Zeitschriftenartikel: „Synchrotron-based XRT“

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Yao, Yong Zhao, Yukari Ishikawa, Yoshihiro Sugawara, Koji Sato, Katsunori Danno, Takayuki Shirai, Kazuaki Sato et al. „Dislocations in SiC Revealed by NaOH Vapor Etching and a Comparison with X-Ray Topography Taken with Various g-Vectors“. Materials Science Forum 858 (Mai 2016): 389–92. http://dx.doi.org/10.4028/www.scientific.net/msf.858.389.

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Threading dislocations (TDs) in 4H-SiC have been studied by comparing etch pits formed by NaOH vapor etching with results of synchrotron monochromatic-beam X-ray topography (XRT) taken under different g-vectors. Burgers vectors determined based on XRT results were utilized to investigate the etch pit characteristics of edge (TED), screw (TSD) and mixed (Burgers vector b=c+a, TMD) threading dislocations. It has been found that pit formation by NaOH vapor etching was very different to that by conventional molten KOH etching. We discuss the possibility of using NaOH vapor etching to distinguish TMDs from TSDs, and report a variety of characteristic etch pits formed by this method and their correlations to dislocation behavior.

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Dalmau, Rafael, Jeffrey Britt, Hao Yang Fang, Balaji Raghothamachar, Michael Dudley und Raoul Schlesser. „X-Ray Topography Characterization of Large Diameter AlN Single Crystal Substrates“. Materials Science Forum 1004 (Juli 2020): 63–68. http://dx.doi.org/10.4028/www.scientific.net/msf.1004.63.

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Large diameter aluminum nitride (AlN) substrates, up to 50 mm, were manufactured from single crystal boules grown by physical vapor transport (PVT). Synchrotron-based x-ray topography (XRT) was used to characterize the density, distribution, and type of dislocations. White beam topography images acquired in transmission geometry were used to analyze basal plane dislocations (BPDs) and low angle grain boundaries (LAGBs), while monochromatic beam, grazing incidence images were used to analyze threading dislocations. Boule diameter expansion, without the introduction of LAGBs around the periphery, was shown. A 48 mm substrate with a uniform threading dislocation density below 7.0 x 102 cm-2 and a BPD of 0 cm-2, the lowest dislocation densities reported to date for an AlN single crystal this size, was demonstrated.

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Acciari, MAGIC Collaboration: V. A., S. Ansoldi, L. A. Antonelli, A. Arbet Engels, A. Babić, B. Banerjee, U. Barres de Almeida et al. „An intermittent extreme BL Lac: MWL study of 1ES 2344+514 in an enhanced state“. Monthly Notices of the Royal Astronomical Society 496, Nr. 3 (17.06.2020): 3912–28. http://dx.doi.org/10.1093/mnras/staa1702.

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ABSTRACT Extreme high-frequency BL Lacs (EHBL) feature their synchrotron peak of the broad-band spectral energy distribution (SED) at νs ≥ 1017 Hz. The BL Lac object 1ES 2344+514 was included in the EHBL family because of its impressive shift of the synchrotron peak in 1996. During the following years, the source appeared to be in a low state without showing any extreme behaviours. In 2016 August, 1ES 2344+514 was detected with the ground-based γ-ray telescope FACT during a high γ-ray state, triggering multiwavelength (MWL) observations. We studied the MWL light curves of 1ES 2344+514 during the 2016 flaring state, using data from radio to very-high-energy (VHE) γ-rays taken with OVRO, KAIT, KVA, NOT, some telescopes of the GASP-WEBT collaboration at the Teide, Crimean, and St. Petersburg observatories, Swift-UVOT, Swift-XRT, Fermi-LAT, FACT, and MAGIC. With simultaneous observations of the flare, we built the broad-band SED and studied it in the framework of a leptonic and a hadronic model. The VHE γ-ray observations show a flux level of 55 per cent of the Crab Nebula flux above 300 GeV, similar to the historical maximum of 1995. The combination of MAGIC and Fermi-LAT spectra provides an unprecedented characterization of the inverse-Compton peak for this object during a flaring episode. The Γ index of the intrinsic spectrum in the VHE γ-ray band is 2.04 ± 0.12stat ± 0.15sys. We find the source in an extreme state with a shift of the position of the synchrotron peak to frequencies above or equal to 1018 Hz.

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Smieska, Louisa M., Arthur R. Woll, Frederik Vanmeert und Koen Janssens. „Synchrotron-Based High-Energy X-ray MA-XRF and MA-XRD for Art and Archaeology“. Synchrotron Radiation News 32, Nr. 6 (02.11.2019): 29–33. http://dx.doi.org/10.1080/08940886.2019.1680212.

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Gorenstein, Paul. „Focusing X-Ray Optics for Astronomy“. X-Ray Optics and Instrumentation 2010 (27.12.2010): 1–19. http://dx.doi.org/10.1155/2010/109740.

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Focusing X-ray telescopes have been the most important factor in X-ray astronomy’s ascent to equality with optical and radio astronomy. They are the prime tool for studying thermal emission from very high temperature regions, non-thermal synchrotron radiation from very high energy particles in magnetic fields and inverse Compton scattering of lower energy photons into the X-ray band. Four missions with focusing grazing incidence X-ray telescopes based upon the Wolter 1 geometry are currently operating in space within the 0.2 to 10 keV band. Two observatory class missions have been operating since 1999 with both imaging capability and high resolution dispersive spectrometers. They are NASA’s Chandra X-ray Observatory, which has an angular resolution of 0.5 arc seconds and an area of 0.1 m2 and ESA’s XMM-Newton which has 3 co-aligned telescopes with a combined effective area of 0.43 m2 and a resolution of 15 arc seconds. The two others are Japan’s Suzaku with lower spatial resolution and non-dispersive spectroscopy and the XRT of Swift which observes and precisely positions the X-ray afterglows of gamma-ray bursts. New missions include focusing telescopes with much broader bandwidth and telescopes that will perform a new sky survey. NASA, ESA, and Japan’s space agency are collaborating in developing an observatory with very large effective area for very high energy resolution dispersive and non-dispersive spectroscopy. New technologies are required to improve upon the angular resolution of Chandra. Adaptive optics should provide modest improvement. However, orders of magnitude improvement can be achieved only by employing physical optics. Transmitting diffractive-refractive lenses are capable theoretically of achieving sub-milli arc second resolution. X-ray interferometry could in theory achieve 0.1 micro arc second resolution, which is sufficient to image the event horizon of super massive black holes at the center of nearby active galaxies. However, the physical optics systems have focal lengths in the range 103 to 104 km and cannot be realized until the technology for accurately positioned long distance formation flying between optics and detector is developed.

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Kim, Julie J., Florence T. Ling, Dan A. Plattenberger, Andres F. Clarens, Antonio Lanzirotti, Matthew Newville und Catherine A. Peters. „SMART mineral mapping: Synchrotron-based machine learning approach for 2D characterization with coupled micro XRF-XRD“. Computers & Geosciences 156 (November 2021): 104898. http://dx.doi.org/10.1016/j.cageo.2021.104898.

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Xia, Jin Lan, Hong Chang Liu, Zhen Yuan Nie, Hong Rui Zhu, Yun Yang, Lei Wang, Jian Jun Song et al. „Characterization of Microbe-Mineral Interfacial Interaction Based on Synchrotron Radiation Techniques“. Advanced Materials Research 1130 (November 2015): 123–26. http://dx.doi.org/10.4028/www.scientific.net/amr.1130.123.

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This article presents the progress on characterization of the interfacial interaction between sulfur oxidizing microbes and sulfide minerals by using of synchrotron radiation-based techniques including S/Fe/Cu X-ray absorption near-edge structure spectroscopy (XANES), X-ray Diffraction (XRD), micro-X-ray fluorescence (μ-XRF) mapping and micro-scanning transmission X-ray microscopy (μ-STXM) imaging, together with other accessory approaches such as SEM/EDS, Raman spectroscopy, FT-IR spectroscopy, and electrochemical methods as well as comparative proteomics methodology.

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Gonzalez, Victor, Annelies van Loon, Stephen WT Price, Petria Noble und Katrien Keune. „Synchrotron micro-XRD and micro-XRD-CT reveal newly formed lead–sulfur compounds in Old Master paintings“. Journal of Analytical Atomic Spectrometry 35, Nr. 10 (2020): 2267–73. http://dx.doi.org/10.1039/d0ja00169d.

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Garg, Alka B., P. Thangadurai, S. Meenakshi und S. Ramasamy. „Synchrotron based XRD study on nano crystalline SnO2under pressure“. Journal of Physics: Conference Series 377 (30.07.2012): 012022. http://dx.doi.org/10.1088/1742-6596/377/1/012022.

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Rao, D. V., G. E. Gigante, R. Cesareo, A. Brunetti, N. Schiavon, T. Akatsuka, T. Yuasa und T. Takeda. „Synchrotron-based XRD from rat bone of different age groups“. Materials Science and Engineering: C 74 (Mai 2017): 207–18. http://dx.doi.org/10.1016/j.msec.2016.11.136.

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Sedigh Rahimabadi, Pooria, Mehdi Khodaei und Kaveenga R. Koswattage. „Review on applications of synchrotron‐based X‐ray techniques in materials characterization“. X-Ray Spectrometry 49, Nr. 3 (März 2020): 348–73. http://dx.doi.org/10.1002/xrs.3141.

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Mitsi, E., und T. J. Mertzimekis. „RICOCHET: A quick-and-dirty approach to analyze μ-XRF synchrotron data using open-source utilities“. HNPS Proceedings 23 (08.03.2019): 162. http://dx.doi.org/10.12681/hnps.1897.

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A semi-automated procedure based on open-source utilities was designed and built to analyze spectra collected at a synchrotron accelerator using the μ-XRF technique. The software (RICOCHET) has a fast, efficient and user-friendly design aimed at performing online analysis. A few examples of its application using recent μ-XRF data from the SUL-X beamline at ANKA Synchrotron Facility (KIT) are presented.

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Vergucht, Eva, Toon Brans, Filip Beunis, Jan Garrevoet, Stephen Bauters, Maarten De Rijcke, David Deruytter et al. „Methodological challenges of optical tweezers-based X-ray fluorescence imaging of biological model organisms at synchrotron facilities“. Journal of Synchrotron Radiation 22, Nr. 4 (27.06.2015): 1096–105. http://dx.doi.org/10.1107/s1600577515009534.

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Recently, a radically new synchrotron radiation-based elemental imaging approach for the analysis of biological model organisms and single cells in their naturalin vivostate was introduced. The methodology combines optical tweezers (OT) technology for non-contact laser-based sample manipulation with synchrotron radiation confocal X-ray fluorescence (XRF) microimaging for the first time at ESRF-ID13. The optical manipulation possibilities and limitations of biological model organisms, the OT setup developments for XRF imaging and the confocal XRF-related challenges are reported. In general, the applicability of the OT-based setup is extended with the aim of introducing the OT XRF methodology in all research fields where highly sensitivein vivomulti-elemental analysis is of relevance at the (sub)micrometre spatial resolution level.

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Carbone, Cristina, Pietro Marescotti, Gabriella Lucchetti, Jean Cauzid und Emilie Chalmin. „Application of synchrotron radiation-based techniques (μ-XRD, μ-XRF, and μ-XANES) to study Fe-rich hardpans within waste-rock dump“. Neues Jahrbuch für Mineralogie - Abhandlungen 188, Nr. 1 (01.02.2011): 21–30. http://dx.doi.org/10.1127/0077-7757/2011/0191.

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Görner, W. „Dead-time correction of synchrotron radiation-based XRF measurements at decaying storage ring current“. X-Ray Spectrometry 34, Nr. 5 (2005): 432–34. http://dx.doi.org/10.1002/xrs.851.

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Rao, Donepudi V., Medasani Swapna, Roberto Cesareo, Antonio Brunetti, Tako Akatsuka, Tetsuya Yuasa, Tohoru Takeda und Giovanni E. Gigante. „Synchrotron-based scattered radiation from phantom materials used in X-ray CT“. Journal of X-Ray Science and Technology 18, Nr. 3 (2010): 327–37. http://dx.doi.org/10.3233/xst-2010-0255.

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Constantinescu, Bogdan, Roxana Bugoi, Emmanuel Pantos und Dragomir Popovici. „Phase and chemical composition analysis of pigments used in Cucuteni Neolithic painted ceramics“. Documenta Praehistorica 34 (31.12.2007): 281–88. http://dx.doi.org/10.4312/dp.34.21.

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Two analytical methods – 241Am-based X-Ray Fluorescence (XRF) and Synchrotron Radiation X-ray Diffraction (SR-XRD) – were used to investigate the elemental and mineralogical composition of pigments which decorate some Cucuteni Neolithic ceramic sherds. Local hematite and local calcite were the main components for red and white pigments, respectively. For black pigments, iron oxides (e.g. magnetite) were used. They were often mixed with manganese oxides (e.g. jacobsite), which originated from Iacobeni manganese minerals deposits on the Bistrita River. Taking into account the results of the experiments, several conclusions regarding manufacturing procedures employed, and potential trade routes during the Neolithic were drawn.

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Fatima, A., V. K. Kulkarni, N. R. Banda, A. K. Agrawal, B. Singh, P. S. Sarkar, S. Tripathi, T. Shripathi, Y. Kashyap und A. Sinha. „Non-destructive evaluation of teeth restored with different composite resins using synchrotron based micro-imaging“. Journal of X-Ray Science and Technology 24, Nr. 1 (01.03.2016): 119–32. http://dx.doi.org/10.3233/xst-160530.

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Xu, Wei, Zhiheng Du, Shiwei Liu, Yingcai Zhu, Cunde Xiao und Augusto Marcelli. „Perspectives of XRF and XANES Applications in Cryospheric Sciences Using Chinese SR Facilities“. Condensed Matter 3, Nr. 4 (08.10.2018): 29. http://dx.doi.org/10.3390/condmat3040029.

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As an important part of the climate system, the cryosphere, can be studied with a variety of techniques based on laboratory-based or field-portable equipment in order to accumulate data for a better understanding of this portion of the Earth’s surface. The advent of synchrotron radiation (SR) facilities as large scientific interdisciplinary infrastructures has reshaped the scenario of these investigations and, in particular, of condensed matters researches. Many spectroscopic methods allow for characterizing the structure or electronic structure of samples, while the scattering/diffraction methods enable the determination of crystalline structures of either organic or inorganic systems. Moreover, imaging methods offer an unprecedented spatial resolution of samples, revealing their inner structure and morphology. In this contribution, we briefly introduce the SR facilities now available in mainland China, and the perspectives of SR-based methods suitable to investigate ice, snow, aerosols, dust, and other samples of cryospheric origin from deep ice cores, permafrost, filters, etc. The goal is to deepen the understanding in cryospheric sciences through an increased collaboration between the synchrotron radiation community and the scientists working in polar areas or involved in correlated environmental problems.

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Hormes, Josef, Qunfeng Xiao, Yongfeng Hu, Christine Bläuer, Anja Diekamp, Jürg Goll und G. Lisa Bovenkamp. „Mortar samples from the Abbey of Saint John at Müstair: a combined spatially resolved X-ray fluorescence and X-ray absorption (XANES) study“. Journal of Analytical Atomic Spectrometry 30, Nr. 3 (2015): 702–6. http://dx.doi.org/10.1039/c4ja00401a.

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Rakovan, John, Yun Luo und Olaf Borkiewicz. „Synchrotron microanalytical methods in the study of trace and minor elements in apatite“. Mineralogia 39, Nr. 1-2 (01.01.2008): 31–40. http://dx.doi.org/10.2478/v10002-008-0001-9.

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Synchrotron microanalytical methods in the study of trace and minor elements in apatiteSynchrotron X-ray facilities have the capability for numerous microanalytical methods with spatial resolutions in the micron to submicron range and sensitivities as low as ppm to ppb. These capabilities are the result of a high X-ray brilliance (many orders of magnitude greater than standard tube and rotating anode sources); a continuous, or white, spectrum through the hard X-ray region; high degrees of X-ray columniation and polarization; and new developments in X-ray focusing methods. The high photon flux and pulsed nature of the source also allow for rapid data collection and high temporal resolution in certain experiments. Of particular interest to geoscientists are X-ray fluorescence microprobes which allow for numerous analytical techniques including X-ray fluorescence (XRF) analysis of trace element concentrations and distributions; X-ray absorption spectroscopy (XAS) for chemical speciation, structural and oxidation state information; X-ray diffraction (XRD) for phase identification; and fluorescence microtomography (CMT) for mapping the internal structure of porous or composite materials as well as elemental distributions (Newville et al. 1999; Sutton et al. 2002; Sutton et al. 2004).We have employed several synchrotron based microanalytical methods including XRF, microEXAFS (Extended X-ray Absorption Fine Structure), microXANES (X-ray Absorption Near Edge Structure) and CMT for the study of minor and trace elements in apatite (and other minerals). We have also been conducting time resolved X-ray diffraction to study nucleation of and phase transformations among precursor phases in the formation of apatite from solution at earth surface conditions. Summaries of these studies are given to exemplify the capabilities of synchrotron microanalytical techniques.

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Kayser, Y., D. Banaś, W. Cao, J. Cl Dousse, J. Hoszowska, P. Jagodziński, M. Kavčič et al. „Depth profiling of dopants implanted in Si using the synchrotron radiation based high-resolution grazing emission technique“. X-Ray Spectrometry 41, Nr. 2 (25.01.2012): 98–104. http://dx.doi.org/10.1002/xrs.2372.

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Ibrahim, Ahmed Hassan, Yehia Mohammed Abbas, Shehab Esmail Mohammed und Ahmed Bakry Mansour. „Investigation of Structural and Magnetic Properties of Multiferroic La1-Xyxfeo3perovskites, Prepared by Citrate Auto-Combustion Technique“. JOURNAL OF ADVANCES IN PHYSICS 15 (25.01.2019): 6056–77. http://dx.doi.org/10.24297/jap.v15i0.8056.

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In this work, we studied the structural and magnetic properties of multiferroic La1-xYxFeO3 perovskites, (x= 0.0, 0.05, 0.1, 0.15, 0.25 and 0.3) which synthesized through Sol-gel auto-combustion technique using a citric acid as a fuel. The room temperature synchrotron X-ray diffraction (XRD) analysis revealed that the all the synthesized samples consisted of the polycrystalline orthorhombic structure perovskites(space group pnma), and tolerance factor confirmed the phase stability of the prepared perovskite system.The Williamson-Hall plot based on synchrotron XRD data were employed to estimate the average particle diameter and varies from 18 nmto 27.8 nm.For a deeper insight of the crystal structure, high resolution transmission microscopy imaging (HRTEM) was performed. The estimated values of crystallite size from HRTEM and synchrotron XRD data were coincident. Many of crystallographic parameters and electron density measurements were calculated by Rietveld refinement of synchrotron XRD data. La1-xYxFeO3 perovskite crystalsarecanted antiferromagnets with a weak ferromagnetism in room temperature.The magnetic properties were gotten through analyzing the magnetization versus temperature M(T) and M(H) hysteresis loop which characterized by a vibrating sample magnetometer (VSM). The molecular structure showed the decrease of the tilting of the octahedra <FeO6> with increasing Y content trying to strengthen the ferromagnetic character. Selected Area Electron Diffraction (SAED) patterns of the investigated samples exhibited spotty ring patterns,confirming the polycrystalline character.The orthoferrite La1-xYxFeO3 crystalsare a promising candidate for optical device applications in broad temperature range and high power system.

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Lin, Yan-Ru, Chun-Yu Ho, Wei-Tsung Chuang, Ching-Shun Ku und Ji-Jung Kai. „Swelling of ion-irradiated 3C–SiC characterized by synchrotron radiation based XRD and TEM“. Journal of Nuclear Materials 455, Nr. 1-3 (Dezember 2014): 292–96. http://dx.doi.org/10.1016/j.jnucmat.2014.06.061.

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Rao, Donepudi V., Roberto Cesareo, Antonio Brunetti, Tako Akatsuka, Tetsuya Yuasa, Tohoru Takeda und Giovanni E. Gigante. „Embedded soft-tissue image mechanism of a small animal shell with synchrotron-based micro-CT“. Journal of X-Ray Science and Technology 20, Nr. 3 (2012): 291–99. http://dx.doi.org/10.3233/xst-2012-0338.

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Alfeld, M., K. Janssens, J. Dik, P. D. Siddons und E. van de Wetering. „F-68 Visualizing the 17th Century Underpainting Using Mobile and Synchrotron-Based Scanning Macro-XRF“. Powder Diffraction 25, Nr. 2 (Juni 2010): 219. http://dx.doi.org/10.1154/1.3455031.

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Song, Chulho, Kimihiko Ito, Osami Sakata und Yoshimi Kubo. „Operando structural study of non-aqueous Li–air batteries using synchrotron-based X-ray diffraction“. RSC Advances 8, Nr. 46 (2018): 26293–99. http://dx.doi.org/10.1039/c8ra04855j.

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The Li–O₂ electrochemical reaction involving the formation and decomposition of crystalline Li₂O₂ was clearly demonstrated by using an operando synchrotron-based XRD in a transmission mode and a special airtight LAB cell.

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Abbas, Yehia Mohammed, Shehab Esmail Mohammed Ali, Ahmed Bakry Mansour und Ahmed Hassan Ibrahim Abdel-Hamid. „Synthesis, structure and magnetic characterization of orthoferrite LaFeO3 nanoparticles“. JOURNAL OF ADVANCES IN PHYSICS 14, Nr. 3 (25.09.2018): 5664–81. http://dx.doi.org/10.24297/jap.v14i3.7693.

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Single-phase lanthanum orthoferrite (LaFeO3) was prepared by an auto-combustion method. The analysis of synchrotron room temperature X-ray diffraction (XRD) data confirmed the orthorhombic LaFeO3 perovskite of space group Pnma without any impurity phase. The Scherrer's formula and Williamson-Hall plot based on XRD data were employed to estimate the crystallite size of the prepared sample. For a deeper insight into the crystal structure, high-resolution transmission microscopy imaging (HRTEM) was performed. The estimated values of crystallite size from HRTEM and synchrotron XRD data were coincident. The HRTEM images confirmed the polycrystalline nature of the prepared sample through the obvious lattice planes which are related to (121) plane. Furthermore, the M(H) hysteresis loop of the investigated sample was characterized by a vibrating sample magnetometer (VSM). The magnetic properties obtained through analyzing the magnetization versus temperature M(T) and magnetization versus magnetic field M(H) curves indicated that LaFeO3 possessed weak ferromagnetism at room temperature.

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Wilson, A. S., K. A. Christofidou, A. Evans, M. C. Hardy und H. J. Stone. „Comparison of Methods for Quantification of Topologically Close-Packed Phases in Ni-Based Superalloys“. Metallurgical and Materials Transactions A 50, Nr. 12 (15.10.2019): 5925–34. http://dx.doi.org/10.1007/s11661-019-05442-3.

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Abstract The ability to quantify accurately the formation of topologically close-packed phases in nickel-based superalloys is key to assessing their thermal stability and ensuring that their performances will not deteriorate during long-term exposure at high temperatures. To investigate the effectiveness of synchrotron XRD for the detection of such minority phases in Ni-based superalloys, the commercial polycrystalline alloy RR1000 was analyzed following exposures of varying times at 800 °C. Data were collected from both solid samples and extracted residues, and additional laboratory X-ray diffraction was performed on the residues. The minor phases were successfully detected in solid samples using synchrotron radiation, and a comparison of the results from these quantification methods shows that the extraction method gives results of the right order of magnitude to reflect the phase quantities that are present in the alloy. However, the results indicate that the synchrotron route is not a suitable method for the quantification of phases present in quantities less than approximately 0.3 wt pct.

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Yang, Xiao-Qing, James McBreen, Won-Sub Yoon, Masaki Yoshio, Hongyu Wang, Kenji Fukuda und Tatsuo Umeno. „Structural studies of the new carbon-coated silicon anode materials using synchrotron-based in situ XRD“. Electrochemistry Communications 4, Nr. 11 (November 2002): 893–97. http://dx.doi.org/10.1016/s1388-2481(02)00483-6.

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Colston, Gerard, Stephen D. Rhead, Vishal Ajit Shah, Oliver J. Newell, Igor P. Dolbnya, David R. Leadley und Maksym Myronov. „Mapping the Strain State of 3C-SiC/Si (001) Suspended Structures Using μ-XRD“. Materials Science Forum 858 (Mai 2016): 274–77. http://dx.doi.org/10.4028/www.scientific.net/msf.858.274.

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The residual strain has been mapped across suspended 3C-SiC membranes and wires using synchrotron based micro X-ray diffraction (μ-XRD). Residual tensile strain is observed to relax slightly upon suspension in both sets of structures. Similar maps were acquired by calculating the residual strain from the shift in 3C-SiC Raman peaks. Comparable trends in strain relaxation are observed by both methods, although the sensitivity of μ-XRD is higher using our measurement conditions. While Raman shift provides a fast and convenient method for mapping strain variations, it cannot give direct measurements of the lattice parameters that can be achieved with μ-XRD, making these techniques excellent complimentary methods of mapping residual strain in 3C-SiC.

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Fancello, Dario, Jessica Scalco, Daniela Medas, Elisa Rodeghero, Annalisa Martucci, Carlo Meneghini und Giovanni De Giudici. „XRD-Thermal Combined Analyses: An Approach to Evaluate the Potential of Phytoremediation, Phytomining, and Biochar Production“. International Journal of Environmental Research and Public Health 16, Nr. 11 (04.06.2019): 1976. http://dx.doi.org/10.3390/ijerph16111976.

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A method for evaluating the potential of reuse of biomasses for economic purposes is here presented starting from a case study. Juncus acutus plants and rhizospheres were harvested from abandoned Zn–Pb mine areas of southwest Sardinia (Italy). Thermogravimetry and Differential Thermal analyses were performed to evaluate the temperatures at which significant reactions occur. X-ray Diffraction (XRD) analysis was carried out on raw samples and on samples heated ex-situ (by a conventional diffractometer) or in-situ (by synchrotron-based diffraction). Raw samples mainly consist of quartz, phyllosilicates, and feldspars with minor amounts of sulfides, sulfates, and Fe, Pb, and Zn carbonates, concentrated in the rhizosphere. After heating, Zn and Fe oxides and willemite are observed in internal roots and stems, revealing the presence of these metals in the plant tissues. In-situ heating was less effective than ex-situ in revealing minor phases in organic samples, probably because the scarcity of oxygen within the sample holder did not allow the degradation of organic compounds and the oxidation of sulfides, resulting in a low quality XRD signal even if obtained with the high resolution ensured by a synchrotron light source. This method can be applied to plants from polluted sites for metal exploitation, and/or to biomasses from unpolluted sites for biochar production, since both applications take advantage of the knowledge of the minerals formed after heating.

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Li, Runguang, Youkang Wang, Xiaojing Liu, Shilei Li, Qing Tan, Wenjun Liu, Xing Fang und Yan-Dong Wang. „Micromechanical behaviors related to confined deformation in pure titanium“. MATEC Web of Conferences 321 (2020): 12018. http://dx.doi.org/10.1051/matecconf/202032112018.

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Confined deformation, e.g. mechanical twinning, shear banding, and Lüders banding, etc. was extensively observed in metals and alloys with low stacking-fault energies, especially under complex loadings, governing the mechanical properties. It is often accompanied with gradient microstructures to accommodate the stress concentrations. Understanding the micromechanical behaviors of structural materials having confined deformation is important for evaluating the structural stabilities of engineering components. Synchrotron-based techniques provide powerful tools for multiscale microstructural characterization owing to their good resolution in real/reciprocal space, fast data collection/processing and flexible application scenarios. In this paper, the synchrotron-based high-energy X-ray diffraction (HE-XRD) and microdiffraction (μXRD) techniques in combination with traditional characterization methods are used to reveal the deformational gradient structures/stresses under different loading modes in multiscale. The structure/stress gradients induced by laser shot peening treatment and the deformation twins generated during uniaxial tensile loading in pure titanium were systematically studied by HE-XRD and μXRD, in order to elucidate the accommodating role of the deformational structures subjected to various confined scenarios. The new finding regarding the micromechanical behaviors related to confined deformation contributes to the in-depth understanding of related complex deformation behaviors.

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Rebuffi, Luca, Paolo Scardi und Manuel Sanchez del Rio. „Design and management of a powder diffraction beamline for Line Profile Analysis: a realistic ray-tracing approach“. Powder Diffraction 30, S1 (16.04.2015): S56—S64. http://dx.doi.org/10.1017/s0885715614001328.

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Most synchrotron radiation X-ray diffraction (XRD) beamlines have been primarily designed for studying conventional materials, whereas a modern approach to nanomaterials requires a complete control of the diffracted signal, and therefore of the optics and general setup of the beamline. This requirement is especially relevant when Line Profile Analysis is pushed to the limits of large domain sizes, small deformations, or low defects concentration, which is a driving force to use synchrotron radiation XRD. We combine the SHADOW ray-tracing optical simulation with the calculation of powder diffraction profile from standard materials, into a high-level workflow environment based on the ORANGE software. Algorithms are developed to reproduce optical elements in a realistic form, so to evaluate the effects of aberrations, with the final purpose of reconstructing the Instrumental Profile Function of the beamline, with the possibility of investigating the role of each separate element. The results of this work can be of interest to most beamlines as a powerful tool for the design of setups of existing as well as new beamlines.

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Clancy, Marie, Mark J. Styles, Colleen J. Bettles, Nick Birbilis, Justin A. Kimpton und Nathan A. S. Webster. „In situ XRD investigation of the evolution of surface layers on Pb-alloy anodes“. Powder Diffraction 32, S2 (22.08.2017): S54—S60. http://dx.doi.org/10.1017/s0885715617000793.

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The electrochemical behaviour of a number of Pb-based anode alloys, under simulated electrowinning conditions, in a 1.6 M H2SO4 electrolyte at 45 °C was studied. Namely, the evolution of PbO2 and PbSO4 surface layers was investigated by quantitative in situ synchrotron X-ray diffraction (S-XRD) and subsequent Rietveld-based quantitative phase analysis (QPA). In the context of seeking new anode alloys, this research shows that the industry standard Pb-0.08Ca-1.52Sn (wt%) anode, when exposed to a galvanostatic current and intermittent power interruptions, exhibited poor electrochemical performance relative to select custom Pb-based binary alloys; Pb–0.73Mg, Pb–5.05Ag, Pb–0.07Rh, and Pb–1.4Zn (wt%). The in situ S-XRD measurements and subsequent QPA indicated that this was linked to a lower proportion of β-PbO2, relative to PbSO4, on the Pb-0.08Ca-1.52Sn alloy at all stages of the electrochemical cycling. The best performing alloy, in terms of minimisation of overpotential during normal electrowinning operation and minimising the deleterious effects of repeated power interruptions – both of which are significant factors in energy consumption – was determined to be Pb–0.07Rh.

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Liu, Chenglin, Xiaohua Wang, Qiang Zhang, Dongliang Chen und Juncai Dong. „Studies on Location of Acupoints with X-ray Fluorescence Analysis Based on Synchrotron Radiation“. Journal of Medical Imaging and Health Informatics 11, Nr. 8 (01.08.2021): 2178–83. http://dx.doi.org/10.1166/jmihi.2021.3766.

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Acupuncture and moxibustion are commonly accepted treatments in traditional Chinese medicine (TCM). One of the important issues of interest is determining the accurate location of acupoints in acupuncture. Modern hightechnology methods were utilized to verify the accuracy of acupoint positions in TCM, reducing the uncertainty of manually locating the positions. The acupoint location was established according to the richness of trace elements (TEs). The relative content of TEs was perceived by X-ray fluorescence (XRF) analysis. The distribution of TEs was determined after the dates were calibrated and the processes were optimized. The relative content of TEs was significantly different in acupoint and non-acupoint areas. There was an uneven distribution of calcium, iron, copper, and zinc in the sample. The relative content of these elements was increased in the acupuncture areas, and the standard deviation was also relatively large, especially for calcium, showing obvious enrichment. According to the enriched area of the TEs, the distance was about 6 mm between the conception channel and the kidney meridian, and the distance to the stomach meridian was about 23 mm for the rabbit sample. The position of the acupoints and spacing of meridians, which were determined according to the enrichment of TEs, were consistent with the TCM theory. The results show that synchrotron radiation-based XRF is a suitable method for determining the location of acupoints.

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Mistry, Dharmica A. H., Joseph Haklani und Peter W. French. „Identification of Breast Cancer-Associated Lipids in Scalp Hair“. Breast Cancer: Basic and Clinical Research 6 (Januar 2012): BCBCR.S9607. http://dx.doi.org/10.4137/bcbcr.s9607.

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A correlation between the presence of breast cancer and a change in the synchrotron-generated X-ray diffraction (XRD) pattern of hair has been reported in several publications by different groups, and on average XRD-based assays detect around 75% of breast cancer patients in blinded studies. To date, the molecular mechanisms leading to this alteration are largely unknown. We have determined that the alteration is likely to be due to the presence of one or more breast cancer-associated phospholipids. Further characterization of these lipids could be used to develop a novel, sensitive and specific screening test for breast cancer, based on hair initially, and potentially extendable to other biological samples.

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Yang, Xiao-Qing, James McBreen, Won-Sub Yoon und Clare P. Grey. „Crystal structure changes of LiMn0.5Ni0.5O2 cathode materials during charge and discharge studied by synchrotron based in situ XRD“. Electrochemistry Communications 4, Nr. 8 (August 2002): 649–54. http://dx.doi.org/10.1016/s1388-2481(02)00406-x.

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Salvadó, Nati, Salvador Butí, Miguel A. G. Aranda und Trinitat Pradell. „New insights on blue pigments used in 15th century paintings by synchrotron radiation-based micro-FTIR and XRD“. Analytical Methods 6, Nr. 11 (2014): 3610. http://dx.doi.org/10.1039/c4ay00424h.

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Takagi, Sota, Kouhei Ichiyanagi, Atsushi Kyono, Shunsuke Nozawa, Nobuaki Kawai, Ryo Fukaya, Nobumasa Funamori und Shin-ichi Adachi. „Development of shock-dynamics study with synchrotron-based time-resolved X-ray diffraction using an Nd:glass laser system“. Journal of Synchrotron Radiation 27, Nr. 2 (27.01.2020): 371–77. http://dx.doi.org/10.1107/s1600577519016084.

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The combination of high-power laser and synchrotron X-ray pulses allows us to observe material responses under shock compression and release states at the crystal structure on a nanosecond time scale. A higher-power Nd:glass laser system for laser shock experiments was installed as a shock driving source at the NW14A beamline of PF-AR, KEK, Japan. It had a maximum pulse energy of 16 J, a pulse duration of 12 ns and a flat-top intensity profile on the target position. The shock-induced deformation dynamics of polycrystalline aluminium was investigated using synchrotron-based time-resolved X-ray diffraction (XRD) under laser-induced shock. The shock pressure reached up to about 17 GPa with a strain rate of at least 4.6 × 107 s–1 and remained there for nanoseconds. The plastic deformation caused by the shock-wave loading led to crystallite fragmentation. The preferred orientation of the polycrystalline aluminium remained essentially unchanged during the shock compression and release processes in this strain rate. The newly established time-resolved XRD experimental system can provide useful information for understanding the complex dynamic compression and release behaviors.

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Webster, Nathan A. S., Mark I. Pownceby, Ian C. Madsen, Andrew J. Studer und Justin A. Kimpton. „In situ diffraction studies of iron ore sinter bonding phase formation: QPA considerations and pushing the limits of laboratory data collection“. Powder Diffraction 29, S1 (17.11.2014): S54—S58. http://dx.doi.org/10.1017/s088571561400092x.

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The formation and decomposition of silico-ferrite of calcium and aluminium (SFCA) and SFCA-I iron ore sinter bonding phases have been investigated using in situ synchrotron and laboratory X-ray diffraction (XRD) and neutron diffraction (ND). An external standard approach for determining absolute phase concentrations via Rietveld refinement-based quantitative phase analysis is discussed. The complementarity of in situ XRD and ND in characterising sinter phase formation and decomposition is also shown, with the volume diffraction afforded by the neutron technique reducing errors in the quantification of magnetite above ~1200 °C. Finally, by collecting 6 s laboratory XRD datasets and using a heating rate of 175 °C min−1, phase formation and decomposition have been monitored under heating rates more closely approximating those encountered in industrial iron ore sintering.

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Nie, Zhenyuan, Weiwei Zhang, Hongchang Liu, Jinlan Xia, Wei Zhu, Duorui Zhang, Lei Zheng, Chenyan Ma, Yidong Zhao und Wen Wen. „Synchrotron Radiation Based Study of the Catalytic Mechanism of Ag+ to Chalcopyrite Bioleaching by Mesophilic and Thermophilic Cultures“. Minerals 8, Nr. 9 (03.09.2018): 382. http://dx.doi.org/10.3390/min8090382.

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The catalytic mechanism of Ag+ for chalcopyrite bioleaching by mesophilic culture (at 30 °C) and thermophilic culture (at 48 °C) was investigated using synchrotron radiation-based X-ray diffraction (SR-XRD) and S K-edge and Fe L-edge X-ray absorption near edge structure (XANES) spectroscopy. Bioleaching experiments showed that copper extraction from chalcopyrite bioleaching by both cultures was promoted significantly by Ag+, with more serious corrosion occurring on the minerals surface. SR-XRD and XANES analyses showed that the intermediates S0, jarosite and secondary minerals (bornite, chalcocite and covellite) formed for all bioleaching experiments. For these secondary minerals, the formation of bornite and covellite was promoted significantly in the presence of Ag+ for both cultures, while Ag+ has almost no effect on the formation of chalcocite. These results provided insight into the catalytic mechanisms of Ag+ to chalcopyrite bioleaching by the mesophilic and thermophilic cultures, which are both probably due to the rapid formation of bornite by Ag+ and the conversion of bornite to covellite.

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Wang, Xiaodong, Robert D. Hart, Jian Li, Robbie G. McDonald und Arie van Riessen. „Quantitative analysis of turbostratically disordered nontronite with a supercell model calibrated by the PONKCS method“. Journal of Applied Crystallography 45, Nr. 6 (15.11.2012): 1295–302. http://dx.doi.org/10.1107/s0021889812040484.

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Two calibration-based quantitative X-ray diffraction (XRD) models for turbostratically disordered Bulong nontronite, the PONKCS (partial or no known crystal structure) approach and the supercell structural model, were compared in terms of the accuracy and refinement error from Rietveld quantitative phase analysis. The PONKCS approach achieved improved nontronite quantitative results with synchrotron diffraction patterns compared with those achieved with laboratory XRD data as a result of better data quality and the use of Debye–Scherrer geometry with significantly reduced preferred orientation effects. The introduction of a peak shape modifier (spherical harmonics) to correct the quantification result is mainly useful for laboratory XRD patterns containing nontronite collected from Bragg–Brentano geometry with appreciable preferred orientation effects. A novel calibration approach for the nontronite supercell model was developed, based on the Rietveld quantitative formula in theTOPASsymbolic computation system. The calibrated supercell model achieved better accuracy (deviation within 1 wt%) and lower refinement error than the PONKCS approach because the physically based description of turbostratic disorder requires fewer refinable parameters than the PONKCS approach. The drawbacks and limitations of the supercell approach are also discussed.

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Richard, A., N. Bukowiecki, P. Lienemann, M. Furger, M. Fierz, M. C. Minguillón, B. Weideli et al. „Quantitative sampling and analysis of trace elements in atmospheric aerosols: impactor characterization and Synchrotron-XRF mass calibration“. Atmospheric Measurement Techniques 3, Nr. 5 (20.10.2010): 1473–85. http://dx.doi.org/10.5194/amt-3-1473-2010.

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Abstract. Identification of trace elements in ambient air can add substantial information to pollution source apportionment studies, although they do not contribute significantly to emissions in terms of mass. A method for quantitative size and time-resolved trace element evaluation in ambient aerosols with a rotating drum impactor and synchrotron radiation based X-ray fluorescence is presented. The impactor collection efficiency curves and size segregation characteristics were investigated in an experiment with oil and salt particles. Cutoff diameters were determined through the ratio of size distributions measured with two particle sizers. Furthermore, an external calibration technique to empirically link fluorescence intensities to ambient concentrations was developed. Solutions of elemental standards were applied with an ink-jet printer on thin films and area concentrations were subsequently evaluated with external wet chemical methods. These customized and reusable reference standards enable quantification of different data sets analyzed under varying experimental conditions.

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Richard, A., N. Bukowiecki, P. Lienemann, M. Furger, B. Weideli, M. Fierz, M. C. Minguillón et al. „Quantitative sampling and analysis of trace elements in ambient air: impactor characterization and Synchrotron-XRF mass calibration“. Atmospheric Measurement Techniques Discussions 3, Nr. 3 (01.06.2010): 2477–513. http://dx.doi.org/10.5194/amtd-3-2477-2010.

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Abstract. Identification of trace elements in ambient air can add substantial information to pollution source apportionment studies, although they do not contribute significantly to emissions in terms of mass. A method for quantitative size and time-resolved trace element evaluation in ambient aerosols with a rotating drum impactor and synchrotron radiation based X-ray fluorescence is presented. The impactor collection efficiency curves and size segregation characteristics were investigated in an experiment with oil and salt particles. Cutoff diameters were determined through the ratio of size distributions measured with two particles sizers. Furthermore, an external calibration technique to empirically link fluorescence intensities to ambient concentrations was developed. Solutions of elemental standards were applied with an ink-jet printer on thin films and area concentrations were subsequently evaluated with external wet chemical methods. These customized and reusable reference standards enable quantification of different data sets analyzed under varying experimental conditions.

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Bielewski, Marek, Jerome Himbert, Nedialka Niagolova, Gerald Falkenberg, Mats Eriksson und Maria Betti. „Nondestructive Spectrometric Study on a Radioactive Particle Embedded in a Marine Sediment“. Microscopy and Microanalysis 14, Nr. 4 (04.07.2008): 321–27. http://dx.doi.org/10.1017/s1431927608080707.

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A radioactive particle embedded in a sediment collected from the Irish Sea was examined with spectrometric methods to understand the potential bioavailability of its constituents. Images of the particle surface were acquired in the backscattering mode by scanning electron microscopy. The elemental composition of the particle surface layer was measured using energy dispersive (SEM-EDX) and wavelength dispersive (SEM-WDX) X-ray spectrometers. The investigation showed that the sample consists of a calcite matrix in which uranium is present in the form of separate inclusions. The diameter of U inclusions was less than 10 μm. Synchrotron radiation based X-ray fluorescence in confocal geometry (confocal μ-XRF) was used to determine the spatial distribution of elements in the particle. Three-dimensional reconstructions of the Ca, Cr, Mn, Fe, Zn, Sr, Ba, Pb, and U distributions were performed. The oxidation state of uranium in the different inclusions was determined by synchrotron radiation based X-ray absorption in confocal geometry (confocal μ-XANES). The isotopic composition of uranium was measured by secondary ion mass spectrometry. The results revealed that uranium was depleted in 235U. Pu and other actinides were not detected.

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Feret, Frank R. „Selected applications of Rietveld-XRD analysis for raw materials of the aluminum industry“. Powder Diffraction 28, Nr. 2 (02.05.2013): 112–23. http://dx.doi.org/10.1017/s088571561300016x.

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In the last few decades, X-ray diffraction (XRD) systems have been paramount and irreplaceable in controlling bauxite exploration, as well as Bayer and reduction processes. XRD quantitative phase analysis in the aluminum industry witnessed a steady deployment of the Rietveld method, which at present progressively replaces existing methodologies in research and plant laboratories. Rietveld analysis not only helped to surpass traditional XRD calibration methods, it also opened the door for new applications previously not possible. The use of the Rietveld method to characterize selected materials unique to the aluminum industry, such as bauxite, red mud, and alumina is demonstrated and discussed. This paper also presents how synchrotron-based diffractograms obtained for bauxite and red mud samples allowed a much better understanding of mineralogical representation, and made it possible to leverage their Rietveld quantification. Despite clear advantages, the Rietveld method also has limitations that are revealed. For alumina phase quantification, a dedicated Rietveld analytical program was built with structure data for eight alumina mineralogical phases: alpha, beta (β-Al2O3 = Na2O•11Al2O3), delta, gamma (2), kappa, sigma, and theta. The paper gives unique examples of phase quantification in aluminas of various origins and phase composition.

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Ahmed, S., M. Hackett, S. Caine, N. Sylvain, H. Hou, S. Weese Maley und ME Kelly. „P.061 Multi-modal synchrotron imaging techniques to quantify elemental and molecular changes after stroke in an animal model“. Canadian Journal of Neurological Sciences / Journal Canadien des Sciences Neurologiques 43, S2 (Juni 2016): S35. http://dx.doi.org/10.1017/cjn.2016.165.

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Background: Effects of stroke at the cellular and sub-cellular level remain poorly understood by conventional techniques. We use synchrotron-based imaging techniques to study elemental and biochemical changes in the infarct and penumbra after stroke in an experimental model. Methods: Ischemic stroke is induced in mice using the previously validated photothrombotic model. Animals are sacrificed at various time-points after stroke. Fourier transform infrared spectroscopic imaging (FTIRI) is used to gather sub-cellular (<1 µm spatial resolution) imaging data of lipid oxidation and protein aggregation in the areas of interest. X-ray fluorescence (XRF) imaging is used to image the distribution of bio-important elements at the cellular and sub-cellular spatial resolutions. Routine histology and immunohistochemistry are used to co-localize cell-types to areas of interest. Results: Preliminary XRF results indicate significant reduction in the concentration of multiple elements in the infarct, compared to the penumbra, at day 1 post-stroke. Some elements begin to return to normal concentration in the penumbra at day 3. FTIRI data shows that lipid and total protein levels decrease, while aggregate protein levels increase in the penumbra. Conclusions: Multi-modality synchrotron imaging can be used to map elements as well as bio-molecules in a stroke model. A better understanding of these changes can guide therapeutic interventions after stroke.

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Belissont, Rémi, Manuel Munoz, Marie-Christine Boiron, Béatrice Luais und Olivier Mathon. „Germanium Crystal Chemistry in Cu-Bearing Sulfides from Micro-XRF Mapping and Micro-XANES Spectroscopy“. Minerals 9, Nr. 4 (12.04.2019): 227. http://dx.doi.org/10.3390/min9040227.

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Germanium is considered a critical element, with a demand that has sharply increased due to booming high-technology industries. To understand Ge incorporation mechanisms in natural systems, we investigate Ge speciation in Cu-bearing sulfide minerals using synchrotron X-ray fluorescence (XRF) chemical mapping and Ge K-edge µ-X-ray absorption near-edge structures (µ-XANES) spectroscopy. The samples investigated include (i) a homogeneous chalcopyrite from the Kipushi polymetallic deposit (Central African copperbelt, D.R. Congo) and (ii) a zoned Ge-rich chalcopyrite from the Barrigão Cu deposit (Iberian pyrite belt, Portugal). First, our spectroscopic analysis supports the occurrence of tetrahedrally-coordinated Ge4+ in chalcopyrite, independently from origins or zoning patterns observed for these minerals. Then, based on statistical analyses of XRF chemical maps, we demonstrate that tetravalent germanium most likely incorporates chalcopyrite through the Fe crystallographic site via coupled substitutions with the following form: (2x + 3y)Fe3+ ⟷ (x + 2y)(Ge,Sn)4+ + x(Zn,Pb)2+ + y(Cu,Ag)+, although the presence of lattice vacancies cannot be completely excluded.

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Gherase, Mihai R., und David E. B. Fleming. „Probing Trace Elements in Human Tissues with Synchrotron Radiation“. Crystals 10, Nr. 1 (27.12.2019): 12. http://dx.doi.org/10.3390/cryst10010012.

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For the past several decades, synchrotron radiation has been extensively used to measure the spatial distribution and chemical affinity of elements found in trace concentrations (<few µg/g) in animal and human tissues. Intense and highly focused (lateral size of several micrometers) X-ray beams combined with small steps of photon energy tuning (2–3 eV) of synchrotron radiation allowed X-ray fluorescence (XRF) and X-ray absorption spectroscopy (XAS) techniques to nondestructively and simultaneously detect trace elements as well as identify their chemical affinity and speciation in situ, respectively. Although limited by measurement time and radiation damage to the tissue, these techniques are commonly used to obtain two-dimensional and three-dimensional maps of several elements at synchrotron facilities around the world. The spatial distribution and chemistry of the trace elements obtained is then correlated to the targeted anatomical structures and to the biological functions (normal or pathological). For example, synchrotron-based in vitro studies of various human tissues showed significant differences between the normal and pathological distributions of metallic trace elements such as iron, zinc, copper, and lead in relation to human diseases ranging from Parkinson’s disease and cancer to osteoporosis and osteoarthritis. Current research effort is aimed at not only measuring the abnormal elemental distributions associated with various diseases, but also indicate or discover possible biological mechanisms that could explain such observations. While a number of studies confirmed and strengthened previous knowledge, others revealed or suggested new possible roles of trace elements or provided a more accurate spatial distribution in relation to the underlying histology. This area of research is at the intersection of several current fundamental and applied scientific inquiries such as metabolomics, medicine, biochemistry, toxicology, food science, health physics, and environmental and public health.

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