Relevant bibliographies by topics / XAS spectroscopy

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  1. Journal articles
  2. Dissertations / Theses
  3. Books
  4. Book chapters
  5. Conference papers
  6. Reports

Academic literature on the topic 'XAS spectroscopy'

Author: Grafiati
Published: 4 June 2021
Last updated: 7 February 2022

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Journal articles on the topic "XAS spectroscopy"

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Sarangi, Ritimukta. "A biological perspective towards a standard for information exchange and reporting in XAS." Journal of Synchrotron Radiation 25, no. 4 (June 27, 2018): 944–52. http://dx.doi.org/10.1107/s1600577518008779.

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The complex structural landscape of biological samples and their sensitivity to X-ray exposure leads to specific challenges in biological X-ray absorption spectroscopy (bio-XAS) research, which in turn has necessitated standardization of various aspects of bio-XAS data measurement, analysis and interpretation. The bio-XAS community is therefore well suited for the development of a data-reporting standard with the specific aim of creating a feedback loop for improving/standardizing data analysis protocols and optionally to make published data available to collaborators/researchers in a meaningful and quantitative format. The XIF (XAFS information file) reporting format presented here contains key experimental and analysis parameters, useful in developing a consistent platform for bio-XAS research worldwide. Such a reporting standard, enforced by the user community and publishing groups alike, can be an important step towards the standardization of data measurement and analysis techniques in bio-XAS.
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Fracchia, Martina, Paolo Ghigna, Alberto Vertova, Sandra Rondinini, and Alessandro Minguzzi. "Time-Resolved X-ray Absorption Spectroscopy in (Photo)Electrochemistry." Surfaces 1, no. 1 (December 5, 2018): 138–50. http://dx.doi.org/10.3390/surfaces1010011.

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This minireview aims at providing a complete survey concerning the use of X-ray absorption spectroscopy (XAS) for time-resolved studies of electrochemical and photoelectrochemical phenomena. We will see that time resolution can range from the femto-picosecond to the second (or more) scale and that this joins the valuable throughput typical of XAS, which allows for determining the oxidation state of the investigated element, together with its local structure. We will analyze four different techniques that use different approaches to exploit the in real time capabilities of XAS. These are quick-XAS, energy dispersive XAS, pump & probe XAS and fixed-energy X-ray absorption voltammetry. In the conclusions, we will analyze possible future perspectives for these techniques.
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Chantler, Christopher T., M. Tauhidul Islam, Stephen P. Best, Lachlan J. Tantau, Chanh Q. Tran, Mun Hon Cheah, and Andrew T. Payne. "High-accuracy X-ray absorption spectra from mMsolutions of nickel (II) complexes with multiple solutions using transmission XAS." Journal of Synchrotron Radiation 22, no. 4 (June 19, 2015): 1008–21. http://dx.doi.org/10.1107/s1600577515006190.

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A new approach is introduced for determining X-ray absorption spectroscopy (XAS) spectra on absolute and relative scales using multiple solutions with different concentrations by the characterization and correction of experimental systematics. This hybrid technique is a development of standard X-ray absorption fine structure (XAFS) along the lines of the high-accuracy X-ray extended range technique (XERT) but with applicability to solutions, dilute systems and cold cell environments. This methodology has been applied to determining absolute XAS of bis(N-n-propyl-salicylaldiminato) nickel(II) and bis(N-i-propyl-salicylaldiminato) nickel(II) complexes with square planar and tetrahedral structures in 15 mMand 1.5 mMdilute solutions. It is demonstrated that transmission XAS from dilute systems can provide excellent X-ray absorption near-edge structure (XANES) and XAFS spectra, and that transmission measurements can provide accurate measurement of subtle differences including coordination geometries. For the first time, (transmission) XAS of the isomers have been determined from low-concentration solutions on an absolute scale with a 1–5% accuracy, and with relative precision of 0.1% to 0.2% in the active XANES and XAFS regions after inclusion of systematic corrections.
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Tamenori, Yusuke. "Electron yield soft X-ray photoabsorption spectroscopy under normal ambient-pressure conditions." Journal of Synchrotron Radiation 20, no. 3 (March 16, 2013): 419–25. http://dx.doi.org/10.1107/s0909049513003592.

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Ambient-pressure soft X-ray photoabsorption spectroscopy (XAS) was demonstrated to be applicable to the chemical analysis of hydrated transition-metal compounds. For this purpose, even under ambient-pressure conditions, electron yield detection XAS (EY-XAS), based on a simple drain-current set-up, was used to overcome a weakness in fluorescence yield detection XAS (FY-XAS), which does not give a pure soft XAS. The feasibility of EY-XAS was investigated and it was clarified that the EY-XAS under ambient-pressure conditions corresponds to the mixed data of the total EY and conversion EY spectra. Normal ambient-pressure EY-XAS analysis was applied to anhydrous (CoCl2) and to hydrated (CoCl2·6H2O) cobalt chloride at the CoL23-edge. The present measurements demonstrated the ability to unambiguously distinguish the different chemical states of cobalt ions, relying upon spectral differences that indicate octahedral/quasi-octahedral structural changes as a result of hydration/dehydration reactions.
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Martini, Andrea, and Elisa Borfecchia. "Spectral Decomposition of X-ray Absorption Spectroscopy Datasets: Methods and Applications." Crystals 10, no. 8 (August 1, 2020): 664. http://dx.doi.org/10.3390/cryst10080664.

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X-ray absorption spectroscopy (XAS) today represents a widespread and powerful technique, able to monitor complex systems under in situ and operando conditions, while external variables, such us sampling time, sample temperature or even beam position over the analysed sample, are varied. X-ray absorption spectroscopy is an element-selective but bulk-averaging technique. Each measured XAS spectrum can be seen as an average signal arising from all the absorber-containing species/configurations present in the sample under study. The acquired XAS data are thus represented by a spectroscopic mixture composed of superimposed spectral profiles associated to well-defined components, characterised by concentration values evolving in the course of the experiment. The decomposition of an experimental XAS dataset in a set of pure spectral and concentration values is a typical example of an inverse problem and it goes, usually, under the name of multivariate curve resolution (MCR). In the present work, we present an overview on the major techniques developed to realize the MCR decomposition together with a selection of related results, with an emphasis on applications in catalysis. Therein, we will highlight the great potential of these methods which are imposing as an essential tool for quantitative analysis of large XAS datasets as well as the directions for further development in synergy with the continuous instrumental progresses at synchrotron sources.
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Ewels, Philip, Thierry Sikora, Virginie Serin, Chris P. Ewels, and Luc Lajaunie. "A Complete Overhaul of the Electron Energy-Loss Spectroscopy and X-Ray Absorption Spectroscopy Database: eelsdb.eu." Microscopy and Microanalysis 22, no. 3 (February 22, 2016): 717–24. http://dx.doi.org/10.1017/s1431927616000179.

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AbstractThe electron energy-loss spectroscopy (EELS) and X-ray absorption spectroscopy (XAS) database has been completely rewritten, with an improved design, user interface, and a number of new tools. The database is accessible at https://eelsdb.eu/ and can now be used without registration. The submission process has been streamlined to encourage spectrum submissions and the new design gives greater emphasis on contributors’ original work by highlighting their papers. With numerous new filters and a powerful search function, it is now simple to explore the database of several hundred EELS and XAS spectra. Interactive plots allow spectra to be overlaid, facilitating online comparison. An application-programming interface has been created, allowing external tools and software to easily access the information held within the database. In addition to the database itself, users can post and manage job adverts and read the latest news and events regarding the EELS and XAS communities. In accordance with the ongoing drive toward open access data increasingly demanded by funding bodies, the database will facilitate open access data sharing of EELS and XAS spectra.
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Uehara, Akihiro, Toshiyuki Fujii, Hajimu Yamana, and Yoshihiro Okamoto. "An in-situ X-ray absorption spectroelectrochemical study of the electroreduction of uranium ions in HCl, HNO3, and Na2CO3 solutions." Radiochimica Acta 104, no. 1 (January 28, 2016): 1–9. http://dx.doi.org/10.1515/ract-2015-2436.

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MATSUSHITA, TOMOHIRA, MASAICHIRO MIZUMAKI, NAOSHI IKEDA, MAKOTO NAKAZAWA, AKANE AGUI, YUJI SAITOH, TAKESHI NAKATANI, AKITAKA YOSHIGOE, and SHIN NAKAMURA. "X-RAY ABSORPTION SPECTROSCOPY IN NaCo2O4, LaCoO3andSrCoO3." Surface Review and Letters 09, no. 02 (April 2002): 1327–31. http://dx.doi.org/10.1142/s0218625x02003755.

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We have performed Co 2p X-ray absorption spectroscopy (XAS) on a mixed valence hexagonal layered system NaCo 2 O 4, which shows large thermopower and metallic conductivity. We also measured XAS for SrCoO 3 and LaCoO 3 as examples of typical Co ionic states. The Co ions of the last two materials are octahedrally surrounded by oxygen atoms. A Co atom in NaCo 2 O 4 also has octahedral coordination with oxygen atoms but it is distorted slightly. The Co ions in SrCoO 3 and LaCoO 3 are in the d5 and d6 configuration respectively. The spectrum of NaCo 2 O 4 resembles that of LaCoO 3 rather than that of SrCoO 3; the Co ions in NaCo 2 O 4 can be regarded as the d6 configuration. Also, we have tried to calculate the XAS spectra by using the charge-transfer multiplet model (CT-M). Although we could not find out the best-fitting parameters, the results suggested the itinerancy of the Co 3d states.
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De Santis, Emiliano, Emma Shardlow, Francesco Stellato, Olivier Proux, Giancarlo Rossi, Christopher Exley, and Silvia Morante. "X-Ray Absorption Spectroscopy Measurements of Cu-ProIAPP Complexes at Physiological Concentrations." Condensed Matter 4, no. 1 (January 18, 2019): 13. http://dx.doi.org/10.3390/condmat4010013.

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The amyloidogenic islet amyloid polypeptide (IAPP) and the associated pro-peptide ProIAPP1–48 are involved in cell death in type 2 diabetes mellitus. It has been observed that interactions of this peptide with metal ions have an impact on the cytotoxicity of the peptides as well as on their deposition in the form of amyloid fibrils. In particular, Cu(II) seems to inhibit amyloid fibril formation, thus suggesting that Cu homeostasis imbalance may be involved in the pathogenesis of type 2 diabetes mellitus. We performed X-ray Absorption Spectroscopy (XAS) measurements of Cu(II)-ProIAPP complexes under near-physiological (10 μM), equimolar concentrations of Cu(II) and peptide. Such low concentrations were made accessible to XAS measurements owing to the use of the High Energy Resolved Fluorescence Detection XAS facility recently installed at the ESRF beamline BM16 (FAME-UHD). Our preliminary data show that XAS measurements at micromolar concentrations are feasible and confirm that ProIAPP1–48-Cu(II) binding at near-physiological conditions can be detected.
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Firet, Nienke J., Thomas Burdyny, Nathan T. Nesbitt, Sanjana Chandrashekar, Alessandro Longo, and Wilson A. Smith. "Copper and silver gas diffusion electrodes performing CO2 reduction studied through operando X-ray absorption spectroscopy." Catalysis Science & Technology 10, no. 17 (2020): 5870–85. http://dx.doi.org/10.1039/d0cy01267j.

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Dissertations / Theses on the topic "XAS spectroscopy"

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Adams, Stephen J. A. "Optical spectroscopy of InxGa1-xAs/GaAs quantum wells." Thesis, Heriot-Watt University, 1992. http://hdl.handle.net/10399/816.

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Wittee, Lopes Christian. "Characterization of metallic species on porous materials by in situ XAS." Doctoral thesis, Universitat Politècnica de València, 2018. http://hdl.handle.net/10251/107953.

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El objetivo de esta tesis es estudiar la agrupación y el crecimiento de especies metálicas confinadas o soportadas en materiales porosos mediante espectroscopia de absorción de rayos X in situ. Para lograrlo, las especies de paladio y plata se han introducido en materiales porosos (¿-alúmina, carbón activo y zeolitas) mediante impregnación vía húmeda y métodos de intercambio iónico, respectivamente. Luego, el agrupamiento de estas especies metálicas se ha controlado mediante tratamientos de activación en diferentes atmósferas (inerte, oxidativa y reductiva) y seguido por XAS de manera detallada. El objetivo principal del trabajo actual es demostrar que tanto XANES como EXAFS pueden proporcionar información valiosa y, en cierto punto, innovadora durante el control de especies metálicas (en términos de tipo y tamaño de las especies). Aprovechando los procedimientos de análisis inusuales, como el análisis de los cumulantes, el ajuste de la parte imaginaria de la transformada de Fourier y otros, es posible obtener información refinada sobre los sistemas investigados. En la sección de introducción, se proporciona una compilación de estudios en los que se ha utilizado XAS como técnica importante para caracterizar especies metálicas en materiales porosos. Conscientes de que las personas pueden usar dicha introducción como base para estudios más complejos en el futuro, la discusión se ha dirigido tentativamente hacia este objetivo. El capítulo 4 se centra en el estudio de la influencia de los precursores de paladio y la naturaleza del soporte en las nanopartículas resultantes. El proceso de activación completo, es decir, la transformación precursor --> nanopartícula, ha sido seguido por XAS in situ. El análisis estuvo compuesto por el punto de partida (material impregnado), calcinación en flujo de O2 y reducción posterior con H2. La consecuencia del uso de diferentes precursores metálicos y soportes se ha discutido en términos del número de coordinación promedio obtenido a partir del análisis de datos de EXAFS, que fue respaldado por técnicas de caracterización de laboratorio. El capítulo 5 está dedicado al estudio de la agrupación de plata durante y después de los tratamientos de activación utilizando zeolitas de poro pequeño intercambiadas con plata como precursores y nanocontenedores. Se ha estudiado la influencia de la estructura y la composición química de los materiales basados en plata sobre las especies metálicas formadas en diferentes condiciones de agrupamiento y redispersión del metal (calcinación usando atmósferas distintas, reducción en H2, redispersión en O2) utilizando métodos de caracterización in situ o ex situ. Después, se discuten las consecuencias catalíticas de las zeolitas que contienen Ag en la reacción de SCO-NH3. En esta sección, la combinación de XAS in situ con varias técnicas de laboratorio ha demostrado ser fundamental para un completo entendimiento del trabajo. Finalmente, una lista de proyectos desarrollados en paralelo a esta tesis se proporciona al final de este documento.
The aim of this thesis is to study the clustering and growth of metallic species either confined or supported in porous materials by in situ X-ray absorption spectroscopy. To accomplish this task, palladium and silver species were introduced into porous materials (¿-alumina, activated carbon and zeolites) by wetness impregnation and ion-exchange methods, respectively. Then, the clustering of these metallic species was controlled by activation treatments in different atmospheres (inert, oxidative and reductive) and followed by XAS in a comprehensive way. The principal goal of current work is to demonstrate that both XANES and EXAFS can provide valuable and, at certain point, innovative information during tuning of metallic species (in terms of type and size). Taking advantage of unusual analysis procedures, such as cumulant approach, fitting of imaginary part of Fourier transform and others, it is possible to obtain refined information about the investigated systems. In the introduction section, a compilation of studies in which XAS was used as important technique to characterize metallic species in porous materials is provided. Conscious that people can use such introduction as a basis for more complex studies in the future, the discussion has been tentatively directed toward this goal. The chapter 4 is focused on the study of the influence of palladium precursors and the nature of support on the resultant nanoparticles. The whole activation process, i.e. the transformation precursor --> nanoparticle, was followed in situ by XAS. The analysis pathway was composed by the starting point (as-impregnated), calcination in O2 flow and posterior reduction with H2. The consequence of using distinct metal precursors and supports were discussed in terms of average coordination number obtained from EXAFS data analysis, which was co-supported by laboratory characterization techniques. The chapter 5 is dedicated to the study of silver clustering during and after activation treatments using Ag-containing small-pore zeolites as precursors and nanocontainers. The influence of framework structure and chemical composition of Ag-based materials on formed Ag species at different clustering and metal redispersion conditions (calcination using distinct atmospheres, reduction in H2, redispersion in O2) were studied using either in situ or ex situ characterization methods. After, the catalytic consequences of tuned Ag-containing zeolites in SCO-NH3 are discussed. In this section, the combination of in situ XAS with several laboratory techniques proved to be pivotal to have a full picture of the investigated system. Finally, a list of projects developed in parallel to this thesis is provided at the end of this document.
L'objectiu d'aquesta tesi és estudiar l'agrupació i el creixement d'espècies metàl·liques confinades o suportades en materials porosos mitjançant espectroscòpia d'absorció de raigs X in situ. Per a això, les espècies de pal·ladi i plata s'han introduït en materials porosos (¿-alúmina, carbó activat i zeolites) per mitjà de la impregnació via humida i mètodes d'intercanvi iònic, respectivament. Una vegada preparats els materials, l'agrupament de les espècies metàl·liques s'ha controlat fent ús de tractaments d'activació en diferents atmosferes (inert, oxidant i reductora) s'ha estudiat exhaustivament per XAS. L'objectiu principal del treball és demostrar que tant el XANES com l'EXAFS proporcionen informació rellevant i, en certa manera, innovadora per al control d'espècies metàl·liques (en termes de tipus i grandària d'aquestes espècies). Fent ús de procediments de tractament de dades no molt habituals com l'anàlisi de cumulants, l'ajust de la part imaginària de la transformada de Fourier i altres, és possible obtenir informació detallada sobre els sistemes estudiats. En l'apartat de la introducció, es proporciona una recopilació d'estudis en els quals s'ha utilitzat XAS com a tècnica principal per a caracteritzar les anomenades espècies metàl·liques en materials porosos. Aquesta introducció ha estat redactada per a que puga servir com a punt de partida per a futurs estudis que requereixen la utilització de XAS per a la caracterització de les espècies metàl·liques presents en els catalitzadors. El capítol 4 es centra en l'estudi de la influència dels precursors de pal·ladi i la naturalesa del suport front a les nanopartícules resultants. El procés d'activació, és a dir, la transformació precursor --> nanopartícula, ha sigut estudiat per XAS in situ. L'anàlisi per XAS va comprendre els següents passos: punt de partida (material impregnat), calcinació en flux d'O2 i reducció posterior amb H2. La utilització de diferents precursors i suports metàl·lics ha permès dur a terme una discussió, referent al nombre de coordinació mitjà obtingut a partir de l'anàlisi de dades de la zona EXAFS, que ha estat recolzat per altres tècniques de caracterització. El capítol 5 s'ha dedicat a l'estudi de l'agrupació de plata intercanviada en els catalitzadors durant i després dels tractaments d'activació. S'han utilitzat zeolites de porus xicotet, com la CHA i RHO, intercanviades amb plata. L'estudi de la influència de l'estructura zeolítica i la composició química dels materials enfront dels diferents tractaments d'activació (calcinació utilitzant diferents atmosferes, reducció en presència d'H2, re-dispersió en atmosfera d'O2) es va realitzar fent ús de mètodes de caracterització in situ o ex situ. A continuació, es discuteix la influència d'aquestes espècies metàl·liques formades, utilitzant els diferents mètodes d'activació, per a la reacció d'SCO-NH3. En aquest sentit, s'ha demostrat que la combinació de XAS in situ amb diverses tècniques habituals de laboratori és fonamental per al desenvolupament d'aquest treball. Finalment, es presenta una llista de projectes, en els quals també s'ha treballat paral·lelament, on s'ha utilitzat XAS com a tècnica de caracterització.
Wittee Lopes, C. (2018). Characterization of metallic species on porous materials by in situ XAS [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/107953
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Vegelius, Johan. "X-ray Spectroscopic Studies of Materials for Nuclear Technology." Doctoral thesis, Uppsala universitet, Mjukröntgenfysik, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-160362.

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X-ray spectroscopic experiments, including X-ray absorption spectroscopy (XAS), X-ray emission spectroscopy (XES) and resonant inelastic X-ray scattering (RIXS), were performed in a large energy range (60-9000 eV) on a variety of systems, probing different elements and orbitals. The systems can preferably be divided into three groups: Actinides, copper systems and amorphous materials. We studied oxidation states of Pu in PuO2 using a closed-source experimental setup, developed by us, to lower the safety restrictions associated with such experiments. The presence of Pu with higher oxidation state than Pu(IV) was found in polycrystalline PuO2. This is an important finding since Pu with higher oxidation states has higher solubility affecting the safety of a proposed undeground repository of spent nuclear fuel which can eventually be infiltrated by groundwater. In the proposed underground repository the molecular oxygen will vanish at some point due to microbial activity and mineral oxidation. At this stage sulfur is the most important candidate for causing copper corrosion. We studied Cu films and foils exposed to sulfide solutions at both Cu L2,3, Cu K and S L2,3 edges and found for example that S L2,3 XES is useful for distinguishing between different copper sulfides and Cu Kβ XES can be used to identify monovalent Cu compounds. Amorphous, zirconium containing alloys are potentially useful materials for future nuclear reactors. The electronic structure of such materials was also investigated.
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Jahel, Ali. "Étude de l'ajout d'un promoteur au système Pt-Sn supporté sur alumine chlorée utilisé en reformage catalytique." Thesis, Montpellier 2, 2010. http://www.theses.fr/2010MON20233.

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L'objectif de ce travail était d'étudier de manière approfondie l'effet de l'indium dans des catalyseurs trimétalliques de reformage catalytique à base de platine, étain et indium. Des catalyseurs ont ainsi été synthétisés selon différents protocoles de préparation et de multiples caractérisations (spectroscopies Mössbauer d'étain, XANES, EXAFS, IR-CO, MEBT, chimisportion du CO, TPR et TPD) ont été mises en oeuvre afin d'élucider l'impact de l'indium sur la nature des phases métalliques présentes au sein du catalyseur. Il a ainsi été montré que la nature des sites métalliques dépend de la méthode d'introduction de l'indium. Quand l'indium est précipité avec la source d'alumine des alliages de type PtxSn sont obtenus alors que lorsque les métaux sont imprégnés sur la surface de l'alumine des espèces subsitutionnelles Pt-Sn sont formées. Il a aussi été montré que l'augmentation de la teneur en indium entraine une augmentation de la concentration atomique d'étain dans les alliage PtxSn et un remplacement de l'étain par l'indium dans les espèces substitutionnelles. Nous avons également réussi à préparer des catalyseurs avec des quantités élevées d'alliage Pt3Sn sur la base des connaissances acquises sur l'impact de l'indium et en déposant l'étain par une réaction organométallique contrôlée de surface. D'un point de vue catalytique, les tests de reformage du n-heptane mettent en évidence l'impact positif de l'indium puisque les catalyseurs à base de Pt-Sn-In sont moins sélectifs pour les réactions parasites d'hydrogénolyse et d'hydrocraquage et plus sélectifs pour l'isomérisation que les catalyseurs à base de Pt-Sn
This work consists of a detailed study on the effect of indium in alumina supported trimetallic PtSnIn-based naphtha reforming catalysts. These catalysts were reproduced using different preparation protocols and the indium effect was investigated using 119Sn Mössbauer spectroscopy, XANES, EXAFS spectroscopies, IR-CO, STEM, CO chemisorption, TPR and TPD. It appears that the nature of the metallic active centres depends on the method with which indium was introduced. When co-precipitating the indium precursor with the Al source, PtxSn alloys were formed, whereas when metals were impregnated on the surface, substitutional Pt-Sn alloys were observed. Increasing the In content in the frst type of catalysts leads to an increase in the Sn concentration in PtxSn alloys, whereas a gradual replacement of Sn by indium in susbstitutinal alloys is observed in the second type of catalysts. These results allowed preparing catalysts with high Pt3Sn alloy contents using the effect of indium in catalysts prepared by Sn organometallic controlled surface reactions (CSR). From a catalytic point of view, n-heptane reforming tests show that trimetallic PtSnIn-based catalysts are less selective to hydrogenolysis and hydrocracking reactions, and highly selective to isomerisation, compared to the bimetallic PtSn-based catalyst
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Dehlinger, Mael. "XAS-XEOL and XRF spectroscopies using near field microscope probes for high-resolution photon collection." Thesis, Aix-Marseille, 2013. http://www.theses.fr/2013AIXM4048/document.

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Les microscopes en champ proche permettent d'obtenir la topographie d'un échantillon avec une résolution pouvant atteindre la résolution atomique. Les spectroscopies de rayons-X sont des méthodes de caractérisation qui permettent de déterminer la composition et la structure élémentaire de l'échantillon avec une précision inférieure à l'Ångström. Nous avons choisi de coupler ces deux techniques en collectant localement la luminescence visible issue de l'échantillon par la pointe-sonde d'un microscope à force de cisaillement, constituée d'une fibre optique effilée de faible ouverture. Cette technique a été utilisée pour caractériser des échantillons semiconducteurs micro- et nano-structurés afin d'en obtenir simultanément la topographie et la cartographie de luminescence locale. Afin de pouvoir étendre ce concept à d'autres types de matériaux, la faisabilité de la collecte de la fluorescence X locale a été évaluée avec la microsource. Pour cela la fluorescence X émise par un échantillon a été collectée par un capillaire cylindrique équipant un détecteur EDX. L'influence du diamètre du capillaire sur le niveau de signal a été mesurée. Une simulation numérique a été développée afin d'estimer le niveau de signal obtenu en utilisant un capillaire de 1 µm de diamètre et d'optimiser la géométrie du système. En couplant la microscopie en champ proche et l'analyse XRF, à la lumière de ces résultats, il sera possible d'atteindre 100 nm de résolution latérale en environnement synchrotron et moins de 1 µm à l'aide d'une source de laboratoire. Il serait alors possible de sélectionner un objet particulier sur une surface et d'en faire l'analyse élémentaire
Scanning Probe Microscopes allow to obtain sample topography up to atomic resolution. X-ray spectroscopies allow elemental and structural analysis of a sample with accuracy better than 1 Å. The lateral resolution is limited by the primary beam diameter, currently a few µm². We have chosen to couple this two technics. Local sample visible luminescence is collected through a low aperture sharp optical fibre, probe of a shear force microscope. This technique was used to characterize microstructured semiconducting samples to achieve simultaneously the surface topography and luminescence mapping. The results were obtained using either synchrotron radiation or a laboratory microsource equipped with a polycapillary lens. To extend this concept to a wider variety of materials, local XRF collection by an EDX detector equipped with a cylindrical X-ray capillary was tested. A cobalt sample irradiated with the microsource was used for technique evaluation. The signal magnitude dependence with the capillary diameter was measured. Modelling and numerical calculations were developed to estimate the signal magnitude that could be detected using a 1 µm diameter capillary. The optimal system geometry was determined. Scanning Probe Microscopy combined to XRF analysis could thereby lead to simultaneous acquisition of sample topography and chemical mapping. The expected lateral resolution using synchrotron radiation is 100 nm while sub 1 µm resolution is realistic with a laboratory source. This technique would allow to point a peculiar micro- or nano-object on the surface and to perform its chemical analysis
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Kristiansen, Paw. "In situ X-Ray Spectroscopy of Ethylene Epoxidation over Ag and studies of Li-ion batteries and Cu sulfidation." Doctoral thesis, Uppsala universitet, Molekyl- och kondenserade materiens fysik, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-209204.

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This thesis is based on experiments applying synchrotron based X-ray Absorption Spectroscopy(XAS) and Resonant Inelastic X-ray Scattering (RIXS) in the soft X-ray region to energy related systems. The main work of this thesis has been to develop a reaction cell that allowed for in situ XAS and RIXS investigations of the partial epoxidation of ethylene over a Ag catalyst at 1 atm and up to 250C. The developed in situ cell can be used in two sample modes: 1) the Ag catalyst is deposited directly onto the vacuum separating membrane with the reaction gases flowing beneath it or 2) a slightly compressed Ag powder sample is at a distance to the vacuum membrane with the reaction gases flowing between the Ag powder sample and the membrane.Both sample modes offers the total florescence yield, TFY, and the total electron yield, TEY, to be recorded simultaneously. By means of the developed in situ cell a number of oxygen species, residing in/on the Ag surface or in the Ag bulk, have been detected. We claim to detect adsorbed O2 under epoxidation conditions, as well as Ag–O–H groups. We are also able to monitor changes of the absorbed oxygen as we change the composition of the reaction gas feed. The first charging cycle of Li-ion batteries have been investigate by ex situ measurements on the cathode Li2-xMnSiO4 and the anode composite LixNi0:5TiOPO4/C . The initial crystalline material becomes amorphous due to lithiation during the first first charging. We find that the redox behaviors of these two states are significantly different. Sulfidation of natural copper oxides are is found to be strongly promoted when it is grown on the host metal by a disproportionation.
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Davies, Graeme John. "Optically detected X-ray absorption spectroscopy (OD-XAS) study of InGaN/GaN quantum well and quantum dot nanostructures." Thesis, University of Manchester, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.516410.

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InGaN/GaN single quantum well (SQW) and quantum dot (QD) samples were studied using optically detected X-ray absorption spectroscopy (OD-XAS). This is a powerful technique, capable of linking local structural environment information with the luminescence emission processes present. Ga K-edge OD-EXAFS analysis shows this technique to be site-selective for these samples and, from the emission related to the QW or QD structure, a percentage indium value was determined for each sample. Possible reasons why this siteselectivity is observed are considered, along with the implication of the results with respect to the nature of the mechanism responsible for exciton localisation within these structures. Further investigations were performed on the QD sample, including a depth profiling study based on spectra obtained at several different excitation energies and an analysis of the OD-XANES at the N K-edge. The application of pumpprobe micro-imaging OD-XAS to these types of samples is also examined.
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Poirier, Mathilde. "Fonctionnalisation et cristallochimie de talcs synthétiques submicroniques." Thesis, Toulouse 3, 2019. http://www.theses.fr/2019TOU30237.

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Le talc synthétique est un matériau à fort intérêt industriel du fait de sa taille submicronique, de sa large surface spécifique (> 300 m²/g), et de ses propriétés hydrophiles, qui lui offrent un large éventail d'applications dans des secteurs industriels variés (polymères, cosmétiques, papiers, peintures, médecine, ...). Dans cette thèse, les potentialités d'adsorption du matériau ont été testées vis-à-vis de différents composés organiques et/ou inorganiques à propriétés physico-chimiques souhaitées (composés colorés et/ou fluorescents, nanoparticules métalliques), afin d'élaborer de nouvelles charges minérales fonctionnelles et innovantes (e.g. talcs synthétiques fluorescents). Les résultats montrent que le matériau présente une forte capacité à adsorber les composés testés, qui est bien supérieure à celle de son homologue naturel de taille pluri-micronique. La recherche des mécanismes d'adsorption se produisant à l'interface "minéral - adsorbat" a par la suite conduit à étudier de plus près la cristallochimie du talc synthétique non fonctionnalisé, en utilisant plusieurs méthodes de caractérisation comme la Diffraction des Rayons (DRX), la spectroscopie de Résonance Magnétique Nucléaire (RMN), ou bien encore la spectroscopie d'Absorption des Rayons X (XAS). Outre le fait que de grandes avancées ont été faites sur la caractérisation cristallochimique des particules, les résultats majeurs montrent que les minéraux synthétiques ne doivent pas être regardés de la même manière que les minéraux naturels, du fait de leur taille nanométrique qui engendre obligatoirement une perturbation des signaux observés. Les résultats montrent notamment que les méthodes de caractérisation qui sont classiquement utilisées en DRX pour calculer les distances inter-réticulaires ne doivent pas être appliquées sur les nanomatériaux du fait du faible empilement des particules suivant l'axe cristallographique c*. Il faut pour cela faire appel à des méthodes de simulation numériques pour déterminer les valeurs des distances inter-réticulaires réelles. De la même manière, les résultats montrent que les signaux RMN sont également impactés par la taille nanométrique des particules du fait d'une différenciation des signaux provenant du cœur des particules, de ceux provenant des surfaces externes des particules. Ces résultats ont été mis en évidence en combinant une approche expérimentale par RMN à une approche théorique par DFT (Density Functional Theory).[;;;]
Synthetic talc is a material of great industrial interest because of its submicronic size, its large specific surface area (> 300 m²/g), and its hydrophilic properties, offering a wide range of applications in the fields of polymers, cosmetics, papers, paints, or medecine. In this thesis, the adsorption capacity of the material was tested towards different organic and/or inorganic compounds of desired physicochemical properties (coloured and/or fluorescent compounds, metallic nanoparticles), to elaborate new mineral fillers with functional and innovative characteristics (e.g. fluorescent synthetic talc particles). The results show that synthetic talc particles possess a much higher adsorption capacity towards organic and inorganic compounds, compared to natural plurimicron-sized talc particles. Research on the adsorption mechanisms occuring at the " mineral - adsorbate " interface was followed by the study of the crystal-chemistry of the material, using a combination of several characterization techniques such as X-Ray Diffraction (XRD), Nuclear Magnetic Resonance spectroscopy (NMR), or X-Ray Absorption spectroscopy (XAS). Beyond the fact that a great progress was made on the overall crystal-chemistry of the particles, the main results show that " synthetic minerals " should not be considered in the same way as " natural minerals " due to their nanometric size which necessarily disturbed the observed signals. As an example, the methods conventionally used in XRD to determine the interplanar spacings should not be applied on nanomaterials because of their very low particle stacking and numerical simulations shall be used instead. Similarly, our study shows that NMR signals are also impacted by the nanometric size of the particles because of a spectral differentiation of the signals coming from the bulk of the particles versus the ones coming from the external surfaces of the particles. These results were highlighted by combining an experimental NMR approach and a theoretical DFT (Density Functional Theory). Those external surfaces, which contain crystalline defects, are probably responsible for the high adsorption capacity of the material, and may explain some of the crystallogenesis processes that have been observed by XAS spectroscopy. To conclude, nano-sized lamellar synthetic materials represent a great tool to investigate the surface crystal-chemistry of natural minerals, as they revealed new contributions which were previously undetectable in larger-sized minerals
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Helmstedt, Andreas [Verfasser]. "Probing the magnetic properties of [MnIII6CrIII]3+ single-molecule magnets by XAS, XMCD and spin-resolved electron spectroscopy / Andreas Helmstedt." Bielefeld : Universitätsbibliothek Bielefeld, 2014. http://d-nb.info/1068621702/34.

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Zamora, Torres David, and Felix Abeln. "Design of an In-situ cell, for hard X-ray spectroscopy of surfaces used in high-pressure and high-temperature experiments : Design av en In-situ cell för intensiv röntgenspektroskopi i högtryck- högtemperaturexperiment." Thesis, Malmö universitet, Institutionen för materialvetenskap och tillämpad matematik (MTM), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-45607.

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This project analyzes how an in-situ cell can be developed to withstand high amounts of pressure and temperature of at least 100 bar and 500 °C. A theoretical prototype will be created as a product for Malmö University and other researchers to use or improve. To make this possible, the five step method was used to present a symmetric geometrical concept for the cell. That geometric concept was designed in PTC Creo (Version 6.0.2.0 & 7.0) in 3D and drawings in 2D. The programs GRANTA EduPack (Version 2020 \& Version 2019) along with Hephaestus was used to determine a material selection that will be able to tolerate temperature, pressure and be at least ten percent transparent, to be able for the X-ray to pass through the material and into the sample. The Finite Element Method (FEM) was used to ensure that the cell adheres to the set values of pressure and not cause a catastrophic failure. The result turn out to be a elliptical three part in-situ cell of boron carbide outer shell, a beryllium main dome and a stainless steel plate for the material sample to be on top. The Finite Element Method also showed that the designed in-situ cells meet the requirements and fulfills the goal and purpose. Further development of safety features and the equipment will be needed to minimise the risk of and dangers of beryllium dust.
Detta projekt analyserar hur en in-situ cell kan utvecklas för att motstå höga mängder tryck och temperatur på minst 100 bar och 500 °C . En teoretisk prototyp kommer att skapas som en produkt för Malmö universitet och andra forskare att använda eller förbättra. För att göra detta möjligt användes femstegsmetoden för att presentera ett symmetriskt och geometriskt koncept för cellen. Det geometriska konceptet kommer att utformas 3-dimensionellt i PTC Creo (Version 6.0.2.0  7.0) och 2-dimensionella ritningar . GRANTA EduPack-programmen (Version 2020 \& Version 2019) tillsammans med Hephaestus användes för att bestämma ett materialval som kommer att kunna tolerera temperatur, tryck och vara minst tio procent transparent för att röntgenstrålningen ska kunna passera genom materialet och in i provet. Finite Element Method (FEM) kommer att användas för att säkerställa att cellen följer de inställda tryckvärdena och inte orsakar katastrofala fel. Resultatet visar sig vara en elliptisk tredelad in-situ cell av borkarbid som ett yttre skal, beryllium som huvudkupol och en rostfri stålplatta som underlag för materialprovet. Finite Element Method visade också att den designade in-situ-cellen uppfyller kraven och därför uppfyller målet och syftet. Detta innebär att vidareutveckling av säkerhetsfunktioner och utrustning kommer att behövas för att minimera risken för berusning från berylliumdammet.
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Books on the topic "XAS spectroscopy"

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Crist, B. Vincent. Handbook of monochromatic XPS spectra. Chichester: John Wiley, 2000.

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Cultural heritage materials: An XPS approach. New York: Nova Science Publishers, 2012.

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1948-, Briggs D., ed. High resolution XPS of organic polymers: The Scienta ESCA300 database. Chichester [England]: Wiley, 1992.

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An introduction to surface analysis by XPS and AES. Chichester, UK: Wiley, 2004.

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Bunker, Grant. Introduction to XAFS: A practical guide to X-ray absorption fine structure spectroscopy. New York: Cambridge University Press, 2010.

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Surface analysis of polymers by XPS and static SIMS. Cambridge, U.K: Cambridge University Press, 1998.

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Grasserbauer, M. Angewandte Oberflächenanalyse: Mit SIMS Sekundär-Ionen-Massenspektrometrie, AES Auger-Elektronen-Spektrometrie, XPS Röntgen-Photoelektronen-Spektrometrie. Berlin: Springer-Verlag, 1986.

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Moulder, John F. Handbook of x-ray photoelectron spectroscopy: A reference book of standard spectra for identification and interpretation of XPS data. Eden Prairie, Minn: Perkin-Elmer Corporation, Physical Electronics Division, 1992.

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Saffarini, Ghassan. X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), differential scanning calorimetry (DSC) and density study of ternary chalcogenide glasses based on Ge-Se and Ge-S. Uxbridge: Brunel University, 1991.

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High-Resolution XAS/XES: Analyzing Electronic Structures of Catalysts. Taylor & Francis Group, 2014.

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Book chapters on the topic "XAS spectroscopy"

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Filipponi, Adriano, and Paola D’Angelo. "XAS in Liquid Systems." In X-Ray Absorption and X-Ray Emission Spectroscopy, 745–71. Chichester, UK: John Wiley & Sons, Ltd, 2016. http://dx.doi.org/10.1002/9781118844243.ch25.

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Lamberti, Carlo, and Jeroen A. van Bokhoven. "Introduction: Historical Perspective on XAS." In X-Ray Absorption and X-Ray Emission Spectroscopy, 1–21. Chichester, UK: John Wiley & Sons, Ltd, 2016. http://dx.doi.org/10.1002/9781118844243.ch1.

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Elnaggar, Hebatalla, Pieter Glatzel, Marius Retegan, Christian Brouder, and Amélie Juhin. "X-ray Dichroisms in Spherical Tensor and Green’s Function Formalism." In Springer Proceedings in Physics, 83–130. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-64623-3_4.

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AbstractIn this book chapter, our goal is to provide experimentalists and theoreticians with an accessible approach to the measurement or calculation of X-ray dichroisms in X-ray absorption spectroscopy (XAS). We start by presenting the key ideas of different calculation methods such as density functional theory (DFT) and ligand-field multiplet (LFM) theory and discuss the pros and cons for each approach. The second part of the chapter is dedicated to the expansion of the XAS cross section using spherical tensors for electric dipole and quadrupole transitions. This expansion enables to identify a set of linearly independent spectra that represent the smallest number of measurements (or calculations) to be performed on a sample, in order to extract all spectroscopic information. Examples of the different dichroic effects which can be expected depending on the type of transitions and on the symmetry of the system are then given.
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Itié, Jean-Paul, François Baudelet, and Jean-Pascal Rueff. "High Pressure XAS, XMCD and IXS." In X-Ray Absorption and X-Ray Emission Spectroscopy, 385–405. Chichester, UK: John Wiley & Sons, Ltd, 2016. http://dx.doi.org/10.1002/9781118844243.ch14.

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García, Joaquín, Gloria Subías, and Javier Blasco. "XAS Studies on Mixed Valence Oxides." In X-Ray Absorption and X-Ray Emission Spectroscopy, 459–84. Chichester, UK: John Wiley & Sons, Ltd, 2016. http://dx.doi.org/10.1002/9781118844243.ch17.

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Gianolio, Diego. "How to Start an XAS Experiment." In X-Ray Absorption and X-Ray Emission Spectroscopy, 99–124. Chichester, UK: John Wiley & Sons, Ltd, 2016. http://dx.doi.org/10.1002/9781118844243.ch5.

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Troć, R. "UTe: X-ray Absorption Spectroscopy (XAS) and Photoelectron Spectroscopy (PES)." In Actinide Monochalcogenides, 891–96. Berlin, Heidelberg: Springer Berlin Heidelberg, 2009. http://dx.doi.org/10.1007/978-3-540-47043-4_191.

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Troć, R. "Actinide Monotellurides: X-ray Absorption Spectroscopy (XAS) and Photoelectron Spectroscopy (PES)." In Actinide Monochalcogenides, 866–68. Berlin, Heidelberg: Springer Berlin Heidelberg, 2009. http://dx.doi.org/10.1007/978-3-540-47043-4_186.

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Smith, Joseph V., and William L. Brown. "Spectroscopy — IR, Raman, NMR, NQR, EPR, NGR (Mössbauer), XAS, EXAFS, ESCA, XPS." In Feldspar Minerals, 244–67. Berlin, Heidelberg: Springer Berlin Heidelberg, 1988. http://dx.doi.org/10.1007/978-3-642-72594-4_11.

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Lamberti, Carlo, Elisa Borfecchia, Jeroen A. van Bokhoven, and Marcos Fernández-García. "XAS Spectroscopy: Related Techniques and Combination with Other Spectroscopic and Scattering Methods." In X-Ray Absorption and X-Ray Emission Spectroscopy, 303–50. Chichester, UK: John Wiley & Sons, Ltd, 2016. http://dx.doi.org/10.1002/9781118844243.ch12.

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Conference papers on the topic "XAS spectroscopy"

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Glatzel, P., M. Sikora, S. G. Eeckhout, O. V. Safonova, G. Smolentsev, G. Pirngruber, J. A. van Bokhoven, J. D. Grunewaldt, and M. Tromp. "Hard X-Ray Photon-In-Photon-Out Spectroscopy with Lifetime Resolution — of XAS, XES, RIXSS and HERFD." In SYNCHROTRON RADIATION INSTRUMENTATION: Ninth International Conference on Synchrotron Radiation Instrumentation. AIP, 2007. http://dx.doi.org/10.1063/1.2436402.

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Glover, C., J. McKinlay, M. Clift, B. Barg, J. Boldeman, M. Ridgway, G. Foran, R. Garret, P. Lay, and A. Broadbent. "Status of the X-Ray Absorption Spectroscopy (XAS) Beamline at the Australian Synchrotron." In X-RAY ABSORPTION FINE STRUCTURE - XAFS13: 13th International Conference. AIP, 2007. http://dx.doi.org/10.1063/1.2644692.

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Geurts, Jean, Jo Finders, O. Kayser, Berhard Opitz, M. Maassen, R. Westphalen, and P. Balk. "Selectively grown InxGa1-xAs and InxGa1-xP structures: locally resolved stoichiometry determination by Raman spectroscopy." In Physical Concepts of Materials for Novel Optoelectronic Device Applications, edited by Manijeh Razeghi. SPIE, 1991. http://dx.doi.org/10.1117/12.24437.

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Song, J. J., Y. S. Yoon, P. S. Jung, A. Fedotowsky, and Y. B. Kim. "Optical Characterization Of GaAs/AlxGai-xAs Quantum Well Structures And Superlattices By Photoluminescence And Photoexcitation Spectroscopy." In Semiconductor Conferences, edited by Orest J. Glembocki, Fred H. Pollak, and Jin-Joo Song. SPIE, 1987. http://dx.doi.org/10.1117/12.940892.

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Chen, L. X., G. B. Shaw, E. C. Wasinger, X. Zhang, K. Attenkofer, and Guy Jennings. "Molecular Structural Dynamics of Photoactive Transition Metal Complexes in Solar Energy Conversion Studied by Ultrafast Optical Spectroscopy and LITR-XAS." In X-RAY ABSORPTION FINE STRUCTURE - XAFS13: 13th International Conference. AIP, 2007. http://dx.doi.org/10.1063/1.2644681.

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Pinzani, M. Caterina Camerani, Britt-Marie Steenari, and Oliver Lindqvist. "Direct Determination of Cadmium Speciation in MSW and Biomass Single Fly Ash Particles Using SR Based µ-XR Spectroscopy Techniques." In 17th International Conference on Fluidized Bed Combustion. ASMEDC, 2003. http://dx.doi.org/10.1115/fbc2003-021.

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Cadmium is a toxic metal causing environmental concern in connection with utilization and land filling of ash. Knowledge about the chemical associations of Cd in ash is fundamental in the understanding of its solubility and leachability from the ash. In the work presented here, the content, distribution and chemical forms of Cd on/in individual Municipal Solid Waste (MSW) and biomass fly ash particles have been investigated in situ by Synchrotron Radiation induced μ-X-ray fluorescence, absorption spectrometry (XAS) and fluorescence tomography. These X-ray micro-beam techniques can be used to reveal spatially resolved information about structural and chemical properties of particles. The use of an excitation energy of 27 keV made it possible to detect trace metals, such as Cd at ppm levels, but also other elements, like Ca, K, Cl and Br. Absorption spectra of Cd in the energy range around the absorption edge of Cd (26.71 keV) were recorded for micron-sized spots of ash particles. Fluorescence tomography was then use to establish if Cd compounds are situated on the particle surface (i.e. most prone to leaching) or at some depth within the particle, where they might be more shielded from chemical attack by water. The measurements indicated Cd to be preferably concentrated in some small areas (“hot-spots”) with high concentration (up to 200 ppm) in MSW fly ash particles and in a homogeneous distribution over the whole particle surface in the case of biomass. Comparisons of XAS spectra of fly ashes and reference compounds showed Cd to be present in the oxidation state +2 and mainly as CdSO4, CdO and CdCl2. Although previous studies have indicated Cd to be enriched in the smaller-size ash particles, in this study Cd was found to be reasonably well distributed throughout all the particle sizes investigated. Based on the results obtained, possible reaction mechanisms involving Cd are suggested.
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Street, Kenneth W., and Marjorie F. Sovinski. "Analysis of Black Bearing Balls From a Space Shuttle Body Flap Actuator." In World Tribology Congress III. ASMEDC, 2005. http://dx.doi.org/10.1115/wtc2005-63539.

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A significantly deteriorated ball bearing mechanism from a body flap actuator on Space Shuttle OV-103 was disassembled and the balls submitted for analysis in conjunction with Return to Flight activities. The OV-103 balls, referred to as the “black balls”, were subjected to X-ray photoelectron spectroscopy (XPS), Fourier Transform Infrared (FT-IR) and Raman micro spectroscopy, surface profilometry, and optical and electron microscopy. The spectroscopic results in combination with microscopy analysis allowed a determination of the lubricant degradation pathway. The chemical attack mechanism does not adequately explain the unique visual appearance of the black balls. Numerous efforts have unsuccessfully focused on duplication of the phenomena causing this unique surface structure and appearance of the black balls. Further detail will be presented supporting these conclusions along with plausible explanations of the unique black appearance to the balls.
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Reich, Tobias, Tatiana Ye Reich, Samer Amayri, Jakob Drebert, Nidhu L. Banik, Razvan A. Buda, Jens Volker Kratz, and Norbert Trautmann. "Application of XAFS Spectroscopy to Actinide Environmental Science." In X-RAY ABSORPTION FINE STRUCTURE - XAFS13: 13th International Conference. AIP, 2007. http://dx.doi.org/10.1063/1.2644467.

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Younan, Hua, Shen Yue, Chen Yixin, Fu Chao, and Li Xiaomin. "Studies on a Qualification Method (OSSD) for Microchip Al Bondpads." In ISTFA 2015. ASM International, 2015. http://dx.doi.org/10.31399/asm.cp.istfa2015p0295.

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Abstract In authors’ previous paper, an OSAT [Optical, SEM (Scanning Electron Microscopy), Auger (Auger Electron Spectroscopy) and TEM (Transmission Electron Microscopy)] methodology was developed for qualification of microchip aluminum (Al) bondpads. Using the OSAT methodology, one can qualify microchip Al bondpads. In this paper, we will further study the NSOP (Non-Stick On Pad) problem on microchip Al bondpads. A new qualification methodology, OSSD [(Optical, SEM, and Surface and Depth profiling X-ray Photoelectron Spectroscopy (XPS)] will be proposed, in which XPS surface analysis is used to check the contamination level of fluorine and carbon on bondpad surfaces instead of Auger analysis. XPS depth profiling analysis will also be used to measure Al oxide thickness instead of TEM analysis. By using OSSD, Al bondpads can be qualified with both reduced costs and shortened turnaround times versus OSAT.
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Wu, LinFeng, Ming Li, J. H. Lee, Jecy Zhou, Chorng Niou, and W. T. Kary Chien. "A Correlation Study between XPS and AES Quantitative Analysis of Nitrogen Concentration in Gate Oxide." In ISTFA 2004. ASM International, 2004. http://dx.doi.org/10.31399/asm.cp.istfa2004p0471.

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Abstract Accurate characterization of the nitrogen concentration and distribution in ultra thin nitrided silicon gate oxide plays the same important role as the fabrication technology itself during the development of 90nm and beyond gate oxide manufacturing process. Based on the measurement results of XPS (X-ray photoelectron spectroscopy) as reference, a correlation study was taken between XPS and AES (Auger electron spectroscopy) data in this paper. The study shows that, by optimizing the experiment conditions of AES such as beam energy, beam current and take off angle, and introducing proper corrective factor, AES can be used as a useful and reliable characterization tool during the monitoring measurement of Nitrogen concentration in ultra thin (<2nm) nitrided silicon gate oxide.
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Reports on the topic "XAS spectroscopy"

1

Brown, J. R., M. Kasrai, and G. M. Bancroft. Application of direct surface sensitive x-ray (XPS/XAS) and electron (AES/SAM) spectroscopic techniques to coal and the fossil fuel cycle. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 1991. http://dx.doi.org/10.4095/304492.

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2

Wagner, C. D. NIST x-ray photoelectron spectroscopy (XPS) database. Gaithersburg, MD: National Bureau of Standards, 1990. http://dx.doi.org/10.6028/nist.tn.1289.

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3

Wong, J., M. Froba, and E. Tamura. New XAFS spectroscopic investigations in the 1-2 keV region. Final report on LDRD program. Office of Scientific and Technical Information (OSTI), March 1996. http://dx.doi.org/10.2172/264593.

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4

Huffman, G. P., F. E. Huggins, and N. Shah. Coal liquefaction process streams characterization and evaluation: Investigation of the forms of sulfur in five Wilsonville resid samples by XAFS and moessbauer spectroscopy. Office of Scientific and Technical Information (OSTI), November 1992. http://dx.doi.org/10.2172/6878966.

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Huffman, G. P., F. E. Huggins, and N. Shah. Coal liquefaction process streams characterization and evaluation: Investigation of the forms of sulfur in five Wilsonville resid samples by XAFS and moessbauer spectroscopy. Office of Scientific and Technical Information (OSTI), November 1992. http://dx.doi.org/10.2172/10123839.

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6

Bitterwolf, Thomas E. Time-resolved XAFS spectroscopic studies of B-H and N-H oxidative addition to transition metal catalysts relevant to hydrogen storage. Office of Scientific and Technical Information (OSTI), December 2014. http://dx.doi.org/10.2172/1165128.

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