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Sample records for diffraction analysis rentgenostrukturnyj

  1. A QCD analysis of ZEUS diffractive data

    Energy Technology Data Exchange (ETDEWEB)

    Chekanov, S.; Derrick, M.; Magill, S. [Argonne National Laboratory, Argonne, IL (US)] (and others)

    2009-11-15

    ZEUS inclusive diffractive cross-section measurements have been used in a DGLAP next-to-leading-order QCD analysis to extract the diffractive parton distribution functions. Data on diffractive dijet production in deep inelastic scattering have also been included to constrain the gluon density. Predictions based on the extracted parton densities are compared to diffractive charm and dijet photoproduction data. (orig.)

  2. A QCD analysis of ZEUS diffractive data

    International Nuclear Information System (INIS)

    Chekanov, S.; Derrick, M.; Magill, S.

    2009-11-01

    ZEUS inclusive diffractive cross-section measurements have been used in a DGLAP next-to-leading-order QCD analysis to extract the diffractive parton distribution functions. Data on diffractive dijet production in deep inelastic scattering have also been included to constrain the gluon density. Predictions based on the extracted parton densities are compared to diffractive charm and dijet photoproduction data. (orig.)

  3. Tolerance analysis on diffraction efficiency and polychromatic integral diffraction efficiency for harmonic diffractive optics

    Science.gov (United States)

    Shan, Mao

    2016-10-01

    In this dissertation, the mathematical model of effect of manufacturing errors including microstructure relative height error and relative width error on diffraction efficiency for the harmonic diffractive optical elements (HDEs) is set up. According to the expression of the phase delay and diffraction efficiency of the HDEs, the expression of diffraction efficiency of refraction and diffractive optical element with the microstructure height and periodic width errors in fabrication process is presented in this paper. Furthermore, the effect of manufacturing errors on diffraction efficiency for the harmonic diffractive optical elements is studied, and diffraction efficiency change is analyzed as the relative microstructure height-error in the same and in the opposite sign as well as relative width-error in the same and in the opposite sign. Example including infrared wavelength with materials GE has been discussed in this paper. Two kinds of manufacturing errors applied in 3.7 4.3um middle infrared and 8.7-11.5um far infrared optical system which results in diffraction efficiency and PIDE of HDEs are studied. The analysis results can be used for manufacturing error control in micro-structure height and periodic width. Results can be used for HDEs processing.

  4. The analysis of powder diffraction data

    International Nuclear Information System (INIS)

    David, W.I.F.; Harrison, W.T.A.

    1986-01-01

    The paper reviews neutron powder diffraction data analysis, with emphasis on the structural aspects of powder diffraction and the future possibilities afforded by the latest generation of very high resolution neutron and x-ray powder diffractometers. Traditional x-ray powder diffraction techniques are outlined. Structural studies by powder diffraction are discussed with respect to the Rietveld method, and a case study in the Rietveld refinement method and developments of the Rietveld method are described. Finally studies using high resolution powder diffraction at the Spallation Neutron Source, ISIS at the Rutherford Appleton Laboratory are summarized. (U.K.)

  5. Diffraction analysis of the microstructure of materials

    CERN Document Server

    Scardi, Paolo

    2004-01-01

    Diffraction Analysis of the Microstructure of Materials provides an overview of diffraction methods applied to the analysis of the microstructure of materials. Since crystallite size and the presence of lattice defects have a decisive influence on the properties of many engineering materials, information about this microstructure is of vital importance in developing and assessing materials for practical applications. The most powerful and usually non-destructive evaluation techniques available are X-ray and neutron diffraction. The book details, among other things, diffraction-line broadening methods for determining crystallite size and atomic-scale strain due, e.g. to dislocations, and methods for the analysis of residual (macroscale) stress. The book assumes only a basic knowledge of solid-state physics and supplies readers sufficient information to apply the methods themselves.

  6. Diffraction analysis of customized illumination technique

    Science.gov (United States)

    Lim, Chang-Moon; Kim, Seo-Min; Eom, Tae-Seung; Moon, Seung Chan; Shin, Ki S.

    2004-05-01

    Various enhancement techniques such as alternating PSM, chrome-less phase lithography, double exposure, etc. have been considered as driving forces to lead the production k1 factor towards below 0.35. Among them, a layer specific optimization of illumination mode, so-called customized illumination technique receives deep attentions from lithographers recently. A new approach for illumination customization based on diffraction spectrum analysis is suggested in this paper. Illumination pupil is divided into various diffraction domains by comparing the similarity of the confined diffraction spectrum. Singular imaging property of individual diffraction domain makes it easier to build and understand the customized illumination shape. By comparing the goodness of image in each domain, it was possible to achieve the customized shape of illumination. With the help from this technique, it was found that the layout change would not gives the change in the shape of customized illumination mode.

  7. Bragg's Law diffraction simulations for electron backscatter diffraction analysis

    International Nuclear Information System (INIS)

    Kacher, Josh; Landon, Colin; Adams, Brent L.; Fullwood, David

    2009-01-01

    In 2006, Angus Wilkinson introduced a cross-correlation-based electron backscatter diffraction (EBSD) texture analysis system capable of measuring lattice rotations and elastic strains to high resolution. A variation of the cross-correlation method is introduced using Bragg's Law-based simulated EBSD patterns as strain free reference patterns that facilitates the use of the cross-correlation method with polycrystalline materials. The lattice state is found by comparing simulated patterns to collected patterns at a number of regions on the pattern using the cross-correlation function and calculating the deformation from the measured shifts of each region. A new pattern can be simulated at the deformed state, and the process can be iterated a number of times to converge on the absolute lattice state. By analyzing an iteratively rotated single crystal silicon sample and recovering the rotation, this method is shown to have an angular resolution of ∼0.04 o and an elastic strain resolution of ∼7e-4. As an example of applications, elastic strain and curvature measurements are used to estimate the dislocation density in a single grain of a compressed polycrystalline Mg-based AZ91 alloy.

  8. Quantitative phase analysis by neutron diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Chang Hee; Song, Su Ho; Lee, Jin Ho; Shim, Hae Seop [Korea Atomic Energy Research Institute, Taejon (Korea)

    1999-06-01

    This study is to apply quantitative phase analysis (QPA) by neutron diffraction to the round robin samples provided by the International Union of Crystallography(IUCr). We measured neutron diffraction patterns for mixed samples which have several different weight percentages and their unique characteristic features. Neutron diffraction method has been known to be superior to its complementary methods such as X-ray or Synchrotron, but it is still accepted as highly reliable under limited conditions or samples. Neutron diffraction has strong capability especially on oxides due to its scattering cross-section of the oxygen and it can become a more strong tool for analysis on the industrial materials with this quantitative phase analysis techniques. By doing this study, we hope not only to do one of instrument performance tests on our HRPD but also to improve our ability on the analysis of neutron diffraction data by comparing our QPA results with others from any advanced reactor facilities. 14 refs., 4 figs., 6 tabs. (Author)

  9. Reactor applications of quantitative diffraction analysis

    International Nuclear Information System (INIS)

    Feguson, I.F.

    1976-09-01

    Current work in quantitative diffraction analysis was presented under the main headings of: thermal systems, fast reactor systems, SGHWR applications and irradiation damage. Preliminary results are included on a comparison of various new instrumental methods of boron analysis as well as preliminary new results on Zircaloy corrosion, and materials transfer in liquid sodium. (author)

  10. Rietveld analysis, powder diffraction and cement

    International Nuclear Information System (INIS)

    Peterson, V.

    2002-01-01

    Full text: Phase quantification of cement is essential in its industrial use, however many methods are inaccurate and/or time consuming. Powder diffraction is one of the more accurate techniques used for quantitative phase analysis of cement. There has been an increase in the use of Rietveld refinement and powder diffraction for the analysis and phase quantification of cement and its components in recent years. The complex nature of cement components, existence of solid solutions, polymorphic variation of phases and overlapping phase peaks in diffraction patterns makes phase quantification of cements by powder diffraction difficult. The main phase in cement is alite, a solid solution of tricalcium silicate. Tricalcium silicate has been found to exist in seven modifications in three crystal systems, including triclinic, monoclinic, and rhombohedral structures. Hence, phase quantification of cements using Rietveld methods usually involves the simultaneous modelling of several tricalcium silicate structures to fit the complex alite phase. An industry ordinary Portland cement, industry and standard clinker, and a synthetic tricalcium silicate were characterised using neutron, laboratory x-ray and synchrotron powder diffraction. Diffraction patterns were analysed using full-profile Rietveld refinement. This enabled comparison of x-ray, neutron and synchrotron data for phase quantification of the cement and examination of the tricalcium silicate. Excellent Rietveld fits were achieved, however the results showed that the quantitative phase analysis results differed for some phases in the same clinker sample between various data sources. This presentation will give a short introduction about cement components including polymorphism, followed by the presentation of some problems in phase quantification of cements and the role of Rietveld refinement in solving these problems. Copyright (2002) Australian X-ray Analytical Association Inc

  11. Laser diffraction analysis of colloidal crystals

    Energy Technology Data Exchange (ETDEWEB)

    Sogami, Ikuo S.; Shinohara, Tadatomi; Yoshiyama, Tsuyoshi [Kyoto Sangyo Univ., Department of Physics, Kyoto (Japan)

    2001-10-01

    Laser diffraction analysis is made on crystallization in salt-free aqueous suspensions of highly-charged colloidal particles for semi-dilute specimens of concentration 0.1-10.0 vol%. Kossel diffraction patterns which represent faithfully accurate information on lattice symmetries in the suspensions enable us to investigate the time evolution of colloidal crystals. The results show that the crystallization proceeds by way of the following intermediate phase transitions: two-dimensional hcp structure {yields} random layer structure {yields} layer structure with one sliding degree of freedom {yields} stacking disorder structure {yields} stacking structure with multivariant periodicity {yields} fcc twin structure with twin plane (111) {yields} normal fcc structure {yields} bcc twin structure with twin plane (11-bar2) or (1-bar12) {yields} normal bcc structure. For concentrated suspensions (>2 vol %), the phase transition ceases to proceed at the normal fcc structure. (author)

  12. Laser diffraction analysis of colloidal crystals

    International Nuclear Information System (INIS)

    Sogami, Ikuo S.; Shinohara, Tadatomi; Yoshiyama, Tsuyoshi

    2001-01-01

    Laser diffraction analysis is made on crystallization in salt-free aqueous suspensions of highly-charged colloidal particles for semi-dilute specimens of concentration 0.1-10.0 vol%. Kossel diffraction patterns which represent faithfully accurate information on lattice symmetries in the suspensions enable us to investigate the time evolution of colloidal crystals. The results show that the crystallization proceeds by way of the following intermediate phase transitions: two-dimensional hcp structure → random layer structure → layer structure with one sliding degree of freedom → stacking disorder structure → stacking structure with multivariant periodicity → fcc twin structure with twin plane (111) → normal fcc structure → bcc twin structure with twin plane (11-bar2) or (1-bar12) → normal bcc structure. For concentrated suspensions (>2 vol %), the phase transition ceases to proceed at the normal fcc structure. (author)

  13. Quantitative measurement of phase variation amplitude of ultrasonic diffraction grating based on diffraction spectral analysis

    Energy Technology Data Exchange (ETDEWEB)

    Pan, Meiyan, E-mail: yphantomohive@gmail.com; Zeng, Yingzhi; Huang, Zuohua, E-mail: zuohuah@163.com [Laboratory of Quantum Engineering and Quantum Materials, School of Physics and Telecommunication Engineering, South China Normal University, Guangzhou, Guangdong 510006 (China)

    2014-09-15

    A new method based on diffraction spectral analysis is proposed for the quantitative measurement of the phase variation amplitude of an ultrasonic diffraction grating. For a traveling wave, the phase variation amplitude of the grating depends on the intensity of the zeroth- and first-order diffraction waves. By contrast, for a standing wave, this amplitude depends on the intensity of the zeroth-, first-, and second-order diffraction waves. The proposed method is verified experimentally. The measured phase variation amplitude ranges from 0 to 2π, with a relative error of approximately 5%. A nearly linear relation exists between the phase variation amplitude and driving voltage. Our proposed method can also be applied to ordinary sinusoidal phase grating.

  14. Holographic analysis of diffraction structure factors

    International Nuclear Information System (INIS)

    Marchesini, S.; Bucher, J.J.; Shuh, D.K.; Fabris, L.; Press, M.J.; West, M.W.; Hussain, Z.; Mannella, N.; Fadley, C.S.; Van Hove, M.A.; Stolte, W.C.

    2002-01-01

    We combine the theory of inside-source/inside-detector x-ray fluorescence holography and Kossel lines/ x ray standing waves in kinematic approximation to directly obtain the phases of the diffraction structure factors. The influence of Kossel lines and standing waves on holography is also discussed. We obtain partial phase determination from experimental data obtaining the sign of the real part of the structure factor for several reciprocal lattice vectors of a vanadium crystal

  15. Comparative study of macrotexture analysis using X-ray diffraction and electron backscattered diffraction techniques

    International Nuclear Information System (INIS)

    Serna, Marilene Morelli

    2002-01-01

    The macrotexture is one of the main characteristics in metallic materials, which the physical properties depend on the crystallographic direction. The analysis of the macrotexture to middles of the decade of 80 was just accomplished by the techniques of Xray diffraction and neutrons diffraction. The possibility of the analysis of the macrotexture using, the technique of electron backscattering diffraction in the scanning electronic microscope, that allowed to correlate the measure of the orientation with its location in the micro structure, was a very welcome tool in the area of engineering of materials. In this work it was studied the theoretical aspects of the two techniques and it was used of both techniques for the analysis of the macrotexture of aluminum sheets 1050 and 3003 with intensity, measured through the texture index 'J', from 2.00 to 5.00. The results obtained by the two techniques were shown reasonably similar, being considered that the statistics of the data obtained by the technique of electron backscatter diffraction is much inferior to the obtained by the X-ray diffraction. (author)

  16. Phasor analysis of binary diffraction gratings with different fill factors

    International Nuclear Information System (INIS)

    MartInez, Antonio; Sanchez-Lopez, Ma del Mar; Moreno, Ignacio

    2007-01-01

    In this work, we present a simple analysis of binary diffraction gratings with different slit widths relative to the grating period. The analysis is based on a simple phasor technique directly derived from the Huygens principle. By introducing a slit phasor and a grating phasor, the intensity of the diffracted orders and the grating's resolving power can be easily obtained without applying the usual Fourier transform operations required for these calculations. The proposed phasor technique is mathematically equivalent to the Fourier transform calculation of the diffraction order amplitude, and it can be useful to explain binary diffraction gratings in a simple manner in introductory physics courses. This theoretical analysis is illustrated with experimental results using a liquid crystal device to display diffraction gratings with different fill factors

  17. Phasor analysis of binary diffraction gratings with different fill factors

    Energy Technology Data Exchange (ETDEWEB)

    MartInez, Antonio [Departamento de Ciencia de Materiales, Optica y TecnologIa Electronica, Universidad Miguel Hernandez, 03202 Elche (Spain); Sanchez-Lopez, Ma del Mar [Instituto de BioingenierIa y Departamento de Fisica y Arquitectura de Computadores, Universidad Miguel Hernandez, 03202 Elche (Spain); Moreno, Ignacio [Departamento de Ciencia de Materiales, Optica y TecnologIa Electronica, Universidad Miguel Hernandez, 03202 Elche (Spain)

    2007-09-11

    In this work, we present a simple analysis of binary diffraction gratings with different slit widths relative to the grating period. The analysis is based on a simple phasor technique directly derived from the Huygens principle. By introducing a slit phasor and a grating phasor, the intensity of the diffracted orders and the grating's resolving power can be easily obtained without applying the usual Fourier transform operations required for these calculations. The proposed phasor technique is mathematically equivalent to the Fourier transform calculation of the diffraction order amplitude, and it can be useful to explain binary diffraction gratings in a simple manner in introductory physics courses. This theoretical analysis is illustrated with experimental results using a liquid crystal device to display diffraction gratings with different fill factors.

  18. Frequency analysis for modulation-enhanced powder diffraction.

    Science.gov (United States)

    Chernyshov, Dmitry; Dyadkin, Vadim; van Beek, Wouter; Urakawa, Atsushi

    2016-07-01

    Periodic modulation of external conditions on a crystalline sample with a consequent analysis of periodic diffraction response has been recently proposed as a tool to enhance experimental sensitivity for minor structural changes. Here the intensity distributions for both a linear and nonlinear structural response induced by a symmetric and periodic stimulus are analysed. The analysis is further extended for powder diffraction when an external perturbation changes not only the intensity of Bragg lines but also their positions. The derived results should serve as a basis for a quantitative modelling of modulation-enhanced diffraction data measured in real conditions.

  19. Small area analysis using micro-diffraction techniques

    International Nuclear Information System (INIS)

    Goehner, Raymond P.; Tissot, Ralph G. Jr.; Michael, Joseph R.

    2000-01-01

    An overall trend toward smaller electronic packages and devices makes it increasingly important and difficult to obtain meaningful diffraction information from small areas. X-ray micro-diffraction, electron back-scattered diffraction (EBSD) and Kossel are micro-diffraction techniques used for crystallographic analysis including texture, phase identification and strain measurements. X-ray micro-diffraction primarily is used for phase analysis and residual strain measurements. X-ray micro-diffraction primarily is used for phase analysis and residual strain measurements of areas between 10 microm to 100 microm. For areas this small glass capillary optics are used for producing a usable collimated x-ray beam. These optics are designed to reflect x-rays below the critical angle therefore allowing for larger solid acceptance angle at the x-ray source resulting in brighter smaller x-ray beams. The determination of residual strain using micro-diffraction techniques is very important to the semiconductor industry. Residual stresses have caused voiding of the interconnect metal which then destroys electrical continuity. Being able to determine the residual stress helps industry to predict failures from the aging effects of interconnects due to this stress voiding. Stress measurements would be impossible using a conventional x-ray diffractometer; however, utilizing a 30 microm glass capillary these small areas are readily assessable for analysis. Kossel produces a wide angle diffraction pattern from fluorescent x-rays generated in the sample by an e-beam in a SEM. This technique can yield very precise lattice parameters for determining strain. Fig. 2 shows a Kossel pattern from a Ni specimen. Phase analysis on small areas is also possible using an energy dispersive spectrometer (EBSD) and x-ray micro-diffraction techniques. EBSD has the advantage of allowing the user to observe the area of interest using the excellent imaging capabilities of the SEM. An EDS detector has been

  20. Truncation in diffraction pattern analysis. Pt. 1

    International Nuclear Information System (INIS)

    Delhez, R.; Keijser, T.H. de; Mittemeijer, E.J.; Langford, J.I.

    1986-01-01

    An evaluation of the concept of a line profile is provoked by truncation of the range of intensity measurement in practice. The measured truncated line profile can be considered either as part of the total intensity distribution which peaks at or near the reciprocal-lattice points (approach 1), or as part of a component line profile which is confined to a single reciprocal-lattice point (approach 2). Some false conceptions in line-profile analysis can then be avoided and recipes can be developed for the extrapolation of the tails of the truncated line profile. Fourier analysis of line profiles, according to the first approach, implies a Fourier series development of the total intensity distribution defined within [l - 1/2, l + 1/2] (l indicates the node considered in reciprocal space); the second approach implies a Fourier transformation of the component line profile defined within [ - ∞, + ∞]. Exact descriptions of size broadening are provided by both approaches, whereas combined size and strain broadening can only be evaluated adequately within the first approach. Straightforward methods are given for obtaining truncation-corrected values for the average crystallite size. (orig.)

  1. Quantitative multiphase analysis of archaeological bronzes by neutron diffraction

    CERN Document Server

    Siano, S; Celli, M; Pini, R; Salimbeni, R; Zoppi, M; Kockelmann, W A; Iozzo, M; Miccio, M; Moze, O

    2002-01-01

    In this paper, we report the first investigation on the potentials of neutron diffraction to characterize archaeological bronze artifacts. The preliminary feasibility of phase and structural analysis was demonstrated on standardised specimens with a typical bronze alloy composition. These were realised through different hardening and annealing cycles, simulating possible ancient working techniques. The Bragg peak widths that resulted were strictly dependent on the working treatment, thus providing an important analytical element to investigate ancient making techniques. The diagnostic criteria developed on the standardised specimens were then applied to study two Etruscan museum pieces. Quantitative multiphase analysis by Rietveld refinement of the diffraction patterns was successfully demonstrated. Furthermore, the analysis of patterns associated with different artifact elements also yielded evidence for some peculiar perspective of the neutron diffraction diagnostics in archeometric applications. (orig.)

  2. ATALANTA: a multicomponent pulsed neutron diffraction analysis code

    International Nuclear Information System (INIS)

    Benham, M.J.; Ross, D.K.

    1986-01-01

    The analysis of powder diffraction patterns from metal hydrogen systems present certain problems which have been addressed in a restructured profile analysis program. The heart of this program, ATALANTA, is a routine which locates and processes small sections of the data field to which a minimal number of Bragg peaks contribute intensity. The analysis of a three component test data set is presented in order to demonstrate the method. (author)

  3. Diffraction imaging and velocity analysis using oriented velocity continuation

    KAUST Repository

    Decker, Luke

    2014-08-05

    We perform seismic diffraction imaging and velocity analysis by separating diffractions from specular reflections and decomposing them into slope components. We image slope components using extrapolation in migration velocity in time-space-slope coordinates. The extrapolation is described by a convection-type partial differential equation and implemented efficiently in the Fourier domain. Synthetic and field data experiments show that the proposed algorithm is able to detect accurate time-migration velocities by automatically measuring the flatness of events in dip-angle gathers.

  4. Development of materials science by Ab initio powder diffraction analysis

    International Nuclear Information System (INIS)

    Fujii, Kotaro

    2015-01-01

    Crystal structure is most important information to understand properties and behavior of target materials. Technique to analyze unknown crystal structures from powder diffraction data (ab initio powder diffraction analysis) enables us to reveal crystal structures of target materials even we cannot obtain a single crystal. In the present article, three examples are introduced to show the power of this technique in the field of materials sciences. The first example is dehydration/hydration of the pharmaceutically relevant material erythrocycin A. In this example, crystal structures of two anhydrous phases were determined from synchrotron X-ray powder diffraction data and their different dehydration/hydration properties were understood from the crystal structures. In the second example, a crystal structure of a three dimensional metal-organic-framework prepared by a mechanochemical reaction was determined from laboratory X-ray powder diffraction data and the reaction scheme has been revealed. In the third example, a crystal structure of a novel oxide-ion conductor of a new structure family was determined from synchrotron X-ray and neutron powder diffraction data which gave an important information to understand the mechanism of the oxide-ion conduction. (author)

  5. Analysis of XFEL serial diffraction data from individual crystalline fibrils

    Directory of Open Access Journals (Sweden)

    David H. Wojtas

    2017-11-01

    Full Text Available Serial diffraction data collected at the Linac Coherent Light Source from crystalline amyloid fibrils delivered in a liquid jet show that the fibrils are well oriented in the jet. At low fibril concentrations, diffraction patterns are recorded from single fibrils; these patterns are weak and contain only a few reflections. Methods are developed for determining the orientation of patterns in reciprocal space and merging them in three dimensions. This allows the individual structure amplitudes to be calculated, thus overcoming the limitations of orientation and cylindrical averaging in conventional fibre diffraction analysis. The advantages of this technique should allow structural studies of fibrous systems in biology that are inaccessible using existing techniques.

  6. A program for Warren-Averbach analysis of diffraction data

    International Nuclear Information System (INIS)

    Fan, Zhijian; Chen, Bo; Chen, Xiping

    2009-04-01

    X-ray or neutron diffraction experiment can provide microstructural information of crystalline materials. At the moment without the model of micro-structure, Warren-Averbach analysis is regarded as an important tool. For this purpose, a program of Warren-Averbach analysis has been developed. The pro- gram has nearly all basic functions, it can be conveniently used through a graphic user interface as well. In the end, the efficiency of the program is illustrated by an example of ceria. (authors)

  7. Profile analysis of neutron powder diffraction data at ISIS

    International Nuclear Information System (INIS)

    David, W.I.F.; Ibberson, R.M.; Matthewman, J.C.

    1992-05-01

    The aim of this manual is to document the current suite of time-of-flight neutron powder diffraction profile refinement programs available to ISIS users. Aspects of data collation and normalisation specific to the individual diffraction instruments are dealt with elsewhere. It will be assumed the user has produced a suitable data file (.DAT file) containing the profile data consisting of point by point values of the corrected diffraction profile across the pattern. The analysis of neutron powder diffraction data at ISIS by profile refinement utilises a suite of ''in-house'' written and supported programs based on the Cambridge Crystallography Subroutine Library (CCSL). A quick scan through the CCSL manual will give the user a general feel for the procedure to adopt in the use of the library and hence of the profile codes. The instructions documented in this handbook are complementary to those in the more specialist CCSL manual, and consequently go into no great detail regarding technical details of any of the CCSL routines. The programs may be run from each individual user account, for example [USER01], once the appropriate login procedure has been set-up by the instrument scientists. The programs are mostly activated by one line commands and only a basic knowledge of a VAX editor should be required; details can be found in the ''VAX primer'' available from Computer Support. (Author)

  8. Fourier-Based Diffraction Analysis of Live Caenorhabditis elegans.

    Science.gov (United States)

    Magnes, Jenny; Hastings, Harold M; Raley-Susman, Kathleen M; Alivisatos, Clara; Warner, Adam; Hulsey-Vincent, Miranda

    2017-09-13

    This manuscript describes how to classify nematodes using temporal far-field diffraction signatures. A single C. elegans is suspended in a water column inside an optical cuvette. A 632 nm continuous wave HeNe laser is directed through the cuvette using front surface mirrors. A significant distance of at least 20-30 cm traveled after the light passes through the cuvette ensures a useful far-field (Fraunhofer) diffraction pattern. The diffraction pattern changes in real time as the nematode swims within the laser beam. The photodiode is placed off-center in the diffraction pattern. The voltage signal from the photodiode is observed in real time and recorded using a digital oscilloscope. This process is repeated for 139 wild type and 108 "roller" C. elegans. Wild type worms exhibit a rapid oscillation pattern in solution. The "roller" worms have a mutation in a key component of the cuticle that interferes with smooth locomotion. Time intervals that are not free of saturation and inactivity are discarded. It is practical to divide each average by its maximum to compare relative intensities. The signal for each worm is Fourier transformed so that the frequency pattern for each worm emerges. The signal for each type of worm is averaged. The averaged Fourier spectra for the wild type and the "roller" C. elegans are distinctly different and reveal that the dynamic worm shapes of the two different worm strains can be distinguished using Fourier analysis. The Fourier spectra of each worm strain match an approximate model using two different binary worm shapes that correspond to locomotory moments. The envelope of the averaged frequency distribution for actual and modeled worms confirms the model matches the data. This method can serve as a baseline for Fourier analysis for many microscopic species, as every microorganism will have its unique Fourier spectrum.

  9. Bragg's Law diffraction simulations for electron backscatter diffraction analysis

    Energy Technology Data Exchange (ETDEWEB)

    Kacher, Josh, E-mail: jkacherbyu@gmail.com [Department of Mechanical Engineering, Brigham Young University, 455B Crabtree Technology Building, Provo, UT 84602 (United States); Landon, Colin; Adams, Brent L.; Fullwood, David [Department of Mechanical Engineering, Brigham Young University, 455B Crabtree Technology Building, Provo, UT 84602 (United States)

    2009-08-15

    In 2006, Angus Wilkinson introduced a cross-correlation-based electron backscatter diffraction (EBSD) texture analysis system capable of measuring lattice rotations and elastic strains to high resolution. A variation of the cross-correlation method is introduced using Bragg's Law-based simulated EBSD patterns as strain free reference patterns that facilitates the use of the cross-correlation method with polycrystalline materials. The lattice state is found by comparing simulated patterns to collected patterns at a number of regions on the pattern using the cross-correlation function and calculating the deformation from the measured shifts of each region. A new pattern can be simulated at the deformed state, and the process can be iterated a number of times to converge on the absolute lattice state. By analyzing an iteratively rotated single crystal silicon sample and recovering the rotation, this method is shown to have an angular resolution of {approx}0.04{sup o} and an elastic strain resolution of {approx}7e-4. As an example of applications, elastic strain and curvature measurements are used to estimate the dislocation density in a single grain of a compressed polycrystalline Mg-based AZ91 alloy.

  10. Analysis and interpretation of diffraction data from complex, anisotropic materials

    Science.gov (United States)

    Tutuncu, Goknur

    Most materials are elastically anisotropic and exhibit additional anisotropy beyond elastic deformation. For instance, in ferroelectric materials the main inelastic deformation mode is via domains, which are highly anisotropic crystallographic features. To quantify this anisotropy of ferroelectrics, advanced X-ray and neutron diffraction methods were employed. Extensive sets of data were collected from tetragonal BaTiO3, PZT and other ferroelectric ceramics. Data analysis was challenging due to the complex constitutive behavior of these materials. To quantify the elastic strain and texture evolution in ferroelectrics under loading, a number of data analysis techniques such as the single peak and Rietveld methods were used and their advantages and disadvantages compared. It was observed that the single peak analysis fails at low peak intensities especially after domain switching while the Rietveld method does not account for lattice strain anisotropy although it overcomes the low intensity problem via whole pattern analysis. To better account for strain anisotropy the constant stress (Reuss) approximation was employed within the Rietveld method and new formulations to estimate lattice strain were proposed. Along the way, new approaches for handling highly anisotropic lattice strain data were also developed and applied. All of the ceramics studied exhibited significant changes in their crystallographic texture after loading indicating non-180° domain switching. For a full interpretation of domain switching the spherical harmonics method was employed in Rietveld. A procedure for simultaneous refinement of multiple data sets was established for a complete texture analysis. To further interpret diffraction data, a solid mechanics model based on the self-consistent approach was used in calculating lattice strain and texture evolution during the loading of a polycrystalline ferroelectric. The model estimates both the macroscopic average response of a specimen and its hkl

  11. 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

  12. Diffraction stress analysis of thin films; investigating elastic grain interaction

    International Nuclear Information System (INIS)

    Kumar, A.

    2005-12-01

    This work is dedicated to the investigation of specimens exhibiting anisotropic microstructures (and thus macroscopic elastic anisotropy) and/or inhomogeneous microstructures, as met near surfaces and in textured materials. The following aspects are covered: (i) Analysis of specimens with direction-dependent (anisotropic) elastic grain-interaction. Elastic grain-interaction determines the distribution of stresses and strains over the (crystallographically) differently oriented grains of a mechanically stressed polycrystal and the mechanical and diffraction (X-ray) elastic constants (relating (diffraction) lattice strains to mechanical stresses). Grain interaction models that allow for anisotropic, direction-dependent grain interaction have been developed very recently. The notion 'direction-dependent' grain-interaction signifies that different grain-interaction constraints prevail along different directions in a specimen. Practical examples of direction-dependent grain interaction are the occurrence of surface anisotropy in thin films and the surface regions of bulk polycrystals and the occurrence of grain-shape (morphological) texture. In this work, for the first time, stress analyses of thin films have been performed on the basis of these newly developed grain-interaction models. It has also been demonstrated that the identification of the (dominant) source of direction-dependent grain interaction is possible. The results for the grain interaction have been discussed in the light of microstructural investigations of the specimens by microscopic techniques. (ii) Analysis of specimens with depth gradients: Diffraction stress analysis can be hindered if gradients of the stress state, the composition or the microstructure occur in the specimen under investigation, as the so-called information depth varies in the course of a traditional stress measurement: Ambiguous results are thus generally obtained. In this work, a strategy for stress measurements at fixed

  13. 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

  14. Soil texture analysis by laser diffraction - standardization needed

    DEFF Research Database (Denmark)

    Callesen, Ingeborg; Palviainen, M.; Kjønaas, O. Janne

    2017-01-01

    Soil texture is a central soil quality property. Laser diffraction (LD) for determination of particle size distribution (PSD) is now widespread due to easy analysis and low cost. However, pretreatment methods and interpretation of the resulting soil PSD’s are not standardized. Comparison of LD data...... with sedimentation and sieving data may cause misinterpretation and confusion. In literature that reports PSD’s based on LD, pretreatment methods, operating procedures and data methods are often underreported or not reported, although literature stressing the importance exists (e.g. Konert and Vandenberghe, 1997...... and many newer; ISO 13320:2009). PSD uncertainty caused by pretreatments and PSD bias caused by plate-shaped clay particles still calls for more method standardization work. If LD is used more generally, new pedotransfer functions for other soil properties (e.g water retention) based on sieving...

  15. ATLAS - analysis of time-of-flight diffraction data from liquid and amorphous samples

    International Nuclear Information System (INIS)

    Soper, A.K.; Howells, W.S.; Hannon, A.C.

    1989-05-01

    The purpose of this manual is to describe a package of data analysis routines which have been developed at the Rutherford Appleton Laboratory for the analysis of time-of-flight diffraction data from liquids, gases, and amorphous materials. There is no fundamental barrier to diffraction data being accurately analysed to structure factor or even pair correlation function within a very short time of the completion of the experiment. Section 1 describes the time-of-flight neutron diffraction experiment and looks at diffraction theory. Section 2 indicates the steps in data analysis of time-of-flight diffraction data and Section 3 gives details of how to run the procedures. (author)

  16. Qualitative analysis of powder x-ray diffraction data

    International Nuclear Information System (INIS)

    Raftery, T.

    1999-01-01

    Full text: The main task of qualitative analysis is the determination of the presence of major, minor and if practical trace phases in a sample. The attainment of this goal is dependent on the quality of alignment (line position and intensity) as well as quality of sample preparation. Identification is generally on the basis of structure and dependent on the use of reference patterns. There are inherent limitations to the use of reference patterns including lack of reference patterns for the phase of interest (rare), solid solutions or substitutions (likely) and poor quality of reference patterns (unusual). With multiphase samples, there are the added problems of line overlap or interference, determining minor or trace phases in the presence of major phases, the decrease of intensity with concentration and influence of mass absorption on intensities. Within multiphase samples there may be many phases, some of which are in low abundance. It is sometimes possible (and usually desirable) to fractionate the sample by some physical or chemical method (while attempting not to create new phases as a result). It is usually important and often critical to have available supplementary information about the sample - either chemical or physical, or a history of preparation or formation. A central issue is what constitutes a match. A match is an adequate accounting of the distribution of intensity in the diffraction pattern. The match can be thought of in terms of a sum of δ2θ (or δd/d) and/or δI/I ref , and the consistency with known information. The calculated measures give rise to the figures of merit (FOM) of search match programs. It must always be remembered that two compounds of the same space group and similar cell parameters (eg. FCC metals) are going to have very similar diffraction patterns - any search/match technique usually arrives at a stage where there is a list of possibilities that must be decided between. The range search-match techniques span manual

  17. Comparison of laser diffraction and image analysis for measurement of Streptomyces coelicolor cell clumps and pellets

    DEFF Research Database (Denmark)

    Rønnest, Nanna Petersen; Stocks, Stuart M; Eliasson Lantz, Anna

    2012-01-01

    and pellets of Streptomyces coelicolor compare to image analysis. Samples, taken five times during fed-batch cultivation, were analyzed by image analysis and laser diffraction. The volume-weighted size distribution was calculated for each sample. Laser diffraction and image analysis yielded similar size...

  18. Classification using diffraction patterns for single-particle analysis

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Hongli; Zhang, Kaiming [Department of Biophysics, the Health Science Centre, Peking University, Beijing 100191 (China); Meng, Xing, E-mail: xmeng101@gmail.com [Wadsworth Centre, New York State Department of Health, Albany, New York 12201 (United States)

    2016-05-15

    An alternative method has been assessed; diffraction patterns derived from the single particle data set were used to perform the first round of classification in creating the initial averages for proteins data with symmetrical morphology. The test protein set was a collection of Caenorhabditis elegans small heat shock protein 17 obtained by Cryo EM, which has a tetrahedral (12-fold) symmetry. It is demonstrated that the initial classification on diffraction patterns is workable as well as the real-space classification that is based on the phase contrast. The test results show that the information from diffraction patterns has the enough details to make the initial model faithful. The potential advantage using the alternative method is twofold, the ability to handle the sets with poor signal/noise or/and that break the symmetry properties. - Highlights: • New classification method. • Create the accurate initial model. • Better in handling noisy data.

  19. Classification using diffraction patterns for single-particle analysis

    International Nuclear Information System (INIS)

    Hu, Hongli; Zhang, Kaiming; Meng, Xing

    2016-01-01

    An alternative method has been assessed; diffraction patterns derived from the single particle data set were used to perform the first round of classification in creating the initial averages for proteins data with symmetrical morphology. The test protein set was a collection of Caenorhabditis elegans small heat shock protein 17 obtained by Cryo EM, which has a tetrahedral (12-fold) symmetry. It is demonstrated that the initial classification on diffraction patterns is workable as well as the real-space classification that is based on the phase contrast. The test results show that the information from diffraction patterns has the enough details to make the initial model faithful. The potential advantage using the alternative method is twofold, the ability to handle the sets with poor signal/noise or/and that break the symmetry properties. - Highlights: • New classification method. • Create the accurate initial model. • Better in handling noisy data.

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

    International Nuclear Information System (INIS)

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

    2008-01-01

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

  1. Fast and accurate focusing analysis of large photon sieve using pinhole ring diffraction model.

    Science.gov (United States)

    Liu, Tao; Zhang, Xin; Wang, Lingjie; Wu, Yanxiong; Zhang, Jizhen; Qu, Hemeng

    2015-06-10

    In this paper, we developed a pinhole ring diffraction model for the focusing analysis of a large photon sieve. Instead of analyzing individual pinholes, we discuss the focusing of all of the pinholes in a single ring. An explicit equation for the diffracted field of individual pinhole ring has been proposed. We investigated the validity range of this generalized model and analytically describe the sufficient conditions for the validity of this pinhole ring diffraction model. A practical example and investigation reveals the high accuracy of the pinhole ring diffraction model. This simulation method could be used for fast and accurate focusing analysis of a large photon sieve.

  2. Crystallization and diffraction analysis of thioredoxin reductase from Streptomyces coelicolor

    International Nuclear Information System (INIS)

    Koháryová, Michaela; Brynda, Jiří; Řezáčová, Pavlína; Kollárová, Marta

    2011-01-01

    Thioredoxin reductase from S. coelicolor was crystallized and diffraction data were collected to 2.4 Å resolution. Thioredoxin reductases are homodimeric flavoenzymes that catalyze the transfer of electrons from NADPH to oxidized thioredoxin substrate. Bacterial thioredoxin reductases represent a promising target for the development of new antibiotics. Recombinant thioredoxin reductase TrxB from Streptomyces coelicolor was crystallized using the hanging-drop vapour-diffusion method. X-ray diffraction data were collected from cryocooled crystals to 2.4 Å resolution using a synchrotron-radiation source. The crystals belonged to the primitive monoclinic space group P2 1 , with unit-cell parameters a = 82.9, b = 60.6, c = 135.4 Å, α = γ = 90.0, β = 96.5°

  3. Electron diffraction, elemental and image analysis of nanocrystals

    Czech Academy of Sciences Publication Activity Database

    Šlouf, Miroslav; Pavlova, Ewa; Hromádková, Jiřina; Králová, Daniela; Tyrpekl, Václav

    2009-01-01

    Roč. 16, 2a (2009), s. 33-34 ISSN 1211-5894. [Struktura - Colloquium of Czech and Slovak Crystallographic Association. Hluboká nad Vltavou, 22.06.2009-25.06.2009] R&D Projects: GA AV ČR KAN200520704; GA ČR GA203/07/0717 Institutional research plan: CEZ:AV0Z40500505 Keywords : TEM * electron diffraction * nanocrystals Subject RIV: CD - Macromolecular Chemistry

  4. A global analysis of inclusive diffractive cross sections at HERA

    Energy Technology Data Exchange (ETDEWEB)

    Royon, C.; Schoeffel, L. [Service de Physique des Particules, CE-Saclay, F-91191 Gif-sur-Yvette Cedex (France); Sapeta, S. [M. Smoluchowski Institue of Physics Jagellonian University Reymonta 4, 30-059 Krakow (Poland); Peschanski, R. [Service de Physique Theorique, CE-Saclay, F-91191 Gif-sur-Yvette Cedex (France); Sauvan, E. [CPPM, IN2P3-CNRS et Universitie de la Mediterranee, F-13288 Marseille Cedex 09 (France)

    2006-10-15

    We describe the most recent data on the diffractive structure functions from the H1 and ZEUS Collaborations at HERA using four models. First, a Pomeron Structure Function (PSF) model, in which the Pomeron is considered as an object with parton distribution functions. Then, the Bartels Ellis Kowalski Wuesthoff (BEKW) approach is discussed, assuming the simplest perturbative description of the Pomeron using a two-gluon ladder. A third approach, the Bialas Peschanski (BP) model, based on the dipole formalism is then described. Finally, we discuss the Golec-Biernat-Wuesthoff (GBW) saturation model which takes into account saturation effects. The best description of all available measurements can be achieved with either the PSF based model or the BEKW approach. In particular, the BEKW prediction allows to include the highest {beta} measurements, which are dominated by higher twists effects and provide an efficient and compact parametrisation of the diffractive cross section. The two other models also give a good description of cross section measurements at small x with a small number of parameters. The comparison of all predictions allows us to identify interesting differences in the behaviour of the effective pomeron intercept and in the shape of the longitudinal component of the diffractive structure functions. In this last part, we present some features that can be discriminated by new experimental measurements, completing the HERA program. (authors)

  5. A global analysis of inclusive diffractive cross sections at HERA

    International Nuclear Information System (INIS)

    Royon, C.; Schoeffel, L.; Sapeta, S.; Peschanski, R.; Sauvan, E.

    2006-10-01

    We describe the most recent data on the diffractive structure functions from the H1 and ZEUS Collaborations at HERA using four models. First, a Pomeron Structure Function (PSF) model, in which the Pomeron is considered as an object with parton distribution functions. Then, the Bartels Ellis Kowalski Wuesthoff (BEKW) approach is discussed, assuming the simplest perturbative description of the Pomeron using a two-gluon ladder. A third approach, the Bialas Peschanski (BP) model, based on the dipole formalism is then described. Finally, we discuss the Golec-Biernat-Wuesthoff (GBW) saturation model which takes into account saturation effects. The best description of all available measurements can be achieved with either the PSF based model or the BEKW approach. In particular, the BEKW prediction allows to include the highest β measurements, which are dominated by higher twists effects and provide an efficient and compact parametrisation of the diffractive cross section. The two other models also give a good description of cross section measurements at small x with a small number of parameters. The comparison of all predictions allows us to identify interesting differences in the behaviour of the effective pomeron intercept and in the shape of the longitudinal component of the diffractive structure functions. In this last part, we present some features that can be discriminated by new experimental measurements, completing the HERA program. (authors)

  6. Quantum diffraction and interference of spatially correlated photon pairs and its Fourier-optical analysis

    International Nuclear Information System (INIS)

    Shimizu, Ryosuke; Edamatsu, Keiichi; Itoh, Tadashi

    2006-01-01

    We present one- and two-photon diffraction and interference experiments involving parametric down-converted photon pairs. By controlling the divergence of the pump beam in parametric down-conversion, the diffraction-interference pattern produced by an object changes from a quantum (perfectly correlated) case to a classical (uncorrelated) one. The observed diffraction and interference patterns are accurately reproduced by Fourier-optical analysis taking into account the quantum spatial correlation. We show that the relation between the spatial correlation and the object size plays a crucial role in the formation of both one- and two-photon diffraction-interference patterns

  7. 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

  8. X-ray diffraction analysis device with electronic photon counter

    International Nuclear Information System (INIS)

    Fillit, R.Y.; Bruyas, H.; Patay, F.

    1985-01-01

    The means provided to control the movements around the three axes are composed of step-by-step motors related to exits control logic which is connected to the calculation and monitored by a clock. The clock monitors also the calculator so as that the calculator controls, together with the programmable clock and control logic, the coordination of the whole rotation movements, along the three rotation axes, their velocity, their duration and the acquisition of the measured intensities of the diffracted X-ray beam [fr

  9. Diffraction analysis of materials under strong plastic deformation

    International Nuclear Information System (INIS)

    Pyzalla, A.

    2001-01-01

    The applicability of X-ray diffraction in analyses of the microstructure texture and intrinsic stresses of materials under strong plastic deformation is illustrated by examples and discussed. The experimental methods and findings are supplemented by numeric calculations. It is shown how the microstructure, texture and intrinsic stresses can thus be optimized already in the production process. Analyses of changes in materials during operation of a component provide information on loads and material response to loads which can then be used for optimization of the component, e.g. by constructional modifications or selective heat treatment [de

  10. Precise structural analysis of methane hydrate by neutron diffraction

    International Nuclear Information System (INIS)

    Igawa, Naoki; Hoshikawa, Akinori; Ishii, Yoshinobu

    2006-01-01

    Methane hydrate has attracted great interest as an energy resource to replace natural gas since this material is deposited in the seafloor and the deposits are estimated to exceed those of natural gas. Understanding the physical proprieties, such as the temperature dependence of the crystal structure, helps to specify the optimum environmental temperature and pressure during drilling, transport, and storage of methane hydrate. Clathrate hydrates consisted of encaging atomic and/or molecular species as a guest and host water formed by a hydrogen bonding. Although many studies on the clathrate hydrate including methane hydrate were reported, no detailed crystallographic property has yet been cleared. We focused on the motion of methane in the clathrate hydrate by the neutron diffraction. The crystal structure of the methane hydrate was analyzed by the applying the combination of the Rietveld refinement and the maximum entropy method (MEM) to neutron powder diffraction. Temperature dependence of the scattering-length density distribution maps revealed that the motion of methane molecules differs between the shapes of dodecahedron and tetrakaidecahedron. (author)

  11. 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

  12. Coherent diffraction microscopy at SPring-8: instrumentation, data acquisition and data analysis

    International Nuclear Information System (INIS)

    Xu, Rui; Salha, Sara; Raines, Kevin S.; Jiang, Huaidong; Chen, Chien-Chun; Takahashi, Yukio; Kohmura, Yoshiki; Nishino, Yoshinori; Song, Changyong; Ishikawa, Tetsuya; Miao, Jianwei

    2011-01-01

    An instrumentation and data analysis review of coherent diffraction microscopy at SPring-8 is given. This work will be of interest to those who want to apply coherent diffraction imaging to studies of materials science and biological samples. Since the first demonstration of coherent diffraction microscopy in 1999, this lensless imaging technique has been experimentally refined by continued developments. Here, instrumentation and experimental procedures for measuring oversampled diffraction patterns from non-crystalline specimens using an undulator beamline (BL29XUL) at SPring-8 are presented. In addition, detailed post-experimental data analysis is provided that yields high-quality image reconstructions. As the acquisition of high-quality diffraction patterns is at least as important as the phase-retrieval procedure to guarantee successful image reconstructions, this work will be of interest for those who want to apply this imaging technique to materials science and biological samples

  13. 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)

  14. Contemporary Use of Anomalous Diffraction in Biomolecular Structure Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Liu Q.; Hendrickson, W.

    2017-01-01

    The normal elastic X-ray scattering that depends only on electron density can be modulated by an ?anomalous? component due to resonance between X-rays and electronic orbitals. Anomalous scattering thereby precisely identifies atomic species, since orbitals distinguish atomic elements, which enables the multi- and single-wavelength anomalous diffraction (MAD and SAD) methods. SAD now predominates in de novo structure determination of biological macromolecules, and we focus here on the prevailing SAD method. We describe the anomalous phasing theory and the periodic table of phasing elements that are available for SAD experiments, differentiating between those readily accessible for at-resonance experiments and those that can be effective away from an edge. We describe procedures for present-day SAD phasing experiments and we discuss optimization of anomalous signals for challenging applications. We also describe methods for using anomalous signals as molecular markers for tracing and element identification. Emerging developments and perspectives are discussed in brief.

  15. Measurement and QCD analysis of diffractive jet cross sections in deep inelastic scattering at HERA

    Energy Technology Data Exchange (ETDEWEB)

    Mozer, M.U.

    2006-07-24

    Differential cross sections for the production of two jets in diffractive deep inelastic scattering (DIS) at HERA are presented. The process studied is of the type ep{yields}eXY, where the central hadronic system X contains at least two jets and is separated from the system Y by a gap in rapidity. The forward system Y consists of an elastically scattered proton or a low mass dissociation system. The data were taken with the H1 detector during the years of 1999 and 2000 and correspond to an integrated luminosity of 51.5 pb{sup -1}. The measured cross sections are compared to fixed order NLO QCD predictions, that use diffractive parton densities which have previously been determined by a NLO QCD analysis of inclusive diffractive DIS at H1. The prediction and the data show significant differences. However, the dijet cross section is dominated by the diffractive gluon density, which can be extracted by the above mentioned analysis only with considerable uncertainty. Hence a combined QCD analysis of the previously published inclusive diffractive data and the dijet data is performed. This combined fit analysis allows the determination of diffractive quark and gluon densities with comparable precision. The common description of inclusive diffractive data and the dijet data confirms QCD factorization. (orig.)

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

    Data.gov (United States)

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

  17. X-Ray Diffraction and Fluorescence Instrument for Mineralogical Analysis at the Lunar Surface, Phase I

    Data.gov (United States)

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

  18. Quantitative method of X-ray diffraction phase analysis of building materials

    International Nuclear Information System (INIS)

    Czuba, J.; Dziedzic, A.

    1978-01-01

    Quantitative method of X-ray diffraction phase analysis of building materials, with use of internal standard, has been presented. The errors committed by determining the content of particular phases have been also given. (author)

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

    International Nuclear Information System (INIS)

    Salih, Suad Z.Elabdeen

    1997-03-01

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

  20. Quantitative evaluation of fluctuation error in X-ray diffraction profiles with fractal analysis

    International Nuclear Information System (INIS)

    Kurose, Masashi; Hirose, Yukio; Sasaki, Toshihiko; Yoshioka, Yasuo.

    1995-01-01

    A method of the fractal analysis was applied to the diffraction profiles for its quantitative evaluation. The fractal dimension was analyzed according to both Box counting method and FFT method. The relationship between the fractal dimension and the measurement criteria in X-ray diffraction analysis was discussed with diffraction data obtained under various conditions of the measurement. It was concluded that the fractal analysis is effective for the quantitative evaluation of diffraction data. Box counting method is suitable for evaluation of a whole profile, and FFT method is for that of a fundamental profile. The range of desirable condition of measurement is 1.0≤D≤1.2, where D is a fractal dimension. The appropriate range of measurement becomes 0.01≤Sw/HVB≤0.03, where Sw is the step width and the HVB is the half-value breadth. Stresses with higher precision were obtained from measurements under this new criteria. (author)

  1. COMPARING PARTICLE SIZE DISTRIBUTION ANALYSIS BY SEDIMENTATION AND LASER DIFFRACTION METHOD

    Directory of Open Access Journals (Sweden)

    Vito Ferro

    2009-06-01

    Full Text Available In this paper a brief review of the laser diffraction method is firstly carried out. Then, for 30 soil samples having a different texture classification sampled in Sicilian basin, a comparison between the two techniques is developed. The analysis demonstrated that the sand content measured by Sieve-Hydrometer method can be assumed equal to the one determinated by laser diffraction technique while an overestimation of the clay fraction measured by Sieve-Hydrometer method respect to laser diffraction technique was obtained. Finally a set of equations useful to refer LD measurements to SH method was proposed.

  2. Crystallization and preliminary X-ray diffraction analysis of West Nile virus

    International Nuclear Information System (INIS)

    Kaufmann, Bärbel; Plevka, Pavel; Kuhn, Richard J.; Rossmann, Michael G.

    2010-01-01

    Crystals of infectious West Nile virus were obtained and diffracted at best to about 25 Å resolution. Preliminary analysis of the diffraction pattern suggested tight hexagonal packing of the intact virus. West Nile virus, a human pathogen, is closely related to other medically important flaviviruses of global impact such as dengue virus. The infectious virus was purified from cell culture using polyethylene glycol (PEG) precipitation and density-gradient centrifugation. Thin amorphously shaped crystals of the lipid-enveloped virus were grown in quartz capillaries equilibrated by vapor diffusion. Crystal diffraction extended at best to a resolution of about 25 Å using synchrotron radiation. A preliminary analysis of the diffraction images indicated that the crystals had unit-cell parameters a ≃ b ≃ 480 Å, γ = 120°, suggesting a tight hexagonal packing of one virus particle per unit cell

  3. 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

  4. Diffraction efficiency and noise analysis of hidden image holograms

    DEFF Research Database (Denmark)

    Tamulevičius, Sigitas; Andrulevičius, Mindaugas; Puodžiukynas, Linas

    2017-01-01

    recorded in a photoresist layer spin-coated on glass substrates applying laser interference lithography technique. Both analogue and digital analysis approaches showed the similar results thus confirming the appropriateness of the used analysis methods. It was found that holograms recorded at higher laser...

  5. COMPARING PARTICLE SIZE DISTRIBUTION ANALYSIS BY SEDIMENTATION AND LASER DIFFRACTION METHOD

    OpenAIRE

    Vito Ferro; Stefano Mirabile

    2009-01-01

    In this paper a brief review of the laser diffraction method is firstly carried out. Then, for 30 soil samples having a different texture classification sampled in Sicilian basin, a comparison between the two techniques is developed. The analysis demonstrated that the sand content measured by Sieve-Hydrometer method can be assumed equal to the one determinated by laser diffraction technique while an overestimation of the clay fraction measured by Sieve-Hydrometer method respect to laser diffr...

  6. X-ray diffraction analysis with diffractometer DRON-1

    International Nuclear Information System (INIS)

    Bochenin, V.I.

    1978-01-01

    Rapid methods of phase quantitative analysis of wolframite (FeMn)WO 4 and molybdenite MoS 2 in industrial materials using DRON-1 diffractometer are suggested. Diffractometer with spectrometric attachment was used for determination of (FeMn)WO 4 in industrial raw materials. Results of the above analysis have been compared with the data of chemical analysis, their good agreement has been shown. Time of wolframite determination in one sample is 8-10 min. Method of standard background with respect to absorption properties of medium has been developed for MoS 2 rapid determination in enriched molybdenum ore. Time of molybdenite determination in one sample is 3-4min., error is 4 % rel. in MoS 2 concentration range from 15.4 to 36.7 %

  7. In situ diffraction profile analysis during tensile deformation motivated by molecular dynamics

    International Nuclear Information System (INIS)

    Van Swygenhoven, H.; Budrovic, Z.; Derlet, P.M.; Froseth, A.G.; Van Petegem, S.

    2005-01-01

    Molecular dynamics simulations can provide insight into the slip mechanism at the atomic scale and suggest that in nanocrystalline metals dislocations are nucleated and absorbed by the grain boundaries. However, this technique is limited by very short simulation times. Using suggestions from molecular dynamics, we have developed a new in situ X-ray diffraction technique wherein the profile analysis of several Bragg diffraction peaks during tensile deformation is possible. Combining experiment and careful structural analysis the results confirm the suggestions from atomistic simulations

  8. Device for high-temperature X-ray diffraction analysis. Ustrojstvo dlya vysokotemperaturnogo rentgenostrukturnogo analiza

    Energy Technology Data Exchange (ETDEWEB)

    Epifanov, V G; Zavilinskij, A V; Pet' kov, V V; Polenur, A V

    1975-01-07

    Device for high-temperature X-ray diffraction analysis, containing a vacuum chamber with a window for X-ray transit, in which sample- and standard-holders, heater, thermal shields and means for standard and sample temperature measurement are located, is proposed. In order to increase the working temperature level and the structural change detection accuracy the heater is located between the sample- and standard-holders. The standard-holder is linked with the mechanism of control of its position in relation to the heater. The device is intended for investigating phase transformations by differential thermal analysis method with the simultaneous diffraction pattern detection using X-ray diffractometry method.

  9. Crystallization and preliminary X-ray diffraction analysis of rat autotaxin

    International Nuclear Information System (INIS)

    Day, Jacqueline E.; Hall, Troii; Pegg, Lyle E.; Benson, Timothy E.; Hausmann, Jens; Kamtekar, Satwik

    2010-01-01

    Autotaxin (ATX), a pyrophosphatase/phosphodiesterase enzyme, is a promising drug target for many indications and is only distantly related to enzymes of previously determined structure. Here, the cloning, expression, purification, crystallization and preliminary diffraction analysis of ATX are reported. Rat autotaxin has been cloned, expressed, purified to homogeneity and crystallized via hanging-drop vapour diffusion using PEG 3350 as precipitant and ammonium iodide and sodium thiocyanate as salts. The crystals diffracted to a maximum resolution of 2.05 Å and belonged to space group P1, with unit-cell parameters a = 53.8, b = 63.3, c = 70.5 Å, α = 98.8, β = 106.2, γ = 99.8°. Preliminary X-ray diffraction analysis indicated the presence of one molecule per asymmetric unit, with a solvent content of 47%

  10. Regge analysis of diffractive and leading baryon structure functions from deep inelastic scattering

    International Nuclear Information System (INIS)

    Batista, M.; Covolan, R.J.M.; Montanha, J.

    2002-01-01

    In this paper we present a combined analysis of the H1 data on leading baryon and diffractive structure functions from DIS, which are handled as two components of the same semi-inclusive process. The available structure function data are analyzed in a series of fits in which three main exchanges are taken into account: the Pomeron, Reggeon, and pion. For each of these contributions, Regge factorization of the correspondent structure function is assumed. By this procedure, we extract information about the interface between the diffractive, Pomeron-dominated, region and the leading proton spectrum, which is mostly ruled by secondary exchanges. One of the main results is that the relative Reggeon contribution to the semi-inclusive structure function is much smaller than the one obtained from an analysis of the diffractive structure function alone

  11. Structure analysis of liquids and disordered materials using pulsed neutron diffraction and total scattering

    International Nuclear Information System (INIS)

    Suzuya, Kentaro

    2011-01-01

    Neutron diffraction·total scattering at pulsed neutron source is a powerful method to analyze the complex structure of disordered materials: liquids, glasses, amorphous materials and disordered crystals. The basic idea of the structure of disordered materials, the fundamental diffraction theory for disordered materials, and structure analysis of disordered materials using pulsed neutron diffraction·total scattering technique (TOF method) are described in detail. In addition, the precise information of the world highest class J-PARC MLF spallation neutron source and typical J-PARC neutron total scattering instrument NOVA are also given. Recent structural modelling methods of disordered materials such like reverse Monte Carlo (RMC) simulation method is briefly described using an example of the analysis of a typical disordered material silica glass. (author)

  12. Quantitative phase analysis of uranium carbide from x-ray diffraction data using the Rietveld method

    International Nuclear Information System (INIS)

    Singh Mudher, K.D.; Krishnan, K.

    2003-01-01

    Quantitative phase analysis of a uranium carbide sample was carried out from the x-ray diffraction data by Rietveld profile fitting method. The method does not require the addition of any reference material. The percentage of UC, UC 2 and UO 2 phases in the sample were determined. (author)

  13. Incident spectrum determination for time-of-flight neutron powder diffraction data analysis

    International Nuclear Information System (INIS)

    Hodges, J. P.

    1998-01-01

    Accurate characterization of the incident neutron spectrum is an important requirement for precise Rietveld analysis of time-of-flight powder neutron diffraction data. Without an accurate incident spectrum the calculated model for the measured relative intensities of individual Bragg reflections will possess systematic errors. We describe a method for obtaining an accurate numerical incident spectrum using data from a transmitted beam monitor

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

    Indian Academy of Sciences (India)

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

  15. Role of diffraction and electron analysis in the fast reactor programme

    Energy Technology Data Exchange (ETDEWEB)

    Ferguson, I. F. [ed.

    1975-09-15

    After first discussing irradiation damage, the whole range of new methods of probe analysis were reviewed with a special reference to the study of surfaces. Further papers discussed scanning auger microscopy and the nuclear microprobe. Current diffraction studies were then described on uranium dioxide and the neutron poisons: boron carbide and europia. Finally, new techniques were covered with special reference to the scanning electron microscope and the application of the Harwell 6000 series electronics to x-ray diffraction. Separate records were prepared for each paper covered.

  16. ZDS - a computer program for analysis of X-ray powder diffraction patterns

    International Nuclear Information System (INIS)

    Ondrus, P.

    1993-01-01

    The ZDS system creates an integrated environment of procedures for complete and precise analysis of raw powder diffraction patterns. The basis of the ZDS system is a graphic control centre for easy and user-friendly application of all included procedures. It offers a number of application procedures without an interaction with any data base. The program operates either in an automatic or manual mode. The manual mode makes possible specialized applications. The input and output of the data are compatible with Philips and Siemens powder diffraction software. The ZDS system runs with Intel 80286 or 80386-based PC computers with or without math-coprocesor. (orig.)

  17. The Gaussian beam mode analysis of classical phase aberrations in diffraction-limited optical systems

    Science.gov (United States)

    Trappe, Neil; Murphy, J. Anthony; Withington, Stafford

    2003-07-01

    Gaussian beam mode analysis (GBMA) offers a more intuitive physical insight into how light beams evolve as they propagate than the conventional Fresnel diffraction integral approach. In this paper we illustrate that GBMA is a computationally efficient, alternative technique for tracing the evolution of a diffracting coherent beam. In previous papers we demonstrated the straightforward application of GBMA to the computation of the classical diffraction patterns associated with a range of standard apertures. In this paper we show how the GBMA technique can be expanded to investigate the effects of aberrations in the presence of diffraction by introducing the appropriate phase error term into the propagating quasi-optical beam. We compare our technique to the standard diffraction integral calculation for coma, astigmatism and spherical aberration, taking—for comparison—examples from the classic text 'Principles of Optics' by Born and Wolf. We show the advantages of GBMA for allowing the defocusing of an aberrated image to be evaluated quickly, which is particularly important and useful for probing the consequences of astigmatism and spherical aberration.

  18. The Gaussian beam mode analysis of classical phase aberrations in diffraction-limited optical systems

    International Nuclear Information System (INIS)

    Trappe, Neil; Murphy, J Anthony; Withington, Stafford

    2003-01-01

    Gaussian beam mode analysis (GBMA) offers a more intuitive physical insight into how light beams evolve as they propagate than the conventional Fresnel diffraction integral approach. In this paper we illustrate that GBMA is a computationally efficient, alternative technique for tracing the evolution of a diffracting coherent beam. In previous papers we demonstrated the straightforward application of GBMA to the computation of the classical diffraction patterns associated with a range of standard apertures. In this paper we show how the GBMA technique can be expanded to investigate the effects of aberrations in the presence of diffraction by introducing the appropriate phase error term into the propagating quasi-optical beam. We compare our technique to the standard diffraction integral calculation for coma, astigmatism and spherical aberration, taking - for comparison - examples from the classic text 'Principles of Optics' by Born and Wolf. We show the advantages of GBMA for allowing the defocusing of an aberrated image to be evaluated quickly, which is particularly important and useful for probing the consequences of astigmatism and spherical aberration

  19. Crystallization and preliminary X-ray diffraction analysis of mevalonate kinase from Methanosarcina mazei

    International Nuclear Information System (INIS)

    Zhuang, Ningning; Seo, Kyung Hye; Chen, Cong; Zhou, Jia; Kim, Seon Won; Lee, Kon Ho

    2012-01-01

    Recombinant mevalonate kinase from M. mazei has been crystallized. Diffraction data were collected to 2.08 Å resolution. Mevalonate kinase (MVK), which plays an important role in catalysing the biosynthesis of isoprenoid compounds derived from the mevalonate pathway, transforms mevalonate to 5-phosphomevalonate using ATP as a cofactor. Mevalonate kinase from Methanosarcina mazei (MmMVK) was expressed in Escherichia coli, purified and crystallized for structural analysis. Diffraction-quality crystals of MmMVK were obtained by the vapour-diffusion method using 0.32 M MgCl 2 , 0.08 M bis-tris pH 5.5, 16%(w/v) PEG 3350. The crystals belonged to space group P2 1 2 1 2, with unit-cell parameters a = 97.11, b = 135.92, c = 46.03 Å. Diffraction data were collected to 2.08 Å resolution

  20. Crystallization and preliminary X-ray diffraction analysis of the middle domain of Paip1

    International Nuclear Information System (INIS)

    Kanaan, Ahmad Seif; Frank, Filipp; Maedler-Kron, Chelsea; Verma, Karan; Sonenberg, Nahum; Nagar, Bhushan

    2009-01-01

    The crystallization of the putative MIF4G domain of Paip1 is described. The crystals belonged to the monoclinic space group P2 1 and diffracted X-rays to beyond 2.2 Å resolution. The poly(A)-binding protein (PABP) simultaneously interacts with the poly(A) tail of mRNAs and the scaffolding protein eIF4G to mediate mRNA circularization, resulting in stimulation of protein translation. PABP is regulated by the PABP-interacting protein Paip1. Paip1 is thought to act as a translational activator in 5′ cap-dependent translation by interacting with PABP and the initiation factors eIF4A and eIF3. Here, the crystallization and preliminary diffraction analysis of the middle domain of Paip1 (Paip1M), which produces crystals that diffract to a resolution of 2.2 Å, are presented

  1. Synchrotron X-ray diffraction analysis for quantitative defect evaluation in GaP/Si nanolayers

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen Thanh, T.; Robert, C. [Université Européenne de Bretagne, INSA, FOTON, UMR 6082, F-35708 RENNES (France); Létoublon, A., E-mail: Antoine.letoublon@insa-rennes.fr [Université Européenne de Bretagne, INSA, FOTON, UMR 6082, F-35708 RENNES (France); Cornet, C. [Université Européenne de Bretagne, INSA, FOTON, UMR 6082, F-35708 RENNES (France); Quinci, T. [Université Européenne de Bretagne, INSA, FOTON, UMR 6082, F-35708 RENNES (France); CEA LCP, INES, 50 av. du Lac Léman, Savoie Technolac, 73375 Le Bourget du Lac (France); Giudicelli, E.; Almosni, S. [Université Européenne de Bretagne, INSA, FOTON, UMR 6082, F-35708 RENNES (France); Boudet, N. [CRG-D2AM, ESRF and Inst. Néel, CNRS-UJF, 25 Av des Martyrs, 38042 Grenoble (France); Ponchet, A. [CEMES, CNRS, Université de Toulouse, 29 rue J. Marvig BP 94347, 31055 Toulouse Cedex 4 (France); Kuyyalil, J. [Université Européenne de Bretagne, INSA, FOTON, UMR 6082, F-35708 RENNES (France); Danila, M. [National Institute for Research and Development in Microtechnologies (IMT), 126A Erou Iancu Nicolae Street, 077190, Bucharest (Romania); Durand, O.; Bertru, N.; Le Corre, A. [Université Européenne de Bretagne, INSA, FOTON, UMR 6082, F-35708 RENNES (France)

    2013-08-31

    In the context of III–V monolithic integration on silicon, synchrotron X-ray diffraction has been employed in this study using a bi-dimensional large area hybrid pixel detector (XPAD third generation) to characterize defects in the GaP layers. Despite a very coherent interface (low plastic relaxation) of GaP/Si, 2 types of defect are detected. Micro-twins contributions are evidenced and quantitatively evaluated from additional reflections analysis. Antiphase domains are evidenced using the Williamson-Hall-like plot method applied to transverse scans extracted directly from single XPAD images taken on specular GaP reflections. - Highlights: ► Antiphase domain evidence and characterization in GaP/Si using X-ray diffraction ► Microtwin evidence and characterization ► Synchrotron diffraction ► Large area X-ray hybrid pixel detector.

  2. Advances in X-ray powder diffraction profile analysis and its application in ceramic material studies

    International Nuclear Information System (INIS)

    Zhang, Y.

    1988-01-01

    This dissertation is concerned with the following major aspects: (1) the development of necessary computer codes to carry out X-ray powder diffraction profile analysis (XPDPA) calculations; (2) the establishment of a general reference material (GRM) which greatly extends the application of XPDPA and the study of the application of the GRM in profile analysis; (3) the determination of the coherent diffracting domain size and the lattice residual microstrain for some shock-modified and jet-milled materials. A computer code for diffraction profile refinement, XRAYL, fits a diffraction profile with any one of five mathematical functions, either as symmetric or asymmetric (split mode) forms. The resulting patterns meet the requirements for successful profile analysis of microstrain and crystallite size. Powder diffraction profile analysis requires an instrument calibration standard to correct data for instrumental profiles due to the system optics. A general reference material, LaB 6 , has been established. The pattern of this LaB 6 powder can be used to generate a reference pattern for any other substance. Through three applications, it has been shown that this LaB 6 sample can be used to remove the instrumental broadenings and gives reasonable size and strain estimates in the profile analysis of other materials. Many previous studies have shown that the solid state reactivity and physical properties of some ceramic materials can be substantially enhanced. XPDPA techniques have been used to study the plastic deformation and the reduction of crystallite size for eight shock-modified ceramic materials. The size and strain values of these materials are correlated with shock parameters

  3. Quantitative analysis of phases by x-ray diffraction and thermogravimetry in Cuban phosphorite ores

    International Nuclear Information System (INIS)

    Casanova Gomez, Abdel; Martinez Montalvo, Asor; Cilano Campos, Guillermo; Arostegui Aguirre, Miladys; Ferreiro Fernandez, Adalyz; Alonso Perez, Jose A.

    2016-01-01

    Phases analysis is performed by instrumental techniques X - ray diffraction and Thermal Analysis in two groups of samples of Cuban minerals carriers'phosphorus, candidates to reference materials. To this end, the variant of structural refinement of the diffraction pattern in the form of adjustment profile is applied, using the Full prof program of Juan Rodriguez-Carvajal. This analysis is the first step to develop the standard specification of these resources and classify them as phosphate rock and / or phospharite from their mass content. The statistical evaluation of the uncertainty of the quantitative analysis (standard deviation) was carried out in ten replicate samples of phosphate rock and eight of phosphate from the field Trinidad de Guedes. The qualitative phase analysis reflected the following phase composition: carbonate fluoroapatite (CFA), Calcite, Quartz and Halloysite (present only in the clayey granular phosphorite ore; FGA). By the method of setting pattern powder diffraction profile, the quantitative phase composition is reported in the sample FGA: 87 (2) % of CFA, 4 (1) % of Calcite, 1% Quartz, and 8 (3) % Halloysite. For granular limestone ore (FGC), the following contents were obtained: 87 (3) % Calcite, 8 (3) % of CFA and 5 (1) % Quartz: The obtained values are corroborated by Thermogravimetric Analysis (TG) through the calculation of the mass content of the thermally active phases (Calcite and CFA) in the range (27-10000 0 C), confirming the validity of the results of XRD. (Author)

  4. Liquid contrabands classification based on energy dispersive X-ray diffraction and hybrid discriminant analysis

    International Nuclear Information System (INIS)

    YangDai, Tianyi; Zhang, Li

    2016-01-01

    Energy dispersive X-ray diffraction (EDXRD) combined with hybrid discriminant analysis (HDA) has been utilized for classifying the liquid materials for the first time. The XRD spectra of 37 kinds of liquid contrabands and daily supplies were obtained using an EDXRD test bed facility. The unique spectra of different samples reveal XRD's capability to distinguish liquid contrabands from daily supplies. In order to create a system to detect liquid contrabands, the diffraction spectra were subjected to HDA which is the combination of principal components analysis (PCA) and linear discriminant analysis (LDA). Experiments based on the leave-one-out method demonstrate that HDA is a practical method with higher classification accuracy and lower noise sensitivity than the other methods in this application. The study shows the great capability and potential of the combination of XRD and HDA for liquid contrabands classification.

  5. Liquid contrabands classification based on energy dispersive X-ray diffraction and hybrid discriminant analysis

    Energy Technology Data Exchange (ETDEWEB)

    YangDai, Tianyi [Department of Engineering Physics, Tsinghua University, Beijing 100084 (China); Key Laboratory of Particle & Radiation Imaging (Tsinghua University), Ministry of Education (China); Zhang, Li, E-mail: zhangli@nuctech.com [Department of Engineering Physics, Tsinghua University, Beijing 100084 (China); Key Laboratory of Particle & Radiation Imaging (Tsinghua University), Ministry of Education (China)

    2016-02-01

    Energy dispersive X-ray diffraction (EDXRD) combined with hybrid discriminant analysis (HDA) has been utilized for classifying the liquid materials for the first time. The XRD spectra of 37 kinds of liquid contrabands and daily supplies were obtained using an EDXRD test bed facility. The unique spectra of different samples reveal XRD's capability to distinguish liquid contrabands from daily supplies. In order to create a system to detect liquid contrabands, the diffraction spectra were subjected to HDA which is the combination of principal components analysis (PCA) and linear discriminant analysis (LDA). Experiments based on the leave-one-out method demonstrate that HDA is a practical method with higher classification accuracy and lower noise sensitivity than the other methods in this application. The study shows the great capability and potential of the combination of XRD and HDA for liquid contrabands classification.

  6. Liquid contrabands classification based on energy dispersive X-ray diffraction and hybrid discriminant analysis

    Science.gov (United States)

    YangDai, Tianyi; Zhang, Li

    2016-02-01

    Energy dispersive X-ray diffraction (EDXRD) combined with hybrid discriminant analysis (HDA) has been utilized for classifying the liquid materials for the first time. The XRD spectra of 37 kinds of liquid contrabands and daily supplies were obtained using an EDXRD test bed facility. The unique spectra of different samples reveal XRD's capability to distinguish liquid contrabands from daily supplies. In order to create a system to detect liquid contrabands, the diffraction spectra were subjected to HDA which is the combination of principal components analysis (PCA) and linear discriminant analysis (LDA). Experiments based on the leave-one-out method demonstrate that HDA is a practical method with higher classification accuracy and lower noise sensitivity than the other methods in this application. The study shows the great capability and potential of the combination of XRD and HDA for liquid contrabands classification.

  7. Measurement and QCD analysis of the diffractive deep-inelastic scattering cross section at HERA

    International Nuclear Information System (INIS)

    Aktas, A.; Andreev, V.; Anthonis, T.

    2006-05-01

    A detailed analysis is presented of the diffractive deep-inelastic scattering process ep→eXY, where Y is a proton or a low mass proton excitation carrying a fraction 1-x P >0.95 of the incident proton longitudinal momentum and the squared four-momentum transfer at the proton vertex satisfies t 2 . Using data taken by the H1 experiment, the cross section is measured for photon virtualities in the range 3.5 ≤Q 2 ≤1600 GeV 2 , triple differentially in x P , Q 2 and β=x/x P , where x is the Bjorken scaling variable. At low x P , the data are consistent with a factorisable x P dependence, which can be described by the exchange of an effective pomeron trajectory with intercept α P (0)=1.118 ±0.008(exp.) +0.029 -0.010 (model). Diffractive parton distribution functions and their uncertainties are determined from a next-to-leading order DGLAP QCD analysis of the Q 2 and β dependences of the cross section. The resulting gluon distribution carries an integrated fraction of around 70% of the exchanged momentum in the Q 2 range studied. Total and differential cross sections are also measured for the diffractive charged current process e + p → anti ν e XY and are found to be well described by predictions based on the diffractive parton distributions. The ratio of the diffractive to the inclusive neutral current ep cross sections is studied. Over most of the kinematic range, this ratio shows no significant dependence on Q 2 at fixed x P and x or on x at fixed Q 2 and β. (Orig.)

  8. Measurement and QCD analysis of the diffractive deep-inelastic scattering cross section at HERA

    Science.gov (United States)

    Aktas, A.; Andreev, V.; Anthonis, T.; Antunovic, B.; Aplin, S.; Asmone, A.; Astvatsatourov, A.; Babaev, A.; Backovic, S.; Baghdasaryan, A.; Baranov, P.; Barrelet, E.; Bartel, W.; Baudrand, S.; Baumgartner, S.; Beckingham, M.; Behnke, O.; Behrendt, O.; Belousov, A.; Berger, N.; Bizot, J. C.; Boenig, M.-O.; Boudry, V.; Bracinik, J.; Brandt, G.; Brisson, V.; Bruncko, D.; Büsser, F. W.; Bunyatyan, A.; Buschhorn, G.; Bystritskaya, L.; Campbell, A. J.; Cassol-Brunner, F.; Cerny, K.; Cerny, V.; Chekelian, V.; Contreras, J. G.; Coughlan, J. A.; Coppens, Y. R.; Cox, B. E.; Cozzika, G.; Cvach, J.; Dainton, J. B.; Dau, W. D.; Daum, K.; de Boer, Y.; Delcourt, B.; Del Degan, M.; de Roeck, A.; de Wolf, E. A.; Diaconu, C.; Dodonov, V.; Dubak, A.; Eckerlin, G.; Efremenko, V.; Egli, S.; Eichler, R.; Eisele, F.; Eliseev, A.; Elsen, E.; Essenov, S.; Falkewicz, A.; Faulkner, P. J. W.; Favart, L.; Fedotov, A.; Felst, R.; Feltesse, J.; Ferencei, J.; Finke, L.; Fleischer, M.; Flucke, G.; Fomenko, A.; Franke, G.; Frisson, T.; Gabathuler, E.; Garutti, E.; Gayler, J.; Gerlich, C.; Ghazaryan, S.; Ginzburgskaya, S.; Glazov, A.; Glushkov, I.; Goerlich, L.; Goettlich, M.; Gogitidze, N.; Gorbounov, S.; Grab, C.; Greenshaw, T.; Gregori, M.; Grell, B. R.; Grindhammer, G.; Gwilliam, C.; Haidt, D.; Hansson, M.; Heinzelmann, G.; Henderson, R. C. W.; Henschel, H.; Herrera, G.; Hildebrandt, M.; Hiller, K. H.; Hoffmann, D.; Horisberger, R.; Hovhannisyan, A.; Hreus, T.; Hussain, S.; Ibbotson, M.; Ismail, M.; Jacquet, M.; Janssen, X.; Jemanov, V.; Jönsson, L.; Johnson, C. L.; Johnson, D. P.; Jung, A. W.; Jung, H.; Kapichine, M.; Katzy, J.; Kenyon, I. R.; Kiesling, C.; Klein, M.; Kleinwort, C.; Klimkovich, T.; Kluge, T.; Knies, G.; Knutsson, A.; Korbel, V.; Kostka, P.; Krastev, K.; Kretzschmar, J.; Kropivnitskaya, A.; Krüger, K.; Landon, M. P. J.; Lange, W.; Laštovička-Medin, G.; Laycock, P.; Lebedev, A.; Leibenguth, G.; Lendermann, V.; Levonian, S.; Lindfeld, L.; Lipka, K.; Liptaj, A.; List, B.; List, J.; Lobodzinska, E.; Loktionova, N.; Lopez-Fernandez, R.; Lubimov, V.; Lucaci-Timoce, A.-I.; Lueders, H.; Lux, T.; Lytkin, L.; Makankine, A.; Malden, N.; Malinovski, E.; Marage, P.; Marshall, R.; Marti, L.; Martisikova, M.; Martyn, H.-U.; Maxfield, S. J.; Mehta, A.; Meier, K.; Meyer, A. B.; Meyer, H.; Meyer, J.; Michels, V.; Mikocki, S.; Milcewicz-Mika, I.; Milstead, D.; Mladenov, D.; Mohamed, A.; Moreau, F.; Morozov, A.; Morris, J. V.; Mozer, M. U.; Müller, K.; Murín, P.; Nankov, K.; Naroska, B.; Naumann, T.; Newman, P. R.; Niebuhr, C.; Nikiforov, A.; Nowak, G.; Nowak, K.; Nozicka, M.; Oganezov, R.; Olivier, B.; Olsson, J. E.; Osman, S.; Ozerov, D.; Palichik, V.; Panagoulias, I.; Papadopoulou, T.; Pascaud, C.; Patel, G. D.; Peng, H.; Perez, E.; Perez-Astudillo, D.; Perieanu, A.; Petrukhin, A.; Pitzl, D.; Plačakytė, R.; Portheault, B.; Povh, B.; Prideaux, P.; Rahmat, A. J.; Raicevic, N.; Reimer, P.; Rimmer, A.; Risler, C.; Rizvi, E.; Robmann, P.; Roland, B.; Roosen, R.; Rostovtsev, A.; Rurikova, Z.; Rusakov, S.; Salvaire, F.; Sankey, D. P. C.; Sauter, M.; Sauvan, E.; Schilling, F.-P.; Schmidt, S.; Schmitt, S.; Schmitz, C.; Schoeffel, L.; Schöning, A.; Schultz-Coulon, H.-C.; Sefkow, F.; Shaw-West, R. N.; Sheviakov, I.; Shtarkov, L. N.; Sloan, T.; Smirnov, P.; Soloviev, Y.; South, D.; Spaskov, V.; Specka, A.; Steder, M.; Stella, B.; Stiewe, J.; Stoilov, A.; Straumann, U.; Sunar, D.; Tchoulakov, V.; Thompson, G.; Thompson, P. D.; Toll, T.; Tomasz, F.; Traynor, D.; Trinh, T. N.; Truöl, P.; Tsakov, I.; Tsipolitis, G.; Tsurin, I.; Turnau, J.; Tzamariudaki, E.; Urban, K.; Urban, M.; Usik, A.; Utkin, D.; Valkárová, A.; Vallée, C.; van Mechelen, P.; Vargas Trevino, A.; Vazdik, Y.; Veelken, C.; Vinokurova, S.; Volchinski, V.; Wacker, K.; Weber, G.; Weber, R.; Wegener, D.; Werner, C.; Wessels, M.; Wessling, B.; Wissing, C.; Wolf, R.; Wünsch, E.; Xella, S.; Yan, W.; Yeganov, V.; Žáček, J.; Zálešák, J.; Zhang, Z.; Zhelezov, A.; Zhokin, A.; Zhu, Y. C.; Zimmermann, J.; Zimmermann, T.; Zohrabyan, H.; Zomer, F.

    2006-12-01

    A detailed analysis is presented of the diffractive deep-inelastic scattering process ep→eXY, where Y is a proton or a low mass proton excitation carrying a fraction 1-xIP>0.95 of the incident proton longitudinal momentum and the squared four-momentum transfer at the proton vertex satisfies |t|<1 GeV2. Using data taken by the H1 experiment, the cross section is measured for photon virtualities in the range 3.5≤Q2≤1600 GeV2, triple differentially in xIP, Q2 and β=x/xIP, where x is the Bjorken scaling variable. At low xIP, the data are consistent with a factorisable xIP dependence, which can be described by the exchange of an effective pomeron trajectory with intercept αIP(0)=1.118±0.008(exp.)+0.029 -0.010(model). Diffractive parton distribution functions and their uncertainties are determined from a next-to-leading order DGLAP QCD analysis of the Q2 and β dependences of the cross section. The resulting gluon distribution carries an integrated fraction of around 70% of the exchanged momentum in the Q2 range studied. Total and differential cross sections are also measured for the diffractive charged current process e+p→ν¯eXY and are found to be well described by predictions based on the diffractive parton distributions. The ratio of the diffractive to the inclusive neutral current ep cross sections is studied. Over most of the kinematic range, this ratio shows no significant dependence on Q2 at fixed xIP and x or on x at fixed Q2 and β.

  9. Circular Hough transform diffraction analysis: A software tool for automated measurement of selected area electron diffraction patterns within Digital MicrographTM

    International Nuclear Information System (INIS)

    Mitchell, D.R.G.

    2008-01-01

    A software tool (script and plugin) for computing circular Hough transforms (CHT) in Digital Micrograph TM has been developed, for the purpose of automated analysis of selected area electron diffraction patterns (SADPs) of polycrystalline materials. The CHT enables the diffraction pattern centre to be determined with sub-pixel accuracy, regardless of the exposure condition of the transmitted beam or if a beam stop is present. Radii of the diffraction rings can also be accurately measured with sub-pixel precision. If the pattern is calibrated against a known camera length, then d-spacings with an accuracy of better than 1% can be obtained. These measurements require no a priori knowledge of the pattern and very limited user interaction. The accuracy of the CHT is degraded by distortion introduced by the projector lens, and this should be minimised prior to pattern acquisition. A number of optimisations in the CHT software enable rapid processing of patterns; a typical analysis of a 1kx1k image taking just a few minutes. The CHT tool appears robust and is even able to accurately measure SADPs with very incomplete diffraction rings due to texture effects. This software tool is freely downloadable via the Internet

  10. Circular Hough transform diffraction analysis: A software tool for automated measurement of selected area electron diffraction patterns within Digital Micrograph{sup TM}

    Energy Technology Data Exchange (ETDEWEB)

    Mitchell, D.R.G. [Institute of Materials and Engineering Science, ANSTO, PMB 1, Menai, NSW 2234 (Australia)], E-mail: drm@ansto.gov.au

    2008-03-15

    A software tool (script and plugin) for computing circular Hough transforms (CHT) in Digital Micrograph{sup TM} has been developed, for the purpose of automated analysis of selected area electron diffraction patterns (SADPs) of polycrystalline materials. The CHT enables the diffraction pattern centre to be determined with sub-pixel accuracy, regardless of the exposure condition of the transmitted beam or if a beam stop is present. Radii of the diffraction rings can also be accurately measured with sub-pixel precision. If the pattern is calibrated against a known camera length, then d-spacings with an accuracy of better than 1% can be obtained. These measurements require no a priori knowledge of the pattern and very limited user interaction. The accuracy of the CHT is degraded by distortion introduced by the projector lens, and this should be minimised prior to pattern acquisition. A number of optimisations in the CHT software enable rapid processing of patterns; a typical analysis of a 1kx1k image taking just a few minutes. The CHT tool appears robust and is even able to accurately measure SADPs with very incomplete diffraction rings due to texture effects. This software tool is freely downloadable via the Internet.

  11. Crystallization and preliminary X-ray diffraction analysis of red clover necrotic mosaic virus

    International Nuclear Information System (INIS)

    Martin, Stanton L.; Guenther, Richard H.; Sit, Tim L.; Swartz, Paul D.; Meilleur, Flora; Lommel, Steven A.; Rose, Robert B.

    2010-01-01

    Virions of red clover necrotic mosaic virus have been purified and crystallized. The space group was determined to be I23, with unit-cell parameter a = 377.8 Å. The crystals diffracted to 4 Å resolution. Red clover necrotic mosaic virus (RCNMV) is a species that belongs to the Tombusviridae family of plant viruses with a T = 3 icosahedral capsid. RCNMV virions were purified and were crystallized for X-ray analysis using the hanging-drop vapor-diffusion method. Self-rotation functions and systematic absences identified the space group as I23, with two virions in the unit cell. The crystals diffracted to better than 4 Å resolution but were very radiation-sensitive, causing rapid decay of the high-resolution reflections. The data were processed to 6 Å in the analysis presented here

  12. Residual Stress Analysis for Engineering Applications by Means of Neutron Diffraction

    International Nuclear Information System (INIS)

    Gndupel-Herold, Thomas; Brand, Paul C.; Prask, Henry J.

    1999-01-01

    The economic and scientific importance of neutron diffraction residual stress analysis has led to an increasing number of suitable instruments worldwide. Recently, a dedicated state-of-the-art diffractometer has been installed at the National Institute of Standards and Technology reactor. It has been used for a variety of measurements on basic and engineering stress problems. Among the most prominent examples that have been investigated are residual stresses in rails, weldments, and plasma-sprayed coatings

  13. Crystals of DhaA mutants from Rhodococcus rhodochrous NCIMB 13064 diffracted to ultrahigh resolution: crystallization and preliminary diffraction analysis

    International Nuclear Information System (INIS)

    Stsiapanava, Alena; Koudelakova, Tana; Lapkouski, Mikalai; Pavlova, Martina; Damborsky, Jiri; Kuta Smatanova, Ivana

    2008-01-01

    Three mutants of the haloalkane dehalogenase DhaA derived from R. rhodochrous NCIMB 13064 were crystallized and diffracted to ultrahigh resolution. The enzyme DhaA from Rhodococcus rhodochrous NCIMB 13064 belongs to the haloalkane dehalogenases, which catalyze the hydrolysis of haloalkanes to the corresponding alcohols. The haloalkane dehalogenase DhaA and its variants can be used to detoxify the industrial pollutant 1,2,3-trichloropropane (TCP). Three mutants named DhaA04, DhaA14 and DhaA15 were constructed in order to study the importance of tunnels connecting the buried active site with the surrounding solvent to the enzymatic activity. All protein mutants were crystallized using the sitting-drop vapour-diffusion method. The crystals of DhaA04 belonged to the orthorhombic space group P2 1 2 1 2 1 , while the crystals of the other two mutants DhaA14 and DhaA15 belonged to the triclinic space group P1. Native data sets were collected for the DhaA04, DhaA14 and DhaA15 mutants at beamline X11 of EMBL, DESY, Hamburg to the high resolutions of 1.30, 0.95 and 1.15 Å, respectively

  14. 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.

  15. The purification, crystallization and preliminary X-ray diffraction analysis of dihydrodipicolinate synthase from Clostridium botulinum

    International Nuclear Information System (INIS)

    Dobson, Renwick C. J.; Atkinson, Sarah C.; Gorman, Michael A.; Newman, Janet M.; Parker, Michael W.; Perugini, Matthew A.

    2008-01-01

    Dihydrodipicolinate synthase (DHDPS), an enzyme in the lysine-biosynthetic pathway, is a promising target for antibiotic development against pathogenic bacteria. Here, the expression, purification, crystallization and preliminary diffraction analysis of DHDPS from C. botulinum are reported. In recent years, dihydrodipicolinate synthase (DHDPS; EC 4.2.1.52) has received considerable attention from both mechanistic and structural viewpoints. This enzyme, which is part of the diaminopimelate pathway leading to lysine, couples (S)-aspartate-β-semialdehyde with pyruvate via a Schiff base to a conserved active-site lysine. In this paper, the expression, purification, crystallization and preliminary X-ray diffraction analysis of DHDPS from Clostridium botulinum, an important bacterial pathogen, are presented. The enzyme was crystallized in a number of forms, predominantly using PEG precipitants, with the best crystal diffracting to beyond 1.9 Å resolution and displaying P4 2 2 1 2 symmetry. The unit-cell parameters were a = b = 92.9, c = 60.4 Å. The crystal volume per protein weight (V M ) was 2.07 Å 3 Da −1 , with an estimated solvent content of 41%. The structure of the enzyme will help guide the design of novel therapeutics against the C. botulinum pathogen

  16. Crystallization and preliminary X-ray diffraction analysis of diaminopimelate epimerase from Escherichia coli

    International Nuclear Information System (INIS)

    Hor, Lilian; Dobson, Renwick C. J.; Dogovski, Con; Hutton, Craig A.; Perugini, Matthew A.

    2009-01-01

    Diaminopimelate (DAP) epimerase, an enzyme in the lysine-biosynthetic pathway, is a promising target for antibiotic development against pathogenic bacteria. Here, the cloning, expression, purification, crystallization and preliminary diffraction analysis of DAP epimerase from E. coli are reported. Diaminopimelate (DAP) epimerase (EC 5.1.1.7) catalyzes the penultimate step of lysine biosynthesis in bacteria and plants, converting l,l-diaminopimelate to meso-diaminopimelate. Here, the cloning, expression, purification, crystallization and preliminary X-ray diffraction analysis of DAP epimerase from Escherichia coli are presented. Crystals were obtained in space group P4 1 2 1 2 and diffracted to 2.0 Å resolution, with unit-cell parameters a = b = 89.4, c = 179.6 Å. Molecular replacement was conducted using Bacillus anthracis DAP epimerase as a search model and showed the presence of two molecules in the asymmetric unit, with an initial R free of 0.456 and R work of 0.416

  17. Quantitative strain analysis of surfaces and interfaces using extremely asymmetric x-ray diffraction

    International Nuclear Information System (INIS)

    Akimoto, Koichi; Emoto, Takashi

    2010-01-01

    Strain can reduce carrier mobility and the reliability of electronic devices and affect the growth mode of thin films and the stability of nanometer-scale crystals. To control lattice strain, a technique for measuring the minute lattice strain at surfaces and interfaces is needed. Recently, an extremely asymmetric x-ray diffraction method has been developed for this purpose. By employing Darwin's dynamical x-ray diffraction theory, quantitative evaluation of strain at surfaces and interfaces becomes possible. In this paper, we review our quantitative strain analysis studies on native SiO 2 /Si interfaces, reconstructed Si surfaces, Ni/Si(111)-H interfaces, sputtered III-V compound semiconductor surfaces, high-k/Si interfaces, and Au ion-implanted Si. (topical review)

  18. Applications of the Warren-Averbach method of X-ray diffraction line profile analysis

    International Nuclear Information System (INIS)

    Ichikawa, Rodrigo Uchida

    2013-01-01

    The objective of this work was to develop and implement a methodology of X-ray Line Profile Analysis (XLPA) for the study and determination of the mean crystallite sizes and microstrains in materials. A computer program was developed to speed up the treatment of diffraction peaks and perform the deconvolution utilizing the Stokes method to correct the instrumental contribution in the X-ray diffraction measurements. The XLPA methods used were the Scherrer, Williamson-Hall and Single-Line methods, which can be called real space methods, and the Fourier space method of Warren-Averbach. Furthermore, considering a mathematical modelling it was possible to calculate the crystallite size distribution, considering the log-normal distribution and spherical crystallites. It was possible to demonstrate the proposed theory can provide reliable results evaluating a dispersion parameter. The methodologies described above were applied in two distinct materials: in the alloy Zircaloy-4 and in ZnO. (author)

  19. Atomic-layer-resolved analysis of surface magnetism by diffraction spectroscopy

    International Nuclear Information System (INIS)

    Matsui, Fumihiko; Matsushita, Tomohiro; Daimon, Hiroshi

    2010-01-01

    X-ray absorption near edge structure (XANES) and X-ray magnetic circular dichroism (XMCD) measurements by Auger-electron-yield detection are powerful analysis tools for the electronic and magnetic structures of surfaces, but all the information from atoms within the electron mean-free-path range is summed into the obtained spectrum. In order to investigate the electronic and magnetic structures of each atomic layer at subsurface, we have proposed a new method, diffraction spectroscopy, which is the combination of X-ray absorption spectroscopy and Auger electron diffraction (AED). From a series of measured thickness dependent AED patterns, we deduced a set of atomic-layer-specific AED patterns arithmetically. Based on these AED patterns, we succeeded in disentangling obtained XANES and XMCD spectra into those from different atomic layers.

  20. Ab-initio crystal structure analysis and refinement approaches of oligo p-benzamides based on electron diffraction data

    DEFF Research Database (Denmark)

    Gorelik, Tatiana E; van de Streek, Jacco; Kilbinger, Andreas F M

    2012-01-01

    Ab-initio crystal structure analysis of organic materials from electron diffraction data is presented. The data were collected using the automated electron diffraction tomography (ADT) technique. The structure solution and refinement route is first validated on the basis of the known crystal stru...

  1. X-ray diffraction analysis and in vitro characterization of the UAM2 protein from Oryza sativa

    DEFF Research Database (Denmark)

    Welner, Ditte Hededam; Tsai, Alex Yi-Lin; DeGiovanni, Andy M.

    2017-01-01

    protein from Oryza sativa (OsUAM2) were undertaken. Here, X-ray diffraction data are reported, as well as analysis of the oligomeric state in the crystal and in solution. OsUAM2 crystallizes readily but forms highly radiation-sensitive crystals with limited diffraction power, requiring careful low......, a requirement for a structural metal ion....

  2. 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.

  3. The materials science synchrotron beamline EDDI for energy-dispersive diffraction analysis

    International Nuclear Information System (INIS)

    Genzel, Ch.; Denks, I.A.; Gibmeier, J.; Klaus, M.; Wagener, G.

    2007-01-01

    In April 2005 the materials science beamline EDDI (Energy Dispersive DIffraction) at the Berlin synchrotron storage ring BESSY started operation. The beamline is operated in the energy-dispersive mode of diffraction using the high energy white photon beam provided by a superconducting 7 T multipole wiggler. Starting from basic information on the beamline set-up, its measuring facilities and data processing concept, the wide range of applications for energy-dispersive diffraction is demonstrated by a series of examples coming from different fields in materials sciences. It will be shown, that the EDDI beamline is especially suitable for the investigation of structural properties and gradients in the near surface region of polycrystalline materials. In particular, this concerns the analysis of multiaxial residual stress fields in the highly stressed surface zone of technical parts. The high photon flux further facilitates fast in situ experiments at room as well as high temperature to monitor for example the growth kinetics and reaction in thin film growth

  4. Crystal optimization and preliminary diffraction data analysis of the SCAN domain of Zfp206

    International Nuclear Information System (INIS)

    Liang, Yu; Choo, Siew Hua; Rossbach, Michael; Baburajendran, Nithya; Palasingam, Paaventhan; Kolatkar, Prasanna R

    2012-01-01

    Crystals of the SCAN domain of Zfp206 are tetragonal, belonging to space group I422 with unit-cell parameters a = 67.57, c = 87.54 Å and one molecule in the asymmetric unit, and diffract to 1.85 Å resolution. Zfp206 (also named Zscan10) is a transcription factor that plays an important role in maintaining the pluripotent state of embryonic stem cells. Zfp206 is a member of the SCAN-domain family of C 2 H 2 zinc-finger transcription factors. The SCAN domain is a highly conserved motif of 84 residues which mediates the self-association of and heterodimerization between SCAN-domain family transcription factors. The SCAN domain may therefore be the key to the selective oligomerization of and may combinatorially enhance the regulatory versatility of C 2 H 2 zinc fingers. This paper describes crystallization attempts with the SCAN domain of Zfp206 (Zfp206SCAN) and optimization strategies to obtain diffraction-quality crystals. The best diffracting crystal was grown in a solution consisting of 0.3 M ammonium sulfate, 0.1 M Tris–HCl pH 8.6, 25% PEG 3350, 0.1 M ethylenediaminetetraacetic acid disodium salt dehydrate (EDTA) using the hanging-drop vapour-diffusion technique. Optimized crystals diffracted to 1.85 Å resolution and belonged to space group I422, with unit-cell parameters a = 67.57, c = 87.54 Å. A Matthews analysis indicated the presence of one Zfp206SCAN molecule per asymmetric unit

  5. Comparison of dissimilarity measures for cluster analysis of X-ray diffraction data from combinatorial libraries

    Science.gov (United States)

    Iwasaki, Yuma; Kusne, A. Gilad; Takeuchi, Ichiro

    2017-12-01

    Machine learning techniques have proven invaluable to manage the ever growing volume of materials research data produced as developments continue in high-throughput materials simulation, fabrication, and characterization. In particular, machine learning techniques have been demonstrated for their utility in rapidly and automatically identifying potential composition-phase maps from structural data characterization of composition spread libraries, enabling rapid materials fabrication-structure-property analysis and functional materials discovery. A key issue in development of an automated phase-diagram determination method is the choice of dissimilarity measure, or kernel function. The desired measure reduces the impact of confounding structural data issues on analysis performance. The issues include peak height changes and peak shifting due to lattice constant change as a function of composition. In this work, we investigate the choice of dissimilarity measure in X-ray diffraction-based structure analysis and the choice of measure's performance impact on automatic composition-phase map determination. Nine dissimilarity measures are investigated for their impact in analyzing X-ray diffraction patterns for a Fe-Co-Ni ternary alloy composition spread. The cosine, Pearson correlation coefficient, and Jensen-Shannon divergence measures are shown to provide the best performance in the presence of peak height change and peak shifting (due to lattice constant change) when the magnitude of peak shifting is unknown. With prior knowledge of the maximum peak shifting, dynamic time warping in a normalized constrained mode provides the best performance. This work also serves to demonstrate a strategy for rapid analysis of a large number of X-ray diffraction patterns in general beyond data from combinatorial libraries.

  6. Data analysis of a polycrystalline nickel sample obtained with neutron diffraction

    International Nuclear Information System (INIS)

    Parente, C.B.R.; Mazzochi, V.L.; Araujo Kaschny, J.R. de; Costa, M.S. da; Rizzo, P.; Campos, W.M.S.

    1990-01-01

    A simple analysis of the nickel structure was made. Neutron diffraction data were used, obtained with polycrystalline nickel placed in a cylindrical sample-holder with dimensions of 1,5cm of diameter and 5cm of height. The theoretical intensities were calculated of 3 forms: 1. without considering the temperature and obsorption effects, 2. considering only the temperature effect and 3. considering both the temperature and absorption effects. The disagreement factors found in this 3 cases were, respectively, R 1 = 13.4%, R 2 = 7,7% e R 3 = 7,5%. (L.C.)

  7. Quantitative X-ray diffraction analysis of alumina, silicon carbide and zirconium carbide in ceramic composites

    International Nuclear Information System (INIS)

    Veiga, Sonia M.B.; Bressiani, Jose Carlos; Veiga, Marcello M.; Chaklader, Asoke C.D.

    1995-01-01

    The x-ray diffraction technique has been successfully applied to determine the phases formed in a carbo thermal synthesis of ceramic composites (Al 2 O 3 -Si C and Al 2 O 3 -Si C-Zr C) using kaolinite, cyanite and zircon as precursors. The powder method using fluorite as internal standard has shown reliable results to estimate accurately phases in composites (relative error as low as 5%). In addition, quantitative X-ray analysis allows an indirect evaluation of Si O (gas) losses from the system during the carbo thermal reaction. (author)

  8. Accurate measurement of the orientation relationship of lath martensite and bainite by electron backscatter diffraction analysis

    International Nuclear Information System (INIS)

    Miyamoto, G.; Takayama, N.; Furuhara, T.

    2009-01-01

    A new method to determine the orientation relationship between martensite and bainite with the parent austenite is developed based on electron backscatter diffraction analysis. This method can determine the orientation relationship accurately without the presence of retained austenite, and is applicable to lath martensite and bainite in low-alloyed carbon steels. The angles between close-packed directions are about 3 o for lath martensite regardless of the carbon content, while the angles between close-packed planes become smaller with increasing carbon content.

  9. Measurement and analysis of field-induced crystallographic texture using curved position-sensitive diffraction detectors

    DEFF Research Database (Denmark)

    Simons, Hugh; Daniels, John E.; Studer, Andrew J.

    2014-01-01

    This paper outlines measurement and analysis methodologies created for determining the structural responses of electroceramics to an electric field. A sample stage is developed to apply electric fields to ceramic materials at elevated temperatures during neutron diffraction experiments. The tested...... employing a curved positive sensitive detector. Methodologies are proposed to account for the geometrical effects when vector fields are applied to textured materials with angularly dispersive detector geometries. Representative results are presented for the ferroelectric (Bi1/2Na1/2)TiO3-6%BaTiO3 (BNT-6BT...

  10. Hybrid Powder - Single Crystal X-Ray Diffraction Instrument for Planetary Mineralogical Analysis of Unprepared Samples, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose to develop a planetary exploration XRD/XRF instrument based on a hybrid diffraction approach that complements powder XRD analysis, similar to that of the...

  11. A standardless method of quantitative ceramic analysis using X-ray powder diffraction

    International Nuclear Information System (INIS)

    Mazumdar, S.

    1999-01-01

    A new procedure using X-ray powder diffraction data for quantitative estimation of the crystalline as well as the amorphous phase in ceramics is described. Classification of the crystalline and amorphous X-ray scattering was achieved by comparison of the slopes at two successive points of the powder pattern at scattering angles at which the crystalline and amorphous phases superimpose. If the second slope exceeds the first by a stipulated value, the intensity is taken as crystalline; otherwise the scattering is considered as amorphous. Crystalline phase analysis is obtained by linear programming techniques using the concept that each observed X-ray diffraction peak has contributions from n component phases, the proportionate analysis of which is required. The method does not require the measurement of calibration data for use as an internal standard, but knowledge of the approximate crystal structure of each phase of interest in the mixture is necessary. The technique is also helpful in qualitative analysis because each suspected phase is characterized by the probability that it will be present when a reflection zone is considered in which the suspected crystalline phase could contribute. The amorphous phases are determined prior to the crystalline ones. The method is applied to ceramic materials and some results are presented. (orig.)

  12. A Monte Carlo error simulation applied to calibration-free X-ray diffraction phase analysis

    International Nuclear Information System (INIS)

    Braun, G.E.

    1986-01-01

    Quantitative phase analysis of a system of n phases can be effected without the need for calibration standards provided at least n different mixtures of these phases are available. A series of linear equations relating diffracted X-ray intensities, weight fractions and quantitation factors coupled with mass balance relationships can be solved for the unknown weight fractions and factors. Uncertainties associated with the measured X-ray intensities, owing to counting of random X-ray quanta, are used to estimate the errors in the calculated parameters utilizing a Monte Carlo simulation. The Monte Carlo approach can be generalized and applied to any quantitative X-ray diffraction phase analysis method. Two examples utilizing mixtures of CaCO 3 , Fe 2 O 3 and CaF 2 with an α-SiO 2 (quartz) internal standard illustrate the quantitative method and corresponding error analysis. One example is well conditioned; the other is poorly conditioned and, therefore, very sensitive to errors in the measured intensities. (orig.)

  13. Analysis of rocks involving the x-ray diffraction, infrared and thermal gravimetric techniques

    International Nuclear Information System (INIS)

    Ikram, M.; Rauf, M.A.; Munir, N.

    1998-01-01

    Chemical analysis of rocks and minerals are usually obtained by a number of analytical techniques. The purpose of present work is to investigate the chemical composition of the rock samples and also to find that how far the results obtained by different instrumental methods are closely related. Chemical tests wee performed before using the instrumental techniques in order to determined the nature of these rocks. The chemical analysis indicated mainly the presence of carbonate and hence the carbonate nature of these rocks. The x-ray diffraction, infrared spectroscopy and thermal gravimetric analysis techniques were used for the determination of chemical composition of these samples. The results obtained by using these techniques have shown a great deal of similarities. (author)

  14. Powder diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Hart, M.

    1995-12-31

    the importance of x-ray powder diffraction as an analytical tool for phase identification of materials was first pointed out by Debye and Scherrer in Germany and, quite independently, by Hull in the US. Three distinct periods of evolution lead to ubiquitous application in many fields of science and technology. In the first period, until the mid-1940`s, applications were and developed covering broad categories of materials including inorganic materials, minerals, ceramics, metals, alloys, organic materials and polymers. During this formative period, the concept of quantitative phase analysis was demonstrated. In the second period there followed the blossoming of technology and commercial instruments became widely used. The history is well summarized by Parrish and by Langford and Loueer. By 1980 there were probably 10,000 powder diffractometers in routine use, making it the most widely used of all x-ray crystallographic instruments. In the third, present, period data bases became firmly established and sophisticated pattern fitting and recognition software made many aspects of powder diffraction analysis routine. High resolution, tunable powder diffractometers were developed at sources of synchrotron radiation. The tunability of the spectrum made it possible to exploit all the subtleties of x-ray spectroscopy in diffraction experiments.

  15. Powder diffraction

    International Nuclear Information System (INIS)

    Hart, M.

    1995-01-01

    The importance of x-ray powder diffraction as an analytical tool for phase identification of materials was first pointed out by Debye and Scherrer in Germany and, quite independently, by Hull in the US. Three distinct periods of evolution lead to ubiquitous application in many fields of science and technology. In the first period, until the mid-1940's, applications were and developed covering broad categories of materials including inorganic materials, minerals, ceramics, metals, alloys, organic materials and polymers. During this formative period, the concept of quantitative phase analysis was demonstrated. In the second period there followed the blossoming of technology and commercial instruments became widely used. The history is well summarized by Parrish and by Langford and Loueer. By 1980 there were probably 10,000 powder diffractometers in routine use, making it the most widely used of all x-ray crystallographic instruments. In the third, present, period data bases became firmly established and sophisticated pattern fitting and recognition software made many aspects of powder diffraction analysis routine. High resolution, tunable powder diffractometers were developed at sources of synchrotron radiation. The tunability of the spectrum made it possible to exploit all the subtleties of x-ray spectroscopy in diffraction experiments

  16. Characterization of the Roraima savanna across of X-ray diffraction, thermomagnetic analysis and Moessbauer spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Gilmar A.; Araujo, R.C.; Sergio, C.S. [Universidade Federal de Roraima (UFRR), Boa Vista, RR (Brazil)

    2012-07-01

    Full text: The technique of X-ray diffraction has great resolving power to determine the phases present in crystalline material, thereby enabling it to determine the elements present in the materials as well as changes in structure that they can suffer when subjected to various physical processes and/or chemical means. The research had as objective to characterize the mineralogy of iron oxides, silicon, aluminum and other minerals in the soil of five points of the Roraima savannah. The points where samples were collected are five municipalities in the state of Roraima. The area of sampling is part of the savanna in Roraima. The samples were collected. We analyzed samples from five points from the collection of natural soil in the locations listed. The samples were placed in a mill to a uniform grain size. After the milling process, the magnetic material was separated using a permanent magnet. Then the samples were analyzed by x-ray diffraction, thermomagnetic analysis and Moessbauer spectroscopy. Preliminary results of XRD showed the occurrence of phases of oxides of iron, silicon, aluminum and other phases less. Thermomagnetic analysis show that the magnetic phases are magnetite and hematite. The results of the Moessbauer spectroscopy indicates the reliability in the two prior art and confirmed the presence of the phases of oxides of iron present in the soil analyzed. (author)

  17. X-ray diffraction analysis of synthesized silver nanohexagon for the study of their mechanical properties

    Energy Technology Data Exchange (ETDEWEB)

    Das, Ratan, E-mail: dasratanphy@gmail.com; Sarkar, Sumit, E-mail: sarkarsumit07phy@gmail.com

    2015-11-01

    Silver nanohexagons have been prepared through the chemical reduction method using poly(vinyl pyrrolidone) (PVP) as a capping agent. High Resolution Transmission Electron Microscopic (HRTEM) study shows that average size of the prepared silver nanoparticles is 45 nm approximately with nearly hexagon shape. The peaks in the X-Ray Diffraction (XRD) pattern are in good agreement with that of face centered cubic structure. Williamson–Hall plots (W–H plot) have been analyzed to study the crystalline size and lattice strain considering the peak broadening of the AgNHs. The mechanical properties such as strain, stress and energy density of prepared nanohexagon have been calculated assuming uniform deformation model (UDM), uniform stress deformation model (USDM), and uniform deformation energy density model (UDEDM) and size–strain plot method (SSP). From all these results, it is found that the size and strain estimated from W–H analysis and SSP method are in good agreement. - Highlights: • PVP capped silver nanohexagons have been synthesized by chemical reduction method. • HRTEM images show that the average size of the prepared nanohexagons is 45 nm. • X-ray diffraction study confirms the crystallinity of silver nanohexagons. • Elastic properties have been calculated by W–H analysis using different models. • Further, the results from UDM, USDM, and UDEDM matches with SSP method.

  18. Measurement and QCD Analysis of the Diffractive Deep-Inelastic Scattering Cross Section at HERA

    CERN Document Server

    Aktas, A.; Anthonis, T.; Antunovic, B.; Aplin, S.; Asmone, A.; Astvatsatourov, A.; Babaev, A.; Backovic, S.; Baghdasaryan, A.; Baranov, P.; Barrelet, E.; Bartel, W.; Baudrand, S.; Baumgartner, S.; Beckingham, M.; Behnke, O.; Behrendt, O.; Belousov, A.; Berger, N.; Bizot, J.C.; Boenig, M.O.; Boudry, V.; Bracinik, J.; Brandt, G.; Brisson, V.; Bruncko, D.; Busser, F.W.; Bunyatyan, A.; Buschhorn, G.; Bystritskaya, L.; Campbell, A.J.; Cassol-Brunner, F.; Cerny, K.; Cerny, V.; Chekelian, V.; Contreras, J.G.; Coughlan, J.A.; Coppens, Y.R.; Cox, B.E.; Cozzika, G.; Cvach, J.; Dainton, J.B.; Dau, W.D.; Daum, K.; de Boer, Y.; Delcourt, B.; Del Degan, M.; De Roeck, A.; De Wolf, E.A.; Diaconu, C.; Dodonov, V.; Dubak, A.; Eckerlin, G.; Efremenko, V.; Egli, S.; Eichler, R.; Eisele, F.; Eliseev, A.; Elsen, E.; Essenov, S.; Falkewicz, A.; Faulkner, P.J.W.; Favart, L.; Fedotov, A.; Felst, R.; Feltesse, J.; Ferencei, J.; Finke, L.; Fleischer, M.; Flucke, G.; Fomenko, A.; Franke, G.; Frisson, T.; Gabathuler, E.; Garutti, E.; Gayler, J.; Gerlich, C.; Ghazaryan, S.; Ginzburgskaya, S.; Glazov, A.; Glushkov, I.; Goerlich, L.; Goettlich, M.; Gogitidze, N.; Gorbounov, S.; Grab, C.; Greenshaw, T.; Gregori, M.; Grell, B.R.; Grindhammer, G.; Gwilliam, C.; Haidt, D.; Hansson, M.; Heinzelmann, G.; Henderson, R.C.W.; Henschel, H.; Herrera, G.; Hildebrandt, M.; Hiller, K.H.; Hoffmann, D.; Horisberger, R.; Hovhannisyan, A.; Hreus, T.; Hussain, S.; Ibbotson, M.; Ismail, M.; Jacquet, M.; Janssen, X.; Jemanov, V.; Jonsson, L.; Johnson, C.L.; Johnson, D.P.; Jung, A.W.; Jung, H.; Kapichine, M.; Katzy, J.; Kenyon, I.R.; Kiesling, C.; Klein, M.; Kleinwort, C.; Klimkovich, T.; Kluge, T.; Knies, G.; Knutsson, A.; Korbel, V.; Kostka, P.; Krastev, K.; Kretzschmar, J.; Kropivnitskaya, A.; Kruger, K.; Landon, M.P.J.; Lange, W.; Lastovicka-Medin, G.; Laycock, P.; Lebedev, A.; Leibenguth, G.; Lendermann, V.; Levonian, S.; Lindfeld, L.; Lipka, K.; Liptaj, A.; List, B.; List, J.; Lobodzinska, E.; Loktionova, N.; Lopez-Fernandez, R.; Lubimov, V.; Lucaci-Timoce, A.I.; Lueders, H.; Lux, T.; Lytkin, L.; Makankine, A.; Malden, N.; Malinovski, E.; Marage, P.; Marshall, R.; Marti, L.; Martisikova, M.; Martyn, H.U.; Maxfield, S.J.; Mehta, A.; Meier, K.; Meyer, A.B.; Meyer, H.; Meyer, J.; Michels, V.; Mikocki, S.; Milcewicz-Mika, I.; Milstead, D.; Mladenov, D.; Mohamed, A.; Moreau, F.; Morozov, A.; Morris, J.V.; Mozer, M.U.; Muller, K.; Murin, P.; Nankov, K.; Naroska, B.; Naumann, T.; Newman, P.R.; Niebuhr, C.; Nikiforov, A.; Nowak, G.; Nowak, K.; Nozicka, M.; Oganezov, R.; Olivier, B.; Olsson, J.E.; Osman, S.; Ozerov, D.; Palichik, V.; Panagoulias, I.; Papadopoulou, T.; Pascaud, C.; Patel, G.D.; Peng, H.; Perez, E.; Perez-Astudillo, D.; Perieanu, A.; Petrukhin, A.; Pitzl, D.; Placakyte, R.; Portheault, B.; Povh, B.; Prideaux, P.; Rahmat, A.J.; Raicevic, N.; Reimer, P.; Rimmer, A.; Risler, C.; Rizvi, E.; Robmann, P.; Roland, B.; Roosen, R.; Rostovtsev, A.; Rurikova, Z.; Rusakov, S.; Salvaire, F.; Sankey, D.P.C.; Sauter, M.; Sauvan, E.; Schilling, F.P.; Schmidt, S.; Schmitt, S.; Schmitz, C.; Schoeffel, L.; Schoning, A.; Schultz-Coulon, H.C.; Sefkow, F.; Shaw-West, R.N.; Sheviakov, I.; Shtarkov, L.N.; Sloan, T.; Smirnov, P.; Soloviev, Y.; South, D.; Spaskov, V.; Specka, A.; Steder, M.; Stella, B.; Stiewe, J.; Stoilov, A.; Straumann, U.; Sunar, D.; Tchoulakov, V.; Thompson, G.; Thompson, P.D.; Toll, T.; Tomasz, F.; Traynor, D.; Trinh, T.N.; Truol, P.; Tsakov, I.; Tsipolitis, G.; Tsurin, I.; Turnau, J.; Tzamariudaki, E.; Urban, K.; Urban, M.; Usik, A.; Utkin, D.; Valkarova, A.; Vallee, C.; Van Mechelen, P.; Vargas Trevino, A.; Vazdik, Y.; Veelken, C.; Vinokurova, S.; Volchinski, V.; Wacker, K.; Weber, G.; Weber, R.; Wegener, D.; Werner, C.; Wessels, M.; Wessling, B.; Wissing, C.; Wolf, R.; Wunsch, E.; Xella, S.; Yan, W.; Yeganov, V.; Zacek, J.; Zalesak, J.; Zhang, Z.; Zhelezov, A.; Zhokin, A.; Zhu, Y.C.; Zimmermann, J.; Zimmermann, T.; Zohrabyan, H.; Zomer, F.

    2006-01-01

    A detailed analysis is presented of the diffractive deep-inelastic scattering process $ep\\to eXY$, where $Y$ is a proton or a low mass proton excitation carrying a fraction $1 - \\xpom > 0.95$ of the incident proton longitudinal momentum and the squared four-momentum transfer at the proton vertex satisfies $|t|<1 {\\rm GeV^2}$. Using data taken by the H1 experiment, the cross section is measured for photon virtualities in the range $3.5 \\leq Q^2 \\leq 1600 \\rm GeV^2$, triple differentially in $\\xpom$, $Q^2$ and $\\beta = x / \\xpom$, where $x$ is the Bjorken scaling variable. At low $\\xpom$, the data are consistent with a factorisable $\\xpom$ dependence, which can be described by the exchange of an effective pomeron trajectory with intercept $\\alphapom(0)= 1.118 \\pm 0.008 {\\rm (exp.)} ^{+0.029}_{-0.010} {\\rm (model)}$. Diffractive parton distribution functions and their uncertainties are determined from a next-to-leading order DGLAP QCD analysis of the $Q^2$ and $\\beta$ dependences of the cross section. The res...

  19. X-ray diffraction from thin films : Size/strain analysis and whole pattern fitting

    Energy Technology Data Exchange (ETDEWEB)

    Scardi, P [Trento Univ. (Italy). Dept. of Materials Engineering

    1996-09-01

    Line Profile Analysis (LPA) and whole pattern fitting may be used with success for the characterization of thin films from XRD data collected with the traditional Bragg-Brentano geometry. The size/strain analysis was conducted by an integrated procedure of profile modelling-assisted Fourier analysis, in order to measure the content of lattice imperfections and crystalline domain size along the growth direction in heteroepitaxial thin films. The microstructure of these films is typical of several PVD processes for the production of highly textured and low-defect thin crystalline layers. The same analysis could be conducted on random thin films as well, and in this case it is possible to determine an average crystallite size and shape. As will be shown in the paper, structural and microstructural parameters obtained by these methods may be correlated with thin film properties of technological interest. The whole pattern analysis may be used to obtain the information contained in a wide region of the diffraction pattern. This approach, currently used for the quantitative analysis of phase mixtures in traditional powder samples, was modified to account both for the size/strain effects, according to a simplified LPA, and for the structure of thin films and multi-layer systems. In this way, a detailed analysis based on a structural model for the present phases can be performed considering the real geometry of these samples. In particular, the quantitative phase analysis could be conducted in terms of layer thickness instead of volume or weight fractions.

  20. X-ray diffraction from thin films : Size/strain analysis and whole pattern fitting

    International Nuclear Information System (INIS)

    Scardi, P.

    1996-01-01

    Line Profile Analysis (LPA) and whole pattern fitting may be used with success for the characterization of thin films from XRD data collected with the traditional Bragg-Brentano geometry. The size/strain analysis was conducted by an integrated procedure of profile modelling-assisted Fourier analysis, in order to measure the content of lattice imperfections and crystalline domain size along the growth direction in heteroepitaxial thin films. The microstructure of these films is typical of several PVD processes for the production of highly textured and low-defect thin crystalline layers. The same analysis could be conducted on random thin films as well, and in this case it is possible to determine an average crystallite size and shape. As will be shown in the paper, structural and microstructural parameters obtained by these methods may be correlated with thin film properties of technological interest. The whole pattern analysis may be used to obtain the information contained in a wide region of the diffraction pattern. This approach, currently used for the quantitative analysis of phase mixtures in traditional powder samples, was modified to account both for the size/strain effects, according to a simplified LPA, and for the structure of thin films and multi-layer systems. In this way, a detailed analysis based on a structural model for the present phases can be performed considering the real geometry of these samples. In particular, the quantitative phase analysis could be conducted in terms of layer thickness instead of volume or weight fractions

  1. Tensometry technique for X-ray diffraction in applied analysis of welding

    International Nuclear Information System (INIS)

    Turibus, S.N.; Caldas, F.C.M.; Miranda, D.M.; Monine, V.I.; Assis, J.T.

    2010-01-01

    This paper presents the analysis of residual stress introduced in welding process. As the stress in a material can induce damages, it is necessary to have a method to identify this residual stress state. For this it was used the non-destructive X-ray diffraction technique to analyze two plates from A36 steel jointed by metal inert gas (MIG) welding. The stress measurements were made by the sin 2 ψ method in weld region of steel plates including analysis of longitudinal and transverse residual stresses in fusion zone, heat affected zone (HAZ) and base metal. To determine the stress distribution along the depth of the welded material it was used removing of superficial layers made by electropolishing. (author)

  2. [Desmoid fibromatosis in absorption infrared spectroscopy, emission spectral analysis and roentgen diffraction recording].

    Science.gov (United States)

    Zejkan, A; Bejcek, Z; Horejs, J; Vrbová, H; Bakosová, M; Macholda, F; Rykl, D

    1989-10-01

    The authors present results of serial quality and quantity microanalyses of bone patterns and dental tissue patterns in patient with desmoid fibromatosis. Methods of absorption spectroscopy, emission spectral analysis and X-ray diffraction analysis with follow-up to x-ray examination are tested. The above mentioned methods function in a on-line system by means of specially adjusted monitor unit which is controlled centrally by the computer processor system. The whole process of measurement is fully automated and the data obtained are recorded processed in the unit data structure classified into index sequence blocks of data. Serial microanalyses offer exact data for the study of structural changes of dental and bone tissues which manifest themselves in order of crystal grid shifts. They prove the fact that microanalyses give new possibilities in detection and interpretation of chemical and structural changes of apatite cell.

  3. Thermal and X-ray diffraction analysis studies during the decomposition of ammonium uranyl nitrate

    OpenAIRE

    Kim, B. H.; Lee, Y. B.; Prelas, M. A.; Ghosh, T. K.

    2012-01-01

    Two types of ammonium uranyl nitrate (NH4)2UO2(NO3)4?2H2O and NH4UO2(NO3)3, were thermally decomposed and reduced in a TG-DTA unit in nitrogen, air, and hydrogen atmospheres. Various intermediate phases produced by the thermal decomposition and reduction process were investigated by an X-ray diffraction analysis and a TG/DTA analysis. Both (NH4)2UO2(NO3)4?2H2O and NH4UO2(NO3)3 decomposed to amorphous UO3 regardless of the atmosphere used. The amorphous UO3 from (NH4)2UO2(NO3)4?2H2O was crysta...

  4. Accelerated Synchrotron X-ray Diffraction Data Analysis on a Heterogeneous High Performance Computing System

    Energy Technology Data Exchange (ETDEWEB)

    Qin, J; Bauer, M A, E-mail: qin.jinhui@gmail.com, E-mail: bauer@uwo.ca [Computer Science Department, University of Western Ontario, London, ON N6A 5B7 (Canada)

    2010-11-01

    The analysis of synchrotron X-ray Diffraction (XRD) data has been used by scientists and engineers to understand and predict properties of materials. However, the large volume of XRD image data and the intensive computations involved in the data analysis makes it hard for researchers to quickly reach any conclusions about the images from an experiment when using conventional XRD data analysis software. Synchrotron time is valuable and delays in XRD data analysis can impact decisions about subsequent experiments or about materials that they are investigating. In order to improve the data analysis performance, ideally to achieve near real time data analysis during an XRD experiment, we designed and implemented software for accelerated XRD data analysis. The software has been developed for a heterogeneous high performance computing (HPC) system, comprised of IBM PowerXCell 8i processors and Intel quad-core Xeon processors. This paper describes the software and reports on the improved performance. The results indicate that it is possible for XRD data to be analyzed at the rate it is being produced.

  5. Accelerated Synchrotron X-ray Diffraction Data Analysis on a Heterogeneous High Performance Computing System

    International Nuclear Information System (INIS)

    Qin, J; Bauer, M A

    2010-01-01

    The analysis of synchrotron X-ray Diffraction (XRD) data has been used by scientists and engineers to understand and predict properties of materials. However, the large volume of XRD image data and the intensive computations involved in the data analysis makes it hard for researchers to quickly reach any conclusions about the images from an experiment when using conventional XRD data analysis software. Synchrotron time is valuable and delays in XRD data analysis can impact decisions about subsequent experiments or about materials that they are investigating. In order to improve the data analysis performance, ideally to achieve near real time data analysis during an XRD experiment, we designed and implemented software for accelerated XRD data analysis. The software has been developed for a heterogeneous high performance computing (HPC) system, comprised of IBM PowerXCell 8i processors and Intel quad-core Xeon processors. This paper describes the software and reports on the improved performance. The results indicate that it is possible for XRD data to be analyzed at the rate it is being produced.

  6. Quantitative analysis of crystalline pharmaceuticals in tablets by pattern-fitting procedure using X-ray diffraction pattern.

    Science.gov (United States)

    Takehira, Rieko; Momose, Yasunori; Yamamura, Shigeo

    2010-10-15

    A pattern-fitting procedure using an X-ray diffraction pattern was applied to the quantitative analysis of binary system of crystalline pharmaceuticals in tablets. Orthorhombic crystals of isoniazid (INH) and mannitol (MAN) were used for the analysis. Tablets were prepared under various compression pressures using a direct compression method with various compositions of INH and MAN. Assuming that X-ray diffraction pattern of INH-MAN system consists of diffraction intensities from respective crystals, observed diffraction intensities were fitted to analytic expression based on X-ray diffraction theory and separated into two intensities from INH and MAN crystals by a nonlinear least-squares procedure. After separation, the contents of INH were determined by using the optimized normalization constants for INH and MAN. The correction parameter including all the factors that are beyond experimental control was required for quantitative analysis without calibration curve. The pattern-fitting procedure made it possible to determine crystalline phases in the range of 10-90% (w/w) of the INH contents. Further, certain characteristics of the crystals in the tablets, such as the preferred orientation, size of crystallite, and lattice disorder were determined simultaneously. This method can be adopted to analyze compounds whose crystal structures are known. It is a potentially powerful tool for the quantitative phase analysis and characterization of crystals in tablets and powders using X-ray diffraction patterns. Copyright 2010 Elsevier B.V. All rights reserved.

  7. Quantitative description of microstructure defects in hexagonal boron nitrides using X-ray diffraction analysis

    International Nuclear Information System (INIS)

    Schimpf, C.; Motylenko, M.; Rafaja, D.

    2013-01-01

    A routine for simultaneous quantification of turbostratic disorder, amount of puckering and the dislocation and stacking fault density in hexagonal materials was proposed and tested on boron nitride powder samples that were synthesised using different methods. The routine allows the individual microstructure defects to be recognised according to their effect on the anisotropy of the X-ray diffraction line broadening. For quantification of the microstructure defects, the total line broadening is regarded as a linear combination of the contributions from the particular defects. The total line broadening is obtained from the line profile fitting. As testing material, graphitic boron nitride (h-BN) was employed in the form of hot-isostatically pressed h-BN, pyrolytic h-BN or a h-BN, which was chemically vapour deposited at a low temperature. The kind of the dominant microstructure defects determined from the broadening of the X-ray diffraction lines was verified by high resolution transmission electron microscopy. Their amount was attempted to be verified by alternative methods. - Highlights: • Reliable method for quantification of microstructure defects in BN was suggested. • The method is based on the analysis of anisotropic XRD line broadening. • This XRD line broadening is unique and characteristic of the respective defect. • Thus, the quantification of coexistent microstructure defects is possible. • The method was tested on hexagonal BN, which was produced by different techniques

  8. Diffraction analysis of sidelobe characteristics of optical elements with ripple error

    Science.gov (United States)

    Zhao, Lei; Luo, Yupeng; Bai, Jian; Zhou, Xiangdong; Du, Juan; Liu, Qun; Luo, Yujie

    2018-03-01

    The ripple errors of the lens lead to optical damage in high energy laser system. The analysis of sidelobe on the focal plane, caused by ripple error, provides a reference to evaluate the error and the imaging quality. In this paper, we analyze the diffraction characteristics of sidelobe of optical elements with ripple errors. First, we analyze the characteristics of ripple error and build relationship between ripple error and sidelobe. The sidelobe results from the diffraction of ripple errors. The ripple error tends to be periodic due to fabrication method on the optical surface. The simulated experiments are carried out based on angular spectrum method by characterizing ripple error as rotationally symmetric periodic structures. The influence of two major parameter of ripple including spatial frequency and peak-to-valley value to sidelobe is discussed. The results indicate that spatial frequency and peak-to-valley value both impact sidelobe at the image plane. The peak-tovalley value is the major factor to affect the energy proportion of the sidelobe. The spatial frequency is the major factor to affect the distribution of the sidelobe at the image plane.

  9. High quality transmission Kikuchi diffraction analysis of deformed alloys - Case study

    International Nuclear Information System (INIS)

    Tokarski, Tomasz; Cios, Grzegorz; Kula, Anna; Bała, Piotr

    2016-01-01

    Modern scanning electron microscopes (SEM) equipped with thermally assisted field emission guns (Schottky FEG) are capable of imaging with a resolution in the range of several nanometers or better. Simultaneously, the high electron beam current can be used, which enables fast chemical and crystallographic analysis with a higher resolution than is normally offered by SEM with a tungsten cathode. The current resolution that limits the EDS and EBSD analysis is related to materials' physics, particularly to the electron-specimen interaction volume. The application of thin, electron-transparent specimens, instead of bulk samples, improves the resolution and allows for the detailed analysis of very fine microstructural features. Beside the typical imaging mode, it is possible to use a standard EBSD camera in such a configuration that only transmitted and scattered electrons are detected. This modern approach was successfully applied to various materials giving rise to significant resolution improvement, especially for the light element magnesium based alloys. This paper presents an insight into the application of the transmission Kikuchi diffraction (TKD) technique applied to the most troublesome, heavily-deformed materials. In particular, the values of the highest possible acquisition rates for high resolution and high quality mapping were estimated within typical imaging conditions of stainless steel and magnesium-yttrium alloy. - Highlights: •Monte Carlo simulations were used to simulate EBSD camera intensity for various measuring conditions. •Transmission Kikuchi diffraction parameters were evaluated for highly deformed, light and heavy elements based alloys. •High quality maps with 20 nm spatial resolution were acquired for Mg and Fe based alloys. •High speed TKD measurements were performed at acquisition rates comparable to the reflection EBSD.

  10. Evaluation of Portland cement from X-ray diffraction associated with cluster analysis

    International Nuclear Information System (INIS)

    Gobbo, Luciano de Andrade; Montanheiro, Tarcisio Jose; Montanheiro, Filipe; Sant'Agostino, Lilia Mascarenhas

    2013-01-01

    The Brazilian cement industry produced 64 million tons of cement in 2012, with noteworthy contribution of CP-II (slag), CP-III (blast furnace) and CP-IV (pozzolanic) cements. The industrial pole comprises about 80 factories that utilize raw materials of different origins and chemical compositions that require enhanced analytical technologies to optimize production in order to gain space in the growing consumer market in Brazil. This paper assesses the sensitivity of mineralogical analysis by X-ray diffraction associated with cluster analysis to distinguish different kinds of cements with different additions. This technique can be applied, for example, in the prospection of different types of limestone (calcitic, dolomitic and siliceous) as well as in the qualification of different clinkers. The cluster analysis does not require any specific knowledge of the mineralogical composition of the diffractograms to be clustered; rather, it is based on their similarity. The materials tested for addition have different origins: fly ashes from different power stations from South Brazil and slag from different steel plants in the Southeast. Cement with different additions of limestone and white Portland cement were also used. The Rietveld method of qualitative and quantitative analysis was used for measuring the results generated by the cluster analysis technique. (author)

  11. A re-analysis of neutron diffraction data from UO2

    International Nuclear Information System (INIS)

    Cooper, M.J.; Sakata, M.

    1979-04-01

    The results of a re-analysis of recent single crystal and powder neutron diffraction data from UO2 are presented and discussed. It is shown that apparent inconsistencies in the results of previous analyses of these data arose from differences between the values assumed for some of the parameters and that the various sets of data are in fact extremely consistent. These data also provide a more accurate value for the ratio of the scattering amplitudes, i.e. bU/bO = 1.451(2), which gives a value for bU = 0.842(2) x 10(-12) cm on the assumption of a value for b0 = 0.5805(11) x 10(-12) cm. The temperature factors for the atoms at room temperature are determined to be BU = 0.23(1)Angstrom and BO = 0.44(1)Angstrom(2). (author)

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

    DEFF Research Database (Denmark)

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

    1998-01-01

    We report a detailed structural analysis of the phases of 1,2-sn-dipalmitoylglycerol Langmuir monolayers at room temperature. Pressure-induced transitions have been investigated by combination of molecular-dynamics simulations and grazing-incidence x-ray diffraction (XRD). The diglyceride film...... undergoes two phase transitions occurring at 38.3 and 39.8 Angstrom(2)/molecule. Simulation indicates that the first transition involves a reorientation of the headgroups while simulation and XRD show that in the second transition the order parameter is the tilt angle of the alkyl chains. A methodology......; At the lowest pressure the tilt angle reaches approximate to 14 degrees in a direction close to a nearest neighbor direction. Both arrangements of the alkyl chains are confirmed by XRD. For higher order and fractional order Bragg peaks, simulations predict higher intensities than observed with XRD. This may...

  13. Quantitative mineralogical analysis of sandstones using x-ray diffraction techniques

    International Nuclear Information System (INIS)

    Ward, C.R.; Taylor, J.C.

    1999-01-01

    Full text: X-ray diffraction has long been used as a definitive technique for mineral identification based on the measuring the internal atomic or crystal structures present in powdered rocks; soils and other mineral mixtures. Recent developments in data gathering and processing, however, have provided an improved basis for its use as a quantitative tool, determining not only the nature of the minerals but also the relative proportions of the different minerals present. The mineralogy of a series of sandstone samples from the Sydney and Bowen Basins of eastern Australia has been evaluated by X-ray diffraction (XRD) on a quantitative basis using the Australian-developed SIROQUANT data processing technique. Based on Rietveld principles, this technique generates a synthetic X-ray diffractogram by adjusting and combining full-profile patterns of minerals nominated as being present in the sample and interactively matches the synthetic diffractogram under operator instructions to the observed diffractogram of the sample being analysed. The individual mineral patterns may be refined in the process, to allow for variations in crystal structure of individual components or for factors such as preferred orientation in the sample mount. The resulting output provides mass percentages of the different minerals in the mixture, and an estimate of the error associated with each individual percentage determination. The chemical composition of the mineral mixtures indicated by SIROQUANT for each individual sandstone studied was estimated using a spreadsheet routine, and the indicated proportion of each oxide in each sample compared to the actual chemical analysis of the same sandstone as determined independently by X-ray fluorescence spectrometry. The results show a high level of agreement for all major chemical constituents, indicating consistency between the SIROQUANT XRD data and the whole-rock chemical composition. Supplementary testing with a synthetic corundum spike further

  14. X-ray diffraction analysis of clay stones, Muglad Sedimentary Basin, Sudan

    International Nuclear Information System (INIS)

    Ali, A. E.

    1997-01-01

    This study deals with the theoretical and experimental aspects of X-ray diffraction (XRD) technique. Moreover the XRD technique has been used to investigate the clay mineral types and their distribution for samples obtained from exploration wells in the Mugald Sedimentary Basin in Western Sudan. The studied samples range in depth from 1524 m to 4572 m. The XRD analysis of samples shows that they consist of kaolinite, smectite, illite, chlorite and the mixed-layer smectite/illite. Kaolinite has higher abundance (15 - 72 %) followed by illite (7 - 34 %), smectite (11 - 76 %) and the less abundance of chlorite and the mixed-layer smectite/illite. Non-clay minerals found include quartz and cristabolite. The clay mineral types and their vertical distribution reflect various controls such as environmental, burial diagenesis, source rocks and climatic influences in the Muglad Sedimentary Basin. (author). 19 refs., 11 figs., 3 tabs

  15. Structure analysis of K3H(SO4)2 by neutron powder diffraction

    International Nuclear Information System (INIS)

    Murakami, Satoshi; Kuroiwa, Yoshihiro; Noda, Yukio; Nakai, Yusuke; Kamiyama, Takashi; Asano, Hajime.

    1993-01-01

    Neutron powder diffraction experiments of K 3 H(SO 4 ) 2 were carried out at KENS-HRP station in order to obtain the positional parameters of hydrogen nuclei. The data was taken at six different temperatures from room temperature to 20K. Even though K 3 H(SO 4 ) 2 contained a hydrogen atom, the structural analysis was successfully performed by using a program RIETAN. Concerning the hydrogen position, four different models give almost the same R-factor so that the state of the hydrogen nucleus is not uniquely determined. The result based on the assumption that a hydrogen nucleus occupies two sites shows that the distance of split hydrogen nuclei is shorter than the distance of hydrogen electron clouds. This result suggests that a large polarizability exists in a hydrogen atom. (author)

  16. The fit of an X-ray diffraction profile by Fourier analysis

    International Nuclear Information System (INIS)

    Bourniquel, B.; Feron, J.

    1985-01-01

    The fast Fourier transform algorithm commonly used for line profile analysis requires a list of values of the diffracted intensity with constant sintheta step; raw data are usually obtained at constant 2theta step; to interpolate between the measured values an analytic expression of the profile function is very useful. Statistical estimation is used to fit an analytic function to data; the only assumption made is the continuity of this function and no critical initialization is needed. Three different expressions are used: a Fourier sum for the peak and two polynomials of a suitable variable for the tails; the algorithm provides continuity for the function and its first derivative. Simulated examples using a Lorentzian and a Gaussian function are given and several criteria of goodness of fit are examined. The program runs on a PDP 11/03 digital computer with only 45 kbytes available memory. (orig.)

  17. X-Ray Diffraction for In-Situ Mineralogical Analysis of Planetesimals.

    Science.gov (United States)

    Sarrazin, P.; Blake, D. F.; Dera, P.; Downs, R. T.; Taylor, J.

    2017-12-01

    X-ray diffraction (XRD) is a general purpose technique for definitive, quantitative mineralogical analysis. When combined with XRF data for sample chemistry, XRD analyses yield as complete a characterization as is possible by any spacecraft-capable techniques. The MSL CheMin instrument, the first XRD instrument flown in space, has been used to establish the quantitative mineralogy of the Mars global soil, to discover the first habitable environment on another planet, and to provide the first in-situ evidence of silicic volcanism on Mars. CheMin is now used to characterize the depositional and diagenetic environments associated with the mudstone sediments of lower strata of Mt. Sharp. Conventional powder XRD requires samples comprised of small grains presented in random orientations. In CheMin, sample cells are vibrated to cause loose powder to flow within the cell, driven by granular convection, which relaxes the requirement for fine grained samples. Nevertheless, CheMin still requires mechanisms to collect, crush, sieve and deliver samples before analysis. XTRA (Extraterrestrial Regolith Analyzer) is an evolution of CheMin intended to analyze fines in as-delivered surface regolith, without sample preparation. Fine-grained regolith coats the surfaces of most airless bodies in the solar system, and because this fraction is typically comminuted from the rocky regolith, it can often be used as a proxy for the surface as a whole. HXRD (Hybrid-XRD) is concept under development to analyze rocks or soils without sample preparation. Like in CheMin, the diffracted signal is collected with direct illumination CCD's. If the material is sufficiently fine-grained, a powder XRD pattern of the characteristic X-ray tube emission is obtained, similar to CheMin or XTRA. With coarse grained crystals, the white bremsstrahlung radiation of the tube is diffracted into Laue patterns. Unlike typical Laue applications, HXRD uses the CCD's capability to distinguish energy and analyze the

  18. Big-data reflection high energy electron diffraction analysis for understanding epitaxial film growth processes.

    Science.gov (United States)

    Vasudevan, Rama K; Tselev, Alexander; Baddorf, Arthur P; Kalinin, Sergei V

    2014-10-28

    Reflection high energy electron diffraction (RHEED) has by now become a standard tool for in situ monitoring of film growth by pulsed laser deposition and molecular beam epitaxy. Yet despite the widespread adoption and wealth of information in RHEED images, most applications are limited to observing intensity oscillations of the specular spot, and much additional information on growth is discarded. With ease of data acquisition and increased computation speeds, statistical methods to rapidly mine the data set are now feasible. Here, we develop such an approach to the analysis of the fundamental growth processes through multivariate statistical analysis of a RHEED image sequence. This approach is illustrated for growth of La(x)Ca(1-x)MnO(3) films grown on etched (001) SrTiO(3) substrates, but is universal. The multivariate methods including principal component analysis and k-means clustering provide insight into the relevant behaviors, the timing and nature of a disordered to ordered growth change, and highlight statistically significant patterns. Fourier analysis yields the harmonic components of the signal and allows separation of the relevant components and baselines, isolating the asymmetric nature of the step density function and the transmission spots from the imperfect layer-by-layer (LBL) growth. These studies show the promise of big data approaches to obtaining more insight into film properties during and after epitaxial film growth. Furthermore, these studies open the pathway to use forward prediction methods to potentially allow significantly more control over growth process and hence final film quality.

  19. X-ray diffraction and thermal analysis of kaolins particle size fractions

    Directory of Open Access Journals (Sweden)

    Patricia dos Santos

    2013-09-01

    Full Text Available Kaolins are common geological materials and have high concentrations of kaolinite as well as the clay fraction of tropical and subtropical soils of Brazil. The characterization of kaolin is a proxy of assessing the contribution of kaolinite to important soil chemical and mineralogical attributes. This study evaluated four kaolins (commercial kaolin A (CCA, commercial kaolin B (CCB, pink sandy kaolin A (CRA and green sandy kaolin A (CVA in the original form and after particle size separation into: sand (200-53 mm, coarse silt (53-20 m, fine silt (20-2 m, large clay (2-1m, medium clay (1-0.5 m and fine clay (<0.5m fractions. The minerals were identified by X-ray diffraction (XRD and evaluated for crystallinity (kaolinite and halloysite through indexes Hughes and Brown, Amigó, Bramão and the dehydroxylation temperature. The physical fractionation was efficient to concentrate minerals in specific size fractions which were not identified in the original material. In CCA kaolin was concentrated one mineral which remains unidentified in fine fractions, in kaolin CRA, zircon was concentrated in the coarse silt and different silicates in the fine fractions, in kaolin CCB were concentrated kaolinite and a silicate in the medium and coarse clay fractions. The estimate by X-ray diffraction overestimated the amount of kaolinite and halloysite underestimated when compared to quantification by thermal gravimetric analysis The crystallinity index exhibit different behaviors depending on the mineralogy of each material, thus the correlation between the crystallinity of kaolinite and / or halloysite and other variables, may be compromised, especially in materials with distinct geological origins.

  20. Analysis of strain error sources in micro-beam Laue diffraction

    International Nuclear Information System (INIS)

    Hofmann, Felix; Eve, Sophie; Belnoue, Jonathan; Micha, Jean-Sébastien; Korsunsky, Alexander M.

    2011-01-01

    Micro-beam Laue diffraction is an experimental method that allows the measurement of local lattice orientation and elastic strain within individual grains of engineering alloys, ceramics, and other polycrystalline materials. Unlike other analytical techniques, e.g. based on electron microscopy, it is not limited to surface characterisation or thin sections, but rather allows non-destructive measurements in the material bulk. This is of particular importance for in situ loading experiments where the mechanical response of a material volume (rather than just surface) is studied and it is vital that no perturbation/disturbance is introduced by the measurement technique. Whilst the technique allows lattice orientation to be determined to a high level of precision, accurate measurement of elastic strains and estimating the errors involved is a significant challenge. We propose a simulation-based approach to assess the elastic strain errors that arise from geometrical perturbations of the experimental setup. Using an empirical combination rule, the contributions of different geometrical uncertainties to the overall experimental strain error are estimated. This approach was applied to the micro-beam Laue diffraction setup at beamline BM32 at the European Synchrotron Radiation Facility (ESRF). Using a highly perfect germanium single crystal, the mechanical stability of the instrument was determined and hence the expected strain errors predicted. Comparison with the actual strain errors found in a silicon four-point beam bending test showed good agreement. The simulation-based error analysis approach makes it possible to understand the origins of the experimental strain errors and thus allows a directed improvement of the experimental geometry to maximise the benefit in terms of strain accuracy.

  1. Study on the microstructure of recycled zircaloy by X-ray diffraction line profile analysis

    International Nuclear Information System (INIS)

    Ichikawa, Rodrigo U.; Pereira, Luiz A.T.; Imakuma, Kengo; Martinez, Luis G.; Turrillas, Xavier

    2013-01-01

    In the fabrication of nuclear fuel elements parts, Zircaloy machining chips are generated and, as this material is high-valued and controlled, its recycling presents high interest not only in economic aspects but also for environmental reasons and due to its strategic role in nuclear technology. Two processes for the recovery of these Zircaloy chips are being studied at IPEN-CNEN/SP. One of the processes is by conventional remelting of the material in a VAR (Vacuum Arc Remelting) furnace for producing solid ingots. Concurrently it is being studied an alternative process, by powder metallurgy methods, by which the chips are hydrided in order to become brittle and be grinded. The resulting ground powder is then compacted and finally vacuum-dehydrided and sintered in one step to form solid pieces. The VAR-remelted samples were also submitted to heat treatments in order to refine their microstructures, resulting in three different samples named 'as cast', 'annealed' and 'tempered'. The microstructures resulting from both processes and also from heat treatments were studied by metallography and X-ray diffraction (XRD). In this work, results of a XRD study are presented applying X-ray diffraction Line Profile Analysis (XLPA) methods in order to determine the mean crystallite sizes and the RMS microstrains on these samples. Additionally, a study for verify the influence of different standard materials used for the correction of the instrumental breadth in the XLPA was developed. The XLPA results show the influence of the processes and also of heat treatments on mean crystallite sizes and microstrains of the samples and were compared to their metallographic study and hardness. (author)

  2. FEM Analysis and Measurement of Residual Stress by Neutron Diffraction on the Dissimilar Overlay Weld Pipe

    International Nuclear Information System (INIS)

    Kim, Kang Soo; Lee, Ho Jin; Woo, Wan Chuck; Seong, Baek Seok; Byeon, Jin Gwi; Park, Kwang Soo; Jung, In Chul

    2010-01-01

    Much research has been done to estimate the residual stress on a dissimilar metal weld. There are many methods to estimate the weld residual stress and FEM (Finite Element Method) is generally used due to the advantage of the parametric study. And the X-ray method and a Hole Drilling technique for an experimental method are also usually used. The aim of this paper is to develop the appropriate FEM model to estimate the residual stresses of the dissimilar overlay weld pipe. For this, firstly, the specimen of the dissimilar overlay weld pipe was manufactured. The SA 508 Gr3 nozzle, the SA 182 safe end and SA376 pipe were welded by the Alloy 182. And the overlay weld by the Alloy 52M was performed. The residual stress of this specimen was measured by using the Neutron Diffraction device in the HANARO (High-flux Advanced Neutron Application ReactOr) research reactor, KAERI (Korea Atomic Energy Research Institute). Secondly, FEM Model on the dissimilar overlay weld pipe was made and analyzed by the ABAQUS Code (ABAQUS, 2004). Thermal analysis and stress analysis were performed, and the residual stress was calculated. Thirdly, the results of the FEM analysis were compared with those of the experimental methods

  3. Diffractive interactions

    International Nuclear Information System (INIS)

    Del Duca, V.; Marage, P.

    1996-08-01

    The general framework of diffractive deep inelastic scattering is introduced and reports given in the session on diffractive interactions at the international workshop on deep-inelastic scattering and related phenomena, Rome, April 1996, are presented. (orig.)

  4. Diffraction theory

    NARCIS (Netherlands)

    Bouwkamp, C.J.

    1954-01-01

    A critical review is presented of recent progress in classical diffraction theory. Both scalar and electromagnetic problems are discussed. The report may serve as an introduction to general diffraction theory although the main emphasis is on diffraction by plane obstacles. Various modifications of

  5. Validation of the method of quantitative phase analysis by X-ray diffraction in API: case of Tibolone

    International Nuclear Information System (INIS)

    Silva, R P; Ambrósio, M F S; Epprecht, E K; Avillez, R R; Achete, C A; Kuznetsov, A; Visentin, L C

    2016-01-01

    In this study, different structural and microstructural models applied to X-ray analysis of powder diffraction data of polymorphic mixtures of known concentrations of Tibolone were investigated. The X-ray data obtained in different diffraction instruments were analysed via Rietveld method using the same analytical models. The results of quantitative phase analysis show that regardless of the instrument used, the values of the calculated concentrations follow the same systematics with respect to the final errors. The strategy to select a specific analytical model that leads to lower measurement errors is here presented. (paper)

  6. Proton diffraction

    International Nuclear Information System (INIS)

    Den Besten, J.L.; Jamieson, D.N.; Allen, L.J.

    1998-01-01

    The Lindhard theory on ion channeling in crystals has been widely accepted throughout ion beam analysis for use in simulating such experiments. The simulations use a Monte Carlo method developed by Barret, which utilises the classical 'billiard ball' theory of ions 'bouncing' between planes or tubes of atoms in the crystal. This theory is not valid for 'thin' crystals where the planes or strings of atoms can no longer be assumed to be of infinite proportions. We propose that a theory similar to that used for high energy electron diffraction can be applied to MeV ions, especially protons, in thin crystals to simulate the intensities of transmission channeling and of RBS spectra. The diffraction theory is based on a Bloch wave solution of the Schroedinger equation for an ion passing through the periodic crystal potential. The widely used universal potential for proton-nucleus scattering is used to construct the crystal potential. Absorption due to thermal diffuse scattering is included. Experimental parameters such as convergence angle, beam tilt and scanning directions are considered in our calculations. Comparison between theory and experiment is encouraging and suggests that further work is justified. (authors)

  7. A high-transparency, micro-patternable chip for X-ray diffraction analysis of microcrystals under native growth conditions

    Energy Technology Data Exchange (ETDEWEB)

    Murray, Thomas D. [University of California, Berkeley, CA 94720 (United States); Johns Hopkins University School of Medicine, Baltimore, MD 21205 (United States); Lyubimov, Artem Y. [Stanford University, Stanford, CA 94305 (United States); Ogata, Craig M. [Argonne National Laboratory, Argonne, IL 60439 (United States); Vo, Huy [Johns Hopkins University, Baltimore, MD 21205 (United States); Uervirojnangkoorn, Monarin; Brunger, Axel T., E-mail: brunger@stanford.edu [Stanford University, Stanford, CA 94305 (United States); Berger, James M., E-mail: brunger@stanford.edu [Johns Hopkins University School of Medicine, Baltimore, MD 21205 (United States); University of California, Berkeley, CA 94720 (United States)

    2015-09-26

    A highly X-ray-transparent, silicon nitride-based device has been designed and fabricated to harvest protein microcrystals for high-resolution X-ray diffraction data collection using microfocus beamlines and XFELs. Microcrystals present a significant impediment to the determination of macromolecular structures by X-ray diffraction methods. Although microfocus synchrotron beamlines and X-ray free-electron lasers (XFELs) can enable the collection of interpretable diffraction data from microcrystals, there is a need for efficient methods of harvesting small volumes (<2 µl) of microcrystals grown under common laboratory formats and delivering them to an X-ray beam source under native growth conditions. One approach that shows promise in overcoming the challenges intrinsic to microcrystal analysis is to pair so-called ‘fixed-target’ sample-delivery devices with microbeam-based X-ray diffraction methods. However, to record weak diffraction patterns it is necessary to fabricate devices from X-ray-transparent materials that minimize background scattering. Presented here is the design of a new micro-diffraction device consisting of three layers fabricated from silicon nitride, photoresist and polyimide film. The chip features low X-ray scattering and X-ray absorption properties, and uses a customizable blend of hydrophobic and hydrophilic surface patterns to help localize microcrystals to defined regions. Microcrystals in their native growth conditions can be loaded into the chips with a standard pipette, allowing data collection at room temperature. Diffraction data collected from hen egg-white lysozyme microcrystals (10–15 µm) loaded into the chips yielded a complete, high-resolution (<1.6 Å) data set sufficient to determine a high-quality structure by molecular replacement. The features of the chip allow the rapid and user-friendly analysis of microcrystals grown under virtually any laboratory format at microfocus synchrotron beamlines and XFELs.

  8. A high-transparency, micro-patternable chip for X-ray diffraction analysis of microcrystals under native growth conditions

    International Nuclear Information System (INIS)

    Murray, Thomas D.; Lyubimov, Artem Y.; Ogata, Craig M.; Vo, Huy; Uervirojnangkoorn, Monarin; Brunger, Axel T.; Berger, James M.

    2015-01-01

    A highly X-ray-transparent, silicon nitride-based device has been designed and fabricated to harvest protein microcrystals for high-resolution X-ray diffraction data collection using microfocus beamlines and XFELs. Microcrystals present a significant impediment to the determination of macromolecular structures by X-ray diffraction methods. Although microfocus synchrotron beamlines and X-ray free-electron lasers (XFELs) can enable the collection of interpretable diffraction data from microcrystals, there is a need for efficient methods of harvesting small volumes (<2 µl) of microcrystals grown under common laboratory formats and delivering them to an X-ray beam source under native growth conditions. One approach that shows promise in overcoming the challenges intrinsic to microcrystal analysis is to pair so-called ‘fixed-target’ sample-delivery devices with microbeam-based X-ray diffraction methods. However, to record weak diffraction patterns it is necessary to fabricate devices from X-ray-transparent materials that minimize background scattering. Presented here is the design of a new micro-diffraction device consisting of three layers fabricated from silicon nitride, photoresist and polyimide film. The chip features low X-ray scattering and X-ray absorption properties, and uses a customizable blend of hydrophobic and hydrophilic surface patterns to help localize microcrystals to defined regions. Microcrystals in their native growth conditions can be loaded into the chips with a standard pipette, allowing data collection at room temperature. Diffraction data collected from hen egg-white lysozyme microcrystals (10–15 µm) loaded into the chips yielded a complete, high-resolution (<1.6 Å) data set sufficient to determine a high-quality structure by molecular replacement. The features of the chip allow the rapid and user-friendly analysis of microcrystals grown under virtually any laboratory format at microfocus synchrotron beamlines and XFELs

  9. Semiconductor Quantum Electron Wave Transport, Diffraction, and Interference: Analysis, Device, and Measurement.

    Science.gov (United States)

    Henderson, Gregory Newell

    Semiconductor device dimensions are rapidly approaching a fundamental limit where drift-diffusion equations and the depletion approximation are no longer valid. In this regime, quantum effects can dominate device response. To increase further device density and speed, new devices must be designed that use these phenomena to positive advantage. In addition, quantum effects provide opportunities for a new class of devices which can perform functions previously unattainable with "conventional" semiconductor devices. This thesis has described research in the analysis of electron wave effects in semiconductors and the development of methods for the design, fabrication, and characterization of quantum devices based on these effects. First, an exact set of quantitative analogies are presented which allow the use of well understood optical design and analysis tools for the development of electron wave semiconductor devices. Motivated by these analogies, methods are presented for modeling electron wave grating diffraction using both an exact rigorous coupled-wave analysis and approximate analyses which are useful for grating design. Example electron wave grating switch and multiplexer designs are presented. In analogy to thin-film optics, the design and analysis of electron wave Fabry-Perot interference filters are also discussed. An innovative technique has been developed for testing these (and other) electron wave structures using Ballistic Electron Emission Microscopy (BEEM). This technique uses a liquid-helium temperature scanning tunneling microscope (STM) to perform spectroscopy of the electron transmittance as a function of electron energy. Experimental results show that BEEM can resolve even weak quantum effects, such as the reflectivity of a single interface between materials. Finally, methods are discussed for incorporating asymmetric electron wave Fabry-Perot filters into optoelectronic devices. Theoretical and experimental results show that such structures could

  10. Analysis of the diffraction peaks in the ZrCr2 system

    International Nuclear Information System (INIS)

    Quiroga, A.A.; Esquivel, M.R.

    2009-01-01

    In this work, the crystalline structures of Cr and Zr are characterized by X-ray Diffraction (XRD). The diffraction peaks are simulated using a numerical convolution of the Gauss and Lorentz functions. The simulation of the model is verified using empirical measurements of the diffraction peaks. From these results, the microstructure parameters of Zr and Cr are obtained: crystallite size (d) and strain (s). The advances obtained are used in the design of the synthesis of AB 2 intermetallics applied to thermal compression of hydrogen (Tch). (author)

  11. Crystallization, diffraction data collection and preliminary crystallographic analysis of DING protein from Pseudomonas fluorescens

    International Nuclear Information System (INIS)

    Moniot, Sebastien; Elias, Mikael; Kim, Donghyo; Scott, Ken; Chabriere, Eric

    2007-01-01

    Crystallization of DING protein from P. fluorescens is reported. A complete data set was collected to 1.43 Å resolution. PfluDING is a phosphate-binding protein expressed in Pseudomonas fluorescens. This protein is clearly distinct from the bacterial ABC transporter soluble phosphate-binding protein PstS and is more homologous to eukaryotic DING proteins. Interestingly, bacterial DING proteins have only been detected in certain Pseudomonas species. Although DING proteins seem to be ubiquitous in eukaryotes, they are systematically absent from eukaryotic genomic databases and thus are still quite mysterious and poorly characterized. PfluDING displays mitogenic activity towards human cells and binds various ligands such as inorganic phosphate, pyrophosphate, nucleotide triphosphates and cotinine. Here, the crystallization of PfluDING is reported in a monoclinic space group (P2 1 ), with typical unit-cell parameters a = 36.7, b = 123.7, c = 40.8 Å, α = 90, β = 116.7, γ = 90°. Preliminary crystallographic analysis reveals good diffraction quality for these crystals and a 1.43 Å resolution data set has been collected

  12. Residual stress analysis for engineering applications by means of neutron diffraction

    International Nuclear Information System (INIS)

    Gnaeupel-Herold, T.; Brand, P.C.; Prask, H.J.

    1999-01-01

    Residual stresses originate from spatial differences in plastic deformation, temperature, or phase distribution, introduced by manufacturing processes or during service. Engineering parts and materials experience mechanical, thermal, and chemical loads during their service, and most of these loads introduce stresses that are superimposed on the already existing residual stresses. Residual stresses can therefore limit or improve life and strength of engineering parts; knowledge and understanding of these stresses is therefore critical for optimizing strength and durability. The economic and scientific importance of neutron diffraction residual stress analysis has led to an increasing number of suitable instruments worldwide. All of the major sources due in the next several years will have instruments for the sole purpose of performing residual stress and texture measurements. Recently, a dedicated, state-of-the-art diffractometer has been installed at the National Institute of Standards and Technology reactor. It has been used for a variety of measurements on basic and engineering stress problems. Among the most prominent examples that have been investigated in collaboration with industrial and academic partners are residual stresses in rails, weldments, and plasma-sprayed coatings

  13. Analysis of dislocation loops by means of large-angle convergent beam electron diffraction

    International Nuclear Information System (INIS)

    Jaeger, Ch; Spiecker, E; Morniroli, J P; Jaeger, W

    2002-01-01

    Diffusion-induced dislocation loops in GaP and GaAs were analysed by means of large-angle convergent beam electron diffraction (LACBED) and conventional contrast methods of transmission electron microscopy. It is demonstrated that LACBED is perfectly suited for use in analysing dislocation loops. The method combines analyses of the dislocation-induced splitting of Bragg lines in a LACBED pattern for the determination of the Burgers vector with analyses of the loop contrast behaviour in transmission electron microscopy bright-field images during tilt experiments, from which the habit plane of the dislocation loop is determined. Perfect dislocation loops formed by condensation of interstitial atoms or vacancies were found, depending on the diffusion conditions. The loops possess {110}-habit planes and Burgers vectors parallel to (110). The LACBED method findings are compared with results of contrast analyses based on the so-called 'inside-outside' contrast of dislocation loops. Advantages of the LACBED method consist in the possibility of determining the complete Burgers vector of the dislocation loops and of an unambiguous and fast loop type analysis

  14. Production of muscovite-feldspathic glass composite: scanning electron microscopy and X-ray diffraction analysis

    International Nuclear Information System (INIS)

    Costa, F.P.F.; Ogasawara, T.; Santos, S.F.

    2009-01-01

    The objective of this work was to find the sintering conditions for the feldspathic glass + muscovite mixture to produce a dense composite block for manufacturing dental prosthesis by using CAD-CAM. Each 20g of the glass-frit had : 15.55g of Armil-feldspar; 0.53g of Al 2 O 3 ; 1.56g of Na 2 CO 3 ; 0.5g of borax; 1.74g of K 2 CO 3 ; 0.13g of CeO 2 . Frit's powder finer than 350 Tyler mesh was mixed with 0 wt%, 10 wt%, 20 wt% and 100 wt% of muscovite pressed cylinders (5600 pounds force) 16mm in diameter and sintered under vacuum Vacumat (VITA) furnace at 850 deg C, 900 deg C, 950 deg C, 1000 deg C, 1050 deg C, 1100 deg C and 1150 deg C. X-ray diffraction analysis and scanning electron microscopy were carried out. The necessary temperature for high densification depended on the composition of the mixture: 850 deg C (for pure frit); 1050 deg C (for 10 wt% mica) and 1150 deg C (for 20 wt% mica); pure mica degraded during sintering. (author)

  15. Overproduction, purification, crystallization and preliminary X-ray diffraction analysis of Trypanosoma brucei gambiense glycerol kinase

    International Nuclear Information System (INIS)

    Balogun, Emmanuel Oluwadare; Inaoka, Daniel Ken; Kido, Yasutoshi; Shiba, Tomoo; Nara, Takeshi; Aoki, Takashi; Honma, Teruki; Tanaka, Akiko; Inoue, Masayuki; Matsuoka, Shigeru; Michels, Paul A. M.; Harada, Shigeharu; Kita, Kiyoshi

    2010-01-01

    Glycerol kinase from human African trypanosomes has been purified and crystallized for X-ray structure analysis. In the bloodstream forms of human trypanosomes, glycerol kinase (GK; EC 2.7.1.30) is one of the nine glycosomally compartmentalized enzymes that are essential for energy metabolism. In this study, a recombinant Trypanosoma brucei gambiense GK (rTbgGK) with an N-terminal cleavable His 6 tag was overexpressed, purified to homogeneity and crystallized by the sitting-drop vapour-diffusion method using PEG 400 as a precipitant. A complete X-ray diffraction data set to 2.75 Å resolution indicated that the crystals belonged to the orthorhombic space group P2 1 2 1 2 1 , with unit-cell parameters a = 63.84, b = 121.50, c = 154.59 Å. The presence of two rTbgGK molecules in the asymmetric unit gives a Matthews coefficient (V M ) of 2.5 Å 3 Da −1 , corresponding to 50% solvent content

  16. Analysis of neutron diffraction peak broadening caused by internal stresses in composite materials

    International Nuclear Information System (INIS)

    Todd, R.I.; Borsa, C.; Derby, B.

    1994-01-01

    Neutron diffraction is an essential tool in the study of internal stresses in composite materials. In most work only the peak shifts caused by the related elastic strains are considered, but other valuable information exists in the form of peak shape changes. The conditions under which the pure diffraction profile of the composite (i.e. the profile when all sources of broadening not caused by the residual stresses are removed) represents the probability distribution of the peak shifts corresponding to the strains are examined. It is shown that in these conditions, the pure diffraction profile has no attributes of particle size broadening (and vice versa), thereby providing a test for the validity of results interpreted in this way. The experimental derivation of measured strain distributions in Al 2 O 3 /SiCp composites using neutron diffraction is described. No apparent particle size broadening was detected, demonstrating the validity of the results, which also satisfied other tests for consistency

  17. An Inquiry-Based Project Focused on the X-Ray Powder Diffraction Analysis of Common Household Solids

    Science.gov (United States)

    Hulien, Molly L.; Lekse, Jonathan W.; Rosmus, Kimberly A.; Devlin, Kasey P.; Glenn, Jennifer R.; Wisneski, Stephen D.; Wildfong, Peter; Lake, Charles H.; MacNeil, Joseph H.; Aitken, Jennifer A.

    2015-01-01

    While X-ray powder diffraction (XRPD) is a fundamental analytical technique used by solid-state laboratories across a breadth of disciplines, it is still underrepresented in most undergraduate curricula. In this work, we incorporate XRPD analysis into an inquiry-based project that requires students to identify the crystalline component(s) of…

  18. Examples of neutron diffraction texture analysis on one and the same chalcopyrite sample before and after experimental deformation

    International Nuclear Information System (INIS)

    Jansen, E.M.; Brokmeier, H.G.; Siemes, H.

    1994-01-01

    Natural chalcopyrite specimens from Mt. Isa, Australia were investigated by neutron diffraction texture analysis. The preferred orientation of the specimens consists of 3 main orientation components. After axial shortening at a temperature of 25 C the initial orientation components became weaker, a new component was detected. (orig.)

  19. Non-destructive bulk analysis of the Buggenum sword by neutron resonance capture analysis and neutron diffraction

    International Nuclear Information System (INIS)

    Postma, H.; Clarijs, M.; Borella, A.; Schillebeeckx, P.; Kamermans, H.

    2010-01-01

    Two neutron based techniques, neutron resonance capture analysis (NRCA) and time-of-flight neutron-diffraction (TOF-ND) have been used to determine the elemental composition and structure of a precious and very well preserved all-metal sword from the Bronze Age. This Buggenum sword was on loan from the National Museum of Antiquities (NMA) in Leiden (NL). NRCA and TOF-ND experiments have been carried out at a number of more or less identical positions of the sword. The tin-bronze ratio and the relative amounts of some minor elements (Sb, As, Ag, In) have been determined. The results of neutron diffraction measurements showed considerable tin-segregation, and clear indications of hardening on the edges of the blade. In addition, radiographs using Bremsstrahlung revealed the construction of the hilt-blade connection. The work was carried out at the EC Joint Research Centre IRMM in Geel (B) and at the ISIS facility of the Rutherford Appleton Laboratory (UK). (author)

  20. Phase analysis of nano-phase materials using selected area electron diffraction in the TEM

    International Nuclear Information System (INIS)

    Labar, J. L.

    2002-01-01

    In analogy to X-ray power diffraction (XRD), we are developing a method to help phase identification when examining a large number of grains simultaneously by electron diffraction. Although XRD is well established, it can not be used for small quantities of materials (volumes below 1 mm 3 ). Examining a usual TEM sample with thickness of 100 nm and using a selected area of 1 mm in diameter, the selected area electron diffraction pattern (SAED) carries information about several thousands of grains from a material with an average grain size of about 10 nm. The accuracy of XRD can not be attained by electron diffraction (ED). However, simultaneous visual observation of the nanostructure is an additional benefit of TEM (beside the small amount of needed material). The first step of the development project was the development of a computer program ('ProcessDiffraction') that processes digital versions of SAED patterns and presents them in an XRD-like form (intensity vs. scattering vector). In the present version (V2.0.3) phase identification is carried out by comparing the measured distribution to 'Markers', i.e. data of known phases. XRD data cards are used if the detailed structure of a phase is not known. Kinematic electron diffraction intensities are calculated for phases with known atomic positions (Author)

  1. Steel research using neutron beam techniques. In-situ neutron diffraction, small-angle neutron scattering and residual stress analysis

    International Nuclear Information System (INIS)

    Sueyoshi, Hitoshi; Ishikawa, Nobuyuki; Yamada, Katsumi; Sato, Kaoru; Nakagaito, Tatsuya; Matsuda, Hiroshi; Arakaki, Yu; Tomota, Yo

    2014-01-01

    Recently, the neutron beam techniques have been applied for steel researches and industrial applications. In particular, the neutron diffraction is a powerful non-destructive method that can analyze phase transformation and residual stress inside the steel. The small-angle neutron scattering is also an effective method for the quantitative evaluation of microstructures inside the steel. In this study, in-situ neutron diffraction measurements during tensile test and heat treatment were conducted in order to investigate the deformation and transformation behaviors of TRIP steels. The small-angle neutron scattering measurements of TRIP steels were also conducted. Then, the neutron diffraction analysis was conducted on the high strength steel weld joint in order to investigate the effect of the residual stress distribution on the weld cracking. (author)

  2. Diffraction at TOTEM

    OpenAIRE

    Giani, S; Niewiadomski, H; Antchev, G; Aspell, P; Avati, V; Bagliesi, M G; Berardi, V; Berretti, M; Besta, M; Bozzo, M; Brücken, E; Buzzo, A; Cafagna, F; Calicchio, M; Catanesi, M G

    2010-01-01

    The primary objective of the TOTEM experiment at the LHC is the measurement of the total proton-proton cross section with the luminosity-independent method and the study of elastic proton-proton cross-section over a wide |t|-range. In addition TOTEM also performs a comprehensive study of diffraction, spanning from cross-section measurements of individual diffractive processes to the analysis of their event topologies. Hard diffraction will be studied in collaboration with CMS taking advantage...

  3. Diffraction at TOTEM

    OpenAIRE

    Antchev, G.; Aspell, P.; Avati, V.; Bagliesi, M.G.; Berardi, V.; Berretti, M.; Bottigli, U.; Bozzo, M.; Brucken, E.; Buzzo, A.; Cafagna, F.; Calicchio, M.; Catanesi, M.G.; Catastini, P.L.; Cecchi, R.

    2008-01-01

    The TOTEM experiment at the LHC measures the total proton-proton cross section with the luminosity-independent method and the elastic proton-proton cross-section over a wide |t|-range. It also performs a comprehensive study of diffraction, spanning from cross-section measurements of individual diffractive processes to the analysis of their event topologies. Hard diffraction will be studied in collaboration with CMS taking advantage of the large common rapidity coverage for charged and neutral...

  4. Diffraction-based analysis of tunnel size for a scaled external occulter testbed

    Science.gov (United States)

    Sirbu, Dan; Kasdin, N. Jeremy; Vanderbei, Robert J.

    2016-07-01

    For performance verification of an external occulter mask (also called a starshade), scaled testbeds have been developed to measure the suppression of the occulter shadow in the pupil plane and contrast in the image plane. For occulter experiments the scaling is typically performed by maintaining an equivalent Fresnel number. The original Princeton occulter testbed was oversized with respect to both input beam and shadow propagation to limit any diffraction effects due to finite testbed enclosure edges; however, to operate at realistic space-mission equivalent Fresnel numbers an extended testbed is currently under construction. With the longer propagation distances involved, diffraction effects due to the edge of the tunnel must now be considered in the experiment design. Here, we present a diffraction-based model of two separate tunnel effects. First, we consider the effect of tunnel-edge induced diffraction ringing upstream from the occulter mask. Second, we consider the diffraction effect due to clipping of the output shadow by the tunnel downstream from the occulter mask. These calculations are performed for a representative point design relevant to the new Princeton occulter experiment, but we also present an analytical relation that can be used for other propagation distances.

  5. Novel design and sensitivity analysis of displacement measurement system utilizing knife edge diffraction for nanopositioning stages.

    Science.gov (United States)

    Lee, ChaBum; Lee, Sun-Kyu; Tarbutton, Joshua A

    2014-09-01

    This paper presents a novel design and sensitivity analysis of a knife edge-based optical displacement sensor that can be embedded with nanopositioning stages. The measurement system consists of a laser, two knife edge locations, two photodetectors, and axillary optics components in a simple configuration. The knife edge is installed on the stage parallel to its moving direction and two separated laser beams are incident on knife edges. While the stage is in motion, the direct transverse and diffracted light at each knife edge is superposed producing interference at the detector. The interference is measured with two photodetectors in a differential amplification configuration. The performance of the proposed sensor was mathematically modeled, and the effect of the optical and mechanical parameters, wavelength, beam diameter, distances from laser to knife edge to photodetector, and knife edge topography, on sensor outputs was investigated to obtain a novel analytical method to predict linearity and sensitivity. From the model, all parameters except for the beam diameter have a significant influence on measurement range and sensitivity of the proposed sensing system. To validate the model, two types of knife edges with different edge topography were used for the experiment. By utilizing a shorter wavelength, smaller sensor distance and higher edge quality increased measurement sensitivity can be obtained. The model was experimentally validated and the results showed a good agreement with the theoretically estimated results. This sensor is expected to be easily implemented into nanopositioning stage applications at a low cost and mathematical model introduced here can be used for design and performance estimation of the knife edge-based sensor as a tool.

  6. Production, crystallization and preliminary X-ray diffraction analysis of the allergen Can f 2 from Canis familiaris

    International Nuclear Information System (INIS)

    Madhurantakam, Chaithanya; Nilsson, Ola B.; Jönsson, Klas; Grönlund, Hans; Achour, Adnane

    2009-01-01

    The recombinant form of the allergen Can f 2 from C. familiaris was produced, isolated and crystallized in two different forms. Preliminary X-ray diffraction analyses are reported for the two crystal forms of Can f 2. The allergen Can f 2 from dog (Canis familiaris) present in saliva, dander and fur is an important cause of allergic sensitization worldwide. Here, the production, isolation, crystallization and preliminary X-ray diffraction analysis of two crystal forms of recombinant Can f 2 are reported. The first crystal form belonged to space group C222, with unit-cell parameters a = 68.7, b = 77.3, c = 65.1 Å, and diffracted to 1.55 Å resolution, while the second crystal form belonged to space group C2, with unit-cell parameters a = 75.7, b = 48.3, c = 68.7 Å, β = 126.5°, and diffracted to 2.1 Å resolution. Preliminary data analysis indicated the presence of a single molecule in the asymmetric unit for both crystal forms

  7. Digital diffraction analysis enables low-cost molecular diagnostics on a smartphone.

    Science.gov (United States)

    Im, Hyungsoon; Castro, Cesar M; Shao, Huilin; Liong, Monty; Song, Jun; Pathania, Divya; Fexon, Lioubov; Min, Changwook; Avila-Wallace, Maria; Zurkiya, Omar; Rho, Junsung; Magaoay, Brady; Tambouret, Rosemary H; Pivovarov, Misha; Weissleder, Ralph; Lee, Hakho

    2015-05-05

    The widespread distribution of smartphones, with their integrated sensors and communication capabilities, makes them an ideal platform for point-of-care (POC) diagnosis, especially in resource-limited settings. Molecular diagnostics, however, have been difficult to implement in smartphones. We herein report a diffraction-based approach that enables molecular and cellular diagnostics. The D3 (digital diffraction diagnosis) system uses microbeads to generate unique diffraction patterns which can be acquired by smartphones and processed by a remote server. We applied the D3 platform to screen for precancerous or cancerous cells in cervical specimens and to detect human papillomavirus (HPV) DNA. The D3 assay generated readouts within 45 min and showed excellent agreement with gold-standard pathology or HPV testing, respectively. This approach could have favorable global health applications where medical access is limited or when pathology bottlenecks challenge prompt diagnostic readouts.

  8. IOTA: integration optimization, triage and analysis tool for the processing of XFEL diffraction images.

    Science.gov (United States)

    Lyubimov, Artem Y; Uervirojnangkoorn, Monarin; Zeldin, Oliver B; Brewster, Aaron S; Murray, Thomas D; Sauter, Nicholas K; Berger, James M; Weis, William I; Brunger, Axel T

    2016-06-01

    Serial femtosecond crystallography (SFX) uses an X-ray free-electron laser to extract diffraction data from crystals not amenable to conventional X-ray light sources owing to their small size or radiation sensitivity. However, a limitation of SFX is the high variability of the diffraction images that are obtained. As a result, it is often difficult to determine optimal indexing and integration parameters for the individual diffraction images. Presented here is a software package, called IOTA , which uses a grid-search technique to determine optimal spot-finding parameters that can in turn affect the success of indexing and the quality of integration on an image-by-image basis. Integration results can be filtered using a priori information about the Bravais lattice and unit-cell dimensions and analyzed for unit-cell isomorphism, facilitating an improvement in subsequent data-processing steps.

  9. Initial idea to use optical flats for x-ray fluorescence analysis and recent applications to diffraction studies

    International Nuclear Information System (INIS)

    Horiuchi, T.

    1993-01-01

    Described in this work is the initial idea of using an optical flat for X-ray fluorescence analysis based upon studies of anomalous surface reflection (ASR). To develop total-reflection X-ray fluorescence analysis (TXRF) as one of the most powerful tools for microchemical analysis, various experiments such as the micro-determinations of uranium in sea-water, iron in human blood and rare earth elements in hot spring-water were attempted. Furthermore, the physically interesting experiment on Compton scattering under total-reflection conditions was conducted. Recent applications of the total-reflection phenomenon to diffraction studies, i.e. total-reflection X-ray diffraction (TXRD), are also presented. (author)

  10. Non-destructive Quantitative Phase Analysis and Microstructural Characterization of Zirconium Coated U-10Mo Fuel Foils via Neutron Diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Cummins, Dustin Ray [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Vogel, Sven C. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Hollis, Kendall Jon [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Brown, Donald William [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Dombrowski, David E. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-10-18

    This report uses neutron diffraction to investigate the crystal phase composition of uranium-molybdenum alloy foils (U-10Mo) for the CONVERT MP-1 Reactor Conversion Project, and determines the effect on alpha-uranium contamination following the deposition of a Zr metal diffusion layer by various methods: plasma spray deposition of Zr powders at LANL and hot co-rolling with Zr foils at BWXT. In summary, there is minimal decomposition of the gamma phase U-10Mo foil to alpha phase contamination following both plasma spraying and hot co-rolling. The average unit cell volume, i.e. lattice spacing, of the Zr layer can be mathematically extracted from the diffraction data; co-rolled Zr matches well with literature values of bulk Zr, while plasma sprayed Zr shows a slight increase in the lattice spacing, indicative of interstitial oxygen in the lattice. Neutron diffraction is a beneficial alternative to conventional methods of phase composition, i.e. x ray diffraction (XRD) and destructive metallography. XRD has minimal penetration depth in high atomic number materials, particularly uranium, and can only probe the first few microns of the fuel plate; neutrons pass completely through the foil, allowing for bulk analysis of the foil composition and no issues with addition of cladding layers, as in the final, aluminum-clad reactor fuel plates. Destructive metallography requires skilled technicians, cutting of the foil into small sections, hazardous etching conditions, long polishing and microscopy times, etc.; the neutron diffraction system has an automated sample loader and can fit larger foils, so there is minimal analysis preparation; the total spectrum acquisition time is ~ 1 hour per sample. The neutron diffraction results are limited by spectra refinement/calculation times and the availability of the neutron beam source. In the case of LANSCE at Los Alamos, the beam operates ~50% of the year. Following the lessons learned from these preliminary results, optimizations to

  11. Non-destructive Quantitative Phase Analysis and Microstructural Characterization of Zirconium Coated U-10Mo Fuel Foils via Neutron Diffraction

    International Nuclear Information System (INIS)

    Cummins, Dustin Ray; Vogel, Sven C.; Hollis, Kendall Jon; Brown, Donald William; Dombrowski, David E.

    2016-01-01

    This report uses neutron diffraction to investigate the crystal phase composition of uranium-molybdenum alloy foils (U-10Mo) for the CONVERT MP-1 Reactor Conversion Project, and determines the effect on alpha-uranium contamination following the deposition of a Zr metal diffusion layer by various methods: plasma spray deposition of Zr powders at LANL and hot co-rolling with Zr foils at BWXT. In summary, there is minimal decomposition of the gamma phase U-10Mo foil to alpha phase contamination following both plasma spraying and hot co-rolling. The average unit cell volume, i.e. lattice spacing, of the Zr layer can be mathematically extracted from the diffraction data; co-rolled Zr matches well with literature values of bulk Zr, while plasma sprayed Zr shows a slight increase in the lattice spacing, indicative of interstitial oxygen in the lattice. Neutron diffraction is a beneficial alternative to conventional methods of phase composition, i.e. x ray diffraction (XRD) and destructive metallography. XRD has minimal penetration depth in high atomic number materials, particularly uranium, and can only probe the first few microns of the fuel plate; neutrons pass completely through the foil, allowing for bulk analysis of the foil composition and no issues with addition of cladding layers, as in the final, aluminum-clad reactor fuel plates. Destructive metallography requires skilled technicians, cutting of the foil into small sections, hazardous etching conditions, long polishing and microscopy times, etc.; the neutron diffraction system has an automated sample loader and can fit larger foils, so there is minimal analysis preparation; the total spectrum acquisition time is ~ 1 hour per sample. The neutron diffraction results are limited by spectra refinement/calculation times and the availability of the neutron beam source. In the case of LANSCE at Los Alamos, the beam operates ~50% of the year. Following the lessons learned from these preliminary results, optimizations to

  12. Quantitative strain analysis for advanced CMOS technology by Nano Beam Diffraction

    KAUST Repository

    Wang, Qingxiao; Zhu, Jinmin; Du, Anyan; Liu, Jinping; Hua, YouNan

    2010-01-01

    Nano Beam Diffraction has been used to analyze the local strain distribution in MOS transistors. The influence of wafer process on the channel strain has been systematically analyzed in this paper. The source/drain implantation can cause a little strain loss but the silicidation step is the key process in which dramatic strain loss has been found. © 2010 IEEE.

  13. Quantitative strain analysis for advanced CMOS technology by Nano Beam Diffraction

    KAUST Repository

    Wang, Qingxiao

    2010-07-01

    Nano Beam Diffraction has been used to analyze the local strain distribution in MOS transistors. The influence of wafer process on the channel strain has been systematically analyzed in this paper. The source/drain implantation can cause a little strain loss but the silicidation step is the key process in which dramatic strain loss has been found. © 2010 IEEE.

  14. On a semiclassical analysis of high energy electron diffraction by imperfect crystals: the stacking fault

    International Nuclear Information System (INIS)

    Smith, A.E.; Chadderton, L.T.; Johnson, E.

    1978-01-01

    Electron diffraction amplitudes at the lower surface of a displaced sandwich crystal are obtained for the high energy limit in the real space formulation. Using semiclassical methods analytical approximations to a resulting overlap integral - central to the problem - are derived. (Auth.)

  15. Time-lapse misorientation maps for the analysis of electron backscatter diffraction data from evolving microstructures

    NARCIS (Netherlands)

    Wheeler, J.; Cross, A.; Drury, M.; Hough, R.M.; Mariani, E.; Piazolo, S.; Prior, D.J.

    2011-01-01

    A “time-lapse misorientation map” is defined here as a map which shows the orientation change at each point in an evolving crystalline microstructure between two different times. Electron backscatter diffraction data from in situ heating experiments can be used to produce such maps, which then

  16. Complex method for angular-spectral analysis of volume phase diffraction gratings recorded in photopolymers

    Czech Academy of Sciences Publication Activity Database

    Vojtíšek, Petr; Květoň, M.; Richter, I.

    2016-01-01

    Roč. 11, February (2016), č. článku 16009. ISSN 1990-2573 R&D Projects: GA MŠk(CZ) LO1206 Institutional support: RVO:61389021 Keywords : Photopolymers * diffraction gratings * angular-spectral maps * spectral selectivity * angular selectivity Subject RIV: BH - Optics, Masers, Lasers Impact factor: 0.975, year: 2016

  17. The structural analysis of zinc borate glass by laboratory EXAFS and X-ray diffraction measurements

    International Nuclear Information System (INIS)

    Kajinami, Akihiko; Harada, Yasushi; Inoue, Shinsuke; Deki, Shigehito; Umesaki, Norimasa

    1999-01-01

    The structure of zinc borate glass has been investigated by laboratory EXAFS and X-ray diffraction measurement as preliminary investigations for the detailed study in SPring-8. The zinc borate glass was prepared in the range from 40 to 65 mol% of zinc oxide content. The X-ray diffraction was measured by horizontal θ-θ goniometer with 60 kV and 300 mA output of Mo target. The EXAFS of zinc borate glass was measured by laboratory EXAFS system with 20 kV, 100 mA output of Mo target for the K absorption edge of zinc atom. From the X-ray diffraction and the EXAFS measurements, it is found that the zinc ion is surrounded by four oxygen atoms and formed a tetrahedral structure whose (Zn-O) distance is about 2 A and that the structure is unchanged with the zinc oxide content. The diffraction data show that the neighboring structure of boron atom transforms from BO 4 tetrahedra to BO 3 tetragonal planar structure with increasing of the zinc oxide content. (author)

  18. Analysis of dijet events in diffractive ep interactions with tagged leading proton at the H1 experiment

    Energy Technology Data Exchange (ETDEWEB)

    Polifka, Richard

    2011-08-15

    An inclusive dijet production in diffractive deep-inelastic scattering is measured. The diffractive selection is based on tagging of the leading proton in the Forward Proton Spectrometer. The statistics of events obtained during the HERA II running period (integrated luminosity of 156.7 pb{sup -1}) enables the measurement of jet final states with leading proton for the first time. The data cover the phase space of x{sub P}<0.1, vertical stroke t vertical stroke {<=}1.0 GeV{sup 2} and 4{<=} Q{sup 2} {<=}110 GeV{sup 2}. The dijet data are compared with the next to leading order predictions of the quantum chromodynamics (QCD). The phase space of diffractive dijets is in this analysis by factor of 3 in x{sub P} larger than in previous measurements. The QCD predictions based on the DGLAP parton evolution describe the measured data well even in a non-DGLAP enriched phase space where one on the jets goes into the region close to the direction of the outgoing proton. The measured single-differential cross sections are compared to several Monte Carlo models with different treatment of diffractive exchange implemented. (orig.)

  19. Analysis of dijet events in diffractive ep interactions with tagged leading proton at the H1 experiment

    International Nuclear Information System (INIS)

    Polifka, Richard

    2011-08-01

    An inclusive dijet production in diffractive deep-inelastic scattering is measured. The diffractive selection is based on tagging of the leading proton in the Forward Proton Spectrometer. The statistics of events obtained during the HERA II running period (integrated luminosity of 156.7 pb -1 ) enables the measurement of jet final states with leading proton for the first time. The data cover the phase space of x P 2 and 4≤ Q 2 ≤110 GeV 2 . The dijet data are compared with the next to leading order predictions of the quantum chromodynamics (QCD). The phase space of diffractive dijets is in this analysis by factor of 3 in x P larger than in previous measurements. The QCD predictions based on the DGLAP parton evolution describe the measured data well even in a non-DGLAP enriched phase space where one on the jets goes into the region close to the direction of the outgoing proton. The measured single-differential cross sections are compared to several Monte Carlo models with different treatment of diffractive exchange implemented. (orig.)

  20. Crystallization and preliminary X-ray diffraction analysis of the MIF4G domain of DAP5

    International Nuclear Information System (INIS)

    Frank, Filipp; Virgili, Geneviève; Sonenberg, Nahum; Nagar, Bhushan

    2009-01-01

    The MIF4G domain of DAP5 was crystallized in two distinct crystal forms. Diffraction patterns have been analyzed and preliminary analysis, including molecular replacement, is presented here. Death-associated protein 5 (DAP5) is a member of the eIF4G family of scaffolding proteins that mediate cap-independent translation initiation by recruiting the translational machinery to internal ribosomal entry sites (IRESs) on mRNA. The MIF4G domain of DAP5 directly interacts with the eukaryotic initiation factors eIF4A and eIF3 and enhances the translation of several viral and cellular IRESs. Here, the crystallization and preliminary X-ray diffraction analysis of the MIF4G domain of DAP5 is presented

  1. Three-dimensional grain mapping by x-ray diffraction contrast tomography and the use of Friedel pairs in diffraction data analysis

    DEFF Research Database (Denmark)

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

    2009-01-01

    X-ray diffraction contrast tomography (DCT) is a technique for mapping grain shape and orientation in plastically undeformed polycrystals. In this paper, we describe a modified DCT data acquisition strategy which permits the incorporation of an innovative Friedel pair method for analyzing...

  2. Crystallization and X-ray diffraction analysis of dihydropyrimidinase from Saccharomyces kluyveri

    International Nuclear Information System (INIS)

    Dobritzsch, Doreen; Andersen, Birgit; Piškur, Jure

    2005-01-01

    Dihydropyrimidinase from the yeast S. kluyveri was crystallized by vapour diffusion. The crystals belong to space group P2 1 (unit-cell parameters a = 91.0, b = 73.0, c = 161.4 Å, β = 91.4°) and diffracted to 2.6 Å resolution. Dihydropyrimidinase (EC 3.5.2.2) catalyzes the second step in the reductive pathway of pyrimidine degradation, the hydrolysis of 5,6-dihydrouracil and 5,6-dihydrothymine to the corresponding N-carbamylated β-amino acids. Crystals of the recombinant enzyme from the yeast Saccharomyces kluyveri diffracting to 2.6 Å at a synchrotron-radiation source have been obtained by the hanging-drop vapour-diffusion method. They belong to space group P2 1 (unit-cell parameters a = 91.0, b = 73.0, c = 161.4 Å, β = 91.4°), with one homotetramer per asymmetric unit

  3. 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.

  4. Crystallization and preliminary X-ray diffraction analysis of alanine racemase from Pseudomonas putida YZ-26

    International Nuclear Information System (INIS)

    Liu, Junlin; Feng, Lei; Shi, Yawei; Feng, Wei

    2012-01-01

    A recombinant alanine racemase from the Pseudomonas putida YZ-26, has been crystallized by the sitting-drop vapor-diffusion method and X-ray diffraction data were collected to 2.4 Å. A recombinant form of alanine racemase (Alr) from Pseudomonas putida YZ-26 has been crystallized by the sitting-drop vapour diffusion method. X-ray diffraction data were collected to 2.4 Å resolution. The crystals belong to the space group C222 1 , with unit-cell parameters a = 118.08, b = 141.86, c = 113.83 Å, and contain an Alr dimer in the asymmetric unit. The Matthews coefficient and the solvent content were calculated to be 2.8 Å 3 Da −1 and approximately 50%, respectively

  5. In-situ Indentation and Correlated Precession Electron Diffraction Analysis of a Polycrystalline Cu Thin Film

    Science.gov (United States)

    Guo, Qianying; Thompson, Gregory B.

    2018-04-01

    In-situ TEM nanoindentation of a polycrystalline Cu film was cross-correlated with precession electron diffraction (PED) to quantify the microstructural evolution. The use of PED is shown to clearly reveal features, such as grain size, that are easily masked by diffraction contrast created by the deformation. Using PED, the accompanying grain refinement and change in texture as well as the preservation of specific grain boundary structures, including a ∑3 boundary, under the indent impression were quantified. The nucleation of dislocations, evident in low-angle grain boundary formations, was also observed under the indent. PED quantification of texture gradients created by the indentation process linked well to bend contours observed in the bright-field images. Finally, PED enabled generating a local orientation spread map that gave an approximate estimation of the spatial distribution of strain created by the indentation impression.

  6. Crystallization and preliminary X-ray diffraction analysis of the fructofuranosidase from Xanthophyllomyces dendrorhous

    International Nuclear Information System (INIS)

    Polo, Aitana; Linde, Dolores; Estévez, Marta; Fernández-Lobato, María; Sanz-Aparicio, Julia

    2010-01-01

    The invertase from X. dendrorhous has been purified, deglycosylated and crystallized and diffraction data have been collected to 2.3 Å resolution. Xanthophyllomyces dendrorhous invertase is an extracellular enzyme that releases β-fructose from the nonreducing termini of various β-d-fructofuranoside substrates. Its ability to produce neokestose by transglycosylation makes this enzyme an interesting research target for applications in industrial biotechnology. The native enzyme, which is highly glycosylated, failed to crystallize. Therefore, it was submitted to EndoH deglycosylating treatment and crystals were grown by vapour-diffusion methods. The crystals belonged to space group P2 1 2 1 2, with unit-cell parameters a = 75.29, b = 204.93, c = 146.25 Å. Several diffraction data sets were collected using a synchrotron source. Self-rotation function and gel-filtration experiments suggested that the enzyme is a dimer with twofold symmetry

  7. Crystallization and diffraction analysis of β-N-acetylhexosaminidase from Aspergillus oryzae

    International Nuclear Information System (INIS)

    Vaněk, Ondřej; Brynda, Jiří; Hofbauerová, Kateřina; Kukačka, Zdeněk; Pachl, Petr; Bezouška, Karel; Řezáčová, Pavlína

    2011-01-01

    The fungal β-N-acetylhexosaminidase from A. oryzae was crystallized and diffraction data were collected from two crystal forms to 3.2 and 2.4 Å resolution, respectively. Fungal β-N-acetylhexosaminidases are enzymes that are used in the chemoenzymatic synthesis of biologically interesting oligosaccharides. The enzyme from Aspergillus oryzae was produced and purified from its natural source and crystallized using the hanging-drop vapour-diffusion method. Diffraction data from two crystal forms (primitive monoclinic and primitive tetragonal) were collected to resolutions of 3.2 and 2.4 Å, respectively. Electrophoretic and quantitative N-terminal protein-sequencing analyses confirmed that the crystals are formed by a complete biologically active enzyme consisting of a glycosylated catalytic unit and a noncovalently attached propeptide

  8. Analysis and Correction of Diffraction Effect on the B/A Measurement at High Frequencies

    Science.gov (United States)

    Zhang, Dong; Gong, Xiu-Fen; Liu, Xiao-Zhou; Kushibiki, Jun-ichi; Nishino, Hideo

    2004-01-01

    A numerical method is developed to analyse and to correct the diffraction effect in the measurement of acoustic nonlinearity parameter B/A at high frequencies. By using the KZK nonlinear equation and the superposition approach of Gaussian beams, an analytical model is derived to describe the second harmonic generation through multi-layer medium SiO2/liquid specimen/SiO2. Frequency dependence of the nonlinear characterization curve for water in 110-155 MHz is numerically and experimentally investigated. With the measured dip position and the new model, values of B/A for water are evaluated. The results show that the present method can effectively correct the diffraction effect in the measurement.

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

    International Nuclear Information System (INIS)

    Kiyota, Eduardo; Sousa, Sylvia Morais de; Santos, Marcelo Leite dos; Costa Lima, Aline da; Menossi, Marcelo; Yunes, José Andrés; Aparicio, Ricardo

    2007-01-01

    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 1 2 1 2 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

  10. X-ray diffraction analysis of particles ingested by filter-feeding animals

    International Nuclear Information System (INIS)

    Merritt, R.W.; Gersabeck, E.F.; Ross, D.H.; Mortland, M.M.

    1978-01-01

    The size and relative abundance of mineral particles ingested by two filter-feeding aquatic insects, Simulium vittatum Zett. (Diptera: Simuliidae) and Aedes triseriatus (Say) (Diptera: Culicidae) were determined by X-ray diffraction methods. Different minerals representing different particle size categories were supplied larval black flies and mosquitoes. Since minerals possess characteristic diffraction properties, their presence and relative abundance can be determined. Early instars of the black fly ingested and retained particles of three different size ranges: however, more coarse particles relative to fine particles were retained by smaller instars as compared with the larger instars. With mosquito larvae, there was a proportional increase in coarser material ingested with increasing age and size of larvae. Other applications of this method are discussed. (Auth.)

  11. Expression, purification, crystallization and preliminary X-ray diffraction analysis of nurse shark β2-microglobulin

    OpenAIRE

    Lu, Shuangshuang; Yao, Shugang; Chen, Rong; Zhang, Nianzhi; Chen, Jianmin; Gao, Feng; Xia, Chun

    2012-01-01

    A crystal of nurse shark β2-microglobulin diffracted to 2.3 Å resolution and belonged to space group P3221, with unit-cell parameters a = b = 88.230, c = 67.146 Å and two molecules per asymmetric unit. The Matthews coefficient V M was calculated to be about 3.28 Å3 Da−1, corresponding to 62.5% solvent content.

  12. Time-lapse misorientation maps for the analysis of electron backscatter diffraction data from evolving microstructures

    International Nuclear Information System (INIS)

    Wheeler, J.; Cross, A.; Drury, M.; Hough, R.M.; Mariani, E.; Piazolo, S.; Prior, D.J.

    2011-01-01

    A 'time-lapse misorientation map' is defined here as a map which shows the orientation change at each point in an evolving crystalline microstructure between two different times. Electron backscatter diffraction data from in situ heating experiments can be used to produce such maps, which then highlight areas of microstructural change and also yield statistics indicative of how far different types of boundary (with different misorientations) have moved.

  13. Quantitative analysis of calcined fertilizers by X-ray diffraction patterns

    International Nuclear Information System (INIS)

    Cekinski, E.

    1987-01-01

    An X-ray diffraction pattern method for quantitative analyses of phosphate fertilizers obtained by calcination of a misture of Anitapolis phosphate concentrate and sodium carbonate is described. The method consists in plotting a calibration curve, using spinel (MgAl 2 O 4 ) as internal standard, of the phases that were formed by calcination, sintetized in laboratory. The tests conducted in order to avail the method accuracy showed good correlation between the obtained data and the real values. (author) [pt

  14. Crystallization and diffraction analysis of the serpin IRS-2 from the hard tick Ixodes ricinus

    International Nuclear Information System (INIS)

    Kovářová, Zuzana; Chmelař, Jindřich; Šanda, Miloslav; Brynda, Jiří; Mareš, Michael; Řezáčová, Pavlína

    2010-01-01

    Cleavage of the serpin IRS-2 from the hard tick I. ricinus by contaminating proteolytic activity mimicked the specific processing of the serpin by its target protease and resulted in a more stable form of the serpin which produced crystals that diffracted to 1.8 Å resolution. IRS-2 from the hard tick Ixodes ricinus belongs to the serpin family of protease inhibitors. It is produced in the salivary glands of the tick and its anti-inflammatory activity suggests that it plays a role in parasite–host interaction. Recombinant IRS-2 prepared by heterologous expression in a bacterial system was crystallized using the hanging-drop vapour-diffusion method. The crystals belonged to the primitive tetragonal space group P4 3 and diffracted to 1.8 Å resolution. Mass-spectrometric and electrophoretic analyses revealed that IRS-2 was cleaved by contaminating proteases during crystallization. This processing of IRS-2 mimicked the specific cleavage of the serpin by its target protease and resulted in a more stable form (the so-called relaxed conformation), which produced well diffracting crystals. Activity profiling with specific substrates and inhibitors demonstrated traces of serine and cysteine proteases in the protein stock solution

  15. Analysis of synchrotron X-ray diffraction patterns from fluorotic enamel samples

    Energy Technology Data Exchange (ETDEWEB)

    Almeida, Ana P.G.; Braz, Delson, E-mail: anapaulagalmeida@gmail.co [Coordenacao dos Programas de Pos-graduacao de Engenharia (COPPE/UFRJ), Rio de Janeiro, RJ (Brazil). Lab. de Instrumentacao Nuclear; Colaco, Marcos V.; Barroso, Regina C., E-mail: cely@uerj.b [Universidade do Estado do Rio de Janeiro (UERJ), RJ (Brazil). Inst. de Fisica; Porto, Isabel M., E-mail: belporto@ig.com.b [Universidade Estadual de Campinas (UNICAMP), Piracicaba, SP (Brazil). Faculdade de Odontologia; Gerlach, Raquel F., E-mail: rfgerlach@forp.usp.b [Universidade de Sao Paulo (USP), Ribeirao Preto, SP (Brazil). Faculdade de Odontologia; Droppa Junior, Roosevelt, E-mail: rdroppa@lnls.b [Associacao Brasileira de Tecnologia de Luz Sincrotron (ABTLuS), Campinas, SP (Brazil)

    2009-07-01

    With the introduction of fluoride as the main anticaries agent used in preventive dentistry, and perhaps an increase in fluoride in our food chain, dental fluorosis has become an increasing world-wide problem. Visible signs of fluorosis begin to become obvious on the enamel surface as opacities, implying some porosity in the tissue. The mechanisms that conduct the formation of fluorotic enamel are unknown, but should involve modifications in the basics physical-chemistry reactions of demineralisation and remineralisation of the enamel of the teeth, which is the same reaction of formation of the enamel's hydroxyapatite (HAp) in the maturation phase. The increase of the amount of fluoride inside of the apatite will result in gradual increase of the lattice parameters. The hexagonal symmetry seems to work well with the powder diffraction data, and the crystal structure of HAp is usually described in space group P63/m. The aim of this work is to characterize the healthy and fluorotic enamel in human tooth using technique Synchrotron X-ray diffraction in order to determine the crystal structure and crystallinity of on fluoroapatite (FAp) crystal present in fluoritic enamel. All the scattering profile measurements was carried out at the X-ray diffraction beamline (XRD1) at the National Synchrotron Light Laboratory - LNLS, Campinas, Brazil. (author)

  16. Ab initio structure determination and quantitative disorder analysis on nanoparticles by electron diffraction tomography.

    Science.gov (United States)

    Krysiak, Yaşar; Barton, Bastian; Marler, Bernd; Neder, Reinhard B; Kolb, Ute

    2018-03-01

    Nanoscaled porous materials such as zeolites have attracted substantial attention in industry due to their catalytic activity, and their performance in sorption and separation processes. In order to understand the properties of such materials, current research focuses increasingly on the determination of structural features beyond the averaged crystal structure. Small particle sizes, various types of disorder and intergrown structures render the description of structures at atomic level by standard crystallographic methods difficult. This paper reports the characterization of a strongly disordered zeolite structure, using a combination of electron exit-wave reconstruction, automated diffraction tomography (ADT), crystal disorder modelling and electron diffraction simulations. Zeolite beta was chosen for a proof-of-principle study of the techniques, because it consists of two different intergrown polymorphs that are built from identical layer types but with different stacking sequences. Imaging of the projected inner Coulomb potential of zeolite beta crystals shows the intergrowth of the polymorphs BEA and BEB. The structures of BEA as well as BEB could be extracted from one single ADT data set using direct methods. A ratio for BEA/BEB = 48:52 was determined by comparison of the reconstructed reciprocal space based on ADT data with simulated electron diffraction data for virtual nanocrystals, built with different ratios of BEA/BEB. In this way, it is demonstrated that this smart interplay of the above-mentioned techniques allows the elaboration of the real structures of functional materials in detail - even if they possess a severely disordered structure.

  17. Neutron diffraction analysis of the structure of rod photoreceptor membranes in intact retinas

    Energy Technology Data Exchange (ETDEWEB)

    Yaeger, M; Schoenborn, B; Engelman, D; Moore, P; Stryer, L

    1980-01-01

    Neutron diffraction data have been collected from samples containing ten dark-adapted Rana catesbiana bullfrog retinas in 100, 80, 60, 40, and 30% D/sub 2/O Ringer's solution using a step-scanning Soller slit diffractometer. Diffraction was also recorded from retinas equilibrated in D/sub 2/O solutions with varying osmolarity. Rocking curve experiments demonstrated that the rods are disoriented in a cylindrically symmetrical fashion. Structure factor amplitudes were obtained using semi-automated curve-fitting procedures, and phases were obtained by interpreting the D/sub 2/O-H/sub 2/O and osmotic Patterson maps. In D/sub 2/O Ringer's solution the first four structure factors are -353 +- 25, 246 +- 19, 434 +- 13 and 383 +- 19. Neutron scattering density profiles were calculated to 75 A resolution using these structure factors. These neutron diffraction data are consistent with the view that the lipid bilayer is a major structural motif of the rod outer segment disc membrane. Neutron Fourier syntheses in different mixtures of D/sub 2/O and H/sub 2/O indicate that the intradisc and extradisc spaces are predominantly aqueous, consistent with the increase in the intradisc and extradisc volumes as the Ringer's solution is made more hypotomic. In isotonic Ringer's solution, the thicknesses of the intradisc and extradisc spaces are about 36 A and 160 A, respectively, and the center-to-center separation between the 50 A thick lipid bilayer is 88 A.

  18. Analysis of synchrotron X-ray diffraction patterns from fluorotic enamel samples

    International Nuclear Information System (INIS)

    Almeida, Ana P.G.; Braz, Delson

    2009-01-01

    With the introduction of fluoride as the main anticaries agent used in preventive dentistry, and perhaps an increase in fluoride in our food chain, dental fluorosis has become an increasing world-wide problem. Visible signs of fluorosis begin to become obvious on the enamel surface as opacities, implying some porosity in the tissue. The mechanisms that conduct the formation of fluorotic enamel are unknown, but should involve modifications in the basics physical-chemistry reactions of demineralisation and remineralisation of the enamel of the teeth, which is the same reaction of formation of the enamel's hydroxyapatite (HAp) in the maturation phase. The increase of the amount of fluoride inside of the apatite will result in gradual increase of the lattice parameters. The hexagonal symmetry seems to work well with the powder diffraction data, and the crystal structure of HAp is usually described in space group P63/m. The aim of this work is to characterize the healthy and fluorotic enamel in human tooth using technique Synchrotron X-ray diffraction in order to determine the crystal structure and crystallinity of on fluoroapatite (FAp) crystal present in fluoritic enamel. All the scattering profile measurements was carried out at the X-ray diffraction beamline (XRD1) at the National Synchrotron Light Laboratory - LNLS, Campinas, Brazil. (author)

  19. On the use of a composite moderator at the IBR-2 reactor: Advantages for the neutron-diffraction texture analysis of rocks

    Czech Academy of Sciences Publication Activity Database

    Bulavin, M. V.; Vasin, R.N.; Kulikov, S.A.; Lokajíček, Tomáš; Levin, D.M.

    2016-01-01

    Roč. 10, č. 4 (2016), s. 677-686 ISSN 1027-4510 Institutional support: RVO:67985831 Keywords : cold moderator * neutron-diffraction texture analysis * phase analysis * Rietveld method Subject RIV: DB - Geology ; Mineralogy

  20. Thermal and X-ray diffraction analysis studies during the decomposition of ammonium uranyl nitrate.

    Science.gov (United States)

    Kim, B H; Lee, Y B; Prelas, M A; Ghosh, T K

    Two types of ammonium uranyl nitrate (NH 4 ) 2 UO 2 (NO 3 ) 4 ·2H 2 O and NH 4 UO 2 (NO 3 ) 3 , were thermally decomposed and reduced in a TG-DTA unit in nitrogen, air, and hydrogen atmospheres. Various intermediate phases produced by the thermal decomposition and reduction process were investigated by an X-ray diffraction analysis and a TG/DTA analysis. Both (NH 4 ) 2 UO 2 (NO 3 ) 4 ·2H 2 O and NH 4 UO 2 (NO 3 ) 3 decomposed to amorphous UO 3 regardless of the atmosphere used. The amorphous UO 3 from (NH 4 ) 2 UO 2 (NO 3 ) 4 ·2H 2 O was crystallized to γ-UO 3 regardless of the atmosphere used without a change in weight. The amorphous UO 3 obtained from decomposition of NH 4 UO 2 (NO 3 ) 3 was crystallized to α-UO 3 under a nitrogen and air atmosphere, and to β-UO 3 under a hydrogen atmosphere without a change in weight. Under each atmosphere, the reaction paths of (NH 4 ) 2 UO 2 (NO 3 ) 4 ·2H 2 O and NH 4 UO 2 (NO 3 ) 3 were as follows: under a nitrogen atmosphere: (NH 4 ) 2 UO 2 (NO 3 ) 4 ·2H 2 O → (NH 4 ) 2 UO 2 (NO 3 ) 4 ·H 2 O → (NH 4 ) 2 UO 2 (NO 3 ) 4  → NH 4 UO 2 (NO 3 ) 3  → A-UO 3  → γ-UO 3  → U 3 O 8 , NH 4 UO 2 (NO 3 ) 3  → A-UO 3  → α-UO 3  → U 3 O 8 ; under an air atmosphere: (NH 4 ) 2 UO 2 (NO 3 ) 4 ·2H 2 O → (NH 4 ) 2 UO 2 (NO 3 ) 4 ·H 2 O → (NH 4 ) 2 UO 2 (NO 3 ) 4  → NH 4 UO 2 (NO 3 ) 3  → A-UO 3  → γ-UO 3  → U 3 O 8 , NH 4 UO 2 (NO 3 ) 3  → A-UO 3  → α-UO 3  → U 3 O 8 ; and under a hydrogen atmosphere: (NH 4 ) 2 UO 2 (NO 3 ) 4 ·2H 2 O → (NH 4 ) 2 UO 2 (NO 3 ) 4 ·H 2 O → (NH 4 ) 2 UO 2 (NO 3 ) 4  → NH 4 UO 2 (NO 3 ) 3  → A-UO 3  → γ-UO 3  → α-U 3 O 8  → UO 2 , NH 4 UO 2 (NO 3 ) 3  → A-UO 3  → β-UO 3  → α-U 3 O 8  → UO 2 .

  1. Escherichia coli tRNAArg acceptor-stem isoacceptors: comparative crystallization and preliminary X-ray diffraction analysis

    International Nuclear Information System (INIS)

    Eichert, André; Schreiber, Angela; Fürste, Jens P.; Perbandt, Markus; Betzel, Christian; Erdmann, Volker A.; Förster, Charlotte

    2009-01-01

    Various E. coli tRNA Arg acceptor-stem microhelix isoacceptors have been crystallized and investigated by high-resolution X-ray diffraction analysis. The aminoacylation of tRNA is a crucial step in cellular protein biosynthesis. Recognition of the cognate tRNA by the correct aminoacyl-tRNA synthetase is ensured by tRNA identity elements. In tRNA Arg , the identity elements consist of the anticodon, parts of the D-loop and the discriminator base. The minor groove of the aminoacyl stem interacts with the arginyl-tRNA synthetase. As a consequence of the redundancy of the genetic code, six tRNA Arg isoacceptors exist. In the present work, three different Escherichia coli tRNA Arg acceptor-stem helices were crystallized. Two of them, the tRNA Arg microhelices RR-1660 and RR-1662, were examined by X-ray diffraction analysis and diffracted to 1.7 and 1.8 Å resolution, respectively. The tRNA Arg RR-1660 helix crystallized in space group P1, with unit-cell parameters a = 26.28, b = 28.92, c = 29.00 Å, α = 105.74, β = 99.01, γ = 97.44°, whereas the tRNA Arg RR-1662 helix crystallized in space group C2, with unit-cell parameters a = 33.18, b = 46.16, c = 26.04 Å, β = 101.50°

  2. Crystallization and preliminary X-ray diffraction analysis of l,l-diaminopimelate aminotransferase (DapL) from Chlamydomonas reinhardtii

    International Nuclear Information System (INIS)

    Hudson, André O.; Girón, Irma; Dobson, Renwick C. J.

    2010-01-01

    A variant of the diaminopimelate/lysine pathway has recently been defined following the discovery of the enzyme l,l-diaminopimelate aminotransferase (DapL). The cloning of the cDNA, recombinant expression, purification and preliminary diffraction analysis of DapL from the alga C. reinhardtii are presented. In the anabolic synthesis of diaminopimelate and lysine in plants and in some bacteria, the enzyme l,l-diaminopimelate aminotransferase (DapL; EC 2.6.1.83) catalyzes the conversion of tetrahydrodipicolinic acid (THDPA) to l,l-diaminopimelate, bypassing the DapD, DapC and DapE enzymatic steps in the bacterial acyl pathways. Here, the cloning, expression, purification, crystallization and preliminary X-ray diffraction analysis of DapL from the alga Chlamydomonas reinhardtii are presented. Protein crystals were grown in conditions containing 25%(w/v) PEG 3350 and 200 mM lithium sulfate and initially diffracted to ∼1.35 Å resolution. They belonged to space group P2 1 2 1 2 1 , with unit-cell parameters a = 58.9, b = 91.8, c = 162.9 Å. The data were processed to 1.55 Å resolution with an R merge of 0.081, an R p.i.m. of 0.044, an R r.i.m of 0.093 and a V M of 2.28 Å 3 Da −1

  3. A structural investigation into the compaction behavior of pharmaceutical composites using powder X-ray diffraction and total scattering analysis.

    Science.gov (United States)

    Moore, Michael D; Steinbach, Alison M; Buckner, Ira S; Wildfong, Peter L D

    2009-11-01

    To use advanced powder X-ray diffraction (PXRD) to characterize the structure of anhydrous theophylline following compaction, alone, and as part of a binary mixture with either alpha-lactose monohydrate or microcrystalline cellulose. Compacts formed from (1) pure theophylline and (2) each type of binary mixture were analyzed intact using PXRD. A novel mathematical technique was used to accurately separate multi-component diffraction patterns. The pair distribution function (PDF) of isolated theophylline diffraction data was employed to assess structural differences induced by consolidation and evaluated by principal components analysis (PCA). Changes induced in PXRD patterns by increasing compaction pressure were amplified by the PDF. Simulated data suggest PDF dampening is attributable to molecular deviations from average crystalline position. Samples compacted at different pressures were identified and differentiated using PCA. Samples compacted at common pressures exhibited similar inter-atomic correlations, where excipient concentration factored in the analyses involving lactose. Practical real-space structural analysis of PXRD data by PDF was accomplished for intact, compacted crystalline drug with and without excipient. PCA was used to compare multiple PDFs and successfully differentiated pattern changes consistent with compaction-induced disordering of theophylline as a single component and in the presence of another material.

  4. Determination of dislocation density by electron backscatter diffraction and X-ray line profile analysis in ferrous lath martensite

    International Nuclear Information System (INIS)

    Berecz, Tibor; Jenei, Péter; Csóré, András; Lábár, János; Gubicza, Jenő

    2016-01-01

    The microstructure and the dislocation density in as-quenched ferrous lath martensite were studied by different methods. The blocks, packets and variants formed due to martensitic transformation were identified and their sizes were determined by electron backscatter diffraction (EBSD). Concomitant transmission electron microscopy (TEM) investigation revealed that the laths contain subgrains with the size between 50 and 100 nm. A novel evaluation procedure of EBSD images was elaborated for the determination of the density and the space distribution of geometrically necessary dislocations from the misorientation distribution. The total dislocation density obtained by X-ray diffraction line profile analysis was in good agreement with the value determined by EBSD, indicating that the majority of dislocations formed due to martensitic transformation during quenching are geometrically necessary dislocations.

  5. The IPNS rietveld analysis software package for TOF [time-of-flight] powder diffraction data: Recent developments

    International Nuclear Information System (INIS)

    Rotella, F.J.; Richardson, J.W. Jr.

    1987-01-01

    A system of FORTRAN programs for the analysis of time-of-flight (TOF) neutron powder diffraction data via the Rietveld method at IPNS has been modified recently, making it possible to analyze data that exhibit diffraction maxima broadened due to anisotropic strain and that can be modeled by individual atomic anharmonic thermal vibrations. The observation of noncrystalline scattering in data from some powder samples has led to the development of software to fit such scattering by a function related to a radial distribution function through Fourier-filtering techniques. The ''user friendliness'' of the IPNS Rietveld package has been enhanced by the development of ''RIETVELD,'' a menu-based VAX/VMS command language routine for interactive file manipulation and program execution

  6. Subreflector extension for improved efficiencies in Cassegrain antennas - GTD/PO analysis. [Geometrical Theory of Diffraction/Physical Optics

    Science.gov (United States)

    Rahmat-Samii, Yahya

    1986-01-01

    Both offset and symmetric Cassegrain reflector antennas are used in satellite and ground communication systems. It is known that the subreflector diffraction can degrade the performance of these reflectors. A geometrical theory of diffraction/physical optics analysis technique is used to investigate the effects of the extended subreflector, beyond its optical rim, on the reflector efficiency and far-field patterns. Representative numerical results are shown for an offset Cassegrain reflector antenna with different feed illumination tapers and subreflector extensions. It is observed that for subreflector extensions as small as one wavelength, noticeable improvements in the overall efficiencies can be expected. Useful design data are generated for the efficiency curves and far-field patterns.

  7. Detailed Analysis of Amplitude and Slope Diffraction Coefficients for knife-edge structure in S-UTD-CH Model

    Directory of Open Access Journals (Sweden)

    Eray Arik

    2017-03-01

    Full Text Available In urban, rural and indoor applications, diffraction mechanism is very important to predict the field strength and calculate the coverage accurately. The diffraction mechanism takes place on NLOS (non-line-of-sight cases like rooftop, vertex, corner, edge and sharp surfaces. S-UTD-CH model computes three type of electromagnetic wave incidence such as direct, reflected and diffracted waves, respectively. As obstacles in diffraction geometry are in the same or closer height, contribution of the diffraction mechanism is dominant. To predict the diffracted fields accurately, amplitude and slope diffraction coefficients and the derivative of these coefficients have to be taken correctly. In this paper, all the derivations about diffraction coefficients are made for knife edge type structures and extensive simulations are performed in order to analyze the amplitude and diffraction coefficients. In plane angle diffraction, contributions of amplitude and slope diffraction coefficient are maxima.

  8. Fibre Diffraction Analysis of Skin Offers a Very Early and Extremely Accurate Diagnostic Test for Prostate Cancer

    Energy Technology Data Exchange (ETDEWEB)

    James, Veronica J. [Research School of Chemistry, Australian National University, Canberra, ACT 0200, Australia; O’Malley Ford, Judith M. [Kedron 7 Day Medical Centre, Kedron, Brisbane, QLD 4005, Australia

    2014-01-01

    Double blind analysis of a batch of thirty skin tissue samples from potential prostate cancer sufferers correctly identified all “control” patients, patients with high and low grade prostate cancers, the presence of benign prostate hyperplasia (BPH), perineural invasions, and the one lymphatic invasion. Identification was by analysis of fibre diffraction patterns interpreted using a schema developed from observations in nine previous studies. The method, schema, and specific experiment results are reported in this paper, with some implications then drawn.

  9. Diffraction dissociation

    International Nuclear Information System (INIS)

    Abarbanel, H.

    1972-01-01

    An attempt is made to analyse the present theoretical situation in the field of diffraction scattering. Two not yet fully answered questions related with a typical diffraction process AB→CD, namely: what is the structure of the transition matrix elements, and what is the structure of the exchange mechanism responsible for the scattering, are formulated and various proposals for answers are reviewed. Interesting general statement that the products (-1)sup(J)P, where J and P are respectively spin and parity, is conserved at each vertex has been discussed. The exchange mechanism in diffractive scattering has been considered using the language of the complex J-plane as the most appropriate. The known facts about the exchange mechanism are recalled and several routs to way out are proposed. The idea to consider the moving pole and associated branch points as like a particle and the associated two and many particle unitarity cuts is described in more details. (S.B.)

  10. On the use of logarithmic scales for analysis of diffraction data.

    Science.gov (United States)

    Urzhumtsev, Alexandre; Afonine, Pavel V; Adams, Paul D

    2009-12-01

    Predictions of the possible model parameterization and of the values of model characteristics such as R factors are important for macromolecular refinement and validation protocols. One of the key parameters defining these and other values is the resolution of the experimentally measured diffraction data. The higher the resolution, the larger the number of diffraction data N(ref), the larger its ratio to the number N(at) of non-H atoms, the more parameters per atom can be used for modelling and the more precise and detailed a model can be obtained. The ratio N(ref)/N(at) was calculated for models deposited in the Protein Data Bank as a function of the resolution at which the structures were reported. The most frequent values for this distribution depend essentially linearly on resolution when the latter is expressed on a uniform logarithmic scale. This defines simple analytic formulae for the typical Matthews coefficient and for the typically allowed number of parameters per atom for crystals diffracting to a given resolution. This simple dependence makes it possible in many cases to estimate the expected resolution of the experimental data for a crystal with a given Matthews coefficient. When expressed using the same logarithmic scale, the most frequent values for R and R(free) factors and for their difference are also essentially linear across a large resolution range. The minimal R-factor values are practically constant at resolutions better than 3 A, below which they begin to grow sharply. This simple dependence on the resolution allows the prediction of expected R-factor values for unknown structures and may be used to guide model refinement and validation.

  11. 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)

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

    Science.gov (United States)

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

    2010-01-01

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

  13. Diffractive axicons in oblique illumination: analysis and experiments and comparison with elliptical axicons.

    Science.gov (United States)

    Thaning, Anna; Jaroszewicz, Zbigniew; Friberg, Ari T

    2003-01-01

    Axicons in oblique illumination produce broadened focal lines, a problem, e.g., in scanning applications. A compact mathematical description of the focal segment is presented, for the first time, to our knowledge, and the results are compared with elliptical axicons in normal illumination. In both cases, analytical expressions in the form of asteroid curves are obtained from asymptotic wave theory and caustic surfaces. The results are confirmed by direct diffraction simulations and by experiments. In addition we show that at a fixed angle an elliptical axicon can be used to compensate for the adverse effects of oblique illumination.

  14. A semiclassical analysis of high energy electron diffraction by stacking faults: arrival at the classical limit

    International Nuclear Information System (INIS)

    Smith, A.E.; Chadderton, L.T.

    1978-01-01

    In a recent note the authors summarised results for an extension of Berry's theory to cover the one-dimensional problem of systematic reflections (planes) for a thin crystal sandwich consisting of two identical slabs of lattice parameter 'a' with a relative horizontal displacement 'f'. The diffraction amplitudes at the lower surface of the crystal were shown to depend on a double summation over the various transverse energy states in the upper and lower slab respectively, and on the transitions between them. In this report the authors demonstrate the arrival at the classical limit for the problem and, in particular, indicate briefly the nature of the topologically different classical paths. (Auth.)

  15. Texture of poled tetragonal PZT detected by synchrotron X-ray diffraction and micromechanics analysis

    International Nuclear Information System (INIS)

    Hall, D.A.; Steuwer, A.; Cherdhirunkorn, B.; Withers, P.J.; Mori, T.

    2005-01-01

    The texture and lattice elastic strain due to electrical poling of tetragonal PZT (lead zirconate titanate) ceramics have been measured using high energy synchrotron X-ray diffraction. It is shown that XRD peak intensity ratios associated with crystal planes of the form {002}, {112} and {202} exhibit a linear dependence on cos-bar 2 Ψ, where Ψ represents the orientation angle between the plane normal and the macroscopic poling axis. The observed dependence of texture and lattice strain on the grain orientation can be understood on the basis that the macroscopic strain due to poling is the average of the poling strains of all the individual grains

  16. Crystallization and preliminary X-ray diffraction analysis of PAT, an acetyltransferase from Sulfolobus solfataricus

    International Nuclear Information System (INIS)

    Cho, Ching-Chang; Luo, Ching-Wei; Hsu, Chun-Hua

    2008-01-01

    PAT, an acetyltransferase from the archaeon S. solfataricus that specifically acetylates the chromatin protein Alba, was expressed, purified and crystallized. PAT is an acetyltransferase from the archaeon Sulfolobus solfataricus that specifically acetylates the chromatin protein Alba. The enzyme was expressed, purified and subsequently crystallized using the sitting-drop vapour-diffusion technique. Native diffraction data were collected to 1.70 Å resolution on the BL13C1 beamline of NSRRC from a flash-frozen crystal at 100 K. The crystals belonged to space group P2 1 2 1 2 1 , with unit-cell parameters a = 44.30, b = 46.59, c = 68.39 Å

  17. Diffraction attraction

    International Nuclear Information System (INIS)

    Anon.

    1986-01-01

    Elastic scattering – when colliding particles 'bounce' off each other like billiard balls – has always had a special interest for high energy physicists. While its simplicity makes for deep analogies with classical ideas like diffraction, its jbtle details also test our understanding of the intricate inner mechanisms which drive particle interactions. With a new stock of elastic scattering data now available thanks to experiments at the CERN proton-antiproton Collider, and with studies at higher energies imminent or planned, some seventy physicists gathered in the magnificent chateau at Blois, France, for a 'Workshop on Elastic and Diffractive Scattering at the Collider and Beyond'

  18. Diffractive scattering

    CERN Document Server

    De Wolf, E.A.

    2002-01-01

    We discuss basic concepts and properties of diffractive phenomena in soft hadron collisions and in deep-inelastic scattering at low Bjorken-x. The paper is not a review of the rapidly developing field but presents an attempt to show in simple terms the close inter-relationship between the dynamics of high-energy hadronic and deep-inelastic diffraction. Using the saturation model of Golec-Biernat and Wusthoff as an example, a simple explanation of geometrical scaling is presented. The relation between the QCD anomalous multiplicity dimension and the Pomeron intercept is discussed.

  19. Diffractive Scattering

    International Nuclear Information System (INIS)

    Wolf, E.A. de

    2002-01-01

    We discuss basic concepts and properties of diffractive phenomena in soft hadron collisions and in deep-inelastic scattering at low Bjorken - x. The paper is not a review of the rapidly developing field but presents an attempt to show in simple terms the close inter-relationship between the dynamics of high-energy hadronic and deep-inelastic diffraction. Using the saturation model of Golec-Biernat and Wuesthoff as an example, a simple explanation of geometrical scaling is presented. The relation between the QCD anomalous multiplicity dimension and the Pomeron intercept is discussed. (author)

  20. Diffraction attraction

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1986-03-15

    Elastic scattering – when colliding particles 'bounce' off each other like billiard balls – has always had a special interest for high energy physicists. While its simplicity makes for deep analogies with classical ideas like diffraction, its jbtle details also test our understanding of the intricate inner mechanisms which drive particle interactions. With a new stock of elastic scattering data now available thanks to experiments at the CERN proton-antiproton Collider, and with studies at higher energies imminent or planned, some seventy physicists gathered in the magnificent chateau at Blois, France, for a 'Workshop on Elastic and Diffractive Scattering at the Collider and Beyond'.

  1. Purification, crystallization and preliminary X-ray diffraction analysis of the HMG domain of Sox17 in complex with DNA

    International Nuclear Information System (INIS)

    Ng, Calista Keow Leng; Palasingam, Paaventhan; Venkatachalam, Rajakannan; Baburajendran, Nithya; Cheng, Jason; Jauch, Ralf; Kolatkar, Prasanna R.

    2008-01-01

    Crystals of the Sox17 HMG domain bound to LAMA1 enhancer DNA-element crystals that diffracted to 2.75 Å resolution were obtained. Sox17 is a member of the SRY-related high-mobility group (HMG) of transcription factors that have been shown to direct endodermal differentiation in early mammalian development. The LAMA1 gene encoding the α-chain of laminin-1 has been reported to be directly bound and regulated by Sox17. This paper describes the details of initial crystallization attempts with the HMG domain of mouse Sox17 (mSox17-HMG) with a 16-mer DNA element derived from the LAMA1 enhancer and optimization strategies to obtain a better diffracting crystal. The best diffracting crystal was obtained in a condition containing 0.1 M Tris–HCl pH 7.4, 0.2 M MgCl 2 , 30% PEG 3350 using the hanging-drop vapour-diffusion method. A highly redundant in-house data set was collected to 2.75 Å resolution with 99% completeness. The presence of the mSox17-HMG–DNA complex within the crystals was confirmed and Matthews analysis indicated the presence of one complex per asymmetric unit

  2. Crystallization and preliminary X-ray diffraction analysis of the lytic transglycosylase MltE from Escherichia coli

    International Nuclear Information System (INIS)

    Artola-Recolons, Cecilia; Llarrull, Leticia I.; Lastochkin, Elena; Mobashery, Shahriar; Hermoso, Juan A.

    2010-01-01

    Crystals of the lytic transglycosylase MltE from E. coli were grown using the microbatch method and diffracted to a resolution of 2.1 Å. MltE from Escherichia coli (193 amino acids, 21 380 Da) is a lytic transglycosylase that initiates the first step of cell-wall recycling. This enzyme is responsible for the cleavage of the cell-wall peptidoglycan at the β-1,4-glycosidic bond between the N-acetylglucosamine and N-acetylmuramic acid units. At the end this reaction generates a disaccharide that is internalized and initiates the recycling process. To obtain insights into the biological functions of MltE, crystallization trials were performed and crystals of MltE protein that were suitable for X-ray diffraction analysis were obtained. The MltE protein of E. coli was crystallized using the hanging-drop vapour-diffusion method at 291 K. Crystals grew from a mixture consisting of 28% polyethylene glycol 4000, 0.1 M Tris pH 8.4 and 0.2 M magnesium chloride. Further optimization was performed using the microbatch technique. Single crystals were obtained that belonged to the orthorhombic space group C222 1 , with unit-cell parameters a = 123.32, b = 183.93, c = 35.29 Å, and diffracted to a resolution of 2.1 Å

  3. Crystallization and preliminary X-ray diffraction analysis of a specific VHH domain against mouse prion protein

    International Nuclear Information System (INIS)

    Abskharon, Romany N. N.; Soror, Sameh H.; Pardon, Els; El Hassan, Hassan; Legname, Giuseppe; Steyaert, Jan; Wohlkonig, Alexandre

    2010-01-01

    The crystallization of a specific nanobody against mouse PrP C and preliminary diffraction analysis of a crystal that diffracted to 1.23 Å resolution are presented. Prion disorders are infectious diseases that are characterized by the conversion of the cellular prion protein PrP C into the pathogenic isoform PrP Sc . Specific antibodies that interact with the cellular prion protein have been shown to inhibit this transition. Recombinant VHHs (variable domain of dromedary heavy-chain antibodies) or nanobodies are single-domain antibodies, making them the smallest antigen-binding fragments. A specific nanobody (Nb-PrP-01) was raised against mouse PrP C . A crystallization condition for this recombinant nanobody was identified using high-throughput screening. The crystals were optimized using streak-seeding and the hanging-drop method. The crystals belonged to the orthorhombic space group P2 1 2 1 2 1 , with unit-cell parameters a = 30.04, b = 37.15, c = 83.00 Å, and diffracted to 1.23 Å resolution using synchrotron radiation. The crystal structure of this specific nanobody against PrP C together with the known PrP C structure may help in understanding the PrP C /PrP Sc transition mechanism

  4. Cloning, expression, purification, crystallization and preliminary X-ray diffraction analysis of the regulator AcrR from Escherichia coli

    International Nuclear Information System (INIS)

    Li, Ming; Qiu, Xi; Su, Chih-Chia; Long, Feng; Gu, Ruoyu; McDermott, Gerry; Yu, Edward W.

    2006-01-01

    The transcriptional regulator AcrR from Escherichia coli has been cloned, overexpressed, purified and crystallized and X-ray diffraction data have been collected to a resolution of 2.5 Å. This paper describes the cloning, expression, purification and preliminary X-ray data analysis of the AcrR regulatory protein. The Escherichia coli AcrR is a member of the TetR family of transcriptional regulators. It regulates the expression of the AcrAB multidrug transporter. Recombinant AcrR with a 6×His tag at the C-terminus was expressed in E. coli and purified by metal-affinity chromatography. The protein was crystallized using hanging-drop vapor diffusion. X-ray diffraction data were collected from cryocooled crystals at a synchrotron light source. The best crystal diffracted to 2.5 Å. The space group was determined to be P3 2 , with unit-cell parameters a = b = 46.61, c = 166.16 Å

  5. Fundamentals and applications of neutron diffraction. Applications 7. Crystal structure analysis of fuel cell materials by means of neutron diffractometry

    International Nuclear Information System (INIS)

    Itoh, Takanori

    2010-01-01

    Perovskite oxides, which have 'A' atoms of an alkaline earth metal and/or a rare earth metal and 'B' atoms of a transition metal, have considerable potential for use in electrochemical devices such as cathodes of solid oxide fuel cells (SOFC), oxygen pumps, oxygen sensors, catalysts, and other devices such as oxygen separation membranes. The oxygen ion behavior is studied with relation performance of electrochemical devices. I have analyzed the crystal structure of SOFC materials by neutron diffraction. Using the Rietveld refinement technique, I showed that the O1(4c) and O2(8d) sites in a perovskite oxide of SOFC cathode material has different oxygen site occupancies. Furthermore, oxygen diffusion behavior is associated with temperature dependence of oxygen anisotropic atomic displacement parameters. The maximum entropy method (MEM) analysis of neutron diffraction measurements revealed nuclear scattering length distribution at high temperature by three-dimensional images in detail, therefore 1 found oxygen diffusion pass and new proton site in SOFC materials. From these results, neutron diffraction is confirmed to be very useful tool for the study of light element behavior in fuel cell materials. (author)

  6. Crystallization and preliminary X-ray diffraction analysis of the peptidylprolyl isomerase Par27 of Bordetella pertussis

    International Nuclear Information System (INIS)

    Wohlkönig, Alexandre; Hodak, Hélène; Clantin, Bernard; Sénéchal, Magalie; Bompard, Coralie; Jacob-Dubuisson, Françoise; Villeret, Vincent

    2008-01-01

    Par27 from B. pertussis, the prototype of a new group of parvulins has been crystallized in two different crystal forms. Proteins with both peptidylprolyl isomerase (PPIase) and chaperone activities play a crucial role in protein folding in the periplasm of Gram-negative bacteria. Few such proteins have been structurally characterized and to date only the crystal structure of SurA from Escherichia coli has been reported. Par27, the prototype of a new group of parvulins, has recently been identified. Par27 exhibits both chaperone and PPIase activities in vitro and is the first identified parvulin protein that forms dimers in solution. Par27 has been expressed in E. coli. The protein was purified using affinity and gel-filtration chromatographic techniques and crystallized in two different crystal forms. Form A, which belongs to space group P2 (unit-cell parameters a = 42.2, b = 142.8, c = 56.0 Å, β = 95.1°), diffracts to 2.8 Å resolution, while form B, which belongs to space group C222 (unit-cell parameters a = 54.6, b = 214.1, c = 57.8 Å), diffracts to 2.2 Å resolution. Preliminary diffraction data analysis agreed with the presence of one monomer in the asymmetric unit of the orthorhombic crystal form and two in the monoclinic form

  7. Crystallization and preliminary X-ray diffraction analysis of recombinant hepatitis E virus-like particle

    International Nuclear Information System (INIS)

    Wang, Che-Yen; Miyazaki, Naoyuki; Yamashita, Tetsuo; Higashiura, Akifumi; Nakagawa, Atsushi; Li, Tian-Cheng; Takeda, Naokazu; Xing, Li; Hjalmarsson, Erik; Friberg, Claes; Liou, Der-Ming; Sung, Yen-Jen; Tsukihara, Tomitake; Matsuura, Yoshiharu; Miyamura, Tatsuo; Cheng, R. Holland

    2008-01-01

    A recombinant virus-like particle that is a potential oral hepatitis E vaccine was crystallized. Diffraction data were collected to 8.3 Å resolution and the X-ray structure was phased with the aid of a low-resolution density map determined using cryo-electron microscopy data. Hepatitis E virus (HEV) accounts for the majority of enterically transmitted hepatitis infections worldwide. Currently, there is no specific treatment for or vaccine against HEV. The major structural protein is derived from open reading frame (ORF) 2 of the viral genome. A potential oral vaccine is provided by the virus-like particles formed by a protein construct of partial ORF3 protein (residue 70–123) fused to the N-terminus of the ORF2 protein (residues 112–608). Single crystals obtained by the hanging-drop vapour-diffusion method at 293 K diffract X-rays to 8.3 Å resolution. The crystals belong to space group P2 1 2 1 2 1 , with unit-cell parameters a = 337, b = 343, c = 346 Å, α = β = γ = 90°, and contain one particle per asymmetric unit

  8. Purification, crystallization and preliminary X-ray diffraction analysis of human Gadd45γ

    International Nuclear Information System (INIS)

    Zhang, Wenzheng; Zhao, Mingzhuo; Li, Jianhui; Li, Xuemei; Zeng, ZongHao; Rao, Zihe

    2008-01-01

    The human Gadd45γ protein has been crystallized as a prelude towards determination of its three-dimensional structure by X-ray crystallography. Gadd45, MyD118 and CR6 (also termed Gadd45α, Gadd45β and Gadd45γ, respectively) comprise a family of proteins that play important roles in negative growth control, maintenance of genomic stability, DNA repair, cell-cycle control and apoptosis. Recombinant human Gadd45γ and its selenomethionine derivative were expressed in an Escherichia coli expression system and purified; they were then crystallized using the hanging-drop vapour-diffusion method. Diffraction-quality crystals were grown at 291 K using PEG 3350 as precipitant. Using synchrotron radiation, the best diffraction data were collected to 2.3 Å resolution for native crystals at 100 K; selenomethionyl derivative data were collected to 3.3 Å resolution. All the crystals belonged to space group I2 1 3, with approximate unit-cell parameters a = b = c = 126 Å

  9. High resolution x-ray diffraction analysis of annealed low-temperature gallium arsenide

    Science.gov (United States)

    Matyi, R. J.; Melloch, M. R.; Woodall, J. M.

    1992-05-01

    High resolution x-ray diffraction methods have been used to characterize GaAs grown at low substrate temperatures by molecular beam epitaxy and to examine the effects of post-growth annealing on the structure of the layers. Double crystal rocking curves from the as-deposited epitaxial layer show well-defined interference fringes, indicating a high level of structural perfection despite the presence of excess arsenic. Annealing at temperatures from 700 to 900 °C resulted in a decrease in the perpendicular lattice mismatch between the GaAs grown at low temperature and the substrate from 0.133% to 0.016% and a decrease (but not total elimination) of the visibility of the interference fringes. Triple-crystal diffraction scans around the 004 point in reciprocal space exhibited an increase in the apparent mosaic spread of the epitaxial layer with increasing anneal temperature. The observations are explained in terms of the growth of arsenic precipitates in the epitaxial layer.

  10. Expression, purification, crystallization and preliminary X-ray diffraction analysis of nurse shark β2-microglobulin

    International Nuclear Information System (INIS)

    Lu, Shuangshuang; Yao, Shugang; Chen, Rong; Zhang, Nianzhi; Chen, Jianmin; Gao, Feng; Xia, Chun

    2012-01-01

    A crystal of nurse shark β 2 -microglobulin diffracted to 2.3 Å resolution and belonged to space group P3 2 21, with unit-cell parameters a = b = 88.230, c = 67.146 Å and two molecules per asymmetric unit. The Matthews coefficient V M was calculated to be about 3.28 Å 3 Da −1 , corresponding to 62.5% solvent content. β 2 -Microglobulin (β 2 m) is an essential subunit of the major histocompatibility complex (MHC) class I molecule that helps to stabilize the structure of peptide–MHC I (pMHC I). It is also one of the typical immunoglobulin superfamily (IgSF) molecules in the adaptive immune system (AIS). Sharks belong to the cartilaginous fish, which are the oldest jawed vertebrate ancestors with an AIS to exist in the world. Thus, the study of cartilaginous fish β 2 m would help in understanding the evolution of IgSF molecules. In order to demonstrate this, β 2 m from a cartilaginous fish, nurse shark (Ginglymostoma cirratum), was expressed, refolded, purified and crystallized. Diffraction data were collected to a resolution of 2.3 Å. The crystal belonged to space group P3 2 21, with unit-cell parameters a = b = 88.230, c = 67.146 Å. The crystal structure contained two molecules in the asymmetric unit. The results will provide structural information for study of the evolution of β 2 m and IgSF in the AIS

  11. Crystallization and preliminary X-ray diffraction analysis of Nsp15 from SARS coronavirus

    International Nuclear Information System (INIS)

    Ricagno, Stéfano; Coutard, Bruno; Grisel, Sacha; Brémond, Nicolas; Dalle, Karen; Tocque, Fabienne; Campanacci, Valérie; Lichière, Julie; Lantez, Violaine; Debarnot, Claire; Cambillau, Christian; Canard, Bruno; Egloff, Marie-Pierre

    2006-01-01

    Crystals of Nsp15 from the aetiological agent of SARS have been grown at room temperature. Crystals have cubic symmetry and diffract to a maximum resolution of 2.7 Å. The non-structural protein Nsp15 from the aetiological agent of SARS (severe acute respiratory syndrome) has recently been characterized as a uridine-specific endoribonuclease. This enzyme plays an essential role in viral replication and transcription since a mutation in the related H229E human coronavirus nsp15 gene can abolish viral RNA synthesis. SARS full-length Nsp15 (346 amino acids) has been cloned and expressed in Escherichia coli with an N-terminal hexahistidine tag and has been purified to homogeneity. The protein was subsequently crystallized using PEG 8000 or 10 000 as precipitants. Small cubic crystals of the apoenzyme were obtained from 100 nl nanodrops. They belong to space group P4 1 32 or P4 3 32, with unit-cell parameters a = b = c = 166.8 Å. Diffraction data were collected to a maximum resolution of 2.7 Å

  12. Analysis of Heuristic Uniform Theory of Diffraction Coefficients for Electromagnetic Scattering Prediction

    Directory of Open Access Journals (Sweden)

    Diego Tami

    2018-01-01

    Full Text Available We discuss three sets of heuristic coefficients used in uniform theory of diffraction (UTD to characterize the electromagnetic scattering in realistic urban scenarios and canonical examples of diffraction by lossy conducting wedges using the three sets of heuristic coefficients and the Malyuzhinets solution as reference model. We compare not only the results of the canonical models but also their implementation in real outdoor scenarios. To predict the coverage of mobile networks, we used propagation models for outdoor environments by using a 3D ray-tracing model based on a brute-force algorithm for ray launching and a propagation model based on image theory. To evaluate each set of coefficients, we analyzed the mean and standard deviation of the absolute error between estimates and measured data in Ottawa, Canada; Valencia, Spain; and Cali, Colombia. Finally, we discuss the path loss prediction for each set of heuristic UTD coefficients in outdoor environment, as well as the comparison with the canonical results.

  13. Crystallization and preliminary X-ray diffraction analysis of the fructofuranosidase from Schwanniomyces occidentalis

    International Nuclear Information System (INIS)

    Polo, Aitana; Álvaro-Benito, Miguel; Fernández-Lobato, María; Sanz-Aparicio, Julia

    2009-01-01

    The invertase from Schwanniomyces occidentalis has been expressed in Saccharomyces cerevisiae, purified and crystallized. The wild-type enzyme was also purified and crystallized and diffraction data were collected to 2.9 Å resolution. Schwanniomyces occidentalis invertase is an extracellular enzyme that releases β-fructose from the nonreducing termini of various β-d-fructofuranoside substrates. Its ability to produce 6-kestose by transglycosylation makes this enzyme an interesting research target for applications in industrial biotechnology. The enzyme has been expressed in Saccharomyces cerevisiae. Recombinant and wild-type forms, which showed different glycosylation patterns, were crystallized by vapour-diffusion methods. Although crystallization trials were conducted on both forms of the protein, crystals suitable for X-ray crystallographic analyses were only obtained from the wild-type enzyme. The crystals belonged to space group P2 1 2 1 2 1 , with unit-cell parameters a = 105.78, b = 119.49, c = 137.68 Å. A diffraction data set was collected using a synchrotron source. Self-rotation function and sedimentation-velocity experiments suggested that the enzyme was dimeric with twofold symmetry

  14. Texture analysis of a friction stir processed 6061-T6 aluminum alloy using neutron diffraction

    International Nuclear Information System (INIS)

    Woo, W.; Choo, H.; Brown, D.W.; Vogel, S.C.; Liaw, P.K.; Feng, Z.

    2006-01-01

    Time-of-flight neutron diffraction was used to investigate the texture changes in friction stir-processed (FSP) 6061-T6 aluminum alloy plates. Two different specimens were prepared with the purpose of separating the effects of frictional heating and severe plastic deformation on the changes of the preferred orientation in the as-received rolled plates: a plate processed with both stirring pin and tool shoulder, i.e., a regular FSP plate subjected to both severe plastic deformation and frictional heating (Case 1); and a plate processed only with the tool shoulder, i.e., subjected mainly to frictional heating (Case 2). The diffraction peak intensities provide insights into the texture variations at various locations across the centerline and through the thickness of the FSP plates. Comparison of the texture variations between Cases 1 and 2 clearly shows that the severe plastic deformation from the stirring pin affects the preferred orientation during the FSP, while heating alone from the tool shoulder has little effect

  15. Crystallization and preliminary X-ray diffraction analysis of human endoplasmic reticulum aminopeptidase 2

    International Nuclear Information System (INIS)

    Ascher, David B.; Polekhina, Galina; Parker, Michael W.

    2012-01-01

    The luminal domain of human endoplasmic reticulum aminopeptidase 2 has been expressed, purified and crystallized. The crystals belonged to the orthorhombic space group P2 1 2 1 2 and diffracted anisotropically to 3.3 Å resolution in the best direction on an in-house source. Endoplasmic reticulum aminopeptidase 2 (ERAP2) is a critical enzyme involved in the final processing of MHC class I antigens. Peptide trimming by ERAP2 and the other members of the oxytocinase subfamily is essential to customize longer precursor peptides in order to fit them to the correct length required for presentation on major histocompatibility complex class I molecules. While recent structures of ERAP1 have provided an understanding of the ‘molecular-ruler’ mechanism of substrate selection, little is known about the complementary activities of its homologue ERAP2 despite their sharing 49% sequence identity. In order to gain insights into the structure–function relationship of the oxytocinase subfamily, and in particular ERAP2, the luminal region of human ERAP2 has been crystallized in the presence of the inhibitor bestatin. The crystals belonged to an orthorhombic space group and diffracted anisotropically to 3.3 Å resolution in the best direction on an in-house X-ray source. A molecular-replacement solution suggested that the enzyme has adopted the closed state as has been observed in other inhibitor-bound aminopeptidase structures

  16. Crystallization and preliminary X-ray diffraction analysis of Nsp15 from SARS coronavirus

    Energy Technology Data Exchange (ETDEWEB)

    Ricagno, Stéfano; Coutard, Bruno; Grisel, Sacha; Brémond, Nicolas; Dalle, Karen; Tocque, Fabienne; Campanacci, Valérie; Lichière, Julie; Lantez, Violaine; Debarnot, Claire; Cambillau, Christian; Canard, Bruno; Egloff, Marie-Pierre, E-mail: marie-pierre.egloff@afmb.univ-mrs.fr [Centre National de la Recherche Scientifique and Universités d’Aix-Marseille I et II, UMR 6098, Architecture et Fonction des Macromolécules Biologiques, Ecole Supérieure d’Ingénieurs de Luminy-Case 925, 163 Avenue de Luminy, 13288 Marseille CEDEX 9 (France)

    2006-04-01

    Crystals of Nsp15 from the aetiological agent of SARS have been grown at room temperature. Crystals have cubic symmetry and diffract to a maximum resolution of 2.7 Å. The non-structural protein Nsp15 from the aetiological agent of SARS (severe acute respiratory syndrome) has recently been characterized as a uridine-specific endoribonuclease. This enzyme plays an essential role in viral replication and transcription since a mutation in the related H229E human coronavirus nsp15 gene can abolish viral RNA synthesis. SARS full-length Nsp15 (346 amino acids) has been cloned and expressed in Escherichia coli with an N-terminal hexahistidine tag and has been purified to homogeneity. The protein was subsequently crystallized using PEG 8000 or 10 000 as precipitants. Small cubic crystals of the apoenzyme were obtained from 100 nl nanodrops. They belong to space group P4{sub 1}32 or P4{sub 3}32, with unit-cell parameters a = b = c = 166.8 Å. Diffraction data were collected to a maximum resolution of 2.7 Å.

  17. Diffraction. Powder, amorphous, liquid

    International Nuclear Information System (INIS)

    Sosnowska, I.M.

    1999-01-01

    Neutron powder diffraction is a unique tool to observe all possible diffraction effects appearing in crystal. High-resolution neutron diffractometers have to be used in this study. Analysis of the magnetic structure of polycrystalline materials requires the use of high-resolution neutron diffraction in the range of large interplanar distances. As distinguished from the double axis diffractometers (DAS), which show high resolution only at small interplanar distances, TOF (time-of-flight) diffractometry offers the best resolution at large interplanar distances. (K.A.)

  18. On the use of logarithmic scales for analysis of diffraction data

    Energy Technology Data Exchange (ETDEWEB)

    Urzhumtsev, Alexandre, E-mail: sacha@igbmc.fr [IGBMC, CNRS-INSERM-UdS, 1 Rue Laurent Fries, BP 10142, 67404 Illkirch (France); Physics Department, University of Nancy, BP 239, Faculté des Sciences et des Technologies, 54506 Vandoeuvre-lès-Nancy (France); Afonine, Pavel V. [Lawrence Berkeley National Laboratory, One Cyclotron Road, BLDG 64R0121, Berkeley, CA 94720 (United States); Adams, Paul D. [Lawrence Berkeley National Laboratory, One Cyclotron Road, BLDG 64R0121, Berkeley, CA 94720 (United States); Department of Bioengineering, University of California Berkeley, Berkeley, CA 94720 (United States); IGBMC, CNRS-INSERM-UdS, 1 Rue Laurent Fries, BP 10142, 67404 Illkirch (France)

    2009-12-01

    Conventional and free R factors and their difference, as well as the ratio of the number of measured reflections to the number of atoms in the crystal, were studied as functions of the resolution at which the structures were reported. When the resolution was taken uniformly on a logarithmic scale, the most frequent values of these functions were quasi-linear over a large resolution range. Predictions of the possible model parameterization and of the values of model characteristics such as R factors are important for macromolecular refinement and validation protocols. One of the key parameters defining these and other values is the resolution of the experimentally measured diffraction data. The higher the resolution, the larger the number of diffraction data N{sub ref}, the larger its ratio to the number N{sub at} of non-H atoms, the more parameters per atom can be used for modelling and the more precise and detailed a model can be obtained. The ratio N{sub ref}/N{sub at} was calculated for models deposited in the Protein Data Bank as a function of the resolution at which the structures were reported. The most frequent values for this distribution depend essentially linearly on resolution when the latter is expressed on a uniform logarithmic scale. This defines simple analytic formulae for the typical Matthews coefficient and for the typically allowed number of parameters per atom for crystals diffracting to a given resolution. This simple dependence makes it possible in many cases to estimate the expected resolution of the experimental data for a crystal with a given Matthews coefficient. When expressed using the same logarithmic scale, the most frequent values for R and R{sub free} factors and for their difference are also essentially linear across a large resolution range. The minimal R-factor values are practically constant at resolutions better than 3 Å, below which they begin to grow sharply. This simple dependence on the resolution allows the prediction of

  19. Elements of seismic imaging and velocity analysis – Forward modeling and diffraction analysis of conventional seismic data from the North Sea

    DEFF Research Database (Denmark)

    Montazeri, Mahboubeh

    2018-01-01

    comprises important oil and gas reservoirs. By application of well-established conventional velocity analysis methods and high-quality diffraction imaging techniques, this study aims to increase the resolution and the image quality of the seismic data. In order to analyze seismic wave propagation......-outs and salt delineations, which can be extracted from the diffractions. The potential of diffraction imaging techniques was studied for 2D seismic stacked data from the North Sea. In this approach, the applied plane-wave destruction method was successful in order to suppress the reflections from the stacked....... This improved seismic imaging is demonstrated for a salt structure as well as for Overpressured Shale structures and the Top Chalk of the North Sea....

  20. Purification, crystallization and X-ray diffraction analysis of human dynamin-related protein 1 GTPase-GED fusion protein

    International Nuclear Information System (INIS)

    Klinglmayr, Eva; Wenger, Julia; Mayr, Sandra; Bossy-Wetzel, Ella; Puehringer, Sandra

    2012-01-01

    The crystallization and initial diffraction analysis of human Drp1 GTPase-GED fusion protein are reported. The mechano-enzyme dynamin-related protein 1 plays an important role in mitochondrial fission and is implicated in cell physiology. Dysregulation of Drp1 is associated with abnormal mitochondrial dynamics and neuronal damage. Drp1 shares structural and functional similarities with dynamin 1 with respect to domain organization, ability to self-assemble into spiral-like oligomers and GTP-cycle-dependent membrane scission. Structural studies of human dynamin-1 have greatly improved the understanding of this prototypical member of the dynamin superfamily. However, high-resolution structural information for full-length human Drp1 covering the GTPase domain, the middle domain and the GTPase effector domain (GED) is still lacking. In order to obtain mechanistic insights into the catalytic activity, a nucleotide-free GTPase-GED fusion protein of human Drp1 was expressed, purified and crystallized. Initial X-ray diffraction experiments yielded data to 2.67 Å resolution. The hexagonal-shaped crystals belonged to space group P2 1 2 1 2, with unit-cell parameters a = 53.59, b = 151.65, c = 43.53 Å, one molecule per asymmetric unit and a solvent content of 42%. Expression of selenomethionine-labelled protein is currently in progress. Here, the expression, purification, crystallization and X-ray diffraction analysis of the Drp1 GTPase-GED fusion protein are presented, which form a basis for more detailed structural and biophysical analysis

  1. Preliminary neutron diffraction analysis of challenging human manganese superoxide dismutase crystals.

    Science.gov (United States)

    Azadmanesh, Jahaun; Trickel, Scott R; Weiss, Kevin L; Coates, Leighton; Borgstahl, Gloria E O

    2017-04-01

    Superoxide dismutases (SODs) are enzymes that protect against oxidative stress by dismutation of superoxide into oxygen and hydrogen peroxide through cyclic reduction and oxidation of the active-site metal. The complete enzymatic mechanisms of SODs are unknown since data on the positions of hydrogen are limited. Here, methods are presented for large crystal growth and neutron data collection of human manganese SOD (MnSOD) using perdeuteration and the MaNDi beamline at Oak Ridge National Laboratory. The crystal from which the human MnSOD data set was obtained is the crystal with the largest unit-cell edge (240 Å) from which data have been collected via neutron diffraction to sufficient resolution (2.30 Å) where hydrogen positions can be observed.

  2. Analysis of macro and micro residual stresses in functionally graded materials by diffraction methods

    CERN Document Server

    Dantz, D; Reimers, W

    1999-01-01

    The residual stress state in microwave sintered metal-ceramic functionally graded materials (FGM) consisting of 8Y-ZrO/sub 2//Ni and 8Y-ZrO/sub 2//NiCr8020, respectively, was analysed by non- destructive diffraction methods. In $9 order to get knowledge of the complete residual stress state in the near surface region as well as in the interior of the material, complementary methods were applied. Whereas the surface was characterised by X-ray techniques using $9 conventional sources, the stresses within the bulk of the material were investigated by means of high energy synchrotron radiation. The stress state was found to obey the differences in the coefficients of thermal expansion $9 (micro-stresses) on the one hand and the inhomogeneous cooling conditions (macrostresses) on the other hand. (7 refs).

  3. Analysis of dislocation loops by means of large-angle convergent beam electron diffraction

    CERN Document Server

    Jäger, C; Morniroli, J P; Jäger, W

    2002-01-01

    Diffusion-induced dislocation loops in GaP and GaAs were analysed by means of large-angle convergent beam electron diffraction (LACBED) and conventional contrast methods of transmission electron microscopy. It is demonstrated that LACBED is perfectly suited for use in analysing dislocation loops. The method combines analyses of the dislocation-induced splitting of Bragg lines in a LACBED pattern for the determination of the Burgers vector with analyses of the loop contrast behaviour in transmission electron microscopy bright-field images during tilt experiments, from which the habit plane of the dislocation loop is determined. Perfect dislocation loops formed by condensation of interstitial atoms or vacancies were found, depending on the diffusion conditions. The loops possess left brace 110 right brace-habit planes and Burgers vectors parallel to (110). The LACBED method findings are compared with results of contrast analyses based on the so-called 'inside-outside' contrast of dislocation loops. Advantages o...

  4. Purification, crystallization and preliminary X-ray diffraction analysis of the glyoxalase II from Leishmania infantum

    International Nuclear Information System (INIS)

    Trincão, José; Sousa Silva, Marta; Barata, Lídia; Bonifácio, Cecília; Carvalho, Sandra; Tomás, Ana Maria; Ferreira, António E. N.; Cordeiro, Carlos; Ponces Freire, Ana; Romão, Maria João

    2006-01-01

    A glyoxalase II from L. infantum was cloned, purified and crystallized and its structure was solved by X-ray crystallography. In trypanosomatids, trypanothione replaces glutathione in all glutathione-dependent processes. Of the two enzymes involved in the glyoxalase pathway, glyoxalase I and glyoxalase II, the latter shows absolute specificity towards trypanothione thioester, making this enzyme an excellent model to understand the molecular basis of trypanothione binding. Cloned glyoxalase II from Leishmania infantum was overexpressed in Escherichia coli, purified and crystallized. Crystals belong to space group C222 1 (unit-cell parameters a = 65.6, b = 88.3, c = 85.2 Å) and diffract beyond 2.15 Å using synchrotron radiation. The structure was solved by molecular replacement using the human glyoxalase II structure as a search model. These results, together with future detailed kinetic characterization using lactoyltrypanothione, should shed light on the evolutionary selection of trypanothione instead of glutathione by trypano-somatids

  5. Neutron diffraction analysis of HRh[P(C6H5)3]4

    International Nuclear Information System (INIS)

    Bau, R.; Stevens, R.C.; McLean, M.; Koetzle, T.F.

    1987-01-01

    We have collected neutron diffraction data on a large single crystal of the title compound. The most surprising result is an extremely short Rh-H distance of 1.31(8) A, presumably caused by steric interactions involving the bulky triphenyl phosphine ligands. Crystallographic details: HRh[P(C 6 H 5 ) 3 ] 4 . 1 / 2 C 6 H 6 crystallizes in the space group Pa3, with a = b = c = 22.776(3) A, Z = 8. Data were collected at the Brookhaven High Flux Beam reactor at a temperature of -23 0 C, λ = 1.15882(7) A -1 . Least-squares refinement (in which the phenyl rings were treated as rigid groups) resulted in an R factor [based on data with f > 4σ(F)] of 0.12 for 914 reflections and 95 parameters. 10 refs

  6. 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.)

  7. 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.

  8. Phase identification and internal stress analysis of steamside oxides on superheater tubes by means of X-ray diffraction

    DEFF Research Database (Denmark)

    Pantleon, Karen; Montgomery, Melanie

    Steamside oxides formed on plant exposed superheated tubes were investigated using X-ray diffraction. Phase identification and stress analysis revealed that on ferritic X20CrMoV12-1 pure Hematite and pure Magnetite formed and both phases are under tensile stress. IN contrast, on austenitic TP347H...... Mn-, Cr- and/or Ni-containing oxides are observed, instead of pure Magnetite, underneath a pure Hematite surface layer. Oxides on the austenitic steel are under compressive stress or even stress-free....

  9. Non-invasive neutron diffraction analysis of marbles from the 'Edificio con Tre Esedre' in Villa Adriana

    International Nuclear Information System (INIS)

    Filabozzi, A.; Andreani, C.; Pietropaolo, A.; De Pascale, M.P.; Gorini, G.; Kockelmann, W.; Chapon, L.C.

    2006-01-01

    Roman marble fragments from the Villa Adriana at Tivoli (Rome) have been characterised by neutron diffraction. This study aimed at distinguishing between different marble types on the basis of the mineral phase compositions and the crystallographic textures. It is demonstrated that on a multi-detector time-offlight neutron diffractometer a quantitative bulk texture analysis can be performed on a stationary marble sample in a matter of minutes. This potentially allows investigating large sample series or bulky, intact marble objects in a completely nondestructive manner. The texture information, along with other structure details, can be used as characterising feature to address questions of attribution and restoration of archaeological marble objects

  10. Crystallization and preliminary X-ray diffraction analysis of HML, a lectin from the red marine alga Hypnea musciformis

    International Nuclear Information System (INIS)

    Nagano, Celso S.; Gallego del Sol, Francisca; Cavada, Benildo S.; Nascimento, Kyria Santiago Do; Nunes, Eudismar Vale; Sampaio, Alexandre H.; Calvete, Juan J.

    2005-01-01

    The crystallization and preliminary X-ray diffraction analysis of a red marine alga lectin isolated from H. musciformis is reported. HML, a lectin from the red marine alga Hypnea musciformis, defines a novel lectin family. Orthorhombic crystals of HML belonging to space group P2 1 2 1 2 1 grew within three weeks at 293 K using the hanging-drop vapour-diffusion method. A complete data set was collected at 2.4 Å resolution. HML is the first marine alga lectin to be crystallized

  11. A non-invasive analysis of 'proto-majolica' pottery from southern Italy by TOF neutron diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Barilaro, D; Crupi, V; Majolino, D; Venuti, V [Dipartimento di Fisica, Universita di Messina, Contrada da Papardo, Salita Sperone 31, PO Box 55, 98166, Sant Agata, Messina (Italy); Barone, G [Dipartmento di Scienze Geologiche, Universita di Catania, Corso Italia 55, 95129 Catania (Italy); Tigano, G [Soprintendenza Beni Culturali ed Ambientali di Messina, Sezione Archeologica, Viale Boccetta 38, 98100 Messina (Italy); Imberti, S [Consiglio Nazionale delle Ricerche, Istituto Sistemi Complessi: Sezione di Firenze, Via Madonna del Piano 10, 50019 Sesto Fiorentino (Italy); Kockelmann, W [ISIS Facility, Rutherford Appleton Laboratory, Didcot OX11 0QX (United Kingdom)], E-mail: vvenuti@unime.it

    2008-03-12

    The employment of time-of-flight (TOF) neutron diffraction allowed for the quantitative determination of mineral phase contents of the ceramic bulk of several pottery fragments coming from Milazzo and Messina (Sicily, southern Italy). From an historical-artistic point of view, all the samples were dated back to the 12th to 13th centuries AD and classified as belonging to the 'proto-majolica' ceramic class. The adopted procedure is absolutely non-destructive, so that measurements were performed on the entire fragments without any sampling. The information derived, by applying the Rietveld analysis method, allowed us to formulate hypotheses concerning the fabrication processes of the artefacts.

  12. Spot profile analysis and lifetime mapping in ultrafast electron diffraction: Lattice excitation of self-organized Ge nanostructures on Si(001

    Directory of Open Access Journals (Sweden)

    T. Frigge

    2015-05-01

    Full Text Available Ultrafast high energy electron diffraction in reflection geometry is employed to study the structural dynamics of self-organized Germanium hut-, dome-, and relaxed clusters on Si(001 upon femtosecond laser excitation. Utilizing the difference in size and strain state the response of hut- and dome clusters can be distinguished by a transient spot profile analysis. Surface diffraction from {105}-type facets provide exclusive information on hut clusters. A pixel-by-pixel analysis of the dynamics of the entire diffraction pattern gives time constants of 40, 160, and 390 ps, which are assigned to the cooling time constants for hut-, dome-, and relaxed clusters.

  13. Quantitative study of Portland cement hydration by X-ray diffraction/Rietveld analysis and independent methods

    International Nuclear Information System (INIS)

    Scrivener, K.L.; Fuellmann, T.; Gallucci, E.; Walenta, G.; Bermejo, E.

    2004-01-01

    X-ray diffraction (XRD) is a powerful technique for the study of crystalline materials. The technique of Rietveld refinement now enables the amounts of different phases in anhydrous cementitious materials to be determined to a good degree of precision. This paper describes the extension of this technique to a pilot study of the hydration of a typical Portland cement. To validate this XRD-Rietveld analysis technique, its results were compared with independent measures of the same materials by the analysis of backscattered electron images (BSE/IA) and thermogravimetric analysis (TGA). In addition, the internal consistency of the measurements was studied by comparing the XRD estimates of the amounts of hydrates formed with the amounts expected to form from the XRD estimates of the amounts of anhydrous materials reacted

  14. Diffraction at TOTEM

    CERN Document Server

    Antchev, G.; Avati, V.; Bagliesi, M.G.; Berardi, V.; Berretti, M.; Bottigli, U.; Bozzo, M.; Brucken, E.; Buzzo, A.; Cafagna, F.; Calicchio, M.; Catanesi, M.G.; Catastini, P.L.; Cecchi, R.; Ciocci, M.A.; Deile, M.; Dimovasili, E.; Eggert, K.; Eremin, V.; Ferro, F.; Garcia, F.; Giani, S.; Greco, V.; Heino, J.; Hilden, T.; Kaspar, J.; Kopal, J.; Kundrat, V.; Kurvinen, K.; Lami, S.; Latino, G.; Lauhakangas, R.; Lippmaa, E.; Lokajicek, M.; Lo Vetere, M.; Lucas Rodriguez, F.; Macri, M.; Magazzu, G.; Meucci, M.; Minutoli, S.; Niewiadomski, H.; Noschis, E.; Notarnicola, G.; Oliveri, E.; Oljemark, F.; Orava, R.; Oriunno, M.; Osterberg, K.; Palazzi, P.; Pedreschi, E.; Petajajarvi, J.; Quinto, M.; Radermacher, E.; Radicioni, E.; Ravotti, F.; Rella, G.; Robutti, E.; Ropelewski, L.; Ruggiero, G.; Rummel, A.; Saarikko, H.; Sanguinetti, G.; Santroni, A.; Scribano, A.; Sette, G.; Snoeys, W.; Spinella, F.; Squillacioti, P.; Ster, A.; Taylor, C.; Trummal, A.; Turini, N.; Whitmore, J.; Wu, J.

    2009-01-01

    The TOTEM experiment at the LHC measures the total proton-proton cross section with the luminosity-independent method and the elastic proton-proton cross-section over a wide |t|-range. It also performs a comprehensive study of diffraction, spanning from cross-section measurements of individual diffractive processes to the analysis of their event topologies. Hard diffraction will be studied in collaboration with CMS taking advantage of the large common rapidity coverage for charged and neutral particle detection and the large variety of trigger possibilities even at large luminosities. TOTEM will take data under all LHC beam conditions including standard high luminosity runs to maximize its physics reach. This contribution describes the main features of the TOTEM physics programme including measurements to be made in the early LHC runs. In addition, a novel scheme to extend the diffractive proton acceptance for high luminosity runs by installing proton detectors at IP3 is described.

  15. Diffraction at TOTEM

    CERN Document Server

    Giani, S; Antchev, G; Aspell, P; Avati, V; Bagliesi, M G; Berardi, V; Berretti, M; Besta, M; Bozzo, M; Brücken, E; Buzzo, A; Cafagna, F; Calicchio, M; Catanesi, M G; Cecchi, R; Ciocci, M A; Dadel, P; Deile, M; Dimovasili, E; Eggert, K; Eremin, V; Ferro, F; Fiergolski, A; García, F; Greco, V; Grzanka, L; Heino, J; Hildén, T; Kaspar, J; Kopal, J; Kundrát, V; Kurvinen, K; Lami, S; Latino, G; Lauhakangas, R; Leszko, R; Lippmaa, E; Lokajícek, M; Lo Vetere, M; Lucas Rodriguez, F; Macrí, M; Magazzù, G; Meucci, M; Minutoli, S; Notarnicola, G; Oliveri, E; Oljemark, F; Orava, R; Oriunno, M; Österberg, K; Pedreschi, E; Petäjäjärvi, J; Prochazka, J; Quinto, M; Radermacher, E; Radicioni, E; Ravotti, F; Rella, G; Robutti, E; Ropelewski, L; Rostkowski, M; Ruggiero, G; Rummel, A; Saarikko, H; Sanguinetti, G; Santroni, A; Scribano, A; Sette, G; Snoeys, W; Spinella, F; Ster, A; Taylor, C; Trummal, A; Turini, N; Whitmore, J; Wu, J; Zalewski, M

    2010-01-01

    The primary objective of the TOTEM experiment at the LHC is the measurement of the total proton-proton cross section with the luminosity-independent method and the study of elastic proton-proton cross-section over a wide |t|-range. In addition TOTEM also performs a comprehensive study of diffraction, spanning from cross-section measurements of individual diffractive processes to the analysis of their event topologies. Hard diffraction will be studied in collaboration with CMS taking advantage of the large common rapidity coverage for charged and neutral particle detection and the large variety of trigger possibilities even at large luminosities. TOTEM will take data under all LHC beam conditions including standard high luminosity runs to maximise its physics reach. This contribution describes the main features of the TOTEM diffractive physics programme including measurements to be made in the early LHC runs.

  16. Residual stress analysis in linear friction welded in-service Inconel 718 superalloy via neutron diffraction and contour method approaches

    Energy Technology Data Exchange (ETDEWEB)

    Smith, M. [University of British Columbia – Okanagan, School of Engineering, 3333 University Way, Kelowna, Canada V1V 1V7 (Canada); Levesque, J.-B. [Institut de recherche d' Hydro-Québec (IREQ), 1800 Lionel-Boulet Blvd., Varennes, Canada J3X 1S1 (Canada); Bichler, L., E-mail: lukas.bichler@ubc.ca [University of British Columbia – Okanagan, School of Engineering, 3333 University Way, Kelowna, Canada V1V 1V7 (Canada); Sediako, D. [Canadian Nuclear Laboratories, Building 459, Station 18, Chalk River, Canada K0J 1J0 (Canada); Gholipour, J.; Wanjara, P. [National Research Council of Canada, Aerospace 5145 Decelles Ave., Montreal, Canada H3T 2B2 (Canada)

    2017-04-13

    In this study, an analysis of elastic residual stress in Inconel{sup ®} 718 (IN 718) linear friction welds (LFWs) was carried out. In particular, the suitability of LFW for manufacturing and repair of aero engine components was emulated by joining virgin and in-service (extracted from a turbine disk) materials. The evolution in the residual strains and stresses in the heat-affected zone (HAZ), thermomechanically affected zone (TMAZ) and dynamically recrystallized zone (DRX) of the weld was characterized using the neutron diffraction and contour methods. The results provided insight into diverse challenges in quantitative analysis of residual stresses in welded IN 718 using diffraction techniques. Specifically, judicious selection of the beam width, height and stress-free lattice spacing were seen to be crucial to minimize measurement error and increase accuracy. Further, the contour method – a destructive technique relying on capturing the stress relaxation after electrical discharge machining – was used to characterize the residual stress distribution on two-dimensional plane sections of the welds. Both techniques suggested an increasing magnitude of residual stress originating from the base metal that reached a peak at the weld interface. Both methods indicated that the peak magnitude of residual stresses were below the yield stress of IN 718.

  17. Crystallization and preliminary X-ray diffraction analysis of three myotoxic phospholipases A2 from Bothrops brazili venom

    International Nuclear Information System (INIS)

    Fernandes, Carlos A. H.; Gartuzo, Elaine C. G.; Pagotto, Ivan; Comparetti, Edson J.; Huancahuire-Vega, Salomón; Ponce-Soto, Luis Alberto; Costa, Tássia R.; Marangoni, Sergio; Soares, Andreimar M.; Fontes, Marcos R. M.

    2012-01-01

    Two myotoxic and noncatalytic Lys49-phospholipases A 2 (braziliantoxin-II and MT-II) and a myotoxic and catalytic phospholipase A 2 (braziliantoxin-III) from B. brazili were crystallized. X-ray diffraction data sets were collected and molecular-replacement solutions were obtained. Two myotoxic and noncatalytic Lys49-phospholipases A 2 (braziliantoxin-II and MT-II) and a myotoxic and catalytic phospholipase A 2 (braziliantoxin-III) from the venom of the Amazonian snake Bothrops brazili were crystallized. The crystals diffracted to resolutions in the range 2.56–2.05 Å and belonged to space groups P3 1 21 (braziliantoxin-II), P6 5 22 (braziliantoxin-III) and P2 1 (MT-II). The structures were solved by molecular-replacement techniques. Both of the Lys49-phospholipases A 2 (braziliantoxin-II and MT-II) contained a dimer in the asymmetric unit, while the Asp49-phospholipase A 2 braziliantoxin-III contained a monomer in its asymmetric unit. Analysis of the quaternary assemblies of the braziliantoxin-II and MT-II structures using the PISA program indicated that both models have a dimeric conformation in solution. The same analysis of the braziliantoxin-III structure indicated that this protein does not dimerize in solution and probably acts as a monomer in vivo, similar to other snake-venom Asp49-phospholipases A 2

  18. Expression, purification, crystallization and preliminary X-ray diffraction analysis of nurse shark β2-microglobulin.

    Science.gov (United States)

    Lu, Shuangshuang; Yao, Shugang; Chen, Rong; Zhang, Nianzhi; Chen, Jianmin; Gao, Feng; Xia, Chun

    2012-04-01

    β(2)-Microglobulin (β(2)m) is an essential subunit of the major histocompatibility complex (MHC) class I molecule that helps to stabilize the structure of peptide-MHC I (pMHC I). It is also one of the typical immunoglobulin superfamily (IgSF) molecules in the adaptive immune system (AIS). Sharks belong to the cartilaginous fish, which are the oldest jawed vertebrate ancestors with an AIS to exist in the world. Thus, the study of cartilaginous fish β(2)m would help in understanding the evolution of IgSF molecules. In order to demonstrate this, β(2)m from a cartilaginous fish, nurse shark (Ginglymostoma cirratum), was expressed, refolded, purified and crystallized. Diffraction data were collected to a resolution of 2.3 Å. The crystal belonged to space group P3(2)21, with unit-cell parameters a = b = 88.230, c = 67.146 Å. The crystal structure contained two molecules in the asymmetric unit. The results will provide structural information for study of the evolution of β(2)m and IgSF in the AIS. © 2012 International Union of Crystallography. All rights reserved.

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

    CERN Document Server

    Morelhão, Sérgio Luiz

    2016-01-01

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

  20. Crystallization and preliminary X-ray diffraction analysis of rat protein tyrosine phosphatase η

    Energy Technology Data Exchange (ETDEWEB)

    Matozo, Huita C.; Nascimento, Alessandro S.; Santos, Maria A. M. [Instituto de Física de São Carlos, Departamento de Física e Informática, Universidade de São Paulo, Avenida Trabalhador São Carlense 400, CEP 13566-590 São Carlos, SP (Brazil); Iuliano, Rodolfo [Dipartimento di Medicina Sperimentale e Clinica, Facoltà di Medicina e Chirurgia, Università di Catanzaro, 88100 Catanzaro (Italy); Fusco, Alfredo [Dipartimento di Biologia e Patologia Cellulare e Molecolare, c/o Instituto di Endocrinologia ed Oncologia Sperimentale del CNR, Facolta di Medicina e Chirurgia, Università degli Studi di Napoli ‘Federico II’, Via Pansini 5, 80131 Naples (Italy); NOGEC (Naples Oncogenomocs Center)-CEINGE, Biotecnologie Avanzate, Via Comunale Margherita 482, 80145 Naples (Italy); Polikarpov, Igor, E-mail: ipolikarpov@if.sc.usp.br [Instituto de Física de São Carlos, Departamento de Física e Informática, Universidade de São Paulo, Avenida Trabalhador São Carlense 400, CEP 13566-590 São Carlos, SP (Brazil); Laboratório Nacional de Luz Síncrotron, Campinas, SP (Brazil)

    2006-09-01

    In this study, the catalytic domain of rat protein tyrosine phosphatase η was produced in Escherichia coli in soluble form and purified to homogeneity. Crystals were obtained by the hanging-drop vapour-diffusion method. The rat protein tyrosine phosphatase η (rPTPη) is a cysteine-dependent phosphatase which hydrolyzes phosphoester bonds in proteins and other molecules. rPTPη and its human homologue DEP-1 are involved in neoplastic transformations. Thus, expression of the protein is reduced in all oncogene-transformed thyroid cell lines and is absent in highly malignant thyroid cells. Moreover, consistent with the suggested tumour suppression role of PTPη, inhibition of the tumorigenic process occurs after its exogenous reconstitution, suggesting that PTPη might be important for gene therapy of cancers. In this study, the catalytic domain of rPTPη was produced in Escherichia coli in soluble form and purified to homogeneity. Crystals were obtained by the hanging-drop vapour-diffusion method. Diffraction data were collected to 1.87 Å resolution. The crystal belongs to space group P2{sub 1}2{sub 1}2{sub 1}, with unit-cell parameters a = 46.46, b = 63.07, c = 111.64 Å, and contains one molecule per asymmetric unit.

  1. Crystallization and preliminary X-ray diffraction analysis of motif N from Saccharomyces cerevisiae Dbf4

    International Nuclear Information System (INIS)

    Matthews, Lindsay A.; Duong, Andrew; Prasad, Ajai A.; Duncker, Bernard P.; Guarné, Alba

    2009-01-01

    To understand the role of the Cdc7–Dbf4 complex in checkpoint responses, a fragment of Saccharomyces cerevisiae Dbf4 encompassing motif N was isolated, overproduced and crystallized. The Cdc7–Dbf4 complex plays an instrumental role in the initiation of DNA replication and is a target of replication-checkpoint responses in Saccharomyces cerevisiae. Cdc7 is a conserved serine/threonine kinase whose activity depends on association with its regulatory subunit, Dbf4. A conserved sequence near the N-terminus of Dbf4 (motif N) is necessary for the interaction of Cdc7–Dbf4 with the checkpoint kinase Rad53. To understand the role of the Cdc7–Dbf4 complex in checkpoint responses, a fragment of Saccharomyces cerevisiae Dbf4 encompassing motif N was isolated, overproduced and crystallized. A complete native data set was collected at 100 K from crystals that diffracted X-rays to 2.75 Å resolution and structure determination is currently under way

  2. Expression, purification, crystallization and preliminary X-ray diffraction analysis of grass carp β2-microglobulin

    International Nuclear Information System (INIS)

    Chen, Weihong; Chu, Fuliang; Peng, Hao; Zhang, Jianhua; Qi, Jianxun; Jiang, Fan; Xia, Chun; Gao, Feng

    2008-01-01

    Grass carp β 2 -microglobulin was expressed in E. coli, purified to homogeneity and crystallized using the hanging-drop vapour-diffusion method with PEG 2K as precipitant. The crystals obtained belong to the orthorhombic space group P2 1 2 1 2 1 , with unit-cell parameters a = 38.72, b = 40.65, c = 71.12 Å. β 2 -Microglobulin (β 2 m) is an essential subunit of MHC I molecules; it stabilizes the structure of MHC I and plays a pivotal role in coreceptor recognition. To date, structures of β 2 m have been solved for three different mammals: human, mouse and cattle. In order to illuminate the molecular evolutionary origin of β2m, an understanding of its structure in lower vertebrates becomes important. Here, grass carp (Ctenopharyngodon idellus) β 2 m (Ctid-β 2 m) was expressed, purified and crystallized. Diffraction data were collected to a resolution of 2.5 Å. The crystal belongs to space group P2 1 2 1 2 1 , with unit-cell parameters a = 38.72, b = 40.65, c = 71.12 Å. The Matthews coefficient and the solvent content were calculated to be 2.56 Å Da −1 and 52.07%, respectively, for one molecule per asymmetric unit. The structure has been solved by molecular replacement using monomeric human β 2 m as a model

  3. Electron diffraction analysis of an AB{sub 2}-type Laves phase for hydrogen battery applications

    Energy Technology Data Exchange (ETDEWEB)

    Shi, Z.; Chumbley, S.; Laabs, F.C. [Iowa State Univ., Ames, IA (United States). Ames Lab.

    2000-11-16

    A multicomponent AB{sub 2} type nickel-metal hydride (Ni-MH) battery alloy prepared by high-pressure gas atomization (HPGA) was investigated by transmission electron microscopy (TEM) in both the as-atomized and heat treated condition. TEM examination showed a heavily faulted dendritic growth structure in as-atomized powder. Selected area diffraction (SAD) showed that this region consisted of both a cubic C15 structure with lattice constant a=7.03 A and an hexagonal C14 structure with lattice parameter a=4.97 A, c=8.11 A. The orientation relationship (OR) between the C14 and C15 structures was determined to be (111)[1 anti 10]{sub C15}//(0001)[11 anti 20]C{sub 14}. An interdendritic phase possessing the C14 structure was also seen. There was also a very fine grain region consisting of the C14 structure. Upon heat treatment, the faulted structure became more defined and appeared as intercalation layers within the grains. Spherical particles rich in Zr and Ni appeared scattered at the grain boundries instead of the C14 interdendritic phase. The polycrystalline region also changed to a mixture of C14 and C15 structures. The phase stability of the C15 and C14 structures based on a consideration of atomic size factor and the average electron concentration is discussed. (orig.)

  4. X-ray diffraction analysis of a severely plastically deformed aluminum alloy

    International Nuclear Information System (INIS)

    Ortiz, A.L.; Shaw, L.

    2004-01-01

    The crystallite size, lattice microstrain, lattice parameter, and formation of solid solutions of a nanocrystalline Al 93 Fe 3 Cr 2 Ti 2 alloy prepared via mechanical alloying (MA) starting from elemental powders have been investigated using the Rietveld method of X-ray diffraction (XRD) in conjunction with line-broadening analyses through the variance, Warren-Averbach, and Stokes and Wilson methods. Detailed analyses using transmission electron microscopy (TEM), scanning electron microscopy (SEM), and inductively coupled plasma-optical emission spectroscopy (ICP) have also been conducted in order to corroborate the formation of solid solutions and the grain size measurement determined from the XRD analyses. The results from the exhaustive XRD analyses are in excellent agreement with those derived from the investigation of TEM, SEM, and ICP. The lattice microstrains of the nanocrystalline Al solid solution determined from the XRD analyses are isotropic along different crystallographic directions and high, exhibiting the same order of magnitude as the ratio of the tensile strength to the elastic modulus of the Al crystal. Implications resulting from the comparison between the present study and the simplified XRD analyses are discussed

  5. Analysis of soft magnetic materials by electron backscatter diffraction as a powerful tool

    Directory of Open Access Journals (Sweden)

    David Schuller

    2018-04-01

    Full Text Available The current work demonstrates that electron backscatter diffraction (EBSD is a powerful and versatile characterization technique for investigating soft magnetic materials. The properties of soft magnets, e.g., magnetic losses strongly depend on the materials chemical composition and microstructure, including grain size and shape, texture, degree of plastic deformation and elastic strain. In electrical sheet stacks for e-motor applications, the quality of the machined edges/surfaces of each individual sheet is of special interest. Using EBSD, the influence of the punching process on the microstructure at the cutting edge is quantitatively assessed by evaluating the crystallographic misorientation distribution of the deformed grains. Using an industrial punching process, the maximum affected deformation depth is determined to be 200 - 300 μm. In the case of laser cutting, the affected deformation depth is determined to be approximately zero. Reliability and detection limits of the developed EBSD approach are evaluated on non-affected sample regions and model samples containing different indentation test bodies. A second application case is the investigation of the recrystallization process during the annealing step of soft magnetic composites (SMC toroids produced by powder metallurgy as a function of compaction pressure, annealing parameters and powder particle size. With increasing pressure and temperature, the recrystallized area fraction (e.g., grains with crystallographic misorientations 3°.

  6. Crystallization and diffraction analysis of the SARS coronavirus nsp10–nsp16 complex

    International Nuclear Information System (INIS)

    Debarnot, Claire; Imbert, Isabelle; Ferron, François; Gluais, Laure; Varlet, Isabelle; Papageorgiou, Nicolas; Bouvet, Mickaël; Lescar, Julien; Decroly, Etienne; Canard, Bruno

    2011-01-01

    The expression, purification and crystallization of the SARS coronavirus nsp16 RNA-cap AdoMet-dependent (nucleoside-2′O)-methyltransferase in complex with its activating factor nsp10 are reported. To date, the SARS coronavirus is the only known highly pathogenic human coronavirus. In 2003, it was responsible for a large outbreak associated with a 10% fatality rate. This positive RNA virus encodes a large replicase polyprotein made up of 16 gene products (nsp1–16), amongst which two methyltransferases, nsp14 and nsp16, are involved in viral mRNA cap formation. The crystal structure of nsp16 is unknown. Nsp16 is an RNA-cap AdoMet-dependent (nucleoside-2′-O-)-methyltransferase that is only active in the presence of nsp10. In this paper, the expression, purification and crystallization of nsp10 in complex with nsp16 are reported. The crystals diffracted to a resolution of 1.9 Å resolution and crystal structure determination is in progress

  7. Crystal structure and charge density analysis of Li2NH by synchrotron X-ray diffraction

    International Nuclear Information System (INIS)

    Noritake, T.; Nozaki, H.; Aoki, M.; Towata, S.; Kitahara, G.; Nakamori, Y.; Orimo, S.

    2005-01-01

    Complex hydrides, such as lithium amide (LiNH 2 ) and lithium imide (Li 2 NH), have recently been noticed as one of the most promising materials for reversible hydrogen storage. In this paper, we reveal the bonding nature of hydrogen in Li 2 NH crystal by synchrotron powder X-ray diffraction measurement at room temperature. The crystal structure was refined by Rietveld method and the charge density distribution was analyzed by maximum entropy method (MEM). The Li 2 NH crystal is anti-fluorite type structure (space group Fm3-bar m) consisting of Li and NH. Hydrogen atom occupies randomly the 48h (Wyckoff notation) sites around N atom. The refined lattice constant is a=5.0742(2)A. The charge density distribution around NH anion in Li 2 NH is almost spherical. The number of electrons within the sphere around the Li and NH is estimated from the obtained charge density distribution. As the result, the ionic charge is expressed as [Li 0.99+ ] 2 [NH] 1.21- . Therefore, it is confirmed experimentally that Li 2 NH is ionically bonded

  8. X-ray diffraction analysis of cubic zincblende III-nitrides

    International Nuclear Information System (INIS)

    Frentrup, Martin; Lee, Lok Yi; Sahonta, Suman-Lata; Kappers, Menno J; Massabuau, Fabien; Gupta, Priti; Oliver, Rachel A; Humphreys, Colin J; Wallis, David J

    2017-01-01

    Solving the green gap problem is a key challenge for the development of future LED-based light systems. A promising approach to achieve higher LED efficiencies in the green spectral region is the growth of III-nitrides in the cubic zincblende phase. However, the metastability of zincblende GaN along with the crystal growth process often lead to a phase mixture with the wurtzite phase, high mosaicity, high densities of extended defects and point defects, and strain, which can all impair the performance of light emitting devices. X-ray diffraction (XRD) is the main characterization technique to analyze these device-relevant structural properties, as it is very cheap in comparison to other techniques and enables fast feedback times. In this review, we will describe and apply various XRD techniques to identify the phase purity in predominantly zincblende GaN thin films, to analyze their mosaicity, strain state, and wafer curvature. The different techniques will be illustrated on samples grown by metalorganic vapor phase epitaxy on pieces of 4″ SiC/Si wafers. We will discuss possible issues, which may arise during experimentation, and provide a critical view on the common theories. (topical review)

  9. Morphometric analysis of erythrocytes from patients with thalassemia using tomographic diffractive microscopy

    Science.gov (United States)

    Lin, Yang-Hsien; Huang, Shin-Shyang; Wu, Shang-Ju; Sung, Kung-Bin

    2017-11-01

    Complete blood count is the most common test to detect anemia, but it is unable to obtain the abnormal shape of erythrocytes, which highly correlates with the hematologic function. Tomographic diffractive microscopy (TDM) is an emerging technique capable of quantifying three-dimensional (3-D) refractive index (RI) distributions of erythrocytes without labeling. TDM was used to characterize optical and morphological properties of 172 erythrocytes from healthy volunteers and 419 erythrocytes from thalassemic patients. To efficiently extract and analyze the properties of erythrocytes, we developed an adaptive region-growing method for automatically delineating erythrocytes from 3-D RI maps. The thalassemic erythrocytes not only contained lower hemoglobin content but also showed doughnut shape and significantly lower volume, surface area, effective radius, and average thickness. A multi-indices prediction model achieved perfect accuracy of diagnosing thalassemia using four features, including the optical volume, surface-area-to-volume ratio, sphericity index, and surface area. The results demonstrate the ability of TDM to provide quantitative, hematologic measurements and to assess morphological features of erythrocytes to distinguish healthy and thalassemic erythrocytes.

  10. Crystallization and preliminary X-ray diffraction analysis of rat protein tyrosine phosphatase η

    International Nuclear Information System (INIS)

    Matozo, Huita C.; Nascimento, Alessandro S.; Santos, Maria A. M.; Iuliano, Rodolfo; Fusco, Alfredo; Polikarpov, Igor

    2006-01-01

    In this study, the catalytic domain of rat protein tyrosine phosphatase η was produced in Escherichia coli in soluble form and purified to homogeneity. Crystals were obtained by the hanging-drop vapour-diffusion method. The rat protein tyrosine phosphatase η (rPTPη) is a cysteine-dependent phosphatase which hydrolyzes phosphoester bonds in proteins and other molecules. rPTPη and its human homologue DEP-1 are involved in neoplastic transformations. Thus, expression of the protein is reduced in all oncogene-transformed thyroid cell lines and is absent in highly malignant thyroid cells. Moreover, consistent with the suggested tumour suppression role of PTPη, inhibition of the tumorigenic process occurs after its exogenous reconstitution, suggesting that PTPη might be important for gene therapy of cancers. In this study, the catalytic domain of rPTPη was produced in Escherichia coli in soluble form and purified to homogeneity. Crystals were obtained by the hanging-drop vapour-diffusion method. Diffraction data were collected to 1.87 Å resolution. The crystal belongs to space group P2 1 2 1 2 1 , with unit-cell parameters a = 46.46, b = 63.07, c = 111.64 Å, and contains one molecule per asymmetric unit

  11. Neutron irradiated uranium silicides studied by neutron diffraction and Rietveld analysis

    International Nuclear Information System (INIS)

    Birtcher, R.C.; Mueller, M.H.; Richardson, J.W. Jr.; Faber, J. Jr.

    1989-11-01

    Uranium silicides have been considered for use as reactor fuels in both high power and low enrichment applications. However, U 3 Si was found to become amorphous under irradiation and to become mechanically unstable to rapid growth by plastic flow. U 2 Si 2 appears to be stable against amorphization at low displacement rates, but the extent of this stability is uncertain. Although the mechanisms responsible for plastic flow in U 3 Si and other amorphous systems are unknown, as is the importance of crystal structure for amorphization, it may not be surprising that these materials amorphize, in light of the fact that many radioactive nuclide - containing minerals are known to metaminctize (lose crystallinity) under irradiation. The present experiment follows the detailed changes in the crystal structures of U 3 Si and U 3 Si 2 introduced by neutron bombardment and subsequent uranium fission at room temperature. U-Si seems the ideal system for a neutron diffraction investigation since the crystallographic and amorphous forms can be studied simultaneously by combining conventional Rietveld refinement of the crystallographic phases with Fourier-filtering of the non-crystalline scattering component

  12. Quantitative phase analysis of alumina/calcium-hexaluminate composites using neutron diffraction data and the Rietveld method

    International Nuclear Information System (INIS)

    Asmi, D.; Low, I.M.; O'Connor, B.H.; Kennedy, S.J.

    2000-01-01

    Full text: The Al 2 O 3 -CaO system is the basis of an important class of high-temperature refractories in the steel industry. It contains a number of stable intermediate compounds which include C 3 A, C 12 A 7 , CA, CA 2 , and CA 6 . These calcium aluminates are also important constituents of high alumina cement and have been used to produce high-strength and high-toughness ceramic-polymer composite materials. More recently, alumina composites containing 30 wt% CA 6 platelets have been developed by An et al which show characteristics of self-reinforcement and enhanced toughening through crack-bridging. In this paper, we describe the use of high-temperature neutron diffraction to monitor the in-situ phase formation and abundances of calcium aluminates (CA, CA 2 , and CA 6 ) in alumina composites containing 5-50 wt % CA 6 .at temperatures in the range 1000 - 1600 deg C. These composites were produced using reaction sintering of alumina and calcium oxide. For comparison purposes, control samples of pure α-alumina and CA 6 were also produced. Determination of relative phase abundances in these materials has been performed using the standardless Rietveld refinement method. Results show that the relative phase abundance of calcium aluminates in the composites increased with temperature and in proportion with the amount of calcium oxide present. The formation temperatures of CA, CA 2 , and CA 6 have been observed to occur at 1000 deg , 1200 deg, and ∼1350 deg C respectively, which agree well with results obtained from x-ray diffraction, synchrotron radiation diffraction and differential thermal analysis

  13. Chemical and X-ray diffraction analysis on selected samples from the TMI-2 reactor core

    International Nuclear Information System (INIS)

    Kleykamp, H.; Pejsa, R.

    1991-05-01

    Selected samples from different positions of the damaged TMI-2 reactor core were investigated by X-ray microanalysis and X-ray diffraction. The measurements yield the following resolidified phases after cooling: Cd and In depleted Ag absorber material, intermetallic Zr-steel compounds, fully oxidized Zircaloy, UO 2 -ZrO 2 solid solutions and their decomposed phases, and Fe-Al-Cr-Zr spinels. The composition of the phases and their lattice parameters as well as the eutectic and monotectic character can serve as indicators of local temperatures of the core. The reaction sequences are estimated from the heterogeneous equilibria of these phases. The main conclusions are: (1) Liquefaction onset is locally possible by Inconel-Zircaloy and steel-Zircaloy reactions of spacers and absorber guide tubes at 930deg C. However, increased rates of dissolution occur above 1200deg C. (2) UO 2 dissolution in the Inconel-steel-Zircaloy melt starts at 1300deg C with increased rates above 1900deg C. (3) Fuel temperatures in the core centre are increased above 2550deg C, liquid (U,Zr)O 2 is generated. (4) Square UO 2 particles are reprecipitated from the Incoloy-steel-Zircaloy-UO 2 melt during cooling, the remaining metallic melt is oxygen poor; two types of intermetallic phases are formed. (5) Oxidized Fe and Zr and Al 2 O 3 from burnable absorber react to spinels which form a low melting eutectic with the fuel at 1500deg C. The spinel acts as lubricant for fuel transport to the lower reactor plenum above 1500deg C. (6) Ruthenium (Ru-106) is dissolved in the steel phase, antimony (Sb-125) in the α-Ag absorber during liquefaction. (7) Oxidation of the Zircaloy-steel phases takes place mainly in the reflood stage 3 of the accident scenario. (orig.) [de

  14. Analysis of soft magnetic materials by electron backscatter diffraction as a powerful tool

    Science.gov (United States)

    Schuller, David; Hohs, Dominic; Loeffler, Ralf; Bernthaler, Timo; Goll, Dagmar; Schneider, Gerhard

    2018-04-01

    The current work demonstrates that electron backscatter diffraction (EBSD) is a powerful and versatile characterization technique for investigating soft magnetic materials. The properties of soft magnets, e.g., magnetic losses strongly depend on the materials chemical composition and microstructure, including grain size and shape, texture, degree of plastic deformation and elastic strain. In electrical sheet stacks for e-motor applications, the quality of the machined edges/surfaces of each individual sheet is of special interest. Using EBSD, the influence of the punching process on the microstructure at the cutting edge is quantitatively assessed by evaluating the crystallographic misorientation distribution of the deformed grains. Using an industrial punching process, the maximum affected deformation depth is determined to be 200 - 300 μm. In the case of laser cutting, the affected deformation depth is determined to be approximately zero. Reliability and detection limits of the developed EBSD approach are evaluated on non-affected sample regions and model samples containing different indentation test bodies. A second application case is the investigation of the recrystallization process during the annealing step of soft magnetic composites (SMC) toroids produced by powder metallurgy as a function of compaction pressure, annealing parameters and powder particle size. With increasing pressure and temperature, the recrystallized area fraction (e.g., grains with crystallographic misorientations particle boundaries or areas with existing plastic deformation. The progress of recrystallization is visualized as a function of time and of different particle to grain size distributions. Here, large particles with coarse internal grain structures show a favorable recrystallization behavior which results in large bulk permeability of up to 600 - 700 and lower amount of residual misorientations (>3°).

  15. Analysis of Arbitrary Reflector Antennas Applying the Geometrical Theory of Diffraction Together with the Master Points Technique

    Directory of Open Access Journals (Sweden)

    María Jesús Algar

    2013-01-01

    Full Text Available An efficient approach for the analysis of surface conformed reflector antennas fed arbitrarily is presented. The near field in a large number of sampling points in the aperture of the reflector is obtained applying the Geometrical Theory of Diffraction (GTD. A new technique named Master Points has been developed to reduce the complexity of the ray-tracing computations. The combination of both GTD and Master Points reduces the time requirements of this kind of analysis. To validate the new approach, several reflectors and the effects on the radiation pattern caused by shifting the feed and introducing different obstacles have been considered concerning both simple and complex geometries. The results of these analyses have been compared with the Method of Moments (MoM results.

  16. A X-ray diffraction analysis on constituent distribution of heavy rust layer formed on weathering steel using synchrotron radiation

    International Nuclear Information System (INIS)

    Hara, Shuichi

    2008-01-01

    A local structural analysis of heavy rust layers with large swelling and laminated layers formed on weathering steel bridges using synchrotron radiation X-ray diffraction (SR-XRD) in SPring-8 have been performed. The main constituent in average composition of the whole layer was spinel-type iron oxide [mainly Magnetite (Fe 3 O 4 )] and the mass ratio was 30-40 mass%. In contrast the mass ratio of spinel in its local parts, i.e., outer layer, inter-layer and inner layer position was not higher in common but the mass ratio of β-FeOOH was higher. Therefore it indicates that these heavy rust layers have been composed of many layers of spinel poor, rich and poor - cell (SPRaP-cell). Thus SR-XRD is useful for the analysis of the constituent distribution in the rust layer. (author)

  17. Time-resolved x-ray diffraction analysis of the experimental dehydration of serpentine at high pressure

    International Nuclear Information System (INIS)

    Inoue, Toru; Yoshimi, Isamu; Yamada, Akihiro; Kikegawa, Takumi

    2009-01-01

    Time-resolved, in situ X-ray diffraction analysis was used to determine the dehydration rate and kinetics of serpentine during experimental dehydration at high pressures. The capsule used comprises a diamond sleeve fitted with Au or Pt lids in order to provide high-quality, time-resolved X-ray diffraction data. Antigorite quickly dehydrated to enstatite + forsterite + fluid within 2 h at 650degC below ∼6 GPa. Avrami modeling of the results and SEM observations of the partially dehydrated sample revealed that the nucleation rate was quite high for enstatite but low for forsterite, showing incubation periods of ∼10 min before appearing. The crystallization of these minerals is controlled largely by the composition of the fluid generated from serpentine dehydration. The dehydration boundary determined below 6 GPa in the present study is consistent with the results of previous phase equilibrium studies. This study indicates that serpentine in a subducting slab dehydrates rapidly below 6 GPa when the slab intersects the dehydration boundary conditions. (author)

  18. Crystallization and preliminary X-ray diffraction analysis of a glutathione S-transferase from Xylella fastidiosa

    International Nuclear Information System (INIS)

    Garcia, Wanius; Travensolo, Regiane F.; Rodrigues, Nathalia C.; Muniz, João R. C.; Caruso, Célia S.; Lemos, Eliana G. M.; Araujo, Ana Paula U.; Carrilho, Emanuel

    2008-01-01

    Glutathione S-transferase from X. fastidiosa (xfGST) has been overexpressed in E. coli, purified and crystallized. Diffraction data were collected to 2.23 Å. Glutathione S-transferases (GSTs) form a group of multifunctional isoenzymes that catalyze the glutathione-dependent conjugation and reduction reactions involved in the cellular detoxification of xenobiotic and endobiotic compounds. GST from Xylella fastidiosa (xfGST) was overexpressed in Escherichia coli and purified by conventional affinity chromatography. In this study, the crystallization and preliminary X-ray analysis of xfGST is described. The purified protein was crystallized by the vapour-diffusion method, producing crystals that belonged to the triclinic space group P1. The unit-cell parameters were a = 47.73, b = 87.73, c = 90.74 Å, α = 63.45, β = 80.66, γ = 94.55°. xfGST crystals diffracted to 2.23 Å resolution on a rotating-anode X-ray source

  19. Crystallization and preliminary X-ray diffraction analysis of L,L-diaminopimelate aminotransferase (DapL) from Chlamydomonas reinhardtii.

    Science.gov (United States)

    Hudson, André O; Girón, Irma; Dobson, Renwick C J

    2011-01-01

    In the anabolic synthesis of diaminopimelate and lysine in plants and in some bacteria, the enzyme L,L-diaminopimelate aminotransferase (DapL; EC 2.6.1.83) catalyzes the conversion of tetrahydrodipicolinic acid (THDPA) to L,L-diaminopimelate, bypassing the DapD, DapC and DapE enzymatic steps in the bacterial acyl pathways. Here, the cloning, expression, purification, crystallization and preliminary X-ray diffraction analysis of DapL from the alga Chlamydomonas reinhardtii are presented. Protein crystals were grown in conditions containing 25% (w/v) PEG 3350 and 200 mM lithium sulfate and initially diffracted to ∼1.35 Å resolution. They belonged to space group P2(1)2(1)2(1), with unit-cell parameters a=58.9, b=91.8, c=162.9 Å. The data were processed to 1.55 Å resolution with an Rmerge of 0.081, an Rp.i.m. of 0.044, an Rr.i.m of 0.093 and a VM of 2.28 Å3 Da(-1).

  20. Crystal structure analysis of LaMnO_3 with x-ray diffraction technique using the Rietveld method

    International Nuclear Information System (INIS)

    Engkir Sukirman; Wisnu Ari Adi; Yustinus Purwamargapratala

    2010-01-01

    Crystal structure analysis of LaMnO_3 using the Rietveld method has been carried out. The LaMnO_3 sample was synthesized with high energy mechanical milling from the raw materials of La_2O_3 and MnO_2 with the appropriate mol ratio. Milling were performed for 10 hours, pelletized and hereinafter sintered at 1350 °C for 6 hours. The sample characterizations covered the crystal structure and electric-magnetic properties of the materials by X-ray diffraction technique using the Rietveld method and the four point probe, respectively. The Rietveld refinement results based on the X-rays diffraction data indicate that the sample of LaMnO_3 is single phase with the crystal system: orthorhombic, the space group: Pnma No. 62 and the lattice parameters: a = 55.4405(9) Å; b = 7.717(1) Å dan c = 5.537(1) Å. The material owns Magnetic Resonance (MR) respond of 7 %, the mean value of crystallite size, D = 17 nm and lattice strain, e = - 0.5 %. So, the material go through a compressive strain, and according to the Nanda's strain model, it becomes a type G antiferromagnetic insulator. Because the insulator properties of the material does not change although being hit by the external magnetic field, hence the MR respond is only caused by the order of electron spin. Therefore at room temperature, LaMnO_3_._0 just exhibits a small MR respond. (author)

  1. Crystallization and preliminary X-ray diffraction analysis of a glutathione S-transferase from Xylella fastidiosa

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, Wanius, E-mail: wanius@if.sc.usp.br [Laboratório de Biofísica Molecular ‘Sérgio Mascarenhas’, Instituto de Física de São Carlos, Universidade de São Paulo (USP), São Carlos (Brazil); Travensolo, Regiane F. [Grupo de Bioanalítica, Microfabricação e Separações, Instituto de Química de São Carlos, Universidade de São Paulo (USP), São Carlos (Brazil); Rodrigues, Nathalia C.; Muniz, João R. C. [Laboratório de Biofísica Molecular ‘Sérgio Mascarenhas’, Instituto de Física de São Carlos, Universidade de São Paulo (USP), São Carlos (Brazil); Caruso, Célia S. [Grupo de Bioanalítica, Microfabricação e Separações, Instituto de Química de São Carlos, Universidade de São Paulo (USP), São Carlos (Brazil); Lemos, Eliana G. M. [Laboratório de Bioquímica de Microrganismos e de Plantas, Departamento de Tecnologia, UNESP, Jaboticabal (Brazil); Araujo, Ana Paula U. [Laboratório de Biofísica Molecular ‘Sérgio Mascarenhas’, Instituto de Física de São Carlos, Universidade de São Paulo (USP), São Carlos (Brazil); Carrilho, Emanuel, E-mail: wanius@if.sc.usp.br [Grupo de Bioanalítica, Microfabricação e Separações, Instituto de Química de São Carlos, Universidade de São Paulo (USP), São Carlos (Brazil); Laboratório de Biofísica Molecular ‘Sérgio Mascarenhas’, Instituto de Física de São Carlos, Universidade de São Paulo (USP), São Carlos (Brazil)

    2008-02-01

    Glutathione S-transferase from X. fastidiosa (xfGST) has been overexpressed in E. coli, purified and crystallized. Diffraction data were collected to 2.23 Å. Glutathione S-transferases (GSTs) form a group of multifunctional isoenzymes that catalyze the glutathione-dependent conjugation and reduction reactions involved in the cellular detoxification of xenobiotic and endobiotic compounds. GST from Xylella fastidiosa (xfGST) was overexpressed in Escherichia coli and purified by conventional affinity chromatography. In this study, the crystallization and preliminary X-ray analysis of xfGST is described. The purified protein was crystallized by the vapour-diffusion method, producing crystals that belonged to the triclinic space group P1. The unit-cell parameters were a = 47.73, b = 87.73, c = 90.74 Å, α = 63.45, β = 80.66, γ = 94.55°. xfGST crystals diffracted to 2.23 Å resolution on a rotating-anode X-ray source.

  2. X-Ray Diffraction Profile Analysis for Characterizing Isothermal Aging Behavior of M250 Grade Maraging Steel

    Science.gov (United States)

    Mahadevan, S.; Jayakumar, T.; Rao, B. P. C.; Kumar, Anish; Rajkumar, K. V.; Raj, Baldev

    2008-08-01

    X-ray diffraction (XRD) studies were carried out to characterize aging behavior of M250 grade maraging steel samples subjected to isothermal aging at 755 K for varying durations of 0.25, 1, 3, 10, 40, 70, and 100 hours. Earlier studies had shown typical features of precipitation hardening, wherein the hardness increased to a peak value due to precipitation of intermetallics and decreased upon further aging (overaging) due to reversion of martensite to austenite. Intermetallic precipitates, while coherent, are expected to increase the microstrain in the matrix. Hence, an attempt has been made in the present study to understand the microstructural changes in these samples using XRD line profile analysis. The anisotropic broadening with diffraction angle observed in the simple Williamson Hall (WH) plot has been addressed using the modified WH (mWH) approach, which takes into account the contrast caused by dislocations on line profiles, leading to new scaling factors in the WH plot. The normalized mean square strain and crystallite size estimated from mWH have been used to infer early precipitation and to characterize aging behavior. The normalized mean square strain has been used to determine the Avrami exponent in the Johnson Mehl Avrami (JMA) equation, which deals with the kinetics of precipitation. The Avrami exponent thus determined has matched well with values found by other methods, as reported in literature.

  3. Microstructural analysis of the {delta} to {alpha}' phase transformation in plutonium alloys using X-ray diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Platteau, C; Ravat, B; Texier, G; Oudot, B; Delaunay, F, E-mail: brice.ravat@cea.fr [CEA Valduc 21120 Is sur Tille (France)

    2010-03-15

    The partial martensitic {delta}{yields}{alpha}' transformation in plutonium alloys is sensitive to chemical composition, sample thermal history, as well as crystalline defects. The present work investigates the {delta}-Pu phase microstructure before and after the martensitic transformation {delta}{yields}{delta}+{alpha}'. More precisely, microstructural modifications of the host {delta}-phase, resulting from the stress induced by a cell volume difference of 19% between the {delta} and {alpha}'-phases, were analysed. Microstructural information about crystallite size and microstrain of a highly homogenized Pu-Ga alloy was extracted from x-ray diffraction patterns using a three dimension crystallite size and microstrain model. This is available in Rietveld refinement software and consists in anisotropic broadening analysis of diffraction peaks. Crystallite size doesn't significantly change with the phase transformation contrary to microstrain that is multiplied, on average, by five. Furthermore, internal normal and shear microstress are multiplied, respectively, by 2 and 13 when {alpha}'-phase appears. Last, dislocation densities, calculated from crystallite size and microstrain, are compared to TEM results available in the literature.

  4. Analysis of neutron diffraction spectra acquired in situ during stress-induced transformations in superelastic NiTi

    International Nuclear Information System (INIS)

    Vaidyanathan, R.; Bourke, M.A.; Dunand, D.C.

    1999-01-01

    Neutron diffraction spectra were obtained during various stages of a reversible stress-induced austenite to martensite phase transformation in superelastic NiTi. This was accomplished by neutron diffraction measurements on bulk polycrystalline NiTi samples simultaneously subjected to mechanical loading. Analysis of the data was carried out using individual lattice plane (hkl) reflections as well as by Rietveld refinement. In the Rietveld procedure, strains in austenite were described in terms of an isotropic (hkl independent) and an anisotropic (hkl dependent) component. At higher stresses, austenite lattice plane reflections exhibited nonlinear and dissimilar elastic responses which may be attributed to the transformation. The texture evolution is significant in both austenite and martensite phases during the transformation and two approaches were used to describe this evolving texture, i.e., an ellipsoidal model due to March - Dollase and a generalized spherical-harmonic approach. The respective predictions of the phase fraction evolution as a function of applied stress were compared. A methodology is thus established to quantify the discrete phase strains, phase volume fractions, and texture during such transformations. copyright 1999 American Institute of Physics

  5. X-ray diffraction analysis of aluminium containing Al8Fe2Si processed by equal channel angular pressing

    International Nuclear Information System (INIS)

    Korchef, Atef; Champion, Yannick; Njah, Nabil

    2007-01-01

    A 99.1% aluminium with initial grain size of ∼85 μm was deformed by equal channel angular (ECA) pressing. The sample undergoes an effective strain of 1.07 N by N passes through the die. The material contains a low volume fraction of Al 8 Fe 2 Si precipitates located essentially at the grain boundaries. The analysis of the X-ray diffraction peaks showed a significant broadening, which was related to grain refinement and lattice distortions. The crystallite size, calculated using the Halder-Wagner method, reached 225 nm after two passes and did not subsequently change. A decrease of the lattice parameter was also observed after ECA pressing. This is due to a partial dissolution of the precipitates. The microstructure was stable up an annealing of 200 deg. C due to the precipitates which delay the diffusion process. The annealing of the ECA pressed samples up to 400 deg. C leads to a decrease in the X-ray diffraction peaks broadening and an increase of the lattice parameter. This is due to grain growth

  6. Diffraction gauging

    International Nuclear Information System (INIS)

    Wilkens, P.H.

    1978-01-01

    This system of gauging is now being designed to fit on an Excello NC lathe to measure the form, accuracy, and size of external contoured surfaces as they approach the finish machined size. A template profile of the finished workpiece, but 0.003 in. bigger on radius, will be aligned with the workpiece using a reference diameter and face on the machining fixture to leave a gap between the profile of the template and workpiece. A helium--neon laser beam will be projected through this gap using a rotating retroreflector and a fixed laser. The resulting diffraction pattern produced by the laser beam passing through the template to workpiece gap will be reflected and focused on a fixed diode array via a second retroreflector which moves and remains in optical alignment with the first. These retroreflectors will be rotated about a center that will enable the laser beam, which is shaped in a long slit, to scan the template workpiece gap from the pole to the equator of the workpiece. The characteristic diffraction pattern will be detected by the fixed diode array, and the signal levels from this array will be processed in a mini-computer programmed to produce a best fit through the two minima of the diode signals. The separation of the two minima will yield the size of the workpiece to template gap and this information will be presented to the machine tool operator

  7. BOOK REVIEW: Analysis of Residual Stress by Diffraction Using Neutron and Synchrotron Radiation

    Science.gov (United States)

    Fitzpatrick, ed M. E.; Lodini, A.

    2003-09-01

    The presence of residual stresses within engineering components is often a key feature in determining their usable lifetimes and failure characteristics. Residual surface compression can, for example, restrict the propagation of surface cracks through the bulk. As a consequence, it is essential to characterize the magnitude and spatial distribution of residual stresses and, at least for non-destructive testing, this is most widely achieved using diffraction of neutron and high energy synchrotron radiations. This book aims to provide a detailed description of the methodology used to determine residual stresses. The major emphasis is placed on the neutron method, this being the more widely established approach at present. It contains 20 chapters contributed by 23 authors, divided into five major parts. The overall layout is very logical, with the first part giving a general introduction to the use of neutrons and x-rays for materials research and summarizing the methods used for their production. Part 2 considers the more specific aspects of extracting the residual stress distribution within a bulk sample and includes some valuable comments on a number of potential experimental problems, such as the determination of the stress-free lattice parameter and the effects of broadening of the Bragg peaks. The experimental facilities currently available or under development are described in part 3, with the remaining two parts devoted to general and specific applications of the residual stress measurement technique. As expected with such a large number of different authors, there is some variation in style and quality. However, the text is generally easy to follow and, more importantly, it is largely free of the problems of inconsistent notation and dupication of material that can afflict multi-authored texts. My only negative comment concerns the latter portion of the book devoted to specific applications of the technique, which is illustrative rather than comprehensive. In

  8. Rietveld analysis using powder diffraction data with anomalous scattering effect obtained by focused beam flat sample method

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, Masahiko, E-mail: masahiko@spring8.or.jp; Katsuya, Yoshio, E-mail: katsuya@spring8.or.jp; Sakata, Osami, E-mail: SAKATA.Osami@nims.go.jp [Synchrotron X-ray Station at SPring-8, National Institute for Materials Science 1-1-1 Kouto, Sayo, Hyogo 679-5198 (Japan)

    2016-07-27

    Focused-beam flat-sample method (FFM) is a new trial for synchrotron powder diffraction method, which is a combination of beam focusing optics, flat shape powder sample and area detectors. The method has advantages for X-ray diffraction experiments applying anomalous scattering effect (anomalous diffraction), because of 1. Absorption correction without approximation, 2. High intensity X-rays of focused incident beams and high signal noise ratio of diffracted X-rays 3. Rapid data collection with area detectors. We applied the FFM to anomalous diffraction experiments and collected synchrotron X-ray powder diffraction data of CoFe{sub 2}O{sub 4} (inverse spinel structure) using X-rays near Fe K absorption edge, which can distinguish Co and Fe by anomalous scattering effect. We conducted Rietveld analyses with the obtained powder diffraction data and successfully determined the distribution of Co and Fe ions in CoFe{sub 2}O{sub 4} crystal structure.

  9. Rietveld analysis using powder diffraction data with anomalous scattering effect obtained by focused beam flat sample method

    International Nuclear Information System (INIS)

    Tanaka, Masahiko; Katsuya, Yoshio; Sakata, Osami

    2016-01-01

    Focused-beam flat-sample method (FFM) is a new trial for synchrotron powder diffraction method, which is a combination of beam focusing optics, flat shape powder sample and area detectors. The method has advantages for X-ray diffraction experiments applying anomalous scattering effect (anomalous diffraction), because of 1. Absorption correction without approximation, 2. High intensity X-rays of focused incident beams and high signal noise ratio of diffracted X-rays 3. Rapid data collection with area detectors. We applied the FFM to anomalous diffraction experiments and collected synchrotron X-ray powder diffraction data of CoFe_2O_4 (inverse spinel structure) using X-rays near Fe K absorption edge, which can distinguish Co and Fe by anomalous scattering effect. We conducted Rietveld analyses with the obtained powder diffraction data and successfully determined the distribution of Co and Fe ions in CoFe_2O_4 crystal structure.

  10. The microstructure of mechanically alloyed Al-Mg determined by X-ray diffraction peak profile analysis

    Energy Technology Data Exchange (ETDEWEB)

    Gubicza, J.; Kassem, M.; Ribarik, G.; Ungar, T

    2004-05-15

    The effect of the nominal Mg content and the milling time on the microstructure and the hardness of mechanically alloyed Al-rich Al-Mg solid solutions is studied. The crystallite size distribution and the dislocation structure are characterized by X-ray diffraction (XRD) peak profile analysis and the hardness is obtained from depth-sensing indentation tests. Magnesium gradually goes into solid solution during ball milling and after 3 h an almost complete solid solution is attained. With increasing milling time, the Mg concentration in solid solution, the dislocation density and the hardness increase, whereas the crystallite size decreases. A similar tendency of these parameters is observed at a particular duration of ball milling with increasing nominal Mg content. After 3 h milling there are no changes in both the microstructure and the hardness.

  11. Homogeneity characterisation of (U,Gd)O2 sintered pellets by X-ray diffraction powder analysis applying Rietveld method

    International Nuclear Information System (INIS)

    Leyva, Ana G.; Vega, Daniel R.; Trimarco, Veronica G.; Marchi, Daniel E.

    1999-01-01

    The (U,Gd)O 2 sintered pellets are fabricated by different methods. The homogeneity characterisation of Gd content seems to be necessary as a production control to qualify the process and the final product. The micrographic technique is the most common method used to analyse the homogeneity of these samples, this method requires time and expertise to obtain good results. In this paper, we propose an analysis of the X-ray diffraction powder patterns through the Rietveld method, in which the differences between the experimental data and the calculated from a crystalline structure model proposed are evaluated. This result allows to determine the cell parameters, that can be correlated with the Gd concentration, and the existence of other phases with different Gd ratio. (author)

  12. High pressure single-crystal micro X-ray diffraction analysis with GSE_ADA/RSV software

    Science.gov (United States)

    Dera, Przemyslaw; Zhuravlev, Kirill; Prakapenka, Vitali; Rivers, Mark L.; Finkelstein, Gregory J.; Grubor-Urosevic, Ognjen; Tschauner, Oliver; Clark, Simon M.; Downs, Robert T.

    2013-08-01

    GSE_ADA/RSV is a free software package for custom analysis of single-crystal micro X-ray diffraction (SCμXRD) data, developed with particular emphasis on data from samples enclosed in diamond anvil cells and subject to high pressure conditions. The package has been in extensive use at the high pressure beamlines of Advanced Photon Source (APS), Argonne National Laboratory and Advanced Light Source (ALS), Lawrence Berkeley National Laboratory. The software is optimized for processing of wide-rotation images and includes a variety of peak intensity corrections and peak filtering features, which are custom-designed to make processing of high pressure SCμXRD easier and more reliable.

  13. Grazing incidence x-ray diffraction analysis of zeolite NaA membranes on porous alumina tubes.

    Science.gov (United States)

    Kyotani, Tomohiro

    2006-07-01

    Zeolite NaA-type membranes hydrothermally synthesized on porous alumina tubes, for dehydration process, were characterized by grazing incidence 2 theta scan X-ray diffraction analysis (GIXRD). The fine structure of the membrane was studied fractionally for surface layer and for materials embedded in the porous alumina tube. The thickness of the surface layer on the porous alumina tube in the membranes used in this study was approximately 2-3 microm as determined from transmission electron microscopy with focused ion beam thin-layer specimen preparation technique (FIB-TEM). To discuss the effects of the membrane surface morphology on the GIXRD measurements, CaA-type membrane prepared by ion exchange from the NaA-type membrane and surface-damaged NaA-type membrane prepared by water leaching were also studied. For the original NaA-type membrane, 2 theta scan GIXRD patterns could be clearly measured at X-ray incidence angles (alpha) ranging from 0.1 to 2.0 deg in increments of 0.1 deg. The surface layers of the 2 - 3 microm on the porous alumina tube correspond to the alpha values up to ca. 0.2 deg. For the CaA-type and the surface-damaged NaA-type membranes, however, diffraction patterns from the surface layer could not be successfully detected and the others were somewhat broad. For all the three samples, diffraction intensities of both zeolite and alumina increased with depth (X-ray incidence angle, alpha) in the porous alumina tube region. The depth profile analysis of the membranes based on the GIXRD first revealed that amount of zeolite crystal embedded in the porous alumina tube is much larger than that in the surface layer. Thus, the 2 theta scan GIXRD is a useful method to study zeolite crystal growth mechanism around (both inside and outside) the porous alumina support during hydrothermal synthesis and to study water permeation behavior in the dehydration process.

  14. X-ray, synchrotron, and neutron diffraction analysis of Roman cavalry parade helmet fragment

    Czech Academy of Sciences Publication Activity Database

    Smrcok, L.; Petrik, I.; Langer, V.; Filinchuk, Y.; Beran, Přemysl

    2010-01-01

    Roč. 45, č. 10 (2010), s. 1025-1031 ISSN 0232-1300 Institutional research plan: CEZ:AV0Z10480505 Keywords : archaeometry * Roman helmet * phase analysis Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 0.946, year: 2010

  15. X-ray diffraction line profile analysis for defect study in Zr–2⋅5% Nb ...

    Indian Academy of Sciences (India)

    Unknown

    The microstructure characterization by X-ray line profile analysis is possible for determination of ... breadth method also gives the coherent domain size, dislocation density and micro-strain present in .... currently used for pressure tubes, has replaced Zircaloy-2 ..... the data on σ0, σNb, m, α, G, and b available in the litera-.

  16. ray diffraction

    African Journals Online (AJOL)

    Mgina

    Chemistry Department, University of Dar es Salaam,. P.O. Box 35061 ... XRD analysis. XRD analysis identified kaolinite, illite and montmorillonite ..... Skoog DA and West DM 1980 Principles of. Instrumental Analysis 2nd Edn, Holt –. Saunders ...

  17. Semiquantitative analysis of corrosion products in iron channel by the X-ray diffraction technique

    International Nuclear Information System (INIS)

    Bueno, C.R.E.; Varela, J.A.

    1995-01-01

    The corrosion in the us very important in the slag line region, but in others regions over and above this line there is a corrosion process still important. We have made a detailed mapping of phases present in seven different regions in the iron channel in three distinct positions. After the phases identifications, it was made a deconvolution of the diffractograms using Gaussian functions. The analysis of the relative intensity of each phase gave an idea for a semi-quantitative analysis and we have proposed a mechanism of the refractory corrosion. It was observed that the calcium oxide migrates by diffusion to different regions originating low melting point products like pseudo-wolastonite, anorthite and guelenite. (author)

  18. Non-destructive micro-X-ray diffraction analysis of painted artefacts: Determination of detection limits for the chromium oxide-zinc oxide matrix

    International Nuclear Information System (INIS)

    Nel, P.; Lau, D.; Hay, D.; Wright, N.

    2006-01-01

    The development of micro-X-ray diffraction (micro-XRD) enables non-destructive, in situ analysis of crystalline pigments on artworks and archaeological objects. Pigments with X-ray diffraction patterns with large peak intensities may complicate the identification of other components with lower absorption coefficients, especially if present in low concentrations in the paint sample. Investigation of this issue involved: (1) micro-XRD examination and analysis of the amorphous and crystalline phases of fifteen pigment films and (2) micro-XRD examination and semi-quantitative analysis of various chromium oxide-zinc oxide mixtures, which established detection limits as low as 5 ± 2%

  19. Method for total automation of many-dimensionl diffraction spectra analysis

    International Nuclear Information System (INIS)

    Zlokazov, V.B.

    1985-01-01

    A method meant for automatic analysis of amplitude many-dimensional spectra is described. At the first stage peak search including the procedures of smoothing, identification of peak vertices and their sorting is realized. The method is used in the FIND 2 and DOMUS FORTRAN programs that can operate both on the ES-1040 and CDC-6500 type large computers and SM-3 and SM-4 type small computers

  20. Dynamics from diffraction

    International Nuclear Information System (INIS)

    Goodwin, Andrew L.; Tucker, Matthew G.; Cope, Elizabeth R.; Dove, Martin T.; Keen, David A.

    2006-01-01

    We explore the possibility that detailed dynamical information might be extracted from powder diffraction data. Our focus is a recently reported technique that employs statistical analysis of atomistic configurations to calculate dynamical properties from neutron total scattering data. We show that it is possible to access the phonon dispersion of low-frequency modes using such an approach, without constraining the results in terms of some pre-defined dynamical model. The high-frequency regions of the phonon spectrum are found to be less well preserved in the diffraction data

  1. Phase identification and internal stress analysis of steamside oxides on superheater tubes by means of X-ray diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Pantleon, Karen; Montgomery, Melanie [Technical Univ. of Denmark, Lyngby (Denmark). Inst. of Manufacturing Engineering and Management

    2005-05-01

    For superheater tubes, the adherence of the inner steamside oxide is especially important as spallation of this oxide results in a) blockage of loops which cause insufficient steam flow through the superheaters and subsequently overheating and tube failure and b) spalled oxide can cause erosion of turbine blades. Oxide spallation is a serious problem for austenitic steels where the significant differences of the thermal expansion coefficients of steel and oxide cause relatively high thermal stresses. Usually, various oxides layered within the scale are suggested from microscopical observations of the morphology and/or topography of the oxide scale accompanied by the analysis of chemical elements present. Reports about the application of X-ray diffraction on the study of steamside oxide formation are very scarce in literature. If applied at all, XRD-studies are restricted to ideally flat samples oxidized under laboratory conditions, but relation to real operating conditions and the effect of the real sample geometry is missing. Within the frame of the project, steamside oxides on plant exposed components of ferritic/ martensitic X20CrMoV12-1 as well as fine- and coarse-grained austenitic TP347H were studied by means of X-ray diffraction. Depth dependent phase analysis on sample segments cut from the tubes was carried out by means of grazing incidence diffraction and, in order to obtain information from a larger depth, conventional XRD was combination with stepwise mechanical removal of the steamside oxides. After each removal step phase analysis was performed both on the segments and on the removed powders. Phase specific stress analysis was carried out on rings cut from the tube. Results show that steamside oxides on X20CrMoV12-1 consist of pure Hematite at the surface followed by a relatively thick layer of pure Magnetite. Both phases are under relatively high tensile stresses. While the phase composition of the Hematite layer appears to be the same for all

  2. Conformational analysis of phloroglucinols from hypericum Brasiliense by using x-ray diffraction and molecular modeling

    Energy Technology Data Exchange (ETDEWEB)

    Leal, Katia Z.; Lindgren, Eric B.; Correa, Arthur L., E-mail: kzleal@uol.com.b [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil). Inst. de Quimica. Dept. de Fisico-Quimica; Yoneda, Julliane D. [Universidade Federal Fluminense (UFF), Volta Redonda, RJ (Brazil). Polo Universitario de Volta Redonda; Pinheiro, Carlos B. [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Dept. de Fisica; Franca, Hildegardo S. [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil). Faculdade de Farmacia. Dept. de Tecnologia Farmaceutica

    2010-07-01

    In this work we intend to verify the applicability of a computational methodology to predict structural features of organic compounds with biological activity. We selected three phloroglucinols and compared their calculated conformational data with their X-ray crystallographic structure. The results showed that conformations obtained by conformational analysis with the AM1 method followed by geometry optimization by using the DFT B3LYP/6-31 G(d,p) basis set are in very good agreement with X-ray data, indicating that the methodology employed here seems to be a very useful tool in order to predict the conformational preference for this class of compounds. (author)

  3. Diffraction. Single crystal, magnetic

    International Nuclear Information System (INIS)

    Heger, G.

    1999-01-01

    The analysis of crystal structure and magnetic ordering is usually based on diffraction phenomena caused by the interaction of matter with X-rays, neutrons, or electrons. Complementary information is achieved due to the different character of X-rays, neutrons and electrons, and hence their different interactions with matter and further practical aspects. X-ray diffraction using conventional laboratory equipment and/or synchrotron installations is the most important method for structure analyses. The purpose of this paper is to discuss special cases, for which, in addition to this indispensable part, neutrons are required to solve structural problems. Even though the huge intensity of modern synchrotron sources allows in principle the study of magnetic X-ray scattering the investigation of magnetic structures is still one of the most important applications of neutron diffraction. (K.A.)

  4. Expression, purification, crystallization and preliminary X-ray diffraction analysis of the aspartate transcarbamoylase domain of human CAD

    International Nuclear Information System (INIS)

    Ruiz-Ramos, Alba; Lallous, Nada; Grande-García, Araceli; Ramón-Maiques, Santiago

    2013-01-01

    The recombinant aspartate transcarbamoylase domain of human CAD was expressed in E. coli, purified and crystallized in the presence and absence of the inhibitor PALA. X-ray diffraction data sets were collected for both crystal forms at 2.1 Å resolution. Aspartate transcarbamoylase (ATCase) catalyzes the synthesis of N-carbamoyl-l-aspartate from carbamoyl phosphate and aspartate in the second step of the de novo biosynthesis of pyrimidines. In prokaryotes, the first three activities of the pathway, namely carbamoyl phosphate synthetase (CPSase), ATCase and dihydroorotase (DHOase), are encoded as distinct proteins that function independently or in noncovalent association. In animals, CPSase, ATCase and DHOase are part of a 243 kDa multifunctional polypeptide named CAD. Up-regulation of CAD is essential for normal and tumour cell proliferation. Although the structures of numerous prokaryotic ATCases have been determined, there is no structural information about any eukaryotic ATCase. In fact, the only detailed structural information about CAD is that it self-assembles into hexamers and trimers through interactions of the ATCase domains. Here, the expression, purification and crystallization of the ATCase domain of human CAD is reported. The recombinant protein, which was expressed in bacteria and purified with good yield, formed homotrimers in solution. Crystallization experiments both in the absence and in the presence of the inhibitor PALA yielded small crystals that diffracted X-rays to 2.1 Å resolution using synchrotron radiation. The crystals appeared to belong to the hexagonal space group P6 3 22, and Matthews coefficient calculation indicated the presence of one ATCase subunit per asymmetric unit, with a solvent content of 48%. However, analysis of the intensity statistics suggests a special case of the P2 1 lattice with pseudo-symmetry and possibly twinning

  5. Operando X-ray diffraction analysis for a glyme-based Li-O_2 battery

    International Nuclear Information System (INIS)

    Yogi, C.; Takao, N.; Kubobuchi, K.; Matsumoto, M.; Mogi, M.; Imai, H.; Watanabe, T.

    2016-01-01

    We investigated the effect of the carbon species in the air (oxygen) electrode, electrolyte concentration, and humidity in the supplied O_2 gas on the Li-O_2 reactions by using the operando XRD analysis. Regarding carbon species, we found that the over-potentials in the galvanostatic discharge-charge process were suppressed when using the KB carbon in the air electrode. The results of operando XRD measurements revealed that the Li_2O_2 formed on the KB had the smaller crystalline or more amorphous like structures, which could be one reason for faster reaction kinetics of Li_2O_2 dissolution. The discharge-charge curves of the cells with different concentration of LiTFSI/(G4)_n electrolyte showed the slight difference but less differences in the Li_2O_2 formation and dissolution behaviors. In addition to the nature of Li_2O_2 products, reaction of Li-salts would also have ineligible effects. We also found that the higher humidity in oxygen produced more the LiOH and promoted the Li_2O_2 dissolution, which indicate that the LiOH formation could affect the Li_2O_2 morphologies or surface chemistries. Our present results demonstrated that the operando XRD measurement are useful for analyzing the reaction mechanism of Li-O_2 battery.

  6. Analysis of magnetic correlations in layered or multiferroic transition element oxides using neutron diffraction

    International Nuclear Information System (INIS)

    Finger, Thomas

    2013-01-01

    Due to a great variety of physical phenomena the material class of transition metal oxides offers a large field of work for researchers, the more so as many underlying mechanisms are not understood yet. Of these materials a set of systems closely related to the manganates is investigated in this thesis via neutron scattering, emphasizing the analysis of magnetic correlations. It is shown, that for doping concentrations 0 ≤ x ≤ 0.5 the Co 2+ -ions in the layered cobaltates always exhibit a high-spin state with S = (3)/(2), whereas existing Co 3+ -ions adopt a low-spin state with S = 0 and stay non-magnetic. Furthermore, the magnetic correlations of three chiral multiferroics are investigated: Firstly, in MnWO 4 a memory effect is described; the crystal remembers its preceding chiral state even in the paramagnetic phase. In TbMnO 3 chiral fluctuations slightly above the multiferroic transition are investigated; it is possible to switch them by an applied external E-field. Finally, in DyMnO 3 the magnetic excitations are examined for the first time; they are comparable to those in TbMnO 3 .

  7. Grain size analysis of sediments from the northern Andaman Sea: Comparison of laser diffraction and sieve-pipette techniques

    Digital Repository Service at National Institute of Oceanography (India)

    Ramaswamy, V.; Rao, P.S.

    measured with laser diffraction show that 99% of the particles have an upper size range between 4.8 and 7.7 mu m. A calibration relationship between pipette and laser diffraction techniques has been developed for the northern Andaman Sea. A clay particle...

  8. Non-Destructive Quantification of Plastic Deformation in Steel: Employing X-Ray Diffraction Peak Broadening Analysis

    Science.gov (United States)

    2013-09-01

    justifier l’élaboration d’une nouvelle analyse des pics de DRX dans les installations de RDDC Atlantique. Résultats : Plusieurs auteurs se sont penchés...2 3 X-Ray Diffraction Theory ...3 X-Ray Diffraction Theory The manifestation of desirable physical and chemical material properties may be readily discerned through investigation

  9. Determination of the absolute configuration of (+)-neopentyl-1-d alcohol by neutron and x-ray diffraction analysis.

    Science.gov (United States)

    Yuan, H S; Stevens, R C; Bau, R; Mosher, H S; Koetzle, T F

    1994-12-20

    The absolute configuration of (+)-neopentyl-1-d alcohol, prepared by the reduction of 2,2-dimethylpropanal-1-d by actively fermenting yeast, has been determined to be S by neutron diffraction. The neutron study was carried out on the phthalate half ester of neopentyl-1-d alcohol, crystallized as its strychnine salt. The absolute configuration of the (-)-strychninium cation was first determined by an x-ray anomalous dispersion study of its iodide salt. The chiral skeleton of strychnine then served as a reference from which the absolute configuration of the -O-CHD-C(CH3)3 group of neopentyl phthalate was determined. Difference Fourier maps calculated from the neutron data showed unambiguously that the -O-CHD-C(CH3)3 groups of both independent molecules in the unit cell had the S configuration. This work proves conclusively that the yeast system reduces aldehydes by delivering hydrogen to the re face of the carbonyl group. Crystallographic details: (-)-strychninium (+)-neopentyl-1-d phthalate, space group P2(1) (monoclinic), a = 18.564(6) A, b = 7.713(2) A, c = 23.361(8) A, beta = 94.18(4) degrees, V = 3336.0(5) A3, Z = 2 (T = 100 K). Final agreement factors are R(F) = 0.073 for 2768 reflections collected at room temperature (x-ray analysis) and R(F) = 0.144 for 960 reflections collected at 100 K (neutron analysis).

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

    International Nuclear Information System (INIS)

    Darin, Gaspar; Imakuma, Kengo; Martinez, Luis G.; Turrrilas, Xabier M.; Ichikawa, Rodrigo U.; Silva, André S.B.; Durazzo, Michelangelo; Riella, Humberto G.; Urano, Elita

    2017-01-01

    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 2 O 3 . Recently, the phase diagram and melting point has been investigated for high contents of Gd 2 O 3 in the U-Gd-O system, that means a solid solution of the composition (U 1-x , Gd x )O 2 for 0analysis of the U-Gd-O system for high contents of Gd 2 O 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 2 O 3 in the system. Finally, mean crystallite sizes were determined and correlated with the weight fraction of the phases. (author)

  11. 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 0analysis 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)

  12. Synthetic hydroxyapatites doped with Zn(II) studied by X-ray diffraction, infrared, Raman and thermal analysis

    Science.gov (United States)

    Guerra-López, José R.; Echeverría, Gustavo A.; Güida, Jorge A.; Viña, Raúl; Punte, Graciela

    2015-06-01

    Calcium hydroxyapatite (CaHap) formation when different amounts of Zn(II) are present in the mother solution has been investigated by atomic absorption, infrared and Raman spectroscopies, X-ray diffraction and thermal analysis (DTA and TG). The studied samples have been synthesized at T=95 °C and pH 9 in air. The analysis of the results have shown that the pure CaHap sample crystallizes in the monoclinic form P21/b. Concentrations up to 20% of Zn(II) in the mother solution, equivalent to smaller concentrations in solid (up to 9.1% in wt), favor the formation of the hexagonal apatite, P63/m, while Zn(II) concentrations higher than 20% in solution help an amorphous phase development where vibrational spectra indicated coexistence of two phases: an apatite and ZnNH4PO4·H2O. Infrared data of thermal treated samples endorse that HPO42- ion had not been incorporated in Zn(II) doped samples during the synthesis process. Present results also allow to conclude that Zn(II) cation exhibits a preference to occupy the Ca2 site of the apatite structure and induces water adsorption and a small quantity of CO32- cation incorporation, leading to formation of a less crystalline Ca deficient apatite.

  13. 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...

  14. Fluorescent and X-ray diffraction analysis for industrial wastes of the Comandante Pedro Soto Alba plant

    International Nuclear Information System (INIS)

    Herrera, V.

    1980-05-01

    It is presented a qualitative X-ray elemental fluorescence and diffraction analysis of the low-nickel portion (deands) of Cuban lateritic ores from Moa and Nicaro, the tailings of the Cuba nickel plant Comandante Pedro Soto Alba (in Moa) and its magnetic concentrated fractions (results of enrichment test in magnetizing roasting and wet magnetic separation). In all samples as main phase hematite (α-Fe 2 O 3 ) is observed. In all deands samples there were also high concentrations of goethite (α-FeOOH) and aluminium hydroxide (Al(OH) 3 ). In the Nicaro deands, in addition to name above phases, a modification of delta-iron hydroxide, with Ni and/or Co substitutions in the forms delta-(Fesub(0,67)Nisub(0,33))OOH, delta-(Fesub(0,67)Cosub(0,33))OOH or delta-(Fesub(0,67)Nisub(x)Cosub(0,33-x))OOH seems possible. In Moa tailings besides the hematite, the more abundant phases are a basic hydrated aluminium sulphate and gypsum. The magnetic enriched fractions are practically by a spinel of the maghemite type, and chromium seems to be included into the spinel lattice. (author)

  15. High resolution electron back-scatter diffraction analysis of thermally and mechanically induced strains near carbide inclusions in a superalloy

    Energy Technology Data Exchange (ETDEWEB)

    Karamched, Phani S., E-mail: phani.karamched@materials.ox.ac.uk [Department of Materials, University of Oxford, Parks Road, Oxford OX1 3PH (United Kingdom); Wilkinson, Angus J. [Department of Materials, University of Oxford, Parks Road, Oxford OX1 3PH (United Kingdom)

    2011-01-15

    Cross-correlation-based analysis of electron back-scatter diffraction (EBSD) patterns has been used to obtain high angular resolution maps of lattice rotations and elastic strains near carbides in a directionally solidified superalloy MAR-M-002. Lattice curvatures were determined from the EBSD measurements and used to estimate the distribution of geometrically necessary dislocations (GNDs) induced by the deformation. Significant strains were induced by thermal treatment due to the lower thermal expansion coefficient of the carbide inclusions compared to that of the matrix. In addition to elastic strains the mismatch was sufficient to have induced localized plastic deformation in the matrix leading to a GND density of 3 x 10{sup 13} m{sup -2} in regions around the carbide. Three-point bending was then used to impose strain levels within the range {+-}12% across the height of the bend bar. EBSD lattice curvature measurements were then made at both carbide-containing and carbide-free regions at different heights across the bar. The average GND density increases with the magnitude of the imposed strain (both in tension and compression), and is markedly higher near the carbides particles. The higher GND densities near the carbides (order of 10{sup 14} m{sup -2}) are generated by the large strain gradients produced around the plastically rigid inclusion during mechanical deformation with some minor contribution from the pre-existing residual deformation caused by the thermal mismatch between carbide and nickel matrix.

  16. Cloning, expression, purification, crystallization and preliminary X-ray diffraction analysis of chlorite dismutase: a detoxifying enzyme producing molecular oxygen

    Energy Technology Data Exchange (ETDEWEB)

    Geus, Daniël C. de, E-mail: d.de.geus@chem.leidenuniv.nl; Thomassen, Ellen A. J.; Feltz, Clarisse L. van der; Abrahams, Jan Pieter [Biophysical Structural Chemistry, Leiden University, Einsteinweg 55, 2333 CC Leiden (Netherlands)

    2008-08-01

    Preliminary X-ray data collection and analysis for crystals of chlorite dismutase, a haem-based enzyme that very effectively reduces chlorite to chloride while producing molecular oxygen, is reported to 2.1 Å resolution. Chlorite dismutase, a homotetrameric haem-based protein, is one of the key enzymes of (per)chlorate-reducing bacteria. It is highly active (< 2 kU mg{sup −1}) in reducing the toxic compound chlorite to the innocuous chloride anion and molecular oxygen. Chlorite itself is produced as the intermediate product of (per)chlorate reduction. The chlorite dismutase gene in Azospira oryzae strain GR-1 employing degenerate primers has been identified and the active enzyme was subsequently overexpressed in Escherichia coli. Chlorite dismutase was purified, proven to be active and crystallized using sitting drops with PEG 2000 MME, KSCN and ammonium sulfate as precipitants. The crystals belonged to space group P2{sub 1}2{sub 1}2 and were most likely to contain six subunits in the asymmetric unit. The refined unit-cell parameters were a = 164.46, b = 169.34, c = 60.79 Å. The crystals diffracted X-rays to 2.1 Å resolution on a synchrotron-radiation source and a three-wavelength MAD data set has been collected. Determination of the chlorite dismutase structure will provide insights into the active site of the enzyme, for which no structures are currently available.

  17. Rietveld profile analysis of calcined AlPO/sub 4/-11 using pulsed neutron powder diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Richardson, J.W. Jr.; Pluth, J.J.; Smith, J.V.

    1988-08-01

    Aluminium phosphate, AlPO/sub 4/, M/sub r/=121.95, orthorhombic, Icmm (disordered Al, P), Icm2 (ordered Al, P), a=13.5333(8), b=18.4845(10), c=8.3703(4) A, V=2094 A/sup 3/, Z=20, D/sub x/=1.93 g cm/sup -3/, T approx. = 295 K, R/sub wp/=0.031, R/sub F//sup 2/=0.109 (Icmm) and R/sub wp/=0.027, R/sub F//sup 2/=0.058 (Icm2) for 1017 independent reflections. Sample calcined at 873 K and dehydrated at 573 K. Time-of-flight neutron powder diffraction data were taken on the GPPD diffractometer at the Argonne National Laboratory Intense Pulsed Neutron Source. The structure was refined by Rietveld profile analysis in the range d=0.86-3.91 A in two space groups: Icmm assuming no ordering of Al and P, and Icm2 assuming strict alternation of Al and P on tetrahedral nodes. (orig./BHo).

  18. Burgers Vector Analysis of Vertical Dislocations in Ge Crystals by Large-Angle Convergent Beam Electron Diffraction.

    Science.gov (United States)

    Groiss, Heiko; Glaser, Martin; Marzegalli, Anna; Isa, Fabio; Isella, Giovanni; Miglio, Leo; Schäffler, Friedrich

    2015-06-01

    By transmission electron microscopy with extended Burgers vector analyses, we demonstrate the edge and screw character of vertical dislocations (VDs) in novel SiGe heterostructures. The investigated pillar-shaped Ge epilayers on prepatterned Si(001) substrates are an attempt to avoid the high defect densities of lattice mismatched heteroepitaxy. The Ge pillars are almost completely strain-relaxed and essentially defect-free, except for the rather unexpected VDs. We investigated both pillar-shaped and unstructured Ge epilayers grown either by molecular beam epitaxy or by chemical vapor deposition to derive a general picture of the underlying dislocation mechanisms. For the Burgers vector analysis we used a combination of dark field imaging and large-angle convergent beam electron diffraction (LACBED). With LACBED simulations we identify ideally suited zeroth and second order Laue zone Bragg lines for an unambiguous determination of the three-dimensional Burgers vectors. By analyzing dislocation reactions we confirm the origin of the observed types of VDs, which can be efficiently distinguished by LACBED. The screw type VDs are formed by a reaction of perfect 60° dislocations, whereas the edge types are sessile dislocations that can be formed by cross-slips and climbing processes. The understanding of these origins allows us to suggest strategies to avoid VDs.

  19. Effect of powder sample granularity on fluorescent intensity and on thermal parameters in x-ray diffraction Rietveld analysis

    International Nuclear Information System (INIS)

    Sparks, C.J.; Specht, E.D.; Ice, G.E.; Kumar, R.; Zschack, P.; Shiraishi, T.; Hisatsune, K.

    1991-01-01

    The effect of sample granularity on diffracted x-ray intensity was evaluated by measuring the 2θ dependence of x-ray fluorescence from various samples. Measurements were made in the symmetric geometry on samples ranging from single crystals to highly absorbing coarse powders. A characteristic shape for the absorption correction was observed. A demonstration of the sensitivity of Rietveld refined site occupation parameters is made on CuAu and Cu 50 Au 44 Ni 6 alloys refined with and without granularity corrections. These alloys provide a good example of the effect of granularity due to their large linear x-ray absorption coefficients. Sample granularity and refined thermal parameters obtained from the Rietveld analysis were found to be correlated. Without a granularity correction, the refined thermal parameters are too low and can actually become negative in an attempt to compensate for granularity. A general shape for granularity correction can be included in refinement procedures. If no granularity correction is included, data should be restricted to above 30 degrees 2θ, and thermal parameters should be ignored unless extreme precautions are taken to produce >5 μm particles and high packing densities

  20. Expression, purification, crystallization and preliminary X-ray diffraction analysis of rhesus macaque CD8αα homodimer

    International Nuclear Information System (INIS)

    Zong, Lili; Chen, Yong; Yan, Jinghua; Zhang, Jianhua

    2010-01-01

    CD8α exodomain protein, a crucial immune-system factor in rhesus macaque (M. mulatta), one of the best animal models for vaccine design, was assembled and crystallized. The full structure data will contribute to future studies of immune responses in rhesus macaques. As a T-cell co-receptor, CD8 binds to MHC class I molecules and plays a pivotal role in the activation of cytotoxic T lymphocytes. To date, structures of CD8 have been solved for two different mammals: human and mouse. The infection of rhesus macaques (Macaca mulatta) by simian immunodeficiency virus (SIV) is the best animal model for studying HIV. In this study, the rhesus macaque CD8 (rCD8) αα homodimer was obtained and rCD8α exodomain protein crystals were successfully obtained for further structural analysis. Diffraction data were collected to a resolution of 2.4 Å. The crystal belonged to space group P2 1 2 1 2 1 , with unit-cell parameters a = 46.52, b = 56.28, c = 82.40 Å. These data will facilitate further studies on the structural differences between these CD8 structures and the cellular immune responses of rhesus macaque

  1. X-ray diffraction phase analysis of crystalline copper corrosion products after treatment in different chloride solutions

    International Nuclear Information System (INIS)

    Chmielova, M.; Seidlerova, J.; Weiss, Z.

    2003-01-01

    The corrosion products Cu 2 (OH) 3 Cl, Cu 2 O, and CuCl 2 were identified on the surface of copper plates after their four days treating in three different sodium chloride, sodium/magnesium, and sodium/calcium chloride solutions using X-ray diffraction powder analysis. However, the quantitative proportions of individual corrosion products differ and depend on the type of chloride solution used. Treating of copper plates only in the sodium chloride solution produced the mixture of corrosion products where Cu 2 O is prevailing over the Cu 2 (OH) 3 Cl and CuCl 2 was not identified. The sample developed after treating of the cooper surface in the sodium/magnesium chloride solution contains Cu 2 (OH) 3 Cl and CuCl 2 prevailing over the Cu 2 O, while the sample developed after treatment of copper in sodium/calcium chloride solution contains Cu 2 (OH) 3 Cl prevailing over CuCl 2 and Cu 2 O was not identified

  2. Purification, crystallization and preliminary X-ray diffraction analysis of the human mismatch repair protein MutSβ

    International Nuclear Information System (INIS)

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

    2011-01-01

    Human MutSβ is a 232 kDa heterodimer (MSH2–MSH3) involved in the lesion-recognition step of mismatch repair. Here, the overexpression, purification, biochemical characterization and cocrystallization of MutSβ with a duplex DNA substrate are reported. MutSβ is a eukaryotic mismatch repair protein that preferentially targets extrahelical unpaired nucleotides and shares partial functional redundancy with MutSα (MSH2–MSH6). Although mismatch recognition by MutSα has been shown to involve a conserved Phe-X-Glu motif, little is known about the lesion-binding mechanism of MutSβ. Combined MSH3/MSH6 deficiency triggers a strong predisposition to cancer in mice and defects in msh2 and msh6 account for roughly half of hereditary nonpolyposis colorectal cancer mutations. These three MutS homologs are also believed to play a role in trinucleotide repeat instability, which is a hallmark of many neurodegenerative disorders. The baculovirus overexpression and purification of recombinant human MutSβ and three truncation mutants are presented here. Binding assays with heteroduplex DNA were carried out for biochemical characterization. Crystallization and preliminary X-ray diffraction analysis of the protein bound to a heteroduplex DNA substrate are also reported

  3. Contribution to the X-ray diffraction analysis method of the micro-structural and mechanical state of heterogenous materials

    International Nuclear Information System (INIS)

    Ji, V.

    2003-09-01

    The analysis of internal stresses through X-ray diffraction (DRX) has been used to study the micro-structure of various heterogenous materials: two-phase materials, composite materials, coated materials and alloys such as Ti-Al, Inconel-600 and 20CDV5-08 steel. In the case of the Ti-Al alloy we have achieved for the first time the experimental assessment of the compliance constant, of the level of internal stresses, and of the behaviour law of each phase as a function of the changes in duplex micro-structures. Local, direct and accurate information given by DRX have been used to feed micro-mechanical simulations and the results of the simulation are consistent with macroscopic mechanical testing. Accurate DRX analyses on CMC (ceramic matrix composite) have allowed us to confirm the thermal origin of internal stresses. As for thick copper layers made through thermal projection, DRX method combined to in-situ tensile testing has permitted us to measure the elasticity modulus and the distribution of macroscopic stresses inside the coating and the substrate. We have also determined the elastic limit of a TiN layer on a steel substrate. (A.C.)

  4. Study by X-ray diffraction and mechanical analysis of the residual stress generation during thermal spraying

    International Nuclear Information System (INIS)

    Pina, J.; Dias, A.; Lebrun, J.L.

    2003-01-01

    Thermally sprayed coatings are formed by the deposition of molten or partially molten particles, propelled onto a substrate where they impact, spread and solidify rapidly. Residual stresses are expected within the sprayed deposit as a consequence of the release of thermal and kinetic energies. A wide range of materials and two spraying techniques are considered in this study, namely atmospheric plasma spraying (APS) and high-velocity oxygen fuel. Stresses were determined by the X-ray diffraction (XRD) method. The results were compared with those calculated by mechanical analysis of stress relief in coatings detached from the substrate. Comparison of the results for adherent and free-standing coatings shows that the residual stress state can be resolved in terms of the components suggested by models that propose two stages of stress generation: quenching stresses and secondary-cooling stresses. The in-depth distribution of residual stresses, through the coating thickness, is discussed in terms of the nature of the coating system

  5. Operation manual for EDXRDDA - a software package for Bragg peak analysis of energy dispersive powder X-ray diffraction data

    International Nuclear Information System (INIS)

    Jayaswal, Balhans; Vijaykumar, V.; Momin, S.N.; Sikka, S.K.

    1992-01-01

    EDXRDDA is a software package for analysis of raw data for energy dispersive x-ray diffraction from powder samples. It resolves the spectra into individual peaks by a constrained non-linear least squares method (Hughes and Sexton, 1988). The profile function adopted is the Gaussian/Lorentzian product with the mixing ratio refinable in the program. The program is implemented on an IBM PC and is highly interactive with extensive plotting facilities. This report is a user's guide for running the program. In the first step after inputting the spectra, the full spectra is plotted on the screen. The user then chooses a portion of this for peak resolution. The initial guess for the peak intensity, peak position are input with the help of a cursor or a mouse. Upto twenty peaks can be fitted at a time in an interval of 500 channels. For overlapping peaks, various constraints can be applied. Bragg peaks and fluorescence peaks with different half widths can be handled simultaneously. The program on execution produces a look up table which contains the refined values of the peak position, half width, peak intensity, integrated intensity, and their error estimates of each peak. The program is very general and can also be used for curve fitting of data from many other experiments. (author). 2 refs., 7 figs., 2 appendices

  6. X-Ray diffraction analysis of thermally evaporated copper tin selenide thin films at different annealing temperature

    International Nuclear Information System (INIS)

    Mohd Amirul Syafiq Mohd Yunos; Zainal Abidin Talib; Wan Mahmood Mat Yunus; Josephine Liew Ying Chyi; Wilfred Sylvester Paulus

    2010-01-01

    Semiconductor thin films Copper Tin Selenide, Cu 2 SnSe 3 , a potential compound for semiconductor radiation detector or solar cell applications were prepared by thermal evaporation method onto well-cleaned glass substrates. The as-deposited films were annealed in flowing purified nitrogen, N 2 , for 2 hours in the temperature range from 100 to 500 degree Celsius. The structure of as-deposited and annealed films has been studied by X-ray diffraction technique. The semi-quantitative analysis indicated from the Reitveld refinement show that the samples composed of Cu 2 SnSe 3 and SnSe. These studies revealed that the films were structured in mixed phase between cubic space group F-43 m (no. 216) and orthorhombic space group P n m a (no. 62). The crystallite size and lattice strain were determined from Scherrer calculation method. The results show that increasing in annealing temperature resulted in direct increase in crystallite size and decrease in lattice strain. (author)

  7. Conformational analysis of an acyclic tetrapeptide: ab-initio structure determination from X-ray powder diffraction, Hirshfeld surface analysis and electronic structure.

    Science.gov (United States)

    Das, Uday; Naskar, Jishu; Mukherjee, Alok Kumar

    2015-12-01

    A terminally protected acyclic tetrapeptide has been synthesized, and the crystal structure of its hydrated form, Boc-Tyr-Aib-Tyr-Ile-OMe·2H2O (1), has been determined directly from powder X-ray diffraction data. The backbone conformation of tetrapeptide (1) exhibiting two consecutive β-turns is stabilized by two 4 → 1 intramolecular N-H · · · O hydrogen bonds. In the crystalline state, the tetrapeptide molecules are assembled through water-mediated O-H · · · O hydrogen bonds to form two-dimensional molecular sheets, which are further linked by intermolecular C-H · · · O hydrogen bonds into a three-dimensional supramolecular framework. The molecular electrostatic potential (MEP) surface of (1) has been used to supplement the crystallographic observations. The nature of intermolecular interactions in (1) has been analyzed quantitatively through the Hirshfeld surface and two-dimensional fingerprint plot. The DFT optimized molecular geometry of (1) agrees closely with that obtained from the X-ray structure analysis. The present structure analysis of Boc-Tyr-Aib-Tyr-Ile-OMe·2H2 O (1) represents a case where ab-initio crystal structure of an acyclic tetrapeptide with considerable molecular flexibility has been accomplished from laboratory X-ray powder diffraction data. Copyright © 2015 European Peptide Society and John Wiley & Sons, Ltd.

  8. Thermal analysis, X-ray powder diffraction and electron microscopy data related with the production of 1:1 Caffeine:Glutaric Acid cocrystals

    Directory of Open Access Journals (Sweden)

    Íris Duarte

    2016-09-01

    Full Text Available The data presented in this article are related to the production of 1:1 Caffeine:Glutaric Acid cocrystals as part of the research article entitled “Green production of cocrystals using a new solvent-free approach by spray congealing” (Duarte et al., 2016 [1]. More specifically, here we present the thermal analysis and the X-ray powder diffraction data for pure Glutaric Acid, used as a raw material in [1]. We also include the X-ray powder diffraction and electron microscopy data obtained for the 1:1 Caffeine:Glutaric Acid cocrystal (form II produced using the cooling crystallization method reported in “Operating Regions in Cooling Cocrystallization of Caffeine and Glutaric Acid in Acetonitrile” (Yu et al., 2010 [2]. Lastly, we show the X-ray powder diffraction data obtained for assessing the purity of the 1:1 Caffeine:Glutaric cocrystals produced in [1].

  9. Crystallization and preliminary X-ray diffraction analysis of the sialic acid-binding domain (VP8*) of porcine rotavirus strain CRW-8

    International Nuclear Information System (INIS)

    Scott, Stacy A.; Holloway, Gavan; Coulson, Barbara S.; Szyczew, Alex J.; Kiefel, Milton J.; Itzstein, Mark von; Blanchard, Helen

    2005-01-01

    The sialic acid-binding domain (VP8*) component of the porcine CRW-8 rotavirus spike protein has been overexpressed in E. coli, purified and co-crystallized with an N-acetylneuraminic acid derivative. X-ray diffraction data have been collected to 2.3 Å, which has enabled determination of the structure by molecular replacement. Rotavirus recognition and attachment to host cells involves interaction with the spike protein VP4 that projects outwards from the surface of the virus particle. An integral component of these spikes is the VP8* domain, which is implicated in the direct recognition and binding of sialic acid-containing cell-surface carbohydrates and facilitates subsequent invasion by the virus. The expression, purification, crystallization and preliminary X-ray diffraction analysis of VP8* from porcine CRW-8 rotavirus is reported. Diffraction data have been collected to 2.3 Å resolution, enabling the determination of the VP8* structure by molecular replacement

  10. Crystallization and preliminary X-ray diffraction analysis of the sialic acid-binding domain (VP8*) of porcine rotavirus strain CRW-8

    Energy Technology Data Exchange (ETDEWEB)

    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. [Department of Microbiology and Immunology, The University of Melbourne, Victoria 3010 (Australia); Szyczew, Alex J.; Kiefel, Milton J.; Itzstein, Mark von; 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)

    2005-06-01

    The sialic acid-binding domain (VP8*) component of the porcine CRW-8 rotavirus spike protein has been overexpressed in E. coli, purified and co-crystallized with an N-acetylneuraminic acid derivative. X-ray diffraction data have been collected to 2.3 Å, which has enabled determination of the structure by molecular replacement. Rotavirus recognition and attachment to host cells involves interaction with the spike protein VP4 that projects outwards from the surface of the virus particle. An integral component of these spikes is the VP8* domain, which is implicated in the direct recognition and binding of sialic acid-containing cell-surface carbohydrates and facilitates subsequent invasion by the virus. The expression, purification, crystallization and preliminary X-ray diffraction analysis of VP8* from porcine CRW-8 rotavirus is reported. Diffraction data have been collected to 2.3 Å resolution, enabling the determination of the VP8* structure by molecular replacement.

  11. Determination of the absolute configuration of (+)-neopentyl-1-d alcohol by neutron and x-ray diffraction analysis

    Energy Technology Data Exchange (ETDEWEB)

    Yuan, H.S.H.; Stevens, R.C.; Bau, R. (Univ. of Southern California, Los Angeles, CA (United States)); Mosher, H.S. (Stanford Univ., CA (United States)); Koetzle, T.F. (Brookhaven National Lab., Upton, NY (United States))

    1994-12-20

    The absolute configuration of (+)-neopentyl-1-d alcohol, prepared by the reduction of 2,2-dimethylpropanol-1-d by actively fermenting yeast, has been determined to be S by neutron diffraction. The neutron study was carried out on the phthalate half ester of neopentyl-1-d alcohol, crystallized as its strychnine salt. The absolute configuration of the (-)-strychninium cation was first determined by an x-ray anomalous dispersion study of its iodide salt. The chiral skeleton of strychnine then served as a reference from which the absolute configuration of the -O-CHD-C(CH[sub 3])[sub 3] group of neopentyl phthalate was determined. Difference Fourier maps calculated from the neutron data showed unambiguously that the -O-CHD-C(CH[sub 3])[sub 3] groups of both independent molecules in the unit cell had the S configuration. This work proves conclusively that the yeast system reduces aldehydes by delivering hydrogen to the re face of the carbonyl group. Crystallographic details: (-)-strychninium (+)-neopentyl-1-d phthalate, space group P2[sub 1] (monoclinic), a = 18.564(6) [angstrom], b = 7.713(2) [angstrom], c = 23.361(8) [angstrom], [beta] = 94.18(4)[degrees], V = 3336.0(5) [angstrom][sup 3], Z = 2 (T = 100 K). Final agreement factors are R(F) = 0.073 for 2768 reflections collected at room temperature (x-ray analysis) and R(F) = 0.144 for 960 reflections collected at 100 K (neutron analysis). 49 refs., 7 figs., 2 tabs.

  12. X-ray diffraction stress analysis of interrupted titanium nitride films: Combining the sin2ψ and crystallite group methods

    International Nuclear Information System (INIS)

    Sinkovits, Theo; Zhao, Yue; O'Brien, Rebecca; Dowey, Steve

    2014-01-01

    Interruptions during film growth have been discussed by researchers to assist in understanding the evolution of stress in physical vapour deposition films. A change in intrinsic stress is directly related to microstructure, hence careful analysis of stress in films can provide valuable structure–stress correlated information. In this study we discuss the use of combining two X-ray diffraction (XRD) stress analysis methods to elucidate the effect of interruptions during growth on the residual stress of TiN films. The sin 2 ψ and crystallite group method (CGM), scanning the (220) peaks from all grains in the film and only (111) oriented crystallites respectively, were used to analyse residual stress in standard and interrupted cathodic arc TiN films 1.5, 3.5 and 6.5 μm thick, grown on high-speed steel substrates. The sin 2 ψ method does not reveal any changes in stress with interruptions, however, measurements using the CGM show increased compressive stress and increased a 0 in the resultant TiN films. A comparison of results from both XRD methods indicates that an increased compressive stress from interruptions could be due to an increased number of defects in (111) oriented grains during the interruptions which would also affect a 0 as evident. In both methods, compressive stresses are found to decrease with increased thickness of films. - Highlights: • Interrupting TiN film growth increases compressive stress in (111) grains. • Increased stress is believed to be caused by defects incorporated into or not annealed out of (111) grains. • A comparison of sin 2 ψ and CGM results reveals differences in stress. • Compressive stress decreases as TiN films increase in thickness from 1.5 μm to 6.5 μm

  13. 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

  14. Grazing incidence diffraction : A review

    Energy Technology Data Exchange (ETDEWEB)

    Gilles, B [LTPCM, ENSEEG. St. Martin d` Heres. (France)

    1996-09-01

    Different Grazing Incidence Diffraction (GID) methods for the analysis of thin films and multilayer structures are reviewed in three sections: the reflectivity is developed in the first one, which includes the non-specular diffuse scattering. The second one is devoted to the extremely asymmetric Bragg diffraction and the third one to the in-plane Bragg diffraction. Analytical formulations of the scattered intensities are developed for each geometry, in the framework of the kinetical analysis as well as the dynamical theory. Experimental examples are given to illustrate the quantitative possibility of the GID techniques.

  15. Analysis of diffractive dissociation of K- into K-π+π- on a liquid hydrogen target at the compass spectrometer

    International Nuclear Information System (INIS)

    Jasinski, Prometeusz Kryspin

    2012-01-01

    The systematic exploration of excited meson and baryon states was the central topic of the COmmon Muon Proton Apparatus for Structure and Spectroscopy (COMPASS) physics program in the years 2008 and 2009 at the CERN facility. Particularly states non fitting a constituent quark model were searched for, identified by their exotic quantum numbers which are forbidden by a simple q anti q scheme. A high energetic hadron-beam on a fixed target yielded in resonances decaying into a large variety of final states. The diffractive and central production mechanisms allowed for a clean exclusive selection of channels such as π - p → π + π - π + p recoil , which then were analysed with a high precision and a huge number of events. Apart from the main pion component in the negative hadron beam a small fraction of kaons of about 2.5% allowed the study of light strange resonances in the K - π + π - decay channel. The best measurement in this channel was quoted to be so far the measurement of the WA03 experiment at CERN. The ACCMOR-collaboration has the data recorded and analysed with an experimental set-up very similar to the COMPASS-spectrometer. COMPASS had therefore not only the ability to remeasure this channel with a significantly higher number of events and better precision to cross-check those over 30 years old results. Moreover, improved analysis methods together with new evidences from other experiments, are expected to enlighten our present picture of the hadron spectrum. Chapter 1 introduces the concept of meson spectroscopy. The formation of bound quark anti-quark systems allows to interpret our measurements in terms of coupled quantum numbers, with properties as spin, charge conjugation and parity. Particularly kaonic isospin I=(1)/(2) resonances are classified as proposed by group theory and differences to I=1 and I=0 states, formed mainly by u and d quarks and their anti-quarks, are pointed out. That chapter introduces also the production mechanisms used to

  16. Analysis of X-band radar images for the detection of the reflected and diffracted waves in coastal zones

    Science.gov (United States)

    Ludeno, Giovanni; Natale, Antonio; Soldovieri, Francesco; Vicinanza, Diego; Serafino, Francesco

    2014-05-01

    The observation of nearshore waves and the knowledge of the sea state parameters can play a crucial role for the safety of harbors and ocean engineering. In the last two decades, different algorithms for the estimation of sea state parameters, surface currents and bathymetry from X-band radar data have been developed and validated [1, 2]. The retrieval of ocean wave parameters such as significant height, period, direction and wavelength of the dominant wave is based on the spectral analysis of data sequences collected by nautical X-band radars [3]. In particular, the reconstruction of the wave motion is carried out through the inversion procedure explained in [1-3], which exploits the dispersion relationship to define a band pass filter used to separate the energy associated with the ocean waves from the background noise. It is worth to note that the shape of such a band pass filter depends upon the value of both the surface currents and bathymetry; in our reconstruction algorithm these parameters are estimated through the (Normalized Scalar Product) procedure [1], which outperforms other existing methods (e.g., the Least Squares) [4]. From the reconstructed wave elevation sequences we can get the directional spectrum that provides useful information (i.e., wavelength, period, direction and amplitude) relevant to the main waves contributing to the wave motion. Of course, in coastal zones a number of diffraction and reflection phenomena can be observed, due to sea-waves impinging obstacles as jetties, breakwaters and boats. In the present paper we want to show the capability to detect reflected and diffracted sea-waves offered by the processing of X-band radar data. Further details relevant to the obtained results will be provided in the full paper and at the conference time. References [1] F. Serafino, C. Lugni, F. Soldovieri, "A novel strategy for the surface current determination from marine X-Band radar data", IEEE Geosci. and Remote Sensing Letters, vol. 7, no

  17. Development of Kossel micro-diffraction for strain and stress analysis at the micrometer scale: applications to crystalline materials

    International Nuclear Information System (INIS)

    Bouscaud, D.

    2012-01-01

    X-ray diffraction is a non-destructive method frequently used in materials science to analyse the stress state at a macroscopic scale. Due to the growing complexity of new materials and their applications, it is necessary to know the strain and stress state at a lower scale. Thus, a Kossel micro-diffraction experimental set-up was developed inside a scanning electron microscope. It allows to obtain the crystallographic orientation as well as the strains and stresses within a volume of a few cubic micrometers. Some experiments were also performed using a synchrotron radiation. An experimental procedure was developed to optimize the acquisition of Kossel line patterns and their post-processing. The stress calculation from Kossel patterns was validated by comparing the stress state of single crystals during in situ mechanical loading, obtained by Kossel micro-diffraction and with classical diffraction methods. Then Kossel micro-diffraction was applied to polycrystalline samples by gradually decreasing the grain size. Intergranular stress heterogeneities were for example measured in an interstitial-free steel. Experiments were finally carried out in thin layer samples representative of microelectronic components. (author)

  18. Electron diffraction from carbon nanotubes

    International Nuclear Information System (INIS)

    Qin, L-C

    2006-01-01

    . Finally, determination of the handedness of carbon nanotubes using electron diffraction is reviewed and discussed with both theoretical analysis and experimental examples

  19. Crystallization and preliminary X-ray diffraction analysis of the peripheral light-harvesting complex LH2 from Marichromatium purpuratum.

    Science.gov (United States)

    Cranston, Laura J; Roszak, Aleksander W; Cogdell, Richard J

    2014-06-01

    LH2 from the purple photosynthetic bacterium Marichromatium (formerly known as Chromatium) purpuratum is an integral membrane pigment-protein complex that is involved in harvesting light energy and transferring it to the LH1-RC `core' complex. The purified LH2 complex was crystallized using the sitting-drop vapour-diffusion method at 294 K. The crystals diffracted to a resolution of 6 Å using synchrotron radiation and belonged to the tetragonal space group I4, with unit-cell parameters a=b=109.36, c=80.45 Å. The data appeared to be twinned, producing apparent diffraction symmetry I422. The tetragonal symmetry of the unit cell and diffraction for the crystals of the LH2 complex from this species reveal that this complex is an octamer.

  20. Crystallization and X-ray diffraction analysis of human CLEC5A (MDL-1), a dengue virus receptor

    International Nuclear Information System (INIS)

    Watson, Aleksandra A.; O’Callaghan, Christopher A.

    2009-01-01

    Recombinant human CLEC5A was crystallized in the trigonal space group P3 1 and X-ray diffraction data were collected to 1.56 Å resolution. The human C-type lectin-like protein CLEC5A (also known as MDL-1) is expressed on the surface of myeloid cells and plays a critical role in dengue-virus-induced disease by signalling through the transmembrane adaptor protein DAP12. The C-type lectin-like domain of CLEC5A was expressed in Escherichia coli, refolded and purified. Recombinant CLEC5A crystals were grown by sitting-drop vapour diffusion using polyethylene glycol 6000 as a precipitant. After optimization, crystals were grown which diffracted to 1.56 Å using synchrotron radiation. The results presented in this paper suggest that crystals producing diffraction of this quality will be suitable for structural determination of human CLEC5A

  1. Modified Statistical Dynamical Diffraction Theory: A Novel Metrological Analysis Method for Partially Relaxed and Defective Carbon-doped Silicon and Silicon Germanium Heterostructures

    Science.gov (United States)

    Shreeman, Paul K.

    The statistical dynamical diffraction theory, which has been initially developed by late Kato remained in obscurity for many years due to intense and difficult mathematical treatment that proved to be quite challenging to implement and apply. With assistance of many authors in past (including Bushuev, Pavlov, Pungeov, and among the others), it became possible to implement this unique x-ray diffraction theory that combines the kinematical (ideally imperfect) and dynamical (the characteristically perfect diffraction) into a single system of equations controlled by two factors determined by long range order and correlation function within the structure. The first stage is completed by the publication (Shreeman and Matyi, J. Appl. Cryst., 43, 550 (2010)) demonstrating the functionality of this theory with new modifications hence called modified statistical dynamical diffraction theory (mSDDT). The foundation of the theory is also incorporated into this dissertation, and the next stage of testing the model against several ion-implanted SiGe materials has been published: (Shreeman and Matyi, physica status solidi (a)208(11), 2533-2538, 2011). The dissertation with all the previous results summarized, dives into comprehensive analysis of HRXRD analyses complete with several different types of reflections (symmetrical, asymmetrical and skewed geometry). The dynamical results (with almost no defects) are compared with well-known commercial software. The defective materials, to which commercially available modeling software falls short, is then characterized and discussed in depth. The results will exemplify the power of the novel approach in the modified statistical dynamical diffraction theory: Ability to detect and measure defective structures qualitatively and quantitatively. The analysis will be compared alongside with TEM data analysis for verification and confirmation. The application of this theory will accelerate the ability to quickly characterize the relaxed

  2. Contribution to diffraction theory

    International Nuclear Information System (INIS)

    Chako, N.

    1966-11-01

    In a first part, we have given a general and detailed treatment of the modern theory of diffraction. The rigorous theory is formulated as a boundary value problem of the wave equation or Maxwell equations. However, up to the present time, such a program of treating diffraction by optical systems, even for simple optical instruments, has not been realized due to the complicated character of the boundary conditions. The recent developments show clearly the nature of the approximation of the classical theories originally due to Fresnel and Young, later formulated in a rigorous manner by Kirchhoff and Rubinowicz, respectively and, at the same time the insufficiency of these theories in explaining a number of diffraction phenomena. Furthermore, we have made a study of the limitations of the approximate theories and the recent attempts to improve these. The second part is devoted to a general mathematical treatment of the theory of diffraction of optical systems including aberrations. After a general and specific analysis of geometrical and wave aberrations along classical and modern (Nijboer) lines, we have been able to evaluate the diffraction integrals representing the image field at any point in image space explicitly, when the aberrations are small. Our formulas are the generalisations of all anterior results obtained by previous investigators. Moreover, we have discussed the Zernike-Nijboer theory of aberration and generalised it not only for rotational systems, but also for non-symmetric systems as well, including the case of non circular apertures. The extension to non-circular apertures is done by introducing orthogonal functions or polynomials over such aperture shapes. So far the results are valid for small aberrations, that is to say, where the deformation of the real wave front emerging from the optical system is less than a wave length of light or of the electromagnetic wave from the ideal wave front. If the aberrations are large, then one must employ the

  3. Crystallization and preliminary diffraction analysis of Wzi, a member of the capsule export and assembly pathway in Escherichia coli

    International Nuclear Information System (INIS)

    Bushell, Simon R.; Lou, Hubing; Wallat, Gregor D.; Beis, Konstantinos; Whitfield, Chris; Naismith, James H.

    2010-01-01

    Wzi is a membrane protein from E. coli thought to be involved in the attachment of capsular polysaccharides to the bacterial surface. This reports describes recombinant Wzi’s purification, crystallization and the results of initial diffraction studies. External polysaccharide capsules provide a physical barrier that is employed by many species of bacteria for the purposes of host evasion and persistence. Wzi is a 53 kDa outer membrane β-barrel protein that is thought to play a role in the attachment of group 1 capsular polysaccharides to the cell surface. The purification and crystallization of an Escherichia coli homologue of Wzi is reported and diffraction data from native and selenomethionine-incorporated protein crystals are presented. Crystals of C-terminally His 6 -tagged Wzi diffracted to 2.8 Å resolution. Data processing showed that the crystals belonged to the orthorhombic space group C222, with unit-cell parameters a = 128.8, b = 152.8, c = 94.4 Å, α = β = γ = 90°. A His-tagged selenomethionine-containing variant of Wzi has also been crystallized in the same space group and diffraction data have been recorded to 3.8 Å resolution. Data processing shows that the variant crystal has similar unit-cell parameters to the native crystal

  4. Cloning, recombinant production, crystallization and preliminary X-ray diffraction analysis of SDF2-like protein from Arabidopsis thaliana

    International Nuclear Information System (INIS)

    Radzimanowski, Jens; Ravaud, Stephanie; Schott, Andrea; Strahl, Sabine; Sinning, Irmgard

    2009-01-01

    Overexpression, purification, crystallization and preliminary X-ray diffraction of the stromal-cell-derived factor 2-like protein of Arabidopsis thaliana are reported. The crystals belonged to the space group P6 1 and diffracted to 1.95 Å resolution. The stromal-cell-derived factor 2-like protein of Arabidopsis thaliana (AtSDL) has been shown to be highly up-regulated in response to unfolded protein response (UPR) inducing reagents, suggesting that it plays a crucial role in the plant UPR pathway. AtSDL has been cloned, overexpressed, purified and crystallized using the vapour-diffusion method. Two crystal forms have been obtained under very similar conditions. The needle-shaped crystals did not diffract X-rays, while the other form diffracted to 1.95 Å resolution using a synchrotron-radiation source and belonged to the hexagonal space group P6 1 , with unit-cell parameters a = b = 96.1, c = 69.3 Å

  5. X-ray diffraction analysis of residual stresses in alumina-chromium composites and comparison with numerical simulations

    Energy Technology Data Exchange (ETDEWEB)

    Geandier, G.; Weisbecker, P.; Denis, S.; Mocellin, A. [L.S.G.2M., UMR, CNRS/INPL, Ecole des Mines de Nancy, Nancy (France); Hazotte, A. [L.S.G.2M., UMR, CNRS/INPL, Ecole des Mines de Nancy, Nancy (France); LETAM, UMR, CNRS/Metz Univ., ISGMP, Metz (France); Lebrun, J.L. [L.P.M.I., ENSAM Angers, Angers (France); Elkaim, E. [L.U.R.E., Centre Univ. Paris-Sud, Orsay (France)

    2002-07-01

    Residual stresses in alumina chromium composites have been determined using X ray synchrotron diffraction at LURE. Results show that non-negligible residual stresses exist in the composites. Mean residual stresses calculated by finite element show discrepancies with experimental values that are discussed in relation with experimental difficulties and calculation assumptions. (orig.)

  6. Quantitative X-ray diffraction analysis of development of Z phase in 12%Cr–Nb–V–N steel

    DEFF Research Database (Denmark)

    Di Nunzio, P. E.; Cipolla, L.; Vipraio, S. Tiberi

    2010-01-01

    . A quantitative determination of the volume fractions of the extracted nitrides that had formed after aging treatments at 650uC for up to 10 000 h was carried out by an X-ray diffraction procedure, based on the Rietveld approach. The investigation of the Z phase evolution by the Johnson...

  7. Preferred orientation of a naturally and experimentally deformed pyrrhotite ore by X-ray and neutron diffraction texture analysis

    International Nuclear Information System (INIS)

    Niederschlag, E.; Brokmeier, H.G.; Siemes, H.

    1994-01-01

    Two samples of polycrystalline naturally deformed hexagonal Pyrrhotite were deformed experimentally in axial compression tests with different temperatures and strain. The texture of the naturally deformed ore was investigated both by X-ray and neutron texture analyses. Texture measurements on the experimentally deformed ore were carried out by neutron diffraction. (orig.)

  8. Study on mineral components of rat calvaria by means of X-ray powder diffraction analysis and Raman microprobe spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Tamura, Norihiro [Meikai Univ., Sakado, Saitama (Japan). School of Dentistry

    2000-07-01

    The present study was designed to examine the occurrence of the precursor minerals of hydroxyapatite (HA) during the process of HA formation in the rat calvaria. Dried and powdered rat calvaria and synthetic samples, such as HA, dicalcium phosphate dihydrate (DCPD), octacalcium phosphate (OCP), ({beta}-calcium pyrophosphate) and ({beta}-tricalcium phosphate), were used. Determinations were carried out by X-ray powder diffraction and Raman microprobe spectrometry. In general, significant widening of the diffraction peaks was shown to occur after the plasma ashing was performed for the X-ray diffraction. As a result, two adjacent peaks seen normally in the diffraction angles (2 {theta}) 30-35 deg, which is a characteristic feature of HA, were found to fuse with each other, forming a widened single peak. Also, there was a tendency for the intensity of the diffraction peaks to increase with age. With regard to the effect of plasma ashing on the crystallograms of synthetic specimens, all specimens manifested sharp peak patterns except DCPD and OCP. In contrast, a widening of diffraction peaks was observed in the DCPD and OCP samples, indicating that crystallinity had changed during the pretreatment. Results obtained from both vital and synthetic samples after heat treatment at 1000 deg C were as follow: Clearcut diffraction patterns, characteristics of HA, were obtained in all of the calvaria samples. Further, {beta}-TCP was produced by heat treatment of OCP, and its pattern was detected in the samples from rats younger than 6 days of age. Amounts of {beta}-TCP in percentage were disclosed to be 40.2% in embryonal samples, 28.4% in newborn samples, and 18.6% in 6-day-old samples. But no {beta}-TCP could be detected in the 12-week-old samples, indicating that the amount of {beta}-TCP in calvaria decreased with age. We also found that ashing pretreatment did not cause any changes in the samples of HA, {beta}-CPP, and {beta}-TCP. Further, DCPD and {beta}-CPP samples shared

  9. Study on mineral components of rat calvaria by means of X-ray powder diffraction analysis and Raman microprobe spectroscopy

    International Nuclear Information System (INIS)

    Tamura, Norihiro

    2000-01-01

    The present study was designed to examine the occurrence of the precursor minerals of hydroxyapatite (HA) during the process of HA formation in the rat calvaria. Dried and powdered rat calvaria and synthetic samples, such as HA, dicalcium phosphate dihydrate (DCPD), octacalcium phosphate (OCP), (β-calcium pyrophosphate) and (β-tricalcium phosphate), were used. Determinations were carried out by X-ray powder diffraction and Raman microprobe spectrometry. In general, significant widening of the diffraction peaks was shown to occur after the plasma ashing was performed for the X-ray diffraction. As a result, two adjacent peaks seen normally in the diffraction angles (2 θ) 30-35 deg, which is a characteristic feature of HA, were found to fuse with each other, forming a widened single peak. Also, there was a tendency for the intensity of the diffraction peaks to increase with age. With regard to the effect of plasma ashing on the crystallograms of synthetic specimens, all specimens manifested sharp peak patterns except DCPD and OCP. In contrast, a widening of diffraction peaks was observed in the DCPD and OCP samples, indicating that crystallinity had changed during the pretreatment. Results obtained from both vital and synthetic samples after heat treatment at 1000 deg C were as follow: Clearcut diffraction patterns, characteristics of HA, were obtained in all of the calvaria samples. Further, β-TCP was produced by heat treatment of OCP, and its pattern was detected in the samples from rats younger than 6 days of age. Amounts of β-TCP in percentage were disclosed to be 40.2% in embryonal samples, 28.4% in newborn samples, and 18.6% in 6-day-old samples. But no β-TCP could be detected in the 12-week-old samples, indicating that the amount of β-TCP in calvaria decreased with age. We also found that ashing pretreatment did not cause any changes in the samples of HA, β-CPP, and β-TCP. Further, DCPD and β-CPP samples shared the same diffraction pattern, and OCP

  10. Application of extended-crystal diffraction techniques to the symmetry and structure analysis of 221-PbBiSrCaCuO

    International Nuclear Information System (INIS)

    Goodman, P.; Miller, P.

    1993-01-01

    The discovery of a series of layer-perovskite superconducting compounds by Maeda et al. (1988) presented a challenge for present day electron diffraction techniques, due to their common occurrence as mixed phases, and the existence of complex structural modulations of more than one type. Cowley's (1976) theory developed specifically for describing diffraction effects from layered crystals having a micro-domainal sub-structure seems particularly well suited to the task of solving these structures, while the technique of extended-crystal diffraction is shown here to be capable of providing data of sufficient precision for this analysis. The present study is made on the 221 compound of PbBiSrCaCuO. Using the above diffraction techniques it is shown that the true symmetry of the whole structure is orthorhombic, Amaa, and not monoclinic as previously assumed, and that the superlattice reflections arise as a result of a basic microdomainal constitution, rather than from a uniform and incommensurate modulation. 8 figs

  11. Cloning, overexpression, purification, crystallization and preliminary X-ray diffraction analysis of an inositol monophosphatase family protein (SAS2203) from Staphylococcus aureus MSSA476

    International Nuclear Information System (INIS)

    Bhattacharyya, Sudipta; Dutta, Debajyoti; Ghosh, Ananta Kumar; Das, Amit Kumar

    2011-01-01

    The cloning, overexpression, purification, crystallization and preliminary X-ray diffraction analysis of an inositol monophosphatase family protein (SAS2203) from S. aureus MSSA476 is reported. The gene product of the sas2203 ORF of Staphylococcus aureus MSSA476 encodes a 30 kDa molecular-weight protein with a high sequence resemblance (29% identity) to tetrameric inositol monophosphatase from Thermotoga maritima. The protein was cloned, expressed, purified to homogeneity and crystallized. Crystals appeared in several conditions and good diffraction-quality crystals were obtained from 0.2 M Li 2 SO 4 , 20% PEG 3350, 0.1 M HEPES pH 7.0 using the sitting-drop vapour-diffusion method. A complete diffraction data set was collected to 2.6 Å resolution using a Rigaku MicroMax-007 HF Cu Kα X-ray generator and a Rigaku R-AXIS IV ++ detector. The diffraction data were consistent with the orthorhombic space group P2 1 2 1 2 1 , with unit-cell parameters a = 49.98, b = 68.35, c = 143.79 Å, α = β = γ = 90°, and the crystal contained two molecules in the asymmetric unit

  12. Neutron and X-ray diffraction analysis of the effect of irradiation dose and temperature on microstructure of irradiated HT-9 steel

    International Nuclear Information System (INIS)

    Mosbrucker, P.L.; Brown, D.W.; Anderoglu, O.; Balogh, L.; Maloy, S.A.; Sisneros, T.A.; Almer, J.; Tulk, E.F.; Morgenroth, W.; Dippel, A.C.

    2013-01-01

    Material harvested from several positions within a nuclear fuel duct (the ACO-3 duct) used in a 6-year irradiation of a fuel assembly in the Fast Flux Test Reactor Facility (FFTF) was examined using neutron and high-energy X-ray diffraction. Samples with a wide range of irradiation dose and irradiation temperature history, reaching doses of up to 147 dpa and temperatures of up to 777 K, were examined. The response of various microstructural characteristics such as the weight fraction of M 23 C 6 carbides, the dislocation density and character, and the crystallographic texture were determined using whole profile analysis of the diffraction data and related to the macroscopic mechanical behavior. For instance, the dislocation density was observed to be intimately linked with observed flow strength of the irradiated materials, following the Taylor law. In general, at the high doses studied in this work, the irradiation temperature is the predominant controlling factor of the dislocation density and, thus, the flow strength of the irradiated material. The results, representing some of the first diffraction work done on samples exposed to such a high received dose, demonstrate how non-destructive and stand-off diffraction techniques can be used to characterize irradiation induced microstructure and at least estimate mechanical properties in irradiated materials without exposing workers to radiation hazards

  13. X-ray diffraction analysis and MO calculations of 1H-tetrazole; 1H-tetorazoru no Xsen kessho kozo kaiseki to bunshi kido keisan

    Energy Technology Data Exchange (ETDEWEB)

    Ono, Yoshio.; Akutsu, Yoshiaki.; Arai, Mitsuru.; Tamura, Masamitsu. [The University of Tokyo, Tokyo (Japan). School of Engineering; Matsunaga, Takehiro. [National Institute of Materials and Chemical Research, Tsukuba (Japan)

    1999-02-28

    The X-ray diffraction analysis and the MO calculations of 1H-tetrazole were carried out, in order to explain its high stability. From the X-ray diffraction analysis, five bonds in the ring have intermediate lengths between single and double bond lengths. Therefore, 1H-tetrazole is quite stable because of its aromaticity. The N1-C5 distance of 1.315A is significantly short. The molecular structure which was calculated by the ab initio MO calculation of one 1H-tetrazole molecule at MP2/6-31G* level, showed a good agreement with our experimental one, except for the abnormal short N1-C5 distance. From the calculations of dimers and trimers, 1H-tetrazole is shown to be stabilized by a strong intermolecular electrostatic interaction between the protons and the delocalized electrons over the ring. (author)

  14. Diffractive production and hadron structure

    International Nuclear Information System (INIS)

    Nussinov, S.; Szwed, J.

    1979-01-01

    Analysis of diffractive production on nuclei implied cross sections of the diffractively produced system on nucleons which are smaller than the corresponding projectile nucleon cross sections. A natural explanation for this feature is provided in the Good-Walker coherent production formalism. A specific realization of the Good-Walker formalism stated in terms of quarks and connecting electric flux tubes and some ensuing consequences are also discussed briefly. (Auth.)

  15. Aluminium incorporation in AlxGa1-xN/GaN heterostructures: A comparative study by ion beam analysis and X-ray diffraction

    International Nuclear Information System (INIS)

    Redondo-Cubero, A.; Gago, R.; Gonzalez-Posada, F.; Kreissig, U.; Di Forte Poisson, M.-A.; Brana, A.F.; Munoz, E.

    2008-01-01

    The Al content in Al x Ga 1-x N/GaN heterostructures has been determined by X-ray diffraction (XRD) and contrasted with absolute measurements from ion beam analysis (IBA) methods. For this purpose, samples with 0.1 0.2. The assessment of Al incorporation by XRD is quite reliable regarding the average value along the sample thickness. However, XRD analysis tends to overestimate the Al fraction at low contents, which is attributed to the presence of strain within the layer. For the highest Al incorporation, IBA detects a certain Al in-depth compositional profile that should be considered for better XRD data analysis

  16. Identification and characterization of historical pigments with x-ray diffraction analysis (XRD), x-ray fluorescence analysis (XRA) and Fourier transformed infrared spectroscopy (FTIR)

    International Nuclear Information System (INIS)

    Hochleitner, B.

    2002-11-01

    This thesis presents a systematic characterization of historical inorganic pigments with respect to their crystallographic structure, main components, and trade elements, utilizing three complementary methods. The results are compiled in a computer-database containing the experimentally obtained information. The specimens examined in this study originate from a collection of 19th and 20th century pigments, dyes and binders with a wide variety of colors and materials at the Institute of Natural Sciences and Technologies in Art of the Academy of Fine Arts in Vienna. Approximately 400 different inorganic pigments were analysed for this first study of its kind by combining the experimental techniques explained in the next paragraph. For analyzing the inorganic pigments three different methods were applied: x-ray diffraction (XRD), x-ray fluorescence (XRF) and fourier-transformed infrared spectroscopy (FTIR) proved to be suitable techniques to identify and characterize the composition of the materials. The experimental work was focused on x-ray diffraction to detect the main components and to perform phase analysis for the identification of the crystallographic structure. To facilitate the analysis of the diffractograms and investigate differences in the elemental composition, XRF-measurements were carried out and complemented by FTIR-spectroscopy. The latter technique supports the identification of organic components of the samples and both ease phase analysis. In some cases, the obtained results show remarkable differences in composition for pigments having the same trade name. These differences consist either with respect to the identified elements or added components, such as pure white pigments. However, in most cases the chemical structure of the phase determining the color of the relevant pigment group was similar. Knowledge of the composition of the originally used pigments is of great importance for the restoration and conservation of art objects. In order to

  17. Isolation, crystallization and preliminary X-ray diffraction analysis of l-amino-acid oxidase from Vipera ammodytes ammodytes venom

    International Nuclear Information System (INIS)

    Georgieva, Dessislava; Kardas, Anna; Buck, Friedrich; Perbandt, Markus; Betzel, Christian

    2008-01-01

    A novel l-amino-acid oxidase was isolated from V. ammodytes ammodytes venom and crystallized. The solution conditions under which the protein sample was monodisperse were optimized using dynamic light scattering prior to crystallization. Preliminary diffraction data were collected to 2.6 Å resolution. l-Amino-acid oxidase from the venom of Vipera ammodytes ammodytes, the most venomous snake in Europe, was isolated and crystallized using the sitting-drop vapour-diffusion method. The solution conditions under which the protein sample was monodisperse were optimized using dynamic light scattering prior to crystallization. The crystals belonged to space group C2, with unit-cell parameters a = 198.37, b = 96.38, c = 109.11 Å, β = 92.56°. Initial diffraction data were collected to 2.6 Å resolution. The calculated Matthews coefficient is approximately 2.6 Å 3 Da −1 assuming the presence of four molecules in the asymmetric unit

  18. Crystallization and preliminary X-ray diffraction analysis of a tRNASer acceptor-stem microhelix

    International Nuclear Information System (INIS)

    Förster, Charlotte; Krauss, Norbert; Brauer, Arnd B. E.; Szkaradkiewicz, Karol; Brode, Svenja; Hennig, Klaus; Fürste, Jens P.; Perbandt, Markus; Betzel, Christian; Erdmann, Volker A.

    2006-01-01

    In order to investigate tRNA identity elements, an elongator tRNA Ser acceptor-stem helix was crystallized and a data set was collected to 1.8 Å resolution aiming at a comparison with the corresponding region in suppressor tRNA Sec . In order to understand elongator tRNA Ser and suppressor tRNA Sec identity elements, the respective acceptor-stem helices have been synthesized and crystallized in order to analyse and compare their structures in detail at high resolution. The synthesis, crystallization and preliminary X-ray diffraction results for a seven-base-pair tRNA Ser acceptor-stem helix are presented here. Diffraction data were collected to 1.8 Å, applying synchrotron radiation and cryogenic cooling. The crystals belong to the monoclinic space group C2, with unit-cell parameters a = 36.14, b = 38.96, c = 30.81 Å, β = 110.69°

  19. Cloning, expression, purification, crystallization and preliminary X-ray diffraction analysis of SAICAR synthase from Streptococcus suis serotype 2

    International Nuclear Information System (INIS)

    Cheng, Xia; Lu, Guangwen; Qi, Jianxun; Cheng, Hao; Gao, Feng; Wang, Jundong; Yan, Jinghua

    2010-01-01

    Crystals of SAICAR synthase from S. suis serotype 2 were obtained in the presence of 40 mM aspartic acid substrate; they belonged to space group P2 and diffracted to 2.8 Å resolution. Phosphoribosylaminoimidazole-succinocarboxamide synthase (SAICAR synthase) plays an essential role in the de novo biosynthesis of purine nucleotides. In this study, the SAICAR synthase from Streptococcus suis was cloned and overexpressed in Escherichia coli. The subsequent product was purified and crystallized using the hanging-drop vapour-diffusion method. The crystals diffracted to 2.8 Å resolution and belonged to space group P2, with unit-cell parameters a = 70.2, b = 52.2, c = 153.9 Å, β = 102.8°

  20. The macromolecular complex of ICP and falcipain-2 from Plasmodium: preparation, crystallization and preliminary X-ray diffraction analysis

    International Nuclear Information System (INIS)

    Hansen, Guido; Schwarzloh, Britta; Rennenberg, Annika; Heussler, Volker T.; Hilgenfeld, Rolf

    2011-01-01

    The macromolecular complex of ICP (inhibitor of cysteine proteases) from P. berghei and falcipain-2 from P. falciparum has been prepared and crystallized, and a diffraction data set has been collected to a resolution of 2.6 Å. The malaria parasite Plasmodium depends on the tight control of cysteine-protease activity throughout its life cycle. Recently, the characterization of a new class of potent inhibitors of cysteine proteases (ICPs) secreted by Plasmodium has been reported. Here, the recombinant production, purification and crystallization of the inhibitory C-terminal domain of ICP from P. berghei in complex with the P. falciparum haemoglobinase falcipain-2 is described. The 1:1 complex was crystallized in space group P4 3 , with unit-cell parameters a = b = 71.15, c = 120.09 Å. A complete diffraction data set was collected to a resolution of 2.6 Å

  1. Overproduction, purification and preliminary X-ray diffraction analysis of a sulfotransferase from Mycobacterium tuberculosis H37Rv

    International Nuclear Information System (INIS)

    Tanaka, Shotaro; Moriizumi, Yuuji; Kimura, Makoto; Kakuta, Yoshimitsu

    2004-01-01

    A sulfotransferase from M. tuberculosis was crystallized and preliminarily analyzed using X-ray diffraction. Sulfotransferase STF1 from the Mycobacterium tuberculosis H37Rv genome was overproduced in Escherichia coli, purified and crystallized using the hanging-drop vapour-diffusion method. The crystals diffract to 1.5 Å resolution using synchrotron radiation at SPring-8. The crystals are monoclinic and belong to space group P2 1 , with unit-cell parameters a = 40.86, b = 95.76, c = 48.04 Å, β = 106.43°. The calculated Matthews coefficient is approximately 2.1 Å 3 Da −1 assuming the presence of one molecule of STF1 in the asymmetric unit. A substrate-binding assay using a PAP–agarose column suggests that STF1 exhibits sulfotransferase activity

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

    International Nuclear Information System (INIS)

    Wood, S. J.; Li, X.-L.; Cotta, M. A.; Biely, P.; Duke, N. E. C.; Schiffer, M.; Pokkuluri, P. R.

    2008-01-01

    The catalytic domain of the glucuronoyl esterase from H. jecorina was overexpresssed, purified and crystallized in space group P2 1 2 1 2 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 1 2 1 2 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

  3. 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.

  4. Crystallization and preliminary X-ray diffraction analysis of salutaridine reductase from the opium poppy Papaver somniferum

    International Nuclear Information System (INIS)

    Higashi, Yasuhiro; Smith, Thomas J.; Jez, Joseph M.; Kutchan, Toni M.

    2010-01-01

    Recombinant P. somniferum salutaridine reductase (SalR) was purified and crystallized with NADPH using the hanging-drop vapor-diffusion method. Crystals of the SalR–NADPH complex diffracted X-rays to a resolution of 1.9 Å. The opium poppy Papaver somniferum is the source of the narcotic analgesics morphine and codeine. Salutaridine reductase (SalR; EC 1.1.1.248) reduces the C-7 keto group of salutaridine to the C-7 (S)-hydroxyl group of salutaridinol in the biosynthetic pathway that leads to morphine in the opium poppy plant. P. somniferum SalR was overproduced in Escherichia coli and purified using cobalt-affinity and size-exclusion chromatography. Hexagonal crystals belonging to space group P6 4 22 or P6 2 22 were obtained using ammonium sulfate as precipitant and diffracted to a resolution of 1.9 Å

  5. Expression, purification, crystallization and preliminary X-ray diffraction analysis of carbonyl reductase from Candida parapsilosis ATCC 7330

    International Nuclear Information System (INIS)

    Aggarwal, Nidhi; Mandal, P. K.; Gautham, Namasivayam; Chadha, Anju

    2013-01-01

    The expression, purification, crystallization, preliminary X-ray diffraction and molecular-replacement studies on C. parapsilosis carbonyl reductase are reported. The NAD(P)H-dependent carbonyl reductase from Candida parapsilosis ATCC 7330 catalyses the asymmetric reduction of ethyl 4-phenyl-2-oxobutanoate to ethyl (R)-4-phenyl-2-hydroxybutanoate, a precursor of angiotensin-converting enzyme inhibitors such as Cilazapril and Benazepril. The carbonyl reductase was expressed in Escherichia coli and purified by GST-affinity and size-exclusion chromatography. Crystals were obtained by the hanging-drop vapour-diffusion method and diffracted to 1.86 Å resolution. The asymmetric unit contained two molecules of carbonyl reductase, with a solvent content of 48%. The structure was solved by molecular replacement using cinnamyl alcohol dehydrogenase from Saccharomyces cerevisiae as a search model

  6. Cloning, expression, purification, crystallization and preliminary X-ray diffraction analysis of glyoxalase I from Leishmania infantum

    International Nuclear Information System (INIS)

    Barata, Lídia; Sousa Silva, Marta; Schuldt, Linda; Costa, Gonçalo da; Tomás, Ana M.; Ferreira, António E. N.; Weiss, Manfred S.; Ponces Freire, Ana; Cordeiro, Carlos

    2010-01-01

    Glyoxalase I from L. infantum was cloned, overexpressed in E. coli, purified and crystallized. Glyoxalase I (GLO1) is the first of the two glyoxalase-pathway enzymes. It catalyzes the formation of S-d-lactoyltrypanothione from the non-enzymatically formed hemithioacetal of methylglyoxal and reduced trypanothione. In order to understand its substrate binding and catalytic mechanism, GLO1 from Leishmania infantum was cloned, overexpressed in Escherichia coli, purified and crystallized. Two crystal forms were obtained: a cube-shaped form and a rod-shaped form. While the cube-shaped form did not diffract X-rays at all, the rod-shaped form exhibited diffraction to about 2.0 Å resolution. The crystals belonged to space group P2 1 2 1 2, with unit-cell parameters a = 130.03, b = 148.51, c = 50.63 Å and three dimers of the enzyme per asymmetric unit

  7. Quantitative low-energy electron diffraction analysis of the GaN(000-1) (1×1) reconstruction

    Czech Academy of Sciences Publication Activity Database

    Romanyuk, Olexandr; Jiříček, Petr; Paskova, T.

    2012-01-01

    Roč. 606, 7-8 (2012), s. 740-743 ISSN 0039-6028 R&D Projects: GA ČR GPP204/10/P028 Institutional research plan: CEZ:AV0Z10100521 Keywords : gallium nitride * semiconductor surfaces * quantitative low-energy electron diffraction * LEED Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.838, year: 2012

  8. 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

  9. Crystallization and preliminary X-ray diffraction analysis of recombinant phosphoribosylpyrophosphate synthetase from the Thermophilic thermus thermophilus strain HB27

    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.; Sinitsyna, E. V.; Esipov, R. S., E-mail: esipov@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)

    2017-01-15

    Phosphoribosylpyrophosphate synthetases (PRPP synthetases) are among the key enzymes essential for vital functions of organisms and are involved in the biosynthesis of purine and pyrimidine nucleotides, coenzymes, and the amino acids histidine and tryptophan. These enzymes are used in biotechnology for the combined chemoenzymatic synthesis of natural nucleotide analogs. Recombinant phosphoribosylpyrophosphate synthetase I from the thermophilic strain HB27 of the bacterium Thermus thermophilus (T. th HB27) has high thermal stability and shows maximum activity at 75°Ð¡, due to which this enzyme holds promise for biotechnological applications. In order to grow crystals and study them by X-ray crystallography, an enzyme sample, which was produced using a highly efficient producer strain, was purified by affinity and gel-filtration chromatography. The screening of crystallization conditions was performed by the vapor-diffusion technique. The crystals of the enzyme suitable for X-ray diffraction were grown by the counter-diffusion method through a gel layer. These crystals were used to collect the X-ray diffraction data set at the SPring-8 synchrotron radiation facility (Japan) to 3-Å resolution. The crystals belong to sp. gr. P2{sub 1} and have the following unitcell parameters: a = 107.7 Å, b = 112.6 Å, c = 110.2 Å, α = γ = 90°, β = 116.6°. The X-ray diffraction data set is suitable for determining the three-dimensional structure of the enzyme at 3.0-Å resolution.

  10. Crystallization and preliminary X-ray diffraction analysis of the haem-binding protein HemS from Yersinia enterocolitica

    International Nuclear Information System (INIS)

    Schneider, Sabine; Paoli, Massimo

    2005-01-01

    The haem binding protein HemS from Y. enterocolitica has been crystallized in complex with its ligand. The crystals diffracted X-rays to 2.6 Å in-house. Bacteria have evolved strategies to acquire iron from their environment. Pathogenic microbes rely on specialized proteins to ‘steal’ haem from their host and use it as an iron source. HemS is the ultimate recipient of a molecular-relay system for haem uptake in Gram-negative species, functioning as the cytosolic carrier of haem. Soluble expression and high-quality diffraction crystals were obtained for HemS from Yersinia enterocolitica. Crystals belong to the orthorhombic space group I222, with unit-cell parameters a = 74.86, b = 77.45, c = 114.09 Å, and diffract X-rays to 2.6 Å spacing in-house. Determination of the structure of the haem–HemS complex will reveal the molecular basis of haem binding

  11. Crystallization and preliminary X-ray diffraction analysis of the haem-binding protein HemS from Yersinia enterocolitica

    Energy Technology Data Exchange (ETDEWEB)

    Schneider, Sabine; Paoli, Massimo, E-mail: max.paoli@nottingham.ac.uk [School of Pharmacy and Centre for Biomolecular Sciences, University of Nottingham, University Park, Nottingham NG7 2RD (United Kingdom)

    2005-08-01

    The haem binding protein HemS from Y. enterocolitica has been crystallized in complex with its ligand. The crystals diffracted X-rays to 2.6 Å in-house. Bacteria have evolved strategies to acquire iron from their environment. Pathogenic microbes rely on specialized proteins to ‘steal’ haem from their host and use it as an iron source. HemS is the ultimate recipient of a molecular-relay system for haem uptake in Gram-negative species, functioning as the cytosolic carrier of haem. Soluble expression and high-quality diffraction crystals were obtained for HemS from Yersinia enterocolitica. Crystals belong to the orthorhombic space group I222, with unit-cell parameters a = 74.86, b = 77.45, c = 114.09 Å, and diffract X-rays to 2.6 Å spacing in-house. Determination of the structure of the haem–HemS complex will reveal the molecular basis of haem binding.

  12. Diffraction coherence in optics

    CERN Document Server

    Françon, M; Green, L L

    2013-01-01

    Diffraction: Coherence in Optics presents a detailed account of the course on Fraunhofer diffraction phenomena, studied at the Faculty of Science in Paris. The publication first elaborates on Huygens' principle and diffraction phenomena for a monochromatic point source and diffraction by an aperture of simple form. Discussions focus on diffraction at infinity and at a finite distance, simplified expressions for the field, calculation of the path difference, diffraction by a rectangular aperture, narrow slit, and circular aperture, and distribution of luminous flux in the airy spot. The book th

  13. 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.

  14. Crystallization and preliminary X-ray diffraction analysis of BipD, a virulence factor from Burkholderia pseudomallei

    Energy Technology Data Exchange (ETDEWEB)

    Knight, M. J.; Ruaux, A.; Mikolajek, H.; Erskine, P. T.; Gill, R.; Wood, S. P. [School of Biological Sciences, University of Southampton, Bassett Crescent East, Southampton SO16 7PX (United Kingdom); Wood, M. [Institute of Animal Health, Division of Environmental Microbiology, Institute for Animal Health, Compton Laboratory, Berkshire RG20 7NN (United Kingdom); Cooper, J. B., E-mail: j.b.cooper@soton.ac.uk [School of Biological Sciences, University of Southampton, Bassett Crescent East, Southampton SO16 7PX (United Kingdom)

    2006-08-01

    BipD is likely to be a component of a type-III protein secretion system (TTSS) in B. pseudomallei. Native and selenomethionyl-BipD proteins have been expressed and crystals have been obtained which diffract to 2.1 Å. Burkholderia pseudomallei, the causative agent of melioidosis, possesses a protein-secretion apparatus that is similar to those found in Salmonella and Shigella. A major function of these secretion systems is to secrete virulence-associated proteins into target cells of the host organism. The BipD gene of B. pseudomallei encodes a secreted virulence factor that is similar in sequence and most likely functionally analogous to IpaD from Shigella and SipD from Salmonella. Thus, the BipD protein is likely to be a component of a type III protein-secretion system (TTSS) in B. pseudomallei. Proteins in the same class as BipD, such as IpaD and SipD, are thought to act as extracellular chaperones to help the hydrophobic translocator proteins enter the target cell membrane, where they form a pore and might even link the translocon pore with the secretion needle. There is evidence that the translocator proteins also bind an integrin which stimulates actin-mediated insertion of the bacterium into the host-cell membrane. Native BipD has been crystallized in a monoclinic crystal form that diffracts X-rays to 2.5 Å resolution. BipD protein which incorporates selenomethionine (SeMet-BipD) has also been expressed and forms crystals which diffract to a higher resolution of 2.1 Å.

  15. Crystallization and preliminary X-ray diffraction analysis of BipD, a virulence factor from Burkholderia pseudomallei

    International Nuclear Information System (INIS)

    Knight, M. J.; Ruaux, A.; Mikolajek, H.; Erskine, P. T.; Gill, R.; Wood, S. P.; Wood, M.; Cooper, J. B.

    2006-01-01

    BipD is likely to be a component of a type-III protein secretion system (TTSS) in B. pseudomallei. Native and selenomethionyl-BipD proteins have been expressed and crystals have been obtained which diffract to 2.1 Å. Burkholderia pseudomallei, the causative agent of melioidosis, possesses a protein-secretion apparatus that is similar to those found in Salmonella and Shigella. A major function of these secretion systems is to secrete virulence-associated proteins into target cells of the host organism. The BipD gene of B. pseudomallei encodes a secreted virulence factor that is similar in sequence and most likely functionally analogous to IpaD from Shigella and SipD from Salmonella. Thus, the BipD protein is likely to be a component of a type III protein-secretion system (TTSS) in B. pseudomallei. Proteins in the same class as BipD, such as IpaD and SipD, are thought to act as extracellular chaperones to help the hydrophobic translocator proteins enter the target cell membrane, where they form a pore and might even link the translocon pore with the secretion needle. There is evidence that the translocator proteins also bind an integrin which stimulates actin-mediated insertion of the bacterium into the host-cell membrane. Native BipD has been crystallized in a monoclinic crystal form that diffracts X-rays to 2.5 Å resolution. BipD protein which incorporates selenomethionine (SeMet-BipD) has also been expressed and forms crystals which diffract to a higher resolution of 2.1 Å

  16. miniPixD : a compact sample analysis system which combines X-ray imaging and diffraction

    International Nuclear Information System (INIS)

    Moss, Robert; Crews, Chiaki; Speller, Robert; Wilson, Matthew

    2017-01-01

    This paper introduces miniPixD : a new, compact system that utilises transmission X-ray imaging and X-ray diffraction (XRD) to locate and identify materials of interest within an otherwise opaque volume. The system and the embodied techniques have utility in security screening, medical diagnostics, non-destructive testing (NDT) and quality assurance (QA). This paper outlines the design of the system including discussion on the choice of components and presents some data from relevant samples which are compared to other energy dispersive and angular dispersive XRD techniques.

  17. Quantitative analysis of localized stresses in irradiated stainless steels using high resolution electron backscatter diffraction and molecular dynamics modeling

    International Nuclear Information System (INIS)

    Johnson, D.C.; Kuhr, B.; Farkas, D.; Was, G.S.

    2016-01-01

    Quantitative measurements of stress near dislocation channel–grain boundary (DC–GB) interaction sites were made using high resolution electron backscatter diffraction (HREBSD) and have been compared with molecular dynamics (MD) simulations. Tensile stress normal to the grain boundary was significantly elevated at discontinuous DC–GB intersections with peak magnitudes roughly an order of magnitude greater than at sites where slip transfer occurred. These results constitute the first measurement of stress amplification at DC–GB intersections and provide support to the theory that high normal stress at the grain boundary may be a key driver for the initiation of irradiation assisted stress corrosion cracks.

  18. Phase behavior in diffraction

    International Nuclear Information System (INIS)

    Checon, A.

    1983-01-01

    Theoretical formulation of a straight edge diffraction shows a phase difference of π/2 between the incoming and diffracted waves. Experiments using two straight edges do not confirm the π/2 difference but suggest that the incoming wave is in phase with the wave diffracted into the shadowed region of the edge and out of phase by a factor of π with the wave diffracted into the illuminated region. (Author) [pt

  19. Cloning, expression, purification, crystallization and preliminary X-ray diffraction analysis of succinyl-diaminopimelate desuccinylase (Rv1202, DapE) from Mycobacterium tuberculosis

    International Nuclear Information System (INIS)

    Reinhard, Linda; Mueller-Dieckmann, Jochen; Weiss, Manfred S.

    2012-01-01

    M. tuberculosis succinyl-diaminopimelate desuccinylase, the enzyme which catalyzes the seventh step of the lysine-biosynthesis pathway, has been cloned, expressed, purified and crystallized. Preliminary X-ray diffraction analysis indicated the presence of pseudo-merohedral twinning in space group P2 1 , resulting in possible emulation of space group C222 1 . Succinyl-diaminopimelate desuccinylase from Mycobacterium tuberculosis (DapE, Rv1202) has been cloned, heterologously expressed in Escherichia coli and purified using standard chromatographic techniques. Diffraction-quality crystals were obtained at acidic pH from ammonium sulfate and PEG and diffraction data were collected from two crystals to resolutions of 2.40 and 2.58 Å, respectively. The crystals belonged to the monoclinic space group P2 1 , with unit-cell parameters a = 79.7, b = 76.0, c = 82.9 Å, β = 119°. The most probable content of the asymmetric unit was two molecules of DapE, which would correspond to a solvent content of 56%. Both examined crystals turned out to be pseudo-merohedrally twinned, with twin operator −h, −k, h + l and twin fractions of approximately 0.46 and 0.16, respectively

  20. Crystallization and X-ray diffraction analysis of the Trp/amber editing site of hepatitis delta virus (+)RNA: a case of rational design

    International Nuclear Information System (INIS)

    MacElrevey, Celeste; Wedekind, Joseph E.

    2005-01-01

    Well diffracting decamer crystals of the hepatitis delta virus RNA-editing site were prepared, but exhibited merohedral twinning and base averaging owing to duplex symmetry. A longer asymmetric construct that includes additional flanking RNA sequences has been crystallized that does not appear to exhibit these defects. RNA editing by mammalian ADAR1 (Adenosine Deaminase Acting on RNA) is required for the life cycle of the hepatitis delta virus (HDV). Editing extends the single viral open reading frame to yield two protein products of alternate length. ADARs are believed to recognize double-stranded RNA substrates via a ‘structure-based’ readout mechanism. Crystals of 10-mer duplexes representing the HDV RNA-editing site diffracted to 1.35 Å resolution, but suffered from merohedral twinning and averaging of the base registry. Expansion of the construct to include two flanking 3 × 1 internal loops yielded crystals in the primitive tetragonal space group P4 1 2 1 2 or P4 3 2 1 2. X-ray diffraction data were collected to 2.8 Å resolution, revealing a unit cell with parameters a = 62.5, c = 63.5 Å. The crystallization and X-ray analysis of multiple forms of the HDV RNA-editing substrate, encounters with common RNA crystal-growth defects and a strategy to overcome these problems are reported

  1. In situ analysis of elemental depth distributions in thin films by combined evaluation of synchrotron x-ray fluorescence and diffraction

    International Nuclear Information System (INIS)

    Mainz, R.; Klenk, R.

    2011-01-01

    In this work we present a method for the in situ analysis of elemental depth distributions in thin films using a combined evaluation of synchrotron x-ray fluorescence and energy-dispersive x-ray diffraction signals. We recorded diffraction and fluorescence signals simultaneously during the reactive annealing of thin films. By means of the observed diffraction signals, the time evolution of phases in the thin films during the annealing processes can be determined. We utilized this phase information to parameterize the depth distributions of the elements in the films. The time-dependent fluorescence signals were then taken to determine the parameters representing the parameterized depth distributions. For this latter step, we numerically calculated the fluorescence intensities for a given set of depth distributions. These calculations handle polychromatic excitation and arbitrary functions of depth distributions and take into account primary and secondary fluorescence. Influences of lateral non-uniformities of the films, as well as the accuracy limits of the method, are investigated. We apply the introduced method to analyze the evolution of elemental depth distributions and to quantify the kinetic parameters during a synthesis process of CuInS 2 thin films via the reactive annealing of Cu-In precursors in a sulfur atmosphere.

  2. Purification, crystallization and preliminary X-ray diffraction analysis of inner membrane complex (IMC) subcompartment protein 1 (ISP1) from Toxoplasma gondii

    International Nuclear Information System (INIS)

    Tonkin, Michelle L.; Brown, Shannon; Beck, Josh R.; Bradley, Peter J.; Boulanger, Martin J.

    2012-01-01

    To characterize the ISP family of proteins present in apicomplexan parasites, ISP1 from T. gondii was expressed, purified and crystallized. Two crystal forms (cubic and orthorhombic) were analyzed by X-ray diffraction and data were processed to 2.05 and 2.1 Å resolution, respectively. The protozoan parasites of the Apicomplexa phylum are devastating global pathogens. Their success is largely due to phylum-specific proteins found in specialized organelles and cellular structures. The inner membrane complex (IMC) is a unique apicomplexan structure that is essential for motility, invasion and replication. The IMC subcompartment proteins (ISP) have recently been identified in Toxoplasma gondii and shown to be critical for replication, although their specific mechanisms are unknown. Structural characterization of TgISP1 was pursued in order to identify the fold adopted by the ISPs and to generate detailed insight into how this family of proteins functions during replication. An N-terminally truncated form of TgISP1 was purified from Escherichia coli, crystallized and subjected to X-ray diffraction analysis. Two crystal forms of TgISP1 belonging to space groups P4 1 32 or P4 3 32 and P2 1 2 1 2 1 diffracted to 2.05 and 2.1 Å resolution, respectively

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

    International Nuclear Information System (INIS)

    Kraschnefski, Mark J.; Scott, Stacy A.; Holloway, Gavan; Coulson, Barbara S.; Itzstein, Mark von; Blanchard, Helen

    2005-01-01

    The carbohydrate-binding component (VP8* 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* 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 2 21 and monoclinic P2 1 ) have been obtained and X-ray diffraction data have been collected, enabling determination of the VP8* 64–223 structure by molecular replacement

  4. 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.

  5. Expression, purification, crystallization and preliminary X-ray diffraction analysis of Arabidopsis thaliana cyclophilin 38 (AtCyp38)

    International Nuclear Information System (INIS)

    Vasudevan, Dileep; Gopalan, Gayathri; He, Zengyong; Luan, Sheng; Swaminathan, Kunchithapadam

    2005-01-01

    Crystallization of Arabidopsis thaliana cyclophilin 38. The crystal diffracts X-rays to 2.5 Å resolution. AtCyp38 is one of the highly divergent multidomain cyclophilins from Arabidopsis thaliana. A recombinant form of AtCyp38 (residues 83–437) was expressed in Escherichia coli and purified to homogeneity. The protein was crystallized using the vapour-batch technique with PEG 6000 and t-butanol as precipitants. Crystals of recombinant AtCyp38 diffracted X-rays to better than 2.5 Å resolution at 95 K using a synchrotron-radiation source. The crystal belongs to the C-centred orthorhombic space group C222 1 , with unit-cell parameters a = 58.2, b = 95.9, c = 167.5 Å, and contains one molecule in the asymmetric unit. The selenomethionine derivative of the AtCyp38 protein was overexpressed, purified and crystallized in the same space group and data were collected to 3.5 Å at the NSLS synchrotron. The structure is being solved by the MAD method

  6. Novel silica stabilization method for the analysis of fine nanocrystals using coherent X-ray diffraction imaging

    Energy Technology Data Exchange (ETDEWEB)

    Monteforte, Marianne; Estandarte, Ana K.; Chen, Bo; Harder, Ross; Huang, Michael H.; Robinson, Ian K.

    2016-06-23

    High-energy X-ray Bragg coherent diffraction imaging (BCDI) is a well established synchrotron-based technique used to quantitatively reconstruct the three-dimensional morphology and strain distribution in nanocrystals. The BCDI technique has become a powerful analytical tool for quantitative investigations of nanocrystals, nanotubes, nanorods and more recently biological systems. BCDI has however typically failed for fine nanocrystals in sub-100?nm size regimes ? a size routinely achievable by chemical synthesis ? despite the spatial resolution of the BCDI technique being 20?30?nm. The limitations of this technique arise from the movement of nanocrystals under illumination by the highly coherent beam, which prevents full diffraction data sets from being acquired. A solution is provided here to overcome this problem and extend the size limit of the BCDI technique, through the design of a novel stabilization method by embedding the fine nanocrystals into a silica matrix. Chemically synthesized FePt nanocrystals of maximum dimension 20?nm and AuPd nanocrystals in the size range 60?65?nm were investigated with BCDI measurement at beamline 34-ID-C of the APS, Argonne National Laboratory. Novel experimental methodologies to elucidate the presence of strain in fine nanocrystals are a necessary pre-requisite in order to better understand strain profiles in engineered nanocrystals for novel device development.

  7. Work Hardening, Dislocation Structure, and Load Partitioning in Lath Martensite Determined by In Situ Neutron Diffraction Line Profile Analysis

    Science.gov (United States)

    Harjo, Stefanus; Kawasaki, Takuro; Tomota, Yo; Gong, Wu; Aizawa, Kazuya; Tichy, Geza; Shi, Zengmin; Ungár, Tamas

    2017-09-01

    A lath martensite steel containing 0.22 mass pct carbon was analyzed in situ during tensile deformation by high-resolution time-of-flight neutron diffraction to clarify the large work-hardening behavior at the beginning of plastic deformation. The diffraction peaks in plastically deformed states exhibit asymmetries as the reflection of redistributions of the stress and dislocation densities/arrangements in two lath packets: soft packet, where the dislocation glides are favorable, and hard packet, where they are unfavorable. The dislocation density was as high as 1015 m-2 in the as-heat-treated state. During tensile straining, the load and dislocation density became different between the two lath packets. The dislocation character and arrangement varied in the hard packet but hardly changed in the soft packet. In the hard packet, dislocations that were mainly screw-type in the as-heat-treated state became primarily edge-type and rearranged towards a dipole character related to constructing cell walls. The hard packet played an important role in the work hardening in martensite, which could be understood by considering the increase in dislocation density along with the change in dislocation arrangement.

  8. Purification, crystallization and preliminary X-ray diffraction analysis of the seryl-tRNA synthetase from Candida albicans

    International Nuclear Information System (INIS)

    Rocha, Rita; Barbosa Pereira, Pedro José; Santos, Manuel A. S.; Macedo-Ribeiro, Sandra

    2010-01-01

    The seryl-tRNA synthetase from C. albicans was crystallized by the sitting-drop vapour-diffusion method using ammonium sulfate as precipitant. The crystals belonged to the hexagonal space group P6 1 22 and diffraction data were collected to 2.0 Å resolution at a synchrotron source. The seryl-tRNA synthetase (SerRS) from Candida albicans exists naturally as two isoforms resulting from ambiguity in the natural genetic code. Both enzymes were crystallized by the sitting-drop vapour-diffusion method using 3.2–3.4 M ammonium sulfate as precipitant. The crystals belonged to the hexagonal space group P6 1 22 and contained one monomer per asymmetric unit, despite the synthetase existing as a homodimer (with a molecular weight of ∼116 kDa) in solution. Diffraction data were collected to 2.0 Å resolution at a synchrotron source and the crystal structures of unliganded SerRS and of its complexes with ATP and with a seryl-adenylate analogue were solved by molecular replacement. The structure of C. albicans SerRS represents the first reported structure of a eukaryotic cytoplasmic SerRS

  9. Diffraction grating strain gauge method: error analysis and its application for the residual stress measurement in thermal barrier coatings

    Science.gov (United States)

    Yin, Yuanjie; Fan, Bozhao; He, Wei; Dai, Xianglu; Guo, Baoqiao; Xie, Huimin

    2018-03-01

    Diffraction grating strain gauge (DGSG) is an optical strain measurement method. Based on this method, a six-spot diffraction grating strain gauge (S-DGSG) system has been developed with the advantages of high and adjustable sensitivity, compact structure, and non-contact measurement. In this study, this system is applied for the residual stress measurement in thermal barrier coatings (TBCs) combining the hole-drilling method. During the experiment, the specimen’s location is supposed to be reset accurately before and after the hole-drilling, however, it is found that the rigid body displacements from the resetting process could seriously influence the measurement accuracy. In order to understand and eliminate the effects from the rigid body displacements, such as the three-dimensional (3D) rotations and the out-of-plane displacement of the grating, the measurement error of this system is systematically analyzed, and an optimized method is proposed. Moreover, a numerical experiment and a verified tensile test are conducted, and the results verify the applicability of this optimized method successfully. Finally, combining this optimized method, a residual stress measurement experiment is conducted, and the results show that this method can be applied to measure the residual stress in TBCs.

  10. Crystallization and X-ray diffraction analysis of salicylate synthase, a chorismate-utilizing enyme involved in siderophore biosynthesis

    International Nuclear Information System (INIS)

    Parsons, James F.; Shi, Katherine; Calabrese, Kelly; Ladner, Jane E.

    2006-01-01

    Salicylate synthase, which catalyzes the first step in the synthesis of the siderophore yersiniabactin, has been crystallized. Diffraction data have been collected to 2.5 Å. Bacteria have evolved elaborate schemes that help them thrive in environments where free iron is severely limited. Siderophores such as yersiniabactin are small iron-scavenging molecules that are deployed by bacteria during iron starvation. Several studies have linked siderophore production and virulence. Yersiniabactin, produced by several Enterobacteriaceae, is derived from the key metabolic intermediate chorismic acid via its conversion to salicylate by salicylate synthase. Crystals of salicylate synthase from the uropathogen Escherichia coli CFT073 have been grown by vapour diffusion using polyethylene glycol as the precipitant. The monoclinic (P2 1 ) crystals diffract to 2.5 Å. The unit-cell parameters are a = 57.27, b = 164.07, c = 59.04 Å, β = 108.8°. The solvent content of the crystals is 54% and there are two molecules of the 434-amino-acid protein in the asymmetric unit. It is anticipated that the structure will reveal key details about the reaction mechanism and the evolution of salicylate synthase

  11. Crystallization and X-ray diffraction analysis of salicylate synthase, a chorismate-utilizing enyme involved in siderophore biosynthesis

    Energy Technology Data Exchange (ETDEWEB)

    Parsons, James F., E-mail: parsonsj@umbi.umd.edu; Shi, Katherine; Calabrese, Kelly [Center for Advanced Research in Biotechnology, The University of Maryland Biotechnology Institute, 9600 Gudelsky Drive, Rockville, MD 20850 (United States); Ladner, Jane E. [Center for Advanced Research in Biotechnology, The University of Maryland Biotechnology Institute, 9600 Gudelsky Drive, Rockville, MD 20850 (United States); National Institute of Standards and Technology (United States)

    2006-03-01

    Salicylate synthase, which catalyzes the first step in the synthesis of the siderophore yersiniabactin, has been crystallized. Diffraction data have been collected to 2.5 Å. Bacteria have evolved elaborate schemes that help them thrive in environments where free iron is severely limited. Siderophores such as yersiniabactin are small iron-scavenging molecules that are deployed by bacteria during iron starvation. Several studies have linked siderophore production and virulence. Yersiniabactin, produced by several Enterobacteriaceae, is derived from the key metabolic intermediate chorismic acid via its conversion to salicylate by salicylate synthase. Crystals of salicylate synthase from the uropathogen Escherichia coli CFT073 have been grown by vapour diffusion using polyethylene glycol as the precipitant. The monoclinic (P2{sub 1}) crystals diffract to 2.5 Å. The unit-cell parameters are a = 57.27, b = 164.07, c = 59.04 Å, β = 108.8°. The solvent content of the crystals is 54% and there are two molecules of the 434-amino-acid protein in the asymmetric unit. It is anticipated that the structure will reveal key details about the reaction mechanism and the evolution of salicylate synthase.

  12. Expression, purification, crystallization and preliminary X-ray diffraction analysis of Thermotoga neapolitana β-glucosidase B

    Energy Technology Data Exchange (ETDEWEB)

    Turner, Pernilla [Department of Biotechnology, Centre for Chemistry and Chemical Engineering, Lund University, Box 124, S-221 00 Lund (Sweden); Pramhed, Anna [Department of Molecular Biophysics, Centre for Chemistry and Chemical Engineering, Lund University, Box 124, S-221 00 Lund (Sweden); Kanders, Erik; Hedström, Martin; Karlsson, Eva Nordberg, E-mail: eva.nordberg-karlsson@biotek.lu.se [Department of Biotechnology, Centre for Chemistry and Chemical Engineering, Lund University, Box 124, S-221 00 Lund (Sweden); Logan, Derek T., E-mail: eva.nordberg-karlsson@biotek.lu.se [Department of Molecular Biophysics, Centre for Chemistry and Chemical Engineering, Lund University, Box 124, S-221 00 Lund (Sweden); Department of Biotechnology, Centre for Chemistry and Chemical Engineering, Lund University, Box 124, S-221 00 Lund (Sweden)

    2007-09-01

    Here, the expression, purification, crystallization and X-ray diffraction data of a family 3 β-glucosidase from the hyperthermophilic bacterium Thermotoga neapolitana are reported. β-Glucosidases belong to families 1, 3 and 9 of the glycoside hydrolases and act on cello-oligosaccharides. Family 1 and 3 enzymes are retaining and are reported to have transglycosylation activity, which can be used to produce oligosaccharides and glycoconjugates. Family 3 enzymes are less well characterized than their family 1 homologues and to date only two crystal structures have been solved. Here, the expression, purification, crystallization and X-ray diffraction data of a family 3 β-glucosidase from the hyperthermophilic bacterium Thermotoga neapolitana are reported. Crystals of selenomethionine-substituted protein have also been grown. The crystals belong to space group C222{sub 1}, with unit-cell parameters a = 74.9, b = 127.0, c = 175.2 Å. Native data have been collected to 2.4 Å resolution and the structure has been solved to 2.7 Å using the selenomethionine MAD method. Model building and refinement of the structure are under way.

  13. Crystallization and preliminary X-ray diffraction analysis of protein 14 from Sulfolobus islandicus filamentous virus (SIFV)

    International Nuclear Information System (INIS)

    Goulet, Adeline; Spinelli, Silvia; Campanacci, Valérie; Porciero, Sophie; Blangy, Stéphanie; Garrett, Roger A.; Tilbeurgh, Herman van; Leulliot, Nicolas; Basta, Tamara; Prangishvili, David; Cambillau, Christian

    2006-01-01

    Crystals of S. islandicus filamentous virus (SIFV) protein 14 have been grown at 293 K. Crystals belong to space group P6 2 22 or P6 4 22 and diffract to a resolution of 2.95 Å. A large-scale programme has been embarked upon aiming towards the structural determination of conserved proteins from viruses infecting hyperthermophilic archaea. Here, the crystallization of protein 14 from the archaeal virus SIFV is reported. This protein, which contains 111 residues (MW 13 465 Da), was cloned and expressed in Escherichia coli with an N-terminal His 6 tag and purified to homogeneity. The tag was subsequently cleaved and the protein was crystallized using PEG 1000 or PEG 4000 as a precipitant. Large crystals were obtained of the native and the selenomethionine-labelled protein using sitting drops of 100–300 nl. Crystals belong to space group P6 2 22 or P6 4 22, with unit-cell parameters a = b = 68.1, c = 132.4 Å. Diffraction data were collected to a maximum acceptable resolution of 2.95 and 3.20 Å for the SeMet-labelled and native protein, respectively

  14. Crystallization and preliminary X-ray diffraction analysis of the putative aldose 1-epimerase YeaD from Escherichia coli

    International Nuclear Information System (INIS)

    You, Weijie; Qiu, Xiaoting; Zhang, Yujie; Ma, Jinming; Gao, Yongxiang; Zhang, Xiao; Niu, Liwen; Teng, Maikun

    2010-01-01

    The putative aldose 1-epimerase YeaD from Escherichia coli was crystallized and diffraction data were collected to a resolution of 1.9 Å. Escherichia coli YeaD (ecYeaD) is suggested to be a member of the galactose mutarotase-like superfamily. Galactose mutarotase is an enzyme that converts α-galactose to β-galactose. The known structures of these galactose mutarotase-like proteins are similar to those of galactose mutarotases, with the catalytic residues being conserved, but there are some differences between them in the substrate-binding pocket. In order to reveal the specificity of ecYeaD, a three-dimensional structure is essential. Full-length ecYeaD with an additional 6×His tag at the C-terminus was crystallized by the hanging-drop vapour-diffusion method using polyethylene glycol 4000 as a precipitant at 283 K. An X-ray diffraction data set was collected to a resolution of 1.9 Å from a single flash-cooled crystal that belonged to space group P2 1 2 1 2 1

  15. Crystallization and preliminary X-ray diffraction analysis of ybfF, a new esterase from Escherichia coli K12

    Energy Technology Data Exchange (ETDEWEB)

    Park, Suk-Youl; Lee, Sang-Hak; Lee, Jieun; Jung, Che-Hun; Kim, Jeong-Sun, E-mail: jsunkim@chonnam.ac.kr [Department of Chemistry and Institute of Basic Sciences, Chonnam National University, Gwangju 500-757 (Korea, Republic of)

    2007-12-01

    The crystallization of ybfF, a new esterase from E. coli, and the collection of diffraction data to 1.1 Å resolution are reported. The product of the recently discovered ybfF gene, which belongs to the esterase family, does not show high sequence similarity to other esterases. To provide the molecular background to the enzymatic mechanism of the ybfF esterase, the ybfF protein from Escherichia coli K12 (Ec-ybfF) was cloned, expressed and purified. The Ec-ybfF protein was crystallized from 60% Tacsimate and 0.1 M bis-Tris propane buffer pH 7.0. Diffraction data were collected to 1.10 Å resolution using synchrotron radiation. The crystal belongs to the orthorhombic space group P2{sub 1}2{sub 1}2{sub 1}, with unit-cell parameters a = 66.09, b = 90.71, c = 92.88 Å. With two Ec-ybfF molecules in the asymmetric unit, the crystal volume per unit protein weight is 2.17 Å{sup 3} Da{sup −1}, corresponding to a solvent content of 42%.

  16. Crystallization and preliminary X-ray diffraction analysis of a class II phospholipase D from Loxosceles intermedia venom

    International Nuclear Information System (INIS)

    Ullah, Anwar; Giuseppe, Priscila Oliveira de; Murakami, Mario Tyago; Trevisan-Silva, Dilza; Wille, Ana Carolina Martins; Chaves-Moreira, Daniele; Gremski, Luiza Helena; Silveira, Rafael Bertoni da; Sennf-Ribeiro, Andrea; Chaim, Olga Meiri; Veiga, Silvio Sanches; Arni, Raghuvir Krishnaswamy

    2011-01-01

    Wild-type and H12A-mutant class II phospholipase D from L. intermedia venom were crystallized; the crystals diffracted to maximum resolutions of 1.95 and 1.60 Å, respectively. Phospholipases D are the major dermonecrotic component of Loxosceles venom and catalyze the hydrolysis of phospholipids, resulting in the formation of lipid mediators such as ceramide-1-phosphate and lysophosphatidic acid which can induce pathological and biological responses. Phospholipases D can be classified into two classes depending on their catalytic efficiency and the presence of an additional disulfide bridge. In this work, both wild-type and H12A-mutant forms of the class II phospholipase D from L. intermedia venom were crystallized. Wild-type and H12A-mutant crystals were grown under very similar conditions using PEG 200 as a precipitant and belonged to space group P12 1 1, with unit-cell parameters a = 50.1, b = 49.5, c = 56.5 Å, β = 105.9°. Wild-type and H12A-mutant crystals diffracted to maximum resolutions of 1.95 and 1.60 Å, respectively

  17. Crystallization and preliminary X-ray diffraction analysis of YisP protein from Bacillus subtilis subsp. subtilis strain 168

    International Nuclear Information System (INIS)

    Hu, Yumei; Jia, Shiru; Ren, Feifei; Huang, Chun-Hsiang; Ko, Tzu-Ping; Mitchell, Douglas A.; Guo, Rey-Ting; Zheng, Yingying

    2012-01-01

    A bacteria biofilm formation involved enzyme, BsYisP, from Bacillus subtilis subsp. subtilis strain 168, was crystallized and diffracted to 1.92 Å. YisP is an enzyme involved in the pathway of biofilm formation in bacteria and is predicted to possess squalene synthase activity. A BlastP search using the YisP protein sequence from Bacillus subtilis subsp. subtilis strain 168 shows that it shares 23% identity with the dehydrosqualene synthase from Staphylococcus aureus. The YisP from B. subtilis 168 was expressed in Escherichia coli and the recombinant protein was purified and crystallized. The crystals, which belong to the orthorhombic space group P2 1 2 1 2 1 , with unit-cell parameters a = 43.966, b = 77.576, c = 91.378 Å, were obtained by the sitting-drop vapour-diffusion method and diffracted to 1.92 Å resolution. Structure determination using MAD and MIR methods is in progress

  18. [Analysis and characterization of Belamcanda chinensis with space mutagenesis breeding by X-ray fluorescence analysis and X-ray diffraction].

    Science.gov (United States)

    Guan, Ying; Ding, Xi-Feng; Wang, Wen-Jing; Guo, Xi-Hua; Zhu, Yan-Ying

    2008-02-01

    The contents of various elements in the fourth generation Belamcanda chinensis (L.) DC. with space mutagenesis breeding were analyzed and characterized. X-ray fluorescence spectrum analysis (XRF) and powder X-ray diffraction (PXRD) were applied jointly. It was found that the content of K element in the space flight mutagenesis increases 1.03 and 0.31 times, Mg enhances 1.44 and 0.06 times, but Al reduces 38.5% and 85.5% respectively compared to the contents in the ground group and the comparison group, while those of Ca, Mn and Fe enhance 0.95, 0.30 and 0.29 times respectively contrasted to the ground group. Besides, there was discovered the crystal of whewellite in the Belamcanda chinensis (L.) DC. and the content in the ground group is less than that of the outer space and the outer space group, which in turn is less than that of the comparison group. It is concluded that the contents of mineral elements indispensable to body in the space group are closer or superior to the comparison, group as compared to the ground group. In the present paper, a quick and simple appraising method is offered, which may be of great significance to the popularization of the planting outer space Chinese traditional medicine to filtrate more excellent breed and set up norm of quality appraisal.

  19. Crystallization and preliminary X-ray diffraction analysis of the Fab fragment of WO2, an antibody specific for the Aβ peptides associated with Alzheimer’s disease

    Energy Technology Data Exchange (ETDEWEB)

    Wun, Kwok S. [Biota Structural Biology Laboratory and Centre for Structural Neurobiology, St Vincent’s Institute of Medical Research, 41 Victoria Parade, Fitzroy, Victoria 3065 (Australia); Miles, Luke A. [Biota Structural Biology Laboratory and Centre for Structural Neurobiology, St Vincent’s Institute of Medical Research, 41 Victoria Parade, Fitzroy, Victoria 3065 (Australia); Department of Chemical and Biomolecular Engineering, The University of Melbourne, Victoria 3010 (Australia); Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, 30 Flemington Road, Parkville, Victoria 3010 (Australia); Crespi, Gabriela A. N. [Biota Structural Biology Laboratory and Centre for Structural Neurobiology, St Vincent’s Institute of Medical Research, 41 Victoria Parade, Fitzroy, Victoria 3065 (Australia); Wycherley, Kaye [WEHI Biotechnology Centre, La Trobe R& D Park, Bundoora, Victoria 3086 (Australia); Ascher, David B. [Biota Structural Biology Laboratory and Centre for Structural Neurobiology, St Vincent’s Institute of Medical Research, 41 Victoria Parade, Fitzroy, Victoria 3065 (Australia); Barnham, Kevin J.; Cappai, Roberto [Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, 30 Flemington Road, Parkville, Victoria 3010 (Australia); Department of Pathology, The University of Melbourne, Victoria 3010 (Australia); The Mental Health Research Institute of Victoria, Parkville, Victoria 3052 (Australia); Beyreuther, Konrad [ZMBH, University of Heidelberg, Heidelberg (Germany); Masters, Colin L. [Department of Pathology, The University of Melbourne, Victoria 3010 (Australia); The Mental Health Research Institute of Victoria, Parkville, Victoria 3052 (Australia); Parker, Michael W. [Biota Structural Biology Laboratory and Centre for Structural Neurobiology, St Vincent’s Institute of Medical Research, 41 Victoria Parade, Fitzroy, Victoria 3065 (Australia); Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, 30 Flemington Road, Parkville, Victoria 3010 (Australia); McKinstry, William J., E-mail: wjmckinstry@hotmail.com [Biota Structural Biology Laboratory and Centre for Structural Neurobiology, St Vincent’s Institute of Medical Research, 41 Victoria Parade, Fitzroy, Victoria 3065 (Australia); Department of Medicine (St Vincent’s Hospital), The University of Melbourne, 41 Victoria Parade, Fitzroy 3065 (Australia)

    2008-05-01

    Crystallization and X-ray diffraction data collection of the Fab fragment of the monoclonal antibody WO2 in the absence or presence of amyloid β peptides associated with Alzheimer’s disease are reported. The murine monoclonal antibody WO2 specifically binds the N-terminal region of the amyloid β peptide (Aβ) associated with Alzheimer’s disease. This region of Aβ has been shown to be the immunodominant B-cell epitope of the peptide and hence is considered to be a basis for the development of immunotherapeutic strategies against this prevalent cause of dementia. Structural studies have been undertaken in order to characterize the molecular basis for antibody recognition of this important epitope. Here, details of the crystallization and X-ray analysis of the Fab fragment of the unliganded WO2 antibody in two crystal forms and of the complexes that it forms with the truncated Aβ peptides Aβ{sub 1–16} and Aβ{sub 1–28} are presented. These crystals were all obtained using the hanging-drop vapour-diffusion method at 295 K. Crystals of WO2 Fab were grown in polyethylene glycol solutions containing ZnSO{sub 4}; they belonged to the orthorhombic space group P2{sub 1}2{sub 1}2{sub 1} and diffracted to 1.6 Å resolution. The complexes of WO2 Fab with either Aβ{sub 1–@}@{sub 16} or Aβ{sub 1–28} were cocrystallized from polyethylene glycol solutions. These two complex crystals grew in the same space group, P2{sub 1}2{sub 1}2{sub 1}, and diffracted to 1.6 Å resolution. A second crystal form of WO2 Fab was grown in the presence of the sparingly soluble Aβ{sub 1–42} in PEG 550 MME. This second form belonged to space group P2{sub 1} and diffracted to 1.9 Å resolution.

  20. The classification of secondary colorectal liver cancer in human biopsy samples using angular dispersive x-ray diffraction and multivariate analysis

    International Nuclear Information System (INIS)

    Theodorakou, Chrysoula; Farquharson, Michael J

    2009-01-01

    The motivation behind this study is to assess whether angular dispersive x-ray diffraction (ADXRD) data, processed using multivariate analysis techniques, can be used for classifying secondary colorectal liver cancer tissue and normal surrounding liver tissue in human liver biopsy samples. The ADXRD profiles from a total of 60 samples of normal liver tissue and colorectal liver metastases were measured using a synchrotron radiation source. The data were analysed for 56 samples using nonlinear peak-fitting software. Four peaks were fitted to all of the ADXRD profiles, and the amplitude, area, amplitude and area ratios for three of the four peaks were calculated and used for the statistical and multivariate analysis. The statistical analysis showed that there are significant differences between all the peak-fitting parameters and ratios between the normal and the diseased tissue groups. The technique of soft independent modelling of class analogy (SIMCA) was used to classify normal liver tissue and colorectal liver metastases resulting in 67% of the normal tissue samples and 60% of the secondary colorectal liver tissue samples being classified correctly. This study has shown that the ADXRD data of normal and secondary colorectal liver cancer are statistically different and x-ray diffraction data analysed using multivariate analysis have the potential to be used as a method of tissue classification.

  1. Analysis of an industrial production suspension of Bacillus lentus subtilisin crystals by powder diffraction: a powerful quality-control tool.

    Science.gov (United States)

    Frankaer, Christian G; Moroz, Olga V; Turkenburg, Johan P; Aspmo, Stein I; Thymark, Majbritt; Friis, Esben P; Stahl, Kenny; Nielsen, Jens E; Wilson, Keith S; Harris, Pernille

    2014-04-01

    A microcrystalline suspension of Bacillus lentus subtilisin (Savinase) produced during industrial large-scale production was analysed by X-ray powder diffraction (XRPD) and X-ray single-crystal diffraction (MX). XRPD established that the bulk microcrystal sample representative of the entire production suspension corresponded to space group P212121, with unit-cell parameters a = 47.65, b = 62.43, c = 75.74 Å, equivalent to those for a known orthorhombic crystal form (PDB entry 1ndq). MX using synchrotron beamlines at the Diamond Light Source with beam dimensions of 20 × 20 µm was subsequently used to study the largest crystals present in the suspension, with diffraction data being collected from two single crystals (∼20 × 20 × 60 µm) to resolutions of 1.40 and 1.57 Å, respectively. Both structures also belonged to space group P2(1)2(1)2(1), but were quite distinct from the dominant form identified by XRPD, with unit-cell parameters a = 53.04, b = 57.55, c = 71.37 Å and a = 52.72, b = 57.13, c = 65.86 Å, respectively, and refined to R = 10.8% and Rfree = 15.5% and to R = 14.1% and Rfree = 18.0%, respectively. They are also different from any of the forms previously reported in the PDB. A controlled crystallization experiment with a highly purified Savinase sample allowed the growth of single crystals of the form identified by XRPD; their structure was solved and refined to a resolution of 1.17 Å with an R of 9.2% and an Rfree of 11.8%. Thus, there are at least three polymorphs present in the production suspension, albeit with the 1ndq-like microcrystals predominating. It is shown how the two techniques can provide invaluable and complementary information for such a production suspension and it is proposed that XRPD provides an excellent quality-control tool for such suspensions.

  2. Synchrotron micro-diffraction analysis of the microstructure of cryogenically treated high performance tool steels prior to and after tempering

    Energy Technology Data Exchange (ETDEWEB)

    Xu, N.; Cavallaro, G.P. [Applied Centre for Structural and Synchrotron Studies, Mawson Lakes Blvd, University of South Australia, Mawson Lakes, South Australia 5095 (Australia); Gerson, A.R., E-mail: Andrea.Gerson@unisa.edu.au [Applied Centre for Structural and Synchrotron Studies, Mawson Lakes Blvd, University of South Australia, Mawson Lakes, South Australia 5095 (Australia)

    2010-10-15

    The phase transformation and strain changes within cryogenically (-196 deg. C) treated high performance tool steels (AISI H13) before and after tempering have been examined using both laboratory XRD and synchrotron micro-diffraction. The martensitic unit cell was found to have very low tetragonality as expected for low carbon steel. Tempering resulted in the diffusion of excess carbon out of the martensite phase and consequent unit cell shrinkage. In addition on tempering the martensite became more homogeneous as compared to the same samples prior to tempering. For cryogenically treated samples, the effect was most pronounced for the rapidly cooled sample which was the least homogenous sample prior to tempering but was the most homogenous sample after tempering. This suggests that the considerable degree of disorder resulting from rapid cryogenic cooling results in the beneficial release of micro-stresses on tempering thus possibly resulting in the improved wear resistance and durability observed for cryogenically treated tool steels.

  3. Analysis of recrystallization behavior of hot-deformed austenite reconstructed from electron backscattering diffraction orientation maps of lath martensite

    International Nuclear Information System (INIS)

    Kubota, Manabu; Ushioda, Kohsaku; Miyamoto, Goro; Furuhara, Tadashi

    2016-01-01

    The recrystallization behavior of hot-deformed austenite of a 0.55% C steel at 800 °C was investigated by a method of reconstructing the parent austenite orientation map from an electron backscattering diffraction orientation map of lath martensite. Recrystallized austenite grains were clearly distinguished from un-recrystallized austenite grains. Very good correlation was confirmed between the static recrystallization behavior investigated mechanically by double-hit compression tests and the change in austenite microstructure evaluated by the reconstruction method. The recrystallization behavior of hot-deformed 0.55% C steel at 800 °C is directly revealed and it was observed that by addition of 0.1% V the recrystallization was significantly retarded.

  4. Purification, crystallization, X-ray diffraction analysis and phasing of an engineered single-chain PvuII restriction endonuclease

    International Nuclear Information System (INIS)

    Meramveliotaki, Chrysi; Kotsifaki, Dina; Androulaki, Maria; Hountas, Athanasios; Eliopoulos, Elias; Kokkinidis, Michael

    2007-01-01

    PvuII is the first type II restriction endonuclease to be converted from its wild-type homodimeric form into an enzymatically active single-chain variant. The enzyme was crystallized and phasing was successfully performed by molecular replacement. The restriction endonuclease PvuII from Proteus vulgaris has been converted from its wild-type homodimeric form into the enzymatically active single-chain variant scPvuII by tandemly joining the two subunits through the peptide linker Gly-Ser-Gly-Gly. scPvuII, which is suitable for the development of programmed restriction endonucleases for highly specific DNA cleavage, was purified and crystallized. The crystals diffract to a resolution of 2.35 Å and belong to space group P4 2 , with unit-cell parameters a = b = 101.92, c = 100.28 Å and two molecules per asymmetric unit. Phasing was successfully performed by molecular replacement

  5. X-ray diffraction analysis of LiCu2O2 crystals with additives of silver atoms

    International Nuclear Information System (INIS)

    Sirotinkin, V. P.; Bush, A. A.; Kamentsev, K. E.; Dau, H. S.; Yakovlev, K. A.; Tishchenko, E. A.

    2015-01-01

    Silver-containing LiCu 2 O 2 crystals up to 4 × 8 × 8 mm in size were grown by the crystallization of 80(1-x)CuO · 20 x AgNO 3 · 20Li 2 CO 3 (0 ≤ x ≤ 0.5) mixture melt. According to the X-ray spectral and Rietveld X-ray diffraction data, the maximum amount of silver incorporated in the LiCu 2 O 2 structure is about 4 at % relative to the copper content. It was established that silver atoms occupy statistically crystallographic positions of lithium atoms. The incorporation of silver atoms is accompanied by a noticeable increase in parameter c of the LiCu 2 O 2 rhombic unit cell, a slight increase in parameter a, and a slight decrease in parameter b

  6. Documentation of tests on particle size methodologies for laser diffraction compared to traditional sieving and sedimentation analysis

    DEFF Research Database (Denmark)

    Rasmussen, Charlotte; Dalsgaard, Kristian

    Sieving and sedimentation analyses by pipette or hydrometer are historically the traditional methods for determining particle size distributions (PSD). A more informative and faster alternative has for years been laser diffraction (LD). From 2003 to 2013 the authors of this paper have worked...... intensively with PSD and performed various tests and investigations, using LD, sedimentation (by pipette) and sieving. The aim was to improve and understand the relationship between these various techniques, pre-treatment effects and preferably find a unifying correlation factor. As a result, method...... comparisons of LD and sieving/sedimentation are difficult, as LD is a 3D optical volume measurement, sieving is a 2D width measurement, and sedimentation is density dependent. Platy particles like clay are generally measured to be coarser than traditional methods when LD is used. For LD the clay...

  7. X-ray micro-diffraction analysis of reconstructed bone at Zr prosthetic surface with sub-micrometre spatial resolution

    International Nuclear Information System (INIS)

    Cedola, A; Stanic, V; Burghammer, M; Lagomarsino, S; Rustichelli, F; Giardino, R; Aldini, N Nicoli; Fini, M; Komlev, V; Fonzo, S Di

    2003-01-01

    The purpose of the present investigation is to demonstrate the power of the x-ray micro-diffraction technique in biological studies. In particular the reported experiment concerns the study of the interface between a Zr prosthetic device implanted in a rat femur and the newly-formed bone, with a spatial resolution of 0.5 μm. The obtained results give interesting information on the Zr deformation and on the crystallographic phase, the grain size and the orientation of the new bone. Moreover the study reveals a marked difference in the structure of the reconstructed bone with respect to the native bone, which cannot be appreciated with other techniques. (note)

  8. Synchrotron micro-diffraction analysis of the microstructure of cryogenically treated high performance tool steels prior to and after tempering

    International Nuclear Information System (INIS)

    Xu, N.; Cavallaro, G.P.; Gerson, A.R.

    2010-01-01

    The phase transformation and strain changes within cryogenically (-196 deg. C) treated high performance tool steels (AISI H13) before and after tempering have been examined using both laboratory XRD and synchrotron micro-diffraction. The martensitic unit cell was found to have very low tetragonality as expected for low carbon steel. Tempering resulted in the diffusion of excess carbon out of the martensite phase and consequent unit cell shrinkage. In addition on tempering the martensite became more homogeneous as compared to the same samples prior to tempering. For cryogenically treated samples, the effect was most pronounced for the rapidly cooled sample which was the least homogenous sample prior to tempering but was the most homogenous sample after tempering. This suggests that the considerable degree of disorder resulting from rapid cryogenic cooling results in the beneficial release of micro-stresses on tempering thus possibly resulting in the improved wear resistance and durability observed for cryogenically treated tool steels.

  9. X-ray diffraction analysis of rust layer on a weathering steel bridge with surface treatment using synchrotron radiation

    International Nuclear Information System (INIS)

    Yamashita, Masato; Hara, Shuichi; Kamimura, Takayuki; Miyuki, Hideaki; Sato, Masugu

    2007-01-01

    We have examined the structure of rust layer formed on a weathering steel bridge, to which the surface treatment, employing the effect of Cr 2 (SO 4 ) 3 sophisticatedly designed to form the protective goethite (α-FeOOH) rust layer which contains a certain amount of Cr, Cr-goethite, was applied in 1996, using X-ray diffraction at SPring-8 synchrotron radiation facility. It was shown that the formation of α-FeOOH was promoted and/or crystal growth of γ-FeOOH was suppressed by the surface treatment. The increase in the protective ability index (PAI) of the rust layer indicates that the protective goethite was predominantly formed under the effect of the surface treatment. In conclusion, it can be said that the surface treatment worked well to promote the formation of the protective goethite rust layer on the weathering steel bridge during the 10-year exposure. (author)

  10. Crystallization and preliminary X-ray diffraction analysis of a cold-adapted catalase from Vibrio salmonicida

    International Nuclear Information System (INIS)

    Riise, Ellen Kristin; Lorentzen, Marit Sjo; Helland, Ronny; Willassen, Nils Peder

    2005-01-01

    Monoclinic (P2 1 ) crystals of a His-tagged form of V. salmonicida catalase without cofactor diffract X-rays to 1.96 Å. Catalase (EC 1.11.1.6) catalyses the breakdown of hydrogen peroxide to water and molecular oxygen. Recombinant Vibrio salmonicida catalase (VSC) possesses typical cold-adapted features, with higher catalytic efficiency, lower thermal stability and a lower temperature optimum than its mesophilic counterpart from Proteus mirabilis. Crystals of VSC were produced by the hanging-drop vapour-diffusion method using ammonium sulfate as precipitant. The crystals belong to the monoclinic space group P2 1 , with unit-cell parameters a = 98.15, b = 217.76, c = 99.28 Å, β = 110.48°. Data were collected to 1.96 Å and a molecular-replacement solution was found with eight molecules in the asymmetric unit

  11. Crystallization and preliminary X-ray diffraction analysis of a cold-adapted catalase from Vibrio salmonicida

    Energy Technology Data Exchange (ETDEWEB)

    Riise, Ellen Kristin [The Norwegian Structural Biology Centre, Faculty of Science, University of Tromsø, N-9037 Tromsø (Norway); Lorentzen, Marit Sjo [Department of Molecular Biotechnology, Institute of Medical Biology, Faculty of Medicine, University of Tromsø, N-9037 Tromsø (Norway); Helland, Ronny [The Norwegian Structural Biology Centre, Faculty of Science, University of Tromsø, N-9037 Tromsø (Norway); Willassen, Nils Peder, E-mail: nilspw@fagmed.uit.no [The Norwegian Structural Biology Centre, Faculty of Science, University of Tromsø, N-9037 Tromsø (Norway); Department of Molecular Biotechnology, Institute of Medical Biology, Faculty of Medicine, University of Tromsø, N-9037 Tromsø (Norway)

    2006-01-01

    Monoclinic (P2{sub 1}) crystals of a His-tagged form of V. salmonicida catalase without cofactor diffract X-rays to 1.96 Å. Catalase (EC 1.11.1.6) catalyses the breakdown of hydrogen peroxide to water and molecular oxygen. Recombinant Vibrio salmonicida catalase (VSC) possesses typical cold-adapted features, with higher catalytic efficiency, lower thermal stability and a lower temperature optimum than its mesophilic counterpart from Proteus mirabilis. Crystals of VSC were produced by the hanging-drop vapour-diffusion method using ammonium sulfate as precipitant. The crystals belong to the monoclinic space group P2{sub 1}, with unit-cell parameters a = 98.15, b = 217.76, c = 99.28 Å, β = 110.48°. Data were collected to 1.96 Å and a molecular-replacement solution was found with eight molecules in the asymmetric unit.

  12. Purification, crystallization and preliminary X-ray diffraction analysis of the RNA-dependent RNA polymerase from Thosea asigna virus

    International Nuclear Information System (INIS)

    Ferrero, Diego; Buxaderas, Mònica; Rodriguez, José F.; Verdaguer, Núria

    2012-01-01

    The RNA-dependent RNA polymerase of Thosea asigna virus has been purified and crystallized in two different crystal forms. Preliminary characterization of P2 1 2 1 2 and C222 1 crystals is reported. Co-crystallization experiments in the presence of lutetium produced a heavy-atom derivative suitable for structure determination. Thosea asigna virus (TaV) is a positive-sense, single-stranded RNA (ssRNA) virus that belongs to the Permutotetravirus genera within the recently created Permutotetraviridae family. The genome of TaV consists of an RNA segment of about 5.700 nucleotides with two open reading frames, encoding for the replicase and capsid protein. The particular TaV replicase does not contain N7-methyl transferase and helicase domains but includes a structurally unique RNA-dependent RNA polymerase (RdRp) with a sequence permutation in the domain where the active site is anchored. This architecture is also found in double-stranded RNA viruses of the Birnaviridae family. Here we report the purification and preliminary crystallographic studies TaV RdRp. The enzyme was crystallized by the sitting-drop vapour diffusion method using PEG 8K and lithium sulfate as precipitants. Two different crystal forms were obtained: native RdRp crystallized in space group P2 1 2 1 2 and diffracts up to 2.1 Å and the RdRp-Lu 3+ derivative co-crystals belong to the C222 1 space group, diffracting to 3.0 Å resolution. The structure of TaV RdRp represents the first structure of a non-canonical RdRp from ssRNA viruses

  13. Phase and Chemical Composition Analysis on Neolithic Painted Ceramics Sherds Using Synchrotron Radiation X-Ray Powder Diffraction (SRXPD)

    International Nuclear Information System (INIS)

    Constantinescu, B.

    2003-01-01

    Full text: Synchrotron Radiation X-ray Powder Diffraction studies were performed at the wiggler beamline 1711 of MAX II Synchrotron accelerator from Lund, Sweden, in the frame of EU FPV Access to Large Scale Facilities programme. Diffraction data were collected using radiation of wavelength 1.36 A, which was detected by a Brucker system with a Smart 1000 CCD detector. The main goal of our studies was to distinguish different clays and mineral pigments of various Neolithic pottery-producing centres on Romanian territory in relation with possible inter-regional trade route connections. As main results we can mention: - identification of black pigment composition from Cucuteni (Northern Moldavia), Ariusd (South-Eastern Transylvania) and Cris-Starcevo (Oltenia) type pottery (VI - IV Millennia B. Chr.) as a combination of jacobsite, bixbyite (Manganese oxides), magnetite and goethite (Iron oxides) originary from North Moldova mineral deposits of Iacobeni (150 km up on the river Bistritza from analyzed Cucuteni archaeological sites), and as a combination of pyrolusite, magnetite and hematite for Cris-Starcevo samples, probably from local clay (enriched in Mn-Fe oxides) - identification of white pigment composition as calcite (CaCO3) for Cris- Starcevo culture sites from Central Transylvania (from the local abundant chalk deposits) and as calcium silicates mixed with illite (K, H2))Al2[(H2O, OH)2]AlSi3O10 for Cucuteni culture sites - identification of read-brown pigment composition as various mixtures of hematite - goethite - magnetite, all of local provenance - identification of all examined sherds as having local provenance for the clay The main conclusion is that during Neolithic period, the pottery workshops, largely extended on Romanian territory, used local clays but traded black mineral pigments across the Carpathian mountains (Cucuteni and Ariusd areas are separated by these mountains by easily crossed by passes along small rivers)

  14. Structure analysis of complex metallic alloys in the Eu-Ag-In system by X-ray diffraction

    International Nuclear Information System (INIS)

    Gomez, Cesar Pay; Morita, Yoshiki; Tsai, An Pang; Yamamoto, Akiji

    2009-01-01

    In this work we investigate the complex atomic structures of two CMAs in the Eu-Ag-In system, these are quasicrystal approximants and their structures are similar to those of the 1/1 and 2/1 approximants found in the Yb-Cd system. The similarities between the Yb-Cd and Eu-Ag-In systems indicate that the RE-Ag-In systems in several ways can be treated as pseudo-binary. The investigated phases however also show some interesting differences; when Cd is replaced by the elements Ag and In partial chemical disorder is introduced into the system. As a response, the positional disorder which is usually observed in certain atomic positions for these types of approximants tends to disappear. The complete structures refined from single crystal data are described in detail and the differences with other related phases are highlighted. The 2/1 approximant in the Eu-Ag-In system is the first to exhibit such a degree of structural perfection in terms of positional order, a feature which makes this phase very suitable for further studies of chemical order and also can give insight into the local structures of related disordered phases. Electron diffraction studies on the 1/1 approximant phase have previously shown the presence of weak superlattice reflections, indicating a superstructure similar to that of the related phase Eu 4 Cd 25 . However, no superlattice reflections could be observed by single crystal diffraction and it is thus concluded that the phase has a disordered average structure with possible short to medium range superlattice ordering.

  15. X-ray diffraction analysis of a human tRNAGly acceptor-stem microhelix isoacceptor at 1.18 Å resolution

    International Nuclear Information System (INIS)

    Eichert, André; Perbandt, Markus; Schreiber, Angela; Fürste, Jens P.; Betzel, Christian; Erdmann, Volker A.; Förster, Charlotte

    2008-01-01

    The tRNA Gly acceptor-stem microhelix isoacceptor from human cytoplasm was crystallized and X-ray diffraction analysis revealed diffraction to 1.18 Å resolution. The sequence of the microhelix was derived from the gene sequence with tRNA Database ID DG9990. Interest has been focused on comparative X-ray structure analyses of different tRNA Gly acceptor-stem helices. tRNA Gly /glycyl-tRNA synthetase belongs to the so-called class II system, in which the tRNA identity elements consist of simple and unique determinants that are located in the tRNA acceptor stem and the discriminator base. Comparative structure investigations of tRNA Gly microhelices provide insight into the role of tRNA identity elements. Predominant differences in the structures of glycyl-tRNA synthetases and in the tRNA identity elements between prokaryotes and eukaryotes point to divergence during the evolutionary process. Here, the crystallization and high-resolution X-ray diffraction analysis of a human tRNA Gly acceptor-stem microhelix with sequence 5′-G 1 C 2 A 3 U 4 U 5 G 6 G 7 -3′, 5′-C 66 C 67 A 68 A 69 U 70 G 71 C 72 -3′ is reported. The crystals belonged to the monoclinic space group C2, with unit-cell parameters a = 37.32, b = 37.61, c = 30.47 Å, β = 112.60° and one molecule per asymmetric unit. A data set was collected using synchrotron radiation and data were processed within the resolution range 50.0–1.18 Å. The structure was solved by molecular replacement

  16. Application of the X-ray fluorescence analysis and X-ray diffraction in geochemical studies of the Pleistocene tills from Holy Cross Mountains

    International Nuclear Information System (INIS)

    Kubala-Kukuś, A.; Ludwikowska-Kedzia, M.; Banaś, D.; Braziewicz, J.; Majewska, U.; Pajek, M.; Wudarczyk-Moćko, J.

    2013-01-01

    X-ray fluorescence analysis methods (wavelength dispersive X-ray fluorescence analysis (WDXRF) and total reflection X-ray fluorescence (TXRF)) and X-ray powder diffraction (XRPD) have been applied in complementary geochemical studies of the Pleistocene till samples. The XRPD technique gave information about the mineral composition of the analyzed samples while the WDXRF and TXRF studies allowed the fast elemental analysis. The till samples were collected from different regions of Holy Cross Mountains (located in central Poland) which are still not unambiguously described in the context of the geochemical studies of the Quaternary sediments. The analysis was concentrated on the geochemical composition of the till samples both for materials occurring on the surface (characterized by continuous weathering processes) and for samples taken from core borehole. The overriding purpose of these studies is determination of the local lithotype of the tills and its lithologic and petrographic diagnostic properties, including the chemical composition of clay and minerals found in the clay. In the presented work the experimental sets up, sample preparation procedure and measurements programme will be discussed in details. Finally, the elemental and mineral compositions will be presented for studied different groups of the samples. - Highlights: • XRF analysis and X-ray diffraction used in studies of the till samples. • The till samples were collected from different regions of Holy Cross Mountains. • The analysis concentrates both on the samples from surface and from core borehole. • The purpose is determination of the local lithotype of the tills. • The experimental setup, sample preparation, measurements and results are discussed

  17. Diffraction of polarized light on periodic structures

    International Nuclear Information System (INIS)

    Bukanina, V; Divakov, D; Tyutyunnik, A; Hohlov, A

    2012-01-01

    Periodic structures as photonic crystals are widely used in modern laser devices, communication technologies and for creating various beam splitters and filters. Diffraction gratings are applied for creating 3D television sets, DVD and Blu-ray drives and reflective structures (Berkley mirror). It is important to simulate diffraction on such structures to design optical systems with predetermined properties based on photonic crystals and diffraction gratings. Methods of simulating diffraction on periodic structures uses theory of Floquet-Bloch and rigorous coupled-wave analysis (RCWA). Current work is dedicated to analysis of photonic band gaps and simulating diffraction on one-dimensional binary diffraction grating using RCWA. The Maxwell's equations for isotropic media and constitutive relations based on the cgs system were used as a model.

  18. Crystallization and preliminary X-ray diffraction analysis of two N-terminal fragments of the DNA-cleavage domain of topoisomerase IV from Staphylococcus aureus

    Energy Technology Data Exchange (ETDEWEB)

    Carr, Stephen B., E-mail: bmbsbc@bmb.leeds.ac.uk [Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds LS2 9JT (United Kingdom); Makris, George [Omega Mediation Hellas Ltd, Clinical and Pharma Consulting, 11525 N. Psychiko, Athens (Greece); Phillips, Simon E. V.; Thomas, Christopher D. [Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds LS2 9JT (United Kingdom)

    2006-11-01

    The crystallization and data collection of topoisomerase IV from S. aureus is described. Phasing by molecular replacement proved difficult owing to the presence of translational NCS and strategies used to overcome this are discussed. DNA topoisomerase IV removes undesirable topological features from DNA molecules in order to help maintain chromosome stability. Two constructs of 56 and 59 kDa spanning the DNA-cleavage domain of the A subunit of topoisomerase IV from Staphylococcus aureus (termed GrlA56 and GrlA59) have been crystallized. Crystals were grown at 291 K using the sitting-drop vapour-diffusion technique with PEG 3350 as a precipitant. Preliminary X-ray analysis revealed that GrlA56 crystals belong to space group P2{sub 1}, diffract to a resolution of 2.9 Å and possess unit-cell parameters a = 83.6, b = 171.5, c = 87.8 Å, β = 90.1°, while crystals of GrlA59 belong to space group P2{sub 1}2{sub 1}2, with unit-cell parameters a = 41.5, b = 171.89, c = 87.9 Å. These crystals diffract to a resolution of 2.8 Å. This is the first report of the crystallization and preliminary X-ray analysis of the DNA-cleavage domain of a topoisomerase IV from a Gram-positive organism.

  19. Crystallization and preliminary X-ray diffraction analysis of two N-terminal fragments of the DNA-cleavage domain of topoisomerase IV from Staphylococcus aureus

    International Nuclear Information System (INIS)

    Carr, Stephen B.; Makris, George; Phillips, Simon E. V.; Thomas, Christopher D.

    2006-01-01

    The crystallization and data collection of topoisomerase IV from S. aureus is described. Phasing by molecular replacement proved difficult owing to the presence of translational NCS and strategies used to overcome this are discussed. DNA topoisomerase IV removes undesirable topological features from DNA molecules in order to help maintain chromosome stability. Two constructs of 56 and 59 kDa spanning the DNA-cleavage domain of the A subunit of topoisomerase IV from Staphylococcus aureus (termed GrlA56 and GrlA59) have been crystallized. Crystals were grown at 291 K using the sitting-drop vapour-diffusion technique with PEG 3350 as a precipitant. Preliminary X-ray analysis revealed that GrlA56 crystals belong to space group P2 1 , diffract to a resolution of 2.9 Å and possess unit-cell parameters a = 83.6, b = 171.5, c = 87.8 Å, β = 90.1°, while crystals of GrlA59 belong to space group P2 1 2 1 2, with unit-cell parameters a = 41.5, b = 171.89, c = 87.9 Å. These crystals diffract to a resolution of 2.8 Å. This is the first report of the crystallization and preliminary X-ray analysis of the DNA-cleavage domain of a topoisomerase IV from a Gram-positive organism

  20. Purification, crystallization and X-ray diffraction analysis of the C-terminal protease domain of Venezuelan equine encephalitis virus nsP2

    International Nuclear Information System (INIS)

    Russo, Andrew T.; Watowich, Stanley J.

    2006-01-01

    The C-terminal protease domain of Venezuelan equine encephalitis virus (VEEV) nsP2 has been overexpressed in E. coli, purified and successfully crystallized. Native crystals diffract to beyond 2.5 Å resolution and isomorphous heavy-atom derivatives suitable for phase analysis have been identified. The C-terminal region of Venezuelan equine encephalitis virus (VEEV) nsP2 is responsible for proteolytic processing of the VEEV polyprotein replication complex. This action regulates the activity of the replication complex and is essential for viral replication, thus making nsP2 a very attractive target for development of VEEV therapeutics. The 338-amino-acid C-terminal region of VEEV nsP2 has been overexpressed in Escherichia coli, purified and crystallized. Crystals diffract to beyond 2.5 Å resolution and belong to the orthorhombic space group P2 1 2 1 2 1 . Isomorphous heavy-atom derivatives suitable for phase analysis have been obtained and work on building a complete structural model is under way

  1. Purification, crystallization and X-ray diffraction analysis of the C-terminal protease domain of Venezuelan equine encephalitis virus nsP2

    Energy Technology Data Exchange (ETDEWEB)

    Russo, Andrew T.; Watowich, Stanley J., E-mail: watowich@xray.utmb.edu [Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX (United States)

    2006-06-01

    The C-terminal protease domain of Venezuelan equine encephalitis virus (VEEV) nsP2 has been overexpressed in E. coli, purified and successfully crystallized. Native crystals diffract to beyond 2.5 Å resolution and isomorphous heavy-atom derivatives suitable for phase analysis have been identified. The C-terminal region of Venezuelan equine encephalitis virus (VEEV) nsP2 is responsible for proteolytic processing of the VEEV polyprotein replication complex. This action regulates the activity of the replication complex and is essential for viral replication, thus making nsP2 a very attractive target for development of VEEV therapeutics. The 338-amino-acid C-terminal region of VEEV nsP2 has been overexpressed in Escherichia coli, purified and crystallized. Crystals diffract to beyond 2.5 Å resolution and belong to the orthorhombic space group P2{sub 1}2{sub 1}2{sub 1}. Isomorphous heavy-atom derivatives suitable for phase analysis have been obtained and work on building a complete structural model is under way.

  2. Neutron diffraction study and theoretical analysis of the antiferromagnetic order and the diffuse scattering in the layered kagome system CaBaCo2Fe2O7

    Science.gov (United States)

    Reim, J. D.; Rosén, E.; Zaharko, O.; Mostovoy, M.; Robert, J.; Valldor, M.; Schweika, W.

    2018-04-01

    The hexagonal swedenborgite, CaBaCo2Fe2O7 , is a chiral frustrated antiferromagnet, in which magnetic ions form alternating kagome and triangular layers. We observe a long-range √{3 }×√{3 } antiferromagnetic order setting in below TN=160 K by neutron diffraction on single crystals of CaBaCo2Fe2O7 . Both magnetization and polarized neutron single crystal diffraction measurements show that close to TN spins lie predominantly in the a b plane, while upon cooling the spin structure becomes increasingly canted due to Dzyaloshinskii-Moriya interactions. The ordered structure can be described and refined within the magnetic space group P 31 m' . Diffuse scattering between the magnetic peaks reveals that the spin order is partial. Monte Carlo simulations based on a Heisenberg model with two nearest-neighbor exchange interactions show a similar diffuse scattering and coexistence of the √{3 }×√{3 } order with disorder. The coexistence can be explained by the freedom to vary spins without affecting the long-range order, which gives rise to ground-state degeneracy. Polarization analysis of the magnetic peaks indicates the presence of long-period cycloidal spin correlations resulting from the broken inversion symmetry of the lattice, in agreement with our symmetry analysis.

  3. Crystallization, X-ray diffraction analysis and preliminary structure determination of the polygalacturonase PehA from Agrobacterium vitis

    International Nuclear Information System (INIS)

    Vordtriede, Paul B.; Yoder, Marilyn D.

    2008-01-01

    The acidic polygalacturonase PehA from A. vitis has been crystallized. A molecular-replacement solution indicated a right-handed parallel β-helix fold. Polygalacturonases are pectate-degrading enzymes that belong to glycoside hydrolase family 28 and hydrolyze the α-1,4 glycosidic bond between neighboring galacturonasyl residues of the homogalacturonan substrate. The acidic polygalacturonase PehA from Agrobacterium vitis was overexpressed in Escherichia coli, where it accumulated in the periplasmic fraction. It was purified to homogeneity via a two-step chromatography procedure and crystallized using the hanging-drop vapour-diffusion technique. PehA crystals belonged to space group P2 1 , with unit-cell parameters a = 52.387, b = 62.738, c = 149.165 Å, β = 89.98°. Crystals diffracted to 1.59 Å resolution and contained two molecules per asymmetric unit. An initial structure determination by molecular replacement indicated a right-handed parallel β-helix fold

  4. Crystallization and preliminary X-ray diffraction analysis of the CRISPR-Cas RNA-silencing Cmr complex.

    Science.gov (United States)

    Osawa, Takuo; Inanaga, Hideko; Numata, Tomoyuki

    2015-06-01

    Clustered regularly interspaced short palindromic repeat (CRISPR)-derived RNA (crRNA) and CRISPR-associated (Cas) proteins constitute a prokaryotic adaptive immune system (CRISPR-Cas system) that targets and degrades invading genetic elements. The type III-B CRISPR-Cas Cmr complex, composed of the six Cas proteins (Cmr1-Cmr6) and a crRNA, captures and cleaves RNA complementary to the crRNA guide sequence. Here, a Cmr1-deficient functional Cmr (CmrΔ1) complex composed of Pyrococcus furiosus Cmr2-Cmr3, Archaeoglobus fulgidus Cmr4-Cmr5-Cmr6 and the 39-mer P. furiosus 7.01-crRNA was prepared. The CmrΔ1 complex was cocrystallized with single-stranded DNA (ssDNA) complementary to the crRNA guide by the vapour-diffusion method. The crystals diffracted to 2.1 Å resolution using synchrotron radiation at the Photon Factory. The crystals belonged to the triclinic space group P1, with unit-cell parameters a = 75.5, b = 76.2, c = 139.2 Å, α = 90.3, β = 104.8, γ = 118.6°. The asymmetric unit of the crystals is expected to contain one CmrΔ1-ssDNA complex, with a Matthews coefficient of 2.03 Å(3) Da(-1) and a solvent content of 39.5%.

  5. Crystallization and X-ray diffraction analysis of the CH domain of the cotton kinesin GhKCH2

    Energy Technology Data Exchange (ETDEWEB)

    Qin, Xinghua [China Agricultural University, No. 2 Yuanmingyuanxilu, Haidian District, Beijing 100094, People’s Republic of (China); The Fourth Military Medical University, No. 169 Changlexi Road, Xincheng District, Xi’an 710032, People’s Republic of (China); Chen, Ziwei; Li, Ping; Liu, Guoqin, E-mail: liu@cau.edu.cn [China Agricultural University, No. 2 Yuanmingyuanxilu, Haidian District, Beijing 100094, People’s Republic of (China)

    2016-02-19

    The cloning, expression, purification and crystallization of the CH domain of the plant-specific kinesin GhKCH2 is reported. GhKCH2 belongs to a group of plant-specific kinesins (KCHs) containing an actin-binding calponin homology (CH) domain in the N-terminus. Previous studies revealed that the GhKCH2 CH domain (GhKCH2-CH) had a higher affinity for F-actin (K{sub d} = 0.42 ± 0.02 µM) than most other CH-domain-containing proteins. To understand the underlying mechanism, prokaryotically expressed GhKCH2-CH (amino acids 30–166) was purified and crystallized. Crystals were grown by the sitting-drop vapour-diffusion method using 0.1 M Tris–HCl pH 7.0, 20%(w/v) PEG 8000 as a precipitant. The crystals diffracted to a resolution of 2.5 Å and belonged to space group P2{sub 1}, with unit-cell parameters a = 41.57, b = 81.92, c = 83.00 Å, α = 90.00, β = 97.31, γ = 90.00°. Four molecules were found in the asymmetric unit with a Matthews coefficient of 2.22 Å{sup 3} Da{sup −1}, corresponding to a solvent content of 44.8%.

  6. Crystallization and preliminary X-ray diffraction analysis of central structure domains from mumps virus F protein

    International Nuclear Information System (INIS)

    Liu, Yueyong; Xu, Yanhui; Zhu, Jieqing; Qiu, Bingsheng; Rao, Zihe; Gao, George F.; Tien, Po

    2005-01-01

    Single crystals of the central structure domains from mumps virus F protein have been obtained by the hanging-drop vapour-diffusion method. A diffraction data set has been collected to 2.2 Å resolution. Fusion of members of the Paramyxoviridae family involves two glycoproteins: the attachment protein and the fusion protein. Changes in the fusion-protein conformation were caused by binding of the attachment protein to the cellular receptor. In the membrane-fusion process, two highly conserved heptad-repeat (HR) regions, HR1 and HR2, are believed to form a stable six-helix coiled-coil bundle. However, no crystal structure has yet been determined for this state in the mumps virus (MuV, a member of the Paramyxoviridae family). In this study, a single-chain protein consisting of two HR regions connected by a flexible amino-acid linker (named 2-Helix) was expressed, purified and crystallized by the hanging-drop vapour-diffusion method. A complete X-ray data set was obtained in-house to 2.2 Å resolution from a single crystal. The crystal belongs to space group C2, with unit-cell parameters a = 161.2, b = 60.8, c = 40.1 Å, β = 98.4°. The crystal structure will help in understanding the molecular mechanism of Paramyxoviridae family membrane fusion

  7. Influence of diopside: feldspar ratio in ceramic reactions assessed by quantitative phase analysis (X-ray diffraction - Rietveld method)

    International Nuclear Information System (INIS)

    Kuzmickas, L.; Andrade, F.R.D.; Szabo, G.A.J.; Motta, J.F.M.; Cabral Junior, M.

    2013-01-01

    White ceramics were produced with raw mixtures prepared with varying proportions of diopside-rich rock (0 to 20 wt.%) and potassic feldspar (40 to 20 wt.%), and fixed proportions of kaolinite (40 wt.%) and quartz (20 wt.%), fired in a temperature range from 1170 to 1210 deg C. The phases identified in the experimental ceramics were quartz, anorthite, mullite and glass, and their relative mass proportions were determined by X-ray diffraction (Rietveld method). The addition of diopside as a partial substitute for potassic feldspar causes the formation of a calcium silicate, analogous of the natural anorthite (CaSi 2 Al 2 O 8 ) in the ceramics, with proportional reduction in its glass and mullite contents. Water absorption and porosity of the ceramic bodies clearly decrease with increasing firing temperature, while the effect of the raw mixture composition on the physical and mechanical properties of the ceramics is less evident. Diopside-rich rock has low iron content (1.5 wt.% Fe 2 O 3 ) and, therefore, promotes white burning. (author)

  8. 2-nitrobenzohydrazide as a potent urease inhibitor: synthesis, characterization and single crystal x-ray diffraction analysis

    International Nuclear Information System (INIS)

    Abbas, N.; Khan, I.; Hameed, S.; Batool, S.

    2018-01-01

    2-Nitrobenzohydrazide was efficiently synthesized in two steps by the esterification of 2-nitrobenzoic acid followed by the treatment with hydrazine hydrate in methanol. The structure of 2-nitrobenzohydrazide was established by modern spectro-analytical techniques including FTIR, 1H and 13C-NMR spectroscopy and unequivocally confirmed by single crystal X-ray diffraction data. 2-Nitrobenzohydrazide crystallized in orthorhombic space group P 21 21 21 with unit cell dimensions a = 4.9764(4) Å, b = 12.5280 (3) Å, c = 12.8512(1) Å, α = β = γ = 90°. A combination of N‒H…N and N‒H…O hydrogen bonds stabilized the crystal packing of 3. The synthesized compound 3 was assessed as urease inhibitor against Jack bean urease and the results revealed good inhibitory potency with an IC50 value of 4.25 ± 0.08 µM. This inhibition strength was 5-fold higher compared to the reference inhibitor thiourea (IC50 = 21.00 ± 0.11 µM). The molecular docking studies of the synthesized inhibitor 3 inside the active pocket of urease revealed several important binding interactions. (author)

  9. Residual Stress Analysis of Severe Plastic Deformed Materials using the Finite Element Method and the Neutron Diffraction Method

    International Nuclear Information System (INIS)

    Kang, Mi Hyun; Seong, Back Suck; Kim, Hyoung Seop

    2009-01-01

    Severe plastic deformation (SPD) is one of the most promising top-down techniques, moving towards industrialization to fabricate bulk ultrafine grain materials. The strain distribution and deformation behavior during the ECAP (equal channel angular pressing), influenced by tool angles, friction and material behavior, was studied through experimental and numerical analyses. The residual stress of work piece which was straight before ECAP produces many serious problems in the next processing e.g. input of the work piece for the next ECAP. The bent work piece needs additional straightening or surface polishing even if the amount of bending is small, and residual stress need to be released before service applications. Residual stress, particularly tensile residual stress can be a very important factor in affecting the reliability and integrity of working parts. The formation of tensile residual stress may result in initiation of fatigue cracks, stress corrosion cracking, or other types of fracture. Hence, residual stress and resulting bending need to be controlled during ECAP. Thus, in current study the bending behavior and the residual stress of the work piece in ECAP are analyzed through experimental and finite element analyses by considering the effects of material, geometric, and processing parameters individually. The stress states in the ECAP processed work piece were measured by the non-destructive way using neutron diffraction. Efforts were made to suggest the alternate routes to reduce the residual stress and bending of work piece in ECAP

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2013-12-16

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

  11. Crystallization and preliminary X-ray diffraction analysis of the metalloregulatory protein DtxR from Thermoplasma acidophilum

    International Nuclear Information System (INIS)

    Yeo, Hyun Ku; Kang, Jina; Park, Young Woo; Sung, Jung-Suk; Lee, Jae Young

    2012-01-01

    Orthorhombic crystals of DtxR from T. acidophilum have been obtained. X-ray data were collected to 1.8 Å resolution using synchrotron radiation. The diphtheria toxin repressor (DtxR) is a metal-ion-dependent transcriptional regulator which regulates genes encoding proteins involved in metal-ion uptake to maintain metal-ion homeostasis. DtxR from Thermoplasma acidophilum was cloned and overexpressed in Escherichia coli. Crystals of N-terminally His-tagged DtxR were obtained by hanging-drop vapour diffusion and diffracted to 1.8 Å resolution. DtxR was crystallized at 296 K using polyethylene glycol 4000 as a precipitant. The crystals belonged to the orthorhombic space group P2 1 2 1 2, with unit-cell parameters a = 61.14, b = 84.61, c = 46.91 Å, α = β = γ = 90°. The asymmetric unit contained approximately one monomer of DtxR, giving a crystal volume per mass (V M ) of 2.22 Å 3 Da −1 and a solvent content of 44.6%

  12. Quantitative study of Portland cement hydration by X-Ray diffraction/Rietveld analysis and geochemical modeling

    Science.gov (United States)

    Coutelot, F.; Seaman, J. C.; Simner, S.

    2017-12-01

    In this study the hydration of Portland cements containing blast-furnace slag and type V fly ash were investigated during cement curing using X-ray diffraction, with geochemical modeling used to calculate the total volume of hydrates. The goal was to evaluate the relationship between the starting component levels and the hydrate assemblages that develop during the curing process. Blast furnace-slag levels of 60, 45 and 30 wt.% were studied in blends containing fly ash and Portland cement. Geochemical modelling described the dissolution of the clinker, and predicted quantitatively the amount of hydrates. In all cases the experiments showed the presence of C-S-H, portlandite and ettringite. The quantities of ettringite, portlandite and the amorphous phases as determined by XRD agreed well with the calculated amounts of these phases after different periods of time. These findings show that changes in the bulk composition of hydrating cements can be described by geochemical models. Such a comparison between experimental and modelled data helps to understand in more detail the active processes occurring during cement hydration.

  13. Influence of diopside: feldspar ratio in ceramic reactions assessed by quantitative phase analysis (X-ray diffraction - Rietveld method)

    Energy Technology Data Exchange (ETDEWEB)

    Kuzmickas, L.; Andrade, F.R.D.; Szabo, G.A.J. [Universidade de Sao Paulo (IGc/USP), SP (Brazil). Inst. de Geociencias. Dept. de Mineralogia e Geotecnia; Motta, J.F.M.; Cabral Junior, M., E-mail: lukuzmickas@gmail.com, E-mail: dias@usp.br, E-mail: gajszabo@usp.b, E-mail: motta.jf@gmail.com, E-mail: marsis@ipt.br [Instituto de Pesquisas Tecnologicas (IPT), Sao Paulo, SP (Brazil). Secao de Recursos Minerais e Tecnologia Ceramica

    2013-04-15

    White ceramics were produced with raw mixtures prepared with varying proportions of diopside-rich rock (0 to 20 wt.%) and potassic feldspar (40 to 20 wt.%), and fixed proportions of kaolinite (40 wt.%) and quartz (20 wt.%), fired in a temperature range from 1170 to 1210 deg C. The phases identified in the experimental ceramics were quartz, anorthite, mullite and glass, and their relative mass proportions were determined by X-ray diffraction (Rietveld method). The addition of diopside as a partial substitute for potassic feldspar causes the formation of a calcium silicate, analogous of the natural anorthite (CaSi{sub 2}Al{sub 2}O{sub 8}) in the ceramics, with proportional reduction in its glass and mullite contents. Water absorption and porosity of the ceramic bodies clearly decrease with increasing firing temperature, while the effect of the raw mixture composition on the physical and mechanical properties of the ceramics is less evident. Diopside-rich rock has low iron content (1.5 wt.% Fe{sub 2}O{sub 3}) and, therefore, promotes white burning. (author)

  14. Purification, crystallization and preliminary X-ray diffraction analysis of the Kelch-like motif region of mouse Keap1

    Energy Technology Data Exchange (ETDEWEB)

    Padmanabhan, Balasundaram; Scharlock, Maria [RIKEN Genomic Sciences Center, 1-7-22 Suehiro-cho, Tsurumi, Yokohama 230-0045 (Japan); Tong, Kit I. [Graduate School of Comprehensive Human Sciences, Center for Tsukuba Advanced Research Alliance and ERATO Environmental Research Project, University of Tsukuba, 1-1-1 Tennoudai, Tsukuba 305-8577 (Japan); Nakamura, Yoshihiro [RIKEN Genomic Sciences Center, 1-7-22 Suehiro-cho, Tsurumi, Yokohama 230-0045 (Japan); Kang, Moon-Il; Kobayashi, Akira [Graduate School of Comprehensive Human Sciences, Center for Tsukuba Advanced Research Alliance and ERATO Environmental Research Project, University of Tsukuba, 1-1-1 Tennoudai, Tsukuba 305-8577 (Japan); Matsumoto, Takehisa; Tanaka, Akiko [RIKEN Genomic Sciences Center, 1-7-22 Suehiro-cho, Tsurumi, Yokohama 230-0045 (Japan); Yamamoto, Masayuki [Graduate School of Comprehensive Human Sciences, Center for Tsukuba Advanced Research Alliance and ERATO Environmental Research Project, University of Tsukuba, 1-1-1 Tennoudai, Tsukuba 305-8577 (Japan); Yokoyama, Shigeyuki, E-mail: yokoyama@biochem.s.u-tokyo.ac.jp [RIKEN Genomic Sciences Center, 1-7-22 Suehiro-cho, Tsurumi, Yokohama 230-0045 (Japan); Cellular Signaling Laboratory and Structurome Research Group, RIKEN Harima Institute at SPring-8, 1-1-1 Kouto, Mikazuki-cho, Sayo, Hyogo 679-5148 (Japan); Department of Biophysics and Biochemistry, Graduate School of Science, University of Tokyo, Bunkyo-ku, Tokyo 113-0033 (Japan)

    2005-01-01

    Keap1-DC (Kelch/double-glycine repeat and C-terminal region) of mouse Keap1 has been overexpressed in E. coli, purified and crystallized using the vapour-diffusion method. Keap1 (Kelch-like ECH-associating protein 1) is a negative regulator of the Nrf2 transcription factor in the cytoplasm. The Kelch/DGR (double-glycine repeat) domain of Keap1 associates with Nrf2 as well as with actin filaments. A recombinant protein containing both the Kelch/DGR domain and the C-terminal region of mouse Keap1 was expressed in Escherichia coli, purified to near-homogeneity and crystallized by the sitting-drop vapour-diffusion method. The crystal belongs to space group P6{sub 1} or P6{sub 5}, with unit-cell parameters a = b = 102.95, c = 55.21 Å, and contains one molecule in the asymmetric unit. A complete diffraction data was collected to 2.25 Å resolution using an R-AXIS IV{sup ++} imaging plate mounted on an RA-Micro7 Cu Kα rotating-anode X-ray generator.

  15. Preparation and Crystal Structures of Some AIVB2IIO4 Compounds: Powder X-Ray Diffraction and Rietveld Analysis

    Directory of Open Access Journals (Sweden)

    K. Jeyadheepan

    2014-01-01

    Full Text Available The AIVB2IIO4 compounds such as cadmium tin oxide (Cd2SnO4 or CTO and zinc tin oxide (Zn2SnO4 or ZTO are synthesized by solid state reaction of the subsequent binary oxides. The synthesized powders were analyzed through the powder X-ray diffraction (PXRD. Cell search done on the PXRD patterns shows that the Cd2SnO4 crystallizes in orthorhombic structure with space group Pbam and the cell parameters as a=5.568(2 Å, b=9.894(3 Å, and c=3.193(1 Å and the Zn2SnO4 crystallizes as cubic with the space group Fd3 -m and with the cell parameter a=8.660(2 Å. Rietveld refinement was done on the PXRD patterns to get the crystal structure of the Cd2SnO4 and Zn2SnO4 and to define the site deficiency of atoms which causes the electrical properties of the materials.

  16. Crystallization and Preliminary Diffraction Analysis of the CAL PDZ Domain in Complex with a Selective Peptide Inhibitor

    Energy Technology Data Exchange (ETDEWEB)

    J Amacher; P Cushing; J Weiner; D Madden

    2011-12-31

    Cystic fibrosis (CF) is associated with loss-of-function mutations in the CF transmembrane conductance regulator (CFTR), which regulates epithelial fluid and ion homeostasis. The CFTR cytoplasmic C-terminus interacts with a number of PDZ (PSD-95/Dlg/ZO-1) proteins that modulate its intracellular trafficking and chloride-channel activity. Among these, the CFTR-associated ligand (CAL) has a negative effect on apical-membrane expression levels of the most common disease-associated mutant {Delta}F508-CFTR, making CAL a candidate target for the treatment of CF. A selective peptide inhibitor of the CAL PDZ domain (iCAL36) has recently been developed and shown to stabilize apical expression of {Delta}F508-CFTR, enhancing net chloride-channel activity, both alone and in combination with the folding corrector corr-4a. As a basis for structural studies of the CAL-iCAL36 interaction, a purification protocol has been developed that increases the oligomeric homogeneity of the protein. Here, the cocrystallization of the complex in space group P2{sub 1}2{sub 1}2{sub 1}, with unit-cell parameters a = 35.9, b = 47.7, c = 97.3 {angstrom}, is reported. The crystals diffracted to 1.4 {angstrom} resolution. Based on the calculated Matthews coefficient (1.96 {angstrom}{sup 3} Da{sup -1}), it appears that the asymmetric unit contains two complexes.

  17. Cloning, recombinant production, crystallization and preliminary X-ray diffraction analysis of a family 101 glycoside hydrolase from Streptococcus pneumoniae

    International Nuclear Information System (INIS)

    Gregg, Katie J.; Boraston, Alisdair B.

    2009-01-01

    The catalytic module of a family 101 glycoside hydrolase from S. pneumoniae was cloned, recombinantly produced and crystallized. Streptococcus pneumoniae is a serious human pathogen that is responsible for a wide range of diseases including pneumonia, meningitis, septicaemia and otitis media. The full virulence of this bacterium is reliant on carbohydrate processing and metabolism, as revealed by biochemical and genetic studies. One carbohydrate-processing enzyme is a family 101 glycoside hydrolase (SpGH101) that is responsible for catalyzing the liberation of galactosyl β1,3-N-acetyl-d-galactosamine (Galβ1,3GalNAc) α-linked to serine or threonine residues of mucin-type glycoproteins. The 124 kDa catalytic module of this enzyme (SpGH101CM) was cloned and overproduced in Escherichia coli and purified. Crystals were obtained in space group P2 1 and diffracted to 2.0 Å resolution, with unit-cell parameters a = 81.86, b = 88.91, c = 88.77 Å, β = 112.46°. SpGH101CM also qualitatively displayed good activity towards the synthetic substrate p-nitrophenyl-2-acetamido-2-deoxy-3-O-(β-d-galactopyranosyl) -α-d-galactopyranoside, which is consistent with the classification of this enzyme as an endo-α-N-acetylgalactosaminidase

  18. Crystallization and X-ray diffraction analysis of an ‘all-locked’ nucleic acid duplex derived from a tRNASer microhelix

    International Nuclear Information System (INIS)

    Behling, Katja; Eichert, André; Fürste, Jens P.; Betzel, Christian; Erdmann, Volker A.; Förster, Charlotte

    2009-01-01

    A completely ‘all-locked’ nucleic acid duplex was designed from an E. coli tRNA Ser microhelix. The helix consists exclusively of LNA building blocks and was crystallized. The crystals diffracted to 1.9 Å resolution. Modified nucleic acids are of great interest with respect to their nuclease resistance and enhanced thermostability. In therapeutical and diagnostic applications, such molecules can substitute for labile natural nucleic acids that are targeted against particular diseases or applied in gene therapy. The so-called ‘locked nucleic acids’ contain modified sugar moieties such as 2′-O,4′-C-methylene-bridged β-d-ribofuranose and are known to be very stable nucleic acid derivatives. The structure of locked nucleic acids in single or multiple LNA-substituted natural nucleic acids and in LNA–DNA or LNA–RNA heteroduplexes has been well investigated, but the X-ray structure of an ‘all-locked’ nucleic acid double helix has not been described to date. Here, the crystallization and X-ray diffraction data analysis of an ‘all-locked’ nucleic acid helix, which was designed as an LNA originating from a tRNA Ser microhelix RNA structure, is presented. The crystals belonged to space group C2, with unit-cell parameters a = 77.91, b = 40.74, c = 30.06 Å, β = 91.02°. A high-resolution and a low-resolution data set were recorded, with the high-resolution data showing diffraction to 1.9 Å resolution. The crystals contained two double helices per asymmetric unit, with a Matthews coefficient of 2.48 Å 3 Da −1 and a solvent content of 66.49% for the merged data

  19. Comparative studies of laser annealing technique and furnace annealing by X-ray diffraction and Raman analysis of lithium manganese oxide thin films for lithium-ion batteries

    International Nuclear Information System (INIS)

    Pröll, J.; Weidler, P.G.; Kohler, R.; Mangang, A.; Heißler, S.; Seifert, H.J.; Pfleging, W.

    2013-01-01

    The structure and phase formations of radio frequency magnetron sputtered lithium manganese oxide thin films (Li 1.1 Mn 1.9 O 4 ) under ambient air were studied. The influence of laser annealing and furnace annealing, respectively, on the bulk structure and surface phases was compared by using ex-situ X-ray diffraction and Raman analysis. Laser annealing technique formed a dominant (440)-reflection, furnace annealing led to both, (111)- and (440)-reflections within a cubic symmetry (S.G. Fd3m (227)). Additionally, in-situ Raman and in-situ X-ray diffraction were applied for online detection of phase transformation temperatures. In-situ X-ray diffraction measurements clearly identified the starting temperature for the (111)- and (440)-reflections around 525 °C and 400 °C, respectively. The 2θ Bragg peak positions of the characteristic (111)- and (440)-reflections were in good agreement with those obtained through conventional furnace annealing. Laser annealing of lithium manganese oxide films provided a quick and efficient technique and delivered a dominant (440)-reflection which showed the expected electrochemical behavior of the well-known two-step de-/intercalation process of lithium-ions into the cubic spinel structure within galvanostatic testing and cyclic voltammetry. - Highlights: ► Formation of cubic spinel-like phase of Li–Mn–O thin films by rapid laser annealing ► Laser annealing at 680 °C and 100 s was demonstrated as quick crystallization method. ► 400 °C was identified as characteristic onset temperature for (440)-reflex formation

  20. Expression, purification, crystallization and preliminary X-ray diffraction analysis of grass carp β{sub 2}-microglobulin

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Weihong [Department of Microbiology and Immunology, College of Veterinary Medicine, China Agricultural University, Beijing 100094 (China); Chu, Fuliang [Center for Molecular Immunology, Institute of Microbiology, Chinese Academy of Sciences (CAS), Beijing 100080 (China); Graduate School, Chinese Academy of Sciences, Beijing 100049 (China); Peng, Hao [Center for Molecular Immunology, Institute of Microbiology, Chinese Academy of Sciences (CAS), Beijing 100080 (China); Zhang, Jianhua [Department of Microbiology and Immunology, College of Veterinary Medicine, China Agricultural University, Beijing 100094 (China); Qi, Jianxun; Jiang, Fan [Institute of Physics, Chinese Academy of Sciences, Beijing 100080 (China); Xia, Chun, E-mail: xiachun@cau.edu.cn [Department of Microbiology and Immunology, College of Veterinary Medicine, China Agricultural University, Beijing 100094 (China); Gao, Feng, E-mail: xiachun@cau.edu.cn [Center for Molecular Immunology, Institute of Microbiology, Chinese Academy of Sciences (CAS), Beijing 100080 (China); Department of Microbiology and Immunology, College of Veterinary Medicine, China Agricultural University, Beijing 100094 (China)

    2008-03-01

    Grass carp β{sub 2}-microglobulin was expressed in E. coli, purified to homogeneity and crystallized using the hanging-drop vapour-diffusion method with PEG 2K as precipitant. The crystals obtained belong to the orthorhombic space group P2{sub 1}2{sub 1}2{sub 1}, with unit-cell parameters a = 38.72, b = 40.65, c = 71.12 Å. β{sub 2}-Microglobulin (β{sub 2}m) is an essential subunit of MHC I molecules; it stabilizes the structure of MHC I and plays a pivotal role in coreceptor recognition. To date, structures of β{sub 2}m have been solved for three different mammals: human, mouse and cattle. In order to illuminate the molecular evolutionary origin of β2m, an understanding of its structure in lower vertebrates becomes important. Here, grass carp (Ctenopharyngodon idellus) β{sub 2}m (Ctid-β{sub 2}m) was expressed, purified and crystallized. Diffraction data were collected to a resolution of 2.5 Å. The crystal belongs to space group P2{sub 1}2{sub 1}2{sub 1}, with unit-cell parameters a = 38.72, b = 40.65, c = 71.12 Å. The Matthews coefficient and the solvent content were calculated to be 2.56 Å Da{sup −1} and 52.07%, respectively, for one molecule per asymmetric unit. The structure has been solved by molecular replacement using monomeric human β{sub 2}m as a model.

  1. On-line and in-situ x-ray diffraction analysis of the crystallisation of important pharmaceutical materials

    International Nuclear Information System (INIS)

    Hastings, S.

    1999-01-01

    Full text: The crystallisation process is an important unit operation for the separation and purification of many chemical products, particularly in the pharmaceutical industry. Variations in the conditions of crystallisation can lead to the formation of different polymorphic forms which are often meta-stable phases which results in phase conversion at different rates to the stable form. Our group, in collaboration with many industrial sponsors, have developed a number of online techniques which help to optimise the processing conditions of many of these specialty materials. In particular, on-line and in-situ X-ray diffraction (XRD) has been used to monitor the crystallisation of pharmaceutical materials. Several novel in-situ X-ray cells have been developed, in particular; a solution cell, which allows us to control and hence optimise crystallographic conditions such as temperature and pH whilst monitoring the crystal structure of the sample as it crystallises from solution. In conjunction with XRD data information on turbidity (% light transmittance) is taken to analyse solvent-mediated crystallisation. This technique gives information on the temperatures at which the system crystallises and dissolves. From this the meta-stable zone width (MSZW) can be calculated and then directly related to the crystal structure of the particles formed. The current system being studied is the crystallisation of stearic acid, a common pharmaceutical excipient, in various polar and non-polar solvents in order to ascertain the effect that the polarity of the solvent has on the polymorphic form crystallised. By combining such kinetic assessment with measurements of resulting particle structure the potential to optimise the process to produce optimal particle properties is obtainable. Copyright (1999) Australian X-ray Analytical Association Inc

  2. Light-distortion analysis as a possible indicator of visual quality after refractive lens exchange with diffractive multifocal intraocular lenses.

    Science.gov (United States)

    Brito, Pedro; Salgado-Borges, José; Neves, Helena; Gonzalez-Meijome, José; Monteiro, Manuel

    2015-03-01

    To study the perception of light distortion after refractive lens exchange (RLE) with diffractive multifocal intraocular lenses (IOLs). Clínica Oftalmológica das Antas, Porto, Portugal. Retrospective comparative study. Refractive lens exchange was performed with implantation of an AT Lisa 839M (trifocal) or 909MP (bifocal toric) IOL, the latter if corneal astigmatism was more than 0.75 diopter (D). The postoperative visual and refractive outcomes were evaluated. A prototype light-distortion analyzer was used to quantify the postoperative light-distortion indices. A control group of eyes in which a Tecnis ZCB00 1-piece monofocal IOL was implanted had the same examinations. A trifocal or bifocal toric IOL was implanted in 66 eyes. The control IOL was implanted in 18 eyes. All 3 groups obtained a significant improvement in uncorrected distance visual acuity (UDVA) (P refractive cylinder was less than 1.00 D in 86.7% of cases with the toric IOL. The mean light-distortion index was significantly higher in the multifocal IOL groups than in the monofocal group (P light-distortion index and CDVA. The multifocal IOLs provided excellent UDVA and functional UNVA despite increased light-distortion indices. The light-distortion analyzer reliably quantified a subjective component of vision distinct from visual acuity; it may become a useful adjunct in the evaluation of visual quality obtained with multifocal IOLs. No author has a financial or proprietary interest in any material or method mentioned. Copyright © 2015 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

  3. Tensometry technique for X-ray diffraction in applied analysis of welding; Tensometria por tecnica de difracao de raios X aplicada na analise de soldagens

    Energy Technology Data Exchange (ETDEWEB)

    Turibus, S.N.; Caldas, F.C.M.; Miranda, D.M.; Monine, V.I.; Assis, J.T., E-mail: snturibus@iprj.uerj.b [Universidade do Estado do Rio de Janeiro (IPRJ/UERJ), Nova Friburgo, RJ (Brazil). Inst. Politecnico

    2010-07-01

    This paper presents the analysis of residual stress introduced in welding process. As the stress in a material can induce damages, it is necessary to have a method to identify this residual stress state. For this it was used the non-destructive X-ray diffraction technique to analyze two plates from A36 steel jointed by metal inert gas (MIG) welding. The stress measurements were made by the sin{sup 2{psi}} method in weld region of steel plates including analysis of longitudinal and transverse residual stresses in fusion zone, heat affected zone (HAZ) and base metal. To determine the stress distribution along the depth of the welded material it was used removing of superficial layers made by electropolishing. (author)

  4. Quality regularities of dynamic X-ray diffraction in superlattices and films with variable gradient of deformation based on analysis of types of Takagi equation solutions

    International Nuclear Information System (INIS)

    Dyshekov, A.A.; Khapachev, Yu.P.

    1997-01-01

    It is proposed to use qualitative investigation methods of the differential Takagi equation solutions for the analysis of general properties of wave fields in deformed crystals. The physical interpretation of possible types of the Takagi equation solutions is considered briefly from the viewpoint of the stability theory. The type of solutions are defined by ratios between parameters involved in the equations set. For the Takagi equation these parameters are prescribed by the angular tuning from the precise Bragg angle as well as structural characteristics of the crystal and the deformation profile. The qualitative analysis for the problem of the dynamic X-ray diffraction is carried out for films with the variable deformation gradient and superlattices [ru

  5. S tudies on the phase transitions and properties of tungsten (VI oxide nanoparticles by X - Ray diffraction (XRD and thermal analysis

    Directory of Open Access Journals (Sweden)

    S.F. Abdullah

    2017-11-01

    Full Text Available Tungsten (VI oxide, WO3nanoparticles were synthesized by colloidal gas aphrons(CGAs technique.The resultant WO3nanoparticleswere characterized by thermogravimetric-differential thermal analysis (TG-DTA and X-Ray diffraction (XRD measurements in order to determine the phase transitions, the crystallinity and the size of theWO3nanoparticles. As a comparison, transmission electron microscope (TEM was used to investigate the size of the WO3nanoparticles. The result from XRD and DTA show that the formation of polymorphsWO3nanoparticles have the following sequence: orthorhombic (b-WO3®monoclinic (g-WO3 ®triclinic (d-WO3 ®monoclinic (e-WO3 with respect to the calcination temperature of 400, 500, 600 and 700°C. No diffraction peaks were found in the X-Ray diffraction measurements for the sample heat treated at 300°C (as-prepared, suggesting that an amorphous structure was obtained at this temperature whereas the crystallinity had been obtained by the other samples of theWO3nanoparticles at the calcination temperatures of 400, 500, 600 and 700°C. It is also found that the X-Ray diffraction measurements produced an average diameter of (30 ±5, (50 ±5, (150 ±10 and (200 ±10 nm at calcination temperatures of 400, 500, 600 and 700°C respectively by using Debye-Scherrer formula. The TG curve revealed that the WO3nanoparticles is purely anhydrous since the weight loss is insignificant (0.3 –1.4 % from 30 until 600°C for the WO3nanoparticles calcined at 400°C. Finally, the composition and the purity of the WO3nanoparticleshave been examined by X-Ray photoelectron spectroscopy (XPS. Theresults indicate no significant changes to the composition and the purity of the WO3nanoparticle produced due to the temperature variations

  6. Expression, purification, crystallization and preliminary X-ray diffraction analysis of dihydrodipicolinate synthase from Bacillus anthracis in the presence of pyruvate

    International Nuclear Information System (INIS)

    Voss, Jarrod E.; Scally, Stephen W.; Taylor, Nicole L.; Dogovski, Con; Alderton, Malcolm R.; Hutton, Craig A.; Gerrard, Juliet A.; Parker, Michael W.; Dobson, Renwick C. J.; Perugini, Matthew A.

    2009-01-01

    Dihydrodipicolinate synthase (DHDPS) catalyses an important step in lysine biosynthesis. Here, the expression, purification, crystallization and preliminary diffraction analysis to 2.15 Å resolution of DHDPS from B. anthracis soaked with the substrate pyruvate are reported. Dihydrodipicolinate synthase (DHDPS) catalyses the first committed step in the lysine-biosynthesis pathway in bacteria, plants and some fungi. In this study, the expression of DHDPS from Bacillus anthracis (Ba-DHDPS) and the purification of the recombinant enzyme in the absence and presence of the substrate pyruvate are described. It is shown that DHDPS from B. anthracis purified in the presence of pyruvate yields greater amounts of recombinant enzyme with more than 20-fold greater specific activity compared with the enzyme purified in the absence of substrate. It was therefore sought to crystallize Ba-DHDPS in the presence of the substrate. Pyruvate was soaked into crystals of Ba-DHDPS prepared in 0.2 M sodium fluoride, 20%(w/v) PEG 3350 and 0.1 M bis-tris propane pH 8.0. Preliminary X-ray diffraction data of the recombinant enzyme soaked with pyruvate at a resolution of 2.15 Å are presented. The pending crystal structure of the pyruvate-bound form of Ba-DHDPS will provide insight into the function and stability of this essential bacterial enzyme

  7. Human tRNAGly acceptor-stem microhelix: crystallization and preliminary X-ray diffraction analysis at 1.2 Å resolution

    International Nuclear Information System (INIS)

    Förster, Charlotte; Szkaradkiewicz, Karol; Perbandt, Markus; Brauer, Arnd B. E.; Borowski, Tordis; Fürste, Jens P.; Betzel, Christian; Erdmann, Volker A.

    2007-01-01

    The human tRNA Gly acceptor-stem microhelix was crystallized and preliminary X-ray diffraction analysis revealed diffraction to a resolution of up to 1.2 Å. The major dissimilarities between the eukaryotic/archaebacterial-type and eubacterial-type glycyl-tRNA synthetase systems (GlyRS; class II aminoacyl-tRNA synthetases) represent an intriguing example of evolutionarily divergent solutions to similar biological functions. The differences in the identity elements of the respective tRNA Gly systems are located within the acceptor stem and include the discriminator base U73. In the present work, the human tRNA Gly acceptor-stem microhelix was crystallized in an attempt to analyze the structural features that govern the correct recognition of tRNA Gly by the eukaryotic/archaebacterial-type glycyl-tRNA synthetase. The crystals of the human tRNA Gly acceptor-stem helix belong to the monoclinic space group C2, with unit-cell parameters a = 37.12, b = 37.49, c = 30.38 Å, α = γ = 90, β = 113.02°, and contain one molecule per asymmetric unit. A high-resolution data set was acquired using synchrotron radiation and the data were processed to 1.2 Å resolution

  8. Crystallization and preliminary X-ray diffraction analysis of a Lys49-phospholipase A2 complexed with caffeic acid, a molecule with inhibitory properties against snake venoms

    International Nuclear Information System (INIS)

    Shimabuku, Patrícia S.; Fernandes, Carlos A. H.; Magro, Angelo J.; Costa, Tássia R.; Soares, Andreimar M.; Fontes, Marcos R. M.

    2011-01-01

    Piratoxin I, a noncatalytic and myotoxic Lys49-phospholipase A 2 from B. pirajai venom, was cocrystallized with the inhibitor caffeic acid and a data set was collected to a resolution of 1.65 Å. The electron-density map unambiguously indicated that three inhibitor molecules interact with the C-terminus of the protein. Phospholipases A 2 (PLA 2 s) are one of the main components of bothropic venoms; in addition to their phospholipid hydrolysis action, they are involved in a wide spectrum of pharmacological activities, including neurotoxicity, myotoxicity and cardiotoxicity. Caffeic acid is an inhibitor that is present in several plants and is employed for the treatment of ophidian envenomations in the folk medicine of many developing countries; as bothropic snake bites are not efficiently neutralized by conventional serum therapy, it may be useful as an antivenom. In this work, the cocrystallization and preliminary X-ray diffraction analysis of the Lys49-PLA 2 piratoxin I from Bothrops pirajai venom in the presence of the inhibitor caffeic acid (CA) are reported. The crystals diffracted X-rays to 1.65 Å resolution and the structure was solved by molecular-replacement techniques. The electron-density map unambiguously indicated the presence of three CA molecules that interact with the C-terminus of the protein. This is the first time a ligand has been observed bound to this region and is in agreement with various experiments previously reported in the literature

  9. Crystallization and preliminary X-ray diffraction analysis of the C-terminal domain of the human spliceosomal DExD/H-box protein hPrp22

    International Nuclear Information System (INIS)

    Kudlinzki, Denis; Nagel, Christian; Ficner, Ralf

    2009-01-01

    The cloning, purification and crystallization of the C-terminal domain of human hPrp22 are reported. This communication also contains data for the preliminary X-ray diffraction analysis. The Homo sapiens DExD/H-box protein hPrp22 is a crucial component of the eukaryotic pre-mRNA splicing machinery. Within the splicing cycle, it is involved in the ligation of exons and generation of the lariat and it additionally catalyzes the release of mature mRNA from the spliceosomal U5 snRNP. The yeast homologue of this protein, yPrp22, shows ATP-dependent RNA-helicase activity and is capable of unwinding RNA/RNA duplex molecules. A truncated construct coding for residues 950–1183 of human Prp22, comprising the structurally and functionally uncharacterized C-terminal domain, was cloned into an Escherichia coli expression vector. The protein was subsequently overproduced, purified and crystallized. The crystals obtained diffracted to 2.1 Å resolution, belonged to the tetragonal space group P4 1 2 1 2 or P4 3 2 1 2, with unit-cell parameters a = b = 78.2, c = 88.4 Å, and contained one molecule in the asymmetric unit

  10. Towards diffractive imaging with single pulses of FEL radiation. Dynamics within irradiatied samples and their influence on the analysis of imaging data

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Fenglin

    2010-08-15

    3D single particle coherent diffraction imaging (CDI) of bioparticles (such as proteins, macromolecules and viruses) is one of the main possible applications of the new generation of light sources: free-electron lasers (FELs), which are now available at FLASH (Hamburg, Germany) and LCLS (Stanford, U.S.A.). The extremely bright and ultrashort FEL pulses potentially enable CDI to achieve high resolution down to subnanometer length scale. However, intense FEL pulses cause serious radiation damage in bioparticles, even during single shots, which may set the resolution limits for CDI with FELs. Currently, since the signal-to-noise ratio is very low for small biological particles, direct experimental study of radiation damage in the single particle imaging is fairly difficult. Single atomic (noble gas) clusters become good objects to reveal effects of radiation damage processes on CDI with FEL radiation. This thesis studies three aspects of the radiation damage problem, which are treated in three independent chapters: (1) Molecular Dynamics simulations to quantitively describe radiation damage processes within irradiated atomic clusters during single pulses; (2) reconstruction analysis of single-shot CDI diffraction patterns of atomic clusters, which may potentially help to understand the radiation damage occurring in biological samples; and (3) testing the effects of coating water layers in CDI, which is supposed to minimize the radiation damage in irradiated bioparticles. (orig.)

  11. Crystallization and preliminary X-ray diffraction analysis of mouse galectin-4 N-terminal carbohydrate recognition domain in complex with lactose

    International Nuclear Information System (INIS)

    Krejčiříková, Veronika; Fábry, Milan; Marková, Vladimíra; Malý, Petr; Řezáčová, Pavlína; Brynda, Jiří

    2008-01-01

    Mouse galectin-4 carbohydrate binding domain was overexpressed in E. coli and crystallized in the presence of lactose. The crystals belong to tetragonal space group P42 1 2 and diffraction data were collected to 2.1 Å resolution. Galectin-4 is thought to play a role in the process of tumour conversion of cells of the alimentary tract and the breast tissue; however, its exact function remains unknown. With the aim of elucidating the structural basis of mouse galectin-4 (mGal-4) binding specificity, we have undertaken X-ray analysis of the N-terminal domain, CRD1, of mGal-4 in complex with lactose (the basic building block of known galectin-4 carbohydrate ligands). Crystals of CRD1 in complex with lactose were obtained using vapour-diffusion techniques. The crystals belong to tetragonal space group P42 1 2 with unit-cell parameters a = 91.1, b = 91.16, c = 57.10 Å and preliminary X-ray diffraction data were collected to 3.2 Å resolution. An optimized crystallization procedure and cryocooling protocol allowed us to extend resolution to 2.1 Å. Structure refinement is currently under way; the initial electron-density maps clearly show non-protein electron density in the vicinity of the carbohydrate binding site, indicating the presence of one lactose molecule. The structure will help to improve understanding of the binding specificity and function of the potential colon cancer marker galectin-4

  12. Purification, crystallization and preliminary X-ray diffraction analysis of an acidic phospholipase A2 with vasoconstrictor activity from Agkistrodon halys pallas venom

    International Nuclear Information System (INIS)

    Zou, Zhisong; Zeng, Fuxing; Zhang, Lu; Niu, Liwen; Teng, Maikun; Li, Xu

    2012-01-01

    A vasoconstrictor PLA 2 was purified from Agkistrodon halys pallas venom and the preliminary X-ray diffraction analysis had been described. Phospholipases A 2 (PLA 2 s) are the major component of snake venoms and exert a variety of relevant toxic actions such as neurotoxicity and myotoxicity, amongst others. An acidic PLA 2 , here named AhV-aPA, was purified from Agkistrodon halys pallas venom by means of a three-step chromatographic procedure. AhV-aPA migrated as a single band on SDS–PAGE gels, with a molecular weight of about 14 kDa. Like other acidic aPLA 2 s, AhV-aPA has high enzymatic activity. Tension measurements of mouse thoracic aortic rings remarkably indicated that AhV-aPA could induce a further contractile response on the 60 mM K + -induced contraction, with an EC 50 of 369 nmol l −1 . Rod-shaped crystals were obtained by the hanging-drop vapour-diffusion method and diffracted to a resolution limit of 2.30 Å. The crystals belonged to space group P222, with unit-cell parameters a = 44.27, b = 68.39, c = 81.54 Å

  13. Expression, crystallization and preliminary X-ray diffraction analysis of the CMM2 region of the Arabidopsis thaliana Morpheus’ molecule 1 protein

    International Nuclear Information System (INIS)

    Petty, Tom J.; Nishimura, Taisuke; Emamzadah, Soheila; Gabus, Caroline; Paszkowski, Jerzy; Halazonetis, Thanos D.; Thore, Stéphane

    2010-01-01

    In order to investigate its function in transcriptional gene silencing, the highly conserved motif 2 from A. thaliana Morpheus’ molecule 1 protein was expressed, purified and crystallized. X-ray diffraction analysis is reported to a resolution of 3.2 Å. Of the known epigenetic control regulators found in plants, the Morpheus’ molecule 1 (MOM1) protein is atypical in that the deletion of MOM1 does not affect the level of epigenetic marks controlling the transcriptional status of the genome. A short 197-amino-acid fragment of the MOM1 protein sequence can complement MOM1 deletion when coupled to a nuclear localization signal, suggesting that this region contains a functional domain that compensates for the loss of the full-length protein. Numerous constructs centred on the highly conserved MOM1 motif 2 (CMM2) present in these 197 residues have been generated and expressed in Escherichia coli. Following purification and crystallization screening, diamond-shaped single crystals were obtained that diffracted to ∼3.2 Å resolution. They belonged to the trigonal space group P3 1 21 (or P3 2 21), with unit-cell parameters a = 85.64, c = 292.74 Å. Structure determination is ongoing

  14. Microstructural analysis in the depth direction of a heteroepitaxial AlN thick film grown on a trench-patterned template by nanobeam X-ray diffraction

    Science.gov (United States)

    Shida, K.; Takeuchi, S.; Tohei, T.; Miyake, H.; Hiramatsu, K.; Sumitani, K.; Imai, Y.; Kimura, S.; Sakai, A.

    2018-04-01

    This work quantitatively assessed the three-dimensional distribution of crystal lattice distortions in an epitaxial AlN thick film grown on a trench-patterned template, using nanobeam X-ray diffraction. Position-dependent ω-2θ-φ mapping clearly demonstrated local tilting, spacing and twisting of lattice planes as well as fluctuations in these phenomena on a sub-micrometer scale comparable to the pitch of the trench-and-terrace patterning. Analysis of the crystal lattice distortion in the depth direction was performed using a newly developed method in which the X-ray nanobeam diffracted from the sample surface to specific depths can be selectively detected by employing a Pt wire profiler. This technique generated depth-resolved ω-2θ-φ maps confirming that fluctuations in lattice plane tilting and spacing greatly depend on the dislocation distribution and the history of the AlN epitaxial growth on the trench-patterned structure. It was also found that both fluctuations were reduced on approaching the AlN surface and, in particular, were sharply reduced at specific depths in the terrace regions. These sharp reductions are attributed to the formation of sacrificial zones with degraded crystal quality around the trenches and possibly lead to raising the crystal quality near the surface of the AlN film.

  15. Crystallization and preliminary X-ray diffraction analysis of two extracytoplasmic solute receptors of the DctP family from Bordetella pertussis

    International Nuclear Information System (INIS)

    Rucktooa, Prakash; Huvent, Isabelle; Antoine, Rudy; Lecher, Sophie; Jacob-Dubuisson, Françoise; Villeret, Vincent; Bompard, Coralie

    2006-01-01

    Sample preparation, crystallization and preliminary X-ray analysis are reported for two B. pertussis extracytoplasmic solute receptors. DctP6 and DctP7 are two Bordetella pertussis proteins which belong to the extracytoplasmic solute receptors (ESR) superfamily. ESRs are involved in the transport of substrates from the periplasm to the cytosol of Gram-negative bacteria. DctP6 and DctP7 have been crystallized and diffraction data were collected using a synchrotron-radiation source. DctP6 crystallized in space group P4 1 2 1 2, with unit-cell parameters a = 108.39, b = 108.39, c = 63.09 Å, while selenomethionyl-derivatized DctP7 crystallized in space group P2 1 2 1 2 1 , with unit-cell parameters a = 64.87, b = 149.83, c = 170.65 Å. The three-dimensional structure of DctP7 will be determined by single-wavelength anomalous diffraction, while the DctP6 structure will be solved by molecular-replacement methods

  16. Crystallization and preliminary X-ray diffraction analysis of two extracytoplasmic solute receptors of the DctP family from Bordetella pertussis

    Energy Technology Data Exchange (ETDEWEB)

    Rucktooa, Prakash; Huvent, Isabelle [UMR8161 CNRS Institut de Biologie de Lille, Laboratoire de Cristallographie Macromoléculaire, 1 Rue du Professeur Calmette, BP 447, 59021 Lille CEDEX (France); IFR 142, Institut Pasteur de Lille, 1 Rue du Professeur Calmette, BP 245, 59021 Lille CEDEX (France); Antoine, Rudy; Lecher, Sophie; Jacob-Dubuisson, Françoise, E-mail: francoise.jacob@ibl.fr [IFR 142, Institut Pasteur de Lille, 1 Rue du Professeur Calmette, BP 245, 59021 Lille CEDEX (France); INSERM-U629, Lille (France); Institut Pasteur de Lille, 1 Rue du Professeur Calmette, BP 245, 59021 Lille CEDEX (France); Villeret, Vincent, E-mail: francoise.jacob@ibl.fr; Bompard, Coralie [UMR8161 CNRS Institut de Biologie de Lille, Laboratoire de Cristallographie Macromoléculaire, 1 Rue du Professeur Calmette, BP 447, 59021 Lille CEDEX (France); IFR 142, Institut Pasteur de Lille, 1 Rue du Professeur Calmette, BP 245, 59021 Lille CEDEX (France)

    2006-10-01

    Sample preparation, crystallization and preliminary X-ray analysis are reported for two B. pertussis extracytoplasmic solute receptors. DctP6 and DctP7 are two Bordetella pertussis proteins which belong to the extracytoplasmic solute receptors (ESR) superfamily. ESRs are involved in the transport of substrates from the periplasm to the cytosol of Gram-negative bacteria. DctP6 and DctP7 have been crystallized and diffraction data were collected using a synchrotron-radiation source. DctP6 crystallized in space group P4{sub 1}2{sub 1}2, with unit-cell parameters a = 108.39, b = 108.39, c = 63.09 Å, while selenomethionyl-derivatized DctP7 crystallized in space group P2{sub 1}2{sub 1}2{sub 1}, with unit-cell parameters a = 64.87, b = 149.83, c = 170.65 Å. The three-dimensional structure of DctP7 will be determined by single-wavelength anomalous diffraction, while the DctP6 structure will be solved by molecular-replacement methods.

  17. Purification, crystallization, small-angle X-ray scattering and preliminary X-ray diffraction analysis of the SH2 domain of the Csk-homologous kinase

    International Nuclear Information System (INIS)

    Gunn, Natalie J.; Gorman, Michael A.; Dobson, Renwick C. J.; Parker, Michael W.; Mulhern, Terrence D.

    2011-01-01

    The Src-homology 2 (SH2) domain of Csk-family protein tyrosine kinases acts as a conformational switch to regulate their catalytic activity, which in turn promotes the inhibition of their proto-oncogenic targets, the Src-family kinases. Here, the expression, purification, small-angle X-ray scattering and preliminary diffraction analysis of the SH2 domain of the Csk-homologous kinase is reported. The C-terminal Src kinase (Csk) and Csk-homologous kinase (CHK) are endogenous inhibitors of the proto-oncogenic Src family of protein tyrosine kinases (SFKs). Phosphotyrosyl peptide binding to their Src-homology 2 (SH2) domains activates Csk and CHK, enhancing their ability to suppress SFK signalling; however, the detailed mechanistic basis of this activation event is unclear. The CHK SH2 was expressed in Escherichia coli and the purified protein was characterized as monomeric by synchrotron small-angle X-ray scattering in-line with size-exclusion chromatography. The CHK SH2 crystallized in 0.2 M sodium bromide, 0.1 M bis-Tris propane pH 6.5 and 20% polyethylene glycol 3350 and the best crystals diffracted to ∼1.6 Å resolution. The crystals belonged to space group P2, with unit-cell parameters a = 25.8, b = 34.6, c = 63.2 Å, β = 99.4°

  18. Purification, crystallization and X-ray diffraction analysis of a novel ring-cleaving enzyme (BoxCC) from Burkholderia xenovorans LB400

    International Nuclear Information System (INIS)

    Bains, Jasleen; Boulanger, Martin J.

    2008-01-01

    Preliminary X-ray diffraction studies of a novel ring-cleaving enzyme from B. xenovorans LB400 encoded by the benzoate-oxidation (box) pathway. The assimilation of aromatic compounds by microbial species requires specialized enzymes to cleave the thermodynamically stable ring. In the recently discovered benzoate-oxidation (box) pathway in Burkholderia xenovorans LB400, this is accomplished by a novel dihydrodiol lyase (BoxC C ). Sequence analysis suggests that BoxC C is part of the crotonase superfamily but includes an additional uncharacterized region of approximately 115 residues that is predicted to mediate ring cleavage. Processing of X-ray diffraction data to 1.5 Å resolution revealed that BoxC C crystallized with two molecules in the asymmetric unit of the P2 1 2 1 2 1 space group, with a solvent content of 47% and a Matthews coefficient of 2.32 Å 3 Da −1 . Selenomethionine BoxC C has been purified and crystals are currently being refined for anomalous dispersion studies

  19. Observables of QCD diffraction

    Science.gov (United States)

    Mieskolainen, Mikael; Orava, Risto

    2017-03-01

    A new combinatorial vector space measurement model is introduced for soft QCD diffraction. The model independent mathematical construction resolves experimental complications; the theoretical framework of the approach includes the Good-Walker view of diffraction, Regge phenomenology together with AGK cutting rules and random fluctuations.

  20. Texture Analysis using The Neutron Diffraction Method on The Non Standardized Austenitic Steel Process by Machining,Annealing, and Rolling

    Directory of Open Access Journals (Sweden)

    Tri Hardi Priyanto

    2016-04-01

    Full Text Available Austenitic steel is one type of stainless steel which is widely used in the industry. Many studies on  austenitic stainless steel have been performed to determine the physicalproperties using various types of equipment and methods. In this study, the neutron diffraction method is used to characterize the materials which have been made from  minerals extracted from the mines in Indonesia. The materials consist of a granular ferro-scrap, nickel, ferro-chrome, ferro-manganese, and ferro-silicon added with a little titanium. Characterization of the materials was carried out in threeprocesses, namely: machining, annealing, and rolling. Experimental results obtained from the machining process generally produces a texture in the 〈100〉direction. From the machining to annealing process, the texture index decreases from 3.0164 to 2.434.Texture strength in the machining process (BA2N sample is  8.13 mrd and it then decreases to 6.99 in the annealing process (A2DO sample. In the annealing process the three-component texture appears, cube-on-edge type texture{110}〈001〉, cube-type texture {001}〈100〉, and brass-type {110}〈112〉. The texture is very strong leading to the direction of orientation {100}〈001〉, while the {011}〈100〉is weaker than that of the {001}, and texture withorientation {110}〈112〉is weak. In the annealing process stress release occurred, and this was shown by more randomly pole compared to stress release by the machining process. In the rolling process a brass-type texture{110}〈112〉with a spread towards the goss-type texture {110}〈001〉 appeared,  and  the  brass  component  is markedly  reinforced  compared  to  the undeformed state (before rolling. Moreover, the presence of an additional {110} component was observed at the center of the (110 pole figure. The pole density of three components increases withthe increasing degree of thickness reduction. By increasing degrees

  1. Purification, crystallization and preliminary X-ray diffraction analysis of the Escherichia coli common pilus chaperone EcpB

    Energy Technology Data Exchange (ETDEWEB)

    Garnett, James A.; Diallo, Mamou; Matthews, Steve J., E-mail: s.j.matthews@imperial.ac.uk [Imperial College London, South Kensington, London SW7 2AZ (United Kingdom)

    2015-05-20

    In Escherichia coli, the common pilus (Ecp) belongs to an alternative chaperone–usher pathway that plays a major role in both early biofilm formation and host-cell adhesion. Initial attempts at crystallizing the chaperone EcpB using natively purified protein from the bacterial periplasm were not successful; however, after the isolation of EcpB under denaturing conditions and subsequent refolding, crystals were obtained at pH 8.0 using the sitting-drop method of vapour diffusion. This is the first time that this refolding strategy has been used to purify CU chaperones. Pili are key cell-surface components that allow the attachment of bacteria to both biological and abiotic solid surfaces, whilst also mediating interactions between themselves. In Escherichia coli, the common pilus (Ecp) belongs to an alternative chaperone–usher (CU) pathway that plays a major role in both early biofilm formation and host-cell adhesion. The chaperone EcpB is involved in the biogenesis of the filament, which is composed of EcpA and EcpD. Initial attempts at crystallizing EcpB using natively purified protein from the bacterial periplasm were not successful; however, after the isolation of EcpB under denaturing conditions and subsequent refolding, crystals were obtained at pH 8.0 using the sitting-drop method of vapour diffusion. Diffraction data have been processed to 2.4 Å resolution. These crystals belonged to the trigonal space group P3{sub 1}21 or P3{sub 2}21, with unit-cell parameters a = b = 62.65, c = 121.14 Å and one monomer in the asymmetric unit. Molecular replacement was unsuccessful, but selenomethionine-substituted protein and heavy-atom derivatives are being prepared for phasing. The three-dimensional structure of EcpB will provide invaluable information on the subtle mechanistic differences in biogenesis between the alternative and classical CU pathways. Furthermore, this is the first time that this refolding strategy has been used to purify CU chaperones, and it

  2. Purification, crystallization and preliminary X-ray diffraction analysis of the Escherichia coli common pilus chaperone EcpB

    International Nuclear Information System (INIS)

    Garnett, James A.; Diallo, Mamou; Matthews, Steve J.

    2015-01-01

    In Escherichia coli, the common pilus (Ecp) belongs to an alternative chaperone–usher pathway that plays a major role in both early biofilm formation and host-cell adhesion. Initial attempts at crystallizing the chaperone EcpB using natively purified protein from the bacterial periplasm were not successful; however, after the isolation of EcpB under denaturing conditions and subsequent refolding, crystals were obtained at pH 8.0 using the sitting-drop method of vapour diffusion. This is the first time that this refolding strategy has been used to purify CU chaperones. Pili are key cell-surface components that allow the attachment of bacteria to both biological and abiotic solid surfaces, whilst also mediating interactions between themselves. In Escherichia coli, the common pilus (Ecp) belongs to an alternative chaperone–usher (CU) pathway that plays a major role in both early biofilm formation and host-cell adhesion. The chaperone EcpB is involved in the biogenesis of the filament, which is composed of EcpA and EcpD. Initial attempts at crystallizing EcpB using natively purified protein from the bacterial periplasm were not successful; however, after the isolation of EcpB under denaturing conditions and subsequent refolding, crystals were obtained at pH 8.0 using the sitting-drop method of vapour diffusion. Diffraction data have been processed to 2.4 Å resolution. These crystals belonged to the trigonal space group P3 1 21 or P3 2 21, with unit-cell parameters a = b = 62.65, c = 121.14 Å and one monomer in the asymmetric unit. Molecular replacement was unsuccessful, but selenomethionine-substituted protein and heavy-atom derivatives are being prepared for phasing. The three-dimensional structure of EcpB will provide invaluable information on the subtle mechanistic differences in biogenesis between the alternative and classical CU pathways. Furthermore, this is the first time that this refolding strategy has been used to purify CU chaperones, and it could be

  3. In Situ Study of Microstructure Evolution in Solidification of Hypereutectic Al-Si Alloys with Application of Thermal Analysis and Neutron Diffraction

    Science.gov (United States)

    Sediako, Dimitry G.; Kasprzak, Wojciech

    2015-09-01

    Understanding of the kinetics of solid-phase evolution in solidification of hypereutectic aluminum alloys is a key to control their as-cast microstructure and resultant mechanical properties, and in turn, to enhance the service characteristics of actual components. This study was performed to evaluate the solidification kinetics for three P-modified hypereutectic Al-19 pct Si alloys: namely, Al-Si binary alloy and with the subsequent addition of 2.8 pct Cu and 2.8 pct Cu + 0.7 pct Mg. Metallurgical evaluation included thermodynamic calculations of the solidification process using the FactSage™ 6.2 software package, as well as experimental thermal analysis, and in situ neutron diffraction. The study revealed kinetics of solid α-Al, solid Si, Al2Cu, and Mg2Si evolution, as well as the individual effects of Cu and Mg alloying additions on the solidification path of the Al-Si system. Various techniques applied in this study resulted in some discrepancies in the results. For example, the FactSage computations, in general, resulted in 281 K to 286 K (8 °C to 13 °C) higher Al-Si eutectic temperatures than the ones recorded in the thermal analysis, which are also ~278 K (~5 °C) higher than those observed in the in situ neutron diffraction. None of the techniques can provide a definite value for the solidus temperature, as this is affected by the chosen calculation path [283 K to 303 K (10 °C to 30 °C) higher for equilibrium solidification vs non-equilibrium] for the FactSage analysis; and further complicated by evolution of secondary Al-Cu and Mg-Si phases that commenced at the end of solidification. An explanation of the discrepancies observed and complications associated with every technique applied is offered in the paper.

  4. Cloning, purification, crystallization and preliminary X-ray diffraction analysis of nitrile hydratase from the themophilic Bacillus smithii SC-J05-1

    International Nuclear Information System (INIS)

    Hourai, Shinji; Ishii, Takeshi; Miki, Misao; Takashima, Yoshiki; Mitsuda, Satoshi; Yanagi, Kazunori

    2005-01-01

    The nitrile hydratase from the themophilic B. smithii SC-J05-1 (Bs NHase) has been purified, cloned and crystallized. Nitrile hydratase (NHase) converts nitriles to the corresponding amides and is recognized as having important industrial applications. Purification, cloning, crystallization and initial crystallographic studies of the NHase from Bacillus smithii SC-J05-1 (Bs NHase) were conducted to analyze the activity, specificity and thermal stability of this hydrolytic enzyme. Bs NHase was purified to homogeneity from microbial cells of B. smithii SC-J05-1 and the nucleotide sequences of both the α- and β-subunits were determined. Purified Bs NHase was used for crystallization and several crystal forms were obtained by the vapour-diffusion method. Microseeding and the addition of magnesium ions were essential components to obtain crystals suitable for X-ray diffraction analysis

  5. X-ray diffraction analysis of KY3F10 nanoparticles doped with Nd and preliminary studies for its use in high-dose radiation dosimetry

    International Nuclear Information System (INIS)

    Ichikawa, Rodrigo U.; Linhares, Horacio M.S.M.D.; Silva, Andre S.B. da; Teixeira, Maria I.; Ranieri, Izilda M.; Turrillas, Xavier; Martinez, G.

    2017-01-01

    In this work, the structure and microstructure of Nd:KY 3 F 10 nanoparticles was probed using X-ray synchrotron diffraction analysis. Rietveld refinement was applied to obtain cell parameters, atomic positions and atomic displacement factors to be compared with the ones found in literature. X-ray line profile methods were applied to determine mean crystallite size and crystallite size distribution. Thermoluminescent (TL) emission curves were measured for different radiation doses, from 0.10kGy up to 10.0kGy. Dose-response curves were obtained by area integration beneath the peaks from TL. The reproducibility of the results in this work has shown that this material can be considered a good dosimetric material. (author)

  6. X-ray diffraction analysis of KY3F10 nanoparticles doped with Nd and preliminary studies for its use in high-dose radiation dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Ichikawa, Rodrigo U.; Linhares, Horacio M.S.M.D.; Silva, Andre S.B. da; Teixeira, Maria I.; Ranieri, Izilda M.; Turrillas, Xavier; Martinez, G., E-mail: ichikawa@usp.br, E-mail: andre.santos.silva@usp.br, E-mail: miteixeira@ipen.br, E-mail: iranieri@ipen.br, E-mail: lgallego@ipen.br, E-mail: horaciolinhares@id.uff.br, E-mail: xturrillas@icmab.es [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Universidade Federal Fluminense (INFES/ UFF), Niteroi, RJ (Brazil); Institut de Ciència de Materials de Barcelona (ICMAB / CSIC) (Spain)

    2017-07-01

    In this work, the structure and microstructure of Nd:KY{sub 3}F{sub 10} nanoparticles was probed using X-ray synchrotron diffraction analysis. Rietveld refinement was applied to obtain cell parameters, atomic positions and atomic displacement factors to be compared with the ones found in literature. X-ray line profile methods were applied to determine mean crystallite size and crystallite size distribution. Thermoluminescent (TL) emission curves were measured for different radiation doses, from 0.10kGy up to 10.0kGy. Dose-response curves were obtained by area integration beneath the peaks from TL. The reproducibility of the results in this work has shown that this material can be considered a good dosimetric material. (author)

  7. Borehole radar diffraction tomography

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Seong Jun; Kim, Jung Ho; Yi, Myeong Jong; Chung, Seung Hwan; Lee, Hee Il [Korea Institute of Geology Mining and Materials, Taejon (Korea, Republic of)

    1997-12-01

    Tomography is widely used as imaging method for determining subsurface structure. Among the reconstruction algorithms for tomographic imaging, travel time tomography is almost applied to imaging subsurface. But isolated small body comparable with the wavelength could not be well recognized by travel time tomography. Other tomographic method are need to improve the imaging process. In the study of this year, diffraction tomography was investigated. The theory for diffraction tomography is based on the 1st-order Born approximation. Multisource holography, which is similar to Kirchihoff migration, is compared with diffraction tomography. To improve 1st-order Born diffraction tomography, two kinds of filter designed from multisource holography and 2-D green function, respectively, applied on the reconstructed image. The algorithm was tested for the numerical modeling data of which algorithm consists of the analytic computation of radar signal in transmitter and receiver regions and 2-D FDM scheme for the propagation of electromagnetic waves in media. The air-filled cavity model to show a typical diffraction pattern was applied to diffraction tomography imaging, and the result shows accurate location and area of cavity. But the calculated object function is not well matched the real object function, because the air-filled cavity model is not satisfied week scattered inhomogeneity for 1st born approximation, and the error term is included in estimating source wavelet from received signals. In spite of the object function error, the diffraction tomography assist for interpretation of subsurface as if conducted with travel time tomography. And the fracture model was tested, 1st born diffraction tomographic image is poor because of limited view angle coverage and violation of week scatter assumption, but the filtered image resolve the fracture somewhat better. The tested diffraction tomography image confirms effectiveness of filter for enhancing resolution. (author). 14

  8. Non-diffractive waves

    CERN Document Server

    Hernandez-Figueroa, Hugo E; Recami, Erasmo

    2013-01-01

    This continuation and extension of the successful book ""Localized Waves"" by the same editors brings together leading researchers in non-diffractive waves to cover the most important results in their field and as such is the first to present the current state.The well-balanced presentation of theory and experiments guides readers through the background of different types of non-diffractive waves, their generation, propagation, and possible applications. The authors include a historical account of the development of the field, and cover different types of non-diffractive waves, including Airy

  9. Identification of intermetallic phases in a eutectic Al-Si casting alloy using electron backscatter diffraction pattern analysis

    International Nuclear Information System (INIS)

    Kral, M.V.; McIntyre, H.R.; Smillie, M.J.

    2004-01-01

    Intermetallic phases in sand cast eutectic Al-Si alloys were characterized using a combination of SEM, EDS and EBSD pattern analysis. Chinese script α-phase particles were consistent with cubic Al 19 (Fe,Mn) 5 Si 2 . Plate-shaped β-phase particles were consistent with tetragonal Al 3 (Fe,Mn)Si 2

  10. First use of portable system coupling X-ray diffraction and X-ray fluorescence for in-situ analysis of prehistoric rock art.

    Science.gov (United States)

    Beck, L; Rousselière, H; Castaing, J; Duran, A; Lebon, M; Moignard, B; Plassard, F

    2014-11-01

    Study of prehistoric art is playing a major role in the knowledge of human evolution. Many scientific methods are involved in this investigation including chemical analysis of pigments present on artefacts or applied to cave walls. In the past decades, the characterization of coloured materials was carried on by taking small samples. This procedure had two main disadvantages: slight but existing damage of the paintings and limitation of the number of samples. Thanks to the advanced development of portable systems, in-situ analysis of pigment in cave can be now undertaken without fear for this fragile Cultural Heritage. For the first time, a portable system combining XRD and XRF was used in an underground and archaeological environment for prehistoric rock art studies. In-situ non-destructive analysis of black prehistoric drawings and determination of their composition and crystalline structure were successfully carried out. Original results on pigments used 13,000 years ago in the cave of Rouffignac (France) were obtained showing the use of two main manganese oxides: pyrolusite and romanechite. The capabilities of the portable XRD-XRF system have been demonstrated for the characterization of pigments as well as for the analysis of rock in a cave environment. This first in-situ experiment combining X-ray diffraction and X-ray fluorescence open up new horizons and can fundamentally change our approach of rock art studies. Copyright © 2014 Elsevier B.V. All rights reserved.

  11. Causal aspects of diffraction

    International Nuclear Information System (INIS)

    Crawford, G.N.

    1981-01-01

    The analysis is directed at a causal description of photon diffraction, which is explained in terms of a wave exerting real forces and providing actual guidance to each quantum of energy. An undulatory PSI wave is associated with each photon, and this wave is assumed to imply more than an informative probability function, so that it actually carries real energy, in much the same way as does an electro-magnetic wave. Whether or not it may be in some way related to the electromagnetic wave is left as a matter of on-going concern. A novel application of the concept of a minimum energy configuration is utilized; that is, a system of energy quanta seeks out relative positions and orientations of least mutual energy, much as an electron seeks its Bohr radius as a position of least mutual energy. Thus the concept implies more a guiding interaction of the PSI waves than an interfering cancellation of these waves. Similar concepts have been suggested by L. de Broglie and D. Bohm

  12. Fast in situ X-ray diffraction phase and stress analysis during complete heat treatment cycles of steel

    International Nuclear Information System (INIS)

    Rocha, A. da S.; Hirsch, T.

    2005-01-01

    This paper presents results obtained with a method for time and temperature resolved analysis of changes in phase composition and stresses/residual stresses during complete heat treatment cycles of steel, including quenching. Sample temperatures of up to 930 deg. C could be reached with a specially designed furnace, where fast cooling of the samples was realized by gas quenching. Measurements for phase and stress analysis could be performed with an acquisition rate of at least one value every 3 s. Results concerning residual stress relaxation during heating, and stress/residual stress development during quenching are presented and discussed for AISI E52100 ball bearing steel. The observed stress development during quenching followed the expected transformation behavior with some deviations that could be explained through the effects of surface decarburization. The system developed proved to be a suitable tool for characterizing phase and stress changes that occur during heat treatment of steels, as a function of time and temperature

  13. Reflector imaging by diffraction stacking with stacking velocity analysis; Jugo sokudo kaiseki wo tomonau sanran jugoho ni yoru hanshamen imaging

    Energy Technology Data Exchange (ETDEWEB)

    Matsushima, J; Rokugawa, S; Kato, Y [The University of Tokyo, Tokyo (Japan). Faculty of Engineering; Yokota, T [Japan National Oil Corp., Tokyo (Japan); Miyazaki, T [Geological Survey of Japan, Tsukuba (Japan)

    1997-10-22

    Concerning seismic reflection survey for geometrical arrangement between pits, the scattering stacking method with stacking velocity analysis is compared with the CDP (common depth point horizontal stacking method). The advantages of the CDP supposedly include the following. Since it presumes an average velocity field, it can determine velocities having stacking effects. The method presumes stratification and, since such enables the division of huge quantities of observed data into smaller groups, more data can be calculated in a shorter time period. The method has disadvantages, attributable to its presuming an average velocity field, that accuracy in processing is lower when the velocity field contrast is higher, that accuracy in processing is low unless stratification is employed, and that velocities obtained from stacking velocity analysis are affected by dipped structures. Such shortcomings may be remedied in the scattering stacking method with stacking velocity analysis. Possibilities are that, as far as the horizontal reflection plane is concerned, it may yield stack records higher in S/N ratio than the CDP. Findings relative to dipped reflection planes will be introduced at the presentation. 6 refs., 12 figs.

  14. High energy diffraction

    International Nuclear Information System (INIS)

    Berger, C.

    1995-11-01

    Recent experiments on total hadronic cross sections are reviewed together with results on photo- and electroproduction of vector mesons. New data on diffractive deep inelastic scattering shed light on the nature of the pomeron. (orig.)

  15. Duality in diffraction dissociations

    International Nuclear Information System (INIS)

    Santoro, Alberto.

    1977-01-01

    Diffractive dissociations (aN→a*πN) are naturally explained and a model that accounts for the three-variable correlation (mass-transfer-Jackson angle correlation) is presented. This model takes into account the three possible exchanges: t (pion), u(a*) and s(a) channel exchanger. The physical consequences of the model are: a strong mass-slope correlation due to the zeros of the amplitude, a factorization of diffractive dissociations (factorization of the Pomeron), the possibility of extending this model to double diffractive dissociation and diffraction by nuclei. This model was applied to the NN→NπN reaction. Using the usual parameters of the Deck model, a comparison is made with experiments for all available distributions. the strong slope of the peak at 1400 MeV is naturally explained [fr

  16. DIFFRACTION SYNCHRONIZATION OF LASERS,

    Science.gov (United States)

    semiconductor lasers while suppressing parasitic generation in the plane of the mirror. The diffraction coupling coefficient of open resonators is calculated, and the stability conditions of the synchronized system is determined.

  17. High energy X-ray diffraction analysis of strain and residual stress in silicon nitride ceramic diffusion bonds

    International Nuclear Information System (INIS)

    Vila, M.; Prieto, C.; Miranzo, P.; Osendi, M.I.; Terry, A.E.; Vaughan, G.B.M.

    2005-01-01

    High resolution X-ray scanning diffractometry is used to study the residual stress in binary metal/ceramic (Ni/Si 3 N 4 ) diffusion bonds fabricated by simultaneous high temperature heating and uniaxial pressing. In order to diminish the experimental error on the stress determination, the method consists of three steps: (i) to measure the axial and radial strains following some selected lines at the inner volume of the ceramic; (ii) to fit the strain data using finite element method (FEM) analysis and (iii) to determinate stresses by using the results obtained from the FEM method in the strain calculation

  18. Crystallization and preliminary X-ray diffraction analysis of inositol 1,3,4,5,6-pentakisphosphate kinase from Arabidopsis thaliana

    International Nuclear Information System (INIS)

    Baños-Sanz, Jose Ignacio; Villate, Maider; Sanz-Aparicio, Julia; Brearley, Charles Alistair; González, Beatriz

    2009-01-01

    Inositol 1,3,4,5,6-pentakisphosphate kinase from A. thaliana has been expressed in E. coli, purified and crystallized and diffraction data have been collected to 2.3 Å resolution. Two heavy-atom crystal derivatives are under study. Inositol 1,3,4,5,6-pentakisphosphate kinase (IP 5 2-K) is an enzyme involved in inositol metabolism that synthesizes IP 6 (inositol 1,2,3,4,5,6-hexakisphosphate) from inositol 1,3,4,5,6-pentakisphosphate (IP 5 ) and ATP. IP 6 is the major phosphorus reserve in plants, while in mammals it is involved in multiple cellular events such as DNA editing and chromatin remodelling. In addition, IP 6 is the precursor of other highly phosphorylated inositols which also play highly relevant roles. IP 5 2-K is the only enzyme that phosphorylates the 2-OH axial position of the inositide and understanding its molecular mechanism of substrate specificity is of great interest in cell biology. IP 5 2-K from Arabidopsis thaliana has been expressed in Escherichia coli as two different fusion proteins and purified. Both protein preparations yielded crystals of different quality, always in the presence of IP 6 . The best crystals obtained for X-ray crystallographic analysis belonged to space group P2 1 2 1 2 1 , with unit-cell parameters a = 58.124, b = 113.591, c = 142.478 Å. Several diffraction data sets were collected for the native enzyme and two heavy-atom derivatives using a synchrotron source

  19. 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

  20. Operando X-ray diffraction analysis for a glyme-based Li-O{sub 2} battery

    Energy Technology Data Exchange (ETDEWEB)

    Yogi, C.; Takao, N.; Kubobuchi, K.; Matsumoto, M.; Mogi, M., E-mail: mogi@nissan-arc.co.jp; Imai, H. [Device-functional analysis department, NISSAN ARC Ltd., 1 Natsushima, Yokosuka Kanagawa, 237-0061 JAPAN (Japan); Watanabe, T. [Japan Synchrotron Radiation Research Institute (JASRI), 1-1-1 Koto, Sayo Hyogo, 679-5198 JAPAN (Japan)

    2016-08-26

    We investigated the effect of the carbon species in the air (oxygen) electrode, electrolyte concentration, and humidity in the supplied O{sub 2} gas on the Li-O{sub 2} reactions by using the operando XRD analysis. Regarding carbon species, we found that the over-potentials in the galvanostatic discharge-charge process were suppressed when using the KB carbon in the air electrode. The results of operando XRD measurements revealed that the Li{sub 2}O{sub 2} formed on the KB had the smaller crystalline or more amorphous like structures, which could be one reason for faster reaction kinetics of Li{sub 2}O{sub 2} dissolution. The discharge-charge curves of the cells with different concentration of LiTFSI/(G4){sub n} electrolyte showed the slight difference but less differences in the Li{sub 2}O{sub 2} formation and dissolution behaviors. In addition to the nature of Li{sub 2}O{sub 2} products, reaction of Li-salts would also have ineligible effects. We also found that the higher humidity in oxygen produced more the LiOH and promoted the Li{sub 2}O{sub 2} dissolution, which indicate that the LiOH formation could affect the Li{sub 2}O{sub 2} morphologies or surface chemistries. Our present results demonstrated that the operando XRD measurement are useful for analyzing the reaction mechanism of Li-O{sub 2} battery.

  1. The interaction of fatigue cracks with a residual stress field using thermoelastic stress analysis and synchrotron X-ray diffraction experiments

    Science.gov (United States)

    Amjad, Khurram; Asquith, David; Sebastian, Christopher M.; Wang, Wei-Chung

    2017-01-01

    This article presents an experimental study on the fatigue behaviour of cracks emanating from cold-expanded holes utilizing thermoelastic stress analysis (TSA) and synchrotron X-ray diffraction (SXRD) techniques with the aim of resolving the long-standing ambiguity in the literature regarding potential relaxation, or modification, of beneficial compressive residual stresses as a result of fatigue crack propagation. The crack growth rates are found to be substantially lower as the crack tip moved through the residual stress zone induced by cold expansion. The TSA results demonstrated that the crack tip plastic zones were reduced in size by the presence of the residual compressive stresses induced by cold expansion. The crack tip plastic zones were found to be insignificant in size in comparison to the residual stress zone resulting from cold expansion, which implied that they were unlikely to have had a notable impact on the surrounding residual stresses induced by cold expansion. The residual stress distributions measured along the direction of crack growth, using SXRD, showed no signs of any significant stress relaxation or redistribution, which validates the conclusions drawn from the TSA data. Fractographic analysis qualitatively confirmed the influence on crack initiation of the residual stresses induced by the cold expansion. It was found that the application of single compressive overload caused a relaxation, or reduction in the residual stresses, which has wider implications for improving the fatigue life. PMID:29291095

  2. A putative siderophore-interacting protein from the marine bacterium Shewanella frigidimarina NCIMB 400: cloning, expression, purification, crystallization and X-ray diffraction analysis

    Energy Technology Data Exchange (ETDEWEB)

    Trindade, Inês B.; Fonseca, Bruno M. [Universidade Nova de Lisboa, Avenida da República (EAN), 2780-157 Oeiras (Portugal); Matias, Pedro M. [Universidade Nova de Lisboa, Avenida da República (EAN), 2780-157 Oeiras (Portugal); Instituto de Biologia Experimental e Tecnológica (iBET), Apartado 12, 2780-901 Oeiras (Portugal); Louro, Ricardo O.; Moe, Elin, E-mail: elinmoe@itqb.unl.pt [Universidade Nova de Lisboa, Avenida da República (EAN), 2780-157 Oeiras (Portugal)

    2016-08-09

    The gene encoding a putative siderophore-interacting protein from the marine bacterium S. frigidimarina was successfully cloned, followed by expression and purification of the gene product. Optimized crystals diffracted to 1.35 Å resolution and preliminary crystallographic analysis is promising with respect to structure determination and increased insight into the poorly understood molecular mechanisms underlying iron acquisition. Siderophore-binding proteins (SIPs) perform a key role in iron acquisition in multiple organisms. In the genome of the marine bacterium Shewanella frigidimarina NCIMB 400, the gene tagged as SFRI-RS12295 encodes a protein from this family. Here, the cloning, expression, purification and crystallization of this protein are reported, together with its preliminary X-ray crystallographic analysis to 1.35 Å resolution. The SIP crystals belonged to the monoclinic space group P2{sub 1}, with unit-cell parameters a = 48.04, b = 78.31, c = 67.71 Å, α = 90, β = 99.94, γ = 90°, and are predicted to contain two molecules per asymmetric unit. Structure determination by molecular replacement and the use of previously determined ∼2 Å resolution SIP structures with ∼30% sequence identity as templates are ongoing.

  3. Detailed low-energy electron diffraction analysis of the (4×4) surface structure of C60 on Cu(111): Seven-atom-vacancy reconstruction

    Science.gov (United States)

    Xu, Geng; Shi, Xing-Qiang; Zhang, R. Q.; Pai, Woei Wu; Jeng, H. T.; Van Hove, M. A.

    2012-08-01

    A detailed and exhaustive structural analysis by low-energy electron diffraction (LEED) is reported for the C60-induced reconstruction of Cu(111), in the system Cu(111) + (4 × 4)-C60. A wide LEED energy range allows enhanced sensitivity to the crucial C60-metal interface that is buried below the 7-Å-thick molecular layer. The analysis clearly favors a seven-Cu-atom vacancy model (with Pendry R-factor Rp = 0.376) over a one-Cu-atom vacancy model (Rp = 0.608) and over nonreconstructed models (Rp = 0.671 for atop site and Rp = 0.536 for hcp site). The seven-Cu-atom vacancy forms a (4 × 4) lattice of bowl-like holes. In each hole, a C60 molecule can nestle by forming strong bonds (shorter than 2.30 Å) between 15 C atoms of the molecule and 12 Cu atoms of the outermost and second Cu layers.

  4. Neutron diffraction and lattice defects

    International Nuclear Information System (INIS)

    Hamaguchi, Yoshikazu

    1974-01-01

    Study on lattice defects by neutron diffraction technique is described. Wave length of neutron wave is longer than that of X-ray, and absorption cross-section is small. Number of defects observed by ESR is up to several defects, and the number studied with electron microscopes is more than 100. Information obtained by neutron diffraction concerns the number of defects between these two ranges. For practical analysis, several probable models are selected from the data of ESR or electron microscopes, and most probable one is determined by calculation. Then, defect concentration is obtained from scattering cross section. It is possible to measure elastic scattering exclusively by neutron diffraction. Minimum detectable concentration estimated is about 0.5% and 10 20 - 10 21 defects per unit volume. A chopper and a time of flight system are used as a measuring system. Cold neutrons are obtained from the neutron sources inserted into reactors. Examples of measurements by using similar equipments to PTNS-I system of Japan Atomic Energy Research Institute are presented. Interstitial concentration in the graphite irradiated by fast neutrons is shown. Defects in irradiated MgO were also investigated by measuring scattering cross section. Study of defects in Ge was made by measuring total cross section, and model analysis was performed in comparison with various models. (Kato, T.)

  5. Analysis of the average poly-cyclic aromatic unit in a meta-anthracite coal using conventional x-ray powder diffraction and intensity separation methods

    International Nuclear Information System (INIS)

    Wertz, D.L.; Bissell, M.

    1994-01-01

    X-ray characterizations of coals and coal products have occurred for many years. Hirsch and Cartz measured the diffraction from several coals over the reciprocal space region from s = 0.12 angstrom -1 to 7.5 angstrom -1 where s = (4π/λ) sinΘ. In these studies, a 9 cm powder camera was used to study the high angle region, and a transmission type focusing camera equipped with a LiF monochromator was used for the low angle measurements. They reported that the height of the graphene peak measured for each coal is proportional to the % carbon in the coals. Hirsch also suggested that the ontyberem anthracite has a lamellar diameter of ca. 16 angstrom corresponding to an aromatic lamellae of ca. C 87 . For coals with lower carbon content, Hirsch proposed much smaller lamellae; C 19 for a coal with 80% carbon, and C 24 for a coal with 89% carbon. The subject coal for this study is a meta-anthracite which was derived from the Portsmouth, RI mine. The Narragansett Basin contains anthracite and meta-anthracite coals of Pennsylvanian Age. The Basin was a techtonically active non-marine coal-forming basin which has been impacted by several tectonic events. Because of the importance placed by coal scientists no correctly characterizing the nature of the micro-level structural cluster(s) in coals and because of improvements in both x-ray experimentation capabilities and computing power, we have measured the x-ray diffraction and scattering produced from irradiation of this meta-anthracite coal which contains about 94% aromatic carbon. The goal of our study is to determine the intra-planar, and where possible, inter-planar structural details of coals. To accomplish this goal we have utilized the methods normally used for the molecular analysis of non-crystalline condensed phases such as liquids, solutions, and amorphous solids. Reported herein are the results obtained from the high angle x-ray analysis of this coal

  6. Diffraction in nuclear scattering

    International Nuclear Information System (INIS)

    Wojciechowski, H.

    1986-01-01

    The elastic scattering amplitudes for charged and neutral particles have been decomposed into diffractive and refractive parts by splitting the nuclear elastic scattering matrix elements into components responsible for these effects. It has been shown that the pure geometrical diffractive effect which carries no information about the nuclear interaction is always predominant at forward angle of elastic angular distributions. This fact suggests that for strongly absorbed particles only elastic cross section at backward angles, i.e. the refractive cross section, can give us basic information about the central nuclear potential. 12 refs., 4 figs., 1 tab. (author)

  7. Evaluation on double-wall-tube residual stress distribution of sodium-heated steam generator by neutron diffraction and numerical analysis

    International Nuclear Information System (INIS)

    Kisohara, N.; Suzuki, H.; Akita, K.; Kasahara, N.

    2012-01-01

    A double-wall-tube is nominated for the steam generator heat transfer tube of future sodium fast reactors (SFRs) in Japan, to decrease the possibility of sodium/water reaction. The double-wall-tube consists of an inner tube and an outer tube, and they are mechanically contacted to keep the heat transfer of the interface between the inner and outer tubes by their residual stress. During long term SG operation, the contact stress at the interface gradually falls down due to stress relaxation. This phenomenon might increase the thermal resistance of the interface and degrade the tube heat transfer performance. The contact stress relaxation can be predicted by numerical analysis, and the analysis requires the data of the initial residual stress distributions in the tubes. However, unclear initial residual stress distributions prevent precious relaxation evaluation. In order to resolve this issue, a neutron diffraction method was employed to reveal the tri-axial (radius, hoop and longitudinal) initial residual stress distributions in the double-wall-tube. Strain gauges also were used to evaluate the contact stress. The measurement results were analyzed using a JAEA's structural computer code to determine the initial residual stress distributions. Based on the stress distributions, the structural computer code has predicted the transition of the relaxation and the decrease of the contact stress. The radial and longitudinal temperature distributions in the tubes were input to the structural analysis model. Since the radial thermal expansion difference between the inner (colder) and outer (hotter) tube reduces the contact stress and the tube inside steam pressure contributes to increasing it, the analytical model also took these effects into consideration. It has been conduced that the inner and outer tubes are contacted with sufficient stresses during the plant life time, and that effective heat transfer degradation dose not occur in the double-wall-tube SG. (authors)

  8. Characterization of thermal reaction of aluminum/copper (II) oxide/poly(tetrafluoroethene) nanocomposite by thermogravimetric analysis, differential scanning calorimetry, mass spectrometry and X-ray diffraction

    International Nuclear Information System (INIS)

    Li, Xiangyu; Yang, Hongtao; Li, Yan-chun

    2015-01-01

    Highlights: • The thermal reaction properties of the Al/CuO/PTFE nanocomposite were investigated. • The Al/PTFE and CuO/PTFE nanocomposites were prepared and tested for comparison. • TG/DSC–MS and XRD analysis were performed. • PTFE is oxidizing Al and reducing CuO during the thermal decomposition. - Abstract: The application of fluoropolymers as reactive agent in energetic materials have attracted significant interest recently. In this study, the thermal reaction properties of the aluminum nanoparticles/copper (II) oxide nanoparticles/poly(tetrafluoroethene) (Al-NPs/CuO-NPs/PTFE) nanocomposite (mass ratio of Al-NPs/CuO-NPs/PTFE = 20/60/20) were investigated by means of thermogravimetry/differential scanning calorimetry–mass spectrometry (TG/DSC–MS) and X-ray diffraction (XRD) analyses. The Al-NPs/PTFE (mass ratio of Al-NPs/PTFE = 50/50) and CuO-NPs/PTFE (mass ratio of CuO-NPs/PTFE = 75/25) nanocomposites were also prepared and tested for comparison. It is observed that PTFE is acting as both oxidizer and reducer during the thermal decomposition process of Al-NPs/CuO-NPs/PTFE nanocomposites. Before 615 °C, PTFE is oxidized by CuO-NPs and oxidizing Al-NPs, resulting mass reduction. After 615 °C, the excessive aluminum and copper (I)/copper (II) oxide will proceed the exothermic condensed phase reaction.

  9. Zinc-Containing Restorations Create Amorphous Biogenic Apatite at the Carious Dentin Interface: A X-Ray Diffraction (XRD) Crystal Lattice Analysis.

    Science.gov (United States)

    Toledano, Manuel; Aguilera, Fátima S; López-López, Modesto T; Osorio, Estrella; Toledano-Osorio, Manuel; Osorio, Raquel

    2016-10-01

    The aim of this research was to assess the ability of amalgam restorations to induce amorphous mineral precipitation at the caries-affected dentin substrate. Sound and caries-affected dentin surfaces were subjected to both Zn-free and Zn-containing dental amalgam restorations. Specimens were submitted to thermocycling (100,000 cycles/5°C-55°C, 3 months). Dentin surfaces were studied by atomic force microscopy (nanoroughness), X-ray diffraction, field emission scanning electron microscopy, and energy-dispersive analysis, for physical and morphological surface characterization. Zn-containing amalgam placement reduced crystallinity, crystallite size, and grain size of calcium phosphate crystallites at the dentin surface. Both microstrain and nanoroughness were augmented in caries-affected dentin restored with Zn-containing amalgams. Caries-affected dentin showed the shortest mineral crystallites (11.04 nm), when Zn-containing amalgams were used for restorations, probably leading to a decrease of mechanical properties which might favor crack propagation and deformation. Sound dentin restored with Zn-free amalgams exhibited a substantial increase in length of grain particles (12.44 nm) embedded into dentin crystallites. Zn-containing amalgam placement creates dentin mineralization and the resultant mineral was amorphous in nature. Amorphous calcium phosphate provides a local ion-rich environment, which is considered favorable for in situ generation of prenucleation clusters, promotong further dentin remineralization.

  10. Analysis of X-ray diffraction of the titanium dioxide (TiO_2) synthesized by the Pechini Method for application in heterogeneous photocatalysis processes

    International Nuclear Information System (INIS)

    Oliveira, P.L.; Araujo, D.S.; Costa, A.C.F.M.; Oliveira, L.S.C.

    2016-01-01

    Titanium dioxide (TiO_2) is a polymorph commonly applied to heterogeneous photocatalysis processes for being relatively inexpensive and photo - stable. It is usually found in three different crystalline phases (anatase, rutile and brookite), which directly interfere in their photocatalytic efficiency. Therefore, this study aimed to investigate the obtainment of TiO_2 by Pechini method in different conditions for application in the heterogeneous photocatalysis process. For this purpose, it was evaluated by analysis of X-ray diffraction (XRD ) the behavior of TiO_2 materials synthesized in proportions of 2:1 and 3:1 (titanium isopropoxide/citric acid), pyrolyzed at 300°C/3h and 400°C /h and calcined at 400°C and 500°C/1h. The results revealed that the TiO_2 samples produced in the ratio of 2:1 and 3:1 isopropoxide/citric acid and calcined at 500°C/h presented the best results. (author)

  11. Mechanism of nanostructure formation in ball-milled Cu and Cu–3wt%Zn studied by X-ray diffraction line profile analysis

    International Nuclear Information System (INIS)

    Khoshkhoo, M. Samadi; Scudino, S.; Bednarcik, J.; Kauffmann, A.; Bahmanpour, H.; Freudenberger, J.; Scattergood, R.; Zehetbauer, M.J.; Koch, C.C.; Eckert, J.

    2014-01-01

    Highlights: • Nanostructured powders of Cu and Cu–3wt%Zn were produced using ball milling. • During cryomilling, nanostructure was formed by structural decomposition. • Dynamic recrystallization happened in room–temperature milling of Cu–3wt%Zn. • Structural decomposition took place during room–temperature milling of Cu. -- Abstract: The mechanism of nanostructure formation during cryogenic and room-temperature milling of Cu and Cu–3wt%Zn was investigated using X-ray diffraction line profile analysis. For that, the whole powder pattern modeling approach (WPPM) was used to analyze the evolution of microstructural features including coherently scattering domain size, dislocation density, and density of planar faults. It was found that for all sets of experiments, structural decomposition is the dominant mechanism of nanostructure formation during cryomilling. During subsequent RT-milling, grain refinement still occurs by structural decomposition for pure copper. On the other hand, discontinuous dynamic recrystallization is responsible for nanostructure formation during RT-milling of Cu–3wt%Zn. This is attributed to lower stacking-fault energy of Cu–3wt%Zn compared to pure copper. Finally, room temperature milling reveals the occurrence of a detwinning phenomenon

  12. Analysis of the dislocation content in a deformed Co-based superalloy by transmission electron microscopy and X-ray diffraction

    International Nuclear Information System (INIS)

    Breuer, D.; Klimanek, P.; Muehle, U.; Martin, U.

    1997-01-01

    The present paper compares the dislocation densities as determined in a Co-based superalloy (CoNi22Cr22W14) after creep and tensile deformation by Transmission Electron Microscopy (TEM) and X-ray profile analysis (XRD). After creep tests the dislocation densities obtained by both methods are in good agreement, which is the result of a nearly homogeneous dislocation distribution. The relationship between the dislocation density and the flow stress meets the Taylor equation. After tensile deformation the dislocation densities determined by TEM and XRD differ systematically from each other, but in both cases also a Taylor relationship can be obtained. The constant α of the dislocation interaction derived by TEM is much larger than in the creep tests and also than that of the XRD, which agrees well with the creep data. The difference between the TEM and the XRD results is the consequence of the dislocation cell structure much more developed in the tensile specimens, which leads to an underestimation of the dislocation density in TEM because of overweighting the cell interior. By fitting the Fourier coefficients of the X-ray diffraction line shapes with a bimodal distribution of the defect content (composite model), dislocation densities of the cell interior can be estimated that correspond well to the TEM data. (orig.)

  13. Analysis of a nanocrystalline polymer dispersion of ebselen using solid-state NMR, Raman microscopy, and powder X-ray diffraction.

    Science.gov (United States)

    Vogt, Frederick G; Williams, Glenn R

    2012-07-01

    Nanocrystalline drug-polymer dispersions are of significant interest in pharmaceutical delivery. The purpose of this work is to demonstrate the applicability of methods based on two-dimensional (2D) and multinuclear solid-state NMR (SSNMR) to a novel nanocrystalline pharmaceutical dispersion of ebselen with polyvinylpyrrolidone-vinyl acetate (PVP-VA), after initial characterization with other techniques. A nanocrystalline dispersion of ebselen with PVP-VA was prepared and characterized by powder X-ray diffraction (PXRD), confocal Raman microscopy and mapping, and differential scanning calorimetry (DSC), and then subjected to detailed 1D and 2D SSNMR analysis involving ¹H, ¹³C, and ⁷⁷Se isotopes and ¹H spin diffusion. PXRD was used to show that dispersion contains nanocrystalline ebselen in the 35-60 nm size range. Confocal Raman microscopy and spectral mapping were able to detect regions where short-range interactions may occur between ebselen and PVP-VA. Spin diffusion effects were analyzed using 2D SSNMR experiments and are able to directly detect interactions between ebselen and the surrounding PVP-VA. The methods used here, particularly the 2D SSNMR methods based on spin diffusion, provided detailed structural information about a nanocrystalline polymer dispersion of ebselen, and should be useful in other studies of these types of materials.

  14. Diffraction at collider energies

    International Nuclear Information System (INIS)

    Frankfurt, L.L.

    1992-01-01

    Lessons with ''soft'' hadron physics to explain (a) feasibility to observe and to investigate color transparency, color opacity effects at colliders; (b) significant probability and specific features of hard diffractive processes; (c) feasibility to investigate components of parton wave functions of hadrons with minimal number of constituents. This new physics would be more important with increase of collision energy

  15. Diffraction through partial identity

    International Nuclear Information System (INIS)

    Blum, W.

    1981-06-01

    A model of diffraction dissociation is proposed in which the quantum-mechanical interference between the incoming and the outgoing wave determines the cross-section. This interference occurs due to the finite life-time of the excited state. (orig.)

  16. Diffractive optics for industrial and commercial applications

    Energy Technology Data Exchange (ETDEWEB)

    Turunen, J. [Joensuu Univ. (Finland); Wyrowski, F. [eds.] [Jena Univ. (Germany)

    1997-12-31

    The following topics were dealt with: diffractive optics, diffraction gratings, optical system design with diffractive optics, continuous-relief diffractive lenses and microlens arrays, diffractive bifocal intraocular lenses, diffractive laser resonators, diffractive optics for semiconductor lasers, diffractive elements for optical image processing, photorefractive crystals in optical measurement systems, subwavelenth-structured elements, security applications, diffractive optics for solar cells, holographic microlithography. 999 refs.

  17. Diffraction Techniques in Structural Biology

    Science.gov (United States)

    Egli, Martin

    2016-01-01

    A detailed understanding of chemical and biological function and the mechanisms underlying the molecular activities ultimately requires atomic-resolution structural data. Diffraction-based techniques such as single-crystal X-ray crystallography, electron microscopy, and neutron diffraction are well established and they have paved the road to the stunning successes of modern-day structural biology. The major advances achieved in the last 20 years in all aspects of structural research, including sample preparation, crystallization, the construction of synchrotron and spallation sources, phasing approaches, and high-speed computing and visualization, now provide specialists and nonspecialists alike with a steady flow of molecular images of unprecedented detail. The present unit combines a general overview of diffraction methods with a detailed description of the process of a single-crystal X-ray structure determination experiment, from chemical synthesis or expression to phasing and refinement, analysis, and quality control. For novices it may serve as a stepping-stone to more in-depth treatises of the individual topics. Readers relying on structural information for interpreting functional data may find it a useful consumer guide. PMID:27248784

  18. Application of Powder Diffraction Methods to the Analysis of the Atomic Structure of Nanocrystals: The Concept of the Apparent Lattice Parameter (ALP)

    Science.gov (United States)

    Palosz, B.; Grzanka, E.; Gierlotka, S.; Stelmakh, S.; Pielaszek, R.; Bismayer, U.; Weber, H.-P.; Palosz, W.; Curreri, Peter A. (Technical Monitor)

    2002-01-01

    The applicability of standard methods of elaboration of powder diffraction data for determination of the structure of nano-size crystallites is analysed. Based on our theoretical calculations of powder diffraction data we show, that the assumption of the infinite crystal lattice for nanocrystals smaller than 20 nm in size is not justified. Application of conventional tools developed for elaboration of powder diffraction data, like the Rietveld method, may lead to erroneous interpretation of the experimental results. An alternate evaluation of diffraction data of nanoparticles, based on the so-called 'apparent lattice parameter' (alp) is introduced. We assume a model of nanocrystal having a grain core with well-defined crystal structure, surrounded by a surface shell with the atomic structure similar to that of the core but being under a strain (compressive or tensile). The two structural components, the core and the shell, form essentially a composite crystal with interfering, inseparable diffraction properties. Because the structure of such a nanocrystal is not uniform, it defies the basic definitions of an unambiguous crystallographic phase. Consequently, a set of lattice parameters used for characterization of simple crystal phases is insufficient for a proper description of the complex structure of nanocrystals. We developed a method of evaluation of powder diffraction data of nanocrystals, which refers to a core-shell model and is based on the 'apparent lattice parameter' methodology. For a given diffraction pattem, the alp values are calculated for every individual Bragg reflection. For nanocrystals the alp values depend on the diffraction vector Q. By modeling different a0tomic structures of nanocrystals and calculating theoretically corresponding diffraction patterns using the Debye functions we showed, that alp-Q plots show characteristic shapes which can be used for evaluation of the atomic structure of the core-shell system. We show, that using a simple

  19. Polarised neutron diffraction measurements of PrBa2Cu3O6+X and Bayesian statistical analysis of such data

    International Nuclear Information System (INIS)

    Markvardsen, A.J.

    2000-01-01

    The physics of the series Pr y Y 1-y Ba 2 CU 3 O 6+x , and ability of Pr to suppress superconductivity, has been a subject of frequent discussions in the literature for more than a decade. This thesis describes a polarised neutron diffraction (PND) experiment performed on PrBa 2 Cu 3 O 6.24 designed to find out something about the electron structure. This experiment pushed the limits of what can be done using the PND technique. The problem is one of a limited number of measured Fourier components that need to be inverted to form a real space image. To accomplish this inversion the maximum entropy technique has been employed. In some cases, the maximum entropy technique has the ability to increase the resolution of 'inverted' data immensely, but this ability is found to depend critically on the choice of constants used in the method. To investigate this a Bayesian robustness analysis of the maximum entropy method is carried out, resulting in an improvement of the maximum entropy technique for analysing PND data. Some results for nickel in the literature have been te-analysed and a comparison is made with different maximum entropy algorithms. Equipped with an improved data analysis technique and carefully measured PND data for PrBa 2 Cu 3 O 6.24 a number of new interesting features are observed, putting constraints on existing theoretical models of Pr y Y 1-y Ba 2 Cu 3 O 6+x and leaving room for more questions to be answered. (author)

  20. Application of Powder Diffraction Methods to the Analysis of Short- and Long-Range Atomic Order in Nanocrystalline Diamond and SiC: The Concept of the Apparent Lattice Parameter (alp)

    Science.gov (United States)

    Palosz, B.; Grzanka, E.; Gierlotka, S.; Stelmakh, S.; Pielaszek, R.; Bismayer, U.; Weber, H.-P.; Palosz, W.

    2003-01-01

    Two methods of the analysis of powder diffraction patterns of diamond and SiC nanocrystals are presented: (a) examination of changes of the lattice parameters with diffraction vector Q ('apparent lattice parameter', alp) which refers to Bragg scattering, and (b), examination of changes of inter-atomic distances based on the analysis of the atomic Pair Distribution Function, PDF. Application of these methods was studied based on the theoretical diffraction patterns computed for models of nanocrystals having (i) a perfect crystal lattice, and (ii), a core-shell structure, i.e. constituting a two-phase system. The models are defined by the lattice parameter of the grain core, thickness of the surface shell, and the magnitude and distribution of the strain field in the shell. X-ray and neutron experimental diffraction data of nanocrystalline SiC and diamond powders of the grain diameter from 4 nm up to micrometers were used. The effects of the internal pressure and strain at the grain surface on the structure are discussed based on the experimentally determined dependence of the alp values on the Q-vector, and changes of the interatomic distances with the grain size determined experimentally by the atomic Pair Distribution Function (PDF) analysis. The experimental results lend a strong support to the concept of a two-phase, core and the surface shell structure of nanocrystalline diamond and SiC.