Sample records for x-ray diffraction xrd

  1. Nanofabrication of Diffractive X-ray Optics for Synchrotrons...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    the soft x-ray range and down to 15 nm in the multi keV range. For use at x-ray free-electron laser (XFEL) sources, diffractive optics must be capable of withstanding extreme...

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

    SciTech Connect (OSTI)

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

    1997-12-01T23:59:59.000Z

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

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

    SciTech Connect (OSTI)

    Sun, Cheng-Jun, E-mail: cjsun@aps.anl.gov; Brewe, Dale L.; Heald, Steve M. [Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439 (United States)] [Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Zhang, Bangmin [Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439 (United States) [Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Department of Materials Science and Engineering, National University of Singapore, 117575 Singapore (Singapore); NUSNNI-Nanocore, National University of Singapore, 117411 Singapore (Singapore); Chen, Jing-Sheng; Chow, G. M. [Department of Materials Science and Engineering, National University of Singapore, 117575 Singapore (Singapore)] [Department of Materials Science and Engineering, National University of Singapore, 117575 Singapore (Singapore); Venkatesan, T. [NUSNNI-Nanocore, National University of Singapore, 117411 Singapore (Singapore) [NUSNNI-Nanocore, National University of Singapore, 117411 Singapore (Singapore); Department of Physics, National University of Singapore, 117542 Singapore (Singapore); Department of Electrical and Computer Engineering, National University of Singapore, 117575 Singapore (Singapore)

    2014-04-15T23:59:59.000Z

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

  4. Residual stress measurement using X-ray diffraction 

    E-Print Network [OSTI]

    Anderoglu, Osman

    2005-02-17T23:59:59.000Z

    .3.6.2. Synchrotron Diffraction.........................................................................9 II. FUNDAMENTAL CONCEPTS IN X-RAY DIFFRACTION.....................................12 2.1. X-ray Source... radiations ...................................................................16 Table 2.2 Structure factors and reflection conditions ...................................................20 Table 4.1 Chemical composition of SS316...

  5. In Operando X-ray Diffraction and Transmission X-ray Microscopy of Lithium Sulfur Batteries

    E-Print Network [OSTI]

    Cui, Yi

    In Operando X-ray Diffraction and Transmission X-ray Microscopy of Lithium Sulfur Batteries Johanna Information ABSTRACT: Rechargeable lithium-sulfur (Li-S) batteries hold great potential for high of these batteries for commercial use. The two primary obstacles are the solubility of long chain lithium

  6. Response Time Measurements of the NIF DANTE XRD-31 X-Ray Diodes (Pre-print)

    SciTech Connect (OSTI)

    Don Pellinen and Michael Griffin

    2009-01-23T23:59:59.000Z

    The XRD-31 is a fast, windowless X-ray vacuum photodiode developed by EG&G. It is currently the primary fast X-ray detector used to diagnose the X-rays on NIF and OMEGA on the multichannel DANTE spectrometer. The XRD-31 has a dynamic range of less than 1e-12 amps to more than 10 amps. A technique is described to measure the impulse response of the diodes to a 150 fs pulse of 200 nm laser light and a method to calculate the “risetime” for a square pulse and compare it with the computed electron transit time from the photocathode to the anode. Measured response time for 5 XRD-31s assembled in early 2004 was 149.7 ps +-2.75 ps.

  7. X-Ray Diffraction Microscopy of Magnetic Structures

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    12.0.2.2 Citation: J.J. Turner et al., "X-Ray Diffraction Microscopy of Magnetic Structures," Phys. Rev. Lett. 107, 033904 (2011). Web: http:prl.aps.orgpdfPRLv107i3e033904...

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

    SciTech Connect (OSTI)

    Van Swygenhoven, Helena, E-mail: helena.vanswygenhoven@psi.ch; Van Petegem, Steven

    2013-04-15T23:59:59.000Z

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

  9. X-Ray Diffraction Microscopy of Magnetic Structures

    SciTech Connect (OSTI)

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

    2011-07-14T23:59:59.000Z

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

  10. Biological imaging by soft x-ray diffraction microscopy

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Shapiro, D. [Stony Brook Univ., Stony Brook, NY (United States); Thibault, P. [Cornell Univ., Ithaca, NY (United States); Beetz, T. [Stony Brook Univ., Stony Brook, NY (United States); Brookhaven National Lab., Upton, NY (United States). Center for Functional Nanomaterials; Elser, V. [Cornell Univ., Ithaca, NY (United States); Howells, M. [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States). Advanced Light Source; Jacobsen, C. [Stony Brook Univ., Stony Brook, NY (United States); Brookhaven National Lab., Upton, NY (United States). Center for Functional Nanomaterials; Kirz, J. [Stony Brook Univ., Stony Brook, NY (United States); Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States). Advanced Light Source; Lima, E. [Stony Brook Univ., Stony Brook, NY (United States); Miao, H. [Stony Brook Univ., Stony Brook, NY (United States); Neiman, A. M. [State Univ. of New York at Stony Brook, NY (United States); Sayre, D. [Stony Brook Univ., Stony Brook, NY (United States)

    2005-10-25T23:59:59.000Z

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

  11. Biological Imaging by Soft X-ray Diffraction Microscopy

    SciTech Connect (OSTI)

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

    2005-01-01T23:59:59.000Z

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

  12. X-ray server : an outline resource for simulations of x-ray diffraction and scattering.

    SciTech Connect (OSTI)

    Stepanov, S.; Biosciences Division

    2004-01-01T23:59:59.000Z

    X-ray Server is a public project operational at the APS since 1997 with the goals to explore novel network technologies for providing wide scientific community with access to personal research results, establishing scientific collaborations, and refining scientific software. The Server provides Web-based access to a number of programs developed by the author in the field of X-ray diffraction and scattering. The software code operates directly on the Server available for use without downloading. Currently seven programs are accessible that have been used more than 85,000 times. This report discusses the Server philosophy, provides an overview of the physical models and algorithms beneath the codes and demonstrates some applications of the programs. It is shown with examples and statistics how the Server goals are achieved. The plans for further X-ray Server development are outlined.

  13. Single photon energy dispersive x-ray diffraction

    SciTech Connect (OSTI)

    Higginbotham, Andrew; Patel, Shamim; Ciricosta, Orlando; Suggit, Matthew J.; Wark, Justin S. [Department of Physics, Clarendon Laboratory, University of Oxford, Parks Road, Oxford OX1 3PU (United Kingdom)] [Department of Physics, Clarendon Laboratory, University of Oxford, Parks Road, Oxford OX1 3PU (United Kingdom); Hawreliak, James A.; Collins, Gilbert W.; Coppari, Federica; Eggert, Jon H. [Lawrence Livermore National Laboratory, Livermore, California 94551 (United States)] [Lawrence Livermore National Laboratory, Livermore, California 94551 (United States); Tang, Henry [Department of Earth and Planetary Science, University of California Berkeley, Berkeley, California 94720 (United States)] [Department of Earth and Planetary Science, University of California Berkeley, Berkeley, California 94720 (United States)

    2014-03-15T23:59:59.000Z

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

  14. Fourier analysis of X-ray micro-diffraction profiles to characterize laser shock peened metals

    E-Print Network [OSTI]

    Yao, Y. Lawrence

    .L., 1950. The effect of cold-work distortion on X-ray pat- terns. Journal of Applied Physics 21, 595LSP need to be further studied from the measured X-ray micro-diffraction profile. Broadening of X-rayFourier analysis of X-ray micro-diffraction profiles to characterize laser shock peened metals

  15. Formation of delta ferrite in 9 wt.% Cr steel investigated by in-situ X-ray diffraction using synchrotron radiation

    E-Print Network [OSTI]

    Mayr, P.

    In-situ X-ray diffraction (XRD) measurements using high energy synchrotron radiation were performed to monitor in real time the formation of delta ferrite in a martensitic 9 wt pct chromium steel under simulated weld thermal ...

  16. Category:X-Ray Diffraction (XRD) | Open Energy Information

    Open Energy Info (EERE)

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  17. X-Ray Diffraction (XRD) | Open Energy Information

    Open Energy Info (EERE)

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  18. Portable X-Ray Diffraction (XRD) | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov YouKizildere I Geothermal PwerPerkins County, Nebraska: EnergyPiratiniEdwards, Wisconsin: EnergyReading, NewJumpPortable

  19. Borman effect in resonant diffraction of X-rays

    SciTech Connect (OSTI)

    Oreshko, A. P., E-mail: ap.oreshko@physics.msu.ru [Moscow State University (Russian Federation)

    2013-08-15T23:59:59.000Z

    A dynamic theory of resonant diffraction (occurring when the energy of incident radiation is close to the energy of the absorption edge of an element in the composition of a given substance) of synchronous X-rays is developed in the two-wave approximation in the coplanar Laue geometry for large grazing angles in perfect crystals. A sharp decrease in the absorption coefficient in the substance with simultaneously satisfied diffraction conditions (Borman effect) is demonstrated, and the theoretical and first experimental results are compared. The calculations reveal the possibility of applying this approach in analyzing the quadrupole-quadrupole contribution to the absorption coefficient.

  20. Quality experimental and calculated powder x-ray diffraction

    SciTech Connect (OSTI)

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

    1996-08-01T23:59:59.000Z

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

  1. Characterization of Microstructure of Severely Deformed Titanium by X-ray Diffraction Profile Analysis

    E-Print Network [OSTI]

    Gubicza, Jenõ

    Characterization of Microstructure of Severely Deformed Titanium by X-ray Diffraction Profile deformation, X-ray peak profile analysis. Abstract. Nanocrystalline titanium was produced by equal channel of the measured X-ray diffraction peak profiles. The peak profile analysis provided the median and the variance

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

    SciTech Connect (OSTI)

    Dane V. Morgan, Don Macy, Gerald Stevens

    2008-11-22T23:59:59.000Z

    A new, fast, single-pulse x-ray diffraction (XRD) diagnostic for determining phase transitions in shocked polycrystalline materials has been developed. The diagnostic consists of a 37-stage Marx bank high-voltage pulse generator coupled to a needle-and-washer electron beam diode via coaxial cable, producing line and bremsstrahlung x-ray emission in a 35-ns pulse. The characteristic K? lines from the selected anodes of silver and molybdenum are used to produce the diffraction patterns, with thin foil filters employed to remove the characteristic K? line emission. The x-ray beam passes through a pinhole collimator and is incident on the sample with an approximately 3-mm by 6-mm spot and 1° full-width-half-maximum (FWHM) angular divergence in a Bragg-reflecting geometry. For the experiments described in this report, the angle between the incident beam and the sample surface was 8.5°. A Debye-Scherrer diffraction image was produced on a phosphor located 76 mm from the polycrystalline sample surface. The phosphor image was coupled to a charge-coupled device (CCD) camera through a coherent fiberoptic bundle. Dynamic single-pulse XRD experiments were conducted with thin foil samples of tin, shock loaded with a 1-mm vitreous carbon back window. Detasheet high explosive with a 2-mm-thick aluminum buffer was used to shock the sample. Analysis of the dynamic shock-loaded tin XRD images revealed a phase transformation of the tin beta phase into an amorphous or liquid state. Identical experiments with shock-loaded aluminum indicated compression of the face-centered-cubic (fcc) aluminum lattice with no phase transformation.

  3. Anomalous X-ray Diffraction Studies for Photovoltaic Applications

    SciTech Connect (OSTI)

    Not Available

    2011-06-22T23:59:59.000Z

    Anomalous X-ray Diffraction (AXRD) has become a useful technique in characterizing bulk and nanomaterials as it provides specific information about the crystal structure of materials. In this project we present the results of AXRD applied to materials for photovoltaic applications: ZnO loaded with Ga and ZnCo{sub 2}O{sub 4} spinel. The X-ray diffraction data collected for various energies were plotted in Origin software. The peaks were fitted using different functions including Pseudo Voigt, Gaussian, and Lorentzian. This fitting provided the integrated intensity data (peaks area values), which when plotted as a function of X-ray energies determined the material structure. For the first analyzed sample, Ga was not incorporated into the ZnO crystal structure. For the ZnCo{sub 2}O{sub 4} spinel Co was found in one or both tetrahedral and octahedral sites. The use of anomalous X-ray diffraction (AXRD) provides element and site specific information for the crystal structure of a material. This technique lets us correlate the structure to the electronic properties of the materials as it allows us to probe precise locations of cations in the spinel structure. What makes it possible is that in AXRD the diffraction pattern is measured at a number of energies near an X-ray absorption edge of an element of interest. The atomic scattering strength of an element varies near its absorption edge and hence the total intensity of the diffraction peak changes by changing the X-ray energy. Thus AXRD provides element specific structural information. This method can be applied to both crystalline and liquid materials. One of the advantages of AXRD in crystallography experiments is its sensitivity to neighboring elements in the periodic tables. This method is also sensitive to specific crystallographic phases and to a specific site in a phase. The main use of AXRD in this study is for transparent conductors (TCs) analysis. TCs are considered to be important materials because of their efficiency and low risk of environmental pollution. These materials are important to solar cells as a result of their remarkable combination of optical and electrical properties, including high electrical conductivity and high optical transparency in the spectrum of visible light. TCs provide a transparent window, which allows sunlight to pass through while also allowing electricity to conduct out of the cell. Spinel materials have the chemical form AB{sub 2}O{sub 4}, and are made of a face-centered cubic (FCC) lattice of oxygen anions and cations in specific interstitial sites. A normal spinel has all A cations on tetrahedral sites and B cations on octahedral sites. In contrast; an inverse spinel has the A and half of the B cations on octahedral sites and the other half of the B cations on tetrahedral sites; a mixed spinel lies between. In the spinel structure, 8 of 64 possible tetrahedral sites and 16 of 32 possible octahedral sites are filled. Normal spinels have particularly high conduction as the linear octahedral chains of B cations likely serve as conduction paths. In this paper we present how the data obtained with AXRD is used to analyze TCs properties as they apply to photovoltaic applications. One of the materials used for this analysis is zinc oxide. It has been loaded with 5% and 10% of Ga, which has an absorption edge of 10367 eV. The peak (100) was measured for the zinc oxide loaded with 10% Ga. In the case of 5% Ga, we measured peaks (100) and (101). With the information provided by the AXRD we can identify if Ga is being incorporated in the ZnO crystal structure. The analysis of 311 plane in the ZnCo{sub 2}O{sub 4} spinel shows if Co is in tetrahedral or octahedral site.

  4. Quantification of thin film crystallographic orientation using X-ray diffraction with an area detector

    E-Print Network [OSTI]

    Baker, Jessica L

    2010-01-01T23:59:59.000Z

    elastic  properties of Au thin films by X?ray diffraction interface in  polythiophene thin?film transistors.  Nat copper  phthalocyanine thin films evaporated on amorphous 

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

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

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

    2009-11-01T23:59:59.000Z

    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 degrees C, artifacts due to dehydration, ice crystallization, and radiation damage are greatly reduced. In this example, coherent diffraction data using 520 eV x rays were recorded and reconstructed to reveal a budding yeast cell at a resolution better than 25 nm. This demonstration represents an important step towards high resolution imaging of cells in their natural, hydrated state, without limitations imposed by x-ray optics.

  6. Probing Martensitic Transition in Nitinol Wire: A Comparison of X-ray Diffraction and Other Techniques

    SciTech Connect (OSTI)

    Butler, J.; Tiernan, P.; Tofail, S. A. M.; Ghandi, A. A. [Materials and Surface Science Institute, University of Limerick, Limerick (Ireland)

    2011-01-17T23:59:59.000Z

    Martensitic to austenite transformation in Nitinol wire can be measured by a number of techniques such as XRD (X-Ray Diffraction), DSC (Differential Scanning Calorimetry), BFR (Bend and Free Recovery) and Vickers indentation recovery. A comparison of results from these varied characterisation techniques is reported here to obtain a greater understanding of the thermal-elastic-structural changes associated with martensitic transformation. The transformation temperatures measured by DSC were found to correspond well with the structural and mechanical information obtained from XRD, BFR and Vickers indent recovery methods. Indent recovery is a relatively new and accurate method of monitoring stress induced martensitic transformations in NiTi and is one of only a few methods of stress inducing martensitic transformation in large scale samples. It is especially useful for NiTi in the as-cast billet form, where tensile testing is impossible. BFR is uniquely popular in the NiTi wire manufacturing sector and is recognised as the most accurate method of measuring the transformation temperature. Here the material is stressed to a representative in-service stress level during the test. No other test uses the shape memory effect for measuring the transformation temperature of NiTi. The results show that the DSC thermogram and XRD diffractogram have a peak overlap which is a common occurrence in NiTi that has been extensively processed. The XRD method further explains the observations in the DSC thermogram and in combination they confirm the transformation temperature.

  7. Advances in X-Ray Chemical Analysis, Japan, 41 (2010) ISSN 0911-7806 Theoretical Analysis of X-Ray Waveguide Using Fresnel Diffraction

    E-Print Network [OSTI]

    Jun, Kawai

    2010-01-01T23:59:59.000Z

    -Ray Waveguide Using Fresnel Diffraction Yusuke MORIKAWA and Jun KAWAI #12;#12;41 145 X Adv. X-Ray. Chem. Anal., Japan 41, pp.145-150 (2010) 606-8501 X Theoretical Analysis of X-Ray Waveguide Using Fresnel Diffraction symmetrical pattern. We regard it as a slit and calculated the Fresnel diffraction. We find

  8. Residual stress measurement using X-ray diffraction

    E-Print Network [OSTI]

    Anderoglu, Osman

    2005-02-17T23:59:59.000Z

    -rays..............................................................................................16 2.4. Bragg's Law ..........................................................................................................18 2.5. Diffractometer Geometry... Figure 2.2 Schematic showing the basic components of a modern x-ray tube. Beryllium window is highly transparent to x-rays...............................15 Figure 2.3 Coherent scattering from an electron to a point P...

  9. Spectral Resolution for Five-Element, Filtered, X-Ray Detector (XRD) Arrays Using the Methods of Backus and Gilbert

    SciTech Connect (OSTI)

    FEHL,DAVID LEE; BIGGS,F.; CHANDLER,GORDON A.; STYGAR,WILLIAM A.

    2000-01-17T23:59:59.000Z

    The generalized method of Backus and Gilbert (BG) is described and applied to the inverse problem of obtaining spectra from a 5-channel, filtered array of x-ray detectors (XRD's). This diagnostic is routinely fielded on the Z facility at Sandia National Laboratories to study soft x-ray photons ({le}2300 eV), emitted by high density Z-pinch plasmas. The BG method defines spectral resolution limits on the system of response functions that are in good agreement with the unfold method currently in use. The resolution so defined is independent of the source spectrum. For noise-free, simulated data the BG approximating function is also in reasonable agreement with the source spectrum (150 eV black-body) and the unfold. This function may be used as an initial trial function for iterative methods or a regularization model.

  10. X-ray Diffraction from Membrane Protein Nanocrystals

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of ScienceandMesa del SolStrengtheningWildfires may contribute more toConsensusX-RayX-RayX-ray

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

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

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

    2011-05-01T23:59:59.000Z

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

  12. Integration of a broad beam ion source with a high-temperature x-ray diffraction vacuum chamber

    SciTech Connect (OSTI)

    Manova, D.; Bergmann, A.; Maendl, S.; Neumann, H.; Rauschenbach, B. [Leibniz-Institut fuer Oberflaechenmodifizierung e. V., Permoserstr. 15, 04318 Leipzig (Germany)

    2012-11-15T23:59:59.000Z

    Here, the integration of a low energy, linearly variable ion beam current density, mechanically in situ adjustable broad beam ion source with a high-temperature x-ray diffraction (XRD) vacuum chamber is reported. This allows in situ XRD investigation of phase formation and evolution processes induced by low energy ion implantation. Special care has been taken to an independent adjustment of the ion beam for geometrical directing towards the substrate, a 15 mm small ion source exit aperture to avoid a secondary sputter process of the chamber walls, linearly variable ion current density by using a pulse length modulation (PLM) for the accelerating voltages without changing the ion beam density profile, nearly homogeneous ion beam distribution over the x-ray footprint, together with easily replaceable Kapton{sup Registered-Sign} windows for x-rays entry and exit. By combining a position sensitive x-ray detector with this PLM-modulated ion beam, a fast and efficient time resolved investigation of low energy implantation processes is obtained in a compact experimental setup.

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

    DOE Patents [OSTI]

    Berman, Robert M. (Pittsburgh, PA); Cohen, Isadore (Pittsburgh, PA)

    1990-01-01T23:59:59.000Z

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

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

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

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

    2010-04-20T23:59:59.000Z

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

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

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

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

    2006-01-01T23:59:59.000Z

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

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

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Nelson, Johanna [Stony Brook Univ., Stony Brook, NY (United States); Huang, Xiaojing [Stony Brook Univ., Stony Brook, NY (United States); Steinbrener, Jan [Stony Brook Univ., Stony Brook, NY (United States); Shapiro, David [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States). Advanced Light Source; Kirz, Janos [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States). Advanced Light Source; Marchesini, Stephano [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States). Advanced Light Source; Neiman, Aaron M. [Northwestern Univ., Evanston, IL (United States); Turner, Joshua J. [Stony Brook Univ., Stony Brook, NY (United States); Jacobsen, Chris [Stony Brook Univ., Stony Brook, NY (United States); Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States). Advanced Light Source; Argonne National Laboratory (ANL), Argonne, IL (United States). Advanced Photon Source

    2010-04-20T23:59:59.000Z

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

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

    SciTech Connect (OSTI)

    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

    2005-08-19T23:59:59.000Z

    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.

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

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

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

    2006-01-01T23:59:59.000Z

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

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

    SciTech Connect (OSTI)

    Kycia, S.

    1996-04-23T23:59:59.000Z

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

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

    SciTech Connect (OSTI)

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

    2014-02-28T23:59:59.000Z

    Here we present femtosecond x-ray diffraction patterns from two-dimensional (2-D) protein crystals using an x-ray free electron laser (XFEL). To date it has not been possible to acquire x-ray diffraction from individual 2-D protein crystals due to radiation damage. However, the intense and ultrafast pulses generated by an XFEL permits a new method of collecting diffraction data before the sample is destroyed. Utilizing a diffract-before-destroy methodology at the Linac Coherent Light Source, we observed Bragg diffraction to better than 8.5 Å resolution for two different 2-D protein crystal samples that were maintained at room temperature. These proof-of-principle results show promise for structural analysis of both soluble and membrane proteins arranged as 2-D crystals without requiring cryogenic conditions or the formation of three-dimensional crystals.

  1. SCANNING ELECTRON MICROSCOPY AND X-RAY DIFFRACTION ANALYSIS OF TANK 18 SAMPLES

    SciTech Connect (OSTI)

    Hay, M.; O'Rourke, P.; Ajo, H.

    2012-03-08T23:59:59.000Z

    The F-Area Tank Farm (FTF) Performance Assessment (PA) utilizes waste speciation in the waste release model used in the FTF fate and transport modeling. The waste release modeling associated with the residual plutonium in Tank 18 has been identified as a primary contributor to the Tank 18 dose uncertainty. In order to reduce the uncertainty related to plutonium in Tank 18, a better understanding of the plutonium speciation in the Tank 18 waste (including the oxidation state and stoichiometry) is desired. Savannah River National Laboratory (SRNL) utilized Scanning Electron Microscopy (SEM) and X-ray Diffraction (XRD) to analyze Tank 18 samples to provide information on the speciation of plutonium in the waste material. XRD analysis of the Tank 18 samples did not identify any plutonium mineral phases in the samples. These indicates the crystalline mineral phases of plutonium are below the detection limits of the XRD method or that the plutonium phase(s) lack long range order and are present as amorphous or microcrystalline solids. SEM analysis of the Tank 18 samples did locate particles containing plutonium. The plutonium was found as small particles, usually <1 {micro}m but ranging up to several micrometers in diameter, associated with particles of an iron matrix and at low concentration in other elemental matrices. This suggests the plutonium has an affinity for the iron matrix. Qualitatively, the particles of plutonium found in the SEM analysis do not appear to account for all of the plutonium in the sample based on concentrations determined from the chemical analysis of the Tank 18 samples. This suggests that plutonium is also distributed throughout the solids in low concentrations.

  2. X-Ray Diffraction Microscopy of Magnetic Structures

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurThe Iron SpinPrincetonUsingWhat isJoin theanniversaryI 1 0 3 P 0 d d X O O lX-Ray

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

    DOE Patents [OSTI]

    Pawloski, G.A.

    1984-08-10T23:59:59.000Z

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

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

    SciTech Connect (OSTI)

    Sharkov, M. D., E-mail: mischar@mail.ioffe.ru; Boiko, M. E.; Bobyl, A. V.; Ershenko, E. M.; Terukov, E. I. [Russian Academy of Sciences, Ioffe Physical-Technical Institute (Russian Federation); Zubavichus, Y. V. [National Research Centre “Kurchatov Institute” (Russian Federation)

    2013-12-15T23:59:59.000Z

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

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

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

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

    2009-01-01T23:59:59.000Z

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

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

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

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

    2009-01-01T23:59:59.000Z

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

  7. Methodology for Optimal In Situ Alignment and Setting of Bendable Optics for Diffraction-Limited Focusing of Soft X-Rays

    E-Print Network [OSTI]

    Merthe, Daniel

    2013-01-01T23:59:59.000Z

    mirrors, x-rays, x-ray optics, synchrotron radiation,beamline, Kirkpatrick-Baez, metrology of x-ray opticsand Setting of Bendable Optics for Diffraction-Limited

  8. Impulsive solvent heating probed by picosecond x-ray diffraction M. Cammarata

    E-Print Network [OSTI]

    Ihee, Hyotcherl

    Impulsive solvent heating probed by picosecond x-ray diffraction M. Cammarata European Synchrotron and J. H. Lee Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST of Science and Technology (KAIST), Daejeon 305-701, Republic of Korea Q. Y. Kong European Synchrotron

  9. Radial x-ray diffraction of tungsten tetraboride to 86 GPa under nonhydrostatic compression

    E-Print Network [OSTI]

    Lin, Jung-Fu "Afu"

    Radial x-ray diffraction of tungsten tetraboride to 86 GPa under nonhydrostatic compression Lun December 2012; published online 16 January 2013) Investigations of the equation of state of tungsten moduli and hardness exceed- ing or closing that of diamond. Tungsten tetraboride (WB4) is a candidate

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

    DOE Patents [OSTI]

    Smither, Robert K. (Hinsdale, IL)

    2011-05-17T23:59:59.000Z

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

  11. Soft X-Ray Diffraction Microscopy of a Frozen Hydrated Yeast Cell Xiaojing Huang,1

    E-Print Network [OSTI]

    Mohseni, Hooman

    crystallization, and radiation damage are greatly reduced. In this example, coherent diffraction data using 520 e of biological electron microscopy [1­3]. Radiation damage precludes repeated imaging of live specimens [4 in their natural, hydrated state, without limitations imposed by x-ray optics. DOI: 10.1103/PhysRevLett.103

  12. Diffraction crystals for sagittally focusing x-rays

    DOE Patents [OSTI]

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

    1982-06-07T23:59:59.000Z

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

  13. Diffraction crystal for sagittally focusing x-rays

    DOE Patents [OSTI]

    Ice, Gene E. (Oak Ridge, TN); Sparks, Jr., Cullie J. (Oak Ridge, TN)

    1984-01-01T23:59:59.000Z

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

  14. X-ray diffraction study of the static strength of tungsten to 69 GPa Duanwei He* and Thomas S. Duffy

    E-Print Network [OSTI]

    Duffy, Thomas S.

    X-ray diffraction study of the static strength of tungsten to 69 GPa Duanwei He* and Thomas S of tungsten was determined under static high pressures to 69 GPa using x-ray diffraction techniques strength of tungsten increases with compression, reaching a value of 5.3 GPa at the highest pressure

  15. Cs-Exchange in Birnessite: Raction Mechanisms Inferred from Time-Resolved X-ray Diffraction and Transmission Electron Microscopy

    SciTech Connect (OSTI)

    Lopano, C.; Heaney, P; Post, J

    2009-01-01T23:59:59.000Z

    We have explored the exchange of Cs for interlayer Na in birnessite using several techniques, including transmission electron microscopy (TEM) and time-resolved synchrotron X-ray diffraction (XRD). Our goal was to test which of two possible exchange mechanisms is operative during the reaction: (1) diffusion of cations in and out of the interlayer or (2) dissolution of Na-birnessite and reprecipitation of Cs-birnessite. The appearance of distinct XRD peaks for Na- and Cs-rich phases in partially exchanged samples offered support for a simple diffusion model, but it was inconsistent with the compositional and crystallographic homogeneity of (Na,Cs)-birnessite platelets from core to rim as ascertained by TEM. Time-resolved XRD revealed systematic changes in the structure of the emergent Cs-rich birnessite phase during exchange, in conflict with a dissolution and reprecipitation model. Instead, we propose that exchange occurred by sequential delamination of Mn oxide octahedral sheets. Exfoliation of a given interlayer region allowed for wholesale replacement of Na by Cs and was rapidly followed by reassembly. This model accounts for the rapidity of metal exchange in birnessite, the co-existence of distinct Na- and Cs-birnessite phases during the process of exchange, and the uniformly mixed Na- and Cs-compositions ascertained from point analyses by selected area electron diffraction and energy dispersive spectroscopy of partially exchanged grains.

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

    SciTech Connect (OSTI)

    Terwilliger, T.C.; Berendzen, J.

    1998-02-25T23:59:59.000Z

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

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

    SciTech Connect (OSTI)

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

    2009-09-01T23:59:59.000Z

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

  18. Apparatus for X-ray diffraction microscopy and tomography of cryo specimens

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Beetz, T.; Howells, M. R.; Jacobsen, C.; Kao, C. -C.; Kirz, J.; Lima, E.; Mentes, T. O.; Miao, H.; Sanchez-Hanke, C.; Sayre, D.; et al

    2005-06-01T23:59:59.000Z

    An apparatus for diffraction microscopy of biological and materials science specimens is described. In this system, a coherent soft X-ray beam is selected with a pinhole, and the illuminated specimen is followed by an adjustable beamstop and CCD camera to record diffraction data from non-crystalline specimens. In addition, a Fresnel zone plate can be inserted to allow for direct imaging. The system makes use of a cryogenic specimen holder with cryotransfer capabilities to allow frozen hydrated specimens to be loaded. The specimen can be tilted over a range of ± 80 ° degrees for three-dimensional imaging; this is done bymore »computer-controlled motors, enabling automated alignment of the specimen through a tilt series. The system is now in use for experiments in soft X-ray diffraction microscopy.« less

  19. Apparatus for X-ray diffraction microscopy and tomography of cryo specimens

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Beetz, T.; Howells, M.R.; Jacobsen, C.; Kao, C.-C.; Kirz, J.; Lima, E.; Mentes, T.O.; Miao, H.; Sanchez-Hanke, C.; Sayre, D.; Shapiro, D.

    2005-06-01T23:59:59.000Z

    An apparatus for diffraction microscopy of biological and materials science specimens is described. In this system, a coherent soft X-ray beam is selected with a pinhole, and the illuminated specimen is followed by an adjustable beamstop and CCD camera to record diffraction data from non-crystalline specimens. In addition, a Fresnel zone plate can be inserted to allow for direct imaging. The system makes use of a cryogenic specimen holder with cryotransfer capabilities to allow frozen hydrated specimens to be loaded. The specimen can be tilted over a range of +/- 80 degrees for three-dimensional imaging; this is done by computer-controlled motors, enabling automated alignment of the specimen through a tilt series. The system is now in use for experiments in soft X-ray diffraction microscopy.

  20. Apparatus for X-ray diffraction microscopy and tomography of cryo specimens

    SciTech Connect (OSTI)

    Beetz, T. [Stony Brook Univ., Stony Brook, NY (United States); Howells, M. R. [Brookhaven National Laboratory (BNL), Upton, NY (United States). National Synchrotron Light Source; Brookhaven National Laboratory (BNL), Upton, NY (United States). Center for Functional Nanomaterials; Jacobsen, C. [Stony Brook Univ., Stony Brook, NY (United States); Kao, C. -C. [Brookhaven National Laboratory (BNL), Upton, NY (United States). National Synchrotron Light Source; Kirz, J. [Stony Brook Univ., Stony Brook, NY (United States); Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States). Advanced Light Source; Lima, E. [Stony Brook Univ., Stony Brook, NY (United States); Mentes, T. O. [Stony Brook Univ., Stony Brook, NY (United States); TASC-INFM National Lab, Trieste (Italy); Miao, H. [Stony Brook Univ., Stony Brook, NY (United States); Sanchez-Hanke, C. [Brookhaven National Laboratory (BNL), Upton, NY (United States). National Synchrotron Light Source; Sayre, D. [Stony Brook Univ., Stony Brook, NY (United States); Shapiro, D. [Stony Brook Univ., Stony Brook, NY (United States)

    2005-06-01T23:59:59.000Z

    An apparatus for diffraction microscopy of biological and materials science specimens is described. In this system, a coherent soft X-ray beam is selected with a pinhole, and the illuminated specimen is followed by an adjustable beamstop and CCD camera to record diffraction data from non-crystalline specimens. In addition, a Fresnel zone plate can be inserted to allow for direct imaging. The system makes use of a cryogenic specimen holder with cryotransfer capabilities to allow frozen hydrated specimens to be loaded. The specimen can be tilted over a range of ± 80 ° degrees for three-dimensional imaging; this is done by computer-controlled motors, enabling automated alignment of the specimen through a tilt series. The system is now in use for experiments in soft X-ray diffraction microscopy.

  1. Realizing in-plane surface diffraction by x-ray multiple-beam diffraction with large incidence angle

    SciTech Connect (OSTI)

    Huang, Xian-Rong, E-mail: xiahuang@aps.anl.gov; Gog, Thomas; Assoufid, Lahsen [Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Peng, Ru-Wen, E-mail: rwpeng@nju.edu.cn [National Laboratory of Solid State Microstructures and Department of Physics, Nanjing University, Nanjing 210093 (China); Siddons, D. P. [National Synchrotron Light Source, Brookhaven National Laboratory, Upton, New York 11973 (United States)

    2014-11-03T23:59:59.000Z

    Based on rigorous dynamical-theory calculations, we demonstrate the principle of an x-ray multiple-beam diffraction (MBD) scheme that overcomes the long-lasting difficulties of high-resolution in-plane diffraction from crystal surfaces. This scheme only utilizes symmetric reflection geometry with large incident angles but activates the out-of-plane and in-plane diffraction processes simultaneously and separately in the continuous MBD planes. The in-plane diffraction is realized by detoured MBD, where the intermediate diffracted waves propagate parallel to the surface, which corresponds to an absolute Bragg surface diffraction configuration that is extremely sensitive to surface structures. A series of MBD diffraction and imaging techniques may be developed from this principle to study surface/interface (misfit) strains, lateral nanostructures, and phase transitions of a wide range of (pseudo)cubic crystal structures, including ultrathin epitaxial films and multilayers, quantum dots, strain-engineered semiconductor or (multi)ferroic materials, etc.

  2. Method for characterizing mask defects using image reconstruction from X-ray diffraction patterns

    DOE Patents [OSTI]

    Hau-Riege, Stefan Peter (Fremont, CA)

    2007-05-01T23:59:59.000Z

    The invention applies techniques for image reconstruction from X-ray diffraction patterns on the three-dimensional imaging of defects in EUVL multilayer films. The reconstructed image gives information about the out-of-plane position and the diffraction strength of the defect. The positional information can be used to select the correct defect repair technique. This invention enables the fabrication of defect-free (since repaired) X-ray Mo--Si multilayer mirrors. Repairing Mo--Si multilayer-film defects on mask blanks is a key for the commercial success of EUVL. It is known that particles are added to the Mo--Si multilayer film during the fabrication process. There is a large effort to reduce this contamination, but results are not sufficient, and defects continue to be a major mask yield limiter. All suggested repair strategies need to know the out-of-plane position of the defects in the multilayer.

  3. X-Ray Diffraction Study of Elemental Erbium to 65 GPa

    SciTech Connect (OSTI)

    Pravica, M.G.; Lipinska-Kalita, K.; Quine, Z.; Romano, E.; Nicol, M.F. (UNLV)

    2006-02-02T23:59:59.000Z

    We have investigated phase transitions in elemental erbium in a diamond anvil cell up to 65 GPa using x-ray powder diffraction methods. We present preliminary evidence of a series of phase transitions that appear to follow the expected hcp {yields} Sm-type {yields} dhcp {yields} distorted fcc sequence. In particular, we believe that we have evidence for the predicted dhcp {yields} distorted fcc transition between 43 GPa and 65 GPa.

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

    SciTech Connect (OSTI)

    Haugh, M. J., E-mail: haughmj@nv.doe.gov; Jacoby, K. D. [National Security Technologies, LLC, Livermore, California 94550 (United States); Wu, M.; Loisel, G. P. [Sandia National Laboratories, Albuquerque, New Mexico 87123 (United States)

    2014-11-15T23:59:59.000Z

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

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

    SciTech Connect (OSTI)

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

    2014-09-15T23:59:59.000Z

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

  6. In-situ stress analysis with X-Ray diffraction for yield locus characterization of sheet metals

    SciTech Connect (OSTI)

    Güner, A.; Tekkaya, A. E. [Institute of Forming Technology and Lightweight Construction, TU Dortmund University, Baroper Str. 301, 44227 Dortmund (Germany); Zillmann, B.; Lampke, T. [Institute of Materials Science and Engineering, Chemnitz University of Technology, Erfenschlager Strasse 73 D-09125 Chemnitz (Germany)

    2013-12-16T23:59:59.000Z

    A main problem in the field of sheet metal characterization is the inhomogeneous plastic deformation in the gauge regions of specimens which causes the analytically calculated stresses to differ from the sought state of stress acting in the middle of the gauge region. To overcome this problem, application of X-Ray diffraction is analyzed. For that purpose a mobile X-ray diffractometer and an optical strain measurement system are mounted on a universal tensile testing machine. This enables the recording of the whole strain and stress history of a material point. The method is applied to uniaxial tension tests, plane strain tension tests and shear tests to characterize the interstitial free steel alloy DC06. The applicability of the concepts of stress factors is verified by uniaxial tension tests. The experimentally obtained values are compared with the theoretical values calculated with crystal elasticity models utilizing the orientation distribution functions (ODF). The relaxation problem is addressed which shows itself as drops in the stress values with the strain kept at a constant level. This drop is analyzed with elasto-viscoplastic material models to correct the measured stresses. Results show that the XRD is applicable to measure the stresses in sheet metals with preferred orientation. The obtained yield locus is expressed with the Yld2000–2D material model and an industry oriented workpiece is analyzed numerically. The comparison of the strain distribution on the workpiece verifies the identified material parameters.

  7. Absolute x-ray energy calibration over a wide energy range using a diffraction-based iterative method

    E-Print Network [OSTI]

    Duffy, Thomas S.

    Mineral Physics Institute, Stony Brook University, Stony Brook, New York 11794, USA 2 DepartmentAbsolute x-ray energy calibration over a wide energy range using a diffraction-based iterative;REVIEW OF SCIENTIFIC INSTRUMENTS 83, 063901 (2012) Absolute x-ray energy calibration over a wide energy

  8. Data preparation and evaluation techniques for x-ray diffraction microscopy

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Steinbrener, Jan; Nelson, Johanna; Huang, Xiaojing; Marchesini, Stefano; Shapiro, David; Turner, Joshua J.; Jacobsen, Chris

    2010-01-01T23:59:59.000Z

    The post-experiment processing of X-ray Diffraction Microscopy data is often time-consuming and difficult. This is mostly due to the fact that even if a preliminary result has been reconstructed, there is no definitive answer as to whether or not a better result with more consistently retrieved phases can still be obtained. We show here that the first step in data analysis, the assembly of two-dimensional diffraction patterns from a large set of raw diffraction data, is crucial to obtaining reconstructions of highest possible consistency. We have developed software that automates this process and results in consistently accurate diffraction patterns. Wemore »have furthermore derived some criteria of validity for a tool commonly used to assess the consistency of reconstructions, the phase retrieval transfer function, and suggest a modified version that has improved utility for judging reconstruction quality.« less

  9. Data preparation and evaluation techniques for x-ray diffraction microscopy

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Steinbrener, Jan; Nelson, Johanna; Huang, Xiaojing; Marchesini, Stefano; Shapiro, David; Turner, Joshua J.; Jacobsen, Chris

    2010-01-01T23:59:59.000Z

    The post-experiment processing of X-ray Diffraction Microscopy data is often time-consuming and difficult. This is mostly due to the fact that even if a preliminary result has been reconstructed, there is no definitive answer as to whether or not a better result with more consistently retrieved phases can still be obtained. We show here that the first step in data analysis, the assembly of two-dimensional diffraction patterns from a large set of raw diffraction data, is crucial to obtaining reconstructions of highest possible consistency. We have developed software that automates this process and results in consistently accurate diffraction patterns. We have furthermore derived some criteria of validity for a tool commonly used to assess the consistency of reconstructions, the phase retrieval transfer function, and suggest a modified version that has improved utility for judging reconstruction quality.

  10. Automated high pressure cell for pressure jump x-ray diffraction

    SciTech Connect (OSTI)

    Brooks, Nicholas J.; Gauthe, Beatrice L. L. E.; Templer, Richard H.; Ces, Oscar; Seddon, John M. [Department of Chemistry, Imperial College London, South Kensington Campus, London SW7 2AZ (United Kingdom); Terrill, Nick J. [Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE (United Kingdom); Rogers, Sarah E. [ISIS, Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0QX (United Kingdom)

    2010-06-15T23:59:59.000Z

    A high pressure cell for small and wide-angle x-ray diffraction measurements of soft condensed matter samples has been developed, incorporating a fully automated pressure generating network. The system allows both static and pressure jump measurements in the range of 0.1-500 MPa. Pressure jumps can be performed as quickly as 5 ms, both with increasing and decreasing pressures. Pressure is generated by a motorized high pressure pump, and the system is controlled remotely via a graphical user interface to allow operation by a broad user base, many of whom may have little previous experience of high pressure technology. Samples are loaded through a dedicated port allowing the x-ray windows to remain in place throughout an experiment; this facilitates accurate subtraction of background scattering. The system has been designed specifically for use at beamline I22 at the Diamond Light Source, United Kingdom, and has been fully integrated with the I22 beamline control systems.

  11. Time-, frequency-, and wavevector-resolved x-ray diffraction from single molecules

    SciTech Connect (OSTI)

    Bennett, Kochise, E-mail: kcbennet@uci.edu; Biggs, Jason D.; Zhang, Yu; Dorfman, Konstantin E.; Mukamel, Shaul, E-mail: smukamel@uci.edu [University of California, Irvine, California 92697-2025 (United States)

    2014-05-28T23:59:59.000Z

    Using a quantum electrodynamic framework, we calculate the off-resonant scattering of a broadband X-ray pulse from a sample initially prepared in an arbitrary superposition of electronic states. The signal consists of single-particle (incoherent) and two-particle (coherent) contributions that carry different particle form factors that involve different material transitions. Single-molecule experiments involving incoherent scattering are more influenced by inelastic processes compared to bulk measurements. The conditions under which the technique directly measures charge densities (and can be considered as diffraction) as opposed to correlation functions of the charge-density are specified. The results are illustrated with time- and wavevector-resolved signals from a single amino acid molecule (cysteine) following an impulsive excitation by a stimulated X-ray Raman process resonant with the sulfur K-edge. Our theory and simulations can guide future experimental studies on the structures of nano-particles and proteins.

  12. High-Angular-Resolution Microbeam X-Ray Diffraction with CCD Detector

    SciTech Connect (OSTI)

    Imai, Yasuhiko; Kimura, Shigeru; Sakaia, Akira [Japan Synchrotron Radiation Research Institute, SPring-8, 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5198 (Japan); Sakata, Osami [Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama-cho, Toyonaka, Osaka 670-8531 (Japan)

    2010-04-06T23:59:59.000Z

    We have introduced a CCD-type two-dimensional X-ray detector for a microbeam X-ray diffraction system using synchrotron radiation, so that we can measure local reciprocal space maps (RSM) of samples rapidly. A local RSM of a strain-relaxed SiGe 004 grown on a Si (001) substrate was measured in higher-angular-resolution and faster than a conventional way. The measurement was achieved in 1 h 40 min. with the 2theta resolution of 80 murad and the spatial resolution of 1.4(h)x0.5(v) {mu}m{sup 2}. The introduction of the CCD enabled us to measure RSMs at many points in a sample, that is, the distribution of strain fields and lattice tilts can be revealed in high-angular- and high-spatial-resolution.

  13. Fixture for supporting and aligning a sample to be analyzed in an x-ray diffraction apparatus

    DOE Patents [OSTI]

    Green, L.A.; Heck, J.L. Jr.

    1985-04-23T23:59:59.000Z

    A fixture is provided for supporting and aligning small samples of material on a goniometer for x-ray diffraction analysis. A sample-containing capillary is accurately positioned for rotation in the x-ray beam by selectively adjusting the fixture to position the capillary relative to the x and y axes thereof to prevent wobble and position the sample along the z axis or the axis of rotation. By employing the subject fixture relatively small samples of materials can be analyzed in an x-ray diffraction apparatus previously limited to the analysis of much larger samples.

  14. Study of microstress state of P91 steel using complementary mechanical Barkhausen, magnetoacoustic emission, and X-ray diffraction techniques

    SciTech Connect (OSTI)

    Augustyniak, Boles?aw, E-mail: bolek@mif.pg.gda.pl; Piotrowski, Leszek; Maciakowski, Pawe?; Chmielewski, Marek [Faculty of Applied Physics and Mathematics, Gdansk University of Technology, 80-233 Gdansk (Poland); Lech-Grega, Marzena; ?elechowski, Janusz [The Institute of Non-Ferrous Metals, 32-050 Skawina (Poland)

    2014-05-07T23:59:59.000Z

    The paper deals with assessment of microstress state of martensite P91 steel using three complementary techniques: mechanical Barkhausen emission, magnetoacoustic emission (MAE), and X-ray diffraction (XRD) profile analysis. Magnetic coercivity Hc and microstructure were investigated with inductive magnetometry and magnetic force microscopy (MFM), respectively. Internal stress level of P91 steel was modified by heat treatment. Steel samples were austenitized, quenched, and then tempered at three temperatures (720?°C, 750?°C, and 780?°C) during increasing time (from 15?min up to 240?min). The microstrain level ?{sub i} was evaluated using Williamson–Hall method. It was revealed that during tempering microstrain systematically decreases from ?{sub i}?=?2.5 × 10{sup ?3} for as quenched state down to ?{sub i}?=?0.3?×?10{sup ?3} for well tempered samples. Both mechanical hardness (Vicker's HV) and magnetic hardness (coercivity) decrease almost linearly with decreasing microstrain while the MAE and MBE intensities strongly increase. Tempering leads to evident shift of the MeBN intensity maximum recorded for the first load towards lower applied strain values and to increase of MAE intensity. This indicates that the microstress state deduced by magnetic techniques is correlated with microstrains evaluated with XRD technique.

  15. Development of an adaptable coherent x-ray diffraction microscope with the emphasis on imaging hydrated specimens

    SciTech Connect (OSTI)

    Nam, Daewoong [RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo, Hyogo 679-5148 (Japan) [RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo, Hyogo 679-5148 (Japan); Department of Physics, Pohang University of Science and Technology, Pohang 790-784 (Korea, Republic of); Park, Jaehyun; Shimada, Hiroki; Kim, Sangsoo; Kim, Sunam; Kohmura, Yoshiki; Ishikawa, Tetsuya; Song, Changyong [RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo, Hyogo 679-5148 (Japan)] [RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo, Hyogo 679-5148 (Japan); Gallagher-Jones, Marcus [RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo, Hyogo 679-5148 (Japan) [RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo, Hyogo 679-5148 (Japan); Institute of Integrative Biology, University of Liverpool, Liverpool L69 7ZB (United Kingdom)

    2013-11-15T23:59:59.000Z

    This paper describes the development of a versatile coherent x-ray diffraction microscope capable of imaging biological specimens in solution. The microscope is a flexible platform accommodating various conditions, from low vacuum (10{sup ?2} Pa) to helium gas filled ambient pressure. This flexibility greatly expands the application area, from in situ materials science to biology systems in their native state, by significantly relaxing restrictions to the sample environment. The coherent diffraction microscope has been used successfully to image a yeast cell immersed in buffer solution. We believe that the design of this coherent diffraction microscope can be directly adapted to various platforms such as table top soft x-ray laser, synchrotron x-ray sources, and x-ray free electron laser with minor relevant adjustments.

  16. High resolution x-ray and gamma ray imaging using diffraction lenses with mechanically bent crystals

    DOE Patents [OSTI]

    Smither, Robert K. (Hinsdale, IL)

    2008-12-23T23:59:59.000Z

    A method for high spatial resolution imaging of a plurality of sources of x-ray and gamma-ray radiation is provided. High quality mechanically bent diffracting crystals of 0.1 mm radial width are used for focusing the radiation and directing the radiation to an array of detectors which is used for analyzing their addition to collect data as to the location of the source of radiation. A computer is used for converting the data to an image. The invention also provides for the use of a multi-component high resolution detector array and for narrow source and detector apertures.

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

    SciTech Connect (OSTI)

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

    2011-12-31T23:59:59.000Z

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

  18. X-Ray Diffraction (XRD) At Long Valley Caldera Geothermal Area...

    Open Energy Info (EERE)

    studies, and seem to prove useful in most cases (Flexser, 1991; Goff et al., 1991; Smith and Suemnicht, 1991). Results from these studies are also summarized in Sorey et al....

  19. X-Ray Diffraction (XRD) At Long Valley Caldera Geothermal Area (Flexser,

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov YouKizildere IRaghuraji Agro IndustriesTownDells, Wisconsin: EnergyWyandanch, New York:State ParksWyrulec1991) | Open

  20. Mechanics of Microelectronics Structures as Revealed by X-ray Diffraction

    SciTech Connect (OSTI)

    Murray,C.; Yan, H.; Noyan, I.

    2007-01-01T23:59:59.000Z

    The presence of strain distributions within semiconductor features influences many aspects of their behavior. For example, microelectronic technology that incorporates strained silicon improves device performance by increasing carrier mobility in the Si channels. Because current semiconductor fabrication contains multiple levels of metallic and dielectric structures, an understanding of the mechanical response of the constituent elements is critical to the prediction of the overall device performance. In addition, the interaction of strain fields between adjacent structures becomes greater as feature sizes decrease and the corresponding feature density increases. The use of synchrotron-based X-ray methods allows one to determine the interaction between strained features and their environment at a submicron resolution. Real-space mapping of strain distributions in pseudomorphically strained, raised SiGe structures revealed that elastic relaxation extends approximately 20 times the feature thickness from their edges. X-ray topographic methods were also applied to map the substrate deformation induced by overlying SiGe features. A formulation based on the classical Ewald-von Laue theory of dynamical diffraction was derived to match the measured diffraction profiles.

  1. High-pressure powder x-ray diffraction study of EuVO4

    E-Print Network [OSTI]

    Garg, Alka B

    2015-01-01T23:59:59.000Z

    The high-pressure structural behavior of europium orthovanadate has been studied using in-situ, synchrotron based, high-pressure x-ray powder diffraction technique. Angle-dispersive x-ray diffraction measurements were carried out at room temperature up to 34.7 GPa using a diamond-anvil cell, extending the pressure range reported in previous experiments. We confirmed the occurrence of zircon-scheelite phase transition at 6.8 GPa and the coexistence of low- and high-pressure phases up to 10.1 GPa. In addition, clear evidence of a scheelite-fregusonite transition is found at 23.4 GPa. The fergusonite structure remains stable up to 34.7 GPa, the highest pressure reached in the present measurements. A partial decomposition of EuVO4 was also observed from 8.1 to 12.8 GPa, however, this fact did not preclude the identification of the different crystal structures of EuVO4. The crystal structures of the different phases have been Rietveld refined and their equations of state (EOS) have been determined. The results are...

  2. First results from a next-generation off-plane X-ray diffraction grating

    E-Print Network [OSTI]

    McEntaffer, Randall; Schultz, Ted; Gantner, Brennan; Tutt, James; Holland, Andrew; O'Dell, Stephen; Gaskin, Jessica; Kolodziejczak, Jeffrey; Zhang, William W; Chan, Kai-Wing; Biskach, Michael; McClelland, Ryan; Iazikov, Dmitri; Wang, Xinpeng; Koecher, Larry

    2013-01-01T23:59:59.000Z

    Future NASA X-ray spectroscopy missions will require high throughput, high resolution grating spectrometers. Off-plane reflection gratings are capable of meeting the performance requirements needed to realize the scientific goals of these missions. We have identified a novel grating fabrication method that utilizes common lithographic and microfabrication techniques to produce the high fidelity groove profile necessary to achieve this performance. Application of this process has produced an initial pre-master that exhibits a radial (variable line spacing along the groove dimension), high density (>6000 grooves/mm), laminar profile. This pre-master has been tested for diffraction efficiency at the BESSY II synchrotron light facility and diffracts up to 55% of incident light into usable spectral orders. Furthermore, tests of spectral resolving power show that these gratings are capable of obtaining resolutions well above 1300 ($\\lambda/\\Delta\\lambda$) with limitations due to the test apparatus, not the gratings...

  3. High-pressure X-ray diffraction and X-ray emission studies on iron-bearing silicate perovskite under high pressures

    SciTech Connect (OSTI)

    Lin, Jung-Fu; Speciale, Sergio; Prakapenka, Vitali B.; Dera, Przemek; Lavina, Babara; Watson, Heather C. (NIU); (UC); (Texas); (GFZ)

    2010-06-22T23:59:59.000Z

    Iron-bearing silicate perovskite is believed to be the most abundant mineral of the Earth's lower mantle. Recent studies have shown that Fe{sup 2+} exists predominantly in the intermediate-spin state with a total spin number of 1 in silicate perovskite in the lower part of the lower mantle. Here we have measured the spin states of iron and the pressure-volume relation in silicate perovskite [(Mg{sub 0.6},Fe{sub 0.4})SiO{sub 3}] at pressure conditions relevant to the lowermost mantle using in situ X-ray emission and X-ray diffraction in a diamond cell. Our results showed that the intermediate-spin Fe{sup 2+} is stable in the silicate perovskite up to {approx} 125 GPa but starts to transition to the low-spin state at approximately 135 GPa. Concurrent X-ray diffraction measurements showed a decrease of approximately 1% in the unit cell volume in the silicate perovskite [(Mg{sub 0.6},Fe{sub 0.4})SiO{sub 3}], which is attributed to the intermediate-spin to the low-spin transition. The transition pressure coincides with the pressure conditions of the lowermost mantle, raising the possibility of the existence of the silicate perovskite phase with the low-spin Fe{sup 2+} across the transition from the post-perovskite to the perovskite phases in the bottom of the D{double_prime} layer.

  4. Crystal structures of N sub 2 O to 12 GPa by x-ray diffraction

    SciTech Connect (OSTI)

    Mills, R.L.; Olinger, B.; Cromer, D.T.; LeSar, R. (University of California, Los Alamos National Laboratory, Los Alamos, New Mexico (USA))

    1991-10-01T23:59:59.000Z

    The structures and phase transitions of N{sub 2}O were studied by powder x-ray diffraction in a tungsten--carbide anvil device from about 100 to 300 K and 2 to 12 GPa. Two solid phases, {alpha}-N{sub 2}O and {beta}-N{sub 2}O, were observed. The {alpha} pattern is consistent with the known low-pressure low-temperature ordered cubic form, space group Pa3, up to 4.8 GPa where transition to a new {beta} solid occurs. From refinements using photographic x-ray intensities, the {beta}-N{sub 2}O structure was determined to be orthorhombic Cmca. There are four molecules in a unit cell with {ital a}=4.954 A, {ital b}=4.497 A, and {ital c}=6.201 A at 5.81 GPa and 298 K. The molecular axes lie parallel to the {ital bc} plane and are tipped at an angle of 37.2{degree} to the {ital b} axis. Random head-to-tail orientation is probable in both solids. The phase diagram and values of the molar volume for N{sub 2}O are compared with published data for the isoelectronic molecule CO{sub 2}. Recent theoretical calculations correctly predict the {beta}-N{sub 2}O structure.

  5. High-temperature/high-pressure x-ray diffraction: Recent developments

    SciTech Connect (OSTI)

    Schiferl, D.; Johnson, S.W.; Zinn, A.S.

    1989-01-01T23:59:59.000Z

    We have developed two Merrill-Bassett diamond-anvil cells for specialized high-temperature uses. The first is constructed largely of rhenium to provide uniform, constant P and T on the order of 20 GPa at 1200 K for extended periods. The second is for single-crystal x-ray diffraction, but can be heated to 630 K at 20 GPa to grow single-crystal samples which cannot be produced at room temperature. With this cell, the crystal structure of /var epsilon/-O/sub 2/ was shown to be monoclinic with a = 3.649 A, b = 5.493 A, c = 7.701 A, and /Beta/ = 116.11/degree/ at 19.7 GPa. 15 refs.

  6. Kinetics of Methane Hydrate Decomposition Studied via in Situ Low Temperature X-ray Powder Diffraction

    SciTech Connect (OSTI)

    Everett, Susan M [ORNL; Rawn, Claudia J [ORNL; Keffer, David J. [University of Tennessee, Knoxville (UTK); Mull, Derek L [ORNL; Payzant, E Andrew [ORNL; Phelps, Tommy Joe [ORNL

    2013-01-01T23:59:59.000Z

    Gas hydrates are known to have a slowed decomposition rate at ambient pressure and temperatures below the melting point of ice termed self-preservation or anomalous preservation. As hydrate exothermically decomposes, gas is released and water of the clathrate cages transforms into ice. Two regions of slowed decomposition for methane hydrate, 180 200 K and 230 260 K, were observed, and the kinetics were studied by in situ low temperature x-ray powder diffraction. The kinetic constants for ice formation from methane hydrate were determined by the Avrami model within each region and activation energies, Ea, were determined by the Arrhenius plot. Ea determined from the data for 180 200 K was 42 kJ/mol and for 230 260 K was 22 kJ/mol. The higher Ea in the colder temperature range was attributed to a difference in the microstructure of ice between the two regions.

  7. High-pressure behavior and thermoelastic properties of niobium studied by in situ x-ray diffraction

    SciTech Connect (OSTI)

    Zou, Yongtao, E-mail: yongtao.zou@stonybrook.edu, E-mail: yongtaozou6@gmail.com; Li, Baosheng [Mineral Physics Institute, State University of New York, Stony Brook, New York 11794 (United States); Qi, Xintong [Department of Materials Science and Engineering, State University of New York, Stony Brook, New York 11794 (United States); Wang, Xuebing; Chen, Ting [Department of Geosciences, State University of New York, Stony Brook, New York 11794 (United States); Li, Xuefei [Mineral Physics Institute, State University of New York, Stony Brook, New York 11794 (United States); Key Laboratory of Functional Materials Physics and Chemistry of the Ministry of Education, Jilin Normal University, Siping 136000 (China); Welch, David [Department of Materials Science and Engineering, State University of New York, Stony Brook, New York 11794 (United States); Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, New York 11973 (United States)

    2014-07-07T23:59:59.000Z

    In situ synchrotron energy dispersive x-ray diffraction (XRD) experiments on Nb have been conducted at pressures up to 6.4 GPa and temperatures up to 1073 K. From the pressure-volume-temperature measurements, thermoelastic parameters were derived for the first time for Nb based on the thermal pressure (?P{sub th}) equation of state (EOS), modified high-T Birch-Murnaghan EOS, and Mie-Grüneisen-Debye EOS. With the pressure derivative of the bulk modulus K{sub T}{sup ´} fixed at 4.0, we obtained the ambient isothermal bulk modulus K{sub T0}=174(5) GPa, the temperature derivative of bulk modulus at constant pressure (?K{sub T}/?T){sub P}=-0.060(8) GPa K?¹ and at constant volume (?K{sub T}/?T){sub V}=-0.046(8) GPa K?¹, the volumetric thermal expansivity ?{sub T}(T)=2.3(3)×10??+0.3(2)×10??T (K?¹), as well as the pressure dependence of thermal expansion (??/?P){sub T}=(?2.0±0.4)×10?? K?¹ GPa?¹. Fitting the present data to the Mie-Grüneisen-Debye EOS with Debye temperature ??=276.6 K gives ??=1.27(8) and K{sub T0}=171(3) GPa at a fixed value of q=3.0. The ambient isothermal bulk modulus and Grüneisen parameter derived from this work are comparable to previously reported values from both experimental and theoretical studies. An in situ high-resolution, angle dispersive XRD study on Nb did not indicate any anomalous behavior related to pressure-induced electronic topological transitions at ~5 GPa as has been reported previously.

  8. A wavelet transform algorithm for peak detection and application to powder x-ray diffraction data

    SciTech Connect (OSTI)

    Gregoire, John M.; Dale, Darren; van Dover, R. Bruce

    2011-01-01T23:59:59.000Z

    Peak detection is ubiquitous in the analysis of spectral data. While many noise-filtering algorithms and peak identification algorithms have been developed, recent work [P. Du, W. Kibbe, and S. Lin, Bioinformatics 22, 2059 (2006); A. Wee, D. Grayden, Y. Zhu, K. Petkovic-Duran, and D. Smith, Electrophoresis 29, 4215 (2008)] has demonstrated that both of these tasks are efficiently performed through analysis of the wavelet transform of the data. In this paper, we present a wavelet-based peak detection algorithm with user-defined parameters that can be readily applied to the application of any spectral data. Particular attention is given to the algorithm's resolution of overlapping peaks. The algorithm is implemented for the analysis of powder diffraction data, and successful detection of Bragg peaks is demonstrated for both low signal-to-noise data from theta–theta diffraction of nanoparticles and combinatorial x-ray diffraction data from a composition spread thin film. These datasets have different types of background signals which are effectively removed in the wavelet-based method, and the results demonstrate that the algorithm provides a robust method for automated peak detection.

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

    SciTech Connect (OSTI)

    Buergi, J.; Molleja, J. Garcia; Feugeas, J. [Instituto de Fisica Rosario (CONICET-UNR), Bv. 27 de Febrero 210 bis, S2000EZP Rosario (Argentina); Neuenschwander, R. [Laboratorio Nacional Luz Sincrotron (LNLS), Caixa Postal 6192, CEP13083-970 Campinas (Brazil); Kellermann, G. [Departamento de Fisica (Universidade Federal do Parana), Caixa Postal 19044, CEP81531-990 Curitiba (Brazil); Craievich, A. F. [Instituto de Fisica (Universidade de Sao Paulo), Rua do Matao Travessa R 187, CEP05508-090 Sao Paulo (Brazil)

    2013-01-15T23:59:59.000Z

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

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

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Lyubimov, Artem Y.; Murray, Thomas D.; Koehl, Antoine; Araci, Ismail Emre; Uervirojnangkoorn, Monarin; Zeldin, Oliver B.; Cohen, Aina E.; Soltis, S. Michael; Baxter, Elizabeth L.; Brewster, Aaron S.; et al

    2015-04-01T23:59:59.000Z

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

  11. Mossbauer spectroscopic and x-ray diffraction studies of FeSiO2 nanocomposite soft magnetic materials

    E-Print Network [OSTI]

    Yang, De-Ping

    Mo¨ssbauer spectroscopic and x-ray diffraction studies of FeÕSiO2 nanocomposite soft magnetic. The compositions of the precursor and the successive heat-treated samples have been investigated by 57 Fe Mo¨ssbauer a synthesis of Fe/SiO2 nanocomposites and a study of their magnetic and structural properties using Mo¨ssbauer

  12. X-ray diffraction studies and equation of state of methane at 202 GPa Liling Sun a,*, Wei Yi a

    E-Print Network [OSTI]

    Shen, Guoyin

    X-ray diffraction studies and equation of state of methane at 202 GPa Liling Sun a,*, Wei Yi that at room temperature compressed CH4 remains an insulator with cubic structure to 202 GPa. Ó 2009 Elsevier B of planetary interiors and the origin of their magnetic field distribution. CH4 has a very rich phase diagram

  13. High temperature x ray diffraction determination of the body-centered-cubicface-centered-cubic transformation temperature in

    E-Print Network [OSTI]

    McHenry, Michael E.

    , generators, transformers, sensors,1 and, more recently, for magnetic refrigeration.4­6 Recently 16 February 2012) In situ high-temperature x ray diffraction and magnetization measurements were.1063/1.3675990] INTRODUCTION Fe-Ni alloys have been extensively studied, due to their technologically important magnetic

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

    E-Print Network [OSTI]

    van Vliet, Lucas J.

    In-line x-ray phase-contrast tomography and diffraction-contrast tomography study of the ferrite;In-line X-ray phase-contrast tomography and diffraction-contrast tomography study of the ferrite embedded in a ferrite matrix of medium-carbon steel. The measurements were carried out at the material

  15. Blazed high-efficiency x-ray diffraction via transmission through arrays of

    E-Print Network [OSTI]

    with the x-ray microscope at BESSY," Rev. Sci. Instrum. 66, 1282-1286 (1995). 12. A. G. Klein and S. A

  16. A combined solid-state NMR and synchrotron x-ray diffraction powder study on the structure of the antioxidant(+)-catechin 4.5 hydrate.

    SciTech Connect (OSTI)

    Harper, J. K.; Doebbler, J. A.; Jaccques, E.; Grant, D. M.; Von Dreele, R. B.; Univ. of Utah

    2010-03-10T23:59:59.000Z

    Analyses combining X-ray powder diffraction (XRD) and solid-state NMR (SSNMR) data can now provide crystal structures in challenging powders that are inaccessible by traditional methods. The flavonoid catechin is an ideal candidate for these methods, as it has eluded crystallographic characterization despite extensive study. Catechin was first described nearly two centuries ago, and its powders exhibit numerous levels of hydration. Here, synchrotron XRD data provide all heavy-atom positions in (+)-catechin 4.5-hydrate and establish the space group as C2. SSNMR data ({sup 13}C tensor and {sup 1}H/{sup 13}C correlation) complete the conformation by providing catechin's five OH hydrogen orientations. Since 1903, this phase has been erroneously identified as a 4.0 hydrate, but XRD and density data establish that this discrepancy is due to the facile loss of the water molecule located at a Wyckoff special position in the unit cell. A final improvement to heavy-atom positions is provided by a geometry optimization of bond lengths and valence angles with XRD torsion angles held constant. The structural enhancement in this final structure is confirmed by the significantly improved fit of computed {sup 13}C tensors to experimental data.

  17. Analysis of X-Ray Diffraction as a Probe of Interdiffusion in Si/SiGe Heterostructures

    SciTech Connect (OSTI)

    Brennan, Sean M

    2003-08-20T23:59:59.000Z

    We investigate numerical simulations that utilize a non-linear interdiffusion solver and dynamical x-ray diffraction calculations to predict the local composition evolution in low Ge concentration Si/SiGe superlattices and their diffraction patterns during annealing. Superlattice satellite peak decay rates are compared with experimentally measured values and simulated diffraction patterns are matched directly to data with good success. The simulations are used to test the sensitivity of x-ray diffraction to various uncertainties commonly encountered when measuring interdiffusion at Si/SiGe interfaces. It is found that the most serious errors result from variations in the Ge content across the surface of the wafer. For example, the resolution limit of most experimental techniques used to measure Ge concentration in a SiGe film is -1 at.%, for a film with 11% mean Ge concentration annealed for 5 hours at 870 C, this level of error will cause the observed interdiffusivity values to deviate by -25% or +50%. The simulations are further used to show that for Si/SiGe interdiffusion, superlattice diffraction produces valid measurements when applied to 004 superlattice satellite peaks and square wave composition modulations even though it is only exactly applicable to satellite peaks about 000 reflection and to sinusoidal composition modulations. Finally, we show that proper interpretation of x-ray scattering data to extract Si/SiGe interdiffusivity values must account for the strong dependence of the interdiffusivity on Ge concentration.

  18. Simultaneous probing of phase transformations in Ni-Ti thin film shape memory alloy by synchrotron radiation-based X-ray diffraction and electrical resistivity

    SciTech Connect (OSTI)

    Braz Fernandes, F.M. [CENIMAT/I3N, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica (Portugal); Mahesh, K.K., E-mail: kkmahesh@rediffmail.com [CENIMAT/I3N, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica (Portugal); Martins, R.M.S. [CENIMAT/I3N, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica (Portugal); Institute of Ion Beam Physics and Materials Research, Helmholtz-Zentrum Dresden-Rossendorf (HZDR), P.O. Box 510119, 01314 Dresden (Germany); IST/Instituto Tecnológico e Nuclear (IST/ITN), Universidade Técnica de Lisboa, EN10, 2696-953 Sacavém (Portugal); Centro de Física Nuclear da Universidade de Lisboa (CFNUL), Av. Prof. Gama Pinto 2, 1649-003 Lisboa (Portugal); Silva, R.J.C. [CENIMAT/I3N, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica (Portugal); Baehtz, C.; Borany, J. von [Institute of Ion Beam Physics and Materials Research, Helmholtz-Zentrum Dresden-Rossendorf (HZDR), P.O. Box 510119, 01314 Dresden (Germany)

    2013-02-15T23:59:59.000Z

    Nickel–Titanium (Ni–Ti) thin film shape memory alloys (SMAs) have been widely projected as novel materials which can be utilized in microdevices. Characterization of their physical properties and its correlation with phase transformations has been a challenging issue. In the present study, X-ray beam diffraction has been utilized to obtain the structural information at different temperatures while cooling. Simultaneously, electrical resistivity (ER) was measured in the phase transformation temperature range. The variation of ER and integral area of the individual diffraction peaks of the different phases as a function of temperature have been compared. A mismatch between the conventional interpretation of ER variation and the results of the XRD data has been clearly identified. - Highlights: ? Phase transformation characterization of Ni–Ti thin film SMA has been carried out. ? Simultaneous monitoring of the XRD and ER with temperature is performed. ? The variation of ER and integral area of the diffraction peaks have been compared. ? A shift of the transformation temperatures obtained by two techniques is discussed.

  19. Rietveld X-ray diffraction analysis of nanostructured rutile films of titania prepared by pulsed laser deposition

    SciTech Connect (OSTI)

    Murugesan, S. [Physical Metallurgy Division, Indira Gandhi Centre for Atomic Research, Kalpakkam 603102, Tamil Nadu (India)] [Physical Metallurgy Division, Indira Gandhi Centre for Atomic Research, Kalpakkam 603102, Tamil Nadu (India); Kuppusami, P., E-mail: pk@igcar.gov.in [Physical Metallurgy Division, Indira Gandhi Centre for Atomic Research, Kalpakkam 603102, Tamil Nadu (India); Mohandas, E. [Physical Metallurgy Division, Indira Gandhi Centre for Atomic Research, Kalpakkam 603102, Tamil Nadu (India)] [Physical Metallurgy Division, Indira Gandhi Centre for Atomic Research, Kalpakkam 603102, Tamil Nadu (India)

    2010-01-15T23:59:59.000Z

    Rietveld powder X-ray diffraction analysis of the rutile films of titanium oxide prepared by pulsed laser deposition was carried out. The crystallite size increased with increase of substrate temperature, while the strain showed a reverse trend. The films synthesized at temperature {>=}573 K showed that the crystal structure was almost close to that of bulk rutile structure. The influence of the substrate temperature on the lattice parameters and oxygen coordinates were also studied in the present work.

  20. anomalous x-ray diffraction: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    from the soft X-rays emitted by the neutron-star surface. The relation between these heating rates and measured near-infrared fluxes in the K and Ks bands places severe...

  1. X-ray Diffraction Laboratory: Department of Chemistry Texas A & M University

    E-Print Network [OSTI]

    Meagher, Mary

    and the data containing computers will not be connected by wired or wireless internet networks to the Word Wide Web. RESPONSIBILITY: The X-ray Laboratory personell will be responsible for security issues. MATERIALS

  2. Characterization of montmorillonite doped PVA/SA blends using X-ray diffraction

    SciTech Connect (OSTI)

    Hemalatha, K.; Somashekarappa, H. [Department of Physics, Yuvaraja's College, University of Mysore, Manasagangotri, Mysore-570005 (India); Mahadevaiah,; Somashekar, R., E-mail: rs@physics.uni-mysore.ac.in [Department of Studies in Physics, University of Mysore, Manasagangotri, Mysore-570006 (India)

    2014-04-24T23:59:59.000Z

    PVA films doped with Montmorillonite was prepared by slow evaporation technique. These films have been used to record X-ray patterns at room temperature. Correlation lengths and microstructural parameters were computed using in-house program employing X-ray data. Results show that correlation lengths as well as crystallite size increases with increase in the concentration of Montmorillonite which is inconformity with the conductivity studies.

  3. Investigation of the spontaneous lateral modulation in short-period superlattices by grazing-incidence x-ray diffraction.

    SciTech Connect (OSTI)

    Moss, Simon C. (University of Houston, Houston, TX); Holy, Vaclav (Charles University, Prague, Czech Republic); Reno, John Louis; Krause, B. (ESRF, Grenoble, France); Norman, Andrew G. (National Renewable Energy Laboratory, Golden, CO); Mikulik, P. (Masaryk University, Brno, Czech Republic); Caha, O. (Masaryk University, Brno, Czech Republic); Mascarenhas, Angelo (National Renewable Energy Laboratory, Golden, CO)

    2005-03-01T23:59:59.000Z

    The process of spontaneous lateral composition modulation in short-period InAs/AlAs superlattices has been investigated by grazing-incidence x-ray diffraction. We have developed a theoretical description of x-ray scattering from laterally modulated structures that makes it possible to determine the lateral composition modulation directly without assuming any structure model. From experimental intensity distributions in reciprocal space we have determined the amplitudes of the modulation and its degree of periodicity and their dependence on the number of superlattice periods. From the data it follows that the modulation process cannot be explained by bunching of monolayer steps and most likely, it is caused by stress-driven morphological instabilities of the growing surface.

  4. Structures and transitions in solid O/sub 2/ to 13 GPa at 298 K by x-ray diffraction

    SciTech Connect (OSTI)

    Olinger, B.; Mills, R.L.; Roof R.B. Jr.

    1984-12-01T23:59:59.000Z

    The structures and phase transitions in solid O/sub 2/ were studied at 298 K from 6 to 13 GPa using powder x-ray diffraction in an anvil cell. Pressures were determined from the compression of in situ NaF. X-ray photographs at various pressures showed patterns from five different phases of O/sub 2/, two of which were previously unreported. Values of the bulk modulus and volume were derived up to 11 GPa where transition to epsilon-O/sub 2/ occurs. A compromise fit to all available data indicates that epsilon-O/sub 2/ may be an orthorhombic distortion of delta-O/sub 2/.

  5. Design and imaging performance of achromatic diffractive/refractive X-ray and Gamma-ray Fresnel lenses

    E-Print Network [OSTI]

    Gerald K. Skinner

    2004-07-21T23:59:59.000Z

    Achromatic combinations of a diffractive Phase Fresnel Lens and a refractive correcting element have been proposed for X-ray and gamma-ray astronomy and for microlithography, but considerations of absorption often dictate that the refractive component be given a stepped profile, resulting in a double Fresnel lens. The imaging performance of corrected Fresnel lenses, with and without `stepping' is investigated and the trade-off between resolution and useful bandwidth in different circumstances is discussed. Provided the focal ratio is large, correction lenses made of low atomic number materials can be used with X-rays in the range approximately 10--100 keV without stepping. The use of stepping extends the possibility of correction to higher aperture systems, to energies as low as a few kilo electron volts and to gamma-rays of $\\sim$ mega electron volt energy.

  6. X-ray diffraction, spectroscopic and DFT studies of 1-(4-bromophenyl)-3,5-diphenylformazan

    SciTech Connect (OSTI)

    Tezcan, H., E-mail: habibe@gazi.edu.tr [Gazi University, Department of Chemistry, Faculty of Education (Turkey); Tokay, N. [Hacettepe University, Department of Chemistry, Faculty of Science (Turkey); Alpaslan, G. [Giresun University, Department of Medical Services and Techniques, Vocational School of Health Services (Turkey); Erdönmez, A. [Ondokuz May?s University, Department of Physics, Faculty of Science and Art (Turkey)

    2013-12-15T23:59:59.000Z

    The crystal structure of 1-(4-bromophenyl)-3,5-diphenylformazan was determined by X-ray single crystal diffraction technique. The crystals are orthorhombic, a = 23.0788(9), b = 7.9606(3), c = 18.6340(12) Å, Z = 8, sp. gr. Pbca, R{sub 1} = 0.074. The structure was also examined using the density-functional theory. Its structure stability, and frontier molecular orbital components were discussed and the results were compared with X-ray and spectral results. The maximum absorbtion peaks of the UV-vis spectrum of the compound have been calculated using the time-dependent density-functional theory. It was found a good agreement between the calculated and experimental maximum absorption wavelength.

  7. Ultrafast X-ray Diffraction Theory Jianshu Cao* and Kent R. Wilson

    E-Print Network [OSTI]

    Cao, Jianshu

    notablely using ultrafast optical pump-probe pulses. Unfortunately, except for a few favorable cases of a sample is initiated by an ultrafast optical laser pulse and then probed by an ultrafast X-ray pulse initiated by the optical pump pulse in real time and real space.9-11 From a simple viewpoint, ultrafast X

  8. Diffraction line-profile shape by synchrotron and laboratory x-ray sources* Davor Balzar `Jo,Peter W. Stephens 2,and Hassel Ledbetter 1

    E-Print Network [OSTI]

    Balzar, Davor

    Diffraction line-profile shape by synchrotron and laboratory x-ray sources* Davor Balzar `Jo-line profiles obtained at the X3Bl NSLS powder-diffraction beamline and with a standard CuKa,,, sealed source) divergence but also on the character of diffraction-line profiles at high angles. A theoretical expression

  9. Composition and strain in thin Si{sub 1-x}Ge{sub x} virtual substrates measured by micro-Raman spectroscopy and x-ray diffraction

    SciTech Connect (OSTI)

    Perova, T. S.; Wasyluk, J.; Waldron, A. [Department of Electronic and Electrical Engineering, Trinity College, University of Dublin, Dublin 2 (Ireland); Lyutovich, K.; Kasper, E.; Oehme, M. [Institut fuer Halbleitertechnik, Universitaet Stuttgart, Pfaffenwaldring 47, 70569 Stuttgart (Germany); Rode, K. [School of Physics, CRANN, Trinity College, University of Dublin, Dublin 2 (Ireland)

    2011-02-01T23:59:59.000Z

    Micro-Raman spectroscopy was employed for the determination of the germanium content, x and strain, {epsilon}, in ultrathin SiGe virtual substrates grown directly on Si by molecular beam epitaxy. The growth of highly relaxed SiGe layers was achieved by the introduction of point defects at a very low temperature during the initial stage of growth. SiGe virtual substrates with thicknesses in the range 40-200 nm with a high Ge content (up to 50%) and degree of relaxation, r, in the range 20%-100% were investigated using micro-Raman spectroscopy and x-ray diffraction (XRD) techniques. The Ge content, x, and strain, {epsilon}, were estimated from equations describing Si-Si, Si-Ge, and Ge-Ge Raman vibrational modes, modified in this study for application to thin SiGe layers. The alteration of the experimentally derived equations from previous studies was performed using independent data for x and r obtained from XRD reciprocal space maps. A number of samples consisting of a strained-silicon (s-Si) layer deposited on a SiGe virtual substrate were also analyzed. The stress value for the s-Si varied from 0.54 to 2.75 GPa, depending on the Ge-content in the virtual substrates. These results are in good agreement with theoretically predicted values.

  10. On the ammonolysis of Ga{sub 2}O{sub 3}: An XRD, neutron diffraction and XAS investigation of the oxygen-rich part of the system Ga{sub 2}O{sub 3}-GaN

    SciTech Connect (OSTI)

    Roehrens, D.; Brendt, J.; Samuelis, D. [Institute of Physical Chemistry, RWTH Aachen University, Landoltweg 2, 52056 Aachen (Germany); Martin, M., E-mail: martin@rwth-aachen.d [Institute of Physical Chemistry, RWTH Aachen University, Landoltweg 2, 52056 Aachen (Germany)

    2010-03-15T23:59:59.000Z

    We investigated the ammonolysis of beta-Ga{sub 2}O{sub 3} at elevated temperatures by means of ex situ X-ray diffraction, ex situ neutron diffraction and in situ X-ray absorption spectroscopy. Within the detection limits of these methods, we can rule out the existence of a crystalline or amorphous oxynitride phase that is not derived from wurtzite-type GaN. No evidence for a beta-Ga{sub 2}O{sub 3} related oxynitride phase was found, and the nitrogen solubility in beta-Ga{sub 2}O{sub 3} was found to be below the detection limit of about 2-3 at% in the anionic sublattice. These findings were obtained by monitoring the anionic occupancy factors and the lattice parameters of the beta-Ga{sub 2}O{sub 3} phase obtained from total diffraction pattern refinement with the Rietveld method and by linear combination fitting of the X-ray absorption spectra that were recorded during the ammonolysis. - Graphical abstract: The ammonolysis of beta-Ga{sub 2}O{sub 3} powders forming GaN at temperatures of 600-780 deg. C was monitored by means of XRD, neutron diffraction and X-ray absorption spectroscopy in order to identify the possible intermediates and the solubility limit of nitrogen in the oxide lattice.

  11. 7 Å Resolution in Protein 2-Dimentional-Crystal X-Ray Diffraction at Linac Coherent Light Source

    SciTech Connect (OSTI)

    Pedrini, Bill; Tsai, Ching-Ju; Capitani, Guido; Padeste, Celestino; Hunter, Mark; Zatsepin, Nadia A.; Barty, Anton; Benner, Henry; Boutet, Sebastien; Feld, Geoffrey K.; Hau-Riege, Stefan; Kirian, Rick; Kupitz, Christopher; Messerschmidt, Marc; Ogren, John I.; Pardini, Tommaso; Segelke, Brent; Williams, Garth J.; Spence , John C.; Abela, Rafael; Coleman, Matthew A.; Evans, James E.; Schertler, Gebhard; Frank, Matthias; Li, Xiao-Dan

    2014-06-09T23:59:59.000Z

    Membrane proteins arranged as two-dimensional (2D) crystals in the lipid en- vironment provide close-to-physiological structural information, which is essential for understanding the molecular mechanisms of protein function. X-ray diffraction from individual 2D crystals did not represent a suitable investigation tool because of radiation damage. The recent availability of ultrashort pulses from X-ray Free Electron Lasers (X-FELs) has now provided a mean to outrun the damage. Here we report on measurements performed at the LCLS X-FEL on bacteriorhodopsin 2D crystals mounted on a solid support and kept at room temperature. By merg- ing data from about a dozen of single crystal diffraction images, we unambiguously identified the diffraction peaks to a resolution of 7 °A, thus improving the observable resolution with respect to that achievable from a single pattern alone. This indicates that a larger dataset will allow for reliable quantification of peak intensities, and in turn a corresponding increase of resolution. The presented results pave the way to further X-FEL studies on 2D crystals, which may include pump-probe experiments at subpicosecond time resolution.

  12. In-situ stoichiometry determination using x-ray fluorescence generated by reflection-high-energy-electron-diffraction

    SciTech Connect (OSTI)

    Keenan, Cameron; Chandril, Sandeep; Lederman, David [Department of Physics and Multifunctional Materials Laboratory, West Virginia University, Morgantown, West Virginia 26506 (United States); Myers, T. H. [Department of Physics and Multifunctional Materials Laboratory, West Virginia University, Morgantown, West Virginia 26506 (United States); Materials Science, Engineering, and Commercialization Program, Texas State University-San Marcos, San Marcos, Texas 78666 (United States)

    2011-06-01T23:59:59.000Z

    A major challenge in the stoichiometric growth of complex oxide compounds is the control of the relative compositions of the constituent materials. A potential avenue for compositional analysis during growth is the use of x-ray fluorescence generated during reflection high energy electron diffraction measurements. Using this technique, relative compositions of Y and Mn in molecular beam epitaxy grown YMnO{sub 3} samples were studied. Comparing the results with Rutherford back scattering spectroscopy suggests that the technique has the potential for real-time analysis of elemental fluxes and stoichiometry control during sample growth.

  13. Variable growth modes of CaF[sub 2] on Si(111) determined by x-ray photoelectron diffraction

    SciTech Connect (OSTI)

    Denlinger, J.D.; Rotenberg, E. (Department of Physics, University of California, Berkeley, California 94720 (United States) Materials Sciences Division, Lawrence Berkeley Laboratory, Berkeley, California 94720 (United States)); Hessinger, U.; Leskovar, M. (Department of Physics FM-15, University of Washington, Seattle, Washington 98195 (United States)); Olmstead, M.A. (Department of Physics FM-15, University of Washington, Seattle, Washington 98195 (United States) Materials Sciences Division, Lawrence Berkeley Laboratory, Berkeley, California 94720 (United States))

    1993-04-26T23:59:59.000Z

    Chemical discrimination of bulk and interface Ca 2[ital p] x-ray photoelectron diffraction modulations is used to identify three growth regimes during the initial stages of CaF[sub 2] epitaxy on Si(111). Low flux, high temperature conditions produce island growth atop a nonwetting, chemically reacted Ca-F interface layer. Changing the growth kinetics by increasing the flux produces more laminar growth. Lowering the substrate temperature produces a more stoichiometric CaF[sub 2] interface layer that results in immediate wetting and laminar growth.

  14. Diffraction imaging for in-situ characterization of double-crystal x-ray monochromators

    E-Print Network [OSTI]

    Stoupin, Stanislav; Heald, Steve M; Brewe, Dale; Meron, Mati

    2015-01-01T23:59:59.000Z

    Imaging of the Bragg reflected x-ray beam is proposed and validated as an in-situ method for characterization of performance of double-crystal monochromators under the heat load of intense synchrotron radiation. A sequence of images is collected at different angular positions on the reflectivity curve of the second crystal and analyzed. The method provides rapid evaluation of the wavefront of the exit beam, which relates to local misorientation of the crystal planes along the beam footprint on the thermally distorted first crystal. The measured misorientation can be directly compared to results of finite element analysis. The imaging method offers an additional insight on the local intrinsic crystal quality over the footprint of the incident x-ray beam.

  15. An assessment of the resolution limitation due to radiation-damage in X-ray diffraction microscopy

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Howells, M.R.; Beetz, T.; Chapman, H.N.; Cui, C.; Holton, J.M.; Jacobsen, C.J.; Kirz, J.; Lima, E.; Marchesini, S.; Miao, H.; et al

    2009-03-01T23:59:59.000Z

    X-ray diffraction microscopy (XDM) is a new form of x-ray imaging that is being practiced at several third-generation synchrotron-radiation x-ray facilities. Nine years have elapsed since the technique was first introduced and it has made rapid progress in demonstrating high-resolution three-dimensional imaging and promises few-nm resolution with much larger samples than can be imaged in the transmission electron microscope. Both life- and materials-science applications of XDM are intended, and it is expected that the principal limitation to resolution will be radiation damage for life science and the coherent power of available x-ray sources for material science. In this paper wemore »address the question of the role of radiation damage. We use a statistical analysis based on the so-called "dose fractionation theorem" of Hegerl and Hoppe to calculate the dose needed to make an image of a single life-science sample by XDM with a given resolution. We find that for simply-shaped objects the needed dose scales with the inverse fourth power of the resolution and present experimental evidence to support this finding. To determine the maximum tolerable dose we have assembled a number of data taken from the literature plus some measurements of our own which cover ranges of resolution that are not well covered otherwise. The conclusion of this study is that, based on the natural contrast between protein and water and "Rose-criterion" image quality, one should be able to image a frozen-hydrated biological sample using XDM at a resolution of about 10 nm.« less

  16. An assessment of the resolution limitation due to radiation-damage in X-ray diffraction microscopy

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Howells, M.R.; Beetz, T.; Chapman, H.N.; Cui, C.; Holton, J.M.; Jacobsen, C.J.; Kirz, J.; Lima, E.; Marchesini, S.; Miao, H.; Sayre, D.; Shapiro, D.A.; Spence, J.C.H.; Starodub, D.

    2009-03-01T23:59:59.000Z

    X-ray diffraction microscopy (XDM) is a new form of x-ray imaging that is being practiced at several third-generation synchrotron-radiation x-ray facilities. Nine years have elapsed since the technique was first introduced and it has made rapid progress in demonstrating high-resolution three-dimensional imaging and promises few-nm resolution with much larger samples than can be imaged in the transmission electron microscope. Both life- and materials-science applications of XDM are intended, and it is expected that the principal limitation to resolution will be radiation damage for life science and the coherent power of available x-ray sources for material science. In this paper we address the question of the role of radiation damage. We use a statistical analysis based on the so-called "dose fractionation theorem" of Hegerl and Hoppe to calculate the dose needed to make an image of a single life-science sample by XDM with a given resolution. We find that for simply-shaped objects the needed dose scales with the inverse fourth power of the resolution and present experimental evidence to support this finding. To determine the maximum tolerable dose we have assembled a number of data taken from the literature plus some measurements of our own which cover ranges of resolution that are not well covered otherwise. The conclusion of this study is that, based on the natural contrast between protein and water and "Rose-criterion" image quality, one should be able to image a frozen-hydrated biological sample using XDM at a resolution of about 10 nm.

  17. Femtosecond diffractive imaging with a soft-X-ray free-electron laser (CXIDB ID 3)

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Chapman, H. N.

    The diffraction pattern of this entry corresponds to the one shown in **figure 2a** of the corresponding citation.

  18. The use of X-ray diffraction, microscopy, and magnetic measurements for analysing microstructural features of a duplex stainless steel

    SciTech Connect (OSTI)

    Ribeiro Miranda, M.A. [Instituto de Fisica, Universidade Federal do Ceara, Campus do Pici, Caixa Postal 6030, CEP 60455-760 Fortaleza/CE (Brazil)]. E-mail: marcus@fisica.ufc.br; Sasaki, J.M. [Instituto de Fisica, Universidade Federal do Ceara, Campus do Pici, Caixa Postal 6030, CEP 60455-760 Fortaleza/CE (Brazil); Tavares, S.S.M. [PGMEC/TEM, Universidade Federal Fluminense, Rua Passo da Patria, 156, CEP 24210-240, Niteroi/RJ (Brazil); de Abreu, H.F.G. [Depto. Engenharia Meca-hat nica, Universidade Federal do Ceara (Brazil); Neto, J.M. [Instituto de Fisica, Universidade Federal do Rio de Janeiro (Brazil)

    2005-05-15T23:59:59.000Z

    X-ray diffraction, light optical microscopy, and magnetization saturation measurements were employed to analyse the microstructural features of a UNS S31803 duplex stainless steel modified by high-temperature treatments. The samples were heated to 1300 deg. C and cooled by different ways to produce five different microstructures. Solution treatments at 1000 deg. C were also employed to produce another five conditions. Three methods were employed to determine the austenite/ferrite proportions. X-ray diffraction gave higher austenite values than the other methods, due to the influence of texture, but can be successfully used to determine the microstrain level in each phase. Magnetic saturation measurement is a very simple and precise method for quantification of austenite and ferrite volume fractions in samples that were fast-cooled and slow-cooled. Light microscopy can give a fast and precise measurement of the phase proportions and reveals important features related to the morphology of the phases, but in the samples where the austenite content is low, quantification becomes difficult and imprecise.

  19. LOW TEMPERATURE X-RAY DIFFRACTION STUDIES OF NATURAL GAS HYDRATE SAMPLES FROM THE GULF OF MEXICO

    SciTech Connect (OSTI)

    Rawn, Claudia J [ORNL; Sassen, Roger [Texas A& M University; Ulrich, Shannon M [ORNL; Phelps, Tommy Joe [ORNL; Chakoumakos, Bryan C [ORNL; Payzant, E Andrew [ORNL

    2008-01-01T23:59:59.000Z

    Clathrate hydrates of methane and other small alkanes occur widespread terrestrially in marine sediments of the continental margins and in permafrost sediments of the arctic. Quantitative study of natural clathrate hydrates is hampered by the difficulty in obtaining pristine samples, particularly from submarine environments. Bringing samples of clathrate hydrate from the seafloor at depths without compromising their integrity is not trivial. Most physical property measurements are based on studies of laboratory-synthesized samples. Here we report X-ray powder diffraction measurements of a natural gas hydrate sample from the Green Canyon, Gulf of Mexico. The first data were collected in 2002 and revealed ice and structure II gas hydrate. In the subsequent time the sample has been stored in liquid nitrogen. More recent X-ray powder diffraction data have been collected as functions of temperature and time. This new data indicates that the larger sample is heterogeneous in ice content and shows that the amount of sII hydrate decreases with increasing temperature and time as expected. However, the dissociation rate is higher at lower temperatures and earlier in the experiment.

  20. A 31?T split-pair pulsed magnet for single crystal x-ray diffraction at low temperature

    SciTech Connect (OSTI)

    Duc, F.; Frings, P.; Nardone, M.; Billette, J.; Zitouni, A.; Delescluse, P.; Béard, J.; Nicolin, J. P.; Rikken, G. L. J. A. [Laboratoire National des Champs Magnétiques Intenses, CNRS-INSA-UJF-UPS, 143, avenue de Rangueil, F-31400 Toulouse (France); Fabrèges, X. [Laboratoire National des Champs Magnétiques Intenses, CNRS-INSA-UJF-UPS, 143, avenue de Rangueil, F-31400 Toulouse (France); Laboratoire Léon Brillouin, UMR12 CEA-CNRS Bât 563 CEA Saclay, 91191 Gif sur Yvette Cedex (France); Roth, T. [European Synchrotron Radiation Facility, Boîte Postale 220, F-38043 Grenoble Cedex (France); European XFEL GmbH, Albert-Einstein-Ring 19, D-22761 Hamburg (Germany); Detlefs, C.; Lesourd, M.; Zhang, L. [European Synchrotron Radiation Facility, Boîte Postale 220, F-38043 Grenoble Cedex (France)

    2014-05-15T23:59:59.000Z

    We have developed a pulsed magnet system with panoramic access for synchrotron x-ray diffraction in magnetic fields up to 31?T and at low temperature down to 1.5?K. The apparatus consists of a split-pair magnet, a liquid nitrogen bath to cool the pulsed coil, and a helium cryostat allowing sample temperatures from 1.5 up to 250?K. Using a 1.15?MJ mobile generator, magnetic field pulses of 60?ms length were generated in the magnet, with a rise time of 16.5?ms and a repetition rate of 2 pulses/h at 31?T. The setup was validated for single crystal diffraction on the ESRF beamline ID06.

  1. Femtosecond diffractive imaging with a soft-X-ray free-electron laser

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville Power AdministrationField8,Dist. CategoryFebruaryFebruary 17,Time-Delay X-ray Holography

  2. Oxygen diffusivity in silicon derived from dynamical X-ray diffraction

    SciTech Connect (OSTI)

    Will, J.; Groeschel, A.; Bergmann, C.; Steinrueck, H.-G.; Magerl, A. [Crystallography and Structural Physics, University of Erlangen-Nuernberg, Staudtstr. 3, 91058 Erlangen (Germany); Kot, D.; Schubert, M. A.; Kissinger, G. [IHP, Im Technologiepark 25, 15236 Frankfurt (Oder) (Germany)

    2013-02-21T23:59:59.000Z

    Thickness dependent Pendelloesung oscillations are highly sensitive to strain fields from defects in a host crystal. Based on this, we present a novel technique to measure the precipitation kinetics of oxygen in silicon already at its early stage of clustering at high temperatures. At 900 Degree-Sign C, precipitates with a radius smaller than 4 nm and with a density of 1 {+-} 0.5 Multiplication-Sign 10{sup 13} 1/cm{sup 3} were observed. The technique was calibrated by complementary scanning transmission electron microscope and energy dispersive X-ray measurements in the range of normal diffusivity yielding a diffusion constant of 1.7 {+-} 0.1 Multiplication-Sign 10{sup -12}cm{sup 2}/s, which is close to the literature value of 2.074 Multiplication-Sign 10{sup -12}cm{sup 2}/s. The measurements have been made with the characteristic K{sub {alpha}1}-line of a high voltage tungsten X-ray tube at 59.31 keV, which provides the opportunity to illuminate through complex sample environments like high temperature scattering furnaces.

  3. X-ray Diffraction and Multi-Frame Phase Contrast Imaging Diagnostics for IMPULSE at the Advanced Photon Source

    SciTech Connect (OSTI)

    Iverson, Adam [National Security Technologies, LLC; Carlson, Carl [National Security Technologies, LLC; Young, Jason [National Security Technologies, LLC; Curtis, Alden [National Security Technologies, LLC; Jensen, Brian [Los Alamos National Laboratory; Ramos, Kyle [Los Alamos National Laboratory; Yeager, John [Los Alamos National Laboratory; Montgomery, David [Los Alamos National Laboratory; Fezza, Kamel [Argonne National Laboratory

    2013-07-08T23:59:59.000Z

    The diagnostic needs of any dynamic loading platform present unique technical challenges that must be addressed in order to accurately measure in situ material properties in an extreme environment. The IMPULSE platform (IMPact system for Ultrafast Synchrotron Experiments) at the Advanced Photon Source (APS) is no exception and, in fact, may be more challenging, as the imaging diagnostics must be synchronized to both the experiment and the 60 ps wide x-ray bunches produced at APS. The technical challenges of time-resolved x-ray diffraction imaging and high-resolution multi-frame phase contrast imaging (PCI) are described in this paper. Example data from recent IMPULSE experiments are shown to illustrate the advances and evolution of these diagnostics with a focus on comparing the performance of two intensified CCD cameras and their suitability for multi-frame PCI. The continued development of these diagnostics is fundamentally important to IMPULSE and many other loading platforms and will benefit future facilities such as the Dynamic Compression Sector at APS and MaRIE at Los Alamos National Laboratory.

  4. Structures and phase diagrams of N2 and CO to 13 GPa by x-ray diffraction

    SciTech Connect (OSTI)

    Mills, R.L.; Olinger, B.; Cromer, D.T.

    1986-03-01T23:59:59.000Z

    The structures and phase transitions of N2 and CO were studied by powder x-ray diffraction from 100 to 300 K and 4 to 13 GPa. Three solid phases, US , delta, and epsilon, were observed in each material. The known US and delta solids were confirmed to have hexagonal space group P63/mmc and cubic space group Pm3n, respectively. From refinements using photographic x-ray intensities, the new epsilon-N2 and epsilon-CO structures were determined to be rhombohedral R3c. There are eight ordered molecules in the epsilon-N2 unit cell with a = 5.928 A and = 85.14 at 110 K and 7.8 GPa, and eight ordered molecules in the epsilon-CO unit cell with a = 6.059 A and = 85.73 at 100 K and 5.5 GPa. The CO molecules are randomly oriented head to tail. The delta--epsilon transition takes place through an ordering and small displacement of the N2 and CO molecules, accompanied by a slight extension of the lattice along a cube diagonal. Molar volumes are presented over an expanded P-T region. Recent theoretical calculations using lattice energies, molecular dynamics, and symmetry correlations correctly predict features in the N2 and CO phase diagrams.

  5. Tuning of colossal dielectric constant in gold-polypyrrole composite nanotubes using in-situ x-ray diffraction techniques

    SciTech Connect (OSTI)

    Sarma, Abhisakh; Sanyal, Milan K., E-mail: milank.sanyal@saha.ac.in [Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata 700 064 (India)

    2014-09-15T23:59:59.000Z

    In-situ x-ray diffraction technique has been used to study the growth process of gold incorporated polypyrrole nanotubes that exhibit colossal dielectric constant due to existence of quasi-one-dimensional charge density wave state. These composite nanotubes were formed within nanopores of a polycarbonate membrane by flowing pyrrole monomer from one side and mixture of ferric chloride and chloroauric acid from other side in a sample cell that allows collection of x-ray data during the reaction. The size of the gold nanoparticle embedded in the walls of the nanotubes was found to be dependent on chloroauric acid concentration for nanowires having diameter more than 100 nm. For lower diameter nanotubes the nanoparticle size become independent of chloroauric acid concentration and depends on the diameter of nanotubes only. The result of this study also shows that for 50 nm gold-polypyrrole composite nanotubes obtained with 5.3 mM chloroauric acid gives colossal dielectric constant of about 10{sup 7}. This value remain almost constant over a frequency range from 1Hz to 10{sup 6} Hz even at 80 K temperature.

  6. Thermoelastic study of nanolayered structures using time-resolved X-ray diffraction at high repetition rate

    SciTech Connect (OSTI)

    Navirian, H. A.; Schick, D., E-mail: daniel.schick@uni-potsdam.de; Leitenberger, W.; Bargheer, M. [Institut für Physik und Astronomie, Universität Potsdam, Karl-Liebknecht-Str. 24-25, 14476 Potsdam (Germany); Gaal, P.; Shayduk, R. [Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Wilhelm-Conrad-Röntgen Campus, BESSY II, Albert-Einstein-Str. 15, 12489 Berlin (Germany)

    2014-01-13T23:59:59.000Z

    We investigate the thermoelastic response of a nanolayered sample composed of a metallic SrRuO{sub 3} electrode sandwiched between a ferroelectric Pb(Zr{sub 0.2}Ti{sub 0.8})O{sub 3} film with negative thermal expansion and a SrTiO{sub 3} substrate. SrRuO{sub 3} is rapidly heated by fs-laser pulses with 208?kHz repetition rate. Diffraction of X-ray pulses derived from a synchrotron measures the transient out-of-plane lattice constant c of all three materials simultaneously from 120?ps to 5??s with a relative accuracy up to ?c/c?=?10{sup ?6}. The in-plane propagation of sound is essential for understanding the delayed out-of-plane compression of Pb(Zr{sub 0.2}Ti{sub 0.8})O{sub 3}.

  7. Time-resolved X-ray diffraction studies of laser-induced acoustic wave propagation in bilayer metallic thin crystals

    SciTech Connect (OSTI)

    Er, Ali Oguz [Department of Physics and Astronomy, Western Kentucky University, Bowling Green, Kentucky 42101 (United States); Tang, Jau, E-mail: jautang@gate.sinica.edu.tw, E-mail: prentzepis@ece.tamu.edu [Research Center for Applied Sciences Academia Sinica, Taipei, Taiwan (China); Chen, Jie [Key Laboratory for Laser Plasmas (Ministry of Education) and Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240 (China); Rentzepis, Peter M., E-mail: jautang@gate.sinica.edu.tw, E-mail: prentzepis@ece.tamu.edu [Department of Electrical and Computer Engineering, Texas A and M University, College Station, Texas 77843 (United States)

    2014-09-07T23:59:59.000Z

    Phonon propagation across the interface of a Cu/Ag(111) bilayer and transient lattice disorder, induced by a femtosecond 267?nm pulse, in Ag(111) crystal have been measured by means of time resolved X-ray diffraction. A “blast” force due to thermal stress induced by suddenly heated electrons is formed within two picoseconds after excitation and its “blast wave” propagation through the interface and Ag (111) crystal was monitored by the shift and broadening of the rocking curve, I vs. ?, as a function of time after excitation. Lattice disorder, contraction and expansion as well as thermal strain formation and wave propagation have also been measured. The experimental data and mechanism proposed are supported by theoretical simulations.

  8. X-ray diffraction, optical microscopy, and microhardness studies of gas nitrided titanium alloys and titanium aluminide

    SciTech Connect (OSTI)

    Sha, W. [Metals Research Group, School of Planning, Architecture and Civil Engineering, The Queen's University of Belfast, Belfast BT7 1NN (United Kingdom)], E-mail: w.sha@qub.ac.uk; Haji Mat Don, M.A.; Mohamed, A.; Wu, X.; Siliang, B. [Metals Research Group, School of Planning, Architecture and Civil Engineering, The Queen's University of Belfast, Belfast BT7 1NN (United Kingdom); Zhecheva, A. [Sifco Applied Surface Concepts (UK) Ltd., Division of Sifco Industries, Inc., European Headquarters, 38 Walkers Road, Moons Moat North, Redditch, Worcestershire B98 9HD (United Kingdom)

    2008-03-15T23:59:59.000Z

    Thermochemical surface gas nitriding of {beta}21s, Timetal 205 and a Ti-Al alloy was conducted using differential scanning calorimeter equipment, in nominally pure nitrogen at 850 deg. C and 950 deg. C ({beta}21s), 730 deg. C and 830 deg. C (Timetal 205), and 950 deg. C and 1050 deg. C (Ti-Al) for 1 h, 3 h and 5 h. X-ray diffraction analyses showed new phases formed in the nitrided layer, depending on the alloy and the time and the temperature of nitriding. Microstructures were analyzed using optical microscopy. Cross-sectional microhardness profiles of cross-sectional samples after nitriding were obtained using a Knoop indenter.

  9. Diffusion-driven precipitate growth and ripening of oxygen precipitates in boron doped silicon by dynamical x-ray diffraction

    SciTech Connect (OSTI)

    Will, J., E-mail: will@krist.uni-erlangen.de; Gröschel, A.; Bergmann, C.; Magerl, A. [Crystallography and Structural Physics, University of Erlangen-Nürnberg, Staudtstr. 3, 91058 Erlangen (Germany); Spiecker, E. [Center for Nanoanalysis and Electron Microscopy, University of Erlangen-Nürnberg, Cauerstr. 6, 91058 Erlangen (Germany)

    2014-03-28T23:59:59.000Z

    X-ray Pendellösung fringes from three silicon single crystals measured at 900?°C are analyzed with respect to density and size of oxygen precipitates within a diffusion-driven growth model and compared with TEM investigations. It appears that boron doped (p+) material shows a higher precipitate density and a higher strain than moderately (p-) boron crystals. In-situ diffraction reveals a diffusion-driven precipitate growth followed by a second growth regime in both materials. An interpretation of the second growth regime in terms of Ostwald ripening yields surface energy values (around 70?erg/cm{sup 2}) similar to published data. Further, an increased nucleation rate by a factor of ?13 is found in the p+ sample as compared to a p- sample at a nucleation temperature of 450?°C.

  10. Observation of localized heating phenomena during microwave heating of mixed powders using in situ x-ray diffraction technique

    SciTech Connect (OSTI)

    Sabelström, N., E-mail: sabelstrom.n.aa@m.titech.ac.jp; Hayashi, M. [Department of Metallurgy and Ceramics Science, Tokyo Institute of Technology, Tokyo 152-8552 (Japan); Watanabe, T. [Department of Chemistry and Materials Science, Tokyo Institute of Technology, Tokyo 152-8552 (Japan); Nagata, K. [Department of Conservation Science, Tokyo University of the Arts, 12-8 Ueno Park, Taito-ku, Tokyo (Japan)

    2014-10-28T23:59:59.000Z

    In materials processing research using microwave heating, there have been several observations of various phenomena occurring known as microwave effects. One significant example of such a phenomenon is increased reaction kinetics. It is believed that there is a possibility that this might be caused by localized heating, were some reactants would attain a higher than apparent temperature. To examine whether such thermal gradients are indeed possible, mixed powders of two microwave non-absorbers, alumina and magnesia, were mixed with graphite, a known absorber, and heated in a microwave furnace. During microwave irradiation, the local temperatures of the respective sample constituents were measured using an in situ x-ray diffraction technique. In the case of the alumina and graphite sample, a temperature difference of around 100?°C could be observed.

  11. Synthesis and single crystal x-ray diffraction study of a Schiff base derived from 4-acylpyrazolone and 2-aminophenol

    SciTech Connect (OSTI)

    Sharma, Naresh; Kant, Rajni, E-mail: vivek-gupta2k2@hotmail.com; Gupta, Vivek K., E-mail: vivek-gupta2k2@hotmail.com [Department of Physics and Electronics, University of Jammu, Jammu Tawi - 180006 (India); Jadeja, R. N. [Department of Chemistry, Faculty of Science, The M. S. University of Baroda, Vadodara-390002 (India)

    2014-04-24T23:59:59.000Z

    The title compound, (Z)-1-(3-chlorophenyl)-4[1((2hydroxyphenyl)amino)propylidene] -3-methyl-1H-pyrazol-5(4H)-one was synthesized by refluxing compound 1-(m-chlorophenyl)-3-methyl-4-propionyl-5-pyrazolone, with 2-aminophenol in ethanol. The compound crystallizes in the orthorhombic crystal system with space group Pca2{sub 1} having unit cell parameters: a = 26.2993(8), b = 7.0724(2) and c = 18.7170(5)Å. The structure contains two crystallographically independent molecules, A, and, B, in the asymmetric unit cell. The crystal structure was solved by direct method using single crystal X-ray diffraction data collected at room temperature and refined by full-matrix least-squares procedures to a final R- value of 0.049 for 5207 observed reflections.

  12. A camera for coherent diffractive imaging and holography with a soft-X-ray free electron laser

    SciTech Connect (OSTI)

    Bajt, S; Chapman, H N; Spiller, E; Alameda, J; Woods, B; Frank, M; Bogan, M J; Barty, A; Boutet, S; Marchesini, S; Hau-Riege, S P; Hajdu, J; Shapiro, D

    2007-09-24T23:59:59.000Z

    We describe a camera to record coherent scattering patterns with a soft-X-ray free-electron laser. The camera consists of a laterally-graded multilayer mirror which reflects the diffraction pattern onto a CCD detector. The mirror acts as a bandpass filter both for wavelength and angle, which isolates the desired scattering pattern from non-sample scattering or incoherent emission from the sample. The mirror also solves the particular problem of the extreme intensity of the FEL pulses, which are focused to greater than 10{sup 14} W/cm{sup 2}. The strong undiffracted pulse passes through a hole in the mirror and propagates on to a beam dump at a distance behind the instrument rather than interacting with a beamstop placed near the CCD. The camera concept is extendable for the full range of the fundamental wavelength of the FLASH FEL (i.e. between 6 nm and 60 nm) and into the water window. We have fabricated and tested various multilayer mirrors for wavelengths of 32 nm, 16 nm, 13.5 nm, and 4.5 nm. At the shorter wavelengths mirror roughness must be minimized to reduce scattering from the mirror. We have recorded over 30,000 diffraction patterns at the FLASH free-electron laser with no observable mirror damage or degradation of performance.

  13. The SF6 monolayer on graphite by X-ray diffraction C. Marti, T. Ceva, B. Croset, C. De Beauvais and A. Thomy (*)

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    1517 The SF6 monolayer on graphite by X-ray diffraction C. Marti, T. Ceva, B. Croset, C. De) Résumé. 2014 La structure du film de SF6 adsorbé sur graphite a été étudiée entre 35 et 180 K par du cristal 3D, ce qui explique le mouillage imparfait du graphite par SF6. Dans le domaine où la

  14. Characterization of Chain Molecular Assemblies in Long-Chain, Layered Silver Thiolates: A Joint Infrared Spectroscopy and X-ray Diffraction Study

    E-Print Network [OSTI]

    Parikh, Atul N.

    , and Theoretical DiVisions, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 ReceiVed: October 1, 1998 of infrared transmission spectroscopy and powder X-ray diffraction. The structural attributes elucidated. The three-dimensional network of 1D channels alternates between the chain layers. All the chain structural

  15. Amyloid Treatment and Research Program key research findings: Definition of the electron microscopic structure and x-ray diffraction pattern of amyloid

    E-Print Network [OSTI]

    Finzi, Adrien

    , which for the first time defined the biochemical nature and source of the amyloid fibril in this form microscopic structure and x-ray diffraction pattern of amyloid fibrils in 1967, providing key insight of amyloidosis. Characterization of the protein deposits in dialysis-associated amyloidosis as 2- microglobulin

  16. Intrafacet migration effects in InGaN/GaN structures grown on triangular GaN ridges studied by submicron beam x-ray diffraction

    E-Print Network [OSTI]

    Sirenko, Andrei

    Intrafacet migration effects in InGaN/GaN structures grown on triangular GaN ridges studied for x-ray diffraction and reciprocal space mapping of InGaN/GaN multiple-quantum-well MQW structures grown on the sidewalls of 10- m-wide triangular GaN ridges with 1-1.1 facets. Samples were produced

  17. Progress in Three-Dimensional Coherent X-Ray Diffraction Imaging

    SciTech Connect (OSTI)

    Marchesini, S; Chapman, H N; Barty, A; Howells, M R; Cui, C; Spence, J H; Weierstall, U; Noy, A; Hau-Riege, S P; Kinney, J M; Shapiro, D; Beetz, T; Jacobsen, C; Lima, E; Minor, A M; He, H

    2005-09-30T23:59:59.000Z

    The Fourier inversion of phased coherent diffraction patterns offers images without the resolution and depth-of-focus limitations of lens-based tomographic systems. We report on our recent experimental images inverted using recent developments in phase retrieval algorithms, and summarize efforts that led to these accomplishments. These include ab-initio reconstruction of a two-dimensional test pattern, infinite depth of focus image of a thick object, and its high-resolution ({approx}10 nm resolution) three-dimensional image. Developments on the structural imaging of low density aerogel samples are discussed.

  18. Synchrotron X-ray diffraction studies of phase transitions and mechanical properties of nanocrystalline materials at high pressure

    SciTech Connect (OSTI)

    Prilliman, Gerald Stephen

    2003-09-01T23:59:59.000Z

    The behavior of nanocrystals under extreme pressure was investigated using synchrotron x-ray diffraction. A major part of this investigation was the testing of a prototype synchrotron endstation on a bend magnet beamline at the Advanced Light Source for high pressure work using a diamond anvil cell. The experiments conducted and documented here helped to determine issues of efficiency and accuracy that had to be resolved before the construction of a dedicated ''super-bend'' beamline and endstation. The major conclusions were the need for a cryo-cooled monochromator and a fully remote-controllable pressurization system which would decrease the time to change pressure and greatly reduce the error created by the re-placement of the diamond anvil cell after each pressure change. Two very different types of nanocrystal systems were studied, colloidal iron oxide (Fe{sub 2}O{sub 3}) and thin film TiN/BN. Iron oxide nanocrystals were found to have a transition from the {gamma} to the {alpha} structure at a pressure strongly dependent on the size of the nanocrystals, ranging from 26 GPa for 7.2 nm nanocrystals to 37 GPa for 3.6 nm nanocrystals. All nanocrystals were found to remain in the {alpha} structure even after release of pressure. The transition pressure was also found, for a constant size (5.7 nm) to be strongly dependent on the degree of aggregation of the nanocrystals, increasing from 30 GPa for completely dissolved nanocrystals to 45 GPa for strongly aggregated nanocrystals. Furthermore, the x-ray diffraction pattern of the pressure induced {alpha} phase demonstrated a decrease in intensity for certain select peaks. Together, these observations were used to make a complete picture of the phase transition in nanocrystalline systems. The size dependence of the transition was interpreted as resulting from the extremely high surface energy of the {alpha} phase which would increase the thermodynamic offset and thereby increase the kinetic barrier to transition that must be overridden with pressure. The anomalous intensities in the x-ray diffraction patterns were interpreted as being the result of stacking faults, indicating that the mechanism of transition proceeds by the sliding of {gamma}(111) planes to form {alpha}(001) planes. The increasing transition pressure for more aggregated samples may be due to a positive activation volume, retarding the transition for nanocrystals with less excess (organic) volume available to them. The lack of a reverse transition upon decompression makes this interpretation more difficult because of the lack of an observable hysteresis, and it is therefore difficult to ascertain kinetic effects for certain. In the case TiN/BN nanocomposite systems, it was found that the bulk modulus (B{sub 0}) of the TiN nanoparticles was not correlated to the observed hardness or Young's modulus of the macroscopic thin film. This indicates that the origin of the observed super-hard nature of these materials is not due to any change in the Ti-N interatomic potential. Rather, the enhanced hardness must be due to nano-structural effects. It was also found that during pressurization the TiN nanoparticles developed a great deal of strain. This strain can be related to defects induced in individual nanoparticles which generates strain in adjacent particles due to the highly coupled nature of the system.

  19. Growth and nucleation regimes in boron doped silicon by dynamical x-ray diffraction

    SciTech Connect (OSTI)

    Will, J., E-mail: johannes.will@fau.de; Gröschel, A.; Bergmann, C.; Weißer, M.; Magerl, A. [Crystallography and Structural Physics, University of Erlangen-Nürnberg, Staudtstr. 3, 91058 Erlangen (Germany)

    2014-09-15T23:59:59.000Z

    The oxygen precipitation of highly (17.5 m? cm) and moderately (4.5 ? cm) boron (B) doped silicon (Si) crystals at 780?°C is investigated by following in-situ the evolution of diffraction Pendellösung oscillations. All samples show an initial diffusion-driven growth process which may change over into Ostwald ripening. For the highly doped sample and involving a nucleation step at 450?°C for 30?h, the precipitate density ? is enhanced by a factor of 8 as compared to the moderately doped sample. The influence of a high B concentration on ? is dramatically higher for the samples directly heated to 780?°C, where an enhancement factor of 80 is found. Considering Ostwald ripening as a second growth regime reveals consistent ripening rates and surface energies ? with those found at 900?°C in a previous publication.

  20. Reconstruction of a yeast cell from X-ray diffraction data

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Thibault, Pierre; Elser, Veit; Jacobsen, Chris; Shapiro, David; Sayre, David

    2006-06-21T23:59:59.000Z

    Details are provided of the algorithm used for the reconstruction of yeast cell images in the recent demonstration of diffraction microscopy by Shapiro, Thibault, Beetz, Elser, Howells, Jacobsen, Kirz, Lima, Miao, Nieman & Sayre [Proc. Natl Acad. Sci. USA (2005), 102, 15343-15346]. Two refinements of the iterative constraint-based scheme are developed to address the current experimental realities of this imaging technique, which include missing central data and noise. A constrained power operator is defined whose eigenmodes allow the identification of a small number of degrees of freedom in the reconstruction that are negligibly constrained as a result of the missing data. To achieve reproducibility in the algorithm's output, a special intervention is required for these modes. Weak incompatibility of the constraints caused by noise in both direct and Fourier space leads to residual phase fluctuations. This problem is addressed by supplementing the algorithm with an averaging method. The effect of averaging may be interpreted in terms of an effective modulation transfer function, as used in optics, to quantify the resolution. The reconstruction details are prefaced with simulations of wave propagation through a model yeast cell. These show that the yeast cell is a strong-phase-contrast object for the conditions in the experiment.

  1. Reconstruction of a yeast cell from X-ray diffraction data

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Thibault, Pierre; Elser, Veit; Jacobsen, Chris; Shapiro, David; Sayre, David

    2006-06-21T23:59:59.000Z

    Details are provided of the algorithm used for the reconstruction of yeast cell images in the recent demonstration of diffraction microscopy by Shapiro, Thibault, Beetz, Elser, Howells, Jacobsen, Kirz, Lima, Miao, Nieman & Sayre [Proc. Natl Acad. Sci. USA (2005), 102, 15343-15346]. Two refinements of the iterative constraint-based scheme are developed to address the current experimental realities of this imaging technique, which include missing central data and noise. A constrained power operator is defined whose eigenmodes allow the identification of a small number of degrees of freedom in the reconstruction that are negligibly constrained as a result of the missingmore »data. To achieve reproducibility in the algorithm's output, a special intervention is required for these modes. Weak incompatibility of the constraints caused by noise in both direct and Fourier space leads to residual phase fluctuations. This problem is addressed by supplementing the algorithm with an averaging method. The effect of averaging may be interpreted in terms of an effective modulation transfer function, as used in optics, to quantify the resolution. The reconstruction details are prefaced with simulations of wave propagation through a model yeast cell. These show that the yeast cell is a strong-phase-contrast object for the conditions in the experiment.« less

  2. A Super-high Angular Resolution Principle for Coded-mask X-ray Imaging Beyond the Diffraction Limit of Single Pinhole

    E-Print Network [OSTI]

    Chen Zhang; Shuang Nan Zhang

    2008-06-25T23:59:59.000Z

    High angular resolution X-ray imaging is always demanded by astrophysics and solar physics, which can be realized by coded-mask imaging with very long mask-detector distance in principle. Previously the diffraction-interference effect has been thought to degrade coded-mask imaging performance dramatically at low energy end with very long mask-detector distance. In this work the diffraction-interference effect is described with numerical calculations, and the diffraction-interference cross correlation reconstruction method (DICC) is developed in order to overcome the imaging performance degradation. Based on the DICC, a super-high angular resolution principle (SHARP) for coded-mask X-ray imaging is proposed. The feasibility of coded mask imaging beyond the diffraction limit of single pinhole is demonstrated with simulations. With the specification that the mask element size of 50* 50 square micrometers and the mask-detector distance of 50 m, the achieved angular resolution is 0.32 arcsec above about 10 keV, and 0.36 arcsec at 1.24 keV where diffraction can not be neglected. The on-axis source location accuracy is better than 0.02 arcsec. Potential applications for solar observations and wide-field X-ray monitors are also shortly discussed.

  3. Structure of a zeolite ZSM-5-Bithiophene complex as determined by high-resolution synchrotron X-ray powder diffraction

    SciTech Connect (OSTI)

    Eylem, C.; Hriljac, J.A. [Brookhaven National Laboratory, Upton, NY (United States)] [Brookhaven National Laboratory, Upton, NY (United States); Ramamurthy, V.; Corbin, D.R. [Du Pont Co., Wilmington, DE (United States)] [Du Pont Co., Wilmington, DE (United States); Parise, J.B. [State Univ. of New York, Stony Brook, NY (United States)] [State Univ. of New York, Stony Brook, NY (United States)

    1996-04-01T23:59:59.000Z

    The structure of a zeolite ZSM-5 complex with ca. 4 molecules/unit cell of bithiophene was determined by high-resolution synchrotron X-ray powder diffraction. In adopts monoclinic symmetry in space group P2{sub 1}/n ({alpha} unique) between room temperature and 25 K, with refined lattice parameters at 25 K of a = 20.0614(4), b = 19.8251(4), c = 13.3623(4) {Angstrom}, and a = 90.848(2){degrees}. Structural modeling and Rietveld refinements showed that there are two crystallographically unique bithiophene molecules, each with an occupancy factor of ca. 0.5. One bithiophene is localized at the center of the straight channels with one of the rings residing at the intersection with the sinusoidal channels. The other molecule lies in the sinusoidal channels and projects partially into the straight channels. The relationship between polythiophene chain length and the formation of conducting polythiophene molecular wires in the ZSM-5 framework is discussed. 32 refs., 4 figs., 3 tabs.

  4. Purification, crystallization and preliminary X-ray diffraction analysis of the human mismatch repair protein MutS[beta

    SciTech Connect (OSTI)

    Tseng, Quincy; Orans, Jillian; Hast, Michael A.; Iyer, Ravi R.; Changela, Anita; Modrich, Paul L.; Beese, Lorena S. (Duke)

    2012-03-16T23:59:59.000Z

    MutS{beta} is a eukaryotic mismatch repair protein that preferentially targets extrahelical unpaired nucleotides and shares partial functional redundancy with MutS{alpha} (MSH2-MSH6). Although mismatch recognition by MutS{alpha} has been shown to involve a conserved Phe-X-Glu motif, little is known about the lesion-binding mechanism of MutS{beta}. Combined MSH3/MSH6 deficiency triggers a strong predisposition to cancer in mice and defects in msh2 and msh6 account for roughly half of hereditary nonpolyposis colorectal cancer mutations. These three MutS homologs are also believed to play a role in trinucleotide repeat instability, which is a hallmark of many neurodegenerative disorders. The baculovirus overexpression and purification of recombinant human MutS{beta} and three truncation mutants are presented here. Binding assays with heteroduplex DNA were carried out for biochemical characterization. Crystallization and preliminary X-ray diffraction analysis of the protein bound to a heteroduplex DNA substrate are also reported.

  5. X-ray diffraction analysis of InGaP/GaAs heterointerfaces grown by metalorganic chemical vapor deposition

    SciTech Connect (OSTI)

    Nittono, T.; Hyuga, F. [NTT System Electronics Laboratories 3-1, Morinosato Wakamiya, Atsugi-shi, Kanagawa, 243-01 (Japan)] [NTT System Electronics Laboratories 3-1, Morinosato Wakamiya, Atsugi-shi, Kanagawa, 243-01 (Japan)

    1997-03-01T23:59:59.000Z

    InGaP/GaAs heterointerfaces grown by metalorganic chemical vapor deposition have been characterized by a high-resolution x-ray diffraction analysis of multiple quantum well structures. The flow of AsH{sub 3} to InGaP surface produces an InGaAs-like interfacial layer at the GaAs-on-InGaP interface, indicating P atoms of the InGaP surface are easily replaced by As atoms. The flow of PH{sub 3} to GaAs surface, on the other hand, does not make any detectable interfacial layer, indicating that almost no As atoms of the GaAs surface are replaced by P atoms. It is also found that the flow of trimethylgallium (TMG) to the InGaP surface produces a GaP-like interfacial layer. This interfacial layer is probably formed by the reaction between TMG and excessive P atoms on the InGaP surface or residual PH{sub 3} in the growth chamber. {copyright} {ital 1997 American Institute of Physics.}

  6. Growth kinetics of CaF[sub 2]/Si(111) heteroepitaxy: An x-ray photoelectron diffraction study

    SciTech Connect (OSTI)

    Denlinger, J.D.; Rotenberg, E. (Department of Physics and Lawrence Berkeley Laboratory, University of California, Berkeley, California 94720 (United States)); Hessinger, U.; Leskovar, M.; Olmstead, M.A. (Department of Physics, FM-15, University of Washington, Seattle, Washington 98195 (United States))

    1995-02-15T23:59:59.000Z

    Kinetic variations of the initial stages of CaF[sub 2] growth on Si(111) by molecular-beam epitaxy are studied with the [ital in] [ital situ] combination of x-ray photoelectron spectroscopy and diffraction. After the formation of a chemically reacted interface layer, the morphology of the subsequent bulk layers is found to be dependent on the substrate temperature and incident flux rate, as well as the initial interface structure. For substrate temperatures above [similar to]600 [degree]C, subsequent layers do not easily wet the interface layer, and a transition is observed from a three-dimensional island formation at low flux to a laminar growth following the coalescence of bilayer islands at higher flux. At lower substrate temperatures ([similar to]450 [degree]C), a different stoichiometry and structure of the interface layer leads to laminar growth at all fluxes, but with a different bulk nucleation behavior. Crystalline heteroepitaxy is not observed when growth initiates at room temperature, but homoepitaxy does proceed at room temperature if the first few layers are deposited at a high temperature. The different growth regimes are discussed in terms of a kinetic model separating step and terrace nucleation where, contrary to homoepitaxy, step nucleation leads to islanded growth.

  7. Study of calcium-containing orthophosphates of NaZr{sub 2}(PO{sub 4}){sub 3} structural type by high-temperature X-ray diffraction

    SciTech Connect (OSTI)

    Orlova, A. I.; Kanunov, A. E., E-mail: a.kanunov@mail.ru [Nizhni Novgorod State University (Russian Federation); Samoilov, S. G.; Kazakova, A. Yu.; Kazantsev, G. N. [Leipunsky Institute of Physics and Power Engineering (Russian Federation)] [Leipunsky Institute of Physics and Power Engineering (Russian Federation)

    2013-03-15T23:59:59.000Z

    Orthophosphates Ca{sub 0.5}Ti{sub 2}(PO{sub 4}){sub 3}, Ca{sub 0.5}Zr{sub 2}(PO{sub 4}){sub 3}, Ca{sub 0.75}Zr{sub 2}(SiO{sub 4}){sub 0.5}(PO{sub 4}){sub 2.5}, and CaMg{sub 0.5}Zr{sub 1.5}(PO{sub 4}){sub 3} (structural type NaZr{sub 2}(PO{sub 4}){sub 3}), having different occupancies of interframework positions by calcium, have been prepared by the sol-gel method with the subsequent thermal treatment of dried gels and investigated by IR spectroscopy and X-ray diffraction. The analytical indexing of X-ray diffraction patterns is performed within the sp. gr. R3{sup -}. High-temperature X-ray diffraction was used to investigate the behavior of the orthophosphates upon heating: thermal expansion in the temperature range of 20-610 Degree-Sign C (up to 500 Degree-Sign C for Ca{sub 0.5}Zr{sub 2}(PO{sub 4}){sub 3}). The coefficients of thermal expansion are calculated from the shift of diffraction peaks. The unit-cell parameters of crystals at different temperatures are determined. The dependences of thermal expansion and its anisotropy on the occupancy of cation M positions by calcium are revealed.

  8. Hydrostatic Compression Curve for Triamino-Trinitrobenzene Determined to 13.0 GPa with Powder X-Ray Diffraction

    SciTech Connect (OSTI)

    Stevens, Lewis L.; Velisavljevic, Nenad; Hooks, Daniel E.; Dattelbaum, Dana M. (LANL)

    2008-08-22T23:59:59.000Z

    Using powder X-ray diffraction in conjunction with a diamond anvil cell (DAC), the unit cell volume of triamino-trinitrobenzene (TATB) has been measured from ambient pressure to 13 GPa. The resultant isotherm is compared with previous theoretical (Byrd and Rice and Pastine and Bernecker) and experimental (Olinger and Cady) works. While all reports are consistent to approximately 2 GPa, our measurements reveal a slightly stiffer TATB material than reported by Olinger and Cady and an intermediate compressibility compared with the isotherms predicted by the two theoretical works. Analysis of the room temperature isotherm using the semi-empirical, Murnaghan, Birch-Murnaghan, and Vinet equations of state (EOS) provided a determination of the isothermal bulk modulus (K{sub 0}) and its pressure-derivative (K{sub 0}') for TATB. From these fits to our P-V isotherm, from ambient pressure to 8 GPa, the average results for the zero-pressure bulk modulus and its pressure derivative were found to be 14.7 GPa and 10.1, respectively. For comparison to shock experiments on pressed TATB powder and its plastic-bonded formulation PBX 9502 (95% TATB, 5% Kel-F 800), the isotherm was transformed to the pseudo-velocity U{sub s}-u{sub p} plane using the Rankine-Hugoniot jump conditions. This analysis provides an extrapolated bulk sound speed, c{sub 0}=1.70 km s{sup -1}, for TATB and its agreement with a previous determination (c{sub 0}=1.43 km s{sup -1}) is discussed. Furthermore, our P-V and corresponding U{sub s}-u{sub p} curves reveal a subtle cusp at approximately 8 GPa. This cusp is discussed in relation to similar observations made for the aromatic hydrocarbons anthracene, benzene and toluene, graphite, and trinitrotoluene (TNT).

  9. High-pressure single-crystal X-ray diffraction of Tl{sub 2}SeO{sub 4}

    SciTech Connect (OSTI)

    Grzechnik, Andrzej [Departamento de Fisica de la Materia Condensada, Universidad del Pais Vasco, E-48080 Bilbao (Spain)], E-mail: andrzej.grzechnik@ehu.es; Breczewski, Tomasz; Friese, Karen [Departamento de Fisica de la Materia Condensada, Universidad del Pais Vasco, E-48080 Bilbao (Spain)

    2008-11-15T23:59:59.000Z

    The effect of pressure on the crystal structure of thallium selenate (Tl{sub 2}SeO{sub 4}) (Pmcn, Z=4), containing the Tl{sup +} cations with electron lone pairs, has been studied with single-crystal X-ray diffraction in a diamond anvil cell up to 3.64 GPa at room temperature. No phase transition has been observed. The compressibility data are fitted by a Murnaghan equation of state with the zero-pressure bulk modulus B{sub 0}=29(1) GPa and the unit-cell volume at ambient pressure V{sub 0}=529.6(8) A{sup 3} (B'=4.00). Tl{sub 2}SeO{sub 4} is the least compressible in the c direction, while the pressure-induced changes of the a and b lattice parameters are quite similar. These observations can be explained by different pressure effects on the nine- and 11-fold coordination polyhedra around the two non-equivalent Tl atoms. The SeO{sub 4}{sup 2-} tetrahedra are not rigid units and become more distorted. Their contribution to the compressibility is small. The effect of pressure on the isotypical oxide materials A{sub 2}TO{sub 4} with the {beta}-K{sub 2}SO{sub 4} structure is discussed. It appears that the presence of electron lone pairs on the Tl{sup +} cation does not seem to influence the compressibility of Tl{sub 2}SeO{sub 4}. - Graphical abstract: Pressure dependence of normalized lattice parameters and unit-cell volumes in Tl{sub 2}SeO{sub 4} (Pmcn, Z=4). The solid line is the Murnaghan equation of state.

  10. Phases of underpotentially deposited Hg on Au(111): An in situ surface X-ray diffraction study

    SciTech Connect (OSTI)

    Li, J.; Abruna, H.D. [Cornell Univ., Ithaca, NY (United States)] [Cornell Univ., Ithaca, NY (United States)

    1997-04-10T23:59:59.000Z

    We report on an in situ surface X-ray diffraction study of the underpotential deposition (UPD) of mercury on Au(111). We have observed three UPD phases present at potentials prior to bulk mercury deposition. These phases consist of two well-ordered intermediate states and what appears to be either a fully discharged two-dimensional liquid Hg layer or a monolayer of an amorphous Hg-Au alloy. Both ordered intermediate phases have hexagonal structures with lattice vectors that are rotated 30{degree} from those of the Au(111) substrate. The first phase (phase I), present at a potential of +0.68 V, was only observed on fresh flame-annealed Au(111) electrodes and appears to be an open incommensurate structure with a lattice constant of 3.86 {+-} 0.03 A. This phase appears to be metastable since it changes to a second ordered phase (phase II) after a certain time. The second phase has a more compact lattice with a = 3.34 {+-} 0.01 A and appears to be a commensurate 2x2 structure with 2/3 of the Hg atoms at threefold hollow sites and 1/3 on atop sites. Similar to the first one, this phase is also metastable and can be transformed to a final, fully discharged, state of a two-dimensional liquid Hg layer or an amorphous Hg-Au alloy. The entire Hg UPD process, from Hg{sup 2+} to the fully discharged metallic Hg layer, agrees well with a multistep mechanism based on previous electrochemical kinetic studies on polycrystalline Au electrodes. 31 refs., 10 figs., 2 tabs.

  11. The growth of epitaxial iron oxides on platinum (111) as studied by X-ray photoelectron diffraction, scanning tunneling microscopy, and low energy electron diffraction

    SciTech Connect (OSTI)

    Kim, Y.J.

    1995-05-01T23:59:59.000Z

    Three complementary surface structure probes, x-ray photoelectron diffraction (XPD), scanning tunneling microscopy (STM), and low-energy electron diffraction (LEED) have been combined in a single instrument. This experimental system has been utilized to study the structure and growth mechanisms of iron oxide films on Pt(111); these films were formed by first depositing a single overlayer of Fe with a certain coverage in monolayers (ML`s), and then thermally oxidizing it in an oxygen atmosphere. For films up to {approximately}1 ML in thickness, a bilayer of Fe and O similar to those in FeO(111) is found to form. In agreement with prior studies, STM and LEED show this to be an incommensurate oxide film forming a lateral superlattice with short- and long-range periodicities of {approximately}3.1 {Angstrom} and {approximately}26.0 {Angstrom}. XPD in addition shows a topmost oxygen layer to be relaxed inward by -0.6 {Angstrom} compared to bulk FeO(111), and these are new structural conclusions. The oxygen stacking in the FeO(111) bilayer is dominated by one of two possible binding sites. For thicker iron oxide films from 1.25 ML to 3.0 ML, the growth mode is essentially Stranski-Krastanov: iron oxide islands form on top of the FeO(111) bilayer mentioned above. For iron oxide films of 3.0 ML thickness, x-ray photoelectron spectroscopy (XPS) yields an Fe 2p{sub 3/2} binding energy and an Fe:O stoichiometry consistent with the presence of Fe{sub 3}O{sub 4}. Our XPD data further prove this overlayer to be Fe{sub 3}O{sub 4}(111)-magnetite in two almost equally populated domains with a 180{degrees} rotation between them. The structural parameters for this Fe{sub 3}O{sub 4} overlayer generally agree with those of a previous LEED study, except that we find a significant difference in the first Fe-O interplanar spacing. This work demonstrates the considerable benefits to be derived by using this set of complementary surface structure probes in such epitaxial growth studies.

  12. An in-vacuum x-ray diffraction microscope for use in the 0.7-2.9 keV range

    SciTech Connect (OSTI)

    Vine, D. J. [Australian Research Council Centre of Excellence for Coherent X-ray Science (Australia); School of Physics, University of Melbourne, Victoria 3010 (Australia); Argonne National Laboratory, Argonne, Illinois 60439 (United States); Williams, G. J. [Australian Research Council Centre of Excellence for Coherent X-ray Science (Australia); SLAC National Accelerator Laboratory, Menlo Park, California 94025 (United States); Clark, J. N. [Australian Research Council Centre of Excellence for Coherent X-ray Science (Australia); Department of Physics, La Trobe University, Bundoora, Victoria 3086 (Australia); London Centre for Nanotechnology, University College, London WC1E 6BT (United Kingdom); Putkunz, C. T.; Abbey, B.; Nugent, K. A. [Australian Research Council Centre of Excellence for Coherent X-ray Science (Australia); School of Physics, University of Melbourne, Victoria 3010 (Australia); Pfeifer, M. A. [Australian Research Council Centre of Excellence for Coherent X-ray Science (Australia); Cornell High Energy Synchrotron Source, Cornell University, Ithaca, New York 14850 (United States); Legnini, D.; Roehrig, C.; Wrobel, E.; McNulty, I. [Argonne National Laboratory, Argonne, Illinois 60439 (United States); Huwald, E. [Department of Physics, La Trobe University, Bundoora, Victoria 3086 (Australia); Riessen, G. van; Peele, A. G. [Australian Research Council Centre of Excellence for Coherent X-ray Science (Australia); Department of Physics, La Trobe University, Bundoora, Victoria 3086 (Australia); Beetz, T.; Irwin, J.; Feser, M.; Hornberger, B. [Xradia, Inc., 4385 Hopyard Road, Pleasanton, California 94588 (United States)

    2012-03-15T23:59:59.000Z

    A dedicated in-vacuum coherent x-ray diffraction microscope was installed at the 2-ID-B beamline of the Advanced Photon Source for use with 0.7-2.9 keV x-rays. The instrument can accommodate three common implementations of diffractive imaging; plane wave illumination; defocused-probe (Fresnel diffractive imaging) and scanning (ptychography) using either a pinhole, focused or defocused probe. The microscope design includes active feedback to limit motion of the optics with respect to the sample. Upper bounds on the relative optics-to-sample displacement have been measured to be 5.8 nm(v) and 4.4 nm(h) rms/h using capacitance micrometry and 27 nm/h using x-ray point projection imaging. The stability of the measurement platform and in-vacuum operation allows for long exposure times, high signal-to-noise and large dynamic range two-dimensional intensity measurements to be acquired. Finally, we illustrate the microscope's stability with a recent experimental result.

  13. X-Ray Studies of GaN Film Grown on Si Using Electrochemical Deposition Techniques

    SciTech Connect (OSTI)

    Al-Heuseen, K.; Hashim, M. R. [Nano-Optoelectronics Research and Technology Laboratory School of Physics, Universiti Sains Malaysia (USM), 11800 Minden, Penang (Malaysia)

    2011-03-30T23:59:59.000Z

    This paper reports on the X-ray studies of GaN thin films deposited on Si (111) substrate at different current density using electrochemical deposition technique. The structural properties of GaN films were studied by X-ray diffraction (XRD). XRD analysis showed that hexagonal wurtzite and cubic zinc blende GaN phases were both deposited on Si (111). The lattice constants, the average size of h-GaN crystals and the in-plane (along a-axis) and out of plane (along c-axis) strains were calculated from XRD analysis.

  14. X-ray diffraction and extended X-ray absorption fine structure study of epitaxial mixed ternary bixbyite Pr{sub x}Y{sub 2-x}O{sub 3} (x = 0-2) films on Si (111)

    SciTech Connect (OSTI)

    Niu, G.; Zoellner, M. H.; Zaumseil, P. [IHP, Im Technologiepark 25, 15236 Frankfurt (Oder) (Germany); Pouliopoulos, A. [Department of Physics and Astronomy, University of Bologna, viale C. BertiPichat 6/2, 40127 Bologna (Italy); D'Acapito, F. [Consiglio Nazionale delle Ricerche, Istituto Officina dei Materiali, Operative Group in Grenoble, c/o European Synchrotron Radiation Facility, B.P. 220, 38043 Grenoble (France); Schroeder, T. [IHP, Im Technologiepark 25, 15236 Frankfurt (Oder) (Germany); BTU Cottbus, Konrad-Zuse-Str. 1, 03046 Cottbus (Germany); Boscherini, F. [Department of Physics and Astronomy, University of Bologna, viale C. BertiPichat 6/2, 40127 Bologna (Italy); Consiglio Nazionale delle Ricerche, Istituto Officina dei Materiali, Operative Group in Grenoble, c/o European Synchrotron Radiation Facility, B.P. 220, 38043 Grenoble (France)

    2013-01-28T23:59:59.000Z

    Ternary single crystalline bixbyite Pr{sub x}Y{sub 2-x}O{sub 3} films over the full stoichiometry range (x = 0-2) have been epitaxially grown on Si (111) with tailored electronic and crystallographic structure. In this work, we present a detailed study of their local atomic environment by extended X-ray absorption fine structure at both Y K and Pr L{sub III} edges, in combination with complementary high resolution x-ray diffraction measurements. The local structure exhibits systematic variations as a function of the film composition. The cation coordination in the second and third coordination shells changes with composition and is equal to the average concentration, implying that the Pr{sub x}Y{sub 2-x}O{sub 3} films are indeed fully mixed and have a local bixbyite structure with random atomic-scale ordering. A clear deviation from the virtual crystal approximation for the cation-oxygen bond lengths is detected. This demonstrates that the observed Vegard's law for the lattice variation as a function of composition is based microscopically on a more complex scheme related to local structural distortions which accommodate the different cation-oxygen bond lengths.

  15. High-resolution x-ray diffraction investigation of relaxation and dislocations in SiGe layers grown on (001), (011), and (111) Si substrates

    SciTech Connect (OSTI)

    Zhylik, A.; Benediktovich, A. [Department of Theoretical Physics, Belarusian State University, 4 Fr. Nezavisimosti Avenue, 220030 Minsk, Republic of Belarus (Belarus); Ulyanenkov, A.; Guerault, H. [Bruker AXS GmbH, Oestliche Rheinbrueckenstrasse 49, 76187 Karlsruhe (Germany); Myronov, M.; Dobbie, A.; Leadley, D. R. [Department of Physics, The University of Warwick, Coventry CV4 7AL (United Kingdom); Ulyanenkova, T. [Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany)

    2011-06-15T23:59:59.000Z

    This work presents a detailed characterization, using high-resolution x-ray diffraction, of multilayered Si{sub 1-x}Ge{sub x} heterostructures grown on (001), (011), and (111) Si substrates by reduced pressure chemical vapor deposition. Reciprocal space mapping has been used to determine both the strain and Ge concentration depth profiles within each layer of the heterostructures after initially determining the crystallographic tilt of all the layers. Both symmetric and asymmetric reciprocal space maps were measured on each sample, and the evaluation was performed simultaneously for the whole data set. The ratio of misfit to threading dislocation densities has been estimated for each individual layer based on an analysis of diffuse x-ray scattering from the defects.

  16. Mirrors for X-ray telescopes: Fresnel diffraction-based computation of Point Spread Functions from metrology

    E-Print Network [OSTI]

    Raimondi, Lorenzo

    2014-01-01T23:59:59.000Z

    The imaging sharpness of an X-ray telescope is chiefly determined by the optical quality of its focusing optics, which in turn mostly depends on the shape accuracy and the surface finishing of the grazing incidence X-ray mirrors that compose the optical modules. In order to ensure the imaging performance during the mirror manufacturing, a fundamental step is represented by the prediction of the mirror Point Spread Function (PSF) from the metrology of its surface. Traditionally, the PSF computation in X-rays is assumed to be different depending on whether the surface defects are classified as figure errors or roughness [...] The aim of this work is to overcome this limit, providing analytical formulae, valid at any light wavelength, to compute the PSF of an X-ray mirror shell from the measured longitudinal profiles and the roughness Power Spectral Density (PSD), without distinguishing spectral ranges with different treatments. The method we adopted is based on the Huygens-Fresnel principle to compute the diffr...

  17. Thermal stability in the blended lithium manganese oxide – Lithium nickel cobalt manganese oxide cathode materials: An in situ time-resolved X-Ray diffraction and mass spectroscopy study

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Hu, Enyuan; Bak, Seong Min; Senanayake, Sanjaya D.; Yang, Xiao-Qing; Nam, Kyung-Wan; Zhang, Lulu; Shao, Minhua

    2015-03-01T23:59:59.000Z

    Thermal stabilities of a series of blended LiMn2O4(LMO)-LiNi1/3Co1/3Mn1/3O2 (NCM) cathode materials with different weight ratios were studied by in situ time-resolved X-ray diffraction (XRD) combined with mass spectroscopy in the temperature range of 25°C-580°C under helium atmosphere. Upon heating, the electrochemically delithiated LMO changed into Mn3O4 phase at around 250°C. Formation of MnO with rocksalt structure started at 520°C. This observation is in contrast to the previous report for chemically delithiate LMO in air, in which a process of ?-MnO2 transforming to ?-MnO2 was observed. Oxygen peak was not observed in all cases, presumably as a result of either consumptionmore »by the carbon or detection limit. CO2 profile correlates well with the phase transition and indirectly suggests the oxygen release of the cathode. Introducing NCM into LMO has two effects: first, it makes the high temperature rock-salt phase formation more complicated with more peaks in CO2 profile due to different MO (M = Ni, Mn, Co) phases; secondly, the onset temperature of CO2 release is lowered, implying lowered oxygen release temperature. Upon heating, XRD patterns indicate the NCM part reacts first, followed by the LMO part. This confirms the better thermal stability of LMO over NCM.« less

  18. Thermal stability in the blended lithium manganese oxide – Lithium nickel cobalt manganese oxide cathode materials: An in situ time-resolved X-Ray diffraction and mass spectroscopy study

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Hu, Enyuan [Brookhaven National Lab. (BNL), Upton, NY (United States); Bak, Seong Min [Brookhaven National Lab. (BNL), Upton, NY (United States); Senanayake, Sanjaya D. [Brookhaven National Lab. (BNL), Upton, NY (United States); Yang, Xiao-Qing [Dongguk Univ., Seoul (Korea, Republic of). Dept. of Energy and Materials Engineering; Nam, Kyung-Wan [Dongguk Univ., Seoul (Korea, Republic of). Dept. of Energy and Materials Engineering] (ORCID:0000000162786369); Zhang, Lulu [Hong Kong Univ. of Science and Technology, Clear Water Bay (Hong Kong); Shao, Minhua

    2015-03-01T23:59:59.000Z

    Thermal stabilities of a series of blended LiMn2O4(LMO)-LiNi1/3Co1/3Mn1/3O2 (NCM) cathode materials with different weight ratios were studied by in situ time-resolved X-ray diffraction (XRD) combined with mass spectroscopy in the temperature range of 25°C-580°C under helium atmosphere. Upon heating, the electrochemically delithiated LMO changed into Mn3O4 phase at around 250°C. Formation of MnO with rocksalt structure started at 520°C. This observation is in contrast to the previous report for chemically delithiate LMO in air, in which a process of ?-MnO2 transforming to ?-MnO2 was observed. Oxygen peak was not observed in all cases, presumably as a result of either consumption by the carbon or detection limit. CO2 profile correlates well with the phase transition and indirectly suggests the oxygen release of the cathode. Introducing NCM into LMO has two effects: first, it makes the high temperature rock-salt phase formation more complicated with more peaks in CO2 profile due to different MO (M = Ni, Mn, Co) phases; secondly, the onset temperature of CO2 release is lowered, implying lowered oxygen release temperature. Upon heating, XRD patterns indicate the NCM part reacts first, followed by the LMO part. This confirms the better thermal stability of LMO over NCM.

  19. Study of strain propagation in laser irradiated silicon crystal by time-resolved diffraction of K-{alpha} x-ray probe of different photon energies

    SciTech Connect (OSTI)

    Arora, V.; Bagchi, S.; Chakera, J. A.; Naik, P. A.; Gupta, P. D. [Laser Plasma Division, Raja Ramanna Centre for Advanced Technology, Indore 452 013 (India); Gupta, M.; Gupta, A.; Chaddah, P. [UGC-DAE Consortium for Scientific Research, University Campus, Indore 452 001 (India)

    2013-07-14T23:59:59.000Z

    An experimental study on the time resolved x-ray diffraction from laser shocked silicon crystal, carried out using a 10 TW Ti:sapphire laser system, is presented. The characteristic K{sub {alpha}} x-ray line radiation generated by 45 fs laser produced plasmas of two different target materials (iron and copper) is used as the probe, whereas the stretched pulse of sub-nanosecond duration (pump), derived from the same laser, is used to compress the sample. The use of x-ray probe of different photon energies yields information about the strain over a greater crystal depth. The dynamics of the strain propagation is inferred by monitoring the evolution of rocking curve width of the shocked sample at different time delays between the pump and the probe pulse. The shock velocity deduced from these measurements is {approx}10{sup 6} cm/s, consistent with the sound velocity in bulk silicon. The maximum elastic compression observed is 0.4%, indicating a pressure of 0.8 GPa.

  20. High-Pressure Synchtron Radiation X-Ray Diffraction Studies of Pentaerythritol Tetranitrate C(CH[subscript 2]ONO[subscript 2 ])[subscript 4

    SciTech Connect (OSTI)

    Lipinska-Kalita, K.E.; Pravica, M.; Nicol, M. (UNLV)

    2006-02-02T23:59:59.000Z

    A high-pressure x-ray diffraction study of nanocrystalline pentaerythritol tetranitrate, C(CH{sub 2}ONO{sub 2}){sub 4}, (PETN), has been performed in a diamond-anvil cell at ambient temperature using synchrotron radiation. Pressure-induced alterations in the profiles of the diffraction lines, including their positions, widths and intensities were followed up to 30 GPa in a compressino cycle. The spectral changes in the diffraction patterns at low pressures indicated continuous densification of the tetragonal structure (space group P{bar 4}2{sub 1}c). The diffraction patterns confirmed that PETN compressed from ambient pressure to 7.4 GPa by 17%. At 8.2 GPa and above, several new diffraction lines appeared in the patterns. These lines suggest that the lattice undergoes an incomplete stress-induced structural transformation from the tetragonal to an orthorhombic structure (most probably space group P2{sub 1}22{sub 1}). The mixture of both structures appeared to persist to 30 GPa. The progressive broadening of the diffraction lines as the pressure increased beyond 10 GPa is attributed to the combined diffraction lines of a mixture of two coexisting PETN phases and inhomogeneous pressure distribution within the sample.

  1. X-ray diffraction study of the binding of the antisickling agent 12C79 to human hemoglobin

    SciTech Connect (OSTI)

    Wireko, R.C.; Abraham, D.J. (Virginia Commonwealth Univ., Richmond (United States))

    1991-03-15T23:59:59.000Z

    The hemoglobin binding site of the antisickling agent 12C79 has been determined by x-ray crystallography. 12C79 is recognized as one of the first molecules to reach clinical trials that was designed, de novo, from x-ray-determined atomic coordinates of a protein. Several previous attempts to verify the proposed Hb binding sites via crystallographic studies have failed. Using revised experimental procedures, the authors obtained 12C79-deoxhemoglobin crystals grown after reaction with oxyhemoglobin and cyanoborohydride reduction to stabilize the Schiff base linkage. The difference electron-density Fourier maps show that two 12C79 molecules bind covalently to both symmetry-related N-terminal amino groups of the hemoglobin {alpha} chains. This is in contrast to the original design that proposed the binding of one drug molecule that spans the molecular dyad to interact with both N-terminal {alpha}-amino groups.

  2. Single-particle structure determination by correlations of snapshot X-ray diffraction patterns (CXIDB ID 20)

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Starodub, D.

    This deposition includes the diffraction images generated by the paired polystyrene spheres in random orientations. These images were used to determine and phase the single particle diffraction volume from their autocorrelation functions.

  3. Relationship between dislocations and residual stresses in cold-drawn pearlitic steel analyzed by energy-dispersive X-ray diffraction

    SciTech Connect (OSTI)

    Sato, Shigeo, E-mail: s.sato@imr.tohoku.ac.jp [Institute for Materials Research, Tohoku University, Sendai 980-8577 (Japan); Wagatsuma, Kazuaki [Institute for Materials Research, Tohoku University, Sendai 980-8577 (Japan); Suzuki, Shigeru [Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Sendai 980-8577 (Japan); Kumagai, Masayoshi; Imafuku, Muneyuki [Faculty of Engineering, Tokyo City University, Tokyo 158-8557 (Japan); Tashiro, Hitoshi [Gyoda 361-0011 (Japan); Kajiwara, Kentaro [Japan Synchrotron Radiation Research Institute, Sayo 679-5198 (Japan); Shobu, Takahiasa [Japan Atomic Energy Agency, Sayo 679-5184 (Japan)

    2013-09-15T23:59:59.000Z

    We analyzed the dislocation distribution of cold-drawn pearlitic-steel wire by using the line-profile analysis based on the energy dispersive X-ray diffraction (EDXD). Although this line-profile analysis requires a high resolution in reciprocal space, the resolution for EDXD is generally poor due to the energy resolution of the detector. Our analysis demonstrated that the resolution in the reciprocal space can be maximized at small scattering angles. Using the line-profile analysis based on the EDXD, the microstructural parameters such as the crystallite size and the dislocation density of the ferrite phase in the pearlitic steel were successfully analyzed. In addition, the distribution of the residual stress of the ferrite phase of a pearlitic steel wire was also analyzed using the EDXD measurement. - Highlights: • Energy dispersive X-ray diffraction is applied to the line-profile analysis. • Distribution of dislocations in ferrite in the pearlitic steel wire is analyzed. • Relationship between dislocations and residual stress is discussed.

  4. In situ apparatus for the study of clathrate hydrates relevant to solar system bodies using synchrotron X-ray diffraction and Raman spectroscopy

    E-Print Network [OSTI]

    Day, Sarah J; Evans, Aneurin; Parker, Julia E

    2015-01-01T23:59:59.000Z

    Clathrate hydrates are believed to play a significant role in various solar system environments, e.g. comets, and the surfaces and interiors of icy satellites, however the structural factors governing their formation and dissociation are poorly understood. We demonstrate the use of a high pressure gas cell, combined with variable temperature cooling and time-resolved data collection, to the in situ study of clathrate hydrates under conditions relevant to solar system environments. Clathrates formed and processed within the cell are monitored in situ using synchrotron X-ray powder diffraction and Raman spectroscopy. X-ray diffraction allows the formation of clathrate hydrates to be observed as CO2 gas is applied to ice formed within the cell. Complete conversion is obtained by annealing at temperatures just below the ice melting point. A subsequent rise in the quantity of clathrate is observed as the cell is thermally cycled. Four regions between 100-5000cm-1 are present in the Raman spectra that carry feature...

  5. Coadsorption of sulfate/bisulfate anions with Hg cations during Hg underpotential deposition on Au(111): An in situ x-ray diffraction study

    SciTech Connect (OSTI)

    Li, J.; Abruna, H.D. [Cornell Univ., Ithaca, NY (United States)] [Cornell Univ., Ithaca, NY (United States)

    1997-01-09T23:59:59.000Z

    The first stage of mercury underpotential deposition on Au(111) electrodes in 0.10 M H{sub 2}SO{sub 4} containing 1.0 mM Hg{sup 2+} has been studied by synchrotron X-ray scattering techniques including grazing incidence X-ray diffraction and specular crystal truncation rod measurements. An ordered coadsorbed structure of sulfate/bisulfate anions and Hg cations was found at potentials between the first and second Hg UPD peaks (+0.80 V > E > +0.88 V vs Ag/AgCl(3 M KCl)). The coadsorption structure was found to consist of a compressed Hg honeycomb lattice with the honeycomb centers occupied by sulfate or bisulfate anions. The compression of the lattice is likely due to the formation of mercurous (Hg{sub 2}{sup 2+}) ions which have a much shorter Hg-Hg distance than that in frozen bulk Hg crystals. The net charge transferred under the first Hg UPD peak suggests that the chemical state of the species in the coadsorbed structure is likely Hg{sub 2}SO{sub 4}. Our results indicate that both the chemical state of the mercury cations and the nature of the anions are important in the resulting electrodeposited structures. 38 refs., 8 figs., 1 tab.

  6. Vacancy-induced nanoscale phase separation in KxFe2–ySe? single crystals evidenced by Raman scattering and powder x-ray diffraction

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Lazarevi?, N.; Abeykoon, M.; Stephens, P. W.; Lei, Hechang; Bozin, E. S.; Petrovic, C.; Popovi?, Z. V.

    2012-08-01T23:59:59.000Z

    Polarized Raman scattering spectra of KxFe2–ySe? were analyzed in terms of peculiarities of both I4/m and I4/mmm space group symmetries. The presence of the Raman active modes from both space group symmetries (16 Raman-active modes of the I4/m phase and two Raman-active modes of the I4/mmm phase) confirmed the existence of two crystallographic domains with different space group symmetry in a KxFe2–ySe? sample. High-resolution synchrotron powder x-ray diffraction structural refinement of the same sample confirmed the two-phase description, and determined the atomic positions and occupancies for both domains.

  7. Identification of an incommensurate FeAl{sub 2} overlayer on FeAl(110) using x-ray diffraction and reflectivity

    SciTech Connect (OSTI)

    Baddorf, A.P. [Oak Ridge National Lab., TN (United States); Chandavarkar, S.S. [Tennessee Univ., Knoxville, TN (United States). Dept. of Physics and Astronomy

    1995-06-30T23:59:59.000Z

    FeAl, like NiAl, crystallizes in the CsCl structure. Consequently the (110) planes contain equal amounts of Fe and Al distributed as interlocking rectangles. Unlike the NiAI(110) surface, which retains the (1{times}l) in-plane symmetry of the bulk, FeAl(l10) reconstructs to form an ordered, incommensurate overlayer. The reconstructed layer introduces x-ray diffraction rods at half-order positions along the [1{bar 1}0] direction, and displaced {plus_minus}0.2905 from integer positions along the [001] direction. Peak widths reveal excellent long range order. Specular reflectivity measurements above and below the Fe K{alpha} edge can be reproduced using a model containing a single reconstructed overlayer with an Fe:Al ratio of 1:2, consistent with FeA{sub I}2.

  8. New Insights into the Relationship Between Network Structure and Strain Induced Crystallization in Unvolcanized Natural Rubber by Synchrotron X-ray Diffraction

    SciTech Connect (OSTI)

    Toki, S.; Hsiao, B; Amnuaypornsri, S; Sakdapipanich, J

    2009-01-01T23:59:59.000Z

    The relationship between the network structure and strain-induced crystallization in un-vulcanized as well as vulcanized natural rubbers (NR) and synthetic poly-isoprene rubbers (IR) was investigated via synchrotron wide-angle X-ray diffraction (WAXD) technique. It was found that the presence of a naturally occurring network structure formed by natural components in un-vulcanized NR significantly facilitates strain-induced crystallization and enhances modulus and tensile strength. The stress-strain relation in vulcanized NR is due to the combined effect of chemical and naturally occurring networks. The weakness of naturally occurring network against stress and temperature suggests that vulcanized NR has additional relaxation mechanism due to naturally occurring network. The superior mechanical properties in NR compared with IR are mainly due to the existence of naturally occurring network structure.

  9. X-ray ?-Laue diffraction analysis of Cu through-silicon vias: A two-dimensional and three-dimensional study

    SciTech Connect (OSTI)

    Sanchez, Dario Ferreira; Weleguela, Monica Larissa Djomeni; Audoit, Guillaume; Grenier, Adeline; Gergaud, Patrice; Bleuet, Pierre [Univ. Grenoble Alpes, F-38000 Grenoble (France); CEA/LETI, MINATEC Campus, F-38054 Grenoble (France); Laloum, David [Univ. Grenoble Alpes, F-38000 Grenoble (France); CEA/LETI, MINATEC Campus, F-38054 Grenoble (France); ST Microelectronics, 850 Rue Jean Monnet, F-38920 Crolles (France); Ulrich, Olivier; Micha, Jean-Sébastien; Robach, Odile [Univ. Grenoble Alpes, F-38000 Grenoble (France); CEA/INAC and CNRS, SPrAM, 17 rue des Martyrs, F-38054 Grenoble (France); Lorut, Frédéric [ST Microelectronics, 850 Rue Jean Monnet, F-38920 Crolles (France)

    2014-10-28T23:59:59.000Z

    Here, white X-ray ?-beam Laue diffraction is developed and applied to investigate elastic strain distributions in three-dimensional (3D) materials, more specifically, for the study of strain in Cu 10??m diameter–80??m deep through-silicon vias (TSVs). Two different approaches have been applied: (i) two-dimensional ?-Laue scanning and (ii) ?-beam Laue tomography. 2D ?-Laue scans provided the maps of the deviatoric strain tensor integrated along the via length over an array of TSVs in a 100??m thick sample prepared by Focused Ion Beam. The ?-beam Laue tomography analysis enabled to obtain the 3D grain and elemental distribution of both Cu and Si. The position, size (about 3??m), shape, and orientation of Cu grains were obtained. Radial profiles of the equivalent deviatoric strain around the TSVs have been derived through both approaches. The results from both methods are compared and discussed.

  10. Polarity of semipolar wurtzite crystals: X-ray photoelectron diffraction from GaN(101?1) and GaN(202?1) surfaces

    SciTech Connect (OSTI)

    Romanyuk, O., E-mail: romanyuk@fzu.cz; Ji?í?ek, P.; Bartoš, I. [Institute of Physics, Academy of Sciences of the Czech Republic, Cukrovarnická 10, 162 53 Prague (Czech Republic); Paskova, T. [Department of Electrical and Computer Engineering, North Carolina State University, Raleigh, North Carolina 27606 (United States)

    2014-09-14T23:59:59.000Z

    Polarity of semipolar GaN(101?1) (101?1?) and GaN(202?1) (202?1?) surfaces was determined with X-ray photoelectron diffraction (XPD) using a standard MgK? source. The photoelectron emission from N 1s core level measured in the a-plane of the crystals shows significant differences for the two crystal orientations within the polar angle range of 80–100° from the (0001) normal. It was demonstrated that XPD polar plots recorded in the a-plane are similar for each polarity of the GaN(101?1) and GaN(202?1) crystals if referred to (0001) crystal axes. For polarity determinations of all important GaN(h0h?l) semipolar surfaces, the above given polar angle range is suitable.

  11. X-ray diffraction study on pressure-induced phase transformations and the equation of state of ZnGa{sub 2}Te{sub 4}

    SciTech Connect (OSTI)

    Errandonea, D., E-mail: daniel.errandonea@uv.es [Departamento de Física Aplicada-ICMUV, MALTA Consolider Team, Universidad de Valencia, Edificio de Investigación, C/Dr. Moliner 50, Burjassot, 46100 Valencia (Spain); Kumar, R. S. [High Pressure Science and Engineering Center, Department of Physics and Astronomy, University of Nevada Las Vegas, 4505 Maryland Parkway, Las Vegas, Nevada 89154-4002 (United States); Gomis, O. [Centro de Tecnologías Físicas: Acústica, Materiales y Astrofísica, MALTA Consolider Team, Universitat Politècnica de València, 46022 València (Spain); Manjón, F. J. [Instituto de Diseño para la Fabricación y Producción Automatizada, MALTA Consolider Team, Universitat Politècnica de València, 46022 València (Spain); Ursaki, V. V.; Tiginyanu, I. M. [Institute of Applied Physics, Academy of Sciences of Moldova, 2028 Chisinau (Moldova, Republic of)

    2013-12-21T23:59:59.000Z

    We report on high-pressure x-ray diffraction measurements up to 19.8?GPa in zinc digallium telluride (ZnGa{sub 2}Te{sub 4}) at room temperature. An irreversible structural phase transition takes place at pressures above 12.1?GPa and upon decompression a third polymorph of ZnGa{sub 2}Te{sub 4} was recovered as a metastable phase at pressures below 2.9?GPa. Rietveld refinements were carried out for the three detected polymorphs, being their possible crystal structures reported. The axial compressibilities for the low-pressure phase of ZnGa{sub 2}Te{sub 4} have been determined as well as the equation of state of the low- and high-pressure phases. The reported results are compared with those available in the literature for related compounds. Pressure-induced coordination changes and transition mechanisms are also discussed.

  12. High-pressure X-ray diffraction study of SrMoO{sub 4} and pressure-induced structural changes

    SciTech Connect (OSTI)

    Errandonea, Daniel [MALTA Consolider Team-Departamento de Fisica Aplicada-ICMUV, Universitat de Valencia, Edificio de Investigacion, c/Dr. Moliner 50, 46100 Burjassot, Valencia (Spain)], E-mail: daniel.errandonea@uv.es; Kumar, Ravhi S. [Department of Physics and Astronomy, High Pressure Science and Engineering Center, University of Nevada, 4505 Maryland Parkway, Las Vegas, NV 89154-4002 (United States); Ma Xinghua; Tu Chaoyang [Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002 (China); Graduated School of Chinese Academy of Science, 100039 Beijing (China)

    2008-02-15T23:59:59.000Z

    SrMoO{sub 4} was studied under compression up to 25 GPa by angle-dispersive X-ray diffraction. A phase transition was observed from the scheelite-structured ambient phase (space group I4{sub 1}/a) to a monoclinic fergusonite phase (space group I2/a) at 12.2(9) GPa. The unit-cell parameters of the high-pressure phase are a=5.265(9) A, b=11.191(9) A, c=5.195 (5) A, and {beta}=90.9(1){sup o}, Z=4 at 13.1 GPa. There is no significant volume collapse at the phase transition. No additional phase transitions were observed and on release of pressure the initial phase is recovered, implying that the observed structural modifications are reversible. The reported transition appeared to be a ferroelastic second-order transformation producing a structure that is a monoclinic distortion of the low-pressure phase and was previously observed in compounds isostructural to SrMoO{sub 4}. A possible mechanism for the transition is proposed and its character is discussed in terms of the present data and the Landau theory. Finally, the room temperature equation of states is reported and the anisotropic compressibility of the studied crystal is discussed in terms of the compression of the Sr-O and Mo-O bonds. - Graphical abstract: The evolution of the structure of SrMoO{sub 4} upon compression was established using synchrotron X-ray diffraction and a diamond-anvil cell. A pressure-induced phase transition was found involving a symmetry decrease from tetragonal to monoclinic. A transition mechanism is proposed and its ferroelastic character is discussed in terms of the Landau theory.

  13. X-ray imaging and diffraction from surface phonons on GaAs W. Sauer,a)

    E-Print Network [OSTI]

    Ludwig-Maximilians-Universität, München

    , the driver frequency of the synchrotron was multiplied 102 times by a phase-locked loop PLL , ampli- fied are excited on the GaAs 001 surface by using interdigital transducers, designed for frequencies of up to 900 to measured diffraction profiles at different excitation voltages, the SAW amplitudes were calculated

  14. In situ X-ray diffraction strain-controlled study of Ti–Nb–Zr and Ti–Nb–Ta shape memory alloys: crystal lattice and transformation features

    SciTech Connect (OSTI)

    Dubinskiy, S. [École de technologie supérieure, 1100, Notre-Dame Street West, Montreal, Quebec H3C 1K3 (Canada); National University of Science and Technology “MISIS”, 4, Leninskiy prosp., Moscow 119049 (Russian Federation); Prokoshkin, S. [National University of Science and Technology “MISIS”, 4, Leninskiy prosp., Moscow 119049 (Russian Federation); Brailovski, V., E-mail: vladimir.brailovski@etsmtl.ca [École de technologie supérieure, 1100, Notre-Dame Street West, Montreal, Quebec H3C 1K3 (Canada); Inaekyan, K. [École de technologie supérieure, 1100, Notre-Dame Street West, Montreal, Quebec H3C 1K3 (Canada); Korotitskiy, A. [National University of Science and Technology “MISIS”, 4, Leninskiy prosp., Moscow 119049 (Russian Federation)

    2014-02-15T23:59:59.000Z

    Phase and structure transformations in biomedical Ti–21.8Nb–6.0Zr (TNZ) and Ti–19.7Nb–5.8Ta (TNT) shape memory alloys (at.%) under and without load in the ? 150 to 100 °S temperature range are studied in situ using an original tensile module for a low-temperature chamber of an X-ray diffractometer. Alpha?- and beta-phase lattice parameters, the crystallographic resource of recovery strain, phase and structure transformation sequences, and microstress appearance and disappearance are examined, compared and discussed. For both alloys, the crystallographic resource of recovery strain decreases with temperature increase to become 4.5% for TNZ and 2.5% for TNT alloy (at RT). Loading at low temperatures leads to additional ??-phase formation and reorientation. Heating under load, as compared to strain-free heating, affects the reverse transformation sequence of both alloys in different ways. For TNZ alloy, strain-free heating results in simultaneous ??? and ???? transformations, whereas during heating under stress, they are sequential: ? + ???? precedes ????. For TNT alloy, strain-free heating results in reverse ???? transformation, whereas during heating under stress, ???? transformation is preceded by ??-phase reorientation. - Highlights: • Comparative in situ XRD analysis of Ti–Nb–Zr(Ta) shape memory alloys is realized. • Lattice parameters of ?- and ??-phases are calculated in the ? 150 to + 100 °C range. • The higher the temperature, the lower the ???? transformation strain. • Loading at low temperatures results in ??-phase formation and reorientation. • Transformation sequences upon heating with and without loading are different.

  15. Structural phase transition and magnetism in hexagonal SrMnO{sub 3} by magnetization measurements and by electron, x-ray, and neutron diffraction studies

    SciTech Connect (OSTI)

    Daoud-Aladine, A.; Chapon, L. C.; Knight, K. S. [ISIS facility, Rutherford Appleton Laboratory-CCLRC, Chilton, Didcot, Oxfordshire, OX11 0QX (United Kingdom); Martin, C. [Laboratoire CRISMAT-UMR, 6508 ENSI CAEN, 6, Marechal Juin, 14050 Caen (France); ISIS facility, Rutherford Appleton Laboratory-CCLRC, Chilton, Didcot, Oxfordshire, OX11 0QX (United Kingdom); Hervieu, M. [Laboratoire CRISMAT-UMR, 6508 ENSI CAEN, 6, Marechal Juin, 14050 Caen (France); Brunelli, M. [European Synchrotron Radiation Facility, BP220, F-38043 Grenoble Cedex (France); Radaelli, P. G. [ISIS facility, Rutherford Appleton Laboratory-CCLRC, Chilton, Didcot, Oxfordshire, OX11 0QX (United Kingdom); Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT (United Kingdom)

    2007-03-01T23:59:59.000Z

    The structural and magnetic properties of the hexagonal four-layer form of SrMnO{sub 3} have been investigated by combining magnetization measurements, electron diffraction, and high-resolution synchrotron x-ray and neutron powder diffraction. Below 350 K, there is subtle structural phase transition from hexagonal symmetry (space group P6{sub 3}/mmc) to orthorhombic symmetry (space group C222{sub 1}) where the hexagonal metric is preserved. The second-order phase transition involves a slight tilting of the corner-sharing Mn{sub 2}O{sub 9} units composed of two face-sharing MnO{sub 6} octahedra and the associated displacement of Sr{sup 2+} cations. The phase transition is described in terms of symmetry-adapted displacement modes of the high symmetry phase. Upon further cooling, long range magnetic order with propagation vector k=(0,0,0) sets in below 300 K. The antiferromagnetic structure, analyzed using representation theory, shows a considerably reduced magnetic moment indicating the crucial role played by direct exchange between Mn centers of the Mn{sub 2}O{sub 9} units.

  16. X-ray absorption and diffraction studies of the mixed-phase state of (Cr x V 1 ? x ) 2 O 3

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Pease, D. M.; Frenkel, A. I.; Krayzman, V.; Huang, T.; Shanthakumar, P.; Budnick, J. I.; Metcalf, P.; Chudnovsky, F. A.; Stern, E. A.

    2011-02-01T23:59:59.000Z

    X-ray diffraction and vanadium x-ray absorption near-edge structure (XANES) data have been obtained for (V1-x)?O? samples containing several concentrations of Cr, crossing the metal-insulator transition boundary. For single-phase single-crystal samples our theoretical results are generally in good qualitative agreement with our experimental single-crystal XANES, for both crystal orientations relative to the incident-beam electric vector. However, an anomalous peak occurs for both orientations in the K pre-edge of the single-crystal sample containing 1.2% Cr, a paramagnetic insulator sample that is in the concentration regime corresponding to the room-temperature two-phase (coexistence) region of the phase diagram. Upon increasing the temperature of the 0.4% Cr powdered material to 400 K so that one enters the two-phase region of the phase diagram, a similar peak appears and then diminishes at 600 K. These results, as well as experiments done by others involving room-temperature and low-temperature XANES of a 1.1% Cr sample, suggest that this feature in the V pre-edge structure is associated with the appearance under some circumstances of a small amount of highly distorted VO? octahedra in the interface region between coexisting metal and insulating phases. Finally, we find that, for the two-phase regime, the concentration ratio of the metal-to-insulating phase varies between different regions from a sample batch of uniform composition made by the skull melting method.

  17. Mossbauer spectroscopic and x-ray diffraction studies of structural and magnetic properties of heat-treated ,,Ni0.5Zn0.5...Fe2O4 nanoparticles

    E-Print Network [OSTI]

    Yang, De-Ping

    Mo¨ssbauer spectroscopic and x-ray diffraction studies of structural and magnetic properties-temperature and low-temperature 57 Fe Mo¨ssbauer effect experiments allowed us to determine whether the heat-temperature Mo¨ssbauer spectra revealed that the precursor is paramagnetic, while the heat-treated samples have

  18. Portable total reflection x-ray fluorescence analysis in the identification of unknown laboratory hazards

    SciTech Connect (OSTI)

    Liu, Ying, E-mail: liu.ying.48r@st.kyoto-u.ac.jp; Imashuku, Susumu; Sasaki, Nobuharu; Ze, Long; Kawai, Jun [Department of Materials Science and Engineering, Kyoto University, Yoshida-Honmachi, Sakyo-ku, Kyoto 606-8501 (Japan); Takano, Shotaro; Sohrin, Yoshiki [Institute for Chemical Research, Kyoto University, Gokasho, Uji, Kyoto 611-0011 (Japan); Seki, Hiroko; Miyauchi, Hiroya [Kyoto Prefectural Technology Center for Small and Medium Enterprises, Chudojiminami machi, Shimogyo-ku, Kyoto 600-8813 (Japan)

    2014-05-15T23:59:59.000Z

    In this study, a portable total reflection x-ray fluorescence (TXRF) spectrometer was used to analyze unknown laboratory hazards that precipitated on exterior surfaces of cooling pipes and fume hood pipes in chemical laboratories. With the aim to examine the accuracy of TXRF analysis for the determination of elemental composition, analytical results were compared with those of wavelength-dispersive x-ray fluorescence spectrometry, scanning electron microscope and energy-dispersive x-ray spectrometry, energy-dispersive x-ray fluorescence spectrometry, inductively coupled plasma atomic emission spectrometry, x-ray diffraction spectrometry (XRD), and x-ray photoelectron spectroscopy (XPS). Detailed comparison of data confirmed that the TXRF method itself was not sufficient to determine all the elements (Z?>?11) contained in the samples. In addition, results suggest that XRD should be combined with XPS in order to accurately determine compound composition. This study demonstrates that at least two analytical methods should be used in order to analyze the composition of unknown real samples.

  19. Direct Observations of Sigma Phase Formation in Duplex Stainless Steels using In Situ Synchrotron X-Ray Diffraction

    SciTech Connect (OSTI)

    Elmer, J W; Palmer, T A; Specht, E D

    2006-07-03T23:59:59.000Z

    The formation and growth of sigma phase in 2205 duplex stainless steel was observed and measured in real time using synchrotron radiation during 10 hr isothermal heat treatments at temperatures between 700 C and 850 C. Sigma formed in near-equilibrium quantities during the isothermal holds, starting from a microstructure which contained a balanced mixture of metastable ferrite and austenite. In situ synchrotron diffraction continuously monitored the transformation, and these results were compared to those predicted by thermodynamic calculations. Differences between the calculated and measured amounts of sigma, ferrite and austenite suggest that the thermodynamic calculations underpredict the sigma dissolution temperature by approximately 50 C. The data were further analyzed using a modified Johnson-Mehl-Avrami (JMA) approach to determine kinetic parameters for sigma formation over this temperature range. The initial JMA exponent, n, at low fractions of sigma was found to be approximately 7.0, however, towards the end of the transformation, n decreased to values of approximately 0.75. The change in the JMA exponent was attributed to a change in the transformation mechanism from discontinuous precipitation with increasing nucleation rate, to growth of the existing sigma phase after nucleation site saturation occurred. Because of this change in mechanism, it was not possible to determine reliable values for the activation energy and pre-exponential terms for the JMA equation. While cooling back to room temperature, the partial transformation of austenite resulted in a substantial increase in the ferrite content, but sigma retained its high temperature value to room temperature.

  20. Direct Observations of Sigma Phase Formation in Duplex Stainless Steels Using In Situ Synchrotron X-Ray Diffraction

    SciTech Connect (OSTI)

    Elmer, J. W. [Lawrence Livermore National Laboratory (LLNL); Palmer, T. A. [Lawrence Livermore National Laboratory (LLNL); Specht, Eliot D [ORNL

    2007-01-01T23:59:59.000Z

    The formation and growth of sigma ( ) phase in 2205 duplex stainless steel (DSS) was observed and measured in real time using synchrotron radiation during 10 hour isothermal heat treatments at temperatures between 700 C and 850 C. Sigma formed in near-equilibrium quantities during the isothermal holds, starting from a microstructure which contained a balanced mixture of metastable ferrite and austenite. In-situ synchrotron diffraction continuously monitored the transformation, and these results were compared to those predicted by thermodynamic calculations. The data were further analyzed using a modified Johnson-Mehl-Avrami-Kolmogrov (JMAK) approach to determine kinetic parameters for sigma formation over this temperature range. The initial JMAK exponent, n, at low fractions of sigma was found to be approximately 7.0; however, toward the end of the transformation, n decreased to values of approximately 0.75. The change in the JMAK exponent was attributed to a change in the transformation mechanism from discontinuous precipitation with increasing nucleation rate, to growth of the existing sigma phase after nucleation site saturation occurred. Because of this change in mechanism, it was not possible to determine reliable values for the activation energy and pre-exponential terms for the JMAK equation. While cooling back to room temperature, the partial transformation of austenite resulted in a substantial increase in the ferrite content, but sigma retained its high-temperature value to room temperature.

  1. Thermal equation of state of solid naphthalene to 13 GPa and 773 K: In situ X-ray diffraction study and first principles calculations

    SciTech Connect (OSTI)

    Likhacheva, Anna Y., E-mail: alih@igm.nsc.ru [Sobolev Institute of Geology and Mineralogy, SB RAS, Novosibirsk 630090 (Russian Federation); Rashchenko, Sergey V.; Chanyshev, Artem D.; Litasov, Konstantin D. [Sobolev Institute of Geology and Mineralogy, SB RAS, Novosibirsk 630090 (Russian Federation) [Sobolev Institute of Geology and Mineralogy, SB RAS, Novosibirsk 630090 (Russian Federation); Department of Geology and Geophysics, Novosibirsk State University, Novosibirsk 630090 (Russian Federation); Inerbaev, Talgat M. [Department of Physics and Technical Science, Gumilyov Eurasian National University, Astana (Kazakhstan)] [Department of Physics and Technical Science, Gumilyov Eurasian National University, Astana (Kazakhstan); Kilin, Dmitry S. [Department of Chemistry, University of South Dakota, Vermillion, South Dakota 57069 (United States)] [Department of Chemistry, University of South Dakota, Vermillion, South Dakota 57069 (United States)

    2014-04-28T23:59:59.000Z

    In a wide range of P-T conditions, such fundamental characteristics as compressibility and thermoelastic properties remain unknown for most classes of organic compounds. Here we attempt to clarify this issue by the example of naphthalene as a model representative of polycyclic aromatic hydrocarbons (PAHs). The elastic behavior of solid naphthalene was studied by in situ synchrotron powder X-ray diffraction up to 13 GPa and 773 K and first principles computations to 20 GPa and 773 K. Fitting of the P-V experimental data to Vinet equation of state yielded T 0 = 8.4(3) GPa and T' = 7.2 (3) at V0 = 361 Å(3), whereas the thermal expansion coefficient was found to be extremely low at P > 3 GPa (about 10(-5) K(-1)), in agreement with theoretical estimation. Such a diminishing of thermal effects with the pressure increase clearly demonstrates a specific feature of the high-pressure behavior of molecular crystals like PAHs, associated with a low energy of intermolecular interactions.

  2. IN-SITU XRD OF OPERATING LSFC CATHODES: DEVELOPMENT OF A NEW ANALYTICAL CAPABILITY

    SciTech Connect (OSTI)

    Hardy, John S.; Templeton, Jared W.; Stevenson, Jeffry W.

    2012-11-19T23:59:59.000Z

    A solid oxide fuel cell (SOFC) research capability has been developed that facilitates measuring the electrochemical performance of an operating SOFC while simultaneously performing x-ray diffraction on its cathode. The evolution of this research tool’s development is discussed together with a description of the instrumentation used for in-situ x-ray diffraction (XRD) measurements of operating SOFC cathodes. The challenges that were overcome in the process of developing this capability, which included seals and cathode current collectors, are described together with the solutions that are presently being applied to mitigate them.

  3. X-ray and neutron powder diffraction studies of Ba(Nd{sub x}Y{sub 2-x})CuO{sub 5}

    SciTech Connect (OSTI)

    Liu, G. [Ceramics Division, National Institute of Standards and Technology (NIST), Gaithersburg, MD 20899 (United States); Huang, Q. [NIST Center for Neutron Research, Naperville, IL 60563 (United States); Kaduk, J.A. [INEOS Technologies, Naperville, IL 60563 (United States); Yang, Z. [Yunnan Normal University, Kunming 650092 (China); Lucas, C. [Chemistry and Biochemistry Department, University of Maryland, College Park, MD 20742 (United States); Wong-Ng, W. [Ceramics Division, National Institute of Standards and Technology (NIST), Gaithersburg, MD 20899 (United States)], E-mail: Winnie.wong-ng@nist.gov

    2008-12-15T23:59:59.000Z

    Ba(R,R'){sub 2}CuO{sub 5} (R,R'=lanthanides and Y) plays an important role as a flux-pinning agent in enhancing the superconducting properties of the Ba{sub 2}(R,R')Cu{sub 3}O{sub 6+x} (R,R'=lanthanides and Y) coated conductors. Using X-ray diffraction and neutron diffraction, we found that the Ba(Nd{sub x}Y{sub 2-x})CuO{sub 5} solid solution adopts two structure types. In the Nd-rich region (1.8{<=}x{<=}2.0), the materials are of brown color (commonly referred to as the 'brown phase'), and the structure is tetragonal with space group I4/mbm (no. 127). In the Y-rich region (0.0{<=}x{<=}1.4), the materials are green (commonly referred to as the 'green phase') and the structure is orthorhombic with space group Pnma (no. 62). A two-phase region (1.4

  4. Observations of Ferrite/Austenite Transformations in the Heat Affected Zone of 2205 Duplex Stainless Steel Spot Welds Using Time Resolved X-Ray Diffraction

    SciTech Connect (OSTI)

    Palmer, T; Elmer, J; Babu, S

    2003-10-29T23:59:59.000Z

    Time Resolved X-Ray Diffraction (TRXRD) measurements are made in the Heat Affected Zone (HAZ) of 2205 Duplex Stainless Steel (DSS) spot welds. Both the {gamma} {yields} {delta} and {delta} {yields} {gamma} transformations are monitored as a function of time during the rapid spot weld heating and cooling cycles. These observations are then correlated with calculated thermal cycles. Where the peak temperatures are highest ({approx}1342 C), the {gamma} {yields} {delta} transformation proceeds to completion, leaving a ferritic microstructure at the end of heating. With lower peak temperatures, the {gamma} {yields} {delta} transformation proceeds to only partial completion, resulting in a microstructure containing both transformed and untransformed austenite. Further analyses of the individual diffraction patterns show shifts in the peak positions and peak widths as a function of both time and temperature. In addition, these changes in the peak characteristics are correlated with measured changes in the ferrite volume fraction. Such changes in the peak positions and widths during the {gamma} {yields} {delta} transformation provide an indication of changes occurring in each phase. These changes in peak properties can be correlated with the diffusion of nitrogen and other substitutional alloying elements, which are recognized as the primary mechanisms for this transformation. Upon cooling, the {delta} {yields} {gamma} transformation is observed to proceed from both the completely and partially transformed microstructural regions in the TRXRD data. An examination of the resulting microstructures confirms the TRXRD observation as the evidence shows that austenite both nucleates and grows from the ferritic microstructure at locations closest to the fusion zone boundary and grows from untransformed austenite grains at locations further from this boundary.

  5. Maximum Entropy Method and Charge Flipping, a Powerful Combination to Visualize the True Nature of Structural Disorder from in situ X-ray Powder Diffraction Data

    SciTech Connect (OSTI)

    Samy, A.; Dinnebier, R; van Smaalen, S; Jansen, M

    2010-01-01T23:59:59.000Z

    In a systematic approach, the ability of the Maximum Entropy Method (MEM) to reconstruct the most probable electron density of highly disordered crystal structures from X-ray powder diffraction data was evaluated. As a case study, the ambient temperature crystal structures of disordered {alpha}-Rb{sub 2}[C{sub 2}O{sub 4}] and {alpha}-Rb{sub 2}[CO{sub 3}] and ordered {delta}-K{sub 2}[C{sub 2}O{sub 4}] were investigated in detail with the aim of revealing the 'true' nature of the apparent disorder. Different combinations of F (based on phased structure factors) and G constraints (based on structure-factor amplitudes) from different sources were applied in MEM calculations. In particular, a new combination of the MEM with the recently developed charge-flipping algorithm with histogram matching for powder diffraction data (pCF) was successfully introduced to avoid the inevitable bias of the phases of the structure-factor amplitudes by the Rietveld model. Completely ab initio electron-density distributions have been obtained with the MEM applied to a combination of structure-factor amplitudes from Le Bail fits with phases derived from pCF. All features of the crystal structures, in particular the disorder of the oxalate and carbonate anions, and the displacements of the cations, are clearly obtained. This approach bears the potential of a fast method of electron-density determination, even for highly disordered materials. All the MEM maps obtained in this work were compared with the MEM map derived from the best Rietveld refined model. In general, the phased observed structure factors obtained from Rietveld refinement (applying F and G constraints) were found to give the closest description of the experimental data and thus lead to the most accurate image of the actual disorder.

  6. Lensless Imaging of Whole Biological Cells with Soft X-Rays

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Cells with Soft X-Rays Lensless Imaging of Whole Biological Cells with Soft X-Rays Print Wednesday, 26 May 2010 00:00 A team of scientists has used x-ray diffraction...

  7. Structural characterization of the CeO{sub 2}/Gd{sub 2}O{sub 3} mixed system by synchrotron X-ray diffraction

    SciTech Connect (OSTI)

    Artini, Cristina, E-mail: c.artini@ge.ieni.cnr.it [Dipartimento di Chimica e Chimica Industriale, Universita degli Studi di Genova, Via Dodecaneso 31, 16146 Genova (Italy); Costa, Giorgio A., E-mail: costa@chimica.unige.it [Dipartimento di Chimica e Chimica Industriale, Universita degli Studi di Genova, Via Dodecaneso 31, 16146 Genova (Italy); CNR-SPIN Genova, Corso Perrone 24, 16152 Genova (Italy); Pani, Marcella, E-mail: marcella@chimica.unige.it [Dipartimento di Chimica e Chimica Industriale, Universita degli Studi di Genova, Via Dodecaneso 31, 16146 Genova (Italy); Lausi, Andrea, E-mail: andrea.lausi@elettra.trieste.it [Sincrotrone Trieste S.C.p.A., ss 14, km 163, 5, 34149 Basovizza, Trieste (Italy); Plaisier, Jasper, E-mail: jasper.plaisier@elettra.trieste.it [Sincrotrone Trieste S.C.p.A., ss 14, km 163, 5, 34149 Basovizza, Trieste (Italy)

    2012-06-15T23:59:59.000Z

    The structural determination of the CeO{sub 2}/Gd{sub 2}O{sub 3} mixed system is a non-trivial problem because of the close resemblance between the ionic sizes of Ce{sup 4+} and Gd{sup 3+} and between the crystal structures of CeO{sub 2} and Gd{sub 2}O{sub 3}. (Ce{sub 1-x}Gd{sub x})O{sub 2-x/2} powder samples with x ranging between 0 and 1 have been synthesized by coprecipitation of mixed oxalates and subsequent thermal decomposition in air at 1200 Degree-Sign C followed by slow cooling. Synchrotron powder X-ray diffraction data were collected and refined by the Rietveld method. Lattice parameters do not follow Vegard's law and no peak splitting has been observed for any composition, meaning that no biphasic regions exist over the whole compositional range. The same hybrid structural model - a proper mixture of the structures of the two pure oxides - was used for the refinements, allowing to account for the data observed. - graphical abstract: Substituting Ce{sup 4+} by Gd{sup 3+}, a gradual transition from the F structure (typical of CeO{sub 2}) to the C structure (typical of Gd{sub 2}O{sub 3}) takes place. The lattice parameters do not follow Vegard's law. Highlights: Black-Right-Pointing-Pointer A structural study of Ce-Gd mixed oxides has been performed. Black-Right-Pointing-Pointer In (Ce{sub 1-x}Gd{sub x})O{sub 2-x/2} a solid solution forms for 0{<=}x{<=}0.3. Black-Right-Pointing-Pointer For x>0.3 a gradual transition from the C to the F structure is observed. Black-Right-Pointing-Pointer Lattice parameters do not follow Vegard's law.

  8. Time-resolved synchrotron x-ray diffraction studies of the crystallization of amorphous Co(80-x)FexB??

    SciTech Connect (OSTI)

    Simmons, L. M., E-mail: l.simmons@mmu.ac.uk [Division of Electrical and Electronic Engineering, School of Engineering, Manchester Metropolitan University, Manchester M1 5GD (United Kingdom); Greig, D. [School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT (United Kingdom); Lucas, C. A. [Oliver Lodge Laboratory, Department of Physics, University of Liverpool, Liverpool L69 7ZE (United Kingdom); Kilcoyne, S. H. [School of Applied Sciences, University of Huddersfield, Huddersfield HD1 3DH (United Kingdom)

    2014-09-28T23:59:59.000Z

    This paper addresses the time-dependent crystallization process occurring in “bulk” amorphous Co(80-x)FexB?? (x = 20, 40) metallic ribbons by means of synchrotron x-ray diffraction (SXRD) and transmission electron microscopy. Metallic ribbons, produced via melt-spinning technique, were annealed in-situ, with SXRD patterns collected every 60 s. SXRD reveals that Co??Fe??B?? alloys crystallize from an amorphous structure to a primary bcc ?-(Co,Fe) phase, whereas Co??Fe??B?? initially crystallizes into the same bcc ?-(Co,Fe) but exhibits cooperative growth of both stable and metastable boride phases later into the hold. Johnson-Mehl-Avrami-Kolmogorov statistics was used on post annealed samples to determine the mechanisms of growth and the activation energy (Ea) of the ?-(Co,Fe) phase. Results indicate that the growth mechanisms are similar for both alloy compositions for all annealing temperatures, with the Avrami exponent of n = 1.51(1) and 2.02(6) for x = 20 and 40, respectively, suggesting one-dimensional growth, with a decreasing nucleation rate. Activation energy for ?-(Co,Fe) was determined to be 2.7(1) eV and 2.4(3) eV in x = 20 and 40, respectively, suggesting that those alloys with a lower Co content have a stronger resistance to crystallization. Based on these results, fabrication of CoFeB magnetic tunnel junctions via depositing amorphous layers and subsequently annealing to induce lattice matching presents itself as a viable and efficient method, for increasing the giant magnetoresistance in magnetic tunnel junctions.

  9. Hidden Superlattice in Tl2(SC6H4S) and Tl2(SeC6H4Se) Solved from Powder X-ray Diffraction

    SciTech Connect (OSTI)

    K Stone; D Turner; M Singh; T Vaid; P Stephens

    2011-12-31T23:59:59.000Z

    The crystal structures of the isostructural title compounds poly[({mu}-benzene-1,4-dithiolato)dithallium], Tl{sub 2}(SC{sub 6}H{sub 4}S), and poly[({mu}-benzene-1,4-diselenolato)dithallium], Tl{sub 2}(SeC{sub 6}H{sub 4}Se), were solved by simulated annealing from high-resolution synchrotron X-ray powder diffraction. Rietveld refinements of an initial structure with one formula unit per triclinic cell gave satisfactory agreement with the data, but led to a structure with impossibly close non-bonded contacts. A disordered model was proposed to alleviate this problem, but an alternative supercell structure leads to slightly improved agreement with the data. The isostructural superlattice structures were confirmed for both compounds through additional data collection, with substantially better counting statistics, which revealed the presence of very weak superlattice peaks not previously seen. Overall, each structure contains Tl-S or Tl-Se two-dimensional networks, connected by phenylene bridges. The sulfur (or selenium) coordination sphere around each thallium is a highly distorted square pyramid or a 'see-saw' shape, depending upon how many Tl-S or Tl-Se interactions are considered to be bonds. In addition, the two compounds contain pairs of Tl{sup I} ions that interact through a closed-shell 'thallophilic' interaction: in the sulfur compound there are two inequivalent pairs of Tl atoms with Tl-Tl distances of 3.49 and 3.58 {angstrom}, while in the selenium compound those Tl-Tl interactions are at 3.54 and 3.63 {angstrom}.

  10. Spectroscopic and X-ray diffraction investigation of the behavior of hanksite and tychite at high pressures, and a model for the compressibility of sulfate minerals

    E-Print Network [OSTI]

    Palaich, SEM; Manning, CE; Schauble, E; Kavner, A

    2013-01-01T23:59:59.000Z

    Physics and Chemistry of Minerals, 37, 5, 265–282. Chen,and Smith, G.I. (1965) Mineral equilibria in the Searlesstudy of the behavior of mineral barite by X?ray dif-

  11. E-Print Network 3.0 - aspect ratio x-ray Sample Search Results

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    0953-89841825S17 Summary: the power ratio of beam splitting. With centralized remote control, heating and x-ray diffraction... for in situ x-ray diffraction at high...

  12. X-ray diffraction on the X-cut of a Ca{sub 3}TaGa{sub 3}Si{sub 2}O{sub 14} single crystal modulated by a surface acoustic wave

    SciTech Connect (OSTI)

    Irzhak, D., E-mail: irzhak@iptm.ru; Roshchupkin, D., E-mail: rochtch@iptm.ru [Institute of Microelectronics Technology and High-Purity Materials Russian Academy of Sciences, Chernogolovka 142432 (Russian Federation)

    2014-06-28T23:59:59.000Z

    The result of X-ray diffraction study on a single crystal of the calcium-gallogermanate family Ca{sub 3}TaGa{sub 3}Si{sub 2}O{sub 14} (CTGS) modulated by a surface acoustic wave (SAW) is presented. The power flow angle for SAW propagating along the X{sub 2} axis of the X-cut in CTGS was measured. The rocking curves for the CTGS crystal were recorded at different amplitudes of an input high frequency electric signal on interdigital transducer used to excite a SAW. Based on the data obtained, intensity dependence of diffraction satellites on the amplitude of electric signal exciting a SAW was built. Numerical simulation of the crystal rocking curves and dependence of diffraction satellite intensities on the SAW amplitude enabled the selection of a set of material constants at which the most complete coincidence of experimental and calculated results is observed.

  13. Chest x-Rays

    Broader source: Energy.gov [DOE]

    The B-reading is a special reading of a standard chest x-ray film performed by a physician certified by the National Institute for Occupational Safety and Health (NIOSH). The reading looks for changes on the chest x-ray that may indicate exposure and disease caused by agents such as asbestos or silica.

  14. Quantum Model of Catalysis Based on a Mobile Proton Revealed by Subatomic X-ray and Neutron Diffraction Studies of h-aldose Reductase

    SciTech Connect (OSTI)

    Blakeley, M. P. [European Molecular Biology Laboratory (EMBL), France; Ruiz, Fredrico [Institut de Genetique et de Biologie Moleculaire et Cellulaire, CNRS, ULP, INSER; Cachau, Raul [SAIC-Frederick, Inc., National Cancer Institute at Frederick, Frederick, MD; Hazemann, I. [Institut Laue-Langevin (ILL); Meilleur, Flora [Institut Laue-Langevin (ILL); Mitschler, A. [IGBMC; Ginell, Stephan [Argonne National Laboratory (ANL); Afonine, Pavel [Lawrence Berkeley National Laboratory (LBNL); Ventura, Oscar [Computational Chemical Physics Group, DETEMA, Facultad de Quimica, UdelaR, C.C.1; Cousido-Siah, Alexandra [Institut de Genetique et de Biologie Moleculaire et Cellulaire, CNRS, ULP, INSER; Haertlein, M. [Institut Laue-Langevin (ILL); Joachimiak, Andrzej [Argonne National Laboratory (ANL); Myles, Dean A A [ORNL; Podjarny, A. [IGBMC

    2008-01-01T23:59:59.000Z

    We present results of combined studies of the enzyme human aldose reductase (h-AR, 36 kDa) using single-crystal x-ray data (0.66 Angstroms, 100K; 0.80 Angstroms, 15K; 1.75 Angstroms, 293K), neutron Laue data (2.2 Angstroms, 293K), and quantum mechanical modeling. These complementary techniques unveil the internal organization and mobility of the hydrogen bond network that defines the properties of the catalytic engine, explaining how this promiscuous enzyme overcomes the simultaneous requirements of efficiency and promiscuity offering a general mechanistic view for this class of enzymes.

  15. Proceedings of the workshop on X-ray computed microtomography

    SciTech Connect (OSTI)

    NONE

    1998-02-01T23:59:59.000Z

    This report consists of vugraphs from the nine presentations at the conference. Titles of the presentations are: CMT: Applications and Techniques; Computer Microtomography Using X-rays from Third Generation Synchrotron X-ray; Approaches to Soft-X-ray Nanotomography; Diffraction Enhanced Tomography; X-ray Computed Microtomography Applications at the NSLS; XCMT Applications in Forestry and Forest Products; 3DMA: Investigating Three Dimensional Pore Geometry from High Resolution Images; X-ray Computed Microtomography Studies of Volcanic Rock; and 3-D Visualization of Tomographic Volumes.

  16. Theoretical standards in x-ray spectroscopies

    SciTech Connect (OSTI)

    Not Available

    1992-01-01T23:59:59.000Z

    We propose to extend our state-of-the-art, ab initio XAFS (X-ray absorption fine structure) codes, FEFF. Our current work has been highly successful in achieving accurate, user-friendly XAFS standards, exceeding the performance of both tabulated standards and other codes by a considerable margin. We now propose to add the capability to treat more complex materials. This includes multiple-scattering, polarization dependence, an approximate treatment of XANES (x-ray absorption near edge structure), and other improvements. We also plan to adapt FEFF to other spectroscopies, e.g. photoelectron diffraction (PD) and diffraction anomalous fine structure (DAFS).

  17. X-ray laser

    DOE Patents [OSTI]

    Nilsen, Joseph (Livermore, CA)

    1991-01-01T23:59:59.000Z

    An X-ray laser (10) that lases between the K edges of carbon and oxygen, i.e. between 44 and 23 Angstroms, is provided. The laser comprises a silicon (12) and dysprosium (14) foil combination (16) that is driven by two beams (18, 20) of intense line focused (22, 24) optical laser radiation. Ground state nickel-like dysprosium ions (34) are resonantly photo-pumped to their upper X-ray laser state by line emission from hydrogen-like silicon ions (32). The novel X-ray laser should prove especially useful for the microscopy of biological specimens.

  18. Ray tracing flux calculation for the small and wide angle x-ray scattering diffraction station at the SESAME synchrotron radiation facility

    SciTech Connect (OSTI)

    Salah, Wa'el [Synchrotron-light for Experimental Science and Application in the Middle East (SESAME), P.O. Box 7, Allan 19252 (Jordan); Department of Physics, The Hashemite University, Zarqa 13115 (Jordan); Sanchez del Rio, M. [European Synchrotron Radiation Facility, Bp 220, 38043 Grenoble Cedex (France); Hoorani, H. [Synchrotron-light for Experimental Science and Application in the Middle East (SESAME), P.O. Box 7, Allan 19252 (Jordan)

    2009-09-15T23:59:59.000Z

    The calculation for the optics of the synchrotron radiation small and wide angle x-ray scattering beamline, currently under construction at SESAME is described. This beamline is based on a cylindrically bent germanium (111) single crystal with an asymmetric cut of 10.5 deg., followed by a 1.2 m long rhodium coated plane mirror bent into a cylindrical form. The focusing properties of bent asymmetrically cut crystals have not yet been studied in depth. The present paper is devoted to study of a particular application of a bent asymmetrically cut crystal using ray tracing simulations with the SHADOW code. These simulations show that photon fluxes of order of 1.09x10{sup 11} photons/s will be available at the experimental focus at 8.79 keV. The focused beam dimensions will be 2.2 mm horizontal full width at half maximum (FWHM) by 0.12 mm vertical (FWHM).

  19. Ultra-short wavelength x-ray system

    DOE Patents [OSTI]

    Umstadter, Donald (Ann Arbor, MI); He, Fei (Ann Arbor, MI); Lau, Yue-Ying (Potomac, MD)

    2008-01-22T23:59:59.000Z

    A method and apparatus to generate a beam of coherent light including x-rays or XUV by colliding a high-intensity laser pulse with an electron beam that is accelerated by a synchronized laser pulse. Applications include x-ray and EUV lithography, protein structural analysis, plasma diagnostics, x-ray diffraction, crack analysis, non-destructive testing, surface science and ultrafast science.

  20. Absence of Structural Impact of Noble Nanoparticles on P3HT: PCBM Blends for Plasmon Enhanced Bulk-Heterojunction Organic Solar Cells Probed by Synchrotron Grazing Incidence X-Ray Diffraction

    E-Print Network [OSTI]

    Samuele Lilliu; Mejd Alsari; Oier Bikondoa; J. Emyr Macdonald; Marcus S. Dahlem

    2014-10-18T23:59:59.000Z

    The incorporation of noble metal nanoparticles, displaying localized surface plasmon resonance, in the active area of donor-acceptor bulk-heterojunction organic photovoltaic devices is an industrially compatible light trapping strategy, able to guarantee better absorption of the incident photons and give an efficiency improvement between 12% and 38%. In the present work, we investigate the effect of Au and Ag nanoparticles blended with P3HT: PCBM on the P3HT crystallization dynamics by synchrotron grazing incidence X-ray diffraction. We conclude that the presence of (1) 80nm Au, (2) mix of 5nm, 50nm, 80nm Au, (3) 40nm Ag, and (4) 10nm, 40nm, 60nm Ag colloidal nanoparticles, at different concentrations below 0.3 wt% in P3HT: PCBM blends, does not affect the behaviour of the blends themselves.

  1. X-Ray diffraction and vibrational spectroscopic study of 2-chloro-N-{l_brace}4-[3-(2,5-dimethylphenyl)-3-methylcyclobutyl] -thiazol-2-yl{r_brace}-acetamide

    SciTech Connect (OSTI)

    Caliskan, Nezihe, E-mail: nezihec@omu.edu.tr; Guentepe, Feyizan [Ondokuz Mayis University, Department of Physics, Faculty of Arts and Sciences (Turkey); Yueksektepe, Cigdem [Cankiri Karatekin University, Department of Physics, Faculty of Science (Turkey); Cukurovali, Alaaddin [Firat University, Department of Chemistry, Faculty of Science (Turkey); Bueyuekguengoer, Orhan [Ondokuz Mayis University, Department of Physics, Faculty of Arts and Sciences (Turkey)

    2010-12-15T23:59:59.000Z

    The title compound C{sub 18}H{sub 21}ClN{sub 2}SO crystallizes with Z = 4 in space group P2{sub 1}/c. The structure of the title compound was characterized by {sup 1}H-NMR, {sup 13}C-NMR, IR and single crystal diffraction. There are an intermolecular N-H-O hydrogen bond and a C-H-{pi} interactions in crystal packing. In addition to the molecular geometry and packing obtained from X-ray experiment, the molecular geometry and vibrational frequencies of the title compound in ground state have been calculated using density functional theory method DFT (B3LYP) with 6-31G (d, p) basis set. Calculated frequencies, bond lengths, angles and dihedral angles are in good agreement with the corresponding experimental data.

  2. Development of procedures for refurbishing x-ray optics at the Advanced Light Source

    E-Print Network [OSTI]

    Yashchuk, Valeriy V.

    2013-01-01T23:59:59.000Z

    and Setting of Bendable Optics for Diffraction- Limitedof Soft X-Rays,” Abstract to SPIE Optics and Photonics 2012,Metrology for X-Ray and EUV Optics IV (San Diego, August 12-

  3. Development of at-wavelength metrology for x-ray optics at the ALS

    E-Print Network [OSTI]

    Yashchuk, Valeriy V.

    2010-01-01T23:59:59.000Z

    alignment of bendable x-ray optics to realize diffraction-Bass (Ed. ), Handbook of Optics, third ed. , vol. V, ch. 46,wavelength metrology for x-ray optics at the ALS* Valeriy V.

  4. Lensless Imaging of Whole Biological Cells with Soft X-Rays

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Lensless Imaging of Whole Biological Cells with Soft X-Rays Print A team of scientists has used x-ray diffraction microscopy at ALS Beamline 9.0.1 to make images of whole yeast...

  5. In situ synchrotron based x-ray techniques as monitoring tools for atomic layer deposition

    SciTech Connect (OSTI)

    Devloo-Casier, Kilian, E-mail: Kilian.DevlooCasier@Ugent.be; Detavernier, Christophe; Dendooven, Jolien [Department of Solid State Sciences, Ghent University, Krijgslaan 281/S1, B-9000 Ghent (Belgium); Ludwig, Karl F. [Physics Department, Boston University, 590 Commonwealth Avenue, Boston, Massachusetts 02215 (United States)

    2014-01-15T23:59:59.000Z

    Atomic layer deposition (ALD) is a thin film deposition technique that has been studied with a variety of in situ techniques. By exploiting the high photon flux and energy tunability of synchrotron based x-rays, a variety of new in situ techniques become available. X-ray reflectivity, grazing incidence small angle x-ray scattering, x-ray diffraction, x-ray fluorescence, x-ray absorption spectroscopy, and x-ray photoelectron spectroscopy are reviewed as possible in situ techniques during ALD. All these techniques are especially sensitive to changes on the (sub-)nanometer scale, allowing a unique insight into different aspects of the ALD growth mechanisms.

  6. Characterization of Ni/Al multilayer on Si substrate by diffraction and reflectometry techniques

    SciTech Connect (OSTI)

    Swain, Mitali; Basu, Saibal; Bhattacharya, Debarati; Gupta, Mukul [Solid State Physics Division Bhabha Atomic Research Center, Mumbai 400085 (India); UGC-DAE-Consortium for Scientific Research, University Campus, Khandwa Road, Indore 452017 (India)

    2012-06-05T23:59:59.000Z

    An ion beam deposited multilayer film of nominal thickness [Ni(200 Angst )/Al(100 Angst )]x5 on Si substrate has been characterized by X-Ray Diffraction(XRD), X-Ray Reflectivity (XRR) and Polarized neutron reflectivity(PNR). The present paper attempts to identify presence of any intermetallic compounds at the interfaces of the as-deposited sample. Structural parameters obtained from XRR and PNR are close to design values.

  7. Femtosecond X-ray protein nanocrystallography

    SciTech Connect (OSTI)

    Chapman, Henry N.; Fromme, Petra; Barty, Anton; White, Thomas A.; Kirian, Richard A.; Aquila, Andrew; Hunter, Mark S.; Schulz, Joachim; DePonte, Daniel P.; Weierstall, Uwe; Doak, R. Bruce; Maia, Filipe R. N. C.; Martin, Andrew V.; Schlichting, Ilme; Lomb, Lukas; Coppola, Nicola; Shoeman, Robert L.; Epp, Sascha W.; Hartmann, Robert; Rolles, Daniel; Rudenko, Artem; Foucar, Lutz; Kimmel, Nils; Weidenspointner, Georg; Holl, Peter; Liang, Mengning; Barthelmess, Miriam; Caleman, Carl; Boutet, Sebastien; Bogan, Michael J.; Krzywinski, Jacek; Bostedt, Christoph; Bajt, Sasa; Gumprecht, Lars; Rudek, Benedikt; Erk, Benjamin; Schmidt, Carlo; Homke, Andre; Reich, Christian; Pietschner, Daniel; Struder, Lothar; Hauser, Gunter; Gorke, Hubert; Ullrich, Joachim; Herrmann, Sven; Schaller, Gerhard; Schopper, Florian; Soltau, Heike; Kuhnel, Kai-Uwe; Messerschmidt, Marc; Bozek, John D.; Hau-Riege, Stefan P.; Frank, Matthias; Hampton, Christina Y.; Sierra, Raymond G.; Starodub, Dmitri; Williams, Garth J.; Hajdu, Janos; Timneanu, Nicusor; Seibert, M. Marvin; Andreasson, Jakob; Rocker, Andrea; Jonsson, Olof; Svenda, Martin; Stern, Stephan; Nass, Karol; Andritschke, Robert; Schroter, Claus-Dieter; Krasniqi, Faton; Bott, Mario; Schmidt, Kevin E.; Wang, Xiaoyu; Grotjohann, Ingo; Holton, James M.; Barends, Thomas R. M.; Neutze, Richard; Marchesini, Stefano; Fromme, Raimund; Schorb, Sebastian; Rupp, Daniela; Adolph, Marcus; Gorkhover, Tais; Andersson, Inger; Hirsemann, Helmut; Potdevin, Guillaume; Graafsma, Heinz; Nilsson, Bjorn; Spence, John C. H.

    2011-01-01T23:59:59.000Z

    X-ray crystallography provides the vast majority of macromolecular structures, but the success of the method relies on growing crystals of sufficient size. In conventional measurements, the necessary increase in X-ray dose to record data from crystals that are too small leads to extensive damage before a diffraction signal can be recorded. It is particularly challenging to obtain large, well-diffracting crystals of membrane proteins, for which fewer than 300 unique structures have been determined despite their importance in all living cells. Here we present a method for structure determination where single-crystal X-ray diffraction ‘snapshots’ are collected from a fully hydrated stream of nanocrystals using femtosecond pulses from a hard-X-ray free-electron laser, the Linac Coherent Light Source. We prove this concept with nanocrystals of photosystem I, one of the largest membrane protein complexes. More than 3,000,000 diffraction patterns were collected in this study, and a three-dimensional data set was assembled from individual photosystem I nanocrystals (~200?nm to 2??m in size). We mitigate the problem of radiation damage in crystallography by using pulses briefer than the timescale of most damage processes. This offers a new approach to structure determination of macromolecules that do not yield crystals of sufficient size for studies using conventional radiation sources or are particularly sensitive to radiation damage.

  8. X-ray beam finder

    DOE Patents [OSTI]

    Gilbert, H.W.

    1983-06-16T23:59:59.000Z

    An X-ray beam finder for locating a focal spot of an X-ray tube includes a mass of X-ray opaque material having first and second axially-aligned, parallel-opposed faces connected by a plurality of substantially identical parallel holes perpendicular to the faces and a film holder for holding X-ray sensitive film tightly against one face while the other face is placed in contact with the window of an X-ray head.

  9. X-Ray Diagnostics

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of ScienceandMesa del SolStrengtheningWildfires may contribute more toConsensusX-Ray Diagnostics X-Ray

  10. Crystallization and preliminary X-ray diffraction studies of tetrameric malate dehydrogenase from the novel Antarctic psychrophile Flavobacterium frigidimaris KUC-1

    SciTech Connect (OSTI)

    Fujii, Tomomi [Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011 (Japan); Oikawa, Tadao; Muraoka, Ikuo [Department of Life Science and Biotechnology, Faculty of Chemistry, Materials and Bioengineering, Kansai University, Suita, Osaka 564-8680 (Japan); Soda, Kenji [Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011 (Japan); Department of Life Science and Biotechnology, Faculty of Chemistry, Materials and Bioengineering, Kansai University, Suita, Osaka 564-8680 (Japan); Hata, Yasuo, E-mail: hata@scl.kyoto-u.ac.jp [Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011 (Japan)

    2007-11-01T23:59:59.000Z

    A psychrophilic malate dehydrogenase from the novel Antarctic bacterium F. frigidimaris KUC-1 was crystallized using the hanging-drop vapour-diffusion method. The crystals contained one tetrameric molecule per asymmetric unit. The best crystal diffracted to 1.8 Å resolution. Flavobacterium frigidimaris KUC-1 is a novel psychrotolerant bacterium isolated from Antarctic seawater. Malate dehydrogenase (MDH) is an essential metabolic enzyme in the citric acid cycle and has been cloned, overexpressed and purified from F. frigidimaris KUC-1. In contrast to the already known dimeric form of MDH from the psychrophile Aquaspirillium arcticum, F. frigidimaris MDH exists as a tetramer. It was crystallized at 288 K by the hanging-drop vapour-diffusion method using ammonium sulfate as the precipitating agent. The crystal diffracted to a maximum resolution of 1.80 Å. It contains one tetrameric molecule in the asymmetric unit.

  11. X-ray imaging crystal spectrometer for extended X-ray sources

    DOE Patents [OSTI]

    Bitter, Manfred L. (Princeton, NJ); Fraenkel, Ben (Jerusalem, IL); Gorman, James L. (Bordentown, NJ); Hill, Kenneth W. (Lawrenceville, NJ); Roquemore, A. Lane (Cranbury, NJ); Stodiek, Wolfgang (Princeton, NJ); von Goeler, Schweickhard E. (Princeton, NJ)

    2001-01-01T23:59:59.000Z

    Spherically or toroidally curved, double focusing crystals are used in a spectrometer for X-ray diagnostics of an extended X-ray source such as a hot plasma produced in a tokomak fusion experiment to provide spatially and temporally resolved data on plasma parameters using the imaging properties for Bragg angles near 45. For a Bragg angle of 45.degree., the spherical crystal focuses a bundle of near parallel X-rays (the cross section of which is determined by the cross section of the crystal) from the plasma to a point on a detector, with parallel rays inclined to the main plain of diffraction focused to different points on the detector. Thus, it is possible to radially image the plasma X-ray emission in different wavelengths simultaneously with a single crystal.

  12. Soft x-ray reduction camera for submicron lithography

    DOE Patents [OSTI]

    Hawryluk, Andrew M. (2708 Rembrandt Pl., Modesto, CA 95356); Seppala, Lynn G. (7911 Mines Rd., Livermore, CA 94550)

    1991-01-01T23:59:59.000Z

    Soft x-ray projection lithography can be performed using x-ray optical components and spherical imaging lenses (mirrors), which form an x-ray reduction camera. The x-ray reduction is capable of projecting a 5x demagnified image of a mask onto a resist coated wafer using 4.5 nm radiation. The diffraction limited resolution of this design is about 135 nm with a depth of field of about 2.8 microns and a field of view of 0.2 cm.sup.2. X-ray reflecting masks (patterned x-ray multilayer mirrors) which are fabricated on thick substrates and can be made relatively distortion free are used, with a laser produced plasma for the source. Higher resolution and/or larger areas are possible by varying the optic figures of the components and source characteristics.

  13. Soft x-ray reduction camera for submicron lithography

    DOE Patents [OSTI]

    Hawryluk, A.M.; Seppala, L.G.

    1991-03-26T23:59:59.000Z

    Soft x-ray projection lithography can be performed using x-ray optical components and spherical imaging lenses (mirrors), which form an x-ray reduction camera. The x-ray reduction is capable of projecting a 5x demagnified image of a mask onto a resist coated wafer using 4.5 nm radiation. The diffraction limited resolution of this design is about 135 nm with a depth of field of about 2.8 microns and a field of view of 0.2 cm[sup 2]. X-ray reflecting masks (patterned x-ray multilayer mirrors) which are fabricated on thick substrates and can be made relatively distortion free are used, with a laser produced plasma for the source. Higher resolution and/or larger areas are possible by varying the optic figures of the components and source characteristics. 9 figures.

  14. Scattering of x rays from low-Z materials

    SciTech Connect (OSTI)

    Gaines, J.L.; Kissel, L.D.; Catron, H.C.; Hansen, R.A.

    1980-08-01T23:59:59.000Z

    X rays incident on thin beryllium, boron, carbon, and other low-Z materials undergo both elastic and inelastic scattering as well as diffraction from the crystalline or crystalline-like structure of the material. Unpolarized monoenergetic x rays in the 1.5 to 8.0-keV energy range were used to determine the absolute scattering efficiency of thin beryllium, carbon, and boron foils. These measurements are compared to calculated scattering efficiencies predicted by single-atom theories. In addition, the relative scattering efficiency versus x-ray energy was measured for other low-Z foils using unpolarized bremsstrahlung x rays. In all the low-Z foils examined, we observed Bragg-like x-ray diffraction due to the ordered structure of the materials.

  15. Direct Observations of the (Alpha to Gamma) Transformation at Different Input Powers in the Heat Affected Zone of 1045 C-Mn Steel Arc Welds Observed by Spatially Resolved X-Ray Diffraction

    SciTech Connect (OSTI)

    Palmer, T A; Elmer, J W

    2005-03-16T23:59:59.000Z

    Spatially Resolved X-Ray Diffraction (SRXRD) experiments have been performed during Gas Tungsten Arc (GTA) welding of AISI 1045 C-Mn steel at input powers ranging from 1000 W to 3750 W. In situ diffraction patterns taken at discreet locations across the width of the heat affected zone (HAZ) near the peak of the heating cycle in each weld show regions containing austenite ({gamma}), ferrite and austenite ({alpha}+{gamma}), and ferrite ({alpha}). Changes in input power have a demonstrated effect on the resulting sizes of these regions. The largest effect is on the {gamma} phase region, which nearly triples in width with increasing input power, while the width of the surrounding two phase {alpha}+{gamma} region remains relatively constant. An analysis of the diffraction patterns obtained across this range of locations allows the formation of austenite from the base metal microstructure to be monitored. After the completion of the {alpha} {yields} {gamma} transformation, a splitting of the austenite peaks is observed at temperatures between approximately 860 C and 1290 C. This splitting in the austenite peaks results from the dissolution of cementite laths originally present in the base metal pearlite, which remain after the completion of the {alpha} {yields} {gamma} transformation, and represents the formation of a second more highly alloyed austenite constituent. With increasing temperatures, carbon, originally present in the cementite laths, diffuses from the second newly formed austenite constituent to the original austenite constituent. Eventually, a homogeneous austenitic microstructure is produced at temperatures of approximately 1300 C and above, depending on the weld input power.

  16. Fluctuation X-Ray Scattering

    SciTech Connect (OSTI)

    Saldin, PI: D. K.; Co-I's: J. C. H. Spence and P. Fromme

    2013-01-25T23:59:59.000Z

    The work supported by the grant was aimed at developing novel methods of finding the structures of biomolecules using x-rays from novel sources such as the x-ray free electron laser and modern synchrotrons

  17. Tunable X-ray source

    DOE Patents [OSTI]

    Boyce, James R. (Williamsburg, VA)

    2011-02-08T23:59:59.000Z

    A method for the production of X-ray bunches tunable in both time and energy level by generating multiple photon, X-ray, beams through the use of Thomson scattering. The method of the present invention simultaneously produces two X-ray pulses that are tunable in energy and/or time.

  18. Phase transition upon K{sup +} ion exchange into Na-low silica X: Combined NMR and synchrotron X-ray powder diffraction study

    SciTech Connect (OSTI)

    Lee, Y.; Parise, J.B. [State Univ. of New York, Stony Brook, NY (United States)] [State Univ. of New York, Stony Brook, NY (United States); Carr, S.W. [ANSTO, Menai (Australia)] [ANSTO, Menai (Australia)

    1998-09-01T23:59:59.000Z

    The mechanism by which K{sup +} ions exchange into zeolite Na-low silica X (LSX) (Na{sub 96}Al{sub 96}Si{sub 96}O{sub 384}{center_dot}nH{sub 2}O) has ben determined by studying structures of the Na-LSX and K-LSX end members in the Na-K LSX solid solution series as well as samples exchanged at the 20%, 42% and 80% K{sup +} levels. A preliminary investigation using {sup 29}Si MAS NMR spectroscopy revealed a two-phase region in the solid solution near 80% K{sup +} exchange. Rietveld analysis of the powder diffraction data collected from hydrated samples showed that, up to 42% of K{sup +} exchange, K{sup +} ions were located preferentially at site I{prime}, just outside the double 6-ring (D6R) in the sodalite age, and at site II, above the single 6-ring (S6R) in the supercage. Introduction of K{sup +} ions into site I{prime} repositioned Na{sup +} ions into site I, at the center of the D6R. An abrupt change in the cubic lattice parameter from 25.0389(5) to 25.2086(5) {angstrom} marked the formation of a second phase at the 80% K{sup +}-exchange level as K{sup +} ions began to occupy site I. No coexistence of phases was observed for the fully K{sup +}-exchanged sample (a = 25.2486(2) {angstrom}), where sites I and II were fully occupied by K{sup +} ions.

  19. Synthesis and single-crystal X-ray diffraction studies of new framework substituted type II clathrates, Cs{sub 8}Na{sub 16}Ag{sub x}Ge{sub 136-x} (x<7)

    SciTech Connect (OSTI)

    Beekman, M. [Department of Physics, University of South Florida, 4202 East Fowler Ave., PHY 114, Tampa, FL 33620 (United States); Wong-Ng, W. [Materials Science and Engineering Laboratory, National Institute of Standards and Technology, Gaithersburg, MD 20899 (United States); Kaduk, J.A. [INEOS Technologies, Naperville, IL 60566 (United States); Shapiro, A. [Materials Science and Engineering Laboratory, National Institute of Standards and Technology, Gaithersburg, MD 20899 (United States); Nolas, G.S. [Department of Physics, University of South Florida, 4202 East Fowler Ave., PHY 114, Tampa, FL 33620 (United States)], E-mail: gnolas@cas.usf.edu

    2007-03-15T23:59:59.000Z

    New inorganic type II clathrates with Ag atoms substituting for framework Ge atoms, Cs{sub 8}Na{sub 16}Ag{sub x}Ge{sub 136-x} (x=0, 5.9, and 6.7), have been synthesized by reaction of the pure elements at high temperature. Structural refinements have been performed using single crystal X-ray diffraction. The materials crystallize with the cubic type II clathrate crystal structure (space group Fd3-barm) with a=15.49262(9)A, 15.51605(6)A, and 15.51618(9) for x=0, 5.9, and 6.7, respectively, and Z=1. The structure is formed by a covalently bonded Ag-Ge framework, in which the Cs and Na atoms are found inside two types of polyhedral cages. Ag substitutes for Ge in the tetrahedrally bonded framework positions, and was found to preferentially occupy the most asymmetric 96g site. The proven ability to substitute atoms for the germanium framework should offer a route to the synthesis of new compositions of type II clathrates, materials that are of interest for potential thermoelectrics applications.

  20. High-pressure x-ray diffraction study of YBO{sub 3}/Eu{sup 3+}, GdBO{sub 3}, and EuBO{sub 3}: Pressure-induced amorphization in GdBO{sub 3}

    SciTech Connect (OSTI)

    Wang, Pei; Xu, Chao; Ren, Xiangting; Lei, Li; Wang, Shanmin; Peng, Fang; Yan, Xiaozhi; Liu, Dongqiong; Wang, Qiming [Institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610065 (China); He, Duanwei, E-mail: duanweihe@scu.edu.cn [Institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610065 (China); Institute of Fluid Physics and National Key Laboratory of Shockwave and Detonation Physics, China Academy of Engineering Physics, Mianyang 621900 (China); Xiong, Lun; Liu, Jing [Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049 (China)

    2014-01-28T23:59:59.000Z

    Angle-dispersive synchrotron X-ray diffraction measurements were performed on vaterite-type YBO{sub 3}/Eu{sup 3+}, GdBO{sub 3}, and EuBO{sub 3}, respectively, up to 41?GPa at room temperature using a diamond-anvil cell. Pressure-induced amorphization was observed in hexagonal GdBO{sub 3} with a significant compression along the c-axis. Compared to the ions of the distorted GdBO{sub 3} phase, its anions may lose their long-range order prior to the cations at high pressures. Based on the experimental pressure-volume data, the obtained bulk moduli of YBO{sub 3}/Eu{sup 3+} and GdBO{sub 3} are 329 and 321?GPa, respectively, which are more than 90% larger than that of EuBO{sub 3} (167?GPa) and are presumably attributed to Gd{sup 3+} and Y{sup 3+} with a high density of d valence electrons.

  1. The nature of marbled Terra Sigillata slips: a combined mu XRF and mu XRD investigation

    E-Print Network [OSTI]

    Leon, Yoanna

    2009-01-01T23:59:59.000Z

    Sigillata slips: a combined µXRF and µXRD investigation Y.and micro x-ray fluorescence (µXRF), as it makes correlationthe highest quality µXRD and µXRF measurements we decided to

  2. X-ray lithography source

    DOE Patents [OSTI]

    Piestrup, Melvin A. (Woodside, CA); Boyers, David G. (Mountain View, CA); Pincus, Cary (Sunnyvale, CA)

    1991-01-01T23:59:59.000Z

    A high-intensity, inexpensive X-ray source for X-ray lithography for the production of integrated circuits. Foil stacks are bombarded with a high-energy electron beam of 25 to 250 MeV to produce a flux of soft X-rays of 500 eV to 3 keV. Methods of increasing the total X-ray power and making the cross section of the X-ray beam uniform are described. Methods of obtaining the desired X-ray-beam field size, optimum frequency spectrum and elminating the neutron flux are all described. A method of obtaining a plurality of station operation is also described which makes the process more efficient and economical. The satisfying of these issues makes transition radiation an exellent moderate-priced X-ray source for lithography.

  3. X-ray lithography source

    DOE Patents [OSTI]

    Piestrup, M.A.; Boyers, D.G.; Pincus, C.

    1991-12-31T23:59:59.000Z

    A high-intensity, inexpensive X-ray source for X-ray lithography for the production of integrated circuits is disclosed. Foil stacks are bombarded with a high-energy electron beam of 25 to 250 MeV to produce a flux of soft X-rays of 500 eV to 3 keV. Methods of increasing the total X-ray power and making the cross section of the X-ray beam uniform are described. Methods of obtaining the desired X-ray-beam field size, optimum frequency spectrum and eliminating the neutron flux are all described. A method of obtaining a plurality of station operation is also described which makes the process more efficient and economical. The satisfying of these issues makes transition radiation an excellent moderate-priced X-ray source for lithography. 26 figures.

  4. X-ray spectrometry

    SciTech Connect (OSTI)

    Markowicz, A.A.; Van Grieken, R.E.

    1986-04-01T23:59:59.000Z

    In the period under review, i.e, through 1984 and 1985, some 600 articles on XRS (X-ray spectrometry) were published; most of these have been scanned and the most fundamental ones are discussed. All references will refer to English-language articles, unless states otherwise. Also general books have appeared on quantitative EPXMA (electron-probe X-ray microanalysis) and analytical electron microscopy (AEM) as well as an extensive review on the application of XRS to trace analysis of environmental samples. In the period under review no radically new developments have been seen in XRS. However, significant improvements have been made. Gain in intensities has been achieved by more efficient excitation, higher reflectivity of dispersing media, and better geometry. Better understanding of the physical process of photon- and electron-specimen interactions led to complex but more accurate equations for correction of various interelement effects. Extensive use of micro- and minicomputers now enables fully automatic operation, including qualitative analysis. However, sample preparation and presentation still put a limit to further progress. Although some authors find XRS in the phase of stabilization or even stagnation, further gradual developments are expected, particularly toward more dedicated equipment, advanced automation, and image analysis systems. Ways are outlined in which XRS has been improved in the 2 last years by excitation, detection, instrumental, methodological, and theoretical advances. 340 references.

  5. Miniature x-ray source

    DOE Patents [OSTI]

    Trebes, James E. (Livermore, CA); Stone, Gary F. (Livermore, CA); Bell, Perry M. (Tracy, CA); Robinson, Ronald B. (Modesto, CA); Chornenky, Victor I. (Minnetonka, MN)

    2002-01-01T23:59:59.000Z

    A miniature x-ray source capable of producing broad spectrum x-ray emission over a wide range of x-ray energies. The miniature x-ray source comprises a compact vacuum tube assembly containing a cathode, an anode, a high voltage feedthru for delivering high voltage to the anode, a getter for maintaining high vacuum, a connection for an initial vacuum pump down and crimp-off, and a high voltage connection for attaching a compact high voltage cable to the high voltage feedthru. At least a portion of the vacuum tube wall is highly x-ray transparent and made, for example, from boron nitride. The compact size and potential for remote operation allows the x-ray source, for example, to be placed adjacent to a material sample undergoing analysis or in proximity to the region to be treated for medical applications.

  6. Spectroscopic and Diffraction Study of Uranium Speciation in Contaminated Vadose Zone Sediments from the Hanford Site, Washington State

    SciTech Connect (OSTI)

    Catalano, Jeffrey G.; Heald, Steve M.; Zachara, John M.; Brown Jr., G E.

    2004-05-15T23:59:59.000Z

    Contamination of vadose zone sediments under tank BX-102 at the Hanford site, Washington, resulted from the accidental release of 7-8 metric tons of uranium dissolved in caustic aqueous sludge in 1951. We have applied synchrotron-based X-ray spectroscopic and diffraction techniques to characterize the speciation of uranium in samples of these contaminated sediments. U LIII-edge X-ray absorption fine structure (XAFS) spectroscopic studies demonstrate that uranium occurs predominantly as a uranium-(VI) silicate from the uranophane group of minerals. XAFS cannot distinguish between the members of this mineral group due to the near identical local coordination environments of uranium in these phases. However, these phases differ crystallographically, and can be distinguished using X-ray diffraction (XRD) methods. As the concentration of uranium was too low for conventional XRD to detect these phases, X-ray microdiffraction (?XRD) was used to collect diffraction patterns on {approx}20 ?m diameter areas of localized high uranium concentration found using microscanning X-ray fluorescence (?SXRF). Only sodium boltwoodite, Na(UO2)(SiO3OH)?1.5H2O, was observed; no other uranophane group minerals were present. Sodium boltwoodite formation has effectively sequestered uranium in these sediments under the current geochemical and hydrologic conditions. Attempts to remediate the uranium contamination will likely face significant difficulties because of the speciation and distribution of uranium in the sediments.

  7. Note: A novel normalization scheme for laser-based plasma x-ray sources

    SciTech Connect (OSTI)

    Zhang, B. B.; Sun, D. R.; Tao, Y., E-mail: taoy@ihep.ac.cn [Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049 (China); Sun, S. S. [Institute of Physics, Chinese Academy of Sciences, Beijing 100090 (China)

    2014-09-15T23:59:59.000Z

    A kHz repetition rate laser pump-X-ray probe system for ultrafast X-ray diffraction is set up based on a laser-driven plasma X-ray source. A simple and reliable normalization approach has been developed to minimize the impact of large X-ray pulse intensity fluctuation on data quality. It utilizes one single X-ray area detector to record both sample and reference signals simultaneously. Performance of this novel normalization method is demonstrated in reflectivity oscillation measurement of a superlattice sample at sub-ps resolution.

  8. Center for X-Ray Optics, 1992

    SciTech Connect (OSTI)

    Not Available

    1993-08-01T23:59:59.000Z

    This report discusses the following topics: Center for X-Ray Optics; Soft X-Ray Imaging wit Zone Plate Lenses; Biological X-Ray microscopy; Extreme Ultraviolet Lithography for Nanoelectronic Pattern Transfer; Multilayer Reflective Optics; EUV/Soft X-ray Reflectometer; Photoemission Microscopy with Reflective Optics; Spectroscopy with Soft X-Rays; Hard X-Ray Microprobe; Coronary Angiography; and Atomic Scattering Factors.

  9. Miniature x-ray source

    DOE Patents [OSTI]

    Trebes, James E. (Livermore, CA); Bell, Perry M. (Tracy, CA); Robinson, Ronald B. (Modesto, CA)

    2000-01-01T23:59:59.000Z

    A miniature x-ray source utilizing a hot filament cathode. The source has a millimeter scale size and is capable of producing broad spectrum x-ray emission over a wide range of x-ray energies. The miniature source consists of a compact vacuum tube assembly containing the hot filament cathode, an anode, a high voltage feedthru for delivering high voltage to the cathode, a getter for maintaining high vacuum, a connector for initial vacuum pump down and crimp-off, and a high voltage connection for attaching a compact high voltage cable to the high voltage feedthru. At least a portion of the vacuum tube wall is fabricated from highly x-ray transparent materials, such as sapphire, diamond, or boron nitride.

  10. Reciprocal space XRD mapping with varied incident angle as a probe of structure variation within surface depth

    SciTech Connect (OSTI)

    Yang, Qiguang [Norfolk State University; Williams, Frances [Norfolk State University; Zhao, Xin [JLAB; Reece, Charles E. [JLAB; Krishnan, Mahadevan [AASC, San Leandro, California

    2013-09-01T23:59:59.000Z

    In this study, we used a differential-depth X-Ray diffraction Reciprocal Spacing Mapping (XRD RSM) technique to investigate the crystal quality of a variety of SRF-relevant Nb film and bulk materials. By choosing different X-ray probing depths, the RSM study successfully revealed evolution the of materials? microstructure after different materials processes, such as energetic condensation or surface polishing. The RSM data clearly measured the materials? crystal quality at different thickness. Through a novel differential-depth RSM technique, this study found: I. for a heteroepitaxy Nb film Nb(100)/MgO(100), the film thickening process, via a cathodic arc-discharge Nb ion deposition, created a near-perfect single crystal Nb on the surface?s top-layer; II. for a mechanically polished single-crystal bulk Nb material, the microstructure on the top surface layer is more disordered than that in-grain.

  11. Lensless imaging of nanoporous glass with soft X-rays

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Turner, Joshua J.; Nelson, Johanna; Huang, Xiaojing; Steinbrener, Jan; Jacobsen, Chris

    2013-06-01T23:59:59.000Z

    Coherent soft X-ray diffraction has been used to image nanoporous glass structure in two dimensions using different methods. The merit of the reconstructions was judged using a new method of Fourier phase correlation with a final, refined image. The porous structure was found to have a much larger average size then previously believed.

  12. X-ray Absorption Spectroscopy of Transition Metal-Magnesium Hydride Thin Films

    E-Print Network [OSTI]

    X-ray Absorption Spectroscopy of Transition Metal-Magnesium Hydride Thin Films T. J. Richardsona@lbl.gov Abstract Mixed metal thin films containing magnesium and a first-row transition element exhibit very large of magnesium hydride. Keywords: A. hydrogen storage materials, thin films; C. EXAFS, NEXAFS, X-ray diffraction

  13. Compact x-ray source and panel

    DOE Patents [OSTI]

    Sampayon, Stephen E. (Manteca, CA)

    2008-02-12T23:59:59.000Z

    A compact, self-contained x-ray source, and a compact x-ray source panel having a plurality of such x-ray sources arranged in a preferably broad-area pixelized array. Each x-ray source includes an electron source for producing an electron beam, an x-ray conversion target, and a multilayer insulator separating the electron source and the x-ray conversion target from each other. The multi-layer insulator preferably has a cylindrical configuration with a plurality of alternating insulator and conductor layers surrounding an acceleration channel leading from the electron source to the x-ray conversion target. A power source is connected to each x-ray source of the array to produce an accelerating gradient between the electron source and x-ray conversion target in any one or more of the x-ray sources independent of other x-ray sources in the array, so as to accelerate an electron beam towards the x-ray conversion target. The multilayer insulator enables relatively short separation distances between the electron source and the x-ray conversion target so that a thin panel is possible for compactness. This is due to the ability of the plurality of alternating insulator and conductor layers of the multilayer insulators to resist surface flashover when sufficiently high acceleration energies necessary for x-ray generation are supplied by the power source to the x-ray sources.

  14. Stratigraphic correlation with X-ray powder patterns

    E-Print Network [OSTI]

    Singletary, John B

    1951-01-01T23:59:59.000Z

    pattern of maxima characteristic of all the principal spacings. For instance, if the radiation detector is set so as to observe the secondary diffracted beam at an angle which satisfies Bragg~s Law for some value of d found in the crystal, then a... focusing x-ray spectrometer manufac- tured by the North American Philips Company for commercial use. This instrument, shown in Fig. RB, consists of an x-ray generating unit, a goniometer, and a Geiger counter radiation detector. The patte ns were...

  15. Focused X-ray source

    DOE Patents [OSTI]

    Piestrup, M.A.; Boyers, D.G.; Pincus, C.I.; Maccagno, P.

    1990-08-21T23:59:59.000Z

    Disclosed is an intense, relatively inexpensive X-ray source (as compared to a synchrotron emitter) for technological, scientific, and spectroscopic purposes. A conical radiation pattern produced by a single foil or stack of foils is focused by optics to increase the intensity of the radiation at a distance from the conical radiator. 8 figs.

  16. Imaging X-ray Thomson Scattering Spectrometer Design and Demonstration

    SciTech Connect (OSTI)

    Gamboa, E.J. [University of Michigan; Huntington, C.M. [University of Michigan; Trantham, M.R. [University of Michigan; Keiter, P.A [University of Michigan; Drake, R.P. [University of Michigan; Montgomery, David [Los Alamos National Laboratory; Benage, John F. [Los Alamos National Laboratory; Letzring, Samuel A. [Los Alamos National Laboratory

    2012-05-04T23:59:59.000Z

    In many laboratory astrophysics experiments, intense laser irradiation creates novel material conditions with large, one-dimensional gradients in the temperature, density, and ionization state. X-ray Thomson scattering is a powerful technique for measuring these plasma parameters. However, the scattered signal has previously been measured with little or no spatial resolution, which limits the ability to diagnose inhomogeneous plasmas. We report on the development of a new imaging x-ray Thomson spectrometer (IXTS) for the Omega laser facility. The diffraction of x-rays from a toroidally-curved crystal creates high-resolution images that are spatially resolved along a one-dimensional profile while spectrally dispersing the radiation. This focusing geometry allows for high brightness while localizing noise sources and improving the linearity of the dispersion. Preliminary results are presented from a scattering experiment that used the IXTS to measure the temperature profile of a shocked carbon foam.

  17. Spatial resolution of synchrotron x-ray microtomography in high energy range: Effect of x-ray energy and sample-to-detector distance

    SciTech Connect (OSTI)

    Seo, D.; Tomizato, F.; Toda, H.; Kobayashi, M. [Department of Mechanical Engineering, Toyohashi University of Technology, Toyohashi, Aichi 441-8580 (Japan); Uesugi, K.; Takeuchi, A.; Suzuki, Y. [Japan Synchrotron Radiation Research Institute, Mikazuki, Sayo, Hyogo 679-5198 (Japan)

    2012-12-24T23:59:59.000Z

    Spatial resolution of three-dimensional images obtained by synchrotron X-ray microtomography technique is evaluated using cyclic bar patterns machined on a steel wire. Influences of X-ray energy and the sample-to-detector distance on spatial resolution were investigated. High X-ray energies of 33-78 keV are applied due to the high X-ray absorption of transition metals. Best spatial resolution of about 1.2 {mu}m pitch was observed at the sample-to-detector distance range of 20-110 mm and at the energy range of 68-78 keV. Several factors such as X-ray scattering and diffraction phenomena affecting the degradation of spatial resolution are also discussed.

  18. Deconvolving the temporal response of photoelectric x-ray detectors for the diagnosis of pulsed radiations

    SciTech Connect (OSTI)

    Zou, Shiyang; Song, Peng; Pei, Wenbing [Institute of Applied Physics and Computational Mathematics, Beijing 100094 (China)] [Institute of Applied Physics and Computational Mathematics, Beijing 100094 (China); Guo, Liang [Research Center of Laser Fusion, China Academy of Engineering Physics, P.O. Box 919-986, Mianyang 621900 (China)] [Research Center of Laser Fusion, China Academy of Engineering Physics, P.O. Box 919-986, Mianyang 621900 (China)

    2013-09-15T23:59:59.000Z

    Based on the conjugate gradient method, a simple algorithm is presented for deconvolving the temporal response of photoelectric x-ray detectors (XRDs) to reconstruct the resolved time-dependent x-ray fluxes. With this algorithm, we have studied the impact of temporal response of XRD on the radiation diagnosis of hohlraum heated by a short intense laser pulse. It is found that the limiting temporal response of XRD not only postpones the rising edge and peak position of x-ray pulses but also smoothes the possible fluctuations of radiation fluxes. Without a proper consideration of the temporal response of XRD, the measured radiation flux can be largely misinterpreted for radiation pulses of a hohlraum heated by short or shaped laser pulses.

  19. Producing X-rays at the APS

    ScienceCinema (OSTI)

    None

    2013-04-19T23:59:59.000Z

    An introduction and overview of the Advanced Photon Source at Argonne National Laboratory, the technology that produces the brightest X-ray beams in the Western Hemisphere, and the research carried out by scientists using those X-rays.

  20. Lensless X-Ray Imaging in Reflection

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    X-Ray Imaging in Reflection Print The advent of x-ray free-electron laser (XFEL) light sources has led to an outburst of research activities in the field of lensless imaging. XFELs...

  1. APS X-rays Reveal Picasso's Secret

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    | 2003 | 2002 | 2001 2000 Subscribe to APS News rss feed APS X-rays Reveal Picasso's Secret OCTOBER 15, 2012 Bookmark and Share X-rays reveal that Picasso's "Old Guitarist," at...

  2. Spectral analysis of X-ray binaries

    E-Print Network [OSTI]

    Fridriksson, Joel Karl

    2011-01-01T23:59:59.000Z

    In this thesis, I present work from three separate research projects associated with observations of X-ray binaries. Two of those revolve around spectral characteristics of neutron star low-mass X-ray binaries (NS-LMXBs), ...

  3. Soft x-ray diagnostics for pulsed power machines

    SciTech Connect (OSTI)

    Idzorek, G.C.; Coulter, W.L.; Walsh, P.J.; Montoya, R.R.

    1995-08-01T23:59:59.000Z

    A variety of soft x-ray diagnostics are being fielded on the Los Alamos National Laboratory Pegasus and Procyon pulsed power systems and also being fielded on joint US/Russian magnetized target fusion experiments known as MAGO (Magnitoye Obzhatiye). The authors have designed a low-cost modular photoemissive detector designated the XRD-96 that uses commercial 1100 series aluminum for the photocathode. In addition to photocathode detectors a number of designs using solid state silicon photodiodes have been designed and fielded. They also present a soft x-ray time-integrated pinhole camera system that uses standard type TMAX-400 photographic film that obviates the need for expensive and no longer produced zero-overcoat soft x-ray emulsion film. In a typical experiment the desired spectral energy cuts, signal intensity levels, and desired field of view will determine diagnostic geometry and x-ray filters selected. The authors have developed several computer codes to assist in the diagnostic design process and data deconvolution. Examples of the diagnostic design process and data analysis for a typical pulsed power experiment are presented.

  4. Microgap x-ray detector

    DOE Patents [OSTI]

    Wuest, C.R.; Bionta, R.M.; Ables, E.

    1994-05-03T23:59:59.000Z

    An x-ray detector is disclosed which provides for the conversion of x-ray photons into photoelectrons and subsequent amplification of these photoelectrons through the generation of electron avalanches in a thin gas-filled region subject to a high electric potential. The detector comprises a cathode (photocathode) and an anode separated by the thin, gas-filled region. The cathode may comprise a substrate, such a beryllium, coated with a layer of high atomic number material, such as gold, while the anode can be a single conducting plane of material, such as gold, or a plane of resistive material, such as chromium/silicon monoxide, or multiple areas of conductive or resistive material, mounted on a substrate composed of glass, plastic or ceramic. The charge collected from each electron avalanche by the anode is passed through processing electronics to a point of use, such as an oscilloscope. 3 figures.

  5. Microgap x-ray detector

    DOE Patents [OSTI]

    Wuest, Craig R. (Danville, CA); Bionta, Richard M. (Livermore, CA); Ables, Elden (Livermore, CA)

    1994-01-01T23:59:59.000Z

    An x-ray detector which provides for the conversion of x-ray photons into photoelectrons and subsequent amplification of these photoelectrons through the generation of electron avalanches in a thin gas-filled region subject to a high electric potential. The detector comprises a cathode (photocathode) and an anode separated by the thin, gas-filled region. The cathode may comprise a substrate, such a beryllium, coated with a layer of high atomic number material, such as gold, while the anode can be a single conducting plane of material, such as gold, or a plane of resistive material, such as chromium/silicon monoxide, or multiple areas of conductive or resistive material, mounted on a substrate composed of glass, plastic or ceramic. The charge collected from each electron avalanche by the anode is passed through processing electronics to a point of use, such as an oscilloscope.

  6. Phase-sensitive X-ray imager

    DOE Patents [OSTI]

    Baker, Kevin Louis

    2013-01-08T23:59:59.000Z

    X-ray phase sensitive wave-front sensor techniques are detailed that are capable of measuring the entire two-dimensional x-ray electric field, both the amplitude and phase, with a single measurement. These Hartmann sensing and 2-D Shear interferometry wave-front sensors do not require a temporally coherent source and are therefore compatible with x-ray tubes and also with laser-produced or x-pinch x-ray sources.

  7. Infrared Spectroscopic, X-ray and Nanoscale Characterization of Strontium Titanate Thin Films

    SciTech Connect (OSTI)

    Webb, J. D.; Moutinho, H. R.; Kazmerski, L. L.; Mueller, C. H.; Rivkin, T. V.; Treece, R. E.; Dalberth, M.; Rogers, C. T.

    1997-01-01T23:59:59.000Z

    Attenuated total reflectance (ATR) measurements were performed using Fourier transform infrared (FTIR) spectroscopy in the ATR mode with a thallium iodobromide (KRS-5) crystal to measure the frequencies of the v{sub 3} and v{sub 4} phonon absorption bands in thin strontium titanate films deposited on single-crystal yttrium-barium copper oxide (YBCO), lanthanum aluminate, magnesium oxide, and strontium titanate substrates. The KRS-5 crystal enabled FTIR-ATR measurements to be made at frequencies above 400 cm-1. Atomic force microscopy (AFM) and X-ray diffraction (XRD) measurements were also made to further characterize the films. The measurements were repeated on single-crystal specimens of strontium titanate and the substrates for comparison. Softening in the frequency of the v{sub 4} transverse optical phonon in the lattice-mismatched films below the established value of 544 cm-1 is indicative of the highly textured, polycrystalline ceramic nature of the films and is consistent with the XRD and AFM results.

  8. Filtered x-ray diode diagnostics fielded on the Z-accelerator for source power measurements

    SciTech Connect (OSTI)

    Chandler, G.A.; Deeney, C.; Cuneo, M. [and others

    1998-06-02T23:59:59.000Z

    Filtered x-ray diode, (XRD), detectors are used as primary radiation flux diagnostics on Sandia`s Z-accelerator, which generates nominally a 200 TW, 2 MJ, x-ray pulse. Given such flux levels and XRD sensitivities the detectors are being fielded 23 meters from the source. The standard diagnostic setup and sensitivities are discussed. Vitreous carbon photocathodes are being used to reduce the effect of hydrocarbon contamination present in the Z-machine vacuum system. Nevertheless pre- and post-calibration data taken indicate spectrally dependent changes in the sensitivity of these detectors by up to factors up to 2 or 3.

  9. Mapping Local Strain in Thin Film/Substrate Systems using X-ray

    SciTech Connect (OSTI)

    Yan,H.; Murray, C.; Noyan, I.

    2007-01-01T23:59:59.000Z

    The authors report experimental data and modeling results for reflection microbeam x-ray topographs from a Si substrate strained by an overlying pseudomorphic SiGe film edge. The diffracted x-ray intensity from the Si substrate is strongly asymmetric as a function of distance from the film edge. A model of the diffracted intensity based on the classical Ewald-von Laue dynamical diffraction theory for an antisymmetric strain distribution indicates that the asymmetry in the diffracted beam profile is only due to the scattering process; individual intensity maxima in the intensity profile cannot be uniquely ascribed to individual features in the local strain distribution.

  10. X-ray spectroscopy of low-mass X-ray binaries

    E-Print Network [OSTI]

    Juett, Adrienne Marie, 1976-

    2004-01-01T23:59:59.000Z

    I present high-resolution X-ray grating spectroscopy of neutron stars in low-mass X-ray binaries (LMXBs) using instruments onboard the Chandra X-ray Observatory and the X-ray Multi-Mirror Mission (XMM-Newton). The first ...

  11. Extending The Methodology Of X-ray Crystallography To Allow X-ray

    E-Print Network [OSTI]

    Miao, Jianwei "John"

    , the radiation damage. While the radiation damage problem can be mitigated somewhat by using cryogenic techniques resolution without serious radiation damage to the specimens. Although X-ray crystallography becomesExtending The Methodology Of X-ray Crystallography To Allow X-ray Microscopy Without X-ray Optics

  12. Synchronization of x-ray pulses to the pump laser in an ultrafast x-ray facility

    E-Print Network [OSTI]

    Corlett, J.N.; Barry, W.; Byrd, J.M.; Schoenlein, R.; Zholents, A.

    2002-01-01T23:59:59.000Z

    Accurate timing of ultrafast x-ray probe pulses emitted fromOF X-RAY PULSES TO THE PUMP LASER IN AN ULTRAFAST X-RAY

  13. X-ray holography of biological specimens

    SciTech Connect (OSTI)

    Solem, J.C.

    1984-01-01T23:59:59.000Z

    The author reviews the reasons for x-ray imaging of biological specimens and the techniques presently being used for x-ray microscopy. The author points out the advantages of x-ray holography and the difficulties of obtaining the requisite coherence with conventional sources. The author discusses the problems of radiation damage and the remarkable fact that short pulse x-ray sources circumvent these problems and obtain high-resolution images of specimens in the living state. Finally, the author reviews some of the efforts underway to develop high-intensity coherent x-ray sources for the laboratory. 14 references, 5 figures, 2 tables.

  14. Soft X-ray techniques to study mesoscale magnetism

    E-Print Network [OSTI]

    Kortright, Jeffrey B.

    2003-01-01T23:59:59.000Z

    X-Ray Techniques to Study Mesoscale Magnetism Jeffrey B.X-Ray Techniques to Study Mesoscale Magnetism Jeffrey B.

  15. Techniques for synchronization of X-Ray pulses to the pump laser in an ultrafast X-Ray facility

    E-Print Network [OSTI]

    Corlett, J.N.; Doolittle, L.; Schoenlein, R.; Staples, J.; Wilcox, R.; Zholents, A.

    2003-01-01T23:59:59.000Z

    synchronization of ultrafast x-ray pulses produced in theAccurate timing of ultrafast x-ray probe pulses emitted fromOF X-RAY PULSES TO THE PUMP LASER IN AN ULTRAFAST X-RAY

  16. Controlling X-rays With Light

    SciTech Connect (OSTI)

    Glover, Ernie; Hertlein, Marcus; Southworth, Steve; Allison, Tom; van Tilborg, Jeroen; Kanter, Elliot; Krassig, B.; Varma, H.; Rude, Bruce; Santra, Robin; Belkacem, Ali; Young, Linda

    2010-08-02T23:59:59.000Z

    Ultrafast x-ray science is an exciting frontier that promises the visualization of electronic, atomic and molecular dynamics on atomic time and length scales. A largelyunexplored area of ultrafast x-ray science is the use of light to control how x-rays interact with matter. In order to extend control concepts established for long wavelengthprobes to the x-ray regime, the optical control field must drive a coherent electronic response on a timescale comparable to femtosecond core-hole lifetimes. An intense field is required to achieve this rapid response. Here an intense optical control pulse isobserved to efficiently modulate photoelectric absorption for x-rays and to create an ultrafast transparency window. We demonstrate an application of x-ray transparencyrelevant to ultrafast x-ray sources: an all-photonic temporal cross-correlation measurement of a femtosecond x-ray pulse. The ability to control x-ray/matterinteractions with light will create new opportunities at current and next-generation x-ray light sources.

  17. X-ray Observations of Mrk 231

    E-Print Network [OSTI]

    T. J. Turner

    1998-08-10T23:59:59.000Z

    This paper presents new X-ray observations of Mrk 231, an active galaxy of particular interest due to its large infrared luminosity and the presence of several blueshifted broad absorption line (BAL) systems, a phenomenon observed in a small fraction of QSOs. A ROSAT HRI image of Mrk 231 is presented, this shows an extended region of soft X-ray emission, covering several tens of kpc, consistent with the extent of the host galaxy. An ASCA observation of Mrk 231 is also presented. Hard X-rays are detected but the data show no significant variability in X-ray flux. The hard X-ray continuum is heavily attenuated and X-ray column estimates range from ~ 2 x 10^{22} - 10^{23} cm^{-2} depending on whether the material is assumed to be neutral or ionized, and on the model assumed for the extended X-ray component. These ASCA data provide only the second hard X-ray spectrum of a BAL AGN presented to date. The broad-band spectral-energy-distribution of the source is discussed. While Mrk 231 is X-ray weak compared to Seyfert 1 galaxies, it has an optical-to-X-ray spectrum typical of a QSO.

  18. Dislocation structure and crystallite size-distribution in hexagonal nanomaterials from X-ray peak profile analysis

    E-Print Network [OSTI]

    Gubicza, Jenõ

    profile analysis Tamás Ungár1 and Jen Gubicza1,2 1 Department of General Physics, Eötvös University crystal structure are studied by X-ray diffraction peak profile analysis. The crystallite size, X-ray peak profile analysis, hexagonal crystals, nanostructure. Short title: T. Ungár & J. Gubicza

  19. X-ray transmissive debris shield

    DOE Patents [OSTI]

    Spielman, Rick B. (Albuquerque, NM)

    1994-01-01T23:59:59.000Z

    A composite window structure is described for transmitting x-ray radiation and for shielding radiation generated debris. In particular, separate layers of different x-ray transmissive materials are laminated together to form a high strength, x-ray transmissive debris shield which is particularly suited for use in high energy fluences. In one embodiment, the composite window comprises alternating layers of beryllium and a thermoset polymer.

  20. High speed x-ray beam chopper

    DOE Patents [OSTI]

    McPherson, Armon (Oswego, IL); Mills, Dennis M. (Naperville, IL)

    2002-01-01T23:59:59.000Z

    A fast, economical, and compact x-ray beam chopper with a small mass and a small moment of inertia whose rotation can be synchronized and phase locked to an electronic signal from an x-ray source and be monitored by a light beam is disclosed. X-ray bursts shorter than 2.5 microseconds have been produced with a jitter time of less than 3 ns.

  1. Entangled valence electron-hole dynamics revealed by stimulated attosecond x-ray Raman scattering

    SciTech Connect (OSTI)

    Healion, Daniel; Zhang, Yu; Biggs, Jason D.; Govind, Niranjan; Mukamel, Shaul

    2012-09-06T23:59:59.000Z

    We show that broadband x-ray pulses can create wavepackets of valence electrons and holes localized in the vicinity of a selected atom (nitrogen, oxygen or sulfur in cysteine) by resonant stimulated Raman scattering. The subsequent dynamics reveals highly correlated motions of entangled electrons and hole quasiparticles. This information goes beyond the time-dependent total charge density derived from x-ray diffraction.

  2. X-ray populations in galaxies

    E-Print Network [OSTI]

    G. Fabbiano

    2005-11-09T23:59:59.000Z

    Today's sensistive, high resolution Chandra X-ray observations allow the study of many populations of X-ray sources. The traditional astronomical tools of photometric diagrams and luminosity functions are now applied to these populations, and provide the means for classifying the X-ray sources and probing their evolution. While overall stellar mass drives the amount of X-ray binaries in old stellar population, the amount of sources in star-forming galaxies is related to the star formation rate. Shart-lived, luminous, high mass binaries (HNXBs) dominate these young populations.

  3. X-ray laser microscope apparatus

    DOE Patents [OSTI]

    Suckewer, Szymon (Princeton, NJ); DiCicco, Darrell S. (Plainsboro, NJ); Hirschberg, Joseph G. (Coral Gables, FL); Meixler, Lewis D. (East Windsor, NJ); Sathre, Robert (Princeton, NJ); Skinner, Charles H. (Lawrenceville, NJ)

    1990-01-01T23:59:59.000Z

    A microscope consisting of an x-ray contact microscope and an optical microscope. The optical, phase contrast, microscope is used to align a target with respect to a source of soft x-rays. The source of soft x-rays preferably comprises an x-ray laser but could comprise a synchrotron or other pulse source of x-rays. Transparent resist material is used to support the target. The optical microscope is located on the opposite side of the transparent resist material from the target and is employed to align the target with respect to the anticipated soft x-ray laser beam. After alignment with the use of the optical microscope, the target is exposed to the soft x-ray laser beam. The x-ray sensitive transparent resist material whose chemical bonds are altered by the x-ray beam passing through the target mater GOVERNMENT LICENSE RIGHTS This invention was made with government support under Contract No. De-FG02-86ER13609 awarded by the Department of Energy. The Government has certain rights in this invention.

  4. Flat-response x-ray-diode-detector development

    SciTech Connect (OSTI)

    Tirsell, G.

    1982-10-01T23:59:59.000Z

    In this report we discuss the design of an improved sub-nanosecond flat response x-ray diode detector needed for ICF diagnostics. This device consists of a high Z cathode and a complex filter tailored to flatten the response so that the total x-ray energy below 1.5 keV can be measured using a single detector. Three major problems have become evident as a result of our work with the original LLNL design including deviation from flatness due to a peak in the response below 200 eV, saturation at relatively low x-ray fluences, and long term gold cathode instability. We are investigating grazing incidence reflection to reduce the response below 200 eV, new high Z cathode materials for long term stability, and a new complex filter for improved flatness. Better saturation performance will require a modified XRD detector under development with reduced anode to cathode spacing and increased anode bias voltage.

  5. X-ray spectroscopy of neutron star low-mass X-ray binaries

    E-Print Network [OSTI]

    Krauss, Miriam Ilana

    2007-01-01T23:59:59.000Z

    In this thesis, I present work spanning a variety of topics relating to neutron star lowmass X-ray binaries (LMXBs) and utilize spectral information from X-ray observations to further our understanding of these sources. ...

  6. Phased Contrast X-Ray Imaging

    ScienceCinema (OSTI)

    Erin Miller

    2012-12-31T23:59:59.000Z

    The Pacific Northwest National Laboratory is developing a range of technologies to broaden the field of explosives detection. Phased contrast X-ray imaging, which uses silicon gratings to detect distortions in the X-ray wave front, may be applicable to mail or luggage scanning for explosives; it can also be used in detecting other contraband, small-parts inspection, or materials characterization.

  7. X-ray source populations in galaxies

    E-Print Network [OSTI]

    G. Fabbiano

    2005-11-16T23:59:59.000Z

    Today's sensitive, high-resolution X-ray observations allow the study of populations of X-ray sources, in the luminosity range of Galactic X-ray binaries, in galaxies as distant as 20-30 Mpc. The traditional astronomical tools of photometric diagrams and luminosity functions are now applied to these populations, providing a direct probe of the evolved binary component of different stellar populations. The study of the X-ray populations of E and S0 galaxies has revamped the debate on the formation and evolution of low-mass X-ray binaries (LMXBs) and on the role of globular clusters in these processes. While overall stellar mass drives the amount of X-ray binaries in old stellar populations, the amount of sources in star forming galaxies is related to the star formation rate. Short-lived, luminous, high-mass binaries (HMXBs) dominate these young populations. The most luminous sources in these systems are the debated ULXs, which have been suggested to be ~100-1000 Msol black holes, but could alternatively include a number of binaries with stellar mass black holes. Very soft sources have also been discovered in many galaxies and their nature is currently being debated. Observations of the deep X-ray sky, and comparison with deep optical surveys, are providing the first evidence of the X-ray evolution of galaxies.

  8. BaZn{sub 2}Si{sub 2}O{sub 7} and the solid solution series BaZn{sub 2?x}Co{sub x}Si{sub 2}O{sub 7} (0X-ray diffraction and dilatometry

    SciTech Connect (OSTI)

    Kerstan, Marita; Thieme, Christian; Grosch, Matthias; Müller, Matthias; Rüssel, Christian, E-mail: ccr@rz.uni-jena.de

    2013-11-15T23:59:59.000Z

    For sealing of solid oxide fuel cells, glasses from which crystalline phases with high coefficient of thermal expansion (CTE) can be crystallized are required. In this paper, a new solid solution series BaZn{sub 2?x}Co{sub x}Si{sub 2}O{sub 7} (0X-ray diffraction and high-temperature X-ray diffraction (BaZn{sub 2}Si{sub 2}O{sub 7}). Sintered specimens were characterized by dilatometry. The introduction of Co{sup 2+} does not lead to a change in the space group. All compounds show a transition of a low to a high temperature modification. The attributed temperature increases from 300 °C for BaZn{sub 2}Si{sub 2}O{sub 7} to 850 °C for BaCo{sub 2}Si{sub 2}O{sub 7}. The volume expansion which runs parallel to the phase transition decreases with increasing cobalt concentration. The phase BaZn{sub 2}Si{sub 2}O{sub 7} shows the largest CTE and a steep volume effect during phase transition. For the compound BaZn{sub 0.25}Co{sub 1.75}Si{sub 2}O{sub 7} the CTE is minimum (8.6×10{sup ?6} K{sup ?1} (50–900 °C)) and increases again until for the compound BaCo{sub 2}Si{sub 2}O{sub 7} a CTE of 16.6×10{sup ?6} K{sup ?1} (50–900 °C) is reached. In the cobalt rich composition range, the CTEs are in the right range for high temperature fuel cells and can be adjusted by the composition. - Graphical abstract: The composition of the solid solution BaZn{sub 2?x}Co{sub x}Si{sub 2}O{sub 7} strongly affects the thermal expansion. Display Omitted - Highlights: • We examined the thermal expansion of solid solutions BaZn{sub 2?x}Co{sub x}Si{sub 2}O{sub 7} (0

  9. Lattice Expansion of LSCF-6428 Cathodes Measured by In-situ XRD during SOFC Operation

    SciTech Connect (OSTI)

    Hardy, John S.; Templeton, Jared W.; Edwards, Danny J.; Lu, Zigui; Stevenson, Jeffry W.

    2012-01-03T23:59:59.000Z

    A new capability has been developed for analyzing solid oxide fuel cells (SOFCs). This paper describes the initial results of in-situ x-ray diffraction (XRD) of the cathode on an operating anode-supported solid oxide fuel cell. It has been demonstrated that XRD measurements of the cathode can be performed simultaneously with electrochemical measurements of cell performance or electrochemical impedance spectroscopy (EIS). While improvements to the technique are still to be made, the XRD pattern of a lanthanum strontium cobalt ferrite (LSCF) cathode with the composition La0.6Sr0.4Co0.2Fe0.8O3-? (LSCF-6428) was found to continually but gradually change over the course of more than 60 hours of operation in air under typical SOFC operating conditions. It was determined that the most significant change was a gradual increase in the cubic lattice parameters of the LSCF from 3.92502 Å (as determined from the integration of the first 20 hours of XRD patterns) to 3.92650 Å (from the integration of the last 20 hours). This analysis also revealed that there were several peaks from unidentified minor phases that increased in intensity over this timeframe. After a temporary loss of airflow early in the test, the cell generated between 225 and 250 mW/cm2 for the remainder of the test. A large low frequency arc in the impedance spectra suggests the cell performance was gas diffusion limited and that there is room for improvement in air delivery to the cell.

  10. Theoretical standards in x-ray spectroscopies. Annual progress report, 1991--1992

    SciTech Connect (OSTI)

    Not Available

    1992-09-01T23:59:59.000Z

    We propose to extend our state-of-the-art, ab initio XAFS (X-ray absorption fine structure) codes, FEFF. Our current work has been highly successful in achieving accurate, user-friendly XAFS standards, exceeding the performance of both tabulated standards and other codes by a considerable margin. We now propose to add the capability to treat more complex materials. This includes multiple-scattering, polarization dependence, an approximate treatment of XANES (x-ray absorption near edge structure), and other improvements. We also plan to adapt FEFF to other spectroscopies, e.g. photoelectron diffraction (PD) and diffraction anomalous fine structure (DAFS).

  11. Time-domain sampling of x-ray pulses using an ultrafast sample response

    SciTech Connect (OSTI)

    Gaal, P.; Shayduk, R. [Helmholtz-Zentrum Berlin fuer Materialien und Energie GmbH, Wilhelm-Conrad-Roentgen Campus, BESSY II, Albert-Einstein-Str. 15, 12489 Berlin (Germany); Schick, D.; Herzog, M.; Bojahr, A.; Goldshteyn, J.; Navirian, H. A.; Leitenberger, W. [Institut fuer Physik und Astronomie, Universitaet Potsdam, Karl-Liebknecht-Str. 24-25, 14476 Potsdam (Germany); Vrejoiu, I. [Max-Planck-Institut fuer Mikrostrukturphysik, Weinberg 2, 06120 Halle (Germany); Khakhulin, D.; Wulff, M. [European Synchrotron Radiation Facility (ESRF), 6 rue Jules Horowitz, 38000 Grenoble (France); Bargheer, M. [Helmholtz-Zentrum Berlin fuer Materialien und Energie GmbH, Wilhelm-Conrad-Roentgen Campus, BESSY II, Albert-Einstein-Str. 15, 12489 Berlin (Germany); Institut fuer Physik und Astronomie, Universitaet Potsdam, Karl-Liebknecht-Str. 24-25, 14476 Potsdam (Germany)

    2012-12-10T23:59:59.000Z

    We employ the ultrafast response of a 15.4 nm thin SrRuO{sub 3} layer grown epitaxially on a SrTiO{sub 3} substrate to perform time-domain sampling of an x-ray pulse emitted from a synchrotron storage ring. Excitation of the sample with an ultrashort laser pulse triggers coherent expansion and compression waves in the thin layer, which turn the diffraction efficiency on and off at a fixed Bragg angle during 5 ps. This is significantly shorter than the duration of the synchrotron x-ray pulse of 100 ps. Cross-correlation measurements of the ultrafast sample response and the synchrotron x-ray pulse allow to reconstruct the x-ray pulse shape.

  12. Photosynthesis and structure of electroless Ni-P films by synchrotron x-ray irradiation

    SciTech Connect (OSTI)

    Hsu, P.-C.; Wang, C.-H.; Yang, T.-Y.; Hwu, Y.-K.; Lin, C.-S.; Chen, C.-H.; Chang, L.-W.; Seol, S.-K.; Je, J.-H.; Margaritondo, G. [Institute of Physics, Academia Sinica, NanKang, Taipei 115, Taiwan and Department of Materials Science and Engineering, National Taiwan University, Taipei 106, Taiwan (China); Institute of Physics, Academia Sinica, NanKang, Taipei 115, Taiwan (China); Institute of Physics, Academia Sinica, NanKang, Taipei 115, Taiwan (China); Department of Engineering and System Science, National Tsing Hua University, Hsinchu, 300, Taiwan (China) and Institute of Optoelectronic Sciences, National Taiwan Ocean University, Keelung 202, Taiwan (China); Department of Materials Science and Engineering, National Taiwan University, Taipei 106, Taiwan (China); Kinsus Interconnect Technology Co., Taoyuang 327, Taiwan (China); Department of Materials Science and Optoelectronic Engineering, National Sun Yat-Sen University, Kaoshung 804, Taiwan (China); X-ray Imaging Center, Pohang University of Science and Technology, Pohang 790-784 (Korea, Republic of) and Department of Materials Science and Engineering, Pohang University of Science and Technology, Pohang 790-784 (Korea); Ecole Polytechnique Federale de Lausanne (EPFL), CH-1015 Lausanne (Switzerland)

    2007-05-15T23:59:59.000Z

    The authors describe an electroless deposition method for thin films, based on the irradiation by an x-ray beam emitted by a synchrotron source. Specifically, Ni-P films were deposited at room temperature. This synthesis is a unique combination of photochemical and electrochemical processes. The influence of the pH value on the formation and structural properties of the films was examined by various characterization tools including scanning electron microscopy, x-ray diffraction, and x-ray absorption spectroscopy. Real time monitoring of the deposition process by coherent x-ray microscopy reveals that the formation of hydrogen bubbles leads to a self-catalysis effect without a preexisting catalyst. The mechanisms underlying the deposition process are discussed in details.

  13. THz Pump and X-Ray Probe Development at LCLS

    SciTech Connect (OSTI)

    Fisher, Alan S; /SLAC, LCLS; Durr, Hermann; /SIMES, Stanford /SLAC, PULSE; Lindenberg, Aaron; Stanford U., Materials Sci.Dept.; /SIMES, Stanford /SLAC, PULSE; Reis, David; /SIMES, Stanford /SLAC, PULSE /Stanford U., Dept. Appl. Phys.; Frisch, Josef; Loos, Henrik; Petree, Mark; /SLAC, LCLS; Daranciang, Dan; /Stanford U., Chem. Dept.; Fuchs, Matthias; /SLAC, PULSE; Ghimire, Shambhu; /SLAC, PULSE; Goodfellow, John; /Stanford U., Materials Sci. Dept.

    2011-11-08T23:59:59.000Z

    We report on measurements of broadband, intense, coherent transition radiation at terahertz frequencies, generated as the highly compressed electron bunches in Linear Coherent Light Source (LCLS) pass through a thin metal foil. The foil is inserted at 45{sup o} to the electron beam, 31 m downstream of the undulator. The THz emission passes downward through a diamond window to an optical table below the beamline. A fully compressed 350-pC bunch produces up to 0.5 mJ in a nearly half-cycle pulse of 50 fs FWHM with a spectrum peaking at 10 THz. We estimate a peak field at the focus of over 2.5 GV/m. A 20-fs Ti:sapphire laser oscillator has recently been installed for electro-optic measurements. We are developing plans to add an x-ray probe to this THz pump, by diffracting FEL x rays onto the table with a thin silicon crystal. The x rays would arrive with an adjustable time delay after the THz. This will provide a rapid start to user studies of materials excited by intense single-cycle pulses and will serve as a step toward a THz transport line for LCLS-II.

  14. X-Ray Nanoimaging: Instruments and Methods

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of ScienceandMesa del SolStrengtheningWildfires may contribute more toConsensusX-RayX-Ray ImagingX-Ray

  15. Sensing the wavefront of x-ray free-electron lasers using aerosol spheres

    SciTech Connect (OSTI)

    Loh, N.Duane; Starodub, Dimitri; Lomb, Lukas; Hampton, Christina Y.; Martin, Andrew V.; Sierra, Raymond G.; Barty, Anton; Aquila, Andrew; Schulz, Joachim; Steinbrener, Jan; Shoeman, Robert L.; Kassemeyer, Stephan; Bostedt, Christoph; Bozek, John; Epp, Sascha W.; Erk, Benjamin; Hartmann, Robert; Rolles, Daniel; Rudenko, Artem; Rudek, Benedikt; Foucar, Lutz

    2014-04-22T23:59:59.000Z

    Characterizing intense, focused x-ray free electron laser (FEL) pulses is crucial for their use in diffractive imaging. We describe how the distribution of average phase tilts and intensities on hard x-ray pulses with peak intensities of 10 21 W/m2 can be retrieved from an ensemble of diffraction patterns produced by 70 nm-radius polystyrene spheres, in a manner that mimics wave-front sensors. Besides showing that an adaptive geometric correction may be necessary for diffraction data from randomly injected sample sources, the paper demonstrates the possibility of collecting statistics on structured pulses using only the diffraction patterns they generate and highlights the imperative to study its impact on single-particle diffractive imaging.

  16. Hard X-ray Fluorescence Measurements of Heteroepitaxial Solid...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Hard X-ray Fluorescence Measurements of Heteroepitaxial Solid Oxide Fuel Cell Cathode Materials. Hard X-ray Fluorescence Measurements of Heteroepitaxial Solid Oxide Fuel Cell...

  17. Using X-Ray Computed Tomography in Pore Structure Characterization...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Using X-Ray Computed Tomography in Pore Structure Characterization for a Berea Sandstone: Resolution Effect. Using X-Ray Computed Tomography in Pore Structure Characterization for...

  18. Manipulating X-rays with Tiny Mirrors | Argonne National Laboratory

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    for controlling X-rays. MEMS, or microelectromechanical systems, allow shrinking the optics to the microscale creating ultrafast devices for reflecting X-rays at precise times...

  19. Fuel Injection and Spray Research Using X-Ray Diagnostics

    Broader source: Energy.gov (indexed) [DOE]

    temperature ambient (plastic windows) 5 Radiography - Monochromatic x-rays - Absorption of x-rays by the fuel - Ensemble averaged (flux limited) - Room temperature ambient...

  20. Fuel Injection and Spray Research Using X-Ray Diagnostics

    Broader source: Energy.gov (indexed) [DOE]

    by ECN using several different techniques - Silicone molds (Valencia) - X-ray absorption tomography (CAT) - X-Ray phase contrast imaging (Argonne) - Microscopy (Sandia) ...

  1. X-ray induced optical reflectivity

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Durbin, Stephen M.

    2012-01-01T23:59:59.000Z

    The change in optical reflectivity induced by intense x-ray pulses can now be used to study ultrafast many body responses in solids in the femtosecond time domain. X-ray absorption creates photoelectrons and core level holes subsequently filled by Auger or fluorescence processes, and these excitations ultimately add conduction and valence band carriers that perturb optical reflectivity.Optical absorption associated with band filling and band gap narrowing is shown to explain the basic features found in recent measurements on an insulator (silicon nitride, Si3N4), a semiconductor(gallium arsenide,GaAs), and a metal (gold,Au), obtained with ?100 fs x-ray pulses at 500-2000 eV and probed with 800 nm laser pulses. In particular GaAs exhibits an abrupt drop in reflectivity, persisting only for a time comparable to the x-ray excitation pulse duration, consistent with prompt band gap narrowing.

  2. Columbia University X-Ray Measurements

    E-Print Network [OSTI]

    Columbia University X-Ray Measurements of the Levitated Dipole Experiment J. L. Ellsworth, J. Kesner MIT Plasma Science and Fusion Center D.T. Garnier, A.K. Hansen, M.E. Mauel Columbia University

  3. Small Angle X-Ray Scattering Detector

    DOE Patents [OSTI]

    Hessler, Jan P.

    2004-06-15T23:59:59.000Z

    A detector for time-resolved small-angle x-ray scattering includes a nearly constant diameter, evacuated linear tube having an end plate detector with a first fluorescent screen and concentric rings of first fiber optic bundles for low angle scattering detection and an annular detector having a second fluorescent screen and second fiber optic bundles concentrically disposed about the tube for higher angle scattering detection. With the scattering source, i.e., the specimen under investigation, located outside of the evacuated tube on the tube's longitudinal axis, scattered x-rays are detected by the fiber optic bundles, to each of which is coupled a respective photodetector, to provide a measurement resolution, i.e., dq/q, where q is the momentum transferred from an incident x-ray to an x-ray scattering specimen, of 2% over two (2) orders of magnitude in reciprocal space, i.e., qmax/qmin approx=lO0.

  4. Lensless X-Ray Imaging in Reflection

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Imaging in Reflection Print Wednesday, 26 October 2011 00:00 The advent of x-ray free-electron laser (XFEL) light sources has led to an outburst of research activities in the field...

  5. X-ray source for mammography

    DOE Patents [OSTI]

    Logan, Clinton M. (Pleasanton, CA)

    1994-01-01T23:59:59.000Z

    An x-ray source utilizing anode material which shifts the output spectrum to higher energy and thereby obtains higher penetrating ability for screening mammography application, than the currently utilized anode material. The currently used anode material (molybdenum) produces an energy x-ray spectrum of 17.5/19.6 keV, which using the anode material of this invention (e.g. silver, rhodium, and tungsten) the x-ray spectrum would be in the 20-35 keV region. Thus, the anode material of this invention provides for imaging of breasts with higher than average x-ray opacity without increase of the radiation dose, and thus reduces the risk of induced breast cancer due to the radiation dose administered for mammograms.

  6. X-ray grid-detector apparatus

    DOE Patents [OSTI]

    Boone, John M. (Folsom, CA); Lane, Stephen M. (Oakland, CA)

    1998-01-27T23:59:59.000Z

    A hybrid grid-detector apparatus for x-ray systems wherein a microchannel plate structure has an air-interspaced grid portion and a phosphor/optical fluid-filled grid portion. The grids are defined by multiple adjacent channels separated by lead-glass septa. X-rays entering the air-interspaced grid portion at an angle of impingement upon the septa are attenuated, while non-impinging x-rays pass through to the phosphor/fluid filled portion. X-ray energy is converted to luminescent energy in the phosphor/fluid filled portion and the resultant beams of light are directed out of the phosphor/optical fluid filled portion to an imaging device.

  7. X-ray source for mammography

    DOE Patents [OSTI]

    Logan, C.M.

    1994-12-20T23:59:59.000Z

    An x-ray source is described utilizing anode material which shifts the output spectrum to higher energy and thereby obtains higher penetrating ability for screening mammography application, than the currently utilized anode material. The currently used anode material (molybdenum) produces an energy x-ray spectrum of 17.5/19.6 keV, which using the anode material of this invention (e.g. silver, rhodium, and tungsten) the x-ray spectrum would be in the 20-35 keV region. Thus, the anode material of this invention provides for imaging of breasts with higher than average x-ray opacity without increase of the radiation dose, and thus reduces the risk of induced breast cancer due to the radiation dose administered for mammograms. 6 figures.

  8. Principles of X-ray Navigation

    SciTech Connect (OSTI)

    Hanson, John Eric; /SLAC

    2006-03-17T23:59:59.000Z

    X-ray navigation is a new concept in satellite navigation in which orientation, position and time are measured by observing stellar emissions in x-ray wavelengths. X-ray navigation offers the opportunity for a single instrument to be used to measure these parameters autonomously. Furthermore, this concept is not limited to missions in close proximity to the earth. X-ray navigation can be used on a variety of missions from satellites in low earth orbit to spacecraft on interplanetary missions. In 1997 the Unconventional Stellar Aspect Experiment (USA) will be launched as part of the Advanced Research and Global Observation Satellite (ARGOS). USA will provide the first platform for real-time experimentation in the field of x-ray navigation and also serves as an excellent case study for the design and manufacturing of space qualified systems in small, autonomous groups. Current techniques for determining the orientation of a satellite rely on observations of the earth, sun and stars in infrared, visible or ultraviolet wavelengths. It is possible to use x-ray imaging devices to provide arcsecond level measurement of attitude based on star patterns in the x-ray sky. This technique is explored with a simple simulation. Collimated x-ray detectors can be used on spinning satellites to provide a cheap and reliable measure of orientation. This is demonstrated using observations of the Crab Pulsar taken by the high Energy Astronomy Observatory (HEAO-1) in 1977. A single instrument concept is shown to be effective, but dependent on an a priori estimate of the guide star intensity and thus susceptible to errors in that estimate. A star scanner based on a differential measurement from two x-ray detectors eliminates the need for an a priori estimate of the guide star intensity. A first order model and a second order model of the two star scanner concepts are considered. Many of the stars that emit in the x-ray regime are also x-ray pulsars with frequency stability approaching a part in 10{sup 9}. By observing these pulsations, a satellite can keep accurate time autonomously. They have demonstrated the acquisition and tracking of the Crab nebula pulsar by simulating the operation of a phase-locked loop.

  9. Compton backscattered collimated x-ray source

    DOE Patents [OSTI]

    Ruth, R.D.; Huang, Z.

    1998-10-20T23:59:59.000Z

    A high-intensity, inexpensive and collimated x-ray source is disclosed for applications such as x-ray lithography is disclosed. An intense pulse from a high power laser, stored in a high-finesse resonator, repetitively collides nearly head-on with and Compton backscatters off a bunched electron beam, having relatively low energy and circulating in a compact storage ring. Both the laser and the electron beams are tightly focused and matched at the interaction region inside the optical resonator. The laser-electron interaction not only gives rise to x-rays at the desired wavelength, but also cools and stabilizes the electrons against intrabeam scattering and Coulomb repulsion with each other in the storage ring. This cooling provides a compact, intense bunch of electrons suitable for many applications. In particular, a sufficient amount of x-rays can be generated by this device to make it an excellent and flexible Compton backscattered x-ray (CBX) source for high throughput x-ray lithography and many other applications. 4 figs.

  10. Compton backscattered collmated X-ray source

    DOE Patents [OSTI]

    Ruth, Ronald D. (Woodside, CA); Huang, Zhirong (Stanford, CA)

    2000-01-01T23:59:59.000Z

    A high-intensity, inexpensive and collimated x-ray source for applications such as x-ray lithography is disclosed. An intense pulse from a high power laser, stored in a high-finesse resonator, repetitively collides nearly head-on with and Compton backscatters off a bunched electron beam, having relatively low energy and circulating in a compact storage ring. Both the laser and the electron beams are tightly focused and matched at the interaction region inside the optical resonator. The laser-electron interaction not only gives rise to x-rays at the desired wavelength, but also cools and stabilizes the electrons against intrabeam scattering and Coulomb repulsion with each other in the storage ring. This cooling provides a compact, intense bunch of electrons suitable for many applications. In particular, a sufficient amount of x-rays can be generated by this device to make it an excellent and flexible Compton backscattered x-ray (CBX) source for high throughput x-ray lithography and many other applications.

  11. Compton backscattered collimated x-ray source

    DOE Patents [OSTI]

    Ruth, Ronald D. (Woodside, CA); Huang, Zhirong (Stanford, CA)

    1998-01-01T23:59:59.000Z

    A high-intensity, inexpensive and collimated x-ray source for applications such as x-ray lithography is disclosed. An intense pulse from a high power laser, stored in a high-finesse resonator, repetitively collides nearly head-on with and Compton backscatters off a bunched electron beam, having relatively low energy and circulating in a compact storage ring. Both the laser and the electron beams are tightly focused and matched at the interaction region inside the optical resonator. The laser-electron interaction not only gives rise to x-rays at the desired wavelength, but also cools and stabilizes the electrons against intrabeam scattering and Coulomb repulsion with each other in the storage ring. This cooling provides a compact, intense bunch of electrons suitable for many applications. In particular, a sufficient amount of x-rays can be generated by this device to make it an excellent and flexible Compton backscattered x-ray (CBX) source for high throughput x-ray lithography and many other applications.

  12. X-ray standing waves and surface EXAFS studies of electrochemical interfaces

    SciTech Connect (OSTI)

    Abruna, H.D.; Bommarito, G.M.; Yee, H.S. [Cornell Univ., Ithaca, NY (United States)

    1995-06-01T23:59:59.000Z

    Because of their penetrative power, X-rays are ideally suited for in-situ studies of interfaces in general and solid/liquid interfaces in particular. The recent advent of powerful X-ray synchrotron sources has made experiments of this type feasible. Synchrotron sources offer a broad spectral range of polarized, highly collimated X-rays with intensities that are 10{sup 3}-10{sup 6} higher than those of conventional sources. Moreover, third-generation synchrotron sources, with their projected increase in brightness on the order of 10{sup 4}, will allow for new types of experiments, including the study of dynamic processes in real time. There are a number of X-ray-based surface-sensitive techniques that can be employed in the study of solid/liquid interfaces, including surface EXAFS, X-ray standing waves (XSW), grazing incidence X-ray diffraction (GIXD), and others. In this Account the authors focus on the use of XSW and surface EXAFS. The authors begin with a brief theoretical description followed by experimental aspects of these techniques. The authors then discuss specific examples with emphasis on the underpotential deposition of copper on platinum in the presence and absence of coadsorbates, the potential dependent distribution of interfacial species, and potential dependent structural changes of a redox-active self-assembling monolayer. 33 refs., 7 figs.

  13. Single mimivirus particles intercepted and imaged with an X-ray laser (CXIDB ID 2)

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Seibert, M. Marvin; Ekeberg, Tomas

    These are the files used to reconstruct the images in the paper "Single Mimivirus particles intercepted and imaged with an X-ray laser". Besides the diffracted intensities, the Hawk configuration files used for the reconstructions are also provided. The files from CXIDB ID 2 are the pattern and configuration files for the pattern showed in Figure 2b in the paper.

  14. Single mimivirus particles intercepted and imaged with an X-ray laser (CXIDB ID 1)

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Seibert, M. Marvin; Ekeberg, Tomas; Maia, Filipe R.N.C.

    These are the files used to reconstruct the images in the paper "Single Mimivirus particles intercepted and imaged with an X-ray laser". Besides the diffracted intensities, the Hawk configuration files used for the reconstructions are also provided. The files from CXIDB ID 1 are the pattern and configuration files for the pattern showed in Figure 2a in the paper.

  15. Differential phase contrast X-ray imaging system and components

    DOE Patents [OSTI]

    Stutman, Daniel; Finkenthal, Michael

    2014-07-01T23:59:59.000Z

    A differential phase contrast X-ray imaging system includes an X-ray illumination system, a beam splitter arranged in an optical path of the X-ray illumination system, and a detection system arranged in an optical path to detect X-rays after passing through the beam splitter.

  16. Reflection soft X-ray microscope and method

    DOE Patents [OSTI]

    Suckewer, S.; Skinner, C.H.; Rosser, R.

    1993-01-05T23:59:59.000Z

    A reflection soft X-ray microscope is provided by generating soft X-ray beams, condensing the X-ray beams to strike a surface of an object at a predetermined angle, and focusing the X-ray beams reflected from the surface onto a detector, for recording an image of the surface or near surface features of the object under observation.

  17. X-RAY POWDER DIFFRACTION IDENTIFICATION OF ILLITIC MATERIALS

    E-Print Network [OSTI]

    unknown authors

    expandability. The new technique broadens the computer simulation method eveloped by R. C. Reynolds and J. Hower

  18. X-ray Powder Diffraction (XPD) Scientific scope

    E-Print Network [OSTI]

    in, for example, hydrogen storage, CO2 sequestration, advanced structural ceramics, catalysis, and materials processing. Such materials of high technological value often are complex, nanostructured handling, user-defined specific devices. The side station will operate at a fixed high energy (60 or 80ke

  19. X-RAY POWDER DIFFRACTION 2 (XPD-2) SCIENTIFIC SCOPE

    E-Print Network [OSTI]

    Ohta, Shigemi

    Abeykoon: beamline scientist ADVISORS Simon Billinge (Columbia University/BNL) John Parise (Stony Brook

  20. X-RAY POWDER DIFFRACTION (XPD-1) SCIENTIFIC SCOPE

    E-Print Network [OSTI]

    Ohta, Shigemi

    are implicated in novel electronic properties from high temperature superconductivity to high performance properties. SCIENTIFIC APPLICATIONS Nuclear Applications: · High throughput, combinatorial approach, unmanned storage, CO2 sequestration, advanced structural ceramics, catalysis, and materials processing. ENDSTATION

  1. Biological Imaging by Soft X-Ray Diffraction Microscopy

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    D. Sayre (Stony Brook University); P. Thibault and V. Elser (Cornell University); T. Beetz and C. Jacobsen (Stony Brook University and Brookhaven National Laboratory); M....

  2. Self-terminating diffraction gates femtosecond X-ray nanocrystallography

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of ScienceandMesa del Sol HomeFacebook TwitterSearch-Comments SignExcitonicsmeasurements

  3. Biological Imaging by Soft X-Ray Diffraction Microscopy

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office511041clothAdvanced Materials Advanced Materials Find Find More LikeAndreasHelp Table ofBiological Imaging

  4. Biological Imaging by Soft X-Ray Diffraction Microscopy

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office511041clothAdvanced Materials Advanced Materials Find Find More LikeAndreasHelp Table ofBiological

  5. Biological Imaging by Soft X-Ray Diffraction Microscopy

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office511041clothAdvanced Materials Advanced Materials Find Find More LikeAndreasHelp Table

  6. Biological Imaging by Soft X-Ray Diffraction Microscopy

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office511041clothAdvanced Materials Advanced Materials Find Find More LikeAndreasHelp TableBiological Imaging by

  7. Biological Imaging by Soft X-Ray Diffraction Microscopy

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office511041clothAdvanced Materials Advanced Materials Find Find More LikeAndreasHelp TableBiological Imaging

  8. Biological Imaging by Soft X-Ray Diffraction Microscopy

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office511041clothAdvanced Materials Advanced Materials Find Find More LikeAndreasHelp TableBiological

  9. Biological Imaging by Soft X-Ray Diffraction Microscopy

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office511041clothAdvanced Materials Advanced Materials Find Find More LikeAndreasHelp TableBiologicalBiological

  10. X-Ray Diffraction Microscopy of Magnetic Structures

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurThe Iron SpinPrincetonUsingWhat isJoin theanniversaryI 1 0 3 P 0 d d X O O

  11. X-Ray Diffraction Microscopy of Magnetic Structures

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurThe Iron SpinPrincetonUsingWhat isJoin theanniversaryI 1 0 3 P 0 d d X O OX-Ray

  12. X-Ray Diffraction Microscopy of Magnetic Structures

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurThe Iron SpinPrincetonUsingWhat isJoin theanniversaryI 1 0 3 P 0 d d X O

  13. Biological Imaging by Soft X-Ray Diffraction Microscopy

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625govInstrumentstdmadapInactiveVisiting the TWP TWPAlumniComplexMaterialProduction PetraBiologicalBiological

  14. Biological Imaging by Soft X-Ray Diffraction Microscopy

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625govInstrumentstdmadapInactiveVisiting the TWP TWPAlumniComplexMaterialProduction

  15. Diffraction-Limited Soft X-Ray Workshop

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville Power AdministrationField Campaign: Potential ApplicationYu,

  16. Nonlinear X-ray Compton Scattering

    E-Print Network [OSTI]

    Fuchs, Matthias; Chen, Jian; Ghimire, Shambhu; Shwartz, Sharon; Kozina, Michael; Jiang, Mason; Henighan, Thomas; Bray, Crystal; Ndabashimiye, Georges; Bucksbaum, P H; Feng, Yiping; Herrmann, Sven; Carini, Gabriella; Pines, Jack; Hart, Philip; Kenney, Christopher; Guillet, Serge; Boutet, Sebastien; Williams, Garth; Messerschmidt, Marc; Seibert, Marvin; Moeller, Stefan; Hastings, Jerome B; Reis, David A

    2015-01-01T23:59:59.000Z

    X-ray scattering is a weak linear probe of matter. It is primarily sensitive to the position of electrons and their momentum distribution. Elastic X-ray scattering forms the basis of atomic structural determination while inelastic Compton scattering is often used as a spectroscopic probe of both single-particle excitations and collective modes. X-ray free-electron lasers (XFELs) are unique tools for studying matter on its natural time and length scales due to their bright and coherent ultrashort pulses. However, in the focus of an XFEL the assumption of a weak linear probe breaks down, and nonlinear light-matter interactions can become ubiquitous. The field can be sufficiently high that even non-resonant multiphoton interactions at hard X-rays wavelengths become relevant. Here we report the observation of one of the most fundamental nonlinear X-ray-matter interactions, the simultaneous Compton scattering of two identical photons producing a single photon at nearly twice the photon energy. We measure scattered...

  17. X-ray lithography using holographic images

    DOE Patents [OSTI]

    Howells, Malcolm S. (Berkeley, CA); Jacobsen, Chris (Sound Beach, NY)

    1997-01-01T23:59:59.000Z

    Methods for forming X-ray images having 0.25 .mu.m minimum line widths on X-ray sensitive material are presented. A holgraphic image of a desired circuit pattern is projected onto a wafer or other image-receiving substrate to allow recording of the desired image in photoresist material. In one embodiment, the method uses on-axis transmission and provides a high flux X-ray source having modest monochromaticity and coherence requirements. A layer of light-sensitive photoresist material on a wafer with a selected surface is provided to receive the image(s). The hologram has variable optical thickness and variable associated optical phase angle and amplitude attenuation for transmission of the X-rays. A second embodiment uses off-axis holography. The wafer receives the holographic image by grazing incidence reflection from a hologram printed on a flat metal or other highly reflecting surface or substrate. In this second embodiment, an X-ray beam with a high degree of monochromaticity and spatial coherence is required.

  18. X-ray lithography using holographic images

    DOE Patents [OSTI]

    Howells, M.S.; Jacobsen, C.

    1997-03-18T23:59:59.000Z

    Methods for forming X-ray images having 0.25 {micro}m minimum line widths on X-ray sensitive material are presented. A holographic image of a desired circuit pattern is projected onto a wafer or other image-receiving substrate to allow recording of the desired image in photoresist material. In one embodiment, the method uses on-axis transmission and provides a high flux X-ray source having modest monochromaticity and coherence requirements. A layer of light-sensitive photoresist material on a wafer with a selected surface is provided to receive the image(s). The hologram has variable optical thickness and variable associated optical phase angle and amplitude attenuation for transmission of the X-rays. A second embodiment uses off-axis holography. The wafer receives the holographic image by grazing incidence reflection from a hologram printed on a flat metal or other highly reflecting surface or substrate. In this second embodiment, an X-ray beam with a high degree of monochromaticity and spatial coherence is required. 15 figs.

  19. Radiographic X-Ray Pulse Jitter

    SciTech Connect (OSTI)

    Mitton, C. V., Good, D. E., Henderson, D. J., Hogge, K. W.

    2011-01-15T23:59:59.000Z

    The Dual Beam Radiographic Facility consists of two identical radiographic sources. Major components of the machines are: Marx generator, water-filled pulse-forming line (PFL), water-filled coaxial transmission line, three-cell inductive voltage adder, and rod-pinch diode. The diode pulse has the following electrical specifications: 2.25-MV, 60-kA, 60-ns. Each source has the following x-ray parameters: 1-mm-diameter spot size, 4-rad at 1 m, 50-ns full width half max. The x-ray pulse is measured with PIN diode detectors. The sources were developed to produce high resolution images on single-shot, high-value experiments. For this application it is desirable to maintain a high level of reproducibility in source output. X-ray pulse jitter is a key metric for analysis of reproducibility. We will give measurements of x-ray jitter for each machine. It is expected that x-ray pulse jitter is predominantly due to PFL switch jitter, and therefore a correlation of the two will be discussed.

  20. Oscillations During Thermonuclear X-ray Bursts

    E-Print Network [OSTI]

    Tod E. Strohmayer

    2001-01-12T23:59:59.000Z

    High amplitude, nearly coherent X-ray brightness oscillations during thermonuclear X-ray bursts were discovered with the Rossi X-ray Timing Explorer (RXTE) in early 1996. Spectral and timing evidence strongly supports the conclusion that these oscillations are caused by rotational modulation of the burst emission and that they reveal the spin frequency of neutron stars in low mass X-ray binaries, a long sought goal of X-ray astronomy. Studies carried out over the past year have led to the discovery of burst oscillations in four new sources, bringing to ten the number with confirmed burst oscillations. I review the status of our knowledge of these oscillations and indicate how they can be used to probe the physics of neutron stars. For a few burst oscillation sources it has been proposed that the strongest and most ubiquitous frequency is actually the first overtone of the spin frequency and hence that two nearly antipodal hot spots are present on the neutron star. This inference has important implications for both the physics of thermonuclear burning as well as the mass - radius relation for neutron stars, so its confirmation is crucial. I discuss recent attempts to confirm this hypothesis for 4U 1636-53, the source for which a signal at the putative fundamental (290 Hz) has been claimed.

  1. X-RAY SPECTROMETRY X-Ray Spectrom. 2007; 36: 336342

    E-Print Network [OSTI]

    Limburg, Karin E.

    , Chicago, IL 60637, USA 3 Cornell High Energy Synchrotron Source and School of Applied and EngineeringX-RAY SPECTROMETRY X-Ray Spectrom. 2007; 36: 336­342 Published online in Wiley InterScience (www to establish a breakthrough in high-resolution, simultaneous area mapping of multiple trace elements

  2. X-Ray Data from the X-Ray Data Booklet Online

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Thompson, Albert C.; Attwood, David T.; Gullikson, Eric M.; Howells, Malcolm R.; Kortright, Jeffrey B.; Robinson, Arthur L.; Underwood, James H.; Kim, Kwang-Je; Kirz, Janos; Lindau, Ingolf; Pianetta, Piero; Winick, Herman; Williams, Gwyn P.; Scofield, James H.

    The original X-Ray Data Booklet, published in 1985, became a classic reference source. The online version has been significantly revised and updated to reflect today's science. Hundreds of pages of authoritative data provide the x-ray properties of elements, information on synchrotron radiation, scattering processes, optics and detectors, and other related calculations, formulas, and data tables.

  3. Transformation of x-ray server from a set of WWW-accessed programs into WWW-based library for remote calls from x-ray data analysis software.

    SciTech Connect (OSTI)

    Stepanov, S.; Biosciences Division

    2007-05-01T23:59:59.000Z

    X-ray Server [x-server.gmca.aps.anl.gov] is a public project providing a collection of online software tools for modeling data in the fields of surface X-ray scattering and grazing-incidence X-ray diffraction from thin solid films and multilayers with account for the effects of crystal lattice strains, magnetization and interface roughness. This paper reports on recent developments that are addressing numerous requests to expand the Server access beyond plain web browser sessions and facilitate batch processing, remote fitting and integration of Server programs into users' data analysis software.

  4. Bomb Detection Using Backscattered X-Rays

    SciTech Connect (OSTI)

    Jacobs, J.; Lockwood, G.; Selph, M; Shope, S.; Wehlburg, J.

    1998-10-01T23:59:59.000Z

    Bomb Detection Using Backscattered X-rays* Currently the most common method to determine the contents of a package suspected of containing an explosive device is to use transmission radiography. This technique requires that an x-ray source and film be placed on opposite sides of the package. This poses a problem if the pachge is placed so that only one side is accessible, such as against a wall. There is also a threat to persomel and property since exTlosive devices may be "booby trapped." We have developed a method to x-ray a paclage using backscattered x-rays. This procedure eliminates the use of film behind the target. All of the detection is done from the same side as the source. When an object is subjected to x-rays, some of them iare scattered back towards the source. The backscattenng of x-rays is propordoml to the atomic number (Z) of the material raised to the 4.1 power. This 24"' dependence allows us to easily distinguish between explosives, wires, timer, batteries, and other bomb components. Using transmission radiography-to image the contents of an unknown package poses some undesirable risks. The object must have an x-ray film placed on the side opposite the x-ray source; this cannot be done without moving the package if it has been placed firmly against a wall or pillar. Therefore it would be extremely usefid to be able to image the contents of a package from only one side, without ever having to disturb the package itself. where E is the energy of the incoming x-ray. The volume of x-rays absorbed is important because it is, of course, directly correlated to the intensity of x-mys that will be scattered. Most of the x-rays that scatter will do so in a genemlly forward direction; however, a small percentage do scatter in a backward direction. Figure 1 shows a diagram of the various fates of x-rays directed into an object. The package that was examined in this ex~enment was an attache case made of pressed fiberboardwith a vinyl covering. It was approxirmtely 36 cm wide by 51 cm long by 13 cm deep. The case was placed on an aluminum sheet under the x-ray source. Because of the laborato~ setup, the attache case was rastered in the y-coordinate direction, while the x-ray source mstered in the x-coordinate direction. However, for field use, the x-ray source would of course raster in both the x- and y-coordinate directions, while the object under interrogation would remain stationary and undisturbed. A mobile system for use by law enforcement agencies or bomb disposal squads needs to be portable and somewhat durable. A 300 kV x-ray source should be sufficient for the task requirements and can be mounted on a mobile system. A robotic carriage could be used to transport the x-ray source and the CCD camera to the proximity of the suspect package. The controlling and data analyzing elements of the system' could then be maintained at a &tie distance from the possible explosive. F@re 8 shows a diagram of a conceptual design of a possible system for this type of use. The use of backscattered x-rays for interrogation of packages that may contain explosive devices has been shown to be feasible inthelaboratory. Usinga 150kVx-ray source anddetectors consisting of plastic scintillating material, all bomb components including the wiring were detectable. However, at this time the process requires more time than is desirable for the situations in which it will most likely be needed. Further development of the technology using CCD cameras, rather than the plastic stint illator detectors, shows promise of leading to a much faster system, as well as one with better resolution. Mounting the x- ray source and the CCD camera on a robotic vehicle while keeping the controlling and analyzing components and the opemting personnel a safe distance away from the suspect package will allow such a package to be examined at low risk to human life.

  5. Frontiers in X-Ray Science

    SciTech Connect (OSTI)

    Linda Young

    2011-02-23T23:59:59.000Z

    The year 2010 marked the fiftieth anniversary of the optical laser and the first anniversary of the world's first hard x-ray free-electron laser, the Linac Coherent Light Source (LCLS) at SLAC. This exciting, new accelerator-based source of x-rays provides peak brilliances roughly a billion times greater than currently available from synchrotron sources such as the Advanced Photon Source at Argonne, and thus explores a qualitatively different parameter space. This talk will describe the first experiments at the LCLS aimed at understanding the nature of high intensity x-ray interactions, related applications in ultrafast imaging on the atomic scale and sketch nascent plans for the extension of both linac and storage-ring based photon sources.

  6. The X-ray/submillimetre link

    E-Print Network [OSTI]

    O. Almaini

    2000-01-07T23:59:59.000Z

    It is widely believed that most of the cosmic X-ray background (XRB) is produced by a vast, hitherto undetected population of obscured AGN. Deep X-ray surveys with Chandra and XMM will soon test this hypothesis. Similarly, recent sub-mm surveys with SCUBA have revealed an analogous population of exceptionally luminous, dust-enshrouded {\\em star-forming} galaxies at high redshift. There is now growing evidence for an intimate link between these obscured populations. There are currently large uncertainties in the models, but several independent arguments lead to the conclusion that a significant fraction of the SCUBA sources ($10-30% $) will contain quasars. Recent observational studies of SCUBA survey sources appear to confirm these predictions, although the relative roles of AGN and star-forming activity in heating the dust are unclear. Forthcoming surveys combining X-ray and sub-mm observations will provide a very powerful tool for disentangling these processes.

  7. X-ray atlas of rheumatic diseases

    SciTech Connect (OSTI)

    Dihlmann, W.

    1986-01-01T23:59:59.000Z

    This atlas comprises instructive X-rays of the various inflammatory rheumatic joint diseases in all stages at the extremities and the spinal column. In addition, the complex pattern of the wide range of arthroses, also known as degenerative rheumatic disease is included. Besides the instructive pointers to X-ray diagnosis, the book is also a guide to differential diagnosis. Hence, this book is actually an X-ray atlas of joint diseases in general. Selected Contents: Introduction: What Does ''Rheumatism'' Actually Mean./Radiographic Methodology in Rheumatic Diseases of the Locomotor System/The Mosaic of Arthritis/Adult Rheumatoid Arthritis/Seronegative Spondylarthritis/Classic Collagen Diseases/Enthesiopathies/Gout-Pseudogout

  8. Combined microstructure x-ray optics

    SciTech Connect (OSTI)

    Barbee, T.W. Jr.

    1989-02-01T23:59:59.000Z

    Multilayers are man-made microstructures which vary in depth and are now of sufficient quality to be used as x-ray, soft x-ray and extreme ultraviolet optics. Gratings are man-made in plane microstructures which have been used as optic elements for most of this century. Joining of these two optical microstructures to form combined microstructure optical microstructures to form combined microstructure optical elements has the potential for greatly enhancing both the throughput and the resolution attainable in these spectral ranges. The characteristics of these new optic elements will be presented and compared to experiment with emphasis on the unique properties of these combined microstructures. These results reported are general in nature and not limited to the soft x-ray or extreme ultraviolet spectral domains and also apply to neutrons. 19 refs., 7 figs., 4 tabs.

  9. X-ray reflectivity and surface roughness

    SciTech Connect (OSTI)

    Ocko, B.M.

    1988-01-01T23:59:59.000Z

    Since the advent of high brightness synchrotron radiation sources there has been a phenomenal growth in the use of x-rays as a probe of surface structure. The technique of x-ray reflectivity is particularly relevant to electrochemists since it is capable of probing the structure normal to an electrode surface in situ. In this paper the theoretical framework for x-ray reflectivity is reviewed and the results from previous non-electrochemistry measurements are summarized. These measurements are from the liquid/air interface (CCl/sub 4/), the metal crystal vacuum interface (Au(100)), and from the liquid/solid interface(liquid crystal/silicon). 34 refs., 5 figs.

  10. Dose, exposure time, and resolution in Serial X-ray Crystallography

    SciTech Connect (OSTI)

    Starodub, D; Rez, P; Hembree, G; Howells, M; Shapiro, D; Chapman, H N; Fromme, P; Schmidt, K; Weierstall, U; Doak, R B; Spence, J C

    2007-03-22T23:59:59.000Z

    Using detailed simulation and analytical models, the exposure time is estimated for serial crystallography, where hydrated laser-aligned proteins are sprayed across a continuous synchrotron beam. The resolution of X-ray diffraction microscopy is limited by the maximum dose that can be delivered prior to sample damage. In the proposed Serial Crystallography method, the damage problem is addressed by distributing the total dose over many identical hydrated macromolecules running continuously in a single-file train across a continuous X-ray beam, and resolution is then limited only by the available fluxes of molecules and X-rays. Orientation of the diffracting molecules is achieved by laser alignment. We evaluate the incident X-ray fluence (energy/area) required to obtain a given resolution from (1) an analytical model, giving the count rate at the maximum scattering angle for a model protein, (2) explicit simulation of diffraction patterns for a GroEL-GroES protein complex, and (3) the frequency cut off of the transfer function following iterative solution of the phase problem, and reconstruction of a density map in the projection approximation. These calculations include counting shot noise and multiple starts of the phasing algorithm. The results indicate the number of proteins needed within the beam at any instant for a given resolution and X-ray flux. We confirm an inverse fourth power dependence of exposure time on resolution, with important implications for all coherent X-ray imaging. We find that multiple single-file protein beams will be needed for sub-nanometer resolution on current third generation synchrotrons, but not on fourth generation designs, where reconstruction of secondary protein structure at a resolution of 7 {angstrom} should be possible with short (below 100 s) exposures.

  11. Radiobiological studies using gamma and x rays.

    SciTech Connect (OSTI)

    Potter, Charles Augustus; Longley, Susan W.; Scott, Bobby R. [Lovelace Respiratory Research Institute, Albuquerque, NM; Lin, Yong [Lovelace Respiratory Research Institute, Albuquerque, NM; Wilder, Julie [Lovelace Respiratory Research Institute, Albuquerque, NM; Hutt, Julie A. [Lovelace Respiratory Research Institute, Albuquerque, NM; Padilla, Mabel T. [Lovelace Respiratory Research Institute, Albuquerque, NM; Gott, Katherine M. [Lovelace Respiratory Research Institute, Albuquerque, NM

    2013-02-01T23:59:59.000Z

    There are approximately 500 self-shielded research irradiators used in various facilities throughout the U.S. These facilities use radioactive sources containing either 137Cs or 60Co for a variety of biological investigations. A report from the National Academy of Sciences[1] described the issues with security of particular radiation sources and the desire for their replacement. The participants in this effort prepared two peer-reviewed publications to document the results of radiobiological studies performed using photons from 320-kV x rays and 137Cs on cell cultures and mice. The effectiveness of X rays was shown to vary with cell type.

  12. Energy resolved X-ray grating interferometry

    SciTech Connect (OSTI)

    Thuering, T.; Stampanoni, M. [Swiss Light Source, Paul Scherrer Institut, Villigen PSI (Switzerland) [Swiss Light Source, Paul Scherrer Institut, Villigen PSI (Switzerland); Institute for Biomedical Engineering, Swiss Federal Institute of Technology, Zurich (Switzerland); Barber, W. C.; Iwanczyk, J. S. [DxRay, Inc., Northridge, California 91324 (United States)] [DxRay, Inc., Northridge, California 91324 (United States); Seo, Y.; Alhassen, F. [UCSF Physics Research Laboratory, Department of Radiology and Biomedical Imaging, University of California, San Francisco, California 94143 (United States)] [UCSF Physics Research Laboratory, Department of Radiology and Biomedical Imaging, University of California, San Francisco, California 94143 (United States)

    2013-05-13T23:59:59.000Z

    Although compatible with polychromatic radiation, the sensitivity in X-ray phase contrast imaging with a grating interferometer is strongly dependent on the X-ray spectrum. We used an energy resolving detector to quantitatively investigate the dependency of the noise from the spectral bandwidth and to consequently optimize the system-by selecting the best energy band matching the experimental conditions-with respect to sensitivity maximization and, eventually, dose. Further, since theoretical calculations of the spectrum are usually limited due to non-ideal conditions, an energy resolving detector accurately quantifies the spectral changes induced by the interferometer including flux reduction and beam hardening.

  13. X-Ray Nanoimaging: Instruments and Methods

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of ScienceandMesa del SolStrengtheningWildfires may contribute more toConsensusX-RayX-Ray

  14. High-energy x-ray diffractometer for nondestructive strain depth profile measurement

    SciTech Connect (OSTI)

    Al-Shorman, M. Y. [Department of Physics, Yarmouk University, 21163 Irbid (Jordan)] [Department of Physics, Yarmouk University, 21163 Irbid (Jordan); Jensen, T. C.; Gray, J. N. [Center for Nondestructive Evaluation, Iowa State University, Ames, Iowa 50011 (United States)] [Center for Nondestructive Evaluation, Iowa State University, Ames, Iowa 50011 (United States)

    2013-12-15T23:59:59.000Z

    We describe a lab-based high-energy x-ray diffraction system and a new approach to nondestructively measuring strain profiles in polycrystalline samples. This technique utilizes the tungsten K{sub ?1} characteristic radiation from a standard industrial x-ray tube. We introduce a simulation model that is used to determine strain values from data collected with this system. Examples of depth profiling are shown for shot peened aluminum and titanium samples. Profiles to 1 mm depth in aluminum and 300 ?m depth in titanium with a depth resolution of 20 ?m are presented.

  15. Hexakis(4-phormylphenoxy)cyclotriphosphazene: X-ray and DFT-calculated structures

    SciTech Connect (OSTI)

    Albayrak, Cigdem, E-mail: calbayrak@sinop.edu.tr; Kosar, Basak [Sinop University, Faculty of Education (Turkey); Odabasoglu, Mustafa [Pamukkale University, Chemical Technology Program (Turkey); Bueyuekguengoer, Orhan [Ondokuz Mayis University, Faculty of Arts and Sciences (Turkey)

    2010-12-15T23:59:59.000Z

    The crystal structure of hexakis(4-phormylphenoxy)cyclotriphosphazene is determined by using X-ray diffraction and then the molecular structure is investigated with density functional theory (DFT). X-Ray study shows that the title compound has C-H-{pi} interaction with phosphazene ring. The molecules in the unit cell are packed with Van der Waals and dipole-dipole interactions and the molecules are packed in zigzag shaped. Optimized molecular geometry is calculated with DFT at B3LYP/6-311G(d,p) level. The results from both experimental and theoretical calculations are compared in this study.

  16. Uranium Speciation As a Function of Depth in Contaminated Hanford Sediments - A Micro-XRF, Micro-XRD, and Micro- And Bulk-XAFS Study

    SciTech Connect (OSTI)

    Singer, David M.; Zachara, John M.; Brown, Gordon E.

    2009-02-01T23:59:59.000Z

    Processing ponds at the Hanford, Washington Area 300 site were used for storing basic sodium aluminate and acidic U(VI)-Cu(II)-containing waste from 1943 to 1975. One result of this use is a groundwater plume containing elevated levels of U and Cu beneath the dry ponds and adjacent to the Columbia River. We have used synchrotron-based micro-X-ray fluorescence (?XRF) imaging, micro-X-ray absorption fine structure (?XANES) spectroscopy, and micro-X-ray diffraction (?XRD) techniques combined with bulk U LIII-edge X-ray absorption fine structure (XAFS) spectroscopy to determine the distribution and speciation of U and Cu through the vadose and groundwater zones beneath North Processing Pond #2 (NPP2). Sediment samples were collected from the vadose zone (8’ and 12’ depths), and a sample from the groundwater zone was collected just below the water table (12’-14’ depth). ?XRF imaging revealed two major U occurrences within the vadose and groundwater zones: (1) low to moderate concentrations of U(VI) associated with mineral surfaces (particularly chlorite), and (2) high concentration U(VI)-containing micron-sized particles associated with surface coatings on grains of muscovite and chlorite. These U(VI) hot spots are frequently spatially correlated with Cu(II) hot spots. In the groundwater zone, these particles were identified as the copper-uranyl-silicate cuprosklodowskite and the cupper-uranyl-phosphate metatorbernite. In contrast, the U-Cu-containing particles are X-ray amorphous in the vadose zone. Fits of U LIII-edge XAFS spectra by linear-combination fitting indicate that U speciation consists of ~ 75% uranyl sorbed to clays and ~25% metatorbernite-like X-ray amorphous U-Cu-phosphates (8’ depth); nearly 100% sorbed uranyl (12’ depth); and ~70% sorbed uranyl and ~30% cuprosklodowskite/metatorbernite (ground water zone). These findings suggest that the dissolution of U(VI)-Cu(II)-bearing solids as well as the desorption of U(VI), mainly from phyllosilicates, are important sources of U(VI) in the Area 300 groundwater plume.

  17. Workshops on Science Enabled by a Coherent, CW, Synchrotron X-ray Source, June 2011

    SciTech Connect (OSTI)

    Brock, Joel

    2012-01-03T23:59:59.000Z

    In June of 2011 we held six two-day workshops called "XDL-2011: Science at the Hard X-ray Diffraction Limit". The six workshops covered (1) Diffraction-based imaging techniques, (2) Biomolecular structure from non-crystalline materials, (3) Ultra-fast science, (4) High-pressure science, (5) Materials research with nano-beams and (6) X-ray photon correlation spectroscopy (XPCS), In each workshop, invited speaker from around the world presented examples of novel experiments that require a CW, diffraction-limited source. During the workshop, each invited speaker provided a one-page description of the experiment and an illustrative graphic. The experiments identified by the workshops demonstrate the broad and deep scientific case for a CW coherent synchrotron x-ray source. The next step is to perform detailed simulations of the best of these ideas to test them quantitatively and to guide detailed x-ray beam-line designs. These designs are the first step toward developing detailed facility designs and cost estimates.

  18. Study of optical Laue diffraction

    SciTech Connect (OSTI)

    Chakravarthy, Giridhar, E-mail: cgiridhar84@gmail.com, E-mail: aloksharan@email.com; Allam, Srinivasa Rao, E-mail: cgiridhar84@gmail.com, E-mail: aloksharan@email.com; Satyanarayana, S. V. M., E-mail: cgiridhar84@gmail.com, E-mail: aloksharan@email.com; Sharan, Alok, E-mail: cgiridhar84@gmail.com, E-mail: aloksharan@email.com [Department of Physics, Pondicherry University, Puducherry-605014 (India)

    2014-10-15T23:59:59.000Z

    We present the study of the optical diffraction pattern of one and two-dimensional gratings with defects, designed using desktop pc and printed on OHP sheet using laser printer. Gratings so prepared, using novel low cost technique provides good visual aid in teaching. Diffraction pattern of the monochromatic light (632.8nm) from the grating so designed is similar to that of x-ray diffraction pattern of crystal lattice with point defects in one and two-dimensions. Here both optical and x-ray diffractions are Fraunhofer. The information about the crystalline lattice structure and the defect size can be known.

  19. Bandpass x-ray diode and x-ray multiplier detector

    DOE Patents [OSTI]

    Wang, C.L.

    1982-09-27T23:59:59.000Z

    An absorption-edge of an x-ray absorption filter and a quantum jump of a photocathode determine the bandpass characteristics of an x-ray diode detector. An anode, which collects the photoelectrons emitted by the photocathode, has enhanced amplification provided by photoelectron-multiplying means which include dynodes or a microchannel-plate electron-multiplier. Suppression of undesired high frequency response for a bandpass x-ray diode is provided by subtracting a signal representative of energies above the passband from a signal representative of the overall response of the bandpass diode.

  20. SLAC All Access: X-ray Microscope

    ScienceCinema (OSTI)

    Nelson, Johanna; Liu, Yijin

    2014-06-13T23:59:59.000Z

    SLAC physicists Johanna Nelson and Yijin Liu give a brief overview of the X-ray microscope at the Stanford Synchrotron Radiation Lightsource (SSRL) that is helping improve rechargeable-battery technology by letting researchers peek into the inner workings of batteries as they operate.

  1. Catalog of supersoft X-ray sources

    E-Print Network [OSTI]

    J. Greiner

    2000-05-11T23:59:59.000Z

    This catalog comprises an up-to-date (December 1999) list of luminous (>10^36 erg/s), binary supersoft X-ray sources. This electronic version (including the accompannying Web-pages) supersedes the printed version of Greiner (1996).

  2. X-ray and synchrotron studies of porous silicon

    SciTech Connect (OSTI)

    Sivkov, V. N., E-mail: svn@dm.komisc.ru [Russian Academy of Sciences, Komi Scientific Center, Ural Branch (Russian Federation); Lomov, A. A. [Russian Academy of Sciences, Physical-Technological Institute (Russian Federation)] [Russian Academy of Sciences, Physical-Technological Institute (Russian Federation); Vasil'ev, A. L. [Russian Academy of Sciences, Shubnikov Institute of Crystallography (Russian Federation)] [Russian Academy of Sciences, Shubnikov Institute of Crystallography (Russian Federation); Nekipelov, S. V. [Komi State Pedagogical Institute (Russian Federation)] [Komi State Pedagogical Institute (Russian Federation); Petrova, O. V. [Russian Academy of Sciences, Komi Scientific Center, Ural Branch (Russian Federation)] [Russian Academy of Sciences, Komi Scientific Center, Ural Branch (Russian Federation)

    2013-08-15T23:59:59.000Z

    The results of comprehensive studies of layers of porous silicon of different conductivity types, grown by anodizing standard Si(111) substrates in an electrolyte based on fluoric acid and ethanol with the addition of 5% of iodine and kept in air for a long time, are discussed. Measurements are performed by scanning electron microscopy, high-resolution X-ray diffraction, and ultrasoft X-ray spectroscopy using synchrotron radiation. The structural parameters of the layers (thickness, strain, and porosity) and atomic and chemical composition of the porous-silicon surface are determined. It is found that an oxide layer 1.5-2.3-nm thick is formed on the surface of the silicon skeleton. The near-edge fine structure of the Si 2p absorption spectrum of this layer corresponds to the fine structure of the 2p spectrum of well coordinated SiO{sub 2}. In this case, the fine structure in the Si 2p-edge absorption region of the silicon skeleton is identical to that of the 2p absorption spectrum of crystalline silicon.

  3. An instrument for 3D x-ray nano-imaging

    SciTech Connect (OSTI)

    Holler, M.; Raabe, J.; Diaz, A.; Guizar-Sicairos, M.; Quitmann, C.; Menzel, A.; Bunk, O. [Paul Scherrer Institut, 5232 Villigen PSI (Switzerland)

    2012-07-15T23:59:59.000Z

    We present an instrument dedicated to 3D scanning x-ray microscopy, allowing a sample to be precisely scanned through a beam while the angle of x-ray incidence can be changed. The position of the sample is controlled with respect to the beam-defining optics by laser interferometry. The instrument achieves a position stability better than 10 nm standard deviation. The instrument performance is assessed using scanning x-ray diffraction microscopy and we demonstrate a resolution of 18 nm in 2D imaging of a lithographic test pattern while the beam was defined by a pinhole of 3 {mu}m in diameter. In 3D on a test object of copper interconnects of a microprocessor, a resolution of 53 nm is achieved.

  4. Rise time measurement for ultrafast X-ray pulses

    DOE Patents [OSTI]

    Celliers, Peter M. (Berkeley, CA); Weber, Franz A. (Oakland, CA); Moon, Stephen J. (Tracy, CA)

    2005-04-05T23:59:59.000Z

    A pump-probe scheme measures the rise time of ultrafast x-ray pulses. Conventional high speed x-ray diagnostics (x-ray streak cameras, PIN diodes, diamond PCD devices) do not provide sufficient time resolution to resolve rise times of x-ray pulses on the order of 50 fs or less as they are being produced by modern fast x-ray sources. Here, we are describing a pump-probe technique that can be employed to measure events where detector resolution is insufficient to resolve the event. The scheme utilizes a diamond plate as an x-ray transducer and a p-polarized probe beam.

  5. Rise Time Measurement for Ultrafast X-Ray Pulses

    DOE Patents [OSTI]

    Celliers, Peter M.; Weber, Franz A.; Moon, Stephen J.

    2005-04-05T23:59:59.000Z

    A pump-probe scheme measures the rise time of ultrafast x-ray pulses. Conventional high speed x-ray diagnostics (x-ray streak cameras, PIN diodes, diamond PCD devices) do not provide sufficient time resolution to resolve rise times of x-ray pulses on the order of 50 fs or less as they are being produced by modern fast x-ray sources. Here, we are describing a pump-probe technique that can be employed to measure events where detector resolution is insufficient to resolve the event. The scheme utilizes a diamond plate as an x-ray transducer and a p-polarized probe beam.

  6. X-ray microscopy using grazing-incidence reflections optics

    SciTech Connect (OSTI)

    Price, R.H.

    1983-06-30T23:59:59.000Z

    The role of Kirkpatrick-Baez microscopes as the workhorse of the x-ray imaging devices is discussed. This role is being extended with the development of a 22X magnification Kirkpatrick-Baez x-ray microscope with multilayer x-ray mirrors. These mirrors can operate at large angles, high x-ray energies, and have a narrow, well defined x-ray energy bandpass. This will make them useful for numerous experiments. However, where a large solid angle is needed, the Woelter microscope will still be necessary and the technology needed to build them will be useful for many other types of x-ray optics.

  7. X-ray microscopy using grazing-incidence reflection optics

    SciTech Connect (OSTI)

    Price, R.H.

    1981-08-06T23:59:59.000Z

    The Kirkpatrick-Baez microscopes are described along with their role as the workhorse of the x-ray imaging devices. This role is being extended with the development of a 22X magnification Kirkpatrick-Baez x-ray microscope with multilayer x-ray mirrors. These mirrors can operate at large angles, high x-ray energies, and have a narrow, well defined x-ray energy bandpass. This will make them useful for numerous experiments. However, where a large solid angle is needed, the Woelter microscope will still be necessary and the technology needed to build them will be useful for many other types of x-ray optics.

  8. Possibility of corrector plate tuning of x-ray focusing

    SciTech Connect (OSTI)

    Talman, Richard

    2009-05-01T23:59:59.000Z

    Schemes for focusing a hard x-ray beam to a small spot are described. The theoretical minimum spot size, assuming perfect mirror shape, is shown to be 4 nm FWHM, independent of x-ray wavelength. This is less than the 10 nm previously said to be the minimum achievable diffraction-limited x-ray spot size. While providing the penetrating power only possible with x rays, this approaches the resolution needed to image individual atoms or atomic layers. However, the perfect mirror assumption is physically unrealistic. This paper discusses the compensation of mirror shape errors by a corrector plate and shows that the tolerances for corrector plate shape are far looser than are tolerances for mirror shape. The full eventual success of achieving theoretical minimum resolution will require mirror shape precision considerably better than has been achieved at this time, though far looser than would be required for simpleminded paraboloidal focusing. Two variants of the scheme, subject to the same mathematical treatment, are described. (i) The ''corrector plate'' name is copied from the similarly functioning element of the same name in a Schmidt camera. The focusing is achieved using glancing, yet coherent, reflection from a high-Z paraboloidal mirror. The strategy is to obtain dominant focusing from reflection and to compensate with weak refractive focusing. The reflective focusing is strong and achromatic but insufficiently accurate. The refractive focusing is weak and chromatic but highly accurate. The corrector plate improves resolution the way eyeglasses help a person to see. It can, for example, be ''fitted'' the same trial-and-error way an optometrist establishes a prescription for glasses. Dimensional tolerances for the compensator are far looser than would be needed for a mirror to achieve the same resolution. Unlike compound refractive lenses, attenuation will be small, at least for wavelengths longer than 1 A, because the compensation layer is thin. (ii) For this variant, the corrector plate is a washer-shaped refractive or Fresnel lens, and the mirror is (theoretically) a perfect cone. All focusing is provided by the lens. Even though the cone provides no focusing, it improves the resolution by increasing the numerical aperture of the device. Compared to a paraboloidal shape, it is assumed that the conical shape can be more accurately fabricated. Of the two variants, only the first variant is, in principle, capable of achieving the theoretical minimum resolution. Configurations are suggested, in both case (i) and case (ii), that use currently possible construction precisions to produce resolutions better than have been achieved to date. However, both results will remain well above the theoretical minimum until fabrication techniques have been developed that provide greater precision than is possible at this time.

  9. Structural studies of SrFeO{sub 3} and SrFe{sub 0.5}Nb{sub 0.5}O{sub 3} by employing XRD and XANES spectroscopic techniques

    SciTech Connect (OSTI)

    Akhtar, M. Javed, E-mail: javeda@pinstech.org.pk; Khan, R. Tahir Ali

    2011-10-15T23:59:59.000Z

    The perovskite based SrFeO{sub 3} and SrFe{sub 0.5}Nb{sub 0.5}O{sub 3} materials have been synthesized by solid state reaction methods. The structural properties are investigated using a combination of X-ray diffraction and X-ray absorption fine structure spectroscopic techniques. From the Rietveld refinement of the X-ray diffraction data it has been observed that SrFeO{sub 3} has a simple cubic perovskite structure, which is consistent with the previous literature results; whereas SrFe{sub 0.5}Nb{sub 0.5}O{sub 3} shows a tetragonal structure within P4mm space group. X-ray absorption results demonstrate that the valence state of Fe in SrFeO{sub 3} is (IV); however, it changes to (III) when 50% Nb{sup 5+} is substituted at the Fe sites. - Highlights: {yields} Structural studies by employing XRD and XANES spectroscopic techniques. {yields} Rietveld refinement confirmed SrFeO{sub 3} has cubic structure, space group Pm-3m. {yields} It is revealed that SrFe{sub 0.5}Nb{sub 0.5}O{sub 3} has tetragonal structure, in P4mm space group. {yields} From XANES results it is observed that Fe has valence state of (IV) in SrFeO{sub 3}. {yields} Doping of 50% Nb{sup 5+} at Fe sites, changes Fe valence to (III) in SrFe{sub 0.5}Nb{sub 0.5}O{sub 3}.

  10. X-RAY POINT-SOURCE POPULATIONS CONSTITUTING THE GALACTIC RIDGE X-RAY EMISSION

    SciTech Connect (OSTI)

    Morihana, Kumiko [Institute of Physical and Chemical Research (RIKEN), 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan)] [Institute of Physical and Chemical Research (RIKEN), 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Tsujimoto, Masahiro; Ebisawa, Ken [Japan Aerospace Exploration Agency, Institute of Space and Astronautical Science, 3-1-1 Yoshino-dai, Chuo-ku, Sagamihara, Kanagawa 252-5210 (Japan)] [Japan Aerospace Exploration Agency, Institute of Space and Astronautical Science, 3-1-1 Yoshino-dai, Chuo-ku, Sagamihara, Kanagawa 252-5210 (Japan); Yoshida, Tessei, E-mail: morihana@crab.riken.jp [National Astronomical Observatory of Japan, 2-21-1, Osawa, Mitaka, Tokyo 181-8588 (Japan)] [National Astronomical Observatory of Japan, 2-21-1, Osawa, Mitaka, Tokyo 181-8588 (Japan)

    2013-03-20T23:59:59.000Z

    Apparently diffuse X-ray emission has been known to exist along the central quarter of the Galactic Plane since the beginning of X-ray astronomy; this is referred to as the Galactic Ridge X-ray emission (GRXE). Recent deep X-ray observations have shown that numerous X-ray point sources account for a large fraction of the GRXE in the hard band (2-8 keV). However, the nature of these sources is poorly understood. Using the deepest X-ray observations made in the Chandra bulge field, we present the result of a coherent photometric and spectroscopic analysis of individual X-ray point sources for the purpose of constraining their nature and deriving their fractional contributions to the hard-band continuum and Fe K line emission of the GRXE. Based on the X-ray color-color diagram, we divided the point sources into three groups: A (hard), B (soft and broad spectrum), and C (soft and peaked spectrum). The group A sources are further decomposed spectrally into thermal and non-thermal sources with different fractions in different flux ranges. From their X-ray properties, we speculate that the group A non-thermal sources are mostly active galactic nuclei and the thermal sources are mostly white dwarf (WD) binaries such as magnetic and non-magnetic cataclysmic variables (CVs), pre-CVs, and symbiotic stars, whereas the group B and C sources are X-ray active stars in flares and quiescence, respectively. In the log N-log S curve of the 2-8 keV band, the group A non-thermal sources are dominant above Almost-Equal-To 10{sup -14} erg cm{sup -2} s{sup -1}, which is gradually taken over by Galactic sources in the fainter flux ranges. The Fe K{alpha} emission is mostly from the group A thermal (WD binaries) and the group B (X-ray active stars) sources.

  11. XRD, Electron Microscopy and Vibrational Spectroscopy Characterization of Simulated SB6 HLW Glasses - 13028

    SciTech Connect (OSTI)

    Stefanovsky, S.V. [SIA Radon, 7th Rostovskii lane 2/14, Moscow 119121 (Russian Federation) [SIA Radon, 7th Rostovskii lane 2/14, Moscow 119121 (Russian Federation); Institute of Physical Chemistry and Electrochemistry RAS, Leninskii av. 31, Moscow 119991 (Russian Federation); Nikonov, B.S.; Omelianenko, B.I. [Institute of Geology of Ore Deposits, Petrography, Mineralogy and Geochemistry RAS, Staromonetniy lane 35, Moscow 100117 (Russian Federation)] [Institute of Geology of Ore Deposits, Petrography, Mineralogy and Geochemistry RAS, Staromonetniy lane 35, Moscow 100117 (Russian Federation); Choi, A.; Marra, J.C. [Savannah River National Laboratory, Building 773A, Aiken 29808 (United States)] [Savannah River National Laboratory, Building 773A, Aiken 29808 (United States)

    2013-07-01T23:59:59.000Z

    Sample glasses have been made using SB6 high level waste (HLW) simulant (high in both Al and Fe) with 12 different frit compositions at a constant waste loading of 36 wt.%. As follows from X-ray diffraction (XRD) and optical and scanning electron microscopy (SEM) data, all the samples are composed of primarily glass and minor concentration of spinel phases which form both isometric grains and fine cubic (?1 ?m) crystals. Infrared spectroscopy (IR) spectra of all the glasses within the range of 400-1600 cm{sup -1} consist of the bands due to stretching and bending modes in silicon-oxygen, boron-oxygen, aluminum-oxygen and iron-oxygen structural groups. Raman spectra showed that for the spectra of all the glasses within the range of 850-1200 cm{sup -1} the best fit is achieved by suggestion of overlapping of three major components with maxima at 911-936 cm{sup -1}, 988-996 cm{sup -1} and 1020-1045 cm{sup -1}. The structural network is primarily composed of metasilicate chains and rings with embedded AlO{sub 4} and FeO{sub 4} tetrahedra. Major BO{sub 4} tetrahedra and BO{sub 3} triangles form complex borate units and are present as separate constituents. (authors)

  12. Fundamental Parameters of Low Mass X-ray Binaries II: X-Ray Persistent Systems

    E-Print Network [OSTI]

    Jorge Casares; Phil Charles

    2005-06-24T23:59:59.000Z

    The determination of fundamental parameters in X-ray luminous (persistent) X-ray binaries has been classically hampered by the large optical luminosity of the accretion disc. New methods, based on irradiation of the donor star and burst oscillations, provide the opportunity to derive dynamical information and mass constraints in many persistent systems for the first time. These techniques are here reviewed and the latest results presented.

  13. Brighter Screens for Nondestructive Digital X-ray Radiography

    SciTech Connect (OSTI)

    Miller, Jr., A. C.; Bell, Z. W.; Carpenter, D. A.

    2003-09-15T23:59:59.000Z

    Fine resolution, bright X-ray screens are needed for digital radiography and material characterization at the Y-12 National Security Complex (Y-12). Current technology is simply not adequate for transferring high-energy X-ray images to visible light for demanding digital applications. Low energy radiography and especially emerging tomographic technologies are severely hampered for Y-12 nondestructive evaluation (NDE) applications by dim screens with poor resolution. Also, the development of more advanced materials characterization techniques, such as electron backscatter diffraction (EBSD), is driven by a design agency desire for tighter specifications and more uniform materials. Brighter screens would allow us to probe materials on a finer scale, leading to a better understanding of material behavior. A number of X-ray screen materials were studied that would be suitable for direct replacement in existing digital imaging systems. Spectroscopic evaluations were first made for a several candidates and indicated that lutetium orthosilicate (LSO) would be a promising candidate for MeV images. A relative comparison of brightness at various energies was then completed which showed that cesium iodide (CsI) could increase brightness by over an order of magnitude. Since image quality is also important for better screens, the resolving capabilities of candidate materials were measured. Resolution measurements were completed at X-ray peak energies up to 420KeV with magnified optical imaging systems, and indicated that LSO and Industrial Quality Incorporated glass (IQI) exhibited higher resolution than the CsI screen. The results give a choice of materials that can be tailored to the particular test under consideration. If high-speed images are necessary and some resolution can be sacrificed, the CsI screen will be a good choice. The screen can be replaced by an IQI or LSO unit if higher resolution is needed later, for instance to focus in on a region of interest. A number of significant findings were obtained from this study. Most important of the findings was that materials are commercially available that are much brighter than screens currently in use. This finding meets the original objective of the project. Two objectives of the study; however, were not met. We hoped to evaluate a 'quantum dot' (nanometer-sized particles of semiconductor material) wavelength conversion screen, but the manufacturer ceased production of the screen shortly before the project was started. The dot screen could be efficient in converting ultraviolet light to visible light which would have proved important for utilizing a Cherenkov screen. Since this was a very new, cutting-edge technology, an alternative supplier was not found during the study. Also, high-energy testing of a Cherenkov light screen was not performed due to difficulties in obtaining appropriate approvals for locating test equipment in the high-energy X-ray vault at Y-12. The test is still important, and is being pursued through follow-on funding sources. Although many film shots will be eliminated by the availability of high quality digital images, the largest potential gains result from the availability of clearer images that show fine detail in the parts under analysis. Digital radiographic data also offers the possibility of easily sharing data with other sites. This could prove invaluable when critical material, placement, assembly, or quality issues are pressing. Also, increased throughput in the NDE facility allows statistically significant numbers of units to be analyzed. Digital technologies may in fact be needed just to meet minimum requirements of future demands. Increased brightness screens allow for such innovations as 3-D tomographic images to be acquired in a reasonable time. Much of the skill required to interpret 'flattened' X-ray images is not needed to maneuver around the reconstructed tomogram. This study showed that several commercially available materials are much brighter than screens currently in use. The study also showed that materials othe

  14. Pair Production from Vacuum at the Focus of an X-Ray Free Electron Laser

    E-Print Network [OSTI]

    A. Ringwald

    2001-03-16T23:59:59.000Z

    There are definite plans for the construction of X-ray free electron lasers (FEL), both at DESY, where the so-called XFEL is part of the design of the electron-positron linear collider TESLA, as well as at SLAC, where the so-called Linac Coherent Light Source (LCLS) has been proposed. Such an X-ray laser would allow for high-field science applications: One could make use of not only the high energy and transverse coherence of the X-ray beam, but also of the possibility of focusing it to a spot with a small radius, hopefully in the range of the laser wavelength. Along this route one obtains very large electric fields, much larger than those obtainable with any optical laser of the same power. In this letter we discuss the possibility of obtaining an electric field so high that electron-positron pairs are spontaneously produced in vacuum (Schwinger pair production). We find that if X-ray optics can be improved to approach the diffraction limit of focusing, and if the power of the planned X-ray FELs can be increased to the terawatt region, then there is ample room for an investigation of the Schwinger pair production mechanism.

  15. Transverse Coherence of the LCLS X-Ray Beam

    SciTech Connect (OSTI)

    Not Available

    2010-12-01T23:59:59.000Z

    Self-amplifying spontaneous radiation free-electron lasers, such as the LCLS or the European X-FEL, rely on the incoherent, spontaneous radiation as the seed for the amplifying process. Though this method overcomes the need for an external seed source one drawback is the incoherence of the effective seed signal. The FEL process allows for a natural growth of the coherence because the radiation phase information is spread out within the bunch due to slippage and diffraction of the radiation field. However, at short wavelengths this spreading is not sufficient to achieve complete coherence. In this presentation we report on the results of numerical simulations of the LCLS X-ray FEL. From the obtained radiation field distribution the coherence properties are extracted to help to characterize the FEL as a light source.

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

    SciTech Connect (OSTI)

    Ando, Masami [Institute of Science and Technology, Tokyo Univ. of Science, Yamasaki 2641, Noda, Chiba 278-8510 (Japan); Photon Factory, IMSS, KEK, Oho 1-1, Tsukuba, Ibaraki 305-0801 (Japan); Dept. of Photo-Science, GUAS, Shonan, Hayama, Kanagawa 240-0193 (Japan); Bando, Hiroko; Ueno, Ei [Dept. of Breast-Thyroid-Endocrine Surgery, Univ. of Tsukuba, Ibaraki 305-8573 (Japan)] (and others)

    2007-01-19T23:59:59.000Z

    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. Soft x-ray capabilities for investigating the strongly correlated...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    X-ray, aiming to understand their sciences for applying a new material. In particular, soft x-ray capabilities have been used to obtain microscopic-level understanding of the...

  18. Dawn of x-ray nonlinear optics | Stanford Synchrotron Radiation...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Dawn of x-ray nonlinear optics Wednesday, July 8, 2015 - 3:00pm SLAC, Redtail Hawk Conference Room 108A Speaker: David Reis, PULSE Program Description X-ray free electron lasers...

  19. ALS X-Rays Shine a New Light on Catalysis

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    times science has used high-brilliance x-rays to look so closely at these reactions. Lead author Dr. David Mueller at the ALS using x-rays to characterize working fuel cells....

  20. A World's Top-10 X-ray Crystal Structure

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    A World's Top-10 X-ray Crystal Structure October 7, 2014 Bookmark and Share Philip Coppens An x-ray crystal structure solved by Philip Coppens has been chosen as one of the world's...

  1. Beyond Chandra - the X-ray Surveyor

    E-Print Network [OSTI]

    Weisskopf, Martin C; Tananbaum, Harvey; Vikhlinin, Alexey

    2015-01-01T23:59:59.000Z

    Over the past 16 years, NASA's Chandra X-ray Observatory has provided an unparalleled means for exploring the universe with its half-arcsecond angular resolution. Chandra studies have deepened our understanding of galaxy clusters, active galactic nuclei, galaxies, supernova remnants, planets, and solar system objects addressing almost all areas of current interest in astronomy and astrophysics. As we look beyond Chandra, it is clear that comparable or even better angular resolution with greatly increased photon throughput is essential to address even more demanding science questions, such as the formation and subsequent growth of black hole seeds at very high redshift; the emergence of the first galaxy groups; and details of feedback over a large range of scales from galaxies to galaxy clusters. Recently, NASA Marshall Space Flight Center, together with the Smithsonian Astrophysical Observatory, has initiated a concept study for such a mission named the X-ray Surveyor. This study starts with a baseline payloa...

  2. X-ray radiography for container inspection

    DOE Patents [OSTI]

    Katz, Jonathan I. (Clayton, MO); Morris, Christopher L. (Los Alamos, NM)

    2011-06-07T23:59:59.000Z

    Arrangements of X-ray inspection systems are described for inspecting high-z materials in voluminous objects such as containers. Inspection methods may involve generating a radiographic image based on detected attenuation corresponding to a pulsed beams of radiation transmitted through a voluminous object. The pulsed beams of radiation are generated by a high-energy source and transmitted substantially downward along an incident angle, of approximately 1.degree. to 30.degree., to a vertical axis extending through the voluminous object. The generated radiographic image may be analyzed to detect on localized high attenuation representative of high-z materials and to discriminate high-z materials from lower and intermediate-z materials on the basis of the high density and greater attenuation of high-z material for higher energy (3-10 MeV) X-rays, and the compact nature of threatening masses of fissionable materials.

  3. X-ray mammography with synchrotron radiation

    SciTech Connect (OSTI)

    Burattini, E. (CNR and INFN-Laboratori Nazionali di Frascati, Frascati, Rome (Italy)); Gambaccini, M.; Marziani, M.; Rimondi, O. (Dipartimento di Fisica dell'Universita and Sezione INFN di Ferrara, Ferrara (Italy)); Indovina, P.L. (Dipartimento di Scienze Fisiche dell'Universita and Sezione INFN di Napoli, Naples (Italy)); Pocek, M.; Simonetti, G. (Istituto di Radiologia, Ospedale Sant'Eugenio, Universita di Tor Vergata, Rome (Italy)); Benassi, M.; Tirelli, C. (Istituto Nazionale del Cancro, Regina Elena, Rome (Italy)); Passariello, R. (Cattedra di Radiologia, Universita dell'Aquila, L'Aquila (Italy))

    1992-01-01T23:59:59.000Z

    For the first time in the literature, radiographs of breast phantoms were obtained using several monochromatic synchrotron radiation x-ray beams of selected energy in the range from 14 to 26 keV. In addition, after optimization of the photon energy as a function of the phantom thickness, several mammographs were obtained on surgically removed human breast specimens containing cancer nodules. Comparison between radiographs using a conventional x-ray unit and those obtained of the same specimens utilizing synchrotron monochromatic beams clearly shows that higher contrast and better resolution can be achieved with synchrotron radiation. These results demonstrate the possibility of obtaining radiographs of excised human breast tissue containing a greater amount of radiological information using synchrotron radiation.

  4. X-rays from Supernova Remnants

    E-Print Network [OSTI]

    B. Aschenbach

    2002-08-28T23:59:59.000Z

    A summary of X-ray observations of supernova remnants is presented including the explosion fragment A of the Vela SNR, Tycho, N132D, RX J0852-4622, the Crab Nebula and the 'bulls eye', and SN 1987A, high-lighting the progress made with Chandra and XMM-Newton and touching upon the questions which arise from these observations and which might inspire future research.

  5. Bright X-ray galaxies in SDSS filaments

    E-Print Network [OSTI]

    Tugay, A V

    2013-01-01T23:59:59.000Z

    Eighteen bright X-ray emitting galaxies were found in nearby filaments within SDSS region. Basic X-ray spectral parameters were estimated for these galaxies using power law model with photoelectric absorption. A close pair of X-ray galaxies was found.

  6. Small Angle X-ray Scattering (SAXS) Laboratory Learning Experiences

    E-Print Network [OSTI]

    Meagher, Mary

    .A. & Svergun D.I. (1987). Structure Analysis by Small-Angle X-Ray and Neutron Scattering. NY: Plenum PressSmall Angle X-ray Scattering (SAXS) Laboratory Learning Experiences o - Use of small angle X-ray scattering instrumentation o - Programs that you will use SAXS (BRUKER AXS) PRIMUS (Konarev, Volkov, Koch

  7. Femtosecond laser-electron x-ray source

    DOE Patents [OSTI]

    Hartemann, Frederic V.; Baldis, Hector A.; Barty, Chris P.; Gibson, David J.; Rupp, Bernhard

    2004-04-20T23:59:59.000Z

    A femtosecond laser-electron X-ray source. A high-brightness relativistic electron injector produces an electron beam pulse train. A system accelerates the electron beam pulse train. The femtosecond laser-electron X-ray source includes a high intra-cavity power, mode-locked laser and an x-ray optics system.

  8. Synthesis and characterization of low-OH?fluor-chlorapatite: A single-crystal XRD and NMR spectroscopic study

    SciTech Connect (OSTI)

    McCubbin, Francis M.; Mason, Harris E.; Park, Hyunsoo; Phillips, Brian L.; Parise, John B.; Nekvasil, Hanna; Lindsley, Donald H. (SBU)

    2008-12-12T23:59:59.000Z

    Los-OH apatite of the compositional range Ca{sub 4.99-5.06}(PO{sub 4}){sub 2.98-3.00}F{sub 0.51-0.48}Cl{sub 0.38-0.36}OH{sub 0.14-0.12} was synthesized and characterized structurally by synchrotron-based single-crystal X-ray diffraction (XRD), and multiple nuclear magnetic resonance (NMR) spectroscopic techniques. the average structure is hexagonal with space group P6{sub 3}/m. The presence of scattering in the single-crystal diffraction data set, which is incommensurate within the average hexagonal structure, suggests the presence of localized short-range monoclinic domains. Complex lineshapes in the {sup 31}P and {sup 19}F MAS NMR spectra are also consistent with the presence of an incommensurate phase. No evidence was detected for splitting of the Ca2 site into two distinct sites (as had been previously reported for hexagonal ternary apatities). Structure refinement and {sup 19}F{l_brace}{sup 35}Cl{r_brace} TRAPDOR NMR experiments verified intercolumnal neighboring of F and Cl atoms (inter-column distance of 2.62 {angstrom}) within this low-OH{sup -} apatite suggesting that long-range neighboring of F and Cl within the apatite anion channels is feasible.

  9. X-Ray Interactions with Matter from the Center for X-Ray Optics (CXRO)

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Henke, B.L.; Gullikson, E.M.; Davis, J.C.

    The primary interactions of low-energy x-rays within condensed matter, viz. photoabsorption and coherent scattering, are described for photon energies outside the absorption threshold regions by using atomic scattering factors. The atomic scattering factors may be accurately determined from the atomic photoabsorption cross sections using modified Kramers-Kronig dispersion relations. From a synthesis of the currently available experimental data and recent theoretical calculations for photoabsorption, the angle-independent, forward-scattering components of the atomic scattering factors have been thus semiempirically determined and tabulated here for 92 elements and for the region 50-30,000 eV. Atomic scattering factors for all angles of coherent scattering and at the higher photon energies are obtained from these tabulated forward-scattering values by adding a simple angle-dependent form-factor correction. The incoherent scattering contributions that become significant for the light elements at the higher photon energies are similarly determined. The basic x-ray interaction relations that are used in applied x-ray physics are presented here in terms of the atomic scattering factors. The bulk optical constants are also related to the atomic scattering factors. These atomic and optical relations are applied to the detailed calculation of the reflectivity characteristics of a series of practical x-ray mirror, multilayer, and crystal monochromators. Comparisons of the results of this semiempirical,"atom-like", description of x-ray interactions for the low-energy region with those of experiment and ab initio theory are presented.

  10. Calibrating X-ray Imaging Devices for Accurate Intensity Measurement

    SciTech Connect (OSTI)

    Haugh, M. J.

    2011-07-28T23:59:59.000Z

    The purpose of the project presented is to develop methods to accurately calibrate X-ray imaging devices. The approach was to develop X-ray source systems suitable for this endeavor and to develop methods to calibrate solid state detectors to measure source intensity. NSTec X-ray sources used for the absolute calibration of cameras are described, as well as the method of calibrating the source by calibrating the detectors. The work resulted in calibration measurements for several types of X-ray cameras. X-ray camera calibration measured efficiency and efficiency variation over the CCD. Camera types calibrated include: CCD, CID, back thinned (back illuminated), front illuminated.

  11. High-temperature X-ray analysis of phase evolution in lithium ion conductor Li{sub 1.5}Al{sub 0.5}Ge{sub 1.5}(PO{sub 4}){sub 3}

    SciTech Connect (OSTI)

    He, Kun, E-mail: cbmahekun@163.com; Wang, Yanhang; Zu, Chengkui, E-mail: zuchengkui@126.com; Liu, Yonghua; Zhao, Huifeng; Chen, Jiang; Han, Bin; Ma, Juanrong

    2013-06-15T23:59:59.000Z

    Series of Li{sub 1.5}Al{sub 0.5}Ge{sub 1.5}(PO{sub 4}){sub 3} glass ceramic samples were prepared in this work through the change of heat treatment temperature from 650 to 1050 °C. The structures of glass ceramic samples were characterized by means of high temperature X-ray diffraction and Field Emission Scanning Electron Microscope. And the lithium ionic conductivity was analyzed through AC impedance spectroscopy. Through heat treatment at 850 °C for 4 h for the base glass sample, we obtained a maximum conductivity of 5.8 × 10{sup ?4} S/cm at room temperature. - Graphical Abstract: High temperature X-ray diffraction (HT-XRD) and Rietveld refinement of Li{sub 1.5}Al{sub 0.5}Ge{sub 1.5}(PO{sub 4}){sub 3} (LAGP) glass-ceramics were recorded to investigate the phase transformation, cell parameters and the mass fraction of each crystal phase, which occur in the glass to glass-ceramics process during different crystallization temperatures. The relationship between the average grain size and conductivity that originate from and relate to the crystallization temperature was analyzed by SEM micrograph and AC impedance spectroscopy. - Highlights: • Li{sub 1.5}Al{sub 0.5}Ge{sub 1.5}(PO{sub 4}){sub 3} glass-ceramics were prepared from as-prepared glass. • The phases decomposition and mass fraction of each phase were analyzed by HT-XRD. • Conductivity is relate to grain size that influenced by crystallization temperature.

  12. Apparatus for monitoring X-ray beam alignment

    DOE Patents [OSTI]

    Steinmeyer, P.A.

    1991-10-08T23:59:59.000Z

    A self-contained, hand-held apparatus is provided for monitoring alignment of an X-ray beam in an instrument employing an X-ray source. The apparatus includes a transducer assembly containing a photoresistor for providing a range of electrical signals responsive to a range of X-ray beam intensities from the X-ray beam being aligned. A circuit, powered by a 7.5 VDC power supply and containing an audio frequency pulse generator whose frequency varies with the resistance of the photoresistor, is provided for generating a range of audible sounds. A portion of the audible range corresponds to low X-ray beam intensity. Another portion of the audible range corresponds to high X-ray beam intensity. The transducer assembly may include an a photoresistor, a thin layer of X-ray fluorescent material, and a filter layer transparent to X-rays but opaque to visible light. X-rays from the beam undergoing alignment penetrate the filter layer and excite the layer of fluorescent material. The light emitted from the fluorescent material alters the resistance of the photoresistor which is in the electrical circuit including the audio pulse generator and a speaker. In employing the apparatus, the X-ray beam is aligned to a complete alignment by adjusting the X-ray beam to produce an audible sound of the maximum frequency. 2 figures.

  13. Coded Aperture Imaging for Fluorescent X-rays-Biomedical Applications

    SciTech Connect (OSTI)

    Haboub, Abdel; MacDowell, Alastair; Marchesini, Stefano; Parkinson, Dilworth

    2013-06-01T23:59:59.000Z

    Employing a coded aperture pattern in front of a charge couple device pixilated detector (CCD) allows for imaging of fluorescent x-rays (6-25KeV) being emitted from samples irradiated with x-rays. Coded apertures encode the angular direction of x-rays and allow for a large Numerical Aperture x- ray imaging system. The algorithm to develop the self-supported coded aperture pattern of the Non Two Holes Touching (NTHT) pattern was developed. The algorithms to reconstruct the x-ray image from the encoded pattern recorded were developed by means of modeling and confirmed by experiments. Samples were irradiated by monochromatic synchrotron x-ray radiation, and fluorescent x-rays from several different test metal samples were imaged through the newly developed coded aperture imaging system. By choice of the exciting energy the different metals were speciated.

  14. HgMn Stars as apparent X-ray emitters

    E-Print Network [OSTI]

    Hubrig, S; Mathys, G

    1998-01-01T23:59:59.000Z

    In the ROSAT all-sky survey 11 HgMn stars were detected as soft X-ray emitters (Berghoefer, Schmitt & Cassinelli 1996). Prior to ROSAT, X-ray observations with the Einstein Observatory had suggested that stars in the spectral range B5-A7 are devoid of X-ray emission. Since there is no X-ray emitting mechanism available for these stars (also not for HgMn stars), the usual argument in the case of an X-ray detected star of this spectral type is the existence of an unseen low-mass companion which is responsible for the X-ray emission. The purpose of the present work is to use all available data for our sample of X-ray detected HgMn stars and conclude on the nature of possible companions.

  15. Imaging single cells in a beam of live cyanobacteria with an X-ray laser

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Schot, Gijs, vander

    This entry contains ten diffraction patterns, and reconstructions images, of individual living Cyanobium gracile cells, imaged using 517 eV X-rays from the LCLS XFEL. The Hawk software package was used for phasing. The Uppsala aerosol injector was used for sample injection, assuring very low noise levels. The cells come from various stages of the cell cycle, and were imaged in random orientations.

  16. Hard x-ray or gamma ray laser by a dense electron beam

    SciTech Connect (OSTI)

    Son, S. [18 Caleb Lane, Princeton, New Jersey 08540 (United States); Joon Moon, Sung [8 Benjamin Rush Ln., Princeton, New Jersey 08540 (United States)

    2012-06-15T23:59:59.000Z

    A dense electron beam propagating through a laser undulator can radiate a coherent x-ray or gamma ray. This lasing scheme is studied with the Landau damping theory. The analysis suggests that, with currently available physical parameters, coherent gamma rays of up to 50 keV can be generated. The electron quantum diffraction suppresses the free electron laser action, which limits the maximum radiation.

  17. Structure and dynamics of cadmium telluride studied by x-ray and inelastic neutron scattering

    SciTech Connect (OSTI)

    Niedziela, Jennifer L [ORNL; Stone, Matthew B [ORNL

    2014-01-01T23:59:59.000Z

    We present a combined study of density functional theory, x-ray diffraction, and inelastic neutron scattering examining the temperature dependent structure and lattice dynamics of commercially available cadmium telluride. A subtle change in the structure is evinced near 80~K, which manifests also in the measured phonon density of states. There is no change to the long-range ordered structure. The implications of the change in relation to structural defects are discussed.

  18. Structure and dynamics of cadmium telluride studied by x-ray and inelastic neutron scattering

    SciTech Connect (OSTI)

    Niedziela, J. L., E-mail: niedzielajl@ornl.gov [Instrument and Source Division, Neutron Sciences Directorate, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Stone, M. B., E-mail: stonemb@ornl.gov [Quantum Condensed Matter Division, Neutron Sciences Directorate, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)

    2014-09-08T23:59:59.000Z

    We present a combined study of density functional theory, x-ray diffraction, and inelastic neutron scattering examining the temperature dependent structure and lattice dynamics of commercially available cadmium telluride. A subtle change in the structure is evinced near 80?K, which manifests also in the measured phonon density of states. There is no change to the long-range ordered structure. The implications of the change in relation to structural defects are discussed.

  19. X-ray emission properties of galaxies in Abell 3128

    E-Print Network [OSTI]

    Russell J. Smith

    2003-07-15T23:59:59.000Z

    We use archival Chandra X-ray Observatory data to investigate X-ray emission from early-type galaxies in the rich z=0.06 cluster Abell 3128. By combining the X-ray count-rates from an input list of optically-selected galaxies, we obtain a statistical detection of X-ray flux, unbiased by X-ray selection limits. Using 87 galaxies with reliable Chandra data, X-ray emission is detected for galaxies down to M_B ~ -19.0, with only an upper limit determined for galaxies at M_B ~ -18.3. The ratio of X-ray to optical luminosities is consistent with recent determinations of the low-mass X-ray binary content of nearby elliptical galaxies. Taken individually, in contrast, we detect significant (3sigma) flux for only six galaxies. Of these, one is a foreground galaxy, while two are optically-faint galaxies with X-ray hardness ratios characteristic of active galactic nuclei. The remaining three detected galaxies are amongst the optically-brightest cluster members, and have softer X-ray spectra. Their X-ray flux is higher than that expected from X-ray binaries, by a factor 2-10; the excess suggests these galaxies have retained their hot gaseous haloes. The source with the highest L_X / L_B ratio is of unusual optical morphology with prominent sharp-edged shells. Notwithstanding these few exceptions, the cluster population overall exhibits X-ray properties consistent with their emission being dominated by X-ray binaries. We conclude that in rich cluster environments, interaction with the ambient intra-cluster medium acts to strip most galaxies of their hot halo gas.

  20. Scanning Transmission X-ray Microscopy: Applications in Atmospheric Aerosol Research

    E-Print Network [OSTI]

    Moffet, Ryan C.

    2011-01-01T23:59:59.000Z

    2-ID-B intermediate-energy scanning X-ray microscope at theW. D. , Morrison, G. R. et al. Scanning transmission X-rayX-ray spectromicroscopy with the scanning transmission X-ray

  1. X-ray generation using carbon nanotubes

    E-Print Network [OSTI]

    Parmee, Richard J.; Collins, Clare M.; Milne, William I.; Cole, Matthew T.

    2015-01-06T23:59:59.000Z

    of these sys- tems are illustrated in Figure 2(b) also outlines the principle mode of operation. Here, sealed in an inexpensive and eas- ily fabricated evacuated glass or ceramic envelope, the elec- trons are liberated from a metallic filament, often made... - ment of CNT-based FE sources is provided in [152]. Here we provide a condensed review of the progress, as it pertains to X-ray sources, since then. CNTs have some of the highest attainable aspect ratios, high thermal conductivity, low chemical...

  2. The BMW X-ray Cluster Survey

    E-Print Network [OSTI]

    Alberto Moretti; Luigi Guzzo; Sergio Campana; Stefano Covino; Davide Lazzati; Marcella Longhetti; Emilio Molinari; Maria Rosa Panzera; Gianpiero Tagliaferri; Ian Dell'Antonio

    2001-03-21T23:59:59.000Z

    We describe the main features of the BMW survey of serendipitous X-ray clusters, based on the still unexploited ROSAT-HRI archival observations. The sky coverage, surface density and first deep optical CCD images of the candidates indicate that this sample can represent an excellent complement to the existing PSPC deep cluster surveys and will provide us with a fully independent probe of the evolution of the cluster abundance, in addition to significantly increasing the number of clusters known at z>0.6.

  3. The BMW X-ray Cluster Survey

    E-Print Network [OSTI]

    Moretti, A; Campana, S; Covino, S; Lazzati, D; Longhetti, M; Molinari, E; Panzera, M R; Tagliaferri, G; Dell'Antonio, I P; Moretti, Alberto; Guzzo, Luigi; Campana, Sergio; Covino, Stefano; Lazzati, Davide; Longhetti, Marcella; Molinari, Emilio; Panzera, Maria Rosa; Tagliaferri, Gianpiero; Antonio, Ian Dell'

    2001-01-01T23:59:59.000Z

    We describe the main features of the BMW survey of serendipitous X-ray clusters, based on the still unexploited ROSAT-HRI archival observations. The sky coverage, surface density and first deep optical CCD images of the candidates indicate that this sample can represent an excellent complement to the existing PSPC deep cluster surveys and will provide us with a fully independent probe of the evolution of the cluster abundance, in addition to significantly increasing the number of clusters known at z>0.6.

  4. Lensless X-Ray Imaging in Reflection

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of Science (SC)Integrated Codes |Is Your HomeLatest News ReleasesDepartmentLendingX-Ray Imaging in

  5. Lensless X-Ray Imaging in Reflection

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of Science (SC)Integrated Codes |Is Your HomeLatest News ReleasesDepartmentLendingX-Ray Imaging

  6. Lensless X-Ray Imaging in Reflection

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of Science (SC)Integrated Codes |Is Your HomeLatest News ReleasesDepartmentLendingX-Ray

  7. Lensless X-Ray Imaging in Reflection

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHigh SchoolIn12electron 9 5 -ofLearningLensless ImagingLensless X-Ray

  8. Small Angle X-ray Scattering

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over Our Instagram Secretary Moniz9Morgan ManagingW.tepidumAngle X-ray Scattering

  9. SMB, X-ray Absorption Spectroscopy

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What's PossibleRadiation Protection245C Unlimited ReleaseWelcome to theAbsorption Spectroscopy X-ray

  10. Spectral softening in the X-RAY afterglow of GRB 130925A as predicted by the dust scattering model

    SciTech Connect (OSTI)

    Zhao, Yi-Nan; Shao, Lang, E-mail: lshao@hebtu.edu.cn [Department of Space Science and Astronomy, Hebei Normal University, Shijiazhuang 050024 (China)

    2014-07-01T23:59:59.000Z

    Gamma-ray bursts (GRBs) usually occur in a dense star-forming region with a massive circumburst medium. The small-angle scattering of intense prompt X-ray emission off the surrounding dust grains will have observable consequences and sometimes can dominate the X-ray afterglow. In most of the previous studies, only the Rayleigh-Gans (RG) approximation is employed for describing the scattering process, which works accurately for the typical size of grains (with radius of a ? 0.1 ?m) in the diffuse interstellar medium. When the size of the grains may significantly increase, as in a more dense region where GRBs would occur, the RG approximation may not be valid enough for modeling detailed observational data. In order to study the temporal and spectral properties of the scattered X-ray emission more accurately with potentially larger dust grains, we provide a practical approach using the series expansions of anomalous diffraction (AD) approximation based on the complicated Mie theory. We apply our calculations to understand the puzzling X-ray afterglow of recently observed GRB 130925A that showed a significant spectral softening. We find that the X-ray scattering scenarios with either AD or RG approximation adopted could well reproduce both the temporal and spectral profile simultaneously. Given the plateau present in the early X-ray light curve, a typical distribution of smaller grains as in the interstellar medium would be suggested for GRB 130925A.

  11. X-ray emission from Saturn

    E-Print Network [OSTI]

    Ness, J U; Wolk, S J; Dennerl, K; Burwitz, V

    2004-01-01T23:59:59.000Z

    We report the first unambiguous detection of X-ray emission originating from Saturn with a Chandra observation, duration 65.5 ksec with ACIS-S3. Beyond the pure detection we analyze the spatial distribution of X-rays on the planetary surface, the light curve, and some spectral properties. The detection is based on 162 cts extracted from the ACIS-S3 chip within the optical disk of Saturn. We found no evidence for smaller or larger angular extent. The expected background level is 56 cts, i.e., the count rate is (1.6 +- 0.2) 10^-3 cts/s. The extracted photons are rather concentrated towards the equator of the apparent disk, while both polar caps have a relative photon deficit. The inclination angle of Saturn during the observation was -27 degrees, so that the northern hemisphere was not visible during the complete observation. In addition, it was occulted by the ring system. We found a small but significant photon excess at one edge of the ring system. The light curve shows a small dip twice at identical phases,...

  12. High-pressure X-ray absorption fine structure in the diamond anvil cell and its applications in geological materials

    E-Print Network [OSTI]

    Duffy, Thomas S.

    nano- polycrystalline diamond instead of single crystal anvils, the influence of diamond diffractionHigh-pressure X-ray absorption fine structure in the diamond anvil cell and its applications fine structure in the diamond anvil cell and its applications in geological materials Xinguo Hong1

  13. The variability properties of X-ray steep and X-ray flat quasars

    E-Print Network [OSTI]

    Fabrizio Fiore; Ari Laor; Martin Elvis; Fabrizio Nicastro; Emanuele Giallongo

    1998-03-20T23:59:59.000Z

    We have studied the variability of 6 low redshift, radio quiet `PG' quasars on three timescales (days, weeks, and months) using the ROSAT HRI. The quasars were chosen to lie at the two extreme ends of the ROSAT PSPC spectral index distribution and hence of the H$\\beta$ FWHM distribution. The observation strategy has been carefully designed to provide even sampling on these three basic timescales and to provide a uniform sampling among the quasars We have found clear evidence that the X-ray steep, narrow H_beta, quasars systematically show larger amplitude variations than the X-ray flat broad H_beta quasars on timescales from 2 days to 20 days. On longer timescales we do not find significant differences between steep and flat quasars, although the statistics are poorer. We suggest that the above correlation between variability properties and spectral steepness can be explained in a scenario in which the X-ray steep, narrow line objects are in a higher L/L_Edd state with respect to the X-ray flat, broad line objects. We evaluated the power spectrum of PG1440+356 (the brigthest quasar in our sample) between 2E-7 and 1E-3 Hz, where it goes into the noise. The power spectrum is roughly consistent with a 1/f law between 1E-3 and 2E-6 Hz. Below this frequency it flattens significantly.

  14. X-ray driven channeling acceleration in crystals and carbon nanotubes

    SciTech Connect (OSTI)

    Shin, Young-Min [Department of Physics, Northern Illinois Center for Accelerator and Detector Development (NICADD), Northern Illinois University, Dekalb, Illinois 60115 (United States) [Department of Physics, Northern Illinois Center for Accelerator and Detector Development (NICADD), Northern Illinois University, Dekalb, Illinois 60115 (United States); Fermi National Accelerator Laboratory, Batavia, Illinois 60510 (United States); Still, Dean A.; Shiltsev, Vladimir [Fermi National Accelerator Laboratory, Batavia, Illinois 60510 (United States)] [Fermi National Accelerator Laboratory, Batavia, Illinois 60510 (United States)

    2013-12-15T23:59:59.000Z

    Acceleration of particles channeling in a crystal by means of diffracted x-rays via Bormann anomalous transmission was conceived for heavy ions and muons by Tajima and Cavenago [Phys. Rev. Lett. 59, 1440 (1987)], which potentially offers an appreciably high field gradient on the order of GV/cm. The theoretical model of the high gradient acceleration has been studied in two kinds of atomic structure, crystals and carbon nanotubes (CNTs), with analytic calculations and electromagnetic eigenmode simulations. A range of acceleration gradients and cutoffs of the x-ray power (the lowest power limit to overcome the Bremsstrahlung radiation losses) are characterized in terms of the lattice constants, unit cell sizes, and photon energies. The parametric analysis indicates that the required x-ray power can be reduced to an order of megawatt by replacing crystals with CNTs. Eventually, the equivalent dielectric approximation of a multi-wall nanotube shows that 250–810 MeV muons can be synchronously coupled with x-rays of 0.65–1.32 keV in the accelerating structure.

  15. A split-beam probe-pump-probe scheme for femtosecond time resolved protein X-ray crystallography

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    van Thor, Jasper J.; Madsen, Anders

    2015-01-01T23:59:59.000Z

    In order to exploit the femtosecond pulse duration of X-ray Free-Electron Lasers (XFEL) operating in the hard X-ray regime for ultrafast time-resolved protein crystallography experiments, critical parameters that determine the crystallographic signal-to-noise (I/?I) must be addressed. For single-crystal studies under low absorbed dose conditions, it has been shown that the intrinsic pulse intensity stability as well as mode structure and jitter of this structure, significantly affect the crystallographic signal-to-noise. Here, geometrical parameters are theoretically explored for a three-beam scheme: X-ray probe, optical pump, X-ray probe (or “probe-pump-probe”) which will allow experimental determination of the photo-induced structure factor amplitude differences, ?F,more »in a ratiometric manner, thereby internally referencing the intensity noise of the XFEL source. In addition to a non-collinear split-beam geometry which separates un-pumped and pumped diffraction patterns on an area detector, applying an additional convergence angle to both beams by focusing leads to integration over mosaic blocks in the case of well-ordered stationary protein crystals. Ray-tracing X-ray diffraction simulations are performed for an example using photoactive yellow protein crystals in order to explore the geometrical design parameters which would be needed. The specifications for an X-ray split and delay instrument that implements both an offset angle and focused beams are discussed, for implementation of a probe-pump-probe scheme at the European XFEL. We discuss possible extension of single crystal studies to serial femtosecond crystallography, particularly in view of the expected X-ray damage and ablation due to the first probe pulse.« less

  16. Domain wall motion and electromechanical strain in lead-free piezoelectrics: Insight from the model system (1 ? x)Ba(Zr{sub 0.2}Ti{sub 0.8})O{sub 3}–x(Ba{sub 0.7}Ca{sub 0.3})TiO{sub 3} using in situ high-energy X-ray diffraction during application of electric fields

    SciTech Connect (OSTI)

    Tutuncu, Goknur [Department of Materials Science and Engineering, University of Florida, Gainesville, Florida 32611 (United States); Li, Binzhi [Department of Chemical Engineering and Materials Science, University of California, Davis, Davis, California 95616 (United States); Bowman, Keith [Illinois Institute of Technology, Armour College of Engineering, Chicago, Illinois 60616 (United States); School of Materials Engineering, Purdue University, West Lafayette, Indiana 47907 (United States); Jones, Jacob L., E-mail: JacobJones@ncsu.edu [Department of Materials Science and Engineering, North Carolina State University, Raleigh, North Carolina 27695 (United States)

    2014-04-14T23:59:59.000Z

    The piezoelectric compositions (1 ? x)Ba(Zr{sub 0.2}Ti{sub 0.8})O{sub 3}–x(Ba{sub 0.7}Ca{sub 0.3})TiO{sub 3} (BZT-xBCT) span a model lead-free morphotropic phase boundary (MPB) between room temperature rhombohedral and tetragonal phases at approximately x?=?0.5. In the present work, in situ X-ray diffraction measurements during electric field application are used to elucidate the origin of electromechanical strain in several compositions spanning the tetragonal compositional range 0.6???x???0.9. As BCT concentration decreases towards the MPB, the tetragonal distortion (given by c/a-1) decreases concomitantly with an increase in 90° domain wall motion. The increase in observed macroscopic strain is predominantly attributed to the increased contribution from 90° domain wall motion. The results demonstrate that domain wall motion is a significant factor in achieving high strain and piezoelectric coefficients in lead-free polycrystalline piezoelectrics.

  17. Fabrication process for a gradient index x-ray lens

    DOE Patents [OSTI]

    Bionta, Richard M. (Livermore, CA); Makowiecki, Daniel M. (Livermore, CA); Skulina, Kenneth M. (Livermore, CA)

    1995-01-01T23:59:59.000Z

    A process for fabricating high efficiency x-ray lenses that operate in the 0.5-4.0 keV region suitable for use in biological imaging, surface science, and x-ray lithography of integrated circuits. The gradient index x-ray optics fabrication process broadly involves co-sputtering multi-layers of film on a wire, followed by slicing and mounting on block, and then ion beam thinning to a thickness determined by periodic testing for efficiency. The process enables the fabrication of transmissive gradient index x-ray optics for the 0.5-4.0 keV energy range. This process allows the fabrication of optical elements for the next generation of imaging and x-ray lithography instruments m the soft x-ray region.

  18. Fabrication process for a gradient index x-ray lens

    DOE Patents [OSTI]

    Bionta, R.M.; Makowiecki, D.M.; Skulina, K.M.

    1995-01-17T23:59:59.000Z

    A process is disclosed for fabricating high efficiency x-ray lenses that operate in the 0.5-4.0 keV region suitable for use in biological imaging, surface science, and x-ray lithography of integrated circuits. The gradient index x-ray optics fabrication process broadly involves co-sputtering multi-layers of film on a wire, followed by slicing and mounting on block, and then ion beam thinning to a thickness determined by periodic testing for efficiency. The process enables the fabrication of transmissive gradient index x-ray optics for the 0.5-4.0 keV energy range. This process allows the fabrication of optical elements for the next generation of imaging and x-ray lithography instruments in the soft x-ray region. 13 figures.

  19. Density gradient free electron collisionally excited X-ray laser

    DOE Patents [OSTI]

    Campbell, Edward M. (Pleasanton, CA); Rosen, Mordecai D. (Berkeley, CA)

    1989-01-01T23:59:59.000Z

    An operational X-ray laser (30) is provided that amplifies 3p-3s transition X-ray radiation along an approximately linear path. The X-ray laser (30) is driven by a high power optical laser. The driving line focused optical laser beam (32) illuminates a free-standing thin foil (34) that may be associated with a substrate (36) for improved structural integrity. This illumination produces a generally cylindrically shaped plasma having an essentially uniform electron density and temperature, that exists over a long period of time, and provides the X-ray laser gain medium. The X-ray laser (30) may be driven by more than one optical laser beam (32, 44). The X-ray laser (30) has been successfully demonstrated to function in a series of experimental tests.

  20. Density gradient free electron collisionally excited x-ray laser

    DOE Patents [OSTI]

    Campbell, E.M.; Rosen, M.D.

    1984-11-29T23:59:59.000Z

    An operational x-ray laser is provided that amplifies 3p-3s transition x-ray radiation along an approximately linear path. The x-ray laser is driven by a high power optical laser. The driving line focused optical laser beam illuminates a free-standing thin foil that may be associated with a substrate for improved structural integrity. This illumination produces a generally cylindrically shaped plasma having an essentially uniform electron density and temperature, that exists over a long period of time, and provides the x-ray laser gain medium. The x-ray laser may be driven by more than one optical laser beam. The x-ray laser has been successfully demonstrated to function in a series of experimental tests.

  1. Continuous motion scan ptychography: Characterization for increased speed in coherent x-ray imaging

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Deng, Junjing; Nashed, Youssef S. G.; Chen, Si; Phillips, Nicholas W.; Peterka, Tom; Ross, Rob; Vogt, Stefan; Jacobsen, Chris; Vine, David J.

    2015-01-01T23:59:59.000Z

    Ptychography is a coherent diffraction imaging (CDI) method for extended objects in which diffraction patterns are acquired sequentially from overlapping coherent illumination spots. The object’s complex transmission function can be reconstructed from those diffraction patterns at a spatial resolution limited only by the scattering strength of the object and the detector geometry. Most experiments to date have positioned the illumination spots on the sample using a move-settle-measure sequence in which the move and settle steps can take longer to complete than the measure step. We describe here the use of a continuous “fly-scan” mode for ptychographic data collection in whichmore »the sample is moved continuously, so that the experiment resembles one of integrating the diffraction patterns from multiple probe positions. This allows one to use multiple probe mode reconstruction methods to obtain an image of the object and also of the illumination function. We show in simulations, and in x-ray imaging experiments, some of the characteristics of fly-scan ptychography, including a factor of 25 reduction in the data acquisition time. This approach will become increasingly important as brighter x-ray sources are developed, such as diffraction limited storage rings.« less

  2. Systems and methods for detecting an image of an object by use of an X-ray beam having a polychromatic distribution

    DOE Patents [OSTI]

    Parham, Christopher; Zhong, Zhong; Pisano, Etta; Connor, Dean; Chapman, Leroy D.

    2010-06-22T23:59:59.000Z

    Systems and methods for detecting an image of an object using an X-ray beam having a polychromatic energy distribution are disclosed. According to one aspect, a method can include detecting an image of an object. The method can include generating a first X-ray beam having a polychromatic energy distribution. Further, the method can include positioning a single monochromator crystal in a predetermined position to directly intercept the first X-ray beam such that a second X-ray beam having a predetermined energy level is produced. Further, an object can be positioned in the path of the second X-ray beam for transmission of the second X-ray beam through the object and emission from the object as a transmitted X-ray beam. The transmitted X-ray beam can be directed at an angle of incidence upon a crystal analyzer. Further, an image of the object can be detected from a beam diffracted from the analyzer crystal.

  3. Legacy of the X-Ray Laser Program

    SciTech Connect (OSTI)

    Nilsen, J.

    1993-08-06T23:59:59.000Z

    The X-Ray Laser Program has evolved from a design effort focusing on developing a Strategic Defense Initiative weapon that protects against Soviet ICBMs to a scientific project that is producing new technologies for industrial and medical research. While the great technical successes and failures of the X-ray laser itself cannot be discussed, this article presents the many significant achievements made as part of the X-ray laser effort that are now being used for other applications at LLNL.

  4. Sum rules for polarization-dependent x-ray absorption

    SciTech Connect (OSTI)

    Ankudinov, A.; Rehr, J.J. (Department of Physics, FM-15, University of Washington, Seattle, Washington 98195 (United States))

    1995-01-01T23:59:59.000Z

    A complete set of sum rules is obtained for polarization-dependent x-ray-absorption fine structure and x-ray circular magnetic dichroism (CMD), analogous to those for CMD derived by Thole [ital et] [ital al]. These sum rules relate x-ray-absorption coefficients to the ground-state expectation values of various operators. Problems with applying these sum rules are discussed.

  5. A laser triggered vacuum spark x-ray lithography source

    E-Print Network [OSTI]

    Keating, Richard Allen

    1987-01-01T23:59:59.000Z

    ionized state or the physical processes occurring 15 in a high temperature plasma. There are many advantages to the use of the vacuum spark as an x-ray source; the simplicity of the machine is one. The x-ray output is within the range usable for x-ray... spark apparatus ha- been studied here to determine its applicability to x-ray lithography. A capacitor which stored approximately 3 KJ supplied most of the energy for the plasma. A Nd-YAG laser was used to supply electrons and metallic atoms...

  6. X-ray compass for determining device orientation

    DOE Patents [OSTI]

    Da Silva, Luiz B. (Danville, CA); Matthews, Dennis L. (Moss Beach, CA); Fitch, Joseph P. (Livermore, CA); Everett, Matthew J. (Pleasanton, CA); Colston, Billy W. (Livermore, CA); Stone, Gary F. (Livermore, CA)

    1999-01-01T23:59:59.000Z

    An apparatus and method for determining the orientation of a device with respect to an x-ray source. In one embodiment, the present invention is coupled to a medical device in order to determine the rotational orientation of the medical device with respect to the x-ray source. In such an embodiment, the present invention is comprised of a scintillator portion which is adapted to emit photons upon the absorption of x-rays emitted from the x-ray source. An x-ray blocking portion is coupled to the scintillator portion. The x-ray blocking portion is disposed so as to vary the quantity of x-rays which penetrate the scintillator portion based upon the particular rotational orientation of the medical device with respect to the x-ray source. A photon transport mechanism is also coupled to the scintillator portion. The photon transport mechanism is adapted to pass the photons emitted from the scintillator portion to an electronics portion. By analyzing the quantity of the photons, the electronics portion determines the rotational orientation of the medical device with respect to the x-ray source.

  7. X-ray compass for determining device orientation

    DOE Patents [OSTI]

    Da Silva, L.B.; Matthews, D.L.; Fitch, J.P.; Everett, M.J.; Colston, B.W.; Stone, G.F.

    1999-06-15T23:59:59.000Z

    An apparatus and method for determining the orientation of a device with respect to an x-ray source are disclosed. In one embodiment, the present invention is coupled to a medical device in order to determine the rotational orientation of the medical device with respect to the x-ray source. In such an embodiment, the present invention is comprised of a scintillator portion which is adapted to emit photons upon the absorption of x-rays emitted from the x-ray source. An x-ray blocking portion is coupled to the scintillator portion. The x-ray blocking portion is disposed so as to vary the quantity of x-rays which penetrate the scintillator portion based upon the particular rotational orientation of the medical device with respect to the x-ray source. A photon transport mechanism is also coupled to the scintillator portion. The photon transport mechanism is adapted to pass the photons emitted from the scintillator portion to an electronics portion. By analyzing the quantity of the photons, the electronics portion determines the rotational orientation of the medical device with respect to the x-ray source. 25 figs.

  8. Unexpected Angular Dependence of X-Ray Magnetic Linear Dichroism

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    axes must be taken into account for accurate interpretation of XMLD data. Magnetism and X Rays The ancient Greeks and also the Chinese knew about strange and rare...

  9. Generation of Coherent X-Ray Radiation Through Modulation Compression

    E-Print Network [OSTI]

    Qiang, Ji

    2011-01-01T23:59:59.000Z

    ultra-short coherent X-ray radiation by controlling the fraction of the beam that can be properly unchirped using a few-cycle laser

  10. The Daguerreotype and the X-ray: A Deep Look

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    - likely will play a crucial role in future scientific breakthroughs. Last week, hers was the first daguerreotype to undergo powerful x-ray analysis in a collaboration...

  11. Reciprocal space mapping of epitaxial materials using position-sensitive x-ray detection

    SciTech Connect (OSTI)

    Lee, S.R.; Doyle, B.L.; Drummond, T.J.; Medernach, J.W.; Schneider, R.P. Jr.

    1994-10-01T23:59:59.000Z

    Reciprocal space mapping can be efficiently carried out using a position-sensitive x-ray detector (PSD) coupled to a traditional double-axis diffractometer. The PSD offers parallel measurement of the total scattering angle of all diffracted x-rays during a single rocking-curve scan. As a result, a two-dimensional reciprocal space map can be made in a very short time similar to that of a one-dimensional rocking-curve scan. Fast, efficient reciprocal space mapping offers numerous routine advantages to the x-ray diffraction analyst. Some of these advantages are the explicit differentiation of lattice strain from crystal orientation effects in strain-relaxed heteroepitaxial layers; the nondestructive characterization of the size, shape and orientation of nanocrystalline domains in ordered-alloy epilayers; and the ability to measure the average size and shape of voids in porous epilayers. Here, the PSD-based diffractometer is described, and specific examples clearly illustrating the advantages of complete reciprocal space analysis are presented.

  12. Combining THz laser excitation with resonant soft X-ray scattering at the Linac Coherent Light Source

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Turner, Joshua J.; Dakovski, Georgi L.; Hoffmann, Matthias C.; Hwang, Harold Y.; Zarem, Alex; Schlotter, William F.; Moeller, Stefan; Minitti, Michael P.; Staub, Urs; Johnson, Steven; et al

    2015-05-01T23:59:59.000Z

    This paper describes the development of new instrumentation at the Linac Coherent Light Source for conducting THz excitation experiments in an ultra high vacuum environment probed by soft X-ray diffraction. This consists of a cantilevered, fully motorized mirror system which can provide 600 kV cm?¹ electric field strengths across the sample and an X-ray detector that can span the full Ewald sphere with in-vacuum motion. The scientific applications motivated by this development, the details of the instrument, and spectra demonstrating the field strengths achieved using this newly developed system are discussed.

  13. Multi-Scaled Microstructures in Natural Rubber Characterized by Synchrotron X-ray Scattering and Optical Microscopy

    SciTech Connect (OSTI)

    Toki , S.; Hsiao, B; Amnuaypornsri , S; Sakdapipanich, J; Tanaka, Y

    2008-01-01T23:59:59.000Z

    Multi-scaled microstructures induced by natural impurities (i.e., proteins, phospholipids, carbohydrates) in natural rubber (NR) were investigated by synchrotron small-angle X-ray scattering (SAXS), wide-angle X-ray diffraction (WAXD), and optical microscopy using several kinds of untreated and chemically treated un-vulcanized samples. These microstructures include large aggregates (size less than 50 m), well-defined crystals (size less than a few 10 m), and micelles (size much less than 10 m). In un-vulcanized NR samples, even though the concentrations of natural impurities are relatively low, the dispersion of these microstructures significantly affects the mechanical properties

  14. 2011 U.S. National School on Neutron and X-ray Scattering

    SciTech Connect (OSTI)

    Lang, Jonathan [Argonne National Laboratory (ANL); te Vethuis, Suzanne [Argonne National Laboratory (ANL); Ekkebus, Allen E [ORNL; Chakoumakos, Bryan C [ORNL; Budai, John D [ORNL

    2012-01-01T23:59:59.000Z

    The 13th annual U.S. National School on Neutron and X-ray Scattering was held June 11 to 25, 2011, at both Oak Ridge and Argonne National Laboratories. This school brought together 65 early career graduate students from 56 different universities in the US and provided them with a broad introduction to the techniques available at the major large-scale neutron and synchrotron x-ray facilities. This school is focused primarily on techniques relevant to the physical sciences, but also touches on cross-disciplinary bio-related scattering measurements. During the school, students received lectures by over 30 researchers from academia, industry, and national laboratories and participated in a number of short demonstration experiments at Argonne's Advanced Photon Source (APS) and Oak Ridge's Spallation neutron Source (SNS) and High Flux Isotope Reactor (HFIR) facilities to get hands-on experience in using neutron and synchrotron sources. The first week of this year's school was held at Oak Ridge National Lab, where Lab director Thom Mason welcomed the students and provided a shitorical perspective of the neutron and x-ray facilities both at Oak Ridge and Argonne. The first few days of the school were dedicated to lectures laying out the basics of scattering theory and the differences and complementarity between the neutron and x-ray probes given by Sunil Sinha. Jack Carpenter provided an introduction into how neutrons are generated and detected. After this basic introduction, the students received lectures each morning on specific techniques and conducted demonstration experiments each afternoon on one of 15 different instruments at either the SNS or HFIR. Some of the topics covered during this week of the school included inelastic neutron scattering by Bruce Gaulin, x-ray and neutron reflectivity by Chuck Majkrazak, small-angle scattering by Volker Urban, powder diffraction by Ashfia Huq and diffuse scattering by Gene Ice.

  15. X-ray photoelectron spectroscopy of gallium nitride films grown by radical-beam gettering epitaxy

    SciTech Connect (OSTI)

    Rogozin, I. V. [Berdyansk State Pedagogical University (Ukraine)], E-mail: rogozin@bdpu.org; Kotlyarevsky, M. B. [Academy of Management and Information Technology (Ukraine)

    2007-05-15T23:59:59.000Z

    Thin GaN films were grown on GaAs(111) substrates by radical-beam gettering epitaxy. The structural quality of the films was studied by high-resolution x-ray diffraction. The chemical composition of the GaAs surface and GaN film was studied by x-ray photoelectron spectroscopy. It is shown that Ga-N and As-N bonds are formed on the GaAs surface at initial growth stages at low temperatures. The state of the film-substrate interface was studied. It was found that prolonged annealing of GaN films in nitrogen radicals shifts the composition to nitrogen excess.

  16. X-ray laser system, x-ray laser and method

    DOE Patents [OSTI]

    London, Richard A. (Oakland, CA); Rosen, Mordecai D. (Berkeley, CA); Strauss, Moshe (Omer, IL)

    1992-01-01T23:59:59.000Z

    Disclosed is an x-ray laser system comprising a laser containing generating means for emitting short wave length radiation, and means external to said laser for energizing said generating means, wherein when the laser is in an operative mode emitting radiation, the radiation has a transverse coherence length to width ratio of from about 0.05 to 1. Also disclosed is a method of adjusting the parameters of the laser to achieve the desired coherence length to laser width ratio.

  17. Constraints on jet X-ray emission in low/hard state X-ray binaries

    E-Print Network [OSTI]

    Thomas J. Maccarone

    2005-03-31T23:59:59.000Z

    We show that the combination of the similarities between the X-ray properties of low luminosity accreting black holes and accreting neutron stars, combined with the differences in their radio properties argues that the X-rays from these systems are unlikely to be formed in the relativistic jets. Specifically, the spectra of extreme island state neutron stars and low/hard state black holes are known to be indistinguishable, while the power spectra from these systems are known to show only minor differences beyond what would be expected from scaling the characteristic variability frequencies by the mass of the compact object. The spectral and temporal similarities thus imply a common emission mechanism that has only minor deviations from having all key parameters scaling linearly with the mass of the compact object, while we show that this is inconsistent with the observations that the radio powers of neutron stars are typically about 30 times lower than those of black holes at the same X-ray luminosity. We also show that an abrupt luminosity change would be expected when a system makes a spectral state transition from a radiatively inefficient jet dominated accretion flow to a thin disk dominated flow, but that such a change is not seen.

  18. Isotropic star in low-mass X-ray binaries and X-ray pulsars

    E-Print Network [OSTI]

    Mehedi Kalam; Sk. Monowar Hossein; Sajahan Molla

    2014-10-01T23:59:59.000Z

    We present a model for compact stars in the low mass X-ray binaries(LMXBs) and X-ray pulsars using a metric given by John J. Matese and Patrick G. Whitman \\citep{Matese and Whitman1980}. Here the field equations are reduced to a system of two algebraic equations considering the isotropic pressure. Compact star candidates 4U 1820-30(radius=10km) in LMXBs, and Her X-1(radius=7.7km), SAX J 1808.4-3658(SS1)(radius=7.07km) and SAX J 1808.4-3658(SS2)(radius=6.35km) in X-ray pulsars satisfy all the energy conditions, TOV-equation and stability condition. From our model, we have derived mass($M$), central density($\\rho_{0}$), suface density($\\rho_{b}$), central pressure($p_{0}$), surface pressure($p_{b}$) and surface red-shift($Z_{s}$) of the above mentioned stars, which are very much consistant with the observed/reported datas\\citep{N. K. Glendenning1997,Gondek2000}. We have also observe the adiabatic index($\\gamma$>4/3) of the above steller objects.

  19. Large angle solid state position sensitive x-ray detector system

    DOE Patents [OSTI]

    Kurtz, D.S.; Ruud, C.O.

    1998-07-21T23:59:59.000Z

    A method and apparatus are disclosed for x-ray measurement of certain properties of a solid material. In distinction to known methods and apparatus, this invention employs a specific fiber-optic bundle configuration, termed a reorganizer, itself known for other uses, for coherently transmitting visible light originating from the scintillation of diffracted x-radiation from the solid material gathered along a substantially one dimensional linear arc, to a two-dimensional photo-sensor array. The two-dimensional photodetector array, with its many closely packed light sensitive pixels, is employed to process the information contained in the diffracted radiation and present the information in the form of a conventional x-ray diffraction spectrum. By this arrangement, the angular range of the combined detector faces may be increased without loss of angular resolution. Further, the prohibitively expensive coupling together of a large number of individual linear diode photodetectors, which would be required to process signals generated by the diffracted radiation, is avoided. 7 figs.

  20. Large angle solid state position sensitive x-ray detector system

    DOE Patents [OSTI]

    Kurtz, David S. (State College, PA); Ruud, Clay O. (State College, PA)

    1998-01-01T23:59:59.000Z

    A method and apparatus for x-ray measurement of certain properties of a solid material. In distinction to known methods and apparatus, this invention employs a specific fiber-optic bundle configuration, termed a reorganizer, itself known for other uses, for coherently transmitting visible light originating from the scintillation of diffracted x-radiation from the solid material gathered along a substantially one dimensional linear arc, to a two-dimensional photo-sensor array. The two-dimensional photodetector array, with its many closely packed light sensitive pixels, is employed to process the information contained in the diffracted radiation and present the information in the form of a conventional x-ray diffraction spectrum. By this arrangement, the angular range of the combined detector faces may be increased without loss of angular resolution. Further, the prohibitively expensive coupling together of a large number of individual linear diode photodetectors, which would be required to process signals generated by the diffracted radiation, is avoided.

  1. Large angle solid state position sensitive x-ray detector system

    DOE Patents [OSTI]

    Kurtz, D.S.; Ruud, C.O.

    1998-03-03T23:59:59.000Z

    A method and apparatus for x-ray measurement of certain properties of a solid material are disclosed. In distinction to known methods and apparatus, this invention employs a specific fiber-optic bundle configuration, termed a reorganizer, itself known for other uses, for coherently transmitting visible light originating from the scintillation of diffracted x-radiation from the solid material gathered along a substantially one dimensional linear arc, to a two-dimensional photo-sensor array. The two-dimensional photodetector array, with its many closely packed light sensitive pixels, is employed to process the information contained in the diffracted radiation and present the information in the form of a conventional x-ray diffraction spectrum. By this arrangement, the angular range of the combined detector faces may be increased without loss of angular resolution. Further, the prohibitively expensive coupling together of a large number of individual linear diode photodetectors, which would be required to process signals generated by the diffracted radiation, is avoided. 7 figs.

  2. Ultrafast x-rays: radiographing magnetism Project overview

    E-Print Network [OSTI]

    Haviland, David

    , head of the ultrafast magnetism group. Stanford PULSE is a worldwide renowned centre for ultrafast1 Ultrafast x-rays: radiographing magnetism Project overview The main purpose of the proposed, it is now possible to achieve x-ray pulses that are a few femtoseconds long and that are focused within

  3. High resolution energy-sensitive digital X-ray

    DOE Patents [OSTI]

    Nygren, David R. (Berkeley, CA)

    1995-01-01T23:59:59.000Z

    An apparatus and method for detecting an x-ray and for determining the depth of penetration of an x-ray into a semiconductor strip detector. In one embodiment, a semiconductor strip detector formed of semiconductor material is disposed in an edge-on orientation towards an x-ray source such that x-rays From the x-ray source are incident upon and substantially perpendicular to the front edge of the semiconductor strip detector. The semiconductor strip detector is formed of a plurality of segments. The segments are coupled together in a collinear arrangement such that the semiconductor strip detector has a length great enough such that substantially all of the x-rays incident on the front edge of the semiconductor strip detector interact with the semiconductor material which forms the semiconductor strip detector. A plurality of electrodes are connected to the semiconductor strip detect or such that each one of the of semiconductor strip detector segments has at least one of the of electrodes coupled thereto. A signal processor is also coupled to each one of the electrodes. The present detector detects an interaction within the semiconductor strip detector, between an x-ray and the semiconductor material, and also indicates the depth of penetration of the x-ray into the semiconductor strip detector at the time of the interaction.

  4. Shad-o-Snap X-Ray Camera Hardware Manual

    E-Print Network [OSTI]

    -o-Snap x-ray camera is a complete, stand-alone x-ray imaging device featuring "smart" microprocessor-controlled camera electronics and a convenient USB interface. The plug- and-play interface allows easy control by the silicon photodiodes. The Shad-o-Snap camera also includes electronics to digitize the video signal

  5. Measurement and characterization of x-ray spot size

    SciTech Connect (OSTI)

    Mueller, K.H.

    1989-01-01T23:59:59.000Z

    In planning an x-ray imaging experiment one must have an accurate model of the imaging system to obtain optimum results. The blurring caused by the finite size of the x-ray source is often the least understood element in the system. We have developed experimental and analytical methods permitting accurate measurement and modeling of the x-ray source. The model offers a simple and accurate way to optimize the radiographic geometry for any given experimental requirement (i.e., resolution and dose at detector). Any text on radiography will mention the effects of the finite size of the x-ray source on image quality and how one can minimize this influence by the choice of a small radiographic magnification. The film blur (independent of the source blur) is often treated as a single number and combined with an effective blur dimension for the x-ray source to give a total blur on the film. In this paper, we will develop a treatment of x-ray sources based on the modulation transfer function (MTF). This approach allows us to infer the spatial distribution function of the electron beam that produces the bremsstrahlung x-rays and to predict the performance of an x-ray imaging system if we know the MTF of the detector. This treatment is much more accurate than a single number characterization. 4 refs., 7 figs.

  6. Fourteenth National School on Neutron and X-ray Scattering

    E-Print Network [OSTI]

    Pennycook, Steve

    Fourteenth National School on Neutron and X-ray Scattering August 12 - 25, 2012 at Argonne National of the National School on Neutron and X-ray Scattering is to educate graduate students on the utilization of major Ridge National Laboratory's Neutron Scattering Science Division. Scientific Directors: Jonathan C. Lang

  7. Neutron and X-ray Scattering Study of Magnetic Manganites

    E-Print Network [OSTI]

    Boothroyd, Andrew

    Neutron and X-ray Scattering Study of Magnetic Manganites Graeme Eoin Johnstone A Thesis submitted are performed using a variety of neutron scattering and x-ray scattering techniques. The electronic ground for analysing the results of the polarised neutron scattering experiment. There are a large number of people who

  8. Tenth National School on Neutron and X-ray Scattering

    E-Print Network [OSTI]

    Pennycook, Steve

    Tenth National School on Neutron and X-ray Scattering September 24 - October 11, 2008 at Argonne of the National School on Neutron and X-ray Scattering is to educate graduate students on the utilization of major National Laboratory's Neutron Scattering Science Division. Scientific Directors: Jonathan C. Lang, Suzanne

  9. National School on Neutron and X-ray Scattering

    E-Print Network [OSTI]

    15th National School on Neutron and X-ray Scattering August 10 - 24, 2013 at Argonne National of the National School on Neutron and X-ray Scattering is to educate graduate students on the utilization of major Ridge National Laboratory's Neutron Scattering Science Division. Scientific Directors: Jonathan C. Lang

  10. Thirteenth National School on Neutron and X-ray Scattering

    E-Print Network [OSTI]

    Thirteenth National School on Neutron and X-ray Scattering June 11 ­ June 25, 2011 at Argonne of the National School on Neutron and X-ray Scattering is to educate graduate students on the utilization of major National Laboratory's Neutron Scattering Science Division. Scientific Directors: Jonathan C. Lang, Suzanne

  11. Sixteenth National School on Neutron and X-ray Scattering

    E-Print Network [OSTI]

    Pennycook, Steve

    Sixteenth National School on Neutron and X-ray Scattering June 14-28, 2014 at Argonne National of the National School on Neutron and X-ray Scattering is to educate graduate students on the utilization of major's Neutron Scattering Science Division. Scientific Directors: Suzanne G.E. te Velthuis, Esen Ercan Alp

  12. Twelfth National School on Neutron and X-ray Scattering

    E-Print Network [OSTI]

    Pennycook, Steve

    Twelfth National School on Neutron and X-ray Scattering June 12 ­ June 26, 2010 at Argonne National of the National School on Neutron and X-ray Scattering is to educate graduate students on the utilization of major National Laboratory's Neutron Scattering Science Division. Scientific Directors: Jonathan C. Lang, Suzanne

  13. National School on Neutron and X-ray Scattering

    E-Print Network [OSTI]

    Pennycook, Steve

    National School on Neutron and X-ray Scattering May 30 ­ June 13, 2009 at Argonne National of the National School on Neutron and X-ray Scattering is to educate graduate students on the utilization of major National Laboratory's Neutron Scattering Science Division. Scientific Directors: Jonathan C. Lang, Suzanne

  14. Electromagnetic Application: X-RAY Alawi H. Ba-Surrah

    E-Print Network [OSTI]

    Masoudi, Husain M.

    , Pulyui published high-quality x-ray images in journals in Paris and London. · Nikola Tesla In April 1887, Nikola Tesla began to investigate X-rays using high voltages and tubes of his own design, as well. The principle behind Tesla's device is called the Bremsstrahlung process, in which a high-energy secondary X

  15. Chandra X-ray Analysis of Galaxy Cluster A168

    E-Print Network [OSTI]

    Yanbin Yang; Zhiying Huo; Xu Zhou; Suijian Xue; Shude Mao; Jun Ma; Jiansheng Chen

    2004-06-29T23:59:59.000Z

    We present Chandra X-ray observations of galaxy cluster A168 (z=0.045). Two X-ray peaks with a projected distance of 676 kpc are found to be located close to two dominant galaxies, respectively. Both peaks are significantly offset from the peak of the number density distribution of galaxies. This suggests that A168 consists of two subclusters, a northern subcluster (A168N) and a southern subcluster (A168S). Further X-ray imaging analysis reveals that (1) the X-ray isophotes surrounding the two X-ray peaks are heavily distorted, (2) an elongated and ontinuous filament connects the two X-ray peaks. These suggest that strong interactions have occurred between the two subclusters. Spectral analysis shows that A168 has a mean temperature of 2.53 +/- 0.09 keV and a mean metallicity of 0.31 +/- 0.04 Z_{solar}. The metallicity is roughly a constant across the cluster but the temperature shows some systematic variations. Most X-ray, optical and radio properties of A168 are consistent with it being an off-axis merger several Gyrs after a core passage, although detailed numerical simulations are required to see whether the observed properties, in particular the significant offset between the optical and X-ray centers, can be reproduced in such a scenario.

  16. Millisecond oscillations during thermonuclear X-ray bursts

    E-Print Network [OSTI]

    Muno, Michael Patrick, 1975-

    2002-01-01T23:59:59.000Z

    I analyze 68 oscillation trains detected in a search of 159 thermonuclear bursts from eight neutron star X-ray binaries observed with the Rossi X-ray Timing Explorer. I use all data that were public as of September 2001. ...

  17. Broadband high resolution X-ray spectral analyzer

    DOE Patents [OSTI]

    Silver, E.H.; Legros, M.; Madden, N.W.; Goulding, F.; Landis, D.

    1998-07-07T23:59:59.000Z

    A broad bandwidth high resolution X-ray fluorescence spectrometer has a performance that is superior in many ways to those currently available. It consists of an array of 4 large area microcalorimeters with 95% quantum efficiency at 6 keV and it produces X-ray spectra between 0.2 keV and 7 keV with an energy resolution of 7 to 10 eV. The resolution is obtained at input count rates per array element of 10 to 50 Hz in real-time, with analog pulse processing and thermal pile-up rejection. This performance cannot be matched by currently available X-ray spectrometers. The detectors are incorporated into a compact and portable cryogenic refrigerator system that is ready for use in many analytical spectroscopy applications as a tool for X-ray microanalysis or in research applications such as laboratory and astrophysical X-ray and particle spectroscopy. 6 figs.

  18. Broadband high resolution X-ray spectral analyzer

    DOE Patents [OSTI]

    Silver, Eric H. (Berkeley, CA); Legros, Mark (Berkeley, CA); Madden, Norm W. (Livermore, CA); Goulding, Fred (Lafayette, CA); Landis, Don (Pinole, CA)

    1998-01-01T23:59:59.000Z

    A broad bandwidth high resolution x-ray fluorescence spectrometer has a performance that is superior in many ways to those currently available. It consists of an array of 4 large area microcalorimeters with 95% quantum efficiency at 6 keV and it produces x-ray spectra between 0.2 keV and 7 keV with an energy resolution of 7 to 10 eV. The resolution is obtained at input count rates per array element of 10 to 50 Hz in real-time, with analog pulse processing and thermal pile-up rejection. This performance cannot be matched by currently available x-ray spectrometers. The detectors are incorporated into a compact and portable cryogenic refrigerator system that is ready for use in many analytical spectroscopy applications as a tool for x-ray microanalysis or in research applications such as laboratory and astrophysical x-ray and particle spectroscopy.

  19. X-Ray Observations of Gamma-Ray Burst Afterglows

    E-Print Network [OSTI]

    Filippo Frontera

    2004-06-25T23:59:59.000Z

    The discovery by the BeppoSAX satellite of X-ray afterglow emission from the gamma-ray burst which occurred on 28 February 1997 produced a revolution in our knowledge of the gamma-ray burst phenomenon. Along with the discovery of X-ray afterglows, the optical afterglows of gamma-ray bursts were discovered and the distance issue was settled, at least for long $\\gamma$-ray bursts. The 30 year mystery of the gamma-ray burst phenomenon is now on the way to solution. Here I rewiew the observational status of the X-ray afterglow emission, its mean properties (detection rate, continuum spectra, line features, and light curves), and the X-ray constraints on theoretical models of gamma-ray bursters and their progenitors. I also discuss the early onset afterglow emission, the remaining questions, and the role of future X-ray afterglow observations.

  20. Deep x-ray lithography for micromechanics

    SciTech Connect (OSTI)

    Christenson, T.R. [Sandia National Labs., Albuquerque, NM (United States); Guckel, H. [Wisconsin Univ., Madison, WI (United States). Dept. of Electrical and Computer Engineering

    1995-08-01T23:59:59.000Z

    Extensions of the German LIGA process have brought about fabrication capability suitable for cost effective production of precision engineered components. The process attributes allow fabrication of mechanical components which are not capable of being made via conventional subtractive machining methods. Two process improvements have been responsible for this extended capability which involve the areas of thick photoresist application and planarization via precision lapping. Application of low-stress x-ray photoresist has been achieved using room temperature solvent bonding of a preformed photoresist sheet. Precision diamond lapping and polishing has provided a flexible process for the planarization of a wide variety of electroplated metals in the presence of photoresist. Exposure results from the 2.5 GeV National Synchrotron Light Source storage ring at Brookhaven National Laboratory have shown that structural heights of several millimeter and above are possible. The process capabilities are also well suited for microactuator fabrication. Linear and rotational magnetic microactuators have been constructed which use coil winding technology with LIGA fabricated coil forms. Actuator output forces of 1 milliNewton have been obtained with power dissipation on the order of milliWatts. A rotational microdynamometer system which is capable of measuring torque-speed data is also discussed.

  1. X-ray Emission from Massive StarsX-ray Emission from Massive Stars David CohenDavid Cohen

    E-Print Network [OSTI]

    Cohen, David

    X-ray Emission from Massive StarsX-ray Emission from Massive Stars David CohenDavid Cohen/s)Velocity (km/s) #12;absorption emission emission occulted emission emission UV telescope side side front back #12;absorption emission emission occulted emission emission UV telescope side side front back #12;The

  2. AugEX: AUGER ELECTRON AND X-RAY SPECTROMETER ON CHANDRAYAAN-2 ROVER

    E-Print Network [OSTI]

    Bapat, Bhas

    for determining elemental composition which have a space heritage X-Ray Fluorescence (XRF) Particle-induced X-ray fluorescence (XRF) Expected Advantage: cover low Z elements with higher sensitivity than XRF or PIXE. ACHARYA-ray absorption or charged particle bombardment X-ray emission induced by X-ray absorption: XRF X-ray emission

  3. Soft-x-ray spectroscopy study of nanoscale materials

    SciTech Connect (OSTI)

    Guo, J.-H.

    2005-07-30T23:59:59.000Z

    The ability to control the particle size and morphology of nanoparticles is of crucial importance nowadays both from a fundamental and industrial point of view considering the tremendous amount of high-tech applications. Controlling the crystallographic structure and the arrangement of atoms along the surface of nanostructured material will determine most of its physical properties. In general, electronic structure ultimately determines the properties of matter. Soft X-ray spectroscopy has some basic features that are important to consider. X-ray is originating from an electronic transition between a localized core state and a valence state. As a core state is involved, elemental selectivity is obtained because the core levels of different elements are well separated in energy, meaning that the involvement of the inner level makes this probe localized to one specific atomic site around which the electronic structure is reflected as a partial density-of-states contribution. The participation of valence electrons gives the method chemical state sensitivity and further, the dipole nature of the transitions gives particular symmetry information. The new generation synchrotron radiation sources producing intensive tunable monochromatized soft X-ray beams have opened up new possibilities for soft X-ray spectroscopy. The introduction of selectively excited soft X-ray emission has opened a new field of study by disclosing many new possibilities of soft X-ray resonant inelastic scattering. In this paper, some recent findings regarding soft X-ray absorption and emission studies of various nanostructured systems are presented.

  4. An electrochemical cell for in operando studies of lithium/sodium batteries using a conventional x-ray powder diffractometer

    SciTech Connect (OSTI)

    Shen, Yanbin; Pedersen, Erik E.; Christensen, Mogens; Iversen, Bo B., E-mail: bo@chem.au.dk [Center for Materials Crystallography, Department of Chemistry and iNANO, Aarhus University, Aarhus (Denmark)

    2014-10-15T23:59:59.000Z

    An electrochemical cell has been designed for powder X-ray diffraction studies of lithium ion batteries (LIB) and sodium ion batteries (SIB) in operando with high time resolution using a conventional powder X-ray diffractometer. The cell allows for studies of both anode and cathode electrode materials in reflection mode. The cell design closely mimics that of standard battery testing coin cells and allows obtaining powder X-ray diffraction patterns under representative electrochemical conditions. In addition, the cell uses graphite as the X-ray window instead of beryllium, and it is easy to operate and maintain. Test examples on lithium insertion/extraction in two spinel-type LIB electrode materials (Li{sub 4}Ti{sub 5}O{sub 12} anode and LiMn{sub 2}O{sub 4} cathode) are presented as well as first results on sodium extraction from a layered SIB cathode material (Na{sub 0.84}Fe{sub 0.56}Mn{sub 0.44}O{sub 2})

  5. Neutron and x-ray scattering studies of the metallurgical condition and residual stresses in Weldalite welds

    SciTech Connect (OSTI)

    Spooner, S. [Oak Ridge National Lab., TN (United States); Pardue, E.B.S. [Technology for Energy Corp., Knoxville, TN (United States)

    1995-12-31T23:59:59.000Z

    Weldalite is a lithium-containing aluminum alloy which is being considered for aerospace applications because its favorable strength-to-weight ratio. Successful welding of this alloy depends on the control of the metallurgical condition and residual stresses in the heat affected zone. Neutron and x-ray scattering methods of residual stress measurement were applied to plasma arc welds made in aluminum-lithium alloy test panels as part of an evaluation of materials for use in welded structures. In the course of these studies discrepancies between x-ray and neutron results from the heat affected zone (HAZ) of the weld were found. Texture changes and recovery from the cold work, indicated in peak widths, were found in the HAZ as well. The consideration of x-ray and neutron results leads to the conclusion that there is a change in solute composition which modifies the d-spacings in the HAZ which affects the neutron diffraction determination of residual stresses. The composition changes give the appearance of significant compressive strains in the HAZ. This effect and sharp gradients in the texture give severe anomalies in the neutron measurement of residual stress. The use of combined x-ray and neutron techniques and the solution to the minimizing of the neutron diffraction anomalies are discussed.

  6. Real-time x-ray studies of gallium nitride nanodot formation by droplet heteroepitaxy

    SciTech Connect (OSTI)

    Wang Yiyi; Oezcan, Ahmet S.; Sanborn, Christopher; Ludwig, Karl F.; Bhattacharyya, Anirban; Chandrasekaran, Ramya; Moustakas, Theodore D.; Zhou Lin; Smith, David J. [Physics Department, Boston University, Boston, Massachusetts 02215 (United States); Department of Electrical and Computer Engineering, Boston University, Boston, Massachusetts 02215 (United States); Department of Physics, Arizona State University, Tempe, Arizona 85287, USA and School of Materials, Arizona State University, Tempe, Arizona 85287 (United States)

    2007-10-01T23:59:59.000Z

    Self-organized gallium nitride nanodots have been fabricated using droplet heteroepitaxy on c-plane sapphire by plasma-assisted molecular beam epitaxy at different substrate temperatures and Ga fluxes. Nanoscale Ga droplets were initially formed on the sapphire substrate at high temperatures by Ga deposition from an effusion cell in an ultrahigh vacuum growth chamber. Subsequently, the droplets were converted into GaN nanodots using a nitrogen plasma source. The process was monitored and controlled using real-time grazing-incidence small-angle x-ray scattering. The samples were examined postgrowth by in situ grazing incidence x-ray diffraction and reflection high-energy electron diffraction, which confirmed the epitaxial relationship between the GaN nanodots and the sapphire surface. X-ray diffraction indicated that the wurtzite phase was dominant at higher substrate temperature (710 deg. C), but a mixture of wurtzite and zinc blende phases was present at a substrate temperature of 620 deg. C. Ex situ atomic force microscopy and transmission electron microscopy analyses showed that the dot size distribution was bimodal. A thin GaN continuous layer of {approx} three monolayers thick was observed by transmission electron microscopy on the sample grown at a substrate temperature of 620 deg. C, but no such layer was observed for the substrate temperature of 710 deg. C. This suggests that there is little mobility of Ga atoms in contact with the sapphire substrate at the lower temperature so that they cannot easily diffuse to nearby droplets and instead form a thin layer covering the surface.

  7. Real-Time X-ray Studies of Gallium Nitride Nanodot Formation by Droplet Heteroepitaxy

    SciTech Connect (OSTI)

    Wang,Y.; Ozcan, A.; Sanborn, C.; Ludwig, K.; Bhattacharyya, A.; Chandrasekaran, R.; Moustakas, T.; Zhou, L.; Smith, D.

    2007-01-01T23:59:59.000Z

    Self-organized gallium nitride nanodots have been fabricated using droplet heteroepitaxy on c-plane sapphire by plasma-assisted molecular beam epitaxy at different substrate temperatures and Ga fluxes. Nanoscale Ga droplets were initially formed on the sapphire substrate at high temperatures by Ga deposition from an effusion cell in an ultrahigh vacuum growth chamber. Subsequently, the droplets were converted into GaN nanodots using a nitrogen plasma source. The process was monitored and controlled using real-time grazing-incidence small-angle x-ray scattering. The samples were examined postgrowth by in situ grazing incidence x-ray diffraction and reflection high-energy electron diffraction, which confirmed the epitaxial relationship between the GaN nanodots and the sapphire surface. X-ray diffraction indicated that the wurtzite phase was dominant at higher substrate temperature (710? C), but a mixture of wurtzite and zinc blende phases was present at a substrate temperature of 620? C. Ex situ atomic force microscopy and transmission electron microscopy analyses showed that the dot size distribution was bimodal. A thin GaN continuous layer of ? three monolayers thick was observed by transmission electron microscopy on the sample grown at a substrate temperature of 620? C, but no such layer was observed for the substrate temperature of 710? C. This suggests that there is little mobility of Ga atoms in contact with the sapphire substrate at the lower temperature so that they cannot easily diffuse to nearby droplets and instead form a thin layer covering the surface.

  8. Apparatus for generating x-ray holograms

    DOE Patents [OSTI]

    Rhodes, C.K.; Boyer, K.; Solem, J.C.; Haddad, W.S.

    1990-09-11T23:59:59.000Z

    Apparatus for x-ray microholography of living biological materials. A Fourier transform holographic configuration is described as being most suitable for the 3-dimensional recording of the physical characteristics of biological specimens. The use of a spherical scatterer as a reference and a charge-coupled device two-dimensional detector array placed in the forward direction relative to the incident x-radiation for viewing electromagnetic radiation simultaneously scattered from both the specimen and the reference scatterer permits the ready reconstruction of the details of the specimen from the fringe pattern detected by the charge-coupled device. For example, by using a nickel reference scatter at 4.5 nm, sufficient reference illumination is provided over a wide enough angle to allow similar resolution in both transverse and longitudinal directions. Both laser and synchrotron radiation sources are feasible for generating microholographs. Operation in the water window (2.4 to 4.5 nm) should provide maximum contrast for features of the specimen and spatial resolution on the order of the wavelength of x-radiation should be possible in all three dimensions, which is sufficient for the visualization of many biological features. It is anticipated that the present apparatus will find utility in other areas as well where microscopic physical details of a specimen are important. A computational procedure which enables the holographic data collected by the detector to be used to correct for misalignments introduced by inexact knowledge of the relative positions of the spherical reference scatterer and the sample under investigation has been developed. If the correction is performed prior to reconstruction, full compensation can be achieved and a faithfully reconstructed image produced. 7 figs.

  9. Apparatus for generating x-ray holograms

    DOE Patents [OSTI]

    Rhodes, Charles K. (Chicago, IL); Boyer, Keith (Los Alamos, NM); Solem, Johndale C. (Los Alamos, NM); Haddad, Waleed S. (Chicago, IL)

    1990-01-01T23:59:59.000Z

    Apparatus for x-ray microholography of living biological materials. A Fourier transform holographic configuration is described as being most suitable for the 3-dimensional recording of the physical characteristics of biological specimens. The use of a spherical scatterer as a reference and a charge-coupled device two-dimensional detector array placed in the forward direction relative to the incident x-radiation for viewing electromagnetic radiation simultaneously scattered from both the specimen and the reference scatterer permits the ready reconstruction of the details of the specimen from the fringe pattern detected by the charge-coupled device. For example, by using a nickel reference scatter at 4.5 nm, sufficient reference illumination is provided over a wide enough angle to allow similar resolution in both transverse and longitudinal directions. Both laser and synchrotron radiation sources are feasible for generating microholographs. Operation in the water window (2.4 to 4.5 nm) should provide maximum contrast for features of the specimen and spatial resolution on the order of the wavelength of x-radiation should be possible in all three dimensions, which is sufficient for the visualization of many biological features. It is anticipated that the present apparatus will find utility in other areas as well where microscopic physical details of a specimen are important. A computational procedure which enables the holographic data collected by the detector to be used to correct for misalignments introduced by inexact knowledge of the relative positions of the spherical reference scatterer and the sample under investigation has been developed. If the correction is performed prior to reconstruction, full compensation can be achieved and a faithfully reconstructed image produced.

  10. The Coherent X-ray Imaging (CXI) Instrument at the Linac Coherent Light Source (LCLS)

    SciTech Connect (OSTI)

    Boutet, Sebastien; Williams, Garth J.; /SLAC; ,

    2011-08-16T23:59:59.000Z

    The Linac Coherent Light Source (LCLS) has become the first ever operational hard X-ray Free Electron Laser in 2009. It will operate as a user facility capable of delivering unique research opportunities in multiple fields of science. The LCLS and the LCLS Ultrafast Science Instruments (LUSI) construction projects are developing instruments designed to make full use of the capabilities afforded by the LCLS beam. One such instrument is being designed to utilize the LCLS coherent beam to image with high resolution any sub-micron object. This instrument is called the Coherent X-ray Imaging (CXI) instrument. This instrument will provide a flexible optical system capable of tailoring key beam parameters for the users. A suite of shot-to-shot diagnostics will also be provided to characterize the beam on every pulse. The provided instrumentation will include multi-purpose sample environments, sample delivery and a custom detector capable of collecting 2D data at 120 Hz. In this article, the LCLS will be briefly introduced along with the technique of Coherent X-ray Diffractive Imaging (CXDI). A few examples of scientific opportunities using the CXI instrument will be described. Finally, the conceptual layout of the instrument will be presented along with a description of the key requirements for the overall system and specific devices required.

  11. Spatiotemporal focusing dynamics in plasmas at X-ray wavelength

    SciTech Connect (OSTI)

    Sharma, A., E-mail: a-physics2001@yahoo.com; Tibai, Z. [Institute of Physics, University of Pecs, Pecs–7624 (Hungary)] [Institute of Physics, University of Pecs, Pecs–7624 (Hungary); Hebling, J. [Institute of Physics, University of Pecs, Pecs–7624 (Hungary) [Institute of Physics, University of Pecs, Pecs–7624 (Hungary); Szentagothai Research Centre, University of Pecs, Pecs-7624 (Hungary); Mishra, S. K. [Institute for Plasma Research, Gandhinagar (India)] [Institute for Plasma Research, Gandhinagar (India)

    2014-03-15T23:59:59.000Z

    Using a finite curvature beam, we investigate here the spatiotemporal focusing dynamics of a laser pulse in plasmas at X-ray wavelength. We trace the dependence of curvature parameter on the focusing of laser pulse and recognize that the self-focusing in plasma is more intense for the X-ray laser pulse with curved wavefront than with flat wavefront. The simulation results demonstrate that spatiotemporal focusing dynamics in plasmas can be controlled with the appropriate choice of beam-plasma parameters to explore the high intensity effects in X-ray regime.

  12. X-ray backscatter imaging of nuclear materials

    DOE Patents [OSTI]

    Chapman, Jeffrey Allen; Gunning, John E; Hollenbach, Daniel F; Ott, Larry J; Shedlock, Daniel

    2014-09-30T23:59:59.000Z

    The energy of an X-ray beam and critical depth are selected to detect structural discontinuities in a material having an atomic number Z of 57 or greater. The critical depth is selected by adjusting the geometry of a collimator that blocks backscattered radiation so that backscattered X-ray originating from a depth less than the critical depth is not detected. Structures of Lanthanides and Actinides, including nuclear fuel rod materials, can be inspected for structural discontinuities such as gaps, cracks, and chipping employing the backscattered X-ray.

  13. Gated x-ray detector for the National Ignition Facility

    SciTech Connect (OSTI)

    Oertel, John A.; Aragonez, Robert; Archuleta, Tom; Barnes, Cris; Casper, Larry; Fatherley, Valerie; Heinrichs, Todd; King, Robert; Landers, Doug; Lopez, Frank; Sanchez, Phillip; Sandoval, George; Schrank, Lou; Walsh, Peter; Bell, Perry; Brown, Matt; Costa, Robert; Holder, Joe; Montelongo, Sam; Pederson, Neal [Los Alamos National Laboratory, Los Alamos, New Mexico 87544 (United States); Lawrence Livermore National Laboratory, Livermore, California 94551-0808 (United States); VI Control Systems Ltd., Los Alamos, New Mexico 87544 (United States)

    2006-10-15T23:59:59.000Z

    Two new gated x-ray imaging cameras have recently been designed, constructed, and delivered to the National Ignition Facility in Livermore, CA. These gated x-Ray detectors are each designed to fit within an aluminum airbox with a large capacity cooling plane and are fitted with an array of environmental housekeeping sensors. These instruments are significantly different from earlier generations of gated x-ray images due, in part, to an innovative impedance matching scheme, advanced phosphor screens, pulsed phosphor circuits, precision assembly fixturing, unique system monitoring, and complete remote computer control. Preliminary characterization has shown repeatable uniformity between imaging strips, improved spatial resolution, and no detectable impedance reflections.

  14. X-ray afterglows from gamma-ray bursts

    E-Print Network [OSTI]

    M. Tavani

    1997-03-24T23:59:59.000Z

    We consider possible interpretations of the recently detected X- ray afterglow from the gamma-ray burst source GRB 970228. Cosmological and Galactic models of gamma-ray bursts predict different flux and spectral evolution of X-ray afterglows. We show that models based on adiabatic expansion of relativistic forward shocks require very efficient particle energization or post-burst re-acceleration during the expansion. Cooling neutron star models predict a very distinctive spectral and flux evolution that can be tested in current X-ray data.

  15. Linear accelerator x-ray sources with high duty cycle

    SciTech Connect (OSTI)

    Condron, Cathie; Brown, Craig; Gozani, Tsahi; Langeveld, Willem G. J. [Rapiscan Laboratories, Inc., 520 Almanor Ave. Sunnyvale, CA 94085 (United States); Hernandez, Michael [XScell corp., 2134 Old Middlefield Way, Mountain View, CA 94043 (United States)

    2013-04-19T23:59:59.000Z

    X-ray cargo inspection systems typically use a several-MV pulsed linear accelerator (linac) to produce a bremsstrahlung spectrum of x rays by bombarding a target with electrons. The x rays traverse the cargo and are detected by a detector array. Spectroscopy of the detected x rays is very desirable: if one can determine the spectrum of the transmitted x rays, one can determine the Z of the material they traversed. Even in relatively low-dose modes of operation, thousands of x rays arrive at each detector element during each pulse, unless the x rays are heavily absorbed or scattered by the cargo. For portal or fixed-site systems, dose rates, and therefore x-ray count rates, are even higher. Because of the high x-ray count rate, spectroscopy is impractical in conventional cargo inspection systems, except in certain special cases. For a mobile system, typical pulse durations are a few microseconds, and the number of pulses is on the order of 100 per second, leading to a duty factor of about 0.04%. Clearly, a linear accelerator x-ray source with much higher duty factor would be useful, since then the same number of x rays could be spread out over time, reducing the x-ray count rate. In this paper, we explore the possibility of designing a linear accelerator system, using more or less Conventional Off the Shelf (COTS) components, capable of duty cycles of 1% or greater. A survey was conducted of available linac RF source options and, given the possibilities, calculations were performed for suitable beam centerline designs. Keeping in mind that the size and cost of the accelerator system should be practical for use in a mobile cargo inspection system, only a few options are shown to be reasonably feasible, both requiring the use of klystrons instead of the magnetrons used in conventional systems. An S-Band design appears clearly possible, and there is also a promising X-Band design.

  16. Characterization of X-ray generator beam profiles.

    SciTech Connect (OSTI)

    Mitchell, Dean J; Harding, Lee T.; Thoreson, Gregory G.; Theisen, Lisa Anne; Parmeter, John Ethan; Thompson, Kyle Richard

    2013-07-01T23:59:59.000Z

    T to compute the radiography properties of various materials, the flux profiles of X-ray sources must be characterized. This report describes the characterization of X-ray beam profiles from a Kimtron industrial 450 kVp radiography system with a Comet MXC-45 HP/11 bipolar oil-cooled X-ray tube. The empirical method described here uses a detector response function to derive photon flux profiles based on data collected with a small cadmium telluride detector. The flux profiles are then reduced to a simple parametric form that enables computation of beam profiles for arbitrary accelerator energies.

  17. Automated suppression of errors in LTP-II slope measurements with x-ray optics

    E-Print Network [OSTI]

    Ali, Zulfiqar

    2011-01-01T23:59:59.000Z

    slope measurements with x-ray optics Zulfiqar Ali, Curtis L.with state-of-the-art x-ray optics. Significant suppressionscanning, metrology of x-ray optics, deflectometry Abstract

  18. X-ray optics metrology limited by random noise, instrumental drifts, and systematic errors

    E-Print Network [OSTI]

    Yashchuk, Valeriy V.

    2010-01-01T23:59:59.000Z

    X-ray optics metrology limited by random noise, instrumentalUSA Center for X-ray Optics, Lawrence Berkeley Nationaland reflecting x-ray optics suitable for micro- and nano-

  19. atf compton x-ray: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    D; Fritzsche, S 2014-01-01 14 Photospheres, Comptonization and X-ray Lines in Gamma Ray Bursts Astrophysics (arXiv) Summary: Steep X-ray spectral slopes, X-ray excesses and...

  20. adc x-ray binary: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    systems. Sudip Bhattacharyya 2010-02-24 17 X-ray Transients from X-ray Binaries to Gamma Ray Bursts CERN Preprints Summary: We discuss three classes of x-ray transients to...

  1. Radiation exposure in X-ray-based imaging techniques used in osteoporosis

    E-Print Network [OSTI]

    Damilakis, John; Adams, Judith E.; Guglielmi, Giuseppe; Link, Thomas M.

    2010-01-01T23:59:59.000Z

    and nonradiologists in dual-energy X-ray absorptiometrymorphometry studies using dual-energy X-ray absorptiometry.dose measurements in dual energy X-ray absorptiometry (DXA).

  2. Beyond 3-D X-ray Imaging: Methodology Development and Applications...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    to the availability of the new generation of X-ray sources and the advanced X-ray optics. The advanced X-ray Optics along with novel methodology has made it possible to...

  3. How Can X-ray Transient Absorption Spectroscopy Aide Solar Energy...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    are from optimized on structural, energetic and dynamic parameters. Intense X-ray pulses from synchrotrons and X-ray free electrons lasers coupled with ultrafast lasers...

  4. X-rays only when you want them: Report on Pseudo-single-bunch...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Speaker: David Robin, Lawrence Berkeley National Laboratory Program Description Laser pump - x-ray probe experiments require control over the x-ray pulse pattern and timing. Such...

  5. Scanning X-ray Microscopy Investigations into the Electron Beam Exposure Mechanism of Hydrogen Silsesquioxane Resists

    E-Print Network [OSTI]

    Olynick, Deirdre L.; Tivanski, Alexei V.; Gilles, Mary K.; Tyliszczak, Tolek; Salmassi, Farhad; Liddle, J. Alexander

    2006-01-01T23:59:59.000Z

    Scanning X-ray Microscopy Investigations into the Electronchemistry is investigated by Scanning Transmission X-raythe area exposed. 15 Recently, scanning transmission x-ray

  6. Soft X-Ray Microscopy and Spectroscopy at the Molecular Environmental...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Soft X-Ray Microscopy and Spectroscopy at the Molecular Environmental Science Beamline at the Advanced Light Source. Soft X-Ray Microscopy and Spectroscopy at the Molecular...

  7. X-Ray Fluorescence (XRF) Analysis of Obsidian Artifacts from Shoofly Ruin, Central Arizona

    E-Print Network [OSTI]

    Shackley, M. Steven

    1986-01-01T23:59:59.000Z

    X-RAY FLUORESCENCE (XRF) ANALYSIS OF OBSIDIAN ARTIFACTS FROM62:426-437. SOUTHWEST XRF PAPER Table 1. X-ray fluorescence

  8. Using Light to Control How X Rays Interact with Matter

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Using Light to Control How X Rays Interact with Matter Print Schemes that use one light pulse to manipulate interactions of another with matter are well developed in the...

  9. In situ X-ray Characterization of Energy Storage Materials |...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    X-ray Characterization of Energy Storage Materials Tuesday, July 9, 2013 - 11:00am SLAC, Conference Room 137-322 Presented by Johanna Nelson, Stanford Postdoctoral Scholar, SSRL...

  10. Streaked x-ray microscopy of laser-fusion targets

    SciTech Connect (OSTI)

    Price, R.H.; Campbell, E.M.; Rosen, M.D.; Auerbach, J.M.; Phillion, D.W.; Whitlock, R.R.; Obenshain, S.P.; McLean, E.A.; Ripin, B.H.

    1982-08-01T23:59:59.000Z

    An ultrafast soft x-ray streak camera has been coupled to a Wolter axisymmetric x-ray microscope. This system was used to observe the dynamics of laser fusion targets both in self emission and backlit by laser produced x-ray sources. Spatial resolution was 7 ..mu..m and temporal resolution was 20 ps. Data is presented showing the ablative acceleration of foils to velocities near 10/sup 7/ cm/sec and the collision of an accelerated foil with a second foil, observed using 3 keV streaked x-ray backlighting. Good agreement was found between hydrocode simulations, simple models of the ablative acceleration and the observed velocities of the carbon foils.

  11. Resonant Soft X-Ray Scattering - Combining Structural with Spectroscop...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    as well as important L-edges of the 3d transition metals important in magnetic and oxide systems. Measurements of soft x-ray absorption spectra are inherently surface sensitive,...

  12. Staff at sector 30, inelastic x-ray scattering

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Sector 30 Staff Advanced Photon Source A U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences national synchrotron x-ray research facility Search Button...

  13. Imaging Quantum States with X-ray Compton Scattering | Stanford...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Imaging Quantum States with X-ray Compton Scattering Wednesday, April 8, 2015 - 3:00pm SLAC, Redtail Hawk Conference Room 108A Speaker: Yoshiharu Sakurai (Japan Synchrotron...

  14. The Identification Problem for the attenuated X-ray transform

    E-Print Network [OSTI]

    2013-11-16T23:59:59.000Z

    X-ray transform has been solved in [27], see also [15]. The main result in .... For any compact set K ? T2, we define Hs(K) to be the closed subspace of Hs(T2) of

  15. Systems and methods for detecting x-rays

    DOE Patents [OSTI]

    Bross, Alan D.; Mellott, Kerry L.; Pla-Dalmau, Anna

    2006-05-02T23:59:59.000Z

    Systems and methods for detecting x-rays are disclosed herein. One or more x-ray-sensitive scintillators can be configured from a plurality of heavy element nano-sized particles and a plastic material, such as polystyrene. As will be explained in greater detail herein, the heavy element nano-sized particles (e.g., PbWO4) can be compounded into the plastic material with at least one dopant that permits the plastic material to scintillate. X-rays interact with the heavy element nano-sized particles to produce electrons that can deposit energy in the x-ray sensitive scintillator, which in turn can produce light.

  16. Epoxy replication for Wolter x-ray microscope fabrication

    SciTech Connect (OSTI)

    Priedhorsky, W.

    1981-01-01T23:59:59.000Z

    An epoxy replica of a test piece designed to simulate a Wolter x-ray microscope geometry showed no loss of x-ray reflectivity or resolution, compared to the original. The test piece was a diamond-turned cone with 1.5/sup 0/ half angle. A flat was fly-cut on one side, then super- and conventionally polished. The replica was separated at the 1.5/sup 0/-draft angle, simulating a shallow angle Wolter microscope geometry. A test with 8.34 A x rays at 0.9/sup 0/ grazing angle showed a reflectivity of 67% for the replica flat surface, and 70% for the original. No spread of the reflected beam was observed with a 20-arc second wide test beam. This test verifies the epoxy replication technique for production of Wolter x-ray microscopes.

  17. X-ray ptychography, fluorescence microscopy combo sheds new light...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    advance required the high brightness of the APS as an X-ray source and points the way to advances that can be expected as it is planned to be increased a hundredfold in the...

  18. Vitreous carbon mask substrate for X-ray lithography

    DOE Patents [OSTI]

    Aigeldinger, Georg (Livermore, CA); Skala, Dawn M. (Fremont, CA); Griffiths, Stewart K. (Livermore, CA); Talin, Albert Alec (Livermore, CA); Losey, Matthew W. (Livermore, CA); Yang, Chu-Yeu Peter (Dublin, CA)

    2009-10-27T23:59:59.000Z

    The present invention is directed to the use of vitreous carbon as a substrate material for providing masks for X-ray lithography. The new substrate also enables a small thickness of the mask absorber used to pattern the resist, and this enables improved mask accuracy. An alternative embodiment comprised the use of vitreous carbon as a LIGA substrate wherein the VC wafer blank is etched in a reactive ion plasma after which an X-ray resist is bonded. This surface treatment provides a surface enabling good adhesion of the X-ray photoresist and subsequent nucleation and adhesion of the electrodeposited metal for LIGA mold-making while the VC substrate practically eliminates secondary radiation effects that lead to delamination of the X-ray resist form the substrate, the loss of isolated resist features, and the formation of a resist layer adjacent to the substrate that is insoluble in the developer.

  19. Performance enhancement approaches for a dual energy x-ray

    E-Print Network [OSTI]

    Fu, Kenneth

    2010-01-01T23:59:59.000Z

    Evans, J.P.O. , “Stereoscopic dual energy imaging for targetCrawford, C.R. , “Dual Energy Volumetric X-ray Tomographicimages in 4–10 MeV Dual- energy customs system for material

  20. Magnetism studies using resonant, coherent, x-ray scattering...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Magnetism studies using resonant, coherent, x-ray scattering Monday, September 10, 2012 - 10:00am SLAC, Bldg. 137, Room 226 Keoki Seu Seminar: With the advent of free electron...

  1. Towards attosecond X-ray pulses from the FEL

    E-Print Network [OSTI]

    Zholents, Alexander A.; Fawley, William M.

    2004-01-01T23:59:59.000Z

    can be used instead of HC FEL. In the following illustra-UM is now tuned for resonant FEL interaction with the 32-nmAttosecond X-Ray Pulses from the FEL Alexander A. Zholents,

  2. X-ray micromodulated luminescence tomography in dual-cone ...

    E-Print Network [OSTI]

    2014-07-01T23:59:59.000Z

    Jul 16, 2014 ... ing the intensity of x-ray energy at the vertex point of a double- cone beam. ... such focusing element, but it is of low efficiency and restricted.

  3. X-ray mask and method for making

    DOE Patents [OSTI]

    Morales, Alfredo M.

    2004-10-26T23:59:59.000Z

    The present invention describes a method for fabricating an x-ray mask tool which is a contact lithographic mask which can provide an x-ray exposure dose which is adjustable from point-to-point. The tool is useful in the preparation of LIGA plating molds made from PMMA, or similar materials. In particular the tool is useful for providing an ability to apply a graded, or "stepped" x-ray exposure dose across a photosensitive substrate. By controlling the x-ray radiation dose from point-to-point, it is possible to control the development process for removing exposed portions of the substrate; adjusting it such that each of these portions develops at a more or less uniformly rate regardless of feature size or feature density distribution.

  4. High performance x-ray anti-scatter grid

    DOE Patents [OSTI]

    Logan, C.M.

    1995-05-23T23:59:59.000Z

    Disclosed are an x-ray anti-scatter grid for x-ray imaging, particularly for screening mammography, and method for fabricating same, x-rays incident along a direct path pass through a grid composed of a plurality of parallel or crossed openings, microchannels, grooves, or slots etched in a substrate, such as silicon, having the walls of the microchannels or slots coated with a high opacity material, such as gold, while x-rays incident at angels with respect to the slots of the grid, arising from scatter, are blocked. The thickness of the substrate is dependent on the specific application of the grid, whereby a substrate of the grid for mammography would be thinner than one for chest radiology. Instead of coating the walls of the slots, such could be filed with an appropriate liquid, such as mercury. 4 Figs.

  5. High performance x-ray anti-scatter grid

    DOE Patents [OSTI]

    Logan, Clinton M. (Pleasanton, CA)

    1995-01-01T23:59:59.000Z

    An x-ray anti-scatter grid for x-ray imaging, particularly for screening mammography, and method for fabricating same, x-rays incident along a direct path pass through a grid composed of a plurality of parallel or crossed openings, microchannels, grooves, or slots etched in a substrate, such as silicon, having the walls of the microchannels or slots coated with a high opacity material, such as gold, while x-rays incident at angels with respect to the slots of the grid, arising from scatter, are blocked. The thickness of the substrate is dependent on the specific application of the grid, whereby a substrate of the grid for mammography would be thinner than one for chest radiology. Instead of coating the walls of the slots, such could be filed with an appropriate liquid, such as mercury.

  6. angle diffraction studies: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    A. 3 DMSO-Induced Dehydration of DPPC Membranes Studied by X-ray Diffraction, Small-Angle Neutron Scattering, and Calorimetry Condensed Matter (arXiv) Summary: The influence of...

  7. Recent Flash X-Ray Injector Modeling

    SciTech Connect (OSTI)

    Houck, T; Blackfield, D; Burke, J; Chen, Y; Javedani, J; Paul, A C

    2004-11-10T23:59:59.000Z

    The injector of the Flash X-Ray (FXR) accelerator has a significantly larger than expected beam emittance. A computer modeling effort involving three different injector design codes was undertaken to characterize the FXR injector and determine the cause of the large emittance. There were some variations between the codes, but in general the simulations were consistent and pointed towards a much smaller normalized, rms emittance (36 cm-mr) than what was measured (193 cm-mr) at the exit of the injector using a pepperpot technique. The simulations also indicated that the present diode design was robust with respect to perturbations to the nominal design. Easily detected mechanical alignment/position errors and magnet errors did not lead to appreciable increase in the simulated emittance. The physics of electron emission was not modeled by any of the codes and could be the source of increased emittance. The nominal simulation assumed uniform Child-Langmuir Law emission from the velvet cathode and no shroud emission. Simulations that looked at extreme non-uniform cathode and shroud emission scenarios resulted in doubling of the emittance. An alternative approach was to question the pepperpot measurement. Simulations of the measurement showed that the pepperpot aperture foil could double the emittance with respect to the non-disturbed beam. This leads to a diplomatic explanation of the discrepancy between predicted and measured emittance where the fault is shared. The measured value is too high due to the effect of the diagnostic on the beam and the simulations are too low because of unaccounted cathode and/or shroud emission physics. Fortunately there is a relatively simple experiment that can resolve the emittance discrepancy. If the large measured emittance value is correct, the beam envelope is emittance dominated at modest values of focusing field and beam radius. Measurements of the beam envelope on an imaging foil at the exit of the injector would lead to an accurate value of the emittance. If the emittance was approximately half of the measured value, the beam envelope is slightly space charge dominated, but envelope measurements would set reasonable bounds on the emittance value. For an emittance much less than 100 cm-mr, the envelope measurements would be insensitive to emittance. The outcome of this envelope experiment determines if a redesigned diode is needed or if more sophisticated emittance measurements should be pursued.

  8. X-ray tube with magnetic electron steering

    DOE Patents [OSTI]

    Reed, Kim W. (Albuquerque, NM); Turman, Bobby N. (Albuquerque, NM); Kaye, Ronald J. (Albuquerque, NM); Schneider, Larry X. (Albuquerque, NM)

    2000-01-01T23:59:59.000Z

    An X-ray tube uses a magnetic field to steer electrons. The magnetic field urges electrons toward the anode, increasing the proportion of electrons emitted from the cathode that reach desired portions of the anode and consequently contribute to X-ray production. The magnetic field also urges electrons reflected from the anode back to the anode, further increasing the efficiency of the tube.

  9. Quantum coherence phenomena in x-ray optics

    E-Print Network [OSTI]

    Anisimov, Petr Mikhailovich

    2009-05-15T23:59:59.000Z

    QUANTUM COHERENCE PHENOMENA IN X-RAY OPTICS A Dissertation by PETR MIKHAILOVICH ANISIMOV Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY December... 2008 Major Subject: Physics QUANTUM COHERENCE PHENOMENA IN X-RAY OPTICS A Dissertation by PETR MIKHAILOVICH ANISIMOV Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree of DOCTOR...

  10. New Directions in X-Ray Light Sources

    ScienceCinema (OSTI)

    Roger Falcone

    2010-01-08T23:59:59.000Z

    July 15, 2008 Berkeley Lab lecture: Molecular movies of chemical reactions and material phase transformations need a strobe of x-rays, the penetrating light that reveals how atoms and molecules assemble in chemical and biological systems and complex materials. Roger Falcone, Director of the Advanced Light Source,will discuss a new generation of x ray sources that will enable a new science of atomic dynamics on ultrafast timescales.

  11. Enhanced betatron X-rays from axially modulated plasma wakefields

    E-Print Network [OSTI]

    Palastro, J P; Gordon, D

    2015-01-01T23:59:59.000Z

    In the cavitation regime of plasma-based accelerators, a population of high-energy electrons tailing the driver can undergo betatron motion. The motion results in X-ray emission, but the brilliance and photon energy are limited by the electrons' initial transverse coordinate. To overcome this, we exploit parametrically unstable betatron motion in a cavitated, axially modulated plasma. Theory and simulations are presented showing that the unstable oscillations increase both the total X-ray energy and average photon energy.

  12. A short working distance multiple crystal x-ray spectrometer

    SciTech Connect (OSTI)

    Dickinson, B.; Seidler, G. T.; Webb, Z. W.; Bradley, J. A.; Nagle, K. P. [Department of Physics, University of Washington, Seattle, Washington 98195 (United States); Heald, S. M. [Advanced Photon Source, Argonne National Laboratories, Argonne, Illinois 60439 (United States); Gordon, R. A. [Department of Physics, Simon Fraser University, Burnaby, British Columbia V5A 1S6 (Canada); Chou, I. M. [U.S. Geological Survey, Reston, Virginia 20192 (United States)

    2008-12-15T23:59:59.000Z

    For x-ray spot sizes of a few tens of microns or smaller, a millimeter-sized flat analyzer crystal placed {approx}1 cm from the sample will exhibit high energy resolution while subtending a collection solid angle comparable to that of a typical spherically bent crystal analyzer (SBCA) at much larger working distances. Based on this observation and a nonfocusing geometry for the analyzer optic, we have constructed and tested a short working distance (SWD) multicrystal x-ray spectrometer. This prototype instrument has a maximum effective collection solid angle of 0.14 sr, comparable to that of 17 SBCA at 1 m working distance. We find good agreement with prior work for measurements of the Mn K{beta} x-ray emission and resonant inelastic x-ray scattering for MnO, and also for measurements of the x-ray absorption near-edge structure for Dy metal using L{alpha}{sub 2} partial-fluorescence yield detection. We discuss future applications at third- and fourth-generation light sources. For concentrated samples, the extremely large collection angle of SWD spectrometers will permit collection of high-resolution x-ray emission spectra with a single pulse of the Linac Coherent Light Source. The range of applications of SWD spectrometers and traditional multi-SBCA instruments has some overlap, but also is significantly complementary.

  13. Quiet Sun X-rays as Signature for New Particles

    E-Print Network [OSTI]

    K. Zioutas; K. Dennerl; L. DiLella; D. H. H. Hoffmann; J. Jacoby; Th. Papaevangelou

    2004-03-08T23:59:59.000Z

    We have studied published data from the Yohkoh solar X-ray mission, with the purpose of searching for signals from radiative decays of new, as yet undiscovered massive neutral particles. This search is based on the prediction that solar axions of the Kaluza-Klein type should result in the emission of X-rays from the Sun direction beyond the limb with a characteristic radial distribution. These X-rays should be observed more easily during periods of quiet Sun. An additional signature is the observed emission of hard X-rays by SMM, NEAR and RHESSI. The recent observation made by RHESSI of a continuous emission from the non-flaring Sun of X-rays in the 3 to ~15 keV range fits the generic axion scenario. This work also suggests new analyses of existing data, in order to exclude instrumental effects; it provides the rationale for targeted observations with present and upcoming (solar) X-ray telescopes, which can provide the final answer on the nature of the signals considered here. Such measurements become more promising during the forthcoming solar cycle minimum with an increased number of quiet Sun periods.

  14. X-ray absorption in distant type II QSOs

    E-Print Network [OSTI]

    Krumpe, M; Corral, A; Schwope, A D; Carrera, F J; Barcons, X; Page, M; Mateos, S; Tedds, J A; Watson, M G

    2008-01-01T23:59:59.000Z

    We present the results of the X-ray spectral analysis of an XMM-Newton-selected type II QSO sample with z>0.5 and 0.5-10 keV flux of 0.3-33 x 10^{-14} erg/s/cm^2. The distribution of absorbing column densities in type II QSOs is investigated and the dependence of absorption on X-ray luminosity and redshift is studied. We inspected 51 spectroscopically classified type II QSO candidates from the XMM-Newton Marano field survey, the XMM-Newton-2dF wide angle survey (XWAS), and the AXIS survey to set-up a well-defined sample with secure optical type II identifications. Fourteen type II QSOs were classified and an X-ray spectral analysis performed. Since most of our sources have only ~40 X-ray counts (PN-detector), we carefully studied the fit results of the simulated X-ray spectra as a function of fit statistic and binning method. We determined that fitting the spectra with the Cash-statistic and a binning of minimum one count per bin recovers the input values of the simulated X-ray spectra best. Above 100 PN coun...

  15. Spectral Formation in X-Ray Pulsar Accretion Columns

    E-Print Network [OSTI]

    Peter A. Becker; Michael T. Wolff

    2005-03-03T23:59:59.000Z

    We present the first self-consistent model for the dynamics and the radiative transfer occurring in bright X-ray pulsar accretion columns, with a special focus on the role of the shock in energizing the emerging X-rays. The pressure inside the accretion column of a luminous X-ray pulsar is dominated by the photons, and consequently the equations describing the coupled radiative-dynamical structure must be solved simultaneously. Spectral formation in these sources is therefore a complex, nonlinear phenomenon. We obtain the analytical solution for the Green's function describing the upscattering of monochromatic radiation injected into the column from the thermal mound located near the base of the flow. The Green's function is convolved with a Planck distribution to model the X-ray spectrum resulting from the reprocessing of blackbody photons produced in the thermal mound. These photons diffuse through the infalling gas and eventually escape out the walls of the column, forming the observed X-ray spectrum. We show that the resulting column-integrated, phase-averaged spectrum has a power-law shape at high energies and a blackbody shape at low energies, in agreement with the observational data for many X-ray pulsars.

  16. The color of X-rays Spectral X-ray computed tomography using energy sensitive pixel detectors

    E-Print Network [OSTI]

    Schioppa, Enrico Junior

    Energy sensitive X-ray imaging detectors are produced by connecting a semiconductor sensor to a spectroscopic pixel readout chip. In this thesis, the applicability of such detectors to X-ray Computed Tomography (CT) is studied. A prototype Medipix based silicon detector is calibrated using X-ray fluorescence. The charge transport properties of the sensor are characterized using a high energy beam of charged particles at the Super Proton Synchrotron (SPS) at the European Center for Nuclear Research (CERN). Monochromatic X-rays at the European Synchrotron Radiation Facility (ESRF) are used to determined the energy response function. These data are used to implement a physics-based CT projection operator that accounts for the transmission of the source spectrum through the sample and detector effects. Based on this projection operator, an iterative spectral CT reconstruction algorithm is developed by extending an Ordered Subset Expectation Maximization (OSEM) method. Subsequently, a maximum likelihood based algo...

  17. 54X-rays from Hot Gases Near the SN1979C Black Hole The Chandra X-Ray Observatory

    E-Print Network [OSTI]

    is in solar mass units, and R is in kilometers. Problem 1 - Combining these equations using the method-Newton and the German ROSAT observatory revealed a bright source of X-rays that has remained steady for the 12 years, or distribution of X-rays with energy, support the idea that the object in SN 1979C is a black hole being fed

  18. X-ray absorption in distant type II QSOs

    E-Print Network [OSTI]

    M. Krumpe; G. Lamer; A. Corral; A. D. Schwope; F. J. Carrera; X. Barcons; M. Page; S. Mateos; J. A. Tedds; M. G. Watson

    2008-03-10T23:59:59.000Z

    We present the results of the X-ray spectral analysis of an XMM-Newton-selected type II QSO sample with z>0.5 and 0.5-10 keV flux of 0.3-33 x 10^{-14} erg/s/cm^2. The distribution of absorbing column densities in type II QSOs is investigated and the dependence of absorption on X-ray luminosity and redshift is studied. We inspected 51 spectroscopically classified type II QSO candidates from the XMM-Newton Marano field survey, the XMM-Newton-2dF wide angle survey (XWAS), and the AXIS survey to set-up a well-defined sample with secure optical type II identifications. Fourteen type II QSOs were classified and an X-ray spectral analysis performed. Since most of our sources have only ~40 X-ray counts (PN-detector), we carefully studied the fit results of the simulated X-ray spectra as a function of fit statistic and binning method. We determined that fitting the spectra with the Cash-statistic and a binning of minimum one count per bin recovers the input values of the simulated X-ray spectra best. Above 100 PN counts, the free fits of the spectrum's slope and absorbing hydrogen column density are reliable. We find only moderate absorption (N_H=(2-10) x 10^22 cm^-2) and no obvious trends with redshift and intrinsic X-ray luminosity. In a few cases a Compton-thick absorber cannot be excluded. Two type II objects with no X-ray absorption were discovered. We find no evidence for an intrinsic separation between type II AGN and high X-ray luminosity type II QSO in terms of absorption. The stacked X-ray spectrum of our 14 type II QSOs shows no iron K-alpha line. In contrast, the stack of the 8 type II AGN reveals a very prominent iron K-alpha line at an energy of ~ 6.6 keV and an EW ~ 2 keV.

  19. A High Efficiency Grazing Incidence Pumped X-ray Laser

    SciTech Connect (OSTI)

    Dunn, J; Keenan, R; Price, D F; Patel, P K; Smith, R F; Shlyaptsev, V N

    2006-08-31T23:59:59.000Z

    The main objective of the project is to demonstrate a proof-of-principle, new type of high efficiency, short wavelength x-ray laser source that will operate at unprecedented high repetition rates (10Hz) that could be scaled to 1kHz or higher. The development of a high average power, tabletop x-ray laser would serve to complement the wavelength range of 3rd and future 4th generation light sources, e.g. the LCLS, being developed by DOE-Basic Energy Sciences. The latter are large, expensive, central, synchrotron-based facilities while the tabletop x-ray laser is compact, high-power laser-driven, and relatively inexpensive. The demonstration of such a unique, ultra-fast source would allow us to attract funding from DOE-BES, NSF and other agencies to pursue probing of diverse materials undergoing ultrafast changes. Secondly, this capability would have a profound impact on the semiconductor industry since a coherent x-ray laser source would be ideal for ''at wavelength'' {approx}13 nm metrology and microscopy of optics and masks used in EUV lithography. The project has major technical challenges. We will perform grazing-incidence pumped laser-plasma experiments in flat or groove targets which are required to improve the pumping efficiency by ten times. Plasma density characterization using our existing unique picosecond x-ray laser interferometry of laser-irradiated targets is necessary. Simulations of optical laser propagation as well as x-ray laser production and propagation through freely expanding and confined plasma geometries are essential. The research would be conducted using the Physics Directorate Callisto and COMET high power lasers. At the end of the project, we expect to have a high-efficiency x-ray laser scheme operating below 20 nm at 10Hz with a pulse duration of {approx}2 ps. This will represent the state-of-the-art in x-ray lasers and would be a major step forward from our present picosecond laser-driven x-ray lasers. There is an added bonus of creating the shortest wavelength laboratory x-ray laser, below 4.5 nm and operating in the water window, by using the high-energy capability of the Titan laser.

  20. HIgh Rate X-ray Fluorescence Detector

    SciTech Connect (OSTI)

    Grudberg, Peter Matthew [XIA LLC

    2013-04-30T23:59:59.000Z

    The purpose of this project was to develop a compact, modular multi-channel x-ray detector with integrated electronics. This detector, based upon emerging silicon drift detector (SDD) technology, will be capable of high data rate operation superior to the current state of the art offered by high purity germanium (HPGe) detectors, without the need for liquid nitrogen. In addition, by integrating the processing electronics inside the detector housing, the detector performance will be much less affected by the typically noisy electrical environment of a synchrotron hutch, and will also be much more compact than current systems, which can include a detector involving a large LN2 dewar and multiple racks of electronics. The combined detector/processor system is designed to match or exceed the performance and features of currently available detector systems, at a lower cost and with more ease of use due to the small size of the detector. In addition, the detector system is designed to be modular, so a small system might just have one detector module, while a larger system can have many â?? you can start with one detector module, and add more as needs grow and budget allows. The modular nature also serves to simplify repair. In large part, we were successful in achieving our goals. We did develop a very high performance, large area multi-channel SDD detector, packaged with all associated electronics, which is easy to use and requires minimal external support (a simple power supply module and a closed-loop water cooling system). However, we did fall short of some of our stated goals. We had intended to base the detector on modular, large-area detectors from Ketek GmbH in Munich, Germany; however, these were not available in a suitable time frame for this project, so we worked instead with pnDetector GmbH (also located in Munich). They were able to provide a front-end detector module with six 100 m^2 SDD detectors (two monolithic arrays of three elements each) along with associated preamplifiers; these detectors surpassed the performance we expected to get from the Ketek detectors, however they are housed in a sealed module, which does not offer the ease of repair and expandability weâ??d hoped to achieve with the Ketek SDDâ??s. Our packaging efforts were quite successful, as we came up with a very compact way to mount the detector and to house the associated electronics, as well as a very effective way to reliably take out the heat (from the electronics as well as the detectorâ??s Peltier coolers) without risk of condensation and without external airflow or vibration, which could create problems for the target applications. While we were able to design compact processing electronics that fit into the detector assembly, they are still at the prototype stage, and would require a significant redesign to achieve product status. We have not yet tested this detector at a synchrotron facility; we do still plan on working with some close contacts at the nearby Stanford Synchrotron Radiation Laboratory (SSRL) to get some testing with the beam (using existing commercial electronics for readout, as the integrated processor is not ready for use).