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

NASA Technical Reports Server (NTRS)

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

2004-01-01

Phase-contrast X-ray diffraction imaging and high-angular-resolution diffraction combined with phase-contrast radiographic imaging were employed to characterize defects and perfection of a uniformly grown tetragonal lysozyme crystal in the symmetric Laue case. The full-width at half-maximum (FWHM) of a 4 4 0 rocking curve measured from the original crystal was approximately 16.7 arcsec and imperfections including line defects, inclusions and other microdefects were observed in the diffraction images of the crystal. The observed line defects carry distinct dislocation features running approximately along the <1 1 0> growth front and have been found to originate mostly in a central growth area and occasionally in outer growth regions. Inclusions of impurities or formations of foreign particles in the central growth region are resolved in the images with high sensitivity to defects. Slow dehydration led to the broadening of a fairly symmetric 4 4 0 rocking curve by a factor of approximately 2.6, which was primarily attributed to the dehydration-induced microscopic effects that are clearly shown in X-ray diffraction images. The details of the observed defects and the significant change in the revealed microstructures with drying provide insight into the nature of imperfections, nucleation and growth, and the properties of protein crystals.

X-ray plane-wave diffraction effects in a crystal with third-order nonlinearity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Balyan, M. K., E-mail: mbalyan@ysu.am

The two-wave dynamical diffraction in the Laue geometry has been theoretically considered for a plane X-ray wave in a crystal with a third-order nonlinear response to the external field. An analytical solution to the problem stated is found for certain diffraction conditions. A nonlinear pendulum effect is analyzed. The nonlinear extinction length is found to depend on the incident-wave intensity. A pendulum effect of a new type is revealed: the intensities of the transmitted and diffracted waves periodically depend on the incidentwave intensity at a fixed crystal thickness. The rocking curves and Borrmann nonlinear effect are numerically calculated.

Pressure-induced phase transition in GaN nanocrystals

NASA Astrophysics Data System (ADS)

Cui, Q.; Pan, Y.; Zhang, W.; Wang, X.; Zhang, J.; Cui, T.; Xie, Y.; Liu, J.; Zou, G.

2002-11-01

High-pressure in situ energy-dispersive x-ray diffraction experiments on GaN nanocrystals with 50 nm diameter have been carried out using a synchrotron x-ray source and a diamond-anvil cell up to about 79 GPa at room temperature. A pressure-induced first-order structural phase transition from the wurtzite-type structure to the rock-salt-type structure starts at about 48.8 GPa. The rock-salt-type phase persists to the highest pressure in our experimental range.

User Guide to RockJock - A Program for Determining Quantitative Mineralogy from X-Ray Diffraction Data

USGS Publications Warehouse

Eberl, D.D.

2003-01-01

RockJock is a computer program that determines quantitative mineralogy in powdered samples by comparing the integrated X-ray diffraction (XRD) intensities of individual minerals in complex mixtures to the intensities of an internal standard. Analysis without an internal standard (standardless analysis) also is an option. This manual discusses how to prepare and X-ray samples and mineral standards for these types of analyses and describes the operation of the program. Carefully weighed samples containing an internal standard (zincite) are ground in a McCrone mill. Randomly oriented preparations then are X-rayed, and the X-ray data are entered into the RockJock program. Minerals likely to be present in the sample are chosen from a list of standards, and the calculation is begun. The program then automatically fits the sum of stored XRD patterns of pure standard minerals (the calculated pattern) to the measured pattern by varying the fraction of each mineral standard pattern, using the Solver function in Microsoft Excel to minimize a degree of fit parameter between the calculated and measured pattern. The calculation analyzes the pattern (usually 20 to 65 degrees two-theta) to find integrated intensities for the minerals. Integrated intensities for each mineral then are determined from the proportion of each mineral standard pattern required to give the best fit. These integrated intensities then are compared to the integrated intensity of the internal standard, and the weight percentages of the minerals are calculated. The results are presented as a list of minerals with their corresponding weight percent. To some extent, the quality of the analysis can be checked because each mineral is analyzed independently, and, therefore, the sum of the analysis should approach 100 percent. Also, the method has been shown to give good results with artificial mixtures. The program is easy to use, but does require an understanding of mineralogy, of X-ray diffraction practice, and an elementary knowledge of the Excel program.

First use of portable system coupling X-ray diffraction and X-ray fluorescence for in-situ analysis of prehistoric rock art.

PubMed

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.

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

NASA Technical Reports Server (NTRS)

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

2003-01-01

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

Laboratory multiple-crystal X-ray topography and reciprocal-space mapping of protein crystals: influence of impurities on crystal perfection

NASA Technical Reports Server (NTRS)

Hu, Z. W.; Thomas, B. R.; Chernov, A. A.

2001-01-01

Double-axis multiple-crystal X-ray topography, rocking-curve measurements and triple-axis reciprocal-space mapping have been combined to characterize protein crystals using a laboratory source. Crystals of lysozyme and lysozyme crystals doped with acetylated lysozyme impurities were examined. It was shown that the incorporation of acetylated lysozyme into crystals of lysozyme induces mosaic domains that are responsible for the broadening and/or splitting of rocking curves and diffraction-space maps along the direction normal to the reciprocal-lattice vector, while the overall elastic lattice strain of the impurity-doped crystals does not appear to be appreciable in high angular resolution reciprocal-space maps. Multiple-crystal monochromatic X-ray topography, which is highly sensitive to lattice distortions, was used to reveal the spatial distribution of mosaic domains in crystals which correlates with the diffraction features in reciprocal space. Discussions of the influence of acetylated lysozyme on crystal perfection are given in terms of our observations.

Laboratory multiple-crystal X-ray topography and reciprocal-space mapping of protein crystals: influence of impurities on crystal perfection.

PubMed

Hu, Z W; Thomas, B R; Chernov, A A

2001-06-01

Double-axis multiple-crystal X-ray topography, rocking-curve measurements and triple-axis reciprocal-space mapping have been combined to characterize protein crystals using a laboratory source. Crystals of lysozyme and lysozyme crystals doped with acetylated lysozyme impurities were examined. It was shown that the incorporation of acetylated lysozyme into crystals of lysozyme induces mosaic domains that are responsible for the broadening and/or splitting of rocking curves and diffraction-space maps along the direction normal to the reciprocal-lattice vector, while the overall elastic lattice strain of the impurity-doped crystals does not appear to be appreciable in high angular resolution reciprocal-space maps. Multiple-crystal monochromatic X-ray topography, which is highly sensitive to lattice distortions, was used to reveal the spatial distribution of mosaic domains in crystals which correlates with the diffraction features in reciprocal space. Discussions of the influence of acetylated lysozyme on crystal perfection are given in terms of our observations.

Structure resolution by electron diffraction tomography of the complex layered iron-rich Fe-2234-type Sr{sub 5}Fe{sub 6}O{sub 15.4}

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lepoittevin, Christophe, E-mail: christophe.lepoittevin@neel.cnrs.fr

2016-10-15

The crystal structure of the strontium ferrite Sr{sub 5}Fe{sub 6}O{sub 15.4}, was solved by direct methods on electron diffraction tomography data acquired on a transmission electron microscope. The refined cell parameters are a=27.4047(3) Å, b=5.48590(7) Å and c=42.7442(4) Å in Fm2m symmetry. Its structure is built up from the intergrowth sequence between a quadruple perovskite-type layer with a complex rock-salt (RS)-type block. In the latter iron atoms are found in two different environments : tetragonal pyramid and tetrahedron. The structural model was refined by Rietveld method based on the powder X-ray diffraction pattern. - Highlights: • Complex structure of Sr{submore » 5}Fe{sub 6}O{sub 15.4} solved by electron diffraction tomography. • Observed Fourier maps allow determining missing oxygen atoms in the structure. • Structural model refined from powder X-ray diffraction data. • Intergrowth between quadruple perovskite layer with double rock-salt-type layer.« less

Energy Dispersive X-ray Diffraction (EDXRD) of Li1.1V3O8 Electrochemical Cell

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Qing; Bruck, Andrea M.; Bock, David C.

2017-01-01

ABSTRACT In this study, we conducted the first energy dispersive x-ray diffraction (EDXRD) experiments on Li/Li 1.1V 3O 8coin cells discharged to different lithiation levels in order to investigate the phase transitions upon electrochemical reduction. The phase transformation from layered Li-poor α to Li-rich α to defect rock-salt β phase was confirmed with cells of different lithiation stages. No spatial localization of phase formation was observed throughout the cathodes under the conditions of this measurement.

A novel multi-detection technique for three-dimensional reciprocal-space mapping in grazing-incidence X-ray diffraction.

PubMed

Schmidbauer, M; Schäfer, P; Besedin, S; Grigoriev, D; Köhler, R; Hanke, M

2008-11-01

A new scattering technique in grazing-incidence X-ray diffraction geometry is described which enables three-dimensional mapping of reciprocal space by a single rocking scan of the sample. This is achieved by using a two-dimensional detector. The new set-up is discussed in terms of angular resolution and dynamic range of scattered intensity. As an example the diffuse scattering from a strained multilayer of self-assembled (In,Ga)As quantum dots grown on GaAs substrate is presented.

Energy Dispersive X-ray Diffraction (EDXRD) of Li1.1V3O8 Electrochemical Cell

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Qing; Bruck, Andrea M.; Bock, David C.

ABSTRACT In this study, we conducted the first energy dispersive x-ray diffraction (EDXRD) experiments on Li/Li 1.1V 3O 8coin cells discharged to different lithiation levels in order to investigate the phase transitions upon electrochemical reduction. The phase transformation from layered Li-poor α to Li-rich α to defect rock-salt β phase was confirmed with cells of different lithiation stages. No spatial localization of phase formation was observed throughout the cathodes under the conditions of this measurement.

X-Ray Diffraction on Mars: Scientific Discoveries Made by the CheMin Instrument

NASA Technical Reports Server (NTRS)

Rampe, E. B.; Blake, D. F.; Ming, D. W.; Bristow, T. F.

2017-01-01

The Mars Science Laboratory Curiosity landed in Gale crater in August 2012 with the goal to identify and characterize habitable environments on Mars. Curiosity has been studying a series of sedimentary rocks primarily deposited in fluviolacustrine environments approximately 3.5 Ga. Minerals in the rocks and soils on Mars can help place further constraints on these ancient aqueous environments, including pH, salinity, and relative duration of liquid water. The Chemistry and Mineralogy (CheMin) X-ray diffraction and X-ray fluorescence instrument on Curiosity uses a Co X-ray source and charge-coupled device detector in transmission geometry to collect 2D Debye-Scherrer ring patterns of the less than 150 micron size fraction of drilled rock powders or scooped sediments. With an angular range of approximately 2.52deg 20 and a 20 resolution of approximately 0.3deg, mineral abundances can be quantified with a detection limit of approximately 1-2 wt. %. CheMin has returned quantitative mineral abundances from 16 mudstone, sandstone, and aeolian sand samples so far. The mineralogy of these samples is incredibly diverse, suggesting a variety of depositional and diagenetic environments and different source regions for the sediments. Results from CheMin have been essential for reconstructing the geologic history of Gale crater and addressing the question of habitability on ancient Mars.

Near-surface density profiling of Fe ion irradiated Si (100) using extremely asymmetric x-ray diffraction by variation of the wavelength

DOE Office of Scientific and Technical Information (OSTI.GOV)

Khanbabaee, B., E-mail: khanbabaee@physik.uni-siegen.de; Pietsch, U.; Facsko, S.

2014-10-20

In this work, we report on correlations between surface density variations and ion parameters during ion beam-induced surface patterning process. The near-surface density variations of irradiated Si(100) surfaces were investigated after off-normal irradiation with 5 keV Fe ions at different fluences. In order to reduce the x-ray probing depth to a thickness below 5 nm, the extremely asymmetrical x-ray diffraction by variation of wavelength was applied, exploiting x-ray refraction at the air-sample interface. Depth profiling was achieved by measuring x-ray rocking curves as function of varying wavelengths providing incidence angles down to 0°. The density variation was extracted from the deviationsmore » from kinematical Bragg angle at grazing incidence angles due to refraction of the x-ray beam at the air-sample interface. The simulations based on the dynamical theory of x-ray diffraction revealed that while a net near-surface density decreases with increasing ion fluence which is accompanied by surface patterning, there is a certain threshold of ion fluence to surface density modulation. Our finding suggests that the surface density variation can be relevant with the mechanism of pattern formation.« less

Pressure-induced structural transition in chalcopyrite ZnSiP2

NASA Astrophysics Data System (ADS)

Bhadram, Venkata S.; Krishna, Lakshmi; Toberer, Eric S.; Hrubiak, Rostislav; Greenberg, Eran; Prakapenka, Vitali B.; Strobel, Timothy A.

2017-05-01

The pressure-dependent phase behavior of semiconducting chalcopyrite ZnSiP2 was studied up to 30 GPa using in situ X-ray diffraction and Raman spectroscopy in a diamond-anvil cell. A structural phase transition to the rock salt type structure was observed between 27 and 30 GPa, which is accompanied by soft phonon mode behavior and simultaneous loss of Raman signal and optical transmission through the sample. The high-pressure rock salt type phase possesses cationic disorder as evident from broad features in the X-ray diffraction patterns. The behavior of the low-frequency Raman modes during compression establishes a two-stage, order-disorder phase transition mechanism. The phase transition is partially reversible, and the parent chalcopyrite structure coexists with an amorphous phase upon slow decompression to ambient conditions.

Time Resolved X-Ray Diffraction Study of Acoustoelectrically Amplified Phonons.

NASA Astrophysics Data System (ADS)

Chapman, Leroy Dean

X-rays diffracted by nearly perfect crystals of n-type InSb have been investigated in the presence of intense acoustoelectrically (A.E.) amplified phonons. The fact that these phonons are nearly monochromatic and have a well defined propagation and polarization direction presents an excellent opportunity to investigate the nature of x -ray photon-phonon scattering in a diffracting crystal. The Debye-Waller factor which accounts for the attenuation of diffracted x-ray intensities due to thermal phonons is reflection dependent owing to its sin (theta)/(lamda) dependence. We have performed experiments comparing the (004) and (008) anomalously transmitted intensities as a function of A.E. amplified flux. The attenuation of both reflections due to the amplified phonons was the same in direct contradiction to an expected sin (theta)/(lamda) dependence. Some possible reasons for this failure are discussed. In a Bragg reflection scattering geometry, the intense monochromatic amplified phonons give rise to satellite peaks symmetrically located about the central elastic Brag peak in a rocking profile. We report in this thesis on the first observation of satellites in a thin crystal Laue transmission geometry. We have theoretically simulated the rocking profiles with some success. The A.E. amplification process in InSb is strongly favored for {110} propagation fast transverse (FT) phonons. In earlier experiments it was found that non-{110} FT phonons were also produced during the amplification process. We have developed a time resolved x-ray counting system which, in conjunction with a spatially resolved x-ray beam and a localized, traveling A.E. phonon distribution, allow the time evolution of the amplified distribution to be followed. We report on time resolved measurements for both the symmetric Bragg and Laue geometries from which we can determine when and where non-{110 } FT flux is generated and restrict the possible mechanisms for its generation.

Penetration Depth and Defect Image Contrast Formation in Grazing-Incidence X-ray Topography of 4H-SiC Wafers

NASA Astrophysics Data System (ADS)

Yang, Yu; Guo, Jianqiu; Goue, Ouloide Yannick; Kim, Jun Gyu; Raghothamachar, Balaji; Dudley, Michael; Chung, Gill; Sanchez, Edward; Manning, Ian

2018-02-01

Synchrotron x-ray topography in grazing-incidence geometry is useful for discerning defects at different depths below the crystal surface, particularly for 4H-SiC epitaxial wafers. However, the penetration depths measured from x-ray topographs are much larger than theoretical values. To interpret this discrepancy, we have simulated the topographic contrast of dislocations based on two of the most basic contrast formation mechanisms, viz. orientation and kinematical contrast. Orientation contrast considers merely displacement fields associated with dislocations, while kinematical contrast considers also diffraction volume, defined as the effective misorientation around dislocations and the rocking curve width for given diffraction vector. Ray-tracing simulation was carried out to visualize dislocation contrast for both models, taking into account photoelectric absorption of the x-ray beam inside the crystal. The results show that orientation contrast plays the key role in determining both the contrast and x-ray penetration depth for different types of dislocation.

Big Sky and Greenhorn Drill Holes and CheMin X-ray Diffraction

NASA Image and Video Library

2015-12-17

The graph at right presents information from the NASA Curiosity Mars rover's onboard analysis of rock powder drilled from the "Big Sky" and "Greenhorn" target locations, shown at left. X-ray diffraction analysis of the Greenhorn sample inside the rover's Chemistry and Mineralogy (CheMin) instrument revealed an abundance of silica in the form of noncrystalline opal. The broad hump in the background of the X-ray diffraction pattern for Greenhorn, compared to Big Sky, is diagnostic of opal. The image of Big Sky at upper left was taken by the rover's Mars Hand Lens Imager (MAHLI) camera the day the hole was drilled, Sept. 29, 2015, during the mission's 1,119th Martian day, or sol. The Greenhorn hole was drilled, and the MAHLI image at lower left was taken, on Oct. 18, 2015 (Sol 1137). http://photojournal.jpl.nasa.gov/catalog/PIA20272

Studies on rock characteristics and timing of creep at selected landslide sites in Taiwan

Treesearch

Cheng-Yi Lee

2000-01-01

A study was conducted to investigate the causes of and rock characteristics at three landslide sites in the Tesngwen Reservoir watershed of southern Taiwan. Research methods used included the petrographic microscope, X-ray diffraction (XRD), scanning electron microscope (SEM), inductively coupled plasma spectroscope (ICP), constant head permeameter in triaxial...

Improving Beamline X-ray Optics by Analyzing the Damage to Crystallographic Structure

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zientek, John; Maj, Jozef; Navrotski, Gary

2015-01-02

The mission of the X-ray Characterization Laboratory in the X-ray Science Division (XSD) at the Advanced Photon Source (APS) is to support both the users and the Optics Fabrication Facility that produces high performance optics for synchrotron X-ray beamlines. The Topography Test Unit (TTU) in the X-ray Lab has been successfully used to characterize diffracting crystals and test monochromators by quantifying residual surface stresses. This topographic method has also been adapted for testing standard X-ray mirrors, characterizing concave crystal optics and in principle, can be used to visualize residual stresses on any optic made from single crystalline material. The TTUmore » has been instrumental in quantitatively determining crystal mounting stresses which are mechanically induced by positioning, holding, and cooling fixtures. It is this quantitative aspect that makes topography so useful since the requirements and responses for crystal optics and X-ray mirrors are quite different. In the case of monochromator crystals, even small residual or induced stresses, on the order of tens of kPa, can cause detrimental distortions to the perfect crystal rocking curves. Mirrors, on the other hand, are much less sensitive to induced stresses where stresses that are an order of magnitude greater can be tolerated. This is due to the fact that the surface rather than the lattice-spacing determines a mirror’s performance. For the highly sensitive crystal optics, it is essential to measure the in-situ rocking curves using topographs as mounting fixtures are adjusted. In this way, high heat-load monochromator crystals can be successfully mounted with minimum stress. Topographical analysis has been shown to be a highly effective method to visualize and quantify the distribution of stresses, to help identify methods that mitigate stresses, and most notably to improve diffractive crystal optic rocking curves.« less

Pressure-induced structural transition in chalcopyrite ZnSiP 2

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bhadram, Venkata S.; Krishna, Lakshmi; Toberer, Eric S.

The pressure-dependent phase behavior of semiconducting chalcopyrite ZnSiP 2 was studied up to 30 GPa using in situ X-ray diffraction and Raman spectroscopy in a diamond-anvil cell. A structural phase transition to the rock salt type structure was observed between 27 and 30 GPa, which is accompanied by soft phonon mode behavior and simultaneous loss of Raman signal and optical transmission through the sample. The high-pressure rock salt type phase possesses cationic disorder as evident from broad features in the X-ray diffraction patterns. The behavior of the low-frequency Raman modes during compression establishes a two-stage, order-disorder phase transition mechanism. Themore » phase transition is partially reversible, and the parent chalcopyrite structure coexists with an amorphous phase upon slow decompression to ambient conditions.« less

Diamond sensors and polycapillary lenses for X-ray absorption spectroscopy.

PubMed

Ravel, B; Attenkofer, K; Bohon, J; Muller, E; Smedley, J

2013-10-01

Diamond sensors are evaluated as incident beam monitors for X-ray absorption spectroscopy experiments. These single crystal devices pose a challenge for an energy-scanning experiment using hard X-rays due to the effect of diffraction from the crystalline sensor at energies which meet the Bragg condition. This problem is eliminated by combination with polycapillary lenses. The convergence angle of the beam exiting the lens is large compared to rocking curve widths of the diamond. A ray exiting one capillary from the lens meets the Bragg condition for any reflection at a different energy from the rays exiting adjacent capillaries. This serves to broaden each diffraction peak over a wide energy range, allowing linear measurement of incident intensity over the range of the energy scan. Extended X-ray absorption fine structure data are measured with a combination of a polycapillary lens and a diamond incident beam monitor. These data are of comparable quality to data measured without a lens and with an ionization chamber monitoring the incident beam intensity.

Mineralogy of parent rock and peaty-podzolic soil of Iremel Ridge, Southern Urals

NASA Astrophysics Data System (ADS)

Khalitov, R. M.; Perova, E. N.; Abakumov, E. V.; Suleimanov, R. R.

2017-08-01

The mineralogy of soils and parent rocks of the Iremel Ridge has been studied by the methods of micromorphology, laser diffraction, computed X-ray microtomography, and X-ray fluorescence analysis. In hard rock and soil, the major minerals have been identified: quartz, illite, and a chlorite-group mineral (Fe analogue of sudoite), as well as accessory minerals: monazite, xenotime, rutile, zircon, and florencite. It has been found that chlorite, illite, and quartz are present in all horizons of the studied peaty-podzolic soil. Insignificant amounts of mixed-layered mineral and kaolinite could be suggested in the T and EL horizons of peaty-podzolic soil. The mixed-layered mineral is most probably of soil origin, which is related to the transformation of illites inherited from the parent rock under acidic conditions.

Silica in Opal at Buckskin and Greenhorn on Mount Sharp

NASA Image and Video Library

2015-12-17

This graph presents information from the NASA Curiosity Mars rover's onboard analysis of rock powder drilled from the "Buckskin" and "Greenhorn" target locations on lower Mount Sharp. Buckskin, in the "Marias Pass" area, and Greenhorn, in the "Bridger Basin" area, both contain high concentrations of silica. X-ray diffraction analysis of powered samples inside Curiosity's Chemistry and Mineralogy (CheMin) instrument revealed that each of them contains silica in the form of noncrystalline opal. The broad hump in the two X-ray diffraction patterns is diagnostic of opaline silica. Some of the silica in Buckskin is in the form of tridymite. http://photojournal.jpl.nasa.gov/catalog/PIA20273

Low Energy X-Ray and γ-Ray Detectors Fabricated on n-Type 4H-SiC Epitaxial Layer

NASA Astrophysics Data System (ADS)

Mandal, Krishna C.; Muzykov, Peter G.; Chaudhuri, Sandeep K.; Terry, J. Russell

2013-08-01

Schottky barrier diode (SBD) radiation detectors have been fabricated on n-type 4H-SiC epitaxial layers and evaluated for low energy x- and γ-rays detection. The detectors were found to be highly sensitive to soft x-rays in the 50 eV to few keV range and showed 2.1 % energy resolution for 59.6 keV gamma rays. The response to soft x-rays for these detectors was significantly higher than that of commercial off-the-shelf (COTS) SiC UV photodiodes. The devices have been characterized by current-voltage (I-V) measurements in the 94-700 K range, thermally stimulated current (TSC) spectroscopy, x-ray diffraction (XRD) rocking curve measurements, and defect delineating chemical etching. I-V characteristics of the detectors at 500 K showed low leakage current ( nA at 200 V) revealing a possibility of high temperature operation. The XRD rocking curve measurements revealed high quality of the epitaxial layer exhibiting a full width at half maximum (FWHM) of the rocking curve 3.6 arc sec. TSC studies in a wide range of temperature (94-550 K) revealed presence of relatively shallow levels ( 0.25 eV) in the epi bulk with a density 7×1013 cm-3 related to Al and B impurities and deeper levels located near the metal-semiconductor interface.

Study of marbles from Middle Atlas (Morocco): elemental, mineralogical and structural analysis

NASA Astrophysics Data System (ADS)

Khrissi, S.; Bejjit, L.; Haddad, M.; Falguères, C.; Ait Lyazidi, S.; El Amraoui, M.

2018-05-01

A series of marbles sampled from the region of Middle Atlas (Morocco), are characterized by different complementary spectroscopic techniques. X-Ray fluorescence is used to determine elemental composition of rock while X-Ray diffraction and the Raman spectroscopy are used to determine major crystalline phases (calcite and dolomite) and minor ones (quartz).The samples display typical EPR spectra of Mn2+ in calcite and reveal the presence of Fe3+ ions.

Surface-treated self-standing curved crystals as high-efficiency elements for X- and γ-ray optics: theory and experiment.

PubMed

Bonnini, Elisa; Buffagni, Elisa; Zappettini, Andrea; Doyle, Stephen; Ferrari, Claudio

2015-06-01

The efficiency of a Laue lens for X- and γ-ray focusing in the energy range 60-600 keV is closely linked to the diffraction efficiency of the single crystals composing the lens. A powerful focusing system is crucial for applications like medical imaging and X-ray astronomy where wide beams must be focused. Mosaic crystals with a high density, such as Cu or Au, and bent crystals with curved diffracting planes (CDPs) are considered for the realization of a focusing system for γ-rays, owing to their high diffraction efficiency in a predetermined angular range. In this work, a comparison of the efficiency of CDP crystals and Cu and Au mosaic crystals was performed on the basis of the theory of X-ray diffraction. Si, GaAs and Ge CDP crystals with optimized thicknesses and moderate radii of curvature of several tens of metres demonstrate comparable or superior performance with respect to the higher atomic number mosaic crystals generally used. In order to increase the efficiency of the lens further, a stack of several CDP crystals is proposed as an optical element. CDP crystals were obtained by a surface-damage method, and a stack of two surface-damaged bent Si crystals was prepared and tested. Rocking curves of the stack were performed with synchrotron radiation at 19 keV to check the lattice alignment: they exhibited only one diffraction peak.

X-ray diffraction results from Mars Science Laboratory: mineralogy of Rocknest at Gale crater.

PubMed

Bish, D L; Blake, D F; Vaniman, D T; Chipera, S J; Morris, R V; Ming, D W; Treiman, A H; Sarrazin, P; Morrison, S M; Downs, R T; Achilles, C N; Yen, A S; Bristow, T F; Crisp, J A; Morookian, J M; Farmer, J D; Rampe, E B; Stolper, E M; Spanovich, N

2013-09-27

The Mars Science Laboratory rover Curiosity scooped samples of soil from the Rocknest aeolian bedform in Gale crater. Analysis of the soil with the Chemistry and Mineralogy (CheMin) x-ray diffraction (XRD) instrument revealed plagioclase (~An57), forsteritic olivine (~Fo62), augite, and pigeonite, with minor K-feldspar, magnetite, quartz, anhydrite, hematite, and ilmenite. The minor phases are present at, or near, detection limits. The soil also contains 27 ± 14 weight percent x-ray amorphous material, likely containing multiple Fe(3+)- and volatile-bearing phases, including possibly a substance resembling hisingerite. The crystalline component is similar to the normative mineralogy of certain basaltic rocks from Gusev crater on Mars and of martian basaltic meteorites. The amorphous component is similar to that found on Earth in places such as soils on the Mauna Kea volcano, Hawaii.

Large-surface-area diamond (111) crystal plates for applications in high-heat-load wavefront-preserving X-ray crystal optics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stoupin, Stanislav; Antipov, Sergey; Butler, James E.

Fabrication and results of high-resolution X-ray topography characterization of diamond single-crystal plates with large surface area (10 mm × 10 mm) and (111) crystal surface orientation for applications in high-heat-load X-ray crystal optics are reported. The plates were fabricated by laser-cutting of the (111) facets of diamond crystals grown using high-pressure high-temperature methods. The intrinsic crystal quality of a selected 3 mm × 7 mm crystal region of one of the studied samples was found to be suitable for applications in wavefront-preserving high-heat-load crystal optics. Wavefront characterization was performed using sequential X-ray diffraction topography in the pseudo plane wave configurationmore » and data analysis using rocking-curve topography. In conclusion, the variations of the rocking-curve width and peak position measured with a spatial resolution of 13 µm × 13 µm over the selected region were found to be less than 1 µrad.« less

Large-surface-area diamond (111) crystal plates for applications in high-heat-load wavefront-preserving X-ray crystal optics.

PubMed

Stoupin, Stanislav; Antipov, Sergey; Butler, James E; Kolyadin, Alexander V; Katrusha, Andrey

2016-09-01

Fabrication and results of high-resolution X-ray topography characterization of diamond single-crystal plates with large surface area (10 mm × 10 mm) and (111) crystal surface orientation for applications in high-heat-load X-ray crystal optics are reported. The plates were fabricated by laser-cutting of the (111) facets of diamond crystals grown using high-pressure high-temperature methods. The intrinsic crystal quality of a selected 3 mm × 7 mm crystal region of one of the studied samples was found to be suitable for applications in wavefront-preserving high-heat-load crystal optics. Wavefront characterization was performed using sequential X-ray diffraction topography in the pseudo plane wave configuration and data analysis using rocking-curve topography. The variations of the rocking-curve width and peak position measured with a spatial resolution of 13 µm × 13 µm over the selected region were found to be less than 1 µrad.

Large-surface-area diamond (111) crystal plates for applications in high-heat-load wavefront-preserving X-ray crystal optics

DOE PAGES

Stoupin, Stanislav; Antipov, Sergey; Butler, James E.; ...

2016-08-10

Fabrication and results of high-resolution X-ray topography characterization of diamond single-crystal plates with large surface area (10 mm × 10 mm) and (111) crystal surface orientation for applications in high-heat-load X-ray crystal optics are reported. The plates were fabricated by laser-cutting of the (111) facets of diamond crystals grown using high-pressure high-temperature methods. The intrinsic crystal quality of a selected 3 mm × 7 mm crystal region of one of the studied samples was found to be suitable for applications in wavefront-preserving high-heat-load crystal optics. Wavefront characterization was performed using sequential X-ray diffraction topography in the pseudo plane wave configurationmore » and data analysis using rocking-curve topography. In conclusion, the variations of the rocking-curve width and peak position measured with a spatial resolution of 13 µm × 13 µm over the selected region were found to be less than 1 µrad.« less

Documenting mudstone heterogeneity by use of principal component analysis of X-ray diffraction and portable X-ray fluorescence data: A case study in the Triassic Shublik Formation, Alaska North Slope

USGS Publications Warehouse

Boehlke, Adam; Whidden, Katherine J.; Benzel, William M.

2017-01-01

Determining the chemical and mineralogical variability within fine-grained mudrocks poses analytical challenges but is potentially useful for documenting subtle stratigraphic differences in physicochemical environments that may influence petroleum reservoir properties and behavior. In this study, we investigate the utility of combining principal component analysis (PCA) of X-ray diffraction (XRD) data and portable X-ray fluorescence (pXRF) data to identify simplifying relationships within a large number of samples and subsequently evaluate a subset that encompasses the full spectrum or range of mineral and chemical variability within a vertical section. Samples were collected and analyzed from a vertical core of the Shublik Formation, a heterogeneous, phosphate-rich, calcareous mudstone-to-marl unit deposited in the Arctic Alaska Basin (AAB) during the Middle and Late Triassic. The Shublik is a major petroleum source rock in the Alaskan North Slope, and is considered a prime target for continuous self-sourced resource plays.

Remote In-Situ Quantitative Mineralogical Analysis Using XRD/XRF

NASA Technical Reports Server (NTRS)

Blake, D. F.; Bish, D.; Vaniman, D.; Chipera, S.; Sarrazin, P.; Collins, S. A.; Elliott, S. T.

2001-01-01

X-Ray Diffraction (XRD) is the most direct and accurate method for determining mineralogy. The CHEMIN XRD/XRF instrument has shown promising results on a variety of mineral and rock samples. Additional information is contained in the original extended abstract.

Improved microstructure of cement-based composites through the addition of rock wool particles

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lin, Wei-Ting; Institute of Nuclear Energy Research, Atomic Energy Council, Taoyuan 32546, Taiwan; Cheng, An, E-mail: ancheng@niu.edu.tw

2013-10-15

Rock wool is an inorganic fibrous substance produced by steam blasting and cooling molten glass. As with other industrial by-products, rock wool particles can be used as cementitious materials or ultra fine fillers in cement-based composites. This study investigated the microstructure of mortar specimens produced with cement-based composites that include various forms of rock wool particles. It conducted compressive strength testing, rapid chloride penetration tests, X-ray diffraction analysis, thermo-gravimetric analysis, and scanning electronic microscopy to evaluate the macro- and micro-properties of the cement-based composites. Test results indicate that inclusion of rock wool particles in composites improved compressive strength and reducedmore » chloride ion penetration at the age of 91 days due to the reduction of calcium hydroxide content. Microscopic analysis confirms that the use of rock wool particles contributed to the formation of a denser, more compact microstructure within the hardened paste. In addition, X-ray diffraction analysis shows few changes in formation of pozzolanic reaction products and no new hydrations are formed with incorporating rock wool particles. - Highlights: • We report the microstructural characterization of cement-based composites. • Different mixes produced with various rock wool particles have been tested. • The influence of different mixes on macro and micro properties has been discussed. • The macro properties are included compressive strength and permeability. • XRD and SEM observations confirm the pozzolanic reaction in the resulting pastes.« less

Powder X-ray diffraction laboratory, Reston, Virginia

USGS Publications Warehouse

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

2014-01-01

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

Detection Limit of Smectite by Chemin IV Laboratory Instrument: Preliminary Implications for Chemin on the Mars Science Laboratory Mission

NASA Technical Reports Server (NTRS)

Archilles, Cherie; Ming, D. W.; Morris, R. V.; Blake, D. F.

2011-01-01

The CheMin instrument on the Mars Science Laboratory (MSL) is an miniature X-ray diffraction (XRD) and X-ray fluorescence (XRF) instrument capable of detecting the mineralogical and elemental compositions of rocks, outcrops and soils on the surface of Mars. CheMin uses a microfocus-source Co X-ray tube, a transmission sample cell, and an energy-discriminating X-ray sensitive CCD to produce simultaneous 2-D XRD patterns and energy-dispersive X-ray histograms from powdered samples. CRISM and OMEGA have identified the presence of phyllosilicates at several locations on Mars including the four candidate MSL landing sites. The objective of this study was to conduct preliminary studies to determine the CheMin detection limit of smectite in a smectite/olivine mixed mineral system.

In Situ Mineralogical Analysis of Planetary Materials Using X-Ray Diffraction and X-Ray Fluorescence

NASA Technical Reports Server (NTRS)

Sarrazin, P.; Blake, D.; Vaniman, D.; Chang, Sherwood (Technical Monitor)

1996-01-01

Remote observations of Mars have led scientists to believe that its early climate was similar to that of the early Earth, having had abundant liquid water and a dense atmosphere. One of the most fascinating questions of recent times is whether simple bacterial life developed on Mars (as it did on the Earth) during this early element period. Analyses of SNC meteorites have broadened considerably our knowledge of the chemistry of certain types of Martian rocks, underscoring the tantalizing possibility of early hydrothermal systems and even of ancient bacterial life. Detailed analyses of SNC meteorites in Terrestrial laboratories utilize the most sophisticated organic, isotopic and microscopic techniques in existence. Indeed; it is unlikely that the key biogenic indicators used in McKay et al (ibid) could be identified by a remote instrument on the surface of Mars. As a result, it is probable that any robotic search for evidence of an ancient Martian biosphere will have as its focus the identification of key minerals in likely host rocks rather than the direct detection of organic or isotopic biomarkers. Even on a sample return mission, mineralogical screening will be utilized to choose the most likely candidate rocks. X-ray diffraction (XRD) is the only technique that can provide a direct determination of the crystal structures of the phases present within a sample. When many different crystalline phases are present, quantitative analysis is better constrained if used in conjunction with a determination of elemental composition, obtainable by X-ray fluorescence (XRF) using the same X-ray source as for XRD. For planetary surface analysis, a remote instrument combining XRD and XRF could be used for mineralogical characterization of both soils and rocks. We are designing a remote XRD/XRF instrument with this objective in mind. The instrument concept pays specific attention to constraints in sample preparation, weight, volume, power, etc. Based on the geometry of a pinhole camera (transmission geometry, flat two-dimensional detector perpendicular to the direct beam), the instrument (which we call CHEMIN, for Chemistry and Mineralogy) uses an X-ray sensitive CCD detector which will allow concurrent positional and energy-dispersive analysis of collected photons. Thus XRF (energy) and XRD (geometry) analysis of transmitted X-rays will be performed at the same time. Tests performed with single minerals and simple mixtures give promising results. Refinements of the prototype promise interpretable results on complex samples.

Experimental and theoretical investigation of the rocking curves measured for Mo K α X-ray characteristic lines in the double-crystal nondispersive scheme

NASA Astrophysics Data System (ADS)

Marchenkov, N. V.; Chukhovskii, F. N.; Blagov, A. E.

2015-03-01

The rocking curves (RCs) for Mo K α1 h Mo K α2 characteristic X-ray lines have been experimentally and theoretically studied in the nondispersive scheme of an X-ray double-crystal TPC-K diffractometer. The results of measurements and theoretical calculations of double-crystal RCs for characteristic X-rays from tubes with a molybdenum anode and different widths of slits show that a decrease in the slit width leads to an increase in the relative contribution of the Mo K α2-line RC in comparison with the intensity of the tails of the Mo K α1-line RC. It is shown that the second peak of the Mo K α2 line becomes increasingly pronounced in the tail of the Mo K α1-line RC with a decrease in the slit width. Two plane-parallel Si plates (input faces {110}, diffraction vector h <220>) were used as a monochromator crystal and a sample. The results of measuring double-crystal RCs are in good agreement with theoretical calculations.

Fabrication and convergent X-ray nanobeam diffraction characterization of submicron-thickness SrTiO 3 crystalline sheets

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tilka, J. A.; Park, J.; Sampson, K. C.

The creation of thin SrTiO3 crystals from (001)-oriented SrTiO3 bulk single crystals using focused ion beam milling techniques yields sheets with submicron thickness and arbitrary orientation within the (001) plane. Synchrotron x-ray nanodiffraction rocking curve widths of these SrTiO3 sheets are less than 0.02 degrees, less than a factor of two larger than bulk SrTiO3, making these crystals suitable substrates for epitaxial thin film growth. The change in the rocking curve width is sufficiently small that we deduce that dislocations are not introduced into the SrTiO3 sheets. Observed lattice distortions are consistent with a low concentration of point defects.

The first X-ray diffraction measurements on Mars.

PubMed

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

2014-11-01

The Mars Science Laboratory landed in Gale crater on Mars in August 2012, and the Curiosity rover then began field studies on its drive toward Mount Sharp, a central peak made of ancient sediments. CheMin is one of ten instruments on or inside the rover, all designed to provide detailed information on the rocks, soils and atmosphere in this region. CheMin is a miniaturized X-ray diffraction/X-ray fluorescence (XRD/XRF) instrument that uses transmission geometry with an energy-discriminating CCD detector. CheMin uses onboard standards for XRD and XRF calibration, and beryl:quartz mixtures constitute the primary XRD standards. Four samples have been analysed by CheMin, namely a soil sample, two samples drilled from mudstones and a sample drilled from a sandstone. Rietveld and full-pattern analysis of the XRD data reveal a complex mineralogy, with contributions from parent igneous rocks, amorphous components and several minerals relating to aqueous alteration. In particular, the mudstone samples all contain one or more phyllosilicates consistent with alteration in liquid water. In addition to quantitative mineralogy, Rietveld refinements also provide unit-cell parameters for the major phases, which can be used to infer the chemical compositions of individual minerals and, by difference, the composition of the amorphous component.

Measurement and models of bent KAP(001) crystal integrated reflectivity and resolution (invited)

NASA Astrophysics Data System (ADS)

Loisel, G. P.; Wu, M.; Stolte, W.; Kruschwitz, C.; Lake, P.; Dunham, G. S.; Bailey, J. E.; Rochau, G. A.

2016-11-01

The Advanced Light Source beamline-9.3.1 x-rays are used to calibrate the rocking curve of bent potassium acid phthalate (KAP) crystals in the 2.3-4.5 keV photon-energy range. Crystals are bent on a cylindrically convex substrate with a radius of curvature ranging from 2 to 9 in. and also including the flat case to observe the effect of bending on the KAP spectrometric properties. As the bending radius increases, the crystal reflectivity converges to the mosaic crystal response. The X-ray Oriented Programs (xop) multi-lamellar model of bent crystals is used to model the rocking curve of these crystals and the calibration data confirm that a single model is adequate to reproduce simultaneously all measured integrated reflectivities and rocking-curve FWHM for multiple radii of curvature in both 1st and 2nd order of diffraction.

Measurement and models of bent KAP(001) crystal integrated reflectivity and resolution (invited)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Loisel, G. P., E-mail: gploise@sandia.gov; Wu, M.; Lake, P.

2016-11-15

The Advanced Light Source beamline-9.3.1 x-rays are used to calibrate the rocking curve of bent potassium acid phthalate (KAP) crystals in the 2.3-4.5 keV photon-energy range. Crystals are bent on a cylindrically convex substrate with a radius of curvature ranging from 2 to 9 in. and also including the flat case to observe the effect of bending on the KAP spectrometric properties. As the bending radius increases, the crystal reflectivity converges to the mosaic crystal response. The X-ray Oriented Programs (XOP) multi-lamellar model of bent crystals is used to model the rocking curve of these crystals and the calibration datamore » confirm that a single model is adequate to reproduce simultaneously all measured integrated reflectivities and rocking-curve FWHM for multiple radii of curvature in both 1st and 2nd order of diffraction.« less

Growth of high quality and large-sized Rb 0.3MoO 3 single crystals by molten salt electrolysis method

NASA Astrophysics Data System (ADS)

Wang, Junfeng; Xiong, Rui; Yi, Fan; Yin, Di; Ke, Manzhu; Li, Changzhen; Liu, Zhengyou; Shi, Jing

2005-05-01

High quality and large-sized Rb 0.3MoO 3 single crystals were synthesized by molten salt electrolysis method. X-ray diffraction (XRD) patterns and rocking curves, as well as the white beam Laue diffraction of X-ray images show the crystals grown by this method have high quality. The lattice constants evaluated from XRD patterns are a0=1.87 nm, b0=0.75 nm, c0=1.00 nm, β=118.83∘. The in situ selected area electron diffraction (SAED) patterns along the [101¯], [11¯1¯] and [103¯] zone axes at room temperature indicate that the Rb 0.3MoO 3 crystal possess perfect C-centered symmetry. Temperature dependence of the resistivity shows this compound undergoes a metal to semiconductor transition at 183 K.

Shape and Size of Microfine Aggregates: X-ray Microcomputed Tomgraphy vs. Laser Diffraction

DOE Office of Scientific and Technical Information (OSTI.GOV)

Erdogan,S.; Garboczi, E.; Fowler, D.

Microfine rock aggregates, formed naturally or in a crushing process, pass a No. 200 ASTM sieve, so have at least two orthogonal principal dimensions less than 75 {mu}m, the sieve opening size. In this paper, for the first time, we capture true 3-D shape and size data of several different types of microfine aggregates, using X-ray microcomputed tomography ({mu}CT) with a voxel size of 2 {mu}m. This information is used to generate shape analyses of various kinds. Particle size distributions are also generated from the {mu}CT data and quantitatively compared to the results of laser diffraction, which is the leadingmore » method for measuring particle size distributions of sub-millimeter size particles. By taking into account the actual particle shape, the differences between {mu}CT and laser diffraction can be qualitatively explained.« less

The El Horror uranium anomaly in northeastern Sonora, Mexico: Constraints from geochemical and mineralogical approaches

NASA Astrophysics Data System (ADS)

Grijalva-Rodríguez, T.; Valencia-Moreno, M.; Calmus, T.; Del Rio-Salas, R.; Balcázar-García, M.

2017-12-01

This work reviews the characteristics of the El Horror uranium prospect in northeastern Sonora, Mexico. It was formerly detected by a radiometric anomaly after airborne gamma ray exploration carried out in the 70's by the Mexican government. As a promising site to contain important uranium resources, the El Horror was re-evaluated by CFE (Federal Electricity Commission) by in situ gamma ray surveys. The study also incorporates rock and stream sediment ICP-MS geochemistry, X-ray diffraction, X-ray fluorescence, Raman spectrometry and Scanning Electron Microscopy (SEM) to provide a better understanding of the radiometric anomaly. The results show that, instead of a single anomaly, it comprises at least five individual anomalies hosted in hydrothermally altered Laramide (80-40 Ma) andesitic volcanic rocks of the Tarahumara Formation. Concentrations for elemental uranium and uranium calculated from gamma ray surveys (i.e., equivalent uranium) are not spatially coincident within the anomaly, but, at least at some degree, they do so in specific sites. X-ray diffraction and Raman spectrometry revealed the presence of rutile/anatase, uvite, bukouvskyte and allanite as the more likely mineral phases to contain uranium. SEM studies revealed a process of iron-rich concretion formation, suggesting that uranium was initially incorporated to the system by adsorption, but was largely removed later during incorporation of Fe+3 ions. Stream sediment geochemistry reveals that the highest uranium concentrations are derived from the southern part of the Sierra La Madera batholith (∼63 Ma), and decrease toward the El Horror anomaly.

Studying Ultradisperse Diamond Structure within Explosively Synthesized Samples via X-Ray Techniques

NASA Astrophysics Data System (ADS)

Sharkov, M. D.; Boiko, M. E.; Ivashevskaya, S. N.; Belyakova, N. S.

2013-08-01

XRD (X-Ray Diffraction) and SAXS (Small-Angle X-Ray Scattering) data have been measured for a pair of samples produced with the help of explosives. XRD peaks have shown the both samples to contain crystal diamond components as well as graphite ones. Basing on SAXS analysis, possible presence of grains with radii up to 30-50 nm within all the samples has been shown. Structure components with fractal dimension between 1 and 2 in the sample have been detected, this fact being in agreement with the assumption of diamond grain coating similarity to onion shells. In order to broad rocking curves analysis, the standard SAXS treatment technique has been complemented by a Fourier filtering procedure. For the sample #1, rocking curve components corresponding to individual interplanar distances with magnitudes from 5 nm up to 15 nm have been separated. A hypothesis relating these values to the distances between concentric onion-like shells of diamond grains has been formulated.

Geospatial compilation of results from field sample collection in support of mineral resource investigations, Western Alaska Range, Alaska, July 2013

USGS Publications Warehouse

Johnson, Michaela R.; Graham, Garth E.; Hubbard, Bernard E.; Benzel, William M.

2015-07-16

This Data Series summarizes results from July 2013 sampling in the western Alaska Range near Mount Estelle, Alaska. The fieldwork combined in situ and camp-based spectral measurements of talus/soil and rock samples. Five rock and 48 soil samples were submitted for quantitative geochemi­cal analysis (for 55 major and trace elements), and the 48 soils samples were also analyzed by x-ray diffraction to establish mineralogy and geochemistry. The results and sample photo­graphs are presented in a geodatabase that accompanies this report. The spectral, mineralogical, and geochemical charac­terization of these samples and the sites that they represent can be used to validate existing remote-sensing datasets (for example, ASTER) and future hyperspectral studies. Empiri­cal evidence of jarosite (as identified by x-ray diffraction and spectral analysis) corresponding with gold concentrations in excess of 50 parts per billion in soil samples suggests that surficial mapping of jarosite in regional surveys may be use­ful for targeting areas of prospective gold occurrences in this sampling area.

Iron-containing pigment from an archaeological rupestrian painting of the Planalto Tradition in Minas Gerais, Brazil

NASA Astrophysics Data System (ADS)

Floresta, D. L.; Fagundes, M.; Fabris, J. D.; Ardisson, J. D.

2015-06-01

Archaeological rupestrian arts of the Planalto Tradition are of relatively widespread occurrence all over the land area of the state of Minas Gerais (MG), Brazil. They are typically composed by monochromic zoomorphic figures, especially of cervids, mainly in red or orange color. A fragment of a rock wall containing an archaeological painting was collected at the Itanguá site, in the municipality of Senador Modestino Gonçalves (geographical coordinates, 17° 56' 51″ S 43° 13' 22″ W), MG. The rock piece was covered with an archaeological painting with pigments of two different hues of red. The X-ray fluorescence (XRF) analysis revealed only a slight difference in Fe and P content for the two different color zones. The pigment materials on this small fragment of rock were analyzed by X-ray diffraction on the conventional incidence mode (XRD) and on grazing incidence X-ray mode (GIXRD), scanning electron microscopy with energy dispersive x-ray detector (SEM/EDS) and conversion electron Mössbauer spectroscopy (CEMS) at room temperature. Results indicated the occurrence of mainly hematite but also of diopside in the pigment. CEMS at RT reveal the presence of hematite and (super)paramagnetic ferric components. In order to confirm these results a small amount of powder from the painting pigments was also analyzed by transmission Mössbauer spectroscopy at 20 K.

New insights into microstructural evolution of epitaxial Ni-Mn-Ga films on MgO (1 0 0) substrate by high-resolution X-ray diffraction and orientation imaging investigations

NASA Astrophysics Data System (ADS)

Sharma, Amit; Mohan, Sangeneni; Suwas, Satyam

2018-04-01

In this work, a detailed investigation has been performed on hetero-epitaxial growth and microstructural evolution in highly oriented Ni-Mn-Ga (1 0 0) films grown on MgO (1 0 0) substrate using high-resolution X-ray diffraction and orientation imaging microscopy. Mosaicity of the films has been analysed in terms of tilt angle, twist angle, lateral and vertical coherence length and threading dislocation densities by performing rocking curve measurements and reciprocal space mapping. Density of edge dislocations is found to be an order of magnitude higher than the density of screw dislocations, irrespective of film thickness. X-ray pole figure measurements have revealed an orientation relationship of ? || (1 0 0)MgO; ? || [0 0 1]MgO between the film and substrate. Microstructure predicted by X-ray diffraction is in agreement with that obtained from electron microscopy and atomic force microscopy. The evolution of microstructure in the film with increasing thickness has been explained vis-à-vis dislocation generation and growth mechanisms. Orientation imaging microscopy observations indicate evolutionary growth of film by overgrowth mechanism. Decrease in coercivity with film thickness has been explained as an interplay between stress field developed due to crystal defects and magnetic domain pinning due to surface roughness.

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

DOEpatents

Lopez, Daniel; Shenoy, Gopal; Wang, Jin; Walko, Donald A.; Jung, Il-Woong; Mukhopadhyay, Deepkishore

2016-08-09

A method and apparatus are provided for implementing Bragg-diffraction leveraged modulation of X-ray pulses using MicroElectroMechanical systems (MEMS) based diffractive optics. An oscillating crystalline MEMS device generates a controllable time-window for diffraction of the incident X-ray radiation. The Bragg-diffraction leveraged modulation of X-ray pulses includes isolating a particular pulse, spatially separating individual pulses, and spreading a single pulse from an X-ray pulse-train.

Attainable high capacity in Li-excess Li-Ni-Ru-O rock-salt cathode for lithium ion battery

NASA Astrophysics Data System (ADS)

Wang, Xingbo; Huang, Weifeng; Tao, Shi; Xie, Hui; Wu, Chuanqiang; Yu, Zhen; Su, Xiaozhi; Qi, Jiaxin; Rehman, Zia ur; Song, Li; Zhang, Guobin; Chu, Wangsheng; Wei, Shiqiang

2017-08-01

Peroxide structure O2n- has proven to appear after electrochemical process in many lithium-excess precious metal oxides, representing extra reversible capacity. We hereby report construction of a Li-excess rock-salt oxide Li1+xNi1/2-3x/2Ru1/2+x/2O2 electrode, with cost effective and eco-friendly 3d transition metal Ni partially substituting precious 4d transition metal Ru. It can be seen that O2n- is formed in pristine Li1.23Ni0.155Ru0.615O2, and stably exists in subsequent cycles, enabling discharge capacities to 295.3 and 198 mAh g-1 at the 1st/50th cycle, respectively. Combing ex-situ X-ray absorption near edge spectroscopy, X-ray photoelectron spectroscopy, X-ray diffraction, high resolution transmission electron microscopy and electrochemical characterization, we demonstrate that the excellent electrochemical performance comes from both percolation network with disordered structure and cation/anion redox couples occurring in charge-discharge process. Li-excess and substitution of common element have been demonstrated to be a breakthrough for designing novel high performance commercial cathodes in rechargeable lithium ion battery field.

Experimental and theoretical investigation of the rocking curves measured for MoK{sub α} X-ray characteristic lines in the double-crystal nondispersive scheme

DOE Office of Scientific and Technical Information (OSTI.GOV)

Marchenkov, N. V., E-mail: marchenkov@ns.crys.ras.ru; Chukhovskii, F. N.; Blagov, A. E.

2015-03-15

The rocking curves (RCs) for MoK{sub α1} and MoK{sub α2} characteristic X-ray lines have been experimentally and theoretically studied in the nondispersive scheme of an X-ray double-crystal TPC-K diffractometer. The results of measurements and theoretical calculations of double-crystal RCs for characteristic X-rays from tubes with a molybdenum anode and different widths of slits show that a decrease in the slit width leads to an increase in the relative contribution of the MoK{sub α2}-line RC in comparison with the intensity of the tails of the MoK{sub α1}-line RC. It is shown that the second peak of the MoK{sub α2} line becomesmore » increasingly pronounced in the tail of the MoK{sub α1}-line RC with a decrease in the slit width. Two plane-parallel Si plates (input faces (110), diffraction vector h 〈220〉) were used as a monochromator crystal and a sample. The results of measuring double-crystal RCs are in good agreement with theoretical calculations.« less

Compact, Non-Pneumatic Rock-Powder Samplers

NASA Technical Reports Server (NTRS)

Sherrit, Stewart; Bar-Cohen, Yoseph; Badescu, Mircea; Bao, Xiaoqi; Chang, Zensheu; Jones, Christopher; Aldrich, Jack

2008-01-01

Tool bits that automatically collect powdered rock, permafrost, or other hard material generated in repeated hammering action have been invented. The present invention pertains to the special case in which it is desired to collect samples in powder form for analysis by x-ray diffraction and possibly other techniques. The present invention eliminates the need for both the mechanical collection equipment and the crushing chamber and the pneumatic collection equipment of prior approaches, so that it becomes possible to make the overall sample-acquisition apparatus more compact.

Characterisation of mineral deposition systems associated with rock art in the Kimberley region of northwest Australia.

PubMed

Green, Helen; Gleadow, Andrew; Finch, Damien

2017-10-01

This data article contains mineralogical and chemical data from mineral accretions sampled from rock art shelters in the Kimberley region of north west Australia. The accretions were collected both on and off pigment and engraved rock art of varying styles observed in the Kimberley with an aim of providing a thorough understanding of the formation and preservation of such materials in the context of dating [1]. This contribution includes processed powder X-ray Diffraction data, Scanning Electron Microscopy energy dispersive spectroscopy data, and Laser Ablation ICP-MS trace element mapping data.

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

NASA Astrophysics Data System (ADS)

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.

Micro X-ray diffraction analysis of thin films using grazing-exit conditions.

PubMed

Noma, T; Iida, A

1998-05-01

An X-ray diffraction technique using a hard X-ray microbeam for thin-film analysis has been developed. To optimize the spatial resolution and the surface sensitivity, the X-ray microbeam strikes the sample surface at a large glancing angle while the diffracted X-ray signal is detected with a small (grazing) exit angle. Kirkpatrick-Baez optics developed at the Photon Factory were used, in combination with a multilayer monochromator, for focusing X-rays. The focused beam size was about 10 x 10 micro m. X-ray diffraction patterns of Pd, Pt and their layered structure were measured. Using a small exit angle, the signal-to-background ratio was improved due to a shallow escape depth. Under the grazing-exit condition, the refraction effect of diffracted X-rays was observed, indicating the possibility of surface sensitivity.

High Zn Content Single-phase RS-MgZnO Suitable for Solar-blind Frequency Applications

NASA Astrophysics Data System (ADS)

Liang, H. L.; Mei, Z. X.; Liu, Z. L.; Guo, Y.; Azarov, A. Yu.; Kuznetsov, A. Yu.; Hallen, A.; Du, X. L.

2010-11-01

Single-phase rock-salt MgZnO films with high Zn content were successfully fabricated on the templates of MgO (111)/α-sapphire (0001) by radio-frequency plasma assisted molecular beam epitaxy. The influence of growth temperature on epitaxy of MgZnO alloy films was investigated by the combined studies of crystal structures, compositions, and optical properties. It is found that the incorporation of Zn atoms into the rock-salt MgZnO films is greatly enhanced at low temperature, confirmed by in-situ reflection high-energy electron diffraction observations and ex-situ X-ray diffraction characterization. Zn fraction in the single-phase rock-salt Mg0.53Zn0.47O film was determined by Rutherford backscattering spectrometry. Optical properties of the films were investigated by transmittance spectroscopy and reflectance spectroscopy, both of which demonstrate the solar-blind band gap and its dependence on Zn content.

Dehydration kinetics of talc and 10 Å phase: Consequences for subduction zone seismicity

NASA Astrophysics Data System (ADS)

Chollet, Mélanie; Daniel, Isabelle; Koga, Kenneth T.; Petitgirard, Sylvain; Morard, Guillaume

2009-06-01

The process of dehydration embrittlement is usually proposed as an explanation for the presence of intermediate-depth earthquakes in subduction zones. It assumes that the release of water by hydrous mineral breakdown is fast enough to provoke brittle failure. We performed high-pressure, high-temperature, dehydration experiments of talc and 10 Å phase coupled with in situ measurement of reaction kinetics using synchrotron X-ray diffraction. Newly developed, X-ray transparent, pressure-sealed, titanium capsule ensured a closed thermochemical environment. From isothermal kinetics data fitted to the Avrami's equation and from the texture of reaction products, we conclude that dehydration rates of these minerals are limited by diffusion. Predicted minimum rates of fluid release range from 10 - 4 to 9 × 10 - 6 m 3fluid m - 3 rock s - 1 , and are fast enough to provoke hydraulic rupture since Maxwell relaxation rate of rocks relevant of subduction zones are slower than the rate of fluid release. These rates are comparable between talc, 10 Å phase and antigorite also [Perrillat, J.-P., Daniel, I., Koga, K.T., Reynard, B., Cardon, H., Crichton, W.A., 2005. Kinetics of antigorite dehydration: a real-time X-ray diffraction study. Earth Planet. Sci. Lett. 236, 899-913]. Consequently, we suggest that the dehydration of hydrous minerals may eventually be fast enough to trigger the intermediate-depth earthquakes, and that the deepest among intermediate-depth earthquakes may actually locate the limits for dehydration of hydrous minerals in the downgoing lithosphere.

X-Ray Amorphous Phases in Terrestrial Analog Volcanic Sediments: Implications for Amorphous Phases in Gale Crater, Mars

NASA Technical Reports Server (NTRS)

Smith, R. J.; Horgan, B.; Rampe, E.; Dehouck, E.; Morris, R. V.

2017-01-01

X-ray diffraction (XRD) amorphous phases have been found as major components (approx.15-60 wt%) of all rock and soil samples measured by the CheMin XRD instrument in Gale Crater, Mars. The nature of these phases is not well understood and could be any combination of primary (e.g., glass) and secondary (e.g., allophane) phases. Amorphous phases form in abundance during surface weathering on Earth. Yet, these materials are poorly characterized, and it is not certain how properties like composition and structure change with formation environment. The presence of poorly crystalline phases can be inferred from XRD patterns by the appearance of a low angle rise (< or approx.10deg 2(theta)) or broad peaks in the background at low to moderate 2(theta) angles (amorphous humps). CheMin mineral abundances combined with bulk chemical composition measurements from the Alpha Particle X-ray Spectrometer (APXS) have been used to estimate the abundance and composition of the XRD amorphous materials in soil and rock samples on Mars. Here we apply a similar approach to a diverse suite of terrestrial samples - modern soils, glacial sediments, and paleosols - in order to determine how formation environment, climate, and diagenesis affect the abundance and composition of X-ray amorphous phases.

Study of the specific features of single-crystal boron microstructure

NASA Astrophysics Data System (ADS)

Blagov, A. E.; Vasil'ev, A. L.; Dmitriev, V. P.; Ivanova, A. G.; Kulikov, A. G.; Marchenkov, N. V.; Popov, P. A.; Presnyakov, M. Yu.; Prosekov, P. A.; Pisarevskii, Yu. V.; Targonskii, A. V.; Chernaya, T. S.; Chernyshov, D. Yu.

2017-09-01

A complex study of the structure of β-boron single crystal grown by the floating-zone method, with sizes significantly exceeding the analogs known in the literature, has been performed. The study includes X-ray diffraction analysis and X-ray diffractometry (measurement of pole figures and rocking curves), performed on both laboratory and synchrotron sources; atomic-resolution scanning transmission electron microscopy with spherical aberration correction; and energy-dispersive microanalysis. X-ray diffraction analysis using synchrotron radiation has been used to refine the β-boron structure and find impurity Si atoms. The relative variations in the unit-cell parameters a and c for the crystal bulk are found to be δ a/ a ≈ 0.4 and δ c/ c ≈ 0.1%. X-ray diffractometry has revealed that the single-crystal growth axis coincides with the [2\\bar 2013] crystallographic axis and makes an angle of 21.12° with the [0001] threefold axis. Electron microscopy data have confirmed that the sample under study is a β-boron crystal, which may contain 0.3-0.4 at % Si as an impurity. Planar defects (stacking faults and dislocations) are found. The results of additional measurements of the temperature dependence of the thermal conductivity of the crystal in the range of 50-300 K are indicative of its high structural quality.

Characterization of mineral coatings associated with a Pleistocene-Holocene rock art style: The Northern Running Figures of the East Alligator River region, western Arnhem Land, Australia.

PubMed

King, Penelope L; Troitzsch, Ulrike; Jones, Tristen

2017-02-01

This data article contains mineralogic and chemical data from mineral coatings associated with rock art from the East Alligator River region. The coatings were collected adjacent to a rock art style known as the "Northern Running Figures" for the purposes of radiocarbon dating (doi:10.1016/j.jasrep.2016.11.016; (T. Jones, V. Levchenko, P.L. King, U. Troitzsch, D. Wesley, 2017) [1]). This contribution includes raw and processed powder X-ray Diffraction data, Scanning Electron Microscopy energy dispersive spectroscopy data, and Fourier Transform infrared spectral data.

Definitive Mineralogical Analysis of Mars Analog Rocks Using the CheMin XRD/XRF Instrument

NASA Technical Reports Server (NTRS)

Blake, D. F.; Sarrazin, P.; Bish, D. L.; Feldman, S.; Chipera, S. J.; Vaniman, D. T.; Collins, S.

2004-01-01

Mineral identification is a critical component of Mars Astrobiological missions. Chemical or elemental data alone are not definitive because a single elemental or chemical composition or even a single bonding type can represent a range of substances or mineral assemblages. Minerals are defined as unique structural and compositional phases that occur naturally. There are about 15,000 minerals that have been described on Earth, all uniquely identifiable via diffraction methods. There are likely many minerals yet undiscovered on Earth, and likewise on Mars. If an unknown phase is identified on Mars, it can be fully characterized by structural (X-ray Diffraction, XRD) and elemental analysis (X-ray Fluorescence, XRF) without recourse to other data because XRD relies on the principles of atomic arrangement for its determinations. XRD is the principal means of identification and characterization of minerals on Earth.

Synchrotron x-ray diffraction studies of the structural properties of electrode materials in operating battery cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Thurston, T.R.; Jisrawi, N.M.; Mukerjee, S.

Hard x rays from a synchrotron source were utilized in diffraction experiments which probed the bulk of electrode materials while they were operating {ital in} {ital situ} in battery cells. Two technologically relevant electrode materials were examined; an {ital AB}{sub 2}-type anode in a nickel{endash}metal{endash}hydride cell and a LiMn{sub 2}O{sub 4} cathode in a Li-ion {open_quote}{open_quote}rocking chair{close_quote}{close_quote} cell. Structural features such as lattice expansions and contractions, phase transitions, and the formation of multiple phases were easily observed as either hydrogen or lithium was electrochemically intercalated in and out of the electrode materials. The relevance of this technique for future studiesmore » of battery electrode materials is discussed. {copyright} {ital 1996 American Institute of Physics.}« less

Flux growth of high-quality CoFe 2O 4 single crystals and their characterization

NASA Astrophysics Data System (ADS)

Wang, W. H.; Ren, X.

2006-04-01

We report the growth of high-quality CoFe 2O 4 single crystals using a borax flux method. The crystals were characterized by powder X-ray diffraction, electron probe microanalysis and Raman spectroscopy. We found the crystals are flux-free and highly homogeneous in composition. X-ray rocking curves of the CoFe 2O 4 single crystals showed a full-width at half-maximum of 0.15°. The saturation magnetization of the CoFe 2O 4 single crystals was measured to be 90 emu/g or equivalently 3.65 μ B/f.u. at 5 K.

Astrobiological Significance of Definitive Mineralogical Analysis of Martian Surface Samples Using the CheMin XRD/XRF Instrument

NASA Technical Reports Server (NTRS)

Feldman, S. M.; Blake, D. F.; Sarrazin, P.; Bish, D. L.; Chipera, S. J.; Vaniman, D. T.; Collins, S.

2004-01-01

The search for evidence of habitability, or of extant or extinct life on Mars, will initially be a search for evidence of past or present conditions supportive of life. The three key requirements for the emergence of life are thought to be liquid water; a suitable energy source; and chemical building blocks. CheMin is a miniaturized XRD/XRF (X-Ray diffraction / X-ray fluorescence) instrument which has been developed for definitive mineralogic analysis of soils and rocks on the Martian surface. The CheMin instrument can provide information that is highly relevant to each of these habitability requirements as summarized below.

X-ray diffraction from shock-loaded polycrystals.

PubMed

Swift, Damian C

2008-01-01

X-ray diffraction was demonstrated from shock-compressed polycrystalline metals on nanosecond time scales. Laser ablation was used to induce shock waves in polycrystalline foils of Be, 25-125 microm thick. A second laser pulse was used to generate a plasma x-ray source by irradiation of a Ti foil. The x-ray source was collimated to produce a beam of controllable diameter, which was directed at the Be sample. X-rays were diffracted from the sample, and detected using films and x-ray streak cameras. The diffraction angle was observed to change with shock pressure. The diffraction angles were consistent with the uniaxial (elastic) and isotropic (plastic) compressions expected for the loading conditions used. Polycrystalline diffraction will be used to measure the response of the crystal lattice to high shock pressures and through phase changes.

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

Maddox, B. R., E-mail: maddox3@llnl.gov; Akin, M. C., E-mail: akin1@llnl.gov; Teruya, A.

2016-08-15

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

[X-ray diffraction (XRD) and near infrared spectrum (NIR) analysis of the soil overlying the Bairendaba deposit of the Inner Mongolia Grassland].

PubMed

Luo, Song-ying; Cao, Jian-jin; Wu, Zheng-quan

2014-08-01

The soil samples uniformly overlying the Bairendaba deposit of the Inner Mongolia grassland were collected, and ana- lyzed with X-ray diffraction (XRD) and near infrared spectrum (NIR), for exploring the origins of the soil from the, grassland mining area and the relationship with the underground rock. The results show that the samp]s consist of quartz, graphite, carbonate, hornblende, mica, chlorite, montmorillonite, illite, berlinite, diaspore, azurite, hen tite, etc. These indicate that the soil samples were not only from the weathering products of the surface rock, but also from the underground rock mass and the alteration of the wall rock. The azurite and the hematite contained in the soil, mainly coming from the oxidation zone of the orebodies, can be used as the prospecting marks. The alteration mineral assemblage is mainly chlorite-illite-montmorillonite and it experienced the alteration process of potassic alteration-->silicification-->carbonatization-->silk greisenization-->clayization. Also, the wall rock alteration and the physical weathering processes can be accurately restored by analyzing the combination of the alteration minerals, which can provide important reference information for the deep ore prospecting and the ore deposit genesis study, improving the rate of the prospecting. The XRD and NIR with the characteristics of the economy and quickness can be used for the identification of mineral composition of soil, and in the study of mineral and mineral deposits. Especially, NIR has its unique superiority, that is, its sample request is low, and it can analyze a batch of samples quickly. With the development of INR, it will be more and more widely applied in geological field, and can play an important role in the ore exploration.

X-Ray Diffraction Apparatus

NASA Technical Reports Server (NTRS)

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

1996-01-01

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

Use of variations in unit cell length, reflectance and hardness for determining the origin of Fe disulphides in sedimentary rocks

NASA Astrophysics Data System (ADS)

Dill, H. G.; Eberhard, E.; Hartmann, B.

1997-01-01

Fe disulphides are common opaque accessories in sedimentary rocks. Both marcasite and pyrite may shed some light on the depositional environment and help determine the diagenesis of their host rocks. Quantitative ore microscopy (reflectance measurements, Vickers hardness numbers) and X-ray diffraction methods, supplemented with scanning electron microscopy and chemical analyses, were applied to pyrite (and some marcasite) hosted by sedimentary rocks spanning the interval from the Devonian to the Pliocene, and formed in various marine and continental environments. Quantitative ore microscopy of pyrites of sedimentary origin does not seem to be an efficient tool for analyzing the environment owing to the inhomogeneous nature of sulphide aggregates when viewed under the ore microscope, and the variable amounts of minor elements (e.g., As, Ni, and Co) that control the reflectance values (RV) and Vickers hardness numbers (VHN) of the host sulphides. However, such parameters as crystal habit and unit cell length of pyrite, which correlate with FeS x, are useful for environmental analysis. The redox conditions and the presence of organic remains during formation are the main factors determining these crystallographic parameters. Differences in these parameters from those of pure, ideal FeS 2 can be related to substitution of, e.g., wustite in the pyrite lattice, reflecting moderate oxidation (i.e. in the microenvironment). As far as crystal habit and length of the cell edge are concerned, late stage diagenesis is obviously less important than the microenvironment attending initial formation. The environment of deposition (i.e. the macroenvironment) of pyrite-bearing rocks has no influence on the crystal morphology or the length of the unit cell of Fe disulphide. X-ray diffraction measurements demonstrate that this method provides useful evidence on the microenvironment of sulphide precipitation around a single, equant pyrite, as well as around pyritized fossils.

Experimentally Shock-loaded Anhydrite: Unit-Cell Dimensions, Microstrain and Domain Size from X-Ray Diffraction

NASA Technical Reports Server (NTRS)

Skala, R.; Hoerz, F.

2003-01-01

Cretaceous Tertiary (K/T) boundary is traditionally associated with one of the most dramatic mass extinctions in the Earth history. A number of killing mechanisms have been suggested to contribute to the widespread extinctions of Cretaceous biota at this boundary, including severe, global deterioration of the atmosphere and hydrosphere from the shock-induced release of CO2 and SO(x) from carbonate- and sulfate-bearing target rocks, respectively. Recently carried out calculations revealed that the global warming caused by CO2 release was considerably less important than the cooling due to SO(x) gases release during the Chicxulub impact event. Considering apparent potential importance of the response of sulfates to the shock metamorphism, relative lack of the data on shock behavior of sulfates as well as some general difficulties encountered during thermodynamic modeling of the shock-induced CO2 loss from carbonates we subjected anhydrite to a series of shock experiments designed for complete recovery of the shocked material. We report here on the detail X-ray diffraction analysis of seven samples that were subjected to experimental shock-loading from 10 to 65 GPa.

Mössbauer study of Brazilian soapstone

NASA Astrophysics Data System (ADS)

Gonçalves, M. A.; de Jesus Filho, M. F.; Garg, V. K.

1991-11-01

Steatite mineral rocks, soapstone, have been studied by X-ray diffraction, optical microscopic analysis (modal analysis), electron probe micro analysis and Mössbauer spectroscopy for characterization, mineral percentages and chemical composition. Mössbauer spectra show both, magnetic interactions corresponding to magnetite and doublets corresponding to talc. chlorite, dolomite and tremolite. The temperature dependence of the quadrupole splitting in dolomite has been explained in terms of crystal field interaction.

Mineralogy of Drill Cuttings Beowawe, Dixie Valley and Roosevelt Hot Springs

DOE Data Explorer

Simmons, Stuart

2017-01-25

Mineralogical, lithological, and geospatial data of drill cuttings from exploration production wells in Beowawe, Dixie Valley and Roosvelt Hot Springs. These data support whole rock analyses for major, minor and critical elements to assess critical metals in produced fluids from Nevada and Utah geothermal fields. The samples were analyzed by x-ray diffraction (legacy data) and then checked by thin section analysis.

Real-time X-ray Diffraction: Applications to Materials Characterization

NASA Technical Reports Server (NTRS)

Rosemeier, R. G.

1984-01-01

With the high speed growth of materials it becomes necessary to develop measuring systems which also have the capabilities of characterizing these materials at high speeds. One of the conventional techniques of characterizing materials was X-ray diffraction. Film, which is the oldest method of recording the X-ray diffraction phenomenon, is not quite adequate in most circumstances to record fast changing events. Even though conventional proportional counters and scintillation counters can provide the speed necessary to record these changing events, they lack the ability to provide image information which may be important in some types of experiment or production arrangements. A selected number of novel applications of using X-ray diffraction to characterize materials in real-time are discussed. Also, device characteristics of some X-ray intensifiers useful in instantaneous X-ray diffraction applications briefly presented. Real-time X-ray diffraction experiments with the incorporation of image X-ray intensification add a new dimension in the characterization of materials. The uses of real-time image intensification in laboratory and production arrangements are quite unlimited and their application depends more upon the ingenuity of the scientist or engineer.

Radiation damage free ghost diffraction with atomic resolution

DOE PAGES

Li, Zheng; Medvedev, Nikita; Chapman, Henry N.; ...

2017-12-21

The x-ray free electron lasers can enable diffractive structural determination of protein nanocrystals and single molecules that are too small and radiation-sensitive for conventional x-ray diffraction. However the electronic form factor may be modified during the ultrashort x-ray pulse due to photoionization and electron cascade caused by the intense x-ray pulse. For general x-ray imaging techniques, the minimization of the effects of radiation damage is of major concern to ensure reliable reconstruction of molecular structure. Here in this paper, we show that radiation damage free diffraction can be achieved with atomic spatial resolution by using x-ray parametric down-conversion and ghostmore » diffraction with entangled photons of x-ray and optical frequencies. We show that the formation of the diffraction patterns satisfies a condition analogous to the Bragg equation, with a resolution that can be as fine as the crystal lattice length scale of several Ångstrom. Since the samples are illuminated by low energy optical photons, they can be free of radiation damage.« less

Radiation damage free ghost diffraction with atomic resolution

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Zheng; Medvedev, Nikita; Chapman, Henry N.

The x-ray free electron lasers can enable diffractive structural determination of protein nanocrystals and single molecules that are too small and radiation-sensitive for conventional x-ray diffraction. However the electronic form factor may be modified during the ultrashort x-ray pulse due to photoionization and electron cascade caused by the intense x-ray pulse. For general x-ray imaging techniques, the minimization of the effects of radiation damage is of major concern to ensure reliable reconstruction of molecular structure. Here in this paper, we show that radiation damage free diffraction can be achieved with atomic spatial resolution by using x-ray parametric down-conversion and ghostmore » diffraction with entangled photons of x-ray and optical frequencies. We show that the formation of the diffraction patterns satisfies a condition analogous to the Bragg equation, with a resolution that can be as fine as the crystal lattice length scale of several Ångstrom. Since the samples are illuminated by low energy optical photons, they can be free of radiation damage.« less

Synchrotron Radiation X-ray Diffraction Techniques Applied to Insect Flight Muscle.

PubMed

Iwamoto, Hiroyuki

2018-06-13

X-ray fiber diffraction is a powerful tool used for investigating the molecular structure of muscle and its dynamics during contraction. This technique has been successfully applied not only to skeletal and cardiac muscles of vertebrates but also to insect flight muscle. Generally, insect flight muscle has a highly ordered structure and is often capable of high-frequency oscillations. The X-ray diffraction studies on muscle have been accelerated by the advent of 3rd-generation synchrotron radiation facilities, which can generate brilliant and highly oriented X-ray beams. This review focuses on some of the novel experiments done on insect flight muscle by using synchrotron radiation X-rays. These include diffraction recordings from single myofibrils within a flight muscle fiber by using X-ray microbeams and high-speed diffraction recordings from the flight muscle during the wing-beat of live insects. These experiments have provided information about the molecular structure and dynamic function of flight muscle in unprecedented detail. Future directions of X-ray diffraction studies on muscle are also discussed.

Characterization and obtainment of phosphate rock concentrates of Turmequé, Boyacá

NASA Astrophysics Data System (ADS)

Zanguña, S. Quijano; Lozano Gómez, L. F.; Pineda Triana, Y.

2017-12-01

The work focuses on the use and exploitation of the mineral concentrates from phosphate rock (PR) coming from mines with a low percentage of phosphorus. The procedure was based on the collection of a source of phosphate rock from the department of Boyacá (municipality of Turmequé), using a randomized design with three replications. The samples were initially milled and sifted using meshes between 140 and 200 US standard, homogenizing them and improving the process of solubility of the phosphorus in the soil. We conduced Z-potential tests, which show that by performing a prior wash on the mineral and maintaining certain concentrations and pH defined, better results are achieved in terms of the buoyancy of the particles in the flotation process. The results obtained from the microflotation tests; both direct and inverse, and the results of chemical composition, with X-Ray Fluorescence (XRF) and X-Ray Diffraction (XRD), before and after the microflotation process, were carried out to obtain of commercial laws grade phosphate rock concentrate, confirm that the protocol used increases by 9% the value of total phosphorus in the collected sample. These concentrates from phosphate rock, could be used in the future for the attainment of simple superphosphate (SSP), with the help of sulphuric acid and ammonium thiosulphate mixtures.

Combining experiment and optical simulation in coherent X-ray nanobeam characterization of Si/SiGe semiconductor heterostructures

DOE PAGES

Tilka, J. A.; Park, J.; Ahn, Y.; ...

2016-07-06

Here, the highly coherent and tightly focused x-ray beams produced by hard x-ray light sources enable the nanoscale characterization of the structure of electronic materials but are accompanied by significant challenges in the interpretation of diffraction and scattering patterns. X-ray nanobeams exhibit optical coherence combined with a large angular divergence introduced by the x-ray focusing optics. The scattering of nanofocused x-ray beams from intricate semiconductor heterostructures produces a complex distribution of scattered intensity. We report here an extension of coherent xray optical simulations of convergent x-ray beam diffraction patterns to arbitrary x-ray incident angles to allow the nanobeam diffraction patternsmore » of complex heterostructures to be simulated faithfully. These methods are used to extract the misorientation of lattice planes and the strain of individual layers from synchrotron x-ray nanobeam diffraction patterns of Si/SiGe heterostructures relevant to applications in quantum electronic devices. The systematic interpretation of nanobeam diffraction patterns from semiconductor heterostructures presents a new opportunity in characterizing and ultimately designing electronic materials.« less

Fabrication and testing of a newly designed slit system for depth-resolved X-ray diffraction measurements

DOE PAGES

Sinsheimer, John; Bouet, Nathalie; Ghose, Sanjit; ...

2016-10-06

A new system of slits called `spiderweb slits' have been developed for depth-resolved powder or polycrystalline X-ray diffraction measurements. The slits act on diffracted X-rays to select a particular gauge volume of sample, while absorbing diffracted X-rays from outside of this volume. Although the slit geometry is to some extent similar to that of previously developed conical slits or spiral slits, this new design has advantages over the previous ones in use for complex heterogeneous materials and in situ and operando diffraction measurements. For example, the slits can measure a majority of any diffraction cone for any polycrystalline material, overmore » a continuous range of diffraction angles, and work for X-ray energies of tens to hundreds of kiloelectronvolts. In addition, the design is generated and optimized using ray-tracing simulations, and fabricated through laser micromachining. The first prototype was successfully tested at the X17A beamline at the National Synchrotron Light Source, and shows similar performance to simulations, demonstrating gauge volume selection for standard powders, for all diffraction peaks over angles of 2–10°. A similar, but improved, design will be implemented at the X-ray Powder Diffraction beamline at the National Synchrotron Light Source II.« less

Protein Crystal Movements and Fluid Flows During Microgravity Growth

NASA Technical Reports Server (NTRS)

Boggon, Titus J.; Chayen, Naomi E.; Snell, Edward H.; Dong, Jun; Lautenschlager, Peter; Potthast, Lothar; Siddons, D. Peter; Stojanoff, Vivian; Gordon, Elspeth; Thompson, Andrew W.;

Dynamical scattering in coherent hard x-ray nanobeam Bragg diffraction

NASA Astrophysics Data System (ADS)

Pateras, A.; Park, J.; Ahn, Y.; Tilka, J. A.; Holt, M. V.; Kim, H.; Mawst, L. J.; Evans, P. G.

2018-06-01

Unique intensity features arising from dynamical diffraction arise in coherent x-ray nanobeam diffraction patterns of crystals having thicknesses larger than the x-ray extinction depth or exhibiting combinations of nanoscale and mesoscale features. We demonstrate that dynamical scattering effects can be accurately predicted using an optical model combined with the Darwin theory of dynamical x-ray diffraction. The model includes the highly divergent coherent x-ray nanobeams produced by Fresnel zone plate focusing optics and accounts for primary extinction, multiple scattering, and absorption. The simulation accurately reproduces the dynamical scattering features of experimental diffraction patterns acquired from a GaAs/AlGaAs epitaxial heterostructure on a GaAs (001) substrate.

Coherent x-ray diffraction imaging with nanofocused illumination.

PubMed

Schroer, C G; Boye, P; Feldkamp, J M; Patommel, J; Schropp, A; Schwab, A; Stephan, S; Burghammer, M; Schöder, S; Riekel, C

2008-08-29

Coherent x-ray diffraction imaging is an x-ray microscopy technique with the potential of reaching spatial resolutions well beyond the diffraction limits of x-ray microscopes based on optics. However, the available coherent dose at modern x-ray sources is limited, setting practical bounds on the spatial resolution of the technique. By focusing the available coherent flux onto the sample, the spatial resolution can be improved for radiation-hard specimens. A small gold particle (size <100 nm) was illuminated with a hard x-ray nanobeam (E=15.25 keV, beam dimensions approximately 100 x 100 nm2) and is reconstructed from its coherent diffraction pattern. A resolution of about 5 nm is achieved in 600 s exposure time.

DynAMITe: a prototype large area CMOS APS for breast cancer diagnosis using x-ray diffraction measurements

NASA Astrophysics Data System (ADS)

Konstantinidis, A.; Anaxagoras, T.; Esposito, M.; Allinson, N.; Speller, R.

2012-03-01

X-ray diffraction studies are used to identify specific materials. Several laboratory-based x-ray diffraction studies were made for breast cancer diagnosis. Ideally a large area, low noise, linear and wide dynamic range digital x-ray detector is required to perform x-ray diffraction measurements. Recently, digital detectors based on Complementary Metal-Oxide- Semiconductor (CMOS) Active Pixel Sensor (APS) technology have been used in x-ray diffraction studies. Two APS detectors, namely Vanilla and Large Area Sensor (LAS), were developed by the Multidimensional Integrated Intelligent Imaging (MI-3) consortium to cover a range of scientific applications including x-ray diffraction. The MI-3 Plus consortium developed a novel large area APS, named as Dynamically Adjustable Medical Imaging Technology (DynAMITe), to combine the key characteristics of Vanilla and LAS with a number of extra features. The active area (12.8 × 13.1 cm2) of DynaMITe offers the ability of angle dispersive x-ray diffraction (ADXRD). The current study demonstrates the feasibility of using DynaMITe for breast cancer diagnosis by identifying six breast-equivalent plastics. Further work will be done to optimize the system in order to perform ADXRD for identification of suspicious areas of breast tissue following a conventional mammogram taken with the same sensor.

Resolution enhancement in coherent x-ray diffraction imaging by overcoming instrumental noise.

PubMed

Kim, Chan; Kim, Yoonhee; Song, Changyong; Kim, Sang Soo; Kim, Sunam; Kang, Hyon Chol; Hwu, Yeukuang; Tsuei, Ku-Ding; Liang, Keng San; Noh, Do Young

2014-11-17

We report that reference objects, strong scatterers neighboring weak phase objects, enhance the phase retrieval and spatial resolution in coherent x-ray diffraction imaging (CDI). A CDI experiment with Au nano-particles exhibited that the reference objects amplified the signal-to-noise ratio in the diffraction intensity at large diffraction angles, which significantly enhanced the image resolution. The interference between the diffracted x-ray from reference objects and a specimen also improved the retrieval of the phase of the diffraction signal. The enhancement was applied to image NiO nano-particles and a mitochondrion and confirmed in a simulation with a bacteria phantom. We expect that the proposed method will be of great help in imaging weakly scattering soft matters using coherent x-ray sources including x-ray free electron lasers.

Microbial Fe biomineralization in mafic and ultramafic rocks

NASA Astrophysics Data System (ADS)

Templeton, A. S.; Mayhew, L.; McCollom, T.; Trainor, T.

2011-12-01

Fluid-filled microfractures within mafic and ultramafic rocks, such as basalt and peridotite, may be one of the most ubiquitous microbial habitats on the modern and ancient earth. In seafloor and subseafloor systems, one of the dominant energy sources is the oxidation of Fe by numerous potential oxidants under aerobic to anaerobic conditions. In particular, the oxidation of Fe may be directly catalyzed by microbial organisms, or result in the production of molecular hydrogen which can then fuel diverse lithotrophic metabolisms. However, it remains challenging to identify the dominant metabolic activities and unravel the microscale biogeochemical processes occuring within such rock-hosted systems. We are investigating the mechanisms of solid-state Fe-oxidation and biomineralization in basalt, olivine, pyroxenes and basalts, in the presence and absence of microbial organisms that can thrive across the full stability range of water. In this talk we will present synchrotron-based x-ray scattering and spectroscopic analyses of Fe speciation within secondary minerals formed during microbially-mediated vs. abiotic water-rock interactions. Determining the valence state and mineralogy of Fe-bearing phases is critical for determining the water-rock reaction pathways and identifying potential biominerals that may form; therefore, we will highlight new approaches for identifying key Fe transformations within complex geological media. In addition, many of our experimental studies involve the growth of lithotrophic biofilms on well-characterized mineral surfaces in order to determine the chemistry of the microbe-mineral interface during progressive electron-transfer reactions. By coupling x-ray spectroscopy, x-ray diffraction, and electron-microscopy measurements, we will also contrast the evolution of mineral surfaces that undergo microbially-mediated oxidative alteration against minerals surfaces that produce H2 to sustain anaerobic microbial communities.

Fabrication and testing of a newly designed slit system for depth-resolved X-ray diffraction measurements

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sinsheimer, John; Bouet, Nathalie; Ghose, Sanjit

2016-10-06

A new system of slits called `spiderweb slits' have been developed for depth-resolved powder or polycrystalline X-ray diffraction measurements. The slits act on diffracted X-rays to select a particular gauge volume of sample, while absorbing diffracted X-rays from outside of this volume. Although the slit geometry is to some extent similar to that of previously developed conical slits or spiral slits, this new design has advantages over the previous ones in use for complex heterogeneous materials andin situandoperandodiffraction measurements. For example, the slits can measure a majority of any diffraction cone for any polycrystalline material, over a continuous range ofmore » diffraction angles, and work for X-ray energies of tens to hundreds of kiloelectronvolts. The design is generated and optimized using ray-tracing simulations, and fabricated through laser micromachining. The first prototype was successfully tested at the X17A beamline at the National Synchrotron Light Source, and shows similar performance to simulations, demonstrating gauge volume selection for standard powders, for all diffraction peaks over angles of 2–10°. A similar, but improved, design will be implemented at the X-ray Powder Diffraction beamline at the National Synchrotron Light Source II.« less

Local terahertz field enhancement for time-resolved x-ray diffraction

DOE PAGES

Kozina, M.; Pancaldi, M.; Bernhard, C.; ...

2017-02-20

We report local field strength enhancement of single-cycle terahertz (THz) pulses in an ultrafast time-resolved x-ray diffraction experiment. We show that patterning the sample with gold microstructures increases the THz field without changing the THz pulse shape or drastically affecting the quality of the x-ray diffraction pattern. Lastly, we find a five-fold increase in THz-induced x-ray diffraction intensity change in the presence of microstructures on a SrTiO 3 thin-film sample.

Local terahertz field enhancement for time-resolved x-ray diffraction

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kozina, M.; Pancaldi, M.; Bernhard, C.

We report local field strength enhancement of single-cycle terahertz (THz) pulses in an ultrafast time-resolved x-ray diffraction experiment. We show that patterning the sample with gold microstructures increases the THz field without changing the THz pulse shape or drastically affecting the quality of the x-ray diffraction pattern. Lastly, we find a five-fold increase in THz-induced x-ray diffraction intensity change in the presence of microstructures on a SrTiO 3 thin-film sample.

Micro-x-ray fluorescence, micro-x-ray absorption spectroscopy, and micro-x-ray diffraction investigation of lead speciation after the addition of different phosphorus amendments to a smelter-contaminated soil.

PubMed

Baker, Lucas R; Pierzynski, Gary M; Hettiarachchi, Ganga M; Scheckel, Kirk G; Newville, Matthew

2014-03-01

The stabilization of Pb on additions of P to contaminated soils and mine spoil materials has been well documented. It is clear from the literature that different P sources result in different efficacies of Pb stabilization in the same contaminated material. We hypothesized that the differences in the efficacy of Pb stabilization in contaminated soils on fluid or granular P amendment addition is due to different P reaction processes in and around fertilizer granules and fluid droplets. We used a combination of several synchrotron-based techniques (i.e., spatially resolved micro-X-ray fluorescence, micro-X-ray absorption near-edge structure spectroscopy, and micro-X-ray diffraction) to speciate Pb at two incubation times in a smelter-contaminated soil on addition of several fluid and granular P amendments. The results indicated that the Pb phosphate mineral plumbogummite was an intermediate phase of pyromorphite formation. Additionally, all fluid and granular P sources were able to induce Pb phosphate formation, but fluid phosphoric acid (PA) was the most effective with time and distance from the treatment. Granular phosphate rock and triple super phosphate (TSP) amendments reacted to generate Pb phosphate minerals, with TSP being more effective at greater distances from the point of application. As a result, PA and TSP were the most effective P amendments at inducing Pb phosphate formation, but caution needs to be exercised when adding large amounts of soluble P to the environment. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Thermal x-ray diffraction and near-field phase contrast imaging

NASA Astrophysics Data System (ADS)

Li, Zheng; Classen, Anton; Peng, Tao; Medvedev, Nikita; Wang, Fenglin; Chapman, Henry N.; Shih, Yanhua

2017-10-01

Using higher-order coherence of thermal light sources, the resolution power of standard x-ray imaging techniques can be enhanced. In this work, we applied the higher-order measurement to far-field x-ray diffraction and near-field phase contrast imaging (PCI), in order to achieve superresolution in x-ray diffraction and obtain enhanced intensity contrast in PCI. The cost of implementing such schemes is minimal compared to the methods that achieve similar effects by using entangled x-ray photon pairs.

Thermal x-ray diffraction and near-field phase contrast imaging

DOE PAGES

Li, Zheng; Classen, Anton; Peng, Tao; ...

2017-12-27

Using higher-order coherence of thermal light sources, the resolution power of standard x-ray imaging techniques can be enhanced. Here in this work, we applied the higher-order measurement to far-field x-ray diffraction and near-field phase contrast imaging (PCI), in order to achieve superresolution in x-ray diffraction and obtain enhanced intensity contrast in PCI. The cost of implementing such schemes is minimal compared to the methods that achieve similar effects by using entangled x-ray photon pairs.

Reuse of ornamental rock-cutting waste in aluminous porcelain.

PubMed

Silva, M A; Paes, H R; Holanda, J N F

2011-03-01

Large amounts of solid wastes are discarded in the ornamental rocks industry. This work investigates the incorporation of ornamental rock-cutting waste as a raw material into an aluminous porcelain body, replacing natural feldspar material by up to 35 wt.%. Formulations containing rock-cutting waste were pressed and sintered at 1350 °C. The porcelain pieces were tested to determine their properties (linear shrinkage, water absorption, apparent density, mechanical strength, and electrical resistivity). Development of the microstructure was followed by scanning electron microscopy (SEM) and X-ray diffraction (XRD) analyses. The results showed that ornamental rock-cutting waste could be used in aluminous porcelains, in the range up to 10 wt.%, as a partial replacement for traditional flux material, resulting in a valid route for management of this abundant waste. Copyright © 2010 Elsevier Ltd. All rights reserved.

Assessing the Role of Anhydrite in the KT Mass Extinction: Hints from Shock-loading Experiments

NASA Technical Reports Server (NTRS)

Skala, R.; Lnagenhorst, F.; Hoerz, F.

2004-01-01

Various killing mechanisms have been suggested to contribute to the mass extinctions at the KT boundary, including severe, global deterioration of the atmosphere and hydrosphere due to SO(x) released from heavily shocked, sulfate-bearing target rocks. The devolatilization of anhydrite is predominantly inferred from thermodynamic considerations and lacks experimental confirmation. To date, the experimentally determined shock behavior of anhydrite is limited to solid-state effects employing X-ray diffraction methods. The present report employs additional methods to characterize experimentally shocked anhydrite.

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

DOEpatents

Sommargren, Gary E.; Weaver, H. Joseph

1991-01-01

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

Evaluation of Rock Powdering Methods to Obtain Fine-grained Samples for CHEMIN, a Combined XRD/XRF Instrument

NASA Technical Reports Server (NTRS)

Chipera, S. J.; Vaniman, D. T.; Bish, D. L.; Sarrazin, P.; Feldman, S.; Blake, D. F.; Bearman, G.; Bar-Cohen, Y.

2004-01-01

A miniature XRD/XRF (X-ray diffraction / X-ray fluorescence) instrument, CHEMIN, is currently being developed for definitive mineralogic analysis of soils and rocks on Mars. One of the technical issues that must be addressed to enable remote XRD analysis is how best to obtain a representative sample powder for analysis. For powder XRD analyses, it is beneficial to have a fine-grained sample to reduce preferred orientation effects and to provide a statistically significant number of crystallites to the X-ray beam. Although a two-dimensional detector as used in the CHEMIN instrument will produce good results even with poorly prepared powder, the quality of the data will improve and the time required for data collection will be reduced if the sample is fine-grained and randomly oriented. A variety of methods have been proposed for XRD sample preparation. Chipera et al. presented grain size distributions and XRD results from powders generated with an Ultrasonic/Sonic Driller/Corer (USDC) currently being developed at JPL. The USDC was shown to be an effective instrument for sampling rock to produce powder suitable for XRD. In this paper, we compare powder prepared using the USDC with powder obtained with a miniaturized rock crusher developed at JPL and with powder obtained with a rotary tungsten carbide bit to powders obtained from a laboratory bench-scale Retsch mill (provides benchmark mineralogical data). These comparisons will allow assessment of the suitability of these methods for analysis by an XRD/XRF instrument such as CHEMIN.

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

DOE PAGES

Huang, Xiaojing; Nelson, Johanna; Kirz, Janos; ...

2009-11-01

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

Ae2Sb2X4F2 (Ae = Sr, Ba): new members of the homologous series Ae2M(1+n)X(3+n)F2 designed from rock salt and fluorite 2D building blocks.

PubMed

Kabbour, Houria; Cario, Laurent

2006-03-20

We have designed new compounds within the homologous series Ae2F2M(1+n)X(3+n) (Ae = Sr, Ba; M = main group metal; n = integer) built up from the stacking of 2D building blocks of rock salt and fluorite types. By incrementally increasing the size of the rock salt 2D building blocks, we have obtained two new n = 1 members of this homologous series, namely, Sr2F2Sb2Se4 and Ba2F2Sb2Se4. We then succeeded in synthesizing these compounds using a high-temperature ceramic method. The structure refinements from the powder or single-crystal X-ray diffraction data confirmed presence of the expected alternating stacking of fluorite [Ae2F2] (Ae = Sr, Ba) and rock salt [Sb2Se4] 2D building blocks. However the Ba derivative shows a strong distortion of the [Sb2Se4] block and a concomitant change of the Sb atom coordination likely related to the lone-pair activity.

Application of focused-beam flat-sample method to synchrotron powder X-ray diffraction with anomalous scattering effect

NASA Astrophysics Data System (ADS)

Tanaka, M.; Katsuya, Y.; Matsushita, Y.

2013-03-01

The focused-beam flat-sample method (FFM), which is a method for high-resolution and rapid synchrotron X-ray powder diffraction measurements by combination of beam focusing optics, a flat shape sample and an area detector, was applied for diffraction experiments with anomalous scattering effect. The advantages of FFM for anomalous diffraction were absorption correction without approximation, rapid data collection by an area detector and good signal-to-noise ratio data by focusing optics. In the X-ray diffraction experiments of CoFe2O4 and Fe3O4 (By FFM) using X-rays near the Fe K absorption edge, the anomalous scattering effect between Fe/Co or Fe2+/Fe3+ can be clearly detected, due to the change of diffraction intensity. The change of observed diffraction intensity as the incident X-ray energy was consistent with the calculation. The FFM is expected to be a method for anomalous powder diffraction.

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

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

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 absorptionmore » 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.« less

Studies on synthesis, growth, structural, thermal, linear and nonlinear optical properties of organic picolinium maleate single crystals.

PubMed

Pandi, P; Peramaiyan, G; Sudhahar, S; Chakkaravarthi, G; Mohan Kumar, R; Bhagavannarayana, G; Jayavel, R

2012-12-01

Picolinium maleate (PM), an organic material has been synthesised and single crystals were grown by slow evaporation technique. The structure of the grown crystal was elucidated by using single crystal X-ray diffraction analysis. PM crystal belongs to the monoclinic crystallographic system with space group P2(1)/c. The crystalline perfection of the grown crystals was analyzed by high-resolution X-ray diffraction rocking curve measurements. The presence of functional groups in PM was identified by FTIR and FT-NMR spectral analyses. Thermal behaviour and stability of picolinium maleate were studied by TGA/DTA analyses. UV-Vis spectral studies reveal that PM crystals are transparent in the wavelength region 327-1100 nm. The laser damage threshold value of PM crystal was found to be 4.3 GW/cm(2) using Nd:YAG laser. The Kurtz and Perry powder second harmonic generation technique confirms the nonlinear optical property of the grown crystal. Copyright © 2012 Elsevier B.V. All rights reserved.

Real-Time Reciprocal Space Mapping of Nano-Islands Induced by Quantum Confinement

NASA Astrophysics Data System (ADS)

Hong, Hawoong; Gray, Aaron; Chiang, T.-C.

2011-01-01

The effects of quantum confinement have been observed pronouncedly in the island morphology of Pb thin films. The evolution of these nano-islands on Si (111)-(7 × 7) and sapphire (001) surfaces has been studied with a new X-ray diffraction method. A charge-coupled device (CCD) camera was used to collect two- and three-dimensional (2-D and 3-D, respectively) maps of the surface X-ray diffraction in real time. Large ranges of the reflectivity curves, with rocking curves at every point on the reflectivity curves, could be measured continuously in a relatively short amount of time. The abundance of information from 2-D k-space maps reveals clear changes in the growth modes of these thin Pb films. With the 3-D extension of this method, it was possible to observe the ordering of the islands. The islands maintain a nearly uniform interisland distance but lack any angular correlation. The interisland ordering is correlated well with the development of "magic" island heights caused by quantum confinement.

Controllable synthesis of protein-conjugated lead sulfide nanocubes by using bovine hemoglobin as a capping agent

NASA Astrophysics Data System (ADS)

Yang, Guangrui; Qin, Dezhi; Zhang, Li

2014-06-01

A simple, convenient, and controllable strategy was reported in this contribution for protein-assisted synthesis BHb-conjugated PbS nanocubes. Powder X-ray diffraction, energy disperse X-ray spectroscopy, transmission electron microscopy, high-resolution transmission electron microscopy, and selected-area electron diffraction characterizations were used to determine the structure and morphology of BHb-conjugated PbS nanocubes. The prepared PbS nanocrystals with cubic rock salt structure were uniform and monodispersed with homogeneous size around 12 nm. The results of Fourier transform infrared and circular dichroism assay proved that Pb2+/PbS had coordination interaction with functional groups of BHb besides physical-binding effect, and the secondary structure of protein significantly changed with this interaction. Thermogravimetric analysis results confirmed the existence of BHb in PbS nanocrystals and indicated that the conjugate bonds existed between PbS and BHb. A clear perspective was shown here that special nanostructure could be created by using proteins as a mediating template at the inorganic-organic interface.

Dynamical effects in Bragg coherent x-ray diffraction imaging of finite crystals

NASA Astrophysics Data System (ADS)

Shabalin, A. G.; Yefanov, O. M.; Nosik, V. L.; Bushuev, V. A.; Vartanyants, I. A.

2017-08-01

We present simulations of Bragg coherent x-ray diffractive imaging (CXDI) data from finite crystals in the frame of the dynamical theory of x-ray diffraction. The developed approach is based on a numerical solution of modified Takagi-Taupin equations and can be applied for modeling of a broad range of x-ray diffraction experiments with finite three-dimensional crystals of arbitrary shape also in the presence of strain. We performed simulations for nanocrystals of a cubic and hemispherical shape of different sizes and provided a detailed analysis of artifacts in the Bragg CXDI reconstructions introduced by the dynamical diffraction. Based on our theoretical analysis we developed an analytical procedure to treat effects of refraction and absorption in the reconstruction. Our results elucidate limitations for the kinematical approach in the Bragg CXDI and suggest a natural criterion to distinguish between kinematical and dynamical cases in coherent x-ray diffraction on a finite crystal.

Environmental impact on construction limestone at humid regions with an emphasis on salt weathering, Al-hambra islamic archaeological site, Granada City, Spain: case study

NASA Astrophysics Data System (ADS)

Kamh, G. M. E.

2007-08-01

Al-hambra is an immense and valuable archaeological site in Spain built on Sabika hill with red brick and natural sandy limestone. It exhibits weathering features indicating salt weathering process. The main aim of this study is to examine weathering processes and intensity acting on Al-hambra. Rock petrography and mineralogical composition have been examined using thin sections, scanning electron microscope, X-ray diffraction and X-ray fluorescence; limits of rock’s physical parameters using ultrasonic waves and mercury porosimeter; rock salt content through hydrochemical analysis. Salts attacking this structure are mainly from wet deposition of air pollutants on the long term chemical alteration of rock’s carbonate content to its equivalent salts. The salts’ concentration limit within the examined rock samples is considerably low but it is effective on the long run through hydration of sulphate salts and/or crystallization of chloride salts. Rock texture type and its silica as well as clay content reduces its resistance to internal stresses by salts as well as wetting and drying cycles at such humid area. The recession in limits of physical parameters examined for deep seated and weathered limestone samples quantitatively reflects weathering intensity on Al-hambra.

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

NASA Technical Reports Server (NTRS)

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

2010-01-01

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

Alteration of immature sedimentary rocks on Earth and Mars. Recording Aqueous and Surface-atmosphere Processes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cannon, Kenneth M.; Mustard, John F.; Salvatore, Mark R.

The rock alteration and rind formation in analog environments like Antarctica may provide clues to rock alteration and therefore paleoclimates on Mars. Clastic sedimentary rocks derived from basaltic sources have been studied in situ by martian rovers and are likely abundant on the surface of Mars. Moreover, how such rock types undergo alteration when exposed to different environmental conditions is poorly understood compared with alteration of intact basaltic flows. Here we characterize alteration in the chemically immature Carapace Sandstone from Antarctica, a terrestrial analog for martian sedimentary rocks. We employ a variety of measurements similar to those used on previousmore » and current Mars missions. Laboratory techniques included bulk chemistry, powder X-ray diffraction (XRD), hyperspectral imaging and X-ray absorption spectroscopy. Through these methods we find that primary basaltic material in the Carapace Sandstone is pervasively altered to hydrated clay minerals and palagonite as a result of water–rock interaction. A thick orange rind is forming in current Antarctic conditions, superimposing this previous aqueous alteration signature. The rind exhibits a higher reflectance at visible-near infrared wavelengths than the rock interior, with an enhanced ferric absorption edge likely due to an increase in Fe 3+ of existing phases or the formation of minor iron (oxy)hydroxides. This alteration sequence in the Carapace Sandstone results from decreased water–rock interaction over time, and weathering in a cold, dry environment, mimicking a similar transition early in martian history. This transition may be recorded in sedimentary rocks on Mars through a similar superimposition mechanism, capturing past climate changes at the hand sample scale. These results also suggest that basalt-derived sediments could have sourced significant volumes of hydrated minerals on early Mars due to their greater permeability compared with intact igneous rocks.« less

Potentially Reactive Forms of Silica in Volcanic Rocks Using Different Analytical Approaches

NASA Astrophysics Data System (ADS)

Esteves, Hugo; Fernandes, Isabel; Janeiro, Ana; Santos Silva, António; Pereira, Manuel; Medeiros, Sara; Nunes, João Carlos

2017-12-01

Several concrete structures show signs of deterioration resulting from internal chemical reactions, such as the alkali-silica reaction (ASR). It is well known that these swelling reactions occur in the presence of moisture, between some silica mineral phases present in the aggregates and the alkalis of the concrete, leading to the degradation of concrete structures and consequently compromising their safety. In most of the cases, rehabilitation, demolition or even rebuilding of such structures is needed and the effective costs can be very high. Volcanic rocks are commonly used as aggregates in concrete, and they are sometimes the only option due to the unavailability of other rock types. These rocks may contain different forms of silica that are deleterious to concrete, such as opal, chalcedony, cristobalite, tridymite and micro- to cryptocrystalline quartz, as well as Si-rich volcanic glass. Volcanic rocks are typically very finegrained and their constituting minerals are usually not distinguished under optical microscopy, thus leading to using complementary methods. The objective of this research is to find the more adequate analytical methods to identify silica phases that might be present in volcanic aggregates and cause ASR. The complementary methods used include X-Ray Diffraction (XRD), mineral acid digestion and Scanning Electron Microscopy with Energy Dispersive X-Ray Spectrometry (SEM/EDS), as well as Electron Probe Micro-Analysis (EPMA).

Philip A. Parilla | NREL

Science.gov Websites

atomic layer deposition for applications. He also manages the majority of X-ray characterization equipment at NREL, specifically X-ray diffraction and X-ray fluorescence instrumentation. Additionally, he for EERE's Hydrogen Storage program. He is also an expert in X-ray diffraction and X-ray fluorescence

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

PubMed

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

2018-05-01

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

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tang, M. X.; Zhang, Y. Y.; E, J. C.

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

Structural evolution of dilute magnetic (Sn,Mn)Se films grown by molecular beam epitaxy

NASA Astrophysics Data System (ADS)

Kanzyuba, Vasily; Dong, Sining; Liu, Xinyu; Li, Xiang; Rouvimov, Sergei; Okuno, Hanako; Mariette, Henri; Zhang, Xueqiang; Ptasinska, Sylwia; Tracy, Brian D.; Smith, David J.; Dobrowolska, Margaret; Furdyna, Jacek K.

2017-02-01

We describe the structural evolution of dilute magnetic (Sn,Mn)Se films grown by molecular beam epitaxy on GaAs (111) substrates, as revealed by transmission electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. When the Mn concentration is increased, the lattice of the ternary (Sn,Mn)Se films evolves quasi-coherently from a SnSe2 two-dimensional (2D) crystal structure into a more complex quasi-2D lattice rearrangement, ultimately transforming into the magnetically concentrated antiferromagnetic MnSe 3D rock-salt structure as Mn approaches 50 at. % of this material. These structural transformations are expected to underlie the evolution of magnetic properties of this ternary system reported earlier in the literature.

Field Geology/Processes

NASA Technical Reports Server (NTRS)

Allen, Carlton; Jakes, Petr; Jaumann, Ralf; Marshall, John; Moses, Stewart; Ryder, Graham; Saunders, Stephen; Singer, Robert

1996-01-01

The field geology/process group examined the basic operations of a terrestrial field geologist and the manner in which these operations could be transferred to a planetary lander. Four basic requirements for robotic field geology were determined: geologic content; surface vision; mobility; and manipulation. Geologic content requires a combination of orbital and descent imaging. Surface vision requirements include range, resolution, stereo, and multispectral imaging. The minimum mobility for useful field geology depends on the scale of orbital imagery. Manipulation requirements include exposing unweathered surfaces, screening samples, and bringing samples in contact with analytical instruments. To support these requirements, several advanced capabilities for future development are recommended. Capabilities include near-infrared reflectance spectroscopy, hyper-spectral imaging, multispectral microscopy, artificial intelligence in support of imaging, x ray diffraction, x ray fluorescence, and rock chipping.

Characterization of Dislocations in Semiconductor Heterostructures Using X-ray Rocking Curve Pendellösung

NASA Astrophysics Data System (ADS)

Althowibi, Fahad A.; Ayers, John E.

2018-02-01

In this work we investigated the dislocation-dependent behavior of Pendellösung fringes from two types of semiconductor heterostructures: a uniform-composition InGaAs epitaxial layer grown on a GaAs (001) substrate with an intermediate step-graded InGaAs buffer, and an InGaAs/InAlAs high electron mobility transistor grown on an InP (001) substrate. Dynamical x-ray diffraction simulations were carried out in the 004, 115,135, and 117 geometry, assuming Cu kα1 incident radiation, for both structures. The dislocation density strongly affects the intensities and widths of Pendellösung fringes, and we have established quantitative relationships which will allow characterization of the dislocation density.

Coherent X-ray diffraction imaging of nanoengineered polymeric capsules

NASA Astrophysics Data System (ADS)

Erokhina, S.; Pastorino, L.; Di Lisa, D.; Kiiamov, A. G.; Faizullina, A. R.; Tayurskii, D. A.; Iannotta, S.; Erokhin, V.

2017-10-01

For the first time, nanoengineered polymeric capsules and their architecture have been studied with coherent X-ray diffraction imaging technique. The use of coherent X-ray diffraction imaging technique allowed us to analyze the samples immersed in a liquid. We report about the significant difference between polymeric capsule architectures under dry and liquid conditions.

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

Murray, Thomas D.; Johns Hopkins University School of Medicine, Baltimore, MD 21205; Lyubimov, Artem Y.

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 themore » 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.« less

Enhancement of crystal homogeneity of protein crystals under application of an external alternating current electric field

DOE Office of Scientific and Technical Information (OSTI.GOV)

Koizumi, H.; Uda, S.; Fujiwara, K.

X-ray diffraction rocking-curve measurements were performed on tetragonal hen egg white (HEW) lysozyme crystals grown with and without the application of an external alternating current (AC) electric field. The crystal quality was assessed by the full width at half maximum (FWHM) value for each rocking curve. For two-dimensional maps of the FWHMs measured on the 440 and the 12 12 0 reflection, the crystal homogeneity was improved under application of an external electric field at 1 MHz, compared with that without. In particular, the significant improvement of the crystal homogeneity was observed for the 12 12 0 reflection.

Growth and luminescent properties of Yb:YAG and Ca co-doped Yb:YAG ultrafast scintillation crystals

NASA Astrophysics Data System (ADS)

Zhu, Maodong; Qi, Hongji; Pan, Mingyan; Hou, Qing; Jiang, Benxue; Jin, Yaxue; Han, Hetong; Song, Zhaohui; Zhang, Hui

2018-05-01

In this work, Yb-doped Y3Al5O12 [yttrium aluminum garnet (YAG)] crystals and Ca co-doped Yb:YAG crystals were grown by the Czochralski (CZ) method. The chemical formulas of the two crystals are (Yb0.1Y0.9)3Al5O12 and (Ca0.001Yb0.1Y0.899)3Al5O12, respectively. The structural, optical and luminescent properties of the Yb:YAG and Ca, Yb:YAG crystals were investigated by X-ray rocking curve, X-ray diffraction, Raman spectra, UV-Visble-NIR absorption spectra and X-ray fluorescence. X-ray fluorescence spectrum with two emission peaks at 330 nm and 490 nm were observed in the two kinds of crystals, which would increase slightly after the annealing. Comparing to the Yb:YAG crystal, Ca co-doped Yb:YAG crystal behaved the better luminescent intensity without changing the crystal structure and vibrational modes. This indicates that by doping Ca2+ in Yb:YAG crystal may be an appropriate way to enhance the luminescent property of the scintillation crystal.

X-Ray Structure determination of the Glycine Cleavage System Protein H of Mycobacterium tuberculosis Using An Inverse Compton Synchrotron X-Ray Source

PubMed Central

Abendroth, Jan; McCormick, Michael S.; Edwards, Thomas E.; Staker, Bart; Loewen, Roderick; Gifford, Martin; Rifkin, Jeff; Mayer, Chad; Guo, Wenjin; Zhang, Yang; Myler, Peter; Kelley, Angela; Analau, Erwin; Hewitt, Stephen Nakazawa; Napuli, Alberto J.; Kuhn, Peter; Ruth, Ronald D.; Stewart, Lance J.

2010-01-01

Structural genomics discovery projects require ready access to both X-ray and NMR instrumentation which support the collection of experimental data needed to solve large numbers of novel protein structures. The most productive X-ray crystal structure determination laboratories make extensive frequent use of tunable synchrotron X-ray light to solve novel structures by anomalous diffraction methods. This requires that frozen cryo-protected crystals be shipped to large government-run synchrotron facilities for data collection. In an effort to eliminate the need to ship crystals for data collection, we have developed the first laboratory-scale synchrotron light source capable of performing many of the state-of-the-art synchrotron applications in X-ray science. This Compact Light Source is a first-in-class device that uses inverse Compton scattering to generate X-rays of sufficient flux, tunable wavelength and beam size to allow high-resolution X-ray diffraction data collection from protein crystals. We report on benchmarking tests of X-ray diffraction data collection with hen egg white lysozyme, and the successful high-resolution X-ray structure determination of the Glycine cleavage system protein H from Mycobacterium tuberculosis using diffraction data collected with the Compact Light Source X-ray beam. PMID:20364333

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

DOE PAGES

Huang, Xiaojing; Miao, Huijie; Nelson, Johanna; ...

2011-05-01

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

Observation of electromigration in a Cu thin line by in situ coherent x-ray diffraction microscopy

NASA Astrophysics Data System (ADS)

Takahashi, Yukio; Nishino, Yoshinori; Furukawa, Hayato; Kubo, Hideto; Yamauchi, Kazuto; Ishikawa, Tetsuya; Matsubara, Eiichiro

2009-06-01

Electromigration (EM) in a 1-μm-thick Cu thin line was investigated by in situ coherent x-ray diffraction microscopy (CXDM). Characteristic x-ray speckle patterns due to both EM-induced voids and thermal deformation in the thin line were observed in the coherent x-ray diffraction patterns. Both parts of the voids and the deformation were successfully visualized in the images reconstructed from the diffraction patterns. This result not only represents the first demonstration of the visualization of structural changes in metallic materials by in situ CXDM but is also an important step toward studying the structural dynamics of nanomaterials using x-ray free-electron lasers in the near future.

Laboratory Detection and Analysis of Organic Compounds in Rocks Using HPLC and XRD Methods

NASA Technical Reports Server (NTRS)

Dragoi, D.; Kanik, I.; Bar-Cohen, Y.; Sherrit, S.; Tsapin, A.; Kulleck, J.

2004-01-01

In this work we describe an analytical method for determining the presence of organic compounds in rocks, limestone, and other composite materials. Our preliminary laboratory experiments on different rocks/limestone show that the organic component in mineralogical matrices is a minor phase on order of hundreds of ppm and can be better detected using high precision liquid chromatography (HPLC). The matrix, which is the major phase, plays an important role in embedding and protecting the organic molecules from the harsh Martian environment. Some rocks bear significant amounts of amino acids therefore, it is possible to identify these phases using powder x-ray diffraction (XRD) by crystallizing the organic. The method of detection/analysis of organics, in particular amino acids, that have been associated with life will be shown in the next section.

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

PubMed

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

2014-04-01

X-ray diffraction (XRD) and X-ray absorption spectroscopy (XAS) are two main x-ray techniques in synchrotron radiation facilities. In this Note, we present an experimental setup capable of performing simultaneous XRD and XAS measurements by the application of a pixel-array area detector. For XRD, the momentum transfer in specular diffraction was measured by scanning the X-ray energy with fixed incoming and outgoing x-ray angles. By selecting a small fixed region of the detector to collect the XRD signal, the rest of the area was available for collecting the x-ray fluorescence for XAS measurements. The simultaneous measurement of XRD and X-ray absorption near edge structure for Pr0.67Sr0.33MnO3 film was demonstrated as a proof of principle for future time-resolved pump-probe measurements. A static sample makes it easy to maintain an accurate overlap of the X-ray spot and laser pump beam.

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

NASA Technical Reports Server (NTRS)

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

2010-01-01

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

Diffraction based method to reconstruct the spectrum of the Thomson scattering x-ray source

NASA Astrophysics Data System (ADS)

Chi, Zhijun; Yan, Lixin; Zhang, Zhen; Zhou, Zheng; Zheng, Lianmin; Wang, Dong; Tian, Qili; Wang, Wei; Nie, Zan; Zhang, Jie; Du, Yingchao; Hua, Jianfei; Shi, Jiaru; Pai, Chihao; Lu, Wei; Huang, Wenhui; Chen, Huaibi; Tang, Chuanxiang

2017-04-01

As Thomson scattering x-ray sources based on the collision of intense laser and relativistic electrons have drawn much attention in various scientific fields, there is an increasing demand for the effective methods to reconstruct the spectrum information of the ultra-short and high-intensity x-ray pulses. In this paper, a precise spectrum measurement method for the Thomson scattering x-ray sources was proposed with the diffraction of a Highly Oriented Pyrolytic Graphite (HOPG) crystal and was demonstrated at the Tsinghua Thomson scattering X-ray source. The x-ray pulse is diffracted by a 15 mm (L) ×15 mm (H)× 1 mm (D) HOPG crystal with 1° mosaic spread. By analyzing the diffraction pattern, both x-ray peak energies and energy spectral bandwidths at different polar angles can be reconstructed, which agree well with the theoretical value and simulation. The higher integral reflectivity of the HOPG crystal makes this method possible for single-shot measurement.

Diffraction based method to reconstruct the spectrum of the Thomson scattering x-ray source.

PubMed

Chi, Zhijun; Yan, Lixin; Zhang, Zhen; Zhou, Zheng; Zheng, Lianmin; Wang, Dong; Tian, Qili; Wang, Wei; Nie, Zan; Zhang, Jie; Du, Yingchao; Hua, Jianfei; Shi, Jiaru; Pai, Chihao; Lu, Wei; Huang, Wenhui; Chen, Huaibi; Tang, Chuanxiang

2017-04-01

As Thomson scattering x-ray sources based on the collision of intense laser and relativistic electrons have drawn much attention in various scientific fields, there is an increasing demand for the effective methods to reconstruct the spectrum information of the ultra-short and high-intensity x-ray pulses. In this paper, a precise spectrum measurement method for the Thomson scattering x-ray sources was proposed with the diffraction of a Highly Oriented Pyrolytic Graphite (HOPG) crystal and was demonstrated at the Tsinghua Thomson scattering X-ray source. The x-ray pulse is diffracted by a 15 mm (L) ×15 mm (H)× 1 mm (D) HOPG crystal with 1° mosaic spread. By analyzing the diffraction pattern, both x-ray peak energies and energy spectral bandwidths at different polar angles can be reconstructed, which agree well with the theoretical value and simulation. The higher integral reflectivity of the HOPG crystal makes this method possible for single-shot measurement.

Gas gun shock experiments with single-pulse x-ray phase contrast imaging and diffraction at the Advanced Photon Source

NASA Astrophysics Data System (ADS)

Luo, S. N.; Jensen, B. J.; Hooks, D. E.; Fezzaa, K.; Ramos, K. J.; Yeager, J. D.; Kwiatkowski, K.; Shimada, T.

2012-07-01

The highly transient nature of shock loading and pronounced microstructure effects on dynamic materials response call for in situ, temporally and spatially resolved, x-ray-based diagnostics. Third-generation synchrotron x-ray sources are advantageous for x-ray phase contrast imaging (PCI) and diffraction under dynamic loading, due to their high photon fluxes, high coherency, and high pulse repetition rates. The feasibility of bulk-scale gas gun shock experiments with dynamic x-ray PCI and diffraction measurements was investigated at the beamline 32ID-B of the Advanced Photon Source. The x-ray beam characteristics, experimental setup, x-ray diagnostics, and static and dynamic test results are described. We demonstrate ultrafast, multiframe, single-pulse PCI measurements with unprecedented temporal (<100 ps) and spatial (˜2 μm) resolutions for bulk-scale shock experiments, as well as single-pulse dynamic Laue diffraction. The results not only substantiate the potential of synchrotron-based experiments for addressing a variety of shock physics problems, but also allow us to identify the technical challenges related to image detection, x-ray source, and dynamic loading.

Mineralogical compositions of fault rocks from surface ruptures of Wenchuan earthquake and implication of mineral transformation during the seismic cycle along Yingxiu-Beichuan fault, Sichuan Province, China

NASA Astrophysics Data System (ADS)

Dang, Jiaxiang; Zhou, Yongsheng; He, Changrong; Ma, Shengli

2018-06-01

There are two co-seismic bedrock surface ruptures from the Mw 7.9 Wenchuan earthquake in the northern and central parts of the Beichuan-Yingxiu fault, Sichuan Province, southwest China. In this study, we report on the macrostructure of the fault rocks and results from X-ray powder diffraction analysis of minerals from rocks in the fault zone. The most recent fault gouge (the gouge produced by the most recent co-seismic fault movement) in all the studied outcrops is dark or grayish-black, totally unconsolidated and ultrafine-grained. Older fault gouges in the same outcrops are grayish or yellowish and weakly consolidated. X-ray powder diffraction analysis results show that mineral assemblages in both the old fault gouge and the new fault gouge are more complicated than the mineral assemblages in the bedrock as the fault gouge is rich in clay minerals. The fault gouge inherited its major rock-forming minerals from the parent rocks, but the clay minerals in the fault gouge were generated in the fault zone and are therefore authigenic and synkinematic. In profiles across the fault, clay mineral abundances increase as one traverses from the bedrock to the breccia to the old gouge and from the old gouge to the new gouge. Quartz and illite are found in all collected gouge samples. The dominant clay minerals in the new fault gouge are illite and smectite along the northern part of the surface rupture and illite/smectite mixed-layer clay in the middle part of the rupture. Illite/smectite mixed-layer clay found in the middle part of the rupture indicates that fault slip was accompanied by K-rich fluid circulation. The existence of siderite, anhydrite, and barite in the northern part of the rupture suggests that fault slip at this locality was accompanied by acidic fluids containing ions of Fe, Ca, and Ba.

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

PubMed

Girardin, E; Millet, P; Lodini, A

2000-02-01

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

X-ray Diffraction Gratings for Astrophysics

NASA Astrophysics Data System (ADS)

Paerels, Frits

2010-12-01

Over the past year, we have celebrated the tenth anniversary of the Chandra and XMM-Newton X-ray observatories. Both carry powerful, novel diffraction grating spectrometers, which have opened true X-ray spectroscopy for astrophysics. I will describe the design and operation of these instruments, as the background to some of the beautiful results they have produced. But these designs do not exhaust the versatility and essential simplicity of diffraction grating spectrometers, and I will discuss applications for the International X-ray Observatory IXO.

Recognizing Sulfate and Phosphate Complexes Adsorbed onto Nanophase Weathering Products on Mars

NASA Technical Reports Server (NTRS)

Rampe, E. B.; Morris, R. V.; Archer, P. D., Jr.

2015-01-01

Nanophase weathering products (i.e., secondary phases that lack long-range atomic order) have been recognized on the martian surface via orbital observations and in-situ measurements from landed missions. Allophane, a poorly crystalline, hydrated aluminosilicate, has been identified at the regional scale in models of thermal-infrared (TIR) data from the Thermal Emission Spectrometer (TES) and at the local scale from visible/near-IR (VNIR) data from the Compact Reconnaissance Impact Spectrometer for Mars (CRISM) instrument and phase calculations of Alpha Particle X-ray Spectrometer (APXS) data of rocks encountered by the Mars Exploration Rovers (MER) Spirit and Opportunity. Nanophase iron oxides (npOx) have been recognized in rocks and soils measured by the Mössbauer Spectrometer on Spirit and Opportunity. Furthermore, analyses of X-ray diffraction data measured by the CheMin instrument onboard the Mars Science Laboratory rover Curiosity indicate rock and soil samples are comprised of approx. 20-50 wt.% X-ray amorphous materials. Chemical measurements by landed missions indicate the presence of sulfur and phosphorus in martian rocks in soils, and APXS data from Gusev crater demonstrate abundances of up to approx. 5 wt.% P2O5 and approx. 30 wt.% SO3. However, the speciation of phosphorus and sulfur is not always evident. On Earth, phosphate and sulfate anions can be chemisorbed onto the surfaces of nanophase weathering products. This process may also occur on Mars, and calculations of the composition of the amorphous component at Gale crater using CheMin mineral models and APXS data show that amorphous material is enriched in volatiles, including S. Here, we examine the ability to detect chemisorbed sulfate and phosphate complexes by analyzing sulfate- and phosphate-adsorbed nanophase weathering products using instruments similar to those on landed and orbital missions.

Amorphous boron gasket in diamond anvil cell research

NASA Astrophysics Data System (ADS)

Lin, Jung-Fu; Shu, Jinfu; Mao, Ho-kwang; Hemley, Russell J.; Shen, Guoyin

2003-11-01

Recent advances in high-pressure diamond anvil cell experiments include high-energy synchrotron x-ray techniques as well as new cell designs and gasketing procedures. The success of high-pressure experiments usually depends on a well-prepared sample, in which the gasket plays an important role. Various gasket materials such as diamond, beryllium, rhenium, and stainless steel have been used. Here we introduce amorphous boron as another gasket material in high-pressure diamond anvil cell experiments. We have applied the boron gasket for laser-heating x-ray diffraction, radial x-ray diffraction, nuclear resonant inelastic x-ray scattering, and inelastic x-ray scattering. The high shear strength of the amorphous boron maximizes the thickness of the sample chamber and increases the pressure homogeneity, improving the quality of high-pressure data. Use of amorphous boron avoids unwanted x-ray diffraction peaks and reduces the absorption of incident and x rays exiting the gasket material. The high quality of the diffraction patterns makes it possible to refine the cell parameters with powder x-ray diffraction data under high pressure and high temperature. The reactivity of boron prevents its use at high temperatures, however. When heated, boron may also react with the specimen to produce unwanted phases. The relatively porous boron starting material at ambient conditions also poses some challenges for sample preparation.

X-Ray Sum Frequency Diffraction for Direct Imaging of Ultrafast Electron Dynamics

NASA Astrophysics Data System (ADS)

Rouxel, Jérémy R.; Kowalewski, Markus; Bennett, Kochise; Mukamel, Shaul

2018-06-01

X-ray diffraction from molecules in the ground state produces an image of their charge density, and time-resolved x-ray diffraction can thus monitor the motion of the nuclei. However, the density change of excited valence electrons upon optical excitation can barely be monitored with regular diffraction techniques due to the overwhelming background contribution of the core electrons. We present a nonlinear x-ray technique made possible by novel free electron laser sources, which provides a spatial electron density image of valence electron excitations. The technique, sum frequency generation carried out with a visible pump and a broadband x-ray diffraction pulse, yields snapshots of the transition charge densities, which represent the electron density variations upon optical excitation. The technique is illustrated by ab initio simulations of transition charge density imaging for the optically induced electronic dynamics in a donor or acceptor substituted stilbene.

Amorphous silica maturation in chemically weathered clastic sediments

NASA Astrophysics Data System (ADS)

Liesegang, Moritz; Milke, Ralf; Berthold, Christoph

2018-03-01

A detailed understanding of silica postdepositional transformation mechanisms is fundamental for its use as a palaeobiologic and palaeoenvironmental archive. Amorphous silica (opal-A) is an important biomineral, an alteration product of silicate rocks on the surface of Earth and Mars, and a precursor material for stable silica phases. During diagenesis, amorphous silica gradually and gradationally transforms to opal-CT, opal-C, and eventually quartz. Here we demonstrate the early-stage maturation of several million year old opal-A from deeply weathered Early Cretaceous and Ordovician sedimentary rocks of the Great Artesian Basin (central Australia). X-ray diffraction, scanning electron microscopy, and electron probe microanalyses show that the mineralogical maturation of the nanosphere material is decoupled from its chemical properties and begins significantly earlier than micromorphology suggests. Non-destructive and locally highly resolved X-ray microdiffraction (μ-XRD2) reveals an almost linear positive correlation between the main peak position (3.97 to 4.06 Å) and a new asymmetry parameter, AP. Heating experiments and calculated diffractograms indicate that nucleation and growth of tridymite-rich nanodomains induce systematic peak shifts and symmetry variations in diffraction patterns of morphologically juvenile opal-A. Our results show that the asymmetry parameter traces the early-stage maturation of amorphous silica, and that the mineralogical opal-A/CT stage extends to smaller d-spacings and larger FWHM values than previously suggested.

Quantitative determination of occupation sites of trace Co substituted for multiple Fe sites in M-type hexagonal ferrite using statistical beam-rocking TEM-EDXS analysis.

PubMed

Ohtsuka, Masahiro; Muto, Shunsuke; Tatsumi, Kazuyoshi; Kobayashi, Yoshinori; Kawata, Tsunehiro

2016-04-01

The occupation sites and the occupancies of trace dopants in La/Co co-doped Sr-M-type ferrite, SrFe12O19, were quantitatively and precisely determined by beam-rocking energy-dispersive X-ray spectroscopy (EDXS) on the basis of electron-channeling effects. Because the Co atoms, in particular, should be partially substituted for the five crystallographically inequivalent sites, which could be key parameters in improving the magneto-crystalline anisotropy, it is difficult yet intriguing to discover their occupation sites and occupancies without using the methods of large-scale facilities, such as neutron diffraction and synchrotron radiation. In the present study, we tackled this problem by applying an extended statistical atom location by channeling enhanced microanalysis method, using conventional transmission electron microscopy, EDXS and dynamical electron elastic/inelastic scattering theories. The results show that the key occupation sites of Co were the 2a, 4f1 and 12k sites. The quantified occupancies of Co were consistent with those of the previous study, which involved a combination of neutron diffraction and extended X-ray absorption fine structure analysis, as well as energetics considerations based on by first-principles calculations. © The Author 2015. Published by Oxford University Press on behalf of The Japanese Society of Microscopy. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

The Mapping X-ray Fluorescence Spectrometer (MapX)

NASA Astrophysics Data System (ADS)

Sarrazin, P.; Blake, D. F.; Marchis, F.; Bristow, T.; Thompson, K.

2017-12-01

Many planetary surface processes leave traces of their actions as features in the size range 10s to 100s of microns. The Mapping X-ray Fluorescence Spectrometer (MapX) will provide elemental imaging at 100 micron spatial resolution, yielding elemental chemistry at a scale where many relict physical, chemical, or biological features can be imaged and interpreted in ancient rocks on planetary bodies and planetesimals. MapX is an arm-based instrument positioned on a rock or regolith with touch sensors. During an analysis, an X-ray source (tube or radioisotope) bombards the sample with X-rays or alpha-particles / gamma-rays, resulting in sample X-ray Fluorescence (XRF). X-rays emitted in the direction of an X-ray sensitive CCD imager pass through a 1:1 focusing lens (X-ray micro-pore Optic (MPO)) that projects a spatially resolved image of the X-rays onto the CCD. The CCD is operated in single photon counting mode so that the energies and positions of individual X-ray photons are recorded. In a single analysis, several thousand frames are both stored and processed in real-time. Higher level data products include single-element maps with a lateral spatial resolution of 100 microns and quantitative XRF spectra from ground- or instrument- selected Regions of Interest (ROI). XRF spectra from ROI are compared with known rock and mineral compositions to extrapolate the data to rock types and putative mineralogies. When applied to airless bodies and implemented with an appropriate radioisotope source for alpha-particle excitation, MapX will be able to analyze biogenic elements C, N, O, P, S, in addition to the cations of the rock-forming elements >Na, accessible with either X-ray or gamma-ray excitation. The MapX concept has been demonstrated with a series of lab-based prototypes and is currently under refinement and TRL maturation.

Heavy Metal Contamination and Salt Efflorescence Associated With Decorative Landscaping Rocks, Las Vegas, Nevada: The Need for Regulations

NASA Astrophysics Data System (ADS)

Mrozek, S. A.; Buck, B. J.; Brock, A. L.

2004-12-01

Las Vegas, Nevada is one of the fastest growing cities in the United States. Faced with water restrictions, decorative rock xeroscaping has become a very popular form of landscaping. Currently, there are no regulations controlling the geochemistry of the decorative rocks that can be used for these purposes. In this study, we examined three sites containing two different decorative rock products. The landscaping rocks, underlying soil, and surface salt crusts were analyzed to determine their mineralogy and chemistry. Methods of analysis include scanning electron microscopy (SEM), energy dispersive X-ray spectrometry (EDS), X-ray diffraction (XRD), inductively coupled plasma atomic emission spectroscopy (ICP), thin section analysis, and laser particle size analysis (LPSA). Preliminary results indicate the presence of halite (NaCl), bloedite (Na2Mg(SO4)2 4H2O), a hydrated magnesium sulfate, and possibly copper sulfate and copper chloride mineral phases in the surface salt crusts. Both copper minerals are regarded as hazardous substances by the Occupational Safety and Health Administration (OSHA) and the Environmental Protection Agency (EPA); these agencies have established minimum exposure limits for human contact with these substances. Copper sulfate and copper chloride are not naturally occurring minerals in the soils of the Las Vegas Valley, and analyses indicate that their formation may be attributed to the mineralogy of the decorative landscaping rocks. Further testing is needed to characterize this potential health hazard; however the preliminary results of this study demonstrate the need for regulations controlling the geochemistry of decorative rocks used for urban landscaping.

Effects of Kapton Sample Cell Windows on the Detection Limit of Smectite: Implications for CheMin on the Mars Science Laboratory Mission

NASA Technical Reports Server (NTRS)

Achilles, C. N.; Ming, Douglas W.; Morris, R. V.; Blake, D. F.

2012-01-01

The CheMin instrument on the Mars Science Laboratory (MSL) rover Curiosity is an X-ray diffraction (XRD) and X-ray fluorescence (XRF) instrument capable of providing the mineralogical and chemical compositions of rocks and soils on the surface of Mars. CheMin uses a microfocus X-ray tube with a Co target, transmission geometry, and an energy-discriminating X-ray sensitive CCD to produce simultaneous 2-D XRD patterns and energy-dispersive X-ray histograms from powdered samples. CheMin has two different window materials used for sample cells -- Mylar and Kapton. Instrument details are provided elsewhere. Fe/Mg-smectite (e.g., nontronite) has been identified in Gale Crater, the MSL future landing site, by CRISM spectra. While large quantities of phyllosilicate minerals will be easily detected by CheMin, it is important to establish detection limits of such phases to understand capabilities and limitations of the instrument. A previous study indicated that the (001) peak of smectite at 15 Ang was detectable in a mixture of 1 wt.% smectite with olivine when Mylar is the window material for the sample cell. Complications arise when Kapton is the window material because Kapton itself also has a diffraction peak near 15 Ang (6.8 deg 2 Theta). This study presents results of mineral mixtures of smectite and olivine to determine smectite detection limits for Kapton sample cells. Because the intensity and position of the smectite (001) peak depends on the hydration state, we also analyzed mixtures with "hydrated" and "dehydrated"h smectite to examine the effects of hydration state on detection limits.

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

PubMed

Nam, Daewoong; Park, Jaehyun; Gallagher-Jones, Marcus; Shimada, Hiroki; Kim, Sangsoo; Kim, Sunam; Kohmura, Yoshiki; Ishikawa, Tetsuya; Song, Changyong

2013-11-01

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

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

NASA Astrophysics Data System (ADS)

Nam, Daewoong; Park, Jaehyun; Gallagher-Jones, Marcus; Shimada, Hiroki; Kim, Sangsoo; Kim, Sunam; Kohmura, Yoshiki; Ishikawa, Tetsuya; Song, Changyong

2013-11-01

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

Thin Film Research. Volume 1

DTIC Science & Technology

1985-05-30

Order (FECO) ......... 23 3. X -Ray Diffraction ............................... 26 4. Transmission Electron Microscopy (TEM) ............... 26 5...remained amorphous after bombardment, as evidenced by X - ray diffraction, and showed no other changes. 0 (2) For Sb203, the crystallite size was reduced...main effect on MgF2 was the reduction in crystallite size. The films were too thir. for meaningful x - ray diffraction analysis. Durability and

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

ERIC Educational Resources Information Center

Crouse, David T.

2007-01-01

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

Hard X-ray polarizer to enable simultaneous three-dimensional nanoscale imaging of magnetic structure and lattice strain

DOE PAGES

Logan, Jonathan; Harder, Ross; Li, Luxi; ...

2016-01-01

Recent progress in the development of dichroic Bragg coherent diffractive imaging, a new technique for simultaneous three-dimensional imaging of strain and magnetization at the nanoscale, is reported. This progress includes the installation of a diamond X-ray phase retarder at beamline 34-ID-C of the Advanced Photon Source. Here, the performance of the phase retarder for tuning X-ray polarization is demonstrated with temperature-dependent X-ray magnetic circular dichroism measurements on a gadolinium foil in transmission and on a Gd 5Si 2Ge 2crystal in diffraction geometry with a partially coherent, focused X-ray beam. Feasibility tests for dichroic Bragg coherent diffractive imaging are presented. Thesemore » tests include (1) using conventional Bragg coherent diffractive imaging to determine whether the phase retarder introduces aberrations using a nonmagnetic gold nanocrystal as a control sample, and (2) collecting coherent diffraction patterns of a magnetic Gd 5Si 2Ge 2nanocrystal with left- and right-circularly polarized X-rays. Future applications of dichroic Bragg coherent diffractive imaging for the correlation of strain and lattice defects with magnetic ordering and inhomogeneities are considered.« less

Three Dimensional Variable-Wavelength X-Ray Bragg Coherent Diffraction Imaging

DOE PAGES

Cha, W.; Ulvestad, A.; Allain, M.; ...

2016-11-23

Here, we present and demonstrate a formalism by which three-dimensional (3D) Bragg x-ray coherent diffraction imaging (BCDI) can be implemented without moving the sample by scanning the energy of the incident x-ray beam. This capability is made possible by introducing a 3D Fourier transform that accounts for x-ray wavelength variability. We also demonstrate the approach by inverting coherent Bragg diffraction patterns from a gold nanocrystal measured with an x-ray energy scan. Furthermore, variable-wavelength BCDI will expand the breadth of feasible in situ 3D strain imaging experiments towards more diverse materials environments, especially where sample manipulation is difficult.

Synchrotron X-Ray Diffraction Analysis of Meteorites in Thin Section: Preliminary Results

NASA Technical Reports Server (NTRS)

Treiman, A. H.; Lanzirotti, A.; Xirouchakis, D.

2004-01-01

X-ray diffraction is the pre-eminent technique for mineral identification and structure determination, but is difficult to apply to grains in thin section, the standard meteorite preparation. Bright focused X-ray beams from synchrotrons have been used extensively in mineralogy and have been applied to extraterrestrial particles. The intensity and small spot size achievable in synchrotron X-ray beams makes them useful for study of materials in thin sections. Here, we describe Synchrotron X-ray Diffraction (SXRD) in thin section as done at the National Synchrotron Light Source, and cite examples of its value for studies of meteorites in thin section.

Three Dimensional Variable-Wavelength X-Ray Bragg Coherent Diffraction Imaging

NASA Astrophysics Data System (ADS)

Cha, W.; Ulvestad, A.; Allain, M.; Chamard, V.; Harder, R.; Leake, S. J.; Maser, J.; Fuoss, P. H.; Hruszkewycz, S. O.

2016-11-01

We present and demonstrate a formalism by which three-dimensional (3D) Bragg x-ray coherent diffraction imaging (BCDI) can be implemented without moving the sample by scanning the energy of the incident x-ray beam. This capability is made possible by introducing a 3D Fourier transform that accounts for x-ray wavelength variability. We demonstrate the approach by inverting coherent Bragg diffraction patterns from a gold nanocrystal measured with an x-ray energy scan. Variable-wavelength BCDI will expand the breadth of feasible in situ 3D strain imaging experiments towards more diverse materials environments, especially where sample manipulation is difficult.

Three Dimensional Variable-Wavelength X-Ray Bragg Coherent Diffraction Imaging.

PubMed

Cha, W; Ulvestad, A; Allain, M; Chamard, V; Harder, R; Leake, S J; Maser, J; Fuoss, P H; Hruszkewycz, S O

2016-11-25

We present and demonstrate a formalism by which three-dimensional (3D) Bragg x-ray coherent diffraction imaging (BCDI) can be implemented without moving the sample by scanning the energy of the incident x-ray beam. This capability is made possible by introducing a 3D Fourier transform that accounts for x-ray wavelength variability. We demonstrate the approach by inverting coherent Bragg diffraction patterns from a gold nanocrystal measured with an x-ray energy scan. Variable-wavelength BCDI will expand the breadth of feasible in situ 3D strain imaging experiments towards more diverse materials environments, especially where sample manipulation is difficult.

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

DOEpatents

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

2007-06-26

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

The effect of exit beam phase aberrations on parallel beam coherent x-ray reconstructions

NASA Astrophysics Data System (ADS)

Hruszkewycz, S. O.; Harder, R.; Xiao, X.; Fuoss, P. H.

2010-12-01

Diffraction artifacts from imperfect x-ray windows near the sample are an important consideration in the design of coherent x-ray diffraction measurements. In this study, we used simulated and experimental diffraction patterns in two and three dimensions to explore the effect of phase imperfections in a beryllium window (such as a void or inclusion) on the convergence behavior of phasing algorithms and on the ultimate reconstruction. A predictive relationship between beam wavelength, sample size, and window position was derived to explain the dependence of reconstruction quality on beryllium defect size. Defects corresponding to this prediction cause the most damage to the sample exit wave and induce signature error oscillations during phasing that can be used as a fingerprint of experimental x-ray window artifacts. The relationship between x-ray window imperfection size and coherent x-ray diffractive imaging reconstruction quality explored in this work can play an important role in designing high-resolution in situ coherent imaging instrumentation and will help interpret the phasing behavior of coherent diffraction measured in these in situ environments.

The effect of exit beam phase aberrations on parallel beam coherent x-ray reconstructions.

PubMed

Hruszkewycz, S O; Harder, R; Xiao, X; Fuoss, P H

2010-12-01

Diffraction artifacts from imperfect x-ray windows near the sample are an important consideration in the design of coherent x-ray diffraction measurements. In this study, we used simulated and experimental diffraction patterns in two and three dimensions to explore the effect of phase imperfections in a beryllium window (such as a void or inclusion) on the convergence behavior of phasing algorithms and on the ultimate reconstruction. A predictive relationship between beam wavelength, sample size, and window position was derived to explain the dependence of reconstruction quality on beryllium defect size. Defects corresponding to this prediction cause the most damage to the sample exit wave and induce signature error oscillations during phasing that can be used as a fingerprint of experimental x-ray window artifacts. The relationship between x-ray window imperfection size and coherent x-ray diffractive imaging reconstruction quality explored in this work can play an important role in designing high-resolution in situ coherent imaging instrumentation and will help interpret the phasing behavior of coherent diffraction measured in these in situ environments.

Femtosecond X-ray Diffraction From Two-Dimensional Protein Crystals

DOE Office of Scientific and Technical Information (OSTI.GOV)

Frank, Matthias; Carlson, David B.; Hunter, Mark

2014-02-28

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

Influence of gamma ray irradiation on stoichiometry of hydrothermally synthesized bismuth telluride nanoparticles

NASA Astrophysics Data System (ADS)

Abishek, N. S.; Naik, K. Gopalakrishna

2018-05-01

Bismuth telluride (Bi2Te3) nanoparticles were synthesized by the hydrothermal method at 200 °C for 24 h. The synthesized Bi2Te3 nanoparticles were irradiated with gamma rays at doses of 50 kGy and 100 kGy. The structural characterization of the pre-irradiated and post-irradiated samples was carried out by X-ray diffraction technique and was found to have rhombohedral phase having R3 ¯m (166) space group. The X-ray diffraction peaks were found to shift towards lower diffraction angle with gamma ray irradiation. The morphologies and compositions of the grown Bi2Te3 nanoparticles were studied using Field Emission Scanning Electron Microscope and X-ray energy dispersive analysis, respectively. The possible cause for the shift in the X-ray diffraction peaks with gamma ray irradiation has been discussed in the present work.

High Power Optical Coatings by Atomic Layer Deposition and Signatures of Laser-Induced Damage

DTIC Science & Technology

2012-08-28

diffraction angle 0 into crystal lattice spacing d by the Bragg condition, mX = 2d sin 0. Here X is the x - ray wavelength... angle x - ray diffraction (GAXRD) measurements, which were made at a fixed shallow incidence angle of 0.5°. Detector scans were done to measure the...was finished with 200 hafnia cycles m the fmal half period rather than 400. Crystallinity was measured by x - ray diffraction (XRD) with

Spirit Switches on Its X-ray Vision

NASA Technical Reports Server (NTRS)

2004-01-01

This image shows the Mars Exploration Rover Spirit probing its first target rock, Adirondack. At the time this picture was snapped, the rover had begun analyzing the rock with the alpha particle X-ray spectrometer located on its robotic arm. This instrument uses alpha particles and X-rays to determine the elemental composition of martian rocks and soil. The image was taken by the rover's hazard-identification camera.

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

NASA Astrophysics Data System (ADS)

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

2016-05-01

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

Dynamic X-ray diffraction sampling for protein crystal positioning

DOE Office of Scientific and Technical Information (OSTI.GOV)

Scarborough, Nicole M.; Godaliyadda, G. M. Dilshan P.; Ye, Dong Hye

A sparse supervised learning approach for dynamic sampling (SLADS) is described for dose reduction in diffraction-based protein crystal positioning. Crystal centering is typically a prerequisite for macromolecular diffraction at synchrotron facilities, with X-ray diffraction mapping growing in popularity as a mechanism for localization. In X-ray raster scanning, diffraction is used to identify the crystal positions based on the detection of Bragg-like peaks in the scattering patterns; however, this additional X-ray exposure may result in detectable damage to the crystal prior to data collection. Dynamic sampling, in which preceding measurements inform the next most information-rich location to probe for image reconstruction,more » significantly reduced the X-ray dose experienced by protein crystals during positioning by diffraction raster scanning. The SLADS algorithm implemented herein is designed for single-pixel measurements and can select a new location to measure. In each step of SLADS, the algorithm selects the pixel, which, when measured, maximizes the expected reduction in distortion given previous measurements. Ground-truth diffraction data were obtained for a 5 µm-diameter beam and SLADS reconstructed the image sampling 31% of the total volume and only 9% of the interior of the crystal greatly reducing the X-ray dosage on the crystal. Furthermore, by usingin situtwo-photon-excited fluorescence microscopy measurements as a surrogate for diffraction imaging with a 1 µm-diameter beam, the SLADS algorithm enabled image reconstruction from a 7% sampling of the total volume and 12% sampling of the interior of the crystal. When implemented into the beamline at Argonne National Laboratory, without ground-truth images, an acceptable reconstruction was obtained with 3% of the image sampled and approximately 5% of the crystal. The incorporation of SLADS into X-ray diffraction acquisitions has the potential to significantly minimize the impact of X-ray exposure on the crystal by limiting the dose and area exposed for image reconstruction and crystal positioning using data collection hardware present in most macromolecular crystallography end-stations.« less

Dynamic X-ray diffraction sampling for protein crystal positioning

DOE PAGES

Scarborough, Nicole M.; Godaliyadda, G. M. Dilshan P.; Ye, Dong Hye; ...

2017-01-01

A sparse supervised learning approach for dynamic sampling (SLADS) is described for dose reduction in diffraction-based protein crystal positioning. Crystal centering is typically a prerequisite for macromolecular diffraction at synchrotron facilities, with X-ray diffraction mapping growing in popularity as a mechanism for localization. In X-ray raster scanning, diffraction is used to identify the crystal positions based on the detection of Bragg-like peaks in the scattering patterns; however, this additional X-ray exposure may result in detectable damage to the crystal prior to data collection. Dynamic sampling, in which preceding measurements inform the next most information-rich location to probe for image reconstruction,more » significantly reduced the X-ray dose experienced by protein crystals during positioning by diffraction raster scanning. The SLADS algorithm implemented herein is designed for single-pixel measurements and can select a new location to measure. In each step of SLADS, the algorithm selects the pixel, which, when measured, maximizes the expected reduction in distortion given previous measurements. Ground-truth diffraction data were obtained for a 5 µm-diameter beam and SLADS reconstructed the image sampling 31% of the total volume and only 9% of the interior of the crystal greatly reducing the X-ray dosage on the crystal. Furthermore, by usingin situtwo-photon-excited fluorescence microscopy measurements as a surrogate for diffraction imaging with a 1 µm-diameter beam, the SLADS algorithm enabled image reconstruction from a 7% sampling of the total volume and 12% sampling of the interior of the crystal. When implemented into the beamline at Argonne National Laboratory, without ground-truth images, an acceptable reconstruction was obtained with 3% of the image sampled and approximately 5% of the crystal. The incorporation of SLADS into X-ray diffraction acquisitions has the potential to significantly minimize the impact of X-ray exposure on the crystal by limiting the dose and area exposed for image reconstruction and crystal positioning using data collection hardware present in most macromolecular crystallography end-stations.« less

Dynamic X-ray diffraction sampling for protein crystal positioning

PubMed Central

Scarborough, Nicole M.; Godaliyadda, G. M. Dilshan P.; Ye, Dong Hye; Kissick, David J.; Zhang, Shijie; Newman, Justin A.; Sheedlo, Michael J.; Chowdhury, Azhad U.; Fischetti, Robert F.; Das, Chittaranjan; Buzzard, Gregery T.; Bouman, Charles A.; Simpson, Garth J.

2017-01-01

A sparse supervised learning approach for dynamic sampling (SLADS) is described for dose reduction in diffraction-based protein crystal positioning. Crystal centering is typically a prerequisite for macromolecular diffraction at synchrotron facilities, with X-ray diffraction mapping growing in popularity as a mechanism for localization. In X-ray raster scanning, diffraction is used to identify the crystal positions based on the detection of Bragg-like peaks in the scattering patterns; however, this additional X-ray exposure may result in detectable damage to the crystal prior to data collection. Dynamic sampling, in which preceding measurements inform the next most information-rich location to probe for image reconstruction, significantly reduced the X-ray dose experienced by protein crystals during positioning by diffraction raster scanning. The SLADS algorithm implemented herein is designed for single-pixel measurements and can select a new location to measure. In each step of SLADS, the algorithm selects the pixel, which, when measured, maximizes the expected reduction in distortion given previous measurements. Ground-truth diffraction data were obtained for a 5 µm-diameter beam and SLADS reconstructed the image sampling 31% of the total volume and only 9% of the interior of the crystal greatly reducing the X-ray dosage on the crystal. Using in situ two-photon-excited fluorescence microscopy measurements as a surrogate for diffraction imaging with a 1 µm-diameter beam, the SLADS algorithm enabled image reconstruction from a 7% sampling of the total volume and 12% sampling of the interior of the crystal. When implemented into the beamline at Argonne National Laboratory, without ground-truth images, an acceptable reconstruction was obtained with 3% of the image sampled and approximately 5% of the crystal. The incorporation of SLADS into X-ray diffraction acquisitions has the potential to significantly minimize the impact of X-ray exposure on the crystal by limiting the dose and area exposed for image reconstruction and crystal positioning using data collection hardware present in most macromolecular crystallography end-stations. PMID:28009558

Dynamic X-ray diffraction sampling for protein crystal positioning.

PubMed

Scarborough, Nicole M; Godaliyadda, G M Dilshan P; Ye, Dong Hye; Kissick, David J; Zhang, Shijie; Newman, Justin A; Sheedlo, Michael J; Chowdhury, Azhad U; Fischetti, Robert F; Das, Chittaranjan; Buzzard, Gregery T; Bouman, Charles A; Simpson, Garth J

2017-01-01

A sparse supervised learning approach for dynamic sampling (SLADS) is described for dose reduction in diffraction-based protein crystal positioning. Crystal centering is typically a prerequisite for macromolecular diffraction at synchrotron facilities, with X-ray diffraction mapping growing in popularity as a mechanism for localization. In X-ray raster scanning, diffraction is used to identify the crystal positions based on the detection of Bragg-like peaks in the scattering patterns; however, this additional X-ray exposure may result in detectable damage to the crystal prior to data collection. Dynamic sampling, in which preceding measurements inform the next most information-rich location to probe for image reconstruction, significantly reduced the X-ray dose experienced by protein crystals during positioning by diffraction raster scanning. The SLADS algorithm implemented herein is designed for single-pixel measurements and can select a new location to measure. In each step of SLADS, the algorithm selects the pixel, which, when measured, maximizes the expected reduction in distortion given previous measurements. Ground-truth diffraction data were obtained for a 5 µm-diameter beam and SLADS reconstructed the image sampling 31% of the total volume and only 9% of the interior of the crystal greatly reducing the X-ray dosage on the crystal. Using in situ two-photon-excited fluorescence microscopy measurements as a surrogate for diffraction imaging with a 1 µm-diameter beam, the SLADS algorithm enabled image reconstruction from a 7% sampling of the total volume and 12% sampling of the interior of the crystal. When implemented into the beamline at Argonne National Laboratory, without ground-truth images, an acceptable reconstruction was obtained with 3% of the image sampled and approximately 5% of the crystal. The incorporation of SLADS into X-ray diffraction acquisitions has the potential to significantly minimize the impact of X-ray exposure on the crystal by limiting the dose and area exposed for image reconstruction and crystal positioning using data collection hardware present in most macromolecular crystallography end-stations.

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

DOEpatents

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

1985-04-23

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

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

DOEpatents

Green, Lanny A.; Heck, Jr., Joaquim L.

1987-01-01

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

JMFA2—a graphically interactive Java program that fits microfibril angle X-ray diffraction data

Treesearch

Steve P. Verrill; David E. Kretschmann; Victoria L. Herian

2006-01-01

X-ray diffraction techniques have the potential to decrease the time required to determine microfibril angles dramatically. In this paper, we discuss the latest version of a curve-fitting toll that permits us to reduce the time required to evaluate MFA X-ray diffraction patterns. Further, because this tool reflects the underlying physics more accurately than existing...

Microstructural and mineralogical characterization of selected shales in support of nuclear waste repository studies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lee, S.Y.; Hyder, L.K.; Alley, P.D.

1988-01-01

Five shales were examined as part of the Sedimentary Rock Program evaluation of this medium as a potential host for a US civilian nuclear waste repository. The units selected for characterization were the Chattanooga Shale from Fentress County, Tennessee; the Pierre Shale from Gregory County, South Dakota; the Green River Formation from Garfield County, Colorado; and the Nolichucky Shale and Pumpkin Valley Shale from Roane County, Tennessee. The micromorphology and structure of the shales were examined by petrographic, scanning electron, and high-resolution transmission electron microscopy. Chemical and mineralogical compositions were studied through the use of energy-dispersive x-ray, neutron activation, atomicmore » absorption, thermal, and x-ray diffraction analysis techniques. 18 refs., 12 figs., 2 tabs.« less

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

DOE PAGES

Murray, Thomas D.; Lyubimov, Artem Y.; Ogata, Craig M.; ...

2015-08-11

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 necessarymore » 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. In addition, 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.« less

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

Murray, Thomas D.; Lyubimov, Artem Y.; Ogata, Craig M.

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 necessarymore » 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. In addition, 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.« less

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

Murray, Thomas D.; Lyubimov, Artem Y.; Ogata, Craig M.

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 (<2µl) 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 tomore » 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 (10–15µm) loaded into the chips yielded a complete, high-resolution (<1.6Å) 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.« less

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

PubMed Central

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

2015-01-01

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. PMID:26457423

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

PubMed Central

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

2010-01-01

X-ray diffraction microscopy complements other x-ray microscopy methods by being free of lens-imposed radiation dose and resolution limits, and it allows for high-resolution imaging of biological specimens too thick to be viewed by electron microscopy. We report here the highest resolution (11–13 nm) x-ray diffraction micrograph of biological specimens, and a demonstration of molecular-specific gold labeling at different depths within cells via through-focus propagation of the reconstructed wavefield. The lectin concanavalin A conjugated to colloidal gold particles was used to label the α-mannan sugar in the cell wall of the yeast Saccharomyces cerevisiae. Cells were plunge-frozen in liquid ethane and freeze-dried, after which they were imaged whole using x-ray diffraction microscopy at 750 eV photon energy. PMID:20368463

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

DOE PAGES

Nelson, Johanna; Huang, Xiaojing; Steinbrener, Jan; ...

2010-04-20

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

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

PubMed

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

2013-04-22

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

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

PubMed Central

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

2014-01-01

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

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tsusaka, Y., E-mail: tsusaka@sci.u-hyogo.ac.jp; Takano, H.; Takeda, S.

2016-02-15

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

Incorporation of interfacial roughness into recursion matrix formalism of dynamical X-ray diffraction in multilayers and superlattices.

PubMed

Lobach, Ihar; Benediktovitch, Andrei; Ulyanenkov, Alexander

2017-06-01

Diffraction in multilayers in the presence of interfacial roughness is studied theoretically, the roughness being considered as a transition layer. Exact (within the framework of the two-beam dynamical diffraction theory) differential equations for field amplitudes in a crystalline structure with varying properties along its surface normal are obtained. An iterative scheme for approximate solution of the equations is developed. The presented approach to interfacial roughness is incorporated into the recursion matrix formalism in a way that obviates possible numerical problems. Fitting of the experimental rocking curve is performed in order to test the possibility of reconstructing the roughness value from a diffraction scan. The developed algorithm works substantially faster than the traditional approach to dealing with a transition layer (dividing it into a finite number of thin lamellae). Calculations by the proposed approach are only two to three times longer than calculations for corresponding structures with ideally sharp interfaces.

Multiple defocused coherent diffraction imaging: method for simultaneously reconstructing objects and probe using X-ray free-electron lasers.

PubMed

Hirose, Makoto; Shimomura, Kei; Suzuki, Akihiro; Burdet, Nicolas; Takahashi, Yukio

2016-05-30

The sample size must be less than the diffraction-limited focal spot size of the incident beam in single-shot coherent X-ray diffraction imaging (CXDI) based on a diffract-before-destruction scheme using X-ray free electron lasers (XFELs). This is currently a major limitation preventing its wider applications. We here propose multiple defocused CXDI, in which isolated objects are sequentially illuminated with a divergent beam larger than the objects and the coherent diffraction pattern of each object is recorded. This method can simultaneously reconstruct both objects and a probe from the coherent X-ray diffraction patterns without any a priori knowledge. We performed a computer simulation of the prposed method and then successfully demonstrated it in a proof-of-principle experiment at SPring-8. The prposed method allows us to not only observe broad samples but also characterize focused XFEL beams.

Angular rheology study of colloidal nanocrystals using Coherent X-ray Diffraction

NASA Astrophysics Data System (ADS)

Liang, Mengning; Harder, Ross; Robinson, Ian

2007-03-01

A new method using coherent x-ray diffraction provides a way to investigate the rotational motion of a colloidal suspension of crystals in real time. Coherent x-ray diffraction uses the long coherence lengths of synchrotron sources to illuminate a nanoscale particle coherently over its spatial dimensions. The penetration of high energy x-rays into various media allows for in-situ measurements making it ideal for suspensions. This technique has been used to image the structure of nanocrystals for some time but also has the capability of providing information about the orientation and dynamics of crystals. The particles are imaged in a specific diffraction condition allowing us to determine their orientation and observe how they rotate in real time with exceptional resolution. Such sensitivity allows for the study of rotational Brownian motion of nanocrystals in various suspensions and conditions. We present a study of the angular rheology of alumina and TiO2 colloidal nanocrystals in media using coherent x-ray diffraction.

Characterization of polycrystalline materials using synchrotron X-ray imaging and diffraction techniques

NASA Astrophysics Data System (ADS)

Ludwig, W.; King, A.; Herbig, M.; Reischig, P.; Marrow, J.; Babout, L.; Lauridsen, E. M.; Proudhon, H.; Buffière, J. Y.

2010-12-01

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

Quantitative analysis of thoria phase in Th-U alloys using diffraction studies

NASA Astrophysics Data System (ADS)

Thakur, Shital; Krishna, P. S. R.; Shinde, A. B.; Kumar, Raj; Roy, S. B.

2017-05-01

In the present study the quantitative phase analysis of Th-U alloys in bulk form namely Th-52 wt% U and Th-3wt%U has been performed over the data obtained from both X ray diffraction and neutron diffraction technique using Rietveld method of FULLPROF software. Quantifying thoria (ThO2) phase present in bulk of the sample is limited due to surface oxidation and low penetration of x rays in high Z material. Neutron diffraction study probing bulk of the samples has been presented in comparison with x-ray diffraction study.

Mobility of rare earth elements in mine drainage: Influence of iron oxides, carbonates, and phosphates.

PubMed

Edahbi, Mohamed; Plante, Benoît; Benzaazoua, Mostafa; Ward, Matthew; Pelletier, Mia

2018-05-01

The geochemical behavior of rare earth elements (REE) was investigated using weathering cells. The influence of sorption and precipitation on dissolved REE mobility and fractionation is evaluated using synthetic iron-oxides, carbonates, and phosphates. Sorption cell tests are conducted on the main lithologies of the expected waste rocks from the Montviel deposit. The sorbed materials are characterized using a scanning electron microscope (SEM) equipped with a microanalysis system (energy dispersive spectroscopy EDS) (SEM-EDS), X-ray diffraction (XRD), and X-ray absorption near edge structure (XANES) in order to understand the effect of the synthetic minerals on REE mobility. The results confirm that sorption and precipitation control the mobility and fractionation of REE. The main sorbent phases are the carbonates, phosphates (present as accessory minerals in the Montviel waste rocks), and iron oxides (main secondary minerals generated upon weathering of the Montviel lithologies). The XANES results show that REE are present as trivalent species after weathering. Thermodynamic equilibrium calculations results using Visual Minteq suggest that REE could precipitate as secondary phosphates (REEPO 4 ). Copyright © 2018 Elsevier Ltd. All rights reserved.

The early growth and interface of YBa 2Cu 3O y thin films deposited on YSZ substrates

NASA Astrophysics Data System (ADS)

Gao, J.; Tang, W. H.; Yau, C. Y.

2001-11-01

Epitaxial thin films of YBa 2Cu 3O y (YBCO) have been prepared on yttrium-stabilized zirconia substrates with and without a buffer layer. The early growth, crystallinity and surface morphology of these thin films have been characterized by X-ray diffraction, rocking curves, scanning electron microscope, in situ conductance measurements, and surface step profiler. The full width at half maximum of the ( 0 0 5 ) peak of rocking curve was found to be less than 0.1°. Over a wide scanning range of 2000 μm the average surface roughness is just 5 nm, indicating very smooth films. Grazing incident X-ray reflection and positron annihilation spectroscopy shows well-defined interfaces between layers and substrate. By applying a new Eu 2CuO 4 (ECO) buffer layer the initial formation of YBCO appears to grow layer-by-layer rather than the typical island growth mode. The obtained results reveal significant improvements at the early formation and crystallinity of YBCO by using the 214-T ‧ ECO as a buffer layer.

Selenium single-wavelength anomalous diffraction de novo phasing using an X-ray-free electron laser

DOE PAGES

Hunter, Mark S.; Yoon, Chun Hong; DeMirci, Hasan; ...

2016-11-04

Structural information about biological macromolecules near the atomic scale provides important insight into the functions of these molecules. To date, X-ray crystallography has been the predominant method used for macromolecular structure determination. However, challenges exist when solving structures with X-rays, including the phase problem and radiation damage. X-ray-free electron lasers (X-ray FELs) have enabled collection of diffraction information before the onset of radiation damage, yet the majority of structures solved at X-ray FELs have been phased using external information via molecular replacement. De novo phasing at X-ray FELs has proven challenging due in part to per-pulse variations in intensity andmore » wavelength. Here we report the solution of a selenobiotinyl-streptavidin structure using phases obtained by the anomalous diffraction of selenium measured at a single wavelength (Se-SAD) at the Linac Coherent Light Source. Finally, our results demonstrate Se-SAD, routinely employed at synchrotrons for novel structure determination, is now possible at X-ray FELs.« less

Macromolecular structures probed by combining single-shot free-electron laser diffraction with synchrotron coherent X-ray imaging.

PubMed

Gallagher-Jones, Marcus; Bessho, Yoshitaka; Kim, Sunam; Park, Jaehyun; Kim, Sangsoo; Nam, Daewoong; Kim, Chan; Kim, Yoonhee; Noh, Do Young; Miyashita, Osamu; Tama, Florence; Joti, Yasumasa; Kameshima, Takashi; Hatsui, Takaki; Tono, Kensuke; Kohmura, Yoshiki; Yabashi, Makina; Hasnain, S Samar; Ishikawa, Tetsuya; Song, Changyong

2014-05-02

Nanostructures formed from biological macromolecular complexes utilizing the self-assembly properties of smaller building blocks such as DNA and RNA hold promise for many applications, including sensing and drug delivery. New tools are required for their structural characterization. Intense, femtosecond X-ray pulses from X-ray free-electron lasers enable single-shot imaging allowing for instantaneous views of nanostructures at ambient temperatures. When combined judiciously with synchrotron X-rays of a complimentary nature, suitable for observing steady-state features, it is possible to perform ab initio structural investigation. Here we demonstrate a successful combination of femtosecond X-ray single-shot diffraction with an X-ray free-electron laser and coherent diffraction imaging with synchrotron X-rays to provide an insight into the nanostructure formation of a biological macromolecular complex: RNA interference microsponges. This newly introduced multimodal analysis with coherent X-rays can be applied to unveil nano-scale structural motifs from functional nanomaterials or biological nanocomplexes, without requiring a priori knowledge.

Crystal growth, structural, low temperature thermoluminescence and mechanical properties of cubic fluoroperovskite single crystal (LiBaF3)

NASA Astrophysics Data System (ADS)

Daniel, D. Joseph; Ramasamy, P.; Ramaseshan, R.; Kim, H. J.; Kim, Sunghwan; Bhagavannarayana, G.; Cheon, Jong-Kyu

2017-10-01

Polycrystalline compounds of LiBaF3 were synthesized using conventional solid state reaction route and the phase purity was confirmed using powder X-ray diffraction technique. Using vertical Bridgman technique single crystal was grown from melt. Rocking curve measurements have been carried out to study the structural perfection of the grown crystal. The single peak of diffraction curve clearly reveals that the grown crystal was free from the structural grain boundaries. The low temperature thermoluminescence of the X-ray irradiated sample has been analyzed and found four distinguishable peaks having maximum temperatures at 18, 115, 133 and 216 K. Activation energy (E) and frequency factor (s) for the individual peaks have been studied using Peak shape method and the computerized curve fitting method combining with the Tmax- TStop procedure. Nanoindentation technique was employed to study the mechanical behaviour of the crystal. The indentation modulus and Vickers hardness of the grown crystal have values of 135.15 GPa and 680.81 respectively, under the maximum indentation load of 10 mN.

Effect of low NH3 flux towards high quality semi-polar (11-22) GaN on m-plane sapphire via MOCVD

NASA Astrophysics Data System (ADS)

Omar, Al-Zuhairi; Shuhaimi Bin Abu Bakar, Ahmad; Makinudin, Abdullah Haaziq Ahmad; Khudus, Muhammad Imran Mustafa Abdul; Azman, Adreen; Kamarundzaman, Anas; Supangat, Azzuliani

2018-05-01

The effect of ammonia flux towards the quality of the semi-polar (11-22) gallium nitride thin film on m-plane (10-10) sapphire is presented. Semi-polar (11-22) gallium nitride epi-layers were obtained using a two-step growth method, consisting of high temperature aluminum nitride followed by gallium nitride via metal organic chemical vapor deposition. The surface morphology analysis via field emission scanning electron microscopy and atomic force microscopy of the semi-polar (11-22) gallium nitride has shown that low ammonia flux promotes two-dimensional growth with low surface roughness of 4.08 nm. A dominant diffraction peak of (11-22) gallium nitride was also observed via X-ray diffraction upon utilizing low ammonia flux. The on- and off-axis X-ray rocking curve measurements illustrate the enhancement of the crystal quality, which might result from the reduction of the basal stacking faults and perfect dislocation. The full width half maximum values were reduced by at least 15% for both on- and off-axis measurements.

In-situ cyclic pulse annealing of InN on AlN/Si during IR-lamp-heated MBE growth

NASA Astrophysics Data System (ADS)

Suzuki, Akira; Bungi, Yu; Araki, Tsutomu; Nanishi, Yasushi; Mori, Yasuaki; Yamamoto, Hiroaki; Harima, Hiroshi

2009-05-01

To improve crystal quality of InN, an in-situ cyclic rapid pulse annealing during growth was carried out using infrared-lamp-heated molecular beam epitaxy. A cycle of 4 min growth of InN at 400 °C and 3 s pulse annealing at a higher temperature was repeated 15 times on AlN on Si substrate. Annealing temperatures were 550, 590, 620, and 660 °C. The back of Si was directly heated by lamp irradiation through a quartz rod. A total InN film thickness was about 200 nm. With increasing annealing temperature up to 620 °C, crystal grain size by scanning electron microscope showed a tendency to increase, while widths of X-ray diffraction rocking curve of (0 0 0 2) reflection and E 2 (high) mode peak of Raman scattering spectra decreased. A peak of In (1 0 1) appeared in X-ray diffraction by annealing higher than 590 °C, and In droplets were found on the surface by annealing at 660 °C.

Exploration of New Principles in Spintronics Based on Topological Insulators (Option 1)

DTIC Science & Technology

2012-05-14

on the surface and found that our crystals are exceedingly homogeneous (Supplementary Information). The persistently narrow X - ray diffraction peaks...modified Bridgman method (see Supplementary Information for details). X - ray diffraction measurements indicated the monotonic shrinkage of a and c axis...and annealing at that temperature for 4 days. X - ray diffraction analyses confirmed that all the samples have the same crystal structure (R 3m

Efficient modeling of Bragg coherent x-ray nanobeam diffraction

DOE PAGES

Hruszkewycz, S. O.; Holt, M. V.; Allain, M.; ...

2015-07-02

X-ray Bragg diffraction experiments that utilize tightly focused coherent beams produce complicated Bragg diffraction patterns that depend on scattering geometry, characteristics of the sample, and properties of the x-ray focusing optic. In this paper, we use a Fourier-transform-based method of modeling the 2D intensity distribution of a Bragg peak and apply it to the case of thin films illuminated with a Fresnel zone plate in three different Bragg scattering geometries. Finally, the calculations agree well with experimental coherent diffraction patterns, demonstrating that nanodiffraction patterns can be modeled at nonsymmetric Bragg conditions with this approach—a capability critical for advancing nanofocused x-raymore » diffraction microscopy.« less

HPHT growth and x-ray characterization of high-quality type IIa diamond.

PubMed

Burns, R C; Chumakov, A I; Connell, S H; Dube, D; Godfried, H P; Hansen, J O; Härtwig, J; Hoszowska, J; Masiello, F; Mkhonza, L; Rebak, M; Rommevaux, A; Setshedi, R; Van Vaerenbergh, P

2009-09-09

The trend in synchrotron radiation (x-rays) is towards higher brilliance. This may lead to a very high power density, of the order of hundreds of watts per square millimetre at the x-ray optical elements. These elements are, typically, windows, polarizers, filters and monochromators. The preferred material for Bragg diffracting optical elements at present is silicon, which can be grown to a very high crystal perfection and workable size as well as rather easily processed to the required surface quality. This allows x-ray optical elements to be built with a sufficient degree of lattice perfection and crystal processing that they may preserve transversal coherence in the x-ray beam. This is important for the new techniques which include phase-sensitive imaging experiments like holo-tomography, x-ray photon correlation spectroscopy, coherent diffraction imaging and nanofocusing. Diamond has a lower absorption coefficient than silicon, a better thermal conductivity and lower thermal expansion coefficient which would make it the preferred material if the crystal perfection (bulk and surface) could be improved. Synthetic HPHT-grown (high pressure, high temperature) type Ib material can readily be produced in the necessary sizes of 4-8 mm square and with a nitrogen content of typically a few hundred parts per million. This material has applications in the less demanding roles such as phase plates: however, in a coherence-preserving beamline, where all elements must be of the same high quality, its quality is far from sufficient. Advances in HPHT synthesis methods have allowed the growth of type IIa diamond crystals of the same size as type Ib, but with substantially lower nitrogen content. Characterization of this high purity type IIa material has been carried out with the result that the crystalline (bulk) perfection of some of the HPHT-grown materials is approaching the quality required for the more demanding applications such as imaging applications and imaging applications with coherence preservation. The targets for further development of the type IIa diamond are size, crystal perfection, as measured by the techniques of white beam and monochromatic x-ray diffraction imaging (historically called x-ray topography), and also surface quality. Diamond plates extracted from the cubic growth sector furthest from the seed of the new low strain material produces no measurable broadening of the x-ray rocking curve width. One measures essentially the crystal reflectivity as defined by the intrinsic reflectivity curve (Darwin curve) width of a perfect crystal. In these cases the more sensitive technique of plane wave topography has been used to establish a local upper limit of the strain at the level of an 'effective misorientation' of 10(-7) rad.

HiSPoD: a program for high-speed polychromatic X-ray diffraction experiments and data analysis on polycrystalline samples

DOE PAGES

Sun, Tao; Fezzaa, Kamel

2016-06-17

Here, a high-speed X-ray diffraction technique was recently developed at the 32-ID-B beamline of the Advanced Photon Source for studying highly dynamic, yet non-repeatable and irreversible, materials processes. In experiments, the microstructure evolution in a single material event is probed by recording a series of diffraction patterns with extremely short exposure time and high frame rate. Owing to the limited flux in a short pulse and the polychromatic nature of the incident X-rays, analysis of the diffraction data is challenging. Here, HiSPoD, a stand-alone Matlab-based software for analyzing the polychromatic X-ray diffraction data from polycrystalline samples, is described. With HiSPoD,more » researchers are able to perform diffraction peak indexing, extraction of one-dimensional intensity profiles by integrating a two-dimensional diffraction pattern, and, more importantly, quantitative numerical simulations to obtain precise sample structure information.« less

Molybdenum cell for x-ray diffraction measurements of fluid alkali metals at high temperatures and high pressures

NASA Astrophysics Data System (ADS)

Matsuda, Kazuhiro; Tamura, Kozaburo; Katoh, Masahiro; Inui, Masanori

2004-03-01

We have developed a sample cell for x-ray diffraction measurements of fluid alkali metals at high temperatures and high pressures. All parts of the cell are made of molybdenum which is resistant to the chemical corrosion of alkali metals. Single crystalline molybdenum disks electrolytically thinned down to 40 μm were used as the walls of the cell through which x rays pass. The crystal orientation of the disks was controlled in order to reduce the background from the cell. All parts of the cell were assembled and brazed together using a high-temperature Ru-Mo alloy. Energy dispersive x-ray diffraction measurements have been successfully carried out for fluid rubidium up to 1973 K and 16.2 MPa. The obtained S(Q) demonstrates the applicability of the molybdenum cell to x-ray diffraction measurements of fluid alkali metals at high temperatures and high pressures.

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

DOE PAGES

Chapman, Henry N.; Barty, Anton; Marchesini, Stefano; ...

2006-01-01

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

Enhancing resolution in coherent x-ray diffraction imaging.

PubMed

Noh, Do Young; Kim, Chan; Kim, Yoonhee; Song, Changyong

2016-12-14

Achieving a resolution near 1 nm is a critical issue in coherent x-ray diffraction imaging (CDI) for applications in materials and biology. Albeit with various advantages of CDI based on synchrotrons and newly developed x-ray free electron lasers, its applications would be limited without improving resolution well below 10 nm. Here, we review the issues and efforts in improving CDI resolution including various methods for resolution determination. Enhancing diffraction signal at large diffraction angles, with the aid of interference between neighboring strong scatterers or templates, is reviewed and discussed in terms of increasing signal-to-noise ratio. In addition, we discuss errors in image reconstruction algorithms-caused by the discreteness of the Fourier transformations involved-which degrade the spatial resolution, and suggest ways to correct them. We expect this review to be useful for applications of CDI in imaging weakly scattering soft matters using coherent x-ray sources including x-ray free electron lasers.

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

NASA Astrophysics Data System (ADS)

Eveno, Myriam; Duran, Adrian; Castaing, Jacques

2010-09-01

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

X-ray fractography on fatigue fractured surface of austenitic stainless steel

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yajima, Zenjiro; Tokuyama, Hideki; Kibayashi, Yasuo

1995-12-31

X-ray diffraction observation of the material internal structure beneath fracture surfaces provide fracture analysis with useful information to investigate the conditions and mechanisms of fracture. X-ray fractography is a generic name given to this technique. In the present study, X-ray fractography was applied to fatigue fracture surfaces of austenitic stainless steel (AISI 304) which consisted of solution treatment. The fatigue tests were carried out on compact tension (CT) specimens. The plastic strain on the fracture surface was estimated from measuring the line broadening of X-ray diffraction profiles. The line broadening of X-ray diffraction profiles was measured on and beneath fatiguemore » fracture surfaces. The depth of the plastic zone left on fracture surfaces was evaluated from the line broadening. The results are discussed on the basis of fracture mechanics.« less

Toward in situ x-ray diffraction imaging at the nanometer scale

NASA Astrophysics Data System (ADS)

Zatsepin, Nadia A.; Dilanian, Ruben A.; Nikulin, Andrei Y.; Gable, Brian M.; Muddle, Barry C.; Sakata, Osami

2008-08-01

We present the results of preliminary investigations determining the sensitivity and applicability of a novel x-ray diffraction based nanoscale imaging technique, including simulations and experiments. The ultimate aim of this nascent technique is non-destructive, bulk-material characterization on the nanometer scale, involving three dimensional image reconstructions of embedded nanoparticles and in situ sample characterization. The approach is insensitive to x-ray coherence, making it applicable to synchrotron and laboratory hard x-ray sources, opening the possibility of unprecedented nanometer resolution with the latter. The technique is being developed with a focus on analyzing a technologically important light metal alloy, Al-xCu (where x is 2.0-5.0 %wt). The mono- and polycrystalline samples contain crystallographically oriented, weakly diffracting Al2Cu nanoprecipitates in a sparse, spatially random dispersion within the Al matrix. By employing a triple-axis diffractometer in the non-dispersive setup we collected two-dimensional reciprocal space maps of synchrotron x-rays diffracted from the Al2Cu nanoparticles. The intensity profiles of the diffraction peaks confirmed the sensitivity of the technique to the presence and orientation of the nanoparticles. This is a fundamental step towards in situ observation of such extremely sparse, weakly diffracting nanoprecipitates embedded in light metal alloys at early stages of their growth.

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

EPA Science Inventory

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

History and Solution of the Phase Problem in theTheory of Structure Determination of Crystals from X-ray Diffraction Experiments

ScienceCinema

Wolf, Emil [University of Rochester, Rochester, New York, United States

2017-12-09

Since the pioneering work of Max von Laue on interference and diffraction of x-rays, carried out almost 100 years ago, numerous attempts have been made to determine structures of crystalline media from x-ray diffraction experiments. The usefulness of all of them has been limited by the inability of measuring phases of the diffracted beams. In this talk, the most important research carried out in this field will be reviewed and a recently obtained solution of the phase problem will be presented.

Dissolution-Driven Permeability Reduction of a Fractured Carbonate Caprock

PubMed Central

Ellis, Brian R.; Fitts, Jeffrey P.; Bromhal, Grant S.; McIntyre, Dustin L.; Tappero, Ryan; Peters, Catherine A.

2013-01-01

Abstract Geochemical reactions may alter the permeability of leakage pathways in caprocks, which serve a critical role in confining CO2 in geologic carbon sequestration. A caprock specimen from a carbonate formation in the Michigan sedimentary Basin was fractured and studied in a high-pressure core flow experiment. Inflowing brine was saturated with CO2 at 40°C and 10 MPa, resulting in an initial pH of 4.6, and had a calcite saturation index of −0.8. Fracture permeability decreased during the experiment, but subsequent analyses did not reveal calcite precipitation. Instead, experimental observations indicate that calcite dissolution along the fracture pathway led to mobilization of less soluble mineral particles that clogged the flow path. Analyses of core sections via electron microscopy, synchrotron-based X-ray diffraction imaging, and the first application of microbeam Ca K-edge X-ray absorption near edge structure, provided evidence that these occlusions were fragments from the host rock rather than secondary precipitates. X-ray computed tomography showed a significant loss of rock mass within preferential flow paths, suggesting that dissolution also removed critical asperities and caused mechanical closure of the fracture. The decrease in fracture permeability despite a net removal of material along the fracture pathway demonstrates a nonintuitive, inverse relationship between dissolution and permeability evolution in a fractured carbonate caprock. PMID:23633894

XRayView: a teaching aid for X-ray crystallography.

PubMed

Phillips, G N

1995-10-01

A software package, XRayView, has been developed that uses interactive computer graphics to introduce basic concepts of x-ray diffraction by crystals, including the reciprocal lattice, the Ewald sphere construction, Laue cones, the wavelength dependence of the reciprocal lattice, primitive and centered lattices and systematic extinctions, rotation photography. Laue photography, space group determination and Laue group symmetry, and the alignment of crystals by examination of reciprocal space. XRayView is designed with "user-friendliness" in mind, using pull-down menus to control the program. Many of the experiences of using real x-ray diffraction equipment to examine crystalline diffraction can be simulated. Exercises are available on-line to guide the users through many typical x-ray diffraction experiments.

Application of MEMS-based x-ray optics as tuneable nanosecond choppers

NASA Astrophysics Data System (ADS)

Chen, Pice; Walko, Donald A.; Jung, Il Woong; Li, Zhilong; Gao, Ya; Shenoy, Gopal K.; Lopez, Daniel; Wang, Jin

2017-08-01

Time-resolved synchrotron x-ray measurements often rely on using a mechanical chopper to isolate a set of x-ray pulses. We have started the development of micro electromechanical systems (MEMS)-based x-ray optics, as an alternate method to manipulate x-ray beams. In the application of x-ray pulse isolation, we recently achieved a pulse-picking time window of half a nanosecond, which is more than 100 times faster than mechanical choppers can achieve. The MEMS device consists of a comb-drive silicon micromirror, designed for efficiently diffracting an x-ray beam during oscillation. The MEMS devices were operated in Bragg geometry and their oscillation was synchronized to x-ray pulses, with a frequency matching subharmonics of the cycling frequency of x-ray pulses. The microscale structure of the silicon mirror in terms of the curvature and the quality of crystallinity ensures a narrow angular spread of the Bragg reflection. With the discussion of factors determining the diffractive time window, this report showed our approaches to narrow down the time window to half a nanosecond. The short diffractive time window will allow us to select single x-ray pulse out of a train of pulses from synchrotron radiation facilities.

Fabrication of high-resolution x-ray diffractive optics at King's College London

NASA Astrophysics Data System (ADS)

Charalambous, Pambos S.; Anastasi, Peter A. F.; Burge, Ronald E.; Popova, Katia

1995-09-01

The fabrication of high resolution x-ray diffractive optics, and Fresnel zone plates (ZPs) in particular, is a very demanding multifaceted technological task. The commissioning of more (and brighter) synchrotron radiation sources, has increased the number of x-ray imaging beam lines world wide. The availability of cheaper and more effective laboratory x-ray sources, has further increased the number of laboratories involved in x-ray imaging. The result is an ever increasing demand for x-ray optics with a very wide range of specifications, reflecting the particular type of x-ray imaging performed at different laboratories. We have been involved in all aspects of high resolution nanofabrication for a number of years, and we have explored many different methods of lithography, which, although unorthodox, open up possibilities, and increase our flexibility for the fabrication of different diffractive optical elements, as well as other types of nanostructures. The availability of brighter x-ray sources, means that the diffraction efficiency of the ZPs is becoming of secondary importance, a trend which will continue in the future. Resolution, however, is important and will always remain so. Resolution is directly related to the accuracy af pattern generation, as well as the ability to draw fine lines. This is the area towards which we have directed most of our efforts so far.

Two-photon x-ray diffraction

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stohr, J.

The interference pattern of a circular photon source has long been used to define the optical diffraction limit. Here we show the breakdown of conventional x-ray diffraction theory for the fundamental case of a “source”, consisting of a back-illuminated thin film in a circular aperture. When the conventional spontaneous x-ray scattering by atoms in the film is replaced at high incident intensity by stimulated resonant scattering, the film becomes the source of cloned photon twins and the diffraction pattern becomes self-focused beyond the diffraction limit. Furthermore, the case of cloned photon pairs is compared to and distinguished from entangled photonmore » pairs or biphotons.« less

Two-photon x-ray diffraction

DOE PAGES

Stohr, J.

2017-01-11

The interference pattern of a circular photon source has long been used to define the optical diffraction limit. Here we show the breakdown of conventional x-ray diffraction theory for the fundamental case of a “source”, consisting of a back-illuminated thin film in a circular aperture. When the conventional spontaneous x-ray scattering by atoms in the film is replaced at high incident intensity by stimulated resonant scattering, the film becomes the source of cloned photon twins and the diffraction pattern becomes self-focused beyond the diffraction limit. Furthermore, the case of cloned photon pairs is compared to and distinguished from entangled photonmore » pairs or biphotons.« less

Characterization of X80 and X100 Microalloyed Pipeline Steel Using Quantitative X-ray Diffraction

NASA Astrophysics Data System (ADS)

Wiskel, J. B.; Li, X.; Ivey, D. G.; Henein, H.

2018-06-01

Quantitative X-ray diffraction characterization of four (4) X80 and three (3) X100 microalloyed steels was undertaken. The effect of through-thickness position, processing parameters, and composition on the measured crystallite size, microstrain, and J index (relative magnitude of crystallographic texture) was determined. Microstructure analysis using optical microscopy, scanning electron microscopy, transmission electron microscopy, and electron-backscattered diffraction was also undertaken. The measured value of microstrain increased with increasing alloy content and decreasing cooling interrupt temperature. Microstructural features corresponding to crystallite size in the X80 steels were both above and below the detection limit for quantitative X-ray diffraction. The X100 steels consistently exhibited microstructure features below the crystallite size detection limit. The yield stress of each steel increased with increasing microstrain. The increase in microstrain from X80 to X100 is also associated with a change in microstructure from predominantly polygonal ferrite to bainitic ferrite.

Process parameters, orientation, and functional properties of melt-processed bulk Y-Ba-Cu-O superconductors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zakharchenko, I.V.; Terryll, K.M.; Rao, K.V.

1995-03-01

This study compared the microstructure, texturing, and functional properties (critical currents) of YBa{sub 2}Cu{sub 3}O{sub 7{minus}x}-based bulk pellets that were prepared by the quench-melt-growth-process (QMGP), melt-textured growth (MTG), and conventional solid-state reaction (SSR) approaches. Using two X-ray diffraction (XRD) methods, {theta}-2{theta}, and rocking curves, the authors found that the individual grains of two melt-processed pellets exhibited remarkable preferred orientational alignment (best rocking curve width = 3.2{degree}). However, the direction of the preferred orientation among the grains was random. Among the three types of bulk materials studied, the QMGP sample was found to have the best J{sub c} values, {approx} 4,500more » A/cm{sup 2} at 77 K in a field of 2 kG, as determined from SQUID magnetic data.« less

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

PubMed

Hrdý, Jaromír; Mikulík, Petr; Oberta, Peter

2011-03-01

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

Enhanced stabilization of Pb, Zn, and Cd in contaminated soils using oxalic acid-activated phosphate rocks.

PubMed

Zhang, Zhuo; Guo, Guanlin; Wang, Mei; Zhang, Jia; Wang, Zhixin; Li, Fasheng; Chen, Honghan

2018-01-01

Phosphate amendments, especially phosphate rock (PR), are one of the most commonly used materials to stabilize heavy metals in contaminated soils. However, most of PR reserve consists of low-grade ore, which limits the efficiency of PR for stabilizing heavy metals. This study was to enhance the stabilization of heavy metals through improving the available phosphorous (P) release of PR by oxalic acid activation. Raw PR and activated PR (APR) were characterized by scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDS), X-ray powder diffraction (XRD), Brunauer-Emmett-Teller (BET) surface analysis, and laser diffraction to determine the changes of structure and composition of APR. The stabilization effectiveness of lead (Pb), zinc (Zn), and cadmium (Cd) in soils by APR was investigated through toxicity leaching test and speciation analysis. The results indicated that after treatment by oxalic acid, (1) the crystallinity of the fluorapatite phase of PR transformed into the weddellite phase; (2) the surface area of PR increased by 37%; (3) the particle size of PR became homogenized (20-70 μm); and (4) the available P content in PR increased by 22 times. These changes of physicochemical characteristics of PR induced that APR was more effective to transform soil heavy metals from the non-residual fraction to the residual fraction and enhance the stabilization efficiency of Pb, Zn, and Cd than PR. These results are significant for the future use of low-grade PR to stabilize heavy metals.

Silicate Carbonation in Supercritical CO2 Containing Dissolved H2O: An in situ High Pressure X-Ray Diffraction Study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schaef, Herbert T.; Miller, Quin RS; Thompson, Christopher J.

2013-06-30

Technological advances have been significant in recent years for managing environmentally harmful emissions (mostly CO2) resulting from combustion of fossil fuels. Deep underground geologic formations are emerging as reasonable options for long term storage of CO2 but mechanisms controlling rock and mineral stability in contact with injected supercritical fluids containing water are relatively unknown. In this paper, we discuss mineral transformation reactions occurring between supercritical CO2 containing water and the silicate minerals forsterite (Mg2SiO4), wollastonite (CaSiO3), and enstatite (MgSiO3). This study utilizes newly developed in situ high pressure x-ray diffraction (HXRD) and in situ infra red (IR) to examine mineralmore » transformation reactions. Forsterite and enstatite were selected as they are important minerals present in igneous and mafic rocks and have been the subject of a large number of aqueous dissolution studies that can be compared with non-aqueous fluid tests in this study. Wollastonite, classified as a pyroxenoid (similar to a pyroxene), was chosen as a suitably fast reacting proxy for examining silicate carbonation processes associated with a wet scCO2 fluid as related to geologic carbon sequestration. The experiments were conducted under modest pressures (90 to 160 bar), temperatures between 35° to 70° C, and varying concentrations of dissolved water. Under these conditions scCO2 contains up to 3,500 ppm dissolved water.« less

Room Temperature Elastic Moduli and Vickers Hardness of Hot-Pressed LLZO Cubic Garnet

DTIC Science & Technology

2012-01-01

polishing compounds, Leco, St. Joseph, MI). X - ray diffraction and scanning electron microscopy (SEM) The microstructure of the hot-pressed specimens...was examined on uncoated fracture surfaces by SEM with an accelerating voltage of 1 and 3 kV. Phase purity was evaluated from X - ray diffraction data...the micro- structure appeared to be homogenous for the two hot- pressed LLZO specimens included in this study (Fig. 1). X - ray diffraction confirmed that

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

DOEpatents

Berman, Robert M.; Cohen, Isadore

1990-01-01

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

Crystal structure and density of helium to 232 kbar

NASA Technical Reports Server (NTRS)

Mao, H. K.; Wu, Y.; Jephcoat, A. P.; Hemley, R. J.; Bell, P. M.; Bassett, W. A.

1988-01-01

The properties of helium and hydrogen at high pressure are topics of great interest to the understanding of planetary interiors. These materials constitute 95 percent of the entire solar system. A technique was presented for the measurement of X-ray diffraction from single-crystals of low-Z condenses gases in a diamond-anvil cell at high pressure. The first such single-crystal X-ray diffraction measurements on solid hydrogen to 26.5 GPa were presented. The application of this technique to the problem of the crystal structure, equation of state, and phase diagram of solid helium is reported. Crucial for X-ray diffraction studies of these materials is the use of a synchrotron radiation source which provides high brillance, narrow collimation of the incident and diffracted X-ray beams to reduce the background noise, and energy-dispersive diffraction techniques with polychromatic (white) radiation, which provides high detection efficiency.

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

Veluraja, K., E-mail: veluraja@msuniv.ac.in; Vennila, K.N.; Umamakeshvari, K.

Research highlights: {yields} Techniques to get oriented mucin fibre. {yields} X-ray fibre diffraction pattern for mucin. {yields} Molecular modeling of mucin based on X-ray fibre diffraction pattern. -- Abstract: The basic understanding of the three dimensional structure of mucin is essential to understand its physiological function. Technology has been developed to achieve orientated porcine stomach mucin molecules. X-ray fiber diffraction of partially orientated porcine stomach mucin molecules show d-spacing signals at 2.99, 4.06, 4.22, 4.7, 5.37 and 6.5 A. The high intense d-spacing signal at 4.22 A is attributed to the antiparallel {beta}-sheet structure identified in the fraction of themore » homology modeled mucin molecule (amino acid residues 800-980) using Nidogen-Laminin complex structure as a template. The X-ray fiber diffraction signal at 6.5 A reveals partial organization of oligosaccharides in porcine stomach mucin. This partial structure of mucin will be helpful in establishing a three dimensional structure for the whole mucin molecule.« less

A nearly on-axis spectroscopic system for simultaneously measuring UV-visible absorption and X-ray diffraction in the SPring-8 structural genomics beamline.

PubMed

Sakaguchi, Miyuki; Kimura, Tetsunari; Nishida, Takuma; Tosha, Takehiko; Sugimoto, Hiroshi; Yamaguchi, Yoshihiro; Yanagisawa, Sachiko; Ueno, Go; Murakami, Hironori; Ago, Hideo; Yamamoto, Masaki; Ogura, Takashi; Shiro, Yoshitsugu; Kubo, Minoru

2016-01-01

UV-visible absorption spectroscopy is useful for probing the electronic and structural changes of protein active sites, and thus the on-line combination of X-ray diffraction and spectroscopic analysis is increasingly being applied. Herein, a novel absorption spectrometer was developed at SPring-8 BL26B2 with a nearly on-axis geometry between the X-ray and optical axes. A small prism mirror was placed near the X-ray beamstop to pass the light only 2° off the X-ray beam, enabling spectroscopic analysis of the X-ray-exposed volume of a crystal during X-ray diffraction data collection. The spectrometer was applied to NO reductase, a heme enzyme that catalyzes NO reduction to N2O. Radiation damage to the heme was monitored in real time during X-ray irradiation by evaluating the absorption spectral changes. Moreover, NO binding to the heme was probed via caged NO photolysis with UV light, demonstrating the extended capability of the spectrometer for intermediate analysis.

Investigating the Effects of Low Temperature Annealing of Amorphous Corrosion Resistant Alloys.

DTIC Science & Technology

1980-11-01

Ray Diffraction.................................................... 6 Differential Scanning Calorimetry....................................... 9...17 LIST OF FIGURES Figure 1. X- Ray Diffraction Results From Fe32Ni 36Cr 4P 2 B Annealed for One Hour at...Various Temperatures (Cr Ka Radiation) ................................. 7 Figure 2. X- Ray Diffraction Results From FeU2NiaeCr14SieB Annealed for One

Evidence from x-ray and neutron powder diffraction patterns that the so-called icosahedral and decagonal quasicrystals of MnAl(6) and other alloys are twinned cubic crystals.

PubMed

Pauling, L

1987-06-01

It is shown that the x-ray powder diffraction patterns of rapidly quenched MnAl(6) and Mg(32)(Al,Zn)(49) and the neutron powder diffraction pattern of MnAl(6) are compatible with the proposed 820-atom primitive cubic structure [Pauling, L. (1987) Phys. Rev. Lett. 58, 365-368]. The values found for the edge of the unit cube are 23.365 A (x-ray) and 23.416 A (neutron) for MnAl(6) and 24.313 A (x-ray) for Mg(32)(Al,Zn)(49).

Evidence from x-ray and neutron powder diffraction patterns that the so-called icosahedral and decagonal quasicrystals of MnAl6 and other alloys are twinned cubic crystals

PubMed Central

Pauling, Linus

1987-01-01

It is shown that the x-ray powder diffraction patterns of rapidly quenched MnAl6 and Mg32(Al,Zn)49 and the neutron powder diffraction pattern of MnAl6 are compatible with the proposed 820-atom primitive cubic structure [Pauling, L. (1987) Phys. Rev. Lett. 58, 365-368]. The values found for the edge of the unit cube are 23.365 Å (x-ray) and 23.416 Å (neutron) for MnAl6 and 24.313 Å (x-ray) for Mg32(Al,Zn)49. PMID:16593841

High-energy X-ray diffraction using the Pixium 4700 flat-panel detector.

PubMed

Daniels, J E; Drakopoulos, M

2009-07-01

The Pixium 4700 detector represents a significant step forward in detector technology for high-energy X-ray diffraction. The detector design is based on digital flat-panel technology, combining an amorphous Si panel with a CsI scintillator. The detector has a useful pixel array of 1910 x 2480 pixels with a pixel size of 154 microm x 154 microm, and thus it covers an effective area of 294 mm x 379 mm. Designed for medical imaging, the detector has good efficiency at high X-ray energies. Furthermore, it is capable of acquiring sequences of images at 7.5 frames per second in full image mode, and up to 60 frames per second in binned region of interest modes. Here, the basic properties of this detector applied to high-energy X-ray diffraction are presented. Quantitative comparisons with a widespread high-energy detector, the MAR345 image plate scanner, are shown. Other properties of the Pixium 4700 detector, including a narrow point-spread function and distortion-free image, allows for the acquisition of high-quality diffraction data at high X-ray energies. In addition, high frame rates and shutterless operation open new experimental possibilities. Also provided are the necessary data for the correction of images collected using the Pixium 4700 for diffraction purposes.

Crystallization and preliminary X-ray diffraction analysis of a chitin-binding domain of hyperthermophilic chitinase from Pyrococcus furiosus

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nakamura, Tsutomu; Ishikawa, Kazuhiko; Hagihara, Yoshihisa

The expression, purification and preliminary X-ray diffraction studies of a chitin-binding domain of the chitinase from P. furiosus are reported. The crystallization and preliminary X-ray diffraction analysis of the chitin-binding domain of chitinase from a hyperthermophilic archaeon, Pyrococcus furiosus, are reported. The recombinant protein was prepared using an Escherichia coli overexpression system and was crystallized by the hanging-drop vapour-diffusion method. An X-ray diffraction data set was collected to 1.70 Å resolution. The crystal belonged to space group P4{sub 3}2{sub 1}2 or P4{sub 1}2{sub 1}2. The unit-cell parameters were determined to be a = b = 48.8, c = 85.0 Å.

Long-Wavelength X-Ray Diffraction and Its Applications in Macromolecular Crystallography.

PubMed

Weiss, Manfred S

2017-01-01

For many years, diffraction experiments in macromolecular crystallography at X-ray wavelengths longer than that of Cu-K α (1.54 Å) have been largely underappreciated. Effects caused by increased X-ray absorption result in the fact that these experiments are more difficult than the standard diffraction experiments at short wavelengths. However, due to the also increased anomalous scattering of many biologically relevant atoms, important additional structural information can be obtained. This information, in turn, can be used for phase determination, for substructure identification, in molecular replacement approaches, as well as in structure refinement. This chapter reviews the possibilities and the difficulties associated with such experiments, and it provides a short description of two macromolecular crystallography synchrotron beam lines dedicated to long-wavelength X-ray diffraction experiments.

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

PubMed

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

2014-05-01

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

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

PubMed Central

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

2014-01-01

Coherent X-ray diffraction imaging is a promising technique for visualizing the structures of non-crystalline particles with dimensions of micrometers to sub-micrometers. Recently, X-ray free-electron laser sources have enabled efficient experiments in the ‘diffraction before destruction’ scheme. Diffraction experiments have been conducted at SPring-8 Angstrom Compact free-electron LAser (SACLA) using the custom-made diffraction apparatus KOTOBUKI-1 and two multiport CCD detectors. In the experiments, ten thousands of single-shot diffraction patterns can be collected within several hours. Then, diffraction patterns with significant levels of intensity suitable for structural analysis must be found, direct-beam positions in diffraction patterns determined, diffraction patterns from the two CCD detectors merged, and phase-retrieval calculations for structural analyses performed. A software suite named SITENNO has been developed to semi-automatically apply the four-step processing to a huge number of diffraction data. Here, details of the algorithm used in the suite are described and the performance for approximately 9000 diffraction patterns collected from cuboid-shaped copper oxide particles reported. Using the SITENNO suite, it is possible to conduct experiments with data processing immediately after the data collection, and to characterize the size distribution and internal structures of the non-crystalline particles. PMID:24763651

Characterization of Limestone as Raw Material to Hydrated Lime

NASA Astrophysics Data System (ADS)

Salem Hwidi, Rajeb; Nuraiti Tengku Izhar, Tengku; Saad, Farah Naemah Mohd

2018-03-01

In Malaysia, limestone is essentially important for the economic growth as raw materials in the industry sector. Nevertheless, a little attention was paid to the physical, chemical, mineralogical, and morphological properties of the limestone using X-ray fluorescence (X-RF), X-ray diffraction (X-RD), Fourier transform infrared spectroscopy (FTIR), and Scanning electron microscopy / energy dispersive x-ray spectroscopy (SEM-EDS) respectively. Raw materials (limestone rocks) were collected from Bukit Keteri area, Chuping, Kangar, Perlis, Malaysia. Lab crusher and lab sieved were utilized to prepare five different size of ground limestone at (75 µm, 150 µm, 225 µm, 300, and 425 µm) respectively. It is found that the main chemical composition of bulk limestone was Calcium oxide (CaO) at 97.58 wt.% and trace amount of MnO, Al2O3, and Fe2O3 at 0.02%, 0.35%, and 0.396% respectively. XRD diffractograms showed characteristic peaks of calcite and quartz. Furthermore, main FTIR absorption bands at 1,419, 874.08 and 712.20 cm-1 indicated the presence of calcite. The micrographs showed clearly the difference of samples particle size. Furthermore, EDS peaks of Ca, O, and C elements confirmed the presence of CaCO3 in the samples.

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1992-02-01

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

An instrument for in situ coherent x-ray studies of metal-organic vapor phase epitaxy of III-nitrides.

PubMed

Ju, Guangxu; Highland, Matthew J; Yanguas-Gil, Angel; Thompson, Carol; Eastman, Jeffrey A; Zhou, Hua; Brennan, Sean M; Stephenson, G Brian; Fuoss, Paul H

2017-03-01

We describe an instrument that exploits the ongoing revolution in synchrotron sources, optics, and detectors to enable in situ studies of metal-organic vapor phase epitaxy (MOVPE) growth of III-nitride materials using coherent x-ray methods. The system includes high-resolution positioning of the sample and detector including full rotations, an x-ray transparent chamber wall for incident and diffracted beam access over a wide angular range, and minimal thermal sample motion, giving the sub-micron positional stability and reproducibility needed for coherent x-ray studies. The instrument enables surface x-ray photon correlation spectroscopy, microbeam diffraction, and coherent diffraction imaging of atomic-scale surface and film structure and dynamics during growth, to provide fundamental understanding of MOVPE processes.

An instrument for in situ coherent x-ray studies of metal-organic vapor phase epitaxy of III-nitrides

NASA Astrophysics Data System (ADS)

Ju, Guangxu; Highland, Matthew J.; Yanguas-Gil, Angel; Thompson, Carol; Eastman, Jeffrey A.; Zhou, Hua; Brennan, Sean M.; Stephenson, G. Brian; Fuoss, Paul H.

2017-03-01

We describe an instrument that exploits the ongoing revolution in synchrotron sources, optics, and detectors to enable in situ studies of metal-organic vapor phase epitaxy (MOVPE) growth of III-nitride materials using coherent x-ray methods. The system includes high-resolution positioning of the sample and detector including full rotations, an x-ray transparent chamber wall for incident and diffracted beam access over a wide angular range, and minimal thermal sample motion, giving the sub-micron positional stability and reproducibility needed for coherent x-ray studies. The instrument enables surface x-ray photon correlation spectroscopy, microbeam diffraction, and coherent diffraction imaging of atomic-scale surface and film structure and dynamics during growth, to provide fundamental understanding of MOVPE processes.

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

NASA Astrophysics Data System (ADS)

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

2005-08-01

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

Conceptual Design for Time-Resolved X-ray Diffraction in a Single Laser-Driven Compression Experiment

NASA Astrophysics Data System (ADS)

Benedetti, Laura Robin; Eggert, J. H.; Kilkenny, J. D.; Bradley, D. K.; Bell, P. M.; Palmer, N. E.; Rygg, J. R.; Boehly, T. R.; Collins, G. W.; Sorce, C.

2017-06-01

Since X-ray diffraction is the most definitive method for identifying crystalline phases of a material, it is an important technique for probing high-energy-density materials during laser-driven compression experiments. We are developing a design for collecting several x-ray diffraction datasets during a single laser-driven experiment, with a goal of achieving temporal resolution better than 1ns. The design combines x-ray streak cameras, for a continuous temporal record of diffraction, with fast x-ray imagers, to collect several diffraction patterns with sufficient solid angle range and resolution to identify crystalline texture. Preliminary experiments will be conducted at the Omega laser and then implemented at the National Ignition Facility. We will describe the status of the conceptual design, highlighting tradeoffs in the design process. We will also discuss the technical issues that must be addressed in order to develop a successful experimental platform. These include: Facility-specific geometric constraints such as unconverted laser light and target alignment; EMP issues when electronic diagnostics are close to the target; X-ray source requirements; and detector capabilities. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344, LLNL-ABS-725146.

IDATEN and G-SITENNO: GUI-assisted software for coherent X-ray diffraction imaging experiments and data analyses at SACLA.

PubMed

Sekiguchi, Yuki; Yamamoto, Masaki; Oroguchi, Tomotaka; Takayama, Yuki; Suzuki, Shigeyuki; Nakasako, Masayoshi

2014-11-01

Using our custom-made diffraction apparatus KOTOBUKI-1 and two multiport CCD detectors, cryogenic coherent X-ray diffraction imaging experiments have been undertaken at the SPring-8 Angstrom Compact free electron LAser (SACLA) facility. To efficiently perform experiments and data processing, two software suites with user-friendly graphical user interfaces have been developed. The first is a program suite named IDATEN, which was developed to easily conduct four procedures during experiments: aligning KOTOBUKI-1, loading a flash-cooled sample into the cryogenic goniometer stage inside the vacuum chamber of KOTOBUKI-1, adjusting the sample position with respect to the X-ray beam using a pair of telescopes, and collecting diffraction data by raster scanning the sample with X-ray pulses. Named G-SITENNO, the other suite is an automated version of the original SITENNO suite, which was designed for processing diffraction data. These user-friendly software suites are now indispensable for collecting a large number of diffraction patterns and for processing the diffraction patterns immediately after collecting data within a limited beam time.

Dynamical diffraction imaging (topography) with X-ray synchrotron radiation

NASA Technical Reports Server (NTRS)

Kuriyama, M.; Steiner, B. W.; Dobbyn, R. C.

1989-01-01

By contrast to electron microscopy, which yields information on the location of features in small regions of materials, X-ray diffraction imaging can portray minute deviations from perfect crystalline order over larger areas. Synchrotron radiation-based X-ray optics technology uses a highly parallel incident beam to eliminate ambiguities in the interpretation of image details; scattering phenomena previously unobserved are now readily detected. Synchrotron diffraction imaging renders high-resolution, real-time, in situ observations of materials under pertinent environmental conditions possible.

Development of Thin Films as Potential Structural Cathodes to Enable Multifunctional Energy-Storage Structural Composite Batteries for the U.S. Army’s Future Force

DTIC Science & Technology

2011-09-01

glancing angle X - ray diffraction (GAXRD), atomic force microscopy (AFM), scanning electron microscopy (SEM), and electrochemical...Emission SEM FWHM full width at half maximum GAXRD glancing angle X - ray diffraction H3COCH2CH2OH 2-methoxyethanol LiMn2O4 lithium manganese oxide...were characterized by scanning electron microscopy (SEM), X - ray diffraction (XRD), and atomic force microscopy (AFM). In addition,

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jones, Michael W. M.; Phillips, Nicholas W.; van Riessen, Grant A.

2016-08-11

Owing to its extreme sensitivity, quantitative mapping of elemental distributionsviaX-ray fluorescence microscopy (XFM) has become a key microanalytical technique. The recent realisation of scanning X-ray diffraction microscopy (SXDM) meanwhile provides an avenue for quantitative super-resolved ultra-structural visualization. The similarity of their experimental geometries indicates excellent prospects for simultaneous acquisition. Here, in both step- and fly-scanning modes, robust, simultaneous XFM-SXDM is demonstrated.

An Excel Spreadsheet for a One-Dimensional Fourier Map in X-ray Crystallography

ERIC Educational Resources Information Center

Clegg, William

2004-01-01

The teaching of crystal structure determination with single-crystal X-ray diffraction at undergraduate level faces numerous challenges. Single-crystal X-ray diffraction is used in a vast range of chemical research projects and forms the basis for a high proportion of structural results that are presented to high-school, undergraduate, and graduate…

Laser-induced Multi-energy Processing in Diamond Growth

DTIC Science & Technology

2012-05-01

microscopy (SEM) and energy dispersive X - ray (EDX) measurements, Drs. Yi Liu and Shah Valloppilly from Nebraska Center for Materials and Nanoscience...NCMN) at UNL for help on X - Ray diffraction (XRD) measurements, and Professor Steve W. Martin and Dr. Young Sik Kim from the Department of Material...spectroscopy and X - ray diffraction ................... 62 4.4 Conclusions

Highly crystalline MoS{sub 2} thin films grown by pulsed laser deposition

DOE Office of Scientific and Technical Information (OSTI.GOV)

Serrao, Claudy R.; You, Long; Gadgil, Sushant

2015-02-02

Highly crystalline thin films of MoS{sub 2} were prepared over large area by pulsed laser deposition down to a single monolayer on Al{sub 2}O{sub 3} (0001), GaN (0001), and SiC-6H (0001) substrates. X-ray diffraction and selected area electron diffraction studies show that the films are quasi-epitaxial with good out-of-plane texture. In addition, the thin films were observed to be highly crystalline with rocking curve full width half maxima of 0.01°, smooth with a RMS roughness of 0.27 nm, and uniform in thickness based on Raman spectroscopy. From transport measurements, the as-grown films were found to be p-type.

Two-dimensional time-resolved X-ray diffraction study of liquid/solid fraction and solid particle size in Fe-C binary system with an electrostatic levitator furnace

NASA Astrophysics Data System (ADS)

Yonemura, M.; Okada, J.; Watanabe, Y.; Ishikawa, T.; Nanao, S.; Shobu, T.; Toyokawa, H.

2013-03-01

Liquid state provides functions such as matter transport or a reaction field and plays an important role in manufacturing processes such as refining, forging or welding. However, experimental procedures are significantly difficult for an observation of solidification process of iron and iron-based alloys in order to identify rapid transformations subjected to fast temperature evolution. Therefore, in order to study the solidification in iron and iron-based alloys, we considered a combination of high energy X-ray diffraction measurements and an electrostatic levitation method (ESL). In order to analyze the liquid/solid fraction, the solidification of melted spherical specimens was measured at a time resolution of 0.1 seconds during rapid cooling using the two-dimensional time-resolved X-ray diffraction. Furthermore, the observation of particle sizes and phase identification was performed on a trial basis using X-ray small angle scattering with X-ray diffraction.

Imaging single cells in a beam of live cyanobacteria with an X-ray laser.

PubMed

van der Schot, Gijs; Svenda, Martin; Maia, Filipe R N C; Hantke, Max; DePonte, Daniel P; Seibert, M Marvin; Aquila, Andrew; Schulz, Joachim; Kirian, Richard; Liang, Mengning; Stellato, Francesco; Iwan, Bianca; Andreasson, Jakob; Timneanu, Nicusor; Westphal, Daniel; Almeida, F Nunes; Odic, Dusko; Hasse, Dirk; Carlsson, Gunilla H; Larsson, Daniel S D; Barty, Anton; Martin, Andrew V; Schorb, Sebastian; Bostedt, Christoph; Bozek, John D; Rolles, Daniel; Rudenko, Artem; Epp, Sascha; Foucar, Lutz; Rudek, Benedikt; Hartmann, Robert; Kimmel, Nils; Holl, Peter; Englert, Lars; Duane Loh, Ne-Te; Chapman, Henry N; Andersson, Inger; Hajdu, Janos; Ekeberg, Tomas

2015-02-11

There exists a conspicuous gap of knowledge about the organization of life at mesoscopic levels. Ultra-fast coherent diffractive imaging with X-ray free-electron lasers can probe structures at the relevant length scales and may reach sub-nanometer resolution on micron-sized living cells. Here we show that we can introduce a beam of aerosolised cyanobacteria into the focus of the Linac Coherent Light Source and record diffraction patterns from individual living cells at very low noise levels and at high hit ratios. We obtain two-dimensional projection images directly from the diffraction patterns, and present the results as synthetic X-ray Nomarski images calculated from the complex-valued reconstructions. We further demonstrate that it is possible to record diffraction data to nanometer resolution on live cells with X-ray lasers. Extension to sub-nanometer resolution is within reach, although improvements in pulse parameters and X-ray area detectors will be necessary to unlock this potential.

Preparation of Al-Si Master Alloy by Electrochemical Reduction of Volcanic Rock in Cryolite Molten Salt

NASA Astrophysics Data System (ADS)

Liu, Aimin; Shi, Zhongning; Xu, Junli; Hu, Xianwei; Gao, Bingliang; Wang, Zhaowen

2016-06-01

Volcanic rock found in the Longgang Volcano Group in Jilin Province of China has properties essentially similar to Apollo lunar soils and previously prepared lunar soil simulants, such as Johnson Space Center Lunar simulant and Minnesota Lunar simulant. In this study, an electrochemical method of preparation of Al-Si master alloy was investigated in 52.7 wt.%NaF-47.3 wt.%AlF3 melt adding 5 wt.% volcanic rock at 1233 K. The cathodic electrochemical process was studied by cyclic voltammetry, and the results showed that the cathodic reduction of Si(IV) is a two-step reversible diffusion-controlled reaction. Si(IV) is reduced to Si(II) by two electron transfers at -1.05 V versus platinum quasi-reference electrode in 52.7 wt.%NaF-47.3 wt.%AlF3 molten salt adding 5 wt.% volcanic rock, while the reduction peak at -1.18 V was the co-deposition of aluminum and silicon. In addition, the cathodic product obtained by galvanostatic electrolysis for 4 h was analyzed by means of x-ray diffraction, x-ray fluorescence, scanning electron microscopy and energy dispersive spectrometry. The results showed that the phase compositions of the products are Al, Si, Al5FeSi, and Al3.21Si0.47, while the components are 90.5 wt.% aluminum, 4.4 wt.% silicon, 1.9 wt.% iron, and 0.2 wt.% titanium.

High-resolution X-ray diffraction with no sample preparation

PubMed Central

Turner, S. M. R.; Degryse, P.; Shortland, A. J.

2017-01-01

It is shown that energy-dispersive X-ray diffraction (EDXRD) implemented in a back-reflection geometry is extremely insensitive to sample morphology and positioning even in a high-resolution configuration. This technique allows high-quality X-ray diffraction analysis of samples that have not been prepared and is therefore completely non-destructive. The experimental technique was implemented on beamline B18 at the Diamond Light Source synchrotron in Oxfordshire, UK. The majority of the experiments in this study were performed with pre-characterized geological materials in order to elucidate the characteristics of this novel technique and to develop the analysis methods. Results are presented that demonstrate phase identification, the derivation of precise unit-cell parameters and extraction of microstructural information on unprepared rock samples and other sample types. A particular highlight was the identification of a specific polytype of a muscovite in an unprepared mica schist sample, avoiding the time-consuming and difficult preparation steps normally required to make this type of identification. The technique was also demonstrated in application to a small number of fossil and archaeological samples. Back-reflection EDXRD implemented in a high-resolution configuration shows great potential in the crystallographic analysis of cultural heritage artefacts for the purposes of scientific research such as provenancing, as well as contributing to the formulation of conservation strategies. Possibilities for moving the technique from the synchrotron into museums are discussed. The avoidance of the need to extract samples from high-value and rare objects is a highly significant advantage, applicable also in other potential research areas such as palaeontology, and the study of meteorites and planetary materials brought to Earth by sample-return missions. PMID:28660862

Ultrafast electron crystallography: Transient structures of molecules, surfaces, and phase transitions

PubMed Central

Ruan, Chong-Yu; Vigliotti, Franco; Lobastov, Vladimir A.; Chen, Songye; Zewail, Ahmed H.

2004-01-01

The static structure of macromolecular assemblies can be mapped out with atomic-scale resolution by using electron diffraction and microscopy of crystals. For transient nonequilibrium structures, which are critical to the understanding of dynamics and mechanisms, both spatial and temporal resolutions are required; the shortest scales of length (0.1–1 nm) and time (10–13 to 10–12 s) represent the quantum limit, the nonstatistical regime of rates. Here, we report the development of ultrafast electron crystallography for direct determination of structures with submonolayer sensitivity. In these experiments, we use crystalline silicon as a template for different adsorbates: hydrogen, chlorine, and trifluoroiodomethane. We observe the coherent restructuring of the surface layers with subangstrom displacement of atoms after the ultrafast heat impulse. This nonequilibrium dynamics, which is monitored in steps of 2 ps (total change ≤10 ps), contrasts that of the nanometer substrate. The effect of adsorbates and the phase transition at higher fluences were also studied through the evolution of streaks of interferences, Bragg spots (and their rocking curves), and rings in the diffraction patterns. We compare these results with kinematical theory and those of x-ray diffraction developed to study bulk behaviors. The sensitivity achieved here, with the 6 orders of magnitude larger cross section than x-ray diffraction, and with the capabilities of combined spatial (≈0.01 Å) and temporal (300–600 fs) resolutions, promise diverse applications for this ultrafast electron crystallography tabletop methodology. PMID:14745037

Synchrotron Bragg diffraction imaging characterization of synthetic diamond crystals for optical and electronic power device applications1 1

PubMed Central

Tran Thi, Thu Nhi; Morse, J.; Caliste, D.; Fernandez, B.; Eon, D.; Härtwig, J.; Mer-Calfati, C.; Tranchant, N.; Arnault, J. C.; Lafford, T. A.; Baruchel, J.

2017-01-01

Bragg diffraction imaging enables the quality of synthetic single-crystal diamond substrates and their overgrown, mostly doped, diamond layers to be characterized. This is very important for improving diamond-based devices produced for X-ray optics and power electronics applications. The usual first step for this characterization is white-beam X-ray diffraction topography, which is a simple and fast method to identify the extended defects (dislocations, growth sectors, boundaries, stacking faults, overall curvature etc.) within the crystal. This allows easy and quick comparison of the crystal quality of diamond plates available from various commercial suppliers. When needed, rocking curve imaging (RCI) is also employed, which is the quantitative counterpart of monochromatic Bragg diffraction imaging. RCI enables the local determination of both the effective misorientation, which results from lattice parameter variation and the local lattice tilt, and the local Bragg position. Maps derived from these parameters are used to measure the magnitude of the distortions associated with polishing damage and the depth of this damage within the volume of the crystal. For overgrown layers, these maps also reveal the distortion induced by the incorporation of impurities such as boron, or the lattice parameter variations associated with the presence of growth-incorporated nitrogen. These techniques are described, and their capabilities for studying the quality of diamond substrates and overgrown layers, and the surface damage caused by mechanical polishing, are illustrated by examples. PMID:28381981

Major Element Analysis of the Target Rocks at Meteor Crater, Arizona

NASA Technical Reports Server (NTRS)

See, Thomas H.; Hoerz, Friedrich; Mittlefehldt, David W.; Varley, Laura; Mertzman, Stan; Roddy, David

2002-01-01

We collected approximately 400 rock chips in continuous vertical profile at Meteor Crater, Arizona, representing, from bottom to top, the Coconino, Toroweap, Kaibab, and Moenkopi Formations to support ongoing compositional analyses of the impact melts and their stratigraphic source depth(s) and other studies at Meteor Crater that depend on the composition of the target rocks. These rock chips were subsequently pooled into 23 samples for compositional analysis by XRF (x ray fluorescence) methods, each sample reflecting a specific stratigraphic "subsection" approximately 5-10 in thick. We determined the modal abundance of quartz, dolomite, and calcite for the entire Kaibab Formation at vertical resolutions of 1-2 meters. The Coconino Formation composes the lower half of the crater cavity. It is an exceptionally pure sandstone. The Toroweap is only two inches thick and compositionally similar to Coconino, therefore, it is not a good compositional marker horizon. The Kaibab Formation is approximately 80 in thick. XRD (x ray diffraction) studies show that the Kaibab Formation is dominated by dolomite and quartz, albeit in highly variable proportions; calcite is a minor phase at best. The Kaibab at Meteor Crater is therefore a sandy dolomite rather than a limestone, consistent with pronounced facies changes in the Permian of SE Arizona over short vertical and horizontal distances. The Moenkopi forms the 12 in thick cap rock and has the highest Al2O3 and FeO concentrations of all target rocks. With several examples, we illustrate how this systematic compositional and modal characterization of the target ideologies may contribute to an understanding of Meteor Crater, such as the depth of its melt zone, and to impact cratering in general, such as the liberation of CO2 from shocked carbonates.

Luminescent properties under X-ray excitation of Ba(1-x)PbxWO4 disordered solid solution

NASA Astrophysics Data System (ADS)

Bakiz, B.; Hallaoui, A.; Taoufyq, A.; Benlhachemi, A.; Guinneton, F.; Villain, S.; Ezahri, M.; Valmalette, J.-C.; Arab, M.; Gavarri, J.-R.

2018-02-01

A series of polycrystalline barium-lead tungstate Ba1-xPbxWO4 with 0 ≤ x ≤ 1 was synthesized using a classical solid-state method with thermal treatment at 1000 °C. These materials were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier Transform Raman (FT-Raman) spectroscopy. X-ray diffraction profile analyses were performed using Rietveld method. These materials crystallized in the scheelite tetragonal structure and behaved as quasi ideal solid solution. Raman spectroscopy confirmed the formation of the solid solution. Structural distortions were evidenced in X-ray diffraction profiles and in vibration Raman spectra. The scanning electron microscopy experiments showed large and rounded irregular grains. Luminescence experiments were performed under X-ray excitation. The luminescence emission profiles have been interpreted in terms of four Gaussian components, with a major contribution of blue emission. The integrated intensity of luminescence reached a maximum value in the composition range x = 0.3-0.6, in relation with distortions of crystal lattice.

X-ray Diffraction, Big and Small

NASA Image and Video Library

2012-10-30

A conventional X-ray diffraction instrument left is the size of a large refrigerator, in contrast to the compact size of the Chemistry and Mineralogy CheMin instrument on NASA Curiosity rover top right.

Coherent diffraction of single Rice Dwarf virus particles using hard X-rays at the Linac Coherent Light Source

PubMed Central

Munke, Anna; Andreasson, Jakob; Aquila, Andrew; Awel, Salah; Ayyer, Kartik; Barty, Anton; Bean, Richard J.; Berntsen, Peter; Bielecki, Johan; Boutet, Sébastien; Bucher, Maximilian; Chapman, Henry N.; Daurer, Benedikt J.; DeMirci, Hasan; Elser, Veit; Fromme, Petra; Hajdu, Janos; Hantke, Max F.; Higashiura, Akifumi; Hogue, Brenda G.; Hosseinizadeh, Ahmad; Kim, Yoonhee; Kirian, Richard A.; Reddy, Hemanth K.N.; Lan, Ti-Yen; Larsson, Daniel S.D.; Liu, Haiguang; Loh, N. Duane; Maia, Filipe R.N.C.; Mancuso, Adrian P.; Mühlig, Kerstin; Nakagawa, Atsushi; Nam, Daewoong; Nelson, Garrett; Nettelblad, Carl; Okamoto, Kenta; Ourmazd, Abbas; Rose, Max; van der Schot, Gijs; Schwander, Peter; Seibert, M. Marvin; Sellberg, Jonas A.; Sierra, Raymond G.; Song, Changyong; Svenda, Martin; Timneanu, Nicusor; Vartanyants, Ivan A.; Westphal, Daniel; Wiedorn, Max O.; Williams, Garth J.; Xavier, Paulraj Lourdu; Yoon, Chun Hong; Zook, James

2016-01-01

Single particle diffractive imaging data from Rice Dwarf Virus (RDV) were recorded using the Coherent X-ray Imaging (CXI) instrument at the Linac Coherent Light Source (LCLS). RDV was chosen as it is a well-characterized model system, useful for proof-of-principle experiments, system optimization and algorithm development. RDV, an icosahedral virus of about 70 nm in diameter, was aerosolized and injected into the approximately 0.1 μm diameter focused hard X-ray beam at the CXI instrument of LCLS. Diffraction patterns from RDV with signal to 5.9 Ångström were recorded. The diffraction data are available through the Coherent X-ray Imaging Data Bank (CXIDB) as a resource for algorithm development, the contents of which are described here. PMID:27478984

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

DOE PAGES

Huang, Xiaojing; Miao, Huijie; Steinbrener, Jan; ...

2009-01-01

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

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

DOE PAGES

Cha, Wonsuk; Liu, Wenjun; Harder, Ross; ...

2016-07-26

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

Coherent diffraction of single Rice Dwarf virus particles using hard X-rays at the Linac Coherent Light Source

DOE PAGES

Munke, Anna; Andreasson, Jakob; Aquila, Andrew; ...

2016-08-01

Single particle diffractive imaging data from Rice Dwarf Virus (RDV) were recorded using the Coherent X-ray Imaging (CXI) instrument at the Linac Coherent Light Source (LCLS). RDV was chosen as it is a well-characterized model system, useful for proof-of-principle experiments, system optimization and algorithm development. RDV, an icosahedral virus of about 70 nm in diameter, was aerosolized and injected into the approximately 0.1 μm diameter focused hard X-ray beam at the CXI instrument of LCLS. Diffraction patterns from RDV with signal to 5.9 Ångström were recorded. Here, the diffraction data are available through the Coherent X-ray Imaging Data Bank (CXIDB)more » as a resource for algorithm development, the contents of which are described here.« less

Influence of neutron irradiation on the microstructure of nuclear graphite: An X-ray diffraction study

NASA Astrophysics Data System (ADS)

Zhou, Z.; Bouwman, W. G.; Schut, H.; van Staveren, T. O.; Heijna, M. C. R.; Pappas, C.

2017-04-01

Neutron irradiation effects on the microstructure of nuclear graphite have been investigated by X-ray diffraction on virgin and low doses (∼ 1.3 and ∼ 2.2 dpa), high temperature (750° C) irradiated samples. The diffraction patterns were interpreted using a model, which takes into account the turbostratic disorder. Besides the lattice constants, the model introduces two distinct coherent lengths in the c-axis and the basal plane, that characterise the volumes from which X-rays are scattered coherently. The methodology used in this work allows to quantify the effect of irradiation damage on the microstructure of nuclear graphite seen by X-ray diffraction. The results show that the changes of the deduced structural parameters are in agreement with previous observations from electron microscopy, but not directly related to macroscopic changes.

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

PubMed

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

2016-09-01

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

Time-spliced X-ray diffraction imaging of magnetism dynamics in a NdNiO3 thin film

NASA Astrophysics Data System (ADS)

Beyerlein, Kenneth R.

2018-03-01

Diffraction imaging of nonequilibrium dynamics at atomic resolution is becoming possible with X-ray free-electron lasers. However, there are unresolved problems with applying this method to objects that are confined in only one dimension. Here I show that reliable one-dimensional coherent diffraction imaging is possible by splicing together images recovered from different time delays in an optical pump X-ray probe experiment. The time and space evolution of antiferromagnetic order in a vibrationally excited complex oxide heterostructure is recovered from time-resolved measurements of a resonant soft X-ray diffraction peak. Midinfrared excitation of the substrate is shown to lead to a demagnetization front that propagates at a velocity exceeding the speed of sound, a critical observation for the understanding of driven phase transitions in complex condensed matter.

Coherent diffraction of single Rice Dwarf virus particles using hard X-rays at the Linac Coherent Light Source.

PubMed

Munke, Anna; Andreasson, Jakob; Aquila, Andrew; Awel, Salah; Ayyer, Kartik; Barty, Anton; Bean, Richard J; Berntsen, Peter; Bielecki, Johan; Boutet, Sébastien; Bucher, Maximilian; Chapman, Henry N; Daurer, Benedikt J; DeMirci, Hasan; Elser, Veit; Fromme, Petra; Hajdu, Janos; Hantke, Max F; Higashiura, Akifumi; Hogue, Brenda G; Hosseinizadeh, Ahmad; Kim, Yoonhee; Kirian, Richard A; Reddy, Hemanth K N; Lan, Ti-Yen; Larsson, Daniel S D; Liu, Haiguang; Loh, N Duane; Maia, Filipe R N C; Mancuso, Adrian P; Mühlig, Kerstin; Nakagawa, Atsushi; Nam, Daewoong; Nelson, Garrett; Nettelblad, Carl; Okamoto, Kenta; Ourmazd, Abbas; Rose, Max; van der Schot, Gijs; Schwander, Peter; Seibert, M Marvin; Sellberg, Jonas A; Sierra, Raymond G; Song, Changyong; Svenda, Martin; Timneanu, Nicusor; Vartanyants, Ivan A; Westphal, Daniel; Wiedorn, Max O; Williams, Garth J; Xavier, Paulraj Lourdu; Yoon, Chun Hong; Zook, James

2016-08-01

Single particle diffractive imaging data from Rice Dwarf Virus (RDV) were recorded using the Coherent X-ray Imaging (CXI) instrument at the Linac Coherent Light Source (LCLS). RDV was chosen as it is a well-characterized model system, useful for proof-of-principle experiments, system optimization and algorithm development. RDV, an icosahedral virus of about 70 nm in diameter, was aerosolized and injected into the approximately 0.1 μm diameter focused hard X-ray beam at the CXI instrument of LCLS. Diffraction patterns from RDV with signal to 5.9 Ångström were recorded. The diffraction data are available through the Coherent X-ray Imaging Data Bank (CXIDB) as a resource for algorithm development, the contents of which are described here.

Time-spliced X-ray diffraction imaging of magnetism dynamics in a NdNiO3 thin film.

PubMed

Beyerlein, Kenneth R

2018-02-27

Diffraction imaging of nonequilibrium dynamics at atomic resolution is becoming possible with X-ray free-electron lasers. However, there are unresolved problems with applying this method to objects that are confined in only one dimension. Here I show that reliable one-dimensional coherent diffraction imaging is possible by splicing together images recovered from different time delays in an optical pump X-ray probe experiment. The time and space evolution of antiferromagnetic order in a vibrationally excited complex oxide heterostructure is recovered from time-resolved measurements of a resonant soft X-ray diffraction peak. Midinfrared excitation of the substrate is shown to lead to a demagnetization front that propagates at a velocity exceeding the speed of sound, a critical observation for the understanding of driven phase transitions in complex condensed matter.

Preliminary small-angle X-ray scattering and X-ray diffraction studies of the BTB domain of lola protein from Drosophila melanogaster

NASA Astrophysics Data System (ADS)

Boyko, K. M.; Nikolaeva, A. Yu.; Kachalova, G. S.; Bonchuk, A. N.; Dorovatovskii, P. V.; Popov, V. O.

2017-11-01

The Drosophila genome has several dozens of transcription factors (TTK group) containing BTB domains assembled into octamers. The LOLA protein belongs to this family. The purification, crystallization, and preliminary X-ray diffraction and small-angle X-ray scattering (SAXS) studies of the BTB domain of this protein are reported. The crystallization conditions were found by the vapor-diffusion technique. A very low diffraction resolution (8.7 Å resolution) of the crystals was insufficient for the determination of the threedimensional structure of the BTB domain. The SAXS study demonstrated that the BTB domain of the LOLA protein exists as an octamer in solution.

Cryogenic x-ray diffraction microscopy utilizing high-pressure cryopreservation

NASA Astrophysics Data System (ADS)

Lima, Enju; Chushkin, Yuriy; van der Linden, Peter; Kim, Chae Un; Zontone, Federico; Carpentier, Philippe; Gruner, Sol M.; Pernot, Petra

2014-10-01

We present cryo x-ray diffraction microscopy of high-pressure-cryofixed bacteria and report high-convergence imaging with multiple image reconstructions. Hydrated D. radiodurans cells were cryofixed at 200 MPa pressure into ˜10-μm-thick water layers and their unstained, hydrated cellular environments were imaged by phasing diffraction patterns, reaching sub-30-nm resolutions with hard x-rays. Comparisons were made with conventional ambient-pressure-cryofixed samples, with respect to both coherent small-angle x-ray scattering and the image reconstruction. The results show a correlation between the level of background ice signal and phasing convergence, suggesting that phasing difficulties with frozen-hydrated specimens may be caused by high-background ice scattering.

Synchrotron X-ray powder diffraction data of LASSBio-1515: A new N-acylhydrazone derivative compound

NASA Astrophysics Data System (ADS)

Costa, F. N.; Braz, D.; Ferreira, F. F.; da Silva, T. F.; Barreiro, E. J.; Lima, L. M.; Colaço, M. V.; Kuplich, L.; Barroso, R. C.

2014-02-01

In this work, synchrotron X-ray powder diffraction data allowed for a successful indexing of LASSBio-1515 compound, candidate to analgesic and anti-inflammatory activity. X-ray powder diffraction data collected in transmission and high-throughput geometries were used to analyze this compound. The X-ray wavelength of the synchrotron radiation used in this study was determined to be λ=1.55054 Å. LASSBio-1515 was found to be monoclinic with space group P21/c and unit cell parameters a=11.26255(16) Å, b=12.59785(16) Å, c=8.8540(1) Å, β=90.5972(7)° and V=1256.17(3) Å3.

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

PubMed

Tokuhisa, Atsushi; Arai, Junya; Joti, Yasumasa; Ohno, Yoshiyuki; Kameyama, Toyohisa; Yamamoto, Keiji; Hatanaka, Masayuki; Gerofi, Balazs; Shimada, Akio; Kurokawa, Motoyoshi; Shoji, Fumiyoshi; Okada, Kensuke; Sugimoto, Takashi; Yamaga, Mitsuhiro; Tanaka, Ryotaro; Yokokawa, Mitsuo; Hori, Atsushi; Ishikawa, Yutaka; Hatsui, Takaki; Go, Nobuhiro

2013-11-01

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

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

PubMed Central

Tokuhisa, Atsushi; Arai, Junya; Joti, Yasumasa; Ohno, Yoshiyuki; Kameyama, Toyohisa; Yamamoto, Keiji; Hatanaka, Masayuki; Gerofi, Balazs; Shimada, Akio; Kurokawa, Motoyoshi; Shoji, Fumiyoshi; Okada, Kensuke; Sugimoto, Takashi; Yamaga, Mitsuhiro; Tanaka, Ryotaro; Yokokawa, Mitsuo; Hori, Atsushi; Ishikawa, Yutaka; Hatsui, Takaki; Go, Nobuhiro

2013-01-01

Single-particle coherent X-ray diffraction imaging using an X-ray free-electron laser has the potential to reveal the three-dimensional structure of a biological supra-molecule at sub-nanometer resolution. In order to realise this method, it is necessary to analyze as many as 1 × 106 noisy X-ray diffraction patterns, each for an unknown random target orientation. To cope with the severe quantum noise, patterns need to be classified according to their similarities and average similar patterns to improve the signal-to-noise ratio. A high-speed scalable scheme has been developed to carry out classification on the K computer, a 10PFLOPS supercomputer at RIKEN Advanced Institute for Computational Science. It is designed to work on the real-time basis with the experimental diffraction pattern collection at the X-ray free-electron laser facility SACLA so that the result of classification can be feedback for optimizing experimental parameters during the experiment. The present status of our effort developing the system and also a result of application to a set of simulated diffraction patterns is reported. About 1 × 106 diffraction patterns were successfully classificatied by running 255 separate 1 h jobs in 385-node mode. PMID:24121336

Elucidating the Wavelength Dependence of Phonon Scattering in Nanoparticle-Matrix Composites using Phonon Spectroscopy

DTIC Science & Technology

2016-07-11

composites with x - ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), Rutherford backscattering spectroscopy...RBS), particle-induced x - ray emission (PIXE), and energy dispersive x - ray spectroscopy (EDX). This work complements earlier works on CdSe...sample shows only In2Se3 and CdIn2Se4 XRD peaks (Figure 1.4e), it is stoichiometrically   Figure 1.4. X - ray diffraction patterns of (a) γ-In2Se3

Applications of High Throughput (Combinatorial) Methodologies to Electronic, Magnetic, Optical, and Energy-Related Materials

DTIC Science & Technology

2013-06-17

of the films without having to fabricate capacitors. In addition, the use of X - ray diffraction (XRD) analysis enabled Chikyow et al.40 to identify an...effects of Al doping and annealing on the thermal stabil- ity of the Y2O3/Si gate stack were studied by X - ray photoemission spectroscopy (XPS) and X - ray ...the major diffraction features in the phase distribution. For a given structural phase, the X - ray peak intensity allows one to track the compositional

Aplanatic and quasi-aplanatic diffraction gratings

DOEpatents

Hettrick, M.C.

1987-09-14

A reflection diffraction grating having a series of transverse minute grooves of progressively varying spacing along a concave surface enables use of such gratings for x-ray or longer wavelength imaging of objects. The variable groove spacing establishes aplanatism or substantially uniform magnetification across the optical aperture. The grating may be sued, for example, in x-ray microscopes or telescopes of the imaging type and in x-ray microprobed. Increased spatial resolution and field of view may be realized in x-ray imaging. 5 figs.

An instrument for in situ coherent x-ray studies of metal-organic vapor phase epitaxy of III-nitrides

DOE PAGES

Ju, Guangxu; Highland, Matthew J.; Yanguas-Gil, Angel; ...

2017-03-21

Here, we describe an instrument that exploits the ongoing revolution in synchrotron sources, optics, and detectors to enable in situ studies of metal-organic vapor phase epitaxy (MOVPE) growth of III-nitride materials using coherent x-ray methods. The system includes high-resolution positioning of the sample and detector including full rotations, an x-ray transparent chamber wall for incident and diffracted beam access over a wide angular range, and minimal thermal sample motion, giving the sub-micron positional stability and reproducibility needed for coherent x-ray studies. The instrument enables surface x-ray photon correlation spectroscopy, microbeam diffraction, and coherent diffraction imaging of atomic-scale surface and filmmore » structure and dynamics during growth, to provide fundamental understanding of MOVPE processes.« less

Towards shot-noise limited diffraction experiments with table-top femtosecond hard x-ray sources.

PubMed

Holtz, Marcel; Hauf, Christoph; Weisshaupt, Jannick; Salvador, Antonio-Andres Hernandez; Woerner, Michael; Elsaesser, Thomas

2017-09-01

Table-top laser-driven hard x-ray sources with kilohertz repetition rates are an attractive alternative to large-scale accelerator-based systems and have found widespread applications in x-ray studies of ultrafast structural dynamics. Hard x-ray pulses of 100 fs duration have been generated at the Cu K α wavelength with a photon flux of up to 10 9 photons per pulse into the full solid angle, perfectly synchronized to the sub-100-fs optical pulses from the driving laser system. Based on spontaneous x-ray emission, such sources display a particular noise behavior which impacts the sensitivity of x-ray diffraction experiments. We present a detailed analysis of the photon statistics and temporal fluctuations of the x-ray flux, together with experimental strategies to optimize the sensitivity of optical pump/x-ray probe experiments. We demonstrate measurements close to the shot-noise limit of the x-ray source.

Towards shot-noise limited diffraction experiments with table-top femtosecond hard x-ray sources

PubMed Central

Holtz, Marcel; Hauf, Christoph; Weisshaupt, Jannick; Salvador, Antonio-Andres Hernandez; Woerner, Michael; Elsaesser, Thomas

2017-01-01

Table-top laser-driven hard x-ray sources with kilohertz repetition rates are an attractive alternative to large-scale accelerator-based systems and have found widespread applications in x-ray studies of ultrafast structural dynamics. Hard x-ray pulses of 100 fs duration have been generated at the Cu Kα wavelength with a photon flux of up to 109 photons per pulse into the full solid angle, perfectly synchronized to the sub-100-fs optical pulses from the driving laser system. Based on spontaneous x-ray emission, such sources display a particular noise behavior which impacts the sensitivity of x-ray diffraction experiments. We present a detailed analysis of the photon statistics and temporal fluctuations of the x-ray flux, together with experimental strategies to optimize the sensitivity of optical pump/x-ray probe experiments. We demonstrate measurements close to the shot-noise limit of the x-ray source. PMID:28795079

The black rock series supported SCR catalyst for NO x removal.

PubMed

Xie, Bin; Luo, Hang; Tang, Qing; Du, Jun; Liu, Zuohua; Tao, Changyuan

2017-09-01

Black rock series (BRS) is of great potential for their plenty of valued oxides which include vanadium, iron, alumina and silica oxides, etc. BRS was used for directly preparing of selective catalytic reduction (SCR) catalyst by modifying its surface texture with SiO 2 -TiO 2 sols and regulating its catalytic active constituents with V 2 O 5 and MoO 3 . Consequently, 90% NO removal ratio was obtained within 300-400 °C over the BRS-based catalyst. The structure and properties of the BRS-based catalyst were characterized by the techniques of N 2 adsorption-desorption, X-ray diffraction (XRD), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), H 2 -temperature programmed reduction (H 2 -TPR), and NH 3 -temperature programmed desorption (NH 3 -TPD). The results revealed that the BRS-based catalyst possesses favorable properties for NO x removal, including highly dispersed active components, abundant surface-adsorbed oxygen O α , well redox property, and numerous Brønsted acid sites. Particularly, the BRS-based catalyst exhibited considerable anti-poisoning performance compared with commercial TiO 2 -based catalyst. The former catalyst shows a NO conversion surpassing 80% from 300 to 400 °C for potassium poisoning, and a durability of SO 2 and H 2 O exceeding 85% at temperatures from 300 to 450 °C.

X-ray shearing interferometer

DOEpatents

Koch, Jeffrey A [Livermore, CA

2003-07-08

An x-ray interferometer for analyzing high density plasmas and optically opaque materials includes a point-like x-ray source for providing a broadband x-ray source. The x-rays are directed through a target material and then are reflected by a high-quality ellipsoidally-bent imaging crystal to a diffraction grating disposed at 1.times. magnification. A spherically-bent imaging crystal is employed when the x-rays that are incident on the crystal surface are normal to that surface. The diffraction grating produces multiple beams which interfere with one another to produce an interference pattern which contains information about the target. A detector is disposed at the position of the image of the target produced by the interfering beams.

Symposium N: Materials and Devices for Thermal-to-Electric Energy Conversion

DTIC Science & Technology

2010-08-24

X - ray diffraction, transmission electron microscopy, scanning electron microscopy, and dynamic light scattering. Thermal conductivity measurements...SEM), X - ray diffraction (XRD) measurements as well as Raman spectroscopy. The results from these techniques indicate a clear modification...was examined by using scanning electron microscope (SEM; HITACHI S-4500 model) attached with an energy dispersive x - ray spectroscopy. The electrical

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

Young, Matthias J.; Bedford, Nicholas M.; Jiang, Naisheng

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

In Situ 3D Coherent X-ray Diffraction Imaging of Shock Experiments: Possible?

NASA Astrophysics Data System (ADS)

Barber, John

2011-03-01

In traditional coherent X-ray diffraction imaging (CXDI), a 2D or quasi-2D object is illuminated by a beam of coherent X-rays to produce a diffraction pattern, which is then manipulated via a process known as iterative phase retrieval to reconstruct an image of the original 2D sample. Recently, there have been dramatic advances in methods for performing fully 3D CXDI of a sample from a single diffraction pattern [Raines et al, Nature 463 214-7 (2010)], and these methods have been used to image samples tens of microns in size using soft X-rays. In this work, I explore the theoretical possibility of applying 3D CXDI techniques to the in situ imaging of the interaction between a shock front and a polycrystal, a far more stringent problem. A delicate trade-off is required between photon energy, spot size, imaging resolution, and the dimensions of the experimental setup. In this talk, I will outline the experimental and computational requirements for performing such an experiment, and I will present images and movies from simulations of one such hypothetical experiment, including both the time-resolved X-ray diffraction patterns and the time-resolved sample imagery.

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

DOEpatents

Smither, Robert K [Hinsdale, IL

2011-05-17

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

Photoluminescence studies on Cd(1-x)Zn(x)S:Mn2+ nanocrystals.

PubMed

Sethi, Ruchi; Kumar, Lokendra; Pandey, A C

2009-09-01

Highly monodispersed, undoped and doped with Mn2+, binary and ternary (CdS, ZnS, Cd(1-x)Zn(x)S) compound semiconductor nanocrystals have been synthesized by co-precipitation method using citric acid as a stabilizer. As prepared sample are characterized by X-ray diffraction, Small angle X-ray scattering, Transmission electron microscope, Optical absorption and Photoluminescence spectroscopy, for their optical and structural properties. X-ray diffraction, Small angle X-ray scattering and Transmission electron microscope results confirm the preparation of monodispersed nanocrystals. Photoluminescence studies show a significant blue shift in the wavelength with an increasing concentration of Zn in alloy nanocrystals.

Observation of sagittal X-ray diffraction by surface acoustic waves in Bragg geometry.

PubMed

Vadilonga, Simone; Zizak, Ivo; Roshchupkin, Dmitry; Evgenii, Emelin; Petsiuk, Andrei; Leitenberger, Wolfram; Erko, Alexei

2017-04-01

X-ray Bragg diffraction in sagittal geometry on a Y-cut langasite crystal (La 3 Ga 5 SiO 14 ) modulated by Λ = 3 µm Rayleigh surface acoustic waves was studied at the BESSY II synchrotron radiation facility. Owing to the crystal lattice modulation by the surface acoustic wave diffraction, satellites appear. Their intensity and angular separation depend on the amplitude and wavelength of the ultrasonic superlattice. Experimental results are compared with the corresponding theoretical model that exploits the kinematical diffraction theory. This experiment shows that the propagation of the surface acoustic waves creates a dynamical diffraction grating on the crystal surface, and this can be used for space-time modulation of an X-ray beam.

Observation of sagittal X-ray diffraction by surface acoustic waves in Bragg geometry1

PubMed Central

Vadilonga, Simone; Zizak, Ivo; Roshchupkin, Dmitry; Evgenii, Emelin; Petsiuk, Andrei; Leitenberger, Wolfram; Erko, Alexei

2017-01-01

X-ray Bragg diffraction in sagittal geometry on a Y-cut langasite crystal (La3Ga5SiO14) modulated by Λ = 3 µm Rayleigh surface acoustic waves was studied at the BESSY II synchrotron radiation facility. Owing to the crystal lattice modulation by the surface acoustic wave diffraction, satellites appear. Their intensity and angular separation depend on the amplitude and wavelength of the ultrasonic superlattice. Experimental results are compared with the corresponding theoretical model that exploits the kinematical diffraction theory. This experiment shows that the propagation of the surface acoustic waves creates a dynamical diffraction grating on the crystal surface, and this can be used for space–time modulation of an X-ray beam. PMID:28381976

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

DOEpatents

Berman, R.M.; Cohen, I.

1988-04-26

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

Dynamic x-ray imaging of laser-driven nanoplasmas

NASA Astrophysics Data System (ADS)

Fennel, Thomas

2016-05-01

A major promise of current x-ray science at free electron lasers is the realization of unprecedented imaging capabilities for resolving the structure and ultrafast dynamics of matter with nanometer spatial and femtosecond temporal resolution or even below via single-shot x-ray diffraction. Laser-driven atomic clusters and nanoparticles provide an ideal platform for developing and demonstrating the required technology to extract the ultrafast transient spatiotemporal dynamics from the diffraction images. In this talk, the perspectives and challenges of dynamic x-ray imaging will be discussed using complete self-consistent microscopic electromagnetic simulations of IR pump x-ray probe imaging for the example of clusters. The results of the microscopic particle-in-cell simulations (MicPIC) enable the simulation-assisted reconstruction of corresponding experimental data. This capability is demonstrated by converting recently measured LCLS data into a ultrahigh resolution movie of laser-induced plasma expansion. Finally, routes towards reaching attosecond time resolution in the visualization of complex dynamical processes in matter by x-ray diffraction will be discussed.

Infrastructure development for radioactive materials at the NSLS-II

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sprouster, D. J.; Weidner, R.; Ghose, S. K.

2018-02-01

The X-ray Powder Diffraction (XPD) Beamline at the National Synchrotron Light Source-II is a multipurpose instrument designed for high-resolution, high-energy X-ray scattering techniques. In this article, the capabilities, opportunities and recent developments in the characterization of radioactive materials at XPD are described. The overarching goal of this work is to provide researchers access to advanced synchrotron techniques suited to the structural characterization of materials for advanced nuclear energy systems. XPD is a new beamline providing high photon flux for X-ray Diffraction, Pair Distribution Function analysis and Small Angle X-ray Scattering. The infrastructure and software described here extend the existing capabilitiesmore » at XPD to accommodate radioactive materials. Such techniques will contribute crucial information to the characterization and quantification of advanced materials for nuclear energy applications. We describe the automated radioactive sample collection capabilities and recent X-ray Diffraction and Small Angle X-ray Scattering results from neutron irradiated reactor pressure vessel steels and oxide dispersion strengthened steels.« less

Infrastructure development for radioactive materials at the NSLS-II

DOE PAGES

Sprouster, David J.; Weidner, R.; Ghose, S. K.; ...

2017-11-04

The X-ray Powder Diffraction (XPD) Beamline at the National Synchrotron Light Source-II is a multipurpose instrument designed for high-resolution, high-energy X-ray scattering techniques. In this paper, the capabilities, opportunities and recent developments in the characterization of radioactive materials at XPD are described. The overarching goal of this work is to provide researchers access to advanced synchrotron techniques suited to the structural characterization of materials for advanced nuclear energy systems. XPD is a new beamline providing high photon flux for X-ray Diffraction, Pair Distribution Function analysis and Small Angle X-ray Scattering. The infrastructure and software described here extend the existing capabilitiesmore » at XPD to accommodate radioactive materials. Such techniques will contribute crucial information to the characterization and quantification of advanced materials for nuclear energy applications. Finally, we describe the automated radioactive sample collection capabilities and recent X-ray Diffraction and Small Angle X-ray Scattering results from neutron irradiated reactor pressure vessel steels and oxide dispersion strengthened steels.« less

Illicit drug detection using energy dispersive x-ray diffraction

NASA Astrophysics Data System (ADS)

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

2009-05-01

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

Wavefront aberrations of x-ray dynamical diffraction beams.

PubMed

Liao, Keliang; Hong, Youli; Sheng, Weifan

2014-10-01

The effects of dynamical diffraction in x-ray diffractive optics with large numerical aperture render the wavefront aberrations difficult to describe using the aberration polynomials, yet knowledge of them plays an important role in a vast variety of scientific problems ranging from optical testing to adaptive optics. Although the diffraction theory of optical aberrations was established decades ago, its application in the area of x-ray dynamical diffraction theory (DDT) is still lacking. Here, we conduct a theoretical study on the aberration properties of x-ray dynamical diffraction beams. By treating the modulus of the complex envelope as the amplitude weight function in the orthogonalization procedure, we generalize the nonrecursive matrix method for the determination of orthonormal aberration polynomials, wherein Zernike DDT and Legendre DDT polynomials are proposed. As an example, we investigate the aberration evolution inside a tilted multilayer Laue lens. The corresponding Legendre DDT polynomials are obtained numerically, which represent balanced aberrations yielding minimum variance of the classical aberrations of an anamorphic optical system. The balancing of classical aberrations and their standard deviations are discussed. We also present the Strehl ratio of the primary and secondary balanced aberrations.

X-ray characterization techniques for the assessment of surface damage in crystalline wafers: A model study in AlN

NASA Astrophysics Data System (ADS)

Bobea, M.; Tweedie, J.; Bryan, I.; Bryan, Z.; Rice, A.; Dalmau, R.; Xie, J.; Collazo, R.; Sitar, Z.

2013-03-01

A high-resolution X-ray diffraction method with enhanced surface sensitivity has been used to investigate the effects of various polishing steps on the near-surface region of single crystal substrates. The method involves the study of a highly asymmetric reflection, observable under grazing incidence conditions. Analysis of rocking curve measurements and reciprocal space maps (RSMs) revealed subtle structural differences between the polished substrates. For aluminum nitride wafers, damage induced from diamond sawing and mechanical polishing was readily identifiable by on-axis rocking curves, but this method was unable to distinguish between sample surfaces subjected to various degrees of chemical mechanical polishing (CMP). To characterize sufficiently these surfaces, (10.3) RSMs were measured to provide both qualitative and quantitative information about the near-surface region. Two features present in the RSMs were utilized to quantitatively assess the polished wafers: the magnitude of the diffuse scatter in the omega-scans and the elongation of the crystal truncation rod. The method is able to distinguish between different degrees of CMP surface preparation and provides metrics to quantify subsurface damage after this polishing step.

Revision of Hopewellian trading patterns in Midwestern North America based on mineralogical sourcing

USGS Publications Warehouse

Hughes, R.E.; Berres, T.E.; Moore, D.M.; Farnsworth, K.B.

1998-01-01

Traditional exchange models purport that all Hopewell-style platform pipes of flint clay were quarried and crafted in southern Ohio by Native Americans from a local kaolinitic flint clay, and that those found in the Havana Hopewell region of western Illinois were transported from southern Ohio along an Ohio River trade network. However, the results of this study show that berthierine-rich flint clay from northwestern Illinois was the only source for pipestone artifacts of the Havana Hopewell region. We base this on (1) X-ray diffraction analysis of quickly made smears, (2) spatiotemporal distribution of artifacts in the Sterling-Rock Falls, Illinois area, and (3) petrographic, X-ray fluorescence, Mo??ssbauer, and SEM/EDX analyses. This understanding of the source of this material made it possible to visually identify the source of large numbers of curated artifacts as having been made of material from the Sterling-Rock Falls area. This discovery has implications for understanding cultural and material exchange among Hopewellian societies. Also, it is the first report of berthierine flint clay and of flint clay that formed before the evolution of terrestrial plants. ?? 1998 John Wiley & Sons, Inc.

Langmuir-Blodgett films of random copolymers of fluoroalkyl(meth)acrylate and methacrylic acid: Fabrication and X-ray diffraction study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Safronov, V.; Feigin, L.A.; Budovskaya, L.D.

1994-12-31

Langmuir-Blodgett films of amphiphilic fluorinated copolymers were fabricated and studied by X-ray diffraction. Although these films show poor interlayer periodicity, they possess a uniform thickness even in the case of very thin films of one bilayer (22 {angstrom}). This feature was used to obtain complex LB structures (superlattices) with alteration of copolymer and fatty acid bilayers. X-ray diffraction data proved the regular periodical organization of these structures and allowed to calculate electron density distribution across the superlattices.

Crystallization and preliminary X-ray diffraction study of the protealysin precursor belonging to the peptidase family M4

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gromova, T. Yu., E-mail: duk@img.ras.ru; Demidyuk, I. V.; Kostrov, S. V.

2008-09-15

A protealysin precursor (the enzyme of the peptidase family M4) was crystallized for the first time. The crystal-growth conditions were found, and single crystals of the protein with dimensions of 0.3-0.5 mm were grown. The preliminary X-ray diffraction study of the enzyme was performed. The protealysin precursor was shown to crystallize in two crystal modifications suitable for the X-ray diffraction study of the three-dimensional structure of the protein molecule at atomic resolution.

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kimminau, G; Nagler, B; Higginbotham, A

2008-06-19

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

Framework for three-dimensional coherent diffraction imaging by focused beam x-ray Bragg ptychography.

PubMed

Hruszkewycz, Stephan O; Holt, Martin V; Tripathi, Ash; Maser, Jörg; Fuoss, Paul H

2011-06-15

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

Growth, structural, thermal, linear and nonlinear optical and laser damage threshold studies of picolinium tartrate monohydrate single crystals.

PubMed

Peramaiyan, G; Pandi, P; Sornamurthy, B M; Bhagavannarayana, G; Mohan Kumar, R

2012-09-01

Picolinium tartrate monohydrate (PTM), a novel organic nonlinear optical material was synthesized and bulk crystals were grown from aqueous solution by slow cooling technique. The cell parameters of the grown crystal were found by single and powder X-ray diffraction analyses. The crystalline perfection of the grown crystals has been analyzed by high-resolution X-ray diffraction (HRXRD) rocking curve measurements. The presence of functional groups in the grown crystal was identified by FTIR and FT-Raman spectral analyses. UV-Vis spectral studies reveal PTM crystals are transparent in the wavelength region of 295-1100 nm. The thermal characteristics of PTM were analyzed by TGA/DTA studies. The dielectric and mechanical behaviours of PTM crystals were investigated. Dislocation density was estimated to be 2.89 × 10(3) cm(-2) on the flat-surface of PTM crystals from the etching studies. The laser induced surface damage threshold for the grown crystal was measured using Nd:YAG laser. Its second harmonic generation relative efficiency was measured by Kurtz and Perry powder technique and was observed to be comparable with KDP crystal. Copyright © 2012 Elsevier B.V. All rights reserved.

Growth, nonlinear optical, thermal, dielectric and laser damage threshold studies of semiorganic crystal: monohydrate piperazine hydrogen phosphate.

PubMed

Krishnan, P; Gayathri, K; Bhagavannarayana, G; Gunasekaran, S; Anbalagan, G

2013-02-01

Monohydrate piperazine hydrogen phosphate (MPHP), a semi organic nonlinear optical material has been synthesized and single crystals were grown from aqueous solution by slow evaporation technique. Single crystal X-ray diffraction study on grown crystal reveals that they belong to monoclinic crystal system with space group P2(1)/c; (a=6.39Å; b=12.22Å; c=11.16Å; β=97.14°; V=864Å(3)). The structural perfection of the grown crystal was analyzed by high-resolution X-ray diffraction (HRXRD) rocking curve measurements. FTIR spectrum confirms the presence of the functional groups in synthesized material. UV-Vis spectrum indicates that the crystal is transparent in the entire visible region with a lower cut off wavelength of 387 nm. The variation of dielectric properties of the grown crystal with respect to frequency has been investigated at different temperatures. Thermal analysis carried out on the MPHP crystal shows that the crystal is stable up to 135°C. Relative powder second harmonic generation efficiency tested by Kurtz-Perry powder technique, which was about 0.638 times that of Potassium dihydrogen phosphate. Copyright © 2012 Elsevier B.V. All rights reserved.

Three-dimensional imaging of nanoscale materials by using coherent x-rays

DOE Office of Scientific and Technical Information (OSTI.GOV)

Miao, Jianwei

X-ray crystallography is currently the primary methodology used to determine the 3D structure of materials and macromolecules. However, many nanostructures, disordered materials, biomaterials, hybrid materials and biological specimens are noncrystalline and, hence, their structures are not accessible by X-ray crystallography. Probing these structures therefore requires the employment of different approaches. A very promising technique currently under rapid development is X-ray diffraction microscopy (or lensless imaging), in which the coherent X-ray diffraction pattern of a noncrystalline specimen is measured and then directly phased to obtain a high-resolution image. Through the DOE support over the past three years, we have applied X-raymore » diffraction microscopy to quantitative imaging of GaN quantum dot particles, and revealed the internal GaN-Ga2O3 core shell structure in three dimensions. By exploiting the abrupt change in the scattering cross-section near electronic resonances, we carried out the first experimental demonstration of resonant X-ray diffraction microscopy for element specific imaging. We performed nondestructive and quantitative imaging of buried Bi structures inside a Si crystal by directly phasing coherent X-ray diffraction patterns acquired below and above the Bi M5 edge. We have also applied X-ray diffraction microscopy to nondestructive imaging of mineral crystals inside biological composite materials - intramuscular fish bone - at the nanometer scale resolution. We identified mineral crystals in collagen fibrils at different stages of mineralization and proposed a dynamic mechanism to account for the nucleation and growth of mineral crystals in the collagen matrix. In addition, we have also discovered a novel 3D imaging modality, denoted ankylography, which allows for complete 3D structure determination without the necessity of sample titling or scanning. We showed that when the diffraction pattern of a finite object is sampled at a sufficiently fine scale on the Ewald sphere, the 3D structure of the object is determined by the 2D spherical pattern. We confirmed the theoretical analysis by performing 3D numerical reconstructions of a sodium silicate glass structure at 2 A resolution from a 2D spherical diffraction pattern alone. As X-ray free electron lasers are under rapid development worldwide, ankylography may open up a new horizon to obtain the 3D structure of a non-crystalline specimen from a single pulse and allow time-resolved 3D structure determination of disordered materials.« less

X-ray rocking curve measurements of bent crystals. [used in High Resolution Spectrometer in Advanced X-ray Astrophysics Facility

NASA Technical Reports Server (NTRS)

Hakim, M. B.; Muney, W. S.; Fowler, W. B.; Woodgate, B. E.

1988-01-01

A three-crystal laboratory X-ray spectrometer is used to measure the Bragg reflection from concave cylindrically curved crystals to be used in the high-resolution X-ray spectrometer of the NASA Advanced X-ray Astrophysics Facility (AXAF). The first two crystals, in the dispersive (1.1) arrangement, select a narrow collimated monochromatic beam in the Cu K-alpha(1) line at 1.5 A (8.1 keV), which illuminates the test crystal. The angular centroids of rocking curves measured along the surface provide a measure of the conformity of the crystal to the desired radius of curvature. Individual and combined rocking-curve widths and areas provide a measure of the resolution and efficiency at 1.54 A. The crystals analyzed included LiF(200), PET, and acid phthalates such as TAP.

Microfluidic Chips for In Situ Crystal X-ray Diffraction and In Situ Dynamic Light Scattering for Serial Crystallography.

PubMed

Gicquel, Yannig; Schubert, Robin; Kapis, Svetlana; Bourenkov, Gleb; Schneider, Thomas; Perbandt, Markus; Betzel, Christian; Chapman, Henry N; Heymann, Michael

2018-04-24

This protocol describes fabricating microfluidic devices with low X-ray background optimized for goniometer based fixed target serial crystallography. The devices are patterned from epoxy glue using soft lithography and are suitable for in situ X-ray diffraction experiments at room temperature. The sample wells are lidded on both sides with polymeric polyimide foil windows that allow diffraction data collection with low X-ray background. This fabrication method is undemanding and inexpensive. After the sourcing of a SU-8 master wafer, all fabrication can be completed outside of a cleanroom in a typical research lab environment. The chip design and fabrication protocol utilize capillary valving to microfluidically split an aqueous reaction into defined nanoliter sized droplets. This loading mechanism avoids the sample loss from channel dead-volume and can easily be performed manually without using pumps or other equipment for fluid actuation. We describe how isolated nanoliter sized drops of protein solution can be monitored in situ by dynamic light scattering to control protein crystal nucleation and growth. After suitable crystals are grown, complete X-ray diffraction datasets can be collected using goniometer based in situ fixed target serial X-ray crystallography at room temperature. The protocol provides custom scripts to process diffraction datasets using a suite of software tools to solve and refine the protein crystal structure. This approach avoids the artefacts possibly induced during cryo-preservation or manual crystal handling in conventional crystallography experiments. We present and compare three protein structures that were solved using small crystals with dimensions of approximately 10-20 µm grown in chip. By crystallizing and diffracting in situ, handling and hence mechanical disturbances of fragile crystals is minimized. The protocol details how to fabricate a custom X-ray transparent microfluidic chip suitable for in situ serial crystallography. As almost every crystal can be used for diffraction data collection, these microfluidic chips are a very efficient crystal delivery method.

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

NASA Technical Reports Server (NTRS)

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

2000-01-01

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

Specimen preparation for cryogenic coherent X-ray diffraction imaging of biological cells and cellular organelles by using the X-ray free-electron laser at SACLA

PubMed Central

Kobayashi, Amane; Sekiguchi, Yuki; Oroguchi, Tomotaka; Okajima, Koji; Fukuda, Asahi; Oide, Mao; Yamamoto, Masaki; Nakasako, Masayoshi

2016-01-01

Coherent X-ray diffraction imaging (CXDI) allows internal structures of biological cells and cellular organelles to be analyzed. CXDI experiments have been conducted at 66 K for frozen-hydrated biological specimens at the SPring-8 Angstrom Compact Free-Electron Laser facility (SACLA). In these cryogenic CXDI experiments using X-ray free-electron laser (XFEL) pulses, specimen particles dispersed on thin membranes of specimen disks are transferred into the vacuum chamber of a diffraction apparatus. Because focused single XFEL pulses destroy specimen particles at the atomic level, diffraction patterns are collected through raster scanning the specimen disks to provide fresh specimen particles in the irradiation area. The efficiency of diffraction data collection in cryogenic experiments depends on the quality of the prepared specimens. Here, detailed procedures for preparing frozen-hydrated biological specimens, particularly thin membranes and devices developed in our laboratory, are reported. In addition, the quality of the frozen-hydrated specimens are evaluated by analyzing the characteristics of the collected diffraction patterns. Based on the experimental results, the internal structures of the frozen-hydrated specimens and the future development for efficient diffraction data collection are discussed. PMID:27359147

Specimen preparation for cryogenic coherent X-ray diffraction imaging of biological cells and cellular organelles by using the X-ray free-electron laser at SACLA.

PubMed

Kobayashi, Amane; Sekiguchi, Yuki; Oroguchi, Tomotaka; Okajima, Koji; Fukuda, Asahi; Oide, Mao; Yamamoto, Masaki; Nakasako, Masayoshi

2016-07-01

Coherent X-ray diffraction imaging (CXDI) allows internal structures of biological cells and cellular organelles to be analyzed. CXDI experiments have been conducted at 66 K for frozen-hydrated biological specimens at the SPring-8 Angstrom Compact Free-Electron Laser facility (SACLA). In these cryogenic CXDI experiments using X-ray free-electron laser (XFEL) pulses, specimen particles dispersed on thin membranes of specimen disks are transferred into the vacuum chamber of a diffraction apparatus. Because focused single XFEL pulses destroy specimen particles at the atomic level, diffraction patterns are collected through raster scanning the specimen disks to provide fresh specimen particles in the irradiation area. The efficiency of diffraction data collection in cryogenic experiments depends on the quality of the prepared specimens. Here, detailed procedures for preparing frozen-hydrated biological specimens, particularly thin membranes and devices developed in our laboratory, are reported. In addition, the quality of the frozen-hydrated specimens are evaluated by analyzing the characteristics of the collected diffraction patterns. Based on the experimental results, the internal structures of the frozen-hydrated specimens and the future development for efficient diffraction data collection are discussed.

Low orthopyroxene from a lunar deep crustal rock - A new pyroxene polymorph of space group P21ca

NASA Technical Reports Server (NTRS)

Smyth, J. R.

1974-01-01

Bronzite crystals (En86Fs11Wo3) from a slowly-cooled lunar troctolitic granulite, have space group P21ca, a postulated, but previously unreported space group. Diffractions violating the b-glide extinction conditions have been observed in long-exposure X-ray precession photographs from three of these crystals and on an automated X-ray diffractometer. P21ca is a subgroup of the common orthopyroxene space group Pbca, and its cell dimensions (a = 18.235 plus or minus 0.004 A, b = 8.831 plus or minus 0.002 A, c = 5.189 plus or minus 0.001 A) are similar to those of terrestrial bronzites. It is postulated that the lower symmetry space group has developed as a result of very slow cooling at pressures of one to two kilobars deep in the lunar crust.

Growth and characterizations of various GaN nanostructures on C-plane sapphire using laser MBE

NASA Astrophysics Data System (ADS)

Ch., Ramesh; Tyagi, P.; Maurya, K. K.; Kumar, M. Senthil; Kushvaha, S. S.

2017-05-01

We have grown various GaN nanostructures such as three-dimensional islands, nanowalls and nanocolumns on c-plane sapphire substrates using laser assisted molecular beam epitaxy (LMBE) system. The shape of the GaN nanostructures was controlled by using different nucleation surfaces such as bare and nitridated sapphire with GaN or AlN buffer layers. The structural and surface morphological properties of grown GaN nanostructures were characterized by ex-situ high resolution x-ray diffraction, Raman spectroscopy and field emission scanning electron microscopy. The symmetric x-ray rocking curve along GaN (0002) plane shows that the GaN grown on pre-nitridated sapphire with GaN or AlN buffer layer possesses good crystalline quality compared to sapphire without nitridation. The Raman spectroscopy measurements revealed the wurtzite phase for all the GaN nanostructures grown on c-sapphire.

Emerging opportunities in structural biology with X-ray free-electron lasers

PubMed Central

Schlichting, Ilme; Miao, Jianwei

2012-01-01

X-ray free-electron lasers (X-FELs) produce X-ray pulses with extremely brilliant peak intensity and ultrashort pulse duration. It has been proposed that radiation damage can be “outrun” by using an ultra intense and short X-FEL pulse that passes a biological sample before the onset of significant radiation damage. The concept of “diffraction-before-destruction” has been demonstrated recently at the Linac Coherent Light Source, the first operational hard X-ray FEL, for protein nanocrystals and giant virus particles. The continuous diffraction patterns from single particles allow solving the classical “phase problem” by the oversampling method with iterative algorithms. If enough data are collected from many identical copies of a (biological) particle, its three-dimensional structure can be reconstructed. We review the current status and future prospects of serial femtosecond crystallography (SFX) and single-particle coherent diffraction imaging (CDI) with X-FELs. PMID:22922042

Publications - GMC 58 | Alaska Division of Geological & Geophysical Surveys

Science.gov Websites

DGGS GMC 58 Publication Details Title: X-ray diffraction and scanning electron microscopy mineral , Michael, and Core Laboratories, 1985, X-ray diffraction and scanning electron microscopy mineral analyses

Observation of divergent-beam X-ray diffraction from a crystal of diamond using synchrotron radiation.

PubMed

Glazer, A M; Collins, S P; Zekria, D; Liu, J; Golshan, M

2004-03-01

In 1947 Kathleen Lonsdale conducted a series of experiments on X-ray diffraction using a divergent beam external to a crystal sample. Unlike the Kossel technique, where divergent X-rays are excited by the presence of fluorescing atoms within the crystal, the use of an external divergent source made it possible to study non-fluorescing crystals. The resulting photographs not only illustrated the complexity of X-ray diffraction from crystals in a truly beautiful way, but also demonstrated unprecedented experimental precision. This long-forgotten work is repeated here using a synchrotron radiation source and, once again, considerable merit is found in Lonsdale's technique. The results of this experiment suggest that, through the use of modern 'third-generation' synchrotron sources, divergent-beam diffraction could soon enjoy a renaissance for high-precision lattice-parameter determination and the study of crystal perfection.

Soft X-ray spectromicroscopy using ptychography with randomly phased illumination

NASA Astrophysics Data System (ADS)

Maiden, A. M.; Morrison, G. R.; Kaulich, B.; Gianoncelli, A.; Rodenburg, J. M.

2013-04-01

Ptychography is a form of scanning diffractive imaging that can successfully retrieve the modulus and phase of both the sample transmission function and the illuminating probe. An experimental difficulty commonly encountered in diffractive imaging is the large dynamic range of the diffraction data. Here we report a novel ptychographic experiment using a randomly phased X-ray probe to considerably reduce the dynamic range of the recorded diffraction patterns. Images can be reconstructed reliably and robustly from this setup, even when scatter from the specimen is weak. A series of ptychographic reconstructions at X-ray energies around the L absorption edge of iron demonstrates the advantages of this method for soft X-ray spectromicroscopy, which can readily provide chemical sensitivity without the need for optical refocusing. In particular, the phase signal is in perfect registration with the modulus signal and provides complementary information that can be more sensitive to changes in the local chemical environment.

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

PubMed

Duarte, Íris; Andrade, Rita; Pinto, João F; Temtem, Márcio

2016-09-01

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].

Submicron x-ray diffraction and its applications to problems in materials and environmental science

NASA Astrophysics Data System (ADS)

Tamura, N.; Celestre, R. S.; MacDowell, A. A.; Padmore, H. A.; Spolenak, R.; Valek, B. C.; Meier Chang, N.; Manceau, A.; Patel, J. R.

2002-03-01

The availability of high brilliance third generation synchrotron sources together with progress in achromatic focusing optics allows us to add submicron spatial resolution to the conventional century-old x-ray diffraction technique. The new capabilities include the possibility to map in situ, grain orientations, crystalline phase distribution, and full strain/stress tensors at a very local level, by combining white and monochromatic x-ray microbeam diffraction. This is particularly relevant for high technology industry where the understanding of material properties at a microstructural level becomes increasingly important. After describing the latest advances in the submicron x-ray diffraction techniques at the Advanced Light Source, we will give some examples of its application in material science for the measurement of strain/stress in metallic thin films and interconnects. Its use in the field of environmental science will also be discussed.

Ultrahigh vacuum/high pressure chamber for surface x-ray diffraction experiments

NASA Astrophysics Data System (ADS)

Bernard, P.; Peters, K.; Alvarez, J.; Ferrer, S.

1999-02-01

We describe an ultrahigh vacuum chamber that can be internally pressurized to several bars and that is designed to perform surface x-ray diffraction experiments on solid-gas interfaces. The chamber has a cylindrical beryllium window that serves as the entrance and exit for the x rays. The sample surface can be ion bombarded with an ancillary ion gun and annealed to 1200 K.

Symposium LL: Nanowires--Synthesis Properties Assembly and Application

DTIC Science & Technology

2010-09-10

dedicated hard x - ray microscopy beamline is operated in partnership with the Advanced Photon Source to provide fluorescence, diffraction, and...characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X - ray diffraction (XRD) measurements, proving it to be...Investigation of Preferred Growth Direction of GaN Nanorods by Synchrotron X - ray Reciprocal Space Mapping. Yuri Sohn1, Sanghwa Lee1, Chinkyo Kim1 and Dong

X-ray diffraction-based electronic structure calculations and experimental x-ray analysis for medical and materials applications

NASA Astrophysics Data System (ADS)

Mahato, Dip Narayan

This thesis includes x-ray experiments for medical and materials applications and the use of x-ray diffraction data in a first-principles study of electronic structures and hyperfine properties of chemical and biological systems. Polycapillary focusing lenses were used to collect divergent x rays emitted from conventional x-ray tubes and redirect them to form an intense focused beam. These lenses are routinely used in microbeam x-ray fluorescence analysis. In this thesis, their potential application to powder diffraction and focused beam orthovoltage cancer therapy has been investigated. In conventional x-ray therapy, very high energy (˜ MeV) beams are used, partly to reduce the skin dose. For any divergent beam, the dose is necessarily highest at the entry point, and decays exponentially into the tissue. To reduce the skin dose, high energy beams, which have long absorption lengths, are employed, and rotated about the patient to enter from different angles. This necessitates large expensive specialized equipment. A focused beam could concentrate the dose within the patient. Since this is inherently skin dose sparing, lower energy photons could be employed. A primary concern in applying focused beams to therapy is whether the focus would be maintained despite Compton scattering within the tissue. To investigate this, transmission and focal spot sizes as a function of photon energy of two polycapillary focusing lenses were measured. The effects of tissue-equivalent phantoms of different thicknesses on the focal spot size were studied. Scatter fraction and depth dose were calculated. For powder diffraction, the polycapillary optics provide clean Gaussian peaks, which result in angular resolution that is much smaller than the peak width due to the beam convergence. Powder diffraction (also called coherent scatter) without optics can also be used to distinguish between tissue types that, because they have different nanoscale structures, scatter at different angles. Measurements were performed on the development of coherent scatter imaging to provide tissue type information in mammography. Atomic coordinates from x-ray diffraction data were used to study the nuclear quadrupole interactions and nature of molecular binding in DNA/RNA nucleobases and molecular solid BF3 systems.

Curved focusing crystals for hard X-ray astronomy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ferrari, C., E-mail: ferrari@imem.cnr.it; Buffagni, E.; Bonnini, E.

A lens made by a properly arranged array of crystals can be used to focus x-rays of energy ranging from 30 to 500 keV for x-ray astronomy. Mosaic or curved crystals can be employed as x-ray optical elements. In this work self standing curved focusing Si and GaAs crystals in which the lattice bending is induced by a controlled damaging process on one side of planar crystals are characterized. Diffraction profiles in Laue geometry have been measured in crystals at x-ray energies E = 17, 59 and 120 keV. An enhancement of diffraction efficiency is found in asymmetric geometries.

Sealed-tube synthesis and phase diagram of Li{sub x}TiS{sub 2} (0 ≤ x ≤1)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Ziping; National Laboratory for Superconductivity, Institute of Physics, Chinese Academy of Science, Beijing 100190; Dong, Cheng, E-mail: chengdon@aphy.iphy.ac.cn

2015-01-15

Graphical abstract: We reported a new method to prepare Li{sub x}TiS{sub 2} (0 ≤ x ≤ 1) at 600 °C in sealed tube using Li{sub 2}S aslithium source. A schematic phase diagram of the Li{sub x}TiS{sub 2} system has been constructed based on the DTA and XRD data. - Abstract: We reported a new method to prepare Li{sub x}TiS{sub 2} (0 ≤ x ≤ 1) at 600 °C in sealed tube using Li{sub 2}S as lithium source. The Li{sub x}TiS{sub 2} samples were characterized by powder X-ray diffraction, scanning electron microscopy, energy dispersive X-ray spectroscopy, and differential thermal analysis. Themore » variations of the lattice parameters with lithium content x in Li{sub x}TiS{sub 2} were determined by X-ray powder diffraction analysis for both 1T and 3R phases. The phase transition between low-temperature 1T phase and high-temperature 3R phase was confirmed by the powder X-ray diffraction analysis. Based on the differential thermal analysis and X-ray diffraction results, a schematic phase diagram of the Li{sub x}TiS{sub 2} system has been constructed, providing a guideline to synthesize Li{sub x}TiS{sub 2} in 1T structure or 3R structure.« less

X-ray diffraction on radioactive materials

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schiferl, D.; Roof, R.B.

1978-01-01

X-ray diffraction studies on radioactive materials are discussed with the aim of providing a guide to new researchers in the field. Considerable emphasis is placed on the safe handling and loading of not-too-exotic samples. Special considerations such as the problems of film blackening by the gamma rays and changes induced by the self-irradiation of the sample are covered. Some modifications of common diffraction techniques are presented. Finally, diffraction studies on radioactive samples under extreme conditions are discussed, with primary emphasis on high-pressure studies involving diamond-anvil cells.

Analytical characterization of a new mobile X-ray fluorescence and X-ray diffraction instrument combined with a pigment identification case study

NASA Astrophysics Data System (ADS)

Van de Voorde, Lien; Vekemans, Bart; Verhaeven, Eddy; Tack, Pieter; De Wolf, Robin; Garrevoet, Jan; Vandenabeele, Peter; Vincze, Laszlo

2015-08-01

A new, commercially available, mobile system combining X-ray diffraction and X-ray fluorescence has been evaluated which enables both elemental analysis and phase identification simultaneously. The instrument makes use of a copper or molybdenum based miniature X-ray tube and a silicon-Pin diode energy-dispersive detector to count the photons originating from the samples. The X-ray tube and detector are both mounted on an X-ray diffraction protractor in a Bragg-Brentano θ:θ geometry. The mobile instrument is one of the lightest and most compact instruments of its kind (3.5 kg) and it is thus very useful for in situ purposes such as the direct (non-destructive) analysis of cultural heritage objects which need to be analyzed on site without any displacement. The supplied software allows both the operation of the instrument for data collection and in-depth data analysis using the International Centre for Diffraction Data database. This paper focuses on the characterization of the instrument, combined with a case study on pigment identification and an illustrative example for the analysis of lead alloyed printing letters. The results show that this commercially available light-weight instrument is able to identify the main crystalline phases non-destructively, present in a variety of samples, with a high degree of flexibility regarding sample size and position.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sun, Cheng-Jun, E-mail: cjsun@aps.anl.gov; Brewe, Dale L.; Heald, Steve M.

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

A von Hamos x-ray spectrometer based on a segmented-type diffraction crystal for single-shot x-ray emission spectroscopy and time-resolved resonant inelastic x-ray scattering studies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Szlachetko, J.; Institute of Physics, Jan Kochanowski University, 25-406 Kielce; Nachtegaal, M.

2012-10-15

We report on the design and performance of a wavelength-dispersive type spectrometer based on the von Hamos geometry. The spectrometer is equipped with a segmented-type crystal for x-ray diffraction and provides an energy resolution in the order of 0.25 eV and 1 eV over an energy range of 8000 eV-9600 eV. The use of a segmented crystal results in a simple and straightforward crystal preparation that allows to preserve the spectrometer resolution and spectrometer efficiency. Application of the spectrometer for time-resolved resonant inelastic x-ray scattering and single-shot x-ray emission spectroscopy is demonstrated.

A multi-dataset data-collection strategy produces better diffraction data

PubMed Central

Liu, Zhi-Jie; Chen, Lirong; Wu, Dong; Ding, Wei; Zhang, Hua; Zhou, Weihong; Fu, Zheng-Qing; Wang, Bi-Cheng

2011-01-01

A multi-dataset (MDS) data-collection strategy is proposed and analyzed for macromolecular crystal diffraction data acquisition. The theoretical analysis indicated that the MDS strategy can reduce the standard deviation (background noise) of diffraction data compared with the commonly used single-dataset strategy for a fixed X-ray dose. In order to validate the hypothesis experimentally, a data-quality evaluation process, termed a readiness test of the X-ray data-collection system, was developed. The anomalous signals of sulfur atoms in zinc-free insulin crystals were used as the probe to differentiate the quality of data collected using different data-collection strategies. The data-collection results using home-laboratory-based rotating-anode X-ray and synchrotron X-ray systems indicate that the diffraction data collected with the MDS strategy contain more accurate anomalous signals from sulfur atoms than the data collected with a regular data-collection strategy. In addition, the MDS strategy offered more advantages with respect to radiation-damage-sensitive crystals and better usage of rotating-anode as well as synchrotron X-rays. PMID:22011470

Effects of rare-earth co-doping on the local structure of rare-earth phosphate glasses using high and low energy X-ray diffraction.

PubMed

Cramer, Alisha J; Cole, Jacqueline M; FitzGerald, Vicky; Honkimaki, Veijo; Roberts, Mark A; Brennan, Tessa; Martin, Richard A; Saunders, George A; Newport, Robert J

2013-06-14

Rare-earth co-doping in inorganic materials has a long-held tradition of facilitating highly desirable optoelectronic properties for their application to the laser industry. This study concentrates specifically on rare-earth phosphate glasses, (R2O3)x(R'2O3)y(P2O5)(1-(x+y)), where (R, R') denotes (Ce, Er) or (La, Nd) co-doping and the total rare-earth composition corresponds to a range between metaphosphate, RP3O9, and ultraphosphate, RP5O14. Thereupon, the effects of rare-earth co-doping on the local structure are assessed at the atomic level. Pair-distribution function analysis of high-energy X-ray diffraction data (Q(max) = 28 Å(-1)) is employed to make this assessment. Results reveal a stark structural invariance to rare-earth co-doping which bears testament to the open-framework and rigid nature of these glasses. A range of desirable attributes of these glasses unfold from this finding; in particular, a structural simplicity that will enable facile molecular engineering of rare-earth phosphate glasses with 'dial-up' lasing properties. When considered together with other factors, this finding also demonstrates additional prospects for these co-doped rare-earth phosphate glasses in nuclear waste storage applications. This study also reveals, for the first time, the ability to distinguish between P-O and P[double bond, length as m-dash]O bonding in these rare-earth phosphate glasses from X-ray diffraction data in a fully quantitative manner. Complementary analysis of high-energy X-ray diffraction data on single rare-earth phosphate glasses of similar rare-earth composition to the co-doped materials is also presented in this context. In a technical sense, all high-energy X-ray diffraction data on these glasses are compared with analogous low-energy diffraction data; their salient differences reveal distinct advantages of high-energy X-ray diffraction data for the study of amorphous materials.

{ital In-situ} x-ray investigation of hydrogen charging in thin film bimetallic electrodes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jisrawi, N.M.; Wiesmann, H.; Ruckman, M.W.

Hydrogen uptake and discharge by thin metallic films under potentiostatic control was studied using x-ray diffraction at the National Synchrotron Light Source (NSLS). The formation of metal-hydrogen phases in Pd, Pd-capped Nb and Pd/Nb multilayer electrode structures was deduced from x-ray diffraction data and correlated with the cyclic voltammetry (CV) peaks. The x-ray data was also used to construct a plot of the hydrogen concentration as a function of cell potential for a multilayered thin film. {copyright} {ital 1997 Materials Research Society.}

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

PubMed

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.

Rosalind Franklin's X-ray photo of DNA as an undergraduate optical diffraction experiment

NASA Astrophysics Data System (ADS)

Thompson, J.; Braun, G.; Tierney, D.; Wessels, L.; Schmitzer, H.; Rossa, B.; Wagner, H. P.; Dultz, W.

2018-02-01

Rosalind Franklin's X-ray diffraction patterns of DNA molecules rendered the important clue that DNA has the structure of a double helix. The most famous X-ray photograph, Photo 51, is still printed in most Biology textbooks. We suggest two optical experiments for undergraduates that make this historic achievement comprehensible for students by using macromodels of DNA and visible light to recreate a diffraction pattern similar to Photo 51. In these macromodels, we replace the double helix both mathematically and experimentally with its two-dimensional (flat) projection and explain why this is permissible. Basic optical concepts are used to infer certain well-known characteristics of DNA from the diffraction pattern.

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

DOE PAGES

Awel, Salah; Kirian, Richard A.; Wiedorn, Max O.; ...

2018-02-01

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

Incoherent Diffractive Imaging via Intensity Correlations of Hard X Rays

NASA Astrophysics Data System (ADS)

Classen, Anton; Ayyer, Kartik; Chapman, Henry N.; Röhlsberger, Ralf; von Zanthier, Joachim

2017-08-01

Established x-ray diffraction methods allow for high-resolution structure determination of crystals, crystallized protein structures, or even single molecules. While these techniques rely on coherent scattering, incoherent processes like fluorescence emission—often the predominant scattering mechanism—are generally considered detrimental for imaging applications. Here, we show that intensity correlations of incoherently scattered x-ray radiation can be used to image the full 3D arrangement of the scattering atoms with significantly higher resolution compared to conventional coherent diffraction imaging and crystallography, including additional three-dimensional information in Fourier space for a single sample orientation. We present a number of properties of incoherent diffractive imaging that are conceptually superior to those of coherent methods.

Titration of a Solid Acid Monitored by X-Ray Diffraction

ERIC Educational Resources Information Center

Dungey, Keenan E.; Epstein, Paul

2007-01-01

An experiment is described to introduce students to an important class of solid-state reactions while reinforcing concepts of titration by using a pH meter and a powder X-ray diffractometer. The experiment was successful in teaching students the abstract concepts of solid-state structure and diffraction by applying the diffraction concepts learned…

Publications - GMC 42 | Alaska Division of Geological & Geophysical Surveys

Science.gov Websites

DGGS GMC 42 Publication Details Title: X-ray diffraction clay mineralogy analysis of the J.W. Dalton #1 for more information. Bibliographic Reference Unknown, 1984, X-ray diffraction clay mineralogy

Publications - GMC 297 | Alaska Division of Geological & Geophysical

Science.gov Websites

DGGS GMC 297 Publication Details Title: X-ray diffraction analysis of cuttings from the: Texaco Inc information. Bibliographic Reference Unknown, 2001, X-ray diffraction analysis of cuttings from the: Texaco

Publications - GMC 196 | Alaska Division of Geological & Geophysical

Science.gov Websites

DGGS GMC 196 Publication Details Title: X-ray diffraction patterns of clay from the following wells for more information. Bibliographic Reference Unknown, 1992, X-ray diffraction patterns of clay from

Publications - GMC 43 | Alaska Division of Geological & Geophysical Surveys

Science.gov Websites

DGGS GMC 43 Publication Details Title: X-ray diffraction clay mineralogy analysis of 23 North Slope more information. Bibliographic Reference Unknown, 1983, X-ray diffraction clay mineralogy analysis of

Multiple film plane diagnostic for shocked lattice measurements (invited)

NASA Astrophysics Data System (ADS)

Kalantar, Daniel H.; Bringa, E.; Caturla, M.; Colvin, J.; Lorenz, K. T.; Kumar, M.; Stölken, J.; Allen, A. M.; Rosolankova, K.; Wark, J. S.; Meyers, M. A.; Schneider, M.; Boehly, T. R.

2003-03-01

Laser-based shock experiments have been conducted in thin Si and Cu crystals at pressures above the Hugoniot elastic limit. In these experiments, static film and x-ray streak cameras recorded x rays diffracted from lattice planes both parallel and perpendicular to the shock direction. These data showed uniaxial compression of Si(100) along the shock direction and three-dimensional compression of Cu(100). In the case of the Si diffraction, there was a multiple wave structure observed, which may be due to a one-dimensional phase transition or a time variation in the shock pressure. A new film-based detector has been developed for these in situ dynamic diffraction experiments. This large-angle detector consists of three film cassettes that are positioned to record x rays diffracted from a shocked crystal anywhere within a full π steradian. It records x rays that are diffracted from multiple lattice planes both parallel and at oblique angles with respect to the shock direction. It is a time-integrating measurement, but time-resolved data may be recorded using a short duration laser pulse to create the diffraction source x rays. This new instrument has been fielded at the OMEGA and Janus lasers to study single-crystal materials shock compressed by direct laser irradiation. In these experiments, a multiple wave structure was observed on many different lattice planes in Si. These data provide information on the structure under compression.

Sojourner APXS at Shark

NASA Image and Video Library

1997-08-28

NASA's Sojourner rover is seen next to the rock "Shark," in this image taken by the Imager for Mars Pathfinder (IMP) near the end of daytime operations on Sol 52. The rover's Alpha Proton X-Ray Spectrometer is deployed against the rock. The rock "Wedge" is in the foreground. The Sojourner rover is seen next to the rock "Shark," in this image taken by the Imager for Mars Pathfinder (IMP) near the end of daytime operations on Sol 52. The rover's Alpha Proton X-Ray Spectrometer is deployed against the rock. The rock "Wedge" is in the foreground.

Nanomodulated electron beams via electron diffraction and emittance exchange for coherent x-ray generation

NASA Astrophysics Data System (ADS)

Nanni, E. A.; Graves, W. S.; Moncton, D. E.

2018-01-01

We present a new method for generation of relativistic electron beams with current modulation on the nanometer scale and below. The current modulation is produced by diffracting relativistic electrons in single crystal Si, accelerating the diffracted beam and imaging the crystal structure, then transferring the image into the temporal dimension via emittance exchange. The modulation period can be tuned by adjusting electron optics after diffraction. This tunable longitudinal modulation can have a period as short as a few angstroms, enabling production of coherent hard x-rays from a source based on inverse Compton scattering with total accelerator length of approximately ten meters. Electron beam simulations from cathode emission through diffraction, acceleration, and image formation with variable magnification are presented along with estimates of the coherent x-ray output properties.

Theoretical calculation of coherent Laue-case conversion between x-rays and ALPs for an x-ray light-shining-through-a-wall experiment

NASA Astrophysics Data System (ADS)

Yamaji, T.; Yamazaki, T.; Tamasaku, K.; Namba, T.

2017-12-01

Single crystals have high atomic electric fields as much as 1 011 V /m , which correspond to magnetic fields of ˜103 T . These fields can be utilized to convert x-rays into axionlike particles (ALPs) coherently similar to x-ray diffraction. In this paper, we perform the first theoretical calculation of the Laue-case conversion in crystals based on the Darwin dynamical theory of x-ray diffraction. The calculation shows that the Laue-case conversion has longer interaction length than the Bragg case, and that ALPs in the keV range can be resonantly converted by tuning an incident angle of x-rays. ALPs with mass up to O (10 keV ) can be searched by light-shining-through-a-wall (LSW) experiments at synchrotron x-ray facilities.

'McKittrick' Rich in Sulfur

NASA Technical Reports Server (NTRS)

2004-01-01

These plots, or spectra, show that a rock dubbed 'McKittrick' near the Mars Exploration Rover Opportunity's landing site at Meridiani Planum, Mars, possesses the highest concentration of sulfur yet observed on Mars. These data were acquired with the rover's alpha particle X-ray spectrometer, which produces a spectrum, or fingerprint, of chemicals in martian rocks and soil. This instrument contains a radioisotope, curium-244, that bombards a designated area with alpha particles and X-rays, causing a cascade of reflective fluorescent X-rays. The energies of these fluorescent X-rays are unique to each atom in the periodic table, allowing scientists to determine a target's elemental composition.

The spectra shown here are taken from 'McKittrick' and a soil patch nicknamed 'Tarmac,' both of which are located within the small crater where Opportunity landed. 'McKittrick' measurements were acquired after the rover drilled a hole in the rock with its rock abrasion tool. Only portions of the targets' full spectra are displayed. The data are expressed as X-ray intensity (linear scale) versus energy. The measured area is 28 millimeters (1 inch) in diameter.

When comparing two spectra, the relative intensities at a given energy are proportional to the elemental concentrations, however these proportionality factors can be complex. To be precise, scientists extensively calibrate the instrument using well-analyzed geochemical standards.

Both the alpha particle X-ray spectrometer and the rock abrasion tool are located on the rover's instrument deployment device, or arm.

X-ray phase Identification of Chocolate is Possible

DOE Office of Scientific and Technical Information (OSTI.GOV)

Guthrie,S.; Mazzanti, G.; Idziak, S.

2005-01-01

When examining chocolate samples by means of X-ray diffraction, it has become common practice for any sugar to be removed through repeated rinsing in cold water. While necessary in some cases, we show that it is possible to determine the phase of certain dark chocolate samples without sugar removal, through examination of distinctive X-ray diffraction peaks corresponding to lattice spacings of 3.98 and 3.70 Angstroms.

The effect of laser radiation on the diffraction of X-rays in crystals

NASA Astrophysics Data System (ADS)

Trushin, V. N.; Chuprunov, E. V.; Khokhlov, A. F.

1988-10-01

The effect of laser radiation on the intensity of the X-ray diffraction peaks of KDP, ADP, and CuSO4-5H2O crystals was studied experimentally. This intensity was found to increase as a function of the laser beam power. This result suggests that it is possible to use laser beams to control X-ray intensity in the crystals considered.

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

PubMed Central

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

2016-01-01

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

Near Edge X-Ray Absorption and X-Ray Photoelectron Diffraction Studies of the Structural Environment of Ge-Si Systems

NASA Astrophysics Data System (ADS)

Castrucci, P.; Gunnella, R.; Pinto, N.; Bernardini, R.; de Crescenzi, M.; Sacchi, M.

Near edge X-ray absorption spectroscopy (XAS), X-ray photoelectron diffraction (XPD) and Auger electron diffraction (AED) are powerful techniques for the qualitative study of the structural and electronic properties of several systems. The recent development of a multiple scattering approach to simulating experimental spectra opened a friendly way to the study of structural environments of solids and surfaces. This article reviews recent X-ray absorption experiments using synchrotron radiation which were performed at Ge L edges and core level electron diffraction measurements obtained using a traditional X-ray source from Ge core levels for ultrathin Ge films deposited on silicon substrates. Thermodynamics and surface reconstruction have been found to play a crucial role in the first stages of Ge growth on Si(001) and Si(111) surfaces. Both techniques show the occurrence of intermixing processes even for room-temperature-grown Ge/Si(001) samples and give a straightforward measurement of the overlayer tetragonal distortion. The effects of Sb as a surfactant on the Ge/Si(001) interface have also been investigated. In this case, evidence of layer-by-layer growth of the fully strained Ge overlayer with a reduced intermixing is obtained when one monolayer of Sb is predeposited on the surface.

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

PubMed

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

2013-11-01

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

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

NASA Astrophysics Data System (ADS)

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

2013-11-01

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

X-ray characterization of curved crystals for hard x-ray astronomy

NASA Astrophysics Data System (ADS)

Buffagni, Elisa; Bonnini, Elisa; Ferrari, Claudio; Virgilli, Enrico; Frontera, Filippo

2015-05-01

Among the methods to focus photons the diffraction in crystals results as one of the most effective for high energy photons. An assembling of properly oriented crystals can form a lens able to focus x-rays at high energy via Laue diffraction in transmission geometry; this is a Laue lens. The x-ray diffraction theory provides that the maximum diffraction efficiency is achieved in ideal mosaic crystals, but real mosaic crystals show diffraction efficiencies several times lower than the ideal case due to technological problems. An alternative and convenient approach is the use of curved crystals. We have recently optimized an efficient method based on the surface damage of crystals to produce self-standing uniformly curved Si, GaAs and Ge tiles of thickness up to 2-3 mm and curvature radii R down to a few meters. We show that, for curved diffracting planes, such crystals have a diffraction efficiency nearly forty times higher than the diffraction efficiency of perfect similar flat crystals, thus very close to that of ideal mosaic crystals. Moreover, in an alternative configuration where the diffracting planes are perpendicular to the curved ones, a focusing effect occurs and will be shown. These results were obtained for several energies between 17 and 120 keV with lab sources or at high energy facilities such as LARIX at Ferrara (Italy), ESRF at Grenoble (France), and ANKA at Karlsruhe (Germany).

Publications - GMC 95 | Alaska Division of Geological & Geophysical Surveys

Science.gov Websites

DGGS GMC 95 Publication Details Title: X-ray diffraction analysis of seven core samples from the information. Bibliographic Reference Bergman, S.C., and Stuart, C.J., 1988, X-ray diffraction analysis of

X-Ray Topography of Tetragonal Lysozyme Grown by the Temperature-Controlled Technique

NASA Technical Reports Server (NTRS)

Stojanoff, V.; Siddons, D. P.; Monaco, Lisa A.; Vekilov, Peter; Rosenberger, Franz

1997-01-01

Growth-induced defects in lysozyme crystals were observed by white-beam and monochromatic X-ray topography at the National Synchrotron Light Source (NSLS) at the Brookhaven National Laboratory (BNL). The topographic methods were non-destructive to the extent that traditional diffraction data collection could be performed to high resolution after topography. It was found that changes in growth parameters, defect concentration as detected by X-ray topography, and the diffraction quality obtainable from the crystals were all strongly correlated. In addition, crystals with fewer defects showed lower mosaicity and higher diffraction resolution as expected.

Crystallization and X-ray diffraction analysis of a catalytic domain of hyperthermophilic chitinase from Pyrococcus furiosus

PubMed Central

Mine, Shouhei; Nakamura, Tsutomu; Hirata, Kunio; Ishikawa, Kazuhiko; Hagihara, Yoshihisa; Uegaki, Koichi

2006-01-01

The crystallization and preliminary X-ray diffraction analysis of a catalytic domain of chitinase (PF1233 gene) from the hyperthermophilic archaeon Pyrococcus furiosus is reported. The recombinant protein, prepared using an Escherichia coli expression system, was crystallized by the hanging-drop vapour-diffusion method. An X-ray diffraction data set was collected at the undulator beamline BL44XU at SPring-8 to a resolution of 1.50 Å. The crystals belong to space group P212121, with unit-cell parameters a = 90.0, b = 92.8, c = 107.2 Å. PMID:16880559

Coded diffraction system in X-ray crystallography using a boolean phase coded aperture approximation

NASA Astrophysics Data System (ADS)

Pinilla, Samuel; Poveda, Juan; Arguello, Henry

2018-03-01

Phase retrieval is a problem present in many applications such as optics, astronomical imaging, computational biology and X-ray crystallography. Recent work has shown that the phase can be better recovered when the acquisition architecture includes a coded aperture, which modulates the signal before diffraction, such that the underlying signal is recovered from coded diffraction patterns. Moreover, this type of modulation effect, before the diffraction operation, can be obtained using a phase coded aperture, just after the sample under study. However, a practical implementation of a phase coded aperture in an X-ray application is not feasible, because it is computationally modeled as a matrix with complex entries which requires changing the phase of the diffracted beams. In fact, changing the phase implies finding a material that allows to deviate the direction of an X-ray beam, which can considerably increase the implementation costs. Hence, this paper describes a low cost coded X-ray diffraction system based on block-unblock coded apertures that enables phase reconstruction. The proposed system approximates the phase coded aperture with a block-unblock coded aperture by using the detour-phase method. Moreover, the SAXS/WAXS X-ray crystallography software was used to simulate the diffraction patterns of a real crystal structure called Rhombic Dodecahedron. Additionally, several simulations were carried out to analyze the performance of block-unblock approximations in recovering the phase, using the simulated diffraction patterns. Furthermore, the quality of the reconstructions was measured in terms of the Peak Signal to Noise Ratio (PSNR). Results show that the performance of the block-unblock phase coded apertures approximation decreases at most 12.5% compared with the phase coded apertures. Moreover, the quality of the reconstructions using the boolean approximations is up to 2.5 dB of PSNR less with respect to the phase coded aperture reconstructions.

X-ray absorption microtomography (microCT) and small beam diffraction mapping of sea urchin teeth.

PubMed

Stock, S R; Barss, J; Dahl, T; Veis, A; Almer, J D

2002-07-01

Two noninvasive X-ray techniques, laboratory X-ray absorption microtomography (microCT) and X-ray diffraction mapping, were used to study teeth of the sea urchin Lytechinus variegatus. MicroCT revealed low attenuation regions at near the tooth's stone part and along the carinar process-central prism boundary; this latter observation appears to be novel. The expected variation of Mg fraction x in the mineral phase (calcite, Ca(1-x)Mg(x)CO(3)) cannot account for all of the linear attenuation coefficient decrease in the two zones: this suggested that soft tissue is localized there. Transmission diffraction mapping (synchrotron X-radiation, 80.8 keV, 0.1 x 0.1mm(2) beam area, 0.1mm translation grid, image plate area detector) simultaneously probed variations in 3-D and showed that the crystal elements of the "T"-shaped tooth were very highly aligned. Diffraction patterns from the keel (adaxial web) and from the abaxial flange (containing primary plates and the stone part) differed markedly. The flange contained two populations of identically oriented crystal elements with lattice parameters corresponding to x=0.13 and x=0.32. The keel produced one set of diffraction spots corresponding to the lower x. The compositions were more or less equivalent to those determined by others for camarodont teeth, and the high Mg phase is expected to be disks of secondary mineral epitaxially related to the underlying primary mineral element. Lattice parameter gradients were not noted in the keel or flange. Taken together, the microCT and diffraction results indicated that there was a band of relatively high protein content, of up to approximately 0.25 volume fraction, in the central part of the flange and paralleling its adaxial and abaxial faces. X-ray microCT and microdiffraction data used in conjunction with protein distribution data will be crucial for understanding the properties of various biocomposites and their mechanical functions.

Reconstructive colour X-ray diffraction imaging--a novel TEDDI imaging method.

PubMed

Lazzari, Olivier; Jacques, Simon; Sochi, Taha; Barnes, Paul

2009-09-01

Tomographic Energy-Dispersive Diffraction Imaging (TEDDI) enables a unique non-destructive mapping of the interior of bulk objects, exploiting the full range of X-ray signals (diffraction, fluorescence, scattering, background) recorded. By analogy to optical imaging, a wide variety of features (structure, composition, orientation, strain) dispersed in X-ray wavelengths can be extracted and colour-coded to aid interpretation. The ultimate aim of this approach is to realise real-time high-definition colour X-ray diffraction imaging, on the timescales of seconds, so that one will be able to 'look inside' optically opaque apparatus and unravel the space/time-evolution of the materials chemistry taking place. This will impact strongly on many fields of science but there are currently two barriers to this goal: speed of data acquisition (a 2D scan currently takes minutes to hours) and loss of image definition through spatial distortion of the X-ray sampling volume. Here we present a data-collection scenario and reconstruction routine which overcomes the latter barrier and which has been successfully applied to a phantom test object and to real materials systems such as a carbonating cement block. These procedures are immediately transferable to the promising technology of multi-energy-dispersive-detector-arrays which are planned to deliver the other breakthrough, that of one-two orders of magnitude improvement in data acquisition rates, that will be needed to realise real-time high-definition colour X-ray diffraction imaging.

Nondestructive strain depth profiling with high energy X-ray diffraction: System capabilities and limitations

NASA Astrophysics Data System (ADS)

Zhang, Zhan; Wendt, Scott; Cosentino, Nicholas; Bond, Leonard J.

2018-04-01

Limited by photon energy, and penetration capability, traditional X-ray diffraction (XRD) strain measurements are only capable of achieving a few microns depth due to the use of copper (Cu Kα1) or molybdenum (Mo Kα1) characteristic radiation. For deeper strain depth profiling, destructive methods are commonly necessary to access layers of interest by removing material. To investigate deeper depth profiles nondestructively, a laboratory bench-top high-energy X-ray diffraction (HEXRD) system was previously developed. This HEXRD method uses an industrial 320 kVp X-Ray tube and the Kα1 characteristic peak of tungsten, to produces a higher intensity X-ray beam which enables depth profiling measurement of lattice strain. An aluminum sample was investigated with deformation/load provided using a bending rig. It was shown that the HEXRD method is capable of strain depth profiling to 2.5 mm. The method was validated using an aluminum sample where both the HEXRD method and the traditional X-ray diffraction method gave data compared with that obtained using destructive etching layer removal, performed by a commercial provider. The results demonstrate comparable accuracy up to 0.8 mm depth. Nevertheless, higher attenuation capabilities in heavier metals limit the applications in other materials. Simulations predict that HEXRD works for steel and nickel in material up to 200 µm, but experiment results indicate that the HEXRD strain profile is not practical for steel and nickel material, and the measured diffraction signals are undetectable when compared to the noise.

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

NASA Astrophysics Data System (ADS)

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

2012-02-01

Detection of illicit materials, such as explosives or drugs, within mixed samples is a major issue, both for general security and as part of forensic analyses. In this paper, we describe a new code simulating energy dispersive X-ray diffraction patterns in polycrystalline materials. This program, SinFullscat, models diffraction of any object in any diffractometer system taking all physical phenomena, including amorphous background, into account. Many system parameters can be tuned: geometry, collimators (slit and cylindrical), sample properties, X-ray source and detector energy resolution. Good agreement between simulations and experimental data was obtained. Simulations using explosive materials indicated that parameters such as the diffraction angle or the energy resolution of the detector have a significant impact on the diffraction signature of the material inspected. This software will be a convenient tool to test many diffractometer configurations, providing information on the one that best restores the spectral diffraction signature of the materials of interest.

Femtosecond X-ray coherent diffraction of aligned amyloid fibrils on low background graphene.

PubMed

Seuring, Carolin; Ayyer, Kartik; Filippaki, Eleftheria; Barthelmess, Miriam; Longchamp, Jean-Nicolas; Ringler, Philippe; Pardini, Tommaso; Wojtas, David H; Coleman, Matthew A; Dörner, Katerina; Fuglerud, Silje; Hammarin, Greger; Habenstein, Birgit; Langkilde, Annette E; Loquet, Antoine; Meents, Alke; Riek, Roland; Stahlberg, Henning; Boutet, Sébastien; Hunter, Mark S; Koglin, Jason; Liang, Mengning; Ginn, Helen M; Millane, Rick P; Frank, Matthias; Barty, Anton; Chapman, Henry N

2018-05-09

Here we present a new approach to diffraction imaging of amyloid fibrils, combining a free-standing graphene support and single nanofocused X-ray pulses of femtosecond duration from an X-ray free-electron laser. Due to the very low background scattering from the graphene support and mutual alignment of filaments, diffraction from tobacco mosaic virus (TMV) filaments and amyloid protofibrils is obtained to 2.7 Å and 2.4 Å resolution in single diffraction patterns, respectively. Some TMV diffraction patterns exhibit asymmetry that indicates the presence of a limited number of axial rotations in the XFEL focus. Signal-to-noise levels from individual diffraction patterns are enhanced using computational alignment and merging, giving patterns that are superior to those obtainable from synchrotron radiation sources. We anticipate that our approach will be a starting point for further investigations into unsolved structures of filaments and other weakly scattering objects.

Diffracted diffraction radiation and its application to beam diagnostics

NASA Astrophysics Data System (ADS)

Goponov, Yu. A.; Shatokhin, R. A.; Sumitani, K.; Syshchenko, V. V.; Takabayashi, Y.; Vnukov, I. E.

2018-03-01

We present theoretical considerations for diffracted diffraction radiation and also propose an application of this process to diagnosing ultra-relativistic electron (positron) beams for the first time. Diffraction radiation is produced when relativistic particles move near a target. If the target is a crystal or X-ray mirror, diffraction radiation in the X-ray region is expected to be diffracted at the Bragg angle and therefore be detectable. We present a scheme for applying this process to measurements of the beam angular spread, and consider how to conduct a proof-of-principle experiment for the proposed method.

Absolute x-ray energy calibration and monitoring using a diffraction-based method

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hong, Xinguo, E-mail: xhong@bnl.gov; Weidner, Donald J.; Duffy, Thomas S.

2016-07-27

In this paper, we report some recent developments of the diffraction-based absolute X-ray energy calibration method. In this calibration method, high spatial resolution of the measured detector offset is essential. To this end, a remotely controlled long-translation motorized stage was employed instead of the less convenient gauge blocks. It is found that the precision of absolute X-ray energy calibration (ΔE/E) is readily achieved down to the level of 10{sup −4} for high-energy monochromatic X-rays (e.g. 80 keV). Examples of applications to pair distribution function (PDF) measurements and energy monitoring for high-energy X-rays are presented.

High-energy cryo x-ray nano-imaging at the ID16A beamline of ESRF

NASA Astrophysics Data System (ADS)

da Silva, Julio C.; Pacureanu, Alexandra; Yang, Yang; Fus, Florin; Hubert, Maxime; Bloch, Leonid; Salome, Murielle; Bohic, Sylvain; Cloetens, Peter

2017-09-01

The ID16A beamline at ESRF offers unique capabilities for X-ray nano-imaging, and currently produces the worlds brightest high energy diffraction-limited nanofocus. Such a nanoprobe was designed for quantitative characterization of the morphology and the elemental composition of specimens at both room and cryogenic temperatures. Billions of photons per second can be delivered in a diffraction-limited focus spot size down to 13 nm. Coherent X-ray imaging techniques, as magnified holographic-tomography and ptychographic-tomography, are implemented as well as X-ray fluorescence nanoscopy. We will show the latest developments in coherent and spectroscopic X-ray nanoimaging implemented at the ID16A beamline

X-ray monitoring optical elements

DOEpatents

Stoupin, Stanislav; Shvydko, Yury; Katsoudas, John; Blank, Vladimir D.; Terentyev, Sergey A.

2016-12-27

An X-ray article and method for analyzing hard X-rays which have interacted with a test system. The X-ray article is operative to diffract or otherwise process X-rays from an input X-ray beam which have interacted with the test system and at the same time provide an electrical circuit adapted to collect photoelectrons emitted from an X-ray optical element of the X-ray article to analyze features of the test system.

Publications - GMC 45 | Alaska Division of Geological & Geophysical Surveys

Science.gov Websites

DGGS GMC 45 Publication Details Title: X-ray diffraction mineral percentages of chips from Exxon Pt , 1983, X-ray diffraction mineral percentages of chips from Exxon Pt. Thomson Unit #1 and #3 wells

Publications - GMC 361 | Alaska Division of Geological & Geophysical

Science.gov Websites

DGGS GMC 361 Publication Details Title: X-ray Diffraction Analysis of: Drew Point #1, East Simpson Test , 2009, X-ray Diffraction Analysis of: Drew Point #1, East Simpson Test Well #1, East Simpson #2

Publications - GMC 41 | Alaska Division of Geological & Geophysical Surveys

Science.gov Websites

DGGS GMC 41 Publication Details Title: X-ray diffraction clay mineralogy analysis of core samples from Unknown, [n.d.], X-ray diffraction clay mineralogy analysis of core samples from Mobil West Staines State

TAKASAGO-6 apparatus for cryogenic coherent X-ray diffraction imaging of biological non-crystalline particles using X-ray free electron laser at SACLA.

PubMed

Kobayashi, Amane; Sekiguchi, Yuki; Takayama, Yuki; Oroguchi, Tomotaka; Shirahama, Keiya; Torizuka, Yasufumi; Manoda, Masahiro; Nakasako, Masayoshi; Yamamoto, Masaki

2016-05-01

Coherent X-ray diffraction imaging (CXDI) is a technique for structure analyses of non-crystalline particles with dimensions ranging from micrometer to sub-micrometer. We have developed a diffraction apparatus named TAKASAGO-6 for use in single-shot CXDI experiments of frozen-hydrated non-crystalline biological particles at cryogenic temperature with X-ray free electron laser pulses provided at a repetition rate of 30 Hz from the SPring-8 Angstrom Compact free-electron LAser. Specimen particles are flash-cooled after being dispersed on thin membranes supported by specially designed disks. The apparatus is equipped with a high-speed translation stage with a cryogenic pot for raster-scanning of the disks at a speed higher than 25 μm/33 ms. In addition, we use devices assisting the easy transfer of cooled specimens from liquid-nitrogen storages to the cryogenic pot. In the current experimental procedure, more than 20 000 diffraction patterns can be collected within 1 h. Here we report the key components and performance of the diffraction apparatus. Based on the efficiency of the diffraction data collection and the structure analyses of metal particles, biological cells, and cellular organelles, we discuss the future application of this diffraction apparatus for structure analyses of biological specimens.

Thermal expansion in UO 2 determined by high-energy X-ray diffraction

DOE PAGES

Guthrie, M.; Benmore, C. J.; Skinner, L. B.; ...

2016-06-24

In this study, we present crystallographic analyses of high-energy X-ray diffraction data on polycrystalline UO 2 up to the melting temperature. The Rietveld refinements of our X-ray data are in agreement with previous measurements, but are systematically located around the upper bound of their uncertainty, indicating a slightly steeper trend of thermal expansion compared to established values. This observation is consistent with recent first principles calculations.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hunter, Mark S.; Yoon, Chun Hong; DeMirci, Hasan

Structural information about biological macromolecules near the atomic scale provides important insight into the functions of these molecules. To date, X-ray crystallography has been the predominant method used for macromolecular structure determination. However, challenges exist when solving structures with X-rays, including the phase problem and radiation damage. X-ray-free electron lasers (X-ray FELs) have enabled collection of diffraction information before the onset of radiation damage, yet the majority of structures solved at X-ray FELs have been phased using external information via molecular replacement. De novo phasing at X-ray FELs has proven challenging due in part to per-pulse variations in intensity andmore » wavelength. Here we report the solution of a selenobiotinyl-streptavidin structure using phases obtained by the anomalous diffraction of selenium measured at a single wavelength (Se-SAD) at the Linac Coherent Light Source. Finally, our results demonstrate Se-SAD, routinely employed at synchrotrons for novel structure determination, is now possible at X-ray FELs.« less

Phase modulation due to crystal diffraction by ptychographic imaging

DOE Office of Scientific and Technical Information (OSTI.GOV)

Civita, M.; Diaz, A.; Bean, R. J.

Solving the phase problem in x-ray crystallography has occupied a considerable scientific effort in the 20th century and led to great advances in structural science. Here we use x-ray ptychography to demonstrate an interference method which measures the phase of the beam transmitted through a crystal, relative to the incoming beam, when diffraction takes place. The observed phase change of the direct beam through a small gold crystal is found to agree with both a quasikinematical model and full dynamical theories of diffraction. Our discovery of a diffraction contrast mechanism will enhance the interpretation of data obtained from crystalline samplesmore » using the ptychography method, which provides some of the most accurate x-ray phase-contrast images.« less

Track membranes with open pores used as diffractive filters for space-based x-ray and EUV solar observations.

PubMed

Dominique, Marie; Mitrofanov, A V; Hochedez, J-F; Apel, P Yu; Schühle, U; Pudonin, F A; Orelovich, O L; Zuev, S Yu; Bolsée, D; Hermans, C; BenMoussa, A

2009-02-10

We describe the fabrication and performance of diffractive filters designed for space-based x-ray and EUV solar observations. Unlike traditional thin film filters, diffractive filters can be made to have a high resistance against the destructive mechanical and acoustic loads of a satellite launch. The filters studied are made of plastic track-etched membranes that are metal-coated on one side only. They have all-through open cylindrical pores with diameters as small as 500 nm, limiting their transmittance to very short wavelengths. The spectral transmittance of various diffractive filters with different pore parameters was measured from the soft x-ray to the near IR range (namely, from 1-1100 nm).

Phase modulation due to crystal diffraction by ptychographic imaging

DOE PAGES

Civita, M.; Diaz, A.; Bean, R. J.; ...

2018-03-06

Solving the phase problem in x-ray crystallography has occupied a considerable scientific effort in the 20th century and led to great advances in structural science. Here we use x-ray ptychography to demonstrate an interference method which measures the phase of the beam transmitted through a crystal, relative to the incoming beam, when diffraction takes place. The observed phase change of the direct beam through a small gold crystal is found to agree with both a quasikinematical model and full dynamical theories of diffraction. Our discovery of a diffraction contrast mechanism will enhance the interpretation of data obtained from crystalline samplesmore » using the ptychography method, which provides some of the most accurate x-ray phase-contrast images.« less

Phase modulation due to crystal diffraction by ptychographic imaging

NASA Astrophysics Data System (ADS)

Civita, M.; Diaz, A.; Bean, R. J.; Shabalin, A. G.; Gorobtsov, O. Yu.; Vartanyants, I. A.; Robinson, I. K.

2018-03-01

Solving the phase problem in x-ray crystallography has occupied a considerable scientific effort in the 20th century and led to great advances in structural science. Here we use x-ray ptychography to demonstrate an interference method which measures the phase of the beam transmitted through a crystal, relative to the incoming beam, when diffraction takes place. The observed phase change of the direct beam through a small gold crystal is found to agree with both a quasikinematical model and full dynamical theories of diffraction. Our discovery of a diffraction contrast mechanism will enhance the interpretation of data obtained from crystalline samples using the ptychography method, which provides some of the most accurate x-ray phase-contrast images.

The Mapping X-Ray Fluorescence Spectrometer (MAPX)

NASA Technical Reports Server (NTRS)

Blake, David; Sarrazin, Philippe; Bristow, Thomas; Downs, Robert; Gailhanou, Marc; Marchis, Franck; Ming, Douglas; Morris, Richard; Sole, Vincente Armando; Thompson, Kathleen;

Nanomodulated electron beams via electron diffraction and emittance exchange for coherent x-ray generation

DOE PAGES

Nanni, E. A.; Graves, W. S.; Moncton, D. E.

2018-01-19

We present a new method for generation of relativistic electron beams with current modulation on the nanometer scale and below. The current modulation is produced by diffracting relativistic electrons in single crystal Si, accelerating the diffracted beam and imaging the crystal structure, then transferring the image into the temporal dimension via emittance exchange. The modulation period can be tuned by adjusting electron optics after diffraction. This tunable longitudinal modulation can have a period as short as a few angstroms, enabling production of coherent hard x-rays from a source based on inverse Compton scattering with total accelerator length of approximately tenmore » meters. Electron beam simulations from cathode emission through diffraction, acceleration, and image formation with variable magnification are presented along with estimates of the coherent x-ray output properties.« less

Nanomodulated electron beams via electron diffraction and emittance exchange for coherent x-ray generation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nanni, E. A.; Graves, W. S.; Moncton, D. E.

We present a new method for generation of relativistic electron beams with current modulation on the nanometer scale and below. The current modulation is produced by diffracting relativistic electrons in single crystal Si, accelerating the diffracted beam and imaging the crystal structure, then transferring the image into the temporal dimension via emittance exchange. The modulation period can be tuned by adjusting electron optics after diffraction. This tunable longitudinal modulation can have a period as short as a few angstroms, enabling production of coherent hard x-rays from a source based on inverse Compton scattering with total accelerator length of approximately tenmore » meters. Electron beam simulations from cathode emission through diffraction, acceleration, and image formation with variable magnification are presented along with estimates of the coherent x-ray output properties.« less

Coherent diffraction imaging analysis of shape-controlled nanoparticles with focused hard X-ray free-electron laser pulses.

PubMed

Takahashi, Yukio; Suzuki, Akihiro; Zettsu, Nobuyuki; Oroguchi, Tomotaka; Takayama, Yuki; Sekiguchi, Yuki; Kobayashi, Amane; Yamamoto, Masaki; Nakasako, Masayoshi

2013-01-01

We report the first demonstration of the coherent diffraction imaging analysis of nanoparticles using focused hard X-ray free-electron laser pulses, allowing us to analyze the size distribution of particles as well as the electron density projection of individual particles. We measured 1000 single-shot coherent X-ray diffraction patterns of shape-controlled Ag nanocubes and Au/Ag nanoboxes and estimated the edge length from the speckle size of the coherent diffraction patterns. We then reconstructed the two-dimensional electron density projection with sub-10 nm resolution from selected coherent diffraction patterns. This method enables the simultaneous analysis of the size distribution of synthesized nanoparticles and the structures of particles at nanoscale resolution to address correlations between individual structures of components and the statistical properties in heterogeneous systems such as nanoparticles and cells.

Cryogenic X-Ray Diffraction Microscopy for Biological Samples

NASA Astrophysics Data System (ADS)

Lima, Enju; Wiegart, Lutz; Pernot, Petra; Howells, Malcolm; Timmins, Joanna; Zontone, Federico; Madsen, Anders

2009-11-01

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

Single-pulse coherent diffraction imaging using soft x-ray laser.

PubMed

Kang, Hyon Chol; Kim, Hyung Taek; Kim, Sang Soo; Kim, Chan; Yu, Tae Jun; Lee, Seong Ku; Kim, Chul Min; Kim, I Jong; Sung, Jae Hee; Janulewicz, Karol A; Lee, Jongmin; Noh, Do Young

2012-05-15

We report a coherent diffraction imaging (CDI) using a single 8 ps soft x-ray laser pulse at a wavelength of 13.9 nm. The soft x-ray pulse was generated by a laboratory-scale intense pumping laser providing coherent x-ray pulses up to the level of 10(11) photons/pulse. A spatial resolution below 194 nm was achieved with a single pulse, and it was shown that a resolution below 55 nm is feasible with improved detector capability. The single-pulse CDI might provide a way to investigate dynamics of nanoscale molecules or particles.

Surface Relaxation in Protein Crystals

NASA Technical Reports Server (NTRS)

Boutet, S.; Robinson, I. K.; Hu, Z. W.; Thomas, B. R.; Chernov, A. A.

2002-01-01

Surface X-ray diffraction measurements were performed on (111) growth faces of crystals of the Cellular iron-storage protein horse spleen ferritin. Crystal Trunkation Rods (CTR) were measured. A fit of the measured profile of the CTR revealed a surface roughness of 48 +/- 4.5 A and a top layer spacing contraction of 3.9 +/- 1.5%. In addition to the peak from the CTR, the rocking curves of the crystals displayed unexpected extra peaks. Multiple-scattering is demonstrated to account for them. Future applications of the method could allow the exploration of hydration effects on the growth of protein crystals.

Hydride vapor phase epitaxy of AlN using a high temperature hot-wall reactor

NASA Astrophysics Data System (ADS)

Baker, Troy; Mayo, Ashley; Veisi, Zeinab; Lu, Peng; Schmitt, Jason

2014-10-01

Aluminum nitride (AlN) was grown on c-plane sapphire substrates by hydride vapor phase epitaxy (HVPE). The experiments utilized a two zone inductively heated hot-wall reactor. The surface morphology, crystal quality, and growth rate were investigated as a function of growth temperature in the range of 1450-1575 °C. AlN templates grown to a thickness of 1 μm were optimized with double axis X-ray diffraction (XRD) rocking curve full width half maximums (FWHMs) of 135″ for the (002) and 513″ for the (102).

In situ crystal chemical study of solid diamond inclusions from Quaternary alluvial deposit in the Siberian craton

NASA Astrophysics Data System (ADS)

Dera, P. K.; Manghnani, M. H.; Hushur, A.; Sobolev, N. V.; Logvinova, A. M.; Newville, M.; Lanzirotti, A.

2013-12-01

Kimberlites belong to rare rock type available only within the Earth's cratonic areas and have been a subject of detailed studies because of the great depth of their origin in the mantle. Kimberlitic diamonds often contain pristine inclusions derived from significant depths with different histories of their origins. Many of kimberlitic diamonds were formed in ultramafic (peridotitic) and mafic (eclogitic) environments of the upper mantle. Thus far only a handful of comprehensive in situ studies including single-crystal X-ray diffraction characterization of pristine diamond solid inclusions have been reported (e.g. Kunz et al. 2001, Nestola et al. 2011). In this study five single-crystal solid inclusions from diamonds found in the Quaternary alluvial deposit in NW of the Siberian craton have been investigated using a combination of in situ single-crystal X-ray diffraction, Raman spectroscopy, synchrotron X-ray microfluorescence and X-ray Absorption Near Edge Spectroscopy (XANES). The grains were identified to be a suite of major upper mantle minerals including olivine, enstatite orthopyroxene (opx), C2/c omphacite clinopyroxene (cpx) and majoritic garnet (two grains), indicating eclogitic origin. All five inclusions are chemically homogeneous, do not show compositional zoning, and exhibit very similar major element chemistry, with significant amounts of Mn2+, Ni2+ and Cr3+ incorporated into the crystal structures, suggesting common geologic origin. All samples were studied in situ, while still embedded in the diamond crystals. High quality single-crystal X-ray diffraction data was collected at the Advanced Photon Source, Argonne National Laboratory to reveal details of the crystal structures and provide crystal chemical information. Some of the structural characteristics of the solid inclusions were found to be fairly uncommon, e.g. the orthoenstatite exhibits an unusually high Ca2+ content (Carlson et al. 1988), and omphacite occurs as the less common C2/c polymorph (Banno, 1970), both of which are considered signatures of eclogitic high-temperature facies. Fe Ka-edge XANES was used to investigate the oxidation state of iron in the solid inclusions. All of the inclusions show predominantly Fe2+, indicating reducing conditions of formation. The combined results of our spectroscopic and diffraction experiments will be interpreted in the context of the conditions and mechanism of formation (syngenesis vs. protogenesis) and possible retrograde transformation the inclusions may have experienced when transported to the surface. References Carlson, W.D. J.S. Swinnea, D.E. Miser (1988) 'Stability of orthoenstatite at high temperature and low pressure' Amer. Mineral. 73: 1255-1263. Banno, S. (1970) 'Classification of eclogites in terms of physical condition of their origin' Phys. Earth. Planet. Interiors 3: 405-421. Kunz, M., P. Gillet, et al. (2002). "Combined in situ X-ray diffraction and Raman spectroscopy on majoritic garnet inclusions in diamonds." Earth and Planet. Sci. Lett. 198: 485-493. Nestola, F., P. Nimis, et al. (2011). "First crystal-structure determination of olivine in diamond: Composition and implications for provenance in the Earth's mantle." Earth and Planet. Sci. Lett. 305: 249-255.

Curiosity Rover's CheMin Instrument Investigates Mineralogy of Gale Crater and Implications for Diagenesis

NASA Astrophysics Data System (ADS)

Fendrich, Kim; Rampe, Elizabeth; Vaniman, David; Bish, David; Blake, David; Treiman, Allan; Ming, Doug; Morris, Richard; Bristow, Tom; Cavanagh, Patrick; Downs, Robert; Morrison, Shaunna; Chipera, Steve; Achilles, Cherie; Farmer, Jack; Sarrazin, Philippe; Crisp, Joy; Morookian, John Michael; Yen, Albert; Gellert, Ralf

2015-04-01

The Mars Science Laboratory rover Curiosity employs a suite of instruments to investigate past or present habitability of Mars, as observed at Gale crater and particularly in the lower strata of the crater's central mound, informally named Mount Sharp. The X-ray diffractometer on board, CheMin, is used to assess the quantitative mineralogy of scooped soil samples and drilled rock powders. Methods of modeling diffraction peak positions and intensities to evaluate the abundances of minerals include Rietveld refinement and FULLPAT (full-pattern fitting). Each of the samples analyzed by CheMin contains X-ray amorphous material. The amorphous component chemistry is resolved by subtracting the chemistry of the crystalline composition, as determined by X-ray diffraction data, from the bulk sample chemistry, as determined by the Alpha Particle X-ray Spectrometer (APXS). Diffraction results have been obtained on five samples thus far to include Rocknest, John Klein, Cumberland, Windjana and Confidence Hills. Soil samples collected at Rocknest, an aeolian bedform in Gale crater, were the first to be analyzed in situ by CheMin. The Rocknest mineral assemblage is basaltic (plagioclase, Fe-forsterite, augite, pigeonite) and contains amorphous material that is compositionally similar to palagonitic volcanic soils found on Earth, with the addition of sulfur and chlorine. The four drill analyses are characteristic of deposition in a variety of fluvio-lacustrine environments and exhibit evidence of low-temperature diagenesis. Both John Klein and Cumberland are part of the Sheepbed mudstone at Yellowknife Bay, where the first drilled samples were acquired as well as the first evidence of a habitable environment on Mars. Drilled three meters apart from each other, the two samples reveal basaltic minerals similar to those at Rocknest, as well as phyllosilicates, Fe-oxides/hydroxides, Ca-sulfates, Fe-sulfides, and amorphous materials. The nature and hydration of interlayer cations within the phyllosilicates differs between the two samples, which implies localized diagenesis. The Windjana sandstone at the Kimberley location differs from the Sheepbed mudstone in that it contains more pyroxene and magnetite and abundant K-feldspar, as well as phyllosilicates and amorphous material. These phases may represent potassium-rich basaltic provenance or aqueous alteration by potassium-bearing fluids. While the Confidence Hills sample is still in the preliminary stages of evaluation, major crystalline phases observed in this fine-grained sedimentary rock include plagioclase, pyroxene, K-feldspar and phyllosilicates; hematite, rare in all previous samples, is notably abundant and jarosite is present. The findings suggest localized mobilization of iron-bearing fluids and acidic conditions. The more oxidized assemblage of Confidence Hills marks the transition into the lower strata of Mount Sharp.

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

NASA Astrophysics Data System (ADS)

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

2010-10-01

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

Electronic and atomic structures of Ti{sub 1-x}Al{sub x}N thin films related to their damage behavior

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tuilier, M.-H.; Pac, M.-J.; Girleanu, M.

2008-04-15

Ti and Al K-edge x-ray absorption spectroscopy is used to investigate the electronic structure of Ti{sub 1-x}Al{sub x}N thin films deposited by reactive magnetron sputtering. The experimental near edge spectra of TiN and AlN are interpreted in the light of unoccupied density of state band structure calculations. The comparison of the structural parameters derived from x-ray absorption fine structure and x-ray diffraction reveals segregation between Al-rich and Ti-rich domains within the Ti{sub 1-x}Al{sub x}N films. Whereas x-ray diffraction probes only the crystallized domains, the structural information derived from extended x-ray absorption fine structure analysis turns on both crystalline and grainmore » boundaries. The results are discussed by considering the damage behavior of the films depending on the composition.« less

Structure of rare-earth chalcogenide glasses by neutron and x-ray diffraction

DOE Office of Scientific and Technical Information (OSTI.GOV)

Drewitt, James W. E.; Salmon, Philip S.; Zeidler, Anita

The method of neutron diffraction with isomorphic substitution was used to measure the structure of the rare-earth chalcogenide glasses (R 2X 3) 0.07(Ga 2X 3) 0.33(GeX 2) 0.60 with R = La or Ce and X = S or Se. X-ray diffraction was also used to measure the structure of the sulphide glass. The results are consistent with networks that are built from GeX 4 and GaX 4 tetrahedra, and give R-S and R-Se coordination numbers of 8.0(2) and 8.5(4), respectively. The minimum nearest-neighbour R-R distance associated with rare-earth clustering is discussed.

Structure of rare-earth chalcogenide glasses by neutron and x-ray diffraction

DOE PAGES

Drewitt, James W. E.; Salmon, Philip S.; Zeidler, Anita; ...

2017-04-28

The method of neutron diffraction with isomorphic substitution was used to measure the structure of the rare-earth chalcogenide glasses (R 2X 3) 0.07(Ga 2X 3) 0.33(GeX 2) 0.60 with R = La or Ce and X = S or Se. X-ray diffraction was also used to measure the structure of the sulphide glass. The results are consistent with networks that are built from GeX 4 and GaX 4 tetrahedra, and give R-S and R-Se coordination numbers of 8.0(2) and 8.5(4), respectively. The minimum nearest-neighbour R-R distance associated with rare-earth clustering is discussed.

Publications - GMC 145 | Alaska Division of Geological & Geophysical

Science.gov Websites

DGGS GMC 145 Publication Details Title: Analytical results of x-ray diffraction studies on tuff beds , Analytical results of x-ray diffraction studies on tuff beds from core of the following 5 NPRA wells: U.S

Coherent Soft X-ray Diffraction Imaging of Coliphage PR772 at the Linac Coherent Light Source

DOE Data Explorer

Reddy, Hemanth, K.N.

2017-01-05

A dataset of coherent soft X-ray diffraction images of Coliphage PR772 virus, collected at the Atomic Molecular Optics (AMO) beamline with pnCCD detectors in the LAMP instrument at the Linac Coherent Light Source.

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

PubMed

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

2013-06-01

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

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

PubMed

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.

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

DOE PAGES

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

2016-08-09

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

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

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

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

A laboratory based system for laue micro x-ray diffraction.

PubMed

Lynch, P A; Stevenson, A W; Liang, D; Parry, D; Wilkins, S; Tamura, N

2007-02-01

A laboratory diffraction system capable of illuminating individual grains in a polycrystalline matrix is described. Using a microfocus x-ray source equipped with a tungsten anode and prefigured monocapillary optic, a micro-x-ray diffraction system with a 10 microm beam was developed. The beam profile generated by the ellipsoidal capillary was determined using the "knife edge" approach. Measurement of the capillary performance, indicated a beam divergence of 14 mrad and a useable energy bandpass from 5.5 to 19 keV. Utilizing the polychromatic nature of the incident x-ray beam and application of the Laue indexing software package X-Ray Micro-Diffraction Analysis Software, the orientation and deviatoric strain of single grains in a polycrystalline material can be studied. To highlight the system potential the grain orientation and strain distribution of individual grains in a polycrystalline magnesium alloy (Mg 0.2 wt % Nd) was mapped before and after tensile loading. A basal (0002) orientation was identified in the as-rolled annealed alloy; after tensile loading some grains were observed to undergo an orientation change of 30 degrees with respect to (0002). The applied uniaxial load was measured as an increase in the deviatoric tensile strain parallel to the load axis.

Visualization of membrane protein crystals in lipid cubic phase using X-ray imaging

PubMed Central

Warren, Anna J.; Armour, Wes; Axford, Danny; Basham, Mark; Connolley, Thomas; Hall, David R.; Horrell, Sam; McAuley, Katherine E.; Mykhaylyk, Vitaliy; Wagner, Armin; Evans, Gwyndaf

2013-01-01

The focus in macromolecular crystallography is moving towards even more challenging target proteins that often crystallize on much smaller scales and are frequently mounted in opaque or highly refractive materials. It is therefore essential that X-ray beamline technology develops in parallel to accommodate such difficult samples. In this paper, the use of X-ray microradiography and microtomography is reported as a tool for crystal visualization, location and characterization on the macromolecular crystallography beamlines at the Diamond Light Source. The technique is particularly useful for microcrystals and for crystals mounted in opaque materials such as lipid cubic phase. X-ray diffraction raster scanning can be used in combination with radiography to allow informed decision-making at the beamline prior to diffraction data collection. It is demonstrated that the X-ray dose required for a full tomography measurement is similar to that for a diffraction grid-scan, but for sample location and shape estimation alone just a few radiographic projections may be required. PMID:23793151

Visualization of membrane protein crystals in lipid cubic phase using X-ray imaging.

PubMed

Warren, Anna J; Armour, Wes; Axford, Danny; Basham, Mark; Connolley, Thomas; Hall, David R; Horrell, Sam; McAuley, Katherine E; Mykhaylyk, Vitaliy; Wagner, Armin; Evans, Gwyndaf

2013-07-01

The focus in macromolecular crystallography is moving towards even more challenging target proteins that often crystallize on much smaller scales and are frequently mounted in opaque or highly refractive materials. It is therefore essential that X-ray beamline technology develops in parallel to accommodate such difficult samples. In this paper, the use of X-ray microradiography and microtomography is reported as a tool for crystal visualization, location and characterization on the macromolecular crystallography beamlines at the Diamond Light Source. The technique is particularly useful for microcrystals and for crystals mounted in opaque materials such as lipid cubic phase. X-ray diffraction raster scanning can be used in combination with radiography to allow informed decision-making at the beamline prior to diffraction data collection. It is demonstrated that the X-ray dose required for a full tomography measurement is similar to that for a diffraction grid-scan, but for sample location and shape estimation alone just a few radiographic projections may be required.

Monochromatic X-ray sources based on a mechanism of real and virtual photon diffraction in crystals

NASA Astrophysics Data System (ADS)

Wagner, A. R.; Kuznetsov, S. I.; Potylitsyn, A. P.; Razin, S. V.; Uglov, S. R.; Zabaev, V. N.

2008-09-01

A source of monochromatic X-ray radiation is wanted in industry, science, medicine and so on. Many ways of making such a source are known. The present work describes two mechanisms for the creation of a monochromatic X-ray beam, which are parametric X-ray radiation (PXR) and bremsstrahlung diffraction (DBS). Both the experiments were carried out using an electron beam at a microtron. During the first experiment, the DBS process was investigated as a scattering of the Bremsstrahlung (BS) beam on the crystallographic surfaces of tungsten and pyrolytic graphite crystals. The second experiment consisted in the registration of the PXR and DBS yield during the passage of the electrons through the same crystals as in the first experiment. The spectral and orientation radiation characteristics and simulation results obtained for the DBS and PXR processes are presented. It is shown that the usage of mosaic crystalline targets is rather useful in order to obtain a monochromatic X-ray source based on bremsstrahlung diffraction from moderately relativistic electrons.

Insights into photosystem II from isomorphous difference Fourier maps of femtosecond X-ray diffraction data and quantum mechanics/molecular mechanics structural models

DOE PAGES

Wang, Jimin; Askerka, Mikhail; Brudvig, Gary W.; ...

2017-01-12

Understanding structure–function relations in photosystem II (PSII) is important for the development of biomimetic photocatalytic systems. X-ray crystallography, computational modeling, and spectroscopy have played central roles in elucidating the structure and function of PSII. Recent breakthroughs in femtosecond X-ray crystallography offer the possibility of collecting diffraction data from the X-ray free electron laser (XFEL) before radiation damage of the sample, thereby overcoming the main challenge of conventional X-ray diffraction methods. However, the interpretation of XFEL data from PSII intermediates is challenging because of the issues regarding data-processing, uncertainty on the precise positions of light oxygen atoms next to heavy metalmore » centers, and different kinetics of the S-state transition in microcrystals compared to solution. Lastly, we summarize recent advances and outstanding challenges in PSII structure–function determination with emphasis on the implementation of quantum mechanics/molecular mechanics techniques combined with isomorphous difference Fourier maps, direct methods, and high-resolution spectroscopy.« less

Single-shot full strain tensor determination with microbeam X-ray Laue diffraction and a two-dimensional energy-dispersive detector.

PubMed

Abboud, A; Kirchlechner, C; Keckes, J; Conka Nurdan, T; Send, S; Micha, J S; Ulrich, O; Hartmann, R; Strüder, L; Pietsch, U

2017-06-01

The full strain and stress tensor determination in a triaxially stressed single crystal using X-ray diffraction requires a series of lattice spacing measurements at different crystal orientations. This can be achieved using a tunable X-ray source. This article reports on a novel experimental procedure for single-shot full strain tensor determination using polychromatic synchrotron radiation with an energy range from 5 to 23 keV. Microbeam X-ray Laue diffraction patterns were collected from a copper micro-bending beam along the central axis (centroid of the cross section). Taking advantage of a two-dimensional energy-dispersive X-ray detector (pnCCD), the position and energy of the collected Laue spots were measured for multiple positions on the sample, allowing the measurement of variations in the local microstructure. At the same time, both the deviatoric and hydrostatic components of the elastic strain and stress tensors were calculated.

Demonstration of the feasibility of an integrated x ray laboratory for planetary exploration

NASA Technical Reports Server (NTRS)

Franco, E. D.; Kerner, J. A.; Koppel, L. N.; Boyle, M. J.

1993-01-01

The identification of minerals and elemental compositions is an important component in the geological and exobiological exploration of the solar system. X ray diffraction and fluorescence are common techniques for obtaining these data. The feasibility of combining these analytical techniques in an integrated x ray laboratory compatible with the volume, mass, and power constraints imposed by many planetary missions was demonstrated. Breadboard level hardware was developed to cover the range of diffraction lines produced by minerals, clays, and amorphous; and to detect the x ray fluorescence emissions of elements from carbon through uranium. These breadboard modules were fabricated and used to demonstrate the ability to detect elements and minerals. Additional effort is required to establish the detection limits of the breadboard modules and to integrate diffraction and fluorescence techniques into a single unit. It was concluded that this integrated x ray laboratory capability will be a valuable tool in the geological and exobiological exploration of the solar system.

Insights into Photosystem II from Isomorphous Difference Fourier Maps of Femtosecond X-ray Diffraction Data and Quantum Mechanics/Molecular Mechanics Structural Models.

PubMed

Wang, Jimin; Askerka, Mikhail; Brudvig, Gary W; Batista, Victor S

2017-02-10

Understanding structure-function relations in photosystem II (PSII) is important for the development of biomimetic photocatalytic systems. X-ray crystallography, computational modeling, and spectroscopy have played central roles in elucidating the structure and function of PSII. Recent breakthroughs in femtosecond X-ray crystallography offer the possibility of collecting diffraction data from the X-ray free electron laser (XFEL) before radiation damage of the sample, thereby overcoming the main challenge of conventional X-ray diffraction methods. However, the interpretation of XFEL data from PSII intermediates is challenging because of the issues regarding data-processing, uncertainty on the precise positions of light oxygen atoms next to heavy metal centers, and different kinetics of the S-state transition in microcrystals compared to solution. Here, we summarize recent advances and outstanding challenges in PSII structure-function determination with emphasis on the implementation of quantum mechanics/molecular mechanics techniques combined with isomorphous difference Fourier maps, direct methods, and high-resolution spectroscopy.

Insights into photosystem II from isomorphous difference Fourier maps of femtosecond X-ray diffraction data and quantum mechanics/molecular mechanics structural models

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Jimin; Askerka, Mikhail; Brudvig, Gary W.

Understanding structure–function relations in photosystem II (PSII) is important for the development of biomimetic photocatalytic systems. X-ray crystallography, computational modeling, and spectroscopy have played central roles in elucidating the structure and function of PSII. Recent breakthroughs in femtosecond X-ray crystallography offer the possibility of collecting diffraction data from the X-ray free electron laser (XFEL) before radiation damage of the sample, thereby overcoming the main challenge of conventional X-ray diffraction methods. However, the interpretation of XFEL data from PSII intermediates is challenging because of the issues regarding data-processing, uncertainty on the precise positions of light oxygen atoms next to heavy metalmore » centers, and different kinetics of the S-state transition in microcrystals compared to solution. Lastly, we summarize recent advances and outstanding challenges in PSII structure–function determination with emphasis on the implementation of quantum mechanics/molecular mechanics techniques combined with isomorphous difference Fourier maps, direct methods, and high-resolution spectroscopy.« less

Nondestructive method and apparatus for imaging grains in curved surfaces of polycrystalline articles

DOEpatents

Carpenter, Donald A.

1995-01-01

A nondestructive method, and associated apparatus, are provided for determining the grain flow of the grains in a convex curved, textured polycrystalline surface. The convex, curved surface of a polycrystalline article is aligned in a horizontal x-ray diffractometer and a monochromatic, converging x-ray beam is directed onto the curved surface of the polycrystalline article so that the converging x-ray beam is diffracted by crystallographic planes of the grains in the polycrystalline article. The diffracted x-ray beam is caused to pass through a set of horizontal, parallel slits to limit the height of the beam and thereafter. The linear intensity of the diffracted x-ray is measured, using a linear position sensitive proportional counter, as a function of position in a direction orthogonal to the counter so as to generate two dimensional data. An image of the grains in the curved surface of the polycrystalline article is provided based on the two-dimensional data.

Nondestructive method and apparatus for imaging grains in curved surfaces of polycrystalline articles

DOEpatents

Carpenter, D.A.

1995-05-23

A nondestructive method, and associated apparatus, are provided for determining the grain flow of the grains in a convex curved, textured polycrystalline surface. The convex, curved surface of a polycrystalline article is aligned in a horizontal x-ray diffractometer and a monochromatic, converging x-ray beam is directed onto the curved surface of the polycrystalline article so that the converging x-ray beam is diffracted by crystallographic planes of the grains in the polycrystalline article. The diffracted x-ray beam is caused to pass through a set of horizontal, parallel slits to limit the height of the beam and thereafter. The linear intensity of the diffracted x-ray is measured, using a linear position sensitive proportional counter, as a function of position in a direction orthogonal to the counter so as to generate two dimensional data. An image of the grains in the curved surface of the polycrystalline article is provided based on the two-dimensional data. 7 Figs.

Observation of femtosecond X-ray interactions with matter using an X-ray–X-ray pump–probe scheme

PubMed Central

Inoue, Ichiro; Inubushi, Yuichi; Sato, Takahiro; Tono, Kensuke; Katayama, Tetsuo; Kameshima, Takashi; Ogawa, Kanade; Togashi, Tadashi; Owada, Shigeki; Amemiya, Yoshiyuki; Tanaka, Takashi; Hara, Toru

2016-01-01

Resolution in the X-ray structure determination of noncrystalline samples has been limited to several tens of nanometers, because deep X-ray irradiation required for enhanced resolution causes radiation damage to samples. However, theoretical studies predict that the femtosecond (fs) durations of X-ray free-electron laser (XFEL) pulses make it possible to record scattering signals before the initiation of X-ray damage processes; thus, an ultraintense X-ray beam can be used beyond the conventional limit of radiation dose. Here, we verify this scenario by directly observing femtosecond X-ray damage processes in diamond irradiated with extraordinarily intense (∼1019 W/cm2) XFEL pulses. An X-ray pump–probe diffraction scheme was developed in this study; tightly focused double–5-fs XFEL pulses with time separations ranging from sub-fs to 80 fs were used to excite (i.e., pump) the diamond and characterize (i.e., probe) the temporal changes of the crystalline structures through Bragg reflection. It was found that the pump and probe diffraction intensities remain almost constant for shorter time separations of the double pulse, whereas the probe diffraction intensities decreased after 20 fs following pump pulse irradiation due to the X-ray–induced atomic displacement. This result indicates that sub-10-fs XFEL pulses enable conductions of damageless structural determinations and supports the validity of the theoretical predictions of ultraintense X-ray–matter interactions. The X-ray pump–probe scheme demonstrated here would be effective for understanding ultraintense X-ray–matter interactions, which will greatly stimulate advanced XFEL applications, such as atomic structure determination of a single molecule and generation of exotic matters with high energy densities. PMID:26811449

The new Athena alpha particle X-ray spectrometer for the Mars Exploration Rovers

NASA Astrophysics Data System (ADS)

Rieder, R.; Gellert, R.; Brückner, J.; Klingelhöfer, G.; Dreibus, G.; Yen, A.; Squyres, S. W.

2003-11-01

The new alpha particle X-ray spectrometer (APXS) is part of the Athena payload of the two Mars Exploration Rovers (MER). The APXS sensor head is attached to the turret of the instrument deployment device (IDD) of the rover. The APXS is a very light-weight instrument for determining the major and minor elemental composition of Martian soils, rocks, and other geological materials at the MER landing sites. The sensor head has simply to be docked by the IDD on the surface of the selected sample. X-ray radiation, excited by alpha particles and X rays of the radioactive sources, is recorded by a high-resolution X-ray detector. The X-ray spectra show elements starting from sodium up to yttrium, depending on their concentrations. The backscattered alpha spectra, measured by a ring of detectors, provide additional data on carbon and oxygen. By means of a proper calibration, the elemental concentrations are derived. Together with data from the two other Athena instruments mounted on the IDD, the samples under investigation can be fully characterized. Key APXS objectives are the determination of the chemistry of crustal rocks and soils and the examination of water-related deposits, sediments, or evaporates. Using the rock abrasion tool attached to the IDD, issues of weathering can be addressed by measuring natural and abraded surfaces of rocks.

Fine Structure of Diffuse Scattering Rings in Al-Li-Cu Quasicrystal: A Comparative X-ray and Electron Diffraction Study

NASA Astrophysics Data System (ADS)

Donnadieu, P.; Dénoyer, F.

1996-11-01

A comparative X-ray and electron diffraction study has been performed on Al-Li-Cu icosahedral quasicrystal in order to investigate the diffuse scattering rings revealed by a previous work. Electron diffraction confirms the existence of rings but shows that the rings have a fine structure. The diffuse aspect on the X-ray diffraction patterns is then due to an averaging effect. Recent simulations based on the model of canonical cells related to the icosahedral packing give diffractions patterns in agreement with this fine structure effect. Nous comparons les diagrammes de diffraction des rayon-X et des électrons obtenus sur les mêmes échantillons du quasicristal icosaèdrique Al-Li-Cu. Notre but est d'étudier les anneaux de diffusion diffuse mis en évidence par un travail précédent. Les diagrammes de diffraction électronique confirment la présence des anneaux mais ils montrent aussi que ces anneaux possèdent une structure fine. L'aspect diffus des anneaux révélés par la diffraction des rayons X est dû à un effet de moyenne. Des simulations récentes basées sur la décomposition en cellules canoniques de l'empilement icosaédrique produisent des diagrammes de diffraction en accord avec ces effects de structure fine.

Effect of Ar9+ irradiation on Zr-1Nb-1Sn-0.1Fe alloy characterized by Grazing Incidence X-ray diffraction technique

NASA Astrophysics Data System (ADS)

Dutta, Argha; Das, Kalipada; Gayathri, N.; Menon, Ranjini; Nabhiraj, P. Y.; Mukherjee, Paramita

2018-03-01

The microstructural parameters such as domain size and microstrain have been estimated from Grazing Incidence X-ray Diffraction (GIXRD) data for Ar9+ irradiated Zr-1Nb-1Sn-0.1Fe sample as a function of dpa (dose). Detail studies using X-ray Diffraction Line Profile Analysis (XRDLPA) from GIXRD data has been carried out to characterize the microstructural parameters like domain size and microstrain. The reorientation of the grains due to effect of irradiation at high dpa (dose) has been qualitatively assessed by the texture parameter P(hkl).

Biological imaging by soft x-ray diffraction microscopy

DOE PAGES

Shapiro, D.; Thibault, P.; Beetz, T.; ...

2005-10-25

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

X-ray diffraction study of laser-driven solid-state diffusional mixing and new phase formation in Ni-Pt multilayers [X-ray diffraction study of laser-driven solid-state diffusional mixing and new phase formation

DOE PAGES

Kelly, B. G.; Loether, A.; Unruh, K. M.; ...

2017-02-01

An in situ optical pump and x-ray probe technique has been utilized to study photoinitiated solid-state diffusion in a Ni-Pt multilayer system. Hard x-ray diffraction has been used to follow the systematic growth of the NiPt alloy as a function of laser intensity and total energy deposited. It is observed that new phase growth can be driven in as little as one laser pulse, and that repeated photoexcitation can completely convert the entire multilayer structure into a single metallic alloy. In conclusion, the data suggest that lattice strain relaxation takes place prior to atomic diffusion and the formation of amore » NiPt alloy.« less

X-ray diffraction study of laser-driven solid-state diffusional mixing and new phase formation in Ni-Pt multilayers [X-ray diffraction study of laser-driven solid-state diffusional mixing and new phase formation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kelly, B. G.; Loether, A.; Unruh, K. M.

An in situ optical pump and x-ray probe technique has been utilized to study photoinitiated solid-state diffusion in a Ni-Pt multilayer system. Hard x-ray diffraction has been used to follow the systematic growth of the NiPt alloy as a function of laser intensity and total energy deposited. It is observed that new phase growth can be driven in as little as one laser pulse, and that repeated photoexcitation can completely convert the entire multilayer structure into a single metallic alloy. In conclusion, the data suggest that lattice strain relaxation takes place prior to atomic diffusion and the formation of amore » NiPt alloy.« less

Spread spectrum phase modulation for coherent X-ray diffraction imaging.

PubMed

Zhang, Xuesong; Jiang, Jing; Xiangli, Bin; Arce, Gonzalo R

2015-09-21

High dynamic range, phase ambiguity and radiation limited resolution are three challenging issues in coherent X-ray diffraction imaging (CXDI), which limit the achievable imaging resolution. This paper proposes a spread spectrum phase modulation (SSPM) method to address the aforementioned problems in a single strobe. The requirements on phase modulator parameters are presented, and a practical implementation of SSPM is discussed via ray optics analysis. Numerical experiments demonstrate the performance of SSPM under the constraint of available X-ray optics fabrication accuracy, showing its potential to real CXDI applications.

Nanofiber-Based Bulk-Heterojunction Organic Solar Cells Using Coaxial Electrospinning

DTIC Science & Technology

2012-01-01

chains are likely oriented with the [010] direction, perpendicular to the substrate, in the fi lm device. Glancing incidence X - ray diffraction (GIXD...Electron and X - ray diffraction measurements were per- formed in order to study the structural order in annealed fi bers and devices. For reference... angle X - ray scattering (SAXS/WAXS) beamline 7.3.3 of the Advanced Light Source at Lawrence Berkeley National Laboratory at 10 keV (1.24 Å) from a bend

Three-dimensional x-ray diffraction nanoscopy

NASA Astrophysics Data System (ADS)

Nikulin, Andrei Y.; Dilanian, Ruben A.; Zatsepin, Nadia A.; Muddle, Barry C.

2008-08-01

A novel approach to x-ray diffraction data analysis for non-destructive determination of the shape of nanoscale particles and clusters in three-dimensions is illustrated with representative examples of composite nanostructures. The technique is insensitive to the x-rays coherence, which allows 3D reconstruction of a modal image without tomographic synthesis and in-situ analysis of large (over a several cubic millimeters) volume of material with a spatial resolution of few nanometers, rendering the approach suitable for laboratory facilities.

A Compact X-Ray System for Support of High Throughput Crystallography

NASA Technical Reports Server (NTRS)

Ciszak, Ewa; Gubarev, Mikhail; Gibson, Walter M.; Joy, Marshall K.; Whitaker, Ann F. (Technical Monitor)

2001-01-01

Standard x-ray systems for crystallography rely on massive generators coupled with optics that guide X-ray beams onto the crystal sample. Optics for single-crystal diffractometry include total reflection mirrors, polycapillary optics or graded multilayer monochromators. The benefit of using polycapillary optic is that it can collect x-rays over tile greatest solid angle, and thus most efficiently, utilize the greatest portion of X-rays emitted from the Source, The x-ray generator has to have a small anode spot, and thus its size and power requirements can be substantially reduced We present the design and results from the first high flux x-ray system for crystallography that combine's a microfocus X-ray generator (40microns FWHM Spot size at a power of 45 W) and a collimating, polycapillary optic. Diffraction data collected from small test crystals with cell dimensions up to 160A (lysozyme and thaumatin) are of high quality. For example, diffraction data collected from a lysozyme crystal at RT yielded R=5.0% for data extending to 1.70A. We compare these results with measurements taken from standard crystallographic systems. Our current microfocus X-ray diffraction system is attractive for supporting crystal growth research in the standard crystallography laboratory as well as in remote, automated crystal growth laboratory. Its small volume, light-weight, and low power requirements are sufficient to have it installed in unique environments, i.e.. on-board International Space Station.

Fast Growth of GaN Epilayers via Laser-Assisted Metal-Organic Chemical Vapor Deposition for Ultraviolet Photodetector Applications.

PubMed

Rabiee Golgir, Hossein; Li, Da Wei; Keramatnejad, Kamran; Zou, Qi Ming; Xiao, Jun; Wang, Fei; Jiang, Lan; Silvain, Jean-François; Lu, Yong Feng

2017-06-28

In this study, we successfully developed a carbon dioxide (CO 2 )-laser-assisted metal-organic chemical vapor deposition (LMOCVD) approach to fast synthesis of high-quality gallium nitride (GaN) epilayers on Al 2 O 3 [sapphire(0001)] substrates. By employing a two-step growth procedure, high crystallinity and smooth GaN epilayers with a fast growth rate of 25.8 μm/h were obtained. The high crystallinity was confirmed by a combination of techniques, including X-ray diffraction, Raman spectroscopy, transmission electron microscopy, and atomic force microscopy. By optimizing growth parameters, the ∼4.3-μm-thick GaN films grown at 990 °C for 10 min showed a smooth surface with a root-mean-square surface roughness of ∼1.9 nm and excellent thickness uniformity with sharp GaN/substrate interfaces. The full-width at half-maximum values of the GaN(0002) X-ray rocking curve of 313 arcsec and the GaN(101̅2) X-ray rocking curve of 390 arcsec further confirmed the high crystallinity of the GaN epilayers. We also fabricated ultraviolet (UV) photodetectors based on the as-grown GaN layers, which exhibited a high responsivity of 0.108 A W -1 at 367 nm and a fast response time of ∼125 ns, demonstrating its high optical quality with potential in optoelectronic applications. Our strategy thus provides a simple and cost-effective means toward fast and high-quality GaN heteroepitaxy growth suitable for fabricating high-performance GaN-based UV detectors.

Characterization of ion beam sputtered deposited W/Si multilayers by grazing incidence x-ray diffraction and x-ray reflectivity technique

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dhawan, Rajnish, E-mail: rajnish@rrcat.gov.in; Rai, Sanjay

2016-05-23

W/Si multilayers four samples have been deposited on silicon substrate using ion beam sputtering system. Thickness of tungsten (W) varies from around 10 Å to 40 Å while the silicon (Si) thickness remains constant at around 30 Å in multilayers [W-Si]{sub x4}. The samples have been characterized by grazing incidence X-ray diffraction (GIXRD) and X-ray reflectivity technique (XRR). GIXRD study shows the crystalline behaviour of W/Si multilayer by varying W thickness and it is found that above 20 Å the W film transform from amorphous to crystalline phase and X-ray reflectivity data shows that the roughnesses of W increases onmore » increasing the W thicknesses in W/Si multilayers.« less

Large angle solid state position sensitive x-ray detector system

DOEpatents

Kurtz, David S.; Ruud, Clay O.

1998-01-01

A method and apparatus for x-ray measurement of certain properties of a solid material. In distinction to known methods and apparatus, this invention employs a specific fiber-optic bundle configuration, termed a reorganizer, itself known for other uses, for coherently transmitting visible light originating from the scintillation of diffracted x-radiation from the solid material gathered along a substantially one dimensional linear arc, to a two-dimensional photo-sensor array. The two-dimensional photodetector array, with its many closely packed light sensitive pixels, is employed to process the information contained in the diffracted radiation and present the information in the form of a conventional x-ray diffraction spectrum. By this arrangement, the angular range of the combined detector faces may be increased without loss of angular resolution. Further, the prohibitively expensive coupling together of a large number of individual linear diode photodetectors, which would be required to process signals generated by the diffracted radiation, is avoided.

Hard X-ray irradiation of cosmic silicate analogs: structural evolution and astrophysical implications

NASA Astrophysics Data System (ADS)

Gavilan, L.; Jäger, C.; Simionovici, A.; Lemaire, J. L.; Sabri, T.; Foy, E.; Yagoubi, S.; Henning, T.; Salomon, D.; Martinez-Criado, G.

2016-03-01

Context. Protoplanetary disks, interstellar clouds, and active galactic nuclei contain X-ray-dominated regions. X-rays interact with the dust and gas present in such environments. While a few laboratory X-ray irradiation experiments have been performed on ices, X-ray irradiation experiments on bare cosmic dust analogs have been scarce up to now. Aims: Our goal is to study the effects of hard X-rays on cosmic dust analogs via in situ X-ray diffraction. By using a hard X-ray synchrotron nanobeam, we seek to simulate cumulative X-ray exposure on dust grains during their lifetime in these astrophysical environments and provide an upper limit on the effect of hard X-rays on dust grain structure. Methods: We prepared enstatite (MgSiO3) nanograins, which are analogs to cosmic silicates, via the melting-quenching technique. These amorphous grains were then annealed to obtain polycrystalline grains. These were characterized via scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (HRTEM) before irradiation. Powder samples were prepared in X-ray transparent substrates and were irradiated with hard X-rays nanobeams (29.4 keV) provided by beamline ID16B of the European Synchrotron Radiation Facility (Grenoble). X-ray diffraction images were recorded in transmission mode, and the ensuing diffractograms were analyzed as a function of the total X-ray exposure time. Results: We detected the amorphization of polycrystalline silicates embedded in an organic matrix after an accumulated X-ray exposure of 6.4 × 1027 eV cm-2. Pure crystalline silicate grains (without resin) do not exhibit amorphization. None of the amorphous silicate samples (pure and embedded in resin) underwent crystallization. We analyze the evolution of the polycrystalline sample embedded in an organic matrix as a function of X-ray exposure. Conclusions: Loss of diffraction peak intensity, peak broadening, and the disappearance of discrete spots and arcs reveal the amorphization of the resin embedded (originally polycrystalline) silicate sample. We explore the astrophysical implications of this laboratory result as an upper limit to the effect of X-rays on the structure of cosmic silicates.

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

DOE PAGES

Fan, D.; Huang, J. W.; Zeng, X. L.; ...

2016-05-23

We develop a mini gas gun system for simultaneous, single-pulse, x-ray diffraction and imaging under high strain-rate loading at the beamline 32-ID of the Advanced Photon Source. In order to increase the reciprocal space covered by a small-area detector, a conventional target chamber is split into two chambers: a narrowed measurement chamber and a relief chamber. The gas gun impact is synchronized with synchrotron x-ray pulses and high-speed cameras. Depending on a camera’s capability, multiframe imaging and diffraction can be achieved. The proof-of-principle experiments are performed on single-crystal sapphire. The diffraction spots and images during impact are analyzed to quantifymore » lattice deformation and fracture; diffraction peak broadening is largely caused by fracture-induced strain inhomogeneity. Finally, our results demonstrate the potential of such multiscale measurements for revealing and understanding high strain-rate phenomena at dynamic extremes.« less

Single photon energy dispersive x-ray diffraction

DOE Office of Scientific and Technical Information (OSTI.GOV)

Higginbotham, Andrew; Patel, Shamim; Ciricosta, Orlando

2014-03-15

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

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fan, D.; Huang, J. W.; Zeng, X. L.

We develop a mini gas gun system for simultaneous, single-pulse, x-ray diffraction and imaging under high strain-rate loading at the beamline 32-ID of the Advanced Photon Source. In order to increase the reciprocal space covered by a small-area detector, a conventional target chamber is split into two chambers: a narrowed measurement chamber and a relief chamber. The gas gun impact is synchronized with synchrotron x-ray pulses and high-speed cameras. Depending on a camera’s capability, multiframe imaging and diffraction can be achieved. The proof-of-principle experiments are performed on single-crystal sapphire. The diffraction spots and images during impact are analyzed to quantifymore » lattice deformation and fracture; diffraction peak broadening is largely caused by fracture-induced strain inhomogeneity. Finally, our results demonstrate the potential of such multiscale measurements for revealing and understanding high strain-rate phenomena at dynamic extremes.« less

X-ray spectrometer having 12 000 resolving power at 8 keV energy

NASA Astrophysics Data System (ADS)

Seely, John F.; Hudson, Lawrence T.; Henins, Albert; Feldman, Uri

2017-10-01

An x-ray spectrometer employing a thin (50 μm) silicon transmission crystal was used to record high-resolution Cu Kα spectra from a laboratory x-ray source. The diffraction was from the (331) planes that were at an angle of 13.26° to the crystal surface. The components of the spectral lines resulting from single-vacancy (1s) and double-vacancy (1s and 3d) transitions were observed. After accounting for the natural lifetime widths from reference double-crystal spectra and the spatial resolution of the image plate detector, the intrinsic broadening of the transmission crystal was measured to be as small as 0.67 eV and the resolving power 12 000, the highest resolving power achieved by a compact (0.5 m long) spectrometer employing a single transmission crystal operating in the hard x-ray region. By recording spectra with variable source-to-crystal distances and comparing to the calculated widths from various geometrical broadening mechanisms, the primary contributions to the intrinsic crystal broadening were found to be the source height at small distances and the crystal apertured height at large distances. By reducing these two effects, using a smaller source size and vignetting the crystal height, the intrinsic crystal broadening is then limited by the crystal thickness and the rocking curve width and would be 0.4 eV at 8 keV energy (20 000 resolving power).

Origin of Pressure-induced Superconducting Phase in K xFe 2-ySe 2 studied by Synchrotron X-ray Diffraction and Spectroscopy

DOE PAGES

Yamamoto, Yoshiya; Yamaoka, Hitoshi; Tanaka, Masashi; ...

2016-08-08

Pressure dependence of the electronic and crystal structures of K xFe 2–ySe 2, which has pressure-induced two superconducting domes of SC I and SC II, was investigated by x-ray emission spectroscopy and diffraction. X-ray diffraction data show that compressibility along the c-axis changes around 12 GPa, where a new superconducting phase of SC II appears. This suggests a possible tetragonal to collapsed tetragonal phase transition. X-ray emission spectroscopy data also shows the change in the electronic structure around 12 GPa. These results can be explained by the scenario that the two SC domes under pressure originate from the change ofmore » Fermi surface topology. Lastly, our results here show the pronounced increase of the density of states near the Fermi surface under pressure with a structural phase transition, which can help address our fundamental understanding for the appearance of the SC II phase.« less

Synthesis, growth, structural, optical, spectral, thermal and mechanical studies of 4-methoxy 4-nitrostilbene (MONS): a new organic nonlinear optical single crystal.

PubMed

Dinakaran, Paul M; Bhagavannarayana, G; Kalainathan, S

2012-11-01

4-Methoxy 4-nitrostilbene (MONS), a new organic nonlinear optical material has been synthesized. Based on the solubility data good quality single crystal with dimensions up to 38×11×3 mm(3) has been grown by slow evaporation method using ethyl methyl ketone (MEK) as a solvent. Powder XRD confirms the crystalline property and also the diffraction planes have been indexed. The lattice parameters for the grown MONS crystals were determined by using single crystal X-ray diffraction analysis and it reveals that the crystal lattice system is triclinic. The crystalline perfection of the grown crystals has been analysed by high resolution X-ray diffraction (HRXRD) rocking curve measurements. Fourier transform infrared (FTIR) spectrum for powdered MONS sample confirms the functional groups present in the grown crystal. The UV-vis absorption spectrum has been recorded in the range of 190-1100 nm and the cut off wavelength 499 nm has been determined. The optical constants of MONS have been determined through UV-vis-NIR spectroscopy. The MONS crystals were further subjected to other characterizations. i.e., (1)H NMR, TG/DTA, photoluminescence and microhardness test. The Kurtz and Perry powder technique confirms the NLO property of the grown crystal and the SHG efficiency of MONS was found to be 1.55× greater than that of KDP crystal. Copyright © 2012 Elsevier B.V. All rights reserved.

Cryo diffraction microscopy: Ice conditions and finite supports

DOE PAGES

Miao, H.; Downing, K.; Huang, X.; ...

2009-09-25

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

Layered-to-Rock-Salt Transformation in Desodiated Na xCrO 2 ( x 0.4)

DOE PAGES

Bo, Shou-Hang; Li, Xin; Toumar, Alexandra J.; ...

2016-02-01

O3 layered sodium transition metal oxides (i.e., NaMO 2, M = Ti, V, Cr, Mn, Fe, Co, Ni) are a promising class of cathode materials for Na-ion battery applications. These materials, however, all suffer from severe capacity decay when the extraction of Na exceeds certain capacity limits. Understanding the causes of this capacity decay is critical to unlocking the potential of these materials for battery applications. In this work, we investigate the structural origins of capacity decay for one of the compounds in this class, NaCrO 2. The (de)sodiation processes of NaCrO 2 were studied both in situ and exmore » situ through X-ray and electron diffraction measurements. We demonstrate that Na xCrO 2 (0 < x < 1) remains in the layered structural framework without Cr migration up to a composition of Na 0.4CrO 2. Further removal of Na beyond this composition triggers a layered-to-rock-salt transformation, which converts P'3-Na 0.4CrO 2 into the rock-salt CrO 2 phase. This structural transformation proceeds via the formation of an intermediate O3 Na δCrO 2 phase that contains Cr in both Na and Cr slabs and shares very similar lattice dimensions with those of rock-salt CrO 2. It is intriguing to note that intercalation of alkaline ions (i.e., Na + and Li + ) into the rock-salt CrO 2 and O3 Na δCrO 2 structures is actually possible, albeit in a limited amount (~0.2 per formula unit). When these results were analyzed under the context of electrochemistry data, it was apparent that preventing the layered-to-rock-salt transformation is crucial to improve the cyclability of NaCrO 2. Possible strategies for mitigating this detrimental phase transition are proposed.« less

Publications - GMC 40 | Alaska Division of Geological & Geophysical Surveys

Science.gov Websites

DGGS GMC 40 Publication Details Title: X-ray diffraction analysis of the Pan Am Hoodoo Lake #2; Pan Am , X-ray diffraction analysis of the Pan Am Hoodoo Lake #2; Pan Am David River #1-A; and the AMOCO

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

NASA Technical Reports Server (NTRS)

Vaniman, D. T.; Bristow, T. F.; Bish, D. L.; Ming, D. W.; Blake, D. F.; Morris, R. V.; Rampe, E. B.; Chipera, S. J.; Treiman, A. H.; Morrison, S. M.;

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

USDA-ARS?s Scientific Manuscript database

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

Three-dimensional structure determination protocol for noncrystalline biomolecules using x-ray free-electron laser diffraction imaging.

PubMed

Oroguchi, Tomotaka; Nakasako, Masayoshi

2013-02-01

Coherent and intense x-ray pulses generated by x-ray free-electron laser (XFEL) sources are paving the way for structural determination of noncrystalline biomolecules. However, due to the small scattering cross section of electrons for x rays, the available incident x-ray intensity of XFEL sources, which is currently in the range of 10(12)-10(13) photons/μm(2)/pulse, is lower than that necessary to perform single-molecule diffraction experiments for noncrystalline biomolecules even with the molecular masses of megadalton and submicrometer dimensions. Here, we propose an experimental protocol and analysis method for visualizing the structure of those biomolecules by the combined application of coherent x-ray diffraction imaging and three-dimensional reconstruction methods. To compensate the small scattering cross section of biomolecules, in our protocol, a thin vitreous ice plate containing several hundred biomolecules/μm(2) is used as sample, a setup similar to that utilized by single-molecule cryoelectron microscopy. The scattering cross section of such an ice plate is far larger than that of a single particle. The images of biomolecules contained within irradiated areas are then retrieved from each diffraction pattern, and finally provide the three-dimensional electron density model. A realistic atomic simulation using large-scale computations proposed that the three-dimensional structure determination of the 50S ribosomal subunit embedded in a vitreous ice plate is possible at a resolution of 0.8 nm when an x-ray beam of 10(16) photons/500×500 nm(2)/pulse is available.

Organic Photonics: Toward a New Generation of Thin Film Photovoltaics and Lasers

DTIC Science & Technology

2011-03-07

plane. 39 Both electron and x - ray diffraction confirm the existence of crystalline domains of CuPc and C60. Crystalline domain sizes range from 5...nanocrystalline domains indicated by white curves that locate the domain boundaries. Scale bar=5 nm. b, X - ray diffraction pattern of an OVPD grown A... ray diffraction (XRD) and atomic force microscopy (AFM), as shown in Fig. 8. A cross-sectional TEM image of [CuPc(6.1nm)/C60(6.1nm)]10 is shown in

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

NASA Technical Reports Server (NTRS)

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

1978-01-01

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

TAKASAGO-6 apparatus for cryogenic coherent X-ray diffraction imaging of biological non-crystalline particles using X-ray free electron laser at SACLA

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kobayashi, Amane; Sekiguchi, Yuki; Oroguchi, Tomotaka

Coherent X-ray diffraction imaging (CXDI) is a technique for structure analyses of non-crystalline particles with dimensions ranging from micrometer to sub-micrometer. We have developed a diffraction apparatus named TAKASAGO-6 for use in single-shot CXDI experiments of frozen-hydrated non-crystalline biological particles at cryogenic temperature with X-ray free electron laser pulses provided at a repetition rate of 30 Hz from the SPring-8 Angstrom Compact free-electron LAser. Specimen particles are flash-cooled after being dispersed on thin membranes supported by specially designed disks. The apparatus is equipped with a high-speed translation stage with a cryogenic pot for raster-scanning of the disks at a speedmore » higher than 25 μm/33 ms. In addition, we use devices assisting the easy transfer of cooled specimens from liquid-nitrogen storages to the cryogenic pot. In the current experimental procedure, more than 20 000 diffraction patterns can be collected within 1 h. Here we report the key components and performance of the diffraction apparatus. Based on the efficiency of the diffraction data collection and the structure analyses of metal particles, biological cells, and cellular organelles, we discuss the future application of this diffraction apparatus for structure analyses of biological specimens.« less

Grating-based holographic diffraction methods for X-rays and neutrons: phase object approximation and dynamical theory

DOE PAGES

Feng, Hao; Ashkar, Rana; Steinke, Nina; ...

2018-02-01

A method dubbed grating-based holography was recently used to determine the structure of colloidal fluids in the rectangular grooves of a diffraction grating from X-ray scattering measurements. Similar grating-based measurements have also been recently made with neutrons using a technique called spin-echo small-angle neutron scattering. The analysis of the X-ray diffraction data was done using an approximation that treats the X-ray phase change caused by the colloidal structure as a small perturbation to the overall phase pattern generated by the grating. In this paper, the adequacy of this weak phase approximation is explored for both X-ray and neutron grating holography.more » Additionally, it is found that there are several approximations hidden within the weak phase approximation that can lead to incorrect conclusions from experiments. In particular, the phase contrast for the empty grating is a critical parameter. Finally, while the approximation is found to be perfectly adequate for X-ray grating holography experiments performed to date, it cannot be applied to similar neutron experiments because the latter technique requires much deeper grating channels.« less

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

NASA Technical Reports Server (NTRS)

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

1999-01-01

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

Imaging whole Escherichia coli bacteria by using single-particle x-ray diffraction

NASA Astrophysics Data System (ADS)

Miao, Jianwei; Hodgson, Keith O.; Ishikawa, Tetsuya; Larabell, Carolyn A.; Legros, Mark A.; Nishino, Yoshinori

2003-01-01

We report the first experimental recording, to our knowledge, of the diffraction pattern from intact Escherichia coli bacteria using coherent x-rays with a wavelength of 2 Å. By using the oversampling phasing method, a real space image at a resolution of 30 nm was directly reconstructed from the diffraction pattern. An R factor used for characterizing the quality of the reconstruction was in the range of 5%, which demonstrated the reliability of the reconstruction process. The distribution of proteins inside the bacteria labeled with manganese oxide has been identified and this distribution confirmed by fluorescence microscopy images. Compared with lens-based microscopy, this diffraction-based imaging approach can examine thicker samples, such as whole cultured cells, in three dimensions with resolution limited only by radiation damage. Looking forward, the successful recording and reconstruction of diffraction patterns from biological samples reported here represent an important step toward the potential of imaging single biomolecules at near-atomic resolution by combining single-particle diffraction with x-ray free electron lasers.

Quantitative disentanglement of coherent and incoherent laser-induced surface deformations by time-resolved x-ray reflectivity

NASA Astrophysics Data System (ADS)

Sander, M.; Pudell, J.-E.; Herzog, M.; Bargheer, M.; Bauer, R.; Besse, V.; Temnov, V.; Gaal, P.

2017-12-01

We present time-resolved x-ray reflectivity measurements on laser excited coherent and incoherent surface deformations of thin metallic films. Based on a kinematical diffraction model, we derive the surface amplitude from the diffracted x-ray intensity and resolve transient surface excursions with sub-Å spatial precision and 70 ps temporal resolution. The analysis allows for decomposition of the surface amplitude into multiple coherent acoustic modes and a substantial contribution from incoherent phonons which constitute the sample heating.

Structural studies of liquid Co–Sn alloys

PubMed Central

Yakymovych, A.; Shtablavyi, I.; Mudry, S.

2014-01-01

An analysis of the structure features of liquid Co–Sn alloys has been performed by means of X-ray diffraction method, viscosity coefficient analysis and computer simulation method. The X-ray diffraction investigations were carried out over a wide concentration range at the temperature 1473 K. It was found that the structure of these alloys can be described in the frame of independent X-ray scattering model. The viscosity coefficient was calculated by an excess entropy scaling and compared with experimental data. PMID:25328282

Quantitative determination of mineral composition by powder x-ray diffraction

DOEpatents

Pawloski, G.A.

1984-08-10

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

Quantitative determination of mineral composition by powder X-ray diffraction

DOEpatents

Pawloski, Gayle A.

1986-01-01

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

The Influence of Growth Temperature on Sb Incorporation in InAsSb, and the Temperature-dependent Impact of Bi Surfactants

DTIC Science & Technology

2014-01-01

resolution X - ray diffraction (XRD) were collected for all samples, and reciprocal space maps (RSMs) were collected from selected samples. The complete data...exposure. The lines represent the model fit. 19 13 Figure 1. Triple axis x - ray diffraction from the bi-layered InAsSb structures grown on GaSb at...Applied Physics, Structural properties of bismuth‐bearing semiconductor alloys, 63 (1988) 107. 18 12 Figure Captions Figure 1. Triple axis x - ray

Effects of Peripheral Architecture on the Properties of Aryl Polyhedral Oligomeric Silsesquioxanes

DTIC Science & Technology

2012-07-26

POSS) molecules are described. These POSS materials were synthesized in our laboratory and characterized by single-crystal and powder X - ray diffraction ...powder X - ray diffraction (XRD), where applicable. 1H, 13C, and 29Si NMR spectra were obtained on Bruker 300 and 400 MHz spectrometers using 5 mm o.d...degree of cage ordering during precipitation. Referring back to Figure 14, strong X - ray scattering peaks in the spectra for 1 in the d- spacing range

Étude de la structure des alliages vitreux Ag-As2S3 par diffraction de rayons X

NASA Astrophysics Data System (ADS)

Popescu, M.; Sava, F.; Cornet, A.; Broll, N.

2002-07-01

The structure of several silver alloyed arsenic chalocgenide has been determined by X-ray diffraction. For low silver doping the disordered layer structure, characteristic to the glassy AS2S3 is retained as demonstrated by the well developed first sharp diffraction peak in the X-ray diffraction pattern. For high amount of silver introduced in the As2S3 matrix, the disoredered layer configurations disappear, as shown by the diminishing and even disappearance of the first sharp diffraction peak in the X-ray patterns. A three-dimensional structure based on Ag2S -type configuration is formed. La structure de quelques alliages sulfure d'arsenic - argent a été determinée par diffraction de rayons X. Pour de faibles dopages à l'argent on conserve la structure desordonnées caractéristique des couches atomique d'As2S3 vitreux ; ceci est prouvé par la forte intensité du premier pic étroit de diffraction. Pour des plus grandes proportions d'argent la structure de l'alliage vitreux fait apparaître des unités structurales caractéristiques du cristal d'Ag2S et la configuration atomique avec des couches desordonnées disparaît (le premier pic étroit de diffraction s'évanouit) en faisant place à une structure tridimensionelle.

Development of variable-magnification X-ray Bragg optics.

PubMed

Hirano, Keiichi; Yamashita, Yoshiki; Takahashi, Yumiko; Sugiyama, Hiroshi

2015-07-01

A novel X-ray Bragg optics is proposed for variable-magnification of an X-ray beam. This X-ray Bragg optics is composed of two magnifiers in a crossed arrangement, and the magnification factor, M, is controlled through the azimuth angle of each magnifier. The basic properties of the X-ray optics such as the magnification factor, image transformation matrix and intrinsic acceptance angle are described based on the dynamical theory of X-ray diffraction. The feasibility of the variable-magnification X-ray Bragg optics was verified at the vertical-wiggler beamline BL-14B of the Photon Factory. For X-ray Bragg magnifiers, Si(220) crystals with an asymmetric angle of 14° were used. The magnification factor was calculated to be tunable between 0.1 and 10.0 at a wavelength of 0.112 nm. At various magnification factors (M ≥ 1.0), X-ray images of a nylon mesh were observed with an air-cooled X-ray CCD camera. Image deformation caused by the optics could be corrected by using a 2 × 2 transformation matrix and bilinear interpolation method. Not only absorption-contrast but also edge-contrast due to Fresnel diffraction was observed in the magnified images.

On the Habitability of Desert Varnish: A Combined Study by Micro-Raman Spectroscopy, X-ray Diffraction, and Methylated Pyrolysis-Gas Chromatography-Mass Spectrometry

NASA Astrophysics Data System (ADS)

Malherbe, C.; Hutchinson, I. B.; Ingley, R.; Boom, A.; Carr, A. S.; Edwards, H.; Vertruyen, B.; Gilbert, B.; Eppe, G.

2017-11-01

In 2020, the ESA ExoMars and NASA Mars 2020 missions will be launched to Mars to search for evidence of past and present life. In preparation for these missions, terrestrial analog samples of rock formations on Mars are studied in detail in order to optimize the scientific information that the analytical instrumentation will return. Desert varnishes are thin mineral coatings found on rocks in arid and semi-arid environments on Earth that are recognized as analog samples. During the formation of desert varnishes (which takes many hundreds of years), organic matter is incorporated, and microorganisms may also play an active role in the formation process. During this study, four complementary analytical techniques proposed for Mars missions (X-ray diffraction [XRD], Raman spectroscopy, elemental analysis, and pyrolysis-gas chromatography-mass spectrometry [Py-GC-MS]) were used to interrogate samples of desert varnish and describe their capacity to sustain life under extreme scenarios. For the first time, both the geochemistry and the organic compounds associated with desert varnish are described with the use of identical sets of samples. XRD and Raman spectroscopy measurements were used to nondestructively interrogate the mineralogy of the samples. In addition, the use of Raman spectroscopy instruments enabled the detection of β-carotene, a highly Raman-active biomarker. The content and the nature of the organic material in the samples were further investigated with elemental analysis and methylated Py-GC-MS, and a bacterial origin was determined to be likely. In the context of planetary exploration, we describe the habitable nature of desert varnish based on the biogeochemical composition of the samples. Possible interference of the geological substrate on the detectability of pyrolysis products is also suggested.

X-ray phase contrast imaging of objects with subpixel-size inhomogeneities: a geometrical optics model.

PubMed

Gasilov, Sergei V; Coan, Paola

2012-09-01

Several x-ray phase contrast extraction algorithms use a set of images acquired along the rocking curve of a perfect flat analyzer crystal to study the internal structure of objects. By measuring the angular shift of the rocking curve peak, one can determine the local deflections of the x-ray beam propagated through a sample. Additionally, some objects determine a broadening of the crystal rocking curve, which can be explained in terms of multiple refraction of x rays by many subpixel-size inhomogeneities contained in the sample. This fact may allow us to differentiate between materials and features characterized by different refraction properties. In the present work we derive an expression for the beam broadening in the form of a linear integral of the quantity related to statistical properties of the dielectric susceptibility distribution function of the object.

Synthesis and characterization of (1-x)Bi(Mg{sub 2/3}Sb{sub 1/3})O{sub 3}-xPbTiO{sub 3} piezoceramics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Upadhyay, Ashutosh; Dwivedi, Saurabh; Pandey, Rishikesh

2016-05-23

We present here the comprehensive x-ray diffraction and polarization-electric field hysteresis studies on (1-x)Bi(Mg{sub 2/3}Sb{sub 1/3})O{sub 3}-xPbTiO{sub 3} piezoceramics with x = 0.52, 0.56 and 0.60. The powder x-ray diffraction data reveals the presence of tetragonal phase for all the compositions. The saturation of hysteresis loop is observed for x ≤ 0.56.

Three-dimensional electron diffraction as a complementary technique to powder X-ray diffraction for phase identification and structure solution of powders.

PubMed

Yun, Yifeng; Zou, Xiaodong; Hovmöller, Sven; Wan, Wei

2015-03-01

Phase identification and structure determination are important and widely used techniques in chemistry, physics and materials science. Recently, two methods for automated three-dimensional electron diffraction (ED) data collection, namely automated diffraction tomography (ADT) and rotation electron diffraction (RED), have been developed. Compared with X-ray diffraction (XRD) and two-dimensional zonal ED, three-dimensional ED methods have many advantages in identifying phases and determining unknown structures. Almost complete three-dimensional ED data can be collected using the ADT and RED methods. Since each ED pattern is usually measured off the zone axes by three-dimensional ED methods, dynamic effects are much reduced compared with zonal ED patterns. Data collection is easy and fast, and can start at any arbitrary orientation of the crystal, which facilitates automation. Three-dimensional ED is a powerful technique for structure identification and structure solution from individual nano- or micron-sized particles, while powder X-ray diffraction (PXRD) provides information from all phases present in a sample. ED suffers from dynamic scattering, while PXRD data are kinematic. Three-dimensional ED methods and PXRD are complementary and their combinations are promising for studying multiphase samples and complicated crystal structures. Here, two three-dimensional ED methods, ADT and RED, are described. Examples are given of combinations of three-dimensional ED methods and PXRD for phase identification and structure determination over a large number of different materials, from Ni-Se-O-Cl crystals, zeolites, germanates, metal-organic frameworks and organic compounds to intermetallics with modulated structures. It is shown that three-dimensional ED is now as feasible as X-ray diffraction for phase identification and structure solution, but still needs further development in order to be as accurate as X-ray diffraction. It is expected that three-dimensional ED methods will become crucially important in the near future.

Chemistry of rocks and soils at Meridiani Planum from the Alpha Particle X-ray Spectrometer.

PubMed

Rieder, R; Gellert, R; Anderson, R C; Brückner, J; Clark, B C; Dreibus, G; Economou, T; Klingelhöfer, G; Lugmair, G W; Ming, D W; Squyres, S W; d'Uston, C; Wänke, H; Yen, A; Zipfel, J

2004-12-03

The Alpha Particle X-ray Spectrometer on the Opportunity rover determined major and minor elements of soils and rocks in Meridiani Planum. Chemical compositions differentiate between basaltic rocks, evaporite-rich rocks, basaltic soils, and hematite-rich soils. Although soils are compositionally similar to those at previous landing sites, differences in iron and some minor element concentrations signify the addition of local components. Rocky outcrops are rich in sulfur and variably enriched in bromine relative to chlorine. The interaction with water in the past is indicated by the chemical features in rocks and soils at this site.

Geological sources of fluoride and acceptable intake of fluoride in an endemic fluorosis area, southern Iran.

PubMed

Battaleb-Looie, Sedigheh; Moore, Farid; Jacks, Gunnar; Ketabdari, Mohammad Reza

2012-10-01

The present study is the first attempt to put forward possible source(s) of fluoride in the Dashtestan area, Bushehr Province, southern Iran. In response to reports on the high incidence of dental fluorosis, 35 surface and groundwater samples were collected and analysed for fluoride. The results indicate that dissolved fluoride in the study area is above the maximum permissible limit recommended by the World Health Organization (WHO). An additional 35 soil and rock samples were also collected and analysed for fluoride, and rock samples were subjected to petrographic investigations and X-ray diffraction. The results of these analyses show that the most likely source for fluoride in the groundwater is from clay minerals (chlorite) and micas (muscovite, sericite, and biotite) in the soils and rocks in the area. We also note that due to the high average temperatures all year round and excessive water consumption in the area, the optimum fluoride dose level should be lower than that recommended by the WHO.

Femtosecond X-ray Fourier holography imaging of free-flying nanoparticles

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gorkhover, Tais; Ulmer, Anatoli; Ferguson, Ken

Ultrafast X-ray imaging on individual fragile specimens such as aerosols, metastable particles, superfluid quantum systems and live biospecimens provides high-resolution information that is inaccessible with conventional imaging techniques. Coherent X-ray diffractive imaging, however, suffers from intrinsic loss of phase, and therefore structure recovery is often complicated and not always uniquely defined. Here in this paper, we introduce the method of in-flight holography, where we use nanoclusters as reference X-ray scatterers to encode relative phase information into diffraction patterns of a virus. The resulting hologram contains an unambiguous three-dimensional map of a virus and two nanoclusters with the highest lateral resolutionmore » so far achieved via single shot X-ray holography. Our approach unlocks the benefits of holography for ultrafast X-ray imaging of nanoscale, non-periodic systems and paves the way to direct observation of complex electron dynamics down to the attosecond timescale.« less

Calculation of x-ray scattering patterns from nanocrystals at high x-ray intensity

PubMed Central

Abdullah, Malik Muhammad; Jurek, Zoltan; Son, Sang-Kil; Santra, Robin

2016-01-01

We present a generalized method to describe the x-ray scattering intensity of the Bragg spots in a diffraction pattern from nanocrystals exposed to intense x-ray pulses. Our method involves the subdivision of a crystal into smaller units. In order to calculate the dynamics within every unit, we employ a Monte-Carlo-molecular dynamics-ab-initio hybrid framework using real space periodic boundary conditions. By combining all the units, we simulate the diffraction pattern of a crystal larger than the transverse x-ray beam profile, a situation commonly encountered in femtosecond nanocrystallography experiments with focused x-ray free-electron laser radiation. Radiation damage is not spatially uniform and depends on the fluence associated with each specific region inside the crystal. To investigate the effects of uniform and non-uniform fluence distribution, we have used two different spatial beam profiles, Gaussian and flattop. PMID:27478859

Femtosecond X-ray Fourier holography imaging of free-flying nanoparticles

NASA Astrophysics Data System (ADS)

Gorkhover, Tais; Ulmer, Anatoli; Ferguson, Ken; Bucher, Max; Maia, Filipe R. N. C.; Bielecki, Johan; Ekeberg, Tomas; Hantke, Max F.; Daurer, Benedikt J.; Nettelblad, Carl; Andreasson, Jakob; Barty, Anton; Bruza, Petr; Carron, Sebastian; Hasse, Dirk; Krzywinski, Jacek; Larsson, Daniel S. D.; Morgan, Andrew; Mühlig, Kerstin; Müller, Maria; Okamoto, Kenta; Pietrini, Alberto; Rupp, Daniela; Sauppe, Mario; van der Schot, Gijs; Seibert, Marvin; Sellberg, Jonas A.; Svenda, Martin; Swiggers, Michelle; Timneanu, Nicusor; Westphal, Daniel; Williams, Garth; Zani, Alessandro; Chapman, Henry N.; Faigel, Gyula; Möller, Thomas; Hajdu, Janos; Bostedt, Christoph

2018-03-01

Ultrafast X-ray imaging on individual fragile specimens such as aerosols1, metastable particles2, superfluid quantum systems3 and live biospecimens4 provides high-resolution information that is inaccessible with conventional imaging techniques. Coherent X-ray diffractive imaging, however, suffers from intrinsic loss of phase, and therefore structure recovery is often complicated and not always uniquely defined4,5. Here, we introduce the method of in-flight holography, where we use nanoclusters as reference X-ray scatterers to encode relative phase information into diffraction patterns of a virus. The resulting hologram contains an unambiguous three-dimensional map of a virus and two nanoclusters with the highest lateral resolution so far achieved via single shot X-ray holography. Our approach unlocks the benefits of holography for ultrafast X-ray imaging of nanoscale, non-periodic systems and paves the way to direct observation of complex electron dynamics down to the attosecond timescale.

Femtosecond X-ray Fourier holography imaging of free-flying nanoparticles

DOE PAGES

Gorkhover, Tais; Ulmer, Anatoli; Ferguson, Ken; ...

2018-02-26

Ultrafast X-ray imaging on individual fragile specimens such as aerosols, metastable particles, superfluid quantum systems and live biospecimens provides high-resolution information that is inaccessible with conventional imaging techniques. Coherent X-ray diffractive imaging, however, suffers from intrinsic loss of phase, and therefore structure recovery is often complicated and not always uniquely defined. Here in this paper, we introduce the method of in-flight holography, where we use nanoclusters as reference X-ray scatterers to encode relative phase information into diffraction patterns of a virus. The resulting hologram contains an unambiguous three-dimensional map of a virus and two nanoclusters with the highest lateral resolutionmore » so far achieved via single shot X-ray holography. Our approach unlocks the benefits of holography for ultrafast X-ray imaging of nanoscale, non-periodic systems and paves the way to direct observation of complex electron dynamics down to the attosecond timescale.« less

CARNAÚBA: The Coherent X-Ray Nanoprobe Beamline for the Brazilian Synchrotron SIRIUS/LNLS

NASA Astrophysics Data System (ADS)

Tolentino, Hélio C. N.; Soares, Márcio M.; Perez, Carlos A.; Vicentin, Flávio C.; Abdala, Dalton B.; Galante, Douglas; Teixeira, Verônica de C.; de Araújo, Douglas H. C.; Westfahl, Harry, Jr.

2017-06-01

The CARNAÚBA beamline is the tender-to-hard X-ray (2 - 15 keV) scanning nanoprobe planned for the 4th generation storage ring SIRIUS at the LNLS. CARNAÚBA uses an undulator source with vertical linear polarization in a low-beta straight section and grazing incidence-focusing mirrors to create a nanoprobe at 143 m from the source. The beamline optic is based on KB mirrors and provides high brilliance at an achromatic focal spot down to the diffraction limit diameter of ˜30 nm with a working distance of ˜6 cm. These characteristics are crucial for studying nanometric samples in experiments involving complex stages and environments. The CARNAÚBA beamline aims to perform raster scans using x-ray fluorescence, x-ray absorption spectroscopy, x-ray diffraction and coherent x-ray imaging techniques. Computed tomography will extend these methods to three dimensions.

An in situ X ray diffraction study of the kinetics of the Ni2SiO4 olivine-spinel transformation

NASA Technical Reports Server (NTRS)

Rubie, D. C.; Tsuchida, Y.; Yagi, T.; Utsumi, W.; Kikegawa, T.

1990-01-01

The kinetics of the olivine-spinel transformation in Ni2SiO4 were investigated in an in situ X-ray diffraction experiments in which synchrotron radiation was used as an X-ray source. The starting material was Ni2SO4 olivine which was hot-pressed in situ at 980 C and 2.5 GPa; during the transformation, X-ray diffraction patterns were collected at intervals of 30 or 120 sec. The kinetic data were analyzed using Cahn's (1956) model. The activation energy for growth at 3.6-3.7 GPa was estimated as 438 + or - 199 kJ/mol. It is shown that, in order to make significant extrapolations of the kinetic data to a geological scale, the dependence of the rates of both nucleation and growth on temperature and pressure must be evaluated separately.

Hydrothermal formation of tobermorite studied by in situ X-ray diffraction under autoclave condition.

PubMed

Kikuma, Jun; Tsunashima, Masamichi; Ishikawa, Tetsuji; Matsuno, Shin-ya; Ogawa, Akihiro; Matsui, Kunio; Sato, Masugu

2009-09-01

Hydrothermal formation of tobermorite from a pre-cured cake has been investigated by transmission X-ray diffraction (XRD) using high-energy X-rays from a synchrotron radiation source in combination with a newly designed autoclave cell. The autoclave cell has a large and thin beryllium window for wide-angle X-ray diffraction; nevertheless, it withstands a steam pressure of more than 1.2 MPa, which enables in situ XRD measurements in a temperature range of 373 to 463 K under a saturated steam pressure. Formation and/or decomposition of several components has been successfully observed during 7.5 h of reaction time. From the intensity changes of the intermediate materials, namely non-crystalline C-S-H and hydroxylellestadite, two pathways for tobermorite formation have been confirmed. Thus, the newly developed autoclave cell can be used for the analyses of reaction mechanisms under specific atmospheres and temperatures.

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

NASA Astrophysics Data System (ADS)

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

2010-08-01

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

Pink-beam serial crystallography

DOE Office of Scientific and Technical Information (OSTI.GOV)

Meents, A.; Wiedorn, M. O.; Srajer, V.

Serial X-ray crystallography allows macromolecular structure determination at both X-ray free electron lasers (XFELs) and, more recently, synchrotron sources. The time resolution for serial synchrotron crystallography experiments has been limited to millisecond timescales with monochromatic beams. The polychromatic, “pink”, beam provides a more than two orders of magnitude increased photon flux and hence allows accessing much shorter timescales in diffraction experiments at synchrotron sources. Here we report the structure determination of two different protein samples by merging pink-beam diffraction patterns from many crystals, each collected with a single 100 ps X-ray pulse exposure per crystal using a setup optimized formore » very low scattering background. In contrast to experiments with monochromatic radiation, data from only 50 crystals were required to obtain complete datasets. The high quality of the diffraction data highlights the potential of this method for studying irreversible reactions at sub-microsecond timescales using high-brightness X-ray facilities.« less

Pink-beam serial crystallography

DOE PAGES

Meents, A.; Wiedorn, M. O.; Srajer, V.; ...

2017-11-03

Serial X-ray crystallography allows macromolecular structure determination at both X-ray free electron lasers (XFELs) and, more recently, synchrotron sources. The time resolution for serial synchrotron crystallography experiments has been limited to millisecond timescales with monochromatic beams. The polychromatic, “pink”, beam provides a more than two orders of magnitude increased photon flux and hence allows accessing much shorter timescales in diffraction experiments at synchrotron sources. Here we report the structure determination of two different protein samples by merging pink-beam diffraction patterns from many crystals, each collected with a single 100 ps X-ray pulse exposure per crystal using a setup optimized formore » very low scattering background. In contrast to experiments with monochromatic radiation, data from only 50 crystals were required to obtain complete datasets. The high quality of the diffraction data highlights the potential of this method for studying irreversible reactions at sub-microsecond timescales using high-brightness X-ray facilities.« less

X-ray nanoprobes and diffraction-limited storage rings: opportunities and challenges of fluorescence tomography of biological specimens

PubMed Central

de Jonge, Martin D.; Ryan, Christopher G.; Jacobsen, Chris J.

2014-01-01

X-ray nanoprobes require coherent illumination to achieve optic-limited resolution, and so will benefit directly from diffraction-limited storage rings. Here, the example of high-resolution X-ray fluorescence tomography is focused on as one of the most voracious demanders of coherent photons, since the detected signal is only a small fraction of the incident flux. Alternative schemes are considered for beam delivery, sample scanning and detectors. One must consider as well the steps before and after the X-ray experiment: sample preparation and examination conditions, and analysis complexity due to minimum dose requirements and self-absorption. By understanding the requirements and opportunities for nanoscale fluorescence tomography, one gains insight into the R&D challenges in optics and instrumentation needed to fully exploit the source advances that diffraction-limited storage rings offer. PMID:25177992

Simulations of in situ x-ray diffraction from uniaxially compressed highly textured polycrystalline targets

DOE Office of Scientific and Technical Information (OSTI.GOV)

McGonegle, David, E-mail: d.mcgonegle1@physics.ox.ac.uk; Wark, Justin S.; Higginbotham, Andrew

2015-08-14

A growing number of shock compression experiments, especially those involving laser compression, are taking advantage of in situ x-ray diffraction as a tool to interrogate structure and microstructure evolution. Although these experiments are becoming increasingly sophisticated, there has been little work on exploiting the textured nature of polycrystalline targets to gain information on sample response. Here, we describe how to generate simulated x-ray diffraction patterns from materials with an arbitrary texture function subject to a general deformation gradient. We will present simulations of Debye-Scherrer x-ray diffraction from highly textured polycrystalline targets that have been subjected to uniaxial compression, as maymore » occur under planar shock conditions. In particular, we study samples with a fibre texture, and find that the azimuthal dependence of the diffraction patterns contains information that, in principle, affords discrimination between a number of similar shock-deformation mechanisms. For certain cases, we compare our method with results obtained by taking the Fourier transform of the atomic positions calculated by classical molecular dynamics simulations. Illustrative results are presented for the shock-induced α–ϵ phase transition in iron, the α–ω transition in titanium and deformation due to twinning in tantalum that is initially preferentially textured along [001] and [011]. The simulations are relevant to experiments that can now be performed using 4th generation light sources, where single-shot x-ray diffraction patterns from crystals compressed via laser-ablation can be obtained on timescales shorter than a phonon period.« less

Simulations of in situ x-ray diffraction from uniaxially compressed highly textured polycrystalline targets

DOE PAGES

McGonegle, David; Milathianaki, Despina; Remington, Bruce A.; ...

2015-08-11

A growing number of shock compression experiments, especially those involving laser compression, are taking advantage of in situ x-ray diffraction as a tool to interrogate structure and microstructure evolution. Although these experiments are becoming increasingly sophisticated, there has been little work on exploiting the textured nature of polycrystalline targets to gain information on sample response. Here, we describe how to generate simulated x-ray diffraction patterns from materials with an arbitrary texture function subject to a general deformation gradient. We will present simulations of Debye-Scherrer x-ray diffraction from highly textured polycrystalline targets that have been subjected to uniaxial compression, as maymore » occur under planar shock conditions. In particular, we study samples with a fibre texture, and find that the azimuthal dependence of the diffraction patterns contains information that, in principle, affords discrimination between a number of similar shock-deformation mechanisms. For certain cases, we compare our method with results obtained by taking the Fourier transform of the atomic positions calculated by classical molecular dynamics simulations. Illustrative results are presented for the shock-induced α–ϵ phase transition in iron, the α–ω transition in titanium and deformation due to twinning in tantalum that is initially preferentially textured along [001] and [011]. In conclusion, the simulations are relevant to experiments that can now be performed using 4th generation light sources, where single-shot x-ray diffraction patterns from crystals compressed via laser-ablation can be obtained on timescales shorter than a phonon period.« less

MUDMASTER: A Program for Calculating Crystalline Size Distributions and Strain from the Shapes of X-Ray Diffraction Peaks

USGS Publications Warehouse

Eberl, D.D.; Drits, V.A.; Środoń, Jan; Nüesch, R.

1996-01-01

Particle size may strongly influence the physical and chemical properties of a substance (e.g. its rheology, surface area, cation exchange capacity, solubility, etc.), and its measurement in rocks may yield geological information about ancient environments (sediment provenance, degree of metamorphism, degree of weathering, current directions, distance to shore, etc.). Therefore mineralogists, geologists, chemists, soil scientists, and others who deal with clay-size material would like to have a convenient method for measuring particle size distributions. Nano-size crystals generally are too fine to be measured by light microscopy. Laser scattering methods give only average particle sizes; therefore particle size can not be measured in a particular crystallographic direction. Also, the particles measured by laser techniques may be composed of several different minerals, and may be agglomerations of individual crystals. Measurement by electron and atomic force microscopy is tedious, expensive, and time consuming. It is difficult to measure more than a few hundred particles per sample by these methods. This many measurements, often taking several days of intensive effort, may yield an accurate mean size for a sample, but may be too few to determine an accurate distribution of sizes. Measurement of size distributions by X-ray diffraction (XRD) solves these shortcomings. An X-ray scan of a sample occurs automatically, taking a few minutes to a few hours. The resulting XRD peaks average diffraction effects from billions of individual nano-size crystals. The size that is measured by XRD may be related to the size of the individual crystals of the mineral in the sample, rather than to the size of particles formed from the agglomeration of these crystals. Therefore one can determine the size of a particular mineral in a mixture of minerals, and the sizes in a particular crystallographic direction of that mineral.

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

NASA Astrophysics Data System (ADS)

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 "colors" of each Laue spot, which enable phase identification. The concept was demonstrated with prototypes and dedicated crystallographic software was developed for identification the minerals responsible for the Laue patterns. High TRL subsystems are under development for future deployment opportunities of these new XRD instruments.

Experimental Approaches for Solution X-Ray Scattering and Fiber Diffraction

PubMed Central

Irving, T. C.

2008-01-01

X-ray scattering and diffraction from non-crystalline systems have gained renewed interest in recent years, as focus shifts from the structural chemistry information gained by high-resolution studies to the context of structural physiology at larger length scales. Such techniques permit the study of isolated macromolecules as well as highly organized macromolecular assemblies as a whole under near-physiological conditions. Time-resolved approaches, made possible by advanced synchrotron instrumentation, add a critical dimension to many of these investigations. This article reviews experimental approaches in non-crystalline x-ray scattering and diffraction that may be used to illuminate important scientific questions such as protein/nucleic acid folding and structure-function relationships in large macromolecular assemblies. PMID:18801437

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nishitani, Yuichi; Maruyama, Daisuke; Nonaka, Tsuyoshi

2006-04-01

Preliminary X-ray diffraction studies on N-acetylglucosamine-phosphate mutase from C. albicans are reported. N-acetylglucosamine-phosphate mutase (AGM1) is an essential enzyme in the synthesis of UDP-N-acetylglucosamine (UDP-GlcNAc) in eukaryotes and belongs to the α-d-phosphohexomutase superfamily. AGM1 from Candida albicans (CaAGM1) was purified and crystallized by the sitting-drop vapour-diffusion method. The crystals obtained belong to the primitive monoclinic space group P2{sub 1}, with unit-cell parameters a = 60.2, b = 130.2, c = 78.0 Å, β = 106.7°. The crystals diffract X-rays to beyond 1.8 Å resolution using synchrotron radiation.

Crystallographic Characterization of Extraterrestrial Materials by Energy-Scanning X-ray Diffraction

NASA Technical Reports Server (NTRS)

Hagiya, Kenji; Mikouchi, Takashi; Ohsumi, Kazumasa; Terada, Yasuko; Yagi, Naoto; Komatsu, Mutsumi; Yamaguchi, Shoki; Hirata, Arashi; Kurokawa, Ayaka; Zolensky, Michael E. (Principal Investigator)

2016-01-01

We have continued our long-term project using X-ray diffraction to characterize a wide range of extraterrestrial samples. The stationary sample method with polychromatic X-rays is advantageous because the irradiated area of the sample is always same and fixed, meaning that all diffraction spots occur from the same area of the sample, however, unit cell parameters cannot be directly obtained by this method though they are very important for identification of mineral and for determination of crystal structures. In order to obtain the cell parameters even in the case of the sample stationary method, we apply energy scanning of a micro-beam of monochromatic SR at SPring-8.

Synchrotron X-ray studies of the keel of the short-spined sea urchin Lytechinus variegatus: absorption microtomography (microCT) and small beam diffraction mapping.

PubMed

Stock, S R; Barss, J; Dahl, T; Veis, A; Almer, J D; Carlo, F

2003-05-01

In sea urchin teeth, the keel plays an important structural role, and this paper reports results of microstructural characterization of the keel of Lytechinus variegatus using two noninvasive synchrotron x-ray techniques: x-ray absorption microtomography (microCT) and x-ray diffraction mapping. MicroCT with 14 keV x-rays mapped the spatial distribution of mineral at the 1.3 microm level in a millimeter-sized fragment of a mature portion of the keel. Two rows of low absorption channels (i.e., primary channels) slightly less than 10 microm in diameter were found running linearly from the flange to the base of the keel and parallel to its sides. The primary channels paralleled the oral edge of the keel, and the microCT slices revealed a planar secondary channel leading from each primary channel to the side of the keel. The primary and secondary channels were more or less coplanar and may correspond to the soft tissue between plates of the carinar process. Transmission x-ray diffraction with 80.8 keV x-rays and a 0.1 mm beam mapped the distribution of calcite crystal orientations and the composition Ca(1-x)Mg(x)CO(3) of the calcite. Unlike the variable Mg concentration and highly curved prisms found in the keel of Paracentrotus lividus, a constant Mg content (x = 0.13) and relatively little prism curvature was found in the keel of Lytechinus variegatus.

Density of bunched threading dislocations in epitaxial GaN layers as determined using X-ray diffraction

NASA Astrophysics Data System (ADS)

Barchuk, M.; Holý, V.; Rafaja, D.

2018-04-01

X-ray diffraction is one of the most popular experimental methods employed for determination of dislocation densities, as it can recognize both the strain fields and the local lattice rotations produced by dislocations. The main challenge of the quantitative analysis of the dislocation density is the formulation of a suitable microstructure model, which describes the dislocation arrangement and the effect of the interactions between the strain fields from neighboring dislocations reliably in order to be able to determine the dislocation densities precisely. The aim of this study is to prove the capability of X-ray diffraction and two computational methods, which are frequently used for quantification of the threading dislocation densities from X-ray diffraction measurements, in the special case of partially bunched threading dislocations. The first method is based on the analysis of the dislocation-controlled crystal mosaicity, and the other one on the analysis of diffuse X-ray scattering from threading dislocations. The complementarity of both methods is discussed. Furthermore, it is shown how the complementarity of these methods can be used to improve the results of the quantitative analysis of bunched and thus inhomogeneously distributed threading dislocations and to get a better insight into the dislocation arrangement.

Femtosecond X-ray protein nanocrystallography.

PubMed

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

2011-02-03

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

Nanoscale Fresnel coherent diffraction imaging tomography using ptychography.

PubMed

Peterson, I; Abbey, B; Putkunz, C T; Vine, D J; van Riessen, G A; Cadenazzi, G A; Balaur, E; Ryan, R; Quiney, H M; McNulty, I; Peele, A G; Nugent, K A

2012-10-22

We demonstrate Fresnel Coherent Diffractive Imaging (FCDI) tomography in the X-ray regime. The method uses an incident X-ray illumination with known curvature in combination with ptychography to overcome existing problems in diffraction imaging. The resulting tomographic reconstruction represents a 3D map of the specimen's complex refractive index at nano-scale resolution. We use this technique to image a lithographically fabricated glass capillary, in which features down to 70nm are clearly resolved.

Standards for Analysis of Ce, La, Pb, Rb, Se, Sr, Y, AND Zr in Rock Samples Using Laser-induced Breakdown Spectroscopy and X-ray Fluorescence

NASA Technical Reports Server (NTRS)

Mackie, Jason; Dyar, M. Darby; Ytsma, Caroline; Lepore, Kate; Fassett, Caleb I.; Hanlon, Avery; Wagoner, Carlie; Treiman, Allan

2017-01-01

Analytical geochemistry has long depended on the availability of robust suites of rock standards with well-characterized compositions. Standard rock powders for wet chemistry and x-ray fluorescence were initially characterized and supplied to the community by the U.S. Geological Survey, which continues to distribute a few dozen standards. Many other rock standards have subsequently been developed by organizations such as the Centre de Recherches Pétrographiques et Géochimiques (CRPG) and Brammer Standard Company, Inc.

Synchrotron applications in wood preservation and deterioration

Treesearch

Barbara L. Illman

2003-01-01

Several non-intrusive synchrotron techniques are being used to detect and study wood decay. The techniques use high intensity synchrotron-generated X-rays to determine the atomic structure of materials with imaging, diffraction, and absorption. Some of the techniques are X-ray absorption near edge structure (XANES), X-ray fluorescence spectroscopy (XFS), X-ray...

Microscopy of biological sample through advanced diffractive optics from visible to X-ray wavelength regime.

PubMed

Di Fabrizio, Enzo; Cojoc, Dan; Emiliani, Valentina; Cabrini, Stefano; Coppey-Moisan, Maite; Ferrari, Enrico; Garbin, Valeria; Altissimo, Matteo

2004-11-01

The aim of this report is to demonstrate a unified version of microscopy through the use of advanced diffractive optics. The unified scheme derives from the technical possibility of realizing front wave engineering in a wide range of electromagnetic spectrum. The unified treatment is realized through the design and nanofabrication of phase diffractive elements (PDE) through which wave front beam shaping is obtained. In particular, we will show applications, by using biological samples, ranging from micromanipulation using optical tweezers to X-ray differential interference contrast (DIC) microscopy combined with X-ray fluorescence. We report some details on the design and physical implementation of diffractive elements that besides focusing also perform other optical functions: beam splitting, beam intensity, and phase redistribution or mode conversion. Laser beam splitting is used for multiple trapping and independent manipulation of micro-beads surrounding a cell as an array of tweezers and for arraying and sorting microscopic size biological samples. Another application is the Gauss to Laguerre-Gauss mode conversion, which allows for trapping and transfering orbital angular momentum of light to micro-particles immersed in a fluid. These experiments are performed in an inverted optical microscope coupled with an infrared laser beam and a spatial light modulator for diffractive optics implementation. High-resolution optics, fabricated by means of e-beam lithography, are demonstrated to control the intensity and the phase of the sheared beams in x-ray DIC microscopy. DIC experiments with phase objects reveal a dramatic increase in image contrast compared to bright-field x-ray microscopy. Besides the topographic information, fluorescence allows detection of certain chemical elements (Cl, P, Sc, K) in the same setup, by changing the photon energy of the x-ray beam. (c) 2005 Wiley-Liss, Inc.

A Practical Guide for the Preparation of Specimens for X-ray Fluorescence and X-ray Diffraction Analysis (by V. E. Buhrke, R. Jenkins, and D. K. Smith)

NASA Astrophysics Data System (ADS)

Rudman, Reuben

1999-06-01

Wiley-VCH: New York, 1998. xxiv + 333 pp. ISBN 0-471-19458-1. $79.95. I would have subtitled this book "All You Ever Wanted To Know about ...Sample Preparation". Although its principal thrust is geared towards the analytical chemist in an X-ray diffraction (XRD) or X-ray fluorescence (XRF) service laboratory, this text will be of use primarily as a reference source in all milieus dealing with undergraduate research projects and advanced laboratory courses in physical and analytical chemistry. It contains dozens of suggestions for preparing randomly oriented small samples of nearly anything. For example, rocks and minerals, soft organics and hard ceramics, radioactive and liquid materials, metals and oils are all treated. As the availability of XRD and XRF equipment has increased, so has the use of these techniques in the teaching schedule. Many undergraduate laboratory and research projects utilizing these methods have been described in the literature and are found in laboratory textbooks. Very often, especially with the increasingly common use of automated computer-controlled instrumentation, sample preparation has become the key experimental technique required for successful data collection. However, it is not always easy to prepare the statistically random distribution of small particles (crystallites) that is required by these methods. A multitude of techniques have been developed over the past 70 years, but many of them have been handed down by word of mouth or are scattered throughout the literature. This book represents an attempt to systematically describe the theory and practice of sample preparation. This excellent guide to the intricacies of sample preparation begins with a description of statistical sampling methods and the principles of grinding techniques. After a discussion of XRF specimen preparation, which includes pressing pellets, fusion methods, crucible selection and handling very small samples, detailed descriptions for handling rocks, minerals, cements, metals, oils, and vegetation [sic] are given. The preparation of XRD samples is described for various diffraction equipment geometries (utilizing both counter and film detectors), including specific information regarding the use of flat specimens and slurries, the use of internal standards, and the effects of crystallite size on the diffraction pattern. Methods for handling ceramics, clays, zeolites, air-sensitive samples, thin films, and plastics are described, along with the special handling requirements for materials to be studied by high-pressure, high-temperature, or low-temperature techniques. One whole chapter is devoted to the equipment used in specimen preparation, including grinders, pulverizers, presses, specimen holders, repair of platinumware, and sources of all types of special equipment. Did you ever want to know where to get a Plattner steel mortar or a micronizing mill or soft-glass capillary tubes with 0.01-mm wall thickness? It's all here in this monograph. The book ends with a good glossary of terms, a general bibliography in addition to the extensive list of references following each of its 9 chapters, and an index. It will be of help in many areas of spectroscopy and analytical chemistry, as well as in XRD and XRF analyses.

X-ray crystallography

NASA Technical Reports Server (NTRS)

2001-01-01

X-rays diffracted from a well-ordered protein crystal create sharp patterns of scattered light on film. A computer can use these patterns to generate a model of a protein molecule. To analyze the selected crystal, an X-ray crystallographer shines X-rays through the crystal. Unlike a single dental X-ray, which produces a shadow image of a tooth, these X-rays have to be taken many times from different angles to produce a pattern from the scattered light, a map of the intensity of the X-rays after they diffract through the crystal. The X-rays bounce off the electron clouds that form the outer structure of each atom. A flawed crystal will yield a blurry pattern; a well-ordered protein crystal yields a series of sharp diffraction patterns. From these patterns, researchers build an electron density map. With powerful computers and a lot of calculations, scientists can use the electron density patterns to determine the structure of the protein and make a computer-generated model of the structure. The models let researchers improve their understanding of how the protein functions. They also allow scientists to look for receptor sites and active areas that control a protein's function and role in the progress of diseases. From there, pharmaceutical researchers can design molecules that fit the active site, much like a key and lock, so that the protein is locked without affecting the rest of the body. This is called structure-based drug design.

Daniel Shechtman and Quasicrystals

Science.gov Websites

toolbox that included transmission electron microscopy, X-ray diffraction and neutron diffraction. The searchQuery x Find DOE R&D Acccomplishments Navigation dropdown arrow The Basics dropdown arrow Home About Letters, Vol. 53, Issue 20: 1951-1953; November 12, 1984 Nuclear γ-ray resonance observations in an

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

ERIC Educational Resources Information Center

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

2007-01-01

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

Crystallographic Study of Itokawa Particle, RA-QD02-0127 by Using Energy-Scanning X-Ray Diffraction Method with Synchrotron Radiation

NASA Astrophysics Data System (ADS)

Hagiya, K.; Ohsumi, K.; Komatsu, M.; Mikouchi, T.; Zolensky, M. E.; Hirata, A.; Yamaguchi, S.; Kurokawa, A.

2016-08-01

Crystallographic study of Itokawa particle, RA-QD02-0127 by using new X-ray diffraction method was performed. The purpose of this study is to understand better the metamorphic and impact shock history of asteroid Itokawa, and other S-class asteroids.

Noble Gas Isotopic Signatures and X-Ray and Electron Diffraction Characteristics of Tagish Lake Carbonaceous Chondrite

NASA Technical Reports Server (NTRS)

Nakamura, T.; Noguchi, T.; Zolensky, M. E.; Takaoka, N.

2001-01-01

Noble gas isotopic signatures and X-ray and electron diffraction characteristics of Tagish Lake indicate that it is a unique carbonaceous chondrite rich in saponite, Fe-Mg-Ca carbonate, primordial noble gases, and presolar grains. Additional information is contained in the original extended abstract.

Method of Generating X-Ray Diffraction Data for Integral Detection of Twin Defects in Super-Hetero-Epitaxial Materials

NASA Technical Reports Server (NTRS)

Park, Yeonjoon (Inventor); Choi, Sang Hyouk (Inventor); King, Glen C. (Inventor); Elliott, James R. (Inventor)

2009-01-01

A method provides X-ray diffraction (XRD) data suitable for integral detection of a twin defect in a strained or lattice-matched epitaxial material made from components having crystal structures having symme try belonging to different space groups. The material is mounted in a n X-ray diffraction (XRD) system. In one embodiment, the XRD system's goniometer angle Omega is set equal to (Theta(sub B)-Beta) where The ta(sub B) is a Bragg angle for a designated crystal plane of the allo y that is disposed at a non-perpendicular orientation with respect to the {111) crystal plane, and Beta is the angle between the designate d crystal plane and a { 111 } crystal plane of one of the epitaxial components. The XRD system's detector angle is set equal to (Theta(su b B)+Beta). The material can be rotated through an angle of azimuthal rotation Phi about the axis aligned with the material. Using the det ector, the intensity of the X-ray diffraction is recorded at least at the angle at which the twin defect occurs.

A study of mercuric iodide near melting using differential scanning calorimetry, Raman spectroscopy and X-ray diffraction

NASA Astrophysics Data System (ADS)

Burger, A.; Morgan, S.; Jiang, H.; Silberman, E.; Schieber, M.; Van Den Berg, L.; Keller, L.; Wagner, C. N. J.

1989-11-01

High-temperature studies of mercuric iodide (HgI2) involving differential scanning calorimetry (DSC), Raman spectroscopy and X-ray powder diffraction have failed to confirm the existence of a red-colored tetragonal high-temperature phase called α'-HgI2 reported by S.N. Toubektsis et al. [J. Appl. Phys. 58 (1988) 2070] using DSC measurements. The multiple DSC peaks near melting reported by Toubektsis are found by the present authors only if the sample is heated in a stainless-steel container. Using a Pyrex container or inserting a platinum foil between the HgI2 and the stainless-steel container yields only one sharp, single DSC peak at the melting point. The nonexistence of the α' phase is confirmed by high-temperature X-ray diffraction and Raman spectroscopy performed in the vicinity of the melting point. These methods clearly, indicate the existence of only the yellow orthorhombic β-HgI2 phase. The experimental high-temperature DSC, Raman and X-ray diffraction data are presented and discussed.

ELECTRON MICROSCOPE AND X-RAY DIFFRACTION STUDIES ON A HOMOLOGOUS SERIES OF SATURATED PHOSPHATIDYLCHOLINES.

PubMed

ELBERS, P F; VERVERGAERT, P H

1965-05-01

Three homologous saturated phosphatidylcholines were studied by electron microscopy after tricomplex fixation. The results are compared with those obtained by x-ray diffraction analysis of the same and some other homologous compounds, in the dry crystalline state and after tricomplex fixation. By electron microscopy alternating dark and light bands are observed which are likely to correspond to phosphatide double layers. X-Ray diffraction reveals the presence of lamellar structures of regular spacing. The layer spacings obtained by both methods are in good agreement. From the electron micrographs the width of the polar parts of the double layers can be derived directly. The width of the carboxylglycerylphosphorylcholine moiety of the layers is found by extrapolating the x-ray diffraction data to zero chain length of the fatty acids. When from this width the contribution of the carboxylglyceryl part of the molecules is subtracted, again we find good agreement with the electron microscope measurements. An attempt has been made to account for the different layer spacings measured in terms of orientation of the molecules within the double layers.

Complete elliptical ring geometry provides energy and instrument calibration for synchrotron-based two-dimensional X-ray diffraction

PubMed Central

Hart, Michael L.; Drakopoulos, Michael; Reinhard, Christina; Connolley, Thomas

2013-01-01

A complete calibration method to characterize a static planar two-dimensional detector for use in X-ray diffraction at an arbitrary wavelength is described. This method is based upon geometry describing the point of intersection between a cone’s axis and its elliptical conic section. This point of intersection is neither the ellipse centre nor one of the ellipse focal points, but some other point which lies in between. The presented solution is closed form, algebraic and non-iterative in its application, and gives values for the X-ray beam energy, the sample-to-detector distance, the location of the beam centre on the detector surface and the detector tilt relative to the incident beam. Previous techniques have tended to require prior knowledge of either the X-ray beam energy or the sample-to-detector distance, whilst other techniques have been iterative. The new calibration procedure is performed by collecting diffraction data, in the form of diffraction rings from a powder standard, at known displacements of the detector along the beam path. PMID:24068840

Role of Molecular Structure on X-ray Diffraction in Thermotropic Uniaxial and Biaxial Nematic Liquid Crystal Phases

DOE Office of Scientific and Technical Information (OSTI.GOV)

Acharya, Bharat R.; Kang, Shin-Woong; Prasad, Veena

2009-08-27

X-ray diffraction is one of the most definitive methods to determine the structure of condensed matter phases, and it has been applied to unequivocally infer the structures of conventional calamitic and lyotropic liquid crystals. With the advent of bent-core and tetrapodic mesogens and the discovery of the biaxial nematic phase in them, the experimental results require more careful interpretation and analysis. Here, we present ab-initio calculations of X-ray diffraction patterns in the isotropic, uniaxial nematic, and biaxial nematic phases of bent-core mesogens. A simple Meier-Saupe-like molecular distribution function is employed to describe both aligned and unaligned mesophases. The distribution functionmore » is decomposed into two, polar and azimuthal, distribution functions to calculate the effect of the evolution of uniaxial and biaxial nematic orientational order. The calculations provide satisfactory semiquantitative interpretations of experimental results. The calculations presented here should provide a pathway to more refined and quantitative analysis of X-ray diffraction data from the biaxial nematic phase.« less

Role of Molecular Structure on X-ray Diffraction in Uniaxial and Biaxial Phases of Thermotropic Liquid Crystals

DOE Office of Scientific and Technical Information (OSTI.GOV)

Acharya, Bharat R.; Kang, Shin-Woong; Prasad, Veena

2009-04-29

X-ray diffraction is one of the most definitive methods to determine the structure of condensed matter phases, and it has been applied to unequivocally infer the structures of conventional calamitic and lyotropic liquid crystals. With the advent of bent-core and tetrapodic mesogens and the discovery of the biaxial nematic phase in them, the experimental results require more careful interpretation and analysis. Here, we present ab-initio calculations of X-ray diffraction patterns in the isotropic, uniaxial nematic, and biaxial nematic phases of bent-core mesogens. A simple Meier-Saupe-like molecular distribution function is employed to describe both aligned and unaligned mesophases. The distribution functionmore » is decomposed into two, polar and azimuthal, distribution functions to calculate the effect of the evolution of uniaxial and biaxial nematic orientational order. The calculations provide satisfactory semiquantitative interpretations of experimental results. The calculations presented here should provide a pathway to more refined and quantitative analysis of X-ray diffraction data from the biaxial nematic phase.« less

Effect of exit beam phase aberrations on coherent x-ray reconstructions of Au nanocrystals

NASA Astrophysics Data System (ADS)

Hruszkewycz, Stephan; Harder, Ross; Fuoss, Paul

2010-03-01

Current studies in coherent x-ray diffractive imaging (CXDI) are focusing on in-situ imaging under a variety of environmental conditions. Such studies often involve environmental sample chambers through which the x-ray beam must pass before and after interacting with the sample: i.e. cryostats or high pressure cells. Such sample chambers usually contain polycrystalline x-ray windows with structural imperfections that can in turn interact with the diffracted beam. A phase object in the near field that interacts with the beam exiting the sample can introduce distortions at the detector plane that may affect coherent reconstructions. We investigate the effects of a thin beryllium membrane on the coherent exit beam of a gold nanoparticle. We compare three dimensional reconstructions from experimental diffraction patterns measured with and without a 380 micron thick Be dome and find that the reconstructions are reproducible within experimental errors. Simulated near-field distortions of the exit beam consistent with micron sized voids in Be establish a ``worst case scenario'' where distorted diffraction patterns inhibit accurate inversions.

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

DOE PAGES

Beetz, T.; Howells, M. R.; Jacobsen, C.; ...

2005-03-14

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

Effect of screw threading dislocations and inverse domain boundaries in GaN on the shape of reciprocal-space maps.

PubMed

Barchuk, Mykhailo; Motylenko, Mykhaylo; Lukin, Gleb; Pätzold, Olf; Rafaja, David

2017-04-01

The microstructure of polar GaN layers, grown by upgraded high-temperature vapour phase epitaxy on [001]-oriented sapphire substrates, was studied by means of high-resolution X-ray diffraction and transmission electron microscopy. Systematic differences between reciprocal-space maps measured by X-ray diffraction and those which were simulated for different densities of threading dislocations revealed that threading dislocations are not the only microstructure defect in these GaN layers. Conventional dark-field transmission electron microscopy and convergent-beam electron diffraction detected vertical inversion domains as an additional microstructure feature. On a series of polar GaN layers with different proportions of threading dislocations and inversion domain boundaries, this contribution illustrates the capability and limitations of coplanar reciprocal-space mapping by X-ray diffraction to distinguish between these microstructure features.

Open data set of live cyanobacterial cells imaged using an X-ray laser

NASA Astrophysics Data System (ADS)

van der Schot, Gijs; Svenda, Martin; Maia, Filipe R. N. C.; Hantke, Max F.; Deponte, Daniel P.; Seibert, M. Marvin; Aquila, Andrew; Schulz, Joachim; Kirian, Richard A.; Liang, Mengning; Stellato, Francesco; Bari, Sadia; Iwan, Bianca; Andreasson, Jakob; Timneanu, Nicusor; Bielecki, Johan; Westphal, Daniel; Nunes de Almeida, Francisca; Odić, Duško; Hasse, Dirk; Carlsson, Gunilla H.; Larsson, Daniel S. D.; Barty, Anton; Martin, Andrew V.; Schorb, Sebastian; Bostedt, Christoph; Bozek, John D.; Carron, Sebastian; Ferguson, Ken; Rolles, Daniel; Rudenko, Artem; Epp, Sascha W.; Foucar, Lutz; Rudek, Benedikt; Erk, Benjamin; Hartmann, Robert; Kimmel, Nils; Holl, Peter; Englert, Lars; Loh, N. Duane; Chapman, Henry N.; Andersson, Inger; Hajdu, Janos; Ekeberg, Tomas

2016-08-01

Structural studies on living cells by conventional methods are limited to low resolution because radiation damage kills cells long before the necessary dose for high resolution can be delivered. X-ray free-electron lasers circumvent this problem by outrunning key damage processes with an ultra-short and extremely bright coherent X-ray pulse. Diffraction-before-destruction experiments provide high-resolution data from cells that are alive when the femtosecond X-ray pulse traverses the sample. This paper presents two data sets from micron-sized cyanobacteria obtained at the Linac Coherent Light Source, containing a total of 199,000 diffraction patterns. Utilizing this type of diffraction data will require the development of new analysis methods and algorithms for studying structure and structural variability in large populations of cells and to create abstract models. Such studies will allow us to understand living cells and populations of cells in new ways. New X-ray lasers, like the European XFEL, will produce billions of pulses per day, and could open new areas in structural sciences.

Open data set of live cyanobacterial cells imaged using an X-ray laser.

PubMed

van der Schot, Gijs; Svenda, Martin; Maia, Filipe R N C; Hantke, Max F; DePonte, Daniel P; Seibert, M Marvin; Aquila, Andrew; Schulz, Joachim; Kirian, Richard A; Liang, Mengning; Stellato, Francesco; Bari, Sadia; Iwan, Bianca; Andreasson, Jakob; Timneanu, Nicusor; Bielecki, Johan; Westphal, Daniel; Nunes de Almeida, Francisca; Odić, Duško; Hasse, Dirk; Carlsson, Gunilla H; Larsson, Daniel S D; Barty, Anton; Martin, Andrew V; Schorb, Sebastian; Bostedt, Christoph; Bozek, John D; Carron, Sebastian; Ferguson, Ken; Rolles, Daniel; Rudenko, Artem; Epp, Sascha W; Foucar, Lutz; Rudek, Benedikt; Erk, Benjamin; Hartmann, Robert; Kimmel, Nils; Holl, Peter; Englert, Lars; Loh, N Duane; Chapman, Henry N; Andersson, Inger; Hajdu, Janos; Ekeberg, Tomas

2016-08-01

Structural studies on living cells by conventional methods are limited to low resolution because radiation damage kills cells long before the necessary dose for high resolution can be delivered. X-ray free-electron lasers circumvent this problem by outrunning key damage processes with an ultra-short and extremely bright coherent X-ray pulse. Diffraction-before-destruction experiments provide high-resolution data from cells that are alive when the femtosecond X-ray pulse traverses the sample. This paper presents two data sets from micron-sized cyanobacteria obtained at the Linac Coherent Light Source, containing a total of 199,000 diffraction patterns. Utilizing this type of diffraction data will require the development of new analysis methods and algorithms for studying structure and structural variability in large populations of cells and to create abstract models. Such studies will allow us to understand living cells and populations of cells in new ways. New X-ray lasers, like the European XFEL, will produce billions of pulses per day, and could open new areas in structural sciences.

CheMin Instrument Performance and Calibration on Mars

NASA Technical Reports Server (NTRS)

Vaniman, D. T.; Blake, D. F.; Morookian, J. M.; Yen, A. S.; Ming, D. W.; Morris, R. V.; Achilles, C. N.; Bish, D. L.; Chipera, S. J.; Morrison, S. M.;

A Curved Image-Plate Detector System for High-Resolution Synchrotron X-ray Diffraction

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sarin, P.; Haggerty, R; Yoon, W

2009-01-01

The developed curved image plate (CIP) is a one-dimensional detector which simultaneously records high-resolution X-ray diffraction (XRD) patterns over a 38.7 2{theta} range. In addition, an on-site reader enables rapid extraction, transfer and storage of X-ray intensity information in {le}30 s, and further qualifies this detector to study kinetic processes in materials science. The CIP detector can detect and store X-ray intensity information linearly proportional to the incident photon flux over a dynamical range of about five orders of magnitude. The linearity and uniformity of the CIP detector response is not compromised in the unsaturated regions of the image plate,more » regardless of saturation in another region. The speed of XRD data acquisition together with excellent resolution afforded by the CIP detector is unique and opens up wide possibilities in materials research accessible through X-ray diffraction. This article presents details of the basic features, operation and performance of the CIP detector along with some examples of applications, including high-temperature XRD.« less

Open data set of live cyanobacterial cells imaged using an X-ray laser

PubMed Central

van der Schot, Gijs; Svenda, Martin; Maia, Filipe R.N.C.; Hantke, Max F.; DePonte, Daniel P.; Seibert, M. Marvin; Aquila, Andrew; Schulz, Joachim; Kirian, Richard A.; Liang, Mengning; Stellato, Francesco; Bari, Sadia; Iwan, Bianca; Andreasson, Jakob; Timneanu, Nicusor; Bielecki, Johan; Westphal, Daniel; Nunes de Almeida, Francisca; Odić, Duško; Hasse, Dirk; Carlsson, Gunilla H.; Larsson, Daniel S.D.; Barty, Anton; Martin, Andrew V.; Schorb, Sebastian; Bostedt, Christoph; Bozek, John D.; Carron, Sebastian; Ferguson, Ken; Rolles, Daniel; Rudenko, Artem; Epp, Sascha W.; Foucar, Lutz; Rudek, Benedikt; Erk, Benjamin; Hartmann, Robert; Kimmel, Nils; Holl, Peter; Englert, Lars; Loh, N. Duane; Chapman, Henry N.; Andersson, Inger; Hajdu, Janos; Ekeberg, Tomas

2016-01-01

Structural studies on living cells by conventional methods are limited to low resolution because radiation damage kills cells long before the necessary dose for high resolution can be delivered. X-ray free-electron lasers circumvent this problem by outrunning key damage processes with an ultra-short and extremely bright coherent X-ray pulse. Diffraction-before-destruction experiments provide high-resolution data from cells that are alive when the femtosecond X-ray pulse traverses the sample. This paper presents two data sets from micron-sized cyanobacteria obtained at the Linac Coherent Light Source, containing a total of 199,000 diffraction patterns. Utilizing this type of diffraction data will require the development of new analysis methods and algorithms for studying structure and structural variability in large populations of cells and to create abstract models. Such studies will allow us to understand living cells and populations of cells in new ways. New X-ray lasers, like the European XFEL, will produce billions of pulses per day, and could open new areas in structural sciences. PMID:27479514

Effect of Zn and Te beam intensity upon the film quality of ZnTe layers on severely lattice mismatched sapphire substrates by molecular beam epitaxy

NASA Astrophysics Data System (ADS)

Nakasu, Taizo; Sun, W.; Kobayashi, M.; Asahi, T.

2017-06-01

Zinc telluride layers were grown on highly-lattice-mismatched sapphire substrates by molecular beam epitaxy, and their crystallographic properties were studied by means of X-ray diffraction pole figures. The crystal quality of the ZnTe thin film was further studied by scanning electron microscopy, X-ray rocking curves and low-temperature photoluminescence measurements. These methods show that high-crystallinity (111)-oriented single domain ZnTe layers with the flat surface and good optical properties are realized when the beam intensity ratio of Zn and Te beams is adjusted. The migration of Zn and Te was inhibited by excess surface material and cracks were appeared. In particular, excess Te inhibited the formation of a high-crystallinity ZnTe film. The optical properties of the ZnTe layer revealed that the exciton-related features were dominant, and therefore the film quality was reasonably high even though the lattice constants and the crystal structures were severely mismatched.

Critical layer thickness in In/sub 0. 2/Ga/sub 0. 8/As/GaAs single strained quantum well structures

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fritz, I.J.; Gourley, P.L.; Dawson, L.R.

1987-09-28

We report accurate determination of the critical layer thickness (CLT) for single strained-layer epitaxy in the InGaAs/GaAs system. Our samples were molecular beam epitaxially grown, selectively doped, single quantum well structures comprising a strained In/sub 0.2/Ga/sub 0.8/As layer imbedded in GaAs. We determined the CLT by two sensitive techniques: Hall-effect measurements at 77 K and photoluminescence microscopy. Both techniques indicate a CLT of about 20 nm. This value is close to that determined previously (--15 nm) for comparable strained-layer superlattices, but considerably less than the value of --45 nm suggested by recent x-ray rocking-curve measurements. We show by a simplemore » calculation that photoluminescence microscopy is more than two orders of magnitude more sensitive to dislocations than x-ray diffraction. Our results re-emphasize the necessity of using high-sensitivity techniques for accurate determination of critical layer thicknesses.« less