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Sample records for 3d x-ray diffraction

  1. A method based on diffraction theory for predicting 3D focusing performance of compound refractive X-ray lenses

    Zichun Le; Kai Liu; Jingqiu Liang

    2005-01-01

    A method based on the diffraction theory for estimating the three-dimensional (3D) focusing performance of the compound refractive X-ray lenses is presented in this paper. As a special application, the 3D X-ray intensity distribution near the focus is derived for a plano-concave compound refractive X-ray lens.Moreover, the computer codes are developed and some results of 3D focusing performance for a compound refractive X-ray lens with Si material are shown and discussed.

  2. New opportunities for 3D materials science of polycrystalline materials at the micrometre lengthscale by combined use of X-ray diffraction and X-ray imaging

    Ludwig, W.; King, A.; Reischig, P.;

    2009-01-01

    Non-destructive, three-dimensional (3D) characterization of the grain structure in mono-phase polycrystalline materials is an open challenge in material science. Recent advances in synchrotron based X-ray imaging and diffraction techniques offer interesting possibilities for mapping 3D grain shapes...... and crystallographic orientations for certain categories of polycrystalline materials. Direct visualisation of the three-dimensional grain boundary network or of two-phase (duplex) grain structures by means of absorption and/or phase contrast techniques may be possible, but is restricted to specific...... material systems. A recent extension of this methodology, termed X-ray diffraction contrast tomography (DCT), combines the principles of X-ray diffraction imaging, three-dimensional X-ray diffraction microscopy (3DXRD) and image reconstruction from projections. DCT provides simultaneous access to 3D grain...

  3. New opportunities for 3D materials science of polycrystalline materials at the micrometre lengthscale by combined use of X-ray diffraction and X-ray imaging

    Non-destructive, three-dimensional (3D) characterization of the grain structure in mono-phase polycrystalline materials is an open challenge in material science. Recent advances in synchrotron based X-ray imaging and diffraction techniques offer interesting possibilities for mapping 3D grain shapes and crystallographic orientations for certain categories of polycrystalline materials. Direct visualisation of the three-dimensional grain boundary network or of two-phase (duplex) grain structures by means of absorption and/or phase contrast techniques may be possible, but is restricted to specific material systems. A recent extension of this methodology, termed X-ray diffraction contrast tomography (DCT), combines the principles of X-ray diffraction imaging, three-dimensional X-ray diffraction microscopy (3DXRD) and image reconstruction from projections. DCT provides simultaneous access to 3D grain shape, crystallographic orientation and local attenuation coefficient distribution. The technique applies to the larger range of plastically undeformed, polycrystalline mono-phase materials, provided some conditions on grain size and texture are fulfilled. The straightforward combination with high-resolution microtomography opens interesting new possibilities for the observation of microstructure related damage and deformation mechanisms in these materials.

  4. New insights into single-grain mechanical behavior from temperature-dependent 3-D coherent X-ray diffraction

    Coherent X-ray diffraction is able to yield non-destructively 3-D strain maps with unprecedented resolution in small isolated crystals. In this work we have used this technique to investigate the mechanical behavior of a single grain within a Au polycrystalline film. The 111 Bragg reflection from a 1250×950×475 nm single grain has been successfully measured in three dimensions during thermomechanical loading. From these 3-D reciprocal space maps the displacement field is obtained through a specific phase-retrieval procedure. The uz(x,y,z) component of the displacement field component is deduced as a function of temperature with a high spatial resolution of 17×17×22 nm within the single grain. This displacement field is discussed with respect to grain-to-grain interactions in the supported metal film. This study opens important perspectives for the evaluation of mechanical properties of polycrystals via coherent X-ray diffraction

  5. X-Ray Diffraction.

    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)

  6. Characterization of 3D Trench PZT Capacitors for High Density FRAM Devices by Synchrotron X-ray Micro-diffraction

    Shin, Sangmin; Han, Hee; Park, Yong Jun; Choi, Jae-Young; Park, Youngsoo; Baik, Sunggi

    2007-01-01

    3D trench PbZrxTi1-xO3 (PZT) capacitors for 256 Mbit 1T-1C FRAM devices were characterized by synchrotron X-ray micro-diffraction at Pohang Light Source. Three layes, Ir/PZT/Ir were deposited on SiO2 trench holes with different widths ranging from 180 nm to 810 nm and 400 nm in depth by ALD and MOCVD. Each hole is separated from neighboring holes by 200 nm. The cross sectional TEM analysis for the trenches revealed that the PZT layers were consisted of columnar grains at the trench entrance and changes to polycrystalline granular grains at the lower part of the trench. The transition from columnar to granular grains was dependent on the trench size. The smaller trenches were favorable to granular grain formation. High resolution synchrotron X-ray diffraction analysis was performed to determine the crystal structure of each region. The beam was focused to about 500 μm and the diffraction patterns were obtained from a single trench. Only the peaks corresponding to ferroelectric tetragonal phases are observed for the trenches larger than 670 nm, which consist of fully columnar grains. However, the trenches smaller than 670 nm showed the peaks corresponding the pyrochlore phases, which suggested that the granular grains are of pyrochlore phases and non-ferroelectric.

  7. Characterization of 3D Trench PZT Capacitors for High Density FRAM Devices by Synchrotron X-ray Micro-diffraction

    3D trench PbZrxTi1-xO3 (PZT) capacitors for 256 Mbit 1T-1C FRAM devices were characterized by synchrotron X-ray micro-diffraction at Pohang Light Source. Three layers, Ir/PZT/Ir were deposited on SiO2 trench holes with different widths ranging from 180 nm to 810 nm and 400 nm in depth by ALD and MOCVD. Each hole is separated from neighboring holes by 200 nm. The cross sectional TEM analysis for the trenches revealed that the PZT layers were consisted of columnar grains at the trench entrance and changes to polycrystalline granular grains at the lower part of the trench. The transition from columnar to granular grains was dependent on the trench size. The smaller trenches were favorable to granular grain formation. High resolution synchrotron X-ray diffraction analysis was performed to determine the crystal structure of each region. The beam was focused to about 500 μm and the diffraction patterns were obtained from a single trench. Only the peaks corresponding to ferroelectric tetragonal phases are observed for the trenches larger than 670 nm, which consist of fully columnar grains. However, the trenches smaller than 670 nm showed the peaks corresponding the pyrochlore phases, which suggested that the granular grains are of pyrochlore phases and non-ferroelectric

  8. Stability of dislocation structures in copper towards stress relaxation investigated by high angular resolution 3D X-ray diffraction

    Jakobsen, Bo; Poulsen, Henning Friis; Lienert, Ulrich;

    2009-01-01

    A 300 µm thick tensile specimen of OFHC copper is subjected to a tensile loading sequence and deformed to a maximal strain of 3.11%. Using the novel three-dimensional X-ray diffraction method High angular resolution 3DXRD', the evolution of the microstructure within a deeply embedded grain is cha...

  9. X-ray diffraction

    We have been interested in structural elucidation by x-ray diffraction of compounds of biological interest. Understanding exactly how atoms are arranged in three-dimensional arrays as molecules can help explain the relationship between structure and functions. The species investigated may vary in size and shape; our recent studies included such diverse substances as antischistosomal drugs, a complex of cadmium with nucleic acid base, nitrate salts of adenine, and proteins

  10. X-ray diffraction

    The seventh edition of Philips' Review of literature on X-ray diffraction begins with a list of conference proceedings on the subject, organised by the Philips' organisation at regular intervals in various European countries. This is followed by a list of bulletins. The bibliography is divided according to the equipment (cameras, diffractometers, monochromators) and its applications. The applications are subdivided into sections for high/low temperature and pressure, effects due to the equipment, small angle scattering and a part for stress, texture and phase analyses of metals and quantitative analysis of minerals

  11. Interface Orientation Distribution during Grain Growth in Bulk SrTiO3 Measured by Means of 3D X-Ray Diffraction Contrast Tomography

    Syha, Melanie; Rheinheimer, Wolfgang; Bäurer, Michael;

    2012-01-01

    interface normal distribution clearly shows a preference for (100) oriented interfaces in the selected grains when annealed at 1600°C. This observation can be connected to existent interfacial energy estimations resulting from capillarity vector reconstructions. © 2012 Materials Research Society.......3D x-ray diffraction contrast tomography (DCT) is a non-destructive technique for the determination of grain shape and crystallography in polycrystalline bulk materials. Using this technique, a strontium titanate specimen was repeatedly measured between annealing steps.. A systematic analysis of...

  12. X-ray diffraction apparatus

    The invention provides an x-ray diffraction apparatus permitting the rotation of the divergence sit in conjunction with the rotation of the x-ray irradiated specimen, whereby the dimensions of the x-ray irradiated portion of the specimen remain substantially constant during the rotation of the specimen. In a preferred embodiment, the divergence slit is connected to a structural element linked with a second structural element connected to the specimen such that the divergence slit rotates at a lower angular speed than the specimen

  13. 3-D growth of a short fatigue crack within a polycrystalline microstructure studied using combined diffraction and phase-contrast X-ray tomography

    Herbig, M.; King, Andrew; Reischig, Peter;

    2011-01-01

    X-ray diffraction contrast tomography is a recently developed, non-destructive synchrotron imaging technique which characterizes microstructure and grain orientation in polycrystalline materials in three dimensions. By combining it with propagation-based phase-contrast tomography it is possible t...... beta titanium alloy Ti 21S that allows for visualization and analysis of the growth rate and crystallographic orientation of the fracture surface....

  14. Submicron X-ray diffraction

    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 beam line has a unity magnification toroidal mirror that produces a 50 by 200 micron focus just inside an x-ray hutch at the position of an x-y slit. The beam path in the hutch consists of source defining slits, a four bounce Ge or Si monochromator, followed by elliptically bent Kirkpatrick-Baez mirror pair which focuses the beam from the slits to sub micron dimensions (0.8 x 0.8 microns). An important feature of this arrangement is the ability to switch between white and monochromatic beams that are essential for characterizing crystals or crystal grains in the sub-micron range. Since sample rotation is fixed they have facilities for precision translation of the specimen to allow them to scan different crystal regions or grains. The sample stage rests on a state of the art six-circle diffractometer equipped with encoders in the main rotation stages calibrated to a second of arc. The detector is a 4K x 4K CCD (Bruker) with a 9 x 9 cm view area mounted on a detector arm that can be positioned around the sample. The detector itself can also be positioned to better than 1 micron along the detector arm. Using this facility they have been able to measure the orientation structure of single grains of passivated or buried Al interconnect test structures. Such structures or their equivalents are important in connecting individual components on integrated circuits. Their sub-micron dimensions result in very high current densities that can result in interconnect failures. The variation in sub-grain structure in a single grain is rich in detail. They have obtained detailed maps of misorientations in single grains using white beam Laue diffraction patterns From these they have been

  15. X-ray topography and multiple diffraction

    A short summary on X-ray topography, which is based on the dynamical theory of X-ray diffraction, is made. The applications and properties related to the use of the multiple diffraction technique are analized and discussed. (L.C.)

  16. X-Ray Diffractive Optics

    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. Two-dimensional x-ray diffraction

    He, Bob B

    2009-01-01

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

  18. X-ray diffraction imaging and analysis

    The first papers dealing with the very important application of x-ray diffraction to crystal structure analysis were also published in 1912 by W.L. Bragg, while a student at Cambridge. Bragg performed an analysis of the Laue diffraction pattern of zinc blend and determined the correct structure of the crystal lattice. There have been many practical applications for x-ray diffraction techniques. Historically conventional x-ray machines were used as generators and film used as the recording medium. Prior to 1966, all attempts to directly image x-ray diffraction patterns used a large format x-ray image intensifier tube of the same type as conventionally used for medical and industrial fluoroscopy. Since the 1960's numerous electro-optical systems have been developed which are far better suited for real-time viewing and recording of x-ray diffraction patterns. Modern x-ray diffraction imaging systems incorporating rotating anode and pulsed x-ray generators, synchrotron x-ray sources, and optimized electro-optical systems have been used to orient single crystals, to study crystal lattice rotation accompanying plastic deformation, to measure the rate of grain boundary migration during recrystallization annealing of cold-worked metals, to determine the physical state of exploding metals, to rapidly measure residual stress (strain), to study the dynamics of structural phase transitions in ferroelectric crystals, to monitor the amorphous to crystalline phase transformation of rapidly solidified metals, and to record topographic images of lattice defects in quartz, gallium arsenide and nickel alloy turbine blade crystals

  19. 3D Rotational X-Ray guidance for surgical interventions

    Kraats, Everine Brenda van de

    2005-01-01

    The research described in this thesis is aimed at increasing the accuracy and decreasing the invasiveness of surgical procedures, with a focus on spine procedures, by using a combination of multi-modality images, computer-assisted navigation, intraoperative 3D rotational X-ray (3DRX) imaging, and mi

  20. Diffraction enhanced x-ray imaging

    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

  1. Soft x-ray resonant magnetic diffraction.

    Wilkins, S. B.; Hatton, P. D.; Roper, M.D.; Prabhakaran, D.; Boothroyd, A. T.

    2003-01-01

    We have conducted the first soft x-ray diffraction experiments from a bulk single crystal, studying the bilayer manganite La22xSr12xMn2O7 with x 0:475 in which we were able to access the (002) Bragg reflection using soft x rays. The Bragg reflection displays a strong resonant enhancement at the LIII and LII manganese absorption edges. We demonstrate that the resonant enhancement of the magnetic diffraction of the (001) is extremely large, indeed so large that it exceeds that of t...

  2. Single Particle X-ray Diffractive Imaging

    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.

  3. The Dynamical Theory of X Ray Diffraction

    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)

  4. Advanced X-ray diffractive optics

    Vila-Comamala, J; Jefimovs, K; Sarkar, S S; Solak, H H; Guzenko, V A; Stampanoni, M; Marone, F; Raabe, J; Tzvetkov, G; Grolimund, D; Borca, C N; David, C [Paul Scherrer Institut, CH-5232 Villigen PSI (Switzerland); Pilvi, T; Ritala, M [Department of Chemistry, FIN-00014 University of Helsinki (Finland); Fink, R H [Friedrich-Alexander Universitaet, D-91058 Erlangen (Germany); Kaulich, B, E-mail: joan.vila@psi.c [ELETTRA Sincrotrone, I-34012 Basovizza (Italy)

    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.

  5. X-ray energy dispersive diffraction

    X-ray energy dispersive diffraction is used mainly for structural characterization of polycrystalline powders and amorphous materials. One of the important features of it is the fixed scattering angle facilitating in particular studies of materials in special environments (e.g., high pressure, high and low temperature). There are two versions of X-ray energy dispersive diffraction. In one - called XED - an incident 'white' beam is used and the spectral distribution of the diffracted photons is analyzed by means of a solid state detector. Its important feature is the simultaneous appearance of all reflections. In the other version - called monochromator scan method (MSM) - the incident beam is monochromatic and its wavelength is changed stepwise by rotating the crystal monochromator. (orig.)

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

    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.

  7. Basic of X-ray diffraction

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

    1996-09-01

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

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

    2012-01-01

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

  9. 3D synchrotron x-ray microtomography of paint samples

    Ferreira, Ester S. B.; Boon, Jaap J.; van der Horst, Jerre; Scherrer, Nadim C.; Marone, Federica; Stampanoni, Marco

    2009-07-01

    Synchrotron based X-ray microtomography is a novel way to examine paint samples. The three dimensional distribution of pigment particles, binding media and their deterioration products as well as other features such as voids, are made visible in their original context through a computing environment without the need of physical sectioning. This avoids manipulation related artefacts. Experiments on paint chips (approximately 500 micron wide) were done on the TOMCAT beam line (TOmographic Microscopy and Coherent rAdiology experimenTs) at the Paul Scherrer Institute in Villigen, CH, using an x-ray energy of up to 40 keV. The x-ray absorption images are obtained at a resolution of 350 nm. The 3D dataset was analysed using the commercial 3D imaging software Avizo 5.1. Through this process, virtual sections of the paint sample can be obtained in any orientation. One of the topics currently under research are the ground layers of paintings by Cuno Amiet (1868- 1961), one of the most important Swiss painters of classical modernism, whose early work is currently the focus of research at the Swiss Institute for Art Research (SIK-ISEA). This technique gives access to information such as sample surface morphology, porosity, particle size distribution and even particle identification. In the case of calcium carbonate grounds for example, features like microfossils present in natural chalks, can be reconstructed and their species identified, thus potentially providing information towards the mineral origin. One further elegant feature of this technique is that a target section can be selected within the 3D data set, before exposing it to obtain chemical data. Virtual sections can then be compared with cross sections of the same samples made in the traditional way.

  10. Glancing angle synchrotron X-ray diffraction

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

  11. Glancing angle synchrotron X-ray diffraction

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

    1996-09-01

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

  12. X-Ray Diffraction on NIF

    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.

  13. 3D -Ray Diffraction Microscopy

    Poulsen, Henning Friis; Schmidt, Søren; Juul Jensen, Dorte;

    2014-01-01

    Three-dimensional X-ray diffraction (3DXRD) microscopy is a fast and non-destructive structural characterization technique aimed at the study of individual crystalline elements (grains or subgrains) within mm-sized polycrystalline specimens. It is based on two principles: the use of highly penetr...

  14. Microstresses and x-ray diffraction

    Drahokoupil, J.; Čerňanský, Marian; Ganev, N.; Kolařík, K.; Pala, Z.

    Ostrava: VŠB - TU, 2008 - (Fuxa, J.; Macura, F.; Halama, R.), s. 94-98 ISBN 978-80-248-1774-3. [Experimental Stress Analysis 2008 /46./. Horní Bečva (CZ), 02.06.2008-05.06.2008] R&D Projects: GA ČR GA106/07/0805 Institutional research plan: CEZ:AV0Z10100520 Keywords : microstress and macrostress * shot peening * x-ray diffraction * depth distribution Subject RIV: BM - Solid Matter Physics ; Magnetism

  15. Study of 3-D stress development in parent and twin pairs of a hexagonal close-packed polycrystal: Part I – in-situ three-dimensional synchrotron X-ray diffraction measurement

    High anisotropy in the elastic and plastic properties of hexagonal close-packed (hcp) structured metals not only results in drastic stress variation across grain boundaries, but also heterogeneous distributions within grains. Understanding the mechanism of load sharing between different grains becomes more complicated when deformation twinning plays a significant role in accommodating an externally applied load. In this paper, a comprehensive study of stress development in a coarse grained strongly textured hcp polycrystal Zircaloy-2, is given using three-dimensional X-ray diffraction (3DXRD) microscopy. In-situ uniaxial straining was carried out at seven steps up to 2.7% in the macroscopic direction that favors twin formation, while center-of-mass position, crystallographic orientation, elastic strain, stress, and relative volume of each grain were measured. This information was used to reconstruct the 3D microstructure and statistically study neighborhood effects on the load sharing. The investigated volume of the sample contained 6132 grains initially, yet as a result of twin formation, 9724 grains were measured in the same volume at the last loading step. It is shown that the most favored (highest Schmid factor) twin variant contributes the most to the twin number fraction; however, if the measured local stress within each grain is used for the calculation of Schmid factor, the contribution of other variants is relatively independent of Schmid factor

  16. Towards magnetic 3D x-ray imaging

    Fischer, Peter; Streubel, R.; Im, M.-Y.; Parkinson, D.; Hong, J.-I.; Schmidt, O. G.; Makarov, D.

    2014-03-01

    Mesoscale phenomena in magnetism will add essential parameters to improve speed, size and energy efficiency of spin driven devices. Multidimensional visualization techniques will be crucial to achieve mesoscience goals. Magnetic tomography is of large interest to understand e.g. interfaces in magnetic multilayers, the inner structure of magnetic nanocrystals, nanowires or the functionality of artificial 3D magnetic nanostructures. We have developed tomographic capabilities with magnetic full-field soft X-ray microscopy combining X-MCD as element specific magnetic contrast mechanism, high spatial and temporal resolution due to the Fresnel zone plate optics. At beamline 6.1.2 at the ALS (Berkeley CA) a new rotation stage allows recording an angular series (up to 360 deg) of high precision 2D projection images. Applying state-of-the-art reconstruction algorithms it is possible to retrieve the full 3D structure. We will present results on prototypic rolled-up Ni and Co/Pt tubes and glass capillaries coated with magnetic films and compare to other 3D imaging approaches e.g. in electron microscopy. Supported by BES MSD DOE Contract No. DE-AC02-05-CH11231 and ERC under the EU FP7 program (grant agreement No. 306277).

  17. X-ray tomography: Biological cells in 3-D at better than 50 nm resolution

    Full text: X-ray microscopy can be used to image whole, hydrated, specimens with a spatial resolution 5-10 times better than that obtained using visible light microscopy. X-ray imaging at photon energies below the K- absorption edge of oxygen, referred to as the water window, exploits the strong natural contrast for organic material embedded in a mostly water matrix. With a transmission X-ray microscope using Fresnel zone plate optics, specimens up to 10 microns thick can be examined. The highest X-ray transmission in hydrated samples is obtained at a wavelength of 2.4 nm but, due to the low numerical aperture of zone plate lenses operated in st order diffraction mode the structures resolved are much larger than the X-ray wavelength. Because of the low NA of X-ray lenses (NA=0.05), combined with the effect of polychromatic illumination and a wavelength dependant focal length, the effective depth of ld is large (6-10 microns). The experiments presented here were performed at the Advanced Light Source using the full ld transmission X-ray microscope, XM-1. This microscope employs a bend magnet X-ray source and zone plate condenser and objective lenses. The condenser zone plate acts as a monochromator and the X-ray images are recorded directly on a cooled, back-thinned 1024x1024 pixel CCD camera. The sample holder was a rotationally symmetric glass tube; the region containing the sample was 10 microns in diameter with a wall thickness of 200 nm. Live yeast cells were loaded into the tube, rapidly frozen by a blast of liquid nitrogen-cooled helium gas, and maintained at 140 deg C by a steady flow of cold helium. The image sequence spanned 180 deg and consisted of 45 images spaced by 4 deg. The images were aligned to a common axis and computed tomographic reconstruction was used to obtain the 3-D X-ray linear absorption coefficient. Volume rendering and animation of reconstructed data was performed using the 3-D program, Amira. Acquisition time for 90 images was 3 min

  18. X-ray imaging of laser produced plasmas by a compound 3D x-ray lens

    Pilot scheme for the study of plasma under extreme condition is implemented using a compound 3D X-ray lens. Hard X-ray image of laser plasma produced by irradiating of copper foil by intense laser pulse was recorded using this lens

  19. X-ray high-resolution diffraction using refractive lenses

    Drakopoulos, Michael; Snigirev, Anatoly; Snigireva, Irina; Schilling, Jörg

    2005-01-01

    Refractive x-ray lenses have recently been applied for imaging and scanning microscopy with hard x rays. We report the application of refractive lenses in an optical scheme for high-resolution x-ray diffraction, performed at a high brilliance synchrotron radiation source. An experimental proof of principle and a theoretical discussion are presented. In particular, we observe the x-ray diffraction pattern from a two-dimensional photonic crystal with 4.2 µm periodicity, which normally is employ...

  20. Application of the probability theory in predicting 3D focusing behaviors of compound X-ray refractive lenses

    Zichun Le; Xinjian Zhao; Jingqiu Liang; Yaping Sun; Kai Liu; Ming Zhang; Shuqin Guo; Bisheng Quan

    2005-01-01

    A theoretical method based on the diffractive theory is used for predicting three-dimensional (3D) focusing performances of the compound X-rays refractive lenses (CRLs). However, the derivation of the 3D intensity distribution near focus for the X-ray refractive lenses is quite complicated. In this paper, we introduce a simple theoretical method that is based on the first and second moments in the theory of probability. As an example, the 3D focusing performance of a CRL with Si material is predicted. Moreover, the results are compared with those obtained by the diffractive theory. It is shown that the method introduced in this paper is accurate enough.

  1. X-ray diffraction in phase characterisation

    Full text: The technique of X-ray diffraction (XRD) began in 1912 when von Laue discovered that crystalline materials interact with X-rays in a manner that reveals the underlying structure of the phase(s) present in the sample. Initially, the method was only used for the determination of crystal structure, but more recent developments have seen its application in a number of areas. 1) Phase identification; the positions of the lines in an XRD pattern are determined by the crystal symmetry, the unit cell dimensions and the wavelength used to collect the data while their intensities are proportional to the type and location of the atom within the unit cell. The arrangement of lines in a diffraction pattern serves as a 'finger-print' for the phase allowing it to be identified in pure or multi-phase samples. 2)Crystallite size and strain; decreasing crystallite size and increasing micro-strain both have the effect of increasing the observed peak widths in a diffraction pattern. However, since the effect of size and strain vary differently as function of diffraction angle (secθ and tanθ respectively), it is possible to determine the size and strain components using wide range diffraction data. 3)Crystal structure refinement; the advent of the Rietveld method in the late 1960's allowed the refinement of known (or partially known) crystal structures without the need to decompose the pattern into individual peak intensities. The method relies on (i) calculating a diffraction from a model which includes the crystal structure, pattern background and peak width and shape, (ii) comparing the calculated pattern with the observed data, and (iii) minimising the difference between the calculated and observed patterns by varying the model in a least-squares minimisation process. 4) Phase quantification; the strength of XRD lies in the fact that it is one of the few techniques that is sensitive to the phases present in the sample. Since an XRD pattern is produced by the crystal

  2. Oscillation photography applied to resonant x-ray diffraction

    Inami, T [Synchrotron Radiation Research Unit, Japan Atomic Energy Agency, Hyogo 679-5148 (Japan); Toyokawa, H [Japan Synchrotron Radiation Research Institute, Hyogo 679-5198 (Japan); Terada, N; Kitazawa, H, E-mail: inami@spring8.or.j [National Institute for Materials Science, Tsukuba 305-0047 (Japan)

    2009-03-01

    Recently, resonant x-ray diffraction has been used for detecting charge, magnetic and multipole orders. In practice, however, this technique surveys only a small portion of the reciprocal space. In this study, we applied oscillation photography to resonant x-ray diffraction. For a test sample, we explored nearly a whole Brillouin zone and successfully observed resonant peaks. This feasibility study indicates that oscillation photography is useful for expanding observable areas and enhances the capability of resonant x-ray diffraction.

  3. X-ray diffraction from shock-loaded polycrystals

    Swift, Damian C.

    2007-01-01

    X-ray diffraction was demonstrated from shock-compressed polycrystalline metal on nanosecond time scales. Laser ablation was used to induce shock waves in polycrystalline foils of Be, 25 to 125 microns thick. A second laser pulse was used to generate a plasma x-ray source by irradiation of a Ti foil. The x-ray source was collimated to produce a beam of controllable diameter, and the beam was directed at the Be sample. X-rays were diffracted from the sample, and detected using films and x-ray ...

  4. Advanced X-ray diffractive optics

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

    2009-01-01

    X-ray microscopy greatly bene�ts from the advances in x-ray optics. At the Paul Scherrer Institut, developments in x-ray di�ractive optics include the manufacture and optimization of Fresnel zone plates (FZPs) and di�ractive 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 p...

  5. Development of a 3-D x-ray system

    Evans, J P O

    1993-01-01

    major departure has been the introduction of a dual energy linear x-ray detector array which will allow, in general, the discrimination between organic and inorganic substances. The second design is a compromise between ease of visual inspection for human observers and optimum three-dimensional co-ordinate measurement capability. The system is part of an on going research programme into the possibility of introducing psychological depth cues into the resultant x-ray images. The research presented in this thesis was initiated to enhance the visual interpretation of complex x-ray images, specifically in response to problems encountered in the routine screening of freight by HM. Customs and Excise. This phase of the work culminated in the development of the first experimental machine. During this work the security industry was starting to adopt a new type of x-ray detector, namely the dual energy x-ray sensor. The Department of Transport made available funding to the Police Scientific Development Branch (P.S.D.B...

  6. Measuring the 3D shape of X-ray clusters

    Samsing, Johan; Hansen, Steen H

    2012-01-01

    Observations and numerical simulations of galaxy clusters strongly indicate that the hot intracluster x-ray emitting gas is not spherically symmetric. In many earlier studies spherical symmetry has been assumed partly because of limited data quality, however new deep observations and instrumental designs will make it possible to go beyond that assumption. Measuring the temperature and density profiles are of interest when observing the x-ray gas, however the spatial shape of the gas itself also carries very useful information. For example, it is believed that the x-ray gas shape in the inner parts of galaxy clusters is greatly affected by feedback mechanisms, cooling and rotation, and measuring this shape can therefore indirectly provide information on these mechanisms. In this paper we present a novel method to measure the three-dimensional shape of the intracluster x-ray emitting gas. We can measure the shape from the x-ray observations only, i.e. the method does not require combination with independent mea...

  7. Mammography spectrum measurement using an x-ray diffraction device

    The use of a diffraction spectrometer developed by Deslattes for the determination of mammographic kV is extended to the measurement of accurate, relative x-ray spectra. Raw x-ray spectra (photon fluence versus energy) are determined by passing an x-ray beam through a bent quartz diffraction crystal, and the diffracted x-rays are detected by an x-ray intensifying screen coupled to a charge coupled device. Two nonlinear correction procedures, one operating on the energy axis and the other operating on the fluence axis, are described and performed on measured x-ray spectra. The corrected x-ray spectra are compared against tabulated x-ray spectra measured under nearly identical conditions. Results indicate that the current device is capable of producing accurate relative x-ray spectral measurements in the energy region from 12 keV to 40 keV, which represents most of the screen-film mammography energy range. Twelve keV is the low-energy cut-off, due to the design geometry of the device. The spectrometer was also used to determine the energy-dependent x-ray mass attenuation coefficients for aluminium, with excellent results in the 12-30 keV range. Additional utility of the device for accurately determining the attenuation characteristics of various normal and abnormal breast tissues and phantom substitutes is anticipated. (author)

  8. Energy-dispersive X-ray diffraction mapping on a benchtop X-ray fluorescence system

    Lane, DW; Nyombi, A; Shackel, J

    2014-01-01

    A method for energy-dispersive X-ray diffraction mapping is presented, using a conventional low-power benchtop X-ray fluorescence spectrometer, the Seiko Instruments SEA6000VX. Hyper spectral X-ray maps with a 10µm step size were collected from polished metal surfaces, sectioned Bi, Pb and steel shot gun pellets. Candidate diffraction lines were identified by eliminating those that matched a characteristic line for an element and those predicted for escape peaks, sum peaks, and Rayleigh and C...

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

    The Fifth School on X-ray diffraction from polycrystalline materials was devoted to thin film characterization by advanced X-ray diffraction techniques. Twenty contributions are contained in this volume; all twenty are recorded in the INIS Database. X-ray diffraction is known to be a powerful analytical tool for characterizing materials and understanding their structural features. The aim of these articles is to illustrate the fundamental contribution of modern diffraction techniques (grazing incidence, surface analysis, standing waves, etc.) to the characterization of thin and ultra-thin films, which have become important in many advanced technologies

  10. Femtosecond x-ray diffraction: experiments and limits

    Wark, Justin S.; Allen, A. M.; Ansbro, P. C.; Bucksbaum, Philip H.; Chang, Zenghu; DeCamp, Mark F.; Falcone, Roger W.; Heimann, Philip A.; Johnson, S. L.; Kang, Inuk; Kapteyn, Henry C.; Larsson, Jorgen; Lee, Richard W.; Lindenberg, Aaron; Merlin, Roberto D.; Missalla, Thomas; Naylor, G.; Padmore, Howard A.; Reis, David A.; Scheidt, K.; Sjoegren, Anders; Sondhauss, P. C.; Wulff, Michael

    2001-01-01

    Although the realisation of femtosecond X-ray free electron laser (FEL) X-ray pulses is still some time away, X-ray diffraction experiments within the sub-picosecond domain are already being performed using both synchrotron and laser- plasma based X-ray sources. Within this paper we summarise the current status of some of these experiments which, to date, have mainly concentrated on observing non-thermal melt and coherent phonons in laser-irradiated semiconductors. Furthermore, with the advent of FEL sources, X-ray pulse lengths may soon be sufficiently short that the finite response time of monochromators may themselves place fundamental limits on achievable temporal resolution. A brief review of time-dependent X-ray diffraction relevant to such effects is presented.

  11. Magnetic X-ray diffraction from samarium

    Watson, D. [School of Physics and Space Research, University of Birmingham, Birmingham B15 2TT (United Kingdom); Forgan, E.M. [School of Physics and Space Research, University of Birmingham, Birmingham B15 2TT (United Kingdom); Stirling, W.G. [Department of Physics, University of Keele, Keele, Staffs ST5 5BG (United Kingdom); Nuttall, W.J. [Department of Physics, University of Keele, Keele, Staffs ST5 5BG (United Kingdom); Perry, S.C. [Department of Physics, University of Keele, Keele, Staffs ST5 5BG (United Kingdom); Costa, M.M.R. [Physics Department, Universidade de Coimbra, 3000 Coimbra (Portugal); Fort, D. [School of Metallurgy and Materials, University of Birmingham, Birmingham B15 2TT (United Kingdom)

    1995-02-09

    We report X-ray scattering observations on antiferromagnetic samarium, using the NSLS synchrotron source. We have made new observations of the absorption-corrected energy dependence and temperature variation of the resonantly enhanced magnetic signal from the hexagonal sites near the L{sub III} edge. ((orig.)).

  12. Amorphous silica studied by high energy x-ray diffraction

    Poulsen, H.F.; Neuefeind, J.; Neumann, H.B.;

    1995-01-01

    The use of hard X-rays (60-300 keV) for diffraction studies of disordered materials has several advantages: higher resolution in direct space, smaller correction terms, removal of truncation effects, the possibility for operating in extreme environments and for direct comparison between X-ray and...

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

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

    1988-01-01

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

  14. X-ray diffraction pattern and deformation texture of beeswax

    Schoening, F.R.L. (University of the Witwatersrand, Johannesburg (South Africa). Dept. of Physics)

    1980-06-01

    The x-ray diffraction pattern of beeswax shows paraffin-like spacings which have been attributed to monoesters, and long spacings which have been attributed to diesters and hydrocarbons. The d-values and line intensities are given. Optical and x-ray observations of deformed specimens indicate that the molecular axes tend to lie perpendicular to the direction of elongation.

  15. 2D and 3D Refraction Based X-ray Imaging Suitable for Clinical and Pathological Diagnosis

    Ando, Masami; Bando, Hiroko; Chen, Zhihua; Chikaura, Yoshinori; Choi, Chang-Hyuk; Endo, Tokiko; Esumi, Hiroyasu; Gang, Li; Hashimoto, Eiko; Hirano, Keiichi; Hyodo, Kazuyuki; Ichihara, Shu; Jheon, SangHoon; Kim, HongTae; Kim, JongKi; Kimura, Tatsuro; Lee, ChangHyun; Maksimenko, Anton; Ohbayashi, Chiho; Park, SungHwan; Shimao, Daisuke; Sugiyama, Hiroshi; Tang, Jintian; Ueno, Ei; Yamasaki, Katsuhito; Yuasa, Tetsuya

    2007-01-01

    The first observation of micro papillary (MP) breast cancer by x-ray dark-field imaging (XDFI) and the first observation of the 3D x-ray internal structure of another breast cancer, ductal carcinoma in-situ (DCIS), are reported. The specimen size for the sheet-shaped MP was 26 mm × 22 mm × 2.8 mm, and that for the rod-shaped DCIS was 3.6 mm in diameter and 4.7 mm in height. The experiment was performed at the Photon Factory, KEK: High Energy Accelerator Research Organization. We achieved a high-contrast x-ray image by adopting a thickness-controlled transmission-type angular analyzer that allows only refraction components from the object for 2D imaging. This provides a high-contrast image of cancer-cell nests, cancer cells and stroma. For x-ray 3D imaging, a new algorithm due to the refraction for x-ray CT was created. The angular information was acquired by x-ray optics diffraction-enhanced imaging (DEI). The number of data was 900 for each reconstruction. A reconstructed CT image may include ductus lactiferi, micro calcification and the breast gland. This modality has the possibility to open up a new clinical and pathological diagnosis using x-ray, offering more precise inspection and detection of early signs of breast cancer.

  16. 2D and 3D Refraction Based X-ray Imaging Suitable for Clinical and Pathological Diagnosis

    The first observation of micro papillary (MP) breast cancer by x-ray dark-field imaging (XDFI) and the first observation of the 3D x-ray internal structure of another breast cancer, ductal carcinoma in-situ (DCIS), are reported. The specimen size for the sheet-shaped MP was 26 mm x 22 mm x 2.8 mm, and that for the rod-shaped DCIS was 3.6 mm in diameter and 4.7 mm in height. The experiment was performed at the Photon Factory, KEK: High Energy Accelerator Research Organization. We achieved a high-contrast x-ray image by adopting a thickness-controlled transmission-type angular analyzer that allows only refraction components from the object for 2D imaging. This provides a high-contrast image of cancer-cell nests, cancer cells and stroma. For x-ray 3D imaging, a new algorithm due to the refraction for x-ray CT was created. The angular information was acquired by x-ray optics diffraction-enhanced imaging (DEI). The number of data was 900 for each reconstruction. A reconstructed CT image may include ductus lactiferi, micro calcification and the breast gland. This modality has the possibility to open up a new clinical and pathological diagnosis using x-ray, offering more precise inspection and detection of early signs of breast cancer

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

    Frankær, Christian Grundahl

    and R6) were solved by single crystal X-ray diffraction (XRD) to 1.40 Å, 1.30 Å and 1.80 Å resolution, respectively. The zinc coordination in each conformation was studied by XAS including both extended X-ray absorption fine structure (EXAFS) spectroscopy and X-ray absorption near edge structure...... the zinc coordination in the T3-sites, in particular. Furthermore, XANES spectra for the zinc sites in T6 and R6 insulin were successfully calculated using finite difference methods, and the bond distances and angles were optimized from a quantitative XANES analysis. T6 insulin was furthermore...

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

    Sutter, John P.

    2011-09-01

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

  19. X-ray diffraction radiation in conditions of Cherenkov effect

    Tishchenko, A. A.; Potylitsyn, A. P.; Strikhanov, M. N.

    2006-01-01

    X-ray diffraction radiation from ultra-relativistic electrons moving near an absorbing target is considered. The emission yield is found to increase significantly in conditions of Cherenkov effect. (c) 2006 Elsevier B.V. All rights reserved.

  20. Simulating X-ray diffraction of textured films

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

    2008-01-01

    Computationally efficient simulations of grazing-incidence X-ray diffraction (GIXD) are discussed, with particular attention given to textured thin polycrystalline films on supporting substrates. A computer program has been developed for simulating scattering from thin films exhibiting varying...

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

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

    1996-09-01

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

  2. 3D contrast-enhanced MR portography and direct X-ray portography: a correlation study

    Objective: To evaluate the accuracy of 3D contrast-enhanced MR portography (3D CEMRP) by correlating with direct X-ray portography. Methods: Twenty-six patients underwent 3D CEMRP study. The findings of 3D CEMRP including the patency of the portal vein and its intrahepatic left and right branches, as well as collaterals were evaluated and compared with those from direct x-ray portography. Causes of disagreement between the two methods were analyzed. Results: The main portal vein appearance was accordant with 3D CEMRP and direct x-ray portography in all cases. For intrahepatic portal veins, the results agreed in 21 patients but disagreed in 5. In one patient with a huge tumor in right liver, the right posterior portal vein was classified as occluded at 3D CEMRP, but displaced and diffusely narrowed at direct x-ray portography. The findings of left intrahepatic portal vein were discordant in three patients with hepatocelluar carcinoma in the left lobe. 3D CE MRP demonstrated complete occlusion of the left portal veins, whereas direct x-ray portography showed proximal narrowing and distal occlusion. In another patient with hepatocelluar carcinoma, a small non-occlusive thrombus involving the sagittal segment of the left portal vein was seen on MRP but not on direct x-ray portography. With demonstration of portosystemic collaterals, 3D CEMRP showed results similar to those of X-ray portography, except one recanalized para-umbilical vein was excluded from the limited scan coverage. Conclusion: 3D CE MRP correlated well with direct x-ray portography in most cases. Compared with direct portography, 3D CEMRP had limitation in distinguishing narrowing of an intrahepatic portal vein from occlusion. But it showed advantage in demonstrating small thrombus within portal vein. (authors)

  3. X-ray diffraction identification of clay minerals by microcomputer

    The identification of clay minerals by X-ray powder diffraction are done by searching an unknown pattern with a file of standard X-ray diffraction patterns. For this searching done by hand is necessary a long time. This paper shows a program in ''Basic'' language to be utilized in microcomputers for the math of the unknown pattern, using the high velocity of comparison of the microcomputer. A few minutes are used for the match. (author)

  4. DIFFRACTION LIMIT OF THE X-RAY REFRACTIVE LENSES

    Jaskevich, Y. R.; Kravchenko, O. I.; Chembrovsky, A. G.

    2013-01-01

    A compound X-ray lenses is an array of microlenses with a common axis. The resolution limited by aberration and by diffraction. Aberration can be corrected by shaping refractive surfaces for the experiment geometry. Due to the small value of refractive index the ideal shape of the surface is similar to the parabola. Diffraction limit comes from single slit theory based on absorption aperture of the compound refractive lenses. X-rays passing through lenses form Airy pattern. The size ...

  5. Synchrotron x-ray diffraction study of liquid surfaces

    Als-Nielsen, Jens Aage; Pershan, P.S.

    1983-01-01

    A spectrometer for X-ray diffraction and refraction studies of horizontal, free surfaces of liquids is described. As an illustration smetic-A layering at the surface of a liquid crystal is presented.......A spectrometer for X-ray diffraction and refraction studies of horizontal, free surfaces of liquids is described. As an illustration smetic-A layering at the surface of a liquid crystal is presented....

  6. X-ray diffraction microscopy based on refractive optics

    Roth, Thomas; Snigireva, Irina; Snigirev, Anatoly

    2014-01-01

    We describe a diffraction microscopy technique based on refractive optics to study structural variations in crystals. The X-ray beam diffracted by a crystal was magnified by beryllium parabolic refractive lenses on a 2D X-ray camera. The microscopy setup was integrated into the 6-circle Huber diffractometer at the ESRF beamline ID06. Our setup allowed to visualize structural imperfections with a resolution of approximately 1 micrometer. The configuration, however, can easily be adapted for sub-micrometer resolution.

  7. High energy X-ray diffraction

    from the sample within the angular acceptance given by the experimental setup. Due to the use of high energy x-rays bulk investigations of several mm thick Al plates are possible. The depth resolution is achieved by the use of a spiral slit. Simply spoken, it consists of twelve equidistant concentric spiral apertures cut into a WC plate. All paths through the 2 mm thick plate lie on cones, which have one common apex (i.e. the focal point of the slit system; here 50 mm). The azimuth selective depth resolved signal is recorded with an online image plate scanner. The technique permitted to map for the first time, non-destructively and depth resolved, the material composition and strain distribution in the weld zone. The results presented here relate to a FSW between AA2024 (single phase Al alloy) and AlSi10Mg (an alloy containing 10 wt.-% Si distributed in the form of Si particles in an Al matrix). The peak intensities from the Si phase can be used as an indicator for the mixing of the two welding partners since Si is only contained in the AlSi10Mg. The result from this evaluation is shown in figure 2a. For a better comprehension the welding tool is shown schematically. The grey shaded area corresponds to the position of the tool pin that was plunged into the material during the weld process. It can be observed that a significant amount of AA2024 is protruding about 5 mm in the AlSi10Mg side, while the AlSi10Mg material is dominant close to the weld centre. Large tensile strains of up to 1500x10-6 are observed in longitudinal direction. In transverse direction the residual strains are largely compressive. Furthermore the strain is rather homogeneous in depth. Only close to the anvil side of the plate (i.e. opposite the tool side) variations in depth occur. This could be explained by the different heat and material flow close to the anvil and around the tool tip. Future measurements over larger regions will in addition concentrate on the determination of the complete depth

  8. 3D Reconstruction from X-ray Fluoroscopy for Clinical Veterinary Medicine using Differential Volume Rendering

    Khongsomboon, Khamphong; Hamamoto, Kazuhiko; Kondo, Shozo

    3D reconstruction from ordinary X-ray equipment which is not CT or MRI is required in clinical veterinary medicine. Authors have already proposed a 3D reconstruction technique from X-ray photograph to present bone structure. Although the reconstruction is useful for veterinary medicine, the thechnique has two problems. One is about exposure of X-ray and the other is about data acquisition process. An x-ray equipment which is not special one but can solve the problems is X-ray fluoroscopy. Therefore, in this paper, we propose a method for 3D-reconstruction from X-ray fluoroscopy for clinical veterinary medicine. Fluoroscopy is usually used to observe a movement of organ or to identify a position of organ for surgery by weak X-ray intensity. Since fluoroscopy can output a observed result as movie, the previous two problems which are caused by use of X-ray photograph can be solved. However, a new problem arises due to weak X-ray intensity. Although fluoroscopy can present information of not only bone structure but soft tissues, the contrast is very low and it is very difficult to recognize some soft tissues. It is very useful to be able to observe not only bone structure but soft tissues clearly by ordinary X-ray equipment in the field of clinical veterinary medicine. To solve this problem, this paper proposes a new method to determine opacity in volume rendering process. The opacity is determined according to 3D differential coefficient of 3D reconstruction. This differential volume rendering can present a 3D structure image of multiple organs volumetrically and clearly for clinical veterinary medicine. This paper shows results of simulation and experimental investigation of small dog and evaluation by veterinarians.

  9. 3D reconstruction from X-ray fluoroscopy for clinical veterinary medicine using differential volume rendering

    3D reconstruction from ordinary X-ray equipment which is not CT or MRI is required in clinical veterinary medicine. Authors have already proposed a 3D reconstruction technique from X-ray photograph to present bone structure. Although the reconstruction is useful for veterinary medicine, the technique has two problems. One is about exposure of X-ray and the other is about data acquisition process. An x-ray equipment which is not special one but can solve the problems is X-ray fluoroscopy. Therefore, in this paper, we propose a method for 3D-reconstruction from X-ray fluoroscopy for clinical veterinary medicine. Fluoroscopy is usually used to observe a movement of organ or to identify a position of organ for surgery by weak X-ray intensity. Since fluoroscopy can output a observed result as movie, the previous two problems which are caused by use of X-ray photograph can be solved. However, a new problem arises due to weak X-ray intensity. Although fluoroscopy can present information of not only bone structure but soft tissues, the contrast is very low and it is very difficult to recognize some soft tissues. It is very useful to be able to observe not only bone structure but soft tissues clearly by ordinary X-ray equipment in the field of clinical veterinary medicine. To solve this problem, this paper proposes a new method to determine opacity in volume rendering process. The opacity is determined according to 3D differential coefficient of 3D reconstruction. This differential volume rendering can present a 3D structure image of multiple organs volumetrically and clearly for clinical veterinary medicine. This paper shows results of simulation and experimental investigation of small dog and evaluation by veterinarians. (author)

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

    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.

  11. 'Magnetic field'. X-ray diffraction

    The major subject of this paper is X-ray diffraction experiments in magnetic field using synchrotron radiation X-rays. This paper firstly introduces the basic experimental methods of X-ray diffraction, and then, the X-ray diffraction experiments in magnetic field that are carried out in Japan using four kinds of magnets such as permanent magnet, electromagnet, superconducting magnet, and pulsed high magnetic field magnet. Then, it introduces the following cases: (1) resonant X-ray diffraction experiment in magnetic field where the ordered state of electric dipole and magnetic octupole were observed in cerium hexaboride (CeB6) using a superconducting magnet, (2) ordered state of electric quadrupole of CeB6 using an electromagnet, and (3) pulsed magnetic field X-ray diffraction experiment that captured the change of lattice constant due to valence transition in the magnetic field application of Yb ions in YbInCu4 using a pulsed magnet. (A.O.)

  12. Statistical skull models from 3D X-ray images

    Berar, M; Bailly, G; Payan, Y; Berar, Maxime; Desvignes, Michel; Payan, Yohan

    2006-01-01

    We present 2 statistical models of the skull and mandible built upon an elastic registration method of 3D meshes. The aim of this work is to relate degrees of freedom of skull anatomy, as static relations are of main interest for anthropology and legal medicine. Statistical models can effectively provide reconstructions together with statistical precision. In our applications, patient-specific meshes of the skull and the mandible are high-density meshes, extracted from 3D CT scans. All our patient-specific meshes are registrated in a subject-shared reference system using our 3D-to-3D elastic matching algorithm. Registration is based upon the minimization of a distance between the high density mesh and a shared low density mesh, defined on the vertexes, in a multi resolution approach. A Principal Component analysis is performed on the normalised registrated data to build a statistical linear model of the skull and mandible shape variation. The accuracy of the reconstruction is under the millimetre in the shape...

  13. 3D diffraction tomography for visualization of contrast media

    Pai, Vinay M.; Stein, Ashley; Kozlowski, Megan; George, Ashvin; Kopace, Rael; Bennett, Eric; Auxier, Julie A.; Wen, Han

    2011-03-01

    In x-ray CT, the ability to selectively isolate a contrast agent signal from the surrounding soft tissue and bone can greatly enhance contrast visibility and enable quantification of contrast concentration. We present here a 3D diffraction tomography implementation for selectively retaining volumetric diffraction signal from contrast agent particles that are within a banded size range while suppressing the background signal from soft tissue and bone. For this purpose, we developed a CT implementation of a single-shot x-ray diffraction imaging technique utilizing gratings. This technique yields both diffraction and absorption images from a single grating-modulated projection image through analysis in the spatial frequency domain. A solution of iron oxide nano-particles, having very different x-ray diffraction properties from tissue, was injected into ex vivo chicken wing and in vivo rat specimens respectively and imaged in a 3D diffraction CT setup. Following parallel beam reconstruction, it is noted that while the soft tissue, bone and contrast media are observed in the absorption volume reconstruction, only the contrast media is observed in the diffraction volume reconstruction. This 3D diffraction tomographic reconstruction permits the visualization and quantification of the contrast agent isolated from the soft tissue and bone background.

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

    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.

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

    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

  16. X-ray diffraction microtomography using synchrotron radiation

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

    2001-01-01

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

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

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

    2011-07-01

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

  18. Coherent X-ray diffraction studies of mesoscopic materials

    Shabalin, Anatoly

    2015-12-15

    This thesis is devoted to three separate projects, which can be considered as independent. First, the dynamical scattering effects in the Coherent X-ray Diffractive Imaging (CXDI) method are discussed. Based on the simulation results, a straightforward method for correction for the refraction and absorption artifacts in the Bragg CXDI reconstruction is suggested. The second part summarizes the results of an Coherent X-ray Diffractive Imaging experiment with a single colloidal crystal grain. A remarkable result is that positions of individual particles in the crystal lattice have been resolved in three dimensions. The third project is devoted to X-ray diffraction experimental studies of structural evolution of colloidal crystalline films upon incremental heating. Based on the results of the analysis a model of structural evolution of a colloidal crystal upon heating on nanoscopic and mesoscopic length scales is suggested.

  19. Coherent X-ray diffraction studies of mesoscopic materials

    This thesis is devoted to three separate projects, which can be considered as independent. First, the dynamical scattering effects in the Coherent X-ray Diffractive Imaging (CXDI) method are discussed. Based on the simulation results, a straightforward method for correction for the refraction and absorption artifacts in the Bragg CXDI reconstruction is suggested. The second part summarizes the results of an Coherent X-ray Diffractive Imaging experiment with a single colloidal crystal grain. A remarkable result is that positions of individual particles in the crystal lattice have been resolved in three dimensions. The third project is devoted to X-ray diffraction experimental studies of structural evolution of colloidal crystalline films upon incremental heating. Based on the results of the analysis a model of structural evolution of a colloidal crystal upon heating on nanoscopic and mesoscopic length scales is suggested.

  20. Analytic 3D Imaging of Mammalian Nucleus at Nanoscale Using Coherent X-Rays and Optical Fluorescence Microscopy

    Song, Changyong; Takagi, Masatoshi; Park, Jaehyun; Xu, Rui; Gallagher-Jones, Marcus; Imamoto, Naoko; Ishikawa, Tetsuya

    2014-01-01

    Despite the notable progress that has been made with nano-bio imaging probes, quantitative nanoscale imaging of multistructured specimens such as mammalian cells remains challenging due to their inherent structural complexity. Here, we successfully performed three-dimensional (3D) imaging of mammalian nuclei by combining coherent x-ray diffraction microscopy, explicitly visualizing nuclear substructures at several tens of nanometer resolution, and optical fluorescence microscopy, cross confir...

  1. X-ray powder diffraction from solid deuterium

    Kawamura, H; Umemoto, S; Takemura, K; Ohishi, Y; Shimomura, O

    2002-01-01

    X-ray powder diffraction from solid deuterium was first observed under high pressure at SPring-8. At pressures up to 62 GPa and room temperature, three diffraction lines (100, 002, 101) of the hcp lattice were observed. The derived cell volume and the c/a ratio were consistent with single-crystal data. At 83 K and 94 GPa, three diffraction lines were also obtained and assigned to the hcp lattice.

  2. Photoluminescence and X-ray Diffraction of Distributed Bragg Reflector

    LI Lin; LI Yong-da; LIU Wen-li; LU Bin; JU Guo-xian; ZHANG Yong-ming; HAO Yong-qin; SU Wei; ZHONG Jing-chang

    2004-01-01

    Spectral and structural characteristics of distributed Bragg reflector (DBR) in vertical-cavity surface-emitting lasers were studied with photoluminescence and double- crystal X- ray diffraction measurement. The expected high quality epitaxial DBR structure was verified. In the X- ray double- crystal rocking curves of DBR the zeroth- order peak, the first and second order satellite peaks were measured.Splitting of diffraction peak appeared in the rocking curves was analyzed. The effects of introduced deep energy levels on the structural perfection and optical properties were discussed.

  3. 3D contrast-enhanced MR portography and direct X-ray portography: a correlation study

    Our objective was to compare 3D contrast-enhanced MR portography (3D CE MRP) on a 1.5-T MR imager with direct X-ray portography. Twenty-six consecutive patients underwent 3D CE MRP with in-plane resolution of 1.4 or 1.8 mm, and direct X-ray portography. The findings of these two methods were evaluated and compared. The main portal vein (PV), right PV with its anterior and posterior segmental branches, and left PV including its sagittal segment were shown clearly without diagnostic problem in all cases on MRP. The main PV appearance was accordant with MRP and X-ray. For intrahepatic PVs, the results agreed in 21 patients but disagreed in 5 patients. In 1 patient with a huge tumor in right liver, the right posterior PV was classified as occluded at MRP, but diffusely narrowed at X-ray. The findings of left intrahepatic PV were discordant in 3 patients with hepatocelluar carcinoma in the left lobe. The MRP demonstrated complete occlusion of the left PVs, whereas X-ray showed proximal narrowing and distal occlusion. In another patient with hepatocelluar carcinoma, a small non-occlusive thrombus involving the sagittal segment of the left PV was seen on MRP but not on X-ray. With demonstration of varices and portosystemic shunts, MRP showed results similar to those of X-ray, except one recanalized para-umbilical vein was excluded from the field of view at MRP due to the patient's limited ability of breathholding. The 3D CE MRP correlated well with direct X-ray portography in most cases, it was limited in distinguishing narrowing of an intrahepatic PV from occlusion, but it showed advantage in demonstrating small thrombus within PV. (orig.)

  4. 3D Hydrodynamic & Radiative Transfer Models of X-ray Emission from Colliding Wind Binaries

    Russell, Christopher M P; Owocki, Stanley P; Corcoran, Michael F; Hamaguchi, Kenji; Sugawara, Yasuharu

    2014-01-01

    Colliding wind binaries (CWBs) are unique laboratories for X-ray astrophysics. The massive stars in these systems possess powerful stellar winds with speeds up to $\\sim$3000 km s$^{-1}$, and their collision leads to hot plasma (up to $\\sim10^8$K) that emit thermal X-rays (up to $\\sim$10 keV). Many X-ray telescopes have observed CWBs, including Suzaku, and our work aims to model these X-ray observations. We use 3D smoothed particle hydrodynamics (SPH) to model the wind-wind interaction, and then perform 3D radiative transfer to compute the emergent X-ray flux, which is folded through X-ray telescopes' response functions to compare directly with observations. In these proceedings, we present our models of Suzaku observations of the multi-year-period, highly eccentric systems $\\eta$ Carinae and WR 140. The models reproduce the observations well away from periastron passage, but only $\\eta$ Carinae's X-ray spectrum is reproduced at periastron; the WR 140 model produces too much flux during this more complicated p...

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

    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

  6. Single-shot 3D structure determination of nanocrystals with femtosecond X-ray free electron laser pulses

    Xu, Rui; Song, Changyong; Rodriguez, Jose A; Huang, Zhifeng; Chen, Chien-Chun; Nam, Daewoong; Park, Jaehyun; Gallagher-Jones, Marcus; Kim, Sangsoo; Kim, Sunam; Suzuki, Akihiro; Takayama, Yuki; Oroguchi, Tomotaka; Takahashi, Yukio; Fan, Jiadong; Zou, Yunfei; Hatsui, Takaki; Inubushi, Yuichi; Kameshima, Takashi; Yonekura, Koji; Tono, Kensuke; Togashi, Tadashi; Sato, Takahiro; Yamamoto, Masaki; Nakasako, Masayoshi; Yabashi, Makina; Ishikawa, Tetsuya; Miao, Jianwei

    2013-01-01

    Coherent diffraction imaging (CDI) using synchrotron radiation, X-ray free electron lasers (X-FELs), high harmonic generation, soft X-ray lasers, and optical lasers has found broad applications across several disciplines. An active research direction in CDI is to determine the structure of single particles with intense, femtosecond X-FEL pulses based on diffraction-before-destruction scheme. However, single-shot 3D structure determination has not been experimentally realized yet. Here we report the first experimental demonstration of single-shot 3D structure determination of individual nanocrystals using ~10 femtosecond X-FEL pulses. Coherent diffraction patterns are collected from high-index-faceted nanocrystals, each struck by a single X-FEL pulse. Taking advantage of the symmetry of the nanocrystal, we reconstruct the 3D structure of each nanocrystal from a single-shot diffraction pattern at ~5.5 nm resolution. As symmetry exists in many nanocrystals and virus particles, this method can be applied to 3D st...

  7. Coherent diffraction imaging using focused hard X-rays

    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.

  8. Diffraction of X-ray pulse in crystals

    Baryshevsky, V. G.

    1999-01-01

    The X-ray radiation delay law dependence on the diffraction asymmetry parameters is analyzed. It is shown that the use of subpicosecond pulses allows to observe the time delay of pulse in crystal phenomenon and to investigate the delay law experimentally. It is also shown that pulse delay law depends on the quanta polarization.

  9. Powder X-ray diffraction study af alkali alanates

    Cao, Thao; Mosegaard Arnbjerg, Lene; Jensen, Torben René

    Powder X-ray diffraction study of alkali alanates Thao Cao, Lene Arnbjerg, Torben R. Jensen. Center for Materials Crystallography (CMC), Center for Energy Materials (CEM), iNANO and Department of Chemistry, Aarhus University, DK-8000, Denmark. Abstract: To meet the energy demand in the future...

  10. The three dimensional X-ray diffraction technique

    Juul Jensen, Dorte; Poulsen, Henning Friis

    2012-01-01

    This introductory tutorial describes the so called 3 dimensional X-ray diffraction (3DXRD) technique, which allows bulk non-destructive structural characterizations of crystalline materials. The motivations and history behind the development of this technique are described and its potentials...

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

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

    2010-01-01

    Starting from a general theory of time-resolved x-ray scattering, we derive a convenient expression for the diffraction signal based on a careful analysis of the relevant inelastic scattering processes. We demonstrate that the resulting inelastic limit applies to a wider variety of experimental c...

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

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

    2008-01-01

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

  13. X-Ray diffraction Investigation of Electrochemically Deposited Copper

    Pantleon, Karen; Jensen, Jens Dahl; Somers, Marcel A.J.

    2004-01-01

    by the determination of X-ray diffraction (XRD) pole figures and the calculation of the orientation distribution functions. XRD results are discussed in relation to the morphologies of the electrodeposits as investigated with light optical microscopy and correlated with the process parameters during electrodeposition....

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

    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)

  15. Computer Simulation and X-ray Diffraction of Nanocrystals

    2001-01-01

    X-ray diffraction of structure in nanocrystalline α-Fe and Cu was studied by atomistic simulation. Atomic position equilibrium was reached by using molecular dynamics method to simulate nanocrystalline structure with Finnis potentials to model interatomic interactions. lt was found that the boundary component exhibits short-range order, and the distortion in crystalline component increases with the decrease of grain size.

  16. A Practical Method of Simulating X-Ray Diffraction

    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)

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

    Weichel, Steen; Grey, Francois; Rasmussen, Kurt;

    2000-01-01

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

  18. X-ray diffraction pattern of powder rhenium semiheptaoxide

    The X-ray diffraction pattern of Re2O7 powder at 110-115 deg C under the conditions excluding absorption of the air moisture by the sample is obtained. Rhombic lattice parameters a=12.52; b=15.26; c=5.45 A are calculated

  19. Oxygen precipitation studied by x-ray diffraction techniques

    Meduňa, M.; Caha, O.; Růžička, J.; Bernatová, S.; Svoboda, Milan; Buršík, Jiří

    178 -179, - (2011), s. 325-330. ISSN 1012-0394 R&D Projects: GA ČR(CZ) GA202/09/1013 Institutional research plan: CEZ:AV0Z20410507 Keywords : Czochralski silicon * oxygen precipitates * x-ray Laue diffraction Subject RIV: BM - Solid Matter Physics ; Magnetism

  20. Evaluation of a new method for stenosis quantification from 3D x-ray angiography images

    Betting, Fabienne; Moris, Gilles; Knoplioch, Jerome; Trousset, Yves L.; Sureda, Francisco; Launay, Laurent

    2001-05-01

    A new method for stenosis quantification from 3D X-ray angiography images has been evaluated on both phantom and clinical data. On phantoms, for the parts larger or equal to 3 mm, the standard deviation of the measurement error has always found to be less or equal to 0.4 mm, and the maximum measurement error less than 0.17 mm. No clear relationship has been observed between the performances of the quantification method and the acquisition FoV. On clinical data, the 3D quantification method proved to be more robust to vessel bifurcations than its 3D equivalent. On a total of 15 clinical cases, the differences between 2D and 3D quantification were always less than 0.7 mm. The conclusion is that stenosis quantification from 3D X-4ay angiography images is an attractive alternative to quantification from 2D X-ray images.

  1. Single-Shot Femtosecond X-ray Diffraction from Randomly Oriented Ellipsoidal Nanoparticles

    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 (250 nm x 50 nm) 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.

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

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

    2010-01-01

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

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

    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

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

    Antunes, A. [Departamento de Fisica Aplicada, USP, CP 66318, 05315-970 Sao Paulo, SP (Brazil)]. E-mail: antunes@if.usp.br; Hoennicke, M.G. [LORXI, Departamento de Fisica, Universidade Federal do Parana, Curitiba (Brazil); Safatle, A.M.V. [Faculdade de Medicina Veterinaria e Zootecnia, USP, 05508-900 Sao Paulo, SP (Brazil); Cusatis, C. [LORXI, Departamento de Fisica, Universidade Federal do Parana, Curitiba (Brazil); Moraes Barros, P.S. [Faculdade de Medicina Veterinaria e Zootecnia, USP, 05508-900 Sao Paulo, SP (Brazil); Morelhao, S.L. [Departamento de Fisica Aplicada, USP, CP 66318, 05315-970 Sao Paulo, SP (Brazil)

    2005-08-15

    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.

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

    McBride, L

    2000-01-01

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

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

    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.

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

    Ito, M

    2002-01-01

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

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

    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.

  9. Characterisation of the deformation mechanisms in hcp metals by combined use of X-ray imaging and diffraction techniques

    Nervo, Laura

    2015-01-01

    We envisage a fundamental study of the physical mechanisms (dislocation slip versus deformation twinning) involved in plastic deformation of hexagonal close-packed (HCP) metals like titanium and magnesium. A novel combination of X-ray imaging and diffraction techniques, termed X-ray diffraction contrast tomography (DCT), will be used to investigate details of the deformation process in the bulk of polycrystalline specimen. DCT provides access to the position, 3D shape, (average) orientation a...

  10. 3D ablation catheter localisation using individual C-arm x-ray projections

    Haase, C.; Schäfer, D.; Dössel, O.; Grass, M.

    2014-11-01

    Cardiac ablation procedures during electrophysiology interventions are performed under x-ray guidance with a C-arm imaging system. Some procedures require catheter navigation in complex anatomies like the left atrium. Navigation aids like 3D road maps and external tracking systems may be used to facilitate catheter navigation. As an alternative to external tracking a fully automatic method is presented here that enables the calculation of the 3D location of the ablation catheter from individual 2D x-ray projections. The method registers a high resolution, deformable 3D attenuation model of the catheter to a 2D x-ray projection. The 3D localization is based on the divergent beam projection of the catheter. On an individual projection, the catheter tip is detected in 2D by image filtering and a template matching method. The deformable 3D catheter model is adapted using the projection geometry provided by the C-arm system and 2D similarity measures for an accurate 2D/3D registration. Prior to the tracking and registration procedure, the deformable 3D attenuation model is automatically extracted from a separate 3D cone beam CT reconstruction of the device. The method can hence be applied to various cardiac ablation catheters. In a simulation study of a virtual ablation procedure with realistic background, noise, scatter and motion blur an average 3D registration accuracy of 3.8 mm is reached for the catheter tip. In this study four different types of ablation catheters were used. Experiments using measured C-arm fluoroscopy projections of a catheter in a RSD phantom deliver an average 3D accuracy of 4.5 mm.

  11. Three-dimensional coherent X-ray diffraction imaging of a whole, frozen-hydrated cell

    Rodriguez, Jose A; Chen, Chien-Chun; Huang, Zhifeng; Jiang, Huaidong; Raines, Kevin S; Nam, Daewoong; Chen, Allan L; Pryor, A J; Wiegart, Lutz; Song, Changyong; Madsen, Anders; Chushkin, Yuriy; Zontone, Federico; Bradley, Peter J; Miao, Jianwei

    2014-01-01

    A structural understanding of whole cells in three dimensions at high spatial resolution remains a significant challenge and, in the case of X-rays, has been limited by radiation damage. By alleviating this limitation, cryogenic coherent diffraction imaging (cryo-CDI) could bridge the important resolution gap between optical and electron microscopy in bio-imaging. Here, we report for the first time 3D cryo-CDI of a whole, frozen-hydrated cell - in this case a Neospora caninum tachyzoite - using 8 keV X-rays. Our 3D reconstruction reveals the surface and internal morphology of the cell, including its complex, polarized sub-cellular architecture with a 3D resolution of ~75-100 nm, which is presently limited by the coherent X-ray flux and detector size. Given the imminent improvement in the coherent X-ray flux at the facilities worldwide, our work forecasts the possibility of routine 3D imaging of frozen-hydrated cells with spatial resolutions in the tens of nanometres.

  12. Development of 2D, pseudo 3D and 3D x-ray imaging for early diagnosis of breast cancer and rheumatoid arthritis

    By using plane-wave x-rays with synchrotron radiation refraction-based x-ray medical imaging can be used to visualize soft tissue, as reported in this paper. This method comprises two-dimensional (2D) x-ray dark-field imaging (XDFI), the tomosynthesis of pseudo 3D (sliced) x-ray imaging by the adoption of XDFI and 3D x-ray imaging by utilizing a newly devised algorithm. We aim to make contribution to the early diagnosis of breast cancer, which is a major cancer among women, and rheumatoid arthritises which cannot be detected in its early stages. (author)

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

    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.

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

    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

  15. 3-D Multiphase Segmentation of X-Ray Micro Computed Tomography Data of Geologic Materials

    Tuller, M.; Kulkarni, R.; Fink, W.

    2011-12-01

    Advancements of noninvasive imaging methods such as X-Ray Computed Tomography (CT) led to a recent surge of applications in Geoscience. While substantial efforts and resources have been devoted to advance CT technology and micro-scale analysis, the development of a stable 3-D multiphase image segmentation method applicable to large datasets is lacking. To eliminate the need for wet/dry or dual energy scans, image alignment, and subtraction analysis, commonly applied in synchrotron X-Ray micro CT, a segmentation method based on a Bayesian Markov Random Field (MRF) framework amenable to true 3-D multiphase processing was developed and evaluated. Furthermore, several heuristic and deterministic combinatorial optimization schemes required to solve the labeling problem of the MRF image model were implemented and tested for computational efficiency and their impact on segmentation results. Test results for natural and artificial porous media datasets demonstrate great potential of the MRF image model for 3-D multiphase segmentation.

  16. Element-specific X-ray phase tomography of 3D structures at the nanoscale.

    Donnelly, Claire; Guizar-Sicairos, Manuel; Scagnoli, Valerio; Holler, Mirko; Huthwelker, Thomas; Menzel, Andreas; Vartiainen, Ismo; Müller, Elisabeth; Kirk, Eugenie; Gliga, Sebastian; Raabe, Jörg; Heyderman, Laura J

    2015-03-20

    Recent advances in fabrication techniques to create mesoscopic 3D structures have led to significant developments in a variety of fields including biology, photonics, and magnetism. Further progress in these areas benefits from their full quantitative and structural characterization. We present resonant ptychographic tomography, combining quantitative hard x-ray phase imaging and resonant elastic scattering to achieve ab initio element-specific 3D characterization of a cobalt-coated artificial buckyball polymer scaffold at the nanoscale. By performing ptychographic x-ray tomography at and far from the Co K edge, we are able to locate and quantify the Co layer in our sample to a 3D spatial resolution of 25 nm. With a quantitative determination of the electron density we can determine that the Co layer is oxidized, which is confirmed with microfluorescence experiments. PMID:25839287

  17. X-ray scattering in the elastic regime as source for 3D imaging reconstruction technique

    Kocifaj, Miroslav; Mego, Michal

    2015-11-01

    X-ray beams propagate across a target object before they are projected onto a regularly spaced array of detectors to produce a routine X-ray image. A 3D attenuation coefficient distribution is obtained by tomographic reconstruction where scattering is usually regarded as a source of parasitic signals which increase the level of electromagnetic noise that is difficult to eliminate. However, the elastically scattered radiation could be a valuable source of information, because it can provide a 3D topology of electron densities and thus contribute significantly to the optical characterization of the scanned object. The scattering and attenuation data form a complementary base for concurrent retrieval of both electron density and attenuation coefficient distributions. In this paper we developed the 3D reconstruction method that combines both data inputs and produces better image resolution compared to traditional technology.

  18. X-ray diffraction from single GaAs nanowires

    Biermanns, Andreas

    2012-11-12

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

  19. 3D Radio and X-Ray Modeling and Data Analysis Software: Revealing Flare Complexity

    Nita, Gelu M; Kuznetsov, Alexey A; Kontar, Eduard P; Gary, Dale E

    2014-01-01

    We have undertaken a major enhancement of our IDL-based simulation tools developed earlier for modeling microwave and X-ray emission. The object-based architecture provides an interactive graphical user interface that allows the user to import photospheric magnetic field maps and perform magnetic field extrapolations to almost instantly generate 3D magnetic field models, to investigate the magnetic topology of these models by interactively creating magnetic field lines and associated magnetic flux tubes, to populate the flux tubes with user-defined nonuniform thermal plasma and anisotropic, nonuniform, nonthermal electron distributions; to investigate the spatial and spectral properties of radio and X-ray emission calculated from the model, and to compare the model-derived images and spectra with observational data. The application integrates shared-object libraries containing fast gyrosynchrotron emission codes developed in FORTRAN and C++, soft and hard X-ray codes developed in IDL, a FORTRAN-based potentia...

  20. Lattice rotations of individual bulk grains. Part 1: 3D X-ray characterization

    Poulsen, H.F.; Margulies, L.; Schmidt, S.;

    2003-01-01

    Three-dimensional X-ray diffraction has been applied to characterise the plastic deformation of individualgrains deeply embedded in a 99.6% pure aluminium specimen. The specimen is 4 mm thick with an average grain size of 75 μm. The average latticerotation for each grain as well as the degree of...

  1. 3D localization of electrophysiology catheters from a single x-ray cone-beam projection

    Purpose: X-ray images allow the visualization of percutaneous devices such as catheters in real time but inherently lack depth information. The provision of 3D localization of these devices from cone beam x-ray projections would be advantageous for interventions such as electrophysiology (EP), whereby the operator needs to return a device to the same anatomical locations during the procedure. A method to achieve real-time 3D single view localization (SVL) of an object of known geometry from a single x-ray image is presented. SVL exploits the change in the magnification of an object as its distance from the x-ray source is varied. The x-ray projection of an object of interest is compared to a synthetic x-ray projection of a model of said object as its pose is varied. Methods: SVL was tested with a 3 mm spherical marker and an electrophysiology catheter. The effect of x-ray acquisition parameters on SVL was investigated. An independent reference localization method was developed to compare results when imaging a catheter translated via a computer controlled three-axes stage. SVL was also performed on clinical fluoroscopy image sequences. A commercial navigation system was used in some clinical image sequences for comparison. Results: SVL estimates exhibited little change as x-ray acquisition parameters were varied. The reproducibility of catheter position estimates in phantoms denoted by the standard deviations, (σx, σy, σz) = (0.099 mm,  0.093 mm,  2.2 mm), where x and y are parallel to the detector plane and z is the distance from the x-ray source. Position estimates (x, y, z) exhibited a 4% systematic error (underestimation) when compared to the reference method. The authors demonstrated that EP catheters can be tracked in clinical fluoroscopic images. Conclusions: It has been shown that EP catheters can be localized in real time in phantoms and clinical images at fluoroscopic exposure rates. Further work is required to characterize performance in clinical

  2. 3D localization of electrophysiology catheters from a single x-ray cone-beam projection

    Robert, Normand, E-mail: normand.robert@sri.utoronto.ca; Polack, George G.; Sethi, Benu; Rowlands, John A. [Physical Sciences, Sunnybrook Research Institute, 2075 Bayview Avenue, Toronto, Ontario M4N 3M5 (Canada); Crystal, Eugene [Division of Cardiology, Sunnybrook Health Sciences Centre, 2075 Bayview Avenue, Toronto, Ontario M4N 3M5 (Canada)

    2015-10-15

    Purpose: X-ray images allow the visualization of percutaneous devices such as catheters in real time but inherently lack depth information. The provision of 3D localization of these devices from cone beam x-ray projections would be advantageous for interventions such as electrophysiology (EP), whereby the operator needs to return a device to the same anatomical locations during the procedure. A method to achieve real-time 3D single view localization (SVL) of an object of known geometry from a single x-ray image is presented. SVL exploits the change in the magnification of an object as its distance from the x-ray source is varied. The x-ray projection of an object of interest is compared to a synthetic x-ray projection of a model of said object as its pose is varied. Methods: SVL was tested with a 3 mm spherical marker and an electrophysiology catheter. The effect of x-ray acquisition parameters on SVL was investigated. An independent reference localization method was developed to compare results when imaging a catheter translated via a computer controlled three-axes stage. SVL was also performed on clinical fluoroscopy image sequences. A commercial navigation system was used in some clinical image sequences for comparison. Results: SVL estimates exhibited little change as x-ray acquisition parameters were varied. The reproducibility of catheter position estimates in phantoms denoted by the standard deviations, (σ{sub x}, σ{sub y}, σ{sub z}) = (0.099 mm,  0.093 mm,  2.2 mm), where x and y are parallel to the detector plane and z is the distance from the x-ray source. Position estimates (x, y, z) exhibited a 4% systematic error (underestimation) when compared to the reference method. The authors demonstrated that EP catheters can be tracked in clinical fluoroscopic images. Conclusions: It has been shown that EP catheters can be localized in real time in phantoms and clinical images at fluoroscopic exposure rates. Further work is required to characterize

  3. X-ray and neutron diffraction studies of chalcocite oxidation

    Full text: The mineral chalcocite (Cu2S), which is often found in the enriched zone of sulphide deposits, is an important source of copper. The oxidation behaviour of chalcocite is of interest in terms of the mineral exploration technology and also for understanding the behaviour of the mineral under roasting conditions. Recently, the oxidation of chalcocite was the subject of a study by Dunn et al (1994) involving the use of thermal analysis, scanning electron microscopy, electron probe microanalysis, powder x-ray diffraction (XRD) and Fourier transform spectroscopy. The study indicated that the following transformations are likely to occur: at 430-490 deg C, partial conversion of Cu2S to Cu2O and CuSO4 via Cu1.96S and Cu1.80S; at 490-590 deg C, further conversion of Cu2S to Cu2O, CuO CuSO4 and CuSO4; and at 590-820 deg C, Cu2O, CuO CuSO4 and CuSO4 to CuO. In this study, the oxidation of chalcocite was analysed from a crystallographic perspective. Ambient x-ray diffraction and in-situ neutron diffraction were used to determine the phases present, at various temperatures, as oxidation progressed. Ambient x-ray experiments involved heating chalcocite powder in an air stream, to a target temperature, cooling it to room temperature in a nitrogen stream, and analysing by Bragg-Brentano x-ray powder diffractometry. In situ neutron experiments consisted of, powdered chalcocite being heated in an air stream to various target temperatures, and then held in a nitrogen stream at the given temperature while Medium Resolution Powder Diffractometry (EPD) was performed. Rietveld modelling of the x-ray and neutron data was used to confirm the phase identifications made by search/match analysis, and to then map the variations in phase levels with temperature as the oxidation progresses through various phase transformations. The talk will consider the results obtained from the study with particular reference to the identification of previously undetected phases, and the differences

  4. X-ray diffraction at Bragg angles around π/2

    X-ray diffraction at Bragg angles around π/2 is studied from the theoretical and experimental points of view. The proposed corrections to the dynamical theory in the θβ ≅ π/2 cases, has been reviewed showing the equivalence between two formalisms leading to a corrected expression for the dependence of the angular parameter y with the angle of incidence. An expression for y valid in the conventional and θ β ≅ π/2 cases has been obtained. A general expression for Bragg law and for energy resolution after a Bragg diffraction was also deduced. (author)

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

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

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

    Gulden, Johannes

    2013-03-15

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

  7. 3D global estimation and augmented reality visualization of intra-operative X-ray dose.

    Rodas, Nicolas Loy; Padoy, Nicolas

    2014-01-01

    The growing use of image-guided minimally-invasive surgical procedures is confronting clinicians and surgical staff with new radiation exposure risks from X-ray imaging devices. The accurate estimation of intra-operative radiation exposure can increase staff awareness of radiation exposure risks and enable the implementation of well-adapted safety measures. The current surgical practice of wearing a single dosimeter at chest level to measure radiation exposure does not provide a sufficiently accurate estimation of radiation absorption throughout the body. In this paper, we propose an approach that combines data from wireless dosimeters with the simulation of radiation propagation in order to provide a global radiation risk map in the area near the X-ray device. We use a multi-camera RGBD system to obtain a 3D point cloud reconstruction of the room. The positions of the table, C-arm and clinician are then used 1) to simulate the propagation of radiation in a real-world setup and 2) to overlay the resulting 3D risk-map onto the scene in an augmented reality manner. By using real-time wireless dosimeters in our system, we can both calibrate the simulation and validate its accuracy at specific locations in real-time. We demonstrate our system in an operating room equipped with a robotised X-ray imaging device and validate the radiation simulation on several X-ray acquisition setups. PMID:25333145

  8. Design and fabrication of micro X-ray diffraction system

    Park, Yang Soon; Han, Sun Ho; Kim, Jong Goo; Jee, Kwang Yong

    2006-10-15

    It has been observed that microstructure changes occur at the pellet periphery(rim) of the fuel at very high burn-up. Despite its narrow range (below some hundreds microns in depth), this peripheral region(rim) determines the behaviour of nuclear fuel. To determine lattice parameter with XRD at intervals as small as 30-50 {mu} m in radial direction of irradiated fuel samples, a micro X-ray diffraction system was designed and fabricated. This report describes the micro X-ray diffraction system consisted of an X-ray microbeam alignment system and a sample micro translation system, its characterization, and its performance test through the analysis for the micro region of some specimens. This system will be set in a radiation shielded glove box, and then used for analysis of lattice parameter change and the phase change at intervals as small as 30-50 {mu} m in radial direction of the rim of an irradiated fuel sample and a fuel cladding.

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

    Robert M. Lawrence

    2015-07-01

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

  10. Gamma/x-ray linear pushbroom stereo for 3D cargo inspection

    Zhu, Zhigang; Hu, Yu-Chi

    2006-05-01

    For evaluating the contents of trucks, containers, cargo, and passenger vehicles by a non-intrusive gamma-ray or X-ray imaging system to determine the possible presence of contraband, three-dimensional (3D) measurements could provide more information than 2D measurements. In this paper, a linear pushbroom scanning model is built for such a commonly used gamma-ray or x-ray cargo inspection system. Accurate 3D measurements of the objects inside a cargo can be obtained by using two such scanning systems with different scanning angles to construct a pushbroom stereo system. A simple but robust calibration method is proposed to find the important parameters of the linear pushbroom sensors. Then, a fast and automated stereo matching algorithm based on free-form deformable registration is developed to obtain 3D measurements of the objects under inspection. A user interface is designed for 3D visualization of the objects in interests. Experimental results of sensor calibration, stereo matching, 3D measurements and visualization of a 3D cargo container and the objects inside, are presented.

  11. Crystallite size determination by x-ray diffraction

    Full text: Particle sizing problem arises in many fields of science, technology and material production. Methods based on X-ray diffraction lines broadening cover size interval of 10-100 nm and are well documented. Larger crystallites demonstrate no line broadening and require alternative methods for size determination. When crystallites are relatively large (10-500 mkm) and a small volume of the sample is irradiated the diffraction pattern exhibits discrete spots instead of continuous diffraction lines. We base our approach on the linear correlation between average crystallite's size and diffraction spots dimensions which is valid for crystallite size above 5 mkm. Thus the aim of this work is to extract the crystallite size distribution function from the analysis of the spot size distribution

  12. New developments for 3D CT at high X-ray energy

    CT is well suited both for measurements and for flaw detection in cast metal products which as a rule have a complex shape and internal caverns. Currently available tomographs for 3D scanning of large objects still have shortcomings. Line detectors - normally operated with a 450 kV X-ray source - are slow. Systems with detector panels normally have 225 kV microfocus tubes which provide insufficient power. The microfocus tube cannot be replaced by a 450 kV tube as scattered radiation at higher energies will considerably reduce the image quality of the tomograms. In the context of European research projects during the past few years, Empa developed new methods for faster data acquisition with line detector systems and correction of scattered radiation for CT with conical beams and with panel detectors. The contribution outlines the state of the art and also presents new trends, especially for fast 3D volume scanning with high X-ray energy

  13. NDE of spacecraft materials using 3D Compton backscatter x-ray imaging

    Burke, E. R.; Grubsky, V.; Romanov, V.; Shoemaker, K.

    2016-02-01

    We present the results of testing of the NDE performance of a Compton Imaging Tomography (CIT) system for single-sided, penetrating 3D inspection. The system was recently developed by Physical Optics Corporation (POC) and delivered to NASA for testing and evaluation. The CIT technology is based on 3D structure mapping by collecting the information on density profiles in multiple object cross sections through hard x-ray Compton backscatter imaging. The individual cross sections are processed and fused together in software, generating a 3D map of the density profile of the object which can then be analyzed slice-by-slice in x, y, or z directions. The developed CIT scanner is based on a 200-kV x-ray source, flat-panel x-ray detector (FPD), and apodized x-ray imaging optics. The CIT technology is particularly well suited to the NDE of lightweight aerospace materials, such as the thermal protection system (TPS) ceramic and composite materials, micrometeoroid and orbital debris (MMOD) shielding, spacecraft pressure walls, inflatable habitat structures, composite overwrapped pressure vessels (COPVs), and aluminum honeycomb materials. The current system provides 3D localization of defects and features with field of view 20x12x8 cm3 and spatial resolution ˜2 mm. In this paper, we review several aerospace NDE applications of the CIT technology, with particular emphasis on TPS. Based on the analysis of the testing results, we provide recommendations for continued development on TPS applications that can benefit the most from the unique capabilities of this new NDE technology.

  14. Bone histomorphometric quantification by X-ray phase contrast and transmission 3D SR microcomputed tomography

    Full text: Conventional histomorphometry is an important method for quantitative evaluation of bone microstructure. X-ray computed tomography is a noninvasive technique, which can be used to evaluate histomorphometric indices. In this technique, the output 3D images are used to quantify the whole sample, differently from the conventional one, in which the quantification is performed in 2D slices and extrapolated for 3D case. Looking for better resolutions and visualization of soft tissues, X-ray phase contrast imaging technique was developed. The objective of this work was to perform histomorphometric quantification of human cancellous bone using 3D synchrotron X ray computed microtomography, using two distinct techniques: transmission and phase contrast, in order to compare the results and evaluate the viability of applying the same methodology of quantification for both technique. All experiments were performed at the ELETTRA Synchrotron Light Laboratory in Trieste (Italy). MicroCT data sets were collected using the CT set-up on the SYRMEP (Synchrotron Radiation for Medical Physics) beamline. Results showed that there is a better correlation between histomorphometric parameters of both techniques when morphological filters had been used. However, using these filters, some important information given by phase contrast are lost and they shall be explored by new techniques of quantification

  15. 3D X-ray microscopy: image formation, tomography and instrumentation

    Selin, Mårten

    2016-01-01

    Tomography in soft X-ray microscopy is an emerging technique for obtaining quantitative 3D structural information about cells. One of its strengths, compared with other techniques, is that it can image intact cells in their near-native state at a few 10 nm’s resolution, without staining. However, the methods for reconstructing 3D-data rely on algorithms that assume projection data, which the images are generally not due to the imaging systems’ limited depth of focus. To bring out the full pot...

  16. In situ x-ray diffraction studies of three-dimensional C60 polymers

    In situ investigations into the P/T field of C60 fullerene were performed using energy-dispersive x-ray diffraction techniques. Isobars were obtained at 11 and 9 GPa accompanied by isotherms at 750 and 800 K with pressure reaching 13 GPa. The P/T history and pressure isotropy were investigated with the aim of optimizing conditions for 3D polymer formation. Confirmation of the formation of 3D polymers was performed in situ; however, the reclaimed sample did not exhibit the expected high hardness value, due to depolymerization on pressure release. Isotropy in the pressure field promoted formation and retention of the face-centred-cubic structure

  17. X-ray Mirage Diffraction and Its Interference Fringes

    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.

  18. The three dimensional X-ray diffraction technique

    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.

  19. The three dimensional X-ray diffraction technique

    Jensen, D. Juul, E-mail: doje@dtu.dk [Danish Chinese Center for Nanometals, Materials Science and Advanced Characterization Section, Department of Wind Energy, Technical University of Denmark, Riso Campus (Denmark); Poulsen, H.F. [Department of Physics, Technical University of Denmark, Lyngby Campus (Denmark)

    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.

  20. Ab initio structure determination via powder X-ray diffraction

    Digamber G Porob; T N Guru Row

    2001-10-01

    Structure determination by powder X-ray diffraction data has gone through a recent surge since it has become important to get to the structural information of materials which do not yield good quality single crystals. Although the method of structure completion when once the starting model is provided is facile through the Rietveld refinement technique, the structure solution ab initio os still not push-button technology. In this article a survey of the recent development in this area is provided with an illustration of the structure determination of -NaBi3V2O10.

  1. Automation of a Guinier camera for X-ray diffraction

    The automation of a Guinier X-ray diffraction camera is discussed. The photographic plate in the conventional setup has been replaced by a curved proportional counter (CPC) which has an electronic readout system. As a result the recording time has been reduced from a few hours to a few minutes. The construction and optimum dimensions of the CPC are discussed and the most essential parts of the readout electronics are highlighted. A linewidth of 200 μm FWHM and an accuracy of 30 μm are achieved. 45 refs.; 53 figs.; 4 tabs

  2. Resonant X-ray diffraction: Basic theoretical principles

    We present the main steps governing the theory of resonant X-ray diffraction (RXD). We focus on the derivation of the anomalous scattering amplitude from perturbation theory and starting from the low-energy expansion of the Dirac Hamiltonian. We give the main ingredients of the multipolar expansion in term of electric and magnetic transitions. We also show the expansion in terms of scattering tensors of the material. We end by giving the RXD formula necessary to simulate in practice this spectroscopy. (authors)

  3. Structural science using neutron and x-ray diffraction

    I was awarded a prize by The Japanese Society for Neutron Science at 2009. The main topic of the title is the contribution to the structural science using neutron and x-ray. Special emphasis was adopted for the development of instrumentations. In this paper, the idea of structural science is given, and the importance of the crystal and magnetic structures for material properties will be discussed. Starting from my personal history for development of instrumentations on diffraction studies, I will touch the scientific results. At the last part, future development on this field will be overlooked. (author)

  4. Ultrafast X-Ray Diffraction of Heterogeneous Solid Hydrogen

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

    2015-08-19

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

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

    Levitan, Abraham [SLAC National Accelerator Lab., Menlo Park, CA (United States)

    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.

  6. X-ray diffraction analysis of InAs nanowires

    Semiconductor nanowires have attracted great interest as building blocks for future electronic and optoelectronic devices. The variability of the growth process opens the opportunity to control and combine the various properties tailoring for specific application. It was shown that the electrical and optical characteristics of the nanowires are strongly connected with their structure. Despite intensive research in this field, the growth process is still not fully understood. In particular, extensive real structure investigations are required. Most of the reports dedicated on the structural researches are based on the results of scanning electron microscopy (SEM) or transmission electron microscopy (TEM). SEM provides an image of the surface with nanostructures and is mainly used to describe the morphology of the sample, but it does not bring information about the internal structure, phase composition and defect structure. At the same time, the internal structure can be examined by TEM down to atomic scale. TEM image of good quality are very expensive due to the efforts in sample preparation and in localisation of a single object. All these aspects make the statistical structural analysis difficult. In the present work, X-ray diffraction analysis has been applied for structural investigation of InAs nanowires grown by different techniques. Using various X-ray diffraction geometries, the nanowire systems were investigated in terms of the lattice parameters, phase composition, strains and displacement fields and stacking defects. In particular, realizing grazing incidence diffraction and controlling the penetration depth of X-ray beam, we characterized sample series grown by Au-assisted metal organic phase epitaxy on GaAs [111]B substrate with different growth time. According to the results of SEM and X-ray investigations, a model of the growth process has been proposed. A more detailed analysis was performed on InAs nanowires grown by molecular beam epitaxy (MBE) on

  7. Diffraction peaks restoration and extraction in energy dispersive X-ray diffraction

    This paper proposes a method to restore energy dispersive X-ray diffraction (EDXRD) spectra and to extract diffraction peaks. It follows a maximum a posteriori approach using a physical model of the formation of the EDXRD data to remove blur caused by both the detector and the coarse angular resolution of X-ray tube based EDXRD setup. It separates peaks due to the diffraction by crystalline material from a continuous background. Tested on real data (graphite and NaCl), our algorithm achieved to detect diffraction peaks with a good precision (about 1 keV depending on the peak position) even at high energy where very few photons were measured.

  8. Characterization of Brazilian asphalt using X-ray diffraction

    Asphalt is a sticky, black and highly viscous liquid or semi-solid that is presented in most crude petroleum and in some natural deposits. The X ray diffraction can give valuable information over the characteristics of a material. Thus, the X-ray diffraction (XRD) method was employed to investigate parameters that characterize and differentiate asphalt groups (Boscan, CAP20, CAP40, CAP50/60, CAP50/70 and CAP85/100). The scattering measurements were carried out in θ-2θ reflection geometry using a powder diffractometer Shimadzu XRD-6000 at the Nuclear Instrumentation Laboratory, Brazil. Scans were typically done from 8 deg to 28 deg every 0.05. The parameters analyzed were: FWHM, peak area, peak center, peak height, left half width and right half width. Thus, in this study, scattering profiles from different asphalt groups were carefully measured in order to establish characteristic signatures of these materials. The results indicate that by using three parameters (peak centroid, peak area and peak intensity) it is possible to characterize and differentiate the asphalt. (author)

  9. X-ray diffraction line profile analysis of nanocrystalline graphite

    The structure evolution to nanocrystalline graphite produced by ball milling in n-dodecane has been studied by Fourier analysis of broadened X-ray diffraction line profiles according to double-Voigt method. The Fourier analysis gave size and strain distributions of the coherently diffracting domains (X-ray crystallite size) and root-mean-square-strain (rmss) and their average values. The precursor graphite was defined by average crystal sizes of about hundreds of nanometers, measured along the in-plane and out-of-plane directions, and low rmss value of 0.38 x 10-3. During milling, the average crystallite sizes of graphite decreased to about 6 and 43 nm along the out-of-plane and in-plane directions, respectively. Correspondingly, the rmss of milled graphite increased to 6.54 x 10-3. Analysis of the out-of-plane to in-plane crystallite size ratios showed that the crystallites became progressively thinner and flatter. A linear relationship between rmss and reciprocal crystallite size along the stacking axis revealed that size of disordered boundary regions gradually increased at the expense of ordered crystalline regions. A model describing crystalline-nanocrystalline transformation of graphite along different crystallographic axis was formulated and used to discuss the experimental data. It was concluded that a distortion-controlled process is responsible for the crystalline-nanocrystalline transformation of graphite milled in n-dodecane

  10. Microstructure analysis of nanocrystalline powders by X-ray diffraction

    The use of X-ray diffraction line profile analysis for the study of nanocrystalline powders is described. The fundamentals of the theory are presented in terms of crystallite/domain size, size distribution, lattice distortion, dislocations density and stacking faults. Line profile parameters and the methods of pattern fitting introduced to overcome the diffraction-line overlap problem are discussed. The approaches based of the integral breadth of the measured line profiles and the Fourier method are discussed. In addition, simplified approaches are also commented. Representative examples are selected to illustrate various cases of microstructure, such as nanomaterials with strain-free spherical nano crystallites, strain-free crystallites with anisotropic crystallite shape, anisotropic crystallites with microstrains and spherical crystallites with dislocation densities and crystallite size distributions. (author)

  11. Application of 3D X-ray CT data sets to finite element analysis

    Finite Element Modeling (FEM) is becoming more important as industry drives toward concurrent engineering. A fundamental hindrance to fully exploiting the power of FEM is the human effort required to acquire complex part geometry, particularly as-built geometry, as a FEM mesh. Many Quantitative Non Destructive Evaluation (QNDE) techniques that produce three-dimensional (3D) data sets provide a substantial reduction in the effort required to apply FEM to as-built parts. This paper describes progress at LLNL on the application of 3D X-ray computed tomography (CT) data sets to more rapidly produce high-quality FEM meshes of complex, as-built geometries. Issues related to the volume segmentation of the 3D CT data as well as the use of this segmented data to tailor generic hexahedral FEM meshes to part specific geometries are discussed. The application of these techniques to FEM analysis in the medical field is reported here

  12. Quantification of rutile in anatase by X-ray diffraction

    Nowadays the discovering of new and better materials required in all areas of the industry has been lead to the human being to introduce him to this small and great world. The crystalline materials, have properties markedly directional. When it is necessary to realize a quantitative analysis to these materials the task is not easy. The main objective of this work is the research of a real problem, its solution and perfecting of a technique involving the theoretical and experimental principles which allow the quantification of crystalline phases. The chapter 1 treats about the study of crystalline state during the last century, by means of the X-ray diffraction technique. The chapter 2 studies the nature and production of X-rays, the chapter 3 expounds the principles of the diffraction technique which to carry out when it is satisfied the Bragg law studying the powder diffraction method and its applications. In the chapter 4 it is explained how the intensities of the beams diffracted are determined by the atoms positions inside of the elemental cell of the crystal. The properties of the crystalline samples of anatase and rutile are described in the chapter 5. The results of this last analysis are the information which will be processed by means of the auxiliary software: Diffrac AT, Axum and Peakfit as well as the TAFOR and CUANTI software describing this part with more detail in the chapters 6 and 7 where it is mentioned step by step the function of each software until to reach the quantification of crystalline phases, objective of this work. Finally, in the chapter 8 there are a results analysis and conclusions. The contribution of this work is for those learned institutions of limited resources which can tackle in this way the characterization of materials. (Author)

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

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

  14. Probing Local Mineralogy in 3D with Dual Energy X-Ray Microscopy

    Gelb, J.; Yun, S.; Doerr, D.; Hunter, L.; Johnson, B.; Merkle, A.; Fahey, K.

    2013-12-01

    In recent years, 3D imaging of rock microstructures has become routine practice for determining pore-scale properties in the geosciences. X-Ray imaging techniques, such as X-Ray Microscopy (XRM), have demonstrated several unique capabilities: namely, the ability to characterize the same sample across a range of length scales and REVs (from millimeters to nanometers), and to perform these characterizations on the same sample over a range of times/treatments (e.g., to observe fluid transporting through the pore networks in a flow cell). While the XRM technique is a popular choice for structural (i.e., pore) characterization, historically it has provided little mineralogical information. This means that resulting simulations are either based on pore structure alone, or rely on correlative chemical mapping techniques for compositionally-sensitive models. Recent advancements in XRM techniques are now enabling compositional sensitivity for a variety of geological sample types. By collecting high-resolution 3D tomography data sets at two different source settings (energies), results may be mixed together to enhance the appearance (contrast) of specific materials. This approach is proving beneficial, for example, to mining applications to locate and identify precious metals, as well as for oil & gas applications to map local hydrophobicity. Here, we will introduce the technique of dual energy X-Ray microscopy, showing how it extends the capabilities of traditional XRM techniques, affording the same high resolution structural information while adding 3D compositional data. Application examples will be shown to illustrate its effectiveness at both the single to sub-micron length scale for mining applications as well as at the 150 nm length scale for shale rock analysis.

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

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

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

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

  17. X-Ray Diffraction and X-Ray Fluorescent Analyses of Prehistoric Pottery Shards from Ulu Kelantan

    Zuliskandar Ramli; Nik H.S.N. Abdul Rahman; Adnan Jusoh; Yunus Sauman

    2011-01-01

    Problem statement: X-Ray Diffraction (XRD) and X-Ray Fluorescent (XRF) were used in order to obtain mineralogical and elemental composition of seven pottery shards that have been unearthed during the excavation at Peraling Cave and Cha Cave in Ulu Kelantan, Malaysia. Approach: Peraling Cave and Cha Cave were prehistoric sites dating from 10, 000 BC which were inhabited by Hoabinhian people and then continuously used by people of Neolithic culture around 3000 BC. Results: Mineralogical and ele...

  18. The first X-ray diffraction measurements on Mars

    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

  19. [Diffraction gratings used in x-ray spectroscopy]: Final report

    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 cm2. The achromatic holography, on the other hand, should be capable of exposing areas well in excess of 1 cm2 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 μm. 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

  20. A 3D kinematics measurement of knee joint using X-ray projection images

    Most of previous studies about joint kinematic analysis using X-ray image needed totally clear outline bones. However, to obtain the clear outline is not easy in clinical because X-ray image of knee often overlaps with bones. In this study, the method of kinetic analysis that uses the outline, which was not totally clear, was proposed. In order to achieve the aim, P type Fourier Descriptor that can be used in an open curve was applied. And, the library database was preliminary selected using feature vectors which were based on shape feature, initial point and terminal point of the outline. After an outline of the object was divided in three parts, template pattern matching was performed. In results, the standard deviation of errors of patella were θx=1.00±0.84 deg, θy=0.55±0.65 deg and θz=0.62±0.12 deg. As to femur, tibia and patella, a part of divided outlines influenced the accuracy of our proposal method. This result shows that, even if all outline of bone is not clear on X-ray image, 3D kinematic analysis can be carried out. (author)

  1. 3D numerical model of the Omega Nebula (M17): simulated thermal X-ray emission

    Reyes-Iturbide, J; Rosado, M; Rodríguez-Gónzalez, A; González, R F; Esquivel, A

    2009-01-01

    We present 3D hydrodynamical simulations of the superbubble M17, also known as the Omega nebula, carried out with the adaptive grid code yguazu'-a, which includes radiative cooling. The superbubble is modelled considering the winds of 11 individual stars from the open cluster inside the nebula (NGC 6618), for which there are estimates of the mass loss rates and terminal velocities based on their spectral types. These stars are located inside a dense interstellar medium, and they are bounded by two dense molecular clouds. We carried out three numerical models of this scenario, considering different line of sight positions of the stars (the position in the plane of the sky is known, thus fixed). Synthetic thermal X-ray emission maps are calculated from the numerical models and compared with ROSAT observations of this astrophysical object. Our models reproduce successfully both the observed X-ray morphology and the total X-ray luminosity, without taking into account thermal conduction effects.

  2. Understanding Plasticity and Fracture in Aluminum Alloys and their Composites by 3D X-ray Synchrotron Tomography and Microdiffraction

    Hruby, Peter

    differential-aperture X-ray structural microscopy (DAXM), from which peak-broadening characteristics were quantified. Plasticity, as determined by the broadening of diffracted peaks, was mapped in 3D. Two-dimensional (2D) maps of plasticity were directly compared to the corresponding tomography slices. A 3D representation of the plastic zone surrounding the fatigue crack was generated by superimposing the mapped plasticity on the 3D crack profile.

  3. Development of confocal 3D X-ray fluorescence instrument and its applications to micro depth profiling

    We have developed a confocal micro X-ray fluorescence instrument. Two independent X-ray tubes of Mo and Cr targets were installed to this instrument. Two polycapillary full X-ray lenses were attached to two X-ray tubes, and a polycapillary half X-ray lens was also attached to the X-ray detector (silicon drift detector, SDD). Finally, three focus spots of three lenses were adjusted at a common position. By using this confocal micro X-ray fluorescence instrument, depth profiling for layered samples were performed. It was found that depth resolution depended on energy of X-ray fluorescence that was measured. In addition, X-ray elemental maps were determined at different depths for an agar sample including metal fragments of Cu, Ti and Au. The elemental maps showed actual distributions of metal fragments in the agar, indicating that the confocal micro X-ray fluorescence is a feasible technique for non-destructive depth analysis and 3D X-ray fluorescence analysis. (author)

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

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

    2010-07-01

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

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

    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.

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

    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

  7. Magnetoelastic effect in holmium studied by X-ray diffraction

    X-ray diffraction measurements have been performed on a single crystal sample of the rare earth metal holmium. The temperature and magnetic field dependence of the c-lattice parameter was studied in detail below the Neel temperature of 132K. Magnetic structural phase transitions were observed as a change in the c-lattice parameter. In addition, lattice modulations induced by the magnetic structure were investigated by observing satellite reflections. A model based on the exchange magnetostriction can explain these magnetostrictive behaviors. The magnetic structures which were used in the analysis were reproduced by the self-consistent mean field calculation. The model has explained the temperature and magnetic field dependence of the c-lattice parameter, as well as the behaviors of the wave number and the amplitude of the lattice modulation. (author)

  8. A new theory for X-ray diffraction

    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

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

    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 μradian. The electron-beam-exposed line-width can be large (5 to 15 μm 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

  10. 3D X-rays application for precision measurement of the cell structure of extruded polystyrene

    Lim, J. Y.; Kim, K. Y.; Shin, H. S.; Yeom, S.; Lee, S. E.

    2015-12-01

    While the thermal performance of existing insulation materials have been determined by blister gases, the thermal performance of future insulation materials will be dependent on the cell size and independent foam content as we use eco-friendly blister gases with a higher thermal conductivity. However, with the current technology we are only able to guess the whole cell size and independent foam content through SEM applied 2D fragmentary scanning but are still far from the level of accurate cell structure data extraction. Under this situation, we utilized X-ray CT scanned 3D images to identify and shape the cell structure and proposed a method of inferring the whole distribution and independent foam content as accurately as possible. According to X-ray CT scanning images and SEM images, the shape was similar but according to tracer applied CT scanning images, the cell size distribution was 380∼400 pm within the range of the general insulation diameter distribution which had the highest reliability. As for extrusion foaming polystyrene, we need additional image processing to identify the independent foam content as its density is too low. So, it is recommended to raise the 3D cell structure completeness of XPS by improving the scanning accuracy.

  11. X-ray diffraction study of glucomannans and their acetates

    Crystalline polymorphs of four glucomannans with a different mannose/glucose ratio from 1.5 to 4.0 and their acetyl derivatives was studied by X-ray diffraction measurements. The glucomannans showed an amorphous or similar crystal structure (Mannan I or Mannan II polymorph) of β-1,4-d-mannan depending on their mannose content, indicating the occurrence of isomorphous replacement of mannose by glucose during glucomannan crystallization. When these glucomannans were annealed, however, Konjac glucomannan (mannose/glucose ratio = 1.6) showed a different powder pattern from both Mannans I and II. The fiber pattern of the annealed Konjac glucomannan indicated that it took an extended two-fold helical structure. Among the acetylated glucomannans, Higanbana glucomannan with a high mannose content (mannose/glucose = 4.0) showed a similar diffraction pattern to that of β-1,4-d-mannan triacetate, indicating that the isomorphous replacement also occurred in the acetyl derivative. However, glucomannan triacetate with a low mannose content (1.5 or 1.6) showed a different crystalline form from that of mannan triacetate. The fiber diffraction pattern of Konjac glucomannan acetate suggested that it took a three-fold helix

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

    Hambach, D; Schneider, G

    2001-01-01

    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 mm sup 2 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.

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

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

    2013-10-01

    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.

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

    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

  15. Three-dimensional coherent X-ray diffraction imaging of a whole, frozen-hydrated cell

    Rodriguez, Jose A.; Xu, Rui; Chen, Chien-Chun; Huang, Zhifeng; Jiang, Huaidong; Raines, Kevin S.; Nam, Daewoong; Chen, Allan L.; Pryor, A J; Wiegart, Lutz; Song, Changyong; Madsen, Anders; Chushkin, Yuriy; Zontone, Federico; Bradley, Peter J.

    2014-01-01

    A structural understanding of whole cells in three dimensions at high spatial resolution remains a significant challenge and, in the case of X-rays, has been limited by radiation damage. By alleviating this limitation, cryogenic coherent diffraction imaging (cryo-CDI) could bridge the important resolution gap between optical and electron microscopy in bio-imaging. Here, we report for the first time 3D cryo-CDI of a whole, frozen-hydrated cell - in this case a Neospora caninum tachyzoite - usi...

  16. TU-F-BRF-04: Registration of 3D Transesophageal Echocardiography and X-Ray Fluoroscopy Using An Inverse Geometry X-Ray System

    Purpose: To develop a method for the fusion of 3D echocardiography and Scanning-Beam Digital X-ray (SBDX) fluoroscopy to assist with catheter device and soft tissue visualization during interventional procedures. Methods: SBDX is a technology for low-dose inverse geometry x-ray fluoroscopy that performs digital tomosynthesis at multiple planes in real time. In this study, transesophageal echocardiography (TEE) images were fused with SBDX images by estimating the 3D position and orientation (the “pose”) of the TEE probe within the x-ray coordinate system and then spatially transforming the TEE image data to match this pose. An initial pose estimate was obtained through tomosynthesis-based 3D localization of points along the probe perimeter. Position and angle estimates were then iteratively refined by comparing simulated projections of a 3D probe model against SBDX x-ray images. Algorithm performance was quantified by imaging a TEE probe in different known orientations and locations within the x-ray field (0-30 degree tilt angle, up to 50 mm translation). Fused 3D TEE/SBDX imaging was demonstrated by imaging a tissue-mimicking polyvinyl alcohol cylindrical cavity as a catheter was navigated along the cavity axis. Results: Detected changes in probe tilt angle agreed with the known changes to within 1.2 degrees. For a 50 mm translation along the source-detector axis, the detected translation was 50.3 mm. Errors for in-plane translations ranged from 0.1 to 0.9 mm. In a fused 3D TEE/SBDX display, the catheter device was well visualized and coincident with the device shadow in the TEE images. The TEE images portrayed phantom boundaries that were not evident under x-ray. Conclusion: Registration of soft tissue anatomy derived from TEE imaging and device imaging from SBDX x-ray fluoroscopy is feasible. The simultaneous 3D visualization of these two modalities may be useful in interventional procedures involving the navigation of devices to soft tissue anatomy

  17. TU-F-BRF-04: Registration of 3D Transesophageal Echocardiography and X-Ray Fluoroscopy Using An Inverse Geometry X-Ray System

    Speidel, M; Hatt, C; Tomkowiak, M; Raval, A [University of Wisconsin, Madison, WI (United States); Funk, T [Triple Ring Technologies, Inc., Newark, CA (United States)

    2014-06-15

    Purpose: To develop a method for the fusion of 3D echocardiography and Scanning-Beam Digital X-ray (SBDX) fluoroscopy to assist with catheter device and soft tissue visualization during interventional procedures. Methods: SBDX is a technology for low-dose inverse geometry x-ray fluoroscopy that performs digital tomosynthesis at multiple planes in real time. In this study, transesophageal echocardiography (TEE) images were fused with SBDX images by estimating the 3D position and orientation (the “pose”) of the TEE probe within the x-ray coordinate system and then spatially transforming the TEE image data to match this pose. An initial pose estimate was obtained through tomosynthesis-based 3D localization of points along the probe perimeter. Position and angle estimates were then iteratively refined by comparing simulated projections of a 3D probe model against SBDX x-ray images. Algorithm performance was quantified by imaging a TEE probe in different known orientations and locations within the x-ray field (0-30 degree tilt angle, up to 50 mm translation). Fused 3D TEE/SBDX imaging was demonstrated by imaging a tissue-mimicking polyvinyl alcohol cylindrical cavity as a catheter was navigated along the cavity axis. Results: Detected changes in probe tilt angle agreed with the known changes to within 1.2 degrees. For a 50 mm translation along the source-detector axis, the detected translation was 50.3 mm. Errors for in-plane translations ranged from 0.1 to 0.9 mm. In a fused 3D TEE/SBDX display, the catheter device was well visualized and coincident with the device shadow in the TEE images. The TEE images portrayed phantom boundaries that were not evident under x-ray. Conclusion: Registration of soft tissue anatomy derived from TEE imaging and device imaging from SBDX x-ray fluoroscopy is feasible. The simultaneous 3D visualization of these two modalities may be useful in interventional procedures involving the navigation of devices to soft tissue anatomy.

  18. Ultrafast time-resolved X-ray diffraction using an optimized laser-plasma based X-ray source

    Femtosecond X-ray pulses are invaluable tools to investigate the structural dynamics triggered by a femtosecond laser pulse. These ultrashort X-ray pulses can be provided by lab-sized laser-produced plasma X-ray sources. This thesis is dedicated to optimizing the X-ray emission from the X-ray source at the University of Duisburg-Essen and using this source to investigate ultrafast structural dynamics in laser excited materials. For these purposes, detailed investigations on how the laser intensities, target thicknesses, angles of incidence and different pre-pulse/pre-plasma conditions affecting the emission of Kα-photons from Cu and Ti targets were performed. The outcomes from these studies are applied to optimize the X-ray production of the existing X-ray source for time resolved X-ray diffraction (TRXD) experiments. In the mean time, in order to improve the measurement sensitivity/accuracy, and automatize and speed up the experimental procedures, several other improvements have been implemented in the experimental setup for TRXD experiments. These improvements of the setup are essential to achieve the results of the three TRXD experiments discussed in this thesis. In the first experiment, Debye-Waller effect in a thin laser-excited Au film was observed. The drop of measured diffraction signal with a decay time constant of 4.3±1 ps was measured for high excitation fluences. This result is in good agreement with previous experimental results as well as the Two-Temperature Model (TTM) calculations at high fluences. The second experiment extends the studies of coherent optical phonons in laser-excited Bi to a higher excitation fluence range that has not been investigated previously. Large amplitude coherent atomic motion and a complete softening of the A1g phonon mode were observed. These observations represents conclusive experimental evidence that the Peierls distortion, which defines the equilibrium structure of Bi, vanishes and the material is transformed into

  19. An autonomous CZT module for X-ray diffraction imaging

    We present the development of a CZT-based detection module dedicated to X-ray diffraction imaging. This kind of application requires a good energy and spatial resolution in order to resolve Bragg peaks. In a first part, we present the detector configuration used and dimensioning constraints. As the input energy range is comprised between 20 and 150 keV, we use 5 mm thick high resistivity CZT crystals. The 660 mm2 detection area is segmented on both sides into 192 anodes and 12 cathodes. Signals from both sides are read jointly in order to perform multi parametric event corrections (depth of interaction, charge sharing, induction sharing). In order to be integrated easily inside an X-ray imaging system, the system has been conceived to be completely autonomous: it is powered by a single 12 V supply and is interfaced with the external system by Ethernet for communication and RS485 for synchronization. In a second part, we describe the system readout architecture and then the implementation of the data processing. An FPGA circuit embeds a digital processing chain that carries out readout ASIC interfacing and advanced multi parametric data corrections. Gain, offset but also depth of interaction and charge sharing are corrected on the flow. Incoming events from different channels are clustered together by comparing their location and time of occurrence. The FPGA also embeds a processor running an operating system that controls the system, carries out all calibrations, automated tests and acquisitions. Eventually, we show the results obtained and demonstrate the relative influence of depth of interaction and charge sharing. Homogeneity of detector behavior is also discussed and the reproducibility of the performance between modules is presented. The average energy resolution at 25 C is 2.4 % FWHM at 122 keV and 3.8 % FWHM at 60 keV and the average efficiency is 73 %. (authors)

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

    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 n...

  1. Tomography of a Cryo-immobilized Yeast Cell Using Ptychographic Coherent X-Ray Diffractive Imaging

    Giewekemeyer, Klaus; Hackenberger, Claudia; Aquila, Andrew; Wilke, R. N.; Groves, Matthew; Jordanova, R.; Lamzin, V. S.; Borchers, G.; Saksl, K.; Zozulya, A.V.; Sprung, M.; Adrian P. Mancuso

    2015-01-01

    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 ...

  2. Multi-contrast 3D X-ray imaging of porous and composite materials

    Grating-based X-ray computed tomography allows for simultaneous and nondestructive determination of the full X-ray complex index of refraction and the scattering coefficient distribution inside an object in three dimensions. Its multi-contrast capabilities combined with a high resolution of a few micrometers make it a suitable tool for assessing multiple phases inside porous and composite materials such as concrete. Here, we present quantitative results of a proof-of-principle experiment performed on a concrete sample. Thanks to the complementarity of the contrast channels, more concrete phases could be distinguished than in conventional attenuation-based imaging. The phase-contrast reconstruction shows high contrast between the hardened cement paste and the aggregates and thus allows easy 3D segmentation. Thanks to the dark-field image, micro-cracks inside the coarse aggregates are visible. We believe that these results are extremely interesting in the field of porous and composite materials studies because of unique information provided by grating interferometry in a non-destructive way

  3. X-ray color imaging with 3D sensitive voxel detector

    X-ray imaging is today widely used in a broad range of applications. Nevertheless some limitations are represented by the inability to distinguish between a thick layer of low Z material and a thin layer of high Z material, and by the beam hardening, where the incident X-ray spectrum is modified as the beam traverses the sample. Such effects cause problems in many applications (e.g. CT reconstruction) generating artifacts and worsening the spatial resolution. This work presents a new technique allowing spectral sensitivity using a new 3D voxel detector based on the Timepix pixel detector. The device is designed as a layered stack of several Timepix sensors. The readout chip is thinned down to reduce the amount of insensitive absorbing material. Every single layers in the stack act as a filter, i.e. each stack layer visualizes a different part of the spectrum attenuated by the object giving further information about the object composition. The comparison of attenuation levels observed in different detector layers can be used to estimate the extent of the beam hardening effect in the imaged object and thus point out differences in the material composition.

  4. Multi-contrast 3D X-ray imaging of porous and composite materials

    Sarapata, Adrian; Herzen, Julia [Lehrstuhl für Biomedizinische Physik, Physik-Department and Institut für Medizintechnik, Technische Universität München, 85748 Garching (Germany); Ruiz-Yaniz, Maite [Lehrstuhl für Biomedizinische Physik, Physik-Department and Institut für Medizintechnik, Technische Universität München, 85748 Garching (Germany); European Synchrotron Radiation Facility, 38000 Grenoble (France); Zanette, Irene [Lehrstuhl für Biomedizinische Physik, Physik-Department and Institut für Medizintechnik, Technische Universität München, 85748 Garching (Germany); Diamond Light Source, Harwell Science and Innovation Campus, Didcot OX11 0QX (United Kingdom); Rack, Alexander [European Synchrotron Radiation Facility, 38000 Grenoble (France); Pfeiffer, Franz [Lehrstuhl für Biomedizinische Physik, Physik-Department and Institut für Medizintechnik, Technische Universität München, 85748 Garching (Germany); Institut für Diagnostische und Interventionelle Radiologie, Klinikum rechts der Isar, Technische Universität München, 81675 München (Germany)

    2015-04-13

    Grating-based X-ray computed tomography allows for simultaneous and nondestructive determination of the full X-ray complex index of refraction and the scattering coefficient distribution inside an object in three dimensions. Its multi-contrast capabilities combined with a high resolution of a few micrometers make it a suitable tool for assessing multiple phases inside porous and composite materials such as concrete. Here, we present quantitative results of a proof-of-principle experiment performed on a concrete sample. Thanks to the complementarity of the contrast channels, more concrete phases could be distinguished than in conventional attenuation-based imaging. The phase-contrast reconstruction shows high contrast between the hardened cement paste and the aggregates and thus allows easy 3D segmentation. Thanks to the dark-field image, micro-cracks inside the coarse aggregates are visible. We believe that these results are extremely interesting in the field of porous and composite materials studies because of unique information provided by grating interferometry in a non-destructive way.

  5. Registration of 2D x-ray images to 3D MRI by generating pseudo-CT data

    van der Bom, M. J.; Pluim, J. P. W.; Gounis, M. J.; van de Kraats, E. B.; Sprinkhuizen, S. M.; Timmer, J.; Homan, R.; Bartels, L. W.

    2011-02-01

    Spatial and soft tissue information provided by magnetic resonance imaging can be very valuable during image-guided procedures, where usually only real-time two-dimensional (2D) x-ray images are available. Registration of 2D x-ray images to three-dimensional (3D) magnetic resonance imaging (MRI) data, acquired prior to the procedure, can provide optimal information to guide the procedure. However, registering x-ray images to MRI data is not a trivial task because of their fundamental difference in tissue contrast. This paper presents a technique that generates pseudo-computed tomography (CT) data from multi-spectral MRI acquisitions which is sufficiently similar to real CT data to enable registration of x-ray to MRI with comparable accuracy as registration of x-ray to CT. The method is based on a k-nearest-neighbors (kNN)-regression strategy which labels voxels of MRI data with CT Hounsfield Units. The regression method uses multi-spectral MRI intensities and intensity gradients as features to discriminate between various tissue types. The efficacy of using pseudo-CT data for registration of x-ray to MRI was tested on ex vivo animal data. 2D-3D registration experiments using CT and pseudo-CT data of multiple subjects were performed with a commonly used 2D-3D registration algorithm. On average, the median target registration error for registration of two x-ray images to MRI data was approximately 1 mm larger than for x-ray to CT registration. The authors have shown that pseudo-CT data generated from multi-spectral MRI facilitate registration of MRI to x-ray images. From the experiments it could be concluded that the accuracy achieved was comparable to that of registering x-ray images to CT data.

  6. X-ray diffraction analysis of residual stress in zirconia dental composites

    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.

  7. Two digital X-ray imaging systems for applications in X-ray diffraction

    Two digital X-ray imaging systems developed at the Rutherford Appleton Laboratory are described:- the Mark I and the Mark II. Both use a bidimensionally sensitive Multiwire proportional counter as the basic X-ray image transducer coupled to a digital microcomputer system. The Mark I system provides the advantages of high speed, high sensitivity digital imaging directly into the computer with the potential for software control of the sample orientation and environment. The Mark II system adds the novel features of signal averaging and multi-frame exposures. (author)

  8. Preliminary Investigation: 2D-3D Registration of MR and X-ray Cardiac Images Using Catheter Constraints

    Truong, Michael V.N.; Aslam, Abdullah; Rinaldi, Christopher Aldo; Razavi, Reza; Penney, Graeme P.; Rhode, Kawal

    2009-01-01

    Cardiac catheterization procedures are routinely guided by X-ray fluoroscopy but suffer from poor soft-tissue contrast and a lack of depth information. These procedures often employ pre-operative magnetic resonance or computed tomography imaging for treatment planning due to their excellent soft-tissue contrast and 3D imaging capabilities. We developed a 2D-3D image registration method to consolidate the advantages of both modalities by overlaying the 3D images onto the X-ray. Our method uses...

  9. X-Ray Nanofocus CT: Visualising Of Internal 3D-Structures With Submicrometer Resolution

    Weinekoetter, Christian

    2008-09-01

    High-resolution X-ray Computed Tomography (CT) allows the visualization and failure analysis of the internal micro structure of objects—even if they have complicated 3D-structures where 2D X-ray microscopy would give unclear information. During the past several years, computed tomography has progressed to higher resolution and quicker reconstruction of the 3D-volume. Most recently it even allows a three-dimensional look into the inside of materials with submicron resolution. With the use of nanofocus® tube technology, nanoCT®-systems are pushing forward into application fields that were exclusive to high cost and rare available synchrotron techniques. The study was performed with the new nanotom, a very compact laboratory system which allows the analysis of samples up to 120 mm in diameter and weighing up to 1 kg with exceptional voxel-resolution down to nanoCT-examinations e.g. of synthetic materials, metals, ceramics, composite materials, mineral and organic samples. There are a few physical effects influencing the CT quality, such as beam-hardening within the sample or ring-artefacts, which can not be completely avoided. To optimize the quality of high resolution 3D volumes, the nanotom® includes a variety of effective software tools to reduce ring-artefacts and correct beam hardenings or drift effects which occurred during data acquisition. The resulting CT volume data set can be displayed in various ways, for example by virtual slicing and sectional views in any direction of the volume. By the fact that this requires only a mouse click, this technique will substitute destructive mechanical slicing and cutting in many applications. The initial CT results obtained with the nanotom® demonstrate that it is now possible to analyze the three-dimensional micro structure of materials and small objects with submicrometer resolution. Any internal difference in material, density or porosity within a sample can be visualized and data like distances can be measured

  10. A magnetic x-ray diffraction investigation of gadolinium selenide

    Costa, M.M.R.; Almeida, M.J.M. de [Departamento de Fisica, Universidade de Coimbra, Coimbra (Portugal); Nuttall, W.J.; Stirling, W.G. [Department of Physics, Keele University, Keele, Staffs (United Kingdom); Tang, C.C. [Daresbury Laboratory, Warrington, Cheshire (United Kingdom); Forsyth, J.B. [Rutherford Appleton Laboratory, Chilton, Oxon (United Kingdom); Cooper, M.J. [Department of Physics, University of Warwick, Coventry (United Kingdom)

    1996-04-01

    A single-crystal synchrotron radiation study of gadolinium selenide has been made in the temperature range 15-100 K. GdSe has the rocksalt structure and becomes antiferromagnetic below a reported Neel temperature of 65 K. At 15 K, magnetic reflections are observed at G+T with modulation wavevector T={l_brace}1/2:1/2:1/2{r_brace} propagating from reciprocal lattice point G. This is achieved by exploiting the resonant enhancement in the vicinity of the Gd L{sub II} and L{sub III} edges. Similar enhancements are observed at the two edges, with the maximum effect occurring approximately 3 eV above the absorption edge. The temperature dependence of the intensity of the magnetic reflections indicates a Neel temperature of 63(1) K. These measurements, together with high-resolution studies of the fundamental reflections (T=0), contribute further evidence of magnetic or structural changes in the sample at 37(1) K. Our observations are discussed and compared with previous x-ray diffraction and magnetic susceptibility measurements. (author)

  11. Federated repositories of X-ray diffraction images.

    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

  12. X-ray diffraction analysis of mudstone from nw sudan

    This study deals with the theoretical and experimental aspects of the x-ray diffraction technique (XRD). The XRD technique is used to investigate fine structure of matter, and it is most efficient method for the determination of the mineralogical composition of rocks. The XRD technique is used also to investigate the clay mineralogical of mud-stones of the Nubian sandstones of north western Sudan. The XRD results revealed that the mud-stone samples are composed, in decreasing abundance's of kaolinite, smectite, chlorite and illite. Non-clay minerals reported include quartz, feldspars and geothite. Kaolinite dominates in most of samples with percentages ranging between 78-96%. Smectite comes second in abundance and ranges between 10-24%, followed by chlorite and illite which showed the lowest abundance's. The dominance of kaolinite over smectite indicates that intense chemical weathering and leaching occurred under warm humid climate interrupted by dry periods. Most probably these clay minerals were produced by inheritance and partly by neo formation. The variation of the chemical composition of these mud stones is due basically to differences in clay mineralogy which was controlled by source rock geology, weathering physicochemical behavior of elements, local environment and climatic condition in the past. (Author)

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

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

  14. X-ray diffraction study of synthetic tetraborates and hexaborates

    The results of the X-ray diffraction of the tetraborates (NH3CH2CH2NH3)(B4O5(OH)4), (NH4)(Co(NH3)5H2O)(B4O5(OH)4)2x5H2O and of the hexaborates Ni(H2O)4(B6O)(OH)6xH2O (triclinic and monoclinic modification). (NH4)2{Co(H2O)2(B6O7(OH)6)2}x2H2O, (Ni(H2O)6){Ni(B6O7(OH)3(OCH3)3)2}, Co(H2O)3(B6O7(OH)6)x1.5C2H5OH and Ni(H2O)3(B6O7(OH)6)xC2H5OH have been reviewed. The crystal solvates isostructural to the latter compound - nickel hexaborates containing propyl and allyl alcohols, acetone and methyl ethyl ketone have been studied

  15. Investigation of kidney stones by X-ray diffraction method

    Muakthong, D.

    2005-01-01

    Full Text Available An investigation of 39 male kidney stone samples and 11 female kidney stone samples obtained from Songklanakarind Hospital, Hat Yai, Songkhla was carried out. Most samples were obtained from patients ages over 40 years. By means of X-ray diffraction (XRD, kidney stones can be classified according to their structure and composition into 3 groups is 1. uric acid (C5H4N4O3 and ammonium acid urate (C5H7N5O3 2. oxalates; whewelite (C2CaO4!H2O CaC2O4!H2O and weddellite (C2CaO4!2H2O 3. phosphates; struvite (NH4MgPO4!6H2O and calcium phosphate hydrate (Ca3(PO42!xH2O. External and internal environments such as occupation, dietary habits, lack of water-drinking etc. are the major factors for kidney stone formation. Results from this study are very useful for the patients to prevent recrystallization of kidney stones by avoiding some elements or some organic compounds which are main components of kidney stones formed in the human urinary system.

  16. Neutron and x-ray diffraction studies in cement

    Full text: Phase quantification of cement is difficult due to the complexity of phases, and cement composition is complicated by the polymorphic modifications of these phases. Only three of the seven polymorphs of the main component of cement, tricalcium silicate, have their structures fully determined, although more polymorphs are likely to be present There has been an increase in the use of Rietveld refinement for the analysis of cement in recent years, and an advantage of the method is the ability to define the tricalcium silicate form. It is usual to include a polymorph of tricalcium silicate in each of the three crystal systems encountered when beginning a refinement, and then exclude those not found. Care must be taken not to allow one crystal system to alter itself to compensate for another. Using synchrotron x-ray diffraction data, refinement of some atomic positions in a tricalcium silicate form resulted in a 24.5% improvement in the fits of the phase. An investigation using neutron data also showed significant improvement in the rb values for two polymorph of tricalcium silicate in a clinker sample, and also showed slight deviation in the phase quantification results obtained

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

    Dae-Hwan Park

    2016-03-01

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

  18. Local ISM 3D Distribution and Soft X-ray Background Inferences for Nearby Hot Gas

    Puspitarini, L.; Lallement, R.; Snowden, Steven L.; Vergely, J.-L.; Snowden, S.

    2014-01-01

    Three-dimensional (3D) interstellar medium (ISM) maps can be used to locate not only interstellar (IS) clouds, but also IS bubbles between the clouds that are blown by stellar winds and supernovae, and are filled by hot gas. To demonstrate this, and to derive a clearer picture of the local ISM, we compare our recent 3D IS dust distribution maps to the ROSAT diffuse Xray background maps after removal of heliospheric emission. In the Galactic plane, there is a good correspondence between the locations and extents of the mapped nearby cavities and the soft (0.25 keV) background emission distribution, showing that most of these nearby cavities contribute to this soft X-ray emission. Assuming a constant dust to gas ratio and homogeneous 106 K hot gas filling the cavities, we modeled in a simple way the 0.25 keV surface brightness along the Galactic plane as seen from the Sun, taking into account the absorption by the mapped clouds. The data-model comparison favors the existence of hot gas in the solar neighborhood, the so-called Local Bubble (LB). The inferred mean pressure in the local cavities is found to be approx.9,400/cu cm K, in agreement with previous studies, providing a validation test for the method. On the other hand, the model overestimates the emission from the huge cavities located in the third quadrant. Using CaII absorption data, we show that the dust to CaII ratio is very small in those regions, implying the presence of a large quantity of lower temperature (non-X-ray emitting) ionized gas and as a consequence a reduction of the volume filled by hot gas, explaining at least part of the discrepancy. In the meridian plane, the two main brightness enhancements coincide well with the LB's most elongated parts and chimneys connecting the LB to the halo, but no particular nearby cavity is found towards the enhancement in the direction of the bright North Polar Spur (NPS) at high latitude. We searched in the 3D maps for the source regions of the higher energy

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

    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 ...

  20. 3-d chemical imaging using angle-scan nanotomography in a soft X-ray scanning transmission X-ray microscope

    Three-dimensional chemical mapping using angle scan nanotomography in a soft X-ray scanning transmission X-ray microscope (STXM) has been used to investigate the spatial distributions of a low density polyacrylate polyelectrolyte ionomer inside submicron sized polystyrene microspheres. Acquisition of tomograms at multiple photon energies provides true, quantifiable 3-d chemical sensitivity. Both pre-O 1s and C 1s results are shown. The study reveals aspects of the 3-d distribution of the polyelectrolyte that were inferred indirectly or had not been known prior to this study. The potential and challenges for extension of the technique to studies of other polymeric and to biological systems is discussed. (orig.)

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

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

    2014-01-01

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

  2. Complementing high-throughput X-ray powder diffraction data with quantum-chemical calculations

    Naelapaa, Kaisa; van de Streek, Jacco; Rantanen, Jukka;

    2012-01-01

    single crystals or bulk samples of sufficient quantity to carry out high-quality X-ray diffraction measurements. This process could be made more efficient by a robust procedure for crystal structure determination directly from high-throughput X-ray powder diffraction (XRPD) data. Quantum...

  3. Transmission x-ray diffraction of undisturbed soil microfabrics obtained by microdrilling in thin sections

    Denaix, L.; Oort, van F.; Pernes, M.; Jongmans, A.G.

    1999-01-01

    Clay mineralogical studies by X-ray diffraction performed on extracted <2-μm fractions do not always represent all clay mineral constituents present in the soil. In this work, transmission X-ray diffraction (TXRD) was applied to undisturbed microsamples of optically homogeneous mineral soil fabrics

  4. Diffuse X-ray diffraction by a crystal of an aging alloy

    The theory of the diffusive X-ray diffraction is considered on the generalized model of the aging alloy structure. The formula for calculating the distribution of the X-ray diffusive diffraction intensity for such model is deduced. This formula allows to obtain the theoretical distribution of the diffusive scattering intensity for different specific model

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

    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)

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

    Crouse, David T.

    2007-01-01

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

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

    Ludwig, Wolfgang; King, A.; Herbig, M.; Reischig, P.; Marrow, J.; Babout, L.; Lauridsen, Erik Mejdal; Proudhon, H.; Buffiere, J.Y.

    2010-01-01

    The combination of synchrotron radiation x-ray imaging and diffraction techniques offers new possibilities for in-situ observation of deformation and damage mechanisms in the bulk of polycrystalline materials. Minute changes in electron density (i.e., cracks, porosities) can be detected using......-ray diffraction contrast tomography provides access to the 3-D shape, orientation, and elastic strain state of the individual grains from polycrystalline sample volumes containing up to thousand grains. Combining both imaging modalities, one obtains a comprehensive description of the materials microstructure at...... the micrometer length scale. Repeated observation during (interrupted) mechanical tests provide unprecedented insight into crystallographic and grain microstructure related aspects of polycrystalline deformation and degradation mechanisms....

  8. X-RAY DIFFRACTION STUDY OF A PANCHAVAKTRA RAS

    B. Srinivasulu*, P. Bhadra Dev, P.H.C. Murthy

    2012-06-01

    Full Text Available Analytical monitoring of Pharmaceutical products is necessary to ensure its safety and efficacy throughout all phases of the drug. A systematic approach should be adapted to the presentation and evaluation of stable information, which should include, as necessary, physical, chemical, biological and microbiological test characteristics. Indian System of Medicine (ISM frequently uses metal/mineral drugs. It is mandatory to standardize the preparatory procedures. For the Pharmaceutical standardization, three batches of the Panchavaktra ras were prepared and analytical study of final product carried out. Panchavaktra ras consist equal parts of Parada (Mercury, Gandhaka (Sulphur, Tankana (Borax Pippali (Piper longum L. and Marica (Piper nigrum L., and Mardhana (Grinding was done carefully with sufficient quantity of juice of Datura metel leaves for 24 hours and a final product was obtained in the form of Vati (tablet form. It is one of the formulations mentioned in Amavata (Rheumatoid Arthritis disease. The final products were subjected to Powder X-Ray Diffraction (XRD studies and values of XRD peaks of particular Panchavaktra ras were observed. This study revealed that high peaks of HgS (Metacinnabar, free S (Sulfur, Chabazite (Ca- exchanged, dehydrated Ca (structure- Rhombohedral in the final products. The structural and chemical characterization of the HgS (Metacinnabar found as cubic, free S (Sulphur as Orthorhombic in all the samples. The 50% strongest peaks of HgS were present at 2-Theta scale between 26-31, 43-44, 51-55, 70-72 degrees. This paper points out the importance of XRD, as a standard tool for further studies and research of Herbo-mineral formulations.

  9. Moving-Article X-Ray Imaging System and Method for 3-D Image Generation

    Fernandez, Kenneth R. (Inventor)

    2012-01-01

    An x-ray imaging system and method for a moving article are provided for an article moved along a linear direction of travel while the article is exposed to non-overlapping x-ray beams. A plurality of parallel linear sensor arrays are disposed in the x-ray beams after they pass through the article. More specifically, a first half of the plurality are disposed in a first of the x-ray beams while a second half of the plurality are disposed in a second of the x-ray beams. Each of the parallel linear sensor arrays is oriented perpendicular to the linear direction of travel. Each of the parallel linear sensor arrays in the first half is matched to a corresponding one of the parallel linear sensor arrays in the second half in terms of an angular position in the first of the x-ray beams and the second of the x-ray beams, respectively.

  10. Qualitative analysis of powder x-ray diffraction data

    methods of considering significant lines such as with the Hanawalt, Fink and alphabetical index; computer based search-match based on FOM and the more recent graphically based full pattern methods of phase identification. No single approach is foolproof. a range of techniques is recommended if a high level of success is required. Copyright (1999) Australian X-ray Analytical Association Inc

  11. 3D X-Ray imaging of bone tissue from micro to nano scale and associated inverse problems

    Peyrin, F.; Toma, A; Sixou, B.; Denis, L.; Wang, L.(Universität Bochum, Institut für Experimentalphysik, Bochum, 44780, Germany); WEBER,L; Langer, M. (Marco); Cloetens, P.

    2015-01-01

    Imaging bone tissue from the organ to the cellular level is a major goal in bone research to understand, diagnose and predict bone fragility associated to bone disease such as osteoporosis. In this presentation, we show that X-ray CT is particularly well adapted to image bone in 3D up to the nanometer scale. After recalling the principles of 3D CT, we describe advances in bone CT imaging and the needs in associated inverse problems. Clinical X-ray CT is daily used to image skeletal tissue at ...

  12. 3D X-ray CT and diffusion measurements to assess tortuosity and constrictivity in a sedimentary rock

    Takahashi, Hiroaki; Seida, Yoshimi; Yui, Mikazu

    2015-01-01

    A high-resolution, three-dimensional (3D) image of the interior of the sedimentary rock was obtained by means of nano-focus X-ray computer tomography (X-ray CT). Using computational methods to analyze the 3D microstructure of the rock, we presented the tortuosity and geometrical constrictivity. We also presented results on the tritiated water (HTO) diffusion tests and a mercury intrusion porosimetry (MIP) test performed on the rock. We have compared these results to understand the dominant...

  13. 3D RECONSTRUCTION FROM MULTI-VIEW MEDICAL X-RAY IMAGES – REVIEW AND EVALUATION OF EXISTING METHODS

    S. Hosseinian

    2015-12-01

    Full Text Available The 3D concept is extremely important in clinical studies of human body. Accurate 3D models of bony structures are currently required in clinical routine for diagnosis, patient follow-up, surgical planning, computer assisted surgery and biomechanical applications. However, 3D conventional medical imaging techniques such as computed tomography (CT scan and magnetic resonance imaging (MRI have serious limitations such as using in non-weight-bearing positions, costs and high radiation dose(for CT. Therefore, 3D reconstruction methods from biplanar X-ray images have been taken into consideration as reliable alternative methods in order to achieve accurate 3D models with low dose radiation in weight-bearing positions. Different methods have been offered for 3D reconstruction from X-ray images using photogrammetry which should be assessed. In this paper, after demonstrating the principles of 3D reconstruction from X-ray images, different existing methods of 3D reconstruction of bony structures from radiographs are classified and evaluated with various metrics and their advantages and disadvantages are mentioned. Finally, a comparison has been done on the presented methods with respect to several metrics such as accuracy, reconstruction time and their applications. With regards to the research, each method has several advantages and disadvantages which should be considered for a specific application.

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

    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 ⋅ 0.6H2O

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

    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

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

    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.

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

    Hartung, Steffen; Bucher, Nicolas [TUM CREATE, Singapore 138602 (Singapore); Technical University of Munich, Garching 85748 (Germany); School of Materials Science and Engineering, Nanyang Technological University, Singapore 639798 (Singapore); Bucher, Ramona [TUM CREATE, Singapore 138602 (Singapore); Srinivasan, Madhavi [TUM CREATE, Singapore 138602 (Singapore); School of Materials Science and Engineering, Nanyang Technological University, Singapore 639798 (Singapore)

    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. Non-destructive analysis of micro texture and grain boundary character from X-ray diffraction contrast tomography

    Recent advances in synchrotron based X-ray imaging and diffraction techniques offer interesting new possibilities for mapping 3D grain shapes and crystallographic orientations in different classes of polycrystalline materials. X-ray diffraction contrast tomography (DCT) is a monochromatic beam imaging technique combining the principles of X-ray micro-tomography and three-dimensional X-ray diffraction microscopy (3DXRD). DCT provides simultaneous access to 3D grain shape, crystallographic orientation and attenuation coefficient distribution at the micrometer length scale. The microtexture of the material can be quantified in more detail by post-processing of the volume data provided by DCT. In particular one can determine the local crystallographic habit plane of the grain boundary by analysing the surface normal of the grain boundary with respect to the crystal orientation. The resulting five parameter description of the character of individual grain boundaries could previously be produced only by destructive characterization techniques. Statistical analysis of this kind of data can be expected to provide new insight into various physico-chemical processes, driven by the grain boundary energy (corrosion, coarsening).

  19. Two digital X-ray imaging systems for applications in X-ray diffraction

    Two digital X-ray imaging systems developed at the Rutherford Appleton Laboratory are described: the Mark I and the Mark II. Both use a bidimensionally sensitive multiwire proportional counter (MWPC) as the basic X-ray image transducer coupled, in the case of the Mark I to a Digital LSI 11-23 microcomputer system via CAMAC, and in the case of the Mark II to a Digital LSI 11-73 microcomputer system via custom-built data acquisition hardware mounted directly on the Q-bus of the microcomputer. The Mark I system provides the advantages of high speed, high sensitivity digital imaging directly into the computer with the potential for software control of the sample orientation and environment. The Mark II system adds the novel features of signal averaging and multiframe exposures. The dedicated digital memories have a resolution of 512x512 pixels of 16 bits, matching well to the spatial resolution of the xenon-filled MWPC (0.5 mm fwhm over an aperture of 200 mm x 200 mm). A 512x512x4 bit video graphics system displays the images in grey scales or colour. (orig.)

  20. Sloped irradiation techniques in deep x-ray lithography for 3D shaping of microstructures

    Feiertag, Gregor; Ehrfeld, Wolfgang; Lehr, Heinz; Schmidt, Martin

    1997-07-01

    Deep x-ray lithography (DXRL) makes use of synchrotron radiation (SR) to transfer an absorber pattern from a mask into a thick resist layer. For most applications the direction of the SR beam is perpendicular to the mask and the resist plane. Subsequent replication techniques, e.g. electroforming, moulding or hot embossing, convert the resist relief obtained after development into micromechanical, microfluidic or micro- optical elements made from metals, polymers or ceramic materials. This process sequence is well known as the LIGA technique. The normal shadow printing process is complemented and enhanced by advanced techniques, e.g. by tilting the mask and the resist with respect to the SR beam or aligned multiple exposures to produce step-like structures. In this paper a technology for the fabrication of multidirectional inclined microstructures applying multiple tilted DXRL will be presented. Instead of one exposure with the mask/substrate assembly perpendicular to the SR beam, irradiation is performed several times applying tilt and rotational angles of the mask/substrate assembly relative to the SR beam. A huge variety of 3-D structures can be obtained using this technique. Some possible applications will be discussed.

  1. Measurement of thickness of thin films by the X-ray diffraction method

    X-ray diffraction method can be used to measure the thickness of thin films (coatings). The principle and the experimental details of the x-ray diffraction methods are described. The intensities of the diffracted beams are derived assuming a random orientation of the crystallites in the diffracting medium. Consequently, the expressions are not valid when the sample has preferred orientation. To check the performance of the method, thicknesses of nickel deposits on mild steel plates were determined by the x-ray diffraction method and the results compared with those obtained by the weighing method and metallographic examination. The weighing method which gives an accuracy of +- 0.1 micron is taken as the standard. The x-ray diffraction methods and the metallographic examinations give values within +- 1 micron of the value obtained by the weighing method. (author)

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

    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.

  3. Application of relativistic scattering theory of x rays to diffraction anomalous fine structure in Cu

    Arola, E.; Strange, Paul

    1998-01-01

    We apply our recent first-principles formalism of magnetic scattering of circularly polarized x rays to a single Cu crystal. We demonstrate the ability of our formalism to interpret the crystalline environment related near-edge fine structure features in the resonant x-ray scattering spectra at the Cu K absorption edge. We find good agreement between the computed and measured diffraction anomalous fine structure features of the x-ray scattering spectra.

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

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

    2011-01-01

    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 wi...

  5. Structural Investigations of Nanowires Using X-Ray Diffraction

    Stankevic, Tomas

    Advancements in growth of the nanowire-based devices opened another dimension of possible structures and material combinations, which nd their applications in a wide variety of elds, including everyday life. Characterization of such devices brings its own challenges and here we show that X-rays o...

  6. [X-ray diffraction experiments with condenser matter

    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

  7. X-ray powder diffraction in forensic practice

    Kotrlý, M.; Bezdička, Petr

    2006-01-01

    Roč. 13, č. 3 (2006), s. 153-155. ISSN 1210-8529 R&D Projects: GA MV RN20052005001 Institutional research plan: CEZ:AV0Z40320502 Keywords : X-ray powder microdiffraction * pigments * forensic practice Subject RIV: CA - Inorganic Chemistry

  8. Direct assessment of 3D foot bone kinematics using biplanar X-ray fluoroscopy and an automatic model registration method

    Ito, Kohta; Hosoda, Koh; Shimizu, Masahiro; Ikemoto, Shuhei; Kume, Shinnosuke; Nagura, Takeo; Imanishi, Nobuaki; Aiso, Sadakazu; Jinzaki, Masahiro; Ogihara, Naomichi

    2015-01-01

    Background Quantifying detailed 3-dimensional (3D) kinematics of the foot in contact with the ground during locomotion is crucial for understanding the biomechanical functions of the complex musculoskeletal structure of the foot. Biplanar X-ray fluoroscopic systems and model-based registration techniques have recently been employed to capture and visualise 3D foot bone movements in vivo, but such techniques have generally been performed manually. In the present study, we developed an automati...

  9. 3D Nanoscale Chemical Imaging of the Distribution of Aluminum Coordination Environments in Zeolites with Soft X-Ray Microscopy

    Aramburo, Luis R.; Liu, Yijin; Tyliszczak, Tolek; de Groot, Frank M. F.; Andrews, Joy C.; Weckhuysen, Bert M.

    2013-01-01

    Here, we present the first nanoscale chemical imaging study revealing the spatial distribution of the amount and coordination environment of aluminum in zeolite materials with 3D scanning transmission X-ray microscopy (STXM). For this purpose, we have focused on two showcase samples involving the in

  10. Computed X-ray powder diffraction patterns for ultrasmall zeolite crystals

    Theoretical X-ray diffraction patterns have been calculated for powders of very small faujasite (FAU) and ZSM-5 (MFI) crystallites. These calculated patterns give the first realistic picture of the expected appearance of X-ray powder diffraction patterns of ultrasmall crystals of these well known commercial zeolites. The X-ray patterns were calculated using SKIP -small-crystal interference program - a program originally written to assist in the interpretation of X-ray diffraction patterns of synthetic zeolites and layered materials. The results are somewhat surprising in that they suggest that the crystallite size of faujasite must fall to below 4-5 unit cells before the resulting pattern diverges significantly from the asymptotic pattern. In contrast, the calculated X-ray pattern of ten-unit-cell ZSM-5 crystallites is scarcely recognizable. (orig.)

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

    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.

  12. Review - X-ray diffraction measurements in high magnetic fields and at high temperatures

    Yoshifuru Mitsui, Keiichi Koyama and Kazuo Watanabe

    2009-01-01

    Full Text Available A system was developed measuring x-ray powder diffraction in high magnetic fields up to 5 T and at temperatures from 283 to 473 K. The stability of the temperature is within 1 K over 6 h. In order to examine the ability of the system, the high-field x-ray diffraction measurements were carried out for Si and a Ni-based ferromagnetic shape-memory alloy. The results show that the x-ray powder diffraction measurements in high magnetic fields and at high temperatures are useful for materials research.

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

    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

    2009-01-01

    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 demonstr...

  14. Characterization of diffraction gratings by use of a tabletop soft-x-ray laser

    We have demonstrated the use of a high-repetition-rate 46.9-mm tabletop laser to characterize diffraction gratings designed for grazing-incidence operation in the soft-x-ray spectral region. The efficiencies for various diffraction orders were measured as a function of angle of incidence and compared with the results of model simulations. This measurement technique provides benchmarks with which to improve electromagnetic codes used in the design of soft-x-ray diffraction gratings. The results illustrate the potential of compact tabletop soft-x-ray lasers for use as a new tool for characterization of short-wavelength optics at the manufacturer's site

  15. Microprocessor-based system for automatic X-ray diffraction and fluorescence

    A data acquisition and processing device appropriate for X-ray analysis and goniometer control was built. The Z-80 based system as well as the whole architeture is described. The advantages and new possibilities of the automated instrument as compared to the traditional ones are listed. The X-ray diffraction and fluorescence techniques can take advantage of the automation. (Author)

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

    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

  17. X-ray Diffraction Study of Single-base Propellant Ageing

    2001-01-01

    Ageing of single-base propellants, extending over a storage period of more than 50 years, was investigated by X-ray diffraction analysis. X-ray degree of crystallinity and interplanar spacing were determined. Analysed was the effect of nitrogen content, degree of substitution (DOS) and diphenylamine (DPA) content on structural changes in propellants.

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

    Henriksen, Niels Engholm; Møller, Klaus Braagaard

    2008-01-01

    We derive the basic theoretical formulation for X-ray diffraction with pulsed fields, using a fully quantized description of light and matter. Relevant time scales are discussed for coherent as well as incoherent X-ray pulses, and we provide expressions to be used for calculation...

  19. The x-ray diffraction pattern and deformation texture of beeswax

    The x-ray diffraction pattern of beeswax shows paraffin-like spacings which have been attributed to monoesters, and long spacings which have been attributed to diesters and hydrocarbons. The d-values and line intensities are given. Optical and x-ray observations of deformed specimens indicate that the molecular axes tend to lie perpendicular to the direction of elongation

  20. Electrochemical discharge of nanocrystalline magnetite: structure analysis using X-ray diffraction and X-ray absorption spectroscopy.

    Menard, Melissa C; Takeuchi, Kenneth J; Marschilok, Amy C; Takeuchi, Esther S

    2013-11-14

    Magnetite (Fe3O4) is an abundant, low cost, environmentally benign material with potential application in batteries. Recently, low temperature coprecipitation methods have enabled preparation of a series of nanocrystalline magnetite samples with a range of crystallite sizes. Electrochemical cells based on Li/Fe3O4 show a linear increase in capacity with decreasing crystallite size at voltages ≥1.2 V where a 2× capacity improvement relative to commercial (26.2 nm) magnetite is observed. In this report, a combination of X-ray powder diffraction (XRD) and X-ray absorption spectroscopy (XAS) is used to measure magnetite structural changes occurring upon electrochemical reduction, with parent Fe3O4 crystallite size as a variable. Notably, XAS provides evidence of metallic iron formation at high levels of electrochemical reduction. PMID:24077019

  1. Fully 3D-Integrated Pixel Detectors for X-Rays

    Deptuch, Grzegorz W. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Gabriella, Carini [SLAC National Accelerator Lab., Menlo Park, CA (United States); Enquist, Paul [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Grybos, Pawel [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Holm, Scott [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Lipton, Ronald [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Maj, Piotr [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Patti, Robert [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Siddons, David Peter [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Szczygiel, Robert [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Yarema, Raymond [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)

    2016-01-01

    The vertically integrated photon imaging chip (VIPIC1) pixel detector is a stack consisting of a 500-μm-thick silicon sensor, a two-tier 34-μm-thick integrated circuit, and a host printed circuit board (PCB). The integrated circuit tiers were bonded using the direct bonding technology with copper, and each tier features 1-μm-diameter through-silicon vias that were used for connections to the sensor on one side, and to the host PCB on the other side. The 80-μm-pixel-pitch sensor was the direct bonding technology with nickel bonded to the integrated circuit. The stack was mounted on the board using Sn–Pb balls placed on a 320-μm pitch, yielding an entirely wire-bond-less structure. The analog front-end features a pulse response peaking at below 250 ns, and the power consumption per pixel is 25 μW. We successful completed the 3-D integration and have reported here. Additionally, all pixels in the matrix of 64 × 64 pixels were responding on well-bonded devices. Correct operation of the sparsified readout, allowing a single 153-ns bunch timing resolution, was confirmed in the tests on a synchrotron beam of 10-keV X-rays. An equivalent noise charge of 36.2 e- rms and a conversion gain of 69.5 μV/e- with 2.6 e- rms and 2.7 μV/e- rms pixel-to-pixel variations, respectively, were measured.

  2. Analysis of a 3D imaging device by reconstruction from cone beam X ray radiographs

    The aim of our study is to analyse the principle of a 3D imaging device which attempts to restore the local density on a cuberill from a set of digital radiographs taken around the object. We have to use a ponctual radiation source to localize the acquisition lines. Therefore the attenuation measurements are modelled by the cone beam X ray transform. In the analysis of the inverse problem, we work out two inversion diagrams which compute the original function, the image of the object, by a sequence of transforms. The theoretical and algorithmical difficulty comes from the fact that, even in the simple case of a circular acquisition trajectory, the cone-shaped geometry prohibits splitting the problem into a superposition of reconstructions in two dimensions. We describe a novel theoretical framework based on the Radon transform. In this new representation space, it becomes possible by a rebinning operation to redistribute the integral values associated to planes from the coordinates system linked to source positions to the spherical coordinates system of the domain. To ensure this shift of space, we have established two formulas, the first approximate but leading to faster processing, related to the Radon transform, the second exact, related to the first derivative of the Radon transform. The inversion of these transforms completes the reconstruction. We state a theorem where we present the hypothesis under which the exact diagram does restore the original function. These are not verified for a circular trajectory, owing to a shadow zone in the Radon domain associated to the planes which intersect the object but not the trajectory. We propose either to restore the missing information or to use an oscillating trajectory

  3. Ultrafast structural dynamics studied by kilohertz time-resolved x-ray diffraction

    郭鑫; 江舟亚; 陈龙; 陈黎明; 辛建国; 陈洁

    2015-01-01

    Ultrashort multi-keV x-ray pulses are generated by electron plasma produced by the irradiation of femtosecond pulses on metals. These sub-picosecond x-ray pulses have extended the field of x-ray spectroscopy into the femtosecond time domain. However, pulse-to-pulse instability and long data acquisition time restrict the application of ultrashort x-ray systems operating at low repetition rates. Here we report on the performance of a femtosecond laser plasma-induced hard x-ray source that operates at 1-kHz repetition rate, and provides a flux of 2.0 × 1010 photons/s of Cu Kα radiation. Using this system for time-resolved x-ray diffraction experiments, we record in real time, the transient processes and structural changes induced by the interaction of 400-nm femtosecond pulse with the surface of a 200-nm thick Au (111) single crystal.

  4. X-Ray Diffraction Determination of Stresses in Thin Films

    Vreeland, T.; Dommann, A.; Tsai, C.-J.; Nicolet, M-A.

    1988-01-01

    This paper presents the methodology employed in the determination of the stress tensor for thin crystalline films using x-ray rocking curves. Use of the same equipment for the determination of the average stress in poly- or non-crystalline thin films attached to a crystalline substrate is also discussed. In this case the lattice curvature of the substrate is determined by measurement of the shift In the Bragg peak with lateral position in the substrate. Strains in single crystal layers may...

  5. 3D Ultrastructural organization of whole Chlamydomonas reinhardtii cells studied by nanoscale soft x-ray tomography.

    Eric Hummel

    Full Text Available The complex architecture of their structural elements and compartments is a hallmark of eukaryotic cells. The creation of high resolution models of whole cells has been limited by the relatively low resolution of conventional light microscopes and the requirement for ultrathin sections in transmission electron microscopy. We used soft x-ray tomography to study the 3D ultrastructural organization of whole cells of the unicellular green alga Chlamydomonas reinhardtii at unprecedented spatial resolution. Intact frozen hydrated cells were imaged using the natural x-ray absorption contrast of the sample without any staining. We applied different fiducial-based and fiducial-less alignment procedures for the 3D reconstructions. The reconstructed 3D volumes of the cells show features down to 30 nm in size. The whole cell tomograms reveal ultrastructural details such as nuclear envelope membranes, thylakoids, basal apparatus, and flagellar microtubule doublets. In addition, the x-ray tomograms provide quantitative data from the cell architecture. Therefore, nanoscale soft x-ray tomography is a new valuable tool for numerous qualitative and quantitative applications in plant cell biology.

  6. Precision measurement of the $3d \\to 2p$ x-ray energy in kaonic $^4$He

    Okada, S; Bhang, H; Cargnelli, M; Chiba, J; Choi, Seonho; Curceanu, C; Fukuda, Y; Hanaki, T; Hayano, R S; Iio, M; Ishikawa, T; Ishimoto, S; Ishiwatari, T; Itahashi, K; Iwai, M; Iwasaki, M; Juhász, B; Kienle, P; Marton, J; Matsuda, Y; Ohnishi, H; Outa, H; Sato, M; Schmid, P; Suzuki, S; Suzuki, T; Tatsuno, H; Tomono, D; Widmann, E; Yamazaki, T; Yim, H; Zmeskal, J

    2007-01-01

    We have measured the Balmer-series x-rays of kaonic $^4$He atoms using novel large-area silicon drift x-ray detectors in order to study the low-energy $\\bar{K}$-nucleus strong interaction. The energy of the $3d \\to 2p$ transition was determined to be 6467 $\\pm$ 3 (stat) $\\pm$ 2 (syst) eV. The resulting strong-interaction energy-level shift is in agreement with theoretical calculations, thus eliminating a long-standing discrepancy between theory and experiment.

  7. Precision measurement of the 3 d → 2 p x-ray energy in kaonic 4He

    Okada, S.; Beer, G.; Bhang, H.; Cargnelli, M.; Chiba, J.; Choi, Seonho; Curceanu, C.; Fukuda, Y.; Hanaki, T.; Hayano, R. S.; Iio, M.; Ishikawa, T.; Ishimoto, S.; Ishiwatari, T.; Itahashi, K.; Iwai, M.; Iwasaki, M.; Juhász, B.; Kienle, P.; Marton, J.; Matsuda, Y.; Ohnishi, H.; Outa, H.; Sato, M.; Schmid, P.; Suzuki, S.; Suzuki, T.; Tatsuno, H.; Tomono, D.; Widmann, E.; Yamazaki, T.; Yim, H.; Zmeskal, J.

    2007-09-01

    We have measured the Balmer-series x-rays of kaonic 4He atoms using novel large-area silicon drift x-ray detectors in order to study the low-energy Kbar-nucleus strong interaction. The energy of the 3 d → 2 p transition was determined to be 6467 ± 3 (stat) ± 2 (syst) eV. The resulting strong-interaction energy-level shift is in agreement with theoretical calculations, thus eliminating a long-standing discrepancy between theory and experiment.

  8. Precision measurement of the 3d{yields}2p x-ray energy in kaonic {sup 4}He

    Okada, S. [RIKEN Nishina Center, RIKEN, Saitama 351-0198 (Japan)], E-mail: sokada@riken.jp; Beer, G. [Department of Physics and Astronomy, University of Victoria, British Columbia V8W 3P6 (Canada); Bhang, H. [Department of Physics, Seoul National University, Seoul 151-742 (Korea, Republic of); Cargnelli, M. [Stefan Meyer Institut fuer subatomare Physik, Austrian Academy of Sciences, A-1090 Vienna (Austria); Chiba, J. [Department of Physics, Tokyo University of Science, Chiba 278-8510 (Japan); Choi, Seonho [Department of Physics, Seoul National University, Seoul 151-742 (Korea, Republic of); Curceanu, C. [Laboratori Nazionali di Frascati, INFN, I-00044 Frascati (Italy); Fukuda, Y. [Department of Physics, Tokyo Institute of Technology, Tokyo 152-8551 (Japan); Hanaki, T. [Department of Physics, Tokyo University of Science, Chiba 278-8510 (Japan); Hayano, R.S. [Department of Physics, University of Tokyo, Tokyo 113-0033 (Japan); Iio, M. [RIKEN Nishina Center, RIKEN, Saitama 351-0198 (Japan); Ishikawa, T. [Department of Physics, University of Tokyo, Tokyo 113-0033 (Japan); Ishimoto, S. [High Energy Accelerator Research Organization (KEK), Ibaraki 305-0801 (Japan); Ishiwatari, T. [Stefan Meyer Institut fuer subatomare Physik, Austrian Academy of Sciences, A-1090 Vienna (Austria); Itahashi, K. [RIKEN Nishina Center, RIKEN, Saitama 351-0198 (Japan); Iwai, M. [High Energy Accelerator Research Organization (KEK), Ibaraki 305-0801 (Japan); Iwasaki, M. [RIKEN Nishina Center, RIKEN, Saitama 351-0198 (Japan); Department of Physics, Tokyo Institute of Technology, Tokyo 152-8551 (Japan); Juhasz, B. [Stefan Meyer Institut fuer subatomare Physik, Austrian Academy of Sciences, A-1090 Vienna (Austria); Kienle, P. [Stefan Meyer Institut fuer subatomare Physik, Austrian Academy of Sciences, A-1090 Vienna (Austria); Physik Department, Technische Universitaet Muenchen, D-85748 Garching (Germany)] (and others)

    2007-09-27

    We have measured the Balmer-series x-rays of kaonic {sup 4}He atoms using novel large-area silicon drift x-ray detectors in order to study the low-energy K-bar -nucleus strong interaction. The energy of the 3d{yields}2p transition was determined to be 6467{+-}3(stat){+-}2(syst) eV. The resulting strong-interaction energy-level shift is in agreement with theoretical calculations, thus eliminating a long-standing discrepancy between theory and experiment.

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

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

  10. Crystallization and preliminary X-ray diffraction studies of infectious bronchitis virus nonstructural protein 9

    Ma, Yanlin; Chen, Cheng; Wei, Lei; Yang, Qingzhu; Liao, Ming; Li, Xuemei

    2010-01-01

    The gene segment encoding avian infectious bronchitis virus nonstructural protein 9 has been cloned and expressed in Escherichia coli. The protein has been crystallized and the crystals diffracted X-rays to 2.44 Å resolution.