposition effects. Nonetheless CT measures only x-ray absorption coefficient per voxel which does not provide a means of specific material identification resulting in many false positives, and it is relatively straightforward to configure explosive materials so that they are undetectable by CT systems. Diffraction-based x-ray systems present a solution to this problem. They detect and measure atomic layer spacings in crystalline and microcrystalline materials with high sensitivity. This provides a means of specific material identification. The majority of explosive compounds are well crystallized solids at room temperature. X-ray diffraction systems using both conventional wavelength-dispersive diffraction and fixed-angle, multi-wavelength diffraction for improved throughput are described. Large-area, flat-panel x-ray detector technology coupled with an extended x-ray source will permit a full 3D volumetric x-ray diffraction scan of a bag in a single pass, (patent pending).

  15. Towards high-resolution ptychographic x-ray diffraction microscopy

    SciTech Connect

    Takahashi, Yukio; Suzuki, Akihiro; Yamauchi, Kazuto; Zettsu, Nobuyuki; Kohmura, Yoshiki; Ishikawa, Tetsuya; Senba, Yasunori; Ohashi, Haruhiko

    2011-06-01

    Ptychographic x-ray diffraction microscopy is a lensless imaging technique with a large field of view and high spatial resolution, which is also useful for characterizing the wavefront of an x-ray probe. The performance of this technique is degraded by positioning errors due to the drift between the sample and illumination optics. We propose an experimental approach for correcting the positioning errors and demonstrate success by two-dimensionally reconstructing both the wavefront of the focused x-ray beam and the complex transmissivity of the weakly scattering objects at the pixel resolution of better than 10 nm in the field of view larger than 5 {mu}m. This method is applicable to not only the observation of organelles inside cells or nano-mesoscale structures buried within bulk materials but also the characterization of probe for single-shot imaging with x-ray free electron lasers.

  16. Modern X-ray Diffraction Methods in Mineralogy and Geosciences

    SciTech Connect

    Lavina, Barbara; Dera, Przemyslaw; Downs, Robert T.

    2014-01-01

    This section is not intended to be comprehensive or detailed, because diffraction is such a vast subject. The principles of diffraction theory, however, are summarized under the assumption that the reader is familiar with basic concepts of the crystalline state. We will briefly review the basics of diffraction techniques, using laboratory and synchrotron X-ray sources and highlight some of their applications in geoscience.

  17. X-Ray-Diffraction Tests Of Irradiated Electronic Devices: I

    NASA Technical Reports Server (NTRS)

    Shaw, David C.; Lowry, Lynn E.; Barnes, Charles E.

    1993-01-01

    X-ray-diffraction tests performed on aluminum conductors in commercial HI1-507A complementary metal oxide/semiconductor (CMOS) integrated-circuit analog multiplexers, both before and after circuits exposed to ionizing radiation from Co(60) source, and after postirradiation annealing at ambient and elevated temperatures. Tests in addition to electrical tests performed to determine effects of irradiation and of postirradiation annealing on electrical operating characteristics of circuits. Investigators sought to determine whether relationship between effects of irradiation on devices and physical stresses within devices. X-ray diffraction potentially useful for nondestructive measurement of stresses.

  18. Remote X-Ray Diffraction and X-Ray Fluorescence Analysis on Planetary Surfaces

    NASA Technical Reports Server (NTRS)

    Blake, David F.; DeVincenzi, D. (Technical Monitor)

    1999-01-01

    The legacy of planetary X-ray Diffraction (XRD) and X-ray Fluorescence (XRF) began in 1960 when W. Parish proposed an XRD instrument for deployment on the moon. The instrument was built and flight qualified, but the Lunar XRD program was cancelled shortly before the first human landing in 1969. XRF chemical data have been collected in situ by surface landers on Mars (Viking 1 & 2, Pathfinder) and Venus (Venera 13 & 14). These highly successful experiments provide critical constraints on our current understanding of surface processes and planetary evolution. However, the mineralogy, which is more critical to planetary surface science than simple chemical analysis, will remain unknown or will at best be imprecisely constrained until X-ray diffraction (XRD) data are collected. Recent progress in X-ray detector technology allows the consideration of simultaneous XRD (mineralogic analysis) and high-precision XRF (elemental analysis) in systems miniaturized to the point where they can be mounted on fixed landers or small robotic rovers. There is a variety of potential targets for XRD/XRF equipped landers within the solar system, the most compelling of which are the poles of the moon, the southern highlands of Mars and Europa.

  19. Ultrafast x-ray diffraction of laser-irradiated crystals

    SciTech Connect

    Heimann, P.A.; Larsson, J.; Chang, Z.

    1997-09-01

    An apparatus has been developed for measuring time-dependent x-ray diffraction. X-ray pulses from an Advanced Light Source bend magnet are diffracted by a sagittally-focusing Si(111) crystal and then by a sample crystal, presently InSb(111). Laser pulses with 100 fs duration and a repetition rate of 1 KHz irradiate the sample inducing a phase transition. Two types of detectors are being employed: an x-ray streak camera and an avalanche photodiode. The streak camera is driven by a photoconductive switch and has a 2 ps temporal resolution determined by trigger jitter. The avalanche photodiode has high quantum efficiency and sufficient time resolution to detect single x-ray pulses in ALS two bunch or camshaft operation. A beamline is under construction dedicated for time resolved and micro-diffraction experiments. In the new beamline a toroidal mirror collects 3 mrad horizontally and makes a 1:1 image of the bend magnet source in the x-ray hutch. A laser induced phase transition has been observed in InSb occurring within 70 ps.

  20. X-Ray Diffraction Project Final Report, Fiscal Year 2006

    SciTech Connect

    Dane V. Morgan

    2006-10-01

    An x-ray diffraction diagnostic system was developed for determining real-time shock-driven lattice parameter shifts in single crystals at the gas gun at TA-IV at Sandia National Laboratories (SNL). The signal-to-noise ratio and resolution of the system were measured using imaging plates as the detector and by varying the slit width. This report includes tests of the x-ray diffraction system using a phosphor coupled to a charge-coupled device (CCD) camera by a coherent fiber-optic bundle. The system timing delay was measured with a newly installed transistor-transistor logic (TTL) bypass designed to reduce the x-ray delay time. The axial misalignment of the Bragg planes was determined with respect to the optical axis for a set of eight LiF [lithium fluoride] crystals provided by SNL to determine their suitability for gas gun experiments.

  1. Biological imaging by soft x-ray diffraction microscopy

    DOE PAGESBeta

    Shapiro, D.; Thibault, P.; Beetz, T.; Elser, V.; Howells, M.; Jacobsen, C.; Kirz, J.; Lima, E.; Miao, H.; Neiman, A. M.; et al

    2005-10-25

    We have used the method of x-ray diffraction microscopy to image the complex-valued exit wave of an intact and unstained yeast cell. The images of the freeze-dried cell, obtained by using 750-eV x-rays from different angular orientations, portray several of the cell's major internal components to 30-nm resolution. The good agreement among the independently recovered structures demonstrates the accuracy of the imaging technique. To obtain the best possible reconstructions, we have implemented procedures for handling noisy and incomplete diffraction data, and we propose a method for determining the reconstructed resolution. This work represents a previously uncharacterized application of x-ray diffractionmore » microscopy to a specimen of this complexity and provides confidence in the feasibility of the ultimate goal of imaging biological specimens at 10-nm resolution in three dimensions.« less

  2. Applied possibilities for x-ray diffraction interferometry

    NASA Astrophysics Data System (ADS)

    Raransky, M. D.; Struk, J. M.; Fodchuk, Igor M.; Shafraniuk, V. P.; Raransky, A. M.

    1995-11-01

    Among existing x ray diffraction diagnostics nonperfections of crystals the specific location take methods are based on use of x-ray dynamic diffraction effects. From them the most sensitive are based on interferention. The Pendellosung and Moire fringes methods arise in consequence of coherent dynamic interaction of wave fields in single crystals. One of the main advantages of the Moire method is the extraordinary high sensitivity to insignificant deformations of crystal lattice ((Delta) d/d approximately 10-8) and atomic planes turns ((delta) approximately 0.01'). Created by a method of x-ray diffraction Moire the unique phase magnification permits us to directly observe the nuclear rows of crystal lattice. Until recently the attention of researchers attracted, basically, precise measurements of refraction parameters and dispersion amendments to nuclear scattering amplitudes, measurement of movy with large accuracy and refinement of Avogadro number, and the creation of new multi crystal interferometers. At the same time, little opportunities of x-ray interferometry at research of crystal structure defects were used. For the first time the opportunity of definition by method x-ray diffraction Moire of Burgers vectors of individual dislocation was demonstrated by M. Hart, Christiansen has studied the series of 60 degree(s) dislocation in Si on Moire images. Tensions in Si, caused by Ar ions implantation, were defined in the work. The purpose, which the authors of given reviews pursue consists in demonstration of new opportunities of x-ray three crystal interferometry in the investigation of single and complex defects.

  3. Coherent diffraction imaging using focused hard X-rays

    NASA Astrophysics Data System (ADS)

    Kim, Sunam; Kim, Sangsoo; Lee, Su Yong; Kim, Chan; Kim, Yoonhee; Noh, Do Young; Marathe, Shashidhara; Song, Changyong; Gallagher-Jones, Marcus; Kang, Hyon Chol

    2016-05-01

    A quantitative height profile image of a silicon nano-trench structure was obtained via coherent diffraction imaging (CDI) utilizing focused X-rays at a photon energy of 5.5 keV. The ability to optimize the spatial coherence and the photon flux density of a focused X-ray beam was the key technique for achieving such technical progress at a given X-ray photon flux. This was achieved by investigating the tunability of the focused beam's optical properties and performing a CDI experiment with the focused X-rays. The relationship between the focused X-rays' optical properties ( e.g., photon flux density and spatial coherence length) and the incident beam's size, which can be tuned by adjusting the slits in front of the Fresnel zone plate (FZP) was elucidated. We also obtained a quantitative image of a nano-trench sample produced via the reconstruction process of CDI, which utilizes carefully tuned, focused X-rays.

  4. A Practical Method of Simulating X-Ray Diffraction

    ERIC Educational Resources Information Center

    Brisse, F.; Sundararajan, P. R.

    1975-01-01

    Describes an experiment in which the beam of X-rays is simulated through the use of a laser as a monochromatic light source and the crystal is replaced by photographically prepared masks. A strong diffraction pattern as large as 20 cm. can be obtained. (GS)

  5. X-Ray Diffraction Simulation Using Laser Pointers and Printers.

    ERIC Educational Resources Information Center

    Johnson, Neil E.

    2001-01-01

    Uses a laser pointer to demonstrate the analogy between optical and X-ray diffraction and a laser printer with 600 or 1200 dot resolution to create and modify arrays, print them on transparencies, and illuminate them with laser pointers. Includes 14 references. (Author/YDS)

  6. Coherent X-ray diffraction from collagenous soft tissues

    SciTech Connect

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

    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.

  7. X-ray diffraction at Matter in Extreme Conditions endstation

    NASA Astrophysics Data System (ADS)

    Xing, Zhou; Galtier, Eric; Lee, Hae Ja; Nagler, Bob

    2015-11-01

    Understanding dynamic response at the atomic level under extreme conditions is highly sought after goal to science frontiers studying warm dense matter, high pressure, geoscience, astrophysics, and planetary science. Thus it is of importance to determine the high pressure phases or metastable phases of material under shock compression. In situ X-ray diffraction technique using LCLS free electron laser X-ray is a powerful tool to record structural behavior and microstructure evolution in dense matter. Shock-induced compression and phase transitions of material lead to changes of the lattice spacing or evolution of new X-ray diffraction patterns. In this talk, we describe a platform dedicated for the X-ray diffraction studies at Matter in Extreme Conditions (MEC), which can be used to reconstruct a complete diffraction pattern from numerous detectors, optimize detector positioning in a timely manner, extract the lattice spacing profiles and texture features. This platform is available to the user community for real-time analysis. We will also discuss experimental results, using this platform, on the crystalline silicon phase transitions up to 60 GPa.

  8. Single photon energy dispersive x-ray diffraction

    SciTech Connect

    Higginbotham, Andrew; Patel, Shamim; Ciricosta, Orlando; Suggit, Matthew J.; Wark, Justin S.; Hawreliak, James A.; Collins, Gilbert W.; Coppari, Federica; Eggert, Jon H.; Tang, Henry

    2014-03-15

    With the pressure range accessible to laser driven compression experiments on solid material rising rapidly, new challenges in the diagnosis of samples in harsh laser environments are emerging. When driving to TPa pressures (conditions highly relevant to planetary interiors), traditional x-ray diffraction techniques are plagued by increased sources of background and noise, as well as a potential reduction in signal. In this paper we present a new diffraction diagnostic designed to record x-ray diffraction in low signal-to-noise environments. By utilising single photon counting techniques we demonstrate the ability to record diffraction patterns on nanosecond timescales, and subsequently separate, photon-by-photon, signal from background. In doing this, we mitigate many of the issues surrounding the use of high intensity lasers to drive samples to extremes of pressure, allowing for structural information to be obtained in a regime which is currently largely unexplored.

  9. Diffraction and Imaging Study of Imperfections of Protein Crystals with Coherent X-rays

    NASA Technical Reports Server (NTRS)

    Hu, Z. W.; Thomas, B. R.; Chernov, A. A.; Chu, Y. S.; Lai, B.

    2004-01-01

    High angular-resolution x-ray diffraction and phase contrast x-ray imaging were combined to study defects and perfection of protein crystals. Imperfections including line defects, inclusions and other microdefects were observed in the diffraction images of a uniformly grown lysozyme crystal. The observed line defects carry distinct dislocation features running approximately along the <110> growth front and have been found to originate mostly in a central growth area and occasionally in outer growth regions. 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 diffraction images. X-ray imaging and diffraction characterization of the quality of apoferritin crystals will also be discussed in the presentation.

  10. X-ray diffraction line profile analysis for defect study in Cu-1 wt.% Cr-0.1 wt.% Zr alloy

    SciTech Connect

    Kapoor, K. . E-mail: kapoork@nfc.ernet.in; Lahiri, D.; Batra, I.S.; Rao, S.V.R.; Sanyal, T.

    2005-02-15

    X-ray line profile analysis (LPA) has been used for microstructural analysis of a Cu-1 wt.% Cr-0.1 wt.% Zr alloy. Using this technique, the stacking fault probability (SFP) and stacking fault energy (SFE) has been determined for the pure Cu and the Cu-1 wt.% Cr-0.1 wt.% Zr alloy. It is observed that there is an increase in the stacking fault probability (and corresponding decrease in stacking fault energy) in case of the alloy. The increased formation of faulted regions in the Cu-1 wt.% Cr-0.1 wt.% Zr alloy is supported by the observation of extended dislocation nodes and fringe contrast due to staking faults under TEM, and higher work hardening rate in the tension test. The high thermal fatigue resistance of this alloy is attributed to decrease in the stacking fault energy by addition of Cr and Zr to Cu.

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

    DOE PAGESBeta

    Lawrence, Robert M.; Conrad, Chelsie E.; Zatsepin, Nadia A.; Grant, Thomas D.; Liu, Haiguang; James, Daniel; Nelson, Garrett; Subramanian, Ganesh; Aquila, Andrew; Hunter, Mark S.; et al

    2015-08-20

    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 a pertinent step toward determining room temperature structures from virus microcrystals that may enable time-resolved studies of enveloped viruses.

  12. Diffraction enhanced X-ray imaging of mammals crystalline lens

    NASA Astrophysics Data System (ADS)

    Antunes, A.; Hönnicke, M. G.; Safatle, A. M. V.; Cusatis, C.; Moraes Barros, P. S.; Morelhão, S. L.

    2005-08-01

    Crystalline lenses are transparent biological materials where the organization of the lens fibers can also be affected by changes at molecular level, and therefore the structure and morphology of the tissue can be correlated to the loss of transparency of the lens. In this work, internal structure of mammal lenses regarding the long-range ordering of the fibers are investigated by diffraction enhanced X-ray imaging (DEI) radiography. Moreover, DEI and absorption X-ray synchrotron radiographs for healthy and cataractous crystalline lenses are compared. Significant differences in healthy and cataractous crystalline lenses are observed.

  13. Single-pulse x-ray diffraction using polycapillary optics for in situ dynamic diffraction.

    PubMed

    Maddox, B R; Akin, M C; Teruya, A; Hunt, D; Hahn, D; Cradick, J; Morgan, D V

    2016-08-01

    Diagnostic use of single-pulse x-ray diffraction (XRD) at pulsed power facilities can be challenging due to factors such as the high flux and brightness requirements for diffraction and the geometric constraints of experimental platforms. By necessity, the x-ray source is usually positioned very close, within a few inches of the sample. On dynamic compression platforms, this puts the x-ray source in the debris field. We coupled x-ray polycapillary optics to a single-shot needle-and-washer x-ray diode source using a laser-based alignment scheme to obtain high-quality x-ray diffraction using a single 16 ns x-ray pulse with the source >1 m from the sample. The system was tested on a Mo sample in reflection geometry using 17 keV x-rays from a Mo anode. We also identified an anode conditioning effect that increased the x-ray intensity by 180%. Quantitative measurements of the x-ray focal spot produced by the polycapillary yielded a total x-ray flux on the sample of 3.3 ± 0.5 × 10(7) molybdenum Kα photons. PMID:27587130

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

    NASA Technical Reports Server (NTRS)

    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.

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

    NASA Technical Reports Server (NTRS)

    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.

  16. X-ray Diffraction from Membrane Protein Nanocrystals

    PubMed Central

    Hunter, M.S.; DePonte, D.P.; Shapiro, D.A.; Kirian, R.A.; Wang, X.; Starodub, D.; Marchesini, S.; Weierstall, U.; Doak, R.B.; Spence, J.C.H.; Fromme, P.

    2011-01-01

    Membrane proteins constitute >30% of the proteins in an average cell, and yet the number of currently known structures of unique membrane proteins is <300. To develop new concepts for membrane protein structure determination, we have explored the serial nanocrystallography method, in which fully hydrated protein nanocrystals are delivered to an x-ray beam within a liquid jet at room temperature. As a model system, we have collected x-ray powder diffraction data from the integral membrane protein Photosystem I, which consists of 36 subunits and 381 cofactors. Data were collected from crystals ranging in size from 100 nm to 2 μm. The results demonstrate that there are membrane protein crystals that contain <100 unit cells (200 total molecules) and that 3D crystals of membrane proteins, which contain <200 molecules, may be suitable for structural investigation. Serial nanocrystallography overcomes the problem of x-ray damage, which is currently one of the major limitations for x-ray structure determination of small crystals. By combining serial nanocrystallography with x-ray free-electron laser sources in the future, it may be possible to produce molecular-resolution electron-density maps using membrane protein crystals that contain only a few hundred or thousand unit cells. PMID:21190672

  17. Discovery and development of x-ray diffraction

    NASA Astrophysics Data System (ADS)

    Jeong, Yeuncheol; Yin, Ming; Datta, Timir

    2013-03-01

    In 1912 Max Laue at University of Munich reasoned x-rays to be short wavelength electromagnetic waves and figured interference would occur when scattered off crystals. Arnold Sommerfeld, W. Wien, Ewald and others, raised objections to Laue's idea, but soon Walter Friedrich succeeded in recording x-ray interference patterns off copper sulfate crystals. But the Laue-Ewald's 3-dimensional formula predicted excess spots. Fewer spots were observed. William Lawrence Bragg then 22 year old studying at Cambridge University heard the Munich results from father William Henry Brag, physics professor at Univ of Leeds. Lawrence figured the spots are 2-d interference of x-ray wavelets reflecting off successive atomic planes and derived a simple eponymous equation, the Bragg equation d*sin(theta) = n*lamda. 1913 onward the Braggs dominated the crystallography. Max Laue was awarded the physics Nobel in 1914 and the Braggs shared the same in 1915. Starting with Rontgen's first ever prize in 1901, the importance of x-ray techniques is evident from the four out of a total 16 physics Nobels between 1901-1917. We will outline the historical back ground and importance of x-ray diffraction giving rise to techniques that even in 2013, remain work horses in laboratories all over the globe.

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

    PubMed Central

    Landahl, Eric C.; Antipova, Olga; Bongaarts, Angela; Barrea, Raul; Berry, Robert; Binder, Lester I.; Irving, Thomas; Orgel, Joseph; Vana, Laurel

    2011-01-01

    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 labs have done previously. We demonstrate that thiazine red-enhanced regions within the tissue show periodic structure in x-ray diffraction that is not observed in healthy tissue. One observed periodicity (4.2 Å) is characteristic of cross-beta sheet structure, consistent with previous results from powder diffraction studies performed on purified, dried tau protein. PMID:21876609

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

    PubMed

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

    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 labs have done previously. We demonstrate that thiazine red-enhanced regions within the tissue show periodic structure in x-ray diffraction that is not observed in healthy tissue. One observed periodicity (4.2 Å) is characteristic of cross-beta sheet structure, consistent with previous results from powder diffraction studies performed on purified, dried tau protein. PMID:21876609

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

    NASA Astrophysics Data System (ADS)

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

    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 Å) is characteristic of cross-beta sheet structure, consistent with previous results from powder diffraction studies performed on purified, dried tau protein.

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

    SciTech Connect

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

    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.

  2. Anomalous X-ray diffraction with soft X-ray synchrotron radiation.

    PubMed

    Carpentier, P; Berthet-Colominas, C; Capitan, M; Chesne, M L; Fanchon, E; Lequien, S; Stuhrmann, H; Thiaudière, D; Vicat, J; Zielinski, P; Kahn, R

    2000-07-01

    Anomalous diffraction with soft X-ray synchrotron radiation opens new possibilities in protein crystallography and materials science. Low-Z elements like silicon, phosphorus, sulfur and chlorine become accessible as new labels in structural studies. Some of the heavy elements like uranium exhibit an unusually strong dispersion at their M(V) absorption edge (lambdaMV = 3.497 A, E(MV) = 3545 eV) and so does thorium. Two different test experiments are reported here showing the feasibility of anomalous X-ray diffraction at long wavelengths with a protein containing uranium and with a salt containing chlorine atoms. With 110 electrons the anomalous scattering amplitude of uranium exceeds by a factor of 4 the resonance scattering of other strong anomalous scatterers like that of the lanthanides at their L(III) edge. The resulting exceptional phasing power of uranium is most attractive in protein crystallography using the multi-wavelength anomalous diffraction (MAD) method. The anomalous dispersion of an uranium derivative of asparaginyl-tRNA synthetase (hexagonal unit cell; a = 123.4 A, c = 124.4 A) has been measured for the first time at 4 wavelengths near the M(V) edge using the beamline ID1 of ESRF (Grenoble, France). The present set up allowed to measure only 30% of the possible reflections at a resolution of 4 A, mainly because of the low sensitivity of the CCD detector. In the second experiment, the dispersion of the intensity of 5 X-ray diffraction peaks from pentakismethylammonium undecachlorodibismuthate (PMACB, orthorhombic unit cell; a = 13.003 A, b = 14.038 A, c = 15.450 A) has been measured at 30 wavelengths near the K absorption edge of chlorine (lambdaK = 4.397 A, EK= 2819.6 eV). All reflections within the resolution range from 6.4 A to 3.4 A expected in the 20 degree scan were observed. The chemical state varies between different chlorine atoms of PMACB, and so does the dispersion of different Bragg peaks near the K-edge of chlorine. The results reflect

  3. Focal construct geometry for high intensity energy dispersive x-ray diffraction based on x-ray capillary optics.

    PubMed

    Li, Fangzuo; Liu, Zhiguo; Sun, Tianxi; Jiang, Bowen; Zhu, Yu

    2016-03-14

    We presented a focal construct geometry (FCG) method for high intensity energy dispersive X-ray diffraction by utilizing a home-made ellipsoidal single-bounce capillary (ESBC) and a polycapillary parallel X-ray lens (PPXRL). The ESBC was employed to focus the X-rays from a conventional laboratory source into a small focal spot and to produce an annular X-ray beam in the far-field. Additionally, diffracted polychromatic X-rays were confocally collected by the PPXRL attached to a stationary energy-resolved detector. Our FCG method based on ESBC and PPXRL had achieved relatively high intensity diffraction peaks and effectively narrowed the diffraction peak width which was helpful in improving the potential d-spacing resolution for material phase analysis. PMID:26979685

  4. Focal construct geometry for high intensity energy dispersive x-ray diffraction based on x-ray capillary optics

    NASA Astrophysics Data System (ADS)

    Li, Fangzuo; Liu, Zhiguo; Sun, Tianxi; Jiang, Bowen; Zhu, Yu

    2016-03-01

    We presented a focal construct geometry (FCG) method for high intensity energy dispersive X-ray diffraction by utilizing a home-made ellipsoidal single-bounce capillary (ESBC) and a polycapillary parallel X-ray lens (PPXRL). The ESBC was employed to focus the X-rays from a conventional laboratory source into a small focal spot and to produce an annular X-ray beam in the far-field. Additionally, diffracted polychromatic X-rays were confocally collected by the PPXRL attached to a stationary energy-resolved detector. Our FCG method based on ESBC and PPXRL had achieved relatively high intensity diffraction peaks and effectively narrowed the diffraction peak width which was helpful in improving the potential d-spacing resolution for material phase analysis.

  5. Coherent X-ray diffraction from collagenous soft tissues

    PubMed Central

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

    2009-01-01

    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. PMID:19706395

  6. Fabricating Blazed Diffraction Gratings by X-Ray Lithography

    NASA Technical Reports Server (NTRS)

    Mouroulis, Pantazis; Hartley, Frank; Wilson, Daniel

    2004-01-01

    Gray-scale x-ray lithography is undergoing development as a technique for fabricating blazed diffraction gratings. As such, gray-scale x-ray lithography now complements such other grating-fabrication techniques as mechanical ruling, holography, ion etching, laser ablation, laser writing, and electron-beam lithography. Each of these techniques offers advantages and disadvantages for implementing specific grating designs; no single one of these techniques can satisfy the design requirements for all applications. Gray-scale x-ray lithography is expected to be advantageous for making gratings on steeper substrates than those that can be made by electron-beam lithography. This technique is not limited to sawtooth groove profiles and flat substrates: various groove profiles can be generated on arbitrarily shaped (including highly curved) substrates with the same ease as sawtooth profiles can be generated on flat substrates. Moreover, the gratings fabricated by this technique can be made free of ghosts (spurious diffraction components attributable to small spurious periodicities in the locations of grooves). The first step in gray-scale x-ray lithography is to conformally coat a substrate with a suitable photoresist. An x-ray mask (see Figure 1) is generated, placed between the substrate and a source of collimated x-rays, and scanned over the substrate so as to create a spatial modulation in the exposure of the photoresist. Development of the exposed photoresist results in a surface corrugation that corresponds to the spatial modulation and that defines the grating surface. The grating pattern is generated by scanning an appropriately shaped x-ray area mask along the substrate. The mask example of Figure 1 would generate a blazed grating profile when scanned in the perpendicular direction at constant speed, assuming the photoresist responds linearly to incident radiation. If the resist response is nonlinear, then the mask shape can be modified to account for the

  7. The effect of silica on polymorphic precipitation of calcium carbonate: an on-line energy-dispersive X-ray diffraction (EDXRD) study

    NASA Astrophysics Data System (ADS)

    Kellermeier, Matthias; Glaab, Fabian; Klein, Regina; Melero-García, Emilio; Kunz, Werner; García-Ruiz, Juan Manuel

    2013-07-01

    Calcium carbonate is the most abundant biomineral and a compound of great industrial importance. Its precipitation from solution has been studied extensively and was often shown to proceed via distinct intermediate phases, which undergo sequential transformations before eventually yielding the stable crystalline polymorph, calcite. In the present work, we have investigated the crystallisation of calcium carbonate in a time-resolved and non-invasive manner by means of energy-dispersive X-ray diffraction (EDXRD) using synchrotron radiation. In particular, the role of silica as a soluble additive during the crystallisation process was examined. Measurements were carried out at different temperatures (20, 50 and 80 °C) and various silica concentrations. Experiments conducted in the absence of silica reflect the continuous conversion of kinetically formed metastable polymorphs (vaterite and aragonite) to calcite and allow for quantifying the progress of transformation. Addition of silica induced remarkable changes in the temporal evolution of polymorphic fractions existing in the system. Essentially, the formation of calcite was found to be accelerated at 20 °C, whereas marked retardation or complete inhibition of phase transitions was observed at higher temperatures. These findings are explained in terms of a competition between the promotional effect of silica on calcite growth rates and kinetic stabilisation of vaterite and aragonite due to adsorption (or precipitation) of silica on their surfaces, along with temperature-dependent variations of silica condensation rates. Data collected at high silica concentrations indicate the presence of an amorphous phase over extended frames of time, suggesting that initially generated ACC particles are progressively stabilised by silica. Our results may have important implications for CaCO3 precipitation scenarios in both geochemical and industrial settings, where solution silicate is omnipresent, as well as for CO2

  8. Coherent x-ray diffraction from quantum dots

    SciTech Connect

    Vartanyants, I.A.; Robinson, I. K.; Onken, J.D.; Pfeifer, M.A.; Williams, G.J.; Pfeiffer, F.; Metzger, H.; Zhong, Z.; Bauer, G.

    2005-06-15

    Coherent x-ray diffraction is a new experimental method for studying perfect and imperfect crystals. Instead of incoherent averaging, a coherent sum of amplitudes produces a coherent diffraction pattern originating from the real space arrangement of the sample. We applied this method for studying quantum dot samples that were specially fabricated GeSi islands of nanometer size and in a regular array embedded into a Si substrate. A coherent beam was focused by special Kirkpatric-Baez optics to a micrometer size. In the experiment it was observed that such a microfocused coherent beam produced coherent diffraction pattern with Bragg spots and broad diffuse maxima. The diffuse peak breaks up into a fine speckle pattern. The grazing incidence diffraction pattern has a typical shape resulting from the periodic array of identical islands. We used this diffraction pattern to reconstruct the average shape of the islands using a model independent approach.

  9. X-ray diffraction computed tomography: a survey and description

    NASA Astrophysics Data System (ADS)

    Kleuker, Ulf

    1997-10-01

    Coherently scattered x-rays are mainly confined to a forward peaked cone, which exhibits, due to their coherence, structural information of the atomic arrangement in the sample. Coherent scattering in amorphous materials, which are of random short range order, therefore results in board diffraction ring patter, whereas crystalline substance show more confined diffraction rings or even Brag spots. X-ray diffraction computed tomography (XRDCT) reconstructs the intensities diffracted from extended objects on a square image grid and thus retrieves the local structure. A short survey is presented about what information can be extracted from diffraction experiments. Hereby a new method is proposed to use the Rietveld refinement for quantitative XRDCT. Also the possible use of XRDCT to reconstruct the spatial distribution of preferred orientation axis is suggested. An imaging system for XRDCT, consisting of a medical image intensifier tube and CCD readout system, is presented, which includes a modified beam stop for recording the intensity of the transmitted beam. Depending on the application this imaging system cam work in first generation or second generation tomography mode. Furthermore a new approach for the reconstruction of the differential coherent cross-section is proposed. It includes an absorption correction based on weighted sinograms. The introduced reconstruction strategy is elucidated by experimental result from a simple phantom. The measured data also validate the simulation program, written to study more complex phantoms under different experimental conditions. Finally possible applications in medical and material science are discussed. A design for a mammography setup using x-ray diffraction is presented.

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

    NASA Astrophysics Data System (ADS)

    Mendoza Cuevas, Ariadna; Perez Gravie, Homero

    2011-03-01

    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.

  11. X-ray diffraction of strained muscle fibers in rigor.

    PubMed Central

    Naylor, G R; Podolsky, R J

    1981-01-01

    The effect of strain on the equatorial x-ray diffraction pattern of glycerinated rabbit psoas fibers was studied in the rigor (ATP free) state. Strains between 30 and 100 A per half sarcomere, measured directly by laser diffraction, did not change the intensity ratio, (10)/ . (11). Because the intensity ratio depends on the distribution of mass within the myofilament lattice, the negative result indicates that strain does not change the angle of attachment of the subfragment 1 (S1) moiety of the myosin molecule to the actin filament. The effect of strain on the ordering of the actin filaments also was considered and judged to be negligible. Images PMID:6946493

  12. Quantum-dot-array diffraction grating with single order diffraction property for soft x-ray region

    SciTech Connect

    Kuang Longyu; Wang Chuanke; Wang Zhebin; Cao Leifeng; Liu Shenye; Ding Yongkun; Zhu Xiaoli; Xie Changqing

    2010-07-15

    A gold transmission grating is used routinely to disperse the x-ray spectrum at the Z soft x-ray facility to measure the spectrum and temporal history of the absolute soft x-ray power emitted from z-pinch and hohlraum radiation sources. A quantum-dot-array diffraction grating (QDADG) of 250 lines/mm for soft x-ray is designed and fabricated for the first time according to the principle of binary sinusoidal transmission grating. The diffraction efficiencies of the grating are measured in the 150-300 eV photon energy range on the Beamline 3W1B of Beijing Synchrotron Radiation Facility. This article describes the basic concept and calibration techniques and presents calibration results. It is shown that the 250 lines/mm QDADG can be used to disperse light without higher-order diffractions in soft x-ray range, and the diffraction efficiencies of this grating are nearly constant (about 25%), which is beneficial in the spectrum analysis.

  13. Quantum-dot-array diffraction grating with single order diffraction property for soft x-ray region

    NASA Astrophysics Data System (ADS)

    Kuang, Longyu; Wang, Chuanke; Wang, Zhebin; Cao, Leifeng; Zhu, Xiaoli; Xie, Changqing; Liu, Shenye; Ding, Yongkun

    2010-07-01

    A gold transmission grating is used routinely to disperse the x-ray spectrum at the Z soft x-ray facility to measure the spectrum and temporal history of the absolute soft x-ray power emitted from z-pinch and hohlraum radiation sources. A quantum-dot-array diffraction grating (QDADG) of 250 lines/mm for soft x-ray is designed and fabricated for the first time according to the principle of binary sinusoidal transmission grating. The diffraction efficiencies of the grating are measured in the 150-300 eV photon energy range on the Beamline 3W1B of Beijing Synchrotron Radiation Facility. This article describes the basic concept and calibration techniques and presents calibration results. It is shown that the 250 lines/mm QDADG can be used to disperse light without higher-order diffractions in soft x-ray range, and the diffraction efficiencies of this grating are nearly constant (about 25%), which is beneficial in the spectrum analysis.

  14. Quantum-dot-array diffraction grating with single order diffraction property for soft x-ray region.

    PubMed

    Kuang, Longyu; Wang, Chuanke; Wang, Zhebin; Cao, Leifeng; Zhu, Xiaoli; Xie, Changqing; Liu, Shenye; Ding, Yongkun

    2010-07-01

    A gold transmission grating is used routinely to disperse the x-ray spectrum at the Z soft x-ray facility to measure the spectrum and temporal history of the absolute soft x-ray power emitted from z-pinch and hohlraum radiation sources. A quantum-dot-array diffraction grating (QDADG) of 250 lines/mm for soft x-ray is designed and fabricated for the first time according to the principle of binary sinusoidal transmission grating. The diffraction efficiencies of the grating are measured in the 150-300 eV photon energy range on the Beamline 3W1B of Beijing Synchrotron Radiation Facility. This article describes the basic concept and calibration techniques and presents calibration results. It is shown that the 250 lines/mm QDADG can be used to disperse light without higher-order diffractions in soft x-ray range, and the diffraction efficiencies of this grating are nearly constant (about 25%), which is beneficial in the spectrum analysis. PMID:20687723

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

    PubMed Central

    Lawrence, Robert M.; Conrad, Chelsie E.; Zatsepin, Nadia A.; Grant, Thomas D.; Liu, Haiguang; James, Daniel; Nelson, Garrett; Subramanian, Ganesh; Aquila, Andrew; Hunter, Mark S.; Liang, Mengning; Boutet, Sébastien; Coe, Jesse; Spence, John C. H.; Weierstall, Uwe; Liu, Wei; Fromme, Petra; Cherezov, Vadim; Hogue, Brenda G.

    2015-01-01

    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. PMID:26798819

  16. Line-Source Based X-Ray Tomography

    PubMed Central

    Bharkhada, Deepak; Yu, Hengyong; Liu, Hong; Plemmons, Robert; Wang, Ge

    2009-01-01

    Current computed tomography (CT) scanners, including micro-CT scanners, utilize a point x-ray source. As we target higher and higher spatial resolutions, the reduced x-ray focal spot size limits the temporal and contrast resolutions achievable. To overcome this limitation, in this paper we propose to use a line-shaped x-ray source so that many more photons can be generated, given a data acquisition interval. In reference to the simultaneous algebraic reconstruction technique (SART) algorithm for image reconstruction from projection data generated by an x-ray point source, here we develop a generalized SART algorithm for image reconstruction from projection data generated by an x-ray line source. Our numerical simulation results demonstrate the feasibility of our novel line-source based x-ray CT approach and the proposed generalized SART algorithm. PMID:19436708

  17. X-ray topography using the forward transmitted beam under multiple-beam diffraction conditions

    NASA Astrophysics Data System (ADS)

    Tsusaka, Y.; Takeda, S.; Takano, H.; Yokoyama, K.; Kagoshima, Y.; Matsui, J.

    2016-02-01

    X-ray topographs are taken for a sapphire wafer with the [0001] surface normal, as an example, by forward transmitted synchrotron x-ray beams combined with two-dimensional electronic arrays in the x-ray detector having a spatial resolution of 1 μm. They exhibit no shape deformation and no position shift of the dislocation lines on the topographs. Since the topography is performed under multiple-beam diffraction conditions, the topographic images of a single diffraction (two-wave approximation condition) or plural diffractions (six-wave approximation condition) can be recorded without large specimen position changes. As usual Lang topographs, it is possible to determine the Burgers vector of each dislocation line. Because of high parallelism of the incoming x-rays and linear sensitivity of the electronic arrays to the incident x-rays, the present technique can be used to visualize individual dislocations in single crystals of the dislocation density as high as 1 × 105 cm-2.

  18. Diffraction imaging of crystals with focused x-ray beams

    SciTech Connect

    Kazimirov, A.; Kohn, V. G.; Cai, Z.-H.

    2010-06-01

    We describe an imaging technique based on diffraction of a focused x-ray beam in crystals. A focused beam is formed by a zone plate and Bragg diffracted from a crystalline sample positioned between the zone plate and the focus. The intensity pattern is recorded by a high-resolution charge-coupled-device detector placed in the focus. Diffraction images recorded from perfect Si and GaAs crystals for various reflections demonstrate the broadening of the focused beam due to a finite scattering length. The images from semiconductor epitaxial films and heterostructures show additional peaks originating from the interfaces with their spatial position corresponding to the depth from the surface. Diffraction images from isolated defects in Si crystal demonstrate capabilities to study bulk defects. Theoretical simulations for perfect crystals show excellent agreement with experiments. We demonstrate that the new imaging technique is depth sensitive and combines structural sensitivity of traditional x-ray topography methods with spatial in-plane resolution provided by focusing.

  19. A Computational Algorithm to Produce Virtual X-ray and Electron Diffraction Patterns from Atomistic Simulations

    NASA Astrophysics Data System (ADS)

    Coleman, Shawn P.; Sichani, Mehrdad M.; Spearot, Douglas E.

    2014-03-01

    Electron and x-ray diffraction are well-established experimental methods used to explore the atomic scale structure of materials. In this work, a computational algorithm is developed to produce virtual electron and x-ray diffraction patterns directly from atomistic simulations. This algorithm advances beyond previous virtual diffraction methods by using a high-resolution mesh of reciprocal space that eliminates the need for a priori knowledge of the crystal structure being modeled or other assumptions concerning the diffraction conditions. At each point on the reciprocal space mesh, the diffraction intensity is computed via explicit computation of the structure factor equation. To construct virtual selected-area electron diffraction patterns, a hemispherical slice of the reciprocal lattice mesh lying on the surface of the Ewald sphere is isolated and viewed along a specified zone axis. X-ray diffraction line profiles are created by binning the intensity of each reciprocal lattice point by its associated scattering angle, effectively mimicking powder diffraction conditions. The virtual diffraction algorithm is sufficiently generic to be applied to atomistic simulations of any atomic species. In this article, the capability and versatility of the virtual diffraction algorithm is exhibited by presenting findings from atomistic simulations of <100> symmetric tilt Ni grain boundaries, nanocrystalline Cu models, and a heterogeneous interface formed between α-Al2O3 (0001) and γ-Al2O3 (111).

  20. Identifications studies of Lauha Bhasma by X-ray diffraction and X-ray fluorescence

    PubMed Central

    Bhargava, S. C.; Reddy, K. R. C; Sastry, G. V. S

    2012-01-01

    Procedures for preparation of Lauha Bhasma are described in ancient texts of Ayurveda. These procedures also begin with different source material for iron such as Teekshna Lauha and Kanta Lauha etc. In the present study, we have selected different source materials viz. magnetite iron ore for Kanta Lauha and pure (Armco grade) iron turnings for Teekshna Lauha. The standard procedures of preparation of Lauha Bhasma are carried out in identical conditions for these two raw materials. The final product from the Puta are characterized by using X-ray diffraction and X-ray fluorescence spectroscopy to understanding the crystallographic form or forms of iron oxides and their composition at the end of each Puta. The iron content at the end of repeated Putas (18 for Kanta Lauha and 20 for Teekshna Lauha) have shown a decrease in case of Teekshna Lauha since the starting material is pure iron while it showed only marginal decreases in the case of Kanta Lauha because the Fe3O4 of magnetite is undergoing oxidation to Fe2O3. The trace elements remain within the Bhasma in the form of various oxides of Si, Al, Ca, etc. PMID:23049200

  1. Identifications studies of Lauha Bhasma by X-ray diffraction and X-ray fluorescence.

    PubMed

    Bhargava, S C; Reddy, K R C; Sastry, G V S

    2012-01-01

    Procedures for preparation of Lauha Bhasma are described in ancient texts of Ayurveda. These procedures also begin with different source material for iron such as Teekshna Lauha and Kanta Lauha etc. In the present study, we have selected different source materials viz. magnetite iron ore for Kanta Lauha and pure (Armco grade) iron turnings for Teekshna Lauha. The standard procedures of preparation of Lauha Bhasma are carried out in identical conditions for these two raw materials. The final product from the Puta are characterized by using X-ray diffraction and X-ray fluorescence spectroscopy to understanding the crystallographic form or forms of iron oxides and their composition at the end of each Puta. The iron content at the end of repeated Putas (18 for Kanta Lauha and 20 for Teekshna Lauha) have shown a decrease in case of Teekshna Lauha since the starting material is pure iron while it showed only marginal decreases in the case of Kanta Lauha because the Fe(3)O(4) of magnetite is undergoing oxidation to Fe(2)O(3). The trace elements remain within the Bhasma in the form of various oxides of Si, Al, Ca, etc. PMID:23049200

  2. Quasi-sinusoidal single-order diffraction transmission grating used in x-ray spectroscopy.

    PubMed

    Kuang, Longyu; Cao, Leifeng; Zhu, Xiaoli; Wu, Shunchao; Wang, Zhebin; Wang, Chuanke; Liu, Shenye; Jiang, Shaoen; Yang, Jiamin; Ding, Yongkun; Xie, Changqing; Zheng, Jian

    2011-10-15

    A novel design of quasi-sinusoidal single-order diffraction transmission grating (QSTG) is proposed, which can achieve a line density up to thousands line/millimeter as that of traditional transmission gratings with the current level of nanofabrication technique. We fabricate a 1000 line/mm QSTG using the new design approach, and display the calibration results of such QSTG on the soft x-ray beam of synchrotron radiation. PMID:22002350

  3. High pressure x-ray diffraction techniques with synchrotron radiation

    NASA Astrophysics Data System (ADS)

    Jing, Liu

    2016-07-01

    This article summarizes the developments of experimental techniques for high pressure x-ray diffraction (XRD) in diamond anvil cells (DACs) using synchrotron radiation. Basic principles and experimental methods for various diffraction geometry are described, including powder diffraction, single crystal diffraction, radial diffraction, as well as coupling with laser heating system. Resolution in d-spacing of different diffraction modes is discussed. More recent progress, such as extended application of single crystal diffraction for measurements of multigrain and electron density distribution, time-resolved diffraction with dynamic DAC and development of modulated heating techniques are briefly introduced. The current status of the high pressure beamline at BSRF (Beijing Synchrotron Radiation Facility) and some results are also presented. Project supported by the National Natural Science Foundation of China (Grant Nos. 10875142, 11079040, and 11075175). The 4W2 beamline of BSRF was supported by the Chinese Academy of Sciences (Grant Nos. KJCX2-SW-N20, KJCX2-SW-N03, and SYGNS04).

  4. Soft x-ray coherent diffraction imaging on magnetic nanostructures

    NASA Astrophysics Data System (ADS)

    Shi, Xiaowen; Lee, James; Mishra, Shrawan; Parks, Daniel; Tyliszczak, Tolek; Shapiro, David; Roy, Sujoy; Kevan, Steve; Stxm Team At Als Collaboration; Soft X-Ray Microscopy Group At Als Collaboration; Soft X-ray scattering at ALS, LBL Team

    2014-03-01

    Coherent soft X-rays diffraction imaging enable coherent magnetic resonance scattering at transition metal L-edge to be probed so that magnetic domains could be imaged with very high spatial resolution with phase contrast, reaching sub-10nm. One of the overwhelming advantages of using coherent X-rays is the ability to resolve phase contrast images with linearly polarized light with both phase and absorption contrast comparing to real-space imaging, which can only be studied with circularly polarized light with absorption contrast only. Here we report our first results on high-resolution of magnetic domains imaging of CoPd multilayer thin film with coherent soft X-ray ptychography method. We are aiming to resolve and understand magnetic domain wall structures with the highest obtainable resolution here at Advanced Light Source. In principle types of magnetic domain walls could be studied so that Neel or Bloch walls can be distinguished by imaging. This work at LBNL was supported by the Director, Office of Science, Office of Basic Energy Sciences, of the US Department of Energy (contract no. DE-AC02- 05CH11231).

  5. X-ray diffraction from hexagonal dislocation networks

    NASA Astrophysics Data System (ADS)

    Kopp, Viktor S.; Kaganer, Vladimir M.

    2014-10-01

    We built the honeycomb networks of misfit dislocations by combining angular dislocations. Two different models of the disorder in the dislocation network are explored, the random shifts of nodes and random sources of distortion. The displacement fields of disturbed dislocation networks are used to simulate the X-ray diffraction patterns by Monte Carlo method. We find that substantial disorder is needed for random shifts to be experimentally observable as diffuse scattering. The model of random distortion sources produces comparable diffuse scattering with the dislocation network looking closer to the initial perfect structure. The diffraction patterns due to distorted honeycomb dislocation networks are compared with the ones due to triangular networks of straight dislocations. The disorder parameters of the latter networks can be chosen to produce diffraction patterns similar to the former.

  6. A curved razor-blade proportional counter for x-ray diffraction

    SciTech Connect

    Duijn, J.H.; Van Eijk, C.W.E.; Hollander, R.W.; Marx, R.

    1986-02-01

    A curved one-dimensional position-sensitive proportional detector (PSD) has been developed for powder diffraction studies. A curved ''razor-blade'' functions as anode. Cathode-strip readout gives position sensitivity. With individual strip readout, XeCO/sub 2/ and Cu k..cap alpha.. X-rays the authors obtained for the width of a diffraction line (FWHM) 200 ..mu..m.

  7. X-ray Mirage Diffraction and Its Interference Fringes

    NASA Astrophysics Data System (ADS)

    Fukamachi, Tomoe; Kawamura, Takaaki

    When the dispersion angle of X-rays in a perfect crystal is large, interference fringes are observed between the beams in the Bragg-Laue mode and Bragg-Bragg-Laue mode in the emitted beams from the lateral surface. If the crystal is weakly bent, X-rays propagate along a path of hyperbolic form and are diffracted from the incident surface, which is called mirage diffraction. Under the condition, mirage interference fringes between two mirage diffraction beams are observed not only from the incident surface but also from the lateral surface. Two approaches are proposed to determine strain parameters in the bent crystal by using the mirage interference fringes from the incident surface or the lateral surface. In one approach, the third peak of the mirage interference fringes is used. In the other, the region is used where no direct beam reaches to the lateral surface. The resultant strain parameters determined by the two approaches show excellent agreement. Some characteristics and advantages of using mirage interference fringes are discussed.

  8. X-ray diffraction studies of shocked lunar analogs

    NASA Technical Reports Server (NTRS)

    Hanss, R. E.

    1979-01-01

    The X-ray diffraction experiments on shocked rock and mineral analogs of particular significance to lunar geology are described. Materials naturally shocked by meteorite impact, nuclear-shocked, or artificially shocked in a flat plate accelerator were utilized. Four areas were outlined for investigation: powder diffractometer studies of shocked single crystal silicate minerals (quartz, orthoclase, oligoclase, pyroxene), powder diffractometer studies of shocked polycrystalline monomineralic samples (dunite), Debye-Scherrer studies of single grains of shocked granodiorite, and powder diffractometer studies of shocked whole rock samples. Quantitative interpretation of peak shock pressures experienced by materials found in lunar or terrestrial impact structures is presented.

  9. X-Ray Diffraction of Heterogeneous Solid Hydrogen - Oral Presentation

    SciTech Connect

    Levitan, Abraham

    2015-08-24

    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.

  10. Ultrafast X-Ray Diffraction of Heterogeneous Solid Hydrogen

    SciTech Connect

    Levitan, Abraham

    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.

  11. The three dimensional X-ray diffraction technique

    SciTech Connect

    Jensen, D. Juul; Poulsen, H.F.

    2012-10-24

    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 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.

  12. The three dimensional X-ray diffraction technique

    SciTech Connect

    Jensen, D. Juul; Poulsen, H.F.

    2012-10-15

    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 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.

  13. High Pressure X-ray Diffraction Study of Potassium Azide

    SciTech Connect

    C Ji; F Zhang; D Hong; H Zhu; J Wu; M Chyu; V Levitas; Y Ma

    2011-12-31

    Crystal structure and compressibility of potassium azide was investigated by in-situ synchrotron powder X-ray diffraction in a diamond anvil cell at room temperature up to 37.7 GPa. In the body-centered tetragonal (bct) phase, an anisotropic compressibility was observed with greater compressibility in the direction perpendicular to the plane containing N{sub 3}{sup -} ions than directions within that plane. The bulk modulus of the bct phase was determined to be 18.6(7) GPa. A pressure-induced phase transition may occur at 15.5 GPa.

  14. Volumetric measurement of residual stress using high energy x-ray diffraction

    NASA Astrophysics Data System (ADS)

    Whitesell, R.; McKenna, A.; Wendt, S.; Gray, J.

    2016-02-01

    We present results and recent developments from our laboratory, bench-top high energy x-ray diffraction system (HEXRD), between diffraction energies 50 and 150 KeV, to measure internal strain of moderately sized objects. Traditional x-ray strain measurements are limited to a few microns depth due to the use of Cu Kα1 Mo Kα1 radiation. The use of high energy x-rays for volumetric measurements of strain is typically the domain of synchrotron sources. We discuss the use of industrial 320kVp tube sources to generate a brighter x-ray beam along with a method using the intrinsic 43 eV width of the Kα1 characteristic peak of tungsten to measure volumetric strains in a number of industrially relevant materials. We will present volumetric strain measurements from two examples, first, additive manufacturing (AM) parts with various build configurations and, secondly, residual strain depth profiles from shot peened surface treatments. The spatial resolution of these depth profiles is ˜75 microns. The development of a faster method as compared to energy dispersive or θ-2θ scans is based on the intensity variation measurement of the strain using the aforementioned 43 eV characteristic tungsten kα line. We will present recent results on the development of this new tool and on x-ray diffraction measurements at high energy.

  15. Anomalous X-ray Diffraction Studies for Photovoltaic Applications

    SciTech Connect

    Not Available

    2011-06-22

    Anomalous X-ray Diffraction (AXRD) has become a useful technique in characterizing bulk and nanomaterials as it provides specific information about the crystal structure of materials. In this project we present the results of AXRD applied to materials for photovoltaic applications: ZnO loaded with Ga and ZnCo{sub 2}O{sub 4} spinel. The X-ray diffraction data collected for various energies were plotted in Origin software. The peaks were fitted using different functions including Pseudo Voigt, Gaussian, and Lorentzian. This fitting provided the integrated intensity data (peaks area values), which when plotted as a function of X-ray energies determined the material structure. For the first analyzed sample, Ga was not incorporated into the ZnO crystal structure. For the ZnCo{sub 2}O{sub 4} spinel Co was found in one or both tetrahedral and octahedral sites. The use of anomalous X-ray diffraction (AXRD) provides element and site specific information for the crystal structure of a material. This technique lets us correlate the structure to the electronic properties of the materials as it allows us to probe precise locations of cations in the spinel structure. What makes it possible is that in AXRD the diffraction pattern is measured at a number of energies near an X-ray absorption edge of an element of interest. The atomic scattering strength of an element varies near its absorption edge and hence the total intensity of the diffraction peak changes by changing the X-ray energy. Thus AXRD provides element specific structural information. This method can be applied to both crystalline and liquid materials. One of the advantages of AXRD in crystallography experiments is its sensitivity to neighboring elements in the periodic tables. This method is also sensitive to specific crystallographic phases and to a specific site in a phase. The main use of AXRD in this study is for transparent conductors (TCs) analysis. TCs are considered to be important materials because of their

  16. DiffractX: A Simulation Toolbox for Diffractive X-ray Optics

    NASA Astrophysics Data System (ADS)

    Selin, M.; Bertilson, M.; Nilsson, D.; von Hofsten, O.; Hertz, H. M.; Vogt, U.

    2011-09-01

    X-ray wavefront propagation is a powerful technique when simulating the performance of x-ray optical components. Using various numerical methods, interesting parameters such as focusing capability and efficiency can be investigated. Here we present the toolbox DiffractX, implemented in MATLAB. It contains many different wave propagation methods for the simulation of diffractive x-ray optics, including Fresnel propagation, the finite difference method (FDM), the thin object approximation, the rigorous coupled wave theory (RCWT), and the finite element method (FEM). All tools are accessed through a graphical interface, making the design of simulations fast and intuitive, even for users with little or no programming experience. The tools have been utilized to characterize realistic as well as idealized optical components. This will aid further developments of diffractive x-ray optics.

  17. X-ray Diffraction Studies of Striated Muscles

    SciTech Connect

    Squire, J.M.; Knupp, C.; Roessle, M.; Al-Khayat, H.A.; Irving, T.C.; Eakins, F.; Mok, N.-S.; Harford, J.J.; Reedy, M.K.

    2006-04-24

    In this short review a number of recent X-ray diffraction results on the highly ordered striated muscles in insects and in bony fish have been briefly described. What is clear is that this technique applied to muscles which are amenable to rigorous analysis, taken together with related data from other sources (e.g. protein crystallography, biochemistry, mechanics, computer modelling) can provide not only the best descriptions yet available on the myosin head organisations on different myosin filaments in the relaxed state, but can also show the sequence of molecular events that occurs in the contractile cycle, and may also help to explain such phenomena as stretch-activation. X-ray diffraction is clearly an enormously powerful tool in studies of muscle. It has already provided a wealth of detail on muscle ultrastructure; it is providing ever more fascinating insights into molecular events in the 50-year old sliding filament mechanism, and there remains a great deal more potential that is as yet untapped.

  18. New HMI hard X-ray Diffraction Beamlines at BESSY

    SciTech Connect

    Denks, I. A.; Genzel, C.; Dudzik, E.; Feyerherm, R.; Klaus, M.; Wagener, G.

    2007-01-19

    Since April 2005 the Hahn-Meitner-Institute is operating two new beamlines for energy dispersive diffraction experiments (EDDI) and for (resonant) magnetic scattering (MAGS) at BESSY. The source for both beamlines is a superconducting 7 T multipole wiggler which provides hard X-ray photons with energies between 4 and 150 keV. The EDDI beamline uses the white beam and is intended for residual stress measurements on small samples as well as heavy engineering parts. The MAGS beamline delivers a focussed monochromatic beam with photon fluxes in the 1012 (s 100 mA 0.1 % bandwidth)-1 range at energies from 4 to 30 keV. It is equipped for single crystal diffraction and resonant (magnetic) scattering experiments as well as for the study of thin films, micro-, and nanostructures in materials science.

  19. New HMI hard X-ray Diffraction Beamlines at BESSY

    NASA Astrophysics Data System (ADS)

    Denks, I. A.; Genzel, C.; Dudzik, E.; Feyerherm, R.; Klaus, M.; Wagener, G.

    2007-01-01

    Since April 2005 the Hahn-Meitner-Institute is operating two new beamlines for energy dispersive diffraction experiments (EDDI) and for (resonant) magnetic scattering (MAGS) at BESSY. The source for both beamlines is a superconducting 7 T multipole wiggler which provides hard X-ray photons with energies between 4 and 150 keV. The EDDI beamline uses the white beam and is intended for residual stress measurements on small samples as well as heavy engineering parts. The MAGS beamline delivers a focussed monochromatic beam with photon fluxes in the 1012 (s 100 mA 0.1 % bandwidth)-1 range at energies from 4 to 30 keV. It is equipped for single crystal diffraction and resonant (magnetic) scattering experiments as well as for the study of thin films, micro-, and nanostructures in materials science.

  20. An image focusing means by using an opaque object to diffract x-rays

    DOEpatents

    Sommargren, Gary E.; Weaver, H. Joseph

    1991-01-01

    The invention provides a method and apparatus for focusing and imaging x-rays. An opaque sphere is used as a diffractive imaging element to diffract x-rays from an object so that the divergent x-ray wavefronts are transformed into convergent wavefronts and are brought to focus to form an image of the object with a large depth of field.

  1. Characterization of X-Ray Diffraction System with a Microfocus X-Ray Source and a Polycapillary Optic

    NASA Technical Reports Server (NTRS)

    Gubarev, Mikhail; Marshall, Joy K.; Ciszak, Ewa; Ponomarev, Igor

    2000-01-01

    We present here an optimized microfocus x-ray source and polycapillary optic system designed for diffraction of small protein crystals. The x-ray beam is formed by a 5.5mm focal length capillary collimator coupled with a 40 micron x-ray source operating at 46Watts. Measurements of the x-ray flux, the divergence and the spectral characteristics of the beam are presented, This optimized system provides a seven fold greater flux than our recently reported configuration [M. Gubarev, et al., J. of Applied Crystallography (2000) 33, in press]. We now make a comparison with a 5kWatts rotating anode generator (Rigaku) coupled with confocal multilayer focusing mirrors (Osmic, CMF12- 38Cu6). The microfocus x-ray source and polycapillary collimator system delivers 60% of the x-ray flux from the rotating anode system. Additional ways to improve our microfocus x-ray system, and thus increase the x-ray flux will be discussed.

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

    PubMed

    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

    2016-09-01

    Owing to its extreme sensitivity, quantitative mapping of elemental distributions via X-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. PMID:27577770

  3. X-ray diffraction characterization of thin superconductive films

    SciTech Connect

    Kozaczek, K.J.; Watkins, T.R.; Book, G.W.; Carter, W.B.

    1995-12-31

    The physical and mechanical properties of thin films are often different from the properties of bulk material and are dictated by the film/substrate orientation relationship, crystal anisotropy and crystalgraphic texture of the film. X-ray diffraction texture analysis provides information about preferential film growth and can be used for optimization of deposition parameters and prediction of properties of thin films. An x-ray back reflection technique using the Braga-Brentano geometry with experimental corrections for absorption and defocusing was used to study thin ceramic films deposited by combustion chemical vapor deposition (CCVD). The film/substrate orientation relationships of YBa{sub 2}Cu{sub 3}O{sub x} (YBCO) superconducting thin films deposited via CCVD on single crystal MgO and polycrystalline silver substrates were studied. The as-deposited films on single crystal (100) MgO substrates showed strong preferential growth with the basal plane parallel to the substrate surface (c-axis up growth). Texture analysis showed two in-plane alignment orientations of the film with respect to the substrate, with YBCO [100] and [110] aligned with the [100] MgO substrate. YBCO films deposited on cold-rolled polycrystalline silver displayed c-axis up growth indicating that the orientation of the polycrystalline substrate (brass type texture) did not induce detectable in-plane preferential growth of the YBCO.

  4. The first X-ray diffraction measurements on Mars.

    PubMed

    Bish, David; Blake, David; Vaniman, David; Sarrazin, Philippe; Bristow, Thomas; Achilles, Cherie; Dera, Przemyslaw; Chipera, Steve; Crisp, Joy; Downs, R T; Farmer, Jack; Gailhanou, Marc; Ming, Doug; Morookian, John Michael; Morris, Richard; Morrison, Shaunna; Rampe, Elizabeth; Treiman, Allan; Yen, Albert

    2014-11-01

    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. PMID:25485131

  5. (Diffraction gratings used in x-ray spectroscopy): Final report

    SciTech Connect

    Smith, H.I.

    1988-11-01

    This subcontract was initiated in order to facilitate the development at MIT of technologies for fabricating the very fine diffraction grating required in x-ray spectroscopy at Lawrence Livermore Laboratory (LLL). These gratings are generally gold transmission gratings with spatial periods of 200 nm or less. The major focus of our efforts was to develop a means of fabricating gratings of 100 nm period. We explored two approaches: e-beam fabrication of x-ray lithography masks, and achromatic holographic lithography. This work was pursued by Erik Anderson as a major component of his Ph.D. thesis. Erik was successful in both the e-beam and holographic approaches. However, the e-beam method proved to be highly impractical: exposure times of about 115 days would be required to cover an area of 1 cm/sup 2/. The achromatic holography, on the other hand, should be capable of exposing areas well in excess of 1 cm/sup 2/ in times under 1 hour. Moreover, 100 nm-period gratings produced by achromatic holography are coherent over their entire area whereas gratings produced by e-beam lithography are coherent only over areas /approximately/100 ..mu..m. The remainder of this report consists of portions excerpted from Erik Anderson's thesis. These contain all the details of our work on 100 nm period gratings. 26 refs., 17 figs.

  6. The first X-ray diffraction measurements on Mars

    PubMed Central

    Bish, David; Blake, David; Vaniman, David; Sarrazin, Philippe; Bristow, Thomas; Achilles, Cherie; Dera, Przemyslaw; Chipera, Steve; Crisp, Joy; Downs, R. T.; Farmer, Jack; Gailhanou, Marc; Ming, Doug; Morookian, John Michael; Morris, Richard; Morrison, Shaunna; Rampe, Elizabeth; Treiman, Allan; Yen, Albert

    2014-01-01

    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. PMID:25485131

  7. Biological imaging by soft X-ray diffraction microscopy

    NASA Astrophysics Data System (ADS)

    Shapiro, David

    We have developed a microscope for soft x-ray diffraction imaging of dry or frozen hydrated biological specimens. This lensless imaging system does not suffer from the resolution or specimen thickness limitations that other short wavelength microscopes experience. The microscope, currently situated at beamline 9.0.1 of the Advanced Light Source, can collect diffraction data to 12 nm resolution with 750 eV photons and 17 nm resolution with 520 eV photons. The specimen can be rotated with a precision goniometer through an angle of 160 degrees allowing for the collection of nearly complete three-dimensional diffraction data. The microscope is fully computer controlled through a graphical user interface and a scripting language automates the collection of both two-dimensional and three-dimensional data. Diffraction data from a freeze-dried dwarf yeast cell, Saccharomyces cerevisiae carrying the CLN3-1 mutation, was collected to 12 run resolution from 8 specimen orientations spanning a total rotation of 8 degrees. The diffraction data was phased using the difference map algorithm and the reconstructions provide real space images of the cell to 30 nm resolution from each of the orientations. The agreement of the different reconstructions provides confidence in the recovered, and previously unknown, structure and indicates the three dimensionality of the cell. This work represents the first imaging of the natural complex refractive contrast from a whole unstained cell by the diffraction microscopy method and has achieved a resolution superior to lens based x-ray tomographic reconstructions of similar specimens. Studies of the effects of exposure to large radiation doses were also carried out. It was determined that the freeze-dried cell suffers from an initial collapse, which is followed by a uniform, but slow, shrinkage. This structural damage to the cell is not accompanied by a diminished ability to see small features in the specimen. Preliminary measurements on frozen

  8. X-Ray Diffraction and Imaging Study of Imperfections of Crystallized Lysozyme with Coherent X-Rays

    NASA Technical Reports Server (NTRS)

    Hu, Zheng-Wei; Chu, Y. S.; Lai, B.; Cai, Z.; Thomas, B. R.; Chernov, A. A.

    2003-01-01

    Phase-sensitive x-ray diffraction imaging and high angular-resolution diffraction combined with phase contrast radiographic imaging are employed to characterize defects and perfection of a uniformly grown tetragonal lysozyme crystal in symmetric Laue case. The fill width at half-maximum (FWHM) of a 4 4 0 rocking curve measured from the original crystal is approximately 16.7 arcseconds, and defects, which include point defects, line defects, and microscopic domains, have been clearly observed in the diffraction images of the crystal. The observed line defects carry distinct dislocation features running approximately along the <110> growth front, and they have been found to originate mostly at a central growth area and occasionally at outer growth regions. Individual point defects trapped at a crystal nucleus are resolved in the images of high sensitivity to defects. Slow dehydration has led to the broadening of the 4 4 0 rocking curve by a factor of approximately 2.4. A significant change of the defect structure and configuration with drying has been revealed, which suggests the dehydration induced migration and evolution of dislocations and lattice rearrangements to reduce overall strain energy. The sufficient details of the observed defects shed light upon perfection, nucleation and growth, and properties of protein crystals.

  9. Point diffraction interferometry at soft x-ray wavelengths

    SciTech Connect

    Sommargren, G.E.; Hostetler, R.

    1993-07-01

    To achieve the image performance necessary for soft x-ray projection lithography, interferometric testing at the design wavelength is required to accurately characterize the wavefront of the imaging system. The wavefront depends not only on the surface figure of the individual optics and on their relative alignment, but also on aperture dependent phase shifts induced by the resonant multilayer coatings on the optical surfaces. This paper describes the design and lithographic fabrication of an array of point diffraction interferometers on a silicon nitride membrane that has been over-coated with a spatially graded partially transmitting film to provide fringe contrast control. Experimental results using a visible light analogue (larger pinholes and different transmission gradient) will be shown.

  10. Powder X-ray diffraction laboratory, Reston, Virginia

    USGS Publications Warehouse

    Piatak, Nadine M.; Dulong, Frank T.; Jackson, John C.; Folger, Helen W.

    2014-01-01

    The powder x-ray diffraction (XRD) laboratory is managed jointly by the Eastern Mineral and Environmental Resources and Eastern Energy Resources Science Centers. Laboratory scientists collaborate on a wide variety of research problems involving other U.S. Geological Survey (USGS) science centers and government agencies, universities, and industry. Capabilities include identification and quantification of crystalline and amorphous phases, and crystallographic and atomic structure analysis for a wide variety of sample media. Customized laboratory procedures and analyses commonly are used to characterize non-routine samples including, but not limited to, organic and inorganic components in petroleum source rocks, ore and mine waste, clay minerals, and glassy phases. Procedures can be adapted to meet a variety of research objectives.

  11. X-ray diffraction of actively shortening muscle.

    PubMed

    Podolsky, R J; St Onge, H; Yu, L; Lymn, R W

    1976-03-01

    Low angle x-ray diffraction patterns were obtained from resting and activated frog sartorius muscles by means of a position-sensitive detector. Although the intensity ratio I10/I11 decreased many-fold upon activation, it was nearly the same during isometric and isotonic contraction. Thus, motion has a much smaller effect on the low order equatorial pattern than the transition from rest to activity. Analysis of the 10 and 11 reflections separately showed that I10 and I11 change reciprocally upon activation, and that they both increase by a small amount in the transition from isometric to isotonic contraction. If the intensity ratio can be taken as a measure of cross-bridge number, the results provide evidence that the drop in force in an actively shortening muscle is due primarily to the influence of motion on the configuration, rather than the number, of cross-bridges. PMID:1062793

  12. Special properties of X-ray diffraction on carbon onions

    SciTech Connect

    Yastrebov, S. G. Ivanov-Omskii, V. I.

    2007-12-15

    The kinematic theory of X-ray diffraction was applied to the study of the most intense Bragg's reflection observed for carbon onions. It was shown that the agreement with experimental data was attained using a convolution of a Lorentzian contour with regard to the distribution of onion sizes and of an asymmetric contour taking into account the fluctuations of intershell distances inside the particle. It can be assumed that the observed scatter in intershell distances indicates a nonequilibrium state of the internal configuration of onion shells. It appeared to be possible to estimate not only the average onion size, which exceeds the average size of pristine nanodiamonds that are used for onion preparation by annealing, but their size distribution function as well.

  13. Preparation and X-ray diffraction studies of curium hydrides

    NASA Astrophysics Data System (ADS)

    Gibson, J. K.; Haire, R. G.

    1985-10-01

    Curium hydrides were prepared by reaction of curium-248 metal with hydrogen and characterized by X-ray powder diffraction. Several of the syntheses resulted in a hexagonal compound with average lattice parameters of a0 = 0.3769(8) nm and c0 = 0.6732(12) nm. These products are considered to be CmH 3-δ by analogy with the behavior of lanthanide-hydrogen and lighter actinide-hydrogen systems. Face-centered cubic products with an average lattice parameter of a0 = 0.5322(4) nm were obtained from other curium hydride preparations. This parameter is slightly smaller than that reported previously for cubic curium dihydride, CmH 2+ x (B. M. Bansal and D. Damien, Inorg. Nucl. Chem. Lett., 6, 603, 1970). The present results established a continuation of typical heavy trivalent lanthanide-like behavior of the transuranium actinide-hydrogen systems through curium.

  14. X-ray diffraction diagnostic design for the National Ignition Facility

    NASA Astrophysics Data System (ADS)

    Ahmed, Maryum F.; House, Allen; Smith, R. F.; Ayers, Jay; Lamb, Zachary S.; Swift, David W.

    2013-09-01

    This paper describes the design considerations for Target Diffraction In-Situ (TARDIS), an x-ray diffraction diagnostic at the National Ignition Facility. A crystal sample is ramp-compressed to peak pressures between 10 and 30 Mbar and, during a pressure hold period, is probed with quasi-monochromatic x-rays emanating from a backlighter source foil. The crystal spectrography diffraction lines are recorded onto image plates. The crystal sample, filter, and image plates are packaged into one assembly, allowing for accurate and repeatable target to image plate registration. Unconverted laser light impinges upon the device, generating debris, the effects of which have been mitigated. Dimpled blast shields, high strength steel alloy, and high-z tungsten are used to shield and protect the image plates. A tapered opening was designed to provide adequate thickness of shielding materials without blocking the drive beams or x-ray source from reaching the crystal target. The high strength steel unit serves as a mount for the crystal target and x-ray source foil. A tungsten body contains the imaging components. Inside this sub-assembly, there are three image plates: a 160 degree field of view curved plate directly opposite the target opening and two flat plates for the top and bottom. A polycarbonate frame, coated with the appropriate filter material and embedded with registration features for image plate location, is inserted into the diagnostic body. The target assembly is metrologized and then the diagnostic assembly is attached.

  15. A new theory for X-ray diffraction

    SciTech Connect

    Fewster, Paul F.

    2014-05-01

    By considering the scattering distributed throughout space, there is an intensity enhancement at the Bragg angle even when the Bragg condition is not satisfied. This leads to an alternative explanation for the diffraction from powders and small crystals. This article proposes a new theory of X-ray scattering that has particular relevance to powder diffraction. The underlying concept of this theory is that the scattering from a crystal or crystallite is distributed throughout space: this leads to the effect that enhanced scatter can be observed at the ‘Bragg position’ even if the ‘Bragg condition’ is not satisfied. The scatter from a single crystal or crystallite, in any fixed orientation, has the fascinating property of contributing simultaneously to many ‘Bragg positions’. It also explains why diffraction peaks are obtained from samples with very few crystallites, which cannot be explained with the conventional theory. The intensity ratios for an Si powder sample are predicted with greater accuracy and the temperature factors are more realistic. Another consequence is that this new theory predicts a reliability in the intensity measurements which agrees much more closely with experimental observations compared to conventional theory that is based on ‘Bragg-type’ scatter. The role of dynamical effects (extinction etc.) is discussed and how they are suppressed with diffuse scattering. An alternative explanation for the Lorentz factor is presented that is more general and based on the capture volume in diffraction space. This theory, when applied to the scattering from powders, will evaluate the full scattering profile, including peak widths and the ‘background’. The theory should provide an increased understanding of the reliability of powder diffraction measurements, and may also have wider implications for the analysis of powder diffraction data, by increasing the accuracy of intensities predicted from structural models.

  16. Phosphor Scanner For Imaging X-Ray Diffraction

    NASA Technical Reports Server (NTRS)

    Carter, Daniel C.; Hecht, Diana L.; Witherow, William K.

    1992-01-01

    Improved optoelectronic scanning apparatus generates digitized image of x-ray image recorded in phosphor. Scanning fiber-optic probe supplies laser light stimulating luminescence in areas of phosphor exposed to x rays. Luminescence passes through probe and fiber to integrating sphere and photomultiplier. Sensitivity and resolution exceed previously available scanners. Intended for use in x-ray crystallography, medical radiography, and molecular biology.

  17. Development of Coherent X-ray Diffraction Apparatus with Kirkpatrick-Baez Mirror Optics

    SciTech Connect

    Takahashi, Y.; Tsutsumi, R.; Mimura, H.; Matsuyama, S.; Nishino, Y.; Ishikawa, T.; Yamauchi, K.

    2011-09-09

    To realize coherent x-ray diffraction microscopy with higher spatial resolution, it is necessary to increase the density of x-ray photons illuminated onto the sample. In this study, we developed a coherent x-ray diffraction apparatus with Kirkpatrick-Baez mirror optics. By using mirrors fabricated by elastic emission machining, a high-density coherent x-ray beam was produced. In a demonstration experiment using a silver nanocube as a sample, a high-contrast coherent x-ray diffraction pattern was observed over a wide-q range. This proves that both the density and the degree of coherence of the focused beam were high.

  18. X-ray Diffraction Spectra in Cu-Implanted SiO{sub 2} Films on Si(100) Substrates

    SciTech Connect

    Shirokoff, J.; Lewis, J. Courtenay

    2010-10-29

    Cu-implanted SiO{sub 2} films on Si(100) have been studied using x-ray methods and x-ray diffraction pattern processing. The x-ray results indicate the presence of a preferred orientation for Cu {l_brace}111{r_brace} planes parallel to the substrate surface without directional orientation for Cu-implanted SiO{sub 2}/Si(100) and nano-crystalline-Cu/SiO{sub 2}/Si(100)(ie. after implanted and annealed Cu). The x-ray diffraction spectra of the Cu-implanted and nano-crystalline-Cu phases were analyzed (ie. in terms of peak search, profile fit, crystallite size) and compared to data from complimentary techniques (RBS, TEM). Results are discussed with respect to x-ray spectral lines shapes derived from XRD spectra processing and the nanostructure problem.

  19. Nanostructured diffractive optical devices for soft X-ray microscopes

    NASA Astrophysics Data System (ADS)

    Hambach, D.; Peuker, M.; Schneider, G.

    2001-07-01

    The new transmission X-ray microscope (TXM) installed at the BESSY II electron storage ring uses an off-axis transmission zone plate (OTZ) as diffractive and focusing element of the condenser-monochromator setup. A high resolution micro-zone plate (MZP) forms a magnified image on a CCD-detector. Both, the OTZ with an active area of up to 24 mm2 and the MZP with zone widths as small as 25 nm are generated by a process including electron beam lithography (EBL), dry etching and subsequent electroplating of nickel on top of silicon membrane substrates with about 100- 150 nm thickness. The combination of a larger zone width and the usage of nickel zone structures allows to increase the diffraction efficiency of the condenser element at least by a factor of 3 compared to the earlier used KZP7 condenser zone plate in the TXM at BESSY I. Groove diffraction efficiencies of 21.6% and 14.7% were measured for MZP objectives with 40 and 25 nm outermost zone width, respectively.

  20. Diffracted X-ray tracking for monitoring intramolecular motion in individual protein molecules using broad band X-ray

    SciTech Connect

    Ichiyanagi, Kouhei; Sasaki, Yuji C.; Sekiguchi, Hiroshi; Hoshino, Masato; Kajiwara, Kentaro; Senba, Yasunori; Ohashi, Haruhiko; Ohta, Noboru; Hoshisashi, Kentaro; Jae-won, Chang; Tokue, Maki; Matsushita, Yufuku; Nishijima, Masaki; Inoue, Yoshihisa; Yagi, Naoto

    2013-10-15

    Diffracted X-ray tracking (DXT) enables the tilting and twisting motions of single protein molecules to be monitored with micro- to milliradian resolution using a highly brilliant X-ray source with a wide energy bandwidth. We have developed a technique to monitor single molecules using gold nanocrystals attached to individual protein molecules using the BL28B2 beamline at SPring-8. In this paper we present the installation of a single toroidal X-ray mirror at BL28B2 to focus X-rays in an energy range of 10–20 keV (△E/E = 82% for an X-ray with a wide energy bandwidth). With this beamline we tracked diffraction spots from gold nanocrystals over a wide angle range than that using quasi-monochromatic X-rays. Application of the wide angle DXT technique to biological systems enabled us to observe the on-site motions of single protein molecules that have been functionalized in vivo. We further extend the capability of DXT by observing the fractional tilting and twisting motions of inner proteins under various conditions. As a proof of this methodology and to determine instrumental performance the intramolecular motions of a human serum albumin complex with 2-anthracenecarboxylic acid was investigated using the BL28B2 beamline. The random tilting and twisting intramolecular motions are shown to be directly linked to the movement of individual protein molecules in the buffer solution.

  1. Elimination of higher-order diffraction using zigzag transmission grating in soft x-ray region

    SciTech Connect

    Zang, H. P.; Wang, C. K.; Gao, Y. L.; Zhou, W. M.; Kuang, L. Y.; Wei, L.; Fan, W.; Zhang, W. H.; Zhao, Z. Q.; Cao, L. F.; Gu, Y. Q.; Zhang, B. H.; Jiang, G.; Zhu, X. L.; Xie, C. Q.; Zhao, Y. D.; Cui, M. Q.

    2012-03-12

    We present a realization of the sinusoidal transmission function using a series of zigzag-profiled strips where the transmission takes on the binary values 0 and 1 in a two-dimensional distribution. A zigzag transmission grating of 1000 line/mm has been fabricated and demonstrated on the soft x-ray beam of synchrotron radiation. The axial single-order diffraction indicates that the zigzag transmission grating is adequate for spectroscopic application.

  2. Elimination of higher-order diffraction using zigzag transmission grating in soft x-ray region

    NASA Astrophysics Data System (ADS)

    Zang, H. P.; Wang, C. K.; Gao, Y. L.; Zhou, W. M.; Kuang, L. Y.; Wei, L.; Fan, W.; Zhang, W. H.; Zhao, Z. Q.; Cao, L. F.; Gu, Y. Q.; Zhang, B. H.; Jiang, G.; Zhu, X. L.; Xie, C. Q.; Zhao, Y. D.; Cui, M. Q.

    2012-03-01

    We present a realization of the sinusoidal transmission function using a series of zigzag-profiled strips where the transmission takes on the binary values 0 and 1 in a two-dimensional distribution. A zigzag transmission grating of 1000 line/mm has been fabricated and demonstrated on the soft x-ray beam of synchrotron radiation. The axial single-order diffraction indicates that the zigzag transmission grating is adequate for spectroscopic application.

  3. Hard X-ray nanoimaging method using local diffraction from metal wire

    SciTech Connect

    Takano, Hidekazu Konishi, Shigeki; Shimomura, Sho; Azuma, Hiroaki; Tsusaka, Yoshiyuki; Kagoshima, Yasushi

    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.

  4. D-25 OBSERVATIONS OF SHOCKED METALLIC SURFACES WITH SINGLE-PULSE X-RAY DIFFRACTION

    SciTech Connect

    Morgan, D. V.; Grover, M.; Macy, D.; Madlener, M.; Stevens, G.; Turley, W. D.; Veeser, L.

    2009-01-01

    A single-pulse x-ray diffraction (XRD) diagnostic has been developed for the investigation of shocked material properties on a very short time scale. The diagnostic, which consists of a 37-stage Marx bank high-voltage pulse generator coupled to a needle-and-washer electron beam diode via coaxial cable, produces line and bremsstrahlung x-ray emission in a 40-ns pulse. A selected anode of either silver or molybdenum produces characteristic K lines used for diffraction. The x-ray beam passes through a pinhole collimator and is incident on the sample with an approximately 2-mm by 5-mm spot and 1° full-width-half-maximum angular divergence. Coherent scattering from the sample produces a Debye-Scherrer diffraction pattern on an image plate 75 mm from the polycrystalline sample surface. An experimental study of the polycrystalline structures of zirconium and tin under high-pressure shock loading has been conducted with single-pulse XRD. The experimental targets were 0.1-mm-thick foils of zirconium and tin using 0.4-mm-thick vitreous carbon back windows for shock-loading, and the shocks were produced by either Detasheet or PBX-9501 high explosives buffered by 1-mm-thick 6061-T6 aluminum. The diffraction patterns from both shocked zirconium and tin indicated a phase transition into a polymorphic mix of amorphous and new solid phases.

  5. A new theory for X-ray diffraction

    PubMed Central

    Fewster, Paul F.

    2014-01-01

    This article proposes a new theory of X-ray scattering that has particular relevance to powder diffraction. The underlying concept of this theory is that the scattering from a crystal or crystallite is distributed throughout space: this leads to the effect that enhanced scatter can be observed at the ‘Bragg position’ even if the ‘Bragg condition’ is not satisfied. The scatter from a single crystal or crystallite, in any fixed orientation, has the fascinating property of contributing simultaneously to many ‘Bragg positions’. It also explains why diffraction peaks are obtained from samples with very few crystallites, which cannot be explained with the conventional theory. The intensity ratios for an Si powder sample are predicted with greater accuracy and the temperature factors are more realistic. Another consequence is that this new theory predicts a reliability in the intensity measurements which agrees much more closely with experimental observations compared to conventional theory that is based on ‘Bragg-type’ scatter. The role of dynamical effects (extinction etc.) is discussed and how they are suppressed with diffuse scattering. An alternative explanation for the Lorentz factor is presented that is more general and based on the capture volume in diffraction space. This theory, when applied to the scattering from powders, will evaluate the full scattering profile, including peak widths and the ‘background’. The theory should provide an increased understanding of the reliability of powder diffraction measurements, and may also have wider implications for the analysis of powder diffraction data, by increasing the accuracy of intensities predicted from structural models. PMID:24815975

  6. X-ray Weak Broad-line Qquasars: Absorption or Intrinsic X-ray Weakness

    NASA Technical Reports Server (NTRS)

    Mushotzky, Richard (Technical Monitor); Risaliti, Guida

    2005-01-01

    XMM observations of X-ray weak quasars have been performed during 2003 and 2004. The data for all the observations have become available in 2004 (there has been a delay of several months on the initial schedule, due to high background flares which contaminated the observations: as a consequence, most of them had to be rescheduled). We have reduced and analyzed all the data, and obtained interesting scientific results. Out of the eight sources, 4 are confirmed to be extremely X-ray weak, in agreement with the results of previous Chandra observations. 3 sources are confined to be highly variable both in flux (by factor 20-50) and in spectral properties (dramatic changes in spectral index). For both these groups of objects we are completing a publication: 1) For the X-ray weak sources, a paper is submitted with a complete analysis of the X-ray spectra both from Chandra and XMM-Newton, and a comparison with optical and near-IR photometry obtained from all-sky surveys. Possible models for the unusual spectral energy distribution of these sources are also presented. 2) For the variable sources, a paper is being finalized where the X-ray spectra obtained with XMM-Newton are compared with previous X-ray observations and with observations at other wavelengths. It is shown that these sources are high luminosity and extreme cases of the highly variable class of narrow-line Seyfert Is. In order to further understand the nature of these X-ray weak quasars, we submitted proposals for spectroscopy at optical and infrared telescopes. We obtained time at the TNG 4 meter telescope for near-IR observations and at the Hobby-Eberly Telescope for optical high-resolution spectroscopy. These observations have been performed in early 2004. They will complement the XMM data and will lead to understanding of whether the X-ray weakness of these sources is an intrinsic property or is due to absorption by circum-nuclear material. The infrared spectra of the variable sources have been already

  7. Eta Carinae: X-ray Line Variations during the 2003 X-ray Minimum, and the Orbit Orientation

    NASA Technical Reports Server (NTRS)

    Corcoran, M. F.; Henley, D.; Hamaguchi, K.; Khibashi, K.; Pittard, J. M.; Stevens, I. R.; Gull, T. R.

    2007-01-01

    The future evolution of Eta Carinae will be as a supernova (or hypernova) and black hole. The evolution is highly contingent on mass and angular momentum changes and instabilities. The presence of a companion can serve to trigger instabilities and provide pathways for mass and angular momentum exchange loss. X-rays can be used a a key diagnostic tool: x-ray temperatures trace pre-shock wind velocities, periodic x-ray variability traces the orbit, and x-ray line variations traces the flow and orientation of shocked gas. This brief presentation highlights x-ray line variations from the HETG and presents a model of the colliding wind flow.

  8. Quantitative biological imaging by ptychographic x-ray diffraction microscopy

    PubMed Central

    Giewekemeyer, Klaus; Thibault, Pierre; Kalbfleisch, Sebastian; Beerlink, André; Kewish, Cameron M.; Dierolf, Martin; Pfeiffer, Franz; Salditt, Tim

    2010-01-01

    Recent advances in coherent x-ray diffractive imaging have paved the way to reliable and quantitative imaging of noncompact specimens at the nanometer scale. Introduced a year ago, an advanced implementation of ptychographic coherent diffractive imaging has removed much of the previous limitations regarding sample preparation and illumination conditions. Here, we apply this recent approach toward structure determination at the nanoscale to biological microscopy. We show that the projected electron density of unstained and unsliced freeze-dried cells of the bacterium Deinococcus radiodurans can be derived from the reconstructed phase in a straightforward and reproducible way, with quantified and small errors. Thus, the approach may contribute in the future to the understanding of the highly disputed nucleoid structure of bacterial cells. In the present study, the estimated resolution for the cells was 85 nm (half-period length), whereas 50-nm resolution was demonstrated for lithographic test structures. With respect to the diameter of the pinhole used to illuminate the samples, a superresolution of about 15 was achieved for the cells and 30 for the test structures, respectively. These values should be assessed in view of the low dose applied on the order of ≃1.3·105 Gy, and were shown to scale with photon fluence. PMID:20018650

  9. X-Ray Absorbed, Broad-Lined, Red AGN and the Cosmic X-Ray Background

    NASA Technical Reports Server (NTRS)

    Mushotzky, Richard (Technical Monitor); Wilkes, Belinda

    2005-01-01

    We have obtained XMM spectra for five red, 2MASS AGN, selected from a sample observed by Chandra to be X-ray bright and to cover a range of hardness ratios. Our results confirm the presence of substantial absorbing material in three sources which have optical classifications ranging from Type 1 to Type 2, with an intrinsically flat (hard) power law continuum indicated in the other two. The presence of both X-ray absorption and broad optical emission lines with the usual strength suggests either a small (nuclear) absorber or a favored viewing angle so as to cover the X-ray source but not the broad emission line region (BELR). A soft excess is detected in all three Type 1 sources. We speculate that this soft X-ray emission may arise in an extended region of ionized gas, perhaps linked with the polarized (scattered) light which is a feature of these sources. The spectral complexity revealed by XMM emphasizes the limitations of the low S/N Chandra data. Overall, the new XMM results strengthen our conclusions (Wilkes et al. 2002) that the observed X-ray continua of red AGN are unusually hard at energies greater than 2 keV. Whether due to substantial line-of-sight absorption or to an intrinsically hard or reflection-dominated spectrum, these 'red' AGN have an observed spectral form consistent with contributing significantly to the missing had absorbed population of the Cosmic X-ray Background (CXRB). When absorption and or reflection is taken into account, all these AGN have power law slopes typical of broad-line (Type 1) AGN (Gamma approximately 1.9). This appears to resolve the spectral paradox which for so long has existed between the CXRB and the AGN thought to be the dominant contributors. It also suggests two scenarios whereby Type 1 AGN/QSOs may be responsible for a significant fraction of the CXRB at energies above 2 keV: 1) X-ray absorbed AGN/QSOs with visible broad emission lines; 2) AGN/QSOs with complex spectra whose hardness greater than 2 keV is not

  10. Very High Resolution Solar X-ray Imaging Using Diffractive Optics

    NASA Technical Reports Server (NTRS)

    Dennis, B. R.; Skinner, G. K.; Li, M. J.; Shih, A. Y.

    2012-01-01

    This paper describes the development of X-ray diffractive optics for imaging solar flares with better than 0.1 arcsec angular resolution. X-ray images with this resolution of the greater than or equal to 10 MK plasma in solar active regions and solar flares would allow the cross-sectional area of magnetic loops to be resolved and the coronal flare energy release region itself to be probed. The objective of this work is to obtain X-ray images in the iron-line complex at 6.7 keV observed during solar flares with an angular resolution as fine as 0.1 arcsec - over an order of magnitude finer than is now possible. This line emission is from highly ionized iron atoms, primarily Fe xxv, in the hottest flare plasma at temperatures in excess of approximately equal to 10 MK. It provides information on the flare morphology, the iron abundance, and the distribution of the hot plasma. Studying how this plasma is heated to such high temperatures in such short times during solar flares is of critical importance in understanding these powerful transient events, one of the major objectives of solar physics.We describe the design, fabrication, and testing of phase zone plate X-ray lenses with focal lengths of approximately equal to 100 m at these energies that would be capable of achieving these objectives. We show how such lenses could be included on a two-spacecraft formation-flying mission with the lenses on the spacecraft closest to the Sun and an X-ray imaging array on the second spacecraft in the focal plane approximately equal to 100 m away. High resolution X-ray images could be obtained when the two spacecraft are aligned with the region of interest on the Sun. Requirements and constraints for the control of the two spacecraft are discussed together with the overall feasibility of such a formation-flying mission.

  11. Setup for in situ x-ray diffraction study of swift heavy ion irradiated materials

    SciTech Connect

    Kulriya, P. K.; Singh, F.; Tripathi, A.; Ahuja, R.; Kothari, A.; Dutt, R. N.; Mishra, Y. K.; Kumar, Amit; Avasthi, D. K.

    2007-11-15

    An in situ x-ray diffraction (XRD) setup is designed and installed in the materials science beam line of the Pelletron accelerator at the Inter-University Accelerator Centre for in situ studies of phase change in swift heavy ion irradiated materials. A high vacuum chamber with suitable windows for incident and diffracted X-rays is integrated with the goniometer and the beamline. Indigenously made liquid nitrogen (LN{sub 2}) temperature sample cooling unit is installed. The snapshots of growth of particles with fluence of 90 MeV Ni ions were recorded using in situ XRD experiment, illustrating the potential of this in situ facility. A thin film of C{sub 60} was used to test the sample cooling unit. It shows that the phase of the C{sub 60} film transforms from a cubic lattice (at room temperature) to a fcc lattice at around T=255 K.

  12. X-ray Diffraction Study of Molybdenum to 900 GPa

    NASA Astrophysics Data System (ADS)

    Wang, J.; Coppari, F.; Smith, R.; Eggert, J.; Boehly, T.; Collins, G. W.; Duffy, T. S.

    2013-12-01

    Molybdenum (Mo) is a transition metal that is important as a high-pressure standard. Its equation of state, structure, and melting behavior have been explored extensively in both experimental and theoretical studies. Melting data up to the Mbar pressure region from static compression experiments in the diamond anvil cell [Errandonea et al. 2004] are inconsistent with shock wave sound velocity measurements [Hixson et al., 1989]. There are also conflicting reports as to whether body-centered cubic (BCC) Mo transforms to a face-centered cubic (FCC), hexagonal close packed (HCP) or double hexagonal close packed (DHCP) structure at either high pressure or high pressure and temperature conditions [Belonoshko et al. 2008, Mikhaylushkin et al., 2008 and Cazorla et al., 2008]. Recently, a phase transition from BCC to the DHCP phase at 660 GPa and 0 K was predicted using the particle swam optimization (PSO) method (Wang et al, 2013). Here we report an x-ray diffraction study of dynamically compressed molybdenum. Experiments were conducted using the Omega laser at the Laboratory for Laser Energetics at the University of Rochester. Mo targets were either ramp or shock compressed using a laser drive. In ramp loading, the sample is compressed sufficiently slowly that a shock wave does not form. This results in lower temperatures, keeping the sample in the solid state to higher pressures. X-ray diffraction measurements were performed using quasi-monochromatic x-rays from a highly ionized He-α Cu source and image plate detectors. Upon ramp compression, we found no evidence of phase transition in solid Mo up to 900 GPa. The observed peaks can be assigned to the (110) and (200) or (220) reflections of BCC Mo up to the highest pressure, indicating that Mo does not melt under ramp loading to maximum pressure reached. Under shock loading, we did not observe any evidence for the solid-solid phase transformation around 210 GPa as reported in previous work (Hixson et al, 1989). The BCC

  13. Measuring the x-ray resolving power of bent potassium acid phthalate diffraction crystalsa)

    NASA Astrophysics Data System (ADS)

    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.

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

    SciTech Connect

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

    2014-11-15

    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.

  15. Measuring the X-ray Resolving Power of Bent Potassium Acid Phthalate Diffraction Crystals

    SciTech Connect

    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 (SNL) in Albuquerque, NM. 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 dual goniometer 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.

  16. Flash X-Ray Diffraction System for Fast, Single-PulseTemperature and Phase Transition Measurements (Pre-print)

    SciTech Connect

    Michael J. Madlener; Dane V. Morgan

    2007-06-12

    A new, fast, single-pulse diagnostic for determining phase transitions and measuring the bulk temperature of polycrystalline metal objects has been developed. The diagnostic consists of a 37-stage Marx bank with a cable-coupled X-ray diode that produces a 35-ns pulse of mostly 0.71-{angstrom} monochromatic X rays and a P-43 fluor coupled to a cooled, charge-coupled device camera by a coherent fiber-optic bundle for detection of scattered X rays. The X-ray beam is collimated to a 1{sup o} divergence in the scattering plane with the combination of a 1.5-mm tungsten pinhole and a 1.5-mm-diameter molybdenum anode. X rays are produced by a high-energy electron beam transiting inward from the cathode to the anode in a needle-and-washer configuration. The anode's characteristic K-{alpha} X-ray emission lines are utilized for this diffraction system. The X-ray anode is heavily shielded in all directions other than the collimated beam. The X-ray diode has a sealed reentrant system, allowing X rays to be produced inside a vacuum containment vessel, close to the sample under study.

  17. Atomic calculations for the Fe XX X-ray lines

    NASA Technical Reports Server (NTRS)

    Mason, H. E.; Bhatia, A. K.

    1983-01-01

    The atomic data presented here and in Bhatia and Mason (1980) allow the calculation of theoretical intensity ratios for all the EUV, UV, and X-ray lines from Fe XX. Tabulations are presently given for the transitions between levels in the 2s2 2p3, 2s2 2p2 3s, and 2s2 2p2 3d configurations of Fe(19+), and electron collision strengths are calculated by means of the 'distorted wave' approximation. In addition to the theoretical X-ray line intensity ratios, new spectral line identifications from a solar flare are presented.

  18. Lattice Misfit Measurement in Inconel 625 BY X-Ray Diffraction Technique

    NASA Astrophysics Data System (ADS)

    Sarkar, A.; Mukherjee, P.; Barat, P.; Jayakumar, T.; Mahadevan, S.; Rai, Sanjay K.

    Determination of lattice misfit and microstructural parameters of the coherent precipitates in Ni based alloy Inconel-625 is a challenging problem as the diffraction peaks of the precipitate and the matrix are completely overlapping. X-ray Diffraction Line Profile Analysis (XRDLPA) has been used to characterize the bulk samples of Inconel 625 at different heat-treated conditions to determine the lattice parameters of the parent phase and also the coherent precipitates by the separation of the overlapping peaks. The lattice misfits of the coherent precipitates with the matrix and their microstructural parameters like size and strain have also been determined.

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

    NASA Astrophysics Data System (ADS)

    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.

  20. Federated repositories of X-ray diffraction images.

    PubMed

    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. PMID:18566516

  1. X-ray diffraction study of crystalline barium titanate ceramics

    SciTech Connect

    Zali, Nurazila Mat; Mahmood, Che Seman; Mohamad, Siti Mariam; Foo, Choo Thye; Murshidi, Julie Adrianny

    2014-02-12

    In this study, BaTiO{sub 3} ceramics have been prepared via solid-state reaction method. The powders were calcined for 2 hours at different temperatures ranging from 600°C to 1200°C. Using X-ray diffraction with a Rietveld analysis, the phase formation and crystal structure of the BaTiO{sub 3} powders were studied. Change in crystallite size and tetragonality as a function of calcination temperature were also discussed. It has been found that the formation of pure perovskite phase of BaTiO{sub 3} began at calcination condition of 1000 °C for 2 hours. The crystal structure of BaTiO{sub 3} formed is in the tetragonal structure. The second phases of BaCO{sub 3} and TiO{sub 2} existed with calcination temperature below 1000 °C. Purity, crystallite size and tetragonality of BaTiO{sub 3} powders were found to increase with increasing calcination temperature.

  2. Soft X-Ray Diffraction Microscopy of a Frozen Hydrated Yeast Cell

    PubMed Central

    Huang, Xiaojing; Nelson, Johanna; Kirz, Janos; Lima, Enju; Marchesini, Stefano; Miao, Huijie; Neiman, Aaron M.; Shapiro, David; Steinbrener, Jan; Stewart, Andrew; Turner, Joshua J.; Jacobsen, Chris

    2010-01-01

    We report the first image of an intact, frozen hydrated eukaryotic cell using x-ray diffraction microscopy, or coherent x-ray diffraction imaging. By plunge freezing the specimen in liquid ethane and maintaining it below −170 °C, artifacts due to dehydration, ice crystallization, and radiation damage are greatly reduced. In this example, coherent diffraction data using 520 eV x rays were recorded and reconstructed to reveal a budding yeast cell at a resolution better than 25 nm. This demonstration represents an important step towards high resolution imaging of cells in their natural, hydrated state, without limitations imposed by x-ray optics. PMID:20365955

  3. Soft X-Ray Diffraction Microscopy of a Frozen Hydrated Yeast Cell

    DOE PAGESBeta

    Huang, Xiaojing; Nelson, Johanna; Kirz, Janos; Lima, Enju; Marchesini, Stefano; Miao, Huijie; Neiman, Aaron M.; Shapiro, David; Steinbrener, Jan; Stewart, Andrew; et al

    2009-11-01

    We report the first image of an intact, frozen hydrated eukaryotic cell using x-ray diffraction microscopy, or coherent x-ray diffraction imaging. By plunge freezing the specimen in liquid ethane and maintaining it below -170 °C, artifacts due to dehydration, ice crystallization, and radiation damage are greatly reduced. In this example, coherent diffraction data using 520 eV x rays were recorded and reconstructed to reveal a budding yeast cell at a resolution better than 25 nm. This demonstration represents an important step towards high resolution imaging of cells in their natural, hydrated state, without limitations imposed by x-ray optics.

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

    SciTech Connect

    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.

  5. TYPING SUPERNOVA REMNANTS USING X-RAY LINE EMISSION MORPHOLOGIES

    SciTech Connect

    Lopez, L. A.; Ramirez-Ruiz, E.; Badenes, C.; Huppenkothen, D.; Jeltema, T. E.

    2009-11-20

    We present a new observational method to type the explosions of young supernova remnants (SNRs). By measuring the morphology of the Chandra X-ray line emission in 17 Galactic and Large Magellanic Cloud SNRs with a multipole expansion analysis (using power ratios), we find that the core-collapse SNRs are statistically more asymmetric than the Type Ia SNRs. We show that the two classes of supernovae can be separated naturally using this technique because X-ray line morphologies reflect the distinct explosion mechanisms and structure of the circumstellar material. These findings are consistent with recent spectropolarimetry results showing that core-collapse supernovae explosions are intrinsically more asymmetric.

  6. High intensity line source for x-ray spectrometer calibration

    SciTech Connect

    Thoe, R.S.

    1986-06-01

    A high intensity electron-impact x-ray source using a one-dimensional Pierce lens has been built for the purpose of calibrating a bent crystal x-ray spectrometer. This source focuses up to 100 mA of 20-keV electrons to a line on a liquid-cooled anode. The line (which can serve as a virtual slit for the spectrometer) measures approximately 800 ..mu.. x 2 cm. The source is portable and therefore adaptable to numerous types of spectrometer applications. One particular application, the calibration of a high resolution (r = 10/sup 4/) time-resolved cyrstal spectrometer, will be discussed in detail.

  7. Combined synchrotron X-ray tomography and X-ray powder diffraction using a fluorescing metal foil

    SciTech Connect

    Kappen, P.; Arhatari, B. D.; Luu, M. B.; Balaur, E.; Caradoc-Davies, T.

    2013-06-15

    This study realizes the concept of simultaneous micro-X-ray computed tomography and X-ray powder diffraction using a synchrotron beamline. A thin zinc metal foil was placed in the primary, monochromatic synchrotron beam to generate a divergent wave to propagate through the samples of interest onto a CCD detector for tomographic imaging, thus removing the need for large beam illumination and high spatial resolution detection. Both low density materials (kapton tubing and a piece of plant) and higher density materials (Egyptian faience) were investigated, and elemental contrast was explored for the example of Cu and Ni meshes. The viability of parallel powder diffraction using the direct beam transmitted through the foil was demonstrated. The outcomes of this study enable further development of the technique towards in situ tomography/diffraction studies combining micrometer and crystallographic length scales, and towards elemental contrast imaging and reconstruction methods using well defined fluorescence outputs from combinations of known fluorescence targets (elements).

  8. Soft X-ray Excesses and X-ray Line Variability in Cygnus X-3

    NASA Astrophysics Data System (ADS)

    Varlotta, Angelo; McCollough, Michael L

    2014-06-01

    Cygnus X-3 is an X-ray binary (XRB) system containing a stellar-mass compact object, most likely a black hole, and a Wolf-Rayet companion star, which produces collimated, relativistic jets, placing it in the sub-class of XRBs known as microquasars. During a Swift/XRT monitoring program of Cygnus X-3, a soft X-ray excess (below 1 keV) was observed at certain states and phases of activity. This soft excess appears to be similar to the variable soft emission observed in Seyfert galaxies. The presence of these features in Cygnus X-3 would argue for a greater support of the black-hole nature of the compact object and serve to better highlight the similarities of microquasars and AGN. We present the results of our investigations of these soft excesses, as well as the variations of the X-ray Fe line region (6.4-7.0 keV) as a function of the state activity and orbital phase.

  9. A Computer Program for Calculation of Calibration Curves for Quantitative X-Ray Diffraction Analysis.

    ERIC Educational Resources Information Center

    Blanchard, Frank N.

    1980-01-01

    Describes a FORTRAN IV program written to supplement a laboratory exercise dealing with quantitative x-ray diffraction analysis of mixtures of polycrystalline phases in an introductory course in x-ray diffraction. Gives an example of the use of the program and compares calculated and observed calibration data. (Author/GS)

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

    ERIC Educational Resources Information Center

    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…

  11. Strain measurement of pure titanium covered with soft tissue using X-ray diffraction.

    PubMed

    Fujisaki, Kazuhiro; Tadano, Shigeru

    2010-03-01

    Measurement of the stress and strain applied to implants and bone tissue in the human body are important for fracture prediction and evaluations of implant adaptation. The strain of titanium (Ti) materials can be measuring by X-ray diffraction techniques. This study applied X-ray diffraction to the skin tissue-covered Ti. Characteristic X-rays of Mo Kalpha were used and the X-rays diffracted from the Ti were detected through the covering skin tissue. The X-ray absorption by skin tissue is large under the diffracted X-rays detected in low angles because the length of penetration depends on the angle of inclination, equal to the Bragg angle. The effects of skin tissue to detect the diffracted X-rays were investigated in the experiments. And the strain measurements were conducted under bending loads applied to the Ti specimen. The effect of skin tissue was absorption of X-rays as well as the X-rays scattered from the physiological saline contained in the tissue. The X-rays scattered by the physiological saline creates a specific background pattern near the peaks from the (002) and (011) lattice planes of Ti in the X-ray diffraction profile. Diffracted X-rays from the Ti were detected after being transmitted through 1 mm thick skin tissue by Mo Kalpha. Individual peaks such as (010), (002), (011), and (110) were clearly established by using a parallel beam arrangement. The strains of (110) lattice planes were measured with or without the tissue cover were very similar. The strain of the (110) lattice planes of Ti could be measured by Mo Kalpha when the Ti specimen was located under the skin tissue. PMID:20459192

  12. Diffraction grating transmission efficiencies for XUV and soft X rays. [for HEAO-B extrasolar astronomy

    NASA Technical Reports Server (NTRS)

    Schnopper, H. W.; Van Speybroeck, L. P.; Delvaille, J. P.; Epstein, A.; Kaellne, E.; Bachrach, R. Z.; Dijkstra, J.; Lantward, L.

    1977-01-01

    The manufacture and properties of a grating intended for extrasolar X-ray studies are described. The manufacturing process uses a split laser beam exposing an interference pattern on the photoresist-coated glass plated with a nickel parting layer. The grating, supporting structure, and mounting frame are electrodeposited on the nickel parting layer, and the final product is lifted from the glass substrate by selective etching of the nickel. A model was derived which relates the number of counts received in a given order m as a function of photon wavenumber. A 4-deg beam line was used to measure the efficiencies of gold transmission gratings for diffraction of X-rays in the range of 45 to 275 eV. The experimental results are in good agreement with model calculations.

  13. Diffraction and imaging study of imperfections of crystallized lysozyme with coherent X-rays

    NASA Technical Reports Server (NTRS)

    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 <1 1 0> 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.

  14. Capability of X-ray diffraction for the study of microstructure of metastable thin films.

    PubMed

    Rafaja, David; Wüstefeld, Christina; Dopita, Milan; Motylenko, Mykhaylo; Baehtz, Carsten

    2014-11-01

    Metastable phases are often used to design materials with outstanding properties, which cannot be achieved with thermodynamically stable compounds. In many cases, the metastable phases are employed as precursors for controlled formation of nanocomposites. This contribution shows how the microstructure of crystalline metastable phases and the formation of nanocomposites can be concluded from X-ray diffraction experiments by taking advantage of the high sensitivity of X-ray diffraction to macroscopic and microscopic lattice deformations and to the dependence of the lattice deformations on the crystallographic direction. The lattice deformations were determined from the positions and from the widths of the diffraction lines, the dependence of the lattice deformations on the crystallographic direction from the anisotropy of the line shift and the line broadening. As an example of the metastable system, the supersaturated solid solution of titanium nitride and aluminium nitride was investigated, which was prepared in the form of thin films by using cathodic arc evaporation of titanium and aluminium in a nitrogen atmosphere. The microstructure of the (Ti,Al)N samples under study was tailored by modifying the [Al]/[Ti] ratio in the thin films and the surface mobility of the deposited species. PMID:25485125

  15. Note: Electrochemical cell for in operando X-ray diffraction measurements on a conventional X-ray diffractometer

    NASA Astrophysics Data System (ADS)

    Hartung, Steffen; Bucher, Nicolas; Bucher, Ramona; Srinivasan, Madhavi

    2015-08-01

    Electrochemical in operando X-ray diffraction (XRD) is a powerful method to analyze structural changes of energy storage materials while inserting/de-inserting charge carriers, such as Li- or Na-ions, into/from a host structure. The design of an XRD in operando cell is presented, which enables the use of thin (6 μm) aluminum foil as X-ray window as a non-toxic alternative to conventional beryllium windows. Owing to the reduced thickness, diffraction patterns and their changes during cycling can be observed with excellent quality, which was demonstrated for two cathode materials for sodium-ion batteries in a half-cell set-up, P2-Na0.7MnO2 and Na2.55V6O16 ṡ 0.6H2O.

  16. Note: Electrochemical cell for in operando X-ray diffraction measurements on a conventional X-ray diffractometer.

    PubMed

    Hartung, Steffen; Bucher, Nicolas; Bucher, Ramona; Srinivasan, Madhavi

    2015-08-01

    Electrochemical in operando X-ray diffraction (XRD) is a powerful method to analyze structural changes of energy storage materials while inserting/de-inserting charge carriers, such as Li- or Na-ions, into/from a host structure. The design of an XRD in operando cell is presented, which enables the use of thin (6 μm) aluminum foil as X-ray window as a non-toxic alternative to conventional beryllium windows. Owing to the reduced thickness, diffraction patterns and their changes during cycling can be observed with excellent quality, which was demonstrated for two cathode materials for sodium-ion batteries in a half-cell set-up, P2-Na(0.7)MnO2 and Na(2.55)V6O16 ⋅ 0.6H2O. PMID:26329242

  17. Note: Electrochemical cell for in operando X-ray diffraction measurements on a conventional X-ray diffractometer

    SciTech Connect

    Hartung, Steffen; Bucher, Nicolas; Bucher, Ramona; Srinivasan, Madhavi

    2015-08-15

    Electrochemical in operando X-ray diffraction (XRD) is a powerful method to analyze structural changes of energy storage materials while inserting/de-inserting charge carriers, such as Li- or Na-ions, into/from a host structure. The design of an XRD in operando cell is presented, which enables the use of thin (6 μm) aluminum foil as X-ray window as a non-toxic alternative to conventional beryllium windows. Owing to the reduced thickness, diffraction patterns and their changes during cycling can be observed with excellent quality, which was demonstrated for two cathode materials for sodium-ion batteries in a half-cell set-up, P2-Na{sub 0.7}MnO{sub 2} and Na{sub 2.55}V{sub 6}O{sub 16} ⋅ 0.6H{sub 2}O.

  18. Coherent X-Ray Diffraction Imaging of Chloroplasts from Cyanidioschyzon merolae by Using X-Ray Free Electron Laser.

    PubMed

    Takayama, Yuki; Inui, Yayoi; Sekiguchi, Yuki; Kobayashi, Amane; Oroguchi, Tomotaka; Yamamoto, Masaki; Matsunaga, Sachihiro; Nakasako, Masayoshi

    2015-07-01

    Coherent X-ray diffraction imaging (CXDI) is a lens-less technique for visualizing the structures of non-crystalline particles with the dimensions of submicrometer to micrometer at a resolution of several tens of nanometers. We conducted cryogenic CXDI experiments at 66 K to visualize the internal structures of frozen-hydrated chloroplasts of Cyanidioschyzon merolae using X-ray free electron laser (XFEL) as a coherent X-ray source. Chloroplast dispersed specimen disks at a number density of 7/(10×10 µm(2)) were flash-cooled with liquid ethane without staining, sectioning or chemical labeling. Chloroplasts are destroyed at atomic level immediately after the diffraction by XFEL pulses. Thus, diffraction patterns with a good signal-to-noise ratio from single chloroplasts were selected from many diffraction patterns collected through scanning specimen disks to provide fresh specimens into the irradiation area. The electron density maps of single chloroplasts projected along the direction of the incident X-ray beam were reconstructed by using the iterative phase-retrieval method and multivariate analyses. The electron density map at a resolution of 70 nm appeared as a C-shape. In addition, the fluorescence image of proteins stained with Flamingo™ dye also appeared as a C-shape as did the autofluorescence from Chl. The similar images suggest that the thylakoid membranes with an abundance of proteins distribute along the outer membranes of chloroplasts. To confirm the present results statistically, a number of projection structures must be accumulated through high-throughput data collection in the near future. Based on the results, we discuss the feasibility of XFEL-CXDI experiments in the structural analyses of cellular organelles. PMID:25745031

  19. Lensless Diffractive Imaging Using Tabletop Coherent High-Harmonic Soft-X-Ray Beams

    SciTech Connect

    Sandberg, Richard L.; Paul, Ariel; Raymondson, Daisy A.; Haedrich, Steffen; Gaudiosi, David M.; Holtsnider, Jim; Tobey, Ra'anan I.; Cohen, Oren; Murnane, Margaret M.; Kapteyn, Henry C.; Song, Changyong; Miao Jianwei; Liu Yanwei; Salmassi, Farhad

    2007-08-31

    We present the first experimental demonstration of lensless diffractive imaging using coherent soft x rays generated by a tabletop soft-x-ray source. A 29 nm high harmonic beam illuminates an object, and the subsequent diffraction is collected on an x-ray CCD camera. High dynamic range diffraction patterns are obtained by taking multiple exposures while blocking small-angle diffraction using beam blocks of varying size. These patterns reconstruct to images with 214 nm resolution. This work demonstrates a practical tabletop lensless microscope that promises to find applications in materials science, nanoscience, and biology.

  20. High-resolution projection image reconstruction of thick objects by hard x-ray diffraction microscopy

    SciTech Connect

    Takahashi, Yukio; Nishino, Yoshinori; Tsutsumi, Ryosuke; Zettsu, Nobuyuki; Matsubara, Eiichiro; Yamauchi, Kazuto; Ishikawa, Tetsuya

    2010-12-01

    Hard x-ray diffraction microscopy enables us to observe thick objects at high spatial resolution. The resolution of this method is limited, in principle, by only the x-ray wavelength and the largest scattering angle recorded. As the resolution approaches the wavelength, the thickness effect of objects plays a significant role in x-ray diffraction microscopy. In this paper, we report high-resolution hard x-ray diffraction microscopy for thick objects. We used highly focused coherent x rays with a wavelength of {approx}0.1 nm as an incident beam and measured the diffraction patterns of a {approx}150-nm-thick silver nanocube at the scattering angle of {approx}3 deg. We observed a characteristic contrast of the coherent diffraction pattern due to only the thickness effect and collected the diffraction patterns at nine incident angles so as to obtain information on a cross section of Fourier space. We reconstructed a pure projection image by the iterative phasing method from the patched diffraction pattern. The edge resolution of the reconstructed image was {approx}2 nm, which was the highest resolution so far achieved by x-ray microscopy. The present study provides us with a method for quantitatively observing thick samples at high resolution by hard x-ray diffraction microscopy.

  1. Real-time x-ray diffraction measurements of shocked polycrystalline tin and aluminum.

    PubMed

    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 K(alpha) 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 K(beta) line emission. The x-ray beam passes through a pinhole collimator and is incident on the sample with an approximately 3 x 6 mm(2) spot and 1 degrees 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 degrees . 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. PMID:19045900

  2. Real-time X-ray Diffraction Measurements of Shocked Polycrystalline Tin and Aluminum

    SciTech Connect

    Dane V. Morgan, Don Macy, Gerald Stevens

    2008-11-22

    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-mm by 6-mm spot and 1° full-width-half-maximum (FWHM) 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 (CCD) camera through a coherent fiberoptic 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 (fcc) aluminum lattice with no phase transformation.

  3. X-ray test facility for diffraction gratings

    NASA Astrophysics Data System (ADS)

    McEntaffer, Randall L.; Hearty, Fred R.; Gleeson, Brian; Cash, Webster C.

    2004-02-01

    The University of Colorado maintains a grating evaluation facility to characterize optics from the far ultraviolet to the X-ray. The newest addition to this facility is a novel X-ray monochromator. Light is generated by a Manson electron impact X-ray source and passes through a monochromator which incorporates a grating in the off-plane mount at grazing incidence followed by an aluminum filter. From here, the light enters another vacuum chamber to illuminate the test grating, which disperses light onto a resistive anode MCP. This monochromator is characterized utilizing a variety of source anodes and voltages. Preliminary results from a high density test grating, also in the off-plane mount, display that this system is a highly effective tool for determining grating efficiencies.

  4. Single order X-ray diffraction with binary sinusoidal transmission grating

    NASA Astrophysics Data System (ADS)

    Cao, Leifeng

    2013-10-01

    All existing x-ray dispersive devices including crystals, multilayers and diffraction gratings generate spectra in multiple orders, whereas soft x-ray spectroscopy applications usually require only the first order spectrum. The other diffraction orders can overlap and contaminate the first order spectrum of interest. In this letter we describe how an axis-symmetrically-distributed sinusoidal-shaped aperture with binary transmittance values can be used to disperse x-rays and with a superior diffraction pattern where, along its symmetry axis, all higher-order diffractions can be effectively suppressed. Hence this sophisticated dispersive element generates pure soft x-ray spectra in the first diffraction order, free from interference from higher diffraction orders.

  5. Detectors for X-ray diffraction and scattering: a user's overview

    NASA Astrophysics Data System (ADS)

    Brügemann, Lutz; Gerndt, Ekkehard K. E.

    2004-09-01

    An overview of the applications of X-ray detectors to material research is given. Four experimental techniques and their specific detector requirements are described. Detector types are classified and critical parameters described in the framework of X-ray diffraction and X-ray scattering experiments. The article aims at building a bridge between detector end-users and detector developers. It gives limits of critical detector parameters, like angular resolution, energy resolution, dynamic range, and active area.

  6. DIIS: A cross-platform program for the reduction of X-ray diffraction data from a cylindrical area detector

    NASA Astrophysics Data System (ADS)

    Petrus, J. A.; Ross, K. C.; McDonald, A. M.

    2012-01-01

    A new program capable of rapidly and accurately reducing a two-dimensional X-ray diffraction pattern obtained from a Debye-Scherrer or Gandolfi camera to a quantitative digital diffractogram is described. By implementing geometric optimization routines based on the symmetry and sharpness of diffraction lines, the optimal configuration of the camera, X-ray path, and sample can be determined, thus providing the best possible set of integration parameters. Results for NIST standard reference materials 640c (Si) and 676 (Al 2O 3) are included to illustrate program functionality.

  7. X-Ray Spectrum of a Narrow-Line QSO

    NASA Technical Reports Server (NTRS)

    Halpern, Jules P.

    1998-01-01

    During the reporting period, seven papers using ASCA data, supported in whole or in part by this grant, were published or submitted to refereed journals. Their abstracts are given in this report, and the complete bibliographic references are listed in the Appendix. Titles include (1) A Broad-Band X-ray Study of the Geminga Pulsar; (2) ASCA Observations of PSR 1920+10 and PSR 0950+08; (3) X-ray and Optical Spectroscopy of IRAS 20181-2244: Not a Type 2 QSO, but a I Zw I Object; (4) Models for X-ray Emission from Isolated Pulsars; (5) Optical and X-ray Spectroscopy of 1E 0449.4-1823: Demise of the Original Type 2 QSO; (6) The ASCA Spectrum of the Broad-Line Radio Galaxy Pictor A: A Simple Power Law with No Fe Ka Line; and (7) ASCA Spectra of NGC 4388 and ESO 103-G35: Absorption, Reflection, and Variability in Intermediate Type Seyfert Galaxies.

  8. (X-ray diffraction experiments with condenser matter)

    SciTech Connect

    Coppens, P.

    1990-01-01

    This report discusses research on the following topics: high-{Tc} superconductors; The response of crystal to an applied electric field; quasicrystals; surface structure and kinetics of surface layer formation; EXAFS studies of superconductors and heterostructures; effect of iron on the crystal structure of perovskite; x-ray detector development; and SAXS experiments. (LSP)

  9. Setup for in situ X-ray diffraction studies of thin film growth by magnetron sputtering

    NASA Astrophysics Data System (ADS)

    Ellmer, K.; Mientus, R.; Weiß, V.; Rossner, H.

    2001-07-01

    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° and 10°, 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.

  10. A Bayesian Approach to Surface X-ray Diffraction

    SciTech Connect

    Lyman, Paul F.; Saldin, Dilano K.

    2006-11-17

    We report on the development of an iterative method to directly invert surface x-ray diffraction (SXRD) data and thereby provide a map of electron density in the near-surface region of a solid. We have termed this method PARADIGM, which stands for Phase and Amplitude Recovery And Diffraction Image Generation Method. Significant advances in the PARADIGM theory were made during the grant period, and experimental milestones have also been achieved. The two components of the research program worked in concert, each spurring progress in the other. The method works by iteratively recovering the phases of surface scattering factors. Initially, random phases are assigned to the structure factors. After subtracting off the known bulk component, a Fourier transform converts these factors into an estimate of the real-space electron density map. This map is subjected to a support constraint, which holds that the electron density may only be non-zero near the solid surface. The modified electron density is then subjected to an inverse Fourier transform, and the bulk contributions are added back in. This renders an improved estimate of the phases of the surface structure factors. A constraint in reciprocal space is then applied, namely, the amplitudes of the scattering factors are set equal to the experimentally observed ones. This cycle is repeated, transforming between real and reciprocal space and applying constraints in each, until convergence is reached. The result renders a good initial model of the unknown surface structure. Such a direct method is important because conventional structural refinement methods rely on having a guess of the starting structure that sufficiently good that it may be refined into a model with the correct atomic positions. If the starting model has, for example, the wrong number or identity of atoms in the surface unit cell, it can never refine to the correct model. Even in cases where the starting model contains the correct number and identity

  11. Hard X-ray imaging of bacterial cells: nano-diffraction and ptychographic reconstruction.

    PubMed

    Wilke, R N; Priebe, M; Bartels, M; Giewekemeyer, K; Diaz, A; Karvinen, P; Salditt, T

    2012-08-13

    Ptychographic coherent X-ray diffractive imaging (PCDI) has been combined with nano-focus X-ray diffraction to study the structure and density distribution of unstained and unsliced bacterial cells, using a hard X-ray beam of 6.2keV photon energy, focused to about 90nm by a Fresnel zone plate lens. While PCDI provides images of the bacteria with quantitative contrast in real space with a resolution well below the beam size at the sample, spatially resolved small angle X-ray scattering using the same Fresnel zone plate (cellular nano-diffraction) provides structural information at highest resolution in reciprocal space up to 2nm(-1). We show how the real and reciprocal space approach can be used synergistically on the same sample and with the same setup. In addition, we present 3D hard X-ray imaging of unstained bacterial cells by a combination of ptychography and tomography. PMID:23038565

  12. X-ray Diffraction Crystal Calibration and Characterization

    SciTech Connect

    Michael J. Haugh; Richard Stewart; Nathan Kugland

    2009-06-05

    National Security Technologies’ X-ray Laboratory is comprised of a multi-anode Manson type source and a Henke type source that incorporates a dual goniometer and XYZ translation stage. The first goniometer is used to isolate a particular spectral band. The Manson operates up to 10 kV and the Henke up to 20 kV. The Henke rotation stages and translation stages are automated. Procedures have been developed to characterize and calibrate various NIF diagnostics and their components. The diagnostics include X-ray cameras, gated imagers, streak cameras, and other X-ray imaging systems. Components that have been analyzed include filters, filter arrays, grazing incidence mirrors, and various crystals, both flat and curved. Recent efforts on the Henke system are aimed at characterizing and calibrating imaging crystals and curved crystals used as the major component of an X-ray spectrometer. The presentation will concentrate on these results. The work has been done at energies ranging from 3 keV to 16 keV. The major goal was to evaluate the performance quality of the crystal for its intended application. For the imaging crystals we measured the laser beam reflection offset from the X-ray beam and the reflectivity curves. For the curved spectrometer crystal, which was a natural crystal, resolving power was critical. It was first necessary to find sources of crystals that had sufficiently narrow reflectivity curves. It was then necessary to determine which crystals retained their resolving power after being thinned and glued to a curved substrate.

  13. Observing soft X-ray line emission from the interstellar medium with X-ray calorimeter on a sounding rocket

    NASA Technical Reports Server (NTRS)

    Zhang, J.; Edwards, B.; Juda, M.; Mccammon, D.; Skinner, M.; Kelley, R.; Moseley, H.; Schoelkopf, R.; Szymkowiak, A.

    1990-01-01

    For an X-ray calorimeter working at 0.1 K, the energy resolution ideally can be as good as one eV for a practical detector. A detector with a resolution of 17 eV FWHM at 6 keV has been constructed. It is expected that this can be improved by a factor of two or more. With X-ray calorimeters flown on a sounding rocket, it should be possible to observe soft X-ray line emission from the interstellar medium over the energy range 0.07 to 1 keV. Here, a preliminary design for an X-ray calorimeter rocket experiment and the spectrum which might be observed from an equilibrium plasma are presented. For later X-ray calorimeter sounding rocket experiments, it is planned to add an aluminum foil mirror with collecting area of about 400 sq cm to observe line features from bright supernova remnants.

  14. High Resolution X-Ray Diffraction of Macromolecules with Synchrotron Radiation

    NASA Technical Reports Server (NTRS)

    Stojanoff, Vivian; Boggon, Titus; Helliwell, John R.; Judge, Russell; Olczak, Alex; Snell, Edward H.; Siddons, D. Peter; Rose, M. Franklin (Technical Monitor)

    2000-01-01

    We recently combined synchrotron-based monochromatic X-ray diffraction topography methods with triple axis diffractometry and rocking curve measurements: high resolution X-ray diffraction imaging techniques, to better understand the quality of protein crystals. We discuss these methods in the light of results obtained on crystals grown under different conditions. These non destructive techniques are powerful tools in the characterization of the protein crystals and ultimately will allow to improve, develop, and understand protein crystal growth. High resolution X-ray diffraction imaging methods will be discussed in detail in light of recent results obtained on Hen Egg White Lysozyme crystals and other proteins.

  15. Anti-contamination device for cryogenic soft X-ray diffraction microscopy

    DOE PAGESBeta

    Huang, Xiaojing; Miao, Huijie; Nelson, Johanna; Turner, Joshua; Steinbrener, Jan; Shapiro, David; Kirz, Janos; Jacobsen, Chris

    2011-05-01

    Cryogenic microscopy allows one to view frozen hydrated biological and soft matter specimens with good structural preservation and a high degree of stability against radiation damage. We describe a liquid nitrogen-cooled anti-contamination device for cryogenic X-ray diffraction microscopy. The anti-contaminator greatly reduces the buildup of ice layers on the specimen due to condensation of residual water vapor in the experimental vacuum chamber. We show by coherent X-ray diffraction measurements that this leads to fivefold reduction of background scattering, which is important for far-field X-ray diffraction microscopy of biological specimens.

  16. Temperature-dependent vibrational spectroscopic and X-ray diffraction investigation of nanosized nickel chromite

    NASA Astrophysics Data System (ADS)

    Matulková, Irena; Holec, Petr; Němec, Ivan; Kitazawa, Hideaki; Furubayashi, Takao; Vejpravová, Jana

    2015-06-01

    The nanocrystalline nickel chromite (NiCr2O4) with particle size of ∼20 nm was prepared by auto-combustion method. The nanocrystals were characterized by powder X-ray diffraction, vibrational spectroscopy and magnetic measurements. The expected structural phase transitions (cubic-tetragonal-orthorhombic) were studied by methods of temperature-dependent X-ray powder diffraction and vibrational spectroscopy. The evolution of the Raman spectra and X-ray diffraction patterns collected from 350 K down to 4 K confirmed the cubic-to-tetragonal distortion at ∼250 K, whereas the tetragonal-to-orthorhombic transition was not confirmed in the nanocrystalline sample.

  17. Nanoscale Imaging of Buried Structures with Elemental Specificity Using Resonant X-Ray Diffraction Microscopy

    SciTech Connect

    Song, Changyong; Bergstrom, Raymond; Ramunno-Johnson, Damien; Jiang, Huaidong; Miao, Jianwei; Paterson, David; Jonge, Martin D. de; McNulty, Ian; Lee, Jooyoung; Wang, Kang L.

    2008-01-18

    We report the first demonstration of resonant x-ray diffraction microscopy for element specific imaging of buried structures with a pixel resolution of {approx}15 nm by exploiting the abrupt change in the scattering cross section near electronic resonances. We performed nondestructive and quantitative imaging of buried Bi structures inside a Si crystal by directly phasing coherent x-ray diffraction patterns acquired below and above the Bi M{sub 5} edge. We anticipate that resonant x-ray diffraction microscopy will be applied to element and chemical state specific imaging of a broad range of systems including magnetic materials, semiconductors, organic materials, biominerals, and biological specimens.

  18. Nanofabrication of diffractive optics for soft X-ray and atom beam focusing

    NASA Astrophysics Data System (ADS)

    Rehbein, S.

    2003-03-01

    Nanostructuring processes are described for manufacturing diffractive optics for the condensermonochromator set-up of the transmission X-ray microscope (TXM) and for the scanning transmission X-ray microscope (STXM) at the BESSY II electron storage ring in Berlin. Furthermore, a process for manufacturing freestanding nickel zone plates for helium atom beam focusing experiments is presented.

  19. Influence of conversion material morphology on electrochemistry studied with operando X-ray tomography and diffraction.

    PubMed

    Villevieille, Claire; Ebner, Martin; Gómez-Cámer, Juan Luis; Marone, Federica; Novák, Petr; Wood, Vanessa

    2015-03-11

    X-ray diffraction and X-ray tomography are performed on intermetallic particles undergoing lithiation in a porous electrode. Differences between ensemble phase evolution and that at a single-particle level are explored. It is found that all particles evidence core-shell lithiation; however, particles with internal porosity are more mechanically robust and exhibit less fracture. PMID:25619158

  20. K alpha line emission during solar X-ray bursts

    NASA Technical Reports Server (NTRS)

    Phillips, K. J. H.; Neupert, W. M.

    1973-01-01

    The expected flux of K alpha line emission from sulfur, argon, calcium, and iron is calculated during both thermal and nonthermal solar X-ray events. Such emission is shown to be weak during the course of most of the nonthermal hard X-ray bursts that Kane and Anderson (1970) have observed. If Compton backscattering is significant at high energies, the flux is reduced still further for disk flares, but it is noted that the strong, near-limb burst of June 26 would have produced about 100 photons /sq cm/sec of sulfur and iron K alpha emission. The impulsive hard X-ray bursts may in general be too short-lived for much K alpha emission. It may be noted that sulfur K alpha emission in particular depends sensitively on the lower-energy limit of the nonthermal electron spectrum, assuming such a sharply defined boundary exists. During soft X-ray bursts, when temperatures of a few 10 to the 7th power K are obtained, K alpha emission from certain iron ions, specifically Fe XVIII-XXIII, may be important.

  1. On-Line Mirror Surfacing Monitored by X-ray Shearing Interferometry and X-ray Scattering

    SciTech Connect

    Ziegler, E.; Peverini, L.; Kozhevnikov, I. V.; Weitkamp, T.; David, C.

    2007-01-19

    We propose a novel fabrication scheme combining a mirror surfacing tool and an on-line metrology instrument, the latter capable of controlling both figure and finish of an X-ray mirror with an accuracy matching the challenging specifications of nanofocusing reflective optics for synchrotron and FEL X-ray beams. This approach will be complementary to the present technologies. The paper reviews some recent achievements and presents pertinent examples of on-line diagnostics performed at the ESRF BM05 beamline for which X-rays prove to be a unique probe.

  2. X-Ray Diffraction Powder Patterns and Thin Section Observations from the Sierra Madera Impact Structure

    NASA Astrophysics Data System (ADS)

    Huson, S. A.; Foit, F. F.; Watkinson, A. J.; Pope, M. C.

    2006-03-01

    X-Ray powder diffraction analysis and thin section observations of carbonate and siliciclastic samples from the Sierra Madera impact structure indicate moderate shock pressures (8 to 30 GPa) were generated during the formation of this crater.

  3. Electrochemical in-situ reaction cell for X-ray scattering, diffraction and spectroscopy

    SciTech Connect

    Braun, Artur; Granlund, Eric; Cairns, Elton J.

    2003-01-27

    An electrochemical in-situ reaction cell for hard X-ray experiments with battery electrodes is described. Applications include the small angle scattering, diffraction, and near-edge spectroscopy of lithium manganese oxide electrodes.

  4. Equation of state of solid neon from x-ray diffraction measurements to 110 GPa

    SciTech Connect

    Hemley, R.J.; Jephcoat, A.P.; Zha, C.S.; Mao, H.K.; Finger, L.W.; Cox, D.E.

    1987-01-01

    This paper briefly discusses the pressure-volume properties of condensed neon. X-ray diffraction techniques are used to determine solid neon equation of state and crystal structure. 16 refs., 2 figs. (LSP)

  5. State-of-the-art and problems of X-ray diffraction analysis of biomacromolecules

    SciTech Connect

    Andreeva, N. S.

    2006-12-15

    The state-of-the-art of X-ray diffraction studies of biomacromolecules is briefly characterized, and the challenge imposed by science is discussed. These studies are characterized by a wide scope and extensive use. This field of science is of great interest and is developed in many countries. The main purpose is to solve practical problems in medicine consisting in the design of drugs against various diseases. X-ray diffraction analysis of enzymes brought the pharmaceutical industry to a new level, thus allowing the rational design of drugs against formerly untreatable diseases. Modern X-ray diffraction studies of biomacromolecules laid the basis for a new science called structural biology. This method allows one to solve fundamental problems of physical chemistry for a new state of matter existing in living systems. Here, science poses numerous problems in analysis of X-ray diffraction data on biological macromolecules. Many of theses problems are in their infancy.

  6. [Research on the silk aging with x-ray diffraction spectra].

    PubMed

    Zhang, Xiao-mei; Yuan, Si-xun

    2010-01-01

    The present paper did some researches on the deterioration mechanism and the changes in crystallinity of silk fabrics by means of the X-ray diffraction analysis. The samples artificially aged and excavated from Hubei, Innermongolia, Shaanxi and Qinghai provinces were analyzed. The artificial aging was done by simulating three main natural aging factors: light, heat and hydrolysis. The analytical results show that X-ray diffraction analysis could reveal the aging process and characteristic of silk, as well as the changes in crystallinity during silk aging. The X-ray diffraction analysis is of practical value for the conservation state and aging mechanism studies of ancient silk. In addition, X-ray diffraction analysis could also provide important information on ancient technology of textile and apparel. PMID:20302128

  7. State-of-the-art and problems of X-ray diffraction analysis of biomacromolecules

    NASA Astrophysics Data System (ADS)

    Andreeva, N. S.

    2006-12-01

    The state-of-the-art of X-ray diffraction studies of biomacromolecules is briefly characterized, and the challenge imposed by science is discussed. These studies are characterized by a wide scope and extensive use. This field of science is of great interest and is developed in many countries. The main purpose is to solve practical problems in medicine consisting in the design of drugs against various diseases. X-ray diffraction analysis of enzymes brought the pharmaceutical industry to a new level, thus allowing the rational design of drugs against formerly untreatable diseases. Modern X-ray diffraction studies of biomacromolecules laid the basis for a new science called structural biology. This method allows one to solve fundamental problems of physical chemistry for a new state of matter existing in living systems. Here, science poses numerous problems in analysis of X-ray diffraction data on biological macromolecules. Many of theses problems are in their infancy.

  8. Method for improve x-ray diffraction determinations of residual stress in nickel-base alloys

    DOEpatents

    Berman, Robert M.; Cohen, Isadore

    1990-01-01

    A process for improving the technique of measuring residual stress by x-ray diffraction in pieces of nickel-base alloys which comprises covering part of a predetermined area of the surface of a nickel-base alloy with a dispersion, exposing the covered and uncovered portions of the surface of the alloy to x-rays by way of an x-ray diffractometry apparatus, making x-ray diffraction determinations of the exposed surface, and measuring the residual stress in the alloy based on these determinations. The dispersion is opaque to x-rays and serves a dual purpose since it masks off unsatisfactory signals such that only a small portion of the surface is measured, and it supplies an internal standard by providing diffractogram peaks comparable to the peaks of the nickel alloy so that the alloy peaks can be very accurately located regardless of any sources of error external to the sample.

  9. Method for improving x-ray diffraction determinations of residual stress in nickel-base alloys

    DOEpatents

    Berman, R.M.; Cohen, I.

    1988-04-26

    A process for improving the technique of measuring residual stress by x-ray diffraction in pieces of nickel-base alloys is discussed. Part of a predetermined area of the surface of a nickel-base alloy is covered with a dispersion. This exposes the covered and uncovered portions of the surface of the alloy to x-rays by way of an x-ray diffractometry apparatus, making x-ray diffraction determinations of the exposed surface, and measuring the residual stress in the alloy based on these determinations. The dispersion is opaque to x-rays and serves a dual purpose, since it masks off unsatisfactory signals such that only a small portion of the surface is measured, and it supplies an internal standard by providing diffractogram peaks comparable to the peaks of the nickel alloy so that the alloy peaks can be very accurately located regardless of any sources of error external to the sample. 2 figs.

  10. X-ray diffraction observations of chemically skinned frog skeletal muscle processed by an improved method.

    PubMed Central

    Magid, A; Reedy, M K

    1980-01-01

    Whole frog sartorius muscles can be chemically skinned in approximately 2 h by relaxing solutions containing 0.5% Triton X-100. The intensity and order of the X-ray diffraction pattern from living muscle is largely retained after such skinning, indicating good retention of native structure in fibrils and filaments. Best X-ray results were obtained using a solution with (mM): 75 K acetate; 5 Mg acetate; 5 ATP; 5 EGTA; 15 K phosphate, 2% PVP, pH 7.0. Equatorial X-ray patterns showed that myofibrils swell after detergent skinning, as also observed after mechanical skinning. This swelling could be reversed by adding high molecular weight colloids (PVP or dextran) to the extracting solution. By finding the colloid osmotic pressure needed to restore the in vivo interfilament spacing (3% PVP, 4 X 10(4) mol wt) the swelling pressure was estimated as 35 Torr in a standard KCl-based relaxing solution. The swelling pressure and the extent of swelling were less than acetate replaced chloride as the major anion. Detergent-skinned muscle lost the constant-volume relation between sarcomere length and lattice spacing seen in intact muscle. Changes in A band spacing were paralleled by changes in I and band-Z line spacing at a constant sarcomere length. After detergent skinning, I1,0 rose while I1,1 fell, a change in the relaxing direction. Since raising the calcium ion concentrations from pCa 9 to PCa 6.7 was without effect on equatorial or axial X-ray patterns, we concluded that these intensity changes were not due to calcium-dependent cross-bridge movement but rather to disordering of thin filaments in the A band. Images FIGURE 2 FIGURE 1 PMID:6973364

  11. Time-resolved x-ray diffraction study of photostimulated purple membrane.

    PubMed Central

    Frankel, R D; Forsyth, J M

    1985-01-01

    A nanosecond resolution laser-driven x-ray source has been used to perform a time-resolved, x-ray diffraction study of the purple membrane of the Halobacterium halobium. Alterations in diffraction patterns have been observed 1 ms after photostimulation, and are interpreted to show disorder of bacteriorhodopsin packing in the plane of the membrane with little bacteriorhodopsin structural change. PMID:3978209

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

    SciTech Connect

    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.

  13. Measurement of piezoelectric constants of lanthanum-gallium tantalate crystal by X-ray diffraction methods

    SciTech Connect

    Blagov, A. E.; Marchenkov, N. V. Pisarevsky, Yu. V.; Prosekov, P. A.; Kovalchuk, M. V.

    2013-01-15

    A method for measuring piezoelectric constants of crystals of intermediate systems by X-ray quasi-multiple-wave diffraction is proposed and implemented. This technique makes it possible to determine the piezoelectric coefficient by measuring variations in the lattice parameter under an external electric field. This method has been approved, its potential is evaluated, and a comparison with high-resolution X-ray diffraction data is performed.

  14. Three-Dimensional Visualization of a Human Chromosome Using Coherent X-Ray Diffraction

    SciTech Connect

    Nishino, Yoshinori; Ishikawa, Tetsuya; Takahashi, Yukio; Imamoto, Naoko; Maeshima, Kazuhiro

    2009-01-09

    Coherent x-ray diffraction microscopy is a lensless phase-contrast imaging technique with high image contrast. Although electron tomography allows intensive study of the three-dimensional structure of cellular organelles, it has inherent difficulty with thick objects. X rays have the unique benefit of allowing noninvasive analysis of thicker objects and high spatial resolution. We observed an unstained human chromosome using coherent x-ray diffraction. The reconstructed images in two or three dimensions show an axial structure, which has not been observed under unstained conditions.

  15. An atomic layer deposition chamber for in situ x-ray diffraction and scattering analysis

    SciTech Connect

    Geyer, Scott M.; Methaapanon, Rungthiwa; Kim, Woo-Hee; Bent, Stacey F.; Johnson, Richard W.; Van Campen, Douglas G.; Metha, Apurva

    2014-05-15

    The crystal structure of thin films grown by atomic layer deposition (ALD) will determine important performance properties such as conductivity, breakdown voltage, and catalytic activity. We report the design of an atomic layer deposition chamber for in situ x-ray analysis that can be used to monitor changes to the crystal structural during ALD. The application of the chamber is demonstrated for Pt ALD on amorphous SiO{sub 2} and SrTiO{sub 3} (001) using synchrotron-based high resolution x-ray diffraction, grazing incidence x-ray diffraction, and grazing incidence small angle scattering.

  16. A portable X-ray diffraction apparatus for in situ analyses of masters' paintings

    NASA Astrophysics Data System (ADS)

    Eveno, Myriam; Duran, Adrian; Castaing, Jacques

    2010-09-01

    It is rare that the analyses of materials in paintings can be carried out by taking micro-samples. Valuable works of art are best studied in situ by non-invasive techniques. For that purpose, a portable X-ray diffraction and fluorescence apparatus has been designed and constructed at the C2RMF. This apparatus has been used for paintings of Rembrandt, Leonardo da Vinci, Van Gogh, Mantegna, etc. Results are given to illustrate the performance of X-ray diffraction, especially when X-ray fluorescence does not bring sufficient information to conclude.

  17. Reactive sputter magnetron reactor for preparation of thin films and simultaneous in situ structural study by X-ray diffraction.

    PubMed

    Bürgi, J; Neuenschwander, R; Kellermann, G; García Molleja, J; Craievich, A F; Feugeas, J

    2013-01-01

    The purpose of the designed reactor is (i) to obtain polycrystalline and∕or amorphous thin films by controlled deposition induced by a reactive sputtering magnetron and (ii) to perform a parallel in situ structural study of the deposited thin films by X-ray diffraction, in real time, during the whole growth process. The designed reactor allows for the control and precise variation of the relevant processing parameters, namely, magnetron target-to-sample distance, dc magnetron voltage, and nature of the gas mixture, gas pressure and temperature of the substrate. On the other hand, the chamber can be used in different X-ray diffraction scanning modes, namely, θ-2θ scanning, fixed α-2θ scanning, and also low angle techniques such as grazing incidence small angle X-ray scattering and X-ray reflectivity. The chamber was mounted on a standard four-circle diffractometer located in a synchrotron beam line and first used for a preliminary X-ray diffraction analysis of AlN thin films during their growth on the surface of a (100) silicon wafer. PMID:23387690

  18. Reactive sputter magnetron reactor for preparation of thin films and simultaneous in situ structural study by X-ray diffraction

    SciTech Connect

    Buergi, J.; Molleja, J. Garcia; Feugeas, J.; Neuenschwander, R.; Kellermann, G.; Craievich, A. F.

    2013-01-15

    The purpose of the designed reactor is (i) to obtain polycrystalline and/or amorphous thin films by controlled deposition induced by a reactive sputtering magnetron and (ii) to perform a parallel in situ structural study of the deposited thin films by X-ray diffraction, in real time, during the whole growth process. The designed reactor allows for the control and precise variation of the relevant processing parameters, namely, magnetron target-to-sample distance, dc magnetron voltage, and nature of the gas mixture, gas pressure and temperature of the substrate. On the other hand, the chamber can be used in different X-ray diffraction scanning modes, namely, {theta}-2{theta} scanning, fixed {alpha}-2{theta} scanning, and also low angle techniques such as grazing incidence small angle X-ray scattering and X-ray reflectivity. The chamber was mounted on a standard four-circle diffractometer located in a synchrotron beam line and first used for a preliminary X-ray diffraction analysis of AlN thin films during their growth on the surface of a (100) silicon wafer.

  19. K alpha line emission during solar X-ray bursts

    NASA Technical Reports Server (NTRS)

    Phillips, K. J. H.; Neupert, W. M.

    1973-01-01

    Calculations of K alpha line emission from S, Ar, Ca and Fe are presented. It is reported that on the basis of data for hard X-ray bursts, the flux during most impulsive, non-thermal events is likely to be weak, though for a few strong bursts, a flux of approximately 100 photons/cm/s may be expected. The amount of S K alpha emission particularly is sensitively dependent on the value of the lower energy bound of the non-thermal electron distribution, offering a possible means of determining this. Thermal K alpha emission is only significant for Fe ions. The calculated thermal K alpha radiation is much less than that observed during an intense soft X-ray burst. It is concluded that a detailed temperature structure for the emission source is required in order to explain the discrepancy.

  20. Multiple powder diffraction data for an accurate charge density study using synchrotron radiation x-ray

    NASA Astrophysics Data System (ADS)

    Kasai, Hidetaka; Nishibori, Eiji

    2016-04-01

    In recent years multiple synchrotron radiation (SR) powder x-ray diffraction profiles have been successfully applied to advanced structural studies such as an accurate charge density study and a structure determination from powder diffraction. The results have been presented with several examples. Abilities and future prospects have been discussed using state of the art powder diffraction data.

  1. In-situ X-ray diffraction system using sources and detectors at fixed angular positions

    DOEpatents

    Gibson, David M.; Gibson, Walter M.; Huang, Huapeng

    2007-06-26

    An x-ray diffraction technique for measuring a known characteristic of a sample of a material in an in-situ state. The technique includes using an x-ray source for emitting substantially divergent x-ray radiation--with a collimating optic disposed with respect to the fixed source for producing a substantially parallel beam of x-ray radiation by receiving and redirecting the divergent paths of the divergent x-ray radiation. A first x-ray detector collects radiation diffracted from the sample; wherein the source and detector are fixed, during operation thereof, in position relative to each other and in at least one dimension relative to the sample according to a-priori knowledge about the known characteristic of the sample. A second x-ray detector may be fixed relative to the first x-ray detector according to the a-priori knowledge about the known characteristic of the sample, especially in a phase monitoring embodiment of the present invention.

  2. Pressure-induced structural distortion of TbMnO3 : A combined x-ray diffraction and x-ray absorption spectroscopy study

    NASA Astrophysics Data System (ADS)

    Chen, J. M.; Chou, T. L.; Lee, J. M.; Chen, S. A.; Chan, T. S.; Chen, T. H.; Lu, K. T.; Chuang, W. T.; Sheu, H.-S.; Chen, S. W.; Lin, C. M.; Hiraoka, N.; Ishii, H.; Tsuei, K. D.; Yang, T. J.

    2009-04-01

    The variation of electronic states and structural distortion in highly compressed multiferroic TbMnO3 was probed by x-ray diffraction (XRD) and x-ray absorption spectroscopy (XAS) using synchrotron radiation. Refined XRD data enabled observation of a reduced local Jahn-Teller (JT) distortion of Mn sites within MnO6 octahedra in TbMnO3 with increasing hydrostatic pressure. A progressively increasing intensity of the white line in MnK -edge x-ray absorption spectra of TbMnO3 was detected with increasing pressure. The absorption threshold of MnK -edge spectra of TbMnO3 is shifted toward higher energy, whereas the pre-edge peak is slightly shifted to lower energy with increasing hydrostatic pressure. We provide spectral evidence for pressure-induced bandwidth broadening for mangnites. The enhanced intensity of the white line and the shifted absorption threshold of MnK -edge spectra are explained in terms of a reduced JT distortion of MnO6 octahedra in compressed TbMnO3 . Comparison of XAS data with full-multiple-scattering calculations using code FDMNES shows satisfactory agreement between experimental and calculated MnK -edge spectra.

  3. High-resolution ab initio Three-dimensional X-ray Diffraction Microscopy

    SciTech Connect

    Chapman, H N; Barty, A; Marchesini, S; Noy, A; Cui, C; Howells, M R; Rosen, R; He, H; Spence, J H; Weierstall, U; Beetz, T; Jacobsen, C; Shapiro, D

    2005-08-19

    Coherent X-ray diffraction microscopy is a method of imaging non-periodic isolated objects at resolutions only limited, in principle, by the largest scattering angles recorded. We demonstrate X-ray diffraction imaging with high resolution in all three dimensions, as determined by a quantitative analysis of the reconstructed volume images. These images are retrieved from the 3D diffraction data using no a priori knowledge about the shape or composition of the object, which has never before been demonstrated on a non-periodic object. We also construct 2D images of thick objects with infinite depth of focus (without loss of transverse spatial resolution). These methods can be used to image biological and materials science samples at high resolution using X-ray undulator radiation, and establishes the techniques to be used in atomic-resolution ultrafast imaging at X-ray free-electron laser sources.

  4. High-resolution ab initio three-dimensional x-ray diffraction microscopy

    SciTech Connect

    Chapman, Henry N.; Barty, Anton; Marchesini, Stefano; Noy, Aleksandr; Hau-Riege, Stefan P.; Cui, Congwu; Howells, Malcolm R.; Rosen, Rachel; He, Haifeng; Spence, John C. H.; Weierstall, Uwe; Beetz, Tobias; Jacobsen, Chris; Shapiro, David

    2006-01-01

    Coherent x-ray diffraction microscopy is a method of imaging nonperiodic isolated objects at resolutions limited, in principle, by only the wavelength and largest scattering angles recorded. We demonstrate x-ray diffraction imaging with high resolution in all three dimensions, as determined by a quantitative analysis of the reconstructed volume images. These images are retrieved from the three-dimensional diffraction data using no a priori knowledge about the shape or composition of the object, which has never before been demonstrated on a nonperiodic object. We also construct two-dimensional images of thick objects with greatly increased depth of focus (without loss of transverse spatial resolution). These methods can be used to image biological and materials science samples at high resolution with x-ray undulator radiation and establishes the techniques to be used in atomic-resolution ultrafast imaging at x-ray free-electron laser sources.

  5. High-resolution x-ray diffraction microscopy of specifically labeled yeast cells

    DOE PAGESBeta

    Nelson, Johanna; Huang, Xiaojing; Steinbrener, Jan; Shapiro, David; Kirz, Janos; Marchesini, Stephano; Neiman, Aaron M.; Turner, Joshua J.; Jacobsen, Chris

    2010-04-20

    X-ray diffraction microscopy complements other x-ray microscopy methods by being free of lens-imposed radiation dose and resolution limits, and it allows for high-resolution imaging of biological specimens too thick to be viewed by electron microscopy. We report here the highest resolution (11-13 nm) x-ray diffraction micrograph of biological specimens, and a demonstration of molecular-specific gold labeling at different depths within cells via through-focus propagation of the reconstructed wavefield. The lectin concanavalin A conjugated to colloidal gold particles was used to label the α-mannan sugar in the cell wall of the yeast Saccharomyces cerevisiae. Cells were plunge-frozen in liquid ethane andmore » freeze-dried, after which they were imaged whole using x-ray diffraction microscopy at 750 eV photon energy.« less

  6. High-resolution ab initio three-dimensional x-ray diffraction microscopy

    DOE PAGESBeta

    Chapman, Henry N.; Barty, Anton; Marchesini, Stefano; Noy, Aleksandr; Hau-Riege, Stefan P.; Cui, Congwu; Howells, Malcolm R.; Rosen, Rachel; He, Haifeng; Spence, John C. H.; et al

    2006-01-01

    Coherent x-ray diffraction microscopy is a method of imaging nonperiodic isolated objects at resolutions limited, in principle, by only the wavelength and largest scattering angles recorded. We demonstrate x-ray diffraction imaging with high resolution in all three dimensions, as determined by a quantitative analysis of the reconstructed volume images. These images are retrieved from the three-dimensional diffraction data using no a priori knowledge about the shape or composition of the object, which has never before been demonstrated on a nonperiodic object. We also construct two-dimensional images of thick objects with greatly increased depth of focus (without loss of transverse spatialmore » resolution). These methods can be used to image biological and materials science samples at high resolution with x-ray undulator radiation and establishes the techniques to be used in atomic-resolution ultrafast imaging at x-ray free-electron laser sources.« less

  7. High-resolution x-ray diffraction microscopy of specifically labeled yeast cells

    SciTech Connect

    Nelson, Johanna; Huang, Xiaojing; Steinbrener, Jan; Shapiro, David; Kirz, Janos; Marchesini, Stephano; Neiman, Aaron M.; Turner, Joshua J.; Jacobsen, Chris

    2010-04-20

    X-ray diffraction microscopy complements other x-ray microscopy methods by being free of lens-imposed radiation dose and resolution limits, and it allows for high-resolution imaging of biological specimens too thick to be viewed by electron microscopy. We report here the highest resolution (11-13 nm) x-ray diffraction micrograph of biological specimens, and a demonstration of molecular-specific gold labeling at different depths within cells via through-focus propagation of the reconstructed wavefield. The lectin concanavalin A conjugated to colloidal gold particles was used to label the α-mannan sugar in the cell wall of the yeast Saccharomyces cerevisiae. Cells were plunge-frozen in liquid ethane and freeze-dried, after which they were imaged whole using x-ray diffraction microscopy at 750 eV photon energy.

  8. Phase Sensitive X-Ray Diffraction Imaging Study of Protein Crystals

    NASA Technical Reports Server (NTRS)

    Hu, Z. W.

    2003-01-01

    The study of defects and growth of protein crystals is of importance in providing a fundamental understanding of this important category of systems and the rationale for crystallization of better ordered crystals for structural determination and drug design. Yet, as a result of the extremely weak scattering power of x-rays in protein and other biological macromolecular crystals, the extinction lengths for those crystals are extremely large and, roughly speaking, of the order of millimeters on average compared to the scale of micrometers for most small molecular crystals. This has significant implication for x-ray diffraction and imaging study of protein crystals, and presents an interesting challenge to currently available x-ray analytical techniques. We proposed that coherence-based phase sensitive x-ray diffraction imaging could provide a way to augment defect contrast in x-ray diffraction images of weakly diffracting biological macromolecular crystals. I shall examine the principles and ideas behind this approach and compare it to other available x-ray topography and diffraction methods. I shall then present some recent experimental results in two model protein systems-cubic apofemtin and tetragonal lysozyme crystals to demonstrate the capability of the coherence-based imaging method in mapping point defects, dislocations, and the degree of perfection of biological macromolecular crystals with extreme sensitivity. While further work is under way, it is intended to show that the observed new features have yielded important information on protein crystal perfection and nucleation and growth mechanism otherwise unobtainable.

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

    PubMed

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

    2016-01-01

    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. PMID:27324109

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

    PubMed Central

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

    2016-01-01

    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. PMID:27324109

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

    SciTech Connect

    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.

  12. Advanced x-ray stress analysis method for a single crystal using different diffraction plane families

    SciTech Connect

    Imafuku, Muneyuki; Suzuki, Hiroshi; Sueyoshi, Kazuyuki; Akita, Koichi; Ohya, Shin-ichi

    2008-06-09

    Generalized formula of the x-ray stress analysis for a single crystal with unknown stress-free lattice parameter was proposed. This method enables us to evaluate the plane stress states with any combination of diffraction planes. We can choose and combine the appropriate x-ray sources and diffraction plane families, depending on the sample orientation and the apparatus, whenever diffraction condition is satisfied. The analysis of plane stress distributions in an iron single crystal was demonstrated combining with the diffraction data for Fe{l_brace}211{r_brace} and Fe{l_brace}310{r_brace} plane families.

  13. High temperature x-ray diffraction in transmission under controlled environment

    SciTech Connect

    Margulies, L.; Kramer, M.J.; Williams, J.J.; Deters, E.M.; McCallum, R.W.; Goldman, A.I.; Haeffner, D.R.; Lang, J.C.; Kycia, S.

    1998-12-31

    A compact tube furnace has been developed for high temperature X-ray diffraction studies using high energy synchrotron radiation. The furnace design has a low absorption path in transmission yet allows for a high degree of control of the sample atmosphere and a minimal temperature gradient across the sample. The design allows for a maximum temperature of 1,500 C with a variety of atmospheres including inert, reducing, and oxidizing. Preliminary results obtained at the SRI-CAT 1-ID undulator line (60 keV) at the APS facility and the A2 24 pole wiggler line (45 keV) at CHESS on the Ti{sub 5}Si{sub 3}Z{sub .5} (Z = C, N, O) system will be presented to demonstrate the feasibility of this approach.

  14. Femtosecond X-ray Diffraction From Two-Dimensional Protein Crystals

    SciTech Connect

    Frank, Matthias; Carlson, David B.; Hunter, Mark; Williams, Garth J.; Messerschmidt, Marc; Zatsepin, Nadia A.; Barty, Anton; Benner, Henry; Chu, Kaiqin; Graf, Alexander; Hau-Riege, Stefan; Kirian, Rick; Padeste, Celestino; Pardini, Tommaso; Pedrini, Bill; Segelke, Brent; Seibert, M. M.; Spence, John C.; Tsai, Ching-Ju; Lane, Steve M.; Li, Xiao-Dan; Schertler, Gebhard; Boutet, Sebastien; Coleman, Matthew A.; Evans, James E.

    2014-02-28

    Here we present femtosecond x-ray diffraction patterns from two-dimensional (2-D) protein crystals using an x-ray free electron laser (XFEL). To date it has not been possible to acquire x-ray diffraction from individual 2-D protein crystals due to radiation damage. However, the intense and ultrafast pulses generated by an XFEL permits a new method of collecting diffraction data before the sample is destroyed. Utilizing a diffract-before-destroy methodology at the Linac Coherent Light Source, we observed Bragg diffraction to better than 8.5 Å resolution for two different 2-D protein crystal samples that were 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.

  15. Closing the gap to the diffraction limit: Near wavelength limited tabletop soft x-ray coherent diffractive imaging

    NASA Astrophysics Data System (ADS)

    Sandberg, Richard Lunt

    Light microscopy has greatly advanced our understanding of nature. The achievable resolution, however, is limited by optical wavelengths to around 200 nm. Using novel imaging and labeling technologies, resolutions beyond the diffraction limit can be achieved for specialized specimens using techniques such as near-field scanning optical microscopy, stimulated emission depletion microscopy and structured illumination microscopy [1--3]. This dissertation presents a versatile soft x-ray diffraction microscope with 50 nm resolution using tabletop coherent soft x-ray sources. This work represents the first high resolution demonstrations of coherent diffractive or lensless imaging using tabletop extreme ultraviolet and soft x-ray sources [4, 5]. This dissertation also presents the first use of field curvature correction in x-ray coherent imaging which allows high numerical aperture imaging and near-diffraction-limited resolution of 1.5lambda. The relevant theory behind high harmonic generation, the primary tabletop source used in this work, will be discussed as well as the theory behind coherent diffractive imaging. Additionally, the first demonstration of tabletop soft x-ray Fourier Transform holography is shown with important applications to shorter wavelength imaging with high harmonic generation with limited flux. A tabletop soft x-ray diffraction microscope should find broad applications in biology, nanoscience, and materials science due to its simple optical design, high resolution, large depth of field, 3D imaging capability, scalability to shorter wavelengths, and ultrafast temporal resolution.

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

    NASA Astrophysics Data System (ADS)

    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.

  17. Measurement of coronal X-ray emission lines from Capella

    NASA Technical Reports Server (NTRS)

    Vedder, P. W.; Canizares, C. R.

    1983-01-01

    The Einstein Observatory's Focal Plane Crystal Spectrometer has detected X-ray emission lines due to O VIII, Fe XVII, and Fe XX, from the binary star system Capella. Line luminosities are well fitted by an emitting plasma at a single temperature of 6.29 + or - 0.01 - 0.03 million K, and a volume emission measure of about 8.6 x 10 to the 52nd/cu cm, corresponding to the low temperature component previously observed. A high temperature component is undetectable, since the observed lines are not produced in plasma at temperatures above about 20 million K. Nearly isothermal plasma would be expected if many of the magnetically confined coronal loops have similar sizes and pressures, and a second population of longer loops would be required to account for the hotter component. An alternative interpretation of the observed X-ray line emission and upper limit is that the plasma contains a continuous distribution of emission measure versus temperature that rises sharply to 3 million K and then falls by nearly a decade to 16 million. An extrapolation of the loop sizes suggested by this alternative to hotter, longer loops may also account for the higher temperature emission.

  18. Characterization of a 20-nm hard x-ray focus by ptychographic coherent diffractive imaging

    NASA Astrophysics Data System (ADS)

    Vila-Comamala, Joan; Diaz, Ana; Guizar-Sicairos, Manuel; Gorelick, Sergey; Guzenko, Vitaliy A.; Karvinen, Petri; Kewish, Cameron M.; Färm, Elina; Ritala, Mikko; Mantion, Alexandre; Bunk, Oliver; Menzel, Andreas; David, Christian

    2011-09-01

    Recent advances in the fabrication of diffractive X-ray optics have boosted hard X-ray microscopy into spatial resolutions of 30 nm and below. Here, we demonstrate the fabrication of zone-doubled Fresnel zone plates for multi-keV photon energies (4-12 keV) with outermost zone widths down to 20 nm. However, the characterization of such elements is not straightforward using conventional methods such as knife edge scans on well-characterized test objects. To overcome this limitation, we have used ptychographic coherent diffractive imaging to characterize a 20 nm-wide X-ray focus produced by a zone-doubled Fresnel zone plate at a photon energy of 6.2 keV. An ordinary scanning transmission X-ray microscope was modified to acquire the ptychographic data from a strongly scattering test object. The ptychographic algorithms allowed for the reconstruction of the image of the test object as well as for the reconstruction of the focused hard X-ray beam waist, with high spatial resolution and dynamic range. This method yields a full description of the focusing performance of the Fresnel zone plate and we demonstrate the usefulness ptychographic coherent diffractive imaging for metrology and alignment of nanofocusing diffractive X-ray lenses.

  19. Real-time observation of coherent acoustic phonons generated by an acoustically mismatched optoacoustic transducer using x-ray diffraction

    SciTech Connect

    Persson, A. I. H.; Andreasson, B. P.; Enquist, H.; Jurgilaitis, A.; Larsson, J.

    2015-11-14

    The spectrum of laser-generated acoustic phonons in indium antimonide coated with a thin nickel film has been studied using time-resolved x-ray diffraction. Strain pulses that can be considered to be built up from coherent phonons were generated in the nickel film by absorption of short laser pulses. Acoustic reflections at the Ni–InSb interface leads to interference that strongly modifies the resulting phonon spectrum. The study was performed with high momentum transfer resolution together with high time resolution. This was achieved by using a third-generation synchrotron radiation source that provided a high-brightness beam and an ultrafast x-ray streak camera to obtain a temporal resolution of 10 ps. We also carried out simulations, using commercial finite element software packages and on-line dynamic diffraction tools. Using these tools, it is possible to calculate the time-resolved x-ray reflectivity from these complicated strain shapes. The acoustic pulses have a peak strain amplitude close to 1%, and we investigated the possibility to use this device as an x-ray switch. At a bright source optimized for hard x-ray generation, the low reflectivity may be an acceptable trade-off to obtain a pulse duration that is more than an order of magnitude shorter.

  20. Apparatus for use in examining the lattice of a semiconductor wafer by X-ray diffraction

    NASA Technical Reports Server (NTRS)

    Parker, D. L.; Porter, W. A. (Inventor)

    1978-01-01

    An improved apparatus for examining the crystal lattice of a semiconductor wafer utilizing X-ray diffraction techniques was presented. The apparatus is employed in a method which includes the step of recording the image of a wafer supported in a bent configuration conforming to a compound curve, produced through the use of a vacuum chuck provided for an X-ray camera. The entire surface thereof is illuminated simultaneously by a beam of incident X-rays which are projected from a distant point-source and satisfy conditions of the Bragg Law for all points on the surface of the water.

  1. Pulse requirements for x-ray diffraction imaging of single biological molecules

    SciTech Connect

    Hau-Riege, S; London, R; Huldt, G; Chapman, H

    2005-01-05

    It has been suggested that x-ray free electron lasers will enable single-particle diffraction imaging of biological molecules. In this paper we present a model to estimate the required pulse parameters based on a trade-off between minimizing image degradation due to damage and maximizing the image signal-to-noise ratio. We discuss several means to alleviate the photon requirements, and compare the requirements with existing or planned x-ray sources such as short-pulse x-ray free-electron lasers.

  2. Quality experimental and calculated powder x-ray diffraction

    SciTech Connect

    Sullenger, D.B.; Cantrell, J.S.; Beiter, T.A.; Tomlin, D.W.

    1996-08-01

    For several years, we have submitted quality powder XRD patterns to the International Centre for Diffraction Data for inclusion as reference standards in their Powder Diffraction File. The procedure followed is described; examples used are {beta}-UH{sub 3}, {alpha}- BaT{sub 2}, alpha-lithium disilicate ({alpha}-Li{sub 2}Si{sub 2}O{sub 5}), and 2,2`,4,4`,6,6`hexanitroazobenzene-III (HNAB-III).

  3. Quantitative determination of mineral composition by powder X-ray diffraction

    DOEpatents

    Pawloski, Gayle A.

    1986-01-01

    An external standard intensity ratio method is used for quantitatively determining mineralogic compositions of samples by x-ray diffraction. The method uses ratios of x-ray intensity peaks from a single run. Constants are previously determined for each mineral which is to be quantitatively measured. Ratios of the highest intensity peak of each mineral to be quantified in the sample and the highest intensity peak of a reference mineral contained in the sample are used to calculate sample composition.

  4. Quantitative determination of mineral composition by powder x-ray diffraction

    DOEpatents

    Pawloski, G.A.

    1984-08-10

    An external standard intensity ratio method is used for quantitatively determining mineralogic compositions of samples by x-ray diffraction. The method uses ratios of x-ray intensity peaks from a single run. Constants are previously determined for each mineral which is to be quantitatively measured. Ratios of the highest intensity peak of each mineral to be quantified in the sample and the highest intensity peak of a reference mineral contained in the sample are used to calculate sample composition.

  5. X-ray diffraction and EXAFS analysis of materials for lithium-based rechargeable batteries

    SciTech Connect

    Sharkov, M. D. Boiko, M. E.; Bobyl, A. V.; Ershenko, E. M.; Terukov, E. I.; Zubavichus, Y. V.

    2013-12-15

    Lithium iron phosphate LiFePO{sub 4} (triphylite) and lithium titanate Li{sub 4}Ti{sub 5}O{sub 12} are used as components of a number of active materials in modern rechargeable batteries. Samples of these materials are studied by X-ray diffraction and extended X-ray absorption fine structure (EXAFS) spectroscopy. Hypotheses about the phase composition of the analyzed samples are formulated.

  6. Materials identification using a small-scale pixellated x-ray diffraction system

    NASA Astrophysics Data System (ADS)

    O’Flynn, D.; Crews, C.; Drakos, I.; Christodoulou, C.; Wilson, M. D.; Veale, M. C.; Seller, P.; Speller, R. D.

    2016-05-01

    A transmission x-ray diffraction system has been developed using a pixellated, energy-resolving detector (HEXITEC) and a small-scale, mains operated x-ray source (Amptek Mini-X). HEXITEC enables diffraction to be measured without the requirement of incident spectrum filtration, or collimation of the scatter from the sample, preserving a large proportion of the useful signal compared with other diffraction techniques. Due to this efficiency, sufficient molecular information for material identification can be obtained within 5 s despite the relatively low x-ray source power. Diffraction data are presented from caffeine, hexamine, paracetamol, plastic explosives and narcotics. The capability to determine molecular information from aspirin tablets inside their packaging is demonstrated. Material selectivity and the potential for a sample classification model is shown with principal component analysis, through which each different material can be clearly resolved.

  7. X-ray diffraction on precipitates in Czochralski-grown silicon

    NASA Astrophysics Data System (ADS)

    Caha, O.; Meduňa, M.

    2009-12-01

    The results of a study of oxygen precipitates in Czochralski grown silicon are reported. High-resolution X-ray diffraction was used to measure reciprocal space maps on samples after various annealing treatment. The measurements were performed for several diffraction orders and systematic differences between reciprocal space maps around different diffractions were found. The diffuse X-ray scattering intensity was simulated, where the displacement field of precipitates was calculated using continuum elasticity theory. The simulations give correct asymptotic behavior and the interpretation of intermediate region between Huang and core scattering processes is found. The X-ray diffraction results are correlated to the infrared absorption spectroscopy measurement involving the interstitial oxygen concentration.

  8. Transient x-ray diffraction used to diagnose shock compressed Si crystals on the Nova laser

    SciTech Connect

    Kalantar, D.H.; Chandler, E.A.; Colvin, J.D.; Lee, R.; Remington, B.A.; Weber, S.V.; Wiley, L.G.; Hauer, A.; Wark, J.S.; Loveridge, A.; Failor, B.H.; Meyers, M.A.; Ravichandran, G.

    1999-01-01

    Transient x-ray diffraction is used to record time-resolved information about the shock compression of materials. This technique has been applied on Nova shock experiments driven using a hohlraum x-ray drive. Data were recorded from the shock release at the free surface of a Si crystal, as well as from Si at an embedded ablator/Si interface. Modeling has been done to simulate the diffraction data incorporating the strained crystal rocking curves and Bragg diffraction efficiencies. Examples of the data and post-processed simulations are presented. {copyright} {ital 1999 American Institute of Physics.}

  9. Phase sensitive x-ray diffraction imaging of defects in biological macromolecular crystals

    NASA Technical Reports Server (NTRS)

    Hu, Z. W.; Lai, B.; Chu, Y. S.; Cai, Z.; Mancini, D. C.; Thomas, B. R.; Chernov, A. A.

    2001-01-01

    Conventional x-ray diffraction topography is currently used to map defects in the bulk of protein crystals, but the lack of sufficient contrast is frequently a limiting factor. We experimentally demonstrate that this barrier can be circumvented using a method that combines phase sensitive and diffraction imaging principles. Details of defects revealed in tetragonal lysozyme and cubic ferritin crystals are presented and discussed. The approach enabling the detection of the phase changes of diffracted x rays should prove to be useful in the study of defect structures in a broad range of biological macromolecular crystals.

  10. Development of High Pressure Single Crystal X-Ray Diffraction Study at ESRF ID 30 Beamline

    SciTech Connect

    Dhaussy, A.C.; Mezouar, M.; Mentre, O.

    2004-05-12

    We report about the newly single crystal diffraction set-up development at ID30 beamline at the European Synchrotron Radiation Facility (ESRF). To illustrate the experimental performance of this set-up, we also present X-ray diffraction spectra recorded at high pressure (HP) using dedicated diamond anvil cell (DAC). Using this new setup, high quality synchrotron single crystal X-ray diffraction measurements of Pb2V3O9 have been performed at HP. We evidenced a reordering in the distorted system by resorbing the existing twin. The structure was partially solved by direct methods and refined by the use of the BRUKER suite of programs package.

  11. X-ray diffraction experiments on the Materials in Extreme Conditions (MEC) LCLS x-ray FEL beamline

    NASA Astrophysics Data System (ADS)

    Smith, Raymond; Fratanduono, Dayne; Wicks, June; Duffy, Tom; Lee, Hae Ja; Granados, Eduardo; Heimann, Philip; Gleason, Arianna; Bolme, Cynthia; Swift, Damian; Coppari, Federica; Eggert, Jon; Collins, Rip

    2015-06-01

    The experiments described here were conducted on the MEC beamline hutch at the SLAC Linac Coherent Light Source. A 10 ns 527 nm laser pulse was used to shock compress 60-100 μm thick NaCl and Graphite samples. LCLS x-rays (40 fs, 8 keV), scattered off the shocked sample, were recorded on several pixel array detectors positioned downstream. The diffracted x-ray pattern allows us to determine changes in crystal structure at Mbar pressures and over nanosecond timescales. In this talk we detail the experimental setup, the current capabilities of the MEC laser and the considerations for optimizing the target design. We will describe the wave interactions within the shock-compressed target and the use of a 1D hydrocode to describe the pressure, temperature and density conditions within the target assembly as a function of time and Lagrangian position. We present observations of the B1-B2 phase transition in NaCl and subsequent back transformation during release to ambient pressure, and compare these findings to gas gun and static data. We also present results from a preliminary study of the shock-induced graphite to diamond transformation.

  12. Monitoring model drug microencapsulation in PLGA scaffolds using X-ray powder diffraction

    PubMed Central

    Aina, Adeyinka; Gupta, Manish; Boukari, Yamina; Morris, Andrew; Billa, Nashiru; Doughty, Stephen

    2015-01-01

    The microencapsulation of three model drugs; metronidazole, paracetamol and sulphapyridine into Poly (dl-Lactide-Co-Glycolide) (PLGA) scaffolds were probed using X-ray Powder Diffraction (XRPD). Changes in the diffraction patterns of the PLGA scaffolds after encapsulation was suggestive of a chemical interaction between the pure drugs and the scaffolds and not a physical intermixture. PMID:27013917

  13. Study of titanate nanotubes by X-ray and electron diffraction and electron microscopy

    SciTech Connect

    Brunatova, Tereza; Popelkova, Daniela; Wan, Wei; Oleynikov, Peter; Danis, Stanislav; Zou, Xiaodong; Kuzel, Radomir

    2014-01-15

    The structure of titanate nanotubes (Ti-NTs) was studied by a combination of powder X-ray diffraction (PXRD), electron diffraction and high resolution transmission electron microscopy (HRTEM). Ti-NTs are prepared by hydrothermal treatment of TiO{sub 2} powder. The structure is identified by powder X-ray diffraction as the one based on the structure of H{sub 2}Ti{sub 2}O{sub 5}·H{sub 2}O phase. The same structure is obtained by projected potential from HRTEM through-focus image series. The structure is verified by simulated PXRD pattern with the aid of the Debye formula. The validity of the model is tested by computing Fourier transformation of a single nanotube which is proportional to measured electron diffraction intensities. A good agreement of this calculation with measured precession electron diffraction data is achieved. - Highlights: • Titanate nanotubes were prepared by hydrothermal method. • X-ray powder diffraction indicated their structure based on that of H{sub 2}Ti{sub 2}O{sub 5}·H{sub 2}O. • Structural model was created with the aid of high-resolution electron microscopy. • The model was verified with electron diffraction data. • X-ray powder diffraction pattern was calculated with the aid of the Debye formula.

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

    ERIC Educational Resources Information Center

    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…

  15. Ultra-high resolution zone-doubled diffractive X-ray optics for the multi-keV regime.

    PubMed

    Vila-Comamala, Joan; Gorelick, Sergey; Färm, Elina; Kewish, Cameron M; Diaz, Ana; Barrett, Ray; Guzenko, Vitaliy A; Ritala, Mikko; David, Christian

    2011-01-01

    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. PMID:21263555

  16. High pressure x-ray diffraction studies on nanocrystalline materials

    NASA Astrophysics Data System (ADS)

    Palosz, B.; Stel'makh, S.; Grzanka, E.; Gierlotka, S.; Pielaszek, R.; Bismayer, U.; Werner, S.; Palosz, W.

    2004-02-01

    Application of the in situ high pressure powder diffraction technique for examination of specific structural properties of nanocrystals based on the experimental data of SiC nanocrystalline powders of 2-30 nm in diameter is presented. Limitations and capabilities of the experimental techniques themselves and methods of diffraction data elaboration applied to nanocrystals with very small dimensions (<30 nm) are discussed. It is shown that a unique value of the lattice parameter cannot be determined for such small crystals using a standard powder diffraction experiment. It is also shown that, due to the complex structure constituting a two-phase, core/surface shell system, no unique compressibility coefficient can satisfactorily describe the behaviour of nanocrystalline powders under pressure. We offer a tentative interpretation of the distribution of macro- and micro-strains in nanoparticles of different grain size.

  17. High Pressure X-Ray Diffraction Studies of Nanocrystalline Materials

    NASA Technical Reports Server (NTRS)

    Palosz, B.; Stel'makh, S.; Grzanka, E.; Gierlotka, S.; Palosz, W.

    2004-01-01

    Experimental evidence obtained for a variety of nanocrystalline materials suggest that the crystallographic structure of a very small size particle deviates from that in the bulk crystals. In this paper we show the effect of the surface of nanocrystals on their structure by the analysis of generation and distribution of macro- and micro-strains at high pressures and their dependence on the grain size in nanocrystalline powders of Sic. We studied the structure of Sic nanocrystals by in-situ high-pressure powder diffraction technique using synchrotron and neutron sources and hydrostatic or isostatic pressure conditions. The diffraction measurements were done in HASYLAB at DESY using a Diamond Anvil Cell (DAC) in the energy dispersive geometry in the diffraction vector range up to 3.5 - 4/A and under pressures up to 50 GPa at room temperature. In-situ high pressure neutron diffraction measurements were done at LANSCE in Los Alamos National Laboratory using the HIPD and HIPPO diffractometers with the Paris-Edinburgh and TAP-98 cells, respectively, in the diffraction vector range up to 26 Examination of the response of the material to external stresses requires nonstandard methodology of the materials characterization and description. Although every diffraction pattern contains a complete information on macro- and micro-strains, a high pressure experiment can reveal only those factors which contribute to the characteristic diffraction patterns of the crystalline phases present in the sample. The elastic properties of powders with the grain size from several nm to micrometers were examined using three methodologies: (l), the analysis of positions and widths of individual Bragg reflections (used for calculating macro- and micro-strains generated during densification) [I], (2). the analysis of the dependence of the experimental apparent lattice parameter, alp, on the diffraction vector Q [2], and (3), the atomic Pair Distribution Function (PDF) technique [3]. The results

  18. X-Ray Diffraction Study on the Strain Anisotropy and Dislocation Structure of Deformed Lath Martensite

    NASA Astrophysics Data System (ADS)

    Hossein Nedjad, S.; Hosseini Nasab, F.; Movaghar Garabagh, M. R.; Damadi, S. R.; Nili Ahmadabadi, M.

    2011-08-01

    18Ni (300) maraging steel possessing lath martensite structure was deformed by four passes of equal-channel angular pressing (ECAP) at ambient temperature. Line profile analysis (LPA) of X-ray diffraction (XRD) patterns identified strong strain anisotropy and remarkable increases in the relative fraction of screw dislocations after ECAP. The strain anisotropy was reasonably accounted for by the anisotropy of elastic constants. Domination of screw dislocations in the deformed structure was attributed to the preferred annihilation of edge dislocations in the early stages of deformation along with the difficulties for annihilation of screw dislocations by cross slipping. Cobalt addition was mainly assumed to make cross slipping difficult by reducing stacking-fault energy and favoring short-range ordering.

  19. Synchrotron X-Ray Diffraction Studies of Olivine from Comet Wild 2

    NASA Technical Reports Server (NTRS)

    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).

  20. Combined X-ray and neutron fibre diffraction studies of biological and synthetic polymers.

    SciTech Connect

    Parrot, I. M.; Urban, Volker S; Gardner, K. H.; Forsyth, V. T.

    2005-04-01

    The fibrous state is a natural one for polymer molecules which tend to assume regular helical conformations rather than the globular structures characteristic of many proteins. Fibre diffraction therefore has broad application to the study of a wide range of biological and synthetic polymers. The purpose of this paper is to illustrate the general scope of the method and in particular to demonstrate the impact of a combined approach involving both X-ray and neutron diffraction methods. While the flux of modern X-ray synchrotron radiation sources allows high quality datasets to be recorded with good resolution within a very short space of time, neutron studies can provide unique information through the ability to locate hydrogen or deuterium atoms that are often difficult or impossible to locate using X-ray methods. Furthermore, neutron fibre diffraction methods can, through the ability to selectively label specific parts of a structure, be used to highlight novel aspects of polymer structure that can not be studied using X-rays. Two examples are given. The first describes X-ray and neutron diffraction studies of conformational transitions in DNA. The second describes structural studies of the synthetic high-performance polymer poly(p-phenylene terephthalamide) (PPTA), known commercially as Kevlar{reg_sign} or Twaron{reg_sign}.

  1. Coherent x-ray zoom condenser lens for diffractive and scanning microscopy.

    PubMed

    Kimura, Takashi; Matsuyama, Satoshi; Yamauchi, Kazuto; Nishino, Yoshinori

    2013-04-22

    We propose a coherent x-ray zoom condenser lens composed of two-stage deformable Kirkpatrick-Baez mirrors. The lens delivers coherent x-rays with a controllable beam size, from one micrometer to a few tens of nanometers, at a fixed focal position. The lens is suitable for diffractive and scanning microscopy. We also propose non-scanning coherent diffraction microscopy for extended objects by using an apodized focused beam produced by the lens with a spatial filter. The proposed apodized-illumination method will be useful in highly efficient imaging with ultimate storage ring sources, and will also open the way to single-shot coherent diffraction microscopy of extended objects with x-ray free-electron lasers. PMID:23609637

  2. Signal-to-noise and radiation exposure considerations in conventional and diffraction x-ray microscopy.

    PubMed

    Huang, Xiaojing; Miao, Huijie; Steinbrener, Jan; Nelson, Johanna; Shapiro, David; Stewart, Andrew; Turner, Joshua; Jacobsen, Chris

    2009-08-01

    Using a signal-to-noise ratio estimation based on correlations between multiple simulated images, we compare the dose efficiency of two soft x-ray imaging systems: incoherent brightfield imaging using zone plate optics in a transmission x-ray microscope (TXM), and x-ray diffraction microscopy (XDM) where an image is reconstructed from the far-field coherent diffraction pattern. In XDM one must computationally phase weak diffraction signals; in TXM one suffers signal losses due to the finite numerical aperture and efficiency of the optics. In simulations with objects representing isolated cells such as yeast, we find that XDM has the potential for delivering equivalent resolution images using fewer photons. This can be an important advantage for studying radiation-sensitive biological and soft matter specimens. PMID:19654762

  3. Scanning force microscope for in situ nanofocused X-ray diffraction studies

    PubMed Central

    Ren, Zhe; Mastropietro, Francesca; Davydok, Anton; Langlais, Simon; Richard, Marie-Ingrid; Furter, Jean-Jacques; Thomas, Olivier; Dupraz, Maxime; Verdier, Marc; Beutier, Guillaume; Boesecke, Peter; Cornelius, Thomas W.

    2014-01-01

    A compact scanning force microscope has been developed for in situ combination with nanofocused X-ray diffraction techniques at third-generation synchrotron beamlines. Its capabilities are demonstrated on Au nano-islands grown on a sapphire substrate. The new in situ device allows for in situ imaging the sample topography and the crystallinity by recording simultaneously an atomic force microscope (AFM) image and a scanning X-ray diffraction map of the same area. Moreover, a selected Au island can be mechanically deformed using the AFM tip while monitoring the deformation of the atomic lattice by nanofocused X-ray diffraction. This in situ approach gives access to the mechanical behavior of nanomaterials. PMID:25178002

  4. Imaging nanoscale lattice variations by machine learning of x-ray diffraction microscopy data.

    PubMed

    Laanait, Nouamane; Zhang, Zhan; Schlepütz, Christian M

    2016-09-16

    We present a novel methodology based on machine learning to extract lattice variations in crystalline materials, at the nanoscale, from an x-ray Bragg diffraction-based imaging technique. By employing a full-field microscopy setup, we capture real space images of materials, with imaging contrast determined solely by the x-ray diffracted signal. The data sets that emanate from this imaging technique are a hybrid of real space information (image spatial support) and reciprocal lattice space information (image contrast), and are intrinsically multidimensional (5D). By a judicious application of established unsupervised machine learning techniques and multivariate analysis to this multidimensional data cube, we show how to extract features that can be ascribed physical interpretations in terms of common structural distortions, such as lattice tilts and dislocation arrays. We demonstrate this 'big data' approach to x-ray diffraction microscopy by identifying structural defects present in an epitaxial ferroelectric thin-film of lead zirconate titanate. PMID:27505613

  5. Signal-to-noise and radiation exposure considerations in conventional and diffraction x-ray microscopy

    PubMed Central

    Huang, Xiaojing; Miao, Huijie; Steinbrener, Jan; Nelson, Johanna; Shapiro, David; Stewart, Andrew; Turner, Joshua; Jacobsen, Chris

    2010-01-01

    Using a signal-to-noise ratio estimation based on correlations between multiple simulated images, we compare the dose efficiency of two soft x-ray imaging systems: incoherent brightfield imaging using zone plate optics in a transmission x-ray microscope (TXM), and x-ray diffraction microscopy (XDM) where an image is reconstructed from the far-field coherent diffraction pattern. In XDM one must computationally phase weak diffraction signals; in TXM one suffers signal losses due to the finite numerical aperture and efficiency of the optics. In simulations with objects representing isolated cells such as yeast, we find that XDM has the potential for delivering equivalent resolution images using fewer photons. This can be an important advantage for studying radiation-sensitive biological and soft matter specimens. PMID:19654762

  6. Imaging nanoscale lattice variations by machine learning of x-ray diffraction microscopy data

    NASA Astrophysics Data System (ADS)

    Laanait, Nouamane; Zhang, Zhan; Schlepütz, Christian M.

    2016-09-01

    We present a novel methodology based on machine learning to extract lattice variations in crystalline materials, at the nanoscale, from an x-ray Bragg diffraction-based imaging technique. By employing a full-field microscopy setup, we capture real space images of materials, with imaging contrast determined solely by the x-ray diffracted signal. The data sets that emanate from this imaging technique are a hybrid of real space information (image spatial support) and reciprocal lattice space information (image contrast), and are intrinsically multidimensional (5D). By a judicious application of established unsupervised machine learning techniques and multivariate analysis to this multidimensional data cube, we show how to extract features that can be ascribed physical interpretations in terms of common structural distortions, such as lattice tilts and dislocation arrays. We demonstrate this ‘big data’ approach to x-ray diffraction microscopy by identifying structural defects present in an epitaxial ferroelectric thin-film of lead zirconate titanate.

  7. Signal-to-noise and radiation exposure considerations in conventional and diffraction x-ray microscopy

    DOE PAGESBeta

    Huang, Xiaojing; Miao, Huijie; Steinbrener, Jan; Nelson, Johanna; Shapiro, David; Stewart, Andrew; Turner, Joshua; Jacobsen, Chris

    2009-01-01

    Using a signal-to-noise ratio estimation based on correlations between multiple simulated images, we compare the dose efficiency of two soft x-ray imaging systems: incoherent brightfield imaging using zone plate optics in a transmission x-ray microscope (TXM), and x-ray diffraction microscopy (XDM) where an image is reconstructed from the far-field coherent diffraction pattern. In XDM one must computationally phase weak diffraction signals; in TXM one suffers signal losses due to the finite numerical aperture and efficiency of the optics. In simulations with objects representing isolated cells such as yeast, we find that XDM has the potential for delivering equivalent resolution imagesmore » using fewer photons. As a result, this can be an important advantage for studying radiation-sensitive biological and soft matter specimens.« less

  8. Signal-to-noise and radiation exposure considerations in conventional and diffraction x-ray microscopy

    SciTech Connect

    Huang, Xiaojing; Miao, Huijie; Steinbrener, Jan; Nelson, Johanna; Shapiro, David; Stewart, Andrew; Turner, Joshua; Jacobsen, Chris

    2009-01-01

    Using a signal-to-noise ratio estimation based on correlations between multiple simulated images, we compare the dose efficiency of two soft x-ray imaging systems: incoherent brightfield imaging using zone plate optics in a transmission x-ray microscope (TXM), and x-ray diffraction microscopy (XDM) where an image is reconstructed from the far-field coherent diffraction pattern. In XDM one must computationally phase weak diffraction signals; in TXM one suffers signal losses due to the finite numerical aperture and efficiency of the optics. In simulations with objects representing isolated cells such as yeast, we find that XDM has the potential for delivering equivalent resolution images using fewer photons. As a result, this can be an important advantage for studying radiation-sensitive biological and soft matter specimens.

  9. Note: Application of a pixel-array area detector to simultaneous single crystal x-ray diffraction and x-ray absorption spectroscopy measurements

    SciTech Connect

    Sun, Cheng-Jun Brewe, Dale L.; Heald, Steve M.; Zhang, Bangmin; Chen, Jing-Sheng; Chow, G. M.; Venkatesan, T.

    2014-04-15

    X-ray diffraction (XRD) and X-ray absorption spectroscopy (XAS) are two main x-ray techniques in synchrotron radiation facilities. In this Note, we present an experimental setup capable of performing simultaneous XRD and XAS measurements by the application of a pixel-array area detector. For XRD, the momentum transfer in specular diffraction was measured by scanning the X-ray energy with fixed incoming and outgoing x-ray angles. By selecting a small fixed region of the detector to collect the XRD signal, the rest of the area was available for collecting the x-ray fluorescence for XAS measurements. The simultaneous measurement of XRD and X-ray absorption near edge structure for Pr{sub 0.67}Sr{sub 0.33}MnO{sub 3} film was demonstrated as a proof of principle for future time-resolved pump-probe measurements. A static sample makes it easy to maintain an accurate overlap of the X-ray spot and laser pump beam.

  10. Observations of Shock-Loaded Tin and Zirconium Surfaces with Single-Pulse X-ray Diffraction

    SciTech Connect

    Dane V. Morgan, Mike Grover, Don Macy, Mike Madlener, Gerald Stevens, and William D. Turley

    2010-06-01

    A single-pulse X-ray diffraction (XRD) diagnostic has been developed for the investigation of shocked material properties on a very short time scale. The diagnostic, which consists of a 37-stage Marx bank high-voltage pulse generator coupled to a needle-and-washer electron beam diode via coaxial cable, produces line-and-bremsstrahlung X-ray emission in a 40 ns pulse. The molybdenum anode produces 0.71 Å characteristic K lines used for diffraction. The X-ray beam passes through a pinhole collimator and is incident on the sample with an approximately 2 mm×5 mm spot and 1° full width at half maximum angular divergence. Coherent scattering from the sample produces a Debye-Scherrer diffraction pattern on an image plate located at 75 mm from the polycrystalline sample surface. An experimental study of the polycrystalline structures of zirconium and tin under high-pressure shock loading has been conducted with single-pulse XRD. The experimental targets were 0.1-mm-thick foils of zirconium and tin using 0.4-mm-thick vitreous carbon back windows for shock loading, and the shocks were produced by either Detasheet or PBX-9501 high explosives buffered by 1-mm-thick 6061-T6 aluminum. The diffraction patterns from both shocked zirconium and tin indicated a phase transition into a polymorphic mix of amorphous and new solid phases.

  11. Image restoration of line-scanned x-ray images

    NASA Astrophysics Data System (ADS)

    Haff, Ron P.; Schatzki, Thomas F.

    1997-12-01

    Six specific defects in images captured on line-scan x-ray machines are discussed and software corrections are addressed. The corrections are intended to optimize the machine for the inspection of food products for hidden defects or contaminants. The defects include effects due to time constants in the preamplifier, decays (short and long term) of the phosphor in the detectors, gaps in the images at detector module boundaries, analog to digital converter clipping of the photodiode signal, varying response between detectors to the low-energy end of the incident energy spectrum, and x-ray scattering. Of these, all but the long-term phosphor decay and scattering are corrected with software. While the long-term phosphor decay is of little consequence for food inspection, effects due to scattering are serious and must be addressed in the design of the detectors. The restored image is more suitable for image processing and thus for real-time sorting than the original image.

  12. X-Ray Weak Broad-Line Quasars: Absorption or Intrinsic X-Ray Weakness

    NASA Technical Reports Server (NTRS)

    Risaliti, Guido; Mushotzky, Richard F. (Technical Monitor)

    2004-01-01

    XMM observations of X-ray weak quasars have been performed during 2003. The data for all but the last observation are now available (there has been a delay of several months on the initial schedule, due to high background flares which contaminated the observations: as a consequence, most of them had to be rescheduled). We have reduced and analyzed these data, and obtained interesting preliminary scientific results. Out of the eight sources, 4 are confirmed to be extrimely X-ray weak, in agreement with the results of previous Chandra observations. 3 sources are confirmed to be highly variable both in flux (by factors 20-50) and in spectral properties (dramatic changes in spectral index). For both these groups of objects, an article is in preparation. Preliminary results have been presented at an international workshop on AGN surveys in December 2003, in Cozumel (Mexico). In order to further understand the nature of these X-ray weak quasars, we submitted proposals for spectroscopy at optical and infrared telescopes. We obtained time at the TNG 4 meter telescope for near-IR observations, and at the Hobby-Eberly Telescope for optical high-resolution spectroscopy. These observations will be performed in early 2004, and will complement the XMM data, in order to understand whether the X-ray weakness of these sources is an intrinsic property or is due to absorption by circumnuclear material.

  13. High resolution double-sided diffractive optics for hard X-ray microscopy.

    PubMed

    Mohacsi, Istvan; Vartiainen, Ismo; Guizar-Sicairos, Manuel; Karvinen, Petri; Guzenko, Vitaliy A; Müller, Elisabeth; Färm, Elina; Ritala, Mikko; Kewish, Cameron M; Somogyi, Andrea; David, Christian

    2015-01-26

    The fabrication of high aspect ratio metallic nanostructures is crucial for the production of efficient diffractive X-ray optics in the hard X-ray range. We present a novel method to increase their structure height via the double-sided patterning of the support membrane. In transmission, the two Fresnel zone plates on the two sides of the substrate will act as a single zone plate with added structure height. The presented double-sided zone plates with 30 nm smallest zone width offer up to 9.9% focusing efficiency at 9 keV, that results in a factor of two improvement over their previously demonstrated single-sided counterparts. The increase in efficiency paves the way to speed up X-ray microscopy measurements and allows the more efficient utilization of the flux in full-field X-ray microscopy. PMID:25835837

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

    NASA Astrophysics Data System (ADS)

    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.

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

    SciTech Connect

    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.

  16. Application of the Debye formula to the computation of x-ray diffraction patterns of nanostructured diffusion couples

    NASA Astrophysics Data System (ADS)

    Cheung, Charles; Kelly, Brian; Unruh, Karl; Decamp, Matthew

    Time resolved optical pump/x-ray probe techniques have made it possible to acquire x-ray diffraction patterns corresponding to very early diffusion times in nanostructured diffusion couples. The analysis of these diffraction patterns, however, is complicated by significant line broadening and other finite size effects that appear in samples containing a relatively small number of scatterers. In order to better quantify these issues, x-ray diffraction patterns have been calculated by the direct application of the Debye formula to core/shell and thin film diffusion couples. In particular a series of diffraction patterns have been calculated as a function of the sample size and composition profile determined from the appropriate solutions to Fick's second law. The results of these calculations have been used to guide the interpretation of the measured diffraction patterns of Pt/Ni core/shell nanoparticles and Pt/Ni thin film multilayers. This material is based upon work supported by the National Science Foundation under Grant No. 1410076.

  17. An X-ray diffractometer using mirage diffraction

    PubMed Central

    Fukamachi, Tomoe; Jongsukswat, Sukswat; Ju, Dongying; Negishi, Riichirou; Hirano, Keiichi; Kawamura, Takaaki

    2014-01-01

    Some characteristics are reported of a triple-crystal diffractometer with a (+, −, +) setting of Si(220) using mirage diffraction. The first crystal is flat, while the second and third crystals are bent. Basically, the first crystal is used as a collimator, the second as a monochromator and the third as the sample. The third crystal also works as an analyzer. The advantages of this diffractometer are that its setup is easy, its structure is simple, the divergence angle from the second crystal is small and the energy resolution of the third crystal is high, of the order of sub-meV. PMID:25242911

  18. Diffraction crystal for sagittally focusing x-rays

    DOEpatents

    Ice, Gene E.; Sparks, Jr., Cullie J.

    1984-01-01

    The invention is a new type of diffraction crystal designed for sagittally focusing photons of various energies. The invention is based on the discovery that such focusing is not obtainable with conventional crystals because of distortion resulting from anticlastic curvature. The new crystal comprises a monocrystalline base having a front face contoured for sagittally focusing photons and a back face provided with rigid, upstanding, stiffening ribs restricting anticlastic curvature. When mounted in a suitable bending device, the reflecting face of the crystal can be adjusted to focus photons having any one of a range of energies.

  19. An X-ray diffractometer using mirage diffraction.

    PubMed

    Fukamachi, Tomoe; Jongsukswat, Sukswat; Ju, Dongying; Negishi, Riichirou; Hirano, Keiichi; Kawamura, Takaaki

    2014-08-01

    Some characteristics are reported of a triple-crystal diffractometer with a (+, -, +) setting of Si(220) using mirage diffraction. The first crystal is flat, while the second and third crystals are bent. Basically, the first crystal is used as a collimator, the second as a monochromator and the third as the sample. The third crystal also works as an analyzer. The advantages of this diffractometer are that its setup is easy, its structure is simple, the divergence angle from the second crystal is small and the energy resolution of the third crystal is high, of the order of sub-meV. PMID:25242911

  20. Diffraction crystals for sagittally focusing x-rays

    DOEpatents

    Ice, G.E.; Sparks, C.J. Jr.

    1982-06-07

    The invention is a new type of diffraction crystal designed for sagittally focusing photons of various energies. The invention is based on the discovery that such focusing is not obtainable with conventional crystals because of distortion resulting from anticlastic curvature. The new crystal comprises a monocrystalline base having a front face contoured for sagittally focusing photons and a back face provided with rigid, upstanding, stiffening ribs restricting anticlastic curvature. When mounted in a suitable bending device, the reflecting face of the crystal can be adjusted to focus photons having any one of a range of energies.

  1. A method for automated determination of the crystal structures from X-ray powder diffraction data

    SciTech Connect

    Hofmann, D. W. M. Kuleshova, L. N.

    2006-05-15

    An algorithm is proposed for determining the crystal structure of compounds. In the framework of this algorithm, X-ray powder diffraction patterns are compared using a new similarity index. Unlike the indices traditionally employed in X-ray powder diffraction analysis, the new similarity index can be applied even in the case of overlapping peaks and large differences in unit cell parameters. The capabilities of the proposed procedure are demonstrated by solving the crystal structures of a number of organic pigments (PY111, PR181, Me-PR170)

  2. A framework for 3-D coherent diffraction imaging by focused beam x-ray Bragg ptychography.

    SciTech Connect

    Hruszkewycz, S. O.; Holt, M. V.; Tripathi, A.; Maser, J.; Fuoss, P. H.

    2011-06-15

    We present the framework for convergent beam Bragg ptychography, and, using simulations, we demonstrate that nanocrystals can be ptychographically reconstructed from highly convergent x-ray Bragg diffraction. The ptychographic iterative engine is extended to three dimensions and shown to successfully reconstruct a simulated nanocrystal using overlapping raster scans with a defocused curved beam, the diameter of which matches the crystal size. This object reconstruction strategy can serve as the basis for coherent diffraction imaging experiments at coherent scanning nanoprobe x-ray sources.

  3. Crystallization and preliminary X-ray diffraction study of porcine carboxypeptidase B

    SciTech Connect

    Akparov, V. Kh.; Timofeev, V. I. Kuranova, I. P.

    2015-05-15

    Crystals of porcine pancreatic carboxypeptidase B have been grown in microgravity by the capillary counter-diffusion method through a gel layer. The X-ray diffraction study showed that the crystals belong to sp. gr. P4{sub 1}2{sub 1}2 and have the following unit-cell parameters: a = b = 79.58 Å, c = 100.51 Å; α = β = γ = 90.00°. The X-ray diffraction data set suitable for the determination of the three-dimensional structure at atomic resolution was collected from one of the grown crystals at the SPring 8 synchrotron facility to 0.98 Å resolution.

  4. Nanoscale Imaging of Mineral Crystals inside Biological Composite Materials Using X-Ray Diffraction Microscopy

    NASA Astrophysics Data System (ADS)

    Jiang, Huaidong; Ramunno-Johnson, Damien; Song, Changyong; Amirbekian, Bagrat; Kohmura, Yoshiki; Nishino, Yoshinori; Takahashi, Yukio; Ishikawa, Tetsuya; Miao, Jianwei

    2008-01-01

    We for the first time applied x-ray diffraction microscopy to the imaging of mineral crystals inside biological composite materials—intramuscular fish bone—at the nanometer scale resolution. We identified mineral crystals in collagen fibrils at different stages of mineralization. Based on the experimental results and biomineralization analyses, we suggested a dynamic model to account for the nucleation and growth of mineral crystals in the collagen matrix. The results obtained from this study not only further our understanding of the complex structure of bone, but also demonstrate that x-ray diffraction microscopy will become an important tool to study biological materials.

  5. Elastic properties of supported polycrystalline thin films and multilayers: An X-ray diffraction study

    SciTech Connect

    Goudeau, P.; Villain, P.; Tamura, N.; Renault, P.-O.; Badawi, K.F.; Padmore, H.A.

    2003-08-13

    Numerous experimental and theoretical studies have shown that thin film elastic behavior may be different from the bulk one due to size effects related to grain boundaries, free surfaces and interfaces. In addition, thin films often present high compressive residual stresses which may be responsible of thin film buckling. These two features will be discussed in this communication through recent x-ray diffraction experiments: in situ tensile testing for elastic constant analysis and scanning x-ray micro diffraction for stress relaxation measurements associated with film buckling.

  6. Bone structure studies with HNDT and x-ray diffraction methods

    NASA Astrophysics Data System (ADS)

    Silvennoinen, Raimo V. J.; Nygren, Kaarlo; Rouvinen, Juha; Petrova, Valentina V.

    1993-09-01

    Changes in molecular texture and structure of isolated radioulnar bones of subadult European moose collected in various environmental pollution areas of Finland were investigated by using HNDT and x-ray diffraction methods. By using small caudo-cranial bending forces, the bones were tested by using HNDT. For bone molecular texture and structure studies by using x-ray diffraction methods, samples were taken from the ulnar metaphyse (Olecranon). Results show that the bones obtained from the Harjavalta area and one from North Karelia showed changes in molecular texture and structure compared with samples from apparently normal animals.

  7. Simulating Picosecond X-ray Diffraction from shocked crystals by Post-processing Molecular Dynamics Calculations

    SciTech Connect

    Kimminau, G; Nagler, B; Higginbotham, A; Murphy, W; Park, N; Hawreliak, J; Kadau, K; Germann, T C; Bringa, E M; Kalantar, D; Lorenzana, H; Remington, B; Wark, J

    2008-06-19

    Calculations of the x-ray diffraction patterns from shocked crystals derived from the results of Non-Equilibrium-Molecular-Dynamics (NEMD) simulations are presented. The atomic coordinates predicted by the NEMD simulations combined with atomic form factors are used to generate a discrete distribution of electron density. A Fast-Fourier-Transform (FFT) of this distribution provides an image of the crystal in reciprocal space, which can be further processed to produce quantitative simulated data for direct comparison with experiments that employ picosecond x-ray diffraction from laser-irradiated crystalline targets.

  8. Mapping of residual strains of a ceramic-to-metal joint using X-ray diffraction

    SciTech Connect

    Watkins, T.R.; Wang, X.L.; Spooner, S.; Hubbard, C.R.; Vance, S.J.; Rabin, B.H.; Williamson, R.L.

    1994-03-01

    In this study, the residual strains in the iron layer of a zirconia-iron joint, brazed with a metal alloy, were measured with X-ray diffraction as a function of distance from the joint. The residual strains were measured at various key locations indicated by a finite element model (FEM). The X-ray residual strain mapping results were compared to neutron diffraction mapping results. These data were combined to provide a complete residual strain profile of these samples and were compared with results of FEM.

  9. Characterization of an Yb:LuVO 4 single crystal using X-ray topography, high-resolution X-ray diffraction, and X-ray photoelectron spectroscopy

    NASA Astrophysics Data System (ADS)

    Paszkowicz, W.; Romanowski, P.; Bąk-Misiuk, J.; Wierzchowski, W.; Wieteska, K.; Graeff, W.; Iwanowski, R. J.; Heinonen, M. H.; Ermakova, O.; Dąbkowska, H.

    2011-10-01

    Knowledge on the defect and electronic structure allows for improved modeling of material properties. A short literature review has shown that the information on defect structure of rare earth orthovanadate single crystals is limited. In this paper, defect and electronic structure of a needle-shaped Yb:LuVO 4 single crystal grown by the slow cooling method have been studied by means of X-ray diffraction topography employing white synchrotron beam, high-resolution diffraction (HRD) and photoelectron spectroscopy (XPS) techniques. Topographic investigations show that the crystal is composed of two blocks disoriented by about 1.5° and separated by a narrow deformed region. Some contrasts observed within the crystal volume may be attributed to glide bands and sector boundaries. The contrasts appearing in the vicinity of the surface may be interpreted as due to the presence of small inclusions. The HRD study indicates, in particular, that among point defects, the vacancy type defects dominate and that the density of other defects is small in comparison. The XPS measurements enabled, despite highly insulating properties of the studied crystal, an analysis of its bulk electronic structure, including the main core-levels (O 1 s, V 2 p, Lu 4 f) as well as the valence band range.

  10. Real-time direct and diffraction X-ray imaging of irregular silicon wafer breakage

    PubMed Central

    Rack, Alexander; Scheel, Mario; Danilewsky, Andreas N.

    2016-01-01

    Fracture and breakage of single crystals, particularly of silicon wafers, are multi-scale problems: the crack tip starts propagating on an atomic scale with the breaking of chemical bonds, forms crack fronts through the crystal on the micrometre scale and ends macroscopically in catastrophic wafer shattering. Total wafer breakage is a severe problem for the semiconductor industry, not only during handling but also during temperature treatments, leading to million-dollar costs per annum in a device production line. Knowledge of the relevant dynamics governing perfect cleavage along the {111} or {110} faces, and of the deflection into higher indexed {hkl} faces of higher energy, is scarce due to the high velocity of the process. Imaging techniques are commonly limited to depicting only the state of a wafer before the crack and in the final state. This paper presents, for the first time, in situ high-speed crack propagation under thermal stress, imaged simultaneously in direct transmission and diffraction X-ray imaging. It shows how the propagating crack tip and the related strain field can be tracked in the phase-contrast and diffracted images, respectively. Movies with a time resolution of microseconds per frame reveal that the strain and crack tip do not propagate continuously or at a constant speed. Jumps in the crack tip position indicate pinning of the crack tip for about 1–2 ms followed by jumps faster than 2–6 m s−1, leading to a macroscopically observed average velocity of 0.028–0.055 m s−1. The presented results also give a proof of concept that the described X-ray technique is compatible with studying ultra-fast cracks up to the speed of sound. PMID:27006774

  11. Real-time direct and diffraction X-ray imaging of irregular silicon wafer breakage.

    PubMed

    Rack, Alexander; Scheel, Mario; Danilewsky, Andreas N

    2016-03-01

    Fracture and breakage of single crystals, particularly of silicon wafers, are multi-scale problems: the crack tip starts propagating on an atomic scale with the breaking of chemical bonds, forms crack fronts through the crystal on the micrometre scale and ends macroscopically in catastrophic wafer shattering. Total wafer breakage is a severe problem for the semiconductor industry, not only during handling but also during temperature treatments, leading to million-dollar costs per annum in a device production line. Knowledge of the relevant dynamics governing perfect cleavage along the {111} or {110} faces, and of the deflection into higher indexed {hkl} faces of higher energy, is scarce due to the high velocity of the process. Imaging techniques are commonly limited to depicting only the state of a wafer before the crack and in the final state. This paper presents, for the first time, in situ high-speed crack propagation under thermal stress, imaged simultaneously in direct transmission and diffraction X-ray imaging. It shows how the propagating crack tip and the related strain field can be tracked in the phase-contrast and diffracted images, respectively. Movies with a time resolution of microseconds per frame reveal that the strain and crack tip do not propagate continuously or at a constant speed. Jumps in the crack tip position indicate pinning of the crack tip for about 1-2 ms followed by jumps faster than 2-6 m s(-1), leading to a macroscopically observed average velocity of 0.028-0.055 m s(-1). The presented results also give a proof of concept that the described X-ray technique is compatible with studying ultra-fast cracks up to the speed of sound. PMID:27006774

  12. Differentiation of biological hydroxyapatite compounds by infrared spectroscopy, x-ray diffraction and extended x-ray absorption fine structure

    NASA Astrophysics Data System (ADS)

    Chassot, E.; Oudadesse, H.; Irigaray, J.; Curis, E.; Bénazeth, S.; Nicolis, I.

    2001-12-01

    Pure hydroxyapatite (HAP) and HAP doped with 800 ppm of zinc were implanted in cortical bone of femur diaphysis of ovines [J. L. Irigaray et al., Mater. Clin. Appl. 28, 399 (1999)]. We observed that the doped HAP was better resorbed than pure HAP. The first hypothesis is that zinc acts as a stimulator on macrophage cells and improves quantity and quality of osteoblast cells. The second hypothesis is that zinc yields HAP structure that is better resorbed in biological field. For our experiment we used HAP doped with 3000 ppm of zinc in order to have a good sensitivity. In the present work, chemical studies by inductively coupled plasma absorption emission spectrometry, x ray diffraction, and infrared were carried out to determine the composition of major and trace elements in the doped hydroxyapatite, and the crystallographic structure. These studies can indicate possible modifications induced by the insertion of zinc. We used the extended x-ray absorption fine structure experimental station of LURE (Orsay, France) to try to clarify the atomic surroundings of zinc in doped HAP structure and transformations induced in initial lattice. Despite the low zinc concentration, we got good quality fluorescence mode spectra. These spectra showed medium range order of the material that is consistent with its crystalline form. To perform the analysis, we compared the result obtained with another models like β tricalcium phosphate and we created theoretical models of zinc in substitution of calcium in order to reproduce as well as possible the experimental spectrum. After this study, only two models are coherent with experimental spectrum, zinc in substitution of calcium in site I and zinc in the interstice between the two hydroxydes.

  13. Neutron and X-ray powder diffraction study of skutterudite thermoelectrics

    DOE PAGESBeta

    Wang, H.; Kirkham, M. J.; Watkins, T. R.; Payzant, E. A.; Salvador, J. R.; Thompson, A. J.; Sharp, J.; Brown, D.; Miller, D.

    2016-02-17

    N- and p-type filled-skutterudite materials prepared for thermoelectric power generation modules were analyzed by neutron diffraction at the POWGEN beam line of the Spallation Neutron Source (SNS) and X-ray diffraction (XRD). The skutterudite powders were processed by melt spinning, followed by ball milling and annealing. The n-type material consists of Ba–Yb–Co–Sb and the p-type material consists of Di–Fe–Ni–Sb or Di–Fe–Co–Sb (Di = didymium, an alloy of Pr and Nd). Powders for prototype module fabrication from General Motors and Marlow Industries were analyzed in this study. XRD and neutron diffraction studies confirm that both the n- and p-type materials have cubicmore » symmetry. Structural Rietveld refinements determined the lattice parameters and atomic parameters of the framework and filler atoms. The cage filling fraction was found to depend linearly on the lattice parameter, which in turn depends on the average framework atom size. Ultimately, this knowledge may allow the filling fraction of these skutterudite materials to be purposefully adjusted, thereby tuning the thermoelectric properties.« less

  14. X-ray laser–induced electron dynamics observed by femtosecond diffraction from nanocrystals of Buckminsterfullerene

    PubMed Central

    Abbey, Brian; Dilanian, Ruben A.; Darmanin, Connie; Ryan, Rebecca A.; Putkunz, Corey T.; Martin, Andrew V.; Wood, David; Streltsov, Victor; Jones, Michael W. M.; Gaffney, Naylyn; Hofmann, Felix; Williams, Garth J.; Boutet, Sébastien; Messerschmidt, Marc; Seibert, M. Marvin; Williams, Sophie; Curwood, Evan; Balaur, Eugeniu; Peele, Andrew G.; Nugent, Keith A.; Quiney, Harry M.

    2016-01-01

    X-ray free-electron lasers (XFELs) deliver x-ray pulses with a coherent flux that is approximately eight orders of magnitude greater than that available from a modern third-generation synchrotron source. The power density of an XFEL pulse may be so high that it can modify the electronic properties of a sample on a femtosecond time scale. Exploration of the interaction of intense coherent x-ray pulses and matter is both of intrinsic scientific interest and of critical importance to the interpretation of experiments that probe the structures of materials using high-brightness femtosecond XFEL pulses. We report observations of the diffraction of extremely intense 32-fs nanofocused x-ray pulses by a powder sample of crystalline C60. We find that the diffraction pattern at the highest available incident power significantly differs from the one obtained using either third-generation synchrotron sources or XFEL sources operating at low output power and does not correspond to the diffraction pattern expected from any known phase of crystalline C60. We interpret these data as evidence of a long-range, coherent dynamic electronic distortion that is driven by the interaction of the periodic array of C60 molecular targets with intense x-ray pulses of femtosecond duration. PMID:27626076

  15. High Resolution Triple Axis X-Ray Diffraction Analysis of II-VI Semiconductor Crystals

    NASA Technical Reports Server (NTRS)

    Volz, H. M.; Matyi, R. J.

    1999-01-01

    The objective of this research program is to develop methods of structural analysis based on high resolution triple axis X-ray diffractometry (HRTXD) and to carry out detailed studies of defect distributions in crystals grown in both microgravity and ground-based environments. HRTXD represents a modification of the widely used double axis X-ray rocking curve method for the characterization of grown-in defects in nearly perfect crystals. In a double axis rocking curve experiment, the sample is illuminated by a monochromatic X-ray beam and the diffracted intensity is recorded by a fixed, wide-open detector. The intensity diffracted by the sample is then monitored as the sample is rotated through the Bragg reflection condition. The breadth of the peak, which is often reported as the full angular width at half the maximum intensity (FWHM), is used as an indicator of the amount of defects in the sample. This work has shown that high resolution triple axis X-ray diffraction is an effective tool for characterizing the defect structure in semiconductor crystals, particularly at high defect densities. Additionally, the technique is complimentary to X-ray topography for defect characterization in crystals.

  16. Compact ultrahigh vacuum sample environments for x-ray nanobeam diffraction and imaging

    SciTech Connect

    Evans, P. G. Spalenka, J. W.; Chahine, G.; Grifone, R.; Jacques, V. L. R.; Schülli, T. U.

    2013-11-15

    X-ray nanobeams present the opportunity to obtain structural insight in materials with small volumes or nanoscale heterogeneity. The effective spatial resolution of the information derived from nanobeam techniques depends on the stability and precision with which the relative position of the x-ray optics and sample can be controlled. Nanobeam techniques include diffraction, imaging, and coherent scattering, with applications throughout materials science and condensed matter physics. Sample positioning is a significant mechanical challenge for x-ray instrumentation providing vacuum or controlled gas environments at elevated temperatures. Such environments often have masses that are too large for nanopositioners capable of the required positional accuracy of the order of a small fraction of the x-ray spot size. Similarly, the need to place x-ray optics as close as 1 cm to the sample places a constraint on the overall size of the sample environment. We illustrate a solution to the mechanical challenge in which compact ion-pumped ultrahigh vacuum chambers with masses of 1–2 kg are integrated with nanopositioners. The overall size of the environment is sufficiently small to allow their use with zone-plate focusing optics. We describe the design of sample environments for elevated-temperature nanobeam diffraction experiments demonstrate in situ diffraction, reflectivity, and scanning nanobeam imaging of the ripening of Au crystallites on Si substrates.

  17. X-ray laser-induced electron dynamics observed by femtosecond diffraction from nanocrystals of Buckminsterfullerene.

    PubMed

    Abbey, Brian; Dilanian, Ruben A; Darmanin, Connie; Ryan, Rebecca A; Putkunz, Corey T; Martin, Andrew V; Wood, David; Streltsov, Victor; Jones, Michael W M; Gaffney, Naylyn; Hofmann, Felix; Williams, Garth J; Boutet, Sébastien; Messerschmidt, Marc; Seibert, M Marvin; Williams, Sophie; Curwood, Evan; Balaur, Eugeniu; Peele, Andrew G; Nugent, Keith A; Quiney, Harry M

    2016-09-01

    X-ray free-electron lasers (XFELs) deliver x-ray pulses with a coherent flux that is approximately eight orders of magnitude greater than that available from a modern third-generation synchrotron source. The power density of an XFEL pulse may be so high that it can modify the electronic properties of a sample on a femtosecond time scale. Exploration of the interaction of intense coherent x-ray pulses and matter is both of intrinsic scientific interest and of critical importance to the interpretation of experiments that probe the structures of materials using high-brightness femtosecond XFEL pulses. We report observations of the diffraction of extremely intense 32-fs nanofocused x-ray pulses by a powder sample of crystalline C60. We find that the diffraction pattern at the highest available incident power significantly differs from the one obtained using either third-generation synchrotron sources or XFEL sources operating at low output power and does not correspond to the diffraction pattern expected from any known phase of crystalline C60. We interpret these data as evidence of a long-range, coherent dynamic electronic distortion that is driven by the interaction of the periodic array of C60 molecular targets with intense x-ray pulses of femtosecond duration. PMID:27626076

  18. Soft X-Ray Microscopy at HZB: Zone Plate Development and Imaging Using the Third Order of Diffraction

    NASA Astrophysics Data System (ADS)

    Rehbein, S.; Guttmann, P.; Werner, S.; Schneider, G.

    2011-09-01

    The Helmholtz-Zentrum Berlin (HZB) operates a transmission x-ray microscope (TXM) in the soft x-ray photon energy range with an energy resolution up to E/ΔE = 104 [1]. An approach to achieve ultrahigh spatial resolution with conventional, standard zone plate optics is to employ higher orders of diffraction of the zone plate objective [2]. In this paper, we demonstrate that 11-nm lines and spaces of a multilayer test structure are clearly resolved by the x-ray microscope using the third order of diffraction of a zone plate objective with 20-nm outermost zone width. The disadvantage of high-order imaging is an about one order of magnitude lower diffraction efficiency of the used zone plates employed in the third order compared to the first order of diffraction. In addition, the measured background signal in the TXM images is no longer negligible. Therefore, we worked on the fabrication of zone plates with sub-20-nm outermost zone width to increase the spatial resolution in the first order of diffraction. A new high-resolution 100-keV e-beam lithography system from VISTEC, which was recently installed at the Helmholtz-Zentrum Berlin, makes these developments possible. Initial results on zone plates with an outermost zone width down to 15 nm exposed with the new e-beam system are presented. Furthermore, the contrast transfer function of the transmission x-ray microscope operating in partial coherence mode is measured by using the first and third diffraction order of the zone plate objective.

  19. Soft X-Ray Microscopy at HZB: Zone Plate Development and Imaging Using the Third Order of Diffraction

    SciTech Connect

    Rehbein, S.; Guttmann, P.; Werner, S.; Schneider, G.

    2011-09-09

    The Helmholtz-Zentrum Berlin (HZB) operates a transmission x-ray microscope (TXM) in the soft x-ray photon energy range with an energy resolution up to E/{Delta}E = 10{sup 4}. An approach to achieve ultrahigh spatial resolution with conventional, standard zone plate optics is to employ higher orders of diffraction of the zone plate objective. In this paper, we demonstrate that 11-nm lines and spaces of a multilayer test structure are clearly resolved by the x-ray microscope using the third order of diffraction of a zone plate objective with 20-nm outermost zone width. The disadvantage of high-order imaging is an about one order of magnitude lower diffraction efficiency of the used zone plates employed in the third order compared to the first order of diffraction. In addition, the measured background signal in the TXM images is no longer negligible. Therefore, we worked on the fabrication of zone plates with sub-20-nm outermost zone width to increase the spatial resolution in the first order of diffraction. A new high-resolution 100-keV e-beam lithography system from VISTEC, which was recently installed at the Helmholtz-Zentrum Berlin, makes these developments possible. Initial results on zone plates with an outermost zone width down to 15 nm exposed with the new e-beam system are presented. Furthermore, the contrast transfer function of the transmission x-ray microscope operating in partial coherence mode is measured by using the first and third diffraction order of the zone plate objective.

  20. Single-shot femtosecond x-ray diffraction from randomly oriented ellipsoidal nanoparticles

    NASA Astrophysics Data System (ADS)

    Bogan, M. J.; Boutet, S.; Barty, A.; Benner, W. H.; Frank, M.; Lomb, L.; Shoeman, R.; Starodub, D.; Seibert, M. M.; Hau-Riege, S. P.; Woods, B.; Decorwin-Martin, P.; Bajt, S.; Schulz, J.; Rohner, U.; Iwan, B.; Timneanu, N.; Marchesini, S.; Schlichting, I.; Hajdu, J.; Chapman, H. N.

    2010-09-01

    Coherent diffractive imaging of single particles using the single-shot “diffract and destroy” approach with an x-ray free electron laser (FEL) was recently demonstrated. A high-resolution low-noise coherent diffraction pattern, representative of the object before it turns into a plasma and explodes, results from the interaction of the FEL with the particle. Iterative phase retrieval algorithms are used to reconstruct two-dimensional projection images of the object from the recorded intensities alone. Here we describe the first single-shot diffraction data set that mimics the data proposed for obtaining 3D structure from identical particles. Ellipsoidal iron oxide nanoparticles (250nm×50nm) were aerosolized and injected through an aerodynamic lens stack into a soft x-ray FEL. Particle orientation was not controlled with this injection method. We observed that, at the instant the x-ray pulse interacts with the particle, a snapshot of the particle’s orientation is encoded in the diffraction pattern. The results give credence to one of the technical concepts of imaging individual nanometer and subnanometer-sized objects such as single molecules or larger clusters of molecules using hard x-ray FELs and will be used to help develop robust algorithms for determining particle orientations and 3D structure.

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

    NASA Astrophysics Data System (ADS)

    Ghammraoui, B.; Tabary, J.; Pouget, S.; Paulus, C.; Moulin, V.; Verger, L.; Duvauchelle, Ph.

    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.

  2. X-Ray Line Spectroscopy of Massive X-Ray Binaries

    NASA Technical Reports Server (NTRS)

    Liedahl, D. A.; Sako, M.; Wojdowski, P. S.; Paerels, F.; Kahn, S. M.

    2000-01-01

    Spectra from ASCA have provided the most, detailed view to date of the X-ray spectral properties of stellar winds in massive X-ray binaries. Using detailed atomic models that account for recombination cascade kinetics, we have reexamined archival data from Vela X-1 and Cen X-3 in the context of simple models of their wind geometries and velocity distributions. Our approach emphasizes apparent differential emission measure (DEM) distributions, and their dependence on orbital phase and wind parameters. A grid of theoretical DEM distributions is used to generate model spectra, which are compared to the data. We obtain good fits, and derive constraints oil the stellar wind parameters. We provide a summary of the method, and show that, even though the companion stars in Vela X-1 and Cen X-3 have comparable mass-loss rates, the winds in these two systems are dramatically different, in character.

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

    NASA Astrophysics Data System (ADS)

    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.

  4. X-ray diffraction and electron spectroscopy of epitaxial molecular C sub 60 films

    SciTech Connect

    Tong, W.M.; Ohlberg, D.A.A.; You, H.K.; Williams, R.S.; Anz, S.J.; Alvarez, M.M.; Whetten, R.L.; Rubin, Y.; Diederich, F.N. )

    1991-06-13

    Films of the new carbon allotrope, molecular C{sub 60}, also known as Buckminsterfullerene, have been grown on Si(111) substrates by molecular beam epitaxy. The films have been characterized with X-ray 2{theta} diffraction, X-ray photoelectron spectroscopy, Auger electron spectroscopy, and electron energy loss spectroscopy. The diffraction data from oriented films show that close-packed planes of C{sub 60} molecules are stacked parallel to the substrate surface but that the correlation length for X-ray scattering is less than 200 {angstrom}. The electron spectroscopic data show that the C atoms of C{sub 60} are essentially sp{sup 2}-bonded, but there are significant differences with respect to graphite.

  5. Coherent X-Ray Diffraction Imaging of Morphology and Strain in Nanomaterials

    NASA Astrophysics Data System (ADS)

    Harder, Ross; Robinson, Ian K.

    2013-09-01

    The last decade has seen a remarkable surge in x-ray characterization methods (Willmott, An Introduction to Synchrotron Radiation, John Wiley & Sons, Inc., New York, 2011). Imaging with x-rays has evolved from simple radiography, to image internal structure and diagnose injury, to a full-fledged tool for nanoscale characterization (Holt et al., Annu Rev Mater Res 43:1, 2013). Central to this development has been the advent of high-brilliance synchrotron and free electron laser sources of x-rays. The high degree of spacial coherence of the resulting beams has enabled novel imaging methods. Of these, coherent diffraction imaging has proven highly successful at imaging the structure in nano materials (Miao et al., Nature 400:342, 1999). In addition, this imaging method can be combined with Bragg diffraction to image strain with high sensitivity (Pfeifer et al., Nature 442:63, 2006; Robinson and Harder, Nat Mater 8:291, 2009).

  6. Perspective: Structural dynamics in condensed matter mapped by femtosecond x-ray diffraction

    SciTech Connect

    Elsaesser, T.; Woerner, M.

    2014-01-14

    Ultrashort soft and hard x-ray pulses are sensitive probes of structural dynamics on the picometer length and femtosecond time scales of electronic and atomic motions. Recent progress in generating such pulses has initiated new directions of condensed matter research, exploiting a variety of x-ray absorption, scattering, and diffraction methods to probe photoinduced structural dynamics. Atomic motion, changes of local structure and long-range order, as well as correlated electron motion and charge transfer have been resolved in space and time, providing a most direct access to the physical mechanisms and interactions driving reversible and irreversible changes of structure. This perspective combines an overview of recent advances in femtosecond x-ray diffraction with a discussion on ongoing and future developments.

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

    PubMed

    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. PMID:25375529

  8. Spectrometer for hard X-ray free-electron laser based on diffraction focusing.

    PubMed

    Kohn, V G; Gorobtsov, O Y; Vartanyants, I A

    2013-03-01

    X-ray free-electron lasers (XFELs) generate sequences of ultra-short spatially coherent pulses of X-ray radiation. A diffraction focusing spectrometer (DFS), which is able to measure the whole energy spectrum of the radiation of a single XFEL pulse with an energy resolution of ΔE/E 2 × 10(-6), is proposed. This is much better than for most modern X-ray spectrometers. Such resolution allows one to resolve the fine spectral structure of the XFEL pulse. The effect of diffraction focusing occurs in a single-crystal plate due to dynamical scattering, and is similar to focusing in a Pendry lens made from a metamaterial with a negative refraction index. Such a spectrometer is easier to operate than those based on bent crystals. It is shown that the DFS can be used in a wide energy range from 5 keV to 20 keV. PMID:23412482

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

    SciTech Connect

    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.

  10. Structural studies of homoisoflavonoids: NMR spectroscopy, X-ray diffraction, and theoretical calculations

    NASA Astrophysics Data System (ADS)

    Sievänen, Elina; Toušek, Jaromír; Lunerová, Kamila; Marek, Jaromír; Jankovská, Dagmar; Dvorská, Margita; Marek, Radek

    2010-08-01

    In this article we present a detailed structural investigation for five homoisoflavonoids, molecules important from the pharmacological point of view. For studying the electron distribution as well as its influence on the physicochemical properties, NMR spectroscopy, X-ray diffraction, and theoretical calculations have been used. Nuclear magnetic shieldings obtained by using DFT calculations for optimized molecular geometries are correlated with the experimentally determined chemical shifts. The theoretical data are well in agreement with the experimental values. The single crystal X-ray structures of homoisoflavonoid derivatives 1, 3, and 4 have been solved. The molecular geometries and crystal packing determined by X-ray diffraction are used for characterizing the intermolecular interactions. Electron distribution is crucial for the stability of radicals and hence the antioxidant efficiency of flavonoid structures. The hydrogen bonding governs the formation of complexes of homoisoflavonoids with biological targets.

  11. X-ray diffraction of indirect flight muscle from Drosohila in vivo

    SciTech Connect

    Irving, T.

    2007-02-09

    The indirect flight muscle (IFM) of the fruit fly, Drosophila, represents a powerful model system for integrated structure and function studies because of the ease of genetically manipulating this organism. Recent advances in synchrotron technology have allowed collection of high quality two dimensional x-ray fiber diffraction patterns from the IFM of living fruit flies both at rest and during tethered flight. Based on many decades of x-ray and electron microscopic studies of vertebrate muscle and IFM from the waterbug, Lethocerus, there now exists a framework for interpreting changes in the x-ray diffraction patterns in terms of structural changes at the myofilament level. These developments allow testing of hypotheses concerning muscle function in a truly in vivo system.

  12. X-ray bumps, iron K-alpha lines, and X-ray suppression by obscuring tori in Seyfert galaxies

    NASA Technical Reports Server (NTRS)

    Krolik, Julian H.; Madau, Piero; Zycki, Piotr T.

    1994-01-01

    We investigate the X-ray spectral properties of unobscured type 1 and obscured type 2 Seyferts as predicted by the unified Seyfert scheme. We consider the reprocessing of X-ray photons by photoelectric absorption, iron fluorescence, and Compton downscattering in the obscuring tori surrounding these active nuclei, and compute by Monte Carlo methods the reprocessed spectra as a function of the viewing angle. Depending on the optical depth and shape of the torus, and on the viewing angle, the X-ray flux can be suppressed by substantial factors when our line of sight is obscured. We show that an immediate consequence of the existence of an obscuring thick torus is the production in the spectra of type 1 Seyfert galaxies of a bump in the continuum above 10-20 keV and an Fe K-alpha line with significant equivalent width. In those type 2 Seyferts for which the hard X-ray spectrum has been substantially suppressed, the equivalent width of the Fe K-alpha line in the transmitted spectrum can be very large.

  13. Weak Hard X-Ray Emission from Broad Absorption Line Quasars: Evidence for Intrinsic X-Ray Weakness

    NASA Astrophysics Data System (ADS)

    Luo, B.; Brandt, W. N.; Alexander, D. M.; Stern, D.; Teng, S. H.; Arévalo, P.; Bauer, F. E.; Boggs, S. E.; Christensen, F. E.; Comastri, A.; Craig, W. W.; Farrah, D.; Gandhi, P.; Hailey, C. J.; Harrison, F. A.; Koss, M.; Ogle, P.; Puccetti, S.; Saez, C.; Scott, A. E.; Walton, D. J.; Zhang, W. W.

    2014-10-01

    We report NuSTAR observations of a sample of six X-ray weak broad absorption line (BAL) quasars. These targets, at z = 0.148-1.223, are among the optically brightest and most luminous BAL quasars known at z < 1.3. However, their rest-frame ≈2 keV luminosities are 14 to >330 times weaker than expected for typical quasars. Our results from a pilot NuSTAR study of two low-redshift BAL quasars, a Chandra stacking analysis of a sample of high-redshift BAL quasars, and a NuSTAR spectral analysis of the local BAL quasar Mrk 231 have already suggested the existence of intrinsically X-ray weak BAL quasars, i.e., quasars not emitting X-rays at the level expected from their optical/UV emission. The aim of the current program is to extend the search for such extraordinary objects. Three of the six new targets are weakly detected by NuSTAR with <~ 45 counts in the 3-24 keV band, and the other three are not detected. The hard X-ray (8-24 keV) weakness observed by NuSTAR requires Compton-thick absorption if these objects have nominal underlying X-ray emission. However, a soft stacked effective photon index (Γeff ≈ 1.8) for this sample disfavors Compton-thick absorption in general. The uniform hard X-ray weakness observed by NuSTAR for this and the pilot samples selected with <10 keV weakness also suggests that the X-ray weakness is intrinsic in at least some of the targets. We conclude that the NuSTAR observations have likely discovered a significant population (gsim 33%) of intrinsically X-ray weak objects among the BAL quasars with significantly weak <10 keV emission. We suggest that intrinsically X-ray weak quasars might be preferentially observed as BAL quasars.

  14. Weak hard X-ray emission from broad absorption line quasars: evidence for intrinsic X-ray weakness

    SciTech Connect

    Luo, B.; Brandt, W. N.; Scott, A. E.; Alexander, D. M.; Gandhi, P.; Stern, D.; Teng, S. H.; Arévalo, P.; Bauer, F. E.; Boggs, S. E.; Craig, W. W.; Christensen, F. E.; Comastri, A.; Farrah, D.; Hailey, C. J.; Harrison, F. A.; Koss, M.; Ogle, P.; Puccetti, S.; Saez, C.; and others

    2014-10-10

    We report NuSTAR observations of a sample of six X-ray weak broad absorption line (BAL) quasars. These targets, at z = 0.148-1.223, are among the optically brightest and most luminous BAL quasars known at z < 1.3. However, their rest-frame ≈2 keV luminosities are 14 to >330 times weaker than expected for typical quasars. Our results from a pilot NuSTAR study of two low-redshift BAL quasars, a Chandra stacking analysis of a sample of high-redshift BAL quasars, and a NuSTAR spectral analysis of the local BAL quasar Mrk 231 have already suggested the existence of intrinsically X-ray weak BAL quasars, i.e., quasars not emitting X-rays at the level expected from their optical/UV emission. The aim of the current program is to extend the search for such extraordinary objects. Three of the six new targets are weakly detected by NuSTAR with ≲ 45 counts in the 3-24 keV band, and the other three are not detected. The hard X-ray (8-24 keV) weakness observed by NuSTAR requires Compton-thick absorption if these objects have nominal underlying X-ray emission. However, a soft stacked effective photon index (Γ{sub eff} ≈ 1.8) for this sample disfavors Compton-thick absorption in general. The uniform hard X-ray weakness observed by NuSTAR for this and the pilot samples selected with <10 keV weakness also suggests that the X-ray weakness is intrinsic in at least some of the targets. We conclude that the NuSTAR observations have likely discovered a significant population (≳ 33%) of intrinsically X-ray weak objects among the BAL quasars with significantly weak <10 keV emission. We suggest that intrinsically X-ray weak quasars might be preferentially observed as BAL quasars.

  15. Magnetic symmetries in neutron and resonant x-ray Bragg diffraction patterns of four iridium oxides

    NASA Astrophysics Data System (ADS)

    Lovesey, S. W.; Khalyavin, D. D.; Manuel, P.; Chapon, L. C.; Cao, G.; Qi, T. F.

    2012-12-01

    The magnetic properties of Sr2IrO4, Na2IrO3, Sr3Ir2O7 and CaIrO3 are discussed, principally in the light of experimental data in recent literature for Bragg intensities measured in x-ray diffraction with enhancement at iridium L-absorption edges. The electronic structure factors we report, which incorporate parity-even and acentric entities, serve the immediate purpose of making full use of crystal and magnetic symmetry to refine our knowledge of the magnetic properties of the four iridates from resonant x-ray diffraction data. They also offer a platform on which to interpret future investigations, using dichroic signals, resonant x-ray diffraction and neutron diffraction, for example, as well as ab initio calculations of electronic structure. Unit-cell structure factors, suitable for x-ray Bragg diffraction enhanced by an electric dipole-electric dipole (E1-E1) event, reveal exactly which iridium multipoles are visible, e.g., a magnetic dipole parallel to the crystal c-axis (z-axis) and an electric quadrupole with yz-like symmetry in the specific case of CaIrO3. Magnetic space-groups are assigned to Sr2IrO4, Sr3Ir2O7 and CaIrO3, namely, PIcca, PAban and Cm‧cm‧, respectively, in the Belov-Neronova-Smirnova notation. The assignment for Sr2IrO4 is possible because of our new high-resolution neutron diffraction data, gathered on a powder sample. In addition, the new data are used to show that the ordered magnetic moment of an Ir4+ ion in Sr2IrO4 does not exceed 0.29(4) μB. Na2IrO3 has two candidate magnetic space-groups that are not resolved with currently available resonant x-ray data.

  16. Mapping Strain in Nanocrystalline Nitinol: an X-ray Diffraction Method (SULI paper)

    SciTech Connect

    Bibee, Mathew; /SLAC, SSRL

    2006-01-04

    Understanding the mechanical properties of biomedical devices is critical in predicting and preventing their failure in the body. Such knowledge is essential, for example, in the design of biomedical stents, which must undergo repeated strain over their ten year lifetimes without breaking. Computational models are used to predict mechanical response of a device, but these models are not complete; there are significant deviations from the predictions, especially when devices are subjected to repeated multi-axial loads. Improving these models requires comparisons with actual measurements of strained nitinol. Local measurements of the full strain tensor can be made using X-ray diffraction techniques, but they are currently limited to materials whose grain size is larger than the X-ray beam size or require several diffraction patterns produced by rotation of the sample. Nitinol stents are nanocrystalline, with grains smaller than any available X-ray beam. We present a method for measuring the local strain in a nanocrystalline material from a single X-ray diffraction pattern by extending current powder diffraction techniques. The components of the strain tensor are mapped onto a displacement ellipsoid, which is then reconstructed from diffraction data through Bragg's law and least-squares fitting. Using simulated diffraction data, we performed sensitivity tests to examine how the accuracy of the method depends on how much of the diffraction pattern is measured. We found that strain can be accurately calculated from measurements of at least three diffraction arcs of at least 20{sup o} in length. Thus we believe that our method is a viable approach to calculating strain provided a sufficient amount of diffraction pattern is recorded.

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

    NASA Technical Reports Server (NTRS)

    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.; Achilles, C. N.; Downs, R. T.; Farmer, J. D.; Crisp, J. A.; Morookian, J. M.; Des Marais, D. J.; Grotzinger, J. P.; Sarrazin, P.; Yen, A. S.

    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.

  18. Three-dimensional imaging of dislocations by X-ray diffraction laminography

    NASA Astrophysics Data System (ADS)

    Hänschke, D.; Helfen, L.; Altapova, V.; Danilewsky, A.; Baumbach, T.

    2012-12-01

    Synchrotron radiation laminography with X-ray diffraction contrast enables three-dimensional imaging of dislocations in monocrystalline wafers. We outline the principle of the technique, the required experimental conditions, and the reconstruction procedure. The feasibility and the potential of the method are demonstrated by three-dimensional imaging of dislocation loops in an indent-damaged and annealed silicon wafer.

  19. Structural Order-Disorder Transformations Monitored by X-Ray Diffraction and Photoluminescence

    ERIC Educational Resources Information Center

    Lima, R. C.; Paris, E. C.; Leite, E. R.; Espinosa, J. W. M.; Souza, A. G.; Longo, E.

    2007-01-01

    A study was conducted to examine the structural order-disorder transformation promoted by controlled heat treatment using X-ray diffraction technique (XRD) and photoluminescence (PL) techniques as tools to monitor the degree of structural order. The experiment was observed to be versatile and easily achieved with low cost which allowed producing…

  20. Characterization of calcium crystals in Abelia using x-ray diffraction and electron microscopes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Localization, chemical composition, and morphology of calcium crystals in leaves and stems of Abelia mosanensis and A. ×grandiflora were analyzed with a variable pressure scanning electron microscope (VP-SEM) equipped with an X-ray diffraction system, low temperature SEM (LT-SEM) and a transmission ...

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

    DOEpatents

    Smither, Robert K.

    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.

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

    SciTech Connect

    Veluraja, K.; Vennila, K.N.; Umamakeshvari, K.; Jasmine, A.; Velmurugan, D.

    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.

  3. X-RAY POWDER DIFFRACTION SYSTEM FOR CHEMICAL SPECIATION OF PARTICULATE AEROSOL SAMPLES

    EPA Science Inventory

    An x-ray powder diffraction system has been developed for the automated measurement and analysis of particulate aerosol samples. The system is optimized to process samples with particle loadings of about 100 micrograms/sq cm which are acquired with dichotomous air samplers. A pos...

  4. X-Ray Diffraction Study of L2005 AG17 (IDPs) by Using SR

    NASA Technical Reports Server (NTRS)

    Ohsumi, K. O.; Hagiya, K. H.; Zolensky, M. E.

    2002-01-01

    X-ray diffraction study revealed the existence of magnetite and new type of pyrrhotite with the chemical formula of Fe0.56S in L2005 AG17. Considering the total chemical formula of Fe0.83S, residual iron in amorphous state might exist in this sample. Additional information is contained in the original extended abstract.

  5. Parametric X-ray Radiation and Diffraction Bremsstrahlung from Moderately Relativistic Electrons in Pyrolytic Graphite Crystal

    SciTech Connect

    Vagner, A. R.; Potylitsyn, A. P.; Kuznecov, S. I.; Uglov, S. R.; Zabaev, V. N.; Razin, S. V.

    2007-11-26

    Spectral maxima of parametric X-ray radiation (PXR) and diffraction bremsstrahlung (DBS) from moderately relativistic electrons and bremsstrahlung interacting with crystal have been observed. The maxima position of PXR and DBS depends on the crystal orientation angle and corresponds to theoretical calculations.

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

    PubMed Central

    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

    2008-01-01

    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- to 90-nm resolution by using two different tabletop coherent soft x-ray sources—a soft x-ray laser and a high-harmonic source. We also use field curvature correction that allows high numerical aperture imaging and near-diffraction-limited resolution of 1.5λ. A tabletop soft x-ray diffraction microscope should find broad applications in biology, nanoscience, and materials science because of its simple optical design, high resolution, large depth of field, 3D imaging capability, scalability to shorter wavelengths, and ultrafast temporal resolution. PMID:18162534

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

    NASA Astrophysics Data System (ADS)

    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.

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

    ERIC Educational Resources Information Center

    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…

  9. Development of an x-ray diffraction camera used in magnetic fields up to 10 T

    SciTech Connect

    Mitsui, Yoshifuru; Takahashi, Kohki; Watanabe, Kazuo; Koyama, Keiichi

    2011-12-15

    A high-field x-ray diffraction (HF-XRD) camera was developed to observe structural changes of magnetic materials in magnetic fields up to 10 T. The instrument mainly consists of a Debye-Scherrer-type camera with a diameter of 80.1 mm, a 10-T cryocooled superconducting magnet with a 100-mm room-temperature bore, an x-ray source, a power supply, and a chiller for the x-ray source. An x-ray detector (image plate) in the HF-XRD camera can be taken out and inserted into the magnet without changing the sample position. The performance of the instrument was tested by measuring the HF-XRD for silicon and ferromagnetic MnBi powders. A change of x-ray diffraction pattern was observed due to the magnetic orientation of MnBi, showing that the instrument is useful for studying field-induced orientation processes and structural properties of field-controlled materials.

  10. Development of an x-ray diffraction camera used in magnetic fields up to 10 T.

    PubMed

    Mitsui, Yoshifuru; Koyama, Keiichi; Takahashi, Kohki; Watanabe, Kazuo

    2011-12-01

    A high-field x-ray diffraction (HF-XRD) camera was developed to observe structural changes of magnetic materials in magnetic fields up to 10 T. The instrument mainly consists of a Debye-Scherrer-type camera with a diameter of 80.1 mm, a 10-T cryocooled superconducting magnet with a 100-mm room-temperature bore, an x-ray source, a power supply, and a chiller for the x-ray source. An x-ray detector (image plate) in the HF-XRD camera can be taken out and inserted into the magnet without changing the sample position. The performance of the instrument was tested by measuring the HF-XRD for silicon and ferromagnetic MnBi powders. A change of x-ray diffraction pattern was observed due to the magnetic orientation of MnBi, showing that the instrument is useful for studying field-induced orientation processes and structural properties of field-controlled materials. PMID:22225246

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

    NASA Astrophysics Data System (ADS)

    Alexeyev, V. I.; Eliseyev, A. N.; Irribarra, E.; Kishin, I. A.; Kubankin, A. S.; Nazhmudinov, R. M.

    2016-08-01

    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.

  12. X-ray imaging and diffraction from surface phonons on GaAs

    NASA Astrophysics Data System (ADS)

    Sauer, W.; Streibl, M.; Metzger, T. H.; Haubrich, A. G. C.; Manus, S.; Wixforth, A.; Peisl, J.; Mazuelas, A.; Härtwig, J.; Baruchel, J.

    1999-09-01

    Surface acoustic waves (SAWs) are excited on the GaAs (001) surface by using interdigital transducers, designed for frequencies of up to 900 MHz. The emitted phonons with wavelengths down to 3.5 μm are visualized and characterized by combined x-ray diffraction techniques. Using stroboscopic topography, the SAW emission of a parallel and a focusing transducer geometry are imaged. High-resolution x-ray diffraction profiles show up to 12 phonon-induced satellite reflections besides the GaAs (004) reflection, with a width of 9 arcsec each. The diffraction pattern is simulated numerically, applying the kinematical scattering theory to a model crystal. From fits to measured diffraction profiles at different excitation voltages, the SAW amplitudes were calculated and found to be in the sub-nm range.

  13. Simultaneous, single-pulse, synchrotron x-ray imaging and diffraction under gas gun loading.

    PubMed

    Fan, D; Huang, J W; Zeng, X L; Li, Y; E, J C; Huang, J Y; Sun, T; Fezzaa, K; Wang, Z; Luo, S N

    2016-05-01

    We develop a mini gas gun system for simultaneous, single-pulse, x-ray diffraction and imaging under high strain-rate loading at the beamline 32-ID of the Advanced Photon Source. In order to increase the reciprocal space covered by a small-area detector, a conventional target chamber is split into two chambers: a narrowed measurement chamber and a relief chamber. The gas gun impact is synchronized with synchrotron x-ray pulses and high-speed cameras. Depending on a camera's capability, multiframe imaging and diffraction can be achieved. The proof-of-principle experiments are performed on single-crystal sapphire. The diffraction spots and images during impact are analyzed to quantify lattice deformation and fracture; fracture is dominated by splitting cracks followed by wing cracks, and diffraction peaks are broadened likely due to mosaic spread. Our results demonstrate the potential of such multiscale measurements for studying high strain-rate phenomena at dynamic extremes. PMID:27250438

  14. Application of a pnCCD in X-ray diffraction: a three-dimensional X-ray detector.

    PubMed

    Leitenberger, Wolfram; Hartmann, Robert; Pietsch, Ullrich; Andritschke, Robert; Starke, Ines; Strüder, Lothar

    2008-09-01

    The first application of a pnCCD detector for X-ray scattering experiments using white synchrotron radiation at BESSY II is presented. A Cd arachidate multilayer was investigated in reflection geometry within the energy range 7 keV < E < 35 keV. At fixed angle of incidence the two-dimensional diffraction pattern containing several multilayer Bragg peaks and respective diffuse-resonant Bragg sheets were observed. Since every pixel of the detector is able to determine the energy of every incoming photon with a resolution DeltaE/E approximately 10(-2), a three-dimensional dataset is finally obtained. In order to achieve this energy resolution the detector was operated in the so-called single-photon-counting mode. A full dataset was evaluated taking into account all photons recorded within 10(5) detector frames at a readout rate of 200 Hz. By representing the data in reciprocal-space coordinates, it becomes obvious that this experiment with the pnCCD detector provides the same information as that obtained by combining a large number of monochromatic scattering experiments using conventional area detectors. PMID:18728315

  15. Specific features of two diffraction schemes for a widely divergent X-ray beam

    SciTech Connect

    Avetyan, K. T.; Levonyan, L. V.; Semerjian, H. S.; Arakelyan, M. M. Badalyan, O. M.

    2015-03-15

    We investigated the specific features of two diffraction schemes for a widely divergent X-ray beam that use a circular diaphragm 30–50 μm in diameter as a point source of characteristic radiation. In one of the schemes, the diaphragm was set in front of the crystal (the diaphragm-crystal (d-c) scheme); in the other, it was installed behind the crystal (the crystal-diaphragm (c-d) scheme). It was established that the diffraction image in the c-d scheme is a topographic map of the investigated crystal area. In the d-c scheme at L = 2l (l and L are the distances between the crystal and the diaphragm and between the photographic plate and the diaphragm, respectively), the branches of hyperbolas formed in this family of planes (hkl) by the characteristic K{sub α} and K{sub β} radiations, including higher order reflections, converge into one straight line. It is experimentally demonstrated that this convergence is very sensitive to structural inhomogeneities in the crystal under study.

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

    PubMed Central

    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

  17. Photoelectron diffraction from laser-aligned molecules with X-ray free-electron laser pulses

    PubMed Central

    Nakajima, Kyo; Teramoto, Takahiro; Akagi, Hiroshi; Fujikawa, Takashi; Majima, Takuya; Minemoto, Shinichirou; Ogawa, Kanade; Sakai, Hirofumi; Togashi, Tadashi; Tono, Kensuke; Tsuru, Shota; Wada, Ken; Yabashi, Makina; Yagishita, Akira

    2015-01-01

    We report on the measurement of deep inner-shell 2p X-ray photoelectron diffraction (XPD) patterns from laser-aligned I2 molecules using X-ray free-electron laser (XFEL) pulses. The XPD patterns of the I2 molecules, aligned parallel to the polarization vector of the XFEL, were well matched with our theoretical calculations. Further, we propose a criterion for applying our molecular-structure-determination methodology to the experimental XPD data. In turn, we have demonstrated that this approach is a significant step toward the time-resolved imaging of molecular structures. PMID:26369428

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

    NASA Technical Reports Server (NTRS)

    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.

  19. Protein crystallography: From X-ray diffraction spots to a three dimensional image

    SciTech Connect

    Terwilliger, T.C.; Berendzen, J.

    1998-02-25

    Proteins are remarkable molecular machines that are essential for life. They can do many things ranging from the precise control of blood clotting to synthesizing complex organic compounds. Pictures of protein molecules are in high demand in biotechnology because they are important for applications such as drug discovery and for engineering enzymes for commercial use. X-ray crystallography is the most common method for determining the three-dimensional structures of protein molecules. When a crystal of a protein is placed in an X-ray beam, scattering of X-rays off the ordered molecules produces a diffraction pattern that can be measured on a position-sensitive CCD or image-plate detector. Protein crystals typically contain thousands of atoms and the diffraction data are generally measured to relatively low resolution. Consequently the direct methods approaches generally cannot be applied. Instead, if the crystal is modified by adding metal atoms at specific sites or by tuning the wavelength of the X-rays to cross an absorption edge of a metal atom in the crystal, then the information from these additional measurements is sufficient to first identify the /locations of the metal atoms. This information is then used along with the diffraction data to make a three-dimensional picture of electron densities. This picture can be used to determine the position of most or all of the atoms in the protein.

  20. Ptychographic coherent x-ray diffractive imaging in the water window.

    PubMed

    Giewekemeyer, K; Beckers, M; Gorniak, T; Grunze, M; Salditt, T; Rosenhahn, A

    2011-01-17

    Coherent x-ray diffractive microscopy enables full reconstruction of the complex transmission function of an isolated object to diffraction-limited resolution without relying on any optical elements between the sample and detector. In combination with ptychography, also specimens of unlimited lateral extension can be imaged. Here we report on an application of ptychographic coherent diffractive imaging (PCDI) in the soft x-ray regime, more precisely in the so-called water window of photon energies where the high scattering contrast between carbon and oxygen is well-suited to image biological samples. In particular, we have reconstructed the complex sample transmission function of a fossil diatom at a photon energy of 517 eV. In imaging a lithographically fabricated test sample a resolution on the order of 50 nm (half-period length) has been achieved. Along with this proof-of-principle for PCDI at soft x-ray wavelengths, we discuss the experimental and technical challenges which can occur especially for soft x-ray PCDI. PMID:21263642

  1. A laboratory based system for Laue micro x-ray diffraction

    SciTech Connect

    Advanced Light Source; Tamura, Nobumichi; Lynch, P.A.; Stevenson, A.W.; Liang, D.; Parry, D.; Wilkins, S.; Tamura, N.

    2007-02-28

    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 mum 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 percent 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 (37 References).

  2. High-precision laser-assisted absolute determination of x-ray diffraction angles

    SciTech Connect

    Kubicek, K.; Braun, J.; Bruhns, H.; Crespo Lopez-Urrutia, J. R.; Mokler, P. H.; Ullrich, J.

    2012-01-15

    A novel technique for absolute wavelength determination in high-precision crystal x-ray spectroscopy recently introduced has been upgraded reaching unprecedented accuracies. The method combines visible laser beams with the Bond method, where Bragg angles ({theta} and -{theta}) are determined without any x-ray reference lines. Using flat crystals this technique makes absolute x-ray wavelength measurements feasible even at low x-ray fluxes. The upgraded spectrometer has been used in combination with first experiments on the 1s2p {sup 1}P{sub 1}{yields} 1s{sup 2} {sup 1}S{sub 0} w-line in He-like argon. By resolving a minute curvature of the x-ray lines the accuracy reaches there the best ever reported value of 1.5 ppm. The result is sensitive to predicted second-order QED contributions at the level of two-electron screening and two-photon radiative diagrams and will allow for the first time to benchmark predicted binding energies for He-like ions at this level of precision.

  3. X-ray laser diffraction for structure determination of the rhodopsin-arrestin complex

    PubMed Central

    Zhou, X. Edward; Gao, Xiang; Barty, Anton; Kang, Yanyong; He, Yuanzheng; Liu, Wei; Ishchenko, Andrii; White, Thomas A.; Yefanov, Oleksandr; Han, Gye Won; Xu, Qingping; de Waal, Parker W.; Suino-Powell, Kelly M.; Boutet, Sébastien; Williams, Garth J.; Wang, Meitian; Li, Dianfan; Caffrey, Martin; Chapman, Henry N.; Spence, John C.H.; Fromme, Petra; Weierstall, Uwe; Stevens, Raymond C.; Cherezov, Vadim; Melcher, Karsten; Xu, H. Eric

    2016-01-01

    Serial femtosecond X-ray crystallography (SFX) using an X-ray free electron laser (XFEL) is a recent advancement in structural biology for solving crystal structures of challenging membrane proteins, including G-protein coupled receptors (GPCRs), which often only produce microcrystals. An XFEL delivers highly intense X-ray pulses of femtosecond duration short enough to enable the collection of single diffraction images before significant radiation damage to crystals sets in. Here we report the deposition of the XFEL data and provide further details on crystallization, XFEL data collection and analysis, structure determination, and the validation of the structural model. The rhodopsin-arrestin crystal structure solved with SFX represents the first near-atomic resolution structure of a GPCR-arrestin complex, provides structural insights into understanding of arrestin-mediated GPCR signaling, and demonstrates the great potential of this SFX-XFEL technology for accelerating crystal structure determination of challenging proteins and protein complexes. PMID:27070998

  4. X-ray laser diffraction for structure determination of the rhodopsin-arrestin complex.

    PubMed

    Zhou, X Edward; Gao, Xiang; Barty, Anton; Kang, Yanyong; He, Yuanzheng; Liu, Wei; Ishchenko, Andrii; White, Thomas A; Yefanov, Oleksandr; Han, Gye Won; Xu, Qingping; de Waal, Parker W; Suino-Powell, Kelly M; Boutet, Sébastien; Williams, Garth J; Wang, Meitian; Li, Dianfan; Caffrey, Martin; Chapman, Henry N; Spence, John C H; Fromme, Petra; Weierstall, Uwe; Stevens, Raymond C; Cherezov, Vadim; Melcher, Karsten; Xu, H Eric

    2016-01-01

    Serial femtosecond X-ray crystallography (SFX) using an X-ray free electron laser (XFEL) is a recent advancement in structural biology for solving crystal structures of challenging membrane proteins, including G-protein coupled receptors (GPCRs), which often only produce microcrystals. An XFEL delivers highly intense X-ray pulses of femtosecond duration short enough to enable the collection of single diffraction images before significant radiation damage to crystals sets in. Here we report the deposition of the XFEL data and provide further details on crystallization, XFEL data collection and analysis, structure determination, and the validation of the structural model. The rhodopsin-arrestin crystal structure solved with SFX represents the first near-atomic resolution structure of a GPCR-arrestin complex, provides structural insights into understanding of arrestin-mediated GPCR signaling, and demonstrates the great potential of this SFX-XFEL technology for accelerating crystal structure determination of challenging proteins and protein complexes. PMID:27070998

  5. Simultaneous Femtosecond X-ray Spectroscopy and Diffraction of Photosystem II at Room Temperature

    PubMed Central

    Kern, Jan; Alonso-Mori, Roberto; Tran, Rosalie; Hattne, Johan; Gildea, Richard J.; Echols, Nathaniel; Glöckner, Carina; Hellmich, Julia; Laksmono, Hartawan; Sierra, Raymond G.; Lassalle-Kaiser, Benedikt; Koroidov, Sergey; Lampe, Alyssa; Han, Guangye; Gul, Sheraz; DiFiore, Dörte; Milathianaki, Despina; Fry, Alan R.; Miahnahri, Alan; Schafer, Donald W.; Messerschmidt, Marc; Seibert, M. Marvin; Koglin, Jason E.; Sokaras, Dimosthenis; Weng, Tsu-Chien; Sellberg, Jonas; Latimer, Matthew J.; Grosse-Kunstleve, Ralf W.; Zwart, Petrus H.; White, William E.; Glatzel, Pieter; Adams, Paul D.; Bogan, Michael J.; Williams, Garth J.; Boutet, Sébastien; Messinger, Johannes; Zouni, Athina; Sauter, Nicholas K.; Yachandra, Vittal K.; Bergmann, Uwe; Yano, Junko

    2013-01-01

    Intense femtosecond X-ray pulses produced at the Linac Coherent Light Source (LCLS) were used for simultaneous X-ray diffraction (XRD) and X-ray emission spectroscopy (XES) of microcrystals of Photosystem II (PS II) at room temperature. This method probes the overall protein structure and the electronic structure of the Mn4CaO5 cluster in the oxygen-evolving complex of PS II. XRD data are presented from both the dark state (S1) and the first illuminated state (S2) of PS II. Our simultaneous XRD/XES study shows that the PS II crystals are intact during our measurements at the LCLS, not only with respect to the structure of PS II, but also with regard to the electronic structure of the highly radiation sensitive Mn4CaO5 cluster, opening new directions for future dynamics studies. PMID:23413188

  6. Optimizing Monocapillary Optics for Synchrotron X-ray Diffraction, Fluorescence Imaging, and Spectroscopy Applications

    SciTech Connect

    Bilderback, Donald H.; Kazimirov, Alexander; Gillilan, Richard; Cornaby, Sterling; Woll, Arthur; Zha, Chang-Sheng; Huang Rong

    2007-01-19

    A number of synchrotron x-ray applications such as powder diffraction in diamond anvil cells, microbeam protein crystallography, x-ray fluorescence imaging, etc. can benefit from using hollow glass monocapillary optics to improve the flux per square micron on a sample. We currently draw glass tubing into the desired elliptical shape so that only one-bounce under total reflection conditions is needed to bring the x-ray beam to a focus at a 25 to 50 mm distance beyond the capillary tip. For modest focal spot sizes of 10 to 20 microns, we can increase the intensity per square micron by factors of 10 to 1000. We show some of the results obtained at CHESS and Hasylab with capillaries focusing 5 to 40 keV radiation, their properties, and how even better the experimental results could be if more ideal capillaries were fabricated in the future.

  7. Optimizing Monocapillary Optics for Synchrotron X-ray Diffraction, Fluorescence Imaging, and Spectroscopy Applications

    NASA Astrophysics Data System (ADS)

    Bilderback, Donald H.; Kazimirov, Alexander; Gillilan, Richard; Cornaby, Sterling; Woll, Arthur; Zha, Chang-Sheng; Huang, Rong

    2007-01-01

    A number of synchrotron x-ray applications such as powder diffraction in diamond anvil cells, microbeam protein crystallography, x-ray fluorescence imaging, etc. can benefit from using hollow glass monocapillary optics to improve the flux per square micron on a sample. We currently draw glass tubing into the desired elliptical shape so that only one-bounce under total reflection conditions is needed to bring the x-ray beam to a focus at a 25 to 50 mm distance beyond the capillary tip. For modest focal spot sizes of 10 to 20 microns, we can increase the intensity per square micron by factors of 10 to 1000. We show some of the results obtained at CHESS and Hasylab with capillaries focusing 5 to 40 keV radiation, their properties, and how even better the experimental results could be if more ideal capillaries were fabricated in the future.

  8. Serial femtosecond X-ray diffraction of 30S ribosomal subunit microcrystals in liquid suspension at ambient temperature using an X-ray free-electron laser

    PubMed Central

    Demirci, Hasan; Sierra, Raymond G.; Laksmono, Hartawan; Shoeman, Robert L.; Botha, Sabine; Barends, Thomas R. M.; Nass, Karol; Schlichting, Ilme; Doak, R. Bruce; Gati, Cornelius; Williams, Garth J.; Boutet, Sébastien; Messerschmidt, Marc; Jogl, Gerwald; Dahlberg, Albert E.; Gregory, Steven T.; Bogan, Michael J.

    2013-01-01

    High-resolution ribosome structures determined by X-ray crystallography have provided important insights into the mechanism of translation. Such studies have thus far relied on large ribosome crystals kept at cryogenic temperatures to reduce radiation damage. Here, the application of serial femtosecond X-ray crystallography (SFX) using an X-ray free-electron laser (XFEL) to obtain diffraction data from ribosome microcrystals in liquid suspension at ambient temperature is described. 30S ribosomal subunit microcrystals diffracted to beyond 6 Å resolution, demonstrating the feasibility of using SFX for ribosome structural studies. The ability to collect diffraction data at near-physiological temperatures promises to provide fundamental insights into the structural dynamics of the ribosome and its functional complexes. PMID:23989164

  9. Emission lines from X-ray-heated accretion disks in low-mass X-ray binaries

    NASA Technical Reports Server (NTRS)

    Ko, Yuan-Kuen; Kallman, Timothy R.

    1994-01-01

    We investigate the structure of accretion disks illuminated by X-rays from a central compact object in a binary system. X-rays can photoionize the upper atmosphere of the disk and form an accretion disk corona (ADC) where emission lines can form. We construct a model to calculate the vertical structure and the emission spectrum of the ADC with parameters appropriate to low-mass X-ray binaries. These models are made by nonlocal thermodynamic equilibrium calculations of ion and level populations and include a large number of atomic processes for 10 cosmically abundant elements. Transfer of radiation is treated by using the escape probability formalism. The vertical temperature profile of the ADC consists of a Compton-heated region and a mid-T zone where the temperature is approximately 10(exp 6) K. A thermal instability occurs close to the disk photosphere and causes the temperature of the ADC to drop abruptly from 10(exp 6) K to several times 10(exp 4) K. The emission spectrum in the optical, ultraviolet, extreme ultraviolet, and X-ray range is discussed and compared with the observations.

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

    SciTech Connect

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

    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.

  11. Direct Modeling of X-Ray Diffraction Pattern from Contracting Skeletal Muscle

    PubMed Central

    Koubassova, Natalia A.; Bershitsky, Sergey Y.; Ferenczi, Michael A.; Tsaturyan, Andrey K.

    2008-01-01

    A direct modeling approach was used to quantitatively interpret the two-dimensional x-ray diffraction patterns obtained from contracting mammalian skeletal muscle. The dependence of the calculated layer line intensities on the number of myosin heads bound to the thin filaments, on the conformation of these heads and on their mode of attachment to actin, was studied systematically. Results of modeling are compared to experimental data collected from permeabilized fibers from rabbit skeletal muscle contracting at 5°C and 30°C and developing low and high isometric tension, respectively. The results of the modeling show that: i), the intensity of the first actin layer line is independent of the tilt of the light chain domains of myosin heads and can be used as a measure of the fraction of myosin heads stereospecifically attached to actin; ii), during isometric contraction at near physiological temperature, the fraction of these heads is ∼40% and the light chain domains of the majority of them are more perpendicular to the filament axis than in rigor; and iii), at low temperature, when isometric tension is low, a majority of the attached myosin heads are bound to actin nonstereospecifically whereas at high temperature and tension they are bound stereospecifically. PMID:18539638

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

    PubMed

    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. PMID:21139221

  13. Apparatus for X-ray diffraction microscopy and tomography of cryo specimens

    DOE PAGESBeta

    Beetz, T.; Howells, M. R.; Jacobsen, C.; Kao, C. -C.; Kirz, J.; Lima, E.; Mentes, T. O.; Miao, H.; Sanchez-Hanke, C.; Sayre, D.; et al

    2005-03-14

    An apparatus for diffraction microscopy of biological and materials science specimens is described. In this system, a coherent soft X-ray beam is selected with a pinhole, and the illuminated specimen is followed by an adjustable beamstop and CCD camera to record diffraction data from non-crystalline specimens. In addition, a Fresnel zone plate can be inserted to allow for direct imaging. The system makes use of a cryogenic specimen holder with cryotransfer capabilities to allow frozen hydrated specimens to be loaded. The specimen can be tilted over a range of ± 80 ° degrees for three-dimensional imaging; this is done bymore » computer-controlled motors, enabling automated alignment of the specimen through a tilt series. The system is now in use for experiments in soft X-ray diffraction microscopy.« less

  14. Transient x-ray diffraction with simultaneous imaging under high strain-rate loading

    SciTech Connect

    Fan, D.; E, J. C.; Zhao, F.; Luo, S. N.; Lu, L.; Li, B.; Qi, M. L.; Sun, T.; Fezzaa, K.; Chen, W.

    2014-11-15

    Real time, in situ, multiframe, diffraction, and imaging measurements on bulk samples under high and ultrahigh strain-rate loading are highly desirable for micro- and mesoscale sciences. We present an experimental demonstration of multiframe transient x-ray diffraction (TXD) along with simultaneous imaging under high strain-rate loading at the Advanced Photon Source beamline 32ID. The feasibility study utilizes high strain-rate Hopkinson bar loading on a Mg alloy. The exposure time in TXD is 2–3 μs, and the frame interval is 26.7–62.5 μs. Various dynamic deformation mechanisms are revealed by TXD, including lattice expansion or compression, crystal plasticity, grain or lattice rotation, and likely grain refinement, as well as considerable anisotropy in deformation. Dynamic strain fields are mapped via x-ray digital image correlation, and are consistent with the diffraction measurements and loading histories.

  15. Synchrotron X-Ray Reciprocal Space Mapping, Topography and Diffraction Resolution Studies of Macromolecular Crystal Quality

    NASA Technical Reports Server (NTRS)

    Boggon, T. J.; Helliwell, J. R.; Judge, Russell A.; Siddons, D. P.; Snell, Edward H.; Stojanoff, V.

    2000-01-01

    A comprehensive study of microgravity and ground grown chicken egg white lysozyme crystals is presented using synchrotron X-ray reciprocal space mapping, topography techniques and diffraction resolution. Microgravity crystals displayed, on average, reduced intrinsic mosaicities but no differences in terms of stress over their earth grown counterparts. Topographic analysis revealed that in the microgravity case the majority of the crystal was contributing to the peak of the reflection at the appropriate Bragg angle. In the earth case at the diffraction peak only a small volume of the crystal contributed to the intensity. The techniques prove to be highly complementary with the reciprocal space mapping providing a quantitative measure of the crystal mosaicity and stress (or variation in lattice spacing) and topography providing a qualitative overall assessment of the crystal in terms of its X-ray diffraction properties. Structural data collection was also carried out both at the synchrotron and in the laboratory.

  16. Apparatus for X-ray diffraction microscopy and tomography of cryo specimens

    SciTech Connect

    Beetz, T.; Howells, M. R.; Jacobsen, C.; Kao, C. -C.; Kirz, J.; Lima, E.; Mentes, T. O.; Miao, H.; Sanchez-Hanke, C.; Sayre, D.; Shapiro, D.

    2005-03-14

    An apparatus for diffraction microscopy of biological and materials science specimens is described. In this system, a coherent soft X-ray beam is selected with a pinhole, and the illuminated specimen is followed by an adjustable beamstop and CCD camera to record diffraction data from non-crystalline specimens. In addition, a Fresnel zone plate can be inserted to allow for direct imaging. The system makes use of a cryogenic specimen holder with cryotransfer capabilities to allow frozen hydrated specimens to be loaded. The specimen can be tilted over a range of ± 80 ° degrees for three-dimensional imaging; this is done by computer-controlled motors, enabling automated alignment of the specimen through a tilt series. The system is now in use for experiments in soft X-ray diffraction microscopy.

  17. Single-particle structure determination by correlations of snapshot X-ray diffraction patterns.

    PubMed

    Starodub, D; Aquila, A; Bajt, S; Barthelmess, M; Barty, A; Bostedt, C; Bozek, J D; Coppola, N; Doak, R B; Epp, S W; Erk, B; Foucar, L; Gumprecht, L; Hampton, C Y; Hartmann, A; Hartmann, R; Holl, P; Kassemeyer, S; Kimmel, N; Laksmono, H; Liang, M; Loh, N D; Lomb, L; Martin, A V; Nass, K; Reich, C; Rolles, D; Rudek, B; Rudenko, A; Schulz, J; Shoeman, R L; Sierra, R G; Soltau, H; Steinbrener, J; Stellato, F; Stern, S; Weidenspointner, G; Frank, M; Ullrich, J; Strüder, L; Schlichting, I; Chapman, H N; Spence, J C H; Bogan, M J

    2012-01-01

    Diffractive imaging with free-electron lasers allows structure determination from ensembles of weakly scattering identical nanoparticles. The ultra-short, ultra-bright X-ray pulses provide snapshots of the randomly oriented particles frozen in time, and terminate before the onset of structural damage. As signal strength diminishes for small particles, the synthesis of a three-dimensional diffraction volume requires simultaneous involvement of all data. Here we report the first application of a three-dimensional spatial frequency correlation analysis to carry out this synthesis from noisy single-particle femtosecond X-ray diffraction patterns of nearly identical samples in random and unknown orientations, collected at the Linac Coherent Light Source. Our demonstration uses unsupported test particles created via aerosol self-assembly, and composed of two polystyrene spheres of equal diameter. The correlation analysis avoids the need for orientation determination entirely. This method may be applied to the structural determination of biological macromolecules in solution. PMID:23232406

  18. Image observation of diffraction spots using FZP and coherent X-ray beam

    SciTech Connect

    Suzuki, Takuya; Yoshizuka, Kazuharu; Takano, Hidekazu; Takeuchi, Akihisa; Uesugi, Kentaro; Suzuki, Yoshio

    2004-05-12

    New small angle X-ray dispersion speckle method by the condensing optical system using FZP (Fresnel zone plate) was performed. And single crystal diffraction spot image was observed using this optical system. High photon flux with the FZP of 100-micron-diameter is obtained than that with a 5-micron-diameter pinhole. S/N ratio of data improved and measurement time also became short. The minimum beam size focused with the FZP was 0.25 {mu}m. The speckle image resulting from the non-ordering structure and periodic structure of 10nm order is successfully observed. This optical system was applicable also to diffraction spot image observation. We show a possibility that the information of the periodic and/or random structural analysis with sub-{mu}m order which were unsuitable with the conventional single crystal x-ray diffraction analysis.

  19. Transient x-ray diffraction with simultaneous imaging under high strain-rate loading

    NASA Astrophysics Data System (ADS)

    Fan, D.; Lu, L.; Li, B.; Qi, M. L.; E, J. C.; Zhao, F.; Sun, T.; Fezzaa, K.; Chen, W.; Luo, S. N.

    2014-11-01

    Real time, in situ, multiframe, diffraction, and imaging measurements on bulk samples under high and ultrahigh strain-rate loading are highly desirable for micro- and mesoscale sciences. We present an experimental demonstration of multiframe transient x-ray diffraction (TXD) along with simultaneous imaging under high strain-rate loading at the Advanced Photon Source beamline 32ID. The feasibility study utilizes high strain-rate Hopkinson bar loading on a Mg alloy. The exposure time in TXD is 2-3 μs, and the frame interval is 26.7-62.5 μs. Various dynamic deformation mechanisms are revealed by TXD, including lattice expansion or compression, crystal plasticity, grain or lattice rotation, and likely grain refinement, as well as considerable anisotropy in deformation. Dynamic strain fields are mapped via x-ray digital image correlation, and are consistent with the diffraction measurements and loading histories.

  20. High-pressure X-ray diffraction studies of potassium chlorate

    SciTech Connect

    Pravica, Michael; Bai, Ligang; Bhattacharya, Neelanjan

    2012-03-15

    Two static high-pressure X-ray diffraction (XRD) studies of potassium chlorate have been performed at pressures of up to {approx}14.3 GPa in a diamond anvil cell at ambient temperature using the 16 ID-B undulator beamline at the Advanced Photon Source for the X-ray source. The first experiment was conducted to ascertain decomposition rates of potassium chlorate as a function of pressure. Below 2 GPa, the sample was observed to decompose rapidly in the presence of the X-ray beam and release oxygen. Above 2 GPa (near the phase I phase II transition), the decomposition rate dramatically slowed so that good quality XRD patterns could be acquired. This suggests a phase-dependent decomposition rate. In the second study, X-ray diffraction spectra were collected at pressures from 2 to 14.3 GPa by aligning virgin portions of the sample into the focused X-ray beam at each pressure. The results suggest the co-existence of mixed monoclinic (I) and rhombohedral (II) phases of potassium chlorate near 2 GPa. At pressures beyond 4 GPa, the XRD patterns show a very good fit to KClO{sub 3} in the rhombohedral phase with space group R3m, in agreement with earlier studies. No further phase transitions were observed with pressure. Decompression of the sample to ambient pressure indicated mixed phases I and II coupled with a small amount of synchrotron X-ray-induced decomposition product. The equation of state within this pressure regime has been determined.

  1. Limit of Detection in X-ray Diffraction Measurements of Tissue Equivalent Samples

    NASA Astrophysics Data System (ADS)

    Zheng, Y.; Vassiljev, N.; Konstantinidis, A.; Griffiths, J.; Speller, R.

    2015-09-01

    There is a suggestion of a new approach to mammography whereby following a conventional mammogram, the radiologist could interrogate suspicious regions using X-ray diffraction whilst the patient is still present and to establish the true extent of disease. A starting point for this work is to quantify the minimum detectable amount of breast cancer within a realistic thickness phantom. Perspex has a similar diffraction pattern to healthy breast tissue whilst water is similar to breast tumour, hence these two materials are used as tissue equivalent test objects for X-ray diffraction measurements. The preliminary results show linear agreement between the ratio of Perspex to water and the ratio of the diffraction peak intensities at 0.7 nm-1 and 1.5 nm-1. The minimum detectable limit for a component of the two ‘tissue’ mix was found to be 4.1%. This suggests that X-ray diffraction can be used to quantify tissue like mixtures down to the 4.1% / 95.9% mix level and hence has a strong potential for delineating the extent of infiltration disease.

  2. Dynamical X-ray Diffraction from In x Ga1- x As Heterostructures with Dislocations

    NASA Astrophysics Data System (ADS)

    Rago, P. B.; Ayers, J. E.

    2013-08-01

    High-resolution x-ray diffraction is an important nondestructive tool for structural characterization of semiconductor heterostructures, and the diffraction intensity profiles contain information on the depth profiles of strain, composition, and defect densities in device heterostructures. Much of this information remains inaccessible because the lack of phase information prevents direct inversion of the rocking curves. The current practice is to use dynamical simulations in conjunction with a curve-fitting procedure to indirectly extract the profiles of strain and composition, but such dynamical simulations have been based on perfect, dislocation-free laminar crystals, which renders the analysis inapplicable to highly mismatched structures containing dislocation densities greater than about 106 cm-2. In this work we present a dynamical model for Bragg x-ray diffraction in semiconductor device structures with nonuniform composition, strain, and dislocation density, which is based on the Takagi-Taupin equation for distorted crystals and accounts for the diffuse scattering arising from the strain mosaicity and angular mosaicity associated with dislocations. We show theoretically that the x-ray diffraction profiles from In x Ga1- x As/GaAs (001) heterostructures are strongly affected by the depth distribution of the dislocation density as well as the composition and strain, so that in principle all three distributions may be obtained by the analysis of the measured diffraction profiles.

  3. X-Ray Continua of Broad Absorption Line Quasars

    NASA Technical Reports Server (NTRS)

    Mathur, S.

    1999-01-01

    The targets for this program, PG1416-129 and LBQS 2212-1759 were known to be Broad Absorption Line Quasars (BALQSOs). BALQSOs are highly absorbed in soft X-rays. Good high energy response of Rossi-XTE made them ideal targets for observation. We observed LBQS 2212-1759 with PCA. We have now analyzed the data and found that the source was not detected. Since our target was expected to be faint, reliable estimate of background was very important. With the release of new FTOOLS (version 4.1) we were able to do so. We also analyzed a well known bright object and verified our results with the published data. This gave us confidence in the non-detection of our target LBQS 2212-1759. We are currently investigating the implications of this non-detection. Due to some scheduling problems, our second target PG1416-129 was not observed in A01. It was observed on 06/26/98. This target was detected with RXTE. We are now working on the spectral analysis with XSPEC.

  4. Modeling X-ray emission line profiles from massive star winds - A review

    NASA Astrophysics Data System (ADS)

    Ignace, Richard

    2016-09-01

    The Chandra and XMM-Newton X-ray telescopes have led to numerous advances in the study and understanding of astrophysical X-ray sources. Particularly important has been the much increased spectral resolution of modern X-ray instrumentation. Wind-broadened emission lines have been spectroscopically resolved for many massive stars. This contribution reviews approaches to the modeling of X-ray emission line profile shapes from single stars, including smooth winds, winds with clumping, optically thin versus thick lines, and the effect of a radius-dependent photoabsorption coefficient.

  5. In-line phase-contrast imaging based on Tsinghua Thomson scattering x-ray source.

    PubMed

    Zhang, Zhen; Du, Yingchao; Yan, Lixin; Hua, Jianfei; Yang, Jin; Xiao, Yongshun; Huang, Wenhui; Chen, Huaibi; Tang, Chuanxiang

    2014-08-01

    Thomson scattering x-ray sources can produce ultrashort, energy tunable x-ray pulses characterized by high brightness, quasi-monochromatic, and high spatial coherence, which make it an ideal source for in-line phase-contrast imaging. We demonstrate the capacity of in-line phase-contrast imaging based on Tsinghua Thomson scattering X-ray source. Clear edge enhancement effect has been observed in the experiment. PMID:25173262

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

    SciTech Connect

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

    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.

  7. Self-terminating diffraction gates femtosecond X-ray nanocrystallography measurements

    PubMed Central

    Barty, Anton; Caleman, Carl; Aquila, Andrew; Timneanu, Nicusor; Lomb, Lukas; White, Thomas A.; Andreasson, Jakob; Arnlund, David; Bajt, Saša; Barends, Thomas R. M.; Barthelmess, Miriam; Bogan, Michael J.; Bostedt, Christoph; Bozek, John D.; Coffee, Ryan; Coppola, Nicola; Davidsson, Jan; DePonte, Daniel P.; Doak, R. Bruce; Ekeberg, Tomas; Elser, Veit; Epp, Sascha W.; Erk, Benjamin; Fleckenstein, Holger; Foucar, Lutz; Fromme, Petra; Graafsma, Heinz; Gumprecht, Lars; Hajdu, Janos; Hampton, Christina Y.; Hartmann, Robert; Hartmann, Andreas; Hauser, Günter; Hirsemann, Helmut; Holl, Peter; Hunter, Mark S.; Johansson, Linda; Kassemeyer, Stephan; Kimmel, Nils; Kirian, Richard A.; Liang, Mengning; Maia, Filipe R. N. C.; Malmerberg, Erik; Marchesini, Stefano; Martin, Andrew V.; Nass, Karol; Neutze, Richard; Reich, Christian; Rolles, Daniel; Rudek, Benedikt; Rudenko, Artem; Scott, Howard; Schlichting, Ilme; Schulz, Joachim; Seibert, M. Marvin; Shoeman, Robert L.; Sierra, Raymond G.; Soltau, Heike; Spence, John C. H.; Stellato, Francesco; Stern, Stephan; Strüder, Lothar; Ullrich, Joachim; Wang, X.; Weidenspointner, Georg; Weierstall, Uwe; Wunderer, Cornelia B.; Chapman, Henry N.

    2013-01-01

    X-ray free-electron lasers have enabled new approaches to the structural determination of protein crystals that are too small or radiation-sensitive for conventional analysis1. For sufficiently short pulses, diffraction is collected before significant changes occur to the sample, and it has been predicted that pulses as short as 10 fs may be required to acquire atomic-resolution structural information1–4. Here, we describe a mechanism unique to ultrafast, ultra-intense X-ray experiments that allows structural information to be collected from crystalline samples using high radiation doses without the requirement for the pulse to terminate before the onset of sample damage. Instead, the diffracted X-rays are gated by a rapid loss of crystalline periodicity, producing apparent pulse lengths significantly shorter than the duration of the incident pulse. The shortest apparent pulse lengths occur at the highest resolution, and our measurements indicate that current X-ray free-electron laser technology5 should enable structural determination from submicrometre protein crystals with atomic resolution. PMID:24078834

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

    PubMed Central

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

    2014-01-01

    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. PMID:24914153

  9. Self-terminating diffraction gates femtosecond X-ray nanocrystallography measurements.

    PubMed

    Barty, Anton; Caleman, Carl; Aquila, Andrew; Timneanu, Nicusor; Lomb, Lukas; White, Thomas A; Andreasson, Jakob; Arnlund, David; Bajt, Saša; Barends, Thomas R M; Barthelmess, Miriam; Bogan, Michael J; Bostedt, Christoph; Bozek, John D; Coffee, Ryan; Coppola, Nicola; Davidsson, Jan; Deponte, Daniel P; Doak, R Bruce; Ekeberg, Tomas; Elser, Veit; Epp, Sascha W; Erk, Benjamin; Fleckenstein, Holger; Foucar, Lutz; Fromme, Petra; Graafsma, Heinz; Gumprecht, Lars; Hajdu, Janos; Hampton, Christina Y; Hartmann, Robert; Hartmann, Andreas; Hauser, Günter; Hirsemann, Helmut; Holl, Peter; Hunter, Mark S; Johansson, Linda; Kassemeyer, Stephan; Kimmel, Nils; Kirian, Richard A; Liang, Mengning; Maia, Filipe R N C; Malmerberg, Erik; Marchesini, Stefano; Martin, Andrew V; Nass, Karol; Neutze, Richard; Reich, Christian; Rolles, Daniel; Rudek, Benedikt; Rudenko, Artem; Scott, Howard; Schlichting, Ilme; Schulz, Joachim; Seibert, M Marvin; Shoeman, Robert L; Sierra, Raymond G; Soltau, Heike; Spence, John C H; Stellato, Francesco; Stern, Stephan; Strüder, Lothar; Ullrich, Joachim; Wang, X; Weidenspointner, Georg; Weierstall, Uwe; Wunderer, Cornelia B; Chapman, Henry N

    2012-01-01

    X-ray free-electron lasers have enabled new approaches to the structural determination of protein crystals that are too small or radiation-sensitive for conventional analysis(1). For sufficiently short pulses, diffraction is collected before significant changes occur to the sample, and it has been predicted that pulses as short as 10 fs may be required to acquire atomic-resolution structural information(1-4). Here, we describe a mechanism unique to ultrafast, ultra-intense X-ray experiments that allows structural information to be collected from crystalline samples using high radiation doses without the requirement for the pulse to terminate before the onset of sample damage. Instead, the diffracted X-rays are gated by a rapid loss of crystalline periodicity, producing apparent pulse lengths significantly shorter than the duration of the incident pulse. The shortest apparent pulse lengths occur at the highest resolution, and our measurements indicate that current X-ray free-electron laser technology(5) should enable structural determination from submicrometre protein crystals with atomic resolution. PMID:24078834

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

    PubMed

    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. PMID:24914153

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

    NASA Astrophysics Data System (ADS)

    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.

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

    NASA Technical Reports Server (NTRS)

    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.

  13. X-ray diffraction analysis of titanium tritide film during 1600 days

    NASA Astrophysics Data System (ADS)

    Xiaosong, Zhou; Xinggui, Long; Lin, Zhang; Shuming, Peng; Shunzhong, Luo

    2010-01-01

    The generation and accumulation of 3He by tritium decay modified the physical and chemical properties of tritides. Here the evolution of lattice defects in long-aged titanium tritide films is investigated by X-ray diffraction and changes in the positions, intensities and line shapes of diffraction peaks have been determined over a period of about 1600 days (>4 years). Texture effects are also observed by biased intensities in standard θ-2θ scans. The results show that the TiT1.5 film keeps an fcc structure during 1600 days and reveals an hkl-dependent unit-cell expansion and line width broadening which are interpreted in terms of isolated tetrahedral interstitial 3He atoms and isolated bubble growth models by dislocation loop-punching or dislocation dipole expansion combined with Krivoglaz theory. In the first 12 days of aging, isolated tetrahedral interstitial 3He atoms or 3He clusters are formed, then interstitial 3He atoms diffuse into (1 1 1) planes and precipitate into clusters. The spontaneous formation of Frenkel pairs, the self-interstitial atoms produced are built into dislocations resulting in formation platelet bubbles and dislocation dipoles between 12 and 27 days. Above 27 days, multiple stages of 3He bubbles growth appear: (1) between 27 and 85 days platelet helium bubbles growth by dislocation dipoles expansion, (2) between 85 and 231 days the transition from platelet bubbles to sphere bubbles by loop emission, (3) after 231 days sphere bubbles growth by dislocation loop-punching and probably formation of sub-grain boundaries by dislocation rearrangement.

  14. Transient electron density maps of ionic materials from femtosecond x-ray powder diffraction

    NASA Astrophysics Data System (ADS)

    Elsaesser, Thomas

    2014-05-01

    X-ray diffraction represents a key method for spatially resolving electron distributions in crystalline materials. So far, electron density maps have been derived from stationary diffraction patterns, providing detailed insight into the equilibrium charge distribution and crystal geometry. Functional processes in condensed matter are frequently connected with nonequilibrium excitations resulting in atomic motions and charge relocations on ultrashort time scales. Transient structures are resolved in space and time by novel x-ray diffraction methods with a femtosecond time resolution, giving access to the driving mechanisms and underlying interactions. In this talk, new results are presented on transient electron distributions of ionic materials mapped with the help of femtosecond x-ray powder diffraction. Experiments are based on a pump-probe approach in which an optical pulse initiates structural dynamics and a hard x-ray pulse from a synchronized laser-driven plasma source is diffracted from the excited powder sample. Such measurements reveal the interplay of lattice and charge motions in the photoexcited prototype material KDP (KH2PO4) which occur on distinctly different length scales. As a second topic, electron relocations induced by strong external optical fields will be discussed. This interaction mechanism allows for generating coherent superpositions of valence and conduction band quantum states and inducing fully reversible charge dynamics. While the materials LiBH4 and NaBH4 display electron relocations from the (BH4)- ions to the neighboring Li+ and Na+ ions, LiH exhibits an electron transfer from Li to H. The latter is a manifestation of electron correlations and in agreement with theoretical calculations.

  15. Simulations of in situ x-ray diffraction from uniaxially compressed highly textured polycrystalline targets

    SciTech Connect

    McGonegle, David Wark, Justin S.; Higginbotham, Andrew; Milathianaki, Despina; Remington, Bruce A.

    2015-08-14

    A growing number of shock compression experiments, especially those involving laser compression, are taking advantage of in situ x-ray diffraction as a tool to interrogate structure and microstructure evolution. Although these experiments are becoming increasingly sophisticated, there has been little work on exploiting the textured nature of polycrystalline targets to gain information on sample response. Here, we describe how to generate simulated x-ray diffraction patterns from materials with an arbitrary texture function subject to a general deformation gradient. We will present simulations of Debye-Scherrer x-ray diffraction from highly textured polycrystalline targets that have been subjected to uniaxial compression, as may occur under planar shock conditions. In particular, we study samples with a fibre texture, and find that the azimuthal dependence of the diffraction patterns contains information that, in principle, affords discrimination between a number of similar shock-deformation mechanisms. For certain cases, we compare our method with results obtained by taking the Fourier transform of the atomic positions calculated by classical molecular dynamics simulations. Illustrative results are presented for the shock-induced α–ϵ phase transition in iron, the α–ω transition in titanium and deformation due to twinning in tantalum that is initially preferentially textured along [001] and [011]. The simulations are relevant to experiments that can now be performed using 4th generation light sources, where single-shot x-ray diffraction patterns from crystals compressed via laser-ablation can be obtained on timescales shorter than a phonon period.

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

    SciTech Connect

    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

    2015-04-30

    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.

  17. The Scherrer equation and the dynamical theory of X-ray diffraction.

    PubMed

    Muniz, Francisco Tiago Leitão; Miranda, Marcus Aurélio Ribeiro; Morilla Dos Santos, Cássio; Sasaki, José Marcos

    2016-05-01

    The Scherrer equation is a widely used tool to determine the crystallite size of polycrystalline samples. However, it is not clear if one can apply it to large crystallite sizes because its derivation is based on the kinematical theory of X-ray diffraction. For large and perfect crystals, it is more appropriate to use the dynamical theory of X-ray diffraction. Because of the appearance of polycrystalline materials with a high degree of crystalline perfection and large sizes, it is the authors' belief that it is important to establish the crystallite size limit for which the Scherrer equation can be applied. In this work, the diffraction peak profiles are calculated using the dynamical theory of X-ray diffraction for several Bragg reflections and crystallite sizes for Si, LaB6 and CeO2. The full width at half-maximum is then extracted and the crystallite size is computed using the Scherrer equation. It is shown that for crystals with linear absorption coefficients below 2117.3 cm(-1) the Scherrer equation is valid for crystallites with sizes up to 600 nm. It is also shown that as the size increases only the peaks at higher 2θ angles give good results, and if one uses peaks with 2θ > 60° the limit for use of the Scherrer equation would go up to 1 µm. PMID:27126115

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

    PubMed

    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. PMID:26798805

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

    SciTech Connect

    Fabrizi, Federica; Thomas, Pamela A.; Nisbet, Gareth; Collins, Stephen P.

    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)

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

    DOE PAGESBeta

    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; et al

    2015-04-30

    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, femtosecondmore » 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.« less

  1. Determination of line profiles on nano-structured surfaces using EUV and x-ray scattering

    NASA Astrophysics Data System (ADS)

    Soltwisch, Victor; Wernecke, Jan; Haase, Anton; Probst, Jürgen; Schoengen, Max; Krumrey, Michael; Scholze, Frank; Pomplun, Jan; Burger, Sven

    2014-09-01

    Non-imaging techniques like X-ray scattering are supposed to play an important role in the further development of CD metrology for the semiconductor industry. Grazing Incidence Small Angle X-ray Scattering (GISAXS) provides directly assessable information on structure roughness and long-range periodic perturbations. The disadvantage of the method is the large footprint of the X-ray beam on the sample due to the extremely shallow angle of incidence. This can be overcome by using wavelengths in the extreme ultraviolet (EUV) spectral range, EUV small angle scattering (EUVSAS), which allows for much steeper angles of incidence but preserves the range of momentum transfer that can be observed. Generally, the potentially higher momentum transfer at shorter wavelengths is counterbalanced by decreasing diffraction efficiency. This results in a practical limit of about 10 nm pitch for which it is possible to observe at least the +/- 1st diffraction orders with reasonable efficiency. At the Physikalisch-Technische Bundesanstalt (PTB), the available photon energy range extends from 50 eV up to 10 keV at two adjacent beamlines. PTB commissioned a new versatile Ellipso-Scatterometer which is capable of measuring 6" square substrates in a clean, hydrocarbon-free environment with full flexibility regarding the direction of the incident light polarization. The reconstruction of line profiles using a geometrical model with six free parameters, based on a finite element method (FEM) Maxwell solver and a particle swarm based least-squares optimization yielded consistent results for EUV-SAS and GISAXS. In this contribution we present scatterometry data for line gratings and consistent reconstruction results of the line geometry for EUV-SAS and GISAXS.

  2. X-ray Diffraction Studies of the Thick Filament in Permeabilized Myocardium from Rabbit

    SciTech Connect

    Xu,S.; Martyn, D.; Zaman, J.; Yu, L.

    2007-01-01

    Low angle x-ray diffraction patterns from relaxed permeabilized rabbit cardiac trabeculae and psoas muscle fibers were compared. Temperature was varied from 25{sup o}C to 5{sup o}C at 200 mM and 50 mM ionic strengths ({mu}), respectively. Effects of temperature and {mu} on the intensities of the myosin layer lines (MLL), the equatorial intensity ratio I{sub 1,1}/I{sub 1,0}, and the spacing of the filament lattice are similar in both muscles. At 25{sup o}C, particularly at {mu} = 50 mM, the x-ray patterns exhibited up to six orders of MLL and sharp meridional reflections, signifying that myosin heads (cross-bridges) are distributed in a well-ordered helical array. Decreasing temperature reduced MLL intensities but increased I{sub 1,1}/I{sub 1,0}. Decreases in the MLL intensities indicate increasing disorder in the distribution of cross-bridges on the thick filaments surface. In the skeletal muscle, order/disorder is directly correlated with the hydrolysis equilibrium of ATP by myosin, [M.ADP.P{sub i}]/[M.ATP]. Similar effects of temperature on MLL and similar biochemical ATP hydrolysis pathway found in both types of muscles suggest that the order/disorder states of cardiac cross-bridges may well be correlated with the same biochemical and structural states. This implies that in relaxed cardiac muscle under physiological conditions, the unattached cross-bridges are largely in the M.ADP.P{sub i} state and with the lowering of the temperature, the equilibrium is increasingly in favor of [M.ATP] and [A.M.ATP]. There appear to be some differences in the diffraction patterns from the two muscles, however. Mainly, in the cardiac muscle, the MLL are weaker, the I{sub 1,1}/I{sub 1,0} ratio tends to be higher, and the lattice spacing D{sub 10}, larger. These differences are consistent with the idea that under a wide range of conditions, a greater fraction of cross-bridges is weakly bound to actin in the myocardium.

  3. X-ray Diffraction Studies of the Thick Filament in Permeabilized Myocardium from Rabbit

    SciTech Connect

    Xu,S.; Martyn, D.; Zaman, J.; Yu, L.

    2006-01-01

    Low angle x-ray diffraction patterns from relaxed permeabilized rabbit cardiac trabeculae and psoas muscle fibers were compared. Temperature was varied from 25{sup o}C to 5{sup o}C at 200 mM and 50 mM ionic strengths ({mu}), respectively. Effects of temperature and {mu} on the intensities of the myosin layer lines (MLL), the equatorial intensity ratio I{sub 1,1}/I{sub 1,0}, and the spacing of the filament lattice are similar in both muscles. At 25{sup o}C, particularly at {mu} = 50 mM, the x-ray patterns exhibited up to six orders of MLL and sharp meridional reflections, signifying that myosin heads (cross-bridges) are distributed in a well-ordered helical array. Decreasing temperature reduced MLL intensities but increased I{sub 1,1}/I{sub 1,0}. Decreases in the MLL intensities indicate increasing disorder in the distribution of cross-bridges on the thick filaments surface. In the skeletal muscle, order/disorder is directly correlated with the hydrolysis equilibrium of ATP by myosin, [M.ADP.P{sub i}]/[M.ATP]. Similar effects of temperature on MLL and similar biochemical ATP hydrolysis pathway found in both types of muscles suggest that the order/disorder states of cardiac cross-bridges may well be correlated with the same biochemical and structural states. This implies that in relaxed cardiac muscle under physiological conditions, the unattached cross-bridges are largely in the M.ADP.P{sub i} state and with the lowering of the temperature, the equilibrium is increasingly in favor of [M.ATP] and [A.M.ATP]. There appear to be some differences in the diffraction patterns from the two muscles, however. Mainly, in the cardiac muscle, the MLL are weaker, the I{sub 1,1}/I{sub 1,0} ratio tends to be higher, and the lattice spacing D{sub 10}, larger. These differences are consistent with the idea that under a wide range of conditions, a greater fraction of cross-bridges is weakly bound to actin in the myocardium.

  4. X-ray diffraction imaging of metal–oxide epitaxial tunnel junctions made by optical lithography: use of focused and unfocused X-ray beams

    PubMed Central

    Mocuta, Cristian; Barbier, Antoine; Stanescu, Stefan; Matzen, Sylvia; Moussy, Jean-Baptiste; Ziegler, Eric

    2013-01-01

    X-ray diffraction techniques are used in imaging mode in order to characterize micrometre-sized objects. The samples used as models are metal–oxide tunnel junctions made by optical lithography, with lateral sizes ranging from 150 µm down to 10 µm and various shapes: discs, squares and rectangles. Two approaches are described and compared, both using diffraction contrast: full-field imaging (topography) and raster imaging (scanning probe) using a micrometre-sized focused X-ray beam. It is shown that the full-field image gives access to macroscopic distortions (e.g. sample bending), while the local distortions, at the micrometre scale (e.g. tilts of the crystalline planes in the vicinity of the junction edges), can be accurately characterized only using focused X-ray beams. These local defects are dependent on the junction shape and larger by one order of magnitude than the macroscopic curvature of the sample. PMID:23412494

  5. Shock Melting of Forsterite by In-Situ X-Ray Diffraction

    NASA Astrophysics Data System (ADS)

    Newman, M.; Kraus, R. G.; Wicks, J. K.; Coppari, F.; Smith, R.; Duffy, T. S.

    2015-12-01

    The equation of state of magnesium silicates at pressures and temperatures near the solid-liquid coexistence curve is important for understanding the thermal evolution and interior structure of rocky planets. Here, we present a series of laser driven shock-melt experiments on single crystal Mg_2SiO_4 forsterite, conducted at the Omega EP laser facility. Particle velocities in the Mg_2SiO_4 samples were measured using a line VISAR and used to infer the thermodynamic state of the shocked samples. In situ X-ray diffraction measurements are used to probe the melting transition and investigate the potential decomposition of Mg_2SiO_4 in to MgO and MgSiO_3 upon melt. This work examines potential kinetic effects of decomposition due to the short time scale of laser-shock experiments. In addition, the thermodynamic data collected in these experiments adds to a limited body of information regarding the equation of state of Mg_2SiO_4, which is the dominant end member composition in Earth's upper mantle. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

  6. High temperature X-ray diffraction, Raman spectroscopy and dielectric studies on yttrium orthochromites

    NASA Astrophysics Data System (ADS)

    Mall, Ashish Kumar; Garg, Ashish; Gupta, Rajeev

    2016-05-01

    The structural, thermal and dielectric properties of YCrO3 ceramic prepared by solid state reaction method have been investigated by a combination of XRD, Raman spectroscopy and permittivity measurement. The X-ray diffraction spectra shows single phase orthorhombically distorted perovskite structure with Pnma symmetry over a wide range of temperature 300K to 1100K. Impedance spectroscopy study on the sample showed that the dielectric constant, tangent loss and ac conductivity with frequency increases on increasing the temperature. Dielectric measurement shows a relaxor like transition at about 460K. Non-Debye type relaxation is observed with activation energy of 0.25 eV extracted from ac conductivity at 11 kHz frequency. We believe that the oxygen ion vacancies play an important role in conduction processes in addition to polaron hopping at higher temperatures. Raman scattering measurements were performed over a wide temperature range from 300K to 600 K. The line width of the modes due to CrO6 bending and in-plane O2 stretching broadens with increasing temperature.

  7. Dimorphism in methylammonium aluminum alum studied by X-ray diffraction and electron paramagnetic resonance

    NASA Astrophysics Data System (ADS)

    Lou, Ssu-Hao; Yu, Jiang-Tsu

    1992-11-01

    We have found a reliable method of growing single-phase methyl-ammonium alum (MASD) crystallising in the infrequently-occurring α alum structure; the presence of the perchlorate ion, ClO 4-, in growth solutions induces the crystallisation of α MASD crystals. Seeding the growth solution with α MASD crystals also induces crystallisation of new α MASD crystals. The X-ray powder diffraction pattern and the EPR spectrum of the Cr 3+ ions doped into α MASD are drastically different from those for the more frequently occuring β MASD. The linewidths of Cr 3+ in α and β MASD show anomalous angular dependence. The inhomogeneous line broadening observed for β MASD could be explained by a random distribution in the orientation of the symmetry axis of the trigonal [ Cr( H2O) 6] 3+ complex. The linewidth anomaly shows a more complicated angular dependence for α MASD; it could be that not only the orientation of the symmetry axis but also the magnitude of the axial crystal field of [ Cr( H2O) 6] 3+ suffer random distributions.

  8. Theoretical study of the properties of X-ray diffraction moiré fringes. I

    SciTech Connect

    Yoshimura, Jun-ichi

    2015-05-14

    A detailed and comprehensive theoretical description of X-ray diffraction moiré fringes for a bicrystal specimen is given on the basis of a calculation by plane-wave dynamical diffraction theory, where the effect of the Pendellösung intensity oscillation on the moiré pattern is explained in detail. A detailed and comprehensive theoretical description of X-ray diffraction moiré fringes for a bicrystal specimen is given on the basis of a calculation by plane-wave dynamical diffraction theory. Firstly, prior to discussing the main subject of the paper, a previous article [Yoshimura (1997 ▸). Acta Cryst. A53, 810–812] on the two-dimensionality of diffraction moiré patterns is restated on a thorough calculation of the moiré interference phase. Then, the properties of moiré fringes derived from the above theory are explained for the case of a plane-wave diffraction image, where the significant effect of Pendellösung intensity oscillation on the moiré pattern when the crystal is strained is described in detail with theoretically simulated moiré images. Although such plane-wave moiré images are not widely observed in a nearly pure form, knowledge of their properties is essential for the understanding of diffraction moiré fringes in general.

  9. In situ x-ray diffraction measurements of the capillary fountain jet produced via ultrasonic atomization

    NASA Astrophysics Data System (ADS)

    Yano, Yohko F.; Douguchi, Junya; Kumagai, Atsushi; Iijima, Takao; Tomida, Yukinobu; Miyamoto, Toshiaki; Matsuura, Kazuo

    2006-11-01

    In situ x-ray diffraction measurements were carried out for investigating the liquid structure in the ultrasonic fountain jet to consider the mechanism of the "ultrasonic ethanol separation" reported by Sato et al. [J. Chem. Phys. 114, 2382 (2001)]. For pure liquids (water and ethanol), it was found that the high frequency ultrasound does not affect the liquid structure microscopically. For the 20mol% ethanol-water mixture, the estimated ethanol mole fraction in the ultrasonic fountain jet by using the position of the main maximum in the x-ray diffraction profile coincided with that in the reservoir. This result suggests that the ethanol separation is not caused by any distorted liquid structure under the ultrasound irradiation and occurs when or after the generation of the liquid droplet mist.

  10. In situ x-ray diffraction measurements of the capillary fountain jet produced via ultrasonic atomization.

    PubMed

    Yano, Yohko F; Douguchi, Junya; Kumagai, Atsushi; Iijima, Takao; Tomida, Yukinobu; Miyamoto, Toshiaki; Matsuura, Kazuo

    2006-11-01

    In situ x-ray diffraction measurements were carried out for investigating the liquid structure in the ultrasonic fountain jet to consider the mechanism of the "ultrasonic ethanol separation" reported by Sato et al. [J. Chem. Phys. 114, 2382 (2001)]. For pure liquids (water and ethanol), it was found that the high frequency ultrasound does not affect the liquid structure microscopically. For the 20 mol % ethanol-water mixture, the estimated ethanol mole fraction in the ultrasonic fountain jet by using the position of the main maximum in the x-ray diffraction profile coincided with that in the reservoir. This result suggests that the ethanol separation is not caused by any distorted liquid structure under the ultrasound irradiation and occurs when or after the generation of the liquid droplet mist. PMID:17100459

  11. TOPICAL REVIEW Quantitative strain analysis of surfaces and interfaces using extremely asymmetric x-ray diffraction

    NASA Astrophysics Data System (ADS)

    Akimoto, Koichi; Emoto, Takashi

    2010-12-01

    Strain can reduce carrier mobility and the reliability of electronic devices and affect the growth mode of thin films and the stability of nanometer-scale crystals. To control lattice strain, a technique for measuring the minute lattice strain at surfaces and interfaces is needed. Recently, an extremely asymmetric x-ray diffraction method has been developed for this purpose. By employing Darwin's dynamical x-ray diffraction theory, quantitative evaluation of strain at surfaces and interfaces becomes possible. In this paper, we review our quantitative strain analysis studies on native SiO2/Si interfaces, reconstructed Si surfaces, Ni/Si(111)-H interfaces, sputtered III-V compound semiconductor surfaces, high-k/Si interfaces, and Au ion-implanted Si.

  12. X-ray and neutron diffraction study of nanocrystalline Ti-Ru-Fe-O compounds

    SciTech Connect

    Blouin, M.; Guay, D.; Huot, J.; Schulz, R.; Swainson, I.P.

    1998-11-01

    The effect of adding oxygen on the structure of nanocrystalline Ti-Ru-Fe compounds obtained by high-energy ball-milling has been studied by X-ray and neutron diffraction using a Rietveld refinement analysis. It is shown that oxygen atoms readily oxidize Ti to form various types of titanium oxides depending on the oxygen content. In each case, a simple cubic structure (cP2-CsCl) is also formed during milling but with a concentration higher than expected on the basis of various reaction schemes. Through a detailed analysis of the neutron and X-ray diffraction peaks, it is shown that the 1a site of the CsCl-type unit cell is depleted from Ti atoms by preferential substitution with Fe. At high oxygen concentration, the alloy is a multiphase material containing Ti{sub 2{minus}x}Ru{sub 1+y}Fe{sub 1+z}, Ti oxides, Ru, and Fe.

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

    SciTech Connect

    Kiyota, Eduardo; Sousa, Sylvia Morais de; Santos, Marcelo Leite dos; Costa Lima, Aline da; Menossi, Marcelo; Yunes, José Andrés; Aparicio, Ricardo

    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.

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

    PubMed Central

    Kriegner, D.; Persson, J.M.; Etzelstorfer, T.; Jacobsson, D.; Wallentin, J.; Wagner, J.B.; Deppert, K.; Borgström, M.T.; Stangl, J.

    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 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 10 μm are available, enables us to investigate compositional 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. PMID:24089580

  15. Method for characterizing mask defects using image reconstruction from X-ray diffraction patterns

    DOEpatents

    Hau-Riege, Stefan Peter

    2007-05-01

    The invention applies techniques for image reconstruction from X-ray diffraction patterns on the three-dimensional imaging of defects in EUVL multilayer films. The reconstructed image gives information about the out-of-plane position and the diffraction strength of the defect. The positional information can be used to select the correct defect repair technique. This invention enables the fabrication of defect-free (since repaired) X-ray Mo--Si multilayer mirrors. Repairing Mo--Si multilayer-film defects on mask blanks is a key for the commercial success of EUVL. It is known that particles are added to the Mo--Si multilayer film during the fabrication process. There is a large effort to reduce this contamination, but results are not sufficient, and defects continue to be a major mask yield limiter. All suggested repair strategies need to know the out-of-plane position of the defects in the multilayer.

  16. Resonant X-ray diffraction in incommensurately modulated crystals. Symmetry consideration of anisotropic anomalous scattering.

    PubMed

    Ovchinnikova; Dmitrienko

    1999-01-01

    Symmetry restrictions on the intensities and polarization properties of main reflections and their satellites are found for incommensurately modulated crystals in the case of anisotropic anomalous X-ray diffraction near absorption edges. It is shown that the modulation becomes a source of additional anisotropy for each resonant scatterer and induces a modulated behaviour of the susceptibility tensor. The four-dimensional approach is used to calculate the set of possible reflections. It is found that additional ('forbidden') reflections may appear both in the system of main reflections and in the system of satellites. The anisotropy also results in complex azimuthal and polarization properties of each reflection. The displacive modulation is discussed in detail. The ATS reflections corresponding to the resonant X-ray diffraction near the K-edge of iron in pyrrhotite-5.5C are considered. PMID:10927227

  17. Equation of state for technetium from X-ray diffraction and first-principle calculations

    NASA Astrophysics Data System (ADS)

    Mast, Daniel S.; Kim, Eunja; Siska, Emily M.; Poineau, Frederic; Czerwinski, Kenneth R.; Lavina, Barbara; Forster, Paul M.

    2016-08-01

    The ambient temperature equation of state (EoS) of technetium metal has been measured by X-ray diffraction. The metal was compressed using a diamond anvil cell and using a 4:1 methanol-ethanol pressure transmitting medium. The maximum pressure achieved, as determined from the gold pressureEquation of state for technetium from X-ray diffraction and first-principle calculations scale, was 67 GPa. The compression data shows that the HCP phase of technetium is stable up to 67 GPa. The compression curve of technetium was also calculated using first-principles total-energy calculations. Utilizing a number of fitting strategies to compare the experimental and theoretical data it is determined that the Vinet equation of state with an ambient isothermal bulk modulus of B0T=288 GPa and a first pressure derivative of B‧=5.9(2) best represent the compression behavior of technetium metal.

  18. Ultrafast lattice response of photoexcited thin films studied by X-ray diffraction

    PubMed Central

    Herzog, Marc; Bojahr, André; Leitenberger, Wolfram; Hertwig, Andreas; Bargheer, Matias

    2014-01-01

    Using ultrafast X-ray diffraction, we study the coherent picosecond lattice dynamics of photoexcited thin films in the two limiting cases, where the photoinduced stress profile decays on a length scale larger and smaller than the film thickness. We solve a unifying analytical model of the strain propagation for acoustic impedance-matched opaque films on a semi-infinite transparent substrate, showing that the lattice dynamics essentially depend on two parameters: One for the spatial profile and one for the amplitude of the strain. We illustrate the results by comparison with high-quality ultrafast X-ray diffraction data of SrRuO3 films on SrTiO3 substrates. PMID:26798784

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

    NASA Technical Reports Server (NTRS)

    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.

  20. Real-time Studies of Shocked Polycrystalline Materials with Single-Pulse X-ray Diffraction

    SciTech Connect

    Dane V. Morgan

    2011-05-25

    Characteristic K-α x-rays used for single-pulse XRD are conventionally produced by a 37-stage high-voltage Marx pulse generator coupled to a vacuum needle-and-washer x-ray diode via coaxial transmission line. A large field-of-view x-ray image plate detection system typically enables observation of several Debye-Scherrer rings. Recently, we have developed a fiber-optic reducer, coupled to a CCD camera, to obtain low-noise, large field-of-view images. The direct beam spot is produced by bremsstrahlung radiation attenuated by a twomillimeter tungsten beam stop. Determination of the direct beam position is necessary to perform the ring integration.

  1. X-ray diffraction studies of phase transformations in heavy-metal fluoride glasses

    NASA Technical Reports Server (NTRS)

    Bansal, N. P.; Doremus, R. H.

    1985-01-01

    Powder X-ray diffraction and differential scanning calorimetry studies of the crystallization properties of five ZrF4-based glass compositions have indicated that the crystalline phase in Zr-Ba-La-Pb fluoride glass is beta-BaZrF6; no such identification of crystal phases was obtainable, however, for the other glasses. Reversible polymorphic phase transformations occur in Zr-Ba-La-Li and Zr-Ba-La-Na fluoride glasses, upon heating to higher temperatures.

  2. Static High Pressure X-Ray Diffraction of TI-6AL-4V

    NASA Astrophysics Data System (ADS)

    Chesnut, Gary N.; Velisavljevic, Nenad; Sanchez, Lilliana

    2007-12-01

    Ti-6Al-4V was examined under static-high pressure conditions using a diamond anvil cell. The angle-dispersive x-ray diffraction experiments were performed at the Advanced Photon Source, Argonne National Laboratory. Radial and axial geometry were used to examine multiple samples. The purpose of the experiment was to generate pressure-volume data at room temperature (which is non-existent in literature) and to examine deviatoric stress effects on such a hard alloy.

  3. Crystallization and preliminary X-ray diffraction studies of antigen--antibody complexes.

    PubMed

    Chitarra-Guillon, V; Souchon, H; Boulot, G; Riottot, M M; Mariuzza, R; Tello, D; Poljak, R J

    1988-08-01

    Monoclonal antibodies of predefined specificity have been purified and crystallized as single components or complexed with their specific antigens. The intersegmental flexibility of antibody molecules has imposed the strategy of attempting to crystallize their Fab fragments separately. Intrasegmental mobility in Fabs has rarely been an obstacle to their crystallization. The immune system, however, provides a large functional and structural diversity of antibody molecules suitable for crystallization and X-ray diffraction studies. PMID:3147699

  4. A study of phase transitions in lead difluoride by use of polychromatic X-ray diffraction

    NASA Technical Reports Server (NTRS)

    Mahajan, V. K.; Chang, P. T.; Margrave, J. L.

    1975-01-01

    A polychromatic X-ray diffraction technique was used to obtain patterns of alpha-PbF2 and beta-PbF2. The results obtained at room temperature and 314 C at 1 atm, and at room temperature at 5.5 kbar, are in good agreement with published data. The advantages of the technique for high-temperature and high-pressure work are discussed.

  5. Realizing in-plane surface diffraction by x-ray multiple-beam diffraction with large incidence angle

    SciTech Connect

    Huang, Xian-Rong Gog, Thomas; Assoufid, Lahsen; Peng, Ru-Wen; Siddons, D. P.

    2014-11-03

    Based on rigorous dynamical-theory calculations, we demonstrate the principle of an x-ray multiple-beam diffraction (MBD) scheme that overcomes the long-lasting difficulties of high-resolution in-plane diffraction from crystal surfaces. This scheme only utilizes symmetric reflection geometry with large incident angles but activates the out-of-plane and in-plane diffraction processes simultaneously and separately in the continuous MBD planes. The in-plane diffraction is realized by detoured MBD, where the intermediate diffracted waves propagate parallel to the surface, which corresponds to an absolute Bragg surface diffraction configuration that is extremely sensitive to surface structures. A series of MBD diffraction and imaging techniques may be developed from this principle to study surface/interface (misfit) strains, lateral nanostructures, and phase transitions of a wide range of (pseudo)cubic crystal structures, including ultrathin epitaxial films and multilayers, quantum dots, strain-engineered semiconductor or (multi)ferroic materials, etc.

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

    PubMed

    Lambert, P K; Hustedt, C J; Vecchio, K S; Huskins, E L; Casem, D T; Gruner, S M; Tate, M W; Philipp, H T; Woll, A R; Purohit, P; Weiss, J T; Kannan, V; Ramesh, K T; Kenesei, P; Okasinski, J S; Almer, J; Zhao, M; Ananiadis, A G; Hufnagel, T C

    2014-09-01

    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(3)-10(4) s(-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. PMID:25273733

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

    NASA Astrophysics Data System (ADS)

    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.

  8. Imaging nanoscale lattice variations by machine learning of x-ray diffraction microscopy data

    DOE PAGESBeta

    Laanait, Nouamane; Zhang, Zhan; Schlepütz, Christian M.

    2016-08-09

    In this paper, we present a novel methodology based on machine learning to extract lattice variations in crystalline materials, at the nanoscale, from an x-ray Bragg diffraction-based imaging technique. By employing a full-field microscopy setup, we capture real space images of materials, with imaging contrast determined solely by the x-ray diffracted signal. The data sets that emanate from this imaging technique are a hybrid of real space information (image spatial support) and reciprocal lattice space information (image contrast), and are intrinsically multidimensional (5D). By a judicious application of established unsupervised machine learning techniques and multivariate analysis to this multidimensional datamore » cube, we show how to extract features that can be ascribed physical interpretations in terms of common structural distortions, such as lattice tilts and dislocation arrays. Finally, we demonstrate this 'big data' approach to x-ray diffraction microscopy by identifying structural defects present in an epitaxial ferroelectric thin-film of lead zirconate titanate.« less

  9. X-Ray Diffraction Analysis of NLO Crystals: Traditional Applications and More New Opportunities

    NASA Technical Reports Server (NTRS)

    Antipin, Mikhail Yu.; Clark, Ronald D.; Nesterov, Vladimir N.

    1998-01-01

    Single crystal X-ray diffraction analysis is one of the more important methods for the molecular and crystal structure determination of matter and therefore it has a great importance in material science including design and engineering of different compounds with non-linear optical (NLO) properties. It was shown in our previous publications that this method provides unique information about molecular structure of NLO compounds, their crystal symmetry and crystal packing arrays, molecular conformation and geometries and many other structural and electronic characteristics that are important for understanding the nature of NLO properties of solids. A very new application of the X-ray diffraction method is related to analysis of the electron density distribution p(r) in crystals and some of its characteristics (atomic and group charges, dipole and higher multipole moments, etc.), that may be obtained directly form the diffraction measurements. In the present work, we will discuss our preliminary low temperature high-resolution X-ray data for the m-nitroaniline (mNA) single crystal (VI). This is one of the "classical" organic NLO materials and electron density distribution analysis in this simple compound has a great scientific interest.

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

    SciTech Connect

    Lambert, P. K.; Hustedt, C. J.; Zhao, M.; Ananiadis, A. G.; Hufnagel, T. C.; Vecchio, K. S.; Huskins, E. L.; Casem, D. T.; Gruner, S. M.; Tate, M. W.; Philipp, H. T.; Purohit, P.; Weiss, J. T.; Woll, A. R.; Kannan, V.; Ramesh, K. T.; Kenesei, P.; Okasinski, J. S.; Almer, J.

    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.

  11. X-ray diffraction and equation of state of solid neon to 110 GPa

    NASA Astrophysics Data System (ADS)

    Hemley, R. J.; Zha, C. S.; Jephcoat, A. P.; Mao, H. K.; Finger, L. W.; Cox, D. E.

    1989-06-01

    Solid neon was compressed under static conditions at 300 K to pressures in the 100 GPa (megabar) range using diamond-anvil cell techniques. The crystal structure and P-V equation of state were determined by energy-dispersive x-ray diffraction with microcollimated synchrotron radiation. Pressures were determined from ruby fluorescence spectra and from x-ray diffraction of tungsten powder contained within the sample. Solid neon remains an insulator with the fcc structure to the maximum pressure of 110 GPa at 300 K, where the compression V/V0 is 0.28. The 300-K P-V isotherm measured at high pressure is in excellent agreement with the results of electronic structure calculations but is incorrectly described by pure pair potentials recently developed for neon. These results indicate that there is a significant softening of the material by many-body interactions at high pressures. Finally, the measurements of ruby fluorescence and tungsten x-ray diffraction in the neon medium obtained in this study provide an extension of the quasihydrostatic ruby pressure scale above 100 GPa.

  12. X-ray diffraction and equation of state of solid neon to 110 GPa

    SciTech Connect

    Hemley, R. J.; Zha, C. S.; Jephcoat, A. P.; Mao, H. K.; Finger, L. W.; Cox, D. E.

    1989-06-01

    Solid neon was compressed under static conditions at 300 K to pressures in the 100 GPa (megabar) range using diamond-anvil cell techniques. The crystal structure and /ital P/-/ital V/ equation of state were determined by energy-dispersive x-ray diffraction with microcollimated synchrotron radiation. Pressures were determined from ruby fluorescence spectra and from x-ray diffraction of tungsten powder contained within the sample. Solid neon remains an insulator with the fcc structure to the maximum pressure of 110 GPa at 300 K, where the compression /ital V///ital V//sub 0/ is 0.28. The 300-K /ital P/-/ital V/ isotherm measured at high pressure is in excellent agreement with the results of electronic structure calculations but is incorrectly described by pure pair potentials recently developed for neon. These results indicate that there is a significant softening of the material by many-body interactions at high pressures. Finally, the measurements of ruby fluorescence and tungsten x-ray diffraction in the neon medium obtained in this study provide an extension of the quasihydrostatic ruby pressure scale above 100 GPa.

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

    PubMed Central

    Lambert, P. K.; Hustedt, C. J.; Vecchio, K. S.; Huskins, E. L.; Casem, D. T.; Gruner, S. M.; Tate, M. W.; Philipp, H. T.; Woll, A. R.; Purohit, P.; Weiss, J. T.; Kannan, V.; Ramesh, K. T.; Kenesei, P.; Okasinski, J. S.; Almer, J.; Zhao, M.; Ananiadis, A. G.; Hufnagel, T. C.

    2014-01-01

    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 ∼103–104 s−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. PMID:25273733

  14. Femtosecond Diffractive Imaging with a Soft-X-Ray Free-Electron Laser

    SciTech Connect

    Chapman, Henry N.; Barty, Anton: AUTHOR = Bogan, Michael J.; Boutet, Sebastian; Frank, Matthias; Hau-Riege, Stefan P.; Marchesini, Stefano; Woods, Bruce W.; Bajt, Sasa; Benner, W.Henry; London, Richard A.; Plonjes, Elke; Kuhlmann, Marion; Treusch, Rolf; Dusterer, Stefan; Tschentscher, Thomas; Schneider, Jochen R.; Spiller, Eberhard; Moller, Thomas; Bostedt, Christoph; Hoener, Matthias; Shapiro, David A.; /UC, Davis /SLAC /Uppsala U. /LLNL, Livermore /Uppsala U. /Uppsala U. /SLAC /Uppsala U.

    2010-10-07

    Theory predicts that with an ultrashort and extremely bright coherent X-ray pulse, a single diffraction pattern may be recorded from a large macromolecule, a virus, or a cell before the sample explodes and turns into a plasma. Here we report the first experimental demonstration of this principle using the FLASH soft X-ray free-electron laser. An intense 25 fs, 4 x 10{sup 13} W/cm{sup 2} pulse, containing 10{sup 12} photons at 32 nm wavelength, produced a coherent diffraction pattern from a nano-structured non-periodic object, before destroying it at 60,000 K. A novel X-ray camera assured single photon detection sensitivity by filtering out parasitic scattering and plasma radiation. The reconstructed image, obtained directly from the coherent pattern by phase retrieval through oversampling, shows no measurable damage, and extends to diffraction-limited resolution. A three-dimensional data set may be assembled from such images when copies of a reproducible sample are exposed to the beam one by one.

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

    NASA Astrophysics Data System (ADS)

    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.

  16. Femtosecond diffractive imaging with a soft-X-ray free-electron laser

    NASA Astrophysics Data System (ADS)

    Chapman, Henry N.; Barty, Anton; Bogan, Michael J.; Boutet, Sébastien; Frank, Matthias; Hau-Riege, Stefan P.; Marchesini, Stefano; Woods, Bruce W.; Bajt, Saša; Benner, W. Henry; London, Richard A.; Plönjes, Elke; Kuhlmann, Marion; Treusch, Rolf; Düsterer, Stefan; Tschentscher, Thomas; Schneider, Jochen R.; Spiller, Eberhard; Möller, Thomas; Bostedt, Christoph; Hoener, Matthias; Shapiro, David A.; Hodgson, Keith O.; van der Spoel, David; Burmeister, Florian; Bergh, Magnus; Caleman, Carl; Huldt, Gösta; Seibert, M. Marvin; Maia, Filipe R. N. C.; Lee, Richard W.; Szöke, Abraham; Timneanu, Nicusor; Hajdu, Janos

    2006-12-01

    Theory predicts that, with an ultrashort and extremely bright coherent X-ray pulse, a single diffraction pattern may be recorded from a large macromolecule, a virus or a cell before the sample explodes and turns into a plasma. Here we report the first experimental demonstration of this principle using the FLASH soft-X-ray free-electron laser. An intense 25fs, 4×1013Wcm-2 pulse, containing 1012 photons at 32nm wavelength, produced a coherent diffraction pattern from a nanostructured non-periodic object, before destroying it at 60,000K. A novel X-ray camera assured single-photon detection sensitivity by filtering out parasitic scattering and plasma radiation. The reconstructed image, obtained directly from the coherent pattern by phase retrieval through oversampling, shows no measurable damage, and is reconstructed at the diffraction-limited resolution. A three-dimensional data set may be assembled from such images when copies of a reproducible sample are exposed to the beam one by one.

  17. Microstructure of Banded Polymer Spherulites: Studies with Micro-Focus X-ray Diffraction

    NASA Astrophysics Data System (ADS)

    Rosenthal, Martin; Anokhin, Denis V.; Luchnikov, Valeriy A.; Davies, Richard J.; Riekel, Christian; Burghammer, Manfred; Bar, Georg; Ivanov, Dimitri A.

    2010-11-01

    Micro-beam X-ray diffraction has been used to investigate the texture of banded spherulites of melt-crystallized poly(trimethylene terephthalate), PTT, formed in films of approximately 30 to 50 μm thickness. The WAXS micro-diffraction patterns show that at the local scale, the PTT texture is close to that of a single crystal. In agreement with previous studies using selected-area electron diffraction, it is shown that the crystal growth direction is parallel to the a-axis of the unit cell. When plotted as a function of the distance to the spherulite center, the intensity of different diffraction peaks reveals the same periodicity. This means that the lamellar twist is strictly uniform. The latter observation is more compatible with the model explaining the twist as a result of unbalanced surface stresses than that of isochiral giant screw dislocations. The main features of the experimental diffractograms can be understood using the numerical approach, which is developed in the approximation of a purely geometric broadening of X-ray reflections. In particular, the simulation can predict the sequence of appearance of different diffraction peaks and their shape on the 2D micro-diffraction patterns.

  18. X-ray structure of perdeuterated diisopropyl fluorophosphatase (DFPase): perdeuteration of proteins for neutron diffraction

    PubMed Central

    Blum, Marc-Michael; Tomanicek, Stephen J.; John, Harald; Hanson, B. Leif; Rüterjans, Heinz; Schoenborn, Benno P.; Langan, Paul; Chen, Julian C.-H.

    2010-01-01

    The signal-to-noise ratio is one of the limiting factors in neutron macromolecular crystallography. Protein perdeuteration, which replaces all H atoms with deuterium, is a method of improving the signal-to-noise ratio of neutron crystallography experiments by reducing the incoherent scattering of the hydrogen isotope. Detailed analyses of perdeuterated and hydrogenated structures are necessary in order to evaluate the utility of perdeuterated crystals for neutron diffraction studies. The room-temperature X-ray structure of perdeuterated diisopropyl fluorophosphatase (DFPase) is reported at 2.1 Å resolution. Comparison with an independently refined hydrogenated room-temperature structure of DFPase revealed no major systematic differences, although the crystals of perdeuterated DFPase did not diffract neutrons. The lack of diffraction is examined with respect to data-collection and crystallo­graphic parameters. The diffraction characteristics of successful neutron structure determinations are presented as a guideline for future neutron diffraction studies of macromolecules. X-ray diffraction to beyond 2.0 Å resolution appears to be a strong predictor of successful neutron structures. PMID:20383004

  19. X-ray diffraction studies of the contractile mechanism in single muscle fibres.

    PubMed Central

    Lombardi, Vincenzo; Piazzesi, Gabriella; Reconditi, Massimo; Linari, Marco; Lucii, Leonardo; Stewart, Alex; Sun, Yin-Biao; Boesecke, Peter; Narayanan, Theyencheri; Irving, Tom; Irving, Malcolm

    2004-01-01

    The molecular mechanism of muscle contraction was investigated in intact muscle fibres by X-ray diffraction. Changes in the intensities of the axial X-ray reflections produced by imposing rapid changes in fibre length establish the average conformation of the myosin heads during active isometric contraction, and show that the heads tilt during the elastic response to a change in fibre length and during the elementary force generating process: the working stroke. X-ray interference between the two arrays of myosin heads in each filament allows the axial motions of the heads following a sudden drop in force from the isometric level to be measured in situ with unprecedented precision. At low load, the average working stroke is 12 nm, which is consistent with crystallographic studies. The working stroke is smaller and slower at a higher load. The compliance of the actin and myosin filaments was also determined from the change in the axial spacings of the X-ray reflections following a force step, and shown to be responsible for most of the sarcomere compliance. The mechanical properties of the sarcomere depend on both the motor actions of the myosin heads and the compliance of the myosin and actin filaments. PMID:15647164

  20. Portable apparatus for in situ x-ray diffraction and fluorescence analyses of artworks.

    PubMed

    Eveno, Myriam; Moignard, Brice; Castaing, Jacques

    2011-10-01

    A portable X-ray fluorescence/X-ray diffraction (XRF/XRD) system for artwork studies has been designed constructed and tested. It is based on Debye Scherrer XRD in reflection that takes advantage of many recent improvements in the handling of X-rays (polycapillary optics; advanced two-dimensional detection). The apparatus is based on a copper anode air cooled X-ray source, and the XRD analysis is performed on a 5-20 μm thick layer from the object surface. Energy dispersive XRF elemental analysis can be performed at the same point as XRD, giving elemental compositions that support the interpretation of XRD diagrams. XRF and XRD analyses were tested to explore the quality and the limits of the analytical technique. The XRD diagrams are comparable in quality with diagrams obtained with conventional laboratory equipment. The mineral identification of materials in artwork is routinely performed with the portable XRF-XRD system. Examples are given for ceramic glazes containing crystals and for paintings where the determination of pigments is still a challenge for nondestructive analysis. For instance, lead compounds that provide a variety of color pigments can be easily identified as well as a pigment such as lapis lazuli that is difficult to identify by XRF alone. More than 70 works of art have been studied in situ in museums, monuments, etc. In addition to ceramics and paintings, these works include bronzes, manuscripts, etc., which permit improvement in the comprehension of ancient artistic techniques. PMID:21615981

  1. High-aspect-ratio line focus for an x-ray laser by a deformable mirror

    SciTech Connect

    Yoon, G.; Jitsuno, T.; Kato, Y.; Nakatsuka, M.

    1997-02-01

    A high-aspect-ratio line focus is required on a plane target in x-ray laser experiments for obtaining a high gain-length product. Inherent wave-front aberrations in line-focusing optics, which consist of a cylindrical lens and a spherical lens, are discussed with respect to beam diameter. The nonuniformity of the linewidth that is due to the aberrations is also calculated by the ABCD matrix method. A deformable mirror of a continuous plate type with a diameter of 185 mm provides an adequate wave-front distribution for compensating for the wave-front aberration. The wave-front control by the deformable mirror realizes a fine linewidth of 25 {mu}m and 18.2 mm long, corresponding to the aspect ratio of 728. The linewidth is three times the diffraction limit. The intensity distribution along the line focus is also improved. {copyright} 1997 Optical Society of America

  2. High-aspect-ratio line focus for an x-ray laser by a deformable mirror.

    PubMed

    Yoon, G Y; Jitsuno, T; Kato, Y; Nakatsuka, M

    1997-02-01

    A high-aspect-ratio line focus is required on a plane target in x-ray laser experiments for obtaining a high gain-length product. Inherent wave-front aberrations in line-focusing optics, which consist of a cylindrical lens and a spherical lens, are discussed with respect to beam diameter. The nonuniformity of the linewidth that is due to the aberrations is also calculated by the ABCD matrix method. A deformable mirror of a continuous plate type with a diameter of 185 mm provides an adequate wave-front distribution for compensating for the wave-front aberration. The wave-front control by the deformable mirror realizes a fine linewidth of 25 microm and 18.2 mm long, corresponding to the aspect ratio of 728. The linewidth is three times the diffraction limit. The intensity distribution along the line focus is also improved. PMID:18250748

  3. Multilayer graphene stacks grown by different methods-thickness measurements by X-ray diffraction, Raman spectroscopy and optical transmission

    SciTech Connect

    Tokarczyk, M. Kowalski, G.; Kępa, H.; Grodecki, K.; Drabińska, A.; Strupiński, W.

    2013-12-15

    X-ray diffraction, Raman spectroscopy and Optical absorption estimates of the thickness of graphene multi layer stacks (number of graphene layers) are presented for three different growth techniques. The objective of this work was focused on comparison and reconciliation of the two already widely used methods for thickness estimates (Raman and Absorption) with the calibration of the X-ray method as far as Scherer constant K is concerned and X-ray based Wagner-Aqua extrapolation method.

  4. Formation of x-ray vortex dipoles using a single diffraction pattern and direct phase measurement using interferometry

    SciTech Connect

    Kohmura, Yoshiki; Sawada, Kei; Taguchi, Munetaka; Ishikawa, Tetsuya; Ohigashi, Takuji; Suzuki, Yoshio

    2009-03-09

    We have devised a method for generating x-ray vortices by using a diffraction pattern from a simple aperture with illumination wave fronts with spherical curvatures. The interferometry visualized the x-ray vortex dipoles by the direct phase measurement. Our interference technique enabled us to sensitively detect and quantitatively measure various phase dislocations on the x-ray wave fronts, providing useful methodologies for beam diagnostics and materials science.

  5. Grazing-incidence X-ray diffraction from a crystal with subsurface defects

    SciTech Connect

    Gaevskii, A. Yu. Golentus, I. E.

    2015-03-15

    The diffraction of X rays incident on a crystal surface under grazing angles under conditions of total external reflection has been investigated. An approach is proposed in which exact solutions to the dynamic problem of grazing-incidence diffraction in an ideal crystal are used as initial functions to calculate the diffuse component of diffraction in a crystal with defects. The diffuse component of diffraction is calculated for a crystal with surface defects of a dilatation-center type. Exact formulas of the continuum theory which take into account the mirror-image forces are used for defect-induced atomic displacements. Scattering intensity maps near Bragg peaks are constructed for different scan modes, and the conditions for detecting primarily the diffuse component are determined. The results of dynamic calculations of grazing-incidence diffraction in defect-containing crystals are compared with calculations in the kinematic approximation.

  6. X-ray and neutron diffraction measurements of dislocation density and subgrain size in a friction stir welded aluminum alloy

    SciTech Connect

    Claussen, Bjorn; Woo, Wanchuck; Zhili, Feng; Edward, Kenik; Ungar, Tamas

    2009-01-01

    The dislocation density and subgrain size were determined in the base material and friction-stir welds of 6061-T6 aluminum alloy. High-resolution X-ray diffraction measurement was performed in the base material. The result of the line profile analysis of the X-ray diffraction peak shows that the dislocation density is about 4.5 x 10{sup 14} m{sup 02} and the subgrain size is about 200 nm. Meanwhile, neutron diffraction measurements have been performed to observe the diffraction peaks during friction-stir welding (FSW). The deep penetration capability of the neutron enables us to measure the peaks from the midplane of the Al plate underneath the tool shoulder of the friction-stir welds. The peak broadening analysis result using the Williamson-Hall method shows the dislocation density of about 3.2 x 10{sup 15} m{sup -2} and subgrain size of about 160 nm. The significant increase of the dislocation density is likely due to the severe plastic deformation during FSW. This study provides an insight into understanding the transient behavior of the microstructure under severe thermomechanical deformation.

  7. PREFACE: XTOP 2004 -- 7th Biennial Conference on High Resolution X-Ray Diffraction and Imaging

    NASA Astrophysics Data System (ADS)

    Holý, Vaclav

    2005-05-01

    The 7th Biennial Conference on High Resolution X-Ray Diffraction and Imaging (XTOP 2004) was held in the Prague suburb of Pruhonice, Czech Republic, during 7-10 September 2004. It was organized by the Czech and Slovak Crystallographic Association in cooperation with the Institute of Physics, Academy of Sciences of the Czech Republic, Prague, Masaryk University, Brno, and Charles University, Prague. XTOP 2004 took place just after EPDIC IX (European Powder Diffraction Conference) organised in Prague by the same Association during 2-5 September 2004. The Organizing Committee was supported by an International Programme Committee including about 20 prominent scientists from several European and overseas countries, whose helpful suggestions for speakers are acknowledged. The conference was sponsored by the International Union of Crystallography and by several industrial sponsors; this sponsorship allowed us to support about 20 students and young scientists. In total, 147 official delegates and 8 accompanying persons from 16 countries of three continents attended our conference. The scientific programme of the conference was divided into 11 half-day sessions and 2 poster sessions. The participants presented 147 accepted contributions; of these 9 were 45-minute long invited talks, 34 were 20-minute oral presentations and 104 were posters. All posters were displayed for the whole meeting to ensure maximum exposure and interaction between delegates. We followed the very good experience from the previous conference, XTOP 2002, and also organized pre-conference tutorial lectures presented by experts in the field: `Imaging with hard synchrotron radiation' (J Härtwig, Grenoble), `High-resolution x-ray diffractometry: determination of strain and composition' (J Stangl, Linz), `X-ray grazing-incidence scattering from surfaces and nanostructures' (U Pietsch, Potsdam) and `Hard x-ray optics' (J Hrdý, Prague). According to the recommendation of the International Program Committee

  8. Diffractive imaging at large Fresnel number: Challenge of dynamic mesoscale imaging with hard x rays

    NASA Astrophysics Data System (ADS)

    Barber, John L.; Barnes, Cris W.; Sandberg, Richard L.; Sheffield, Richard L.

    2014-05-01

    Real materials have structure at both the atomic or crystalline scale as well as at interfaces and defects at the larger scale of grains. There is a need for the study of materials at the "mesoscale," the scale at which subgranular physical processes and intergranular organization couple to determine microstructure, crucially impacting constitutive response at the engineering macroscale. Diffractive imaging using photons that can penetrate multiple grains of material would be a transformative technique for the study of the performance of materials in dynamic extremes. Thicker samples imply higher energy photons of shorter wavelength, and imaging of multiple grains implies bigger spot sizes. Such imaging requires the use of future planned and proposed hard x-ray free electron lasers (such as the European XFEL) to provide both the spatial coherence transverse to the large spots and the peak brilliance to provide the short illumination times. The result is that the Fresnel number of the system becomes large and is no longer in the Fraunhofer far-field limit. The interrelated issues of diffractive imaging at large Fresnel number are analyzed, including proof that diffractive imaging is possible in this limit and estimates of the signal-to-noise possible. In addition, derivation of the heating rates for brilliant pulses of x rays are presented. The potential and limitations on multiple dynamic images are derived. This paper will present a study of x-ray interactions with materials in this new regime of spatially coherent but relatively large mesoscale spots at very hard energies. It should provide the theory and design background for the experiments and facilities required to control materials in extreme environments, in particular for the next generation of very-hard-x-ray free electron lasers.

  9. Time-Domain X-ray Diffraction in the Pulsed Laser Heated Diamond Anvil Cell

    NASA Astrophysics Data System (ADS)

    Prakapenka, V.; Goncharov, A. F.; Struzhkin, V.; Kantor, I.; Rivers, M. L.; Dalton, D. A.

    2011-12-01

    We have developed in situ x-ray synchrotron diffraction measurements of samples heated by a pulsed laser in the diamond anvil cell (DAC) at pressure up to 100 GPa and 3500 K. We used an electronically modulated 2-10 kHz repetition rate, 1064-1075 nm fiber laser with 1-100 microseconds pulse width synchronized with a gated x-ray detector (Pilatus) and time resolved radiometric temperature measurements. For the special APS hybrid mode, the measurements were also synchronized with a 500 ns long bunch carrying 88% of the ring current. This setup enables time domain measurements as a function of temperature in a micrometers time scale (averaged over many events, typically more than 10,000). X-ray diffraction data, temperature measurements, and finite element calculations with realistic geometric and thermochemical parameters show that in the present experimental configuration samples 4 micrometers thick can be continuously temperature monitored (up to 3000 K in our experiments) with the same level of axial and radial temperature uniformity as with continuous heating. We find that this novel technique offers a new and convenient way of fine tuning the maximum sample temperature by changing the pulse width of the laser. We will show examples of studies of the melting, thermal equation of state, and chemical reactivity. We acknowledge support from NSF EAR-0842057, DOE/ NNSA (CDAC), and EFree, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences under Award No. DESC0001057. X-ray diffraction measurements were performed at GSECARS (APS) supported by DOE Contract No.W-31-109- Eng-38.

  10. Time-resolved coherent X-ray diffraction imaging of surface acoustic waves

    PubMed Central

    Nicolas, Jan-David; Reusch, Tobias; Osterhoff, Markus; Sprung, Michael; Schülein, Florian J. R.; Krenner, Hubert J.; Wixforth, Achim; Salditt, Tim

    2014-01-01

    Time-resolved coherent X-ray diffraction experiments of standing surface acoustic waves, illuminated under grazing incidence by a nanofocused synchrotron beam, are reported. The data have been recorded in stroboscopic mode at controlled and varied phase between the acoustic frequency generator and the synchrotron bunch train. At each time delay (phase angle), the coherent far-field diffraction pattern in the small-angle regime is inverted by an iterative algorithm to yield the local instantaneous surface height profile along the optical axis. The results show that periodic nanoscale dynamics can be imaged at high temporal resolution in the range of 50 ps (pulse length). PMID:25294979

  11. High resolution X-ray diffraction imaging of lead tin telluride

    NASA Technical Reports Server (NTRS)

    Steiner, Bruce; Dobbyn, Ronald C.; Black, David; Burdette, Harold; Kuriyama, Masao; Spal, Richard; Simchick, Richard; Fripp, Archibald

    1991-01-01

    High resolution X-ray diffraction images of two directly comparable crystals of lead tin telluride, one Bridgman-grown on Space Shuttle STS 61A and the other terrestrially Bridgman-grown under similar conditions from identical material, present different subgrain structure. In the terrestrial, sample 1 the appearance of an elaborate array of subgrains is closely associated with the intrusion of regions that are out of diffraction in all of the various images. The formation of this elaborate subgrain structure is inhibited by growth in microgravity.

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

    SciTech Connect

    Nascimento, Alessandro S.; Ferrarezi, Thiago; Catalano-Dupuy, Daniela L.; Ceccarelli, Eduardo A.; Polikarpov, Igor

    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.

  13. Streaked speckle in Cu{sub 3}Au coherent x-ray diffraction

    SciTech Connect

    Pitney, J. A.; Robinson, I. K.; Vartaniants, I. A.; Appleton, R.; Flynn, C. P.

    2000-11-15

    Coherent x-ray diffraction from the binary alloy Cu{sub 3}Au has speckled superstructure Bragg reflections due to its antiphase domain structure. For nonspecular superstructure reflections, it is possible to vary the diffraction geometry through a range of incidence and exit angles. Under grazing-exit conditions on a prepared Cu{sub 3}Au(111) thin-film sample, the superstructure speckles are found to become highly elongated and rotated on the detector. A detailed geometrical explanation of this behavior is developed to explain the effect.

  14. X-ray third-order nonlinear dynamical diffraction in a crystal

    SciTech Connect

    Balyan, M. K.

    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.

  15. On the microstructure of nanoporous gold: an x-ray diffraction study

    SciTech Connect

    Van Petegem, S; Brandstetter, S; Maa?, R; Schmitt, B; Borca, C; Van Swygenhoven, H; Hodge, A M; El-Dasher, B S; Biener, J

    2008-08-26

    The evolution of the grain structure, internal stresses, and the lattice misorientations of nanoporous gold (npAu) 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. Furthermore, most grains develop in-plane tensile stress. The feature size of the developing nanoporous structure increases with increasing dealloying time.

  16. Simulating picosecond X-ray diffraction from crystals using FFT methods on MD output

    SciTech Connect

    Kimminau, Giles; Nagler, Bob; Higginbotham, Andrew; Murphy, William; Wark, Justin; Park, Nigel; Hawreliak, James; Kalantar, Dan; Lorenzana, Hector; Remington, Bruce

    2007-12-12

    Multi-million atom non-equilibrium molecular dynamics (MD) simulations give significant insight into the transient processes that occur under shock compression. Picosecond X-ray diffraction enables the probing of materials on a timescale fast enough to test such effects. In order to simulate diffraction patterns, Fourier methods are required to gain a picture of reciprocal lattice space. We present here results of fast Fourier transforms of atomic coordinates of shocked crystals simulated by MD, and comment on the computing power required as a function of problem size. The relationship between reciprocal space and particular experimental geometries is discussed.

  17. Combination of Raman, Infrared, and X-Ray Energy-Dispersion Spectroscopies and X-Ray Diffraction to Study a Fossilization Process

    NASA Astrophysics Data System (ADS)

    de Sousa Filho, Francisco Eduardo; da Silva, João Hermínio; Feitosa Saraiva, Antônio Álamo; Brito, Deyvid Dennys S.; Viana, Bartolomeu Cruz; de Oliveira Abagaro, Bruno Tavares; de Tarso Cavalcante Freire, Paulo

    2011-12-01

    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.

  18. Energy dispersive X-ray diffraction in the diamond anvil, high-pressure apparatus - Comparison of synchrotron and conventional X-ray sources

    NASA Technical Reports Server (NTRS)

    Spain, I. L.; Black, D. R.

    1985-01-01

    The use of both conventional fixed-anode X-ray sources and synchrotron radiation to carry out energy-dispersive X-ray diffraction experiments at high pressure in a diamond anvil cell, is discussed. The photon flux at the sample and at the detector for the two cases are compared and the results are presented in graphs. It is shown that synchrotron radiation experiments can be performed with nearly two orders of magnitude increase in data rate if superior detectors and detector electronics are available.

  19. Real-time, high-resolution x-ray diffraction measurements on shocked crystals at a synchrotron facility

    NASA Astrophysics Data System (ADS)

    Gupta, Y. M.; Turneaure, Stefan J.; Perkins, K.; Zimmerman, K.; Arganbright, N.; Shen, G.; Chow, P.

    2012-12-01

    The Advanced Photon Source (APS) at Argonne National Laboratory was used to obtain real-time, high-resolution x-ray diffraction measurements to determine the microscopic response of shock-compressed single crystals. Disk shaped samples were subjected to plane shock wave compression by impacting them with half-inch diameter, flat-faced projectiles. The projectiles were accelerated to velocities ranging between 300 and 1200 m/s using a compact powder gun designed specifically for use at a synchrotron facility. The experiments were designed to keep the sample probed volume under uniaxial strain and constant stress for a duration longer than the 153.4 ns spacing between x-ray bunches. X-rays from a single pulse (<100 ps duration) out of the periodic x-ray pulses emitted by the synchrotron were used for the diffraction measurements. A synchronization and x-ray detection technique was developed to ensure that the measured signal was obtained unambiguously from the desired x-ray pulse incident on the sample while the sample was in a constant uniaxial strain state. The synchronization and x-ray detection techniques described can be used for a variety of x-ray measurements on shock compressed solids and liquids at the APS. Detailed procedures for applying the Bragg-Brentano parafocusing approach to single crystals at the APS are presented. Analytic developments to determine the effects of crystal substructure and non-ideal geometry on the diffraction pattern position and shape are presented. Representative real-time x-ray diffraction data, indicating shock-induced microstructural changes, are presented for a shock-compressed Al(111) sample. The experimental developments presented here provided, in part, the impetus for the Dynamic Compression Sector (DCS) currently under development at the APS. Both the synchronization/x-ray detection methods and the analysis equations for high-resolution single crystal x-ray diffraction can be used at the DCS.

  20. Peculiarities of section topograms for the multiple diffraction of X rays

    NASA Astrophysics Data System (ADS)

    Kohn, V. G.; Smirnova, I. A.

    2016-07-01

    The distortion of interference fringes on the section topograms of single crystal due to the multiple diffraction of X rays has been investigated. The cases of the 220 and 400 reflections in a silicon crystal in the form of a plate with a surface oriented normally to the [001] direction are considered both theoretically and experimentally. The same section topogram exhibits five cases of multiple diffraction at small azimuthal angles for the 400 reflection and Mo K α radiation, while the topogram for the 220 reflection demonstrates two cases of multiple diffraction. All these cases correspond to different combinations of reciprocal lattice vectors. Exact theoretical calculations of section topograms for the aforementioned cases of multiple diffraction have been performed for the first time. The section topograms exhibit two different distortion regions. The distortions in the central region of the structure are fairly complex and depend strongly on the azimuthal angle. In the tails of the multiple diffraction region, there is a shift of two-beam interference fringes, which can be observed even with a laboratory X-ray source.

  1. Tomography of a Cryo-immobilized Yeast Cell Using Ptychographic Coherent X-Ray Diffractive Imaging.

    PubMed

    Giewekemeyer, K; Hackenberg, C; Aquila, A; Wilke, R N; Groves, M R; Jordanova, R; Lamzin, V S; Borchers, G; Saksl, K; Zozulya, A V; Sprung, M; Mancuso, A P

    2015-11-01

    The structural investigation of noncrystalline, soft biological matter using x-rays is of rapidly increasing interest. Large-scale x-ray sources, such as synchrotrons and x-ray free electron lasers, are becoming ever brighter and make the study of such weakly scattering materials more feasible. Variants of coherent diffractive imaging (CDI) are particularly attractive, as the absence of an objective lens between sample and detector ensures that no x-ray photons scattered by a sample are lost in a limited-efficiency imaging system. Furthermore, the reconstructed complex image contains quantitative density information, most directly accessible through its phase, which is proportional to the projected electron density of the sample. If applied in three dimensions, CDI can thus recover the sample's electron density distribution. As the extension to three dimensions is accompanied by a considerable dose applied to the sample, cryogenic cooling is necessary to optimize the structural preservation of a unique sample in the beam. This, however, imposes considerable technical challenges on the experimental realization. Here, we show a route toward the solution of these challenges using ptychographic CDI (PCDI), a scanning variant of coherent imaging. We present an experimental demonstration of the combination of three-dimensional structure determination through PCDI with a cryogenically cooled biological sample--a budding yeast cell (Saccharomyces cerevisiae)--using hard (7.9 keV) synchrotron x-rays. This proof-of-principle demonstration in particular illustrates the potential of PCDI for highly sensitive, quantitative three-dimensional density determination of cryogenically cooled, hydrated, and unstained biological matter and paves the way to future studies of unique, nonreproducible biological cells at higher resolution. PMID:26536275

  2. Nondestructive evaluation of residual stress in short-fiber reinforced plastics by x-ray diffraction

    NASA Astrophysics Data System (ADS)

    Tanaka, Keisuke; Tokoro, Syouhei; Akiniwa, Yoshiaki; Egami, Noboru

    2014-06-01

    The X-ray diffraction method is used to measure the residual stress in injection-molded plates of short-fiber reinforced plastics (SFRP) made of crystalline thermoplastics, polyphenylene sulphide (PPS), reinforced by carbon fibers with 30 mass%. Based on the orientation of carbon fibers, injection molded plates can be modeled as three-layered lamella where the core layer is sandwiched by skin layers. The stress in the matrix in the skin layer was measured using Cr-Kα radiation with the sin2Ψ method. Since the X-ray penetration depth is shallow, the state of stresses measured by X-rays in FRP can be assumed to be plane stress. The X-ray measurement of stress in carbon fibers was not possible because of high texture. A new method was proposed to evaluate the macrostress in SFRP from the measurement of the matrix stress. According to micromechanics analysis of SFRP, the matrix stresses in the fiber direction, σ1m, and perpendicular to the fiber direction, σ2m, and shear stress τ12m can be expressed as the functions of the applied (macro-) stresses, σ1A, σ2A , τ12A as follows: σ1m = α11σ1A +α12σ2A, σ2m = α21σ1A + α22σ2A, τ12m = α66τ12A, where α11 ,α12, α21, α22, α66 are stress-partitioning coefficients. Using skin-layer strips cut parallel, perpendicular and 45° to the molding direction, the stress in the matrix was measured under the uniaxial applied stress and the stress-partitioning coefficients of the above equations were determined. Once these relations are established, the macrostress in SFRP can be determined from the measurements of the matrix stresses by X-rays.

  3. Room temperature femtosecond X-ray diffraction of photosystem II microcrystals

    PubMed Central

    Kern, Jan; Alonso-Mori, Roberto; Hellmich, Julia; Tran, Rosalie; Hattne, Johan; Laksmono, Hartawan; Glöckner, Carina; Echols, Nathaniel; Sierra, Raymond G.; Sellberg, Jonas; Lassalle-Kaiser, Benedikt; Gildea, Richard J.; Glatzel, Pieter; Grosse-Kunstleve, Ralf W.; Latimer, Matthew J.; McQueen, Trevor A.; DiFiore, Dörte; Fry, Alan R.; Messerschmidt, Marc; Miahnahri, Alan; Schafer, Donald W.; Seibert, M. Marvin; Sokaras, Dimosthenis; Weng, Tsu-Chien; Zwart, Petrus H.; White, William E.; Adams, Paul D.; Bogan, Michael J.; Boutet, Sébastien; Williams, Garth J.; Messinger, Johannes; Sauter, Nicholas K.; Zouni, Athina; Bergmann, Uwe; Yano, Junko; Yachandra, Vittal K.

    2012-01-01

    Most of the dioxygen on earth is generated by the oxidation of water by photosystem II (PS II) using light from the sun. This light-driven, four-photon reaction is catalyzed by the Mn4CaO5 cluster located at the lumenal side of PS II. Various X-ray studies have been carried out at cryogenic temperatures to understand the intermediate steps involved in the water oxidation mechanism. However, the necessity for collecting data at room temperature, especially for studying the transient steps during the O–O bond formation, requires the development of new methodologies. In this paper we report room temperature X-ray diffraction data of PS II microcrystals obtained using ultrashort (< 50 fs) 9 keV X-ray pulses from a hard X-ray free electron laser, namely the Linac Coherent Light Source. The results presented here demonstrate that the ”probe before destroy” approach using an X-ray free electron laser works even for the highly-sensitive Mn4CaO5 cluster in PS II at room temperature. We show that these data are comparable to those obtained in synchrotron radiation studies as seen by the similarities in the overall structure of the helices, the protein subunits and the location of the various cofactors. This work is, therefore, an important step toward future studies for resolving the structure of the Mn4CaO5 cluster without any damage at room temperature, and of the reaction intermediates of PS II during O–O bond formation. PMID:22665786

  4. Hybrid quantitative simulation on the in-line phase-contrast x-ray imaging of three dimensional samples under actual clinic imaging parameters

    SciTech Connect

    Yu Hong; Han Shensheng; Ding Jianhui; Jiang Zhaoxia; Peng Weijun

    2009-07-06

    A hybrid model combining Monte Carlo method with diffraction theory of wave optics has been developed and applied to quantitatively simulate the in-line diffractive phase-contrast x-ray imaging of three dimensional tissue samples under actual clinic imaging parameters. The primary microcosmic interactions of medical-energy x-ray within matter including photoabsorption, Compton scattering, and coherent scattering, have been taken into account in the Monte Carlo simulation. A diffraction processing based on Fresnel diffraction theory is carried out to simulate the macroscopic diffraction effect. A comparison with experiment results has also been performed.

  5. Imaging live cell in micro-liquid enclosure by X-ray laser diffraction

    PubMed Central

    Kimura, Takashi; Joti, Yasumasa; Shibuya, Akemi; Song, Changyong; Kim, Sangsoo; Tono, Kensuke; Yabashi, Makina; Tamakoshi, Masatada; Moriya, Toshiyuki; Oshima, Tairo; Ishikawa, Tetsuya; Bessho, Yoshitaka; Nishino, Yoshinori

    2014-01-01

    Emerging X-ray free-electron lasers with femtosecond pulse duration enable single-shot snapshot imaging almost free from sample damage by outrunning major radiation damage processes. In bioimaging, it is essential to keep the sample close to its natural state. Conventional high-resolution imaging, however, suffers from severe radiation damage that hinders live cell imaging. Here we present a method for capturing snapshots of live cells kept in a micro-liquid enclosure array by X-ray laser diffraction. We place living Microbacterium lacticum cells in an enclosure array and successively expose each enclosure to a single X-ray laser pulse from the SPring-8 Angstrom Compact Free-Electron Laser. The enclosure itself works as a guard slit and allows us to record a coherent diffraction pattern from a weakly-scattering submicrometre-sized cell with a clear fringe extending up to a 28-nm full-period resolution. The reconstructed image reveals living whole-cell structures without any staining, which helps advance understanding of intracellular phenomena. PMID:24394916

  6. X-ray diffraction imaging--a multi-generational perspective.

    PubMed

    Harding, G

    2009-02-01

    A brief description is given of some applications of X-ray diffraction imaging (XDI) in security screening, including detection of narcotics and a wide range of explosives: organic (plastic) explosives, liquids, home-made explosives (HMEs) and special nuclear materials (SNMs). A Bayesian formulation of the "rare event scenario" is presented, allowing the probability to be quantified that an unlikely threat is indeed present when an uncertain detection system raises an alarm. Granted the utility of X-ray diffraction (XRD) as a significant screening modality for false-alarm resolution, the topic of its technological feasibility is addressed. It is shown that, in analogy to computed tomography, XDI permits a significant reduction to be achieved in measurement time per object volume element (voxel) compared with that of a classical X-ray diffractometer. This reduction can be accomplished by designing the XDI system to record energy-dispersive XRD profiles from many volume elements (object voxels) in parallel. A general scheme for designing "massively-parallel" (MP) XDI systems is presented. XDI configurations of the first generation (1 voxels(-1)), second generation (100 voxelss(-1)) and third generation (10(4) voxelss(-1)) are presented and discussed. Three alternative 3rd Generation XDI geometries, namely: direct fan-beam; parallel (waterfall) beam; and inverse fan-beam are compared with respect to technological realization. Directions for future development of XDI in screening applications are outlined. PMID:18805014

  7. X-ray diffraction in the pulsed laser heated diamond anvil cell

    SciTech Connect

    Goncharov, Alexander F.; Prakapenka, Vitali B.; Struzhkin, Viktor V.; Kantor, Innokenty; Rivers, Mark L.; Dalton, D. Allen

    2010-11-03

    We have developed in situ x-ray synchrotron diffraction measurements of samples heated by a pulsed laser in the diamond anvil cell at pressure up to 60 GPa. We used an electronically modulated 2–10 kHz repetition rate, 1064–1075 nm fiber laser with 1–100 μs pulse width synchronized with a gated x-ray detector (Pilatus) and time-resolved radiometric temperature measurements. This enables the time domain measurements as a function of temperature in a microsecond time scale (averaged over many events, typically more than 10,000). X-ray diffraction data, temperature measurements, and finite element calculations with realistic geometric and thermochemical parameters show that in the present experimental configuration, samples 4 μm thick can be continuously temperature monitored (up to 3000 K in our experiments) with the same level of axial and radial temperature uniformities as with continuous heating. We find that this novel technique offers a new and convenient way of fine tuning the maximum sample temperature by changing the pulse width of the laser. This delicate control, which may also prevent chemical reactivity and diffusion, enables accurate measurement of melting curves, phase changes, and thermal equations of state.

  8. X-ray diffraction in the pulsed laser heated diamond anvil cell

    SciTech Connect

    Goncharov, Alexander F.; Prakapenka, Vitali B.; Struzhkin, Viktor V.; Kantor, Innokenty; Rivers, Mark L.; Dalton, D. Allen

    2010-11-19

    We have developed in situ x-ray synchrotron diffraction measurements of samples heated by a pulsed laser in the diamond anvil cell at pressure up to 60 GPa. We used an electronically modulated 2-10 kHz repetition rate, 1064-1075 nm fiber laser with 1-100 {micro}s pulse width synchronized with a gated x-ray detector (Pilatus) and time-resolved radiometric temperature measurements. This enables the time domain measurements as a function of temperature in a microsecond time scale (averaged over many events, typically more than 10,000). X-ray diffraction data, temperature measurements, and finite element calculations with realistic geometric and thermochemical parameters show that in the present experimental configuration, samples 4 {micro}m thick can be continuously temperature monitored (up to 3000 K in our experiments) with the same level of axial and radial temperature uniformities as with continuous heating. We find that this novel technique offers a new and convenient way of fine tuning the maximum sample temperature by changing the pulse width of the laser. This delicate control, which may also prevent chemical reactivity and diffusion, enables accurate measurement of melting curves, phase changes, and thermal equations of state.

  9. X-ray diffraction in the pulsed laser heated diamond anvil cell

    SciTech Connect

    Goncharov, Alexander F.; Struzhkin, Viktor V.; Dalton, D. Allen; Prakapenka, Vitali B.; Kantor, Innokenty; Rivers, Mark L.

    2010-11-15

    We have developed in situ x-ray synchrotron diffraction measurements of samples heated by a pulsed laser in the diamond anvil cell at pressure up to 60 GPa. We used an electronically modulated 2-10 kHz repetition rate, 1064-1075 nm fiber laser with 1-100 {mu}s pulse width synchronized with a gated x-ray detector (Pilatus) and time-resolved radiometric temperature measurements. This enables the time domain measurements as a function of temperature in a microsecond time scale (averaged over many events, typically more than 10 000). X-ray diffraction data, temperature measurements, and finite element calculations with realistic geometric and thermochemical parameters show that in the present experimental configuration, samples 4 {mu}m thick can be continuously temperature monitored (up to 3000 K in our experiments) with the same level of axial and radial temperature uniformities as with continuous heating. We find that this novel technique offers a new and convenient way of fine tuning the maximum sample temperature by changing the pulse width of the laser. This delicate control, which may also prevent chemical reactivity and diffusion, enables accurate measurement of melting curves, phase changes, and thermal equations of state.

  10. Reconstruction of an astigmatic hard X-ray beam and alignment of K-B mirrors from ptychographic coherent diffraction data.

    PubMed

    Kewish, Cameron M; Guizar-Sicairos, Manuel; Liu, Chian; Qian, Jun; Shi, Bing; Benson, Christa; Khounsary, Ali M; Vila-Comamala, Joan; Bunk, Oliver; Fienup, James R; Macrander, Albert T; Assoufid, Lahsen

    2010-10-25

    We have used coherent X-ray diffraction experiments to characterize both the 1-D and 2-D foci produced by nanofocusing Kirkpatrick-Baez (K-B) mirrors, and we find agreement. Algorithms related to ptychography were used to obtain a 3-D reconstruction of a focused hard X-ray beam waist, using data measured when the mirrors were not optimally aligned. Considerable astigmatism was evident in the reconstructed complex wavefield. Comparing the reconstructed wavefield for a single mirror with a geometrical projection of the wavefront errors expected from optical metrology data allowed us to diagnose a 40 μrad misalignment in the incident angle of the first mirror, which had occurred during the experiment. Good agreement between the reconstructed wavefront obtained from the X-ray data and off-line metrology data obtained with visible light demonstrates the usefulness of the technique as a metrology and alignment tool for nanofocusing X-ray optics. PMID:21164684

  11. Characterization of ion beam sputtered deposited W/Si multilayers by grazing incidence x-ray diffraction and x-ray reflectivity technique

    NASA Astrophysics Data System (ADS)

    Dhawan, Rajnish; Rai, Sanjay

    2016-05-01

    W/Si multilayers four samples have been deposited on silicon substrate using ion beam sputtering system. Thickness of tungsten (W) varies from around 10 Å to 40 Å while the silicon (Si) thickness remains constant at around 30 Å in multilayers [W-Si]x4. The samples have been characterized by grazing incidence X-ray diffraction (GIXRD) and X-ray reflectivity technique (XRR). GIXRD study shows the crystalline behaviour of W/Si multilayer by varying W thickness and it is found that above 20 Å the W film transform from amorphous to crystalline phase and X-ray reflectivity data shows that the roughnesses of W increases on increasing the W thicknesses in W/Si multilayers.

  12. DynAMITe: a prototype large area CMOS APS for breast cancer diagnosis using x-ray diffraction measurements

    NASA Astrophysics Data System (ADS)

    Konstantinidis, A.; Anaxagoras, T.; Esposito, M.; Allinson, N.; Speller, R.

    2012-03-01

    X-ray diffraction studies are used to identify specific materials. Several laboratory-based x-ray diffraction studies were made for breast cancer diagnosis. Ideally a large area, low noise, linear and wide dynamic range digital x-ray detector is required to perform x-ray diffraction measurements. Recently, digital detectors based on Complementary Metal-Oxide- Semiconductor (CMOS) Active Pixel Sensor (APS) technology have been used in x-ray diffraction studies. Two APS detectors, namely Vanilla and Large Area Sensor (LAS), were developed by the Multidimensional Integrated Intelligent Imaging (MI-3) consortium to cover a range of scientific applications including x-ray diffraction. The MI-3 Plus consortium developed a novel large area APS, named as Dynamically Adjustable Medical Imaging Technology (DynAMITe), to combine the key characteristics of Vanilla and LAS with a number of extra features. The active area (12.8 × 13.1 cm2) of DynaMITe offers the ability of angle dispersive x-ray diffraction (ADXRD). The current study demonstrates the feasibility of using DynaMITe for breast cancer diagnosis by identifying six breast-equivalent plastics. Further work will be done to optimize the system in order to perform ADXRD for identification of suspicious areas of breast tissue following a conventional mammogram taken with the same sensor.

  13. Microelemental and mineral compositions of pathogenic biomineral concrements: SRXFA, X-ray powder diffraction and vibrational spectroscopy data

    NASA Astrophysics Data System (ADS)

    Moroz, T. N.; Palchik, N. A.; Dar'in, A. V.

    2009-05-01

    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.

  14. X-ray Diffraction Results from Mars Science Laboratory: Mineralogy of Rocknest at Gale Crater

    NASA Astrophysics Data System (ADS)

    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.; Achilles, Cherie; Agard, Christophe; Verdasca, José Alexandre Alves; Anderson, Robert; Anderson, Ryan; Archer, Doug; Armiens-Aparicio, Carlos; Arvidson, Ray; Atlaskin, Evgeny; Atreya, Sushil; Aubrey, Andrew; Baker, Burt; Baker, Michael; Balic-Zunic, Tonci; Baratoux, David; Baroukh, Julien; Barraclough, Bruce; Bean, Keri; Beegle, Luther; Behar, Alberto; Bell, James; Bender, Steve; Benna, Mehdi; Bentz, Jennifer; Berger, Gilles; Berger, Jeff; Berman, Daniel; Bish, David; Blake, David F.; Avalos, Juan J. Blanco; Blaney, Diana; Blank, Jen; Blau, Hannah; Bleacher, Lora; Boehm, Eckart; Botta, Oliver; Böttcher, Stephan; Boucher, Thomas; Bower, Hannah; Boyd, Nick; Boynton, Bill; Breves, Elly; Bridges, John; Bridges, Nathan; Brinckerhoff, William; Brinza, David; Bristow, Thomas; Brunet, Claude; Brunner, Anna; Brunner, Will; Buch, Arnaud; Bullock, Mark; Burmeister, Sönke; Cabane, Michel; Calef, Fred; Cameron, James; Campbell, John "Iain"; Cantor, Bruce; Caplinger, Michael; Rodríguez, Javier Caride; Carmosino, Marco; Blázquez, Isaías Carrasco; Charpentier, Antoine; Chipera, Steve; Choi, David; Clark, Benton; Clegg, Sam; Cleghorn, Timothy; Cloutis, Ed; Cody, George; Coll, Patrice; Conrad, Pamela; Coscia, David; Cousin, Agnès; Cremers, David; Crisp, Joy; Cros, Alain; Cucinotta, Frank; d'Uston, Claude; Davis, Scott; Day, Mackenzie "Kenzie"; Juarez, Manuel de la Torre; DeFlores, Lauren; DeLapp, Dorothea; DeMarines, Julia; DesMarais, David; Dietrich, William; Dingler, Robert; Donny, Christophe; Downs, Bob; Drake, Darrell; Dromart, Gilles; Dupont, Audrey; Duston, Brian; Dworkin, Jason; Dyar, M. Darby; Edgar, Lauren; Edgett, Kenneth; Edwards, Christopher; Edwards, Laurence; Ehlmann, Bethany; Ehresmann, Bent; Eigenbrode, Jen; Elliott, Beverley; Elliott, Harvey; Ewing, Ryan; Fabre, Cécile; Fairén, Alberto; Farley, Ken; Farmer, Jack; Fassett, Caleb; Favot, Laurent; Fay, Donald; Fedosov, Fedor; Feldman, Jason; Feldman, Sabrina; Fisk, Marty; Fitzgibbon, Mike; Flesch, Greg; Floyd, Melissa; Flückiger, Lorenzo; Forni, Olivier; Fraeman, Abby; Francis, Raymond; François, Pascaline; Franz, Heather; Freissinet, Caroline; French, Katherine Louise; Frydenvang, Jens; Gaboriaud, Alain; Gailhanou, Marc; Garvin, James; Gasnault, Olivier; Geffroy, Claude; Gellert, Ralf; Genzer, Maria; Glavin, Daniel; Godber, Austin; Goesmann, Fred; Goetz, Walter; Golovin, Dmitry; Gómez, Felipe Gómez; Gómez-Elvira, Javier; Gondet, Brigitte; Gordon, Suzanne; Gorevan, Stephen; Grant, John; Griffes, Jennifer; Grinspoon, David; Grotzinger, John; Guillemot, Philippe; Guo, Jingnan; Gupta, Sanjeev; Guzewich, Scott; Haberle, Robert; Halleaux, Douglas; Hallet, Bernard; Hamilton, Vicky; Hardgrove, Craig; Harker, David; Harpold, Daniel; Harri, Ari-Matti; Harshman, Karl; Hassler, Donald; Haukka, Harri; Hayes, Alex; Herkenhoff, Ken; Herrera, Paul; Hettrich, Sebastian; Heydari, Ezat; Hipkin, Victoria; Hoehler, Tori; Hollingsworth, Jeff; Hudgins, Judy; Huntress, Wesley; Hurowitz, Joel; Hviid, Stubbe; Iagnemma, Karl; Indyk, Steve; Israël, Guy; Jackson, Ryan; Jacob, Samantha; Jakosky, Bruce; Jensen, Elsa; Jensen, Jaqueline Kløvgaard; Johnson, Jeffrey; Johnson, Micah; Johnstone, Steve; Jones, Andrea; Jones, John; Joseph, Jonathan; Jun, Insoo; Kah, Linda; Kahanpää, Henrik; Kahre, Melinda; Karpushkina, Natalya; Kasprzak, Wayne; Kauhanen, Janne; Keely, Leslie; Kemppinen, Osku; Keymeulen, Didier; Kim, Myung-Hee; Kinch, Kjartan; King, Penny; Kirkland, Laurel; Kocurek, Gary; Koefoed, Asmus; Köhler, Jan; Kortmann, Onno; Kozyrev, Alexander; Krezoski, Jill; Krysak, Daniel; Kuzmin, Ruslan; Lacour, Jean Luc; Lafaille, Vivian; Langevin, Yves; Lanza, Nina; Lasue, Jeremie; Le Mouélic, Stéphane; Lee, Ella Mae; Lee, Qiu-Mei; Lees, David; Lefavor, Matthew; Lemmon, Mark; Malvitte, Alain Lepinette; Leshin, Laurie; Léveillé, Richard; Lewin-Carpintier, Éric; Lewis, Kevin; Li, Shuai; Lipkaman, Leslie; Little, Cynthia; Litvak, Maxim; Lorigny, Eric; Lugmair, Guenter; Lundberg, Angela; Lyness, Eric; Madsen, Morten; Mahaffy, Paul; Maki, Justin; Malakhov, Alexey; Malespin, Charles; Malin, Michael; Mangold, Nicolas; Manhes, Gérard; Manning, Heidi; Marchand, Geneviève; Jiménez, Mercedes Marín; García, César Martín; Martin, Dave; Martin, Mildred; Martínez-Frías, Jesús; Martín-Soler, Javier; Martín-Torres, F. Javier; Mauchien, Patrick; Maurice, Sylvestre; McAdam, Amy; McCartney, Elaina; McConnochie, Timothy; McCullough, Emily; McEwan, Ian; McKay, Christopher; McLennan, Scott; McNair, Sean; Melikechi, Noureddine; Meslin, Pierre-Yves; Meyer, Michael; Mezzacappa, Alissa; Miller, Hayden; Miller, Kristen; Milliken, Ralph; Ming, Douglas; Minitti, Michelle; Mischna, Michael; Mitrofanov, Igor; Moersch, Jeff; Mokrousov, Maxim; Jurado, Antonio Molina; Moores, John; Mora-Sotomayor, Luis; Morookian, John Michael; Morris, Richard; Morrison, Shaunna; Mueller-Mellin, Reinhold; Muller, Jan-Peter; Caro, Guillermo Muñoz; Nachon, Marion; López, Sara Navarro; Navarro-González, Rafael; Nealson, Kenneth; Nefian, Ara; Nelson, Tony; Newcombe, Megan; Newman, Claire; Newsom, Horton; Nikiforov, Sergey; Niles, Paul; Nixon, Brian; Dobrea, Eldar Noe; Nolan, Thomas; Oehler, Dorothy; Ollila, Ann; Olson, Timothy; Owen, Tobias; Hernández, Miguel Ángel de Pablo; Paillet, Alexis; Pallier, Etienne; Palucis, Marisa; Parker, Timothy; Parot, Yann; Patel, Kiran; Paton, Mark; Paulsen, Gale; Pavlov, Alex; Pavri, Betina; Peinado-González, Verónica; Pepin, Robert; Peret, Laurent; Perez, Rene; Perrett, Glynis; Peterson, Joe; Pilorget, Cedric; Pinet, Patrick; Pla-García, Jorge; Plante, Ianik; Poitrasson, Franck; Polkko, Jouni; Popa, Radu; Posiolova, Liliya; Posner, Arik; Pradler, Irina; Prats, Benito; Prokhorov, Vasily; Purdy, Sharon Wilson; Raaen, Eric; Radziemski, Leon; Rafkin, Scot; Ramos, Miguel; Rampe, Elizabeth; Raulin, François; Ravine, Michael; Reitz, Günther; Rennó, Nilton; Rice, Melissa; Richardson, Mark; Robert, François; Robertson, Kevin; Manfredi, José Antonio Rodriguez; Romeral-Planelló, Julio J.; Rowland, Scott; Rubin, David; Saccoccio, Muriel; Salamon, Andrew; Sandoval, Jennifer; Sanin, Anton; Fuentes, Sara Alejandra Sans; Saper, Lee; Sarrazin, Philippe; Sautter, Violaine; Savijärvi, Hannu; Schieber, Juergen; Schmidt, Mariek; Schmidt, Walter; Scholes, Daniel "Dan"; Schoppers, Marcel; Schröder, Susanne; Schwenzer, Susanne; Martinez, Eduardo Sebastian; Sengstacken, Aaron; Shterts, Ruslan; Siebach, Kirsten; Siili, Tero; Simmonds, Jeff; Sirven, Jean-Baptiste; Slavney, Susie; Sletten, Ronald; Smith, Michael; Sánchez, Pablo Sobrón; Spanovich, Nicole; Spray, John; Squyres, Steven; Stack, Katie; Stalport, Fabien; Steele, Andrew; Stein, Thomas; Stern, Jennifer; Stewart, Noel; Stipp, Susan Louise Svane; Stoiber, Kevin; Stolper, Ed; Sucharski, Bob; Sullivan, Rob; Summons, Roger; Sumner, Dawn; Sun, Vivian; Supulver, Kimberley; Sutter, Brad; Szopa, Cyril; Tan, Florence; Tate, Christopher; Teinturier, Samuel; ten Kate, Inge; Thomas, Peter; Thompson, Lucy; Tokar, Robert; Toplis, Mike; Redondo, Josefina Torres; Trainer, Melissa; Treiman, Allan; Tretyakov, Vladislav; Urqui-O'Callaghan, Roser; Van Beek, Jason; Van Beek, Tessa; VanBommel, Scott; Vaniman, David; Varenikov, Alexey; Vasavada, Ashwin; Vasconcelos, Paulo; Vicenzi, Edward; Vostrukhin, Andrey; Voytek, Mary; Wadhwa, Meenakshi; Ward, Jennifer; Webster, Chris; Weigle, Eddie; Wellington, Danika; Westall, Frances; Wiens, Roger Craig; Wilhelm, Mary Beth; Williams, Amy; Williams, Joshua; Williams, Rebecca; Williams, Richard B. "Mouser"; Wilson, Mike; Wimmer-Schweingruber, Robert; Wolff, Mike; Wong, Mike; Wray, James; Wu, Megan; Yana, Charles; Yen, Albert; Yingst, Aileen; Zeitlin, Cary; Zimdar, Robert; Mier, María-Paz Zorzano

    2013-09-01

    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, 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 Fe3+- 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.

  15. Time-, frequency-, and wavevector-resolved x-ray diffraction from single molecules

    PubMed Central

    Bennett, Kochise; Biggs, Jason D.; Zhang, Yu; Dorfman, Konstantin E.; Mukamel, Shaul

    2014-01-01

    Using a quantum electrodynamic framework, we calculate the off-resonant scattering of a broadband X-ray pulse from a sample initially prepared in an arbitrary superposition of electronic states. The signal consists of single-particle (incoherent) and two-particle (coherent) contributions that carry different particle form factors that involve different material transitions. Single-molecule experiments involving incoherent scattering are more influenced by inelastic processes compared to bulk measurements. The conditions under which the technique directly measures charge densities (and can be considered as diffraction) as opposed to correlation functions of the charge-density are specified. The results are illustrated with time- and wavevector-resolved signals from a single amino acid molecule (cysteine) following an impulsive excitation by a stimulated X-ray Raman process resonant with the sulfur K-edge. Our theory and simulations can guide future experimental studies on the structures of nano-particles and proteins. PMID:24880284

  16. Pseudomonoenergetic x-ray diffraction measurements using balanced filters for coherent-scatter computed tomography

    SciTech Connect

    Beath, S. R.; Cunningham, I. A.

    2009-05-15

    Coherent-scatter computed tomography (CSCT) is a method of ''composition'' imaging based on measurements of diffraction patterns from tissues. Use of an x-ray tube degrades scatter pattern angular resolution due to the x-ray spectral width, making it difficult to uniquely identify some materials. The use of two transmission filters with similar atomic numbers (balanced ''Ross filters'') to generate pseudomonoenergetic scatter patterns is described as it applies to CSCT. An analysis of angular-blur mechanisms reveals that focal spot size and beam width are the most important factors determining Bragg-peak width when Er-Tm filters are used. A relative RMS spectral width of 1% can be achieved in the difference spectrum and a Bragg-peak RMS angular width of approximately 0.14 deg. (relative width of 3% at 5 deg. scatter angle) can be achieved with an effective energy of 58 keV.

  17. RASOR: an advanced instrument for soft x-ray reflectivity and diffraction.

    PubMed

    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. PMID:20687739

  18. Automated high pressure cell for pressure jump x-ray diffraction

    SciTech Connect

    Brooks, Nicholas J.; Gauthe, Beatrice L. L. E.; Templer, Richard H.; Ces, Oscar; Seddon, John M.; Terrill, Nick J.; Rogers, Sarah E.

    2010-06-15

    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.

  19. On radiation damage in FIB-prepared softwood samples measured by scanning X-ray diffraction.

    PubMed

    Storm, Selina; Ogurreck, Malte; Laipple, Daniel; Krywka, Christina; Burghammer, Manfred; Di Cola, Emanuela; Müller, Martin

    2015-03-01

    The high flux density encountered in scanning X-ray nanodiffraction experiments can lead to severe radiation damage to biological samples. However, this technique is a suitable tool for investigating samples to high spatial resolution. The layered cell wall structure of softwood tracheids is an interesting system which has been extensively studied using this method. The tracheid cell has a complex geometry, which requires the sample to be prepared by cutting it perpendicularly to the cell wall axis. Focused ion beam (FIB) milling in combination with scanning electron microscopy allows precise alignment and cutting without splintering. Here, results of a scanning X-ray diffraction experiment performed on a biological sample prepared with a focused ion beam of gallium atoms are reported for the first time. It is shown that samples prepared and measured in this way suffer from the incorporation of gallium atoms up to a surprisingly large depth of 1 µm. PMID:25723928

  20. Structural studies of PCU-hydrazones: NMR spectroscopy, X-ray diffractions, and DFT calculations

    NASA Astrophysics Data System (ADS)

    Veljković, Jelena; Šekutor, Marina; Molčanov, Krešimir; Lo, Rabindranath; Ganguly, Bishwajit; Mlinarić-Majerski, Kata

    2011-06-01

    In this article we present a detailed structural investigation for the configurational isomers of PCU-hydrazones. The structural characterization of these hydrazones was performed using NMR spectroscopy, X-ray diffraction analysis and theoretical calculations. The single crystal X-ray structures of PCU-hydrazones 6B and 6C have been solved and used to conclusively confirm the characterization obtained via NMR spectra of a particular isomer. Nuclear magnetic shielding values calculated for 6A-C using DFT calculations were correlated with the experimentally determined chemical shifts. The computed results were found to be in good agreement with the observed 13C NMR values. The computed NMR results helped to ascertain the isomers of PCU-hydrazones 4A-C.

  1. High-Angular-Resolution Microbeam X-Ray Diffraction with CCD Detector

    SciTech Connect

    Imai, Yasuhiko; Kimura, Shigeru; Sakaia, Akira; Sakata, Osami

    2010-04-06

    We have introduced a CCD-type two-dimensional X-ray detector for a microbeam X-ray diffraction system using synchrotron radiation, so that we can measure local reciprocal space maps (RSM) of samples rapidly. A local RSM of a strain-relaxed SiGe 004 grown on a Si (001) substrate was measured in higher-angular-resolution and faster than a conventional way. The measurement was achieved in 1 h 40 min. with the 2theta resolution of 80 murad and the spatial resolution of 1.4(h)x0.5(v) {mu}m{sup 2}. The introduction of the CCD enabled us to measure RSMs at many points in a sample, that is, the distribution of strain fields and lattice tilts can be revealed in high-angular- and high-spatial-resolution.

  2. X-ray diffraction results from Mars Science Laboratory: mineralogy of Rocknest at Gale crater.

    PubMed

    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. PMID:24072925

  3. Time-, frequency-, and wavevector-resolved x-ray diffraction from single molecules

    SciTech Connect

    Bennett, Kochise Biggs, Jason D.; Zhang, Yu; Dorfman, Konstantin E.; Mukamel, Shaul

    2014-05-28

    Using a quantum electrodynamic framework, we calculate the off-resonant scattering of a broadband X-ray pulse from a sample initially prepared in an arbitrary superposition of electronic states. The signal consists of single-particle (incoherent) and two-particle (coherent) contributions that carry different particle form factors that involve different material transitions. Single-molecule experiments involving incoherent scattering are more influenced by inelastic processes compared to bulk measurements. The conditions under which the technique directly measures charge densities (and can be considered as diffraction) as opposed to correlation functions of the charge-density are specified. The results are illustrated with time- and wavevector-resolved signals from a single amino acid molecule (cysteine) following an impulsive excitation by a stimulated X-ray Raman process resonant with the sulfur K-edge. Our theory and simulations can guide future experimental studies on the structures of nano-particles and proteins.

  4. Data preparation and evaluation techniques for x-ray diffraction microscopy

    SciTech Connect

    Steinbrener, Jan; Nelson, Johanna; Huang, Xiaojing; Marchesini, Stefano; Shapiro, David; Turner, Joshua J.; Jacobsen, Chris

    2010-01-01

    The post-experiment processing of X-ray Diffraction Microscopy data is often time-consuming and difficult. This is mostly due to the fact that even if a preliminary result has been reconstructed, there is no definitive answer as to whether or not a better result with more consistently retrieved phases can still be obtained. In addition, we show here that the first step in data analysis, the assembly of two-dimensional diffraction patterns from a large set of raw diffraction data, is crucial to obtaining reconstructions of highest possible consistency. We have developed software that automates this process and results in consistently accurate diffraction patterns. We have furthermore derived some criteria of validity for a tool commonly used to assess the consistency of reconstructions, the phase retrieval transfer function, and suggest a modified version that has improved utility for judging reconstruction quality.

  5. Probing local order in glasses from limited-volume electron and x-ray diffraction

    NASA Astrophysics Data System (ADS)

    Liu, A. C. Y.; Tabor, R. F.; Bourgeois, L.; de Jonge, M. D.; Mudie, S. T.; Petersen, T. C.

    2016-05-01

    It has long been recognised that spatial fluctuations in local order in disordered assemblies of particles can be probed using limited-volume diffraction measurements. These measurements have unique advantages over broad-beam diffraction experiments that isotropically average over many structural configurations and result in one-dimensional intensity curves, requiring modelling to interpret. Despite the advantages of limiting illumination to a low number of particle configurations, obtaining quantitative measurements of local order from such experiments remains a challenge. The effects on the diffraction pattern of changing the beam energy, lateral size, aberrations and coherence and the specimen thickness have only recently been clarified. We review theoretical and experimental efforts in this direction in the fields of both electron and x-ray diffraction and identify promising areas of future development.

  6. Imaging at the X-ray Frontier: Coherent Diffraction Imaging (CDI) for Nano and Bioscience

    NASA Astrophysics Data System (ADS)

    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.

  7. Diffraction-Based Techniques For High Contrast X-ray Imaging

    NASA Astrophysics Data System (ADS)

    Peerzada, Lubna Naseem

    Two X-ray diffraction based techniques for high contrast were explored to improve contrast in radiology: diffraction enhanced imaging (DEI) and coherent scatter imaging. DEI produces contrast in images based upon the difference in the X-ray refractive indices of materials or tissues. Two DEI systems were devised. Both were comprised of a conventional polychromatic copper X-ray source, polycapillary collimating optics and two silicon crystals.Lucite step phantoms and nylon tubing were imaged. No fringe effects were observed. The lack of observable edge enhancement may have been due to the optic structure which obscured refraction effects. Better results might have been achieved if a higher resolution detector or phantom of larger step size or larger diameter thin walled tubing had been used. The second technique was coherent scatter X-ray imaging. The purpose of this work was to differentiate between healthy and diseased human breast tissues. For instance, breast carcinoma is known to have a peak coherent scattering angle at 12.2° for Mo Ka radiation at 17.5 keV, whereas fatty tissue peaks around 9°. A system which would be compatible with screening mammography was developed. The system was expanded to include sample scanning to allow for a larger image area. The modulation transfer function was computed for static and scanned images of a resolution phantom. These showed good agreement, indicating that the scanning was properly aligned and timed. Static and scanned images of phantoms were taken and the contrast was calculated for a series of experimental parameters including, grid tilt angle. A complex phantom was also then imaged. It was possible to distinguish tissue-equivalent phantom types. Good contrast resolution scanned images were obtained which is promising for a diagnostic system.

  8. KOTOBUKI-1 apparatus for cryogenic coherent X-ray diffraction imaging

    NASA Astrophysics Data System (ADS)

    Nakasako, Masayoshi; Takayama, Yuki; Oroguchi, Tomotaka; Sekiguchi, Yuki; Kobayashi, Amane; Shirahama, Keiya; Yamamoto, Masaki; Hikima, Takaaki; Yonekura, Koji; Maki-Yonekura, Saori; Kohmura, Yoshiki; Inubushi, Yuichi; Takahashi, Yukio; Suzuki, Akihiro; Matsunaga, Sachihiro; Inui, Yayoi; Tono, Kensuke; Kameshima, Takashi; Joti, Yasumasa; Hoshi, Takahiko

    2013-09-01

    We have developed an experimental apparatus named KOTOBUKI-1 for use in coherent X-ray diffraction imaging experiments of frozen-hydrated non-crystalline particles at cryogenic temperature. For cryogenic specimen stage with small positional fluctuation for a long exposure time of more than several minutes, we here use a cryogenic pot cooled by the evaporation cooling effect for liquid nitrogen. In addition, a loading device is developed to bring specimens stored in liquid nitrogen to the specimen stage in vacuum. The apparatus allows diffraction data collection for frozen-hydrated specimens at 66 K with a positional fluctuation of less than 0.4 μm and provides an experimental environment to easily exchange specimens from liquid nitrogen storage to the specimen stage. The apparatus was developed and utilized in diffraction data collection of non-crystalline particles with dimensions of μm from material and biological sciences, such as metal colloid particles and chloroplast, at BL29XU of SPring-8. Recently, it has been applied for single-shot diffraction data collection of non-crystalline particles with dimensions of sub-μm using X-ray free electron laser at BL3 of SACLA.

  9. KOTOBUKI-1 apparatus for cryogenic coherent X-ray diffraction imaging

    SciTech Connect

    Nakasako, Masayoshi; Takayama, Yuki; Oroguchi, Tomotaka; Sekiguchi, Yuki; Kobayashi, Amane; Shirahama, Keiya; Yamamoto, Masaki; Hikima, Takaaki; Yonekura, Koji; Maki-Yonekura, Saori; Kohmura, Yoshiki; Inubushi, Yuichi; Takahashi, Yukio; Suzuki, Akihiro; Matsunaga, Sachihiro; Inui, Yayoi; Tono, Kensuke; Kameshima, Takashi; Joti, Yasumasa; Hoshi, Takahiko

    2013-09-15

    We have developed an experimental apparatus named KOTOBUKI-1 for use in coherent X-ray diffraction imaging experiments of frozen-hydrated non-crystalline particles at cryogenic temperature. For cryogenic specimen stage with small positional fluctuation for a long exposure time of more than several minutes, we here use a cryogenic pot cooled by the evaporation cooling effect for liquid nitrogen. In addition, a loading device is developed to bring specimens stored in liquid nitrogen to the specimen stage in vacuum. The apparatus allows diffraction data collection for frozen-hydrated specimens at 66 K with a positional fluctuation of less than 0.4 μm and provides an experimental environment to easily exchange specimens from liquid nitrogen storage to the specimen stage. The apparatus was developed and utilized in diffraction data collection of non-crystalline particles with dimensions of μm from material and biological sciences, such as metal colloid particles and chloroplast, at BL29XU of SPring-8. Recently, it has been applied for single-shot diffraction data collection of non-crystalline particles with dimensions of sub-μm using X-ray free electron laser at BL3 of SACLA.

  10. Theory of radial X-ray Diffraction from a Polycrystalline Sample Undergoing Plastic Deformation

    SciTech Connect

    S Karato

    2011-12-31

    Theory of lattice strain in a polycrystalline aggregate under deviatoric stress is extended to include the influence of ongoing plastic deformation. When deviatoric stress is applied to a polycrystalline material at high temperatures (or above the yield stress), applied macroscopic stress is redistributed to individual grains by plastic deformation according to their orientations with respect to the macroscopic stress and plastic anisotropy of a given crystal. This microstress causes elastic deformation of individual grains that can be measured by x-ray diffraction. Consequently, the observed lattice strain depends on two material properties, viscosity (plasticity) and elastic compliance as well as the applied macroscopic stress and the stress-strain distribution among various grains. The influence of plastic deformation on lattice strain is analyzed using an anisotropic and nonlinear power-law constitutive relationship. In this model, the dependence of inferred macroscopic stress on the crystallographic orientation of diffraction plane (hkl) comes from elastic and plastic anisotropy of a crystal. In many materials, plastic anisotropy dominates over elastic anisotropy. This explains the observed large dependence of inferred stress on the diffraction plane and means that the determination of elastic anisotropy is difficult when plastic deformation occurs with anisotropic plasticity. When elastic anisotropy is known, plastic anisotropy of single crystal and/or stress-strain distribution in a deformed polycrystal can be determined from radial x-ray diffraction using the present model. Some examples are presented using the data on MgO.

  11. X-ray diffraction study of short-period AlN/GaN superlattices

    SciTech Connect

    Kyutt, R. N. Shcheglov, M. P.; Ratnikov, V. V.; Yagovkina, M. A.; Davydov, V. Yu.; Smirnov, A. N.; Rozhavskaya, M. M.; Zavarin, E. E.; Lundin, V. V.

    2013-12-15

    The structure of short-period hexagonal GaN/AlN superlattices (SLs) has been investigated by X-ray diffraction. The samples have been grown by metalorganic vapor-phase epitaxy (MOVPE) in a horizontal reactor at a temperature of 1050°C on (0001)Al{sub 2}O{sub 3} substrates using GaN and AlN buffer layers. The SL period changes from 2 to 6 nm, and the thickness of the structure varies in a range from 0.3 to 1 μm. The complex of X-ray diffraction techniques includes a measurement of θ-2θ rocking curves of symmetric Bragg reflection, the construction of intensity maps for asymmetric reflections, a measurement and analysis of peak broadenings in different diffraction geometries, a precise measurement of lattice parameters, and the determination of radii of curvature. The thickness and strain of separate SL layers are determined by measuring the θ-2θ rocking curves subsequent simulation. It is shown that most SL samples are completely relaxed as a whole. At the same time, relaxation is absent between sublayers, which is why strains in the AlN and GaN sublayers (on the order of 1.2 × 10{sup −2}) have different signs. An analysis of diffraction peak half-widths allows us to determine the densities of individual sets of dislocations and observe their change from buffer layers to SLs.

  12. Vibrational Spectroscopy and X-ray Diffraction of Cd(OH)2 to 28GPa at 300 K

    SciTech Connect

    Shim, Sang-Heon; Rekhi, Sandeep; Martin, Michael C.; Jeanloz,Raymond

    2006-03-20

    We report Raman and infrared absorption spectroscopy alongwith X-ray diffraction for brucite-type beta-Cd(OH)2 to 28 GPa at 300 K.The OH-stretching modes soften with pressure and disappear at 21 GPa withtheir widths increasing rapidly above 5 GPa, consistent with a gradualdisordering of the H sublattice at 5 20 GPa similar to that previouslyobserved for Co(OH)2.Asymmetry in the peak shapes of the OH-stretchingmodes suggests the existence of diverse disordered sitesfor H atoms inCd(OH)2 under pressure. Above 15 GPa, the A1g(T) lattice mode showsnon-linear behavior and softens to 21 GPa, at which pressure significantchanges are observed: new Raman modes appear, two Raman-active latticemodes and the OH-stretching modes of the low-pressure phase disappears,and the positions of some X-ray diffraction lines change abruptly withthe appearance of weak new diffraction features. These observationssuggest that amorphization of the H sublattice is accompanied by acrystalline-to-crystalline transition at 21 GPa in Cd(OH)2, which has notbeen previously observed in the brucite-type hydroxides. The Ramanspectra of the high-pressure phase of Cd(OH)2 is similar to those of thehigh-pressure phase of single-crystal Ca(OH)2 of which structure has beententatively assigned to the Sr(OH)2 type.

  13. A high-transparency, micro-patternable chip for X-ray diffraction analysis of microcrystals under native growth conditions

    SciTech Connect

    Murray, Thomas D.; Lyubimov, Artem Y.; Ogata, Craig M.; Vo, Huy; Uervirojnangkoorn, Monarin; Brunger, Axel T.; Berger, James M.

    2015-09-26

    A highly X-ray-transparent, silicon nitride-based device has been designed and fabricated to harvest protein microcrystals for high-resolution X-ray diffraction data collection using microfocus beamlines and XFELs. Microcrystals present a significant impediment to the determination of macromolecular structures by X-ray diffraction methods. Although microfocus synchrotron beamlines and X-ray free-electron lasers (XFELs) can enable the collection of interpretable diffraction data from microcrystals, there is a need for efficient methods of harvesting small volumes (<2 µl) of microcrystals grown under common laboratory formats and delivering them to an X-ray beam source under native growth conditions. One approach that shows promise in overcoming the challenges intrinsic to microcrystal analysis is to pair so-called ‘fixed-target’ sample-delivery devices with microbeam-based X-ray diffraction methods. However, to record weak diffraction patterns it is necessary to fabricate devices from X-ray-transparent materials that minimize background scattering. Presented here is the design of a new micro-diffraction device consisting of three layers fabricated from silicon nitride, photoresist and polyimide film. The chip features low X-ray scattering and X-ray absorption properties, and uses a customizable blend of hydrophobic and hydrophilic surface patterns to help localize microcrystals to defined regions. Microcrystals in their native growth conditions can be loaded into the chips with a standard pipette, allowing data collection at room temperature. Diffraction data collected from hen egg-white lysozyme microcrystals (10–15 µm) loaded into the chips yielded a complete, high-resolution (<1.6 Å) data set sufficient to determine a high-quality structure by molecular replacement. The features of the chip allow the rapid and user-friendly analysis of microcrystals grown under virtually any laboratory format at microfocus synchrotron beamlines and XFELs.

  14. A new bend magnet beam line for scanning transmission x-ray microscopy at the Advanced Light Source

    SciTech Connect

    Warwick, Tony; Ade, Harald; Kilcoyne, A.L. David; Kritscher, Michael; Tylisczcak, Tolek; Fakra, Sirine; Hitchcock, Adam P.; Hitchcock, Peter; Padmore, Howard A.

    2001-12-12

    The high brightness of the bend magnets at the Advanced Light Source has been exploited to illuminate a Scanning Transmission X-ray Microscope (STXM). This is the first diffraction-limited scanning x-ray microscope to operate with useful count rate on a synchrotron bend magnet source. A simple, dedicated beam line has been built covering the range of photon energy from 250 eV to 600 eV. Ease of use and operational availability are radically improved compared to previous installations using undulator beams. This facility provides radiation for C 1s, N 1s and O 1s near edge x-ray absorption spectro-microscopy with a spectral resolution up to about 1:5000 and with STXM count rates in excess of 1 MHz.

  15. Structure-function Investigation of Operando Nanostructured Materials Using Coherent X-ray Diffractive Imaging

    NASA Astrophysics Data System (ADS)

    Ulvestad, Andrew

    Nanostructured devices promise to help solve grand challenges of our time, including renewable energy generation, storage, and mitigating climate change. Their power lies in the particular influence of the surface on the total free energy when dimensions approach the nanoscale and it is well known that different sizes, shapes, and defects can drastically alter material properties. However, this strength represents a considerable challenge for imaging techniques that can be limited in terms of sample environments, average over large ensembles of particles, and/or lack adequate spatiotemporal resolution for studying the relevant physical processes. The focus of this thesis is the development of in situ coherent X-ray diffractive imaging (CXDI) and its application in imaging strain evolution in battery cathode nanoparticles. Using in situ CXDI, the compressive/tensile strain field in the pristine state is revealed, and found to be linked to a particular concentration of strain inducing Jahn-Teller ions. The evolution of strain during the first charge/discharge cycle shows that the cathode nanoparticle exhibits phase separation. Using the 3D strain field, the strain field energy is calculated and shows interesting hysteresis between charge and discharge. Strain evolution during a disconnection event, in which the cathode nanoparticle is no longer able to exchange electrons and ions with its environment, reveals the formation of a poorly conducting interphase layer. Finally, strain fields were used to study dislocation dynamics in battery nanoparticles. Using the full 3D information, the dislocation line structure is mapped and shown to move in response to charge transfer. The dislocation is used as a way to probe the local material properties and it is discovered that the material enters an ``auxetic", or negative Poisson's ratio, regime.

  16. Analysis of energy dispersive x-ray diffraction profiles for material identification, imaging and system control

    NASA Astrophysics Data System (ADS)

    Cook, Emily Jane

    2008-12-01

    This thesis presents the analysis of low angle X-ray scatter measurements taken with an energy dispersive system for substance identification, imaging and system control. Diffraction measurements were made on illicit drugs, which have pseudo- crystalline structures and thus produce diffraction patterns comprising a se ries of sharp peaks. Though the diffraction profiles of each drug are visually characteristic, automated detection systems require a substance identification algorithm, and multivariate analysis was selected as suitable. The software was trained with measured diffraction data from 60 samples covering 7 illicit drugs and 5 common cutting agents, collected with a range of statistical qual ities and used to predict the content of 7 unknown samples. In all cases the constituents were identified correctly and the contents predicted to within 15%. Soft tissues exhibit broad peaks in their diffraction patterns. Diffraction data were collected from formalin fixed breast tissue samples and used to gen erate images. Maximum contrast between healthy and suspicious regions was achieved using momentum transfer windows 1.04-1.10 and 1.84-1.90 nm_1. The resulting images had an average contrast of 24.6% and 38.9% compared to the corresponding transmission X-ray images (18.3%). The data was used to simulate the feedback for an adaptive imaging system and the ratio of the aforementioned momentum transfer regions found to be an excellent pa rameter. Investigation into the effects of formalin fixation on human breast tissue and animal tissue equivalents indicated that fixation in standard 10% buffered formalin does not alter the diffraction profiles of tissue in the mo mentum transfer regions examined, though 100% unbuffered formalin affects the profile of porcine muscle tissue (a substitute for glandular and tumourous tissue), though fat is unaffected.

  17. UV and X-ray variability of the narrow-line Seyfert 1 galaxy Ark 564

    NASA Astrophysics Data System (ADS)

    Ezhikode, Savithri H.; Dewangan, Gulab C.; Misra, Ranjeev; Tripathi, Shruti; Sajeeth Philip, Ninan; Kembhavi, Ajit K.

    2016-07-01

    We analyze eight XMM-Newton observations of the bright Narrow Line Seyfert 1 galaxy Arakelian 564 (Ark 564). These observations, separated by ∼ 6 days, allow us to look for correlations between the simultaneous ultraviolet (UV) emission (from the Optical Monitor) with not only the X-ray flux but also with different X-ray spectral parameters. The X-ray spectra from all the observations are found to be adequately fitted by a double Comptonization model where the soft excess and the hard X-ray power law are represented by thermal Comptonization in a low temperature plasma and hot corona, respectively. Apart from the fluxes of each component, the hard X-ray power law index is found to be variable. These results suggest that the variability is associated with changes in the geometry of the inner region. The UV emission is found to be variable and well correlated with the high energy index while the correlations with the fluxes of each component are found to be weaker. Using viscous timescale arguments we rule out the possibility that the UV variation is due to the fluctuating accretion rate in the outer disk. If the UV variation is driven by X-ray reprocessing, then our results indicate that the strength of the X-ray reprocessing depends more on the geometry of the X-ray producing inner region rather than on the X-ray luminosity alone.

  18. Discovery of an X-ray Violently Variable Broad Absorption Line Quasar

    NASA Technical Reports Server (NTRS)

    Ghosh, Kajal K.; Gutierrez, Carlos M.; Punsly, Brian; Chevallier, Loic; Goncalves, Anabela C.

    2006-01-01

    In this letter, we report on a quasar that is violently variable in the X-rays, XVV. It is also a broad absorption line quasar (BALQSO) that exhibits both high ionization and low ionization UV absorption lines (LoBALQSO). It is very luminous in the X-rays (approximately 10(exp 46) ergs s(sup -l) over the entire X-ray band). Surprisingly, this does not over ionize the LoBAL outflow. The X-rays vary by a factor of two within minutes in the quasar rest frame, which is shorter than 1/30 of the light travel time across a scale length equal to the black hole radius. We concluded that the X-rays are produced in a relativistic jet beamed toward earth in which variations in the Doppler enhancement produce the XVV behavior.

  19. Structure of ZnO Nanorods using X-ray Diffraction

    SciTech Connect

    Howdyshell, Marci; /Albion Coll. /SLAC

    2007-11-07

    Many properties of zinc oxide, including wide bandgap semiconductivity, photoconductivity, and chemical sensing, make it a very promising material for areas such as optoelectronics and sensors. This research involves analysis of the formation, or nucleation, of zinc oxide by electrochemical deposition in order to gain a better understanding of the effect of different controlled parameters on the subsequently formed nanostructures. Electrochemical deposition involves the application of a potential to an electrolytic solution containing the species of interest, which causes the ions within to precipitate on one of the electrodes. While there are other ways of forming zinc oxide, this particular process is done at relatively low temperatures, and with the high amount of x-ray flux available at SSRL it is possible to observe such nucleation in situ. Additionally, several parameters can be controlled using the x-ray synchrotron; the concentration of Zn{sup 2+} and the potential applied were controlled during this project. The research involved both gathering the X-ray diffraction data on SSRL beamline 11-3, and analyzing it using fit2d, Origin 6.0 and Microsoft Excel. A time series showed that both the in-plane and out-of-plane components of the ZnO nanorods grew steadily at approximately the same rate throughout deposition. Additionally, analysis of post-scans showed that as potential goes from less negative to more negative, the resulting nanostructures become more oriented.

  20. Tracking the motion of charges in a terahertz light field by femtosecond X-ray diffraction.

    PubMed

    Cavalleri, A; Wall, S; Simpson, C; Statz, E; Ward, D W; Nelson, K A; Rini, M; Schoenlein, R W

    2006-08-10

    In condensed matter, light propagation near resonances is described in terms of polaritons, electro-mechanical excitations in which the time-dependent electric field is coupled to the oscillation of charged masses. This description underpins our understanding of the macroscopic optical properties of solids, liquids and plasmas, as well as of their dispersion with frequency. In ferroelectric materials, terahertz radiation propagates by driving infrared-active lattice vibrations, resulting in phonon-polariton waves. Electro-optic sampling with femtosecond optical pulses can measure the time-dependent electrical polarization, providing a phase-sensitive analogue to optical Raman scattering. Here we use femtosecond time-resolved X-ray diffraction, a phase-sensitive analogue to inelastic X-ray scattering, to measure the corresponding displacements of ions in ferroelectric lithium tantalate, LiTaO(3). Amplitude and phase of all degrees of freedom in a light field are thus directly measured in the time domain. Notably, extension of other X-ray techniques to the femtosecond timescale (for example, magnetic or anomalous scattering) would allow for studies in complex systems, where electric fields couple to multiple degrees of freedom. PMID:16900195

  1. Spontaneous soft x-ray fluorescence from a superlattice under Kossel diffraction conditions

    NASA Astrophysics Data System (ADS)

    Jonnard, P.; Yuan, Y.-Y.; Le Guen, K.; André, J.-M.; Zhu, J.-T.; Wang, Z.-S.; Bridou, F.

    2014-08-01

    The present study gives the proof of principle of a technique that is an extension of Kossel diffraction both from crystals to superlattices and toward the soft x-ray region, allowing the characterization of the interfaces within a periodic structure. We measure the intensity of the Co Lα and Mg Kα characteristic fluorescence emissions from a Mg/Co superlattice upon soft x-ray excitation. The observation is made so that the angle between the sample surface and the detection direction is scanned around the first and second Bragg peaks of the fluorescence emissions. Clear modulations of the emitted intensities are observed and well reproduced by simulations based on the reciprocity theorem and assuming a perfect stack. The present work gives evidence that such a superlattice plays the role of an optical cavity for the spontaneous emission generated within the stack. This should also be the case for stimulated emission, which when combined with pumping free electron laser, will open the road to innovative x-ray distributed feedback lasers.

  2. Tracking the motion of charges in a terahertz light field byfemtosecond X-ray diffraction

    SciTech Connect

    Cavalleri, A.; Wall, S.; Simpson, C.; Statz, E.; Ward, D.W.; Nelson, K.A.; Rini, M.; Schoenlein, R.W.

    2006-07-01

    In condensed matter, light propagation near resonances isdescribed in terms of polaritons, electro-mechanical excitations in whichthe time-dependent electric field is coupled to the oscillation ofcharged masses. This description under pins our understanding of themacroscopic optical properties of solids, liquids and plasmas, as well asof their dispersion with frequency. In ferroelectric materials, terahertzradiation propagates by driving infrared-active lattice vibrations,resulting in phononpolariton waves. Electro-optic sampling withfemtosecond optical pulses can measure the time-dependent electricalpolarization, providing a phase-sensitive analogue to optical Ramanscattering. Here we use femtosecond time-resolved X-ray diffraction, aphase-sensitive analogue to inelastic X-ray scattering, to measure thecorresponding displacements of ions in ferroelectric lithium tantalate,LiTaO3. Amplitude and phase of all degrees of freedom in a light fieldare thus directly measured in the time domain. Notably, extension ofother X-ray techniques to the femtosecond timescale (for example,magnetic or anomalous scattering) would allow for studies in complexsystems, where electric fields couple to multiple degrees offreedom.

  3. Thermal, structural and diffraction analyses of a gallium-cooled x- ray monochromator

    SciTech Connect

    Rogers, C.S.; Macrander, A.T.; Mills, D.M.

    1992-06-01

    The next generation of synchrotron radiation sources will produce very high power and power density x-ray beams. For example, the Advanced Photon Source (APS) under construction at Argonne National Laboratory will produce beams containing up to 5 kill of power and peak normal power densities in excess of 150 W/mm{sup 2}. Normally, the first optical component to intercept the x-ray beam is a crystal monochromator. This device typically uses a single crystal of silicon or germanium as a band-pass filter according to Braggs` law of diffraction. Under the severe heat loading of modem synchrotron beams, the performance of the monochromator is degraded by reducing the photon throughput and increasing the beam divergence. This paper describes the methods used to calculate the thermally induced deformations in standardly configured monochromator crystals using finite element analysis. The results of these analyses are compared to recent experiments conducted at the Cornell High Energy Synchrotron Source (CHESS) using a high-performance, gallium-cooled crystal. Computer simulations can be used to evaluate the performance of high-heat-load x-ray optics for future synchrotron sources.

  4. Thermal, structural and diffraction analyses of a gallium-cooled x- ray monochromator

    SciTech Connect

    Rogers, C.S.; Macrander, A.T.; Mills, D.M.

    1992-06-01

    The next generation of synchrotron radiation sources will produce very high power and power density x-ray beams. For example, the Advanced Photon Source (APS) under construction at Argonne National Laboratory will produce beams containing up to 5 kill of power and peak normal power densities in excess of 150 W/mm{sup 2}. Normally, the first optical component to intercept the x-ray beam is a crystal monochromator. This device typically uses a single crystal of silicon or germanium as a band-pass filter according to Braggs' law of diffraction. Under the severe heat loading of modem synchrotron beams, the performance of the monochromator is degraded by reducing the photon throughput and increasing the beam divergence. This paper describes the methods used to calculate the thermally induced deformations in standardly configured monochromator crystals using finite element analysis. The results of these analyses are compared to recent experiments conducted at the Cornell High Energy Synchrotron Source (CHESS) using a high-performance, gallium-cooled crystal. Computer simulations can be used to evaluate the performance of high-heat-load x-ray optics for future synchrotron sources.

  5. Ab initio simulation of diffractometer instrumental function for high-resolution X-ray diffraction1

    PubMed Central

    Mikhalychev, Alexander; Benediktovitch, Andrei; Ulyanenkova, Tatjana; Ulyanenkov, Alex

    2015-01-01

    Modeling of the X-ray diffractometer instrumental function for a given optics configuration is important both for planning experiments and for the analysis of measured data. A fast and universal method for instrumental function simulation, suitable for fully automated computer realization and describing both coplanar and noncoplanar measurement geometries for any combination of X-ray optical elements, is proposed. The method can be identified as semi-analytical backward ray tracing and is based on the calculation of a detected signal as an integral of X-ray intensities for all the rays reaching the detector. The high speed of calculation is provided by the expressions for analytical integration over the spatial coordinates that describe the detection point. Consideration of the three-dimensional propagation of rays without restriction to the diffraction plane provides the applicability of the method for noncoplanar geometry and the accuracy for characterization of the signal from a two-dimensional detector. The correctness of the simulation algorithm is checked in the following two ways: by verifying the consistency of the calculated data with the patterns expected for certain simple limiting cases and by comparing measured reciprocal-space maps with the corresponding maps simulated by the proposed method for the same diffractometer configurations. Both kinds of tests demonstrate the agreement of the simulated instrumental function shape with the measured data. PMID:26089760

  6. Plutonium-uranium mixed oxide characterization by coupling micro-X-ray diffraction and absorption investigations

    NASA Astrophysics Data System (ADS)

    Degueldre, C.; Martin, M.; Kuri, G.; Grolimund, D.; Borca, C.

    2011-09-01

    Plutonium-uranium mixed oxide (MOX) fuels are currently used in nuclear reactors. The potential differences of metal redox state and microstructural developments of the matrix before and after irradiation are commonly analysed by electron probe microanalysis. In this work the structure and next-neighbor atomic environments of Pu and U oxide features within unirradiated homogeneous MOX and irradiated (60 MW d kg -1) MOX samples was analysed by micro-X-ray fluorescence (μ-XRF), micro-X-ray diffraction (μ-XRD) and micro-X-ray absorption fine structure (μ-XAFS) spectroscopy. The grain properties, chemical bonding, valences and stoichiometry of Pu and U are determined from the experimental data gained for the unirradiated as well as for irradiated fuel material examined in the center of the fuel as well as in its peripheral zone (rim). The formation of sub-grains is observed as well as their development from the center to the rim (polygonization). In the irradiated sample Pu remains tetravalent (>95%) and no (<5%) Pu(V) or Pu(VI) can be detected while the fuel could undergo slight oxidation in the rim zone. Any slight potential plutonium oxidation is buffered by the uranium dioxide matrix while locally fuel cladding interaction could also affect the redox of the fuel.

  7. X-ray laser diffraction for structure determination of the rhodopsin-arrestin complex

    DOE PAGESBeta

    Zhou, X. Edward; Gao, Xiang; Barty, Anton; Kang, Yanyong; He, Yuanzheng; Liu, Wei; Ishchenko, Andrii; White, Thomas A.; Yefanov, Oleksandr; Han, Gye Won; et al

    2016-04-12

    Here, serial femtosecond X-ray crystallography (SFX) using an X-ray free electron laser (XFEL) is a recent advancement in structural biology for solving crystal structures of challenging membrane proteins, including G-protein coupled receptors (GPCRs), which often only produce microcrystals. An XFEL delivers highly intense X-ray pulses of femtosecond duration short enough to enable the collection of single diffraction images before significant radiation damage to crystals sets in. Here we report the deposition of the XFEL data and provide further details on crystallization, XFEL data collection and analysis, structure determination, and the validation of the structural model. The rhodopsin-arrestin crystal structure solvedmore » with SFX represents the first near-atomic resolution structure of a GPCR-arrestin complex, provides structural insights into understanding of arrestin-mediated GPCR signaling, and demonstrates the great potential of this SFX-XFEL technology for accelerating crystal structure determination of challenging proteins and protein complexes.« less

  8. Cloning, expression, purification, crystallization and preliminary X-ray diffraction analysis of Rv2827c from Mycobacterium tuberculosis

    SciTech Connect

    Janowski, Robert

    2006-08-01

    M. tuberculosis hypothetical protein Rv2827c was cloned, expressed, purified and crystallized. Preliminary X-ray diffraction data were collected to a resolution of 1.93 Å. The hypothetical protein Rv2827c from Mycobacterium tuberculosis was cloned and heterologously expressed in Escherichia coli. It was purified using affinity and size-exclusion chromatographic techniques and then crystallized. Preliminary X-ray diffraction data analysis suggests the presence of two translationally related molecules in the asymmetric unit of the orthorhombic crystals.

  9. X-Ray Diffraction Microstructural Analysis of Bimodal-Size-Distribution MgO Nanopowders

    NASA Astrophysics Data System (ADS)

    Pratapa, Suminar; Hartono, Budi

    2010-01-01

    Investigation on the characteristics of x-ray diffraction data for MgO powdered mixture of nano and sub-nano particles has been carried out to reveal the crystallite-size-related microstructural information. The MgO powders were prepared by co-precipitation method followed by heat treatment at 500, 800 and 1200° C for 1 hour, being the difference in the temperature was to obtain two powders with distinct crystallite size and size-distribution. The powders were then carefully blended in air to give the presumably strain-free, bimodal-size-distribution MgO nanopowder. High-quality laboratory X-ray diffraction data for the powders were collected and then analysed using Rietveld-based MAUD software using the lognormal size distribution. Results show that the single-mode powders exhibit spherical crystallite size (Dv) of 29(1) nm, 36(1) and 185(0) nm for the 500, 800 and 1200° C data respectively with the nanometric powder displays slightly narrower crystallite size distribution character, indicated by lognormal dispersion parameter (σ) of 0.22 as compared to 0.18 for the sub-nanometric 1200° C powder. The mixture exhibits relatively more asymmetric peak broadening. By analysing the x-ray diffraction data of the latter specimen by using the single phase approach the results obtained was not according to experimental finding. Introducing two phase models for the `double-phase' 500-1200 mixture to accommodate the bimodal-size-distribution characteristics give Dv = 34(2) and σ = 0.10 for the `nanometric phase' and Dv = 363(0) and σ = 1.38 for the `sub-nanometric phase'.

  10. X-ray diffraction analysis of residual stress in zirconia dental composites

    NASA Astrophysics Data System (ADS)

    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.

  11. Laboratory manual: mineral X-ray diffraction data retrieval/plot computer program

    USGS Publications Warehouse

    Hauff, Phoebe L.; VanTrump, George

    1976-01-01

    The Mineral X-Ray Diffraction Data Retrieval/Plot Computer Program--XRDPLT (VanTrump and Hauff, 1976a) is used to retrieve and plot mineral X-ray diffraction data. The program operates on a file of mineral powder diffraction data (VanTrump and Hauff, 1976b) which contains two-theta or 'd' values, and intensities, chemical formula, mineral name, identification number, and mineral group code. XRDPLT is a machine-independent Fortran program which operates in time-sharing mode on a DEC System i0 computer and the Gerber plotter (Evenden, 1974). The program prompts the user to respond from a time-sharing terminal in a conversational format with the required input information. The program offers two major options: retrieval only; retrieval and plot. The first option retrieves mineral names, formulas, and groups from the file by identification number, by the mineral group code (a classification by chemistry or structure), or by searches based on the formula components. For example, it enables the user to search for minerals by major groups (i.e., feldspars, micas, amphiboles, oxides, phosphates, carbonates) by elemental composition (i.e., Fe, Cu, AI, Zn), or by a combination of these (i.e., all copper-bearing arsenates). The second option retrieves as the first, but also plots the retrieved 2-theta and intensity values as diagrammatic X-ray powder patterns on mylar sheets or overlays. These plots can be made using scale combinations compatible with chart recorder diffractograms and 114.59 mm powder camera films. The overlays are then used to separate or sieve out unrelated minerals until unknowns are matched and identified.

  12. Data preparation and evaluation techniques for x-ray diffraction microscopy

    DOE PAGESBeta

    Steinbrener, Jan; Nelson, Johanna; Huang, Xiaojing; Marchesini, Stefano; Shapiro, David; Turner, Joshua J.; Jacobsen, Chris

    2010-01-01

    The post-experiment processing of X-ray Diffraction Microscopy data is often time-consuming and difficult. This is mostly due to the fact that even if a preliminary result has been reconstructed, there is no definitive answer as to whether or not a better result with more consistently retrieved phases can still be obtained. In addition, we show here that the first step in data analysis, the assembly of two-dimensional diffraction patterns from a large set of raw diffraction data, is crucial to obtaining reconstructions of highest possible consistency. We have developed software that automates this process and results in consistently accurate diffractionmore » patterns. We have furthermore derived some criteria of validity for a tool commonly used to assess the consistency of reconstructions, the phase retrieval transfer function, and suggest a modified version that has improved utility for judging reconstruction quality.« less

  13. Performance characteristics needed for protein crystal diffraction x-ray detectors.

    SciTech Connect

    Westbrook, E. M.

    1999-09-21

    During the 1990's, macromolecular crystallography became progressively more dependent on synchrotrons X-ray sources for diffraction data collection. Detectors of this diffraction data at synchrotrons beamlines have evolved over the decade, from film to image phosphor plates, and then to CCD systems. These changes have been driven by the data quality and quantity improvements each newer detector technology provided. The improvements have been significant. It is likely that newer detector technologies will be adopted at synchrotron beamlines for crystallographic diffraction data collection in the future, but these technologies will have to compete with existing CCD detector systems which are already excellent and are getting incrementally better in terms of size, speed, efficiency, and resolving power. Detector development for this application at synchrotrons must concentrate on making systems which are bigger and faster than CCDs and which can capture weak data more efficiently. And there is a need for excellent detectors which are less expensive than CCD systems.

  14. Energy dispersive x-ray diffraction of charge density waves via chemical filtering

    SciTech Connect

    Feng Yejun; Somayazulu, M. S.; Jaramillo, R.; Rosenbaum, T.F.; Isaacs, E.D.; Hu Jingzhu; Mao Hokwang

    2005-06-15

    Pressure tuning of phase transitions is a powerful tool in condensed matter physics, permitting high-resolution studies while preserving fundamental symmetries. At the highest pressures, energy dispersive x-ray diffraction (EDXD) has been a critical method for geometrically confined diamond anvil cell experiments. We develop a chemical filter technique complementary to EDXD that permits the study of satellite peaks as weak as 10{sup -4} of the crystal Bragg diffraction. In particular, we map out the temperature dependence of the incommensurate charge density wave diffraction from single-crystal, elemental chromium. This technique provides the potential for future GPa pressure studies of many-body effects in a broad range of solid state systems.

  15. Spectral X-Ray Diffraction using a 6 Megapixel Photon Counting Array Detector

    PubMed Central

    Muir, Ryan D.; Pogranichniy, Nicholas R.; Muir, J. Lewis; Sullivan, Shane Z.; Battaile, Kevin P.; Mulichak, Anne M.; Toth, Scott J.; Keefe, Lisa J.; Simpson, Garth J.

    2016-01-01

    Pixel-array array detectors allow single-photon counting to be performed on a massively parallel scale, with several million counting circuits and detectors in the array. Because the number of photoelectrons produced at the detector surface depends on the photon energy, these detectors offer the possibility of spectral imaging. In this work, a statistical model of the instrument response is used to calibrate the detector on a per-pixel basis. In turn, the calibrated sensor was used to perform separation of dual-energy diffraction measurements into two monochromatic images. Targeting applications include multi-wavelength diffraction to aid in protein structure determination and X-ray diffraction imaging. PMID:27041789

  16. High resolution x-ray diffraction analysis of InGaAs/InP superlattices

    SciTech Connect

    Cornet, D. M.; LaPierre, R. R.; Comedi, D.; Pusep, Y. A.

    2006-08-15

    The interfacial properties of lattice-matched InGaAs/InP superlattice (SL) structures grown by gas source molecular beam epitaxy were investigated by high resolution x-ray diffraction (HRXRD). SLs with various periods were grown to determine the contributions of the interface layers to the structural properties of the SLs. The HRXRD curves exhibited a number of features indicative of interfacial layers, including weak even-order satellite peaks, and a zero-order diffraction peak that shifted toward lower diffraction angles with decreasing SL period. A detailed structural model is proposed to explain these observations, consisting of strained InAsP and InGaAsP monolayers due to the group-V gas switching and atomic exchange at the SL interfaces.

  17. A method of rapidly obtaining concentration-depth profiles from X-ray diffraction

    NASA Technical Reports Server (NTRS)

    Wiedemann, K. E.; Unnam, J.

    1985-01-01

    A broadened diffraction peak, or intensity band, is observed in the case diffraction from a nonhomogeneous phase in which the variations in compositions result in a range of lattice spacings. An intriguing aspect regarding the relationship between the X-ray diffraction band and the composition-depth profile is the hypersensitivity of the intensity band to the shape of the profile. A number of investigators have sought to use this sensitivity to construct high-precision profiles. Difficulties encountered are related to complications due to intensity broadening, and prohibitive computational requirements. Simulation techniques have provided the most accurate interpretation of the intensity band. However, the involved calculations have been prohibitively long. The present study discusses a technique which has simple computational requirements and is as accurate and flexible as the simulation techniques.

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

    PubMed Central

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

    2010-01-01

    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 R merge 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. PMID:21139221

  19. Estimating nanoscale deformation in bone by X-ray diffraction imaging method.

    PubMed

    Tadano, Shigeru; Giri, Bijay; Sato, Takuya; Fujisaki, Kazuhiro; Todoh, Masahiro

    2008-01-01

    Knowledge of internal stress-strain in bone tissue is important for clinical diagnosis and remedies. The inorganic mineral phase of apatite crystals in bone composite, because of its crystalline nature, provides a reliable way of measurement through X-ray diffraction system. Use of two-dimensional detector, imaging plate (IP), is considered to expedite the process with much more information, hence, is widely applied in the study of organization, stress, strain, etc. for crystalline substance. The distortion of Debye rings in the image obtained by IP can be directly related to the deformation in lattice plane of the crystals. Since X-ray diffraction method involves measurement at nano-level, proper focus on the extraction of data and corresponding analysis is needed. In the current work, we considered weighted average value of intensity to locate radius vectors along azimuthal direction in the diffracted rings from the primary array of digital data in steps of pixels. The widely applied approaches for profile shift measurement--peak shift and full width at half maximum (FWHM) of a peak, and shift of center of gravity of profile--were compared with a new concept of segmental shift (SS) proposed previously by the authors. We observed reliable and effective outcomes with higher precision in the consideration of SS while using IP as a detector. Our approach in this work for intensity integration and radius vector positioning especially add precision in such applications. PMID:18291405

  20. Effect of grain size on stability of X-ray diffraction patterns used for threat detection

    NASA Astrophysics Data System (ADS)

    Ghammraoui, B.; Rebuffel, V.; Tabary, J.; Paulus, C.; Verger, L.; Duvauchelle, Ph.

    2012-08-01

    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.