The magnetic order of GdMn{sub 2}Ge{sub 2} studied by neutron diffraction and x-ray resonant magnetic scattering

Energy Technology Data Exchange (ETDEWEB)

Granovsky, S A [M V Lomonosov Moscow State University, 119991 GSP-1 Moscow (Russian Federation); Kreyssig, A; Canfield, P C [Ames Laboratory USDOE, Iowa State University, Ames, IA 50011 (United States); Doerr, M; Loewenhaupt, M [TU Dresden, Institut fuer Festkoerperphysik, D-01062, Dresden (Germany); Ritter, C [Institut Laue-Langevin, F-38042 Grenoble Cedex 9 (France); Dudzik, E; Feyerherm, R, E-mail: ser@plms.r [Helmholtz-Zentrum Berlin fuer Materialien und Energie GmbH, BESSY, D-12489, Berlin (Germany)

2010-06-09

The magnetic structure of GdMn{sub 2}Ge{sub 2} (tetragonal I4/mmm) has been studied by hot neutron powder diffraction and x-ray resonant magnetic scattering techniques. These measurements, along with the results of bulk experiments, confirm the collinear ferrimagnetic structure with moment direction parallel to the c-axis below T{sub C} = 96 K and the collinear antiferromagnetic phase in the temperature region T{sub C} < T < T{sub N} = 365 K. In the antiferromagnetic phase, x-ray resonant magnetic scattering has been detected at Mn K and Gd L{sub 2} absorption edges. The Gd contribution is a result of an induced Gd 5d electron polarization caused by the antiferromagnetic order of Mn-moments.

Structural and microstructural characterization of U{sub 3}Si{sub 2} nuclear fuel using X-ray diffraction

Energy Technology Data Exchange (ETDEWEB)

Ichikawa, Rodrigo U.; Garcia, Rafael H.L.; Silva, Andre S.B. da; Saliba-Silva, Adonis M.; Lima, Nelson B.; Martinez, Luis G. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Turrillas, Xavier, E-mail: ichikawa@usp.br, E-mail: rlgarcia@ipen.br, E-mail: andre.santos.silva@usp.br, E-mail: saliba@ipen.br, E-mail: nblima@ipen.br, E-mail: lgallego@ipen.br, E-mail: xturrillas@icmab.es [Institut de Ciència de Materials de Barcelona (ICMAB/CSIC), Cerdanyola de Vallès (Spain)

2017-07-01

In this work, two uranium silicide powdered samples, containing 67% and 42 mol% of Si, were analyzed using X-ray diffraction (named as {sup 67}Si and {sup 42}Si). For structural characterization, Rietveld refinement was used to estimate cell parameters, volume fraction (weight percent) of crystalline phases and atomic positions. For the main phases, X-ray line profile analysis (XLPA) was used to estimate mean crystallite sizes and micro strains. The {sup 67}Si sample presents higher content of USi{sub 2(}tetragonal) and the {sup 42}Si sample presents higher content of U{sub 3}Si{sub 2} (tetragonal) as identified and calculated from the XRD profiles. Overall there are no appreciable structural changes and the parameters refined are in good accordance with the ones reported in the literature. Mean crystallite sizes determined by XLPA revealed small crystallites of the order of 10{sup 1} nm and low micro strain for all samples. (author)

Two-dimensional x-ray diffraction

CERN Document Server

He, Bob B

2009-01-01

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

X-ray diffraction imaging of material microstructures

KAUST Repository

Varga, Laszlo

2016-10-20

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

Study of hydrogenation of Sm{sub 2}Fe{sub 17-y}Ga{sub y} by means of X-ray diffraction

Energy Technology Data Exchange (ETDEWEB)

Teresiak, A.; Uhlemann, M.; Kubis, M.; Gebel, B.; Mattern, N.; Mueller, K.-H. [Institut fuer Festkoerper- und Werkstofforschung Dresden e.V. (Germany)

2000-06-06

The hydrogenation process of Sm{sub 2}Fe{sub 17-y}Ga{sub y}(y=0-2) was studied. X-ray investigations show a decreasing hydrogen solubility in the intermetallic alloy with increasing Ga-content from 4.0{+-}0.3 atoms per formula unit for Sm{sub 2}Fe{sub 17} to 2.85{+-}0.05 for Sm{sub 2}Fe{sub 15}Ga{sub 2}. The larger Ga atoms reduce the size of the interstitial sites and thereby the maximum hydrogen concentration is decreased. The behaviour of the lattice parameters a and c with increasing Ga content points to a changed hydrogen distribution on the interstitial sites, becoming more statistical. In situ observations by means of high temperature X-ray diffraction show that the hydrogen absorption process is diffusion controlled. The hydrogen absorption starts at an annealing temperature of 120-140 C in all cases. The solubility of hydrogen decreases with increasing temperature. The hydrogen is completely desorbed above 350 C in all cases. The absorption/desorption process is reversible between room temperature and 400 C. Annealing at temperatures above 400 C leads to the decomposition of the Sm{sub 2}Fe{sub 17} phase, indicated by emerging of {alpha}-Fe. The formation of SmH{sub x} is established at 600 C. The decomposition temperature increases with increasing Ga-content. Up to 750 C, only Sm{sub 2}Fe{sub 17} is completely decomposed. (orig.)

Time-resolved x-ray diffraction measurement of C{sub 60} under high pressure and temperature using synchrotron radiation

Energy Technology Data Exchange (ETDEWEB)

Horikawa, T [Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531 (Japan); Suito, K [Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531 (Japan); Kobayashi, M [Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531 (Japan); Onodera, A [Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531 (Japan)

2002-11-11

C{sub 60} has been studied by means of time-resolved x-ray diffraction measurements using synchrotron radiation. Diffraction patterns were recorded at intervals of 1-10 min for samples under high pressure (12.5 and 14.3 GPa) and high temperature (up to 800 deg. C) for, at the longest, 3 h. Time, pressure, and temperature dependences of the C{sub 60} structure are presented and the relevance to the hardness of materials derived from C{sub 60} is discussed.

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

Directory of Open Access Journals (Sweden)

F. H. O’Shea

2012-02-01

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

In situ x-ray reflectivity and grazing incidence x-ray diffraction study of L 1{sub 0} ordering in {sup 57}Fe/Pt multilayers

Energy Technology Data Exchange (ETDEWEB)

Raghavendra Reddy, V; Gupta, Ajay; Gome, Anil [UGC-DAE Consortium for Scientific Research, University Campus, Khandwa Road, Indore-452 017 (India); Leitenberger, Wolfram [Institute of Physics, University of Potsdam, 14469 Potsdam (Germany); Pietsch, U [Physics Department, University of Siegen, D-57068 Siegen (Germany)], E-mail: vrreddy@csr.ernet.in, E-mail: varimalla@yahoo.com

2009-05-06

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

Investigation of electronic order using resonant soft X-ray diffraction

Energy Technology Data Exchange (ETDEWEB)

Schlappa, J.

2006-12-01

The aim of this PhD work was the application of resonant soft X-ray diffraction technique for the investigation of electronic order in transition metal oxides at the TM L{sub 2,3}-edge, trying to obtain a quantitative understanding of the data. The method was first systematically explored through application to a model system in order to test the feasibility of the technique and to understand of how X-ray optical effects have to be taken into account. Two more complex systems were investigated; stripe order in La{sub 1.8}Sr{sub 0.2}NiO{sub 4} and charge and orbital order in Fe{sub 3}O{sub 4}. The main focus of the work was on the spectroscopic potential of the technique, trying to obtain a level of quantitative description of the data. For X-ray absorption spectroscopy (XAS) from transition metal oxides, cluster configuration interaction calculation provides a powerful and realistic microscopic theory. In the frame work of this thesis cluster theory, considering explicit hybridization effects between the TM-ion and the surrounding oxygen ligands, has been applied for the first time to describe resonant diffraction data. (orig.)

X-ray-diffraction and absorption-spectrophotometric studies of AmI/sub 3/ and AmOI

Energy Technology Data Exchange (ETDEWEB)

Haire, R.G.; Young, J.P.; Peterson, J.R.

1983-01-01

The anhydrous tri-iodides and the oxyiodide of americium were investigated by X-ray diffraction and absorption spectrophotometry. From the X-ray analysis of the tri-iodide, an orthorhombic form (PuBr/sub 3/-type structure) has been identified, which is isostructural with the lighter actinide (U-Pu) tri-iodides. A hexagonal form (BiI/sub 3/-type structure) of the tri-iodide was also found. The transition temperature for converting the orthorhombic form to the hexagonal form was established to be 400 +- 30/sup 0/C. Room temperature lattice parameters for the tri-iodide are: (1) a/sub 0/ = 0.428(4), b/sub 0/ = 1.394(1) and c/sub 0/ = 0.9974(7) nm for the orthorbombic form; and (2) a/sub 0/ = 0.7637(4) and c/sub 0/ = 2.091(2) nm for the hexagonal form. Tetragonal parameters for the oxyiodide are a/sub 0/ = 0.4010(3) and c/sub 0/ = 0.9038(6) nm. From differences in the absorption spectra of the solids at 25/sup 0/C, it is possible to differentiate between these three materials by absorption spectrophotometry.

The epitaxial growth and interfacial strain study of VO{sub 2}/MgF{sub 2} (001) films by synchrotron based grazing incidence X-ray diffraction

Energy Technology Data Exchange (ETDEWEB)

Fan, L.L. [Key Laboratory for Advanced Technology in Environmental Protection of Jiangsu Province, Yancheng Institute of Technology, Yancheng 224051 (China); National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei 230029 (China); Chen, S. [National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei 230029 (China); Liu, Q.H. [Science and Technology on Electro-optical Information Security Control Laboratory, Tianjin 300300 (China); Liao, G.M.; Chen, Y.L.; Ren, H. [National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei 230029 (China); Zou, C.W., E-mail: czou@ustc.edu.cn [National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei 230029 (China)

2016-09-05

High quality VO{sub 2} films with different thickness were epitaxially grown on MgF{sub 2} (001) substrates by oxide molecular beam epitaxy method. The evolution of interfacial strain was investigated by synchrotron based grazing incidence X-ray diffraction. By adjusting the incidence angles, the penetration depth of X-ray in VO{sub 2} film could be controlled and the thickness-depend lattice distortion in the epitaxial VO{sub 2} film was investigated. Due to the lattice mismatching, the pronounced tensile strain was observed in ultra-thin VO{sub 2} film. As the film thickness increasing, the interfacial strain relaxed gradually and became fully relaxed for thick VO{sub 2} films. Combined with the electric transport measurement, it was revealed that the phase transition temperature of ultra-thin VO{sub 2} film decreased greatly. The effect of interfacial strain induced phase transition modulation and the intrinsic mechanism was systematically discussed. - Highlights: • We prepared high quality VO{sub 2} epitaxial films on MgF{sub 2} (001) substrates by oxide molecular beam epitaxy method. • Synchrotron radiation grazing incidence X-ray diffraction was employed to detect evolution of strain along depth profile. • Based on a classic band structure model, the mechanism of strain controlled phase transition of VO{sub 2} was discussed.

X-ray emission from a nanosecond-pulse discharge in an inhomogeneous electric field at atmospheric pressure

International Nuclear Information System (INIS)

Zhang Cheng; Shao Tao; Ren Chengyan; Zhang Dongdong; Tarasenko, Victor; Kostyrya, Igor D.; Ma Hao; Yan Ping

2012-01-01

This paper describes experimental studies of the dependence of the X-ray intensity on the anode material in nanosecond high-voltage discharges. The discharges were generated by two nanosecond-pulse generators in atmospheric air with a highly inhomogeneous electric field by a tube-plate gap. The output pulse of the first generator (repetitive pulse generator) has a rise time of about 15 ns and a full width at half maximum of 30–40 ns. The output of the second generator (single pulse generator) has a rise time of about 0.3 ns and a full width at half maximum of 1 ns. The electrical characteristics and the X-ray emission of nanosecond-pulse discharge in atmospheric air are studied by the measurement of voltage-current waveforms, discharge images, X-ray count and dose. Our experimental results showed that the anode material rarely affects electrical characteristics, but it can significantly affect the X-ray density. Comparing the density of X-rays, it was shown that the highest x-rays density occurred in the diffuse discharge in repetitive pulse mode, then the spark discharge with a small air gap, and then the corona discharge with a large air gap, in which the X-ray density was the lowest. Therefore, it could be confirmed that the bremsstrahlung at the anode contributes to the X-ray emission from nanosecond-pulse discharges.

Studies on strain relaxation of La{sub 0.5}Ba{sub 0.5}MnO{sub 3} film by normal and grazing incidence X-ray diffraction

Energy Technology Data Exchange (ETDEWEB)

Wang, Haiou [Hangzhou Dianzi University, Institute of Materials Physics, Hangzhou (China); Tan, Weishi [Hunan City University, College of Communication and Electronic Engineering, Yiyang (China); Nanjing University of Science and Technology, Key Laboratory of Soft Chemistry and Functional Materials, Department of Applied Physics, Ministry of Education, Nanjing (China); Liu, Hao [Suzhou Institute of Industrial Technology, Department of Electronic and Communication Engineering, Suzhou (China); Cao, Mengxiong; Wang, Xingyu; Ma, Chunlin [Nanjing University of Science and Technology, Key Laboratory of Soft Chemistry and Functional Materials, Department of Applied Physics, Ministry of Education, Nanjing (China); Jia, Quanjie [The Chinese Academy of Sciences, Institute of High Energy Physics, Beijing (China)

2017-03-15

Perovskite manganite La{sub 0.5}Ba{sub 0.5}MnO{sub 3} (LBMO) films were deposited on (001)-oriented single-crystal SrTiO{sub 3} (STO) substrates by pulsed laser deposition. High-resolution X-ray diffraction and grazing incidence X-ray diffraction techniques were applied to characterize the crystal structure and lattice strain of LBMO films. The in-plane and out-of-plane growth orientations of LBMO films with respect to substrate surface have been studied. The epitaxial orientation relationship LBMO (001) [100] //STO (001) [100] exists at the LBMO/STO interface. The lattice strain of LBMO film begins to relax with the thickness of LBMO film up to 12 nm. When the thickness is further increased up to 43 nm, the film is in fully strain-relaxed state. Jahn-Teller strain plays an important role in LBMO/STO system. The mechanism for strain relaxation is in accordance with that of tetragonal distortion. (orig.)

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

Energy Technology Data Exchange (ETDEWEB)

Stern, Stephan

2013-12-15

performed on a gas-phase ensemble of the prototypical molecule 2,5-diiodobenzonitrile (C{sub 7}H{sub 3}I{sub 2}N, DIBN) at the X-ray free-electron laser LCLS. The target molecules were laser-aligned along a common axis in the laboratory frame by a Nd:YAG laser. Reaching a strong degree of molecular alignment, was an important step in this experiment. Therefore, a significant part of the work was dedicated to gaining control of the molecular degrees of freedom. In order to reach a high degree of alignment, the target molecules were prepared in low rotational quantum states by means of efficient cooling in a supersonic expansion from a pulsed valve followed by spatial quantum-state selection in an electrostatic deflector. Utilization of the deflector significantly improved alignment of the DIBN molecules. Further applications of the deection technique such as, e.g., the spatial separation of several species of molecular complexes/clusters are presented in this thesis as well. The quantum-state selected and strongly laser-aligned samples were probed by the X-ray pulses of LCLS and the obtained diffraction patterns show a significant difference when comparing diffraction from aligned and isotropically-distributed DIBN which agrees well with theory. The results represent an important step in the effort of pushing diffractive imaging of non-crystalline samples at XFELs towards the single-molecule limit. Concepts and experimental requirements for future experiments of this kind are discussed, involving, e.g., the step towards imaging of laser-aligned large (bio)macromolecules or imaging of ultrafast fragmentation dynamics in femtosecond pump-probe experiments at XFELs.

Structural investigations of interfaces in Fe{sub 90}Sc{sub 10} nanoglasses using high-energy x-ray diffraction

Energy Technology Data Exchange (ETDEWEB)

Ghafari, M.; Gleiter, H.; Feng, T. [Karlsruhe Institute of Technology (KIT), Institute for Nanotechnology, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany); Kohara, S. [Research and Utilization Division, Japan Synchrotron Radiation Research Institute/SPring-8, 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5198 (Japan); Hahn, H.; Witte, R. [Karlsruhe Institute of Technology (KIT), Institute for Nanotechnology, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany); KIT-TUD Joint Research Laboratory Nanomaterials, Technische Universitaet Darmstadt, Petersenstr. 32, 64287 Darmstadt (Germany); Kamali, S. [Department of Chemistry, University of California, One Shields Ave., Davis, California 95616 (United States)

2012-03-26

High-resolution diffraction experiments of Fe{sub 90}Sc{sub 10} nanoglasses and rapidly quenched metallic glasses as reference materials have been performed using high-energy x-rays with a wavelength of 0.21 Angst from a synchrotron radiation source. Nanoglasses are amorphous alloys with a significant fraction of interfaces on the nanometer scale. The short- and intermediate-range orders of a nanoglass are different from the well known amorphous materials produced by rapid quenching from the melt. These structural modifications have significant influence on the physical properties. In this paper, the short- and intermediate-range orders of the nanoglass Fe{sub 90}Sc{sub 10} and the reference metallic glass Fe{sub 90}Sc{sub 10} alloy prepared by rapid quenching are discussed.

X-ray diffraction study of WO{sub 3} at high pressure

Energy Technology Data Exchange (ETDEWEB)

Bouvier, P. [ESRF, Grenoble (France); Laboratoire d' Electrochimie et de Physico-Chimie des Materiaux et des Interfaces UMR 5631 CNRS-INPG, St. Martin d' Heres (France); Crichton, W.A. [ESRF, Grenoble (France); Boulova, M. [Laboratoire d' Electrochimie et de Physico-Chimie des Materiaux et des Interfaces UMR 5631 CNRS-INPG, St. Martin d' Heres (France); Chemistry Department, Moscow State University, Moscow (Russian Federation); Lucazeau, G. [Laboratoire d' Electrochimie et de Physico-Chimie des Materiaux et des Interfaces UMR 5631 CNRS-INPG, St. Martin d' Heres (France)

2002-07-08

The high-pressure behaviour of microcrystalline tungsten oxide (WO{sub 3}) has been investigated with angle-dispersive synchrotron x-ray powder diffraction in a diamond anvil cell up to 40 GPa at room temperature. Up to 21 GPa, the pressure dependence of the volume of the monoclinic high-pressure (P2{sub 1}/c) phase is described by a third-order Birch-Murnaghan equation of state with parameters V{sub 0}=210.9(7)A{sup 3}, K{sub T}=27(2)GP a and K'=9.4(5). At 24 GPa, a first-order phase transition occurs with an approximate {delta} V of 7.4% to a monoclinic P2{sub 1}/a unit cell with a=6.1669(8)A, b=4.5758(6)A, c=5.3159(6)A, {beta}=101.440(9) deg. A second transition is observed at pressures higher than 31 GPa with an approximate {delta} V of 12% to a phase described by a third monoclinic unit cell, with a=10.3633(22)A, b=3.9065(8)A, c=9.3459(18)A and {beta}=98.539(14) deg. (author)

Crystallographic parameters of magnetic Pr{sub 2}Fe{sub 14−x}Co{sub x}B-type alloys determined using anomalous x-ray diffraction with synchrotron radiation

Energy Technology Data Exchange (ETDEWEB)

Galego, E., E-mail: egalego@ipen.br; Serna, M.M.; Ramanathan, L.V.; Faria, R.N.

2017-02-15

Anomalous x-ray synchrotron diffraction was used to determine the crystallographic parameters of PrFeCoB-based magnetic alloys. The effect of cobalt concentration on the crystallographic parameters of the magnetically hard Pr{sub 2}Fe{sub 14−x}Co{sub x}B phase was studied. The results indicate that addition of cobalt has a marked effect on crystal structure. Variation of the c parameter decreased twice as much as the a parameter with increase in Co content. The positions of inequivalent atoms of the magnetically hard matrix phase ϕ in the Pr-based alloys were determined using Rietveld refinement. This permitted determination of the relative distance of each inequivalent atom from its nearest neighbors. Cobalt occupied the 16k{sub 2} site and Fe had a tendency to occupy the 8j{sub 2} sites located between the Kagomé layers. - Highlights: • Good magnetics properties can be achieved with addition of 4% and 8% Co. • Rietveld refinement is proposed for crystallographic parameters studies. • Co has preference to substitute Fe in 16k{sub 2} site and avoid the 8j{sub 2} site.

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

Energy Technology Data Exchange (ETDEWEB)

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

2018-02-01

Quartz has hundreds of strong Bragg reflections that may offer a great number of choices for making fixed-angle X-ray analyzers and polarizers at virtually any hard X-ray energies with selectable resolution. However, quartz crystals, unlike silicon and germanium, are chiral and may thus appear in two different forms of handedness that are mirror images. Furthermore, because of the threefold rotational symmetry along thecaxis, the {h<sub>1sub>h>2sub>h>3sub>L} and {h<sub>2sub>h>1sub>h>3sub>L} Bragg reflections may have quite different Darwin bandwidth, reflectivity and angular acceptance, although they have the same Bragg angle. The design of X-ray optics from quartz crystals therefore requires unambiguous determination of the orientation, handedness and polarity of the crystals. The Laue method and single-axis diffraction technique can provide such information, but the variety of conventions used in the literature to describe quartz structures has caused widespread confusion. The current studies give detailed guidelines for design and fabrication of quartz X-ray optics, with special emphasis on the correct interpretation of Laue patterns in terms of the crystallography and diffraction properties of quartz. Meanwhile, the quartz crystals examined were confirmed by X-ray topography to have acceptably low densities of dislocations and other defects, which is the foundation for developing high-resolution quartz-based X-ray optics.

A study on the microstructural parameters of Zn {sub (1-x)}La{sub x}Zr{sub x}O nanopowders by X-ray line broadening analysis

Energy Technology Data Exchange (ETDEWEB)

Chenari, Hossein Mahmoudi; Moafi, Hadi Fallah; Rezaee, Omid, E-mail: mahmoudi_hossein@guilan.ac.ir, E-mail: hmahmodiph@yahoo.com [Faculty of Science, University of Guilan, Rasht (Iran, Islamic Republic of)

2016-05-15

In the present study, the pure and La-Zr co-doped ZnO nanoparticles were prepared by sol-gel technique using zinc acetate dehydrate (Zn(Ac){sub 2} ·{sub 2}H{sub 2} O), lanthanum nitrate hexahydrate (La(NO{sub 3}){sub 3} ·6H{sub 2}O) and zirconium chloride (ZrCl{sub 4} ) as precursor. The structure and morphology of the prepared nanoparticle samples were studied using X-ray diffraction and transmission electron microscopy measurements. X-ray diffraction results indicated that all the samples have crystalline wurtzite phase. TEM showed that powder was polycrystalline in nature with random distribution of the pure and La-Zr doped ZnO nanoparticles. We demonstrate strain-size evaluations for pure and doped ZnO nanoparticles from the x-ray line profile analysis. The microstructural effects of crystalline materials in terms of crystallite sizes and lattice strain on the peak broadening were investigated using Williamson-Hall (W-H) analysis and size- strain plot (SSP) method. The average crystallite size of Zn {sub (1-x)}La{sub x} Zr{sub x} O nanoparticles estimated from the W-H analysis and SSP method varied as the doping concentration increased. The incorporation of Zr{sup 4+} ion in the place of Zn{sup {sub 2}{sub +}} caused an increase in the size of nanocrystals as compared to undoped ZnO. The average particle sizes of co-doped ZnO nanoparticles estimated from the USDM model is in good agreement with the TEM results. (author)

X-ray topography and multiple diffraction

International Nuclear Information System (INIS)

Chang, S.-L.

1983-01-01

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

Diffraction enhanced x-ray imaging

International Nuclear Information System (INIS)

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

1997-09-01

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

Data processing software suite SITENNO for coherent X-ray diffraction imaging using the X-ray free-electron laser SACLA

International Nuclear Information System (INIS)

Sekiguchi, Yuki; Oroguchi, Tomotaka; Takayama, Yuki; Nakasako, Masayoshi

2014-01-01

The software suite SITENNO is developed for processing diffraction data collected in coherent X-ray diffraction imaging experiments of non-crystalline particles using an X-ray free-electron laser. Coherent X-ray diffraction imaging is a promising technique for visualizing the structures of non-crystalline particles with dimensions of micrometers to sub-micrometers. Recently, X-ray free-electron laser sources have enabled efficient experiments in the ‘diffraction before destruction’ scheme. Diffraction experiments have been conducted at SPring-8 Angstrom Compact free-electron LAser (SACLA) using the custom-made diffraction apparatus KOTOBUKI-1 and two multiport CCD detectors. In the experiments, ten thousands of single-shot diffraction patterns can be collected within several hours. Then, diffraction patterns with significant levels of intensity suitable for structural analysis must be found, direct-beam positions in diffraction patterns determined, diffraction patterns from the two CCD detectors merged, and phase-retrieval calculations for structural analyses performed. A software suite named SITENNO has been developed to semi-automatically apply the four-step processing to a huge number of diffraction data. Here, details of the algorithm used in the suite are described and the performance for approximately 9000 diffraction patterns collected from cuboid-shaped copper oxide particles reported. Using the SITENNO suite, it is possible to conduct experiments with data processing immediately after the data collection, and to characterize the size distribution and internal structures of the non-crystalline particles

Structure of 3 at.% and 9 at.% Si-doped HfO{sub 2} from combined refinement of X-ray and neutron diffraction patterns

Energy Technology Data Exchange (ETDEWEB)

Zhao, Lili [Department of Materials Science and Engineering, North Carolina State University, NC 27695 (United States); School of Information Science and Technology, Northwest University, Xi' an 710127 (China); Hou, Dong; Usher, Tedi-Marie; Iamsasri, Thanakorn; Fancher, Chris M.; Forrester, Jennifer S. [Department of Materials Science and Engineering, North Carolina State University, NC 27695 (United States); Nishida, Toshikazu [Department of Electrical and Computer Engineering, University of Florida, FL 32611 (United States); Moghaddam, Saeed [Department of Mechanical and Aerospace Engineering, University of Florida, FL 32611 (United States); Jones, Jacob L., E-mail: jacobjones@ncsu.edu [Department of Materials Science and Engineering, North Carolina State University, NC 27695 (United States)

2015-10-15

The crystal structure of 3 at.% and 9 at.% Si-doped HfO{sub 2} powder was determined through refinements using X-ray and neutron diffraction patterns. The lattice parameters, atomic positions, dopant occupancy, and the second phase fraction were determined with high precision using a combined full pattern fitting via the Rietveld method. The results show that both 3 at.% and 9 at.% Si-doped HfO{sub 2} powder exhibit the monoclinic crystal structure with P 1 2{sub 1}/c 1 space group. Through the combined refinement, the crystal structure parameters, especially for the positions and occupancies of the lighter atoms, were more precisely determined compared to independent X-ray diffraction refinement. Although the ionic radius of Si{sup 4+} is smaller than Hf{sup 4+}, with increasing Si occupancy, the unit cell volume slightly increases; possible mechanisms for this effect are discussed. Moreover, the refined results provide evidence of the existence of a non-equilibrium phase of Hf{sub x}Si{sub 1−x}O{sub 2}. The second phase (SiO{sub 2}) fraction is determined as 0.17 at.% for 3 at.% Si-doped HfO{sub 2} powders and 1.7 at.% for 9 at.% Si-doped HfO{sub 2} powders. - Highlights: • X-ray and neutron diffraction patterns were used to determine crystal structure. • Results from independent refinements and a combined refinement were compared. • Highly precise structural parameters were obtained by the combined refinement. • Structural data of 3 at.% and 9 at.% Si-doped HfO{sub 2} are provided. • The unit cell volume slightly increases with Si concentration from 3 to 9 at.%.

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

Energy Technology Data Exchange (ETDEWEB)

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)

2012-06-15

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.

Individual GaAs nanorods imaged by coherent X-ray diffraction

Energy Technology Data Exchange (ETDEWEB)

Pietsch, Ullrich; Biermanns, Andreas; Davydok, Anton [Universitaet Siegen (Germany); Paetzelt, Hendrik [Universitaet Leipzig (Germany); IOM Leipzig (Germany); Diaz, Ana; Metzger, Hartmut [ID01 Beamline, ESRF (France); Gottschalch, Volker [Universitaet Leipzig (Germany)

2010-07-01

Semiconductor nanorods are of particular interest for new semiconductor devices because the nanorod approach can be used to form heterostructures of materials with a large lattice mismatch and to define nanorod arrays with tailored inter-rod distance. However, all applications require objects with uniform physical properties based on uniform morphology. Complementary to electron microscopy techniques, destruction free X-ray diffraction techniques can be used to determine structural and morphological details. Using scanning X-ray diffraction microscopy with a spot size of 220 x 600 nm{sup 2} we were able to inspect individual GaAs nanorods grown by seed-free MOVPE through circular openings in a SiN{sub x} mask in a periodic array with 3 {mu}m spacing on GaAs[111]B. The focussed X-ray beam allows the determination of the strain state of individual rods and in combination with coherent diffraction imaging, we were able to characterize also morphological details. Rods grown at different positions in the array show significant differences in shape, size and strain state.

Cation distribution in Ni-substituted Mn{sub 0.5}Zn{sub 0.5}Fe{sub 2}O{sub 4} nanoparticles: A Raman, Mössbauer, X-ray diffraction and electron spectroscopy study

Energy Technology Data Exchange (ETDEWEB)

Thota, Suneetha [Microwave Laboratory, Department of Physics, Indian Institute of Technology Delhi, New Delhi 110016 (India); Kashyap, Subhash C., E-mail: skashyap@physics.iitd.ac.in [Microwave Laboratory, Department of Physics, Indian Institute of Technology Delhi, New Delhi 110016 (India); Sharma, Shiv K. [Hawaii Institute of Geophysics and Planetology, University of Hawaii (UH), Honolulu, HI 96822 (United States); Reddy, V.R. [UGC-DAE Consortium for Scientific Research, Khandwa Road, Indore 452017 (India)

2016-04-15

Graphical abstract: - Highlights: • Synthesized Mn{sub 0.5−x}Ni{sub x}Zn{sub 0.5}Fe{sub 2}O{sub 4}, nanoparticles (0.05 ≤ x ≤ 0.45) at low temperature. • Raman studies established that Fe and Zn ions occupy A site in equal fraction. • {sup 57}Fe Mossbauer study revealed that Ni and Mn ions occupy nearly 25% of B sites. • Electron spectroscopy (XPS) confirmed that nearly 25% Fe{sup 3+} dwells at A sites. • Diffraction peak intensity (X-ray) quantified cations distribution at A- and B-sites. - Abstract: In this paper we report the structural, vibration, and electronic-structure parameters (bonding and valence of cations) of single phase cubic mixed spinel nanoparticles of (Zn{sub δ}Mn{sub γ}Fe{sub 1−(γ+δ)})[Ni{sub x}Zn{sub 0.5−δ}Mn{sub 0.5−γ−x}Fe{sub 1+(γ+δ)}]O{sub 4} where x = 0.05–0.45 with an aim to determine cation-distribution i.e. δ and γ in these samples. The Raman spectroscopy has established that only Fe and Zn cations occupy tetrahedral interstitial sites in a FCC anion lattice in nearly equal fraction, and Mössbauer spectra have shown that Fe{sup 3+} cations are present at both, tetrahedral and octahedral interstitial sites and Ni{sup 2+} cations are situated at the octahedral sites in all the substituted samples. The photoelectron spectra also revealed the presence of Fe{sup 3+} cations at both the interstitial sites. The best possible cationic distribution in Ni substituted Mn–Zn ferrites has been estimated by reiteratively calculating the intensity ratios of various pairs of X-ray diffraction peaks and matching with the observed intensity ratios.

X-ray study of CuGa sub x In sub 1-x Se sub 2 solid solutions

Energy Technology Data Exchange (ETDEWEB)

Suri, D.K.; Nagpal, K.C. (National Physical Lab., New Delhi (India). Materials Characterization Div.); Chadha, G.K. (Delhi Univ. (India). Dept. of Physics and Astrophysics)

1989-12-01

The semiconducting compound CuGa{sub x}In{sub 1-x}Se{sub 2} crystallizes in the chalcopyrite structure (space group Ianti 42d, Z=4). The X-ray powder data for x=1, 0.75, 0.6, 0.5, 0.4, 0.25 and 0.0 have been collected and it is found that the lattice parameters a and c and their ratio c/a vary linearly with x. Thus the composition of any chalcopyrite in the pseudo-binary system CuGaSe{sub 2} and CuInSe{sub 2} can be obtained from the accurate lattice parameters. The crystallite size determined from the (112) plane is minimum for x=0.50 ({proportional to}1000 A) and away from x=0.50 it increases. A value of u=0.240 (5) has been established for fixing, the Se-atom positions in the CuGa{sub 0.5}In{sub 0.5}Se{sub 2} solid solution. The JCPDS Diffraction File No. for CuInSe{sub 2} is 40-1487 and for CuGa{sub 0.5}In{sub 0.5}Se{sub 2} is 40-1488. (orig.).

Spin transitions in La{sub 0.7} Ba{sub 0.3}CoO{sub 3} thin films revealed by combining Raman spectroscopy and X-ray diffraction

Energy Technology Data Exchange (ETDEWEB)

Othmen, Zied; Oueslati, Meherzi [Unité Nanomatériaux et Photonique, Faculty of Sciences of Tunis, Tunis El-Manar University, 2092 Tunis (Tunisia); Copie, Olivier; Gemeiner, Pascale; Dkhil, Brahim [Laboratoire Structures, Propriétés et Modélisation des Solides, Centrale Supélec, CNRS-UMR 8580, Université Paris-Saclay (France); Daoudi, Kais [Unité Nanomatériaux et Photonique, Faculty of Sciences of Tunis, Tunis El-Manar University, 2092 Tunis (Tunisia); Department of Applied Physics and Astronomy, College of Sciences, University of Sharjah, P.O. Box 27272, Sharjah (United Arab Emirates); Boudard, Michel [Univ. Grenoble Alpes, LMGP, F-38000 Grenoble (France)

2016-07-07

In cobaltite, the spin states transitions of Co{sup 3+/4+} ions govern the magnetic and electronic conduction properties. These transitions are strain-sensitive and can be varied using external parameters, including temperature, hydrostatic pressure, or chemical stresses through ionic substitutions. In this work, using temperature dependent Raman spectroscopy and X-ray diffraction, the epitaxial strain effects on both structural and vibrational properties of La{sub 0.7} Ba{sub 0.3} CoO{sub 3} (LBCO) cobaltite thin films are investigated. All Raman active phonon modes as well as the structure are found to be strongly affected. Both Raman modes and lattice parameter evolutions show temperature changes correlated with magnetic and electronic transitions properties. Combining Raman spectroscopy and X-ray diffraction appears as a powerful approach to probe the spin transition in thin film cobaltite. Our results provide insight into strong spin-charge-phonon coupling in LBCO thin film. This coupling manifests as vibrational transition with temperature in the Raman spectra near the ferromagnetic spin ordered transition at 220 K.

Diffraction peaks in x-ray spectroscopy: Friend or foe?

International Nuclear Information System (INIS)

Tissot, R.G.; Goehner, R.P.

1992-01-01

Diffraction peaks can occur as unidentifiable peaks in the energy spectrum of an x-ray spectrometric analysis. Recently, there has been increased interest in oriented polycrystalline films and epitaxial films on single crystal substrates for electronic applications. Since these materials diffract x-rays more efficiently than randomly oriented polycrystalline materials, diffraction peaks are being observed more frequently in x-ray fluorescent spectra. In addition, micro x-ray spectrometric analysis utilizes a small, intense, collimated x-ray beam that can yield well defined diffraction peaks. In some cases these diffraction peaks can occur at the same position as elemental peaks. These diffraction peaks, although a possible problem in qualitative and quantitative elemental analysis, can give very useful information about the crystallographic structure and orientation of the material being analyzed. The observed diffraction peaks are dependent on the geometry of the x-ray spectrometer, the degree of collimation and the distribution of wavelengths (energies) originating from the x-ray tube and striking the sample

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

Energy Technology Data Exchange (ETDEWEB)

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

2007-11-01

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

New structural studies of liquid crystal by reflectivity and resonant X-ray diffraction; Nouvelles etudes structurales de cristaux liquides par reflectivite et diffraction resonante des rayons X

Energy Technology Data Exchange (ETDEWEB)

Fernandes, P

2007-04-15

This memory presents three structural studies of smectic Liquid Crystals by reflectivity and resonant diffraction of X-rays. It is divided in five chapters. In the first a short introduction to Liquid Crystals is given. In particular, the smectic phases that are the object of this study are presented. The second chapter is consecrated to the X-ray experimental techniques that were used in this work. The three last chapters present the works on which this thesis can be divided. Chapter three demonstrates on free-standing films of MHPOBC (historic liquid crystal that possesses the antiferroelectric sub-phases) the possibility to extend the technique of resonant X-ray diffraction to liquid crystals without resonant element. In the fourth chapter the structure of the B{sub 2} liquid crystal phase of bent-core molecules (or banana molecules) is elucidated by using resonant X-ray diffraction combined with polarization analysis of the diffracted beam. A model of the polarization of the resonant beam diffracted by four different structures proposed for the B{sub 2} phase is developed in this chapter. In the fifth chapter a smectic binary mixture presenting a very original critical point of phase separation is studied by X-ray reflectivity and optical microscopy. A concentration gradient in the direction perpendicular to the plane of the film seems to be induced by the free-standing film geometry. The results of a simplified model of the system are compatible with this interpretation.

Neptunium octupole and hexadecapole motif in NpO sub 2 directly from electric-dipole (E1) enhanced x-ray Bragg diffraction

CERN Document Server

Lovesey, S W; Detlefs, C; Laan, G V D; Sivia, D S; Staub, U

2003-01-01

The phase transition in NpO sub 2 at T sub o approx 25.5K is accompanied by the onset of superlattice reflections in the x-ray Bragg diffraction pattern, with intensity enhanced by an electric-dipole (E1) event. Additional experiments using other techniques indicate no ordering at T sub o of Np magnetic moments. Absence of long-range magnetic order below T sub o fits with the outcome of a polarization analysis of superlattice intensities at 12K; signals are observed in both the unrotated (sigma'sigma) and rotated (pi'sigma) channels of scattering while magnetic (dipole) moments would contribute only in the rotated channel. We demonstrate that these empirical findings, together with a narrow energy profile of the Bragg intensity at the Np M sub 4 edge, are consistent with magnetic and charge contributions to the El Bragg amplitude described by Np 5f multipoles of ranks 3 (octupole) and 4 (hexadecapole). Key to our understanding of the x-ray diffraction data gathered in the vicinity of the Np M sub 4 edge is re...

Time-Resolved Soft X-ray Diffraction Reveals Transient Structural Distortions of Ternary Liquid Crystals

Directory of Open Access Journals (Sweden)

Klaus Mann

2009-11-01

Full Text Available Home-based soft X-ray time-resolved scattering experiments with nanosecond time resolution (10 ns and nanometer spatial resolution were carried out at a table top soft X-ray plasma source (2.2–5.2 nm. The investigated system was the lyotropic liquid crystal C16E7/paraffin/glycerol/formamide/IR 5. Usually, major changes in physical, chemical, and/or optical properties of the sample occur as a result of structural changes and shrinking morphology. Here, these effects occur as a consequence of the energy absorption in the sample upon optical laser excitation in the IR regime. The liquid crystal shows changes in the structural response within few hundred nanoseconds showing a time decay of 182 ns. A decrease of the Bragg peak diffracted intensity of 30% and a coherent macroscopic movement of the Bragg reflection are found as a response to the optical pump. The Bragg reflection movement is established to be isotropic and diffusion controlled (1 μs. Structural processes are analyzed in the Patterson analysis framework of the time-varying diffraction peaks revealing that the inter-lamellar distance increases by 2.7 Å resulting in an elongation of the coherently expanding lamella crystallite. The present studies emphasize the possibility of applying TR-SXRD techniques for studying the mechanical dynamics of nanosystems.

Crystallized solids characterization by X-ray diffraction

International Nuclear Information System (INIS)

Broll, N.

1996-01-01

This work deals with the crystallized solids characterization by X-ray diffraction. The powders diffraction principle is described. Then are given the different powders diffraction experimental methods. An X-ray diffraction device is essentially constituted of three parts: the X-rays source, the sample and the detector. The source is usually constituted by an X-rays tube whereas the sample can be fixed on a photographic chamber or put on a goniometer. The different photographic chambers which can be used (Debye-Scherrer, Seeman-Bohlin and Guinier) are described. The powders diffractometer the most used is a Bragg-Brentano focusing diffractometer because it allows to obtain very sharp spectral lines and an important diffracted intensity. The detectors which are the mainly used are the scintillation counters. The most important use in powders diffractometry is the identification of the different phases of a sample. The phases identification consists to compare the unknown sample spectrum at those of standard materials indexed until now. Two methods exist at present. They are explained and their limits in the phases search are given. Another use of the X-ray diffraction is the quantitative analysis. It consists to determine the concentrations of each crystal phases of a sample. The principles of these quantitative methods are given. The lattice parameters of a polycrystal material can be determined from its X-ray pattern too with a very high precision. The way to index powders patterns is given. The residual stresses of materials can also be estimated. The principle of this measured method is explained. It is at last possible to study from an X-ray pattern, the material grain orientations during the different steps of preparation and working. (O.M.). 13 refs., 19 figs., 1 tab

Phase transitions of Cu.sub.3+x./sub.Si observed by temperature-dependent x-ray powder diffraction

Czech Academy of Sciences Publication Activity Database

Correa, Cinthia Antunes; Poupon, Morgane; Kopeček, Jaromír; Král, Robert; Zemenová, Petra; Lecourt, J.; Barrier, N.; Brázda, Petr; Klementová, Mariana; Palatinus, Lukáš

2017-01-01

Roč. 91, Dec (2017), s. 129-139 ISSN 0966-9795 R&D Projects: GA ČR GC15-08842J Institutional support: RVO:68378271 Keywords : X-ray powder diffraction * differential scanning calorimetry * phase transitions * Cu3+xSi Subject RIV: BM - Solid Matter Physics ; Magnetism OBOR OECD: Condensed matter physics (including formerly solid state physics, supercond.) Impact factor: 3.140, year: 2016

X-ray diffraction, dielectric, and Raman spectroscopy studies of BaSrTiO{sub 3}-NaNbO{sub 3} ceramic

Energy Technology Data Exchange (ETDEWEB)

Abdessalem, L. Ben; Aydi, S.; Aydi, A.; Maalej, A.; Khemakhem, H. [Universite de Sfax, Laboratoire des Materiaux Multifonctionnels et Applications (LaMMA), Faculte des Sciences de Sfax (FSS), Sfax (Tunisia); Sassi, Z. [Laboratoire de Genie Electrique et Ferroelectricite (LGEF) de L' INSA de Lyon, Villeurbanne (France)

2017-05-15

Ba{sub 0.837}Sr{sub 0.093}Na{sub 0.07}Ti{sub 0.93}Nb{sub 0.07}O{sub 3} (BSNTN) ceramic was synthesized by the solid-state reaction at 1350 C for 3 h. The crystal structure, investigated by X-ray diffraction at room temperature, revealed a single-phase perovskite crystallizing with tetragonal P4mm group space. Dielectric properties were investigated as a function of applied frequency. The ferroelectric behavior has been confirmed by hysteresis investigation. The evolution of the Raman spectra was used to study the variations of the basic phase transition of BaTiO{sub 3}, at room temperature. It shows the introduction of a disorder in this composition, thus favoring a ferroelectric relaxor behavior. (orig.)

In situ X-ray diffraction studies on the piezoelectric response of PZT thin films

Energy Technology Data Exchange (ETDEWEB)

Davydok, A., E-mail: davydok@mpie.de [Aix Marseille Université, CNRS, Université de Toulon, IM2NP UMR 7334, 13397 Marseille (France); Max-Planck-Institut für Eisenforschung, Department Structure and Nano-/Micromechanics of Materials, D-40237 Düsseldorf (Germany); Cornelius, T.W. [Aix Marseille Université, CNRS, Université de Toulon, IM2NP UMR 7334, 13397 Marseille (France); Mocuta, C. [SOLEIL Synchrotron, DiffAbs beamline, L' Orme des Merisiers, Saint-Aubin - BP 48, 91192 Gif-sur-Yvette Cedex (France); Lima, E.C. [Universidade Federal do Tocantins, 77500-000 Porto Nacional, TO (Brazil); Araujo, E.B. [Departamento de Fisica e Quimica, Universidade Estadual Paulista, Av. Brasil, 56 Centro, 15385-000 Ilha Solteira, SP (Brazil); Thomas, O. [Aix Marseille Université, CNRS, Université de Toulon, IM2NP UMR 7334, 13397 Marseille (France)

2016-03-31

Piezoelectric properties of randomly oriented self-polarized PbZr{sub 0.50}Ti{sub 0.50}O{sub 3} (PZT) thin films were investigated using in situ synchrotron X-ray diffraction. Possibilities for investigating the piezoelectric effect using micro-sized hard X-ray beams are demonstrated and perspectives for future dynamical measurements on PZT samples with variety of compositions and thicknesses are given. Studies performed on the crystalline [100, 110] directions evidenced piezoelectric anisotropy. The piezoelectric coefficient d{sub 33} was calculated in terms of the lab reference frame (d{sub perp}) and found to be two times larger along the [100] direction than along the [110] direction. The absolute values for the d{sub perp} amount to 120 and 230 pm/V being in good agreement with experimental and theoretical values found in literature for bulk PZT ceramics. - Highlights: • We performed in situ synchrotron X-ray diffraction studies on (PZT) thin films. • We discuss anisotropy of piezo effect in different crystallographic directions. • Perpendicular component Piezo coefficient of thin PZT layer is defined.

In situ electrochemical high-energy X-ray diffraction using a capillary working electrode cell geometry

Energy Technology Data Exchange (ETDEWEB)

Young, Matthias J.; Bedford, Nicholas M.; Jiang, Naisheng; Lin, Deqing; Dai, Liming

2017-05-26

The ability to generate new electrochemically active materials for energy generation and storage with improved properties will likely be derived from an understanding of atomic-scale structure/function relationships during electrochemical events. Here, the design and implementation of a new capillary electrochemical cell designed specifically forin situhigh-energy X-ray diffraction measurements is described. By increasing the amount of electrochemically active material in the X-ray path while implementing low-Zcell materials with anisotropic scattering profiles, an order of magnitude enhancement in diffracted X-ray signal over traditional cell geometries for multiple electrochemically active materials is demonstrated. This signal improvement is crucial for high-energy X-ray diffraction measurements and subsequent Fourier transformation into atomic pair distribution functions for atomic-scale structural analysis. As an example, clear structural changes in LiCoO<sub>2sub>under reductive and oxidative conditions using the capillary cell are demonstrated, which agree with prior studies. Accurate modeling of the LiCoO<sub>2sub>diffraction data using reverse Monte Carlo simulations further verifies accurate background subtraction and strong signal from the electrochemically active material, enabled by the capillary working electrode geometry.

100 years of discovery of X-ray diffraction

International Nuclear Information System (INIS)

Zhang Tao

2012-01-01

X-ray diffraction was discovered by Max von Laue a hundred years ago. Later, through the work of William H. Bragg and William L. Bragg, an experimental analysis method was developed to solve the structure of molecules at the atomic level. Over the past hundred years, science and technology has been dramatically changed by X-ray diffraction analysis, which has also undergone considerable development. The recent emergence of hard X-ray free electron lasers has provided a new dimension for X-ray diffraction analysis, promising even greater progress in the fields of physics, chemistry and biology. (author)

Diffracted X-ray tracking: new system for single molecular detection with X-rays

CERN Document Server

Sasaki, Y C; Adachi, S; Suzuki, Y; Yagi, N

2001-01-01

We propose a new X-ray methodology for direct observations of the behaviors of single molecular units in real time and real space. This new system, which we call Diffracted X-ray Tracking (DXT), monitors the Brownian motions of a single molecular unit by observations of X-ray diffracted spots from a nanocrystal, tightly bound to the individual single molecular unit in bio-systems. DXT does not determine any translational movements, but only orientational movements.

Diffracted X-ray tracking: new system for single molecular detection with X-rays

International Nuclear Information System (INIS)

Sasaki, Y.C.; Okumura, Y.; Adachi, S.; Suzuki, Y.; Yagi, N.

2001-01-01

We propose a new X-ray methodology for direct observations of the behaviors of single molecular units in real time and real space. This new system, which we call Diffracted X-ray Tracking (DXT), monitors the Brownian motions of a single molecular unit by observations of X-ray diffracted spots from a nanocrystal, tightly bound to the individual single molecular unit in bio-systems. DXT does not determine any translational movements, but only orientational movements

X-ray and neutron scattering investigations of YCo sub 3 -H

Energy Technology Data Exchange (ETDEWEB)

Benham, M J; Bennington, S M; Ross, D K [Birmingham Univ. (UK). School of Physics and Space Research; Noreus, D [Stockholm Univ. (Sweden). Dept. of Structural Chemistry; Yamaguchi, M [Yokohoma National Univ. (Japan). Dept. of Electrical and Computer Engineering

1989-01-01

Various structural studies of YCo{sub 3}H(D){sub x} in the {beta}-phase (0<x<2) are described, where hydrogenation induces a cyclic variation between ferromagnetic and paramagnetic states. X-ray diffraction measurements determined that the expansion of the lattice is localised to components of the structure which are related to the Laves phase, YCo{sub 2}. Neutron diffraction and inelastic neutron scattering were also used in tandem, and hydrogen occupation of a single (36i) tetrahedral site was inferred for the entire concentration range. (orig.).

Introducing the ARL X'Tra x-ray diffraction system

International Nuclear Information System (INIS)

Harris, L.

2002-01-01

Full text: The ARL X'Tra is a state-of-the-art solution for powder X-ray diffraction in a large range of applications such as pharmaceuticals and biosciences, chemicals, earth sciences, semi-conductors, metallurgy and ceramics. The X'Tra offers the latest technology in key diffraction components to produce a high performance instrument at an affordable price. This presentation examines some of the hardware and performance features of this instrument. Copyright (2002) Australian X-ray Analytical Association Inc

Electrical conductivity, differential scanning calorimetry, X-ray diffraction, and {sup 7}Li nuclear magnetic resonance studies of n-C{sub x}H{sub (2x+1)}OSO{sub 3}Li (x = 12, 14, 16, 18, and 20)

Energy Technology Data Exchange (ETDEWEB)

Hirakawa, Satoru [Yokohama City University, Graduate School of Nanobioscience (Japan); Morimoto, Yoshiaki [Yokohama City University, International College of Arts and Sciences (Japan); Honda, Hisashi, E-mail: hhonda@yokohama-cu.ac.jp [Yokohama City University, Graduate School of Nanobioscience (Japan)

2015-04-15

Electrical conductivity (σ), differential scanning calorimetry (DSC), and X-ray diffraction (XRD) measurements of n-C {sub x}H{sub (2x+1)}OSO{sub 3}Li (x= 12, 14, 16, 18, and 20) crystals were performed as a function of temperature. In addition, σ, DSC, and XRD observations of n-C {sub x}H{sub (2x+1)}OSO{sub 3}Na and n-C {sub x}H{sub (2x+1)}OSO{sub 3}K (x= 12, 14, 16, 18, and 20) crystals were carried out for comparison. DSC results of the salts revealed several solid-solid phase transitions with large entropy changes (ΔS). For n-C {sub 18}H{sub 37}OSO{sub 3}Li and n-C {sub 20}H{sub 41}OSO{sub 3}Li salts, each melting point produced a small ΔS{sub mp} value compared with the total entropy change in the solid phases (ΔS{sub tr1}+ΔS{sub tr2}). Additionally, Li {sup +} ion diffusion was detected in the highest temperature solid phases. For K salts, larger σ values were detected for potassium alkylsulfates compared with those reported for alkyl carboxylate. {sup 7}Li NMR spectra of n-C {sub 18}H{sub 37}OSO{sub 3}Li crystals recorded in the low-temperature phase showed large asymmetry parameters, suggesting the Li {sup +} ions are localized at asymmetric sites in the crystals.

Characterization of crystalline phases of (U,Er)O{sub 2} pellets by X-Ray diffraction

Energy Technology Data Exchange (ETDEWEB)

Sansone, Alberto E.S.; Riella, Humberto G.; Carvalho, Elita F. U. de, E-mail: alberto.sansone@usp.br, E-mail: riella@enq.ufsc.br, E-mail: elitaucf@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

2017-07-01

Optimization of nuclear fuel for use in pressurized water reactors can be achieved by obtaining higher burnups. This, however, requires the excess reactivity caused by increasing the fuel's enrichment to be taken into account, which can be done by introducing burnable absorbers into the UO{sub 2} fuel pellets themselves. Some of the rare earth elements have thermal and mechanical properties that make them appropriate for use inside the reactor. In order to characterize the microstructure of erbium-doped UO{sub 2} fuel, sintered UO{sub 2}-Er{sub 2}O{sub 3} pellets were prepared, with Er{sub 2}O{sub 3} content ranging from 1:0 to 9:8wt%, and analyzed by X-ray diffraction to determine whether the composite formed solid solutions and, if so, evaluate the lattice parameter as a function of erbia concentration. While XRD analysis showed the Er{sub 2}O{sub 3} completely dissolved in the UO{sub 2} powder, it also evidenced the emergence of a second fluorite-type phase, whose phase fraction increases and lattice parameter decreases with increasing erbia concentration. Analysis of the diffraction patterns showed this emerging phase has the same crystalline structure as the host lattice, but with a smaller lattice parameter, and a smaller domain size. These results are compatible with the phenomenon of defect segregation, which consists in the formation of microdomains with a higher concentration of defects. (author)

Ultrafast coherent diffractive imaging of nanoparticles using X-ray free-electron laser radiation

International Nuclear Information System (INIS)

Kassemeyer, Stephan

2014-01-01

reduced to one-dimensional sub-problems by arranging diffraction patterns in geodesic similarity sequences. Relations between the one-dimensional sub-problems are established by identifying rotations about the X-ray axis and one-dimensional solutions are combined into a three-dimensional orientation recovery. The global optimization approach ensures that information is extracted from the whole diffraction dataset, not only individual diffraction patterns. Therefore this method can cope with diffraction data sets consisting of individual diffraction patterns with weak signals. The geodesic approach can handle datasets from inhomogeneous samples as well as samples with symmetries. A successful application to experimental X-FEL data is shown, resulting in the first three-dimensional reconstruction of a nanoparticle using X-FEL coherent diffractive imaging.

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

Energy Technology Data Exchange (ETDEWEB)

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

2013-07-01

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

Classification of glutinous rice (Oryza sativa L.) starches based on X-ray diffraction pattern

Energy Technology Data Exchange (ETDEWEB)

Zhang, Q.; Abe, T.; Ando, H.; Sasahara, T.

1993-07-01

This study was carried out to analyse the cultivar variability of the X-ray diffraction pattern of glutinous rice starches. Four peaks in the X-ray diffractograms were identified, i.e. 3b, 4a, 4b and 6a. The four peaks were measured from the base line for 71 cultivars and three M{sub 3} lines which were irradiated by γ-rays at the rates of 10, 20 and 30 kr, respectively. Glutinous rice starches were classified into two types by discriminant analysis based on the values of 3b/4b, 4a/4b and 6a/4b. The X-ray diffraction type of the three cultivars did not change with the cultivation areas of different latitude, while that of eleven cultivars varied. Degree of crystallinity was estimated using the formula, (I{sub max} — I{sub i})/I{sub max} where I{sub max} is the maximum height from background intensity line among cultivars, and I{sub i} represents the four peaks. These ratios indicated that the changes in the order of crystallinity were similar to those with the water content and/or hydration and temperature for gelatinization among and/or within cultivars. (author)

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

Energy Technology Data Exchange (ETDEWEB)

Maddox, B. R., E-mail: maddox3@llnl.gov; Akin, M. C., E-mail: akin1@llnl.gov; Teruya, A.; Hunt, D.; Hahn, D.; Cradick, J. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Morgan, D. V. [National Security Technologies LLC, Los Alamos, New Mexico 87544 (United States)

2016-08-15

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

High-pressure X-ray diffraction studies of potassium chlorate

Energy Technology Data Exchange (ETDEWEB)

Pravica, Michael; Bai, Ligang; Bhattacharya, Neelanjan (UNLV)

2012-03-15

Two static high-pressure X-ray diffraction (XRD) studies of potassium chlorate have been performed at pressures of up to {approx}14.3 GPa in a diamond anvil cell at ambient temperature using the 16 ID-B undulator beamline at the Advanced Photon Source for the X-ray source. The first experiment was conducted to ascertain decomposition rates of potassium chlorate as a function of pressure. Below 2 GPa, the sample was observed to decompose rapidly in the presence of the X-ray beam and release oxygen. Above 2 GPa (near the phase I phase II transition), the decomposition rate dramatically slowed so that good quality XRD patterns could be acquired. This suggests a phase-dependent decomposition rate. In the second study, X-ray diffraction spectra were collected at pressures from 2 to 14.3 GPa by aligning virgin portions of the sample into the focused X-ray beam at each pressure. The results suggest the co-existence of mixed monoclinic (I) and rhombohedral (II) phases of potassium chlorate near 2 GPa. At pressures beyond 4 GPa, the XRD patterns show a very good fit to KClO{sub 3} in the rhombohedral phase with space group R3m, in agreement with earlier studies. No further phase transitions were observed with pressure. Decompression of the sample to ambient pressure indicated mixed phases I and II coupled with a small amount of synchrotron X-ray-induced decomposition product. The equation of state within this pressure regime has been determined.

X-ray diffraction, Raman and photoacoustic studies of InSb nanocrystals

Energy Technology Data Exchange (ETDEWEB)

Ersching, K., E-mail: kleb85@hotmail.com [Departamento de Fisica, Universidade Federal de Santa Catarina, Campus Universitario Trindade, 88040-900 Florianopolis, Santa Catarina (Brazil); Campos, C.E.M.; Lima, J.C. de; Grandi, T.A. [Departamento de Fisica, Universidade Federal de Santa Catarina, Campus Universitario Trindade, 88040-900 Florianopolis, Santa Catarina (Brazil); Souza, S.M. [Departamento de Engenharia Mecanica, Universidade Federal de Santa Catarina, Campus Universitario Trindade, 88040-900 Florianopolis, Santa Catarina (Brazil); Pizani, P.S. [Departamento de Fisica, Universidade Federal de Sao Carlos, 13 565-905 Sao Carlos, SP (Brazil)

2010-08-01

Zinc blend InSb nanocrystals were generated by mechanical alloying and X-ray diffraction, Raman spectroscopy and photoacoustic absorption spectroscopy techniques were used to study its structural, optical and thermal properties. Annealed nanocrystals were also studied. Residual amorphous and minority crystalline (Sb and In{sub 2}O{sub 3}) phases were also observed for mechanical alloyed and thermal annealed samples, respectively. The structural parameters, phase fractions, average crystallite sizes and microstrains of all crystalline phases found in the samples were obtained from Rietveld analyses of their X-ray diffraction patterns. Raman results for both as-milled and annealed samples show the Raman active LO and TO modes of the zinc blend InSb phase and Sb-rich regions. The photoacoustic results of both samples were satisfactorily explained by thermal bending heat transfer mechanism and an increase on effective thermal diffusivity coefficient was observed after annealing.

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

Energy Technology Data Exchange (ETDEWEB)

Saikia, B.K.; Boruah, R.K.; Gogoi, P.K. [CSIR, Jorhat (India)

2009-01-15

The so-called turbostatic structure of carbons in coal with randomly oriented stacking of the lamellae (graphene) produces intense peaks, which are the dominant features in its X-ray diffraction profiles. The diffractogram may be conveniently divided into two regions of reciprocal space, the medium S region (1 < S < 3 {angstrom}) and a high S region (S > 3 {angstrom}) where S = 4 {pi} {lambda} {sup -1}sin{theta}. To better understand the molecular level structure of high sulphur Assam coal, two coal samples (Tirap-1 and Tirap-2) from Tirap colliery of Makum coalfield, Assam (India) has been interpreted in this study by using the X-ray diffraction profiles. Random layered (graphene) structural parameters of these coals were determined by using X-ray diffraction technique, which showed that the L{sub a} and L{sub c} are 64.99 angstrom and 22.63 angstrom for Tirap-2 and 55.54 angstrom and 23.80 angstrom for that of Tirap-1 coals respectively. The position of {gamma} band was found to be at 4.34 {angstrom} and 4.13 angstrom for Tirap-2 and Tirap-1 coals respectively. The number of layers and average number of carbon atoms (N) per aromatic graphene were found to be 21 and 8 for both the coal samples. Proximate, ultimate and ash analysis of the two coal samples were also carried out in this investigation.

Structure and dielectric properties of (Ba{sub 0.7}Sr{sub 0.3}){sub 1-x}Na{sub x}(Ti{sub 0.9}Sn{sub 0.1}){sub 1-x}Nb{sub x}O{sub 3} ceramics

Energy Technology Data Exchange (ETDEWEB)

Ghoudi, Hanen; Khirouni, Kamel [Universite de Gabes, Laboratoire de Physique des Materiaux et des Nanomateriaux Appliquee a l' Environnement (La Phy MNE), Faculte des Sciences de Gabes, Gabes (Tunisia); Chkoundali, Souad [Universite de Sfax, Laboratoire des Materiaux Multifonctionnels et Applications (LaMMA), Faculte des Sciences de Sfax (FSS), Sfax (Tunisia); Aydi, Abdelhedi [Universite de Gabes, Laboratoire de Physique des Materiaux et des Nanomateriaux Appliquee a l' Environnement (La Phy MNE), Faculte des Sciences de Gabes, Gabes (Tunisia); Universite de Sfax, Laboratoire des Materiaux Multifonctionnels et Applications (LaMMA), Faculte des Sciences de Sfax (FSS), Sfax (Tunisia)

2017-11-15

(Ba{sub 0.7}Sr{sub 0.3}){sub 1-x}Na{sub x}(Ti{sub 0.9}Sn{sub 0.1}){sub 1-x}Nb{sub x}O{sub 3} ceramics with compositions x = 0.6, 0.7, 0.8 and 0.9 were synthesized using the solid-state reaction method. These ceramics were examined by X-ray diffraction and dielectric measurements over a broad temperature and frequency ranges. X-ray diffraction patterns revealed a single-perovskite phase crystallized in a cubic structure, for x < 0.8, and in tetragonal, for x ≥ 0.8, with Pm3m and P4mm spaces groups, respectively. Two types of behaviors, classical ferroelectric or relaxor, were observed depending on the x composition. It is noted that temperatures T{sub C} (the Curie temperature) or T{sub m} (the temperature of maximum permittivity) rise when x increases and the relaxor character grows more significantly when x composition decreases. To analyze the dielectric relaxation degree of relaxor, various models were considered. It was proven that an exponential function could well describe the temperature dependence of the static dielectric constant and relaxation time. (orig.)

Three-dimensional x-ray diffraction detection and visualization

International Nuclear Information System (INIS)

Allahkarami, Masoud; Hanan, Jay C

2014-01-01

A new method of sensing and analyzing three-dimensional (3D) x-ray diffraction (XRD) cones was introduced. Using a two-dimensional area detector, a sequence of frames was collected while moving the detector away from the sample with small equally spaced steps and keeping all other parameters constant. A 3D dataset was created from the subsequent frames. The 3D x-ray diffraction (XRD 3 ) pattern contains far more information than a one-dimensional profile collected with the conventional diffractometer and 2D x-ray diffraction (XRD 2 ). The present work discusses some fundamentals about XRD 3 , such as the data collection method, 3D visualization, diffraction data interpretation and potential applications of XRD 3 . (paper)

High resolution x-ray diffraction analyses of GaN/LiGaO{sub 2}

Energy Technology Data Exchange (ETDEWEB)

Matyi, R.J. [Department of Materials Science and Engineering University of Wisconsin, Madison, WI (United States); Doolittle, W.A.; Brown, A.S. [School of Electrical and Computer Engineering Georgia Institute of Technology, Atlanta, GA (United States)

1999-05-21

Lithium gallate (LiGaO{sub 2}) is gaining increasing attention as a potential substrate for the growth of the important semiconductor GaN. In order to better understand this material we have performed high-resolution double- and triple-axis x-ray diffraction analyses of both the starting LiGaO{sub 2} and GaN/LiGaO{sub 2} following epitaxial growth. A high-resolution triple-axis reciprocal space map of the substrate showed a sharp, well-defined crystal truncation rod and a symmetric streak of intensity perpendicular to q{sub 002}, suggesting high structural quality with mosaic spread. Triple-axis scans following GaN growth showed (1) the development of isotropic diffuse scatter around the LiGaO{sub 2} (002) reflection, (2) the presence of a semi-continuous intensity streak between the LiGaO{sub 2} (002) and GaN (0002) reflections, and (3) a compact pattern of diffuse scatter around the GaN (0002) reflection that becomes increasingly anisotropic as the growth temperature is increased. These results suggest that LiGaO{sub 2} permits the epitaxial growth of GaN with structural quality that may be superior to that observed when growth is performed on SiC or Al{sub 2}O{sub 3}. (author)

Structural phase transitions in Bi[sub 2]V[sub 1[minus]x]Ge[sub x]O[sub 5. 5[minus]x/2] (x = 0. 2, 0. 4, and 0. 6) single crystals: X-ray crystallographic study

Energy Technology Data Exchange (ETDEWEB)

Sooryanarayana, K.; Guru Row, T.N.; Varma, K.B.R. (Indian Inst. of Science, Bangalore (India))

1999-02-01

Single crystals of Bi[sub 2]V[sub 1[minus]x]Ge[sub x]O[sub 5.5[minus]x/2] (x = 0.2, 0.4, and 0.6) were grown by slow cooling of melts. Bismuth vanadate transforms from an orthorhombic to a tetragonal structure and subsequently to an orthorhombic system when the Ge[sup 4+] concentration was varied from x = 0.2 to x = 0.6. All of these compositions crystallized in polar space groups (Aba2, F4mm, and Fmm2 for x = 0.2, 0.4, and 0.6, respectively). The structures were fully determined by single crystal X-ray diffraction studies.

Crystallization and preliminary X-ray diffraction analysis of the glucuronoyl esterase catalytic domain from Hypocrea jecorina

Energy Technology Data Exchange (ETDEWEB)

Wood, S. J. [Biosciences Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Li, X.-L.; Cotta, M. A. [Fermentation Biotechnology Research Unit, National Center for Agricultural Utilization Research, USDA-ARS, Peoria, Illinois 61604 (United States); Biely, P. [Institute of Chemistry, Slovak Academy of Sciences, 845 38 Bratislava (Slovakia); Duke, N. E. C.; Schiffer, M.; Pokkuluri, P. R., E-mail: rajp@anl.gov [Biosciences Division, Argonne National Laboratory, Argonne, IL 60439 (United States)

2008-04-01

The catalytic domain of the glucuronoyl esterase from H. jecorina was overexpresssed, purified and crystallized in space group P2{sub 1}2{sub 1}2{sub 1}. X-ray diffraction data were collected to 1.9 Å resolution. The catalytic domain of the glucuronoyl esterase from Hypocrea jecorina (anamorph Trichoderma reesei) was overexpresssed, purified and crystallized by the sitting-drop vapor-diffusion method using 1.4 M sodium/potassium phosphate pH 6.9. The crystals belonged to space group P2{sub 1}2{sub 1}2{sub 1} and X-ray diffraction data were collected to 1.9 Å resolution. This is the first enzyme with glucoronoyl esterase activity to be crystallized; its structure will be valuable in lignocellulose-degradation research.

Surface structure of Bi<sub>2sub>Se>3sub>(111) determined by low-energy electron diffraction and surface x-ray diffraction

DEFF Research Database (Denmark)

dos Reis, Diogo Duarte; Barreto, Lucas; Bianchi, Marco

2013-01-01

The surface structure of the prototypical topological insulator Bi2Se3 is determined by low-energy electron diffraction and surface x-ray diffraction at room temperature. Both approaches show that the crystal is terminated by an intact quintuple layer. Specifically, an alternative termination by ...... by a bismuth bilayer is ruled out. Surface relaxations obtained by both techniques are in good agreement with each other and found to be small. This includes the relaxation of the van der Waals gap between the first two quintuple layers....

Stress evaluation in thin films: Micro-focus synchrotron X-ray diffraction combined with focused ion beam patterning for d{sub o} evaluation

Energy Technology Data Exchange (ETDEWEB)

Baimpas, Nikolaos, E-mail: nikolaos.baimpas@eng.ox.ac.uk [University of Oxford, Dept. of Engineering Science (United Kingdom); Le Bourhis, Eric [University of Poitiers, Institut P' , Laboratoire de Physique des Matériaux, Poitiers (France); Eve, Sophie [ENSICAEN, CRISMAT, Caen (France); Thiaudière, Dominique [Synchrotron SOLEIL, L' Orme des Merisiers Saint-Aubin, Paris (France); Hardie, Christopher [University of Oxford, Materials Department (United Kingdom); Korsunsky, Alexander M. [University of Oxford, Dept. of Engineering Science (United Kingdom)

2013-12-31

Nanocrystalline metallic coatings of sub-micron thickness are widely used in modern microelectronic applications. In X-ray diffraction experiments to determine both the residual and applied stresses in nanocrystalline coatings, one difficult challenge that comes up invariably is the determination of the strain-free lattice spacing d{sub o}. The present study addresses this challenge by using the focused ion beam (FIB) to generate a built-in strain-free reference by patterning (milling) a 50 × 50 μm{sup 2} region of the coating to produce an array of small stress-relieved “islands” ∼ 0.8 × 0.8 μm{sup 2} each. Transmission X-ray diffraction setup was used for data collection at DIFFABS beamline (Synchrotron SOLEIL, France). A 150 nm-thick multi-layered W–Cu nano-composite thin film on polyimide (Kapton®) substrate was studied. The samples were loaded incrementally using a compact uniaxial loading device, and micro-beam diffraction data were collected on and away from the reference array. It was shown experimentally that the “island” array remained approximately strain free throughout the experiment, providing an on-board d{sub o} lattice spacing reference. The changing lattice spacing d in the coating was also monitored away from the array, to deduce the elastic strain evolution during deformation. The results and their implications are presented and discussed. - Highlights: • In situ deformation study of laminate polycrystalline W–Cu thin films • Focused ion beam (FIB) patterning of an array of “islands” on thin films surface • X-ray diffraction on island-patterned region • Constant strain on “islands” independently of the deformation of the substrate.

Structure and optical properties of [In{sub 1−2x}Sn{sub x}Zn{sub x}]GaO{sub 3}(ZnO){sub m}

Energy Technology Data Exchange (ETDEWEB)

Eichhorn, Simon; Mader, Werner, E-mail: mader@uni-bonn.de

2016-01-15

Compounds of [In{sub 1−2x}Sn{sub x}Zn{sub x}]GaO{sub 3}(ZnO){sub 1} (x≤0.22) and [In{sub 1−2x}Sn{sub x}Zn{sub x}]GaO{sub 3}(ZnO){sub 2} (x≤0.42) were prepared by solid state processing proving a substantial solid solution of Sn in the layered compounds InGaO{sub 3}(ZnO){sub m} (m=1, 2). Single crystal X-ray diffraction of the compounds reveals two In{sup 3+} ions to be substituted by one Sn{sup 4+} and one Zn{sup 2+} at the octahedral layer preserving the average charge of +3 at these sites. The substitution does not lead to an ordering of the ions but proves for the first time that the octahedral site can be occupied by different ions while all characteristics of the layered structures remain unchanged. Consequences of indium substitution are (i) decrease of the a axis compared to InGaO{sub 3}(ZnO){sub m} according to smaller ionic radii of Sn{sup 4+} and Zn{sup 2+} compared to In{sup 3+} and (ii) shift of the optical band gap to higher energies shown by UV–vis measurements. - Graphical abstract: Substitution limits of indium in InGaO{sub 3}(ZnO){sub m} (IGZO) by Sn and Zn are studied for m=1, 2 by single crystal X-ray diffraction and micro-chemical analysis. - Highlights: • New Oxides [In{sub 1−2x}Sn{sub x}Zn{sub x}]GaO{sub 3}(ZnO){sub m} (m=1, 2) with IGZO type structure. • Sn and Zn substitute for In at octahedral sites. • Crystal structures were characterized by single crystal X-ray diffraction. • Optical band gap energies were determined by UV–vis spectroscopy.

Analysis of the corium phases by X-ray diffraction; Analyses des phases du corium par diffraction des rayons X

Energy Technology Data Exchange (ETDEWEB)

Trillon, G

2004-07-01

In the framework of the severe accidents R and D studies led by CEA, the better knowledge of the corium behaviour, corium coming from the melting of a nuclear reactor, are fundamental stakes in order to master this kind of accident. Among the available physical properties of the corium, the nature of the final crystalline compounds which have been made during the, cooling gives information about its solidification and its stabilisation. X-Rays Diffraction is the reference method used in order to characterize the corium coming from the different facilities of the European platform PLINIUS of CEA-Cadarache. This work presents the scientific approach that has been followed in order to obtain information both qualitative and quantitative on corium, using X-Rays Diffraction. For instance, a specific method for identifying U{sub 1-x}Zr{sub x}O{sub 2} solid solutions has been developed, and the validity of quantitative analysis of corium crystalline phases using the Rietveld method (with an internal standard), has been tested. This last method has also permitted semi-quantitative measurements of amorphous phases within corium. For these studies, analysis of prototypical corium has been conducted on samples coming from the experiences led on the different facilities of the PLINIUS platform. These analysis allowed for the first time to obtain quantitative data of the corium crystalline phases in order to validate thermodynamic databases and has been used to estimate the thereto-physical properties of the corium. New information on crystalline phases of corium has also been found, especially for the UO{sub 2}-ZrO{sub 2} pseudo binary system. (author)

Thin film characterisation by advanced X-ray diffraction techniques

International Nuclear Information System (INIS)

Cappuccio, G.; Terranova, M.L.

1996-09-01

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

Multiple x-ray diffraction simulation and applications

International Nuclear Information System (INIS)

Costa, C.A.B.S. da.

1989-09-01

A computer program (MULTX) was implemented for simulation X-ray multiple diffraction diagrams in Renninger geometries. The program uses the X-ray multiple diffraction theory for imperfect crystals. The iterative calculation of the intensities is based on the Taylor series general term, and the primary beam power expansion is given as function of the beam x penetration in the crystal surface. This development allows to consider the simultaneous interaction of the beams involved in the multiple diffraction phenomenon. The simulated diagrams are calculated point-to-point and the tests for the Si and GaAs presented good reproduction of the experimental diagrams for different primary reflections. (L.C.J.A.)

X-ray diffraction microtomography using synchrotron radiation

CERN Document Server

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

2001-01-01

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

CCD-based X-ray detectors for X-ray diffraction studies

International Nuclear Information System (INIS)

Ito, K.; Amemiya, Y.

1999-01-01

CCD-based X-ray detectors are getting to be used for X-ray diffraction studies especially in the studies where real time (automated) measurements and time-resolved measurements are required. Principles and designs of two typical types of CCD-based detectors are described; one is ths system in which x-ray image intensifiers are coupled to maximize the detective quantum efficiency for time-resolved measurements, and the other is the system in which tapered optical fibers are coupled for the reduction of the image into the CCD, which is optimized for automated measurements for protein crystallography. These CCD-based X-ray detectors have an image distortion and non-uniformity of response to be corrected by software. Correction schemes which we have developed are also described. (author)

High-energy X-ray diffraction studies of disordered materials

International Nuclear Information System (INIS)

Kohara, Shinji; Suzuya, Kentaro

2003-01-01

With the arrival of the latest generation of synchrotron sources and the introduction of advanced insertion devices (wigglers and undulators), the high-energy (E≥50 keV) X-ray diffraction technique has become feasible, leading to new approaches in the quantitative study of the structure of disordered materials. High-energy X-ray diffraction has several advantages: higher resolution in real space due to a wide range of scattering vector Q, smaller correction terms (especially the absorption correction), reduction of truncation errors, the feasibility of running under extreme environments, including high-temperatures and high-pressures, and the ability to make direct comparisons between X-ray and neutron diffraction data. Recently, high-energy X-ray diffraction data have been combined with neutron diffraction data from a pulsed source to provide more detailed and reliable structural information than that hitherto available

X-ray diffraction diagnostic design for the National Ignition Facility

Science.gov (United States)

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

2013-09-01

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

On ternary intermetallic aurides. CaAu{sub 2}Al{sub 2}, SrAu{sub 2-x}Al{sub 2+x} and Ba{sub 3}Au{sub 5+x}Al{sub 6-x}

Energy Technology Data Exchange (ETDEWEB)

Stegemann, Frank [Institut fuer Anorganische und Analytische Chemie, Westfaelische Wilhelms-Universitaet Muenster (Germany); Benndorf, Christopher [Institut fuer Anorganische und Analytische Chemie, Westfaelische Wilhelms-Universitaet Muenster (Germany); Institut fuer Physikalische Chemie, Westfaelische Wilhelms-Universitaet Muenster (Germany); Institut fuer Mineralogie, Kristallographie und Materialwissenschaften, Universitaet Leipzig (Germany); Zhang, Yuemei; Fokwa, Boniface P.T. [Department of Chemistry, University of California, Riverside, CA (United States); Bartsch, Manfred; Zacharias, Helmut [Physikalisches Institut, Westfaelische Wilhelms-Universitaet Muenster (Germany); Eckert, Hellmut [Institut fuer Physikalische Chemie, Westfaelische Wilhelms-Universitaet Muenster (Germany); Instituto de Fisica de Sao Carlos, Universidade de Sao Paulo, Sao Carlos, SP (Brazil); Janka, Oliver [Institut fuer Anorganische und Analytische Chemie, Westfaelische Wilhelms-Universitaet Muenster (Germany); Institut fuer Chemie, Carl von Ossietzky Universitaet Oldenburg (Germany)

2017-11-17

The intermetallic compound CaAu{sub 2}Al{sub 2}, and the members of the solid solutions SrAu{sub 2-x}Al{sub 2+x} (0 ≤ x ≤ 0.33) and Ba{sub 3}Au{sub 5+x}Al{sub 6-x} (x = 0, 0.14, 0.49) were synthesized from the elements in sealed tantalum ampoules. The Ca compound crystallizes with the orthorhombic ThRu{sub 2}P{sub 2} type structure, whereas the targeted SrAu{sub 2}Al{sub 2} was found to form a solid solution according to SrAu{sub 2-x}Al{sub 2+x}. For the Ba system no ''BaAu{sub 2}Al{sub 2}'' was found, however, Ba{sub 3}Au{sub 5+x}Al{sub 6-x} was discovered to crystallize in the monoclinic space group C2/c with its own structure type. The samples were investigated by powder X-ray diffraction and their crystal structures were refined on the basis of single-crystal X-ray diffraction data. All compounds were characterized furthermore by susceptibility measurements. The crystallographic aluminum sites of CaAu{sub 2}Al{sub 2} and Ba{sub 3}Au{sub 5}Al{sub 6} can be differentiated by {sup 27}Al solid state NMR spectra on the basis of their different electric field gradients, in agreement with theoretical calculations. The electron transfer from the alkaline earth metals and the aluminum atoms onto the gold atoms was investigated by X-ray photoelectron spectroscopy (XPS) classifying these intermetallics as aurides, in full agreement with the calculated Bader charges. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Structure of Se-Te glasses studied using neutron, X-ray diffraction and reverse Monte Carlo modelling

Energy Technology Data Exchange (ETDEWEB)

Itoh, Keiji, E-mail: itoh@okayama-u.ac.jp [Graduate School of Education, Okayama University, Tsushima-naka, Okayama 700-8530 (Japan); Research Reactor Institute, Kyoto University, Kumatori, Osaka 590-0494 (Japan)

2017-02-15

Pulsed neutron diffraction and synchrotron X-ray diffraction measurements were performed on Se{sub 100-x}Te{sub x} bulk glasses with x=10, 20, 30 and 40. The coordination numbers obtained from the diffraction results demonstrate that Se and Te atoms are twofold coordinated and the glass structure is formed by the chain network. The three-dimensional structure model for Se{sub 60}Te{sub 40} glass obtained by using reverse Monte Carlo modelling shows that the alternating arrangements of Se and Te atoms compose the major part of the chain clusters but several other fragments such as Se{sub n} chains and Te-Te dimers are also present in large numbers. The chain clusters have geometrically disordered forms and the interchain atomic order is different from those in the crystal structures of trigonal Se and trigonal Te. - Graphical abstract: Coordination environment in Se{sub 60}Te{sub 40} glass.

X-ray diffraction

International Nuclear Information System (INIS)

Einstein, J.R.; Wei, C.H.

1982-01-01

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

Neutron powder diffraction investigation of magnetic structure and spin reorientation transition of HoFe{sub 1-x}Cr{sub x}O{sub 3} solid solutions

Energy Technology Data Exchange (ETDEWEB)

Liu, Xinzhi [Department of Nuclear Physics, China Institute of Atomic Energy, Beijing 102413 (China); Hao, Lijie, E-mail: haolijie@ciae.ac.cn [Department of Nuclear Physics, China Institute of Atomic Energy, Beijing 102413 (China); Liu, Yuntao; Ma, Xiaobai; Meng, Siqin; Li, Yuqing; Gao, Jianbo; Guo, Hao; Han, Wenze; Sun, Kai; Wu, Meimei [Department of Nuclear Physics, China Institute of Atomic Energy, Beijing 102413 (China); Chen, Xiping; Xie, Lei [Institute of Nuclear Physics and Chemistry, CAEP, Mianyang 621900 (China); Klose, Frank [Australian Nuclear Science and Technology Organization, Lucas Heights, New South Wales 2234 (Australia); Department of Physics and Materials Science, The City University of Hong Kong, Hong Kong (China); Chen, Dongfeng, E-mail: dongfeng@ciae.ac.cn [Department of Nuclear Physics, China Institute of Atomic Energy, Beijing 102413 (China)

2016-11-01

Orthoferrite solid solution HoFe{sub 1−x}Cr{sub x}O{sub 3} (x=0, 0.2,…,1.0) was synthesized via solid state reaction methods. The crystal structure, magnetism and spin reorientation properties of this system were investigated by X-ray diffraction, neutron powder diffraction and magnetic measurements. For compositions of x≤0.6, the system exhibits similar magnetic properties to HoFeO{sub 3}. With increasing Cr-doping, the system adopts a Γ{sub 4}(G{sub x}A{sub y}F{sub z}) magnetic configuration with a decreased Neel temperature from 640 K to 360 K. A Γ{sub 42} spin reorientation of Fe(Cr){sup 3+} was also observed in this system with an increase in transition temperature from 56 K to about 200 K due to competition between the Fe(Cr)–Fe(Cr) and Ho–Fe(Cr) interactions. For the x≥0.8, the system behaves more like HoCrO{sub 3} which adopts a Γ{sub 2}(F{sub x}C{sub y}G{sub z}) configuration with no spin reorientation below the Neel temperature T{sub N}. Throughout the whole substitution range, we found that the saturated moment of Fe(Cr) was less than the ideal value for a free ion, which implies the existence of spin fluctuation in this system. A systematic magnetic structure variation with Cr-substitution is revealed by Rietveld refinement. A phase diagram combining the results of the magnetic measurements and neutron powder diffraction results was obtained. - Highlights: • With Cr-substitution in the HoFe{sub 1−x}Cr{sub x}O{sub 3} system, A Γ{sub 42} spin reorientation of Fe(Cr){sup 3+} was observed with an increase in transition temperature from 56 K to about 200 K for x=0−0.6. • The saturated moment of Fe(Cr) position was found to be systematically less than the ideal value of free ion, and thus implies the presence of spin quantum fluctuation. • A composition–temperature phase diagram throughout x=0–1 for HoFe{sub 1−x}Cr{sub x}O{sub 3} system was established.

New structural studies of liquid crystal by reflectivity and resonant X-ray diffraction

International Nuclear Information System (INIS)

Fernandes, P.

2007-04-01

This memory presents three structural studies of smectic Liquid Crystals by reflectivity and resonant diffraction of X-rays. It is divided in five chapters. In the first a short introduction to Liquid Crystals is given. In particular, the smectic phases that are the object of this study are presented. The second chapter is consecrated to the X-ray experimental techniques that were used in this work. The three last chapters present the works on which this thesis can be divided. Chapter three demonstrates on free-standing films of MHPOBC (historic liquid crystal that possesses the antiferroelectric sub-phases) the possibility to extend the technique of resonant X-ray diffraction to liquid crystals without resonant element. In the fourth chapter the structure of the B 2 liquid crystal phase of bent-core molecules (or banana molecules) is elucidated by using resonant X-ray diffraction combined with polarization analysis of the diffracted beam. A model of the polarization of the resonant beam diffracted by four different structures proposed for the B 2 phase is developed in this chapter. In the fifth chapter a smectic binary mixture presenting a very original critical point of phase separation is studied by X-ray reflectivity and optical microscopy. A concentration gradient in the direction perpendicular to the plane of the film seems to be induced by the free-standing film geometry. The results of a simplified model of the system are compatible with this interpretation

Atomic substitution effects on the structural and vibrational properties of Ni{sub x}Pb{sub 1-x}TiO{sub 3}: X-ray diffraction and Raman scattering investigations

Energy Technology Data Exchange (ETDEWEB)

Costa, R. C. da [Universidade Federal de São Carlos, Departamento de Física, São Carlos-SP, 13565-905 (Brazil); Universidade Federal de Campina Grande, Pombal-PB, 58840-000 (Brazil); Toledo, T. A. de; Pizani, P. S., E-mail: pizani@df.ufscar.br [Universidade Federal de São Carlos, Departamento de Física, São Carlos-SP, 13565-905 (Brazil); Espinosa, J. W. M. [Universidade Federal de Goiás, Engenharia de Produção, Catalão-GO, 75704-020 (Brazil)

2015-07-15

The effects of the atomic substitution of Pb by Ni in the PbTiO{sub 3} ferroelectric perovskite on the vibrational and structural properties was studied using x-ray diffraction and Raman scattering. It was observed that for Ni concentrations between 0.0 and 0.4, there is the formation of a solid solution with reduction of the Raman wavenumber of the E(TO1) soft mode and the tetragonallity factor, which influence directly the temperature of the tetragonal ferroelectric to cubic paraelectric phase transition, the Curie temperature. For concentrations greater than 0.4, it is observed the formation of a PbTiO{sub 3} and NiTiO{sub 3} composite, denounced by the recovering of the both, tetragonallity factor and the E(TO1) soft mode wavenumber. The values of the Curie temperatures were estimated by the Raman scattering measurements for temperatures ranging from 300 to 950 K.

X-ray diffraction device comprising cooling medium connections provided on the x-ray tube

NARCIS (Netherlands)

1996-01-01

An X-ray diffraction device comprises a water-cooled X-ray tube which exhibits a line focus as well as, after rotation through 90 DEG , a point focus. Contrary to customary X-ray tubes, the cooling water is not supplied via the housing (12) in which the X-ray tube is mounted, but the cooling water

Peculiarities of section topograms for the multiple diffraction of X rays

Energy Technology Data Exchange (ETDEWEB)

Kohn, V. G., E-mail: kohnvict@yandex.ru [National Research Centre “Kurchatov Institute” (Russian Federation); Smirnova, I. A. [Russian Academy of Sciences, Institute of Solid State Physics (Russian Federation)

2016-07-15

The distortion of interference fringes on the section topograms of single crystal due to the multiple diffraction of X rays has been investigated. The cases of the 220 and 400 reflections in a silicon crystal in the form of a plate with a surface oriented normally to the [001] direction are considered both theoretically and experimentally. The same section topogram exhibits five cases of multiple diffraction at small azimuthal angles for the 400 reflection and MoK{sub α} radiation, while the topogram for the 220 reflection demonstrates two cases of multiple diffraction. All these cases correspond to different combinations of reciprocal lattice vectors. Exact theoretical calculations of section topograms for the aforementioned cases of multiple diffraction have been performed for the first time. The section topograms exhibit two different distortion regions. The distortions in the central region of the structure are fairly complex and depend strongly on the azimuthal angle. In the tails of the multiple diffraction region, there is a shift of two-beam interference fringes, which can be observed even with a laboratory X-ray source.

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

DEFF Research Database (Denmark)

Frankær, Christian Grundahl

This thesis presents thework on combining complementary X-rays techniques for studying the structures of proteins and other biomaterials, and consists of three different projects: (i) Characterization of protein powders with X-ray powder diffraction (XRPD). (ii) The combination of X-ray...... crystallography and X-ray absorption spectroscopy (XAS) applied to studying different hexameric insulin conformations. (iii) The structures of polymorphs of strontium ranelate and the distribution of strontium in bone tissue. A procedure for fast identification and verification of protein powders using XRPD...... was correction for disordered bulk-solvent, but also correction for background and optimization of unit cell parameters have to be taken into account. A sample holder was designed for collecting powder diffraction data on a standard laboratory X-ray powder diffractometer. The background was reduced by use...

Raman scattering from Ge{sub 1-x}Sn{sub x} (x ≤ 0.14) alloys

Energy Technology Data Exchange (ETDEWEB)

Navarro C, H.; Rodriguez, A. G.; Vidal, M. A. [Universidad Autonoma de San Luis Potosi, Coordinacion para la Innovacion y la Aplicacion de la Ciencia y la Tecnologia, Alvaro Obregon No. 64, 78000 San Luis Potosi, S. L. P. (Mexico); Perez Ladron de G, H. [Universidad de Guadalajara, Centro Universitario de los Lagos, Av. Enrique Diaz de Leon No. 1144, Col. Paseos de la Montana, 47460 Lagos de Moreno, Jalisco (Mexico)

2015-07-01

Ge{sub 1-x}Sn{sub x} alloys with x concentration up to 0.14 were grown on Ge(001) and GaAs(001) substrates in a conventional R. F. Magnetron Sputtering system at low substrate temperatures. The structural characteristics of these alloys were studied for different Sn concentrations between 1 to 14% by high resolution X-ray diffraction, and Raman spectroscopy. Contrasting characteristics of the grown layers are observed if the Sn concentration is larger or smaller than 6% as revealed by X-ray diffraction and Raman spectroscopy. (Author)

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

Indian Academy of Sciences (India)

the crystalline quality through full-width at half-maximum values. .... angular divergence of ∆α = 12 arc sec. X-rays generated from the monochromator were diffracted from (0 0 6) LiNbO3 atomic planes with the (+, −, −, +, +) geometry. [8].

Femtosecond X-ray diffraction from two-dimensional protein crystals

Directory of Open Access Journals (Sweden)

Matthias Frank

2014-03-01

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

Novel X-ray imaging diagnostics of high energy nanosecond pulse accelerators

International Nuclear Information System (INIS)

Smith, Graham W.; Gallegos, Roque Rosauro; Hohlfelder, Robert James; Beutler, David Eric; Dudley, John; Seymour, Calvin L.G.; Bell, John D.

2004-01-01

Pioneering x-ray imaging has been undertaken on a number of AWE's and Sandia National Laboratories radiation effects x-ray simulators. These simulators typically yield a single very short (<50ns) pulse of high-energy (MeV endpoint energy bremsstrahlung) x-ray radiation with doses in the kilorad (krad(Si)) region. X-ray source targets vary in size from 2 to 25cm diameter, dependent upon the particular simulator. Electronic imaging of the source x-ray emission under dynamic conditions yields valuable information upon how the simulator is performing. The resultant images are of interest to the simulator designer who may configure new x-ray source converter targets and diode designs. The images can provide quantitative information about machine performance during radiation effects testing of components under active conditions. The effects testing program is a valuable interface for validation of high performance computer codes and models for the radiation effects community. A novel high-energy x-ray imaging spectrometer is described whereby the spectral energy (0.1 to 2.5MeV) profile may be discerned from the digitally recorded and viewable images via a pinhole/scintillator/CCD imaging system and knowledge of the filtration parameters. Unique images, analysis and a preliminary evaluation of the capability of the spectrometer are presented. Further, a novel time resolved imaging system is described that captures a sequence of high spatial resolution temporal images, with zero interframe time, in the nanosecond timeframe, of our source x-rays.

Molecular beam epitaxy of GeTe-Sb{sub 2}Te{sub 3} phase change materials studied by X-ray diffraction

Energy Technology Data Exchange (ETDEWEB)

Shayduk, Roman

2010-05-20

The integration of phase change materials into semiconductor heterostructures may lead to the development of a new generation of high density non-volatile phase change memories. Epitaxial phase change materials allow to study the detailed structural changes during the phase transition and to determine the scaling limits of the memory. This work is dedicated to the epitaxial growth of Ge-Sb-Te phase change alloys on GaSb(001). We deposit Ge-Sb-Te (GST) films on GaSb(001) substrates by means of molecular beam epitaxy (MBE). The film orientation and lattice constant evolution is determined in real time during growth using grazing incidence X-ray diffraction (GID). The nucleation stage of the growth is studied in situ using reflection high energy electron diffraction (RHEED). Four growth regimes of GST on GaSb(001) were observed: amorphous, polycrystalline, incubated epitaxial and direct epitaxial. Amorphous film grows for substrate temperatures below 100 C. For substrate temperatures in the range 100-160 C, the film grows in polycrystalline form. Incubated epitaxial growth is observed at temperatures from 180 to 210 C. This growth regime is characterized by an initial 0.6nm thick amorphous layer formation, which crystallizes epitaxially as the film thickness increases. The determined lattice constant of the films is 6.01 A, very close to that of the metastable GST phase. The films predominantly possess an epitaxial cube-on-cube relationship. At higher temperatures the films grow epitaxially, however the growth rate is rapidly decreasing with temperature. At temperatures above 270 C the growth rate is zero. The composition of the grown films is close to 2:2:5 for Ge, Sb and Te, respectively. The determined crystal structure of the films is face centered cubic (FCC) with a rhombohedral distortion. The analysis of X-ray peak widths gives a value for the rhombohedral angle of 89.56 . We observe two types of reflections in reciprocal space indicating two FCC sublattices in

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

Energy Technology Data Exchange (ETDEWEB)

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)

2013-12-21

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.

Microbeam high-resolution diffraction and x-ray standing wave methods applied to semiconductor structures

International Nuclear Information System (INIS)

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

2004-01-01

A new approach to conditioning x-ray microbeams for high angular resolution x-ray diffraction and scattering techniques is introduced. We combined focusing optics (one-bounce imaging capillary) and post-focusing collimating optics (miniature Si(004) channel-cut crystal) to generate an x-ray microbeam with a size of 10 μm and ultimate angular resolution of 14 μrad. The microbeam was used to analyse the strain in sub-micron thick InGaAsP epitaxial layers grown on an InP(100) substrate by the selective area growth technique in narrow openings between the oxide stripes. For the structures for which the diffraction peaks from the substrate and the film overlap, the x-ray standing wave technique was applied for precise measurements of the strain with a Δd/d resolution of better than 10 -4 . (rapid communication)

Polarisation resonance in X-ray diffraction

International Nuclear Information System (INIS)

Goodman, P.; Paterson, D.; Matheson, S.

1994-01-01

The study of crystal structures by means of dynamic X-ray diffraction has placed a challenge to theoreticians to revise the X-ray diffraction theory based on Maxwell's equation. In this paper the feasibility of using 'polarisation resonance' as a tool in the determination of absolute configuration for asymmetric structures is investigated. Two (left- and right-handed), σ + and σ- , circular polarization states for 3-beam conditions are considered. Moreover, extending interaction into the 3 rd. dimension (normal to the beam) opens the possibility of absolute configuration determination of asymmetric structures in 3 dimensions. The computational scheme used is shown in terms of scattering diagrams. 7 refs., 1 tab., 6 figs

LaCu<sub>6-xAg_{x>: A promising host of an elastic quantum critical point}

Energy Technology Data Exchange (ETDEWEB)

Poudel, Lekh [ORNL; Dela Cruz, Clarina R. [ORNL; Koehler, Michael R. [University of Tennessee, Knoxville (UTK); McGuire, Michael A. [ORNL; Keppens, Veerle [University of Tennessee, Knoxville (UTK); Mandrus, David [ORNL; Christianson, Andrew D. [ORNL

2018-05-01

Structural properties of LaCu<sub>6-xAg<sub>x> have been investigated using neutron and x-ray diffraction, and resonant ultrasound spectroscopy (RUS) measurements. Diffraction measurements indicate a continuous structural transition from orthorhombic (Pnma) to monoclinic (P2₁/C) structure. RUS measurements show softening of natural frequencies at the structural transition, consistent with the elastic nature of the structural ground state. The structural transition temperatures in LaCu_6-xAg<sub>x> decrease with Ag composition until the monoclinic phase is completely suppressed at xc>=0.225. All of the evidence is consistent with the presence of an elastic quantum critical point in LaCu_6-xAgx>.

On the theory of time-resolved x-ray diffraction

DEFF Research Database (Denmark)

Henriksen, Niels Engholm; Møller, Klaus Braagaard

2008-01-01

We derive the basic theoretical formulation for X-ray diffraction with pulsed fields, using a fully quantized description of light and matter. Relevant time scales are discussed for coherent as well as incoherent X-ray pulses, and we provide expressions to be used for calculation...... of the experimental diffraction signal for both types of X-ray sources. We present a simple analysis of time-resolved X-ray scattering for direct bond breaking in diatomic molecules. This essentially analytical approach highlights the relation between the signal and the time-dependent quantum distribution...

X-ray-induced dissociation of H.sub.2O and formation of an O.sub.2-H.sub.2 alloy at high pressure

Science.gov (United States)

Mao, Ho-kwang [Washington, DC; Mao, Wendy L [Washington, DC

2011-11-29

A novel molecular alloy of O.sub.2 and H.sub.2 and a method of producing such a molecular alloy are provided. When subjected to high pressure and extensive x-radiation, H.sub.2O molecules cleaved, forming O--O and H--H bonds. In the method of the present invention, the O and H framework in ice VII was converted into a molecular alloy of O.sub.2 and H.sub.2. X-ray diffraction, x-ray Raman scattering, and optical Raman spectroscopy demonstrate that this crystalline solid differs from previously known phases.

Crystallization behavior of (1 - x)Li{sub 2}O.xNa{sub 2}O.Al{sub 2}O{sub 3}.4SiO{sub 2} glasses

Energy Technology Data Exchange (ETDEWEB)

Wang, Moo-Chin [Department of Fragrance and Cosmetic Science, Kaohsiung Medical University, 100 Shih-Chuan 1st Road, Kaohsiung 807, Taiwan (China); Cheng, Chih-Wei; Chang, Kuo-Ming [Department of Mechanical Engineering, National Kaohsiung University of Applied Sciences, 415 Chien-Kung Road, Kaohsiung 80782, Taiwan (China); Hsi, Chi-Shiung, E-mail: chsi@nuu.edu.t [Department of Materials Science and Engineering, National United University, 1 Lien-Da, Kung-Ching Li, Miao-Li 36003, Taiwan (China)

2010-07-02

The crystallization behavior of the (1 - x)Li{sub 2}O.xNa{sub 2}O.Al{sub 2}O{sub 3}.4SiO{sub 2} glasses has been investigated using X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), electron diffraction (ED) and energy dispersive spectroscopy (EDS). The crystalline phase was composed of {beta}-spodumene. The isothermal crystallization kinetics of {beta}-spodumene from the (1 - x)Li{sub 2}O.xNa{sub 2}O.Al{sub 2}O{sub 3}.4SiO{sub 2} glasses has also been studied by a quantitative X-ray diffraction method. The activation energy of {beta}-spodumene formation decreases from 359.2 to 317.8 kJ/mol when the Na{sub 2}O content increases from 0 to 0.4 mol and it increases from 317.8 to 376.9 kJ/mol when the Na{sub 2}O content increases from 0.4 to 0.6 mol. The surface nucleation and plate-like growth were dominant in the crystallization of the (1 - x)Li{sub 2}O.xNa{sub 2}O.Al{sub 2}O{sub 3}.4SiO{sub 2} glasses.

X-ray topography under conditions of monochromatic spherical wave diffraction

International Nuclear Information System (INIS)

Aristov, V.V.; Polovinkina, V.I.; Ibhikawa, Tetsuya; Kiduta, Seishi.

1981-01-01

An X-ray topographic scheme was developed in which there is a large distance between the X-ray source and the specimen. A monochromatic X-ray beam with an angular divergence 6 x 10 - 5 rad obtained by double successive diffraction in the (n 1 , +n 2 ) setting was used. This scheme enables diffraction focusing of a weakly absorbed wave field onto the exit surface of the crystal to be performed. Topographs of a wedge-shaped silicon crystal were obtained. Interference effects such as focusing, anomalous and ordinary Pendelloesung effects peculiar to X-ray spherical wave diffraction were observed in the topographs with high resolution. (author)

The phase problem and perspectives of surface X-ray diffraction

International Nuclear Information System (INIS)

Tajiri, Hiroo; Takahashi, Toshio

2009-01-01

The emergence of synchrotron radiation sources has accelerated the application of diffraction techniques to surface sciences. Surface X-ray diffraction has become the state-of-the-art technique for determining ordered structures of atoms on crystal surfaces. We introduce surface X-ray diffraction briefly from the historical point of view and describe the concept that not only determine constellation of surface atoms but also view surface atoms as image. The progress in experimental and theoretical studies of surface X-ray diffraction including crystallographic direct methods is reviewed. (author)

Synchrotron x-ray diffraction study of liquid surfaces

DEFF Research Database (Denmark)

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

1983-01-01

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

In situ defect annealing of swift heavy ion irradiated CeO<sub>2sub> and ThO<sub>2sub> using synchrotron X-ray diffraction and a hydrothermal diamond anvil cell

Energy Technology Data Exchange (ETDEWEB)

Palomares, Raul I.; Tracy, Cameron L.; Zhang, Fuxiang; Park, Changyong; Popov, Dmitry; Trautmann, Christina; Ewing, Rodney C.; Lang, Maik

2015-04-16

Hydrothermal diamond anvil cells (HDACs) provide facile means for coupling synchrotron X-ray techniques with pressure up to 10 GPa and temperature up to 1300 K. This manuscript reports on an application of the HDAC as an ambient-pressure sample environment for performingin situdefect annealing and thermal expansion studies of swift heavy ion irradiated CeO<sub>2sub>and ThO<sub>2sub>using synchrotron X-ray diffraction. The advantages of thein situHDAC technique over conventional annealing methods include rapid temperature ramping and quench times, high-resolution measurement capability, simultaneous annealing of multiple samples, and prolonged temperature and apparatus stability at high temperatures. Isochronal annealing between 300 and 1100 K revealed two-stage and one-stage defect recovery processes for irradiated CeO<sub>2sub>and ThO<sub>2sub>, respectively, indicating that the morphology of the defects produced by swift heavy ion irradiation of these two materials differs significantly. These results suggest that electronic configuration plays a major role in both the radiation-induced defect production and high-temperature defect recovery mechanisms of CeO<sub>2sub>and ThO<sub>2sub>.

X-ray diffraction and Moessbauer studies on superparamagnetic nickel ferrite (NiFe{sub 2}O{sub 4}) obtained by the proteic sol–gel method

Energy Technology Data Exchange (ETDEWEB)

Nogueira, N.A.S. [Departamento de Engenharia Metalúrgica e de Materiais, Centro de Tecnologia, Campus do Pici, Universidade Federal do Ceará – UFC, 60455-760 Fortaleza, CE (Brazil); Utuni, V.H.S.; Silva, Y.C. [Departamento de Física, Universidade Federal do Ceará – UFC, Campus do Pici, 60440-970 Fortaleza, CE (Brazil); Kiyohara, P.K. [Instituto de Física, Universidade de São Paulo – USP, 05315-970 São Paulo, SP (Brazil); Vasconcelos, I.F. [Departamento de Engenharia Metalúrgica e de Materiais, Centro de Tecnologia, Campus do Pici, Universidade Federal do Ceará – UFC, 60455-760 Fortaleza, CE (Brazil); Miranda, M.A.R., E-mail: marcus.a.r.miranda@gmail.com [Departamento de Física, Universidade Federal do Ceará – UFC, Campus do Pici, 60440-970 Fortaleza, CE (Brazil); Sasaki, J.M. [Departamento de Física, Universidade Federal do Ceará – UFC, Campus do Pici, 60440-970 Fortaleza, CE (Brazil)

2015-08-01

Nickel ferrite (NiFe{sub 2}O{sub 4}) nanoparticles were synthesized by the proteic sol–gel method at synthesis temperature of 250 °C, 300 °C and 400 °C, with the objective of obtaining superparamagnetic nanoparticles. Thermogravimetric analysis (TGA) and temperature-programed oxidation (TPO) presented peaks around 290 °C indicating that nickel ferrite was forming at this temperature. X-ray powder diffraction (XRPD) confirmed that the polycrystalline sample was single phased NiFe{sub 2}O{sub 4} with space group Fd3m. Scherrer equation applied to the diffraction patterns and transmission electron microscopy (TEM) images showed that the size of the nanoparticles ranged from 9 nm to 13 nm. TEM images also revealed that the nanoparticles were agglomerated, which was supported by the low values of surface area provided by the Brunauer-Emmet-Teller (BET) method. Moessbauer spectroscopy presented spectra composed of a superposition of three components: a sextet, a doublet and a broad singlet pattern. The sample synthetized at 300 °C had the most pronounced doublet pattern characteristic of superparamagnetic nanoparticles. In conclusion, this method was partially successful in obtaining superparamagnetic nickel ferrite nanoparticles, in which the synthetized samples were a mixture of nanoparticles with blocking temperature above and below room temperature. Magnetization curves revealed a small hysteresis, supporting the Moessbauer results. The sample with the higher concentration of superparamagnetic nanoparticles being the one synthetized at 300 °C. - Highlights: • Superparamagnetic nickel ferrite nanoparticles were grown by the proteic sol–gel method. • The proteic sol–gel method provided superparamagnetic nickel ferrite nanoparticles with sizes in the range of 9–13 nm. • Nickel ferrite nanoparticles were prepared at temperatures as low as 250 °C. • The nickel ferrite nanoparticles were studied by x-ray diffraction and Moessbauer.

Reactivity, structure and physical properties of SrCo{sub 2.5+{delta}} and La{sub 2}CoO{sub 4.0+{delta}}. In situ X-ray diffraction and neutrons study; Reactivite, structure et proprietes physiques de SrCoO{sub 2.5+{delta}} et La{sub 2}CoO{sub 4.0+{delta}}. Etude par diffraction des rayons X et des neutrons in situ

Energy Technology Data Exchange (ETDEWEB)

Le Toquin, R.

2003-11-15

This work was devoted to the study of the reactivity and more specifically the influence of the intercalated oxygen amount {delta} on the structure and physical properties of SrCoO{sub 2.5+{delta}} et La{sub 2}CoO{sub 4.0+{delta}} We controlled the oxidation level by means of reversible electrochemical red ox reaction at room temperature. Structural modifications, especially disorder, and electronic properties were studied for the first time on large orientated single crystal. In the SrCoO{sub 2.5+{delta}} system, after structural and electronic characterisation of the end phases, we studied the real structure of the brownmillerite SrCoO{sub 2.5} phase using single crystal. Moreover, we investigated structural and magnetic evolution upon red ox cycle using X-ray diffraction on 6 times twinned single crystal and in situ neutron powder diffraction. Two intermediate SrCoO{sub 2.75} and SrCoO{sub 2.82} phases have been observed. The reaction on single crystal has evidenced the evolution of domain structure. For the La{sub 2}CoO{sub 4+{delta}} system, we synthesised a large variety of single crystal with stoichiometry {delta} 0.0, 0.09, 0.12, 0.16, 0.20 and 0.25. Using single crystal X-ray and neutron diffraction, we showed a disorder-order transition of the apical and interstitial oxygen for the higher {delta} values. (author)

Hard x-ray monochromator with milli-electron volt bandwidth for high-resolution diffraction studies of diamond crystals

Energy Technology Data Exchange (ETDEWEB)

Stoupin, Stanislav; Shvyd' ko, Yuri; Shu Deming; Khachatryan, Ruben; Xiao, Xianghui; DeCarlo, Francesco; Goetze, Kurt; Roberts, Timothy; Roehrig, Christian; Deriy, Alexey [Advanced Photon Source, Argonne National Laboratory, Illinois 60439 (United States)

2012-02-15

We report on design and performance of a high-resolution x-ray monochromator with a spectral bandwidth of {Delta}E{sub X}{approx_equal} 1.5 meV, which operates at x-ray energies in the vicinity of the backscattering (Bragg) energy E{sub H} = 13.903 keV of the (008) reflection in diamond. The monochromator is utilized for high-energy-resolution diffraction characterization of diamond crystals as elements of advanced x-ray crystal optics for synchrotrons and x-ray free-electron lasers. The monochromator and the related controls are made portable such that they can be installed and operated at any appropriate synchrotron beamline equipped with a pre-monochromator.

Time-resolved materials science opportunities using synchrotron x-ray sources

International Nuclear Information System (INIS)

Larson, B.C.; Tischler, J.Z.

1995-06-01

The high brightness, high intensity, and pulsed time-structure of synchrotron sources provide new opportunities for time-resolved x-ray diffraction investigations. With third generation synchrotron sources coming on line, high brilliance and high brightness are now available in x-ray beams with the highest flux. In addition to the high average flux, the instantaneous flux available in synchrotron beams is greatly enhanced by the pulsed time structure, which consists of short bursts of x-rays that are separated by ∼tens to hundreds of nanoseconds. Time-resolved one- and two-dimensional position sensitive detection techniques that take advantage of synchrotron radiation for materials science x-ray diffraction investigations are presented, and time resolved materials science applications are discussed in terms of recent diffraction and spectroscopy results and materials research opportunities

Diffraction enhanced kinetic depth X-ray imaging

Science.gov (United States)

Dicken, A.

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

X-ray diffraction study of the Y{sub 2}Ti{sub 2}O{sub 7} pyrochlore disordering sequence under irradiation

Energy Technology Data Exchange (ETDEWEB)

Soulié, Aurélien, E-mail: aurelien.soulie@cea.fr [CEA, DEN, Service de Recherches de Métallurgie Physique, Université Paris-Saclay, F-91191 Gif sur Yvette (France); CEA, DEN, Service de Recherches de Métallurgie Appliqué, Université Paris-Saclay, F-91191 Gif sur Yvette (France); Menut, Denis [CEA, DEN, Service de Recherches de Métallurgie Appliqué, Université Paris-Saclay, F-91191 Gif sur Yvette (France); Crocombette, Jean-Paul [CEA, DEN, Service de Recherches de Métallurgie Physique, Université Paris-Saclay, F-91191 Gif sur Yvette (France); Chartier, Alain [CEA, DEN, Service de la Corrosion et du Comportement des Matériaux dans leur Environnement, Laboratoire de Modélisation, de Thermodynamique et de Thermochimie, Université Paris-Saclay, F-91191 Gif sur Yvette (France); Sellami, Neila [Univ. Paris Sud, ICMMO-SP2M, Bât. 410, F-91405 Orsay (France); Sattonnay, Gaël [Univ. Paris-Sud, CSNSM, CNRS, IN2P3, Bât. 108, F-91405 Orsay (France); Monnet, Isabelle [CIMAP, CEA, CNRS, Université de Caen, BP 5133, F-14070 Caen Cedex 5 (France); and others

2016-11-15

The disordering sequence of Y{sub 2}Ti{sub 2}O{sub 7} pyrochlore, a nano-oxide phase that strengthens ODS steels under irradiation is studied in the experimental and modeling framework. XRD analysis has been performed considering both swift heavy ion and low energy/low mass ion irradiations. The simulation within molecular dynamics of Frenkel pair accumulation proves able to reproduce the variation of the amorphization fluence with temperature. XRD patterns calculated from the simulations reproduce well the patterns observed experimentally in the literature. Both experiments and calculations point to a first transition from pyrochlore to fluorite before an eventual amorphization. For swift heavy ion irradiations with 93 MeV Xe ions, tracks of direct impact amorphization are visible by HRTEM. Advanced refinement shows that one third of the pyrochlore impacted by an ion transforms into fluorite, while two third are directly amorphized. - Highlights: • A comparison between swift heavy ion and low energy/low mass ion irradiation of Y{sub 2}Ti{sub 2}O{sub 7} pyrochlore is performed. • Simulations of the irradiation with Molecular dynamics reproduce the amorphization dose at low energy/mass ion irradiation. • Advanced refinement of X-ray diffraction patterns gives the evolution of phase fractions in pyrochlore under irradiation. • The disordering sequence a transition from pyrochlore to defect fluorite before an eventual amorphization.

Neutron structural studies of La{sub 3.5-x-y}(Y){sub y}Ba{sub 3.5-x}Ca{sub 2x}Cu{sub 7}O{sub z} (x = y = 0.0 and 0.5) system

Energy Technology Data Exchange (ETDEWEB)

Subbarao, M V; Kulkarni, R G [Department of Physics, Saurashtra University, Rajkot (India); Rajagopal, H; Sequeira, A S [Solid State Physics Division, Bhabha Atomic Research Centre, Mumbai (India)

1997-07-01

By mixing equal amounts of La{sub 4-x}Ca{sub x}Ba{sub 3}Cu{sub 7}O{sub z} and La{sub 3}Ba{sub 4-x} Ca{sub x}Cu{sub 7}O{sub z} in the proportion of 1 : 1, a series of superconductors part of La replaced by Y with the nominal composition of La{sub 3.5-x-y}(Y){sub y} Ba{sub 3.-5-x}Ca{sub 2x}Cu{sub 7}O{sub z} (LYCP) have been prepared. Two samples with x = y = 0.0 (A) and x = y = 0.5 (B) characterized by x-ray diffraction display tetragonal triple perovskite structure. In order to investigate the effect of substituents (Ca/Y) on structure of this system, neutron diffraction measurements have been carried out at 300 K and {lambda}{sub n}=1.216A at Dhruva reactor.

LCP crystallization and X-ray diffraction analysis of VcmN, a MATE transporter from Vibrio cholerae

Energy Technology Data Exchange (ETDEWEB)

Kusakizako, Tsukasa [Graduate School of Science, The University of Tokyo, 2-11-16 Yayoi, Bunkyo-ku, Tokyo 113-0032 (Japan); Tanaka, Yoshiki [Graduate School of Biological Sciences, Nara Institute of Science and Technology, 8916-5 Takayama-cho, Ikoma, Nara 630-0192 (Japan); Hipolito, Christopher J. [Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan); University of Tsukuba, 1-1-1 Tennodai, Tsukuba 305-8575 (Japan); Kuroda, Teruo [Graduate School of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8553 (Japan); Ishitani, Ryuichiro [Graduate School of Science, The University of Tokyo, 2-11-16 Yayoi, Bunkyo-ku, Tokyo 113-0032 (Japan); Suga, Hiroaki [Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan); Nureki, Osamu, E-mail: nureki@bs.s.u-tokyo.ac.jp [Graduate School of Science, The University of Tokyo, 2-11-16 Yayoi, Bunkyo-ku, Tokyo 113-0032 (Japan)

2016-06-22

A V. cholerae MATE transporter was crystallized using the lipidic cubic phase (LCP) method. X-ray diffraction data sets were collected from single crystals obtained in a sandwich plate and a sitting-drop plate to resolutions of 2.5 and 2.2 Å, respectively. Multidrug and toxic compound extrusion (MATE) transporters, one of the multidrug exporter families, efflux xenobiotics towards the extracellular side of the membrane. Since MATE transporters expressed in bacterial pathogens contribute to multidrug resistance, they are important therapeutic targets. Here, a MATE-transporter homologue from Vibrio cholerae, VcmN, was overexpressed in Escherichia coli, purified and crystallized in lipidic cubic phase (LCP). X-ray diffraction data were collected to 2.5 Å resolution from a single crystal obtained in a sandwich plate. The crystal belonged to space group P2{sub 1}2{sub 1}2{sub 1}, with unit-cell parameters a = 52.3, b = 93.7, c = 100.2 Å. As a result of further LCP crystallization trials, crystals of larger size were obtained using sitting-drop plates. X-ray diffraction data were collected to 2.2 Å resolution from a single crystal obtained in a sitting-drop plate. The crystal belonged to space group P2{sub 1}2{sub 1}2{sub 1}, with unit-cell parameters a = 61.9, b = 91.8, c = 100.9 Å. The present work provides valuable insights into the atomic resolution structure determination of membrane transporters.

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

Energy Technology Data Exchange (ETDEWEB)

Paszkowicz, W., E-mail: paszk@ifpan.edu.pl [Institute of Physics, Polish Academy of Sciences, al. Lotnikow 32/46, PL-02668 Warsaw (Poland); Romanowski, P.; Bak-Misiuk, J. [Institute of Physics, Polish Academy of Sciences, al. Lotnikow 32/46, PL-02668 Warsaw (Poland); Wierzchowski, W. [Institute of Electronic Materials Technology, Wolczynska 133, PL-01919 Warsaw (Poland); Wieteska, K. [Institute of Atomic Energy POLATOM, PL-05400 Otwock-Swierk (Poland); Graeff, W. [HASYLAB at DESY, Notkestr. 85, D-22603 Hamburg (Germany); Iwanowski, R.J. [Institute of Physics, Polish Academy of Sciences, al. Lotnikow 32/46, PL-02668 Warsaw (Poland); Heinonen, M.H. [Laboratory of Materials Science, Department of Physics, University of Turku, Vesilinnantie 5, FI-20014, Turku (Finland); Ermakova, O. [Institute of Physics, Polish Academy of Sciences, al. Lotnikow 32/46, PL-02668 Warsaw (Poland); Dabkowska, H. [Department of Physics, McMaster University, Hamilton, Ontario, L8S 4M1 (Canada)

2011-10-15

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

Coherent X-ray diffraction studies of mesoscopic materials

International Nuclear Information System (INIS)

Shabalin, Anatoly

2015-12-01

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

X-ray diffraction microstructural analysis of bimodal size distribution MgO nano powder

International Nuclear Information System (INIS)

Suminar Pratapa; Budi Hartono

2009-01-01

Investigation on the characteristics of x-ray diffraction data for MgO powdered mixture of nano and sub-nano particles has been carried out to reveal the crystallite-size-related microstructural information. The MgO powders were prepared by co-precipitation method followed by heat treatment at 500 degree Celsius and 1200 degree Celsius for 1 hour, being the difference in the temperature was to obtain two powders with distinct crystallite size and size-distribution. The powders were then blended in air to give the presumably bimodal-size- distribution MgO nano powder. High-quality laboratory X-ray diffraction data for the powders were collected and then analysed using Rietveld-based MAUD software using the lognormal size distribution. Results show that the single-mode powders exhibit spherical crystallite size (R) of 20(1) nm and 160(1) nm for the 500 degree Celsius and 1200 degree Celsius data respectively with the nano metric powder displays narrower crystallite size distribution character, indicated by lognormal dispersion parameter of 0.21 as compared to 0.01 for the sub-nano metric powder. The mixture exhibits relatively more asymmetric peak broadening. Analysing the x-ray diffraction data for the latter specimen using single phase approach give unrealistic results. Introducing two phase models for the double-phase mixture to accommodate the bimodal-size-distribution characteristics give R = 100(6) and σ = 0.62 for the nano metric phase and R = 170(5) and σ= 0.12 for the σ sub-nano metric phase. (author)

Cation distribution and crystallographic characterization of the spinel oxides MgCr{sub x}Fe{sub 2−x}O{sub 4} by neutron diffraction

Energy Technology Data Exchange (ETDEWEB)

Zakaria, A.K.M., E-mail: zakaria6403@yahoo.com [Institute of Nuclear Science & Technology, Bangladesh Atomic Energy Commission, Dhaka (Bangladesh); Nesa, Faizun [Department of Natural Science, Daffodil International University, Dhaka (Bangladesh); Department of Physics, Jahangirnagar University, Savar, Dhaka (Bangladesh); Saeed Khan, M.A. [Department of Physics, Jahangirnagar University, Savar, Dhaka (Bangladesh); Datta, T.K.; Aktar, Sanjida; Liba, Samia Islam; Hossain, Shahzad; Das, A.K.; Kamal, I.; Yunus, S.M. [Institute of Nuclear Science & Technology, Bangladesh Atomic Energy Commission, Dhaka (Bangladesh); Eriksson, S.-G. [Department of Chemical and Biological Engineering, Chalmers University of Technology, Gothenburg (Sweden)

2015-06-05

Highlights: • MgCr{sub x}Fe{sub 2−x}O{sub 4} ferrites crystallize at 1300 °C and possess cubic symmetry. • Cation distribution and crystallographic parameters have been determined precisely. • Cell parameter decreases with increasing Cr content in the system. • Ferrimagnetic ordering was found at room temperature for all the samples. - Abstract: The spinel system MgCr{sub x}Fe{sub 2−x}O{sub 4} (x = 0.0, 0.2, 0.4, 0.6, 0.8 and 1.0) has been prepared by solid state sintering method in air at 1573 K. X-ray and neutron powder diffraction experiments have been performed on the samples at room temperature for structural characterization. Rietveld refinement of the neutron diffraction data reveals that all the samples of the series possess cubic symmetry corresponding to the space group F d-3m. The distribution of the three cations Mg, Fe and Cr over the two sublattices and other crystallographic parameters has been determined precisely. The results reveal that Cr has been substituted for Fe selectively. Cr ions invariably occupy the octahedral (B) site for all values of x. Mg and Fe ions are distributed over both A and B sites for all x values. With increasing x the occupation of Mg increases in the A site and decreases in the B site for all the samples, while the Fe ions gradually decreases in both the sites for all values of x. The lattice constant decreases with increasing Cr content in the system. The magnetic structure at room temperature was ferrimagnetic for all the samples.

X-ray streak and framing camera techniques

International Nuclear Information System (INIS)

Coleman, L.W.; Attwood, D.T.

1975-01-01

This paper reviews recent developments and applications of ultrafast diagnostic techniques for x-ray measurements. These techniques, based on applications of image converter devices, are already capable of significantly important resolution capabilities. Techniques capable of time resolution in the sub-nanosecond regime are being considered. Mechanical cameras are excluded from considerations as are devices using phosphors or fluors as x-ray converters

Brillouin scattering, DSC, dielectric and X-ray diffraction studies of phase transitions in antiferroelectric PbHfO{sub 3}:Sn

Energy Technology Data Exchange (ETDEWEB)

Mączka, Mirosław, E-mail: m.maczka@int.pan.wroc.pl [Institute of Low Temperature and Structure Research, Polish Academy of Sciences, P.O. Box 1410, 50-950 Wrocław 2 (Poland); Kim, Tae Hyun [Institute of Materials Science, University of Tsukuba, Tsukuba, Ibaraki 305-8573 (Japan); Gągor, Anna [Institute of Low Temperature and Structure Research, Polish Academy of Sciences, P.O. Box 1410, 50-950 Wrocław 2 (Poland); Jankowska-Sumara, Irena [Institute of Physics, Pedagogical University, ul. Podchorążych 2, 30-084 Kraków (Poland); Majchrowski, Andrzej [Institute of Applied Physics, Military University of Technology, 2 Kaliskiego Str., 00-908 Warszawa (Poland); Kojima, Seiji [Institute of Materials Science, University of Tsukuba, Tsukuba, Ibaraki 305-8573 (Japan)

2015-02-15

Highlights: • Phase transition mechanisms were studied in antiferroelectric PbHf{sub 0.975}Sn{sub 0.025}O{sub 3.} • Acoustic phonons showed anomalies at 472 and 426 K due to phase transitions. • Brillouin data showed evidence for presence of polar clusters in paraelectric phase. • An order-disorder mechanism of the PE to AFE2 transition was proved. - Abstract: Specific heat, dielectric, powder X-ray diffraction and Brillouin scattering studies of phase transitions in antiferroelectric PbHf{sub 0.975}Sn{sub 0.025}O{sub 3} crystal were performed. The specific heat data revealed clear anomalies at T{sub 1} = 473.5 and T{sub 2} = 426.3 K on cooling, which could be attributed to onset of first order phase transitions from the paraelectric (PE) phase to an intermediate antiferroelectric phase (AFE2) and the AFE2 phase to another antiferroelectric phase (AFE1), respectively. The estimated entropy changes at T{sub 1} and T{sub 2} pointed to mainly an order-disorder and displacive character of these transitions, respectively. X-ray diffraction data showed a complex superstructure of the intermediate phase with a = 11.895(6) Å, b = 11.936(4) Å, c = 8.223(3) Å at 453 K. Brillouin studies revealed pronounced softening of longitudinal acoustic (LA) mode in the PE phase associated with its broadening. The broadening and softening exhibited maximum values at T{sub 1}. Additional acoustic anomalies, that is, abrupt frequency shifts for LA and transverse acoustic (TA) modes were also observed at T{sub 2}. Brillouin scattering data also showed presence of a broad central peak (CP) that exhibited highest intensity at T{sub 1}. The observed temperature dependences of acoustic modes and CP indicate order-disorder character of the FE to AFE2 phase transition and importance of polar precursor clusters in the PE phase. The obtained data also suggest that the intermediate antiferroelectric phases in Sn{sup 4+} doped PbHfO{sub 3} and PbZrO{sub 3} may have very similar structures

X-ray diffraction

International Nuclear Information System (INIS)

Vries, J.L. de.

1976-01-01

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

X-ray diffraction and X-ray standing-wave study of the lead stearate film structure

Energy Technology Data Exchange (ETDEWEB)

Blagov, A. E.; Dyakova, Yu. A.; Kovalchuk, M. V.; Kohn, V. G.; Marchenkova, M. A.; Pisarevskiy, Yu. V.; Prosekov, P. A., E-mail: prosekov@crys.ras.ru [Russian Academy of Sciences, Shubnikov Institute of Crystallography (Russian Federation)

2016-05-15

A new approach to the study of the structural quality of crystals is proposed. It is based on the use of X-ray standing-wave method without measuring secondary processes and considers the multiwave interaction of diffraction reflections corresponding to different harmonics of the same crystallographic reflection. A theory of multiwave X-ray diffraction is developed to calculate the rocking curves in the X-ray diffraction scheme under consideration for a long-period quasi-one-dimensional crystal. This phase-sensitive method is used to study the structure of a multilayer lead stearate film on a silicon substrate. Some specific structural features are revealed for the surface layer of the thin film, which are most likely due to the tilt of the upper layer molecules with respect to the external normal to the film surface.

A neutron diffraction study of the superionic transition in (Ca sub 1 sub - sub x Y sub x)F sub 2 sub + sub x with x=0.06

CERN Document Server

Hofmann, M; Wilson, C C; McIntyre, G J

1997-01-01

We have investigated the high-temperature superionic transition of the anion-excess fluorite (Ca sub 1 sub - sub x Y sub x)F sub 2 sub + sub x with x=0.06 using both monochromatic and time-of-flight Laue single-crystal neutron diffraction. The measured Bragg intensities indicate that the cuboctahedral defect clusters found at ambient temperature start to break up into smaller fragments even below the superionic transition temperature, T sub c approx 1200 K. Information concerning the local defect configuration at T = 1173 K has been provided by modelling the measured distribution of the coherent elastic diffuse scattering within the (11-bar0) plane of reciprocal space. The high-temperature defects are of the 'Willis' type and strongly resemble the short-lived Frenkel clusters found in the pure fluorites such as CaF sub 2 above T sub c. (author)

Preparation of specimens for analysis by: X-ray diffraction and X-ray fluorescence analysis

International Nuclear Information System (INIS)

Banos L, L.

2004-01-01

Specimen preparation is one of the most important requirements in the analysis of samples by X-ray Diffraction and X-ray Fluorescence. This statement is especially true for samples containing different types of materials. There are many forms of specimen suitable for X-ray analysis and the type of the sample as received will generally determine the method of pretreatment. It is convenient to refer to the material received for analysis as the sample, and that, which is actually analyzed as the specimen. The powder Diffraction method assumes that the particles in the specimen are ideally random orientation and that there are enough crystallites in the specimen to achieve a representative intensity distribution for these crystallites. X ray Fluorescence is essentially a comparative method of analysis, it is vital that all standards and unknowns be presented to the spectrometer in a reproducible and identical manner. (Author) 3 refs., 6 figs

X-ray diffraction analysis of the phase transition orthorhombic-tetragonal in Y(1-x)Ca(x)Ba2Cu3O(7) superconductors dependent on the oxygen pressure at 500 and 600deg C. Etude de la transition orthorhombique-tetragonale dans les supraconducteurs Y sub 1-x Ca sub x Ba sub 2 Cu sub 3 O sub z par diffraction des rayons X en fonction de la pression d'oxygene a 500 et 600deg C

Energy Technology Data Exchange (ETDEWEB)

Touzelin, B [Lab. C.N.S., Chimie Generale, Univ. Paris 11, 91 - Orsay (France)

1991-04-15

The oxygen partial pressures and the oxygen composition z dependence of the lattice parameters of Y{sub 1-x}Ca{sub x}Ba{sub 2}Cu{sub 3}O{sub z} have been investigated by X-ray diffraction at 500 and 600deg C for 10%, 20% and 30% calcium content. The coexistence of the orthorhombic and tetragonal phases is observed in an oxygen composition range which decreases with increasing calcium content. The tetragonal phase occurs alone at the same oxygen content: z=6.745 in a temperature range of approximately 100deg C whatever the calcium content. Its structural transition will be first order with no second order at all, as undoped 1-2-3. Lastly it is noticed that the superconductivity is independent of the structural O-T transition. (orig.).

X-ray diffraction 2 - diffraction principles

International Nuclear Information System (INIS)

O'Connor, B.

1999-01-01

Full text: The computation of powder diffraction intensities is based on the principle that the powder pattern comprises the summation of the intensity contributions from each of the crystallites (or single crystals) in the material. Therefore, it is of value for powder diffractionists to appreciate the form of the expression for calculating single crystal diffraction pattern intensities. This knowledge is especially important for Rietveld analysis practitioners in terms of the (i) mathematics of the method and (ii) retrieving single crystal structure data from the literature. We consider the integrated intensity from a small single crystal being rotated at velocity ω through the Bragg angle θ for reflection (hkl).... I(hkl) = [l o /ω]. [e 4 /m 2 c 4 ]. [λ 3 δV F(hkl) 2 /υ 2 ].[(1+cos 2 2θ)/2sin2θ] where e, m and c are the usual fundamental constants; λ is the x-ray wavelength, δV is the crystallite volume; F(hkl) is the structure factor; υ is the unit cell volume; and (1+cos 2 θ)/2sin2θ] is the Lorentz-polarisation factor for an unpolarised incident beam. The expression does not include a contribution for extinction. The influence of factors λ, δV, F(hkl) and υ on the intensities should be appreciated by powder diffractionists, especially the structure factor, F(hkl), which is responsible for the fingerprint nature of diffraction patterns, such as the rise and fall of intensity from peak to peak. The structure factor expression represents the summation of the scattered waves from each of the j scattering centres (i e atoms) in the unit cell: F(hkl) Σ f j exp[2πi (h.x j +k.y i +l. z i )] T j . Symbol f is the scattering factor (representing the atom-type scattering efficiency); (x, y, z) are the fractional position coordinates of atom j within the unit cell; and T is the thermal vibration factor for the atom given by: T j = 8π 2 2 > sin 2 θ/λ 2 with 2 > being the mean-square vibration amplitude of the atom (assumed to be isotropic). The

Three-dimensional visualization of a human chromosome using coherent x-ray diffraction

International Nuclear Information System (INIS)

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

2010-01-01

We succeeded in observing a human chromosome in two- and three-dimensions using x-ray diffraction microscopy. X-ray diffraction microscopy is a lens-less imaging technique utilizing coherent x-ray diffraction, and can overcome various limitations in conventional lens-based x-ray microscopy. Biological applications of the method have been limited to 2D observation, and 3D observation has been long waited. We found that the reconstructed chromosome images contain high-density axial structure, which has not been observed under unstained or unlabeled conditions. The result experimentally demonstrates the effectiveness of x-ray diffraction microscopy in observing internal structures of unstained biological samples with high image contrast. (author)

Intensity of diffracted X-rays from biomolecules with radiation damage caused by strong X-ray pulses

International Nuclear Information System (INIS)

Kai, Takeshi; Tokuhisa, Atsushi; Moribayashi, Kengo; Fukuda, Yuji; Kono, Hidetoshi; Go, Nobuhiro

2014-01-01

In order to realize the coherent X-ray diffractive imaging of single biomolecules, the diffraction intensities, per effective pixel of a single biomolecule with radiation damage, caused by irradiation using a strong coherent X-ray pulse, were examined. A parameter survey was carried out for various experimental conditions, using a developed simulation program that considers the effect of electric field ionization, which was slightly reported on in previous studies. The two simple relationships among the parameters were identified as follows: (1) the diffraction intensity of a biomolecule slightly increases with the incident X-ray energy; and that (2) the diffraction intensity is approximately proportional to the target radius, when the radius is longer than 400 Å, since the upper limit of the incident intensity for damage to the biomolecules marginally changes with respect to the target radius. (author)

Magnetic behavior of the alloys (Ce{sub 1-x}Y{sub x}){sub 2}PdSi{sub 3}

Energy Technology Data Exchange (ETDEWEB)

Mallik, R [Tata Inst. of Fundamental Res., Colaba, Mumbai (India); Sampathkumaran, E V [Tata Inst. of Fundamental Res., Colaba, Mumbai (India)

1996-11-01

The results of X-ray diffraction (Cu K{sub {alpha}}), electrical resistivity ({rho}), heat capacity (C) and magnetic susceptibility ({chi}) measurements are reported for a new pseudoternary solid solution, (Ce{sub 1-x}Y{sub x}){sub 2}PdSi{sub 3} (x=0.0, 0.2, 0.5, 0.8, 1.0). The X-ray diffraction patterns indicate that single phase alloys can be formed in a derived version of the AlB{sub 2}-type hexagonal structure for x{>=}0.2, while for x=0.0, apparently there is an additional weak phase. In the case of the alloy Ce{sub 2}PdSi{sub 3}, the majority of Ce ions do not exhibit magnetic ordering down to 1.4 K, though magnetic ordering at 7 K from one of the two crystallographically inequivalent sites cannot be ruled out. For other compositions, no magnetic ordering is observed above 1.4 K. The Kondo effect is operative in all these alloys, with the strength of the Kondo effect increasing with the compression of the lattice by the gradual replacement of Ce by Y. The C/T exhibits a low temperature enhancement in all Ce containing alloys. (orig.).

Extended X-ray absorption fine structure and X-ray diffraction studies on supported Ni catalysts

International Nuclear Information System (INIS)

Aldea, N.; Marginean, P.; Yaning, Xie; Tiandou, Hu; Tao, Liu; Wu, Zhongua; ZhenYa, Dai

1999-01-01

In the first part of this paper, we present a study based on EXAFS spectroscopy. This method can yield structural information about the local environment around a specific atomic constituent in the amorphous materials, the location and chemical state of any catalytic atom on any support or point defect structures, in alloys and composites. EXAFS is a specific technique of the scattering of X-ray on materials. The present study is aimed toward elucidation of the local structure of Ni atoms and their interaction with oxide support. The second goal of the paper consists in X-ray diffraction on the same samples. X-ray diffraction method that is capable to determine average particle size, microstrains, probability of faults as well as particle size distribution function of supported Ni catalysts is presented. The method is based on the Fourier analysis of a single X-Ray diffraction profile. The results obtained on supported nickel catalysts, which are used in H/D isotopic exchange reactions are reported. The global structure is obtained with a new fitting method based on the Generalised Fermi Function facilities for approximation and Fourier transform of the experimental X-Ray line profiles. Both types of measurements were performed on Beijing Synchrotron Radiation Facilities (BSRF). (authors)

A high resolution position sensitive X-ray MWPC for small angle X-ray diffraction

International Nuclear Information System (INIS)

Bateman, J.E.; Connolly, J.F.; Stephenson, R.; Tappern, G.J.

1981-02-01

A small sealed-off delay line readout MWPC X-ray detector has been designed and built for small angle X-ray diffraction applications. Featuring a sensitive area of 100 mm x 25 mm it yields a spatial resolution of 0.13 mm (standard deviation) with a high rate capability and good quantum efficiency for copper K radiation. (author)

Theory of time-resolved inelastic x-ray diffraction

DEFF Research Database (Denmark)

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

2010-01-01

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

Forge: a short pulse x-ray diagnostic development facility

International Nuclear Information System (INIS)

Stradling, G.L.; Hurry, T.R.; Denbow, E.R.; Selph, M.M.; Ameduri, F.P.

1985-01-01

A new short pulse x-ray calibration facility has been brought on line at Los Alamos. This facility is being used for the development, testing and calibration of fast x-ray diagnostic systems. The x-ray source consists of a moderate size, sub-nanosecond laser focused at high intensity on an appropriate target material to generate short pulses of x-ray emission from the resulting plasma. Dynamic performance parameters of fast x-ray diagnostic instruments, such as x-ray streak cameras, can be conveniently measured using this facility

Synchrotron diffraction characterization of nanostructured KY{sub 3}F{sub 10}:Tb

Energy Technology Data Exchange (ETDEWEB)

Ichikawa, Rodrigo U.; Teixeira, Maria I.; Ranieri, Izilda M.; Martinez, Luis G., E-mail: ichikawa@usp.br, E-mail: miteixeira@ipen.br, E-mail: iranieri@ipen.br, E-mail: lgallego@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Linhares, Horacio M.S.M.D., E-mail: horacio_marconi@yahoo.com.br [Universidade Federal Fluminense (INFES/UFF), Santo Antonio de Padua, RJ (Brazil); Turrillas, Xavier, E-mail: turrillas@gmail.com [Institut de Ciència de Materials de Barcelona (ICMAB/CSIC), Dept. of Crystallography, Bellaterra (Spain)

2015-07-01

Nanostructured rare-earth fluorides materials are being intensively studied recently due to their potential applications in high-dose dosimetry. Particularly, nanostructured Tb-doped KY{sub 3}F{sub 10} has shown satisfactory results to be used in this area. In the present work, the structure and microstructure of KY{sub 3}F{sub 10}:Tb was investigated by means of X-ray synchrotron diffraction. One of the samples was analyzed as synthesized and another after a heat treatment. Rietveld refinement of synchrotron diffraction data was applied to obtain cell parameters, atomic positions and atomic displacement factors and the results were compared to values found in literature. X-ray line profile analysis methods were applied to determine mean crystallite sizes and their distribution. (author)

Surface and interface strains studied by x-ray diffraction

International Nuclear Information System (INIS)

Akimoto, Koichi; Emoto, Takashi; Ichimiya, Ayahiko

1998-01-01

The authors have developed a technique of X-ray diffraction in order to measure strain fields near semiconductor surface and interface. The diffraction geometry is using the extremely asymmetric Bragg-case bulk reflection of a small incident angle to the surface and a large angle exiting from the surface. The incident angle of the X-rays is set near critical angle of total reflection by tuning X-ray energy of synchrotron radiation at the Photon Factory, Japan. For thermally grown-silicon oxide/Si(100) interface, the X-ray intensity of the silicon substrate 311 reflection has been measured. From comparison of the full width at half maxima (FWHM) of X-ray rocking curves of various thickness of silicon oxides, it has been revealed that silicon substrate lattice is highly strained in the thin (less than about 5 nm) silicon oxide/silicon system. In order to know the original silicon surface strain, the authors have also performed the same kind of measurements in the ultra-high vacuum chamber. A clean Si(111) 7x7 surface gives sharper X-ray diffraction peak than that of the native oxide/Si(111) system. From these measurements, it is concluded that the thin silicon oxide film itself gives strong strain fields to the silicon substrates, which may be the reason of the existence of the structural transition layer at the silicon oxide/Si interface

X-ray diffraction imaging of biological cells

CERN Document Server

Nakasako, Masayoshi

2018-01-01

In this book, the author describes the development of the experimental diffraction setup and structural analysis of non-crystalline particles from material science and biology. Recent advances in X-ray free electron laser (XFEL)-coherent X-ray diffraction imaging (CXDI) experiments allow for the structural analysis of non-crystalline particles to a resolution of 7 nm, and to a resolution of 20 nm for biological materials. Now XFEL-CXDI marks the dawn of a new era in structural analys of non-crystalline particles with dimensions larger than 100 nm, which was quite impossible in the 20th century. To conduct CXDI experiments in both synchrotron and XFEL facilities, the author has developed apparatuses, named KOTOBUKI-1 and TAKASAGO-6 for cryogenic diffraction experiments on frozen-hydrated non-crystalline particles at around 66 K. At the synchrotron facility, cryogenic diffraction experiments dramatically reduce radiation damage of specimen particles and allow tomography CXDI experiments. In addition, in XFEL ex...

Comparative study of perovskite Pr{sub (1-x)}Ca{sub x}CoO{sub 3} e Gd{sub (1-x)}Ca{sub x}CoO{sub 3} (x=0,2) synthesized by gelatin modified route for application in automotive catalysis; Estudo comparativo das perovsquitas Pr{sub (1-x)}Ca{sub x}CoO{sub 3} e Gd{sub (1-x)}Ca{sub x}CoO{sub 3} (x=0,2) sintetizadas pela rota modificada gelatina para aplicacao em catalise automotiva

Energy Technology Data Exchange (ETDEWEB)

Araujo, E.M. de; Medeiros, M.R.A.; Paiva, A.K.O.; Borges, F.M.M., E-mail: eduardamedeirosdearaujo@gmail.com [Universidade Federal do Rio Grande do Norte (UFRN), RN (Brazil); Ruiz, J.A.C. [Centro de Tecnologia do Gas e Energias Renovaveis (CTGAS-ER), RN (Brazil)

2016-07-01

Increased air pollution intensified the search for materials that could convert pollutant gases into less harmful substances. Thus, mixed oxides with perovskite structure began to be developed for presenting important features for the automotive catalysis. In this study has been compared the chemical composition of the materials with Pr{sub (1-x)}Ca{sub x}CoO{sub 3} and Gd{sub (1-x)}Ca{sub x}CoO{sub 3} (x = 0.2) synthesized by the method gelatine. The samples were characterized by techniques: Thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), X-Ray Diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray fluorescence (XRF) and subjected to the catalytic test in methane combustion reaction. The evaluation of the catalytic activity showed that gadolinium catalyst is more efficient compared with the praseodymium catalyst, although they have similar maximum conversion of methane at high temperature, during the catalytic test the material with gadolinium showed higher catalytic activity and stability. (author)

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

Energy Technology Data Exchange (ETDEWEB)

1992-02-01

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

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

International Nuclear Information System (INIS)

1992-02-01

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

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

Energy Technology Data Exchange (ETDEWEB)

Yanagisawa, Yasuhide [Faculty of Pharmaceutical Sciences, Chiba Institute of Science, 15-8 Shiomi-cho, Choshi, Chiba 288-0025 (Japan); Chatake, Toshiyuki [Research Reactor Institute, Kyoto University, Asashironishi 2, Kumatori, Sennan, Osaka 590-0494 (Japan); Chiba-Kamoshida, Kaori [National Institute of Advanced Industrial Science and Technology (AIST), Umezono 1-1-1, Tsukuba, Ibaraki 305-8568 (Japan); Naito, Sawa; Ohsugi, Tadanori; Sumi, Hiroyuki [Kurashiki University of Science and Arts, Nishinoura 2640, Tsurajima-cho, Kurashiki, Okayama 712-8505 (Japan); Yasuda, Ichiro [Faculty of Pharmaceutical Sciences, Chiba Institute of Science, 15-8 Shiomi-cho, Choshi, Chiba 288-0025 (Japan); Morimoto, Yukio [Research Reactor Institute, Kyoto University, Asashironishi 2, Kumatori, Sennan, Osaka 590-0494 (Japan); Faculty of Pharmaceutical Sciences, Chiba Institute of Science, 15-8 Shiomi-cho, Choshi, Chiba 288-0025 (Japan)

2010-12-01

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

Sub-atomic resolution X-ray crystallography and neutron crystallography: promise, challenges and potential.

Science.gov (United States)

Blakeley, Matthew P; Hasnain, Samar S; Antonyuk, Svetlana V

2015-07-01

The International Year of Crystallography saw the number of macromolecular structures deposited in the Protein Data Bank cross the 100000 mark, with more than 90000 of these provided by X-ray crystallography. The number of X-ray structures determined to sub-atomic resolution (i.e. ≤1 Å) has passed 600 and this is likely to continue to grow rapidly with diffraction-limited synchrotron radiation sources such as MAX-IV (Sweden) and Sirius (Brazil) under construction. A dozen X-ray structures have been deposited to ultra-high resolution (i.e. ≤0.7 Å), for which precise electron density can be exploited to obtain charge density and provide information on the bonding character of catalytic or electron transfer sites. Although the development of neutron macromolecular crystallography over the years has been far less pronounced, and its application much less widespread, the availability of new and improved instrumentation, combined with dedicated deuteration facilities, are beginning to transform the field. Of the 83 macromolecular structures deposited with neutron diffraction data, more than half (49/83, 59%) were released since 2010. Sub-mm(3) crystals are now regularly being used for data collection, structures have been determined to atomic resolution for a few small proteins, and much larger unit-cell systems (cell edges >100 Å) are being successfully studied. While some details relating to H-atom positions are tractable with X-ray crystallography at sub-atomic resolution, the mobility of certain H atoms precludes them from being located. In addition, highly polarized H atoms and protons (H(+)) remain invisible with X-rays. Moreover, the majority of X-ray structures are determined from cryo-cooled crystals at 100 K, and, although radiation damage can be strongly controlled, especially since the advent of shutterless fast detectors, and by using limited doses and crystal translation at micro-focus beams, radiation damage can still take place. Neutron

Sub-atomic resolution X-ray crystallography and neutron crystallography: promise, challenges and potential

Directory of Open Access Journals (Sweden)

Matthew P. Blakeley

2015-07-01

Full Text Available The International Year of Crystallography saw the number of macromolecular structures deposited in the Protein Data Bank cross the 100000 mark, with more than 90000 of these provided by X-ray crystallography. The number of X-ray structures determined to sub-atomic resolution (i.e. ≤1 Å has passed 600 and this is likely to continue to grow rapidly with diffraction-limited synchrotron radiation sources such as MAX-IV (Sweden and Sirius (Brazil under construction. A dozen X-ray structures have been deposited to ultra-high resolution (i.e. ≤0.7 Å, for which precise electron density can be exploited to obtain charge density and provide information on the bonding character of catalytic or electron transfer sites. Although the development of neutron macromolecular crystallography over the years has been far less pronounced, and its application much less widespread, the availability of new and improved instrumentation, combined with dedicated deuteration facilities, are beginning to transform the field. Of the 83 macromolecular structures deposited with neutron diffraction data, more than half (49/83, 59% were released since 2010. Sub-mm3 crystals are now regularly being used for data collection, structures have been determined to atomic resolution for a few small proteins, and much larger unit-cell systems (cell edges >100 Å are being successfully studied. While some details relating to H-atom positions are tractable with X-ray crystallography at sub-atomic resolution, the mobility of certain H atoms precludes them from being located. In addition, highly polarized H atoms and protons (H+ remain invisible with X-rays. Moreover, the majority of X-ray structures are determined from cryo-cooled crystals at 100 K, and, although radiation damage can be strongly controlled, especially since the advent of shutterless fast detectors, and by using limited doses and crystal translation at micro-focus beams, radiation damage can still take place

X-ray diffraction study of surface-layer structure in parallel grazing rays

International Nuclear Information System (INIS)

Shtypulyak, N.I.; Yakimov, I.I.; Litvintsev, V.V.

1989-01-01

An x-ray diffraction method is described for study of thin polycrystalline and amorphous films and surface layers in an extremely asymmetrical diffraction system in parallel grazing rays using a DRON-3.0 diffractometer. The minimum grazing angles correspond to diffraction under conditions of total external reflection and a layer depth of ∼ 2.5-8 nm

High-resolution X-ray diffraction studies of multilayers

DEFF Research Database (Denmark)

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

1988-01-01

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

Electronic structure of nanoscale Cu/Pt alloys: A combined X-ray diffraction and X-ray absorption investigations

Energy Technology Data Exchange (ETDEWEB)

Chen Xing [Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, CAS, Beijing (China); Graduate School of the Chinese Academy of Sciences, 100864 Beijing (China); Chu Wangsheng [Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, CAS, Beijing (China); University of Science and Technology of China, Hefei, 230036 (China); Cai Quan [Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, CAS, Beijing (China); Graduate School of the Chinese Academy of Sciences, 100864 Beijing (China); Xia Dingguo [College of Environmental and Energy Engineering, Beijing University of Technology, 100022 Beijing (China); Wu Zhonghua [Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, CAS, Beijing (China); Wu Ziyu [Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, CAS, Beijing (China) and National Center for Nanoscience and Technology (China)]. E-mail: wuzy@ihep.ac.cn

2006-11-15

PVP-protected Cu/Pt clusters were prepared by glycol/water reduction method and characterized with transmission electron microscopy (TEM), X-ray diffraction (XRD) and absorption spectra. TEM and XRD analysis show that the Cu/Pt clusters with different molar ratio have fcc structure with particle size of about 4 nm, while the lattice parameters in these clusters reduce with increasing Cu concentration. From the X-ray absorption near edge structure (XANES) at Cu-K edge and Pt-L{sub 2,3} edge, we demonstrate that the d-electronic states of Cu and Pt are affected by the local environment as a function of Cu/Pt molar ratio. With increasing Cu concentration, Pt loses a fraction of 5d electrons and the hybridization between p- and d-states at Cu sites is enhanced.

Strain/size analysis in ternary compounds AgIn{sub 5} VI{sub 8} (Vi = S, Se, Te) by X-ray diffraction; Analisis de tension/tamano en compuestos ternarios AgIn{sub 5} VI{sub 8} (VI = S, Se, Te) mediante difraccion de rayos X

Energy Technology Data Exchange (ETDEWEB)

Fermin, J. R.; Salcedo, D. Y.; Durante R, C.; Castro, J. A. [Universidad del Zulia, Facultad Experimental de Ciencias, Departamento de Fisica, Maracaibo, Zulia (Venezuela, Bolivarian Republic of)

2017-11-01

In this work, we have study the microstructural properties of the ternary compounds AgIn{sub 5} VI{sub 8} (Vi = S, Se, Te) by X-ray diffraction technique (XRD). The linewidth of the XRD profile is measured as function of the diffraction angle. Structural parameters such as, average grain size, micro strains, and crystalline dislocation density, are obtained on the framework of a strain/size analysis based on the modified Scherrer equation for Gaussian profiles. The crystalline dislocation arrange according to a Gaussian distribution function, indicating that these dislocations are randomly distributed within the grains. (Author)

Supershort avalanche electron beams and x-ray in high-pressure nanosecond discharges

International Nuclear Information System (INIS)

Tarasenko, V F; Baksht, E H; Kostyrya, I D; Lomaev, M I; Rybka, D V

2008-01-01

The properties of a supershort avalanche electron beam (S AEB) and X-ray radiation produced using a nanosecond volume discharge are examined. An electron beam of the runaway electrons with amplitude of ∼ 50 A has been obtained in air atmospheric pressure. It is reported that S AEB is formed in the angle above 2π sr. Three groups of the runaway electrons are formed in a gas diode under atmospheric air pressure, when nanosecond voltage pulses with amplitude of hundreds of kilovolts are applied. The electron beam has been generated behind a 45 μm thick AlBe foil in SF 6 and Xe under the pressure of 2 arm, and in He under the pressure of about 12 atm. The paper gives the analysis of a generation mechanism of SAEB.

Measurements of transient electron density distributions by femtosecond X-ray diffraction

International Nuclear Information System (INIS)

Freyer, Benjamin

2013-01-01

This thesis concerns measurements of transient charge density maps by femtosecond X-ray diffraction. Different X-ray diffraction methods will be considered, particularly with regard to their application in femtosecond X-ray diffraction. The rotation method is commonly used in stationary X-ray diffraction. In the work in hand an X-ray diffraction experiment is demonstrated, which combines the method with ultrafast X-ray pulses. This experiment is the first implementation which makes use of the rotation method to map transient intensities of a multitude of Bragg reflections. As a prototype material Bismuth is used, which previously was studied frequently by femtosecond X-ray diffraction by measuring Bragg reflections successively. The experimental results of the present work are compared with the literature data. In the second part a powder-diffraction experiment will be presented, which is used to study the dynamics of the electron-density distribution on ultrafast time scales. The experiment investigates a transition metal complex after photoexcitation of the metal to ligand charge transfer state. Besides expected results, i. e. the change of the bond length between the metal and the ligand and the transfer of electronic charge from the metal to the ligand, a strong contribution of the anion to the charge transfer was found. Furthermore, the charge transfer has predominantly a cooperative character. That is, the excitation of a single complex causes an alteration of the charge density of several neighboring units. The results show that more than 30 transition-metal complexes and 60 anions contribute to the charge transfer. This collective response is a consequence of the strong coulomb interactions of the densely packed ions.

Historical development of synchrotron x-ray diffraction topography

International Nuclear Information System (INIS)

Kawado, Seiji

2011-01-01

After a short history of X-ray diffraction topography, from the early stage of laboratory X-ray topography to recent synchrotron-radiation applications, is described, the development of science and technology for the synchrotron X-ray topography and its industrial applications are reviewed in more detail. In addition, the recent trend to synchrotron topography research is clarified on the basis of several data obtained from 256 papers which have been published since 2000. (author)

X-ray diffraction study of thermal stress relaxation in ZnO films deposited by magnetron sputtering

Energy Technology Data Exchange (ETDEWEB)

Conchon, F. [Institut P' , Universite de Poitiers-Ensma-UPR CNRS 3346, 86962 Futuroscope (France); Renault, P.O., E-mail: pierre.olivier.renault@univ-poitiers.f [Institut P' , Universite de Poitiers-Ensma-UPR CNRS 3346, 86962 Futuroscope (France); Le Bourhis, E.; Krauss, C.; Goudeau, P. [Institut P' , Universite de Poitiers-Ensma-UPR CNRS 3346, 86962 Futuroscope (France); Barthel, E.; Grachev, S. Yu.; Sondergard, E. [Lab. Surface du Verre et Interfaces (SVI), UMR 125, 93303 Aubervilliers (France); Rondeau, V.; Gy, R. [Lab. Recherche de Saint-Gobain (SGR), 93303 Aubervilliers (France); Lazzari, R.; Jupille, J. [Institut des Nanosciences de Paris (INSP), UMR 7588, 75015 Paris (France); Brun, N. [Lab. Physique des Solides (LPS), UMR 8502, 91405 Orsay (France)

2010-12-30

X-ray diffraction stress analyses have been performed on two different thin films deposited onto silicon substrate: ZnO and ZnO encapsulated into Si{sub 3}N{sub 4} layers. We showed that both as-deposited ZnO films are in a high compressive stress state. In situ X-ray diffraction measurements inside a furnace revealed a relaxation of the as-grown stresses at temperatures which vary with the atmosphere in the furnace and change with Si{sub 3}N{sub 4} encapsulation. The observations show that Si{sub 3}N{sub 4} films lying on both sides of the ZnO film play an important role in the mechanisms responsible for the stress relaxation during heat treatment. The different temperatures observed for relaxation in ambient and argon atmospheres suggest that the thermally activated stress relaxation may be attributed to a variation of the stoichiometry of the ZnO films. The present observations pave the way to fine tuning of the residual stresses through thermal treatment parameters.

X-ray Microprobe for Fluorescence and Diffraction Analysis

International Nuclear Information System (INIS)

Ice, G.E.

2005-01-01

X-ray diffraction (see unit 1.1) and x-ray excited fluorescence analysis are powerful techniques for the nondestructive measurement of crystal structure and chemical composition. X-ray fluorescence analysis is inherently nondestructive with orders of magnitude lower power deposited for the same detectable limit as with fluorescence excited by charged particle probes (Sparks, 1980). X-ray diffraction analysis is sensitive to crystal structure with orders-of-magnitude greater sensitivity to crystallographic strain than electron probes (Rebonato, et al. 1989). When a small-area x-ray microbeam is used as the probe, chemical composition (Z>14), crystal structure, crystalline texture, and crystalline strain distributions can be determined. These distributions can be studied both at the surface of the sample and deep within the sample (Fig. 1). Current state-of-the-art can achieve an ∼1 mm-D x-ray microprobe and an ∼0.1 mm-D x-ray microprobe has been demonstrated (Bilderback, et al., 1994). Despite their great chemical and crystallographic sensitivities, x-ray microprobe techniques have until recently been restricted by inefficient x-ray focusing optics and weak x-ray sources; x-ray microbeam analysis was largely superseded by electron techniques in the 50's. However, interest in x-ray microprobe techniques has now been revived (Howells, et al., 1983; Ice and Sparks, 1984; Chevallier, et al., 1997; Riekel 1992; Thompson, el al., 1992; and Making and Using... 1997) by the development of efficient x-ray focusing optics and ultra-high intensity synchrotron x-ray sources (Buras and Tazzari, 1984; Shenoy, et al., 1988). These advances have increased the achievable microbeam flux by more than 11 orders of magnitude (Fig. 2) (Ice, 1997); the flux in a tunable 1 mm-D beam on a 'so called' 3rd-generation synchrotron source such as the APS can exceed the flux in a fixed-energy mm2 beam on a conventional source. These advances make x-ray microfluorescence and x-ray

Determination of crystal structures by x-ray diffraction: applications to a lanthanide complex and a natural organic compound

International Nuclear Information System (INIS)

Miranda, J.M. de.

1986-01-01

The study fir determining crystal structures of the Ho (ReO sub(4)) sub(3) 4 TDTD 3 H sub(2) O complex and the natural organic compound C sub(14) H sub(16) O sub(6) by X-ray diffraction are presented. The experimental equipments are described in details. (M.C.K.)

X-ray diffraction using the time structure of the SRS

International Nuclear Information System (INIS)

Tanner, B.K.

1983-01-01

The subject is discussed under the headings: introduction (advances in the techniques of X-ray topography; comparison with transmission electron microscopy); stroboscopic X-ray topography; stroboscopic X-ray topography of travelling surface acoustic waves; possible general diffraction experiments. (U.K.)

Purification, crystallization and preliminary X-ray diffraction studies of UDP-N-acetylglucosamine pyrophosphorylase from Candida albicans

Energy Technology Data Exchange (ETDEWEB)

Maruyama, Daisuke; Nishitani, Yuichi; Nonaka, Tsuyoshi; Kita, Akiko [Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502 (Japan); Fukami, Takaaki A.; Mio, Toshiyuki; Yamada-Okabe, Hisafumi [Kamakura Research Laboratory, Chugai Pharmaceutical Co. Ltd, 200 Kajiwara, Kamakura, Kanagawa 247-8530 (Japan); Yamada-Okabe, Toshiko [Department of Hygiene, School of Medicine, Yokohama City University, 3-9 Fukuura, Kanazawa, Yokohama 236-0004 (Japan); Miki, Kunio, E-mail: miki@kuchem.kyoto-u.ac.jp [Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502 (Japan); RIKEN SPring-8 Center at Harima Institute, Koto 1-1-1, Sayocho, Sayo-gun, Hyogo 679-5148 (Japan)

2006-12-01

UDP-N-acetylglucosamine pyrophosphorylase was purified and crystallized and X-ray diffraction data were collected to 2.3 Å resolution. UDP-N-acetylglucosamine pyrophosphorylase (UAP) is an essential enzyme in the synthesis of UDP-N-acetylglucosamine. UAP from Candida albicans was purified and crystallized by the sitting-drop vapour-diffusion method. The crystals of the substrate and product complexes both diffract X-rays to beyond 2.3 Å resolution using synchrotron radiation. The crystals of the substrate complex belong to the triclinic space group P1, with unit-cell parameters a = 47.77, b = 62.89, c = 90.60 Å, α = 90.01, β = 97.72, γ = 92.88°, whereas those of the product complex belong to the orthorhombic space group P2{sub 1}2{sub 1}2{sub 1}, with unit-cell parameters a = 61.95, b = 90.87, c = 94.88 Å.

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

DEFF Research Database (Denmark)

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

2010-01-01

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

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

International Nuclear Information System (INIS)

Srinivasan, C.; Balasingh, C.; Singh, A.K.

1979-07-01

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

Synthesis of diluted magnetic semiconductor Bi{sub 2−x}Mn{sub x}Te{sub 3} nanocrystals in a host glass matrix

Energy Technology Data Exchange (ETDEWEB)

Silva, R.S. [Instituto de Ciências Exatas, Naturais e Educação (ICENE), Departamento de Física, Universidade Federal do Triângulo Mineiro, 38025-180 Uberaba, Minas Gerais (Brazil); Mikhail, H.D., E-mail: ricardosilva@fisica.uftm.edu.br [Instituto de Ciências Tecnológicas e Exatas (ICTE), Departamento de Engenharia Mecânica, Universidade Federal do Triângulo Mineiro, 38064-200 Uberaba, Minas Gerais (Brazil); Pavani, R. [Instituto de Ciências Exatas, Naturais e Educação (ICENE), Departamento de Física, Universidade Federal do Triângulo Mineiro, 38025-180 Uberaba, Minas Gerais (Brazil); Cano, N.F. [Departamento de Ciências do Mar, Universidade Federal de São Paulo, 11030-400 Santos, São Paulo (Brazil); Silva, A.C.A.; Dantas, N.O. [Instituto de Física, Laboratório de Novos Materiais Isolantes e Semicondutores (LNMIS), Universidade Federal de Uberlândia, 38400-902 Uberlândia, Minas Gerais (Brazil)

2015-11-05

Diluted magnetic semiconductors of manganese doped in bismuth-telluride nanocrystals (Bi{sub 2−x}Mn{sub x}Te{sub 3} NCs) were grown in a glass matrix and investigated by Transmission Electron Microscopy, X-Ray Diffraction, Atomic Force Microscopy/Magnetic Force Microscopy, and Electron Paramagnetic Resonance. TEM images showed that the nanocrystals formed within the glass matrix were nearly spherical, with average sizes between 4 and 5 nm, and d{sub 015}-spacing of approximately 0.322 nm, which corresponds to the (015) interplanar distance in Bi{sub 2}Te{sub 3} bulk. The diffraction patterns showed that the diffraction peak associated with the (015) plane of the Bi{sub 2−x}Mn{sub x}Te{sub 3} nanocrystals shifts to larger diffraction angles as manganese (Mn) concentration increases, suggesting that the Mn{sup 2+} ions are substitutional defects occupying Bi sites (Mn{sub Bi}). AFM and MFM measurements showed magnetic phase contrast patterns, providing further evidence of Mn{sup 2+} ion incorporation in the nanocrystal structure. EPR signal of manganese ion incorporation and valence states in the crystalline structure of the Bi{sub 2}Te{sub 3} nanocrystals confirmed the presence of the Mn{sup 2+} state. - Highlights: • Bi{sub 2−x}Mn{sub x}Te{sub 3} NCs were synthesized in a glass matrix by fusion method. • Transmission Electronic Microscopy shows the formation of Bi{sub 2−x}Mn{sub x}Te{sub 3} NCs. • The sp-d exchange interaction in DMS NCs can be evidenced by X Ray-Diffraction and Magnetic Force Microscopy. • Electron Paramagnetic Resonance spectra confirmed that Mn{sup 2+} ions are located in two distinct Bi{sub 2}Te{sub 3} NCs sites.

Synthesis and crystal structure of K{sub 2}NiF{sub 4}-type novel Gd{sub 1+x}Ca{sub 1−x}AlO{sub 4−x}N{sub x} oxynitrides

Energy Technology Data Exchange (ETDEWEB)

Masubuchi, Yuji, E-mail: yuji-mas@eng.hokudai.ac.jp; Hata, Tomoyuki; Motohashi, Teruki; Kikkawa, Shinichi

2014-01-05

Highlights: • Novel gadolinium calcium aluminum oxynitride was prepared by solid state reaction. • Crystal structure of the oxynitride was refined by using synchrotron X-ray diffraction. • Gd{sub 1.2}Ca{sub 0.8}AlO{sub 3.8}N{sub 0.2} has a layered K{sub 2}NiF{sub 4}-type structure with the I4mm space group. • Nitride ions preferentially occupy the apical site of aluminum octahedron. -- Abstract: Novel gadolinium calcium aluminum oxynitrides, Gd{sub 1+x}Ca{sub 1−x}AlO{sub 4−x}N{sub x}, were prepared in x = 0.15–0.25 by the solid state reaction of a nitrogen–rich mixture with AlN as an aluminum source; the mixture was sintered twice at 1500 °C for 5 h under 0.5 MPa of nitrogen gas. Shift in the optical absorption edge was observed in their diffuse reflectance spectra from 4.46 eV for the oxide (x = 0) to 2.94 eV for the oxynitride at x = 0.2. The crystal structure of Gd{sub 1.2}Ca{sub 0.8}AlO{sub 3.8}N{sub 0.2} at x = 0.2 was refined using a synchrotron X-ray diffraction data as a layered K{sub 2}NiF{sub 4}-type structure with the I4mm space group. Longer Al–O/N bond lengths in the oxynitride than those in GdCaAlO{sub 4} suggest that the nitride ions are in the apical site of aluminum polyhedron, similar to those in Nd{sub 2}AlO{sub 3}N.

Three-Dimensional X-Ray Diffraction Technique for Metals Science

DEFF Research Database (Denmark)

Zhang, Yubin; Fan, Guohua

2017-01-01

The three-dimensional X-ray diffraction (3DXRD) is a new, advanced technique for materials characterization. This technique utilizes high-energy synchrotron X-rays to characterize the 3D crystallographic structure and strain/stress state of bulk materials. As the measurement is non......-destructive, the microstructural evolution as a function of time can be followed, i.e. it allows 4D (x, y, z characterizations, t). The high brilliance of synchrotron X-rays ensures that diffraction signals from volumes of micrometer scale can be quickly detected and distinguished from the background noise, i.e. its spatial...... implemented in several large synchrotron facilities, e.g. the Advanced Photon Source (APS) in USA and the Spring-8 in Japan. Another family of 3DXRD technique that utilizes white beam synchrotron X-rays has also been developed in parallel in cooperation between Oak Ridge National Laboratory and APS...

Takagi-Taupin description of x-ray dynamical diffraction from diffractive optics with large numerical aperture

International Nuclear Information System (INIS)

Yan Hanfei; Maser, Joerg; Macrander, Albert; Shen Qun; Vogt, Stefan; Stephenson, G. Brian; Kang, Hyon Chol

2007-01-01

We present a formalism of x-ray dynamical diffraction from volume diffractive optics with large numerical aperture and high aspect ratio, in an analogy to the Takagi-Taupin equations [Acta Crystallogr. 15, 1311 (1962); Bull. Soc. Fr. Mineral. Crystallogr. 87, 469 (1964)] for strained single crystals. We derive a set of basic equations for dynamical diffraction from volume diffractive optics, which enable us to study the focusing property of these optics with various grating profiles. We study volume diffractive optics that satisfy the Bragg condition to various degrees, namely, flat, tilted, and wedged geometries, and derive the curved geometries required for ultimate focusing. We show that the curved geometries satisfy both the Bragg condition everywhere and phase requirement for point focusing and effectively focus hard x rays to a scale close to the wavelength. Our calculations were made for an x-ray wavelength of 0.064 nm (19.5 keV)

Study of Inverse Ni-based Photonic Crystal using the Microradian X-ray Diffraction

Energy Technology Data Exchange (ETDEWEB)

Vasilieva, A V; Okorokov, A I; Grigoriev, S V [Petersburg Nuclear Physics Institute, Gatchina, 188350, St. Petersburg (Russian Federation); Grigoryeva, N A; Mistonov, A A [Department of Physics, St. Petersburg State University, 198504, St. Petersburg (Russian Federation); Sapoletova, N A; Napolskii, K S; Eliseev, A A; Lukashin, A V; Tretyakov, Yu D [Department of Materials Science, Moscow State University, 119899, Moscow (Russian Federation); Petukhov, A V; Byelov, D [Debye Institute, Utrecht University, 3584 CH Utrecht (Netherlands); Chernyshov, D [SNBL European Synchrotron Radiation Facility (ESRF), 38043 Grenoble (France); Bouwman, W G, E-mail: vasilieva@lns.pnpi.spb.r [Delft Technical University, 2629 JB Delft (Netherlands)

2010-10-01

Inverse photonic nickel-based crystal films formed by electrocrystallization of metal inside the voids of polymer artificial opal have been studied using the microradian X-ray diffraction. Analysis of the diffraction images agrees with an face-centred cubic (FCC) structure with the lattice constant a{sub 0} = 650 {+-} 10 nm and indicates two types of stacking sequences coexisting in the crystal (twins of ABCABC... and ACBACB... ordering motifs), the ratio between them being 4:5 The transverse structural correlation length L{sub tran} is 2.4 {+-} 0.1 {mu}m, which corresponds to a sample thickness of 6 layers. The in-plane structural correlation length L{sub long} is 3.4 {+-} 0.2 {mu}m, and the structure mosaic is of order of 10{sup 0}.

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

Energy Technology Data Exchange (ETDEWEB)

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)

2014-04-14

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.

Illicit drug detection using energy dispersive x-ray diffraction

Science.gov (United States)

Cook, E. J.; Griffiths, J. A.; Koutalonis, M.; Gent, C.; Pani, S.; Horrocks, J. A.; George, L.; Hardwick, S.; Speller, R.

2009-05-01

Illicit drugs are imported into countries in myriad ways, including via the postal system and courier services. An automated system is required to detect drugs in parcels for which X-ray diffraction is a suitable technique as it is non-destructive, material specific and uses X-rays of sufficiently high energy to penetrate parcels containing a range of attenuating materials. A database has been constructed containing the measured powder diffraction profiles of several thousand materials likely to be found in parcels. These include drugs, cutting agents, packaging and other innocuous materials. A software model has been developed using these data to predict the diffraction profiles which would be obtained by X-ray diffraction systems with a range of suggested detector (high purity germanium, CZT and scintillation), source and collimation options. The aim of the model was to identify the most promising system geometries, which was done with the aid of multivariate analysis (MVA). The most promising systems were constructed and tested. The diffraction profiles of a range of materials have been measured and used to both validate the model and to identify the presence of drugs in sample packages.

X-ray powder diffraction analysis of liquid-phase-sintered silicon carbide ceramics

Energy Technology Data Exchange (ETDEWEB)

Ortiz, A.L.; Sanchez-Bajo, F. [Universidad de Extremadura, Badajoz (Spain). Dept. de Electronica e Ingenieria Electromecanica; Cumbrera, F.L. [Universidad de Extremadura, Badajoz (Spain). Dept. de Fisica

2002-07-01

In an attempt to gain a comprehensive understanding of the microstructural evolution in liquid-phase-sintered silicon carbide ceramics, the effect of the starting {beta}-SiC powder has been studied. Pellets of two different {beta}-SiC starting powders were sintered with simultaneous additions of Al{sub 2}O{sub 3} and Y{sub 2}O{sub 3} at 1950 C for 1 hour in flowing argon atmosphere. Here we have used X-ray diffraction to obtain the relative abundance of the resulting SiC polytypes after sintering. The significant influence of the defects concentration on the {beta} to {alpha} transformation rate has been determined using the Rietveld method. (orig.)

Hydrogen atoms in protein structures: high-resolution X-ray diffraction structure of the DFPase

Science.gov (United States)

2013-01-01

Background Hydrogen atoms represent about half of the total number of atoms in proteins and are often involved in substrate recognition and catalysis. Unfortunately, X-ray protein crystallography at usual resolution fails to access directly their positioning, mainly because light atoms display weak contributions to diffraction. However, sub-Ångstrom diffraction data, careful modeling and a proper refinement strategy can allow the positioning of a significant part of hydrogen atoms. Results A comprehensive study on the X-ray structure of the diisopropyl-fluorophosphatase (DFPase) was performed, and the hydrogen atoms were modeled, including those of solvent molecules. This model was compared to the available neutron structure of DFPase, and differences in the protein and the active site solvation were noticed. Conclusions A further examination of the DFPase X-ray structure provides substantial evidence about the presence of an activated water molecule that may constitute an interesting piece of information as regard to the enzymatic hydrolysis mechanism. PMID:23915572

X-ray diffraction identification of clay minerals by microcomputer

International Nuclear Information System (INIS)

Rodrigues, S.; Imasava, F.J.

1988-01-01

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

Modern trends in x-ray powder diffraction

International Nuclear Information System (INIS)

Goebel, H.E.; Snyder, R.L.

1985-01-01

The revival of interest in X-ray powder diffraction, being quoted as a metamorphosis from the 'ugly duckling' to a 'beautiful swan', can be attributed to a number of modern developments in instrumentation and evaluation software. They result in faster data collection, improved accuracy and resolution, and better detectability of minor phases. The ease of data evaluation on small computers coupled direct to the instrument allows convenient execution of previously tedious and time-consuming off-line tasks like qualitative and quantitative analysis, characterization of microcrystalline properties, indexing, and lattice-constant refinements, as well as structure refinements or even exploration of new crystal structures. Powder diffraction has also progressed from an isolated analytical laboratory method to an in situ technique for analysing solid-state reactions or for the on-stream control of industrial processes. The paper surveys these developments and their real and potential applications, and tries to emphasize new trends that are regarded as important steps for the further progress of X-ray powder diffraction

Magnetic interactions in HoCr{sub 1-x}Fe{sub x}O{sub 3} (x = 0, 0.2) investigated by neutron powder diffraction

Energy Technology Data Exchange (ETDEWEB)

Liu, Xinzhi, E-mail: liuxinzhi1984.cn@163.com [Department of Nuclear Physics, China Institute of Atomic Energy, Beijing 102413 (China); Hao, Lijie; Ma, Xiaobai [Department of Nuclear Physics, China Institute of Atomic Energy, Beijing 102413 (China); Wang, Chin-Wei [Neutron Group, National Synchrotron Radiation Research Center, Hsinchu 30077, Taiwan (China); Klose, Frank [Australian Nuclear Science and Technology Organization, Lucas Heights, New South Wales 2234 (Australia); Department of Physics and Materials Science, The City University of Hong Kong, Hong Kong Special Administrative Region (Hong Kong); Liu, Yuntao, E-mail: ytliu@ciae.ac.cn [Department of Nuclear Physics, China Institute of Atomic Energy, Beijing 102413 (China); Sun, Kai; Li, Yuqing [Department of Nuclear Physics, China Institute of Atomic Energy, Beijing 102413 (China); Chen, Dongfeng, E-mail: dongfeng@ciae.ac.cn [Department of Nuclear Physics, China Institute of Atomic Energy, Beijing 102413 (China)

2017-07-01

Highlights: • The temperature dependent magnetism of HoCr{sub 1-x}Fe{sub x}O{sub 3} (x = 0, 0.2) were investigated by neutron diffraction. • Cr{sup 3+} moment follows a mean field theory while Ho{sup 3+} follows a spin 1/2 model. • An magneto-elastic strain was observed accompanying with the ordering of Cr{sup 3+}. - Abstract: The temperature dependent magnetism of Fe-doped rare earth orthochromite HoCr{sub 1-x}Fe{sub x}O{sub 3}(x = 0, 0.2) was investigated by neutron powder diffraction. It is found that the magnetism of Cr(Fe){sup 3+} can be well understood within mean field theory, while the ordering of Ho{sup 3+} was induced by the Cr(Fe){sup 3+} sublattice and can be satisfyingly described by an effective S = 1/2 model. The absences of both the most common G{sub x}F{sub z} configuration of Cr{sup 3+} and the ordering of Ho{sup 3+} caused by Ho-Ho interaction evidence a strong Ho{sup 3+}-Cr{sup 3+} interaction which dominates this system. On the other hand, a remarkable magnetoelastic strain was observed accompanying the Cr(Fe){sup 3+} ordering. An analysis based on the equation of state with a Grüneisen approximation was performed and revealed magnetic origin of this strain.

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

International Nuclear Information System (INIS)

Stern, Stephan

2013-12-01

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

Modern X-ray diffraction. X-ray diffractometry for materials scientists, physicists, and chemicists. 2. rev. and enl. ed.

International Nuclear Information System (INIS)

Spiess, Lothar; Teichert, Gerd; Schwarzer, Robert; Behnken, Herfried; Genzel, Christoph

2009-01-01

This book offers a comprehensive survey over the applications of X-ray diffractions in fields like materials technique, metallurgy, electrotechniques, mechanical engineering, as well as micro- and nanotechniques. The necessary baic knowledges of X-ray diffraction are mediated foundedly and illustratively. Thereby new techniques and evaluation procedures are presented as well as well known methods

X-ray and neutron diffraction studies of crystallinity in hydroxyapatite coatings.

Science.gov (United States)

Girardin, E; Millet, P; Lodini, A

2000-02-01

To standardize industrial implant production and make comparisons between different experimental results, we have to be able to quantify the crystallinity of hydroxyapatite. Methods of measuring crystallinity ratio were developed for various HA samples before and after plasma spraying. The first series of methods uses X-ray diffraction. The advantage of these methods is that X-ray diffraction equipment is used widely in science and industry. In the second series, a neutron diffraction method is developed and the results recorded are similar to those obtained by the modified X-ray diffraction methods. The advantage of neutron diffraction is the ability to obtain measurements deep inside a component. It is a nondestructive method, owing to the very low absorption of neutrons in most materials. Copyright 2000 John Wiley & Sons, Inc.

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

Energy Technology Data Exchange (ETDEWEB)

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

2016-08-19

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

X-ray diffraction from single GaAs nanowires

Energy Technology Data Exchange (ETDEWEB)

Biermanns, Andreas

2012-11-12

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

Experimental coherent X-ray diffractive imaging: capabilities and limitations of the technique

International Nuclear Information System (INIS)

Schropp, Andreas

2008-08-01

The investigations pursued during this work were focused on the testing of the applicability of the coherent X-ray diffractive imaging(CXDI)-method in the hard X-ray regime and different measurements were carried out at photon energies between 7 keV and 10 keV. The samples investigated were lithographically prepared two-dimensional gold structures with a size ranging from 3 μm to 10 μm as well as a cluster of gold spheres with a lateral extension of about 3.5 μm. Continuous diffraction patterns were recorded in small angle scattering geometry. In some of the measurements a scattering signal up to the edge of the detector could be measured which corresponds to a lateral resolution of about 30 nm. For certain samples it was possible to reconstruct the object from the measured diffraction data. Since the scattered intensity of non-periodic objects is weak at large scattering angles, the available photon flux is finally the main limitation of the method with regard to the achievable resolution. The experimental data were used to get an estimate of photon flux required for sub-nanometer resolution. The ptychographic iterative phase retrieval algorithm proposed by J. M. Rodenburg et al. (2004) was implemented and tested on simulated diffraction data. Additionally, a genetic algorithm has been developed and implemented for phase retrieval. This algorithm is very different from state-of-the-art algorithms and allows to introduce further experimentally important parameters such as a certain illumination function and partial coherence of the X-ray light. (orig.)

Al{sub 0.2}Ga{sub 0.8}As X-ray photodiodes for X-ray spectroscopy

Energy Technology Data Exchange (ETDEWEB)

Whitaker, M.D.C., E-mail: M.Whitaker@sussex.ac.uk; Lioliou, G.; Butera, S.; Barnett, A.M.

2016-12-21

Three custom-made Al{sub 0.2}Ga{sub 0.8}As p-i-n mesa X-ray photodiodes (200 µm diameter, 3 µm i layer) were electrically characterised and investigated for their response to illumination with soft X-rays from an {sup 55}Fe radioisotope X-ray source (Mn Kα = 5.9 keV; Mn Kβ = 6.49 keV). The AlGaAs photodiodes were shown to be suitable for photon counting X-ray spectroscopy at room temperature. When coupled to a custom-made low-noise charge-sensitive preamplifier, a mean energy resolution (as quantified by the full width at half maximum of the 5.9 keV photopeak) of 1.24 keV was measured at room temperature. Parameters such as the depletion width (1.92 µm at 10 V), charge trapping noise (61.7 e{sup −} rms ENC at 5 V, negligible at 10 V) and the electronic noise components (known dielectric noise (63.4 e{sup −} rms), series white noise (27.7 e{sup −} rms), parallel white noise (9.5 e{sup −} rms) and 1/f series noise (2.2 e{sup −} rms) at 10 V reverse bias) affecting the achieved energy resolution were computed. The estimated charge trapping noise and mean energy resolution were compared to similar materials (e.g. Al{sub 0.8}Ga{sub 0.2}As) previously reported, and discussed. These results are the first demonstration of photon counting X-ray spectroscopy with Al{sub 0.2}Ga{sub 0.8}As reported to date.

X-ray diffraction studies of NbTe 2 single crystal

Indian Academy of Sciences (India)

The composition of the grown crystals was confirmed on the basis of energy dispersive analysis by X-ray (EDAX) and remaining structural characterization was also accomplished by X-ray diffraction (XRD) studies. Lattice parameters, volume and X-ray density have been carried out for the grown crystals. The particle size ...

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

International Nuclear Information System (INIS)

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

2016-01-01

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

An introduction to three-dimensional X-ray diffraction microscopy

DEFF Research Database (Denmark)

Poulsen, Henning Friis

2012-01-01

Three-dimensional X-ray diffraction microscopy is a fast and nondestructive structural characterization technique aimed at studies of the individual crystalline elements (grains or subgrains) within millimetre-sized polycrystalline specimens. It is based on two principles: the use of highly...... penetrating hard X-rays from a synchrotron source and the application of tomographic reconstruction algorithms for the analysis of the diffraction data. In favourable cases, the position, morphology, phase and crystallographic orientation can be derived for up to 1000 elements simultaneously. For each grain...

Facile synthesis, structure elucidation, and magnetic properties of perovskite BaTb{sub 1-x}Bi{sub x}O{sub 3}

Energy Technology Data Exchange (ETDEWEB)

Farid, Muhammad Asim; Zhang, Hao; Li, Guobao; Liao, Fuhui; Lin, Jianhua [Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Rare Earth Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peking University, 100871, Beijing (China); Yang, Aimei [College of Materials Science and Engineering, Guilin University of Technology, 541004, Guilin (China); Tian, Gengfang; Wu, Meimei [Neutron Scattering Laboratory, Department of Nuclear Physics, China Institute of Atomic Energy, 102413, Beijing (China)

2017-03-17

A series of perovskite BaTb{sub 1-x}Bi{sub x}O{sub 3} (0.0 ≤ x ≤ 0.25) solid solutions were synthesized by a typical solid-state method. Their structures were analyzed by a combination of X-ray diffraction, neutron diffraction, and selected-area electron diffraction. All of the materials crystalize in the P1 space group [a = 6.0582(1) Aa, b = 6.0473(1) Aa, c = 6.0693(1) Aa, α = 60.00(1) , β = 59.84(1) , γ = 60.06(1) for x = 0.0 at room temperature]. Magnetic measurements revealed that the magnetic-ordering temperature decreases with increasing Bi content in BaTb{sub 1-x}Bi{sub x}O{sub 3}; therefore, the presence of Bi decreases the magnetic interactions of Tb. Furthermore, the magnetic structure for BaTb{sub 1-x}Bi{sub x}O{sub 3} has been fully described in space group P1. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Direct observation of radial distribution change during tensile deformation of metallic glass by high energy X-ray diffraction method

Energy Technology Data Exchange (ETDEWEB)

Nasu, Toshio, E-mail: nasu@kekexafs.kj.yamagata-u.ac.j [Faculty of Education, Arts and Science, Yamagata University, 1-4-12 Kojirakawa, Yamagata, Yamagata, 990-8560 (Japan); Sasaki, Motokatsu [Faculty of Education, Arts and Science, Yamagata University, 1-4-12 Kojirakawa, Yamagata, Yamagata, 990-8560 (Japan); Usuki, Takeshi; Sekine, Mai [Faculty of Science, Yamagata University, Yamagata 990-8560 (Japan); Takigawa, Yorinobu; Higashi, Kenji [Graduate School of Engineering, Osaka Prefecture University, Sakai 599-8531 (Japan); Kohara, Shinji [Japan Synchrotron Radiation Research Institute, Harima Science Garden City, Sayo town, Hyogo 679-5198 (Japan); Sakurai, Masaki; Wei Zhang; Inoue, Akihisa [Institute for Materials Research, Tohoku University, Sendai 980-8577 (Japan)

2009-08-26

The purpose of this research is to investigate the micro-mechanism of deformation behavior of metallic glasses. We report the results of direct observations of short-range and medium-range structural change during tensile deformation of metallic glasses by high energy X-ray diffraction method. Cu{sub 50}Zr{sub 50} and Ni{sub 30}Zr{sub 70} metallic glass samples in the ribbon shape (1.5 mm width and 25 mum) were made by using rapid quenching method. Tensile deformation added to the sample was made by using special equipment adopted for measuring the high energy X-ray diffraction. The peaks in pair distribution function g(r) for Cu{sub 50}Zr{sub 50} and N{sub 30}iZr{sub 70} metallic glasses move zigzag into front and into rear during tensile deformation. These results of direct observation on atomic distribution change for Cu{sub 50}Zr{sub 50} and Ni{sub 30}Zr{sub 70} metallic glass ribbons during tensile deformation suggest that the micro-relaxations occur.

Performances for confocal X-ray diffraction technology based on polycapillary slightly focusing X-ray optics

Energy Technology Data Exchange (ETDEWEB)

Liu, Hehe; Liu, Zhiguo [The Key Laboratory of Beam Technology and Materials Modification of the Ministry of Education, Beijing Normal University, Beijing 100875 (China); College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); Beijing Radiation Center, Beijing 100875 (China); Sun, Tianxi, E-mail: stxbeijing@163.com [The Key Laboratory of Beam Technology and Materials Modification of the Ministry of Education, Beijing Normal University, Beijing 100875 (China); College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); Beijing Radiation Center, Beijing 100875 (China); Peng, Song [The Key Laboratory of Beam Technology and Materials Modification of the Ministry of Education, Beijing Normal University, Beijing 100875 (China); College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); Beijing Radiation Center, Beijing 100875 (China); Ma, Yongzhong [Center for Disease Control and Prevention of Beijing, Beijing 100013 (China); Sun, Weiyuan; Li, Yude; Lin, Xiaoyan; Zhao, Weigang; Zhao, Guangcui; Luo, Ping; Pan, Qiuli; Ding, Xunliang [The Key Laboratory of Beam Technology and Materials Modification of the Ministry of Education, Beijing Normal University, Beijing 100875 (China); College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); Beijing Radiation Center, Beijing 100875 (China)

2013-09-21

The confocal X-ray diffraction (XRD) technology based on a polycapillary slightly focusing X-ray lens (PSFXRL) in excitation channel and a polycapillary parallel X-ray lens (PPXRL) with a long input focal distance in detection channel was developed. The output focal spot of the PSFXRL and the input focal spot of the PPXRL were adjusted in confocal configuration, and only the X-rays from the volume overlapped by these foci could be accordingly detected. This confocal configuration was helpful in decreasing background. The convergence of the beam focused by the PSFXRL and divergence of the beam which could be collected by the PPXRL with a long input focal distance were both about 9 mrad at 8 keV. This was helpful in improving the resolution of lattice spacing of this confocal XRD technology. The gain in power density of such PSFXRL and PPXRL was about 120 and 7 at 11 keV, respectively, which was helpful in using the low power source to perform XRD analysis efficiently. The performances of this confocal XRD technology were provided, and some common plastics were analyzed. The experimental results demonstrated that the confocal diffraction technology base on polycapillary slightly focusing X-ray optics had wide potential applications.

Diffraction anomalous fine structure using X-ray anomalous dispersion

International Nuclear Information System (INIS)

Soejima, Yuji; Kuwajima, Shuichiro

1998-01-01

A use of X-ray anomalous dispersion effects for structure investigation has recently been developed by using synchrotron radiation. One of the interesting method is the observation of anomalous fine structure which arise on diffraction intensity in energy region of incident X-ray at and higher than absorption edge. The phenomenon is so called Diffraction Anomalous Fine Structure (DAFS). DAFS originates in the same physical process an that of EXAFS: namely photoelectric effect at the corresponding atom and the interaction of photoelectron waves between the atom and neighboring atoms. In contrast with EXAFS, the method is available for only the crystalline materials, but shows effective advantages of the structure investigations by a use of diffraction: one is the site selectivity and the other is space selectivity. In the present study, demonstrations of a use of X-ray anomalous dispersion effect for the superstructure determination will be given for the case of PbZrO 3 , then recent trial investigations of DAFS in particular on the superlattice reflections will be introduced. In addition, we discuss about Forbidden Reflection near Edge Diffraction (FRED) which is more recently investigated as a new method of the structure analysis. (author)

Structural analysis of quaternary Se{sub 85−x}Sb{sub 10}In{sub 5}Ag{sub x} bulk glassy alloys

Energy Technology Data Exchange (ETDEWEB)

Sharma, Rita, E-mail: reetasharma2012@gmail.com; Sharma, Shaveta; Kumar, Praveen; Chander, Ravi; Thangaraj, R.; Mian, M. [Semiconductors Laboratory, Department of Physics, GND University, Amritsar (India)

2015-08-28

The physical properties of chalcogenide semiconductor have attracted much attention recently due to their applications in optical recording media and inorganic resist due to photo induced structural transformations observed in these materials. The bulk samples of Se{sub 85-x}Sb{sub 10}In{sub 5}Ag{sub x} system are prepared by melt-quenching technique. X-ray diffraction technique and RAMAN spectroscopy have been used to study the role of Ag additive on the amorphous/crystalline nature and molecular structure of Se{sub 85}Sb{sub 10}In{sub 5} glassy alloys. The phases Sb{sub 2}Se{sub 3}, In-Sb and In{sub 2}Se{sub 3} has been observed by X-ray diffraction. The formation of AgInSe{sub 2} phase along with the enhancement in intensity has been observed with the Ag addition.Three bands observed by raman spectroscopy for Se85Sb10In5 are at 70 cm-1, 212cm-1 and 252cm-1. The formation of small bands up to wavenumber 188cm{sup -1} and shifting in second band along with the increase in intensity up to sample x=5 has been observed with the Ag addition. The enhancement in intensity in third band with Ag content has been observed.

Evaluation of In-Vacuum Imaging Plate Detector for X-Ray Diffraction Microscopy

International Nuclear Information System (INIS)

Nishino, Yoshinori; Takahashi, Yukio; Yamamoto, Masaki; Ishikawa, Tetsuya

2007-01-01

We performed evaluation tests of a newly developed in-vacuum imaging plate (IP) detector for x-ray diffraction microscopy. IP detectors have advantages over direct x-ray detection charge-coupled device (CCD) detectors, which have been commonly used in x-ray diffraction microscopy experiments, in the capabilities for a high photon count and for a wide area. The detector system contains two IPs to make measurement efficient by recording data with the one while reading or erasing the other. We compared speckled diffraction patterns of single particles taken with the IP and a direct x-ray detection CCD. The IP was inferior to the CCD in spatial resolution and in signal-to-noise ratio at a low photon count

Phase composition and superconducting properties of (Pb sub 0 sub . sub 6 Sn sub y Cu sub 0 sub . sub 4 sub - sub y)Sr sub 2 (Y sub 1 sub - sub x Ca sub x)Cu sub 2 O sub z

CERN Document Server

Balchev, N; Kunev, B; Souleva, A; Tsacheva, T

2001-01-01

The effect of Sn-doping in (Pb sub 0 sub . sub 6 Sn sub y Cu sub 0 sub . sub 4 sub - sub y)Sr sub 2 (Y sub 1 sub - sub x Ca sub x)Cu sub 2 O sub z for 0 <= y <= 0.3 and 0 <= x <= 0.7 was investigated. It was established that a nearly pure 1212 phase could be obtained at 0 <= y <= 0.1 and 0 <= x <= 0.3. The obtained X-ray diffraction (XRD) patterns as well as the results of the inductively coupled plasma atomic emission spectrometry (ICP-AES) and energy-dispersive X-ray (EDX) analysis showed that the Sn-substitution was possible in the (Pb,Cu)-1212 phase. Superconductivity was observed at 0.4 <= x <= 0.7. The onset of the diamagnetic transitions varied from 10 to 30 K. The influence of the strong Pb deficiency on the superconducting properties of the samples was discussed. (authors)

X-ray powder diffraction data on miscellaneous lanthanide compounds

International Nuclear Information System (INIS)

Ferguson, I.F.; Hughes, T.E.

1978-08-01

Recent work on neutron absorbing materials has produced various new X-ray diffraction powder patterns of compounds of the lanthanides. Various inconsistencies in previously published data have been noted, and accurate measurements have been made of the lattice parameters of the rare earth oxides Sm 2 0 3 , Eu 2 0 3 , Gd 2 0 3 which have the monoclinic rare earth type B- structure, as well as Eu0. These data are recorded for reference. The optimum conditions for obtaining X-ray powder diffraction data from europium compounds are also noted. (author)

Uranium oxidation kinetics monitored by in-situ X-ray diffraction

Energy Technology Data Exchange (ETDEWEB)

Zalkind, S., E-mail: shimonzl@nrcn.org.il; Rafailov, G.; Halevy, I.; Livneh, T.; Rubin, A.; Maimon, H.; Schweke, D.

2017-03-15

The oxidation kinetics of U-0.1 wt%Cr at oxygen pressures of 150 Torr and the temperature range of 90–150 °C was studied by means of in-situ X-ray diffraction (XRD). A “breakaway” in the oxidation kinetics is found at ∼0.25 μm, turning from a parabolic to a linear rate law. At the initial stage of oxidation the growth plane of UO{sub 2}(111) is the prominent one. As the oxide thickens, the growth rate of UO{sub 2}(220) plane increases and both planes grow concurrently. The activation energies obtained for the oxide growth are Q{sub parabolic} = 17.5 kcal/mol and Q{sub linear} = 19 kcal/mol. Enhanced oxidation around uranium carbide (UC) inclusions is clearly observed by scanning electron microscopy (SEM).

X-ray diffraction of multilayers and superlattices

International Nuclear Information System (INIS)

Bartels, W.J.; Hornstra, J.; Lobeek, D.J.W.

1986-01-01

Recursion formulae for calculating the reflected amplitude ratio of multilayers and superlattices have been derived from the Takagi-Taupin differential equations, which describe the dynamical diffraction of X-rays in deformed crystals. Calculated rocking curves of complicated layered structures, such as non-ideal superlattices on perfect crystals, are shown to be in good agreement with observed diffraction profiles. The kinematical theory can save computing time only in the case of an ideal superlattice, for which a geometric series can be used, but the reflections must be below 10% so that multiple reflections can be neglected. For a perfect crystal of arbitrary thickness the absorption at the center of the dynamical reflection is found to be proportional to the square root of the reflectivity. Sputter-deposited periodic multilayers of tungsten and carbon can be considered as an artificial crystal, for which dynamical X-ray diffraction calculations give results very similar to those of a macroscopic optical description in terms of the complex index of refraction and Fresnel reflection coefficients. (orig.)

X-ray and Neutron Diffraction in the Study of Organic Crystalline Hydrates

Directory of Open Access Journals (Sweden)

Katharina Fucke

2010-07-01

Full Text Available A review. Diffraction methods are a powerful tool to investigate the crystal structure of organic compounds in general and their hydrates in particular. The laboratory standard technique of single crystal X-ray diffraction gives information about the molecular conformation, packing and hydrogen bonding in the crystal structure, while powder X-ray diffraction on bulk material can trace hydration/dehydration processes and phase transitions under non-ambient conditions. Neutron diffraction is a valuable complementary technique to X-ray diffraction and gives highly accurate hydrogen atom positions due to the interaction of the radiation with the atomic nuclei. Although not yet often applied to organic hydrates, neutron single crystal and neutron powder diffraction give precise structural data on hydrogen bonding networks which will help explain why hydrates form in the first place.

X-ray diffraction study of a semiconductor/electrolyte interface: n-GaAs(001)/H<sub>2sub>SO>4sub>(:Cu)

DEFF Research Database (Denmark)

Zegenhagen, J.; Kazimirov, A.; Scherb, G.

1996-01-01

We used X-ray diffraction to investigate the n-GaAs(001)/0.5M H2SO4 interface in-situ under potential control in a three-electrode, thin-layer electrochemical cell. The intensity of crystal truncation rods as a function of the electrode potential was recorded. A pronounced increase in surface rou...

X-ray diffraction and chemical bonding

International Nuclear Information System (INIS)

Bats, J.W.

1976-01-01

Chemical bonds are investigated in sulfamic acid (H 3 N-SO 3 ), sodium sulfonlate dihydrate (H 2 NC 6 H 4 SO 3 Na.2H 2 O), 2,5-dimercaptothiadiazole (HS-C 2 N 2 S-SH), sodium cyanide dihydrate (NaCN.2H 2 O), sodium thiocyanate (NaSCN) and ammonium thiocyanate (NH 4 SCN) by X-ray diffraction, and if necessary completed with neutron diffraction. Crystal structures and electron densities are determined together with bond length and angles. Also the effects of thermal motion are discussed

High-speed classification of coherent X-ray diffraction patterns on the K computer for high-resolution single biomolecule imaging

Energy Technology Data Exchange (ETDEWEB)

Tokuhisa, Atsushi [RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5148 (Japan); Arai, Junya [The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan); Joti, Yasumasa [JASRI, 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5198 (Japan); Ohno, Yoshiyuki; Kameyama, Toyohisa; Yamamoto, Keiji; Hatanaka, Masayuki; Gerofi, Balazs; Shimada, Akio; Kurokawa, Motoyoshi; Shoji, Fumiyoshi [RIKEN Advanced Institute for Computational Science, 7-1-26 Minatojima-minami-machi, Chuo-ku, Kobe, Hyogo 650-0047 (Japan); Okada, Kensuke [RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5148 (Japan); Sugimoto, Takashi [JASRI, 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5198 (Japan); Yamaga, Mitsuhiro; Tanaka, Ryotaro [RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5148 (Japan); Yokokawa, Mitsuo; Hori, Atsushi [RIKEN Advanced Institute for Computational Science, 7-1-26 Minatojima-minami-machi, Chuo-ku, Kobe, Hyogo 650-0047 (Japan); Ishikawa, Yutaka, E-mail: ishikawa@is.s.u-tokyo.ac.jp [The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan); Hatsui, Takaki, E-mail: ishikawa@is.s.u-tokyo.ac.jp [RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5148 (Japan); Go, Nobuhiro [Japan Atomic Energy Agency, 8-1-7 Umemidai, Kizugawa, Kyoto 619-0215 (Japan)

2013-11-01

A code with an algorithm for high-speed classification of X-ray diffraction patterns has been developed. Results obtained for a set of 1 × 10{sup 6} simulated diffraction patterns are also reported. Single-particle coherent X-ray diffraction imaging using an X-ray free-electron laser has the potential to reveal the three-dimensional structure of a biological supra-molecule at sub-nanometer resolution. In order to realise this method, it is necessary to analyze as many as 1 × 10{sup 6} noisy X-ray diffraction patterns, each for an unknown random target orientation. To cope with the severe quantum noise, patterns need to be classified according to their similarities and average similar patterns to improve the signal-to-noise ratio. A high-speed scalable scheme has been developed to carry out classification on the K computer, a 10PFLOPS supercomputer at RIKEN Advanced Institute for Computational Science. It is designed to work on the real-time basis with the experimental diffraction pattern collection at the X-ray free-electron laser facility SACLA so that the result of classification can be feedback for optimizing experimental parameters during the experiment. The present status of our effort developing the system and also a result of application to a set of simulated diffraction patterns is reported. About 1 × 10{sup 6} diffraction patterns were successfully classificatied by running 255 separate 1 h jobs in 385-node mode.

What is the correct Fe L{sub 23} X-ray absorption spectrum of magnetite?

Energy Technology Data Exchange (ETDEWEB)

Zhu, Xiaohui; Kalirai, Samanbir S. [Department of Chemistry and Chemical Biology, McMaster University, Hamilton, ON L8S 4M1 (Canada); Hitchcock, Adam P., E-mail: aph@mcmaster.ca [Department of Chemistry and Chemical Biology, McMaster University, Hamilton, ON L8S 4M1 (Canada); Bazylinski, Dennis A. [School of Life Sciences, University of Nevada at Las Vegas, Las Vegas, NV 89154-4004 (United States)

2015-02-15

Highlights: • Fe L{sub 3} X-ray absorption spectra of biological (MV-1 magnetotactic bacteria) and abiotic (Sigma–Aldrich) nano-magnetite are reported. • An inconsistency in the literature for this spectrum is documented. • Powder diffraction shows the abiotic sample is partly oxidized, toward maghemite. • H{sub 2} thermal reduction converts the Fe L{sub 3} spectrum of the abiotic sample to that of the biotic. • Strong oxidation (air, 600 °C) is needed to convert the spectrum of the biotic magnetite to that of maghemite; magnetosome chains are protected by an air-impervious membrane. - Abstract: Various groups have reported Fe L{sub 23} X-ray absorption spectra (XAS) of magnetite (Fe{sub 3}O{sub 4}), each claiming to be that of magnetite, but which contradict each other. Here we report an XAS study of two kinds of magnetite: one is biogenic magnetite nanocrystals extracted from the magnetotactic bacterium Magnetovibrio blakemorei strain MV-1; the other is synthetic, abiogenically produced nano-magnetite. We see significantly different XAS spectra of these two materials. Only when the abiogenic magnetite was reduced under H{sub 2} did it give the same spectrum as the biogenic sample. Extensive heating of the biogenic magnetite in air produced spectra similar to that of the abiogenic magnetite. These two spectra are typical of the range of published Fe L{sub 23} spectra of magnetite. X-ray diffraction confirmed that the biogenic material is stoichiometric Fe{sub 3}O{sub 4}, and showed that the as-received or partly reduced abiogenic material is a non-stoichiometric oxide, intermediate between magnetite and maghemite (γ-Fe{sub 2}O{sub 3}). When the membrane which surrounds magnetosome chains was intact, the biotic magnetite single crystals were surprisingly resistant to oxidation. This study clarifies a significant confusion existing in the literature as to the correct Fe L{sub 23} X-ray absorption spectra of magnetite and maghemite.

Crystal structure and magnetic properties of La{sub 2−x}(Sr{sub 0.5}Ca{sub 0.5}){sub 1+x}Mn{sub 2}O{sub 7} (x=0.6, 0.8 and 1.0) Ruddlesden–Popper manganites

Energy Technology Data Exchange (ETDEWEB)

Raju, K.; Song, M.S.; Lee, J.Y., E-mail: jylee@yu.ac.kr

2014-05-01

Double layer perovskite (Ruddlesden–Popper) manganites with the nominal composition of La{sub 2−x}(Sr{sub 0.5}Ca{sub 0.5}){sub 1+x}Mn{sub 2}O{sub 7} (x=0.6, 0.8 and 1.0) were synthesized via a solid state reaction route. X-ray and neutron diffraction were performed at room temperature and the crystal structure was refined using the Rietveld method based on the space group, I4/mmm. The temperature variation of the susceptibility revealed a spin glass transition at 28 K for x=0.6, a charge ordering transition at 245 K and a Neel transition at 170 K for x=1.0. - Highlights: • Lanthanum based double layered manganites were prepared by doping with the same amounts of Sr and Ca. • X-ray and neutron diffraction were performed and the crystal structure was refined using the Rietveld method. • Different magnetic transitions were observed depending upon the doping concentration. • Qualitative explanation for the various observed phenomena was given.

Structure, chemistry and luminescence properties of dielectric La{sub x}Hf{sub 1-x}O{sub y} films

Energy Technology Data Exchange (ETDEWEB)

Kaichev, V.V., E-mail: vvk@catalysis.ru [Boreskov Institute of Catalysis, Novosibirsk (Russian Federation); Novosibirsk State University, Novosibirsk (Russian Federation); Smirnova, T.P.; Yakovkina, L.V. [Nikolaev Institute of Inorganic Chemistry, Novosibirsk (Russian Federation); Ivanova, E.V.; Zamoryanskaya, M.V. [Ioffe Physical-Technical Institute, St. Petersburg (Russian Federation); Saraev, A.A. [Boreskov Institute of Catalysis, Novosibirsk (Russian Federation); Novosibirsk State University, Novosibirsk (Russian Federation); Pustovarov, V.A. [Ural State Technical University, Ekaterinburg (Russian Federation); Perevalov, T.V.; Gritsenko, V.A. [Novosibirsk State University, Novosibirsk (Russian Federation); Rzhanov Institute of Semiconductor Physics, Novosibirsk (Russian Federation)

2016-06-01

Dielectric films of La{sub 2}O{sub 3}, HfO{sub 2}, and La{sub x}Hf{sub 1-x}O{sub y} were synthesized by metal-organic chemical vapor deposition. Structural, chemical, and luminescence properties of the films were studied using X-ray photoelectron spectroscopy, methods of X-ray diffraction and selected area electron diffraction, high-resolution transmission electron microscopy, and a cathodoluminescence technique. It was found that doping of hafnium oxide with lanthanum leads to the formation of a continuous series of solid solutions with a cubic structure. This process is accompanied by the formation of oxygen vacancies in the HfO{sub 2} lattice. Cathodoluminescence spectra of the La{sub x}Hf{sub 1-x}O{sub y}/Si films exhibited a wide band with the maximum near 2.4–2.5 eV, which corresponds to the blue emission. Quantum-chemical calculations showed that this blue band is due to oxygen vacancies in the HfO{sub 2} lattice. - Highlights: • HfO{sub 2} and solid solution La{sub x}Hf{sub 1-x}O{sub y} films were synthesized by MOCVD. • The continuous series of solid solutions with a cubic structure was formed at La doping of HfO{sub 2}. • Cathodoluminescence band at 2.4–2.5 eV is observed due to the oxygen vacancies in La{sub x}Hf{sub 1-x}O{sub y}. • The cathodoluminescence decreases in intensity when the La concentration increases.

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

Science.gov (United States)

Crouse, David T.

2007-01-01

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

The three dimensional X-ray diffraction technique

DEFF Research Database (Denmark)

Juul Jensen, Dorte; Poulsen, Henning Friis

2012-01-01

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

Advances in data reduction of high-pressure x-ray powder diffraction data from two-dimensional detectors: a case study of schafarzikite (FeSb{sub 2}O{sub 4})

Energy Technology Data Exchange (ETDEWEB)

Hinrichsen, B [Max-Planck-Institute for Solid State Research, Heisenbergstrasse 1, D-70569 Stuttgart (Germany); Dinnebier, R E [Max-Planck-Institute for Solid State Research, Heisenbergstrasse 1, D-70569 Stuttgart (Germany); Rajiv, P [Max-Planck-Institute for Solid State Research, Heisenbergstrasse 1, D-70569 Stuttgart (Germany); Hanfland, M [European Synchrotron Radiation Facility, 6 rue Jules Horowitz, BP220, 38043 Grenoble Cedex (France); Grzechnik, A [Departamento de Fisica de la Materia Condensada, Facultad de Ciencia y Technologia, Universidad del Pais Vasco, Apartado 644, E-48080 Bilbao (Spain); Jansen, M [Max-Planck-Institute for Solid State Research, Heisenbergstrasse 1, D-70569 Stuttgart (Germany)

2006-06-28

Methods have been developed to facilitate the data analysis of multiple two-dimensional powder diffraction images. These include, among others, automatic detection and calibration of Debye-Scherrer ellipses using pattern recognition techniques, and signal filtering employing established statistical procedures like fractile statistics. All algorithms are implemented in the freely available program package Powder3D developed for the evaluation and graphical presentation of large powder diffraction data sets. As a case study, we report the pressure dependence of the crystal structure of iron antimony oxide FeSb{sub 2}O{sub 4} (p{<=}21 GPa, T = 298 K) using high-resolution angle dispersive x-ray powder diffraction. FeSb{sub 2}O{sub 4} shows two phase transitions in the measured pressure range. The crystal structures of all modifications consist of frameworks of Fe{sup 2+}O{sub 6} octahedra and irregular Sb{sup 3+}O{sub 4} polyhedra. At ambient conditions, FeSb{sub 2}O{sub 4} crystallizes in space group P4{sub 2}/mbc (phase I). Between p = 3.2 GPa and 4.1 GPa it exhibits a displacive second order phase transition to a structure of space group P 2{sub 1}/c (phase II, a = 5.7792(4) A, b = 8.3134(9) A, c = 8.4545(11) A, {beta} = 91.879(10){sup 0}, at p = 4.2 GPa). A second phase transition occurs between p = 6.4 GPa and 7.4 GPa to a structure of space group P4{sub 2}/m (phase III, a = 7.8498(4) A, c = 5.7452(5) A, at p = 10.5 GPa). A nonlinear compression behaviour over the entire pressure range is observed, which can be described by three Vinet equations in the ranges from p = 0.52 GPa to p 3.12 GPa, p = 4.2 GPa to p = 6.3 GPa and from p = 7.5 GPa to p = 19.8 GPa. The extrapolated bulk moduli of the high-pressure phases were determined to K{sub 0} = 49(2) GPa for phase I, K{sub 0} = 27(3) GPa for phase II and K{sub 0} = 45(2) GPa for phase III. The crystal structures of all phases are refined against x-ray powder data measured at several pressures between p = 0.52 GPa

Structural study of CaMn{sub 1−x}Mo{sub x}O{sub 3} (0.08 ≤ x ≤ 0.12) system by neutron powder diffraction

Energy Technology Data Exchange (ETDEWEB)

Supelano, G.I., E-mail: ivan.supelano@uptc.edu.co [Grupo Física de Materiales, Escuela de Física, Universidad Pedagógica y Tecnológica de Colombia, Tunja (Colombia); Parra Vargas, C.A.; Barón-González, A.J. [Grupo Física de Materiales, Escuela de Física, Universidad Pedagógica y Tecnológica de Colombia, Tunja (Colombia); Sarmiento Santos, A. [Grupo Superficies Electroquímica y Corrosión, Escuela de Física, Universidad Pedagógica y Tecnológica de Colombia, Tunja (Colombia); Frontera, C. [Institut de Ciència de Materials de Barcelona, CSIC, Campus Universitari de Bellaterra, E-08193, Bellaterra, Barcelona (Spain)

2016-08-15

Neutron powder diffraction experiments and magnetic measurements in polycrystalline CaMn{sub 1−x}Mo{sub x}O{sub 3} (x = 0.08, 0.10, 0.12) point towards a possible charge and orbital order in this system. The analysis of structural and magnetic data show that the samples present structural phase transformation from Pnma to P2{sub 1}/m space group and the system has a C-type antiferromagnetic configuration at low temperature. A detailed analysis of the bond distances signals a small Jahn-Teller distortion of only one (x = 0.08) or of the two Mn ions (x = 0.10, 0.12). We identify the partially occupied e{sub g} orbitals and this explains the C-type magnetic structure. - Highlights: • CaMn{sub 1−x}Mo{sub x}O{sub 3} (x = 0.08, 0.10, 0.12) is investigated by neutron powder diffraction. • Analysis of individual Mn-O distances demonstrates the apparition of orbital order. • By symmetry analysis, we find that the low temperature magnetic structure is C-type. • Magnetic interactions foreseen by the orbital order explain the magnetic structure.

Synchrotron X-ray diffraction investigations on strains in the oxide layer of an irradiated Zircaloy fuel cladding

Energy Technology Data Exchange (ETDEWEB)

Chollet, Mélanie, E-mail: melanie.chollet@psi.ch [Paul Scherrer Institute, NES, 5232 Villigen (Switzerland); Valance, Stéphane; Abolhassani, Sousan; Stein, Gene [Paul Scherrer Institute, NES, 5232 Villigen (Switzerland); Grolimund, Daniel [Paul Scherrer Institute, SLS, 5232 Villigen (Switzerland); Martin, Matthias; Bertsch, Johannes [Paul Scherrer Institute, NES, 5232 Villigen (Switzerland)

2017-05-15

For the first time the microstructure of the oxide layer of a Zircaloy-2 cladding after 9 cycles of irradiation in a boiling water reactor has been analyzed with synchrotron micro-X-ray diffraction. Crystallographic strains of the monoclinic and to some extent of the tetragonal ZrO{sub 2} are depicted through the thick oxide layer. Thin layers of sub-oxide at the oxide-metal interface as found for autoclave-tested samples and described in the literature, have not been observed in this material maybe resulting from irradiation damage. Shifts of selected diffraction peaks of the monoclinic oxide show that the uniform strain produced during oxidation is orientated in the lattice and displays variations along the oxide layer. Diffraction peaks and their shifts from families of diffracting planes could be translated into a virtual tensor. This virtual tensor exhibits changes through the oxide layer passing by tensile or compressive components. - Highlights: •A Zircaloy-2 cladding irradiated 9 cycles was investigated thanks to synchrotron X-ray diffraction. •Microstructure and uniform strain through the oxide layer is revealed. •The m-ZrO{sub 2} uniform strain is oriented presenting compression along the (−111) plane. •Virtual tensor is built based on reflecting planes of families of grains. •Tensor components vary from tensile to compressive along the oxide layer.

Moessbauer and X-ray Study of Fe{sub 1-x}Al{sub x}, 0.2{<=}x{<=}0.5, Samples Produced by Mechanical Alloying

Energy Technology Data Exchange (ETDEWEB)

Oyola Lozano, D., E-mail: doyola@ut.edu.co; MartInez, Y. Rojas; Bustos, H.; Perez Alcazar, G. A. [Universidad del Tolima, Departamento de Fisica (Colombia)

2004-12-15

In this work we report the magnetic and structural properties obtained by Moessbauer spectroscopy and X-ray diffraction, of the Fe{sub 1-x}Al{sub x}, 0.2{<=}x{<=}0.5, alloys produced by mechanical alloying. Alloys with x=0.2, 0.3, 0.4 and 0.5, were for milled 12, 24, 36, and 48 hours. All the obtained alloys are in the bcc phase. The obtained Moessbauer spectra are characteristic of disordered ferromagnetic system. The lattice parameter remains nearly constant ({approx}2.91 A) for all the milling times and compositions. The mean grain sizes in the (110) and (211) direction are nearly constants with the milling time but vary from 15.5 to 11 nm and from 10.5 to 8.5 nm when Al content grow between x=0.2 to x=0.4, respectively. The difference between the mean grain sizes in these two directions shows that the grains are of prolate spheroid form.

Electronic properties of Nd{sub 2−x}Ce{sub x}CuO{sub 4+δ}: A hard X-ray photoemission investigation

Energy Technology Data Exchange (ETDEWEB)

Guarino, A., E-mail: guarino@sa.infn.it [CNR-SPIN-Salerno, Fisciano, SA (Italy); Dipartimento di Fisica “E. R. Caianiello” Università di Salerno, Fisciano, SA (Italy); Panaccione, G. [CNR-IOM Laboratorio TASC, AREA Science Park, 34012 Basovizza, TS (Italy); Offi, F. [CNISM and Dipartimento di Scienze, Università Roma Tre, Roma (Italy); Monaco, G. [Dipartimento di Fisica, Università di Trento, Trento (Italy); Fondacaro, A. [European Synchrotron Radiation Facility, BP 220, F-38042 Grenoble (France); Torelli, P. [CNR-IOM Laboratorio TASC, AREA Science Park, 34012 Basovizza, TS (Italy); Fittipaldi, R.; Vecchione, A. [CNR-SPIN-Salerno, Fisciano, SA (Italy); Pace, S.; Nigro, A. [CNR-SPIN-Salerno, Fisciano, SA (Italy); Dipartimento di Fisica “E. R. Caianiello” Università di Salerno, Fisciano, SA (Italy)

2016-10-15

Highlights: • We grow and characterize Nd{sub 2−x}Ce{sub x}CuO{sub 4+δ} samples as thin film and single crystal. • We study the Cu 2p levels of our samples by hard X-ray photoemission spectroscopy. • We investigate bulk features of the Nd{sub 2−x}Ce{sub x}CuO{sub 4+δ} samples. • Signature of the bulk response is correlated with the crystallinity of the samples. - Abstract: Cu 2p core levels spectra measured by X-ray photoemission spectroscopy of selected as-grown Nd{sub 2−x}Ce{sub x}CuO{sub 4+δ} samples are presented and discussed. The presence of a satellite peak in the 2p core level of Nd{sub 2−x}Ce{sub x}CuO{sub 4+δ} single crystal by hard X-ray photoemission is confirmed in all non-superconducting samples, films and single crystals investigated in this work. The comparison of the spectral features of the different samples suggests that the presence and the intensity of this satellite peak is not related to the electric transport properties, but to the texture characteristics.

Crystallization study of amorphous system Fe[sub 84-x]W[sub x]B[sub 16] (x = 3; 5)

Energy Technology Data Exchange (ETDEWEB)

Novakova, A.A.; Sidorova, G.V.; Kiseleva, T.Yu.; Szasz, A. (Dept. of Physics, State Univ., Moscow (Russia) Inst. of Metallurgy, Academy of Science, Moscow (Russia) Eoetvoes Univ., Budapest (Hungary))

1992-10-01

A complex study of the crystallization process of the amorphous system was carried out by Moessbauer spectroscopy, X-ray diffraction and DTA. Alloy samples crystallized at 600deg C contain the following phases: [alpha]-Fe, Fe[sub 3]B and solid solution (Fe, W)[sub 3]B. (orig.).

X-Ray Diffraction Project Final Report, Fiscal Year 2006

International Nuclear Information System (INIS)

Dane V. Morgan

2006-01-01

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

Induced 3d and 4f magnetism in Gd{sub 1-x}Pr{sub x}Ni{sub 2} Laves phase alloys

Energy Technology Data Exchange (ETDEWEB)

Bouziane, K [Department of Physics, College of Science, Sultan Qaboos University, PO Box 36, Al-Khodh 123 (Oman); Carboni, C [Department of Physics, College of Science, Sultan Qaboos University, PO Box 36, Al-Khodh 123 (Oman); Morrison, C [School of Physics and Astronomy, University of Southampton, Highfield, Southampton SO17 1BJ (United Kingdom)

2008-01-16

The series of Gd{sub 1-x}Pr{sub x}Ni{sub 2} (x = 0.25, 0.40, and 0.60) polycrystalline samples has been investigated using x-ray diffraction and magnetometry. The x-ray diffraction measurements showed that the lattice constant and the relative intensities of the C15 superstructure I{sub 511}/I{sub 440} and I{sub 511}/I{sub 220} increase with the praseodymium content, reflecting an increasing number of ordered vacancies at the 4a sites. The temperature dependences of the zero-field cooled (M{sub ZFC}(T)) and field cooled (M{sub FC}(T)) magnetizations show that a moment is induced by the gadolinium on the Pr{sup 3+} ion and on the nickel subsystem. In the ordered phase both induced moments are antiparallel to that of the Gd{sup 3+} ion. A cusp is observed at a temperature T{sub max} in the M{sub ZFC}(T) curve. Both critical temperatures T{sub c} and T{sub max} are found to decrease with increasing praseodymium content, indicating a reduction in strength of the antiparallel coupling for Gd-Pr and Gd-Ni pairs.

Induced magnetic anisotropy in Si-free nanocrystalline soft magnetic materials: A transmission x-ray diffraction study

Energy Technology Data Exchange (ETDEWEB)

Parsons, R., E-mail: rparsons01@gmail.com; Suzuki, K. [Department of Materials Science and Engineering, Monash University, Clayton, Victoria 3800 (Australia); Yanai, T. [Graduate School of Engineering, Nagasaki University, Nagasaki 852-8521 (Japan); Kishimoto, H.; Kato, A. [Toyota Motor Corporation, Mishuku, Susono, Shizuoka 410-1193 (Japan); Ohnuma, M. [Faculty and Graduate School of Engineering, Hokkaido University, Sapporo 060-8628 (Japan)

2015-05-07

In order to better understand the origin of field-induced anisotropy (K{sub u}) in Si-free nanocrystalline soft magnetic alloys, the lattice spacing of the bcc-Fe phase in nanocrystalline Fe{sub 94−x}Nb{sub 6}B{sub x} (x = 10, 12, 14) alloys annealed under an applied magnetic field has been investigated by X-ray diffraction in transmission geometry (t-XRD) with the diffraction vector parallel and perpendicular to the field direction. The saturation magnetostriction (λ{sub s}) of nanocrystalline Fe{sub 94−x}Nb{sub 6}B{sub x} was found to increase linearly with the volume fraction of the residual amorphous phase and is well described by taking into account the volume-weighted average of two local λ{sub s} values for the bcc-Fe nanocrystallites (−5 ± 2 ppm) and the residual amorphous matrix (+8 ± 2 ppm). The lattice distortion required to produce the measured K{sub u} values (∼100 J/m{sup 3}) was estimated via the inverse magnetostrictive effect using the measured λ{sub s} values and was compared to the lattice spacing estimations made by t-XRD. The lattice strain required to produce K{sub u} under the magnetoelastic model was not observed by the t-XRD experiments and so the findings of this study suggest that the origin of magnetic field induced K{sub u} cannot be explained through the magnetoelastic effect.

Precise rotational alignment of x-ray transmission diffraction gratings

International Nuclear Information System (INIS)

Hill, S.L.

1988-01-01

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

High resolution X-ray diffraction studies on unirradiated

Indian Academy of Sciences (India)

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

Diffractive-refractive optics: (+,-,-,+) X-ray crystal monochromator with harmonics separation.

Science.gov (United States)

Hrdý, Jaromír; Mikulík, Petr; Oberta, Peter

2011-03-01

A new kind of two channel-cut crystals X-ray monochromator in dispersive (+,-,-,+) position which spatially separates harmonics is proposed. The diffracting surfaces are oriented so that the diffraction is inclined. Owing to refraction the diffracted beam is sagittally deviated. The deviation depends on wavelength and is much higher for the first harmonics than for higher harmonics. This leads to spatial harmonics separation. The idea is supported by ray-tracing simulation.

Cloning, expression, purification, crystallization and preliminary X-ray diffraction analysis of the VP8* carbohydrate-binding protein of the human rotavirus strain Wa

Energy Technology Data Exchange (ETDEWEB)

Kraschnefski, Mark J.; Scott, Stacy A. [Institute for Glycomics, Griffith University (Gold Coast Campus), PMB 50 Gold Coast Mail Centre, Queensland 9726 (Australia); Holloway, Gavan; Coulson, Barbara S.; Itzstein, Mark von [Department of Microbiology and Immunology, The University of Melbourne, Victoria 3010 (Australia); Blanchard, Helen, E-mail: h.blanchard@griffith.edu.au [Institute for Glycomics, Griffith University (Gold Coast Campus), PMB 50 Gold Coast Mail Centre, Queensland 9726 (Australia)

2005-11-01

The carbohydrate-binding component (VP8*{sub 64–223}) of the human Wa rotavirus spike protein has been overexpressed in E. coli, purified and crystallized in two different crystal forms. X-ray diffraction data have been collected that have enabled determination of the Wa VP8*{sub 64–223} structure by molecular replacement. Rotaviruses exhibit host-specificity and the first crystallographic information on a rotavirus strain that infects humans is reported here. Recognition and attachment to host cells, leading to invasion and infection, is critically linked to the function of the outer capsid spike protein of the rotavirus particle. In some strains the VP8* component of the spike protein is implicated in recognition and binding of sialic-acid-containing cell-surface carbohydrates, thereby enabling infection by the virus. The cloning, expression, purification, crystallization and initial X-ray diffraction analysis of the VP8* core from human Wa rotavirus is reported. Two crystal forms (trigonal P3{sub 2}21 and monoclinic P2{sub 1}) have been obtained and X-ray diffraction data have been collected, enabling determination of the VP8*{sub 64–223} structure by molecular replacement.

X-ray diffraction analysis of InAs nanowires

International Nuclear Information System (INIS)

Davydok, Anton

2013-01-01

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

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

DEFF Research Database (Denmark)

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

2009-01-01

Non-destructive, three-dimensional (3D) characterization of the grain structure in mono-phase polycrystalline materials is an open challenge in material science. Recent advances in synchrotron based X-ray imaging and diffraction techniques offer interesting possibilities for mapping 3D grain shapes....... A recent extension of this methodology, termed X-ray diffraction contrast tomography (DCT), combines the principles of X-ray diffraction imaging, three-dimensional X-ray diffraction microscopy (3DXRD) and image reconstruction from projections. DCT provides simultaneous access to 3D grain shape...

STM and x-ray diffraction temperature-dependent growth study of SrRuO{sub 3} PLD thin films

Energy Technology Data Exchange (ETDEWEB)

Hawley, M.E.; Jia, Q.X.; Brown, G.W.

1996-12-31

SrRuO{sub 3} (SRO) has recently found a number of applications in different fields, e.g. as a buffer layer for the growth of high temperature superconductor (HTS) YBa{sub 2}Cu{sub 3}O{sub 7-x} films and as a bottom electrode for ferroelectric or high dielectric constant thin film capacitors and nonvolatile data storage. The growth of high crystallinity SRO films with good structural and electrical properties is the prerequisite for each of these applications. In this paper we describe the affect of one growth parameters temperature (T), on the crystalline quality, epitaxial substrate relationship and resulting electrical properties. SRO films were deposited on LaAlO{sub 3} single crystal substrates by pulsed laser deposition at substrate temperatures (T{sub s}) ranging from room temperature (RT) up to 800{degrees}C with a nominal film thickness of 150 nm range. The resulting films were characterized by x-ray diffraction, 4-point transport, and STM. The films` microstructures, as revealed by STM, evolved from polygranular at RT to a layered plate-like structure at higher deposition temperatures, T{sub s}, Increasing T{sub s} was marked first by increasing grain size, then a stronger orientational relationship between film and substrate, finally followed by the development of increased connectivity between grains to an extended island or condensed layered state. The transition from polygranular to layered structure occurred at T{sub s} > 650{degrees}C. Increased conductivity paralleled the changes in microstructure. The surfaces of all of the films were relatively smooth; the oriented films are suitable for use as conductive templates in multilayer structures.

Synthesis and characterization of the double perovskite BaSrCoFe{sub 1}-{sub x}Ni{sub x}O{sub 5.5} like cathode for solid oxide fuel cells; Sintesis y caracterizacion de la doble perovskita BaSrCoFe{sub 1}-{sub x}Ni{sub x}O{sub 5.5} como catodo para celdas SOFC

Energy Technology Data Exchange (ETDEWEB)

Alvarado F, J.; Avalos R, L.; Viramontes G, G. [Universidad Michoacana de San Nicolas de Hidalgo, Facultad de Ingenieria Electrica, Santiago Tapia 403, Morelia 58030, Michoacan (Mexico); Reyes R, A. [Centro de Investigacion en Materiales Avanzados, Laboratorio Nacional de Nanotecnologia, Miguel de Cervantes 120, Complejo Industrial Chihuahua, Chihuahua 31109, Chihuahua (Mexico)

2013-08-01

Have been synthesized via sol-gel method and characterized by X-ray diffraction, electrical conductivity and thermal expansion coefficient, new material composites BaSrCoFe{sub 1{sub x}}Ni{sub x}O{sub 5.5} (double perovskite type) with the addition of Ni in solid solution Ni{sub x} (x = 0.025, 0.05, 0.075, 0.1 and 0.2), as alternative cathodes for solid oxide fuel cells of intermediate temperature (Sofc-It). X-ray diffraction confirmed the formation of the tetragonal structure perovskite phase BaSrCoFe{sub 1}-{sub x}Ni{sub x}O{sub 5.5}, with the presence of small peaks identified in 2{theta} values below 30 degrees as BaCO{sub 3} and CoFe{sub 2}O{sub 4}. The electrical conductivity increases with the temperature between 350-470 degrees C and then decreases due to the loss of oxygen in the net, which causes differences in conductivity. Semiconductor behavior was obtained in all compositions. Thermal expansion coefficient determination, showed a linear dependence inversely proportional to the concentration of Ni. Our results of electrical conductivity and thermal expansion coefficient, reach to the conclusion that the cathodes between 0.1 and 0.2 Ni, have the greatest possibility for application in Sofc-It. (Author)

Structural investigation of GaInP nanowires using X-ray diffraction

DEFF Research Database (Denmark)

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

2013-01-01

In this work the structure of ternary GaxIn1−xP nanowires is investigated with respect to the chemical composition and homogeneity. The nanowires were grown by metal–organic vapor-phase epitaxy. For the investigation of ensemble fluctuations on several lateral length scales, X-ray diffraction...... gradients along the sample by recording diffraction patterns at different positions. In addition, compositional variations were found also within single nanowires in X-ray energy dispersive spectroscopy measurements....

Basic of X-ray diffraction

International Nuclear Information System (INIS)

Giacovazzo, C.

1996-01-01

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

Basic of X-ray diffraction

Energy Technology Data Exchange (ETDEWEB)

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

1996-09-01

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

Residual stress characterization of welds using x-ray diffraction techniques

International Nuclear Information System (INIS)

Pineault, J.A.; Brauss, M.E.

1996-01-01

Neglect of residual stresses created during processes lead to stress corrosion cracking, distortion, fatigue cracking, premature failures in components, and instances of over design. Automated residual stress mapping and truly portable equipment have now made the characterization of residual stresses using x-ray diffraction (XRI) practical. The nondestructive nature of the x-ray diffraction technique has made the tile residual stress characterization of welds a useful tool for process optimization and failure analysis, particularly since components can be measured before and after welding and post welding processes. This paper illustrates the importance of residual stress characterization in welds and presents examples where x-ray diffraction techniques were applied in the characterization of various kinds of welds. arc welds, TIG welds, resistance welds, laser welds and electron beam welds. Numerous techniques are available to help manage potentially harmfull residual stresses created during the welding process thus, the effects of a few example post weld processes such as grinding, heat treating and shot peening are also addressed

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

Science.gov (United States)

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

2017-09-01

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

X-ray diffraction analysis of thermally-induced stress relaxation in ZnO films deposited by magnetron sputtering on (100) Si substrates

Energy Technology Data Exchange (ETDEWEB)

Conchon, F., E-mail: florineconchon@gmail.co [Laboratoire de Physique des Materiaux (PHYMAT) UMR 6630, Universite de Poitiers, 86962 Futuroscope-Chasseneuil (France); Renault, P.O.; Goudeau, P.; Le Bourhis, E. [Laboratoire de Physique des Materiaux (PHYMAT) UMR 6630, Universite de Poitiers, 86962 Futuroscope-Chasseneuil (France); Sondergard, E.; Barthel, E.; Grachev, S. [Laboratoire de Surface du Verre et Interfaces (SVI), UMR 125, 93303 Aubervilliers (France); Gouardes, E.; Rondeau, V.; Gy, R. [Laboratoire de Recherche de Saint-Gobain (SGR), 93303 Aubervilliers (France); Lazzari, R.; Jupille, J. [Institut des Nanosciences de Paris (INSP), UMR 7588, 75015 Paris (France); Brun, N. [Laboratoire de Physique des Solides (LPS), UMR 8502, 91405 Orsay (France)

2010-07-01

Residual stresses in sputtered ZnO films on Si are determined and discussed. By means of X-ray diffraction, we show that as-deposited ZnO films are highly compressively stressed. Moreover, a transition of stress is observed as a function of the post-deposition annealing temperature. After an 800 {sup o}C annealing, ZnO films are tensily stressed while ZnO films encapsulated by Si{sub 3}N{sub 4} are stress-free. With the aid of in-situ X-ray diffraction under ambient and argon atmosphere, we argue that this thermally activated stress relaxation may be attributed to a variation of the stoichiometry of the ZnO films.

Magnetic behaviour governed by Co spin transitions in LaCo{sub 1-x}Ti{sub x}O{sub 3} (0 {<=} x {<=} 0.5) perovskite oxides

Energy Technology Data Exchange (ETDEWEB)

Alvarez-Serrano, I; Lopez, M L; Pico, C; RodrIguez, E; Veiga, M L [Departamento de Quimica Inorganica I, Facultad de Ciencias Quimicas, Universidad Complutense, 28040 Madrid (Spain); Cuello, G J [Institut Max von Laue-Paul Langevin (ILL), 38042 Grenoble Cedex 9 (France); Jimenez-Lopez, A; RodrIguez-Castellon, E [Departamento de Quimica Inorganica, CristalografIa y MineralogIa, Facultad de Ciencias, Universidad de Malaga, 29071 Malaga (Spain)], E-mail: marisal@quim.ucm.es

2008-10-07

Perovskite-type cobaltites LaCo{sub 1-x}Ti{sub x}O{sub 3} (0 {<=} x {<=} 0.5) synthesized by the liquid mix technique were characterized by x-ray diffraction, neutron diffraction, XPS, magnetic susceptibility and magnetization versus magnetic field measurements. Structural symmetry changes from rhombohedral (S.G. R 3-bar c) for 0.05 {<=} x {<=} 0.20 to orthorhombic (S.G. Pbnm) for 0.25 {<=} x {<=} 0.40. The bond distances dependence on the composition, x, has been analysed from x-ray and neutron diffraction data. Both the structural and the spectroscopic (from XPS) results suggest that Ti{sup 4+} substitution implies the stabilization of low-spin Co{sup III} ions and the evolution of magnetic moments in the paramagnetic zone is also coherent with this assumption. For small values of x both FM responses and the absence of saturation in the M versus H curves at 2 K are interpreted in terms of a magnetic frustration. For x > 0.25 the cobalt cations seem to stabilize as Co{sup III} (rather than Co{sup 3+}) coexisting with Co{sup 2+}. In these more substituted perovskites, AFM Co{sup 2+}-O-Co{sup 2+} interactions become predominant, leading to a well established AFM ordering for x = 0.4 and 0.5.

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

International Nuclear Information System (INIS)

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

2014-01-01

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 0.67 Sr 0.33 MnO 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

Neutron powder diffraction investigation on the crystal and magnetic structure of (Ho{sub 0.50+x}Ca{sub 0.50-x})(Mn{sub 1-x}Cr{sub x})O{sub 3}

Energy Technology Data Exchange (ETDEWEB)

Martinelli, A; Ferretti, M [SPIN-CNR, Corso Perrone 24, 16152 Genova (Italy); Castellano, C [Dipartimento di Chimica Strutturale e Stereochimica Inorganica, Universita degli Studi di Milano, Via C Venezian 21, 20133 Milano (Italy); Cimberle, M R; Masini, R [IMEM-CNR, Via Dodecaneso 33, 16146 Genova (Italy); Ritter, C, E-mail: alberto.martinelli@spin.cnr.it [Institute Laue-Langevin, 6 rue Jules Horowitz, 38042 Grenoble Cedex 9 (France)

2011-10-19

The crystal and magnetic structure of (Ho{sub 0.50+x}Ca{sub 0.50-x})(Mn{sub 1-x}Cr{sub x})O{sub 3} (x = 0.00, 0.01, 0.02, 0.03) has been investigated between 5 and 300 K by means of neutron powder diffraction followed by Rietveld refinement and dc magnetic measurements. During cooling an orthorhombic to monoclinic phase transition occurs on account of the charge and orbital ordering taking place in the Mn sub-lattice; at low temperature phase separation takes place and the main monoclinic phase coexists with a secondary orthorhombic phase, whose amount slightly increases with the increase of Cr content. Cr{sup 3+} is not involved in orbital ordering or superexchange interactions. The charge and magnetic ordering are decoupled: the Mn moments order according to a CE-type structure in all samples. (paper)

X-ray diffraction studies of chitosan acetate-based polymer electrolytes

International Nuclear Information System (INIS)

Osman, Z.; Ibrahim, Z.A.; Abdul Kariem Arof

2002-01-01

Chitosan is the product when partially deacetylated chitin dissolves in dilute acetic acid. This paper presents the x-ray diffraction patterns of chitosan acetate, plasticised chitosan acetate and plasticised-salted chitosan acetate films. The results show that the chitosan acetate based polymer electrolyte films are not completely amorphous but it is partially crystalline. X-ray diffraction study also confirms the occurrence of the complexation between chitosan and the salt and the interaction between salt and plasticizer. The salt-chitosan interaction is clearly justified by infrared spectroscopy. (Author)

Contained x-ray diffraction goniometer for examination of radioactive materials

International Nuclear Information System (INIS)

Smith, P.K.; Osgood, B.C.; Blaser, D.E.; Howell, R.E.; Stuhler, H.; Stauver, J.

1987-11-01

Radioactive materials are being characterized for chemical form and certain physical properties with an x-ray diffraction goniometer customized for containment in a shielded alpha glovebox. A Siemens D500 goniometer was customized by Siemens to locate the associated electronics and x-ray generator outside the glovebox to minimize corrosion and facilitate maintenance. A graphite monochromator is used with a shielded scintillation detector to separate diffracted x-radiation from nuclear radiation. The diffraction system is computer automated for data acquisition and reduction. The facility is designed to handle primarily alpha- and beta-emitting samples with moderate neutron and gamma radiation. Samples containing plutonium, enriched uranium, and other transuranic elements are analyzed in support of site nuclear operations and development programs on nuclear waste, chemical separations, reactor fuels, and product forms

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

Directory of Open Access Journals (Sweden)

Yoshifuru Mitsui, Keiichi Koyama and Kazuo Watanabe

2009-01-01

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

A differential scanning calorimetric and X-ray diffraction

Indian Academy of Sciences (India)

X-ray diffraction analysis of the two groups demonstrated predominance of austenitic ... Discrete crystallographic structure and absence of multiple phases showed ... Division of Orthodontics, Indian Army, 10 Corps Dental Unit, C/O 56 APO, ...

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

International Nuclear Information System (INIS)

Bruegemann, Lutz; Gerndt, E.K.E.

2004-01-01

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

Discovery and development of x-ray diffraction

Science.gov (United States)

Jeong, Yeuncheol; Yin, Ming; Datta, Timir

2013-03-01

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

High magnetic ordering temperature in the perovskites Sr{sub 4-x}La{sub x}Fe{sub 3}ReO{sub 12} (x=0.0, 1.0, 2.0)

Energy Technology Data Exchange (ETDEWEB)

Retuerto, M.; Li, M.-R.; Go, Y.B. [Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, 610 Taylor Road, Piscataway, NJ 08854 (United States); Ignatov, A.; Croft, M. [Department of Physics and Astronomy, Rutgers, The State University of New Jersey, 136 Frelinghuysen Road, Piscataway, NJ 08854 (United States); Ramanujachary, K.V. [Department of Chemistry and Physics, Rowan University, 210 Mullica Hill Road, Glassboro, NJ 08028 (United States); Herber, R.H.; Nowik, I. [Racah Institute of Physics, Hebrew University, Jerusalem, 91904 Israel (Israel); Hodges, J.P. [Spallation Neutron Source, Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States); Dachraoui, W.; Hadermann, J. [EMAT, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp (Belgium); Greenblatt, M., E-mail: martha@rutchem.rutgers.edu [Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, 610 Taylor Road, Piscataway, NJ 08854 (United States)

2012-10-15

A series of perovskites Sr{sub 4-x}La{sub x}Fe{sub 3}ReO{sub 12} (x=0.0, 1.0, 2.0) has been prepared by wet chemistry methods. The structure analyses by powder X-ray and neutron diffraction and electron microscopy show that these compounds adopt simple perovskite structures without cation ordering over the B sites: tetragonal (I4/mcm) for x=0.0 and 1.0 and orthorhombic (Pbmn) for x=2.0. The oxidation states of the cations in the compound with x=0.0 appear to be Fe{sup 3+/4+} and Re{sup 7+} and decrease for both with La substitution as evidenced by X-ray absorption spectroscopy. All the compounds are antiferromagnetically ordered above room temperature, as demonstrated by Moessbauer spectroscopy and the magnetic structures, which were determined by powder neutron diffraction. The substitution of Sr by La strongly affects the magnetic properties with an increase of T{sub N} up to {approx}750 K. - Graphical abstract: High resolution transmission electron microscopy image of Sr{sub 4-x}La{sub x}Fe{sub 3}ReO{sub 12} (x=2.0), showing twin domains. Fourier transforms are given of the areas indicated by the circles. Highlights: Black-Right-Pointing-Pointer Sr{sub 4-x}La{sub x}Fe{sub 3}ReO{sub 12} (x=0.0, 1.0, 2.0) perovskites prepared by wet chemistry. Black-Right-Pointing-Pointer PXD, PND, ED, indicate no cation ordering, I4/mcm) for x=0.0, 1.0, Pbmn for x=2. Black-Right-Pointing-Pointer XAS show oxidation states Fe{sup 3+/4+} and Re{sup 7+}; both decrease with increasing x. Black-Right-Pointing-Pointer All order antiferromagnetically above RT, with highest T{sub N} {approx}750 K.

Thermal dehydration of potash alum studied by Raman spectroscopy and X-ray diffraction analysis

Energy Technology Data Exchange (ETDEWEB)

Kishimura, Hiroaki, E-mail: kisimura@nda.ac.jp; Imasu, Yuhta; Matsumoto, Hitoshi

2015-01-15

The thermal dehydrations of potash alum caused by heating at various temperatures for at least 2 h were investigated by ex situ Raman spectroscopy and X-ray diffraction (XRD) analyses in air. With increasing the heating temperature, all Raman peaks were observed to broaden, while an additional broad peak appeared at approximately 1030 cm{sup −1} and shifted toward higher wavenumbers. In addition, the Raman band assigned to the O–H stretching mode weakened. The orientational disorder (OD) of the sulfate ions, as indicated by the intensity ratio of doublet peaks at 989 and 974 cm{sup −1}, was found to increase with increasing the heating temperature. The XRD patterns demonstrated that a structural phase transition from crystalline KAl(SO{sub 4}){sub 2}⋅12H{sub 2}O to amorphous phases began at around 75 °C, while broadening of the Raman peaks and an increase in OD also suggested the onset of an amorphous phase. Raman peaks corresponding to anhydrous KAl(SO{sub 4}){sub 2} appeared at approximately 180 °C. It was concluded that the elimination of water molecules was responsible for increase in the extent of OD, and this in turn induced the observed phase transitions. The formation of the amorphous phases observed in this work was similar to the pressure-induced amorphization of KAl(SO{sub 4}){sub 2}⋅12H{sub 2}O. - Highlights: • The thermal dehydration of potash alum proceeds through several steps. • Raman spectra and X-ray diffraction reveal the amorphization of the heated samples. • A transition from the amorphous phase to the KAl(SO{sub 4}){sub 2} crystal phase is observed in the sample heated at 180 °C.

Absence of intrinsic ferromagnetism in Zn{sub 1-x}Mn{sub x}O alloys

Energy Technology Data Exchange (ETDEWEB)

Zhang Huawei [Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050 (China); Shi Erwei [Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050 (China); Chen Zhizhan [Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050 (China); Liu Xuechao [Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050 (China); Xiao Bing [Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050 (China)

2006-10-04

Zn{sub 1-x}Mn{sub x}O alloys, with different Mn concentrations, were prepared by the hydrothermal method. X-ray diffraction and electron paramagnetic resonance spectra demonstrate that Zn{sup 2+} ions are homogeneously substituted by Mn{sup 2+} ions without changing the ZnO wurtzite structure. The x = 0.02 and 0.04 samples are paramagnetic. When the Mn concentrations are increased to x = 0.08 and 0.10, the samples exhibit some ferromagnetism due to a secondary phase (Zn,Mn)Mn{sub 2}O{sub 4}. (letter to the editor)

IL 12: Femtosecond x-ray powder diffraction

International Nuclear Information System (INIS)

Woerner, M.; Zamponi, F.; Rothhardt, P.; Ansari, Z.; Dreyer, J.; Freyer, B.; Premont-Schwarz, M.; Elsaesser, T.

2010-01-01

A chemical reaction generates new compounds out of one or more initial species. On a molecular level, the spatial arrangement of electrons and nuclei changes. While the structure of the initial and the product molecules can be measured routinely, the transient structures and molecular motions during a reaction have remained unknown in most cases. This knowledge, however, is a key element for the exact understanding of the reaction. The ultimate dream is a 'reaction microscope' which allows for an in situ imaging of the molecules during a reaction. We report on the first femtosecond x-ray powder diffraction experiment in which we directly map the transient electronic charge density in the unit cell of a crystalline solid with 30 pico-meter spatial and 100 femtosecond temporal resolution. X-ray diffraction from polycrystalline powder samples, the Debye Scherrer diffraction technique, is a standard method for determining equilibrium structures. The intensity of the Debye Scherrer rings is determined by the respective x-ray structure factor which represents the Fourier transform of the spatial electron density. In our experiments, the transient intensity and angular positions of up to 20 Debye Scherrer reactions from a polycrystalline powder are measured and unravel for the first time a concerted electron and proton transfer in hydrogen-bonded ionic (NH 4 ) 2 SO 4 crystals. Photoexcitation of ammonium sulfate induces a sub-100 fs electron transfer from the sulfate groups into a highly conned electron channel along the z-axis of the unit cell. The latter geometry is stabilized by transferring protons from the adjacent ammonium groups into the channel. Time-dependent charge density maps derived from the diffraction data display a periodic modulation of the channels charge density by low-frequency lattice motions with a concerted electron and proton motion between the channel and the initial proton binding site. A deeper insight into the underlying microscopic

Expression, purification and preliminary X-ray diffraction studies of the transcriptional factor PyrR from Bacillus halodurans

Energy Technology Data Exchange (ETDEWEB)

Arreola, Rodrigo [Departamento de Bioquímica, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Circuito Exterior s/n, Ciudad Universitaria, Apartado Postal 70-243, Mexico City 04510 (Mexico); Vega-Miranda, Anita [Instituto Nacional de Enfermedades Respiratorias, Calzada de Tlalpan 4502, México DF 14080 (Mexico); Gómez-Puyou, Armando; Pérez-Montfort, Ruy [Departamento de Bioquímica, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Circuito Exterior s/n, Ciudad Universitaria, Apartado Postal 70-243, Mexico City 04510 (Mexico); Merino-Pérez, Enrique [Departamento de Microbiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Apartado Postal 510-3, Cuernavaca, Morelos (Mexico); Torres-Larios, Alfredo, E-mail: torres@ifc.unam.mx [Departamento de Bioquímica, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Circuito Exterior s/n, Ciudad Universitaria, Apartado Postal 70-243, Mexico City 04510 (Mexico)

2008-08-01

The gene-regulation factor PyrR from B. halodurans has been crystallized in two crystal forms. Preliminary crystallographic analysis showed that the protein forms tetramers in both space groups. The PyrR transcriptional regulator is widely distributed in bacteria. This RNA-binding protein is involved in the control of genes involved in pyrimidine biosynthesis, in which uridyl and guanyl nucleotides function as effectors. Here, the crystallization and preliminary X-ray diffraction analysis of two crystal forms of Bacillus halodurans PyrR are reported. One of the forms belongs to the monoclinic space group P2{sub 1} with unit-cell parameters a = 59.7, b = 87.4, c = 72.1 Å, β = 104.4°, while the other form belongs to the orthorhombic space group P22{sub 1}2{sub 1} with unit-cell parameters a = 72.7, b = 95.9, c = 177.1 Å. Preliminary X-ray diffraction data analysis and molecular-replacement solution revealed the presence of four and six monomers per asymmetric unit; a crystallographic tetramer is formed in both forms.

Glancing angle synchrotron X-ray diffraction

Energy Technology Data Exchange (ETDEWEB)

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

1996-09-01

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

Glancing angle synchrotron X-ray diffraction

International Nuclear Information System (INIS)

Cernik, R.J.

1996-01-01

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

Design and fabrication of micro X-ray diffraction system

International Nuclear Information System (INIS)

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

2006-10-01

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

Design and fabrication of micro X-ray diffraction system

Energy Technology Data Exchange (ETDEWEB)

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

2006-10-15

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

Determination of densities from chemical composition and X-Ray diffraction

International Nuclear Information System (INIS)

Azevedo, A.L.T. de

1980-01-01

X-ray diffraction method applied to retained austenite measurements gives volume per cent results, whereas the same kind of measurement made by Moessbauer Effect gives iron percentages. To compare both results one needs to convert the volume % to weight % or vice-versa. This necessitates, among other things, in determining the densities of the α and #betta# phases in the steel being studied. A method for calculating the densities, based on the application of the definition of density to just one unit cell, using X-ray diffraction and chemical results, are described. (Author) [pt

Magnetic x-ray circular dichroism in spin-polarized photoelectron diffraction

International Nuclear Information System (INIS)

Waddill, G.D.; Tobin, J.G.

1994-01-01

The first structural determination with spin-polarized, energy-dependent photoelectron diffraction using circularly-polarized x-rays is reported for Fe films on Cu(001). Circularly-polarized x-rays produced spin-polarized photoelectrons from the Fe 2p doublet, and intensity asymmetries in the 2p 3/2 level are observed. Fully spin-specific multiple scattering calculations reproduced the experimentally-determined energy and angular dependences. A new analytical procedure which focuses upon intensity variations due to spin-dependent diffraction is introduced. A sensitivity to local geometric and magnetic structure is demonstrated

High-energy X-ray diffraction studies of short- and intermediate-range structure in oxide glasses

International Nuclear Information System (INIS)

Suzuya, Kentaro

2002-01-01

The feature of high-energy X-ray diffraction method is explained. The oxide glasses studies by using BL04B2, high-energy X-ray diffraction beam line of SPring-8, and the random system materials by high-energy monochromatic X-ray diffraction are introduced. An advantage of third generation synchrotron radiation is summarized. On SPring-8, the high-energy X-ray diffraction experiments of random system are carried out by BL04B2 and BL14B1 beam line. BL04B2 can select Si (111)(E=37.8 keV, λ=0.033 nm) and Si(220)(E=61.7 keV, λ=0.020 nm) as Si monochromator. The intermediate-range structure of (MgO) x (P 2 O 5 ) 1-x glass ,MgP 2 O 6 glass, B 2 O 3 glass, SiO 2 and GeO 2 are explained in detail. The future and application of high-energy X-ray diffraction are stated. (S.Y.)

Room temperature ferromagnetism in Th{sub 1-x}Fe{sub x}O{sub 2-{delta}} (x = 0.0, 0.05, 0.10, 0.15, 0.20 and 0.25) nanoparticles

Energy Technology Data Exchange (ETDEWEB)

Jayakumar, O.D. [Chemistry Division, Bhabha Atomic Research Centre, Mumbai 400085 (India); Gopalakrishnan, I.K. [Chemistry Division, Bhabha Atomic Research Centre, Mumbai 400085 (India)], E-mail: ikgopal@barc.gov.in; Vinu, A. [Nano-Ionics Materials Group, Fuel Cell Materials Center, National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044 (Japan); Asthana, A. [Advanced Electron Microscopy Group, National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044 (Japan); Tyagi, A.K. [Chemistry Division, Bhabha Atomic Research Centre, Mumbai 400085 (India)

2008-08-11

Nanocrystalline (Th{sub 1-x}Fe{sub x})O{sub 2-{delta}} particles with different Fe concentrations (x = 0.0, 0.05, 0.10, 0.15, 0.20 and 0.25) have been prepared by a gel combustion method. Rietveld refinement analyses of X-ray diffraction data revealed the formation of an impurity free cubic type Th{sub 1-x}Fe{sub x}O{sub 2-{delta}} structure up to x = 0.20. This observation is further confirmed from the detailed studies conducted on 10 at.% Fe doped ThO{sub 2} using high-resolution transmission electron microscopy (HRTEM) imaging and indexing of the selected-area electron diffraction (SAED) patterns. DC magnetization studies as a function field indicate that they are ferromagnetic with Curie temperature (T{sub c}) well above room temperature.

X-ray diffraction studies of NbTe2 single crystal

Indian Academy of Sciences (India)

Unknown

X-ray (EDAX) and remaining structural characterization was also accomplished by X-ray diffraction (XRD) studies. Lattice parameters, volume and ... The layered structure compound, NbTe2, is one of the typical materials which lead to charge .... financial assistance to carry out this work. References. Brown B E 1966 Acta ...

Enhanced photocatalysis, colloidal stability and cytotoxicity of synchrotron X-ray synthesized Au/TiO{sub 2} nanoparticles

Energy Technology Data Exchange (ETDEWEB)

Liu, Chi-Jen; Yang, Tsung-Yeh; Wang, Chang-Hai [Institute of Physics, Academia Sinica, Nankang, Taipei 115, Taiwan (China); Chien, Chia-Chi [Institute of Physics, Academia Sinica, Nankang, Taipei 115, Taiwan (China); Department of Engineering Science and System, National Tsing Hua University, Hsinchu 300, Taiwan (China); Chen, Shin-Tai; Wang, Cheng-Liang; Leng, Wei-Hua [Institute of Physics, Academia Sinica, Nankang, Taipei 115, Taiwan (China); Hwu, Y., E-mail: phhwu@sinica.edu.tw [Institute of Physics, Academia Sinica, Nankang, Taipei 115, Taiwan (China); Department of Engineering Science and System, National Tsing Hua University, Hsinchu 300, Taiwan (China); Institute of Optoelectronic Sciences, National Taiwan Ocean University, Keelung 202, Taiwan (China); National Synchrotron Radiation Research Center, Hsinchu 300, Taiwan (China); Lin, Hong-Ming [Department of Materials Engineering, Tatung University, Taipei 10461, Taiwan (China); Lee, Yao-Chang [National Synchrotron Radiation Research Center, Hsinchu 300, Taiwan (China); Cheng, Chia-Liang [Department of Physics, National Dong Hwa University, Hualien 97401, Taiwan (China); Je, J.H. [X-ray Imaging Center, Pohang University of Science and Technology, Pohang (Korea, Republic of); Margaritondo, G. [Ecole Polytechnique Federale de Lausanne (EPFL), CH-1015 Lausanne (Switzerland)

2009-09-15

Au/TiO{sub 2} nanocomposite particles were synthesized by a method based on intense X-ray irradiation without adding any reducing agent or stabilizer. The nanocomposite exhibits promising photocatalytic and biological properties at physiologically relevant concentration ([Au] = 0.028 mM, [TiO{sub 2}] = 0.5 mM). The structure and photocatalysis were examined by X-ray diffraction, electron microscopy and ultraviolet-visible spectroscopy demonstrating that gold nanoparticles of 2-5 nm size were successfully deposited on TiO{sub 2} nanoparticle surfaces. The nanocomposite exhibited good colloidal stability within a typical cellular environment and was nontoxic to cancer cell according to evaluations under controlled conditions. The Au/TiO{sub 2} nanoparticles were also found to enhance the photocatalytic efficiency of UV radiation and even more that of X-ray radiation. In vitro studies indicated that the cell-killing effect under X-ray irradiation is more pronounced with the addition of Au/TiO{sub 2} nanoparticles than of bare TiO{sub 2} nanoparticles.

Crystallization and preliminary X-ray diffraction study of recombinant ribokinase from Thermus Species 2.9

Energy Technology Data Exchange (ETDEWEB)

Abramchik, Yu. A. [Russian Academy of Sciences, Shemyakin–Ovchinnikov Institute of Bioorganic Chemistry (Russian Federation); Timofeev, V. I., E-mail: tostars@mail.ru [Russian Academy of Sciences, Shubnikov Institute of Crystallography of Federal Scientific Research Centre “Crystallography and Photonics,” (Russian Federation); Muravieva, T. I.; Esipov, R. S., E-mail: espiov@mx.ibch.ru [Russian Academy of Sciences, Shemyakin–Ovchinnikov Institute of Bioorganic Chemistry (Russian Federation); Kuranova, I. P., E-mail: inna@ns.crys.ras.ru [Russian Academy of Sciences, Shubnikov Institute of Crystallography of Federal Scientific Research Centre “Crystallography and Photonics,” (Russian Federation)

2016-11-15

Ribokinase from a thermophilic strain of Thermus species 2.9 belonging to the carbohydrate ribokinase family (EC 2.7.1.15) was isolated, purified, and crystallized. The crystallization conditions were found by the vapor-diffusion technique and were then optimized to apply the capillary counter-diffusion technique. The X-ray diffraction data set was collected from the crystals, which were grown by the counter-diffusion technique, at the SPring-8 synchrotron radiation facility to 2.87 Å resolution. The crystals belong to sp. gr. P12{sub 1}1 and have the following unit-cell parameters: a = 81.613 Å, b = 156.132 Å, c = 87.714 Å, α = γ = 90°, β = 103.819°. The X-ray diffraction data set is suitable for determining the three-dimensional structure of the protein by the molecular-replacement method.

Facile synthesis of Ba<sub>1-xK_{x>Fe₂As₂ superconductors via hydride route}

Energy Technology Data Exchange (ETDEWEB)

Zaikina, Julia V. [Univ. of California at Davis, Davis, CA (United States); Batuk, Maria [Univ. of Antwerp, Antwerp (Belgium); Abakumov, Artem M. [Univ. of Antwerp, Antwerp (Belgium); Navrotsky, Alexandra [Univ. of California at Davis, Davis, CA (United States); Kauzlarich, Susan M. [Univ. of California at Davis, Davis, CA (United States)

2014-12-03

We have developed a fast, easy, and scalable synthesis method for Ba<sub>1-xK<sub>x>Fe₂As₂ (0 ≤ x ≤ 1) superconductors using hydrides BaH₂ and KH as a source of barium and potassium metals. Synthesis from hydrides provides better mixing and easier handling of the starting materials, consequently leading to faster reactions and/or lower synthesis temperatures. The reducing atmosphere provided by the evolved hydrogen facilitates preparation of oxygen-free powders. By a combination of methods we have shown that Ba_1-xK<sub>x>Fe₂As₂ obtained via hydride route has the same characteristics as when it is prepared by traditional solid-state synthesis. Refinement from synchrotron powder X-ray diffraction data confirms a linear dependence of unit cell parameters upon K content as well as the tetragonal to orthorhombic transition at low temperatures for compositions with x < 0.2. Magnetic measurements revealed dome-like dependence of superconducting transition temperature T_{c> upon K content with a maximum of 38 K for x close to 0.4. Electron diffraction and high-resolution high-angle annular dark-field scanning transmission electron microscopy indicates an absence of Ba/K ordering, while local inhomogeneity in the Ba/K distribution takes place at a scale of several angstroms along [110] crystallographic direction.}

Electrochemical characterization of V{sub x}Nb{sub y}C{sub z}/Bi{sub x}Ti{sub y}O{sub z} coatings produced through thermo-reactive diffusion and the sputtering technique

Energy Technology Data Exchange (ETDEWEB)

Castro H, S. A.; Alfonso, J. E.; Olaya, J. J., E-mail: jealfonso@unal.edu.co [Universidad Nacional de Colombia, Departamento de Fisica, Grupo de Ciencia de Materiales y Superficies, AA-14490 Bogota (Colombia)

2016-11-01

We present and experimental study of the structural evolution of a bilayer V{sub x}Nb{sub y}C{sub z}/Bi{sub x}Ti{sub y}O{sub z} coating produced via thermo-reactive diffusion (TRD) and the RF sputtering process on D-2 steel substrate. The TRD treatments were carried out in a molten mixture consisting of borax, ferro-niobium, ferro-vanadium, and aluminum, at 1313 K for 3 hours, using a resistance-heating furnace. Bi{sub x}Ti{sub y}O{sub z} coatings were deposited using RF magnetron sputtering on TRD coatings, in order to carry out a study of the corrosion behavior of this compound. The crystallographic structure of the coatings was determined via X-ray diffraction, the corrosion resistance was analyzed through the potentiodynamic polarization test (Tafel Extrapolation) and electrochemical impedance spectroscopic analysis (EIS). X-ray diffraction patterns showed that the ternary coating (VNbC{sub 2}) was preferentially oriented along the [200] direction with a cubic-centered face structure, and the Bi{sub x}Ti{sub y}O{sub z} coatings were amorphous. The electrochemical studies showed that the resistance corrosion of the coatings increased with respect to the bare substrate, and that polarization resistance in the bilayer coatings increased with respect to the ternary coatings, suggesting that the titanate has anti corrosive barrier effects. (Author)

Phase diagrams of novel Tl{sub 4}SnSe{sub 4}–TlSbSe{sub 2}–Tl{sub 2}SnSe{sub 3} quasi-ternary system following DTA and X-ray diffraction

Energy Technology Data Exchange (ETDEWEB)

Barchiy, I.E.; Tatzkar, A.R. [Department of Chemistry, Uzhgorod National University, Pidgirna St., 46, Uzhgorod 88000 (Ukraine); Fedorchuk, A.O. [Department of Inorganic and Organic Chemistry, Lviv National University of Veterinary Medicine and Biotechnologies, Pekarska St., 50, Lviv 79010 (Ukraine); Plucinski, K., E-mail: kpluc2006@wp.pl [Electronics Department, Military University Technology, Warsaw, Kaliskiego 2, Warsaw 00-908 (Poland)

2016-06-25

Phase relation in the Tl{sub 4}SnSe{sub 4}–TlSbSe{sub 2}–Tl{sub 2}SnSe{sub 3} quasiternary system were studied by the DTA and X-ray diffraction in combination with mathematical modeling. The phase diagrams of the Tl{sub 4}SnSe{sub 4}–TlSbSe{sub 2} and Tl{sub 2}SnSe{sub 3}–TlSbSe{sub 2} systems, the perspective views of the phase interaction in the ternary system, the liquidus surface projection, the isothermal section at 423 K were built for the first time. The Tl{sub 4}SnSe{sub 4}–TlSbSe{sub 2}–Tl{sub 2}SnSe{sub 3} system is of the invariant eutectic type and is characterized by the formation of limited solid solutions following initial ternary compounds. New complex compounds are not formed. - Highlights: • Two Tl{sub 4}SnSe{sub 4}–TlSbSe{sub 2},Tl{sub 2}SnSe{sub 3}–TlSbSe{sub 2} systems were explored. • Invariant processes in the ternary system were determined. • New complex compounds were not observed in ternary system.

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

International Nuclear Information System (INIS)

Seminario, Max; Rocca, Jorge J.; Depine, Ricardo A.; Bach, Benny; Bach, Bernie

2001-01-01

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

Structural and microstructural analysis of the U-Gd-O system using X-Ray diffraction data

Energy Technology Data Exchange (ETDEWEB)

Darin, Gaspar; Imakuma, Kengo; Martinez, Luis G.; Turrrilas, Xabier M.; Ichikawa, Rodrigo U.; Silva, André S.B.; Durazzo, Michelangelo; Riella, Humberto G.; Urano, Elita, E-mail: gaspardarin@gmail.com, E-mail: kimakuma@ipen.br, E-mail: lgallego@ipen.br, E-mail: ichikawa@usp.br, E-mail: andre.santos.silva@ipen.br, E-mail: mdurazzo@ipen.br, E-mail: riella@enq.ufsc.br, E-mail: elitaucf@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil). Centro de Combustíveis Nuclear; Institute of Material Science of Barcelona (ICMAB) Barcelona (Spain)

2017-11-01

Gadolinium is one of the best neutron absorber materials and its usage can be considered as a burnable poison for Light Water Reactors (LWR) and as a sacrificial material in Sodium Fast Reactor (SFR). Most of the experiments in the literature focus on nuclear fuel with up to 12 wt% Gd{sub 2}O{sub 3}. Recently, the phase diagram and melting point has been investigated for high contents of Gd{sub 2}O{sub 3} in the U-Gd-O system, that means a solid solution of the composition (U{sub 1-x}, Gd{sub x})O{sub 2} for 0<x<100%. In this work, we present the analysis of the U-Gd-O system for high contents of Gd{sub 2}O{sub 3} using X-ray diffraction data. Rietveld analysis was applied to obtain cell parameters, atomic positions and atomic displacement factors and compared with literature available. Also, the quantification of phases was performed for the different contents of Gd{sub 2}O{sub 3} in the system. Finally, mean crystallite sizes were determined and correlated with the weight fraction of the phases. (author)

Synthesis, characterization and magnetic properties of NiFe{sub 2−x}Ce{sub x}O{sub 4} nanoribbons by electrospinning

Energy Technology Data Exchange (ETDEWEB)

Li, Jianan; Jing, Panpan; Zhang, Xinlei; Cao, Derang; Wei, Jinwu; Pan, Lining [Key Laboratory for Magnetism and Magnetic Materials of the Ministry of Education, Lanzhou University, Lanzhou 730000 (China); Liu, Zhenlin [Analysis and researching center of Gansu province, Lanzhou 730000 (China); Wang, Jianbo [Key Laboratory for Magnetism and Magnetic Materials of the Ministry of Education, Lanzhou University, Lanzhou 730000 (China); Key Laboratory for Special Function Materials and Structural Design of the Ministry of the Education, Lanzhou University, Lanzhou 730000 (China); Liu, Qingfang, E-mail: liuqf@lzu.edu.cn [Key Laboratory for Magnetism and Magnetic Materials of the Ministry of Education, Lanzhou University, Lanzhou 730000 (China)

2017-03-01

NiFe{sub 2−x}Ce{sub x}O{sub 4} (x = 0–0.03) nanoribbons have been successfully fabricated using electrospinning technique and followed by calcining in air at 500 °C. The crystalline, morphologies and compositions of NiFe{sub 2−x}Ce{sub x}O{sub 4} nanoribbons are characterized by X-ray diffraction, selected area electron diffraction, transmission electron microscope, field emission scanning electron microscopy and energy dispersive X-ray spectroscopy (EDX). The results show that the components, mean crystallite sizes and morphologies change along with the content of Ce{sup 3+}. A formation mechanism of NiFe{sub 2-x}Ce{sub x}O{sub 4} nanoribbons is proposed. The magnetic hysteresis loops of NiFe{sub 2−x}Ce{sub x}O{sub 4} nanoribbons reveals that the coercivity changes from 165 Oe to 64 Oe and saturation magnetizations change from 40.97 emu/g to 25.05 emu/g at room temperature. Morevover, the Mössbauer spectra of {sup 57}Fe in NiFe{sub 2−x}Ce{sub x}O{sub 4} nanoribbons is discussed in detail. It is believed that this work will play important role in magnetic application with the advantage of excellent magnetic properties, efficient functionalization and relatively low cost. - Highlights: • The NiFe{sub 2−x}Ce{sub x}O{sub 4} nanoribbons have been fabricated using electrospinning technique. • Ce{sup 3+} ions occupy B sites by replacing Fe{sup 3+} ions. • The coercivity changes from 165 Oe to 64 Oe. • The saturation magnetizations change from 40.97 emu/g to 25.05 emu/g.

Time-resolved X-ray diffraction with accelerator- and laser-plasma-based X-ray sources

Energy Technology Data Exchange (ETDEWEB)

Nicoul, Matthieu

2010-09-01

Femtosecond X-ray pulses are a powerful tool to investigate atomic motions triggered by femtosecond pump pulses. This thesis is dedicated to the production of such pulses and their use in optical pump - X-ray probe measurement. This thesis describes the laser-plasma-based sources available at the University of Duisburg-Essen. Part of it consists of the description of the design, built-up and characterization of a new ''modular'' X-ray source dedicated to optimize the X-ray flux onto the sample under investigation. The acoustic wave generation in femtosecond optically excited semiconductor (gallium arsenide) and metal (gold) was performed using the sources of the University of Duisburg-Essen. The physical answer of the material was modeled by a simple strain model for the semiconductor, pressure model for the metal, in order to gain information on the interplay of the electronic and thermal pressures rising after excitation. Whereas no reliable information could be obtain in gallium arsenide (principally due to the use of a bulk), the model for gold achieved very good agreement, providing useful information. The relaxation time of the electron to lattice energy was found to be (5.0{+-}0.3) ps, and the ratio of the Grueneisen parameters was found to be {gamma}{sub e} / {gamma}{sub i} = (0.5{+-}0.1). This thesis also describes the Sub-Picosecond Pulse Source (SPPS) which existed at the (formally) Stanford Linear Accelerator Center, an accelerator-based X-ray source, and two measurements performed with it. The first one is the detailed investigation of the phonon softening of the A{sub 1g} mode launch in bismuth upon fluence excitation. Detailed information concerning the new equilibrium position and phonon frequency were obtained over extended laser pump fluences. The second measurement concerned the study of the liquid phase dynamics in a newly formed liquid phase following ultrafast melting in indium antimonide. The formation of the liquid phase

High-pressure x-ray diffraction study on lithium borohydride using a synchrotron radiation

Energy Technology Data Exchange (ETDEWEB)

Nakano, S [National Institute for Materials Science, Tsukuba, Ibaraki 305-0044 (Japan); Nakayama, A [Department of Materials Science and Engineering, Meijo University, Nagoya 468-8502 (Japan); Kikegawa, T [Photon Factory (PF), Institute of Materials Structure Science, High Energy Accelerator Research Organization (KEK), Ibaraki 305-0801 (Japan)], E-mail: NAKANO.Satoshi@nims.go.jp

2008-07-15

Lithium borohydride (LiBH{sub 4}) was compressed up to 10 GPa using a diamond-anvil-cell to investigate its high-pressure structure. In-situ x-ray diffraction profiles indicated a pressure-induced transformation at 1.1 GPa, which was consistent with the previous experimental observation such as Raman scattering spectroscopy. The high-pressure phase was indexed on a tetragonal symmetry of P4{sub 2}/mmc, which was not corresponding some structural models proposed by previous calculation studies. An unknown substance (presumably another Li-B-H compound), which was contained in the starting material, also transformed into its high-pressure phase at 0.6 GPa without any relation to the transformation of LiBH{sub 4}.

X-ray filter for x-ray powder diffraction

Science.gov (United States)

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

2018-01-23

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

Mechanical characterisation of surface layers by x-ray diffraction -application to tribology

International Nuclear Information System (INIS)

Farrahi, G.H.

1996-01-01

The results presented in this paper show that X-ray diffraction can be employed for the characterisation of surface layer damage through residual stresses and work hardening by some tribological actions such as fretting and dry sliding. X-ray diffraction technique can also be employed for a rapid and non-destructive measurement of hardness of hardened steel. The diffraction profile analysis can offer a good indication about the materials characteristics and the microstructural evolution caused by heat treatment or by mechanical loading

Controlling a three dimensional electron slab of graded Al{sub x}Ga{sub 1−x}N

Energy Technology Data Exchange (ETDEWEB)

Adhikari, R., E-mail: rajdeep.adhikari@jku.at; Capuzzo, G.; Bonanni, A., E-mail: alberta.bonanni@jku.at [Institut für Halbleiter-und-Festkörperphysik, Johannes Kepler University, Altenbergerstr. 69, A-4040 Linz (Austria); Li, Tian [Institute of Physics, Polish Academy of Sciences, al. Lotników 32/46, PL-02 668 Warszawa (Poland)

2016-01-11

Polarization induced degenerate n-type doping with electron concentrations up to ∼10{sup 20 }cm{sup −3} is achieved in graded Al{sub x}Ga{sub 1−x}N layers (x: 0% → 37%) grown on unintentionally doped and on n-doped GaN:Si buffer/reservoir layers by metal organic vapor phase epitaxy. High resolution x-ray diffraction, transmission electron microscopy, and electron dispersive x-ray spectroscopy confirm the gradient in the composition of the Al{sub x}Ga{sub 1−x}N layers, while Hall effect studies reveal the formation of a three dimensional electron slab, whose conductivity can be adjusted through the GaN(:Si) buffer/reservoir.

Superlattice structure of Ce{sup 3+}-doped BaMgF{sub 4} fluoride crystals - x-ray diffraction, electron spin-resonance, and optical investigations

Energy Technology Data Exchange (ETDEWEB)

Yamaga, M.; Hattori, K. [Department of Electrical and Electronic Engineering, Faculty of Engineering, Gifu University, Gifu (Japan); Kodama, N. [Department of Materials Science and Engineering, Faculty of Engineering and Resource Science, Akita University, Akita (Japan); Ishizawa, N. [Materials and Structures Laboratory, Tokyo Institute of Technology, Yokohama (Japan); Honda, M. [Faculty of Science, Naruto University of Education, Naruto (Japan); Shimamura, K.; Fukuda, T. [Institute for Materials Research, Tohoku University, Sendai (Japan)

2001-09-14

The x-ray diffraction patterns for Ce{sup 3+}-doped BaMgF{sub 4} (BMF) crystals suggest the existence of superlattice structure. The superlattice model is consistent with the characterization of the 4f{sup 1} ground state of Ce{sup 3+} as a probe ion using the electron spin-resonance (ESR) technique. The distinct Ce{sup 3+} luminescence spectra with different peak energies and lifetimes also support the superlattice model. Although the detailed superlattice structure could not be analysed using the diffraction spots, a model has been proposed, taking into account the eight Ce{sup 3+} polyhedra with different anion coordinations in the unit cell of the BMF crystal obtained from the ESR experiments. (author)

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

International Nuclear Information System (INIS)

Andreeva, N. S.

2006-01-01

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

Quantitative determination of phases by X-ray diffraction

International Nuclear Information System (INIS)

Azevedo, A.L.T.

1979-01-01

The internal standard method for the quantitative determination of phases by X-ray diffraction is presented. The method is applicable to multi-phase materials which may be treated as powder. A discussion on sample preparation and some examples follow. (Author) [pt

X-ray diffraction and imaging with a coherent beam: application to X-ray optical elements and to crystals exhibiting phase inhomogeneities

International Nuclear Information System (INIS)

Masiello, F.

2011-05-01

The exceptional properties of synchrotron light sources have been exploited in very different disciplines, from archaeology to chemistry, from material science to biology, from medicine to physics. Among these properties it is important to mention the high brilliance, continuum spectrum, high degree of polarization, time structure, small source size and divergence of the beam, the last resulting in a high transversal coherence of the produced radiation. This high transversal coherence of the synchrotron sources has permitted the development of new techniques, e.g. phase contrast imaging, X-ray photon correlation spectroscopy and coherent X-ray diffraction imaging (CXDI). This thesis work will consist essentially of three parts. In the first part it will be presented the work done as a member of the X-ray Optics Group of ESRF in the characterization of high quality diamond crystals foreseen as X-ray optical elements. The characterization has been done using different complementary X-ray techniques, such as high resolution diffraction, topography, grazing incidence diffraction, reflectivity and measurements of the coherence preservation using the Talbot effect. In the second part, I will show the result obtained in the study of the temperature behaviours of the domain in periodically poled ferroelectrics crystals. This type of measurements, based on Bragg-Fresnel diffraction, are possible only thanks to the high degree of coherence of the beam. In the third part, I will present the results obtained in the characterization of diamonds foreseen for applications other than X-ray optical elements. (author)

Direct methods for surface X-ray diffraction

International Nuclear Information System (INIS)

Saldin, D. K.; Harder, R.; Shneerson, V. L.; Vogler, H.; Moritz, W.

2000-01-01

We develop of a direct method for surface X-ray diffraction that exploits the holographic feature of a known reference wave from the substrate. A Bayesian analysis of the optimal inference to be made from an incomplete data set suggests a maximum entropy algorithm that balances agreement with the data and other statistical considerations

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

Energy Technology Data Exchange (ETDEWEB)

Tsusaka, Y., E-mail: tsusaka@sci.u-hyogo.ac.jp; Takano, H. [Graduate School of Material Science, University of Hyogo, 3-2-1, Kouto, Kamigori, Hyogo 678-1297 (Japan); Takeda, S. [SPring-8 Service Co., Ltd., 1-20-5, Kouto, Shingu, Tatsuno, Hyogo 679-5165 (Japan); Yokoyama, K.; Matsui, J. [Synchrotron Radiation Nanotechnology Center, University of Hyogo, 1-490-2, Kouto, Shingu, Tatsuno, Hyogo 679-5165 (Japan); Kagoshima, Y. [Graduate School of Material Science, University of Hyogo, 3-2-1, Kouto, Kamigori, Hyogo 678-1297 (Japan); Synchrotron Radiation Nanotechnology Center, University of Hyogo, 1-490-2, Kouto, Shingu, Tatsuno, Hyogo 679-5165 (Japan)

2016-02-15

X-ray topographs are taken for a sapphire wafer with the [0001] surface normal, as an example, by forward transmitted synchrotron x-ray beams combined with two-dimensional electronic arrays in the x-ray detector having a spatial resolution of 1 μm. They exhibit no shape deformation and no position shift of the dislocation lines on the topographs. Since the topography is performed under multiple-beam diffraction conditions, the topographic images of a single diffraction (two-wave approximation condition) or plural diffractions (six-wave approximation condition) can be recorded without large specimen position changes. As usual Lang topographs, it is possible to determine the Burgers vector of each dislocation line. Because of high parallelism of the incoming x-rays and linear sensitivity of the electronic arrays to the incident x-rays, the present technique can be used to visualize individual dislocations in single crystals of the dislocation density as high as 1 × 10{sup 5} cm{sup −2}.

Enhancement of magnetoresistance and ferromagnetic coupling in the complex perovskites CaCu{sub 3}(Mn{sub 4−x}Al{sub x})O{sub 12} (x = 0, 0.2, 0.4, and 0.6): A neutron diffraction study

Energy Technology Data Exchange (ETDEWEB)

Ben Hassine, R.; Cherif, W. [Faculty of Sciences, Sfax University, Sfax, B.P. 1171-3000 (Tunisia); Sánchez-Benítez, J. [Departamento de Química Física I, Facultad de Ciencias Químicas, Universidad Complutense de Madrid, E-28040 Madrid (Spain); Mompean, F. J.; Alonso, J. A., E-mail: ja.alonso@icmm.csic.es [Instituto de Ciencia de Materiales de Madrid, Consejo Superior de Investigaciones Científicas, Cantoblanco, E-28049 Madrid (Spain); Fernández-Díaz, M. T. [Institut Laue-Langevin, B.P. 156, F-38042 Grenoble Cedex 9 (France); Elhalouani, F. [National School of Engineers, Sfax University, Sfax, B.P. W 3038 (Tunisia)

2015-09-14

New compounds of the series CaCu{sub 3}(Mn{sub 4−x}Al{sub x})O{sub 12} have been prepared under high pressure conditions (2 GPa), in the presence of KClO{sub 4} as oxidizing agent to stabilize Mn{sup 3+,4+} mixed valence. The polycrystalline samples have been characterized by x-ray diffraction, neutron powder diffraction (NPD), magnetic, and magnetotransport measurements. All the samples are cubic, space group Im-3. These oxides adopt a superstructure of ABO{sub 3} perovskite given by the long-range 1:3 ordering of Ca{sup 2+} and Cu{sup 2+} ions at the A sublattice. The NPD study for x = 0.4 shows that Al{sup 3+} ions are statistically distributed at the octahedral positions, being the (Mn,Al)O{sub 6} octahedra strongly tilted, with superexchange (Mn,Al)-O-(Mn,Al) angles of 142.1°. Also, neutron data clearly show that some Mn{sup 3+} ions (0.65(2) per formula) are located together with Cu{sup 2+} at the square-planar 6b positions. Regarding the magnetic properties, all the compounds present a spontaneous increase of the magnetization below T{sub C}, typical of ferro-or ferrimagnetic materials, with T{sub C} decreasing upon Al introduction. The magnetic structure determined from low-temperature NPD data unveils a ferromagnetic coupling between (Cu{sup 2+}, Mn{sup 3+}){sub 6b} spins and Mn{sub 8c} spins at octahedral positions; this is in contrast with the ferrimagnetic structure observed for RCu{sub 3}Mn{sub 4}O{sub 12} and CaCu{sub 3}Mn{sub 4}O{sub 12}, where an AFM coupling is observed between both magnetic sublattices. Interestingly, an enhancement of the magnetoresistance effect is observed for x = 0.2, well beyond that found for the parent compound. This effect, in materials subtly doped with non-magnetic elements at the Mn positions, may be of interest for applications.

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

Energy Technology Data Exchange (ETDEWEB)

Ichiyanagi, Kouhei; Sasaki, Yuji C. [Department of Advanced Materials Science, Graduate School of Frontier Sciences, The University of Tokyo, 609 Kiban Building 5-1-5 Kashiwanoha, Kahiwashi, Chiba 277-8561 (Japan); Japan Science and Technology Agency, CREST, CREST, Sasaki-Team, 609 Kiban Building, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8561 (Japan); Sekiguchi, Hiroshi; Hoshino, Masato; Kajiwara, Kentaro; Senba, Yasunori; Ohashi, Haruhiko; Ohta, Noboru [Japan Synchrotron Radiation Research Institute, SPring-8, 1-1-1 Kouto, Sayo, Hyogo 679-5198 (Japan); Hoshisashi, Kentaro; Jae-won, Chang; Tokue, Maki; Matsushita, Yufuku [Department of Advanced Materials Science, Graduate School of Frontier Sciences, The University of Tokyo, 609 Kiban Building 5-1-5 Kashiwanoha, Kahiwashi, Chiba 277-8561 (Japan); Nishijima, Masaki; Inoue, Yoshihisa [Department of Applied Chemistry and Office for University-Industry Collaboration, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871 (Japan); Yagi, Naoto [Japan Science and Technology Agency, CREST, CREST, Sasaki-Team, 609 Kiban Building, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8561 (Japan); Japan Synchrotron Radiation Research Institute, SPring-8, 1-1-1 Kouto, Sayo, Hyogo 679-5198 (Japan)

2013-10-15

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

X-ray diffraction characteristics of curved monochromators for sychrotron radiation

International Nuclear Information System (INIS)

Boeuf, A.; Rustichelli, F.; Mazkedian, S.; Puliti, P.; Melone, S.

1978-01-01

A theoretical study is presented concerning the diffraction characteristics of curved monochromators for X-ray synchrotron radiation used at the laboratories of Hamburg, Orsay and Stanford. The investigation was performed by extending to the X-ray case a simple model recently developed and fruitfully employed to describe the neutron diffraction properties of curved monochromators. Several diffraction patterns were obtained corresponding to different monochromator materials (Ge, Si) used by the different laboratories, for different reflecting planes (111), (220), asymmetry angles, X-ray wave-lengths (Mo Kα, Cu Kα, Cr Kα) and curvature radii. The results are discussed in physical terms and their implications on the design of curved monochromators for synchrotron radiation are presented. In particular, the study shows that all the monochromators used in the different laboratories should behave practically as perfect crystals and therefore should have a very low integrated reflectivity corresponding to an optimized wavelength passband Δlambda/lambda approximately 10 -4 . The gain that can be obtained by increasing the curvature, by introducing a gradient in the lattice spacing or by any other kind of imperfection is quite limited and much lower than the desirable value. The adopted model can help in obtaining a possible moderate gain in intensity by also taking into consideration other parameters, such as crystal material, reflecting plane, asymmetry of the reflection and X-ray wavelength. (Auth.)

Diffractive-refractive optics: (+,-,-,+) X-ray crystal monochromator with harmonics separation

Czech Academy of Sciences Publication Activity Database

Hrdý, Jaromír; Mikulík, P.; Oberta, Peter

2011-01-01

Roč. 18, č. 2 (2011), s. 299-301 ISSN 0909-0495 R&D Projects: GA MPO FR-TI1/412 Institutional research plan: CEZ:AV0Z10100522 Keywords : diffractive-refractive optics * x-ray synchrotron radiation monochromator * x-ray crystal monochromator * harmonics separation Subject RIV: BH - Optics, Masers, Lasers Impact factor: 2.726, year: 2011

X-ray diffraction topography. Stages and tendencies of development

International Nuclear Information System (INIS)

Shul'pina, I.L.

2000-01-01

The physical foundation of X-ray diffraction topography, its methods, the achievements in image theory, the stages of evolution were described in this review. It was found that modern topography is well along in development associated with the use of third-generation synchrotron radiation and with its adaptation to advance materials and problems of materials science. Some proposals about prospects for X-ray topography progress in the future have been made [ru

Advances in thin film diffraction instrumentation by X-ray optics

International Nuclear Information System (INIS)

Haase, A.

1996-01-01

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

Advances in thin film diffraction instrumentation by X-ray optics

Energy Technology Data Exchange (ETDEWEB)

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

1996-09-01

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

Thermal stability of amorphous structure and magnetic properties Fe{sub 80-x}Co{sub x}P{sub 14}B {sub 6} (x=20-40) ribbons

Energy Technology Data Exchange (ETDEWEB)

Kostyrya, S.A.; Idzikowski, B. [Institute of Molecular Physics, Polish Academy of Sciences, M. Smoluchowskiego 17, 60-179 Poznan (Poland); Tkatch, V.I.; Popov, V.V.; Rassolov, S.G. [Donetsk Physics and Engineering Institute of National Academy of Sciences of Ukraine, R. Luxemburg 72, 83114 Donetsk (Ukraine)

2006-01-01

Amorphous structure and its thermal stability as well as magnetic properties of Fe{sub 80-x}Co{sub x}P{sub 14}B{sub 6} (20{<=}x{<=}40) glasses have been studied by X-ray diffraction, non-isothermal differential scanning calorimetry (DSC) and thermomagnetic (TMG) measurements. The Curie temperature increases with Co content, while the glass transition and crystallization onset temperatures decrease. As a result, for alloys x=30, 32 and 35 at%, the transition into paramagnetic state take place close to glass transition temperature. However, for x=40 at% the TMG curve, in the vicinity of magnetic transition temperature, is overlapped by ferromagnetic crystallization products. (copyright 2006 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

Single-particle coherent diffractive imaging with a soft x-ray free electron laser: towards soot aerosol morphology

Science.gov (United States)

Bogan, Michael J.; Starodub, Dmitri; Hampton, Christina Y.; Sierra, Raymond G.

2010-10-01

The first of its kind, the Free electron LASer facility in Hamburg, FLASH, produces soft x-ray pulses with unprecedented properties (10 fs, 6.8-47 nm, 1012 photons per pulse, 20 µm diameter). One of the seminal FLASH experiments is single-pulse coherent x-ray diffractive imaging (CXDI). CXDI utilizes the ultrafast and ultrabright pulses to overcome resolution limitations in x-ray microscopy imposed by x-ray-induced damage to the sample by 'diffracting before destroying' the sample on sub-picosecond timescales. For many lensless imaging algorithms used for CXDI it is convenient when the data satisfy an oversampling constraint that requires the sample to be an isolated object, i.e. an individual 'free-standing' portion of disordered matter delivered to the centre of the x-ray focus. By definition, this type of matter is an aerosol. This paper will describe the role of aerosol science methodologies used for the validation of the 'diffract before destroy' hypothesis and the execution of the first single-particle CXDI experiments being developed for biological imaging. FLASH CXDI now enables the highest resolution imaging of single micron-sized or smaller airborne particulate matter to date while preserving the native substrate-free state of the aerosol. Electron microscopy offers higher resolution for single-particle analysis but the aerosol must be captured on a substrate, potentially modifying the particle morphology. Thus, FLASH is poised to contribute significant advancements in our knowledge of aerosol morphology and dynamics. As an example, we simulate CXDI of combustion particle (soot) morphology and introduce the concept of extracting radius of gyration of fractal aggregates from single-pulse x-ray diffraction data. Future upgrades to FLASH will enable higher spatially and temporally resolved single-particle aerosol dynamics studies, filling a critical technological need in aerosol science and nanotechnology. Many of the methodologies described for FLASH will

Single-particle coherent diffractive imaging with a soft x-ray free electron laser: towards soot aerosol morphology

International Nuclear Information System (INIS)

Bogan, Michael J; Starodub, Dmitri; Hampton, Christina Y; Sierra, Raymond G

2010-01-01

The first of its kind, the Free electron LASer facility in Hamburg, FLASH, produces soft x-ray pulses with unprecedented properties (10 fs, 6.8-47 nm, 10 12 photons per pulse, 20 μm diameter). One of the seminal FLASH experiments is single-pulse coherent x-ray diffractive imaging (CXDI). CXDI utilizes the ultrafast and ultrabright pulses to overcome resolution limitations in x-ray microscopy imposed by x-ray-induced damage to the sample by 'diffracting before destroying' the sample on sub-picosecond timescales. For many lensless imaging algorithms used for CXDI it is convenient when the data satisfy an oversampling constraint that requires the sample to be an isolated object, i.e. an individual 'free-standing' portion of disordered matter delivered to the centre of the x-ray focus. By definition, this type of matter is an aerosol. This paper will describe the role of aerosol science methodologies used for the validation of the 'diffract before destroy' hypothesis and the execution of the first single-particle CXDI experiments being developed for biological imaging. FLASH CXDI now enables the highest resolution imaging of single micron-sized or smaller airborne particulate matter to date while preserving the native substrate-free state of the aerosol. Electron microscopy offers higher resolution for single-particle analysis but the aerosol must be captured on a substrate, potentially modifying the particle morphology. Thus, FLASH is poised to contribute significant advancements in our knowledge of aerosol morphology and dynamics. As an example, we simulate CXDI of combustion particle (soot) morphology and introduce the concept of extracting radius of gyration of fractal aggregates from single-pulse x-ray diffraction data. Future upgrades to FLASH will enable higher spatially and temporally resolved single-particle aerosol dynamics studies, filling a critical technological need in aerosol science and nanotechnology. Many of the methodologies described for FLASH will

Epitaxial Al{sub x}Ga{sub 1–x}As:Mg alloys with different conductivity types

Energy Technology Data Exchange (ETDEWEB)

Seredin, P. V., E-mail: paul@phys.vsu.ru; Lenshin, A. S. [Voronezh State University (Russian Federation); Arsentiev, I. N., E-mail: arsentyev@mail.ioffe.ru; Zhabotinskii, A. V.; Nikolaev, D. N.; Tarasov, I. S.; Shamakhov, V. V. [Russian Academy of Sciences, Ioffe Physical–Technical Institute (Russian Federation); Prutskij, Tatiana, E-mail: prutskiy@yahoo.com [Benemérita Universidad Autónoma de Puebla, Instituto de Ciencias (Mexico); Leiste, Harald; Rinke, Monika [Karlsruhe Nano Micro Facility (Germany)

2017-01-15

The structural, optical, and energy properties of epitaxial Al{sub x}Ga{sub 1–x}As:Mg/GaAs(100) heterostructures at different levels of doping with Mg are studied by high-resolution X-ray diffraction analysis and Raman and photoluminescence spectroscopies. It is shown that, by choosing the technological conditions of Al{sub x}Ga{sub 1–x}As:Mg alloy production, it is possible to achieve not only different conductivity types, but also substantially different charge-carrier concentrations in an epitaxial film.

Random spin configurations of Co cations in LaCo{sub 1-x}Mg{sub x}O{sub 3} (0 < x {<=} 0.20) perovskite oxides: Magnetic and transport properties

Energy Technology Data Exchange (ETDEWEB)

Lopez, M.L., E-mail: marisal@quim.ucm.es [Departamento de Quimica Inorganica I, Facultad de Ciencias Quimicas, Universidad Complutense, Ciudad Universitaria s/n, 28040 Madrid (Spain); Arillo, M.A.; Alvarez-Serrano, I.; Martin, P.; Rodriguez, E.; Pico, C.; Veiga, M.L. [Departamento de Quimica Inorganica I, Facultad de Ciencias Quimicas, Universidad Complutense, Ciudad Universitaria s/n, 28040 Madrid (Spain)

2010-04-15

Perovskite-type cobaltites LaCo{sub 1-x}Mg{sub x}O{sub 3} (0 < x {<=} 0.20) were synthesised by the liquid mix technique and structurally characterised by X-ray diffraction and neutron powder diffraction. This system can be regarded as LaCoO{sub 3}-derived by means of partial substitution of trivalent cobalt ions by Mg{sup 2+}. This doping is accompanied by the stabilization of the correspondent amount of Co{sup 4+} cations as it has been established from ICP, thermogravimetric and neutron diffraction results. The title materials behave as semiconductors up to 800 K. Above this temperature they show a transition to the metallic state. Magnetic susceptibility and magnetization measurements show weak ferromagnetic interactions at 5 K which has been interpreted taking into account disordered spin configurations for the cobalt cations.

Extinction correction in white X-ray and neutron diffraction

International Nuclear Information System (INIS)

Tomiyoshi, S.; Yamada, M.; Watanabe, H.

1980-01-01

Extinction effects in white-beam X-ray and neutron diffraction are considered. In white-beam diffraction, a small deviation of the wavelength from the Bragg condition Δlambda is a variable which represents the line profile of the diffraction peaks, so that by using the new parameter Δlambda the theory is converted to one in white-beam diffraction. It is shown that for a convex crystal, primary extinction agrees with the results calculated already for monochromatic diffraction. The same relation is shown to hold in secondary extinction. It is concluded that extinction theory derived for monochromatic diffraction is applicable without any modification in white-beam diffraction. (Auth.)

Femtosecond X-ray diffraction from an aerosolized beam of protein nanocrystals.

Science.gov (United States)

Awel, Salah; Kirian, Richard A; Wiedorn, Max O; Beyerlein, Kenneth R; Roth, Nils; Horke, Daniel A; Oberthür, Dominik; Knoska, Juraj; Mariani, Valerio; Morgan, Andrew; Adriano, Luigi; Tolstikova, Alexandra; Xavier, P Lourdu; Yefanov, Oleksandr; Aquila, Andrew; Barty, Anton; Roy-Chowdhury, Shatabdi; Hunter, Mark S; James, Daniel; Robinson, Joseph S; Weierstall, Uwe; Rode, Andrei V; Bajt, Saša; Küpper, Jochen; Chapman, Henry N

2018-02-01

High-resolution Bragg diffraction from aerosolized single granulovirus nanocrystals using an X-ray free-electron laser is demonstrated. The outer dimensions of the in-vacuum aerosol injector components are identical to conventional liquid-microjet nozzles used in serial diffraction experiments, which allows the injector to be utilized with standard mountings. As compared with liquid-jet injection, the X-ray scattering background is reduced by several orders of magnitude by the use of helium carrier gas rather than liquid. Such reduction is required for diffraction measurements of small macromolecular nanocrystals and single particles. High particle speeds are achieved, making the approach suitable for use at upcoming high-repetition-rate facilities.

X-ray diffraction investigation of the sulphur induced 4x1 reconstruction of Ni(110)

DEFF Research Database (Denmark)

Foss, M.; Feidenhans'l, R.; Nielsen, M.

1993-01-01

The atomic structure of the Ni(110)4 x 1-S reconstruction has been determined on the basis of surface X-ray diffraction measurements. An analysis of the in-plane diffraction data shows that the model consists of Ni rows along the [001] direction, two for every 4 x 1 unit cell, corresponding to 0....

Control of synchrotron x-ray diffraction by means of standing acoustic waves

International Nuclear Information System (INIS)

Zolotoyabko, E.; Quintana, J.P.

2004-01-01

Synchrotron x-ray diffraction measurements in quartz crystals of different thickness excited by standing acoustic waves were carried out at the Advanced Photon Source of Argonne National Laboratory. We demonstrated the ability to significantly modify the quartz rocking curves for 20-25 keV x rays by changing the shear wave parameters in the frequency range between 15 and 105 MHz. Dynamic deformation introduced into the crystal lattice by acoustic waves resulted in a remarkable broadening of the rocking curves. The broadening effect strongly depends on the strength of the ultrasound, which can be easily regulated by changing the acoustic amplitude or frequency near the resonance. The maximum rocking curve broadening reached 17 times, which corresponds to the wavelength band, Δλ/λ=4x10 -3 , when used as a monochromator or analyzer for 20-25 keV x rays. The initial rocking curve shape is restored by sweeping the acoustic frequency within a 50-100 kHz range near the resonance. The tunable broadening effect allows effective manipulation of x-ray intensities in time domain. Time-resolved x-ray diffraction measurements under a 19.6 MHz acoustic wave excitation were performed by synchronizing the acoustic wave and x-ray burst periodicity. We used the fact that twice per period the standing wave produces a zero net deformation across the crystal thickness. By introducing an oscillating delay to the acoustic excitation, we were able to effectively change the phase of the acoustic wave relative to the x-ray burst periodicity. The x-ray diffraction intensity was strongly affected by tuning the timing of the x-ray arrivals to the minimum or maximum acoustic deformation. A deep modulation of x rays was observed in a wide frequency range between 0.1 Hz and 1 MHz, which certifies that acoustically excited quartz crystals can potentially be used as slow and fast x-ray modulators with high duty cycle

Piezoelectric and ferroelectric properties of lead-free (1-x)(Na{sub 1−y}K{sub y})(Nb{sub 1−z}Sb{sub z})O{sub 3}-xBaTiO{sub 3} solid solution

Energy Technology Data Exchange (ETDEWEB)

Sasikumar, S., E-mail: sasikuhan@gmail.com [Research Centre and Post Graduate Department of Physics, The Madura College, Madurai 625 011, Tamil Nadu (India); Saravanan, R. [Research Centre and Post Graduate Department of Physics, The Madura College, Madurai 625 011, Tamil Nadu (India); Aravinth, K. [SSN Research Center, SSN College of Engineering, Kalavakkam 603 110, Tamil Nadu (India)

2017-05-01

The solid solutions of lead-free (1-x)(Na{sub 1-y}K{sub y})(Nb{sub 1-z}Sb{sub z})O{sub 3}-xBaTiO{sub 3} (with x=0.1, 0.2; y=0.03, 0.05; z=0.05, 0.1) (abbreviated as (1-x)NKNS-xBT) ceramics have been synthesized using conventional solid-state reaction method. The results of X-ray diffraction analysis show that all the grown specimens of NKNS display typical perovskite structure. With BaTiO{sub 3} (BT) addition, a structural phase transition from tetragonal to cubic structure has been observed. The structural parameters of (1-x)NKNS-xBT powders were determined by profile refinements based on the analysis of X-ray powder diffraction. The charge density distributions of the prepared samples have been investigated by observed structure factors to understand the chemical bonding nature of (1-x)NKNS-xBT powders. The optical absorption of the ceramics has been investigated using UV–visible spectrophotometer. Scanning electron microscopic (SEM) measurements were performed to study the surface morphology of the prepared solid solutions. The elemental compositions of the (1-x)NKNS-xBT samples were analyzed by energy-dispersive X-ray (EDS) spectrometer. The dielectric constant versus temperature plots of the solid solutions exhibit ferroelectric to paraelectric phase transition, which is dependent on the BaTiO{sub 3} content. The ferroelectric nature of the samples has been determined through polarization and electric field hysteresis measurements.

High-pressure phase transition in silicon carbide under shock loading using ultrafast x-ray diffraction

Science.gov (United States)

Tracy, S. J.; Smith, R. F.; Wicks, J. K.; Fratanduono, D. E.; Gleason, A. E.; Bolme, C.; Speziale, S.; Appel, K.; Prakapenka, V. B.; Fernandez Panella, A.; Lee, H. J.; MacKinnon, A.; Eggert, J.; Duffy, T. S.

2017-12-01

The behavior of silicon carbide (SiC) under shock loading was investigated through a series of time-resolved pump-probe x-ray diffraction (XRD) measurements. SiC is found at impact sites and has been put forward as a possible constituent in the proposed class of extra-solar planets known as carbon planets. Previous studies have used wave profile measurements to identify a phase transition under shock loading near 1 Mbar, but crystal structure information was not obtained. We have carried out an in situ XRD study of shock-compressed SiC using the Matter in Extreme Conditions instrument of the Linac Coherent Light Source. The femtosecond time resolution of the x-ray free electron laser allows for the determination of time-dependent atomic arrangements during shock loading and release. Two high-powered lasers were used to generate ablation-driven compression waves in the samples. Time scans were performed using the same drive conditions and nominally identical targets. For each shot in a scan, XRD data was collected at a different probe time after the shock had entered the SiC. Probe times extended up to 40 ns after release. Scans were carried out for peak pressures of 120 and 185 GPa. Our results demonstrate that SiC transforms directly from the ambient tetrahedrally-coordinated phase to the octahedral B1 structure on the nanosecond timescale of laser-drive experiments and reverts to the tetrahedrally coordinated ambient phase within nanoseconds of release. The data collected at 120 GPa exhibit diffraction peaks from both compressed ambient phase and transformed B1 phase, while the data at 185 GPa show a complete transformation to the B1 phase. Densities determined from XRD peaks are in agreement with an extrapolation of previous continuum data as well as theoretical predictions. Additionally, a high degree of texture was retained in both the high-pressure phase as well as on back transformation. Two-dimensional fits to the XRD data reveal details of the

X-Ray diffraction Investigation of Electrochemically Deposited Copper

DEFF Research Database (Denmark)

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

2004-01-01

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

Size effect in X-ray and electron diffraction patterns from hydroxyapatite particles

International Nuclear Information System (INIS)

Suvorova, E.I.; Buffat, P.-A.

2001-01-01

High-resolution transmission electron microscopy (HRTEM), electron microdiffraction, and X-ray diffraction were used to study hydroxyapatite specimens with particle sizes from a few nanometers to several hundreds of nanometers. Diffuse scattering (without clear reflections in transmission diffraction patterns) or strongly broadened peaks in X-ray diffraction patterns are characteristic for agglomerated hydroxyapatite nanocrystals. However, HRTEM and microdiffraction showed that this cannot be considered as an indication of the amorphous state of the matter but rather as the demonstration of size effect and the morphological and structural features of hydroxyapatite nanocrystals

Electron-density distribution in cubic SrTiO{sub 3}: a comparative {gamma}-ray diffraction study

Energy Technology Data Exchange (ETDEWEB)

Jauch, W. [Hahn-Meitner-Inst., Berlin (Germany); Reehuis, M. [Max-Planck-Institut fuer Festkoerperforschung, Stuttgart (Germany)

2005-07-01

The electron density and atomic displacements in the perovskite SrTiO{sub 3} have been studied using extensive and accurate {gamma}-ray diffraction data ({lambda}=0.0392 Aa) at room temperature. The six strongest low-order structure factors have been determined under extinction-free conditions. Gram-Charlier series expansion of the thermal parameters have revealed no evidence for anharmonicity. The population of the 3d subshell on Ti is found to be close to zero, in agreement with the observed magnetic behaviour. The electronic properties at the bond critical points indicate ionic Ti-O and Sr-O interactions of different strengths, which is corroborated by the net charges of the atomic basins [q(Sr)=1.18 vertical stroke e vertical stroke, q(Ti)=3.10 vertical stroke e vertical stroke, q(O)=1.42 vertical stroke e vertical stroke ]. A critical comparison is made with earlier experimental results from laboratory X-ray, synchrotron X-ray, electron and neutron diffraction studies. Agreement and discrepancies are identified and resolved. (orig.)

Sequential x-ray diffraction topography at 1-BM x-ray optics testing beamline at the advanced photon source

Energy Technology Data Exchange (ETDEWEB)

Stoupin, Stanislav, E-mail: sstoupin@aps.anl.gov; Shvyd’ko, Yuri; Trakhtenberg, Emil; Liu, Zunping; Lang, Keenan; Huang, Xianrong; Wieczorek, Michael; Kasman, Elina; Hammonds, John; Macrander, Albert; Assoufid, Lahsen [Advanced Photon Source, Argonne National Laboratory, Argonne, IL 60439 (United States)

2016-07-27

We report progress on implementation and commissioning of sequential X-ray diffraction topography at 1-BM Optics Testing Beamline of the Advanced Photon Source to accommodate growing needs of strain characterization in diffractive crystal optics and other semiconductor single crystals. The setup enables evaluation of strain in single crystals in the nearly-nondispersive double-crystal geometry. Si asymmetric collimator crystals of different crystallographic orientations were designed, fabricated and characterized using in-house capabilities. Imaging the exit beam using digital area detectors permits rapid sequential acquisition of X-ray topographs at different angular positions on the rocking curve of a crystal under investigation. Results on sensitivity and spatial resolution are reported based on experiments with high-quality Si and diamond crystals. The new setup complements laboratory-based X-ray topography capabilities of the Optics group at the Advanced Photon Source.

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

International Nuclear Information System (INIS)

Souza, A.M. de; Carmo, L.C.S. do; Pereira, V.J.E.; Soares, E.A.

1984-01-01

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

Synthesis and magnetic properties of ferrites spinels Mg{sub x}Cu{sub 1-x}Fe{sub 2}O{sub 4}

Energy Technology Data Exchange (ETDEWEB)

Mounkachi, O.; Hamedoun, M. [Institute of Nanomaterials and Nanotechnology, MAScIR, Rabat (Morocco); Belaiche, M. [Institute of Nanomaterials and Nanotechnology, MAScIR, Rabat (Morocco); Hassan II Academy of Science and Technology, Rabat (Morocco); Laboratoire de Magnetisme, Materiaux Magnetiques, Microonde et Ceramique, Ecole Normale Superieure, Universite Mohammed V-Agdal, B.P. 9235, Ocean, Rabat (Morocco); Benyoussef, A. [Institute of Nanomaterials and Nanotechnology, MAScIR, Rabat (Morocco); Hassan II Academy of Science and Technology, Rabat (Morocco); LMPHE, (URAC 12), Faculte des Sciences, Universite Mohammed V-Agdal, Rabat (Morocco); Masrour, R. [Laboratory of Materials, Process, Environment and Quality, Cady Ayad University, National School of Applied Sciences, Safi (Morocco); El Moussaoui, H. [Institute of Nanomaterials and Nanotechnology, MAScIR, Rabat (Morocco); LMPHE, (URAC 12), Faculte des Sciences, Universite Mohammed V-Agdal, Rabat (Morocco); Sajieddine, M., E-mail: hamedoun@hotmail.com [Faculte des Sciences et Techniques, Universite Moulay Slimane, Beni Mellal (Morocco)

2012-01-01

Polycrystalline Mg{sub 0.6}Cu{sub 0.4}Fe{sub 2}O{sub 4} ferrites have been prepared using solid-state reaction technique. Their structural and magnetic properties have been studied, using X-ray diffraction and magnetic measurements. Using mean field theory and high-temperature series expansions (HTSE), extrapolated with the pade approximants method, the magnetic properties of Mg{sub 1-x}Cu{sub x}Fe{sub 2}O{sub 4} have been studied. The nearest neighbor super-exchange interactions for intra-site and inter-site of the Mg{sub 1-x}Cu{sub x}Fe{sub 2}O{sub 4} ferrites spinels, in the range 0{<=}x{<=}1, have been computed using the probability approach, based on Moessbauer data. The Curie temperature T{sub c} is calculated as a function of Mg concentration. The obtained theoretical results are in good agreement with experimental ones obtained by magnetic measurements.

On the evaluation of X-ray diffraction experiments by the regularization method

Energy Technology Data Exchange (ETDEWEB)

Trubin, V.A.; Szasz, A. (Lab. of Surface and Interface Physics, Eoetvoes Univ., Budapest (Hungary))

1991-05-16

The characteristic property of diffractometers as the presence of occasional and systematic errors in measured patterns requires such an evaluation which is as informative as possible. This circumstance gives rise to the problem of optimal planning of the experiment. The X-ray diffraction optimization problem with application of the regularization method is studied. The proposal permits to determine more accurately the unknown true characteristics of the X-ray diffraction experiment. (orig.).

On the evaluation of X-ray diffraction experiments by the regularization method

International Nuclear Information System (INIS)

Trubin, V.A.; Szasz, A.

1991-01-01

The characteristic property of diffractometers as the presence of occasional and systematic errors in measured patterns requires such an evaluation which is as informative as possible. This circumstance gives rise to the problem of optimal planning of the experiment. The X-ray diffraction optimization problem with application of the regularization method is studied. The proposal permits to determine more accurately the unknown true characteristics of the X-ray diffraction experiment. (orig.)

Direct observation of ultrafast atomic motion using time-resolved X-ray diffraction

Energy Technology Data Exchange (ETDEWEB)

Shymanovich, U.

2007-11-13

This thesis is dedicated to the study of the atomic motion in laser irradiated solids on a picosecond to subpicosecond time-scale using the time-resolved X-ray diffraction technique. In the second chapter, the laser system, the laser-plasma based X-ray source and the experimental setup for optical pump / X-ray probe measurements were presented. Chapter 3 is devoted to the characterization and comparison of different types of X-ray optics. Chapter 4 presented the time-resolved X-ray diffraction experiments performed for this thesis. The first two sections of this chapter discuss the measurements of initially unexpected strain-induced transient changes of the integrated reflectivity of the X-ray probe beam. The elimination of the strain-induced transient changes of the integrated reflectivity represented an important prerequisite to perform the study of lattice heating in Germanium after femtosecond optical excitation by measuring the transient Debye-Waller effect. The third section describes the investigations of acoustic waves upon ultrafast optical excitation and discusses the two different pressure contributions driving them: the thermal and the electronic ones. (orig.)

Direct observation of ultrafast atomic motion using time-resolved X-ray diffraction

International Nuclear Information System (INIS)

Shymanovich, U.

2007-01-01

This thesis is dedicated to the study of the atomic motion in laser irradiated solids on a picosecond to subpicosecond time-scale using the time-resolved X-ray diffraction technique. In the second chapter, the laser system, the laser-plasma based X-ray source and the experimental setup for optical pump / X-ray probe measurements were presented. Chapter 3 is devoted to the characterization and comparison of different types of X-ray optics. Chapter 4 presented the time-resolved X-ray diffraction experiments performed for this thesis. The first two sections of this chapter discuss the measurements of initially unexpected strain-induced transient changes of the integrated reflectivity of the X-ray probe beam. The elimination of the strain-induced transient changes of the integrated reflectivity represented an important prerequisite to perform the study of lattice heating in Germanium after femtosecond optical excitation by measuring the transient Debye-Waller effect. The third section describes the investigations of acoustic waves upon ultrafast optical excitation and discusses the two different pressure contributions driving them: the thermal and the electronic ones. (orig.)

Structural phase transition in lanthanum gallate as studied by Raman and X-ray diffraction measurements

Energy Technology Data Exchange (ETDEWEB)

Dhak, P.; Pramanik, P. [Department of Chemistry, Indian Institute of Technology, Kharagpur 721302 (India); Bhattacharya, S.; Roy, Anushree [Department of Physics, Indian Institute of Technology, Kharagpur 721302 (India); Achary, S.N.; Tyagi, A.K. [Chemistry Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India)

2011-08-15

Lanthanum gallate (LaGaO{sub 3}) is known to undergo orthorhombic to rhombohedral first order phase transition at 150 C. In this article we have shown that by introducing 2% La deficiency in the system, coexistence of above two phases can be obtained at lower temperature and a complete phase transition occurs at 200 C. The evolution of structural parameters of the system with temperature is reported from X-ray diffraction measurements and Rietveld analysis of the diffraction patterns. The change in local octahedral distortion due to 2% La deficiency is revealed through the shift in the phonon modes of GaO{sub 6} octahedra, in both orthorhombic and rhombohedral phase. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Pycnometric and Spectroscopic Studies of Red Phosphors Ca{sub (1-1.5x)}{sup 2+} WO{sub 4}:Eu{sub x}{sup 3+} Ca{sub (1}-{sub 2x)}{sup 2+} WO{sub 4}:Eu{sub x}{sup 3+},Na{sub x}{sup +}

Energy Technology Data Exchange (ETDEWEB)

Cho, Seonwoog [Silla Univ., Busan (Korea, Republic of)

2013-09-15

Red phosphors Ca{sub (1-1.5x)}Eu{sub x}WO{sub 4} and Ca{sub (1-2x)}Eu{sub x}Na{sub x}WO{sub 4} were synthesized with various concentrations x of Eu{sup 3+} ions by using a solid-state reaction method. The crystal structure of the red phosphors were found to be a tetragonal scheelite structure with space group I4{sub 1}/a. X-ray diffraction (XRD) results show the (112) main diffraction peak centered at 2θ = 28.71 .deg., and indicate that there is no basic structural deformation caused by the vacancies V{sub Ca}'' or the Eu{sup 3+} (and Na{sup +}) ions in the host crystals. Densities of Ca{sub (1.1.5x)}Eu{sub x}WO{sub 4} were measured on a (helium) gas pycnometer. Comparative results between the experimental and theoretical densities reveal that Eu{sup 3+} (and Na{sup +}) ions replace the Ca{sup 2+} ions in the host CaWO{sub 4}. Also, the photoluminescence (PL) emission and photoluminescence excitation (PLE) spectra show the optical properties of trivalent Eu{sup 3+} ions, not of divalent Eu{sup 2+}. Raman spectra exhibit that, without showing any difference before and after the doping of activators to the host material CaWO{sub 4}, all the gerade normal modes occur at the identical frequencies with the same shapes and weaker intensities after the substitution. However, the FT-IR spectra show that some of the ungerade normal modes have shifted positions and different shapes, caused by different masses of Eu{sup 3+} ions (or Na{sup +} ions, or V{sub Ca}'' vacancies) from Ca2{sup +}.

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

Indian Academy of Sciences (India)

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

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

International Nuclear Information System (INIS)

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

2005-01-01

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

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

Energy Technology Data Exchange (ETDEWEB)

Parrot, I. M. [Institut Laue-Langevin (ILL); Urban, Volker S [ORNL; Gardner, K. H. [DuPont Experimental Station; Forsyth, V. T. [Institut Laue Langevin and Keele University

2005-04-01

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

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

Science.gov (United States)

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

2005-08-01

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

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

Energy Technology Data Exchange (ETDEWEB)

Parrot, I.M. [Institut Laue Langevin, 6 Rue Jules Horowitz, 38042 Grenoble Cedex 9 (France); Institute of Science and Technology in Medicine, Keele University Medical School, Staffordshire ST4 7QB (United Kingdom); Urban, V. [Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, TN 37831-6100 (United States); Gardner, K.H. [Department of Materials Science and Engineering University of Delaware, Newark, DE 19719 (United States); Forsyth, V.T. [Institut Laue Langevin, 6 Rue Jules Horowitz, 38042 Grenoble Cedex 9 (France) and Institute of Science and Technology in Medicine, Keele University Medical School, Staffordshire ST4 7QB (United Kingdom)]. E-mail: tforsyth@ill.fr

2005-08-15

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

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

DEFF Research Database (Denmark)

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

2010-01-01

Recent advances in synchrotron based X-ray imaging and diffraction techniques offer interesting new possibilities for mapping 3D grain shapes and crystallographic orientations in different classes of polycrystalline materials. X-ray diffraction contrast tomography (DCT) is a monochromatic beam...... imaging technique combining the principles of X-ray micro-tomography and three-dimensional X-ray diffraction microscopy (3DXRD). DCT provides simultaneous access to 3D grain shape, crystallographic orientation and attenuation coefficient distribution at the micrometer length scale. The microtexture...

Structural and magnetic studies of tin doped α-Fe{sub 2}O{sub 3} (α-Sn{sub x}Fe{sub 2-x}O{sub 3}) nanoparticles prepared by microwave assisted synthesis

Energy Technology Data Exchange (ETDEWEB)

Bindu, K.; Nagaraja, H. S., E-mail: hosakoppa@gmail.com [Material Research Laboratory, Department of Physics, National Institute of Technology Karnataka, Surathkal, Srinivasnagar, Mangalore-575 025, Karnataka (India); Chowdhury, P. [Nanomaterials Research Laboratory, Surface Engineering Division, National Aerospace Laboratories, Council of Scientific and Industrial Research, Bangalore-560 017, Karnataka (India); Ajith, K. M. [Computational Physics Laboratory, Department of Physics, National Institute of Technology Karnataka, Surathkal, Srinivasnagar, Mangalore-575 025, Karnataka (India)

2016-05-06

Hematite (α-Fe{sub 2}O{sub 3}) doped with tetravalent ions have potential applications in various fields such as gas sensors, memories, energy storage devices because of their electrical and magnetic properties. Microwave assisted synthesis was used to prepare Tin doped α-Fe{sub 2}O{sub 3} [α-Sn{sub x}Fe{sub 2-x}O{sub 3}]. The structural and morphological studies were investigated using X-ray diffraction (XRD) and Scanning electron microscopy (SEM). XRD patterns revealed that α-Fe{sub 2}O{sub 3} and α-Sn{sub x}Fe{sub 2-x}O{sub 3} were having rhombohedral structure. The compositional study was done by Energy dispersive X-ray Spectroscopy (EDS). The magnetic properties were studied by Vibrating Sample Magnetometry (VSM). Results shows that the prepared samples were found to be antiferromagnetic in nature and the results are discussed in detail.

High-pressure synchrotron x-ray diffraction and infrared microspectroscopy: applications to dense hydrous phases

CERN Document Server

Liu, Z; Yang, H; Mao Ho Kwang; Hemley, R J

2002-01-01

Synchrotron x-ray diffraction (XRD) and infrared (IR) absorption spectra of hydrous and 'anhydrous' forms of phase X were measured to 30 GPa at room temperature. Three OH stretching modes were found in the hydrous phase, and surprisingly one sharp OH mode was observed in the previously characterized anhydrous phase. All OH stretching modes soften and broaden with increasing pressure and become very weak above approx 20 GPa. XRD indicates that the crystal structure remains stable up to 30 GPa. Combining IR absorption and XRD results, the behaviour is attributed to pressure-induced distortion of the Si sub 2 O sub 7 groups and disorder of the hydrogen atoms. The bulk moduli of the hydrous and 'anhydrous' phases are in the region of 74 GPa.

Magnetic Properties of Nanocrystalline Fe{sub x}Cu{sub 1-x} Alloys Prepared by Ball Milling

Energy Technology Data Exchange (ETDEWEB)

Yousif, A.; Bouziane, K., E-mail: bouzi@squ.edu.om; Elzain, M. E. [Sultan Qaboos University, Physics Department, College of Science (Oman); Ren, X.; Berry, F. J. [The Open University, Department of Chemistry (United Kingdom); Widatallah, H. M. [Sudan Atomic Energy Commission, Institute of Nuclear Research (Sudan); Al Rawas, A.; Gismelseed, A.; Al-Omari, I. A. [Sultan Qaboos University, Physics Department, College of Science (Oman)

2004-12-15

X-ray diffraction, Moessbauer and magnetization measurements were used to study Fe{sub x}Cu{sub 1-x} alloys prepared by ball-milling. The X-ray data show the formation of a nanocrystalline Fe-Cu solid solution. The samples with x{>=}0.8 and x{<=}0.5 exhibit bcc or fcc phase, respectively. Both the bcc and fcc phases are principally ferromagnetic for x{>=}0.2, but the sample with x=0.1 remains paramagnetic down to 78 K. The influence of the local environment on the hyperfine parameters and the local magnetic moment are discussed using calculations based on the discrete-variational method in the local density approximation.

Zn{sub x-1}Cu{sub x}Mn{sub 2}O{sub 4} spinels; synthesis, structural characterization and electrical evaluation

Energy Technology Data Exchange (ETDEWEB)

Mendez M, F.; Lima, E.; Bosch, P.; Pfeiffer, H. [UNAM, Instituto de Investigaciones en Materiales, Circuito Exterior, Ciudad Universitaria, 04510 Mexico D. F. (Mexico); Gonzalez, F., E-mail: pfeiffer@iim.unam.m [Universidad Autonoma Metropolitana, Unidad Iztapalapa, Av. San Rafael Atlixco No. 186, Col. Vicentina, 09340 Mexico D. F. (Mexico)

2010-07-01

This work presents the structural characterization and electrical evaluation of Zn{sub x-1}Cu{sub x}Mn{sub 2}O{sub 4} spinels, which are materials presented as secondary phases into the vari stor ceramic systems. Samples were analyzed by X-ray diffraction, solid-state nuclear magnetic resonance, infrared spectroscopy, scanning electron microscopy and impedance spectroscopy. Although, the addition of copper to the ZnMn{sub 2}O{sub 4} spinel did not produce morphological changes, the structure and electrical behaviors changed considerably. Structurally, copper addition induced the formation of partial inverse spinels, and its addition increases significantly the electrical conductivity. Therefore, the formation of Zn{sub x-1}Cu{sub x}Mn{sub 2}O{sub 4} spinels, as secondary phases into the vari stor materials, may compromise significantly the vari stor efficiency. (Author)

Quantitative analysis of minerals by X-ray diffraction

International Nuclear Information System (INIS)

Pietroluongo, L.R.V.; Veiga, M.M. da

1982-01-01

Considerations about the X-ray diffraction technique for quantitative analyses are made; some experiments carried out at CETEM - Centro de Tecnologia Mineral (Rio de Janeiro, Brazil) with synthetic samples and real samples of diatomites (from northeastern region of Brazil) are described. Quartz quantification has been a problem for analytical chemists and is of great importance to the industries which use this raw material. Comments are made about the main factors influencing the intensity of diffracted X-rays, such as: the crystallinity of the mineral phase; the granulometry, the preferential orientation; sample preparation and pressing, the chemical composition of standards and experimental analytical conditions. Several analytical methods used are described: direct measurement of the height or area of a peak resulting from a particular reflection and comparison with a pre-calibrated curve; method of sequential addition of the mineral of interest in the sample and extrapolation of results for ZERO addition; methods of external and internal standards. (C.L.B.) [pt

The equation of state of PbTiO sub 3 up to 37 GPa: a synchrotron x-ray powder diffraction study

CERN Document Server

Sani, A; Levy, D

2002-01-01

High-pressure synchrotron x-ray powder diffraction patterns were collected using ID09 of ESRF (Grenoble, France) for a powder sample of PbTiO sub 3 , placed in a diamond anvil cell. The patterns were collected at room temperature using nitrogen (up to 37 GPa) and methanol-ethanol solution (up to 7 GPa) as pressure-transmitting media. The bulk moduli were calculated for the first time using the Vinet equation of state and they were compared to those of isostructural compounds. The trend of the spontaneous polarization as a function of pressure confirms that the ferroelectric-paraelectric phase transition at 11.2 GPa possesses a second-order character.

Reflectivity and diffraction of X rays applied to organic thin films

International Nuclear Information System (INIS)

Rieutord, Francois

1987-01-01

This research thesis reports the study of organic thin films by using X-ray-based technologies, and more particularly X-ray reflectivity. After some recalls on X ray diffraction, and on the fabrication of Langmuir-Blodgett films, the author shows how, by combining three X-ray-based techniques, it is possible to study a volume structure of a thin film. He describes the technique of measurement by X- ray reflexivity, its experimental implementation, and methods for result interpretation. In the next part, the author reports the study of peculiar interference effects which are noticed in reflexivity on Langmuir-Blodgett films, and then describes the nature of these films by correlating results of X ray reflexivity with direct observations performed by electronic microscopy on replica [fr

Synthesis of compositionally controllable Cu{sub 2}(Sn{sub 1−x}Ge{sub x})S{sub 3} nanocrystals with tunable band gaps

Energy Technology Data Exchange (ETDEWEB)

Liang, Qingshuang, E-mail: lqs671@163.com [Jilin University, State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, College of Chemistry (China)

2016-06-15

In this work, we show that compositionally controlled Cu{sub 2}(Sn{sub 1–x}Ge{sub x})S{sub 3} nanocrystals can be successfully synthesized by the hot-injection method through careful tuning the Ge/(Sn+Ge) precursor ratio. The band gaps of the resultant nanocrystals are demonstrated to be linearly tuned from 1.45 to 2.33 eV by adjusting the composition parameter x of the Ge/(Sn+Ge) ratio from 0.0 to 1.0. The crystalline structures of the resultant NCs have been studied by the X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), select area electron diffraction (SAED), and Raman spectroscopy. A ligand exchange procedure is further performed to replace the native ligands on the surface of the NCs with sulfur ions. The photoresponsive behavior indicates the potential use of as-prepared Cu{sub 2}(Sn{sub 1–x}Ge{sub x})S{sub 3} nanocrystals in solar energy conversion systems. The synthesis of compositionally controlled Cu{sub 2}(Sn{sub 1–x}Ge{sub x})S{sub 3} nanocrystals reported herein provides a way for probing the effect of Ge inclusion in the Cu-Sn-S system thin films.

Structural, magnetic and transport properties of Pb{sub 2}Cr{sub 1+x}Mo{sub 1−x}O{sub 6} (−1≤x≤1/3)

Energy Technology Data Exchange (ETDEWEB)

Zhao, H.F. [Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China); School of Mathematics and Physics, University of Science and Technology, Beijing 100083 (China); Cao, L.P. [Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China); Song, Y.J. [Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China); School of Mathematics and Physics, University of Science and Technology, Beijing 100083 (China); Feng, S.M.; Shen, X. [Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China); Ni, X.D. [School of Mathematics and Physics, University of Science and Technology, Beijing 100083 (China); Yao, Y.; Wang, Y.G. [Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China); Wang, R.M. [School of Mathematics and Physics, University of Science and Technology, Beijing 100083 (China); Jin, C.Q. [Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China); Yu, R.C., E-mail: rcyu@aphy.iphy.ac.cn [Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China); School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049 (China)

2017-02-15

Pb{sub 2}Cr{sub 1+x}Mo{sub 1-x}O{sub 6} (−1≤x≤1/3) samples were synthesized via a high pressure and high temperature route. X-ray diffraction results suggest the samples crystallize in a disordered double perovskite structure (Pm-3m). X-ray photoemission spectroscopy results confirm the presence of Mo{sup 4+} for x=−1 and Mo{sup 6+} for x=1/3. The measured magnetic and electrical properties exhibit systematic change with increasing x. - Highlights: • A series of Pb{sub 2}Cr{sub 1+x}Mo{sub 1−x}O{sub 6} samples were synthesized under high pressure. • Magnetic and electrical properties of the series samples were investigated. • Valence states of Cr and Mo were determined through the analyses of XRD and XPS results. • Ground state of PbMoO{sub 3} were determined through the transport study and first-principles calculations.

Determination of the hydrogen positions in the novel barium boroarsenate Ba[B{sub 2}As{sub 2}O{sub 8}(OH){sub 2}] by combined single crystal X-ray and powder neutron investigations

Energy Technology Data Exchange (ETDEWEB)

Lieb, Alexandra [School of Chemistry, University of Southampton (United Kingdom); Fakultaet fuer Verfahrens- und Systemtechnik, Lehrstuhl fuer Technische Chemie, Otto-von-Guericke-Universitaet, Magdeburg (Germany); Weller, Mark T. [School of Chemistry, University of Southampton (United Kingdom); Department of Chemistry, University of Bath (United Kingdom)

2017-11-17

The boroarsenate Ba[B{sub 2}As{sub 2}O{sub 8}(OH){sub 2}] was obtained by the reaction of NH{sub 4}H{sub 2}AsO{sub 4}, B(OH){sub 3} and BaBr{sub 2}.2H{sub 2}O in the melt. Ba[B{sub 2}As{sub 2}O{sub 8}(OH){sub 2}] was obtained as thin colorless needles, together with spherical crystals of BAsO{sub 4} as by-product, grown on a pellet of Ba[BAsO{sub 5}]. The products could be separated mechanically. For neutron scattering experiments a sample was prepared with {sup 11}B(OH){sub 3} as a starting material. The crystal structure of Ba[B{sub 2}As{sub 2}O{sub 8}(OH){sub 2}] was determined by single-crystal X-ray diffraction and exhibits a layer structure with an unprecedented layer topology. The exact positions of the hydrogen atoms were determined using combined single-crystal X-ray and powder neutron diffraction investigations. Ba[B{sub 2}As{sub 2}O{sub 8}(OH){sub 2}] was further characterized by IR spectroscopy and EDX analysis. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Magnetic and Structural Properties of the Mechanically Alloyed Nd{sub 2}(Fe{sub 100-x}Nb{sub x}){sub 14}B System

Energy Technology Data Exchange (ETDEWEB)

Lozano, D. Oyola, E-mail: doyola@ut.edu.co [University of Tolima, Department of Physics (Colombia); Zamora, L. E.; Perez Alcazar, G. A. [University of Valle, Department of Physics (Colombia); Rojas, Y. A.; Bustos, H. [University of Tolima, Department of Physics (Colombia); Greneche, J. M. [UMR CNRS 6087, Laboratoire de Physique de l' Etat Condense (France)

2005-02-15

In this work we report the magnetic and structural properties obtained by Moessbauer spectrometry, Vibrating Sample Magnetometer and X-ray diffraction of milled powders with initial composition Nd{sub 2}(Fe{sub 100-x}Nb{sub x}){sub 14}B with x = 0 and x = 4. The mixtures were ball milled for different times up to 240 h. Structural and microstructural parameters were derived from high statistics X-ray patterns and discussed as a function of milling time. The Moessbauer spectra of the samples were fitted by means of a sextet and an hyperfine field distribution, associated to a pure iron phase ({alpha}-Fe) and a disordered iron-based phase, respectively. The {alpha}-Fe grain size decreases from 50 nm for 6 h up to 5 nm for 240 h milling time. The Vibrating Sample Magnetometer results allow to conclude that these samples behave as soft ferromagnets.

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

Science.gov (United States)

Eveno, Myriam; Duran, Adrian; Castaing, Jacques

2010-09-01

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

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

International Nuclear Information System (INIS)

Eveno, Myriam; Duran, Adrian; Castaing, Jacques

2010-01-01

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

New tubes and techniques for flash X-ray diffraction and high contrast radiography

International Nuclear Information System (INIS)

Charbonnier, F.M.; Barbour, J.P.; Brewster, J.L.

High energy electrons are particularly efficient in producing characteristic X-rays and soft polychromatic. A line of wide spectrum beryllium window flash X-ray tubes, ranging from 150 to 600kV, has been developed to exploit this property. Laue and Debye Scherrer flash X-ray diffraction patterns have been obtained using a single 30 ns pulse exposure. X-ray diffraction tests obtained are shown. Extremely high contrast flash radiography of small, low density objects has been obtained using industrial film without screen. Alternatively, particularly at high voltages and for subjects which include a broad range of materials and thicknesses, special film techniques can be used to produce extremely wide latitudes. Equipment, techniques and results are discussed

Diffractive X-Ray Telescopes

International Nuclear Information System (INIS)

Skinner, G.K.; Skinner, G.K

2010-01-01

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

X-ray diffraction and surface acoustic wave analysis of BST/Pt/TiO{sub 2}/SiO{sub 2}/Si thin films

Energy Technology Data Exchange (ETDEWEB)

Mseddi, Souhir; Hedi Ben Ghozlen, Mohamed [Laboratoire de Physique des Materiaux, Faculte des Sciences de Sfax, Universite de Sfax, 3018 Sfax (Tunisia); Njeh, Anouar [Unite de Physique, Informatique et Matematiques, Faculte des Sciences de Gafsa, Universite de Gafsa, 2112 Gafsa (Tunisia); Schneider, Dieter [Fraunhofer-Institut fuer Material- und Strahltechnologie, Winterbergstrasse 28, 1277 Dresden (Germany); Fuess, Hartmut [Institute of Materials Science, University of Technology, Petersenstr.23, 64287 Darmstadt (Germany)

2011-11-15

High dielectric constant and electrostriction property of (Ba, Sr)Ti0{sub 3} (BST) thin films result in an increasing interest for dielectric devices and microwave acoustic resonator. Barium strontium titanate (Ba{sub 0.645}Sr{sub 0.355}TiO{sub 3}) films of about 300 nm thickness are grown on Pt(111)/TiO{sub 2}/SiO{sub 2}/Si(001) substrates by rf magnetron sputtering deposition techniques. X-ray diffraction is applied for the microstructural characterization. The BST films exhibit a cubic perovskite structure with a dense and smooth surface. A laser acoustic waves (LA-waves) technique is used to generate surface acoustic waves (SAW) propagating in the BST films. Young's modulus E and the Poisson ratio {nu} of TiO{sub 2,} Pt and BST films in different propagation directions are derived from the measured dispersion curves. Estimation of BST elastics constants are served in SAW studies. Impact of stratification process on SAW, propagating along [100] and [110] directions of silicon substrate, has been interpreted on the basis of ordinary differential equation (ODE) and stiffness matrix method (SMM). A good agreement is observed between experimental and calculated dispersion curves. The performed calculations are strongly related to the implemented crystallographic data of each layer. Dispersion curves are found to be sensitive to the SAW propagation direction and the stratification process for the explored frequency ranges 50-250 MHz, even though it corresponds to a wave length clearly higher than the whole films thickness.

Structural refinement of artificial superlattices by the X-ray diffraction method

CERN Document Server

Ishibashi, Y; Tsurumi, T

1999-01-01

This paper reports a structural refinement of BaTiO sub 3 (BTO)/SrTiO sub 3 (STO) artificially superstructured thin films. The refinement was achieved by taking into account the effect of interdiffusion between BTO and STO. The samples were prepared by a molecular-beam epitaxy method on SrTiO sub 3 (001) substrate at 600 .deg. C. The phonon model was employed to simulate the X-ray diffraction (XRD) profiles. A discrepancy was observed in the intensities of the satellite peaks when the effect of the interdiffusion between BTO and STO was not incorporated in the simulation. In successive simulations, the concentration profile due to the interdiffusion was first calculated according to Fick's second law, and then the coefficients of the Fourier series describing the lattice distortion and the modulation of the structure factor were determined. The XRD profiles thus simulated almost completely agreed with those observed. This indicates that XRD analysis with the calculation process proposed in this study will ena...

Fabrication of Cu{sub 2}ZnSn(S{sub x}Se{sub 1−x}){sub 4} solar cells by ethanol-ammonium solution process

Energy Technology Data Exchange (ETDEWEB)

Xue, Cong; Li, Jianmin; Wang, Yaguang; Jiang, Guoshun; Weifeng, Liu, E-mail: liuwf@ustc.edu.cn; Zhu, Changfei, E-mail: cfzhu@ustc.edu.cn

2016-10-15

Highlights: • The CBD precipitates were utilized to fabricate the CZTS/CZTSSe solar cells. • A solvent mixture of ethanol and ammonium hydroxide was used to form SnS-Cu2O-ZnS slurry. • Formation of CZTS/CZTSSe with good crystalline quality confirmed by XRD and Raman spectra. • CZTS and CZTSSe thin film solar cells obtained the best PCE of 1.99% and 2.95%, respectively. - Abstract: In this paper, Cu{sub 2}ZnSn(S{sub x}Se{sub 1−x}){sub 4} precursor films were produced by doctor blade process from SnS-Cu{sub 2}O-ZnS slurry. To prepare the slurry, SnS, ZnS and Cu{sub 2}O precipitates, which are outgrowths of stacked layer ZnS/Cu/SnS by CBD (chemical bath deposition)-annealing route, were dissolved in the mixture solvent of ethanol and NH{sub 3}·H{sub 2}O. Synthesized precursor films were then annealed at different conditions. The post-annealed films were characterized by means of scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Raman measurements and UV–vis–NIR spectroscopy. SEM studies reveal that the rough and relatively compact absorber thin films are obtained via the sulfidation and sulfidation-selenization processes. X-ray diffraction and Raman spectrum results verify that the obtained films are composed of Cu{sub 2}ZnSnS{sub 4} and Cu{sub 2}ZnSnSe{sub 4} phases, which have high absorbance in visible range and direct band gap energy of 1.01–1.47 eV. The best devices yield total area power conversion efficiency of 1.99% and 2.95% corresponding to Cu{sub 2}ZnSnS{sub 4} and Cu{sub 2}ZnSn(S{sub x}Se{sub 1−x}){sub 4} thin film solar cells under AM1.5 illumination without any anti-reflection layer.

Study of magnetic behavior in hexagonal-YMn{sub 1−x}Fe{sub x}O{sub 3} (x=0 and 0.2) nanoparticles using remanent magnetization curves

Energy Technology Data Exchange (ETDEWEB)

Chauhan, Samta; Singh, Amit Kumar; Srivastava, Saurabh Kumar; Chandra, Ramesh, E-mail: ramesfic@iitr.ac.in

2016-09-15

We have studied the magnetic behavior of YMn{sub 1−x}Fe{sub x}O{sub 3} (x=0 and 0.2) nanoparticles synthesized by conventional solid state reaction method. The as-synthesized nanoparticles were found to have hexagonal phase with P6{sub 3cm} space group confirmed by X-Ray diffraction. The particle size was found to be ~70 nm as confirmed by both X-Ray diffraction and Transmission Electron Microscopy. DC magnetization and memory effect measurements imply that the h-YMnO{sub 3} nanoparticles bear a resemblance to super spin-glass state following de Almeida–Thouless like behavior which is being suppressed by Fe-doping. The Fe-doping in YMnO{sub 3} enhances the antiferromagnetic (AFM) transition temperature T{sub N} to ~79 K and induces a new magnetic state due to the surface spins which is realized as diluted antiferromagnet in a field (DAFF) as explored by the thermoremanent and isothermoremanent magnetization measured with different applied magnetic field. - Highlights: • Magnetic behavior of h-YMn{sub 1−x}Fe{sub x}O{sub 3} (x=0 and 0.2) nanoparticles have been studied. • The nanoparticles (~70 nm) were synthesized by solid state reaction method. • Magnetic data reveal spin-glass behavior in YMnO{sub 3} which was suppressed in YMn{sub 0.8}Fe{sub 0.2}O{sub 3}. • The h-YMnO{sub 3} nanoparticles show memory effect and obey de-Almeida Thouless line. • TRM and IRM suggest spin glass nature for YMnO{sub 3}, while the YMn{sub 0.8}Fe{sub 0.2}O{sub 3} resembles DAFF.

Low charge state heavy ion production with sub-nanosecond laser.

Science.gov (United States)

Kanesue, T; Kumaki, M; Ikeda, S; Okamura, M

2016-02-01

We have investigated laser ablation plasma of various species using nanosecond and sub-nanosecond lasers for both high and low charge state ion productions. We found that with sub-nanosecond laser, the generated plasma has a long tail which has low charge state ions determined by an electrostatic ion analyzer even under the laser irradiation condition for highly charged ion production. This can be caused by insufficient laser absorption in plasma plume. This property might be suitable for low charge state ion production. We used a nanosecond laser and a sub-nanosecond laser for low charge state ion production to investigate the difference of generated plasma using the Zirconium target.

Low charge state heavy ion production with sub-nanosecond laser

Energy Technology Data Exchange (ETDEWEB)

Kanesue, T., E-mail: tkanesue@bnl.gov; Okamura, M. [Collider-Accelerator Department, Brookhaven National Laboratory, Upton, New York 11973 (United States); Kumaki, M. [Research Institute for Science and Engineering, Waseda University, Tokyo 169-8555 (Japan); Nishina Center for Accelerator-Based Science, RIKEN, Saitama 351-0198 (Japan); Ikeda, S. [Nishina Center for Accelerator-Based Science, RIKEN, Saitama 351-0198 (Japan); Interdisciplinary Graduate School of Science and Engineering, Tokyo Institute of Technology, Kanagawa 226-8503 (Japan)

2016-02-15

We have investigated laser ablation plasma of various species using nanosecond and sub-nanosecond lasers for both high and low charge state ion productions. We found that with sub-nanosecond laser, the generated plasma has a long tail which has low charge state ions determined by an electrostatic ion analyzer even under the laser irradiation condition for highly charged ion production. This can be caused by insufficient laser absorption in plasma plume. This property might be suitable for low charge state ion production. We used a nanosecond laser and a sub-nanosecond laser for low charge state ion production to investigate the difference of generated plasma using the Zirconium target.

Solvent exchange in a metal–organic framework single crystal monitored by dynamic in situ X-ray diffraction

Energy Technology Data Exchange (ETDEWEB)

Cox, Jordan M.; Walton, Ian M.; Bateman, Gage; Benson, Cassidy A.; Mitchell, Travis; Sylvester, Eric; Chen, Yu-Sheng; Benedict, Jason B. (UC); (Buffalo)

2017-07-25

Understanding the processes by which porous solid-state materials adsorb and release guest molecules would represent a significant step towards developing rational design principles for functional porous materials. To elucidate the process of liquid exchange in these materials, dynamicin situX-ray diffraction techniques have been developed which utilize liquid-phase chemical stimuli. Using these time-resolved diffraction techniques, the ethanol solvation process in a flexible metal–organic framework [Co(AIP)(bpy)<sub>0.5sub>(H>2sub>O)]·2H<sub>2sub>O was examined. The measurements provide important insight into the nature of the chemical transformation in this system including the presence of a previously unreported neat ethanol solvate structure.

Thin film characterisation by advanced X-ray diffraction techniques

Energy Technology Data Exchange (ETDEWEB)

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

1996-09-01

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

Development and application of sub-nanosecond pulse-repeatable hard X-ray source

International Nuclear Information System (INIS)

Quan Lin; Fan Yajun; Tu Jing

2013-01-01

A multipurpose X-ray source was developed to meet the needs of multitask application such as radiation detection, radiation imaging and so on. The multipurpose X-ray source has characteristic of adjustable width and energy, pulse-repetition operation, ultra-short pulse and fine stability. Its rising time is close to 98.6 ps, the operation voltage reaches 425 kV, and the peak fluence rate exceeds 2.07 × 10 18 cm -2 · s -1 at 10 cm, which provides an ideal radiation environment for relevant application. (authors)

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

International Nuclear Information System (INIS)

Barbosa, Caroline M.; Azeredo, Soraia R.; Lopes, Ricardo T.; Souza, Sheila M.F.M de

2013-01-01

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

The contribution of valence unstable ytterbium states into kinetic properties of YbNi{sub 2-x}Ge{sub 2+x} and YbCu{sub 2-x}Si{sub 2+x}

Energy Technology Data Exchange (ETDEWEB)

Kuzhel, B.C. [Department of Physics, Ivan Franko National University of Lviv, 50 Dragomanow Str., 79005, Lviv (Ukraine)]. E-mail: kuzhelb@org.lviv.net; Shcherba, I.D. [Department of Physics, Ivan Franko National University of Lviv, 50 Dragomanow Str., 79005, Lviv (Ukraine); Institute of Techniques, Academy of Pedagogy, Podchorozych 2, 30-084, Krakow (Poland); Kravchenko, I.I. [Department of Physics, University of Florida, P.O. Box 118440, Gainesville, FL 32611 (United States)]. E-mail: kravch@phys.ufl.edu

2006-11-30

The intermetalic YbNi{sub 2-x}Ge{sub 2+x} (-0.25>=x>=0.25) and YbCu{sub 2-x}Si{sub 2+x} (-0.20>=x>=0.20) alloy systems (CeGa{sub 2}Al{sub 2} -type crystal structure) were studied by measuring X-ray absorption and diffraction at room temperatures as well as electrical resistivity and thermopower in the 4.2-300K temperature range. The temperature dependence of the contribution of valence unstable Yb ions to the total electrical resistance has been analyzed. The qualitative estimation of this contribution has been performed by utilizing the following equation:{delta}{rho}{sub Yb}(T)={rho}{sub exp}(T)-{rho}{sub YbCu{sub 2}Ge{sub 2}}(T)-{delta}{rho}{sub 4.2K},where {delta}{rho}{sub YbCu{sub 2}Ge{sub 2}}(T) is the temperature dependence of YbCu{sub 2}Ge{sub 2} electrical resistance, {delta}{rho}{sub 4.2}={rho}{sub 4.2}(exp)-{rho}{sub 4.2}(YbCu{sub 2}Ge{sub 2})

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

Science.gov (United States)

Gibson, David M [Voorheesville, NY; Gibson, Walter M [Voorheesville, NY; Huang, Huapeng [Latham, NY

2007-06-26

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

Characteristics of a molybdenum X-pinch X-ray source as a probe source for X-ray diffraction studies

International Nuclear Information System (INIS)

Zucchini, F.; Chauvin, C.; Combes, P.; Sol, D.; Loyen, A.; Roques, B.; Grunenwald, J.; Bland, S. N.

2015-01-01

X-ray emission from a molybdenum X-pinch has been investigated as a potential probe for the high pressure states made in dynamic compression experiments. Studies were performed on a novel 300 kA, 400 ns generator which coupled the load directly to a low inductance capacitor and switch combination. The X-pinch load consisted of 4 crossed molybdenum wires of 13 μm diameter, crossed at an angle of 62°. The load height was 10 mm. An initial x-ray burst generated at the wire crossing point, radiated in the soft x-ray range (hυ < 10 keV). This was followed, 2–5 ns later, by at least one harder x-ray burst (hυ > 10 keV) whose power ranged from 1 to 7 MW. Time integrated spectral measurements showed that the harder bursts were dominated by K-alpha emission; though, a lower level, wide band continuum up to at least 30 keV was also present. Initial tests demonstrated that the source was capable of driving Laue diffraction experiments, probing uncompressed samples of LiF and aluminium

Simulations of X-ray diffraction of shock-compressed single-crystal tantalum with synchrotron undulator sources.

Science.gov (United States)

Tang, M X; Zhang, Y Y; E, J C; Luo, S N

2018-05-01

Polychromatic synchrotron undulator X-ray sources are useful for ultrafast single-crystal diffraction under shock compression. Here, simulations of X-ray diffraction of shock-compressed single-crystal tantalum with realistic undulator sources are reported, based on large-scale molecular dynamics simulations. Purely elastic deformation, elastic-plastic two-wave structure, and severe plastic deformation under different impact velocities are explored, as well as an edge release case. Transmission-mode diffraction simulations consider crystallographic orientation, loading direction, incident beam direction, X-ray spectrum bandwidth and realistic detector size. Diffraction patterns and reciprocal space nodes are obtained from atomic configurations for different loading (elastic and plastic) and detection conditions, and interpretation of the diffraction patterns is discussed.

Simulations of X-ray diffraction of shock-compressed single-crystal tantalum with synchrotron undulator sources

Energy Technology Data Exchange (ETDEWEB)

Tang, M. X.; Zhang, Y. Y.; E, J. C.; Luo, S. N.

2018-04-24

Polychromatic synchrotron undulator X-ray sources are useful for ultrafast single-crystal diffraction under shock compression. Here, simulations of X-ray diffraction of shock-compressed single-crystal tantalum with realistic undulator sources are reported, based on large-scale molecular dynamics simulations. Purely elastic deformation, elastic–plastic two-wave structure, and severe plastic deformation under different impact velocities are explored, as well as an edge release case. Transmission-mode diffraction simulations consider crystallographic orientation, loading direction, incident beam direction, X-ray spectrum bandwidth and realistic detector size. Diffraction patterns and reciprocal space nodes are obtained from atomic configurations for different loading (elastic and plastic) and detection conditions, and interpretation of the diffraction patterns is discussed.

Optical and magnetic resonance investigations of Zn{sub 1-} {sub x} Mn {sub x} O magnetic semiconductors

Energy Technology Data Exchange (ETDEWEB)

Zhang Huawei [Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050 (China); Graduate School of the Chinese Academy of Sciences, Beijing 100049 (China); Shi Erwei [Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050 (China); Chen Zhizhan [Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050 (China)]. E-mail: zzchen@mail.sic.ac.cn; Liu Xuechao [Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050 (China); Graduate School of the Chinese Academy of Sciences, Beijing 100049 (China); Xiao Bing [Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050 (China); Song Lixin [Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050 (China)

2006-10-15

Zn{sub 1-} {sub x} Mn {sub x} O crystallites were synthesized by hydrothermal method. X-ray diffraction, UV-Vis absorption spectroscopy, and electron paramagnetic resonance (EPR) spectra confirm the substitution of Zn site by Mn{sup 2+} ion. The nonmonotonic variation of band gap exhibits that the short-ranged interactions between the d electrons of Mn and the s and p electrons of the host bands are dominated at lower Mn concentration (x). EPR spectra show that Mn{sup 2+} is in exchange interaction at higher x. By using a Curie-Weiss equation on the EPR data, it is found that the dominant magnetic property is antiferromagnetic for higher x, and paramagnetic for lower x.

The discovery of X-ray diffraction by crystals and its great impact on science

International Nuclear Information System (INIS)

Mai Zhenhong

2012-01-01

In April 1912, Friedrich, Knipping and Laue discovered X-ray diffraction in a CuSO 4 crystal. Later, Laue derived the famous Laue equations which explain the diffraction phenomenon. For this, Laue was awarded a Nobel Prize for Physics in 1914. In 1912 W. H. Bragg and W. L. Bragg received news of Laue 's discovery, and from X-ray diffraction experiments in a ZnS crystal they derived the famous Bragg equation. For this work, father and son were together awarded the Nobel Prize for Physics in 1915, To commemorate the 100th anniversary of the discovery of X-ray diffraction, this article reviews the important contributions of the early pioneers and their historic impact on science and technology worldwide. (author)

Growth of ω inclusions in Ti alloys: An X-ray diffraction study

International Nuclear Information System (INIS)

Šmilauerová, J.; Harcuba, P.; Pospíšil, J.; Matěj, Z.; Holý, V.

2013-01-01

We investigated the size and crystal structure of nanometer-sized ω inclusions in single crystals of β-Ti alloys by X-ray diffraction pole-figure measurements and reciprocal space mapping. We studied the topotactical relation of the β and ω crystal lattices, and from the positions and shapes of the diffraction maxima of the ω lattice determined the mean size of the ω inclusions and the misfit of the inclusion lattice with respect to the host lattice, as well as their changes during ageing. The lattice of the ω inclusions exhibits a large positive misfit already before ageing and the misfit is subsequently reduced during the ageing process. Using the theories of elasticity and X-ray scattering we simulated diffuse X-ray scattering around the β diffraction maxima and demonstrated that the diffuse scattering is caused mainly by local elastic strains in the β host phase around the ω inclusions

Synthesis of (Ga <sub>1–x> Zn <sub>x> )(N <sub>1–x> O <sub>x> ) with Enhanced Visible-Light Absorption and Reduced Defects by Suppressing Zn Volatilization

Energy Technology Data Exchange (ETDEWEB)

Chen, Dennis P.; Skrabalak, Sara E.

2016-04-18

(Ga<sub>1–x)(N>1–x> O <sub>x>) (GZNO) particles with enhanced optical absorption were synthesized by topotactic transformation of Zn²⁺/Ga³⁺ layered double hydroxides. This outcome was achieved by suppressing Zn volatilization during nitridation by maintaining a low partial pressure of O<sub>2sub> (p<sub>O2sub>). Zn-rich (x > 1/3) variants of GZNO were achieved and compared to those prepared by conventional ammonoylsis conditions. The optical absorption and structural properties of these samples were compared to those prepared in the absence of O<sub>2sub> by diffuse-reflectance spectroscopy and powder X-ray diffraction methods. Notably, suppression of Zn volatilization leads to smaller-band-gap materials (2.30 eV for x = 0.42 versus 2.71 eV for x = 0.21) and reduced structural defects. This synthetic route and set of characterizations provide useful structure–property studies of GZNO and potentially other oxynitrides of interest as photocatalysts.

Development of low temperature and high magnetic field X-ray diffraction facility

Energy Technology Data Exchange (ETDEWEB)

Shahee, Aga; Sharma, Shivani; Singh, K.; Lalla, N. P., E-mail: nplallaiuc82@gmail.com; Chaddah, P. [UGC-DAE Consortium for Scientific Research, University campus, Khandwa Road, Indore-452001 (India)

2015-06-24

The current progress of materials science regarding multifunctional materials (MFM) has put forward the challenges to understand the microscopic origin of their properties. Most of such MFMs have magneto-elastic correlations. To investigate the underlying mechanism it is therefore essential to investigate the structural properties in the presence of magnetic field. Keeping this in view low temperature and high magnetic field (LTHM) powder x-ray diffraction (XRD), a unique state-of-art facility in the country has been developed at CSR Indore. This setup works on symmetric Bragg Brentano geometry using a parallel incident x-ray beam from a rotating anode source working at 17 kW. Using this one can do structural studies at non-ambient conditions i.e. at low- temperatures (2-300 K) and high magnetic field (+8 to −8 T). The available scattering angle ranges from 5° to 115° 2θ with a resolution better than 0.1°. The proper functioning of the setup has been checked using Si sample. The effect of magnetic field on the structural properties has been demonstrated on Pr{sub 0.5}Sr{sub 0.5}MnO{sub 3} sample. Clear effect of field induced phase transition has been observed. Moreover, the effect of zero field cooled and field cooled conditions is also observed.

Biological imaging by soft X-ray diffraction microscopy