Bibliografías temáticas / Grazing incidence X-ray diffraction (GIXD)

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Literatura académica sobre el tema "Grazing incidence X-ray diffraction (GIXD)"

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Publicado: 25 de mayo de 2024

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Artículos de revistas sobre el tema "Grazing incidence X-ray diffraction (GIXD)"

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Takagi, Yasuo y Masao Kimura. "Generalized grazing-incidence-angle X-ray diffraction (G-GIXD) using image plates". Journal of Synchrotron Radiation 5, n.º 3 (1 de mayo de 1998): 488–90. http://dx.doi.org/10.1107/s090904959800123x.

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A new and more `generalized' grazing-incidence-angle X-ray diffraction (G-GIXD) method which enables simultaneous measurements both of in- and out-of-plane diffraction images from surface and interface structures has been developed. While the method uses grazing-incidence-angle X-rays like synchrotron radiation as an incident beam in the same manner as in `traditional' GIXD, two-dimensional (area) detectors like image plates and a spherical-type goniometer are used as the data-collection system. In this way, diffraction images both in the Seemann–Bohlin (out-of-plane) and GIXD geometry (in-plane) can be measured simultaneously without scanning the detectors. The method can be applied not only to the analysis of the in-plane crystal structure of epitaxically grown thin films, but also to more general research topics like the structural analysis of polycrystalline mixed phases of thin surface and interface layers.
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Kainz, Manuel Peter, Lukas Legenstein, Valentin Holzer, Sebastian Hofer, Martin Kaltenegger, Roland Resel y Josef Simbrunner. "GIDInd: an automated indexing software for grazing-incidence X-ray diffraction data". Journal of Applied Crystallography 54, n.º 4 (30 de julio de 2021): 1256–67. http://dx.doi.org/10.1107/s1600576721006609.

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Grazing-incidence X-ray diffraction (GIXD) is a widely used technique for the crystallographic characterization of thin films. The identification of a specific phase or the discovery of an unknown polymorph always requires indexing of the associated diffraction pattern. However, despite the importance of this procedure, only a few approaches have been developed so far. Recently, an advanced mathematical framework for indexing of these specific diffraction patterns has been developed. Here, the successful implementation of this framework in the form of an automated indexing software, named GIDInd, is introduced. GIDInd is based on the assumption of a triclinic unit cell with six lattice constants and a distinct contact plane parallel to the substrate surface. Two approaches are chosen: (i) using only diffraction peaks of the GIXD pattern and (ii) combining the GIXD pattern with a specular diffraction peak. In the first approach the six unknown lattice parameters have to be determined by a single fitting procedure, while in the second approach two successive fitting procedures are used with three unknown parameters each. The output unit cells are reduced cells according to approved crystallographic conventions. Unit-cell solutions are additionally numerically optimized. The computational toolkit is compiled in the form of a MATLAB executable and presented within a user-friendly graphical user interface. The program is demonstrated by application on two independent examples of thin organic films.
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Breiby, Dag W., Oliver Bunk, Jens W. Andreasen, Henrik T. Lemke y Martin M. Nielsen. "Simulating X-ray diffraction of textured films". Journal of Applied Crystallography 41, n.º 2 (8 de marzo de 2008): 262–71. http://dx.doi.org/10.1107/s0021889808001064.

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Computationally efficient simulations of grazing-incidence X-ray diffraction (GIXD) are discussed, with particular attention given to textured thin polycrystalline films on supporting substrates. A computer program has been developed for simulating scattering from thin films exhibiting varying degrees of preferred orientation. One emphasized common case is that of a `fibre' symmetry axis perpendicular to the sample plane, resulting from crystallites having one well defined crystal facet towards the substrate, but no preferred in-plane orientation. Peak splitting caused by additional scattering from the totally substrate-reflected beam (two-beam approximation) and refraction effects are also included in the program, together with the geometrical intensity corrections associated with GIXD measurements. To achieve `user friendliness' for scientists less familiar with diffraction, the mathematically simplest possible descriptions are sought whenever feasible. The practical use of the program is demonstrated for a selected thin-film example, perylene, which is of relevance for organic electronics.
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Khasanah, Khasanah, Isao Takahashi, Kummetha Raghunatha Reddy y Yukihiro Ozaki. "Crystallization of ultrathin poly(3-hydroxybutyrate) films in blends with small amounts of poly(l-lactic acid): correlation between film thickness and molecular weight of poly(l-lactic acid)". RSC Advances 7, n.º 83 (2017): 52651–60. http://dx.doi.org/10.1039/c7ra10996b.

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The crystallization behavior of poly(3-hydroxybutyrate) (PHB) films in blends with small amounts of poly(l-lactic acids) (PLLAs) was investigated by grazing incidence X-ray diffraction (GIXD) and infrared-reflection absorption spectroscopy (IRRAS).
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Hafidi, K., M. Azizan, Y. Ijdiyaou y E. L. Ameziane. "Ètude des interfaces SiO2/TiO2 et TiO2/SiO2 dans la structure SiO2/TiO2/SiO2/c-Si préparée par pulvérisation cathodique radio fréquence". Canadian Journal of Physics 85, n.º 7 (1 de julio de 2007): 763–76. http://dx.doi.org/10.1139/p07-053.

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The atomic structure of the TiO2/SiO2 and SiO2/TiO2 interfaces has been investigated in SiO2/TiO2/SiO2 multilayers deposited by radio frequency reactive sputtering without breaking the vacuum on the crystalline substrate cooled by water. The characterizations of these interfaces have been performed using three complementary techniques sensitive to surface and interface state: X-ray photoelectron spectroscopy (XPS), grazing incidence X-ray diffraction (GIXD), and specular X-ray reflectometry (GIXR). The concentration profiles and Si2p and O1s core level chemical displacements show that TiO2/SiO2 and SiO2/TiO2 interfaces are very diffuse. The reflectometry measurements confirm this character and indicate that the silicon, titanium, and oxygen atomic concentrations vary gradually at the interfaces. The grazing incidence X-ray spectra indicates that the interfacial layers are not well crystallized and are formed by SiO2-TiO2, TiO, Ti2O3, Ti3O5, Ti5Si3, Ti5Si4, TiSi, and TiSi2 components.
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Ishida, Kenji, Akinori Kita, Kouichi Hayashi, Toshihisa Horiuchi, Shoichi Kal y Kazumi Matsushige. "Energy Dispersive Grazing Incidence X-ray Diffraction Study on Organic Thin Films EpitaxiaHy Grown on Crystalline Substrate". Advances in X-ray Analysis 39 (1995): 659–64. http://dx.doi.org/10.1154/s0376030800023090.

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Thin film technology is rapidly evolving today, and the characterization of the thin film and its surface have become very important issue not only from scientific but also technological viewpoints. Although x-ray diffraction measurements have been used as suitable evaluation methods in crystallography studies, its application to the structural evaluation of the thin films, especially organic one having the low electron densities, is not easy due to the small amounts of scattering volume and the high obstructive scattering noise from the substrate. However, the x-ray diffraction measurements under grazing incidence will aid not only in overcoming the such problems but also in analyzing in-plane structure of the thin films. Therefore, so-called grazing incidence x-ray diffraction (GIXD) has been recognized as one of the most powerful tools for the surface and thin film studies.
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Gobato, Ricardo, Marcia Regina Risso Gobato, Alireza Heidari y Abhijit Mitra. "Unrestricted hartree-fock computational simulation in a protonated rhodochrosite crystal". Physics & Astronomy International Journal 3, n.º 6 (6 de noviembre de 2019): 220–28. http://dx.doi.org/10.15406/paij.2019.03.00187.

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In this paper, compact effective potentials, charge distribution, Atomic Polar Tensor (APT) and Mulliken charges were studied using a unrestricted Hartree-Fock computational simulation in a protonated rhodochrosite crystal. The rhodochrosite crystal unit cell of structure CMn6O8, where the charge distribution by the molecule was verified in the UHF CEP-4G (Effective core potential (ECP) minimal basis), UHF CEP-31G (ECP split valance) and UHF CEP-121G (ECP triple-split basis). The largest load variation in the APT and Mulliken methods were obtained in the CEP-121G basis set, with δ=2.922 e δ=2.650 u.a., respectively, being δAPT> δMulliken. The maximum absorbance peaks in the CEP-4G, CEP-31G and CEP-121G basis set are present at the frequencies 2172.23 cm-1, with a normalized intensity of 0.65; 2231.4 cm-1 and 0.454; and 2177.24 cm-1 and 1.0, respectively. An in-depth study is necessary to verify the absorption by the tumoral and non-tumoral tissues of rhodochrosite, before and after irradiating of synchrotron radiation using Small–Angle X–Ray Scattering (SAXS), Ultra–Small Angle X–Ray Scattering (USAXS), Fluctuation X–Ray Scattering (FXS), Wide–Angle X–Ray Scattering (WAXS), Grazing–Incidence Small–Angle X–Ray Scattering (GISAXS), Grazing–Incidence Wide–Angle X–Ray Scattering (GIWAXS), Small–Angle Neutron Scattering (SANS), Grazing–Incidence Small–Angle Neutron Scattering (GISANS), X–Ray Diffraction (XRD), Powder X–Ray Diffraction (PXRD), Wide–Angle X–Ray Diffraction (WAXD), Grazing– Incidence X–Ray Diffraction (GIXD) and Energy–Dispersive X–Ray Diffraction (EDXRD). Later studies could check the advantages and disadvantages of rhodochrosite in the treatment of cancer through synchrotron radiation, such as one oscillator crystal.
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Holzer, Valentin, Benedikt Schrode, Josef Simbrunner, Sebastian Hofer, Luisa Barba, Roland Resel y Oliver Werzer. "Impact of sample misalignment on grazing incidence x-ray diffraction patterns and the resulting unit cell determination". Review of Scientific Instruments 93, n.º 6 (1 de junio de 2022): 063906. http://dx.doi.org/10.1063/5.0088176.

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Grazing incidence x-ray diffraction (GIXD) is a frequently used tool for the crystallographic characterization of thin films in terms of polymorph identification and determination of the crystallographic lattice parameters. Even full structure solutions are possible. To obtain highly accurate diffraction patterns, the thin film sample has to be aligned carefully with the center of the goniometer, which allows a defined incidence of the primary x-ray beam relative to the sample surface. This work studies the effect of misalignment of a thin film sample on the acquired diffraction pattern. Three potential types of misalignments are considered: the deviation of the sample surface from the center of the goniometer, an error in the incidence angle of the primary beam, and an inclination of the goniometer rotation axis from the normal of the substrate surface. The consequence of these types of sample misalignments is the shift of diffraction peaks toward specific directions in reciprocal space. Mathematical equations are given that relate the error in positions of Bragg peaks for each type of sample misalignment. Experiments with intentionally misaligned samples confirm the given formulas. In a subsequent step, the errors in the peak positions are translated to systematic errors in the estimation of the unit cell parameters. Depending on the type of misalignment, some alignment errors can be reduced or even corrected; in particular, azimuthal sample rotations prove to be advantageous in these cases. The results in this work improve the quality of GIXD measurements, in general, enabling deeper analysis like the full structure solution from the GIXD pattern on everyday basis.
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Yoshida, Masahiro, Yasunori Kutsuma, Daichi Dohjima, Kenji Ohwada, Toshiya Inami, Noboru Ohtani, Tadaaki Kaneko y Jun'ichiro Mizuki. "Development of the Compact Furnace for the In Situ Observation under Ultra-High Temperature by Synchrotron x-Ray Surface Diffraction". Materials Science Forum 858 (mayo de 2016): 505–8. http://dx.doi.org/10.4028/www.scientific.net/msf.858.505.

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We have established the grazing-incidence x-ray diffraction (GIXD) method under ultra- high temperature for in-situ crystal growth observation. For this purpose, we have developed the compact furnace which can be mounted on a goniometer used for the GIXD experiment. Using the custom-designed furnace, we have succeeded in controlling very high temperature around 1800°C. Subsequently, we have proved the performance of the furnace through the measurement of the tem- perature dependence of a-lattice constant of 4H-SiC in the range from room temperature to 1500 °C.
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Silva, Gonçalo M. C., Pedro Morgado, Pedro Lourenço, Michel Goldmann y Eduardo J. M. Filipe. "Spontaneous self-assembly and structure of perfluoroalkylalkane surfactant hemimicelles by molecular dynamics simulations". Proceedings of the National Academy of Sciences 116, n.º 30 (5 de julio de 2019): 14868–73. http://dx.doi.org/10.1073/pnas.1906782116.

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Fully atomistic molecular-dynamics (MD) simulations of perfluoroalkylalkane molecules at the surface of water show the spontaneous formation of aggregates whose size and topography closely resemble the experimentally observed hemimicelles for this system. Furthermore, the grazing incidence X-ray diffraction (GIXD) pattern calculated from the simulation trajectories reproduces the experimental GIXD spectra previously obtained, fully validating the MD simulation results. The detailed analysis of the internal structure of the aggregates obtained by the MD simulations supports a definite rational explanation for the spontaneous formation, stability, size, and shape of perfluoroalkylalkane hemimicelles at the surface of water.
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Tesis sobre el tema "Grazing incidence X-ray diffraction (GIXD)"

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Baudot, Sophie. "MOSFETs contraints sur SOI : analyse des déformations par diffraction des rayons X et étude des propriétés électriques". Phd thesis, Grenoble, 2010. http://tel.archives-ouvertes.fr/tel-00557963.

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L'introduction d'une contrainte mécanique dans le canal de MOSFETs sur SOI est indispensable pour les noeuds technologiques sub-22 nm. Son efficacité dépend de la géométrie et des règles de dessin du dispositif. L'impact des étapes du procédé de fabrication des transistors (gravure des zones actives, formation de la grille métallique, implantation des Source/Drain (S/D)) sur la contrainte du silicium contraint sur isolant (sSOI) a été mesuré par diffraction des rayons X en incidence rasante (GIXRD). Parallèlement, le gain en performances de MOSFETs sur sSOI a été quantifié par rapport au SOI (100% de gain en mobilité pour des nMOS longs et larges (L=W=10 μm), 35% de gain en courant de drain à saturation (IDsat) pour des nMOS courts et étroits (L=25 nm, W=77 nm)). Des structures contraintes innovantes ont aussi été étudiées. Un gain en IDsat de 37% (18%) pour des pMOS sur SOI (sSOI) avec des S/D en SiGe est démontré par rapport au sSOI avec des S/D en Si, pour une longueur de grille de 60 nm et des films de 15 nm d'épaisseur. Des mesures GIXRD, couplées à des simulations mécaniques, ont permis d'étudier et d'optimiser des structures originales avec transfert de contrainte d'une couche enterrée précontrainte (en SiGe ou en nitrure) vers le canal.
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Baudot, Sophie. "MOSFETs contraints sur SOI : analyse des déformations par diffraction des rayons X et étude des propriétés électriques". Phd thesis, Grenoble, 2010. http://www.theses.fr/2010GRENY064.

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L'introduction d'une contrainte mécanique dans le canal de MOSFETs sur SOI est indispensable pour les noeuds technologiques sub-22 nm. Son efficacité dépend de la géométrie et des règles de dessin du dispositif. L'impact des étapes du procédé de fabrication des transistors (gravure des zones actives, formation de la grille métallique, implantation des Source/Drain (S/D)) sur la contrainte du silicium contraint sur isolant (sSOI) a été mesuré par diffraction des rayons X en incidence rasante (GIXRD). Parallèlement, le gain en performances de MOSFETs sur sSOI a été quantifié par rapport au SOI (100% de gain en mobilité pour des nMOS longs et larges (L=W=10 μm), 35% de gain en courant de drain à saturation (IDsat) pour des nMOS courts et étroits (L=25 nm, W=77 nm)). Des structures contraintes innovantes ont aussi été étudiées. Un gain en IDsat de 37% (18%) pour des pMOS sur SOI (sSOI) avec des S/D en SiGe est démontré par rapport au sSOI avec des S/D en Si, pour une longueur de grille de 60 nm et des films de 15 nm d'épaisseur. Des mesures GIXRD, couplées à des simulations mécaniques, ont permis d'étudier et d'optimiser des structures originales avec transfert de contrainte d'une couche enterrée précontrainte (en SiGe ou en nitrure) vers le canal
The use of mechanical stress in the channel of MOSFETs on SOI is mandatory for sub-22 nm technological nodes. Its efficiency depends on the device geometry and design. The impact of different steps of the transistor fabrication process (active area patterning, metal gate formation, Source/Drain (S/D) implantation) on the strain in strained Silicon-On-Insulator (sSOI) materials has been measured by Grazing Incidence X-Ray Diffraction (GIXRD). The electrical performance enhancement of MOSFETs on sSOI has also been estimated with respect to SOI (100% mobility enhancement for long and wide nMOS (L=W=10 μm), 35% saturation drive current (IDsat) enhancement for short and narrow nMOS (L=25 nm, W=77 nm)). Innovative strained structures have then been studied. We demonstrate a 37% (18%) IDsat enhancement for pMOS on SOI (sSOI) with SiGe S/D compared to sSOI with Si S/D, for a 60 nm gate length and a 15 nm film thickness. GIXRD measurements, together with mechanical simulations, enabled the study and optimization of new structures using the stress transfer from an embedded and stressed layer (SiGe or nitride) toward the channel
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Jukes, Paul Christian. "Grazing incidence x-ray diffraction and neutron reflection studies of semi-crystalline polymer surfaces and interfaces". Thesis, University of Sheffield, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.251303.

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Satapathy, Dillip Kumar. "Molecular-beam epitaxy growth and structural characterization of semiconductor-ferromagnet heterostructures by grazing incidence x-ray diffraction". [S.l.] : [s.n.], 2005. http://deposit.ddb.de/cgi-bin/dokserv?idn=982680724.

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Satapathy, Dillip Kumar. "Molecular-beam epitaxy growth and structural characterization of semiconductor-ferromagnet heterostructures by grazing incidence x-ray diffraction". Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 2006. http://dx.doi.org/10.18452/15563.

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Diese Arbeit behandelt das Wachstum des ferromagnetischen Metalls MnAs auf halbleitendem GaAs. Die MnAs-Filme werden auf GaAs mittels der Molekularstrahlepitaxie (MBE) abgeschieden. Nukleation, Entwicklung von Gitterverzerrungen, Morphologie und Grenzflächenstruktur werden in-situ während des MBE Wachstums mit Hilfe von Beugung unter streifendem Einfall (GID) und der Beugung hochenergetischer Elektronen (RHEED) untersucht. Mit azimuthalen RHEED Messungen wurden vier Abschnitte des Nukleationsprozesses von MnAs auf GaAs(001) bestimmt. GID Messungen zeigen, dass das weitere Wachstum des MnAs Films bei einer nominellen Bedeckung von 2.5 ML über die Bildung relaxierter Inseln erfolgt, welche an Größe zunehmen und schließlich einen durchgängigen Film bilden. In einem Frühstadium bildet sich ein geordnetes Versetzungsnetzwerk an der Grenzfläche, welches die Verzerrungen aufgrund der Fehlanpassung bereits vor der vollständigen Ausbildung des durchgängigen Films abbauen. Der faszinierend komplexe Nukleationsprozess von MnAs auf GaAs(0 0 1) beinhaltet sowohl Elemente von Volmer-Weber, als auch von Stranski-Krastanov Wachstum. Die nicht einheitliche Gitterfehlanpassung beträgt 0.66% entlang der [1 -1 0] Richtung und 0.54% entlang der [1 1 0] Richtung, wie sich aus den Röntgenbeugungsmessungen ergibt. Entlang der [1 1 0] Richtung wird eine hohe Korrelation der Defekte beobachtet. Ein hochgradig periodisches Versetzungsnetzwerk mit einer Periode von 4.95 +- 0.05 nm entlang der [1 1 0] Richtung wird an der Grenzfläche gebildet und relaxiert 7.5% der Fehlanpassung. Die inhomogenen Verzerrungen aufgrund dieser periodischen Versetzungen an der Grenzfläche sind auf eine Schicht von 1.6nm Dicke beschränkt. Die Fehlanpassung entlang der [1 -1 0] Richtung wird durch die Bildung eines Koinzidenzgitters abgebaut.
The present work is devoted to the growth of the ferromagnetic metal MnAs on the semiconductor GaAs by molecular-beam epitaxy (MBE). The MnAs thin films are deposited on GaAs by molecular-beam epitaxy (MBE). Grazing incidence diffraction (GID) and reflection high-energy electron diffraction (RHEED) are used in situ to investigate the nucleation, evolution of strain, morphology and interfacial structure during the MBE growth. Four stages of the nucleation process during growth of MnAs on GaAs(001) are revealed by RHEED azimuthal scans. GID shows that further growth of MnAs films proceed via the formation of relaxed islands at a nominal thickness of 2.5 ML which increase in size and finally coalesce to form a continuous film. Early on, an ordered array of misfit dislocations forms at the interface releasing the misfit strain even before complete coalescence occurs. The fascinatingly complex nucleation process of MnAs on GaAs(0 0 1) contains elements of both Volmer-Weber and Stranski-Krastanov growth. A nonuniform strain amounting to 0.66%, along the [1 -1 0] direction and 0.54%, along the [1 1 0] direction is demonstrated from x-ray line profile analysis. A high correlation between the defects is found along the GaAs[1 1 0] direction. An extremely periodic array of misfit dislocations with a period of 4.95 +- 0.05 nm is formed at the interface along the [1 1 0] direction which releases the 7.5% of misfit. The inhomogeneous strain due to the periodic dislocations is confined at the interface within a layer of 1.6 nm thickness. The misfit along the [1 -1 0] direction is released by the formation of a coincidence site lattice.
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Scherzer, Michael [Verfasser], Robert [Akademischer Betreuer] Schlögl, Ullrich [Akademischer Betreuer] Pietsch, Robert [Gutachter] Schlögl, Ullrich [Gutachter] Pietsch y Thorsten [Gutachter] Ressler. "Grazing incidence X-ray diffraction : application on catalyst surfaces / Michael Scherzer ; Gutachter: Robert Schlögl, Ullrich Pietsch, Thorsten Ressler ; Robert Schlögl, Ullrich Pietsch". Berlin : Technische Universität Berlin, 2018. http://d-nb.info/1163661481/34.

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Joshi, Gaurav Ravindra. "Elucidating sweet corrosion scales". Thesis, University of Manchester, 2015. https://www.research.manchester.ac.uk/portal/en/theses/elucidating-sweet-corrosion-scales(12a5be22-14fc-4add-b48b-a372652f3471).html.

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The objective of this thesis is to improve understanding of the development of corrosion products (scales) that form on the inner walls of carbon steel pipelines in CO2-rich (sweet) oilfield environments. If well adherent to the carbon steel surface, such scales can significantly reduce the metal’s rate of corrosion. Typically, the open literature labels sweet corrosion scale as ferrous (II) carbonate (FeCO3) or siderite, although this may not always be the case. For example, Fe2(OH)2CO3 (chukanovite) and Fe3O4 (magnetite) are known to modify the protective character of a sweet corrosion product scale. Practical electrochemical methods for the assessment of substrate corrosion, and electron/photon-based characterisation techniques for investigating scale structure and composition, have revealed interesting aspects of the nature of sweet corrosion scale development on model high purity Fe and real-world pipeline steel surfaces. Concerning scale development on model Fe substrates immersed in CO2-saturated deionised water (buffered to pH = 6.8, T = 80°C, Ptotal = 1 bar), electrochemical data supplemented by grazing incidence x-ray diffraction (GIXRD) and scanning electron microscopy (SEM) show that a semi-protective mixed corrosion scale comprising siderite and chukanovite becomes a highly protective siderite scale with longer exposure time. The introduction of sodium chloride to the CO2-saturated solution (T = 80°C, pH = 6.8, Ptotal = 1 bar) impedes the rate of scale formation. Increasing [NaCl] from the start of experiment is suspected to limit the precipitation kinetics of sweet corrosion scale crystals, since chukanovite is no longer observed, and siderite formation is somewhat slowed as well. SEM imaging, using an electronic workfunction-sensitive detector (in lens), reveals nanoscale deposits on the corroded Fe surface in regions that are devoid of µm-scale crystals. With the Raman spectra from these regions considered, it is interpreted that the nanoscale deposits are likely amorphous iron carbonate, albeit oxidised to a significant extent. Moving to real-world carbon steel immersion in sweet solutions, a scale comprising predominantly chukanovite is observed (using GIXRD and SEM) on the 1% Ni weld zone (WZ) surface of a pipeline weld-joint, but not on adjacent, distinct regions (heat affected zones (HAZ) and base metal (BM)). This selective scaling is suggested to be due to some initial corrosion of the weld-joint, which generates sufficient [Fe2+(aq)], and a macro-galvanic effect across the weld, i.e. WZ is cathodic to HAZ and BM. Further, to gain mechanistic insight into compositional changes during sweet corrosion scale growth, an electrochemical cell for in situ GIXRD (named E-cell) has been developed and commissioned. Diffraction patterns acquired using synchrotron radiation, from a pipeline steel surface, reveal the formation and temporal evolution of a multicomponent corrosion scale. Accompanying electrochemical data suggest that the scale is quite protective.
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Gasperini, Antonio Augusto Malfatti 1982. "Estudo do processo de formação de nanopartículas de GeSi em matriz de sílica por técnicas de luz síncrotron". [s.n.], 2011. http://repositorio.unicamp.br/jspui/handle/REPOSIP/277863.

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Orientadores: Gustavo de Medeiros Azevedo, Ângelo Malachias de Souza, Eduardo Granado Monteiro da Silva
Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Fisica Gleb Wataghin
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Resumo: Neste trabalho estudamos a formação e estrutura de nanopartículas (NPs) de GeSi encapsuladas em sílica, utilizando técnicas baseadas em luz síncrotron, complementadas com imagens de microscopia eletrônica de transmissão. Obtivemos a forma, o diâmetro médio e a dispersão de tamanhos usando espalhamento de raios X a baixos ângulos em incidência rasante (GISAXS). A partir dos dados de difração de raios X (XRD) foi possível obter a fase cristalina, o parâmetro de rede e o tamanho médio dos cristalitos. Estes resultados serviram como dados de entrada em um modelo para análise através da técnica de estrutura fina de absorção de raios X (EXAFS), a qual forneceu informações sobre a estrutura local na vizinhança dos átomos de Ge. Apesar dos resultados de cada uma das técnicas acima serem comumente analisados de forma separada, a combinação destas técnicas leva a uma melhor compreensão das propriedades estruturais das NPs. Através da combinação dos resultados tivemos acesso a informações tais como a deformação da rede cristalina (strain), a fração de átomos cm ambientes cristalino e amorfo, a fração de átomos de Ge diluída na matriz e a possibilidade de formação de estruturas do tipo core-shell cristalino-amorfo. Resultados adicionais como a origem do strain e a temperatura de solidificação das NPs, dentre outros, foram obtidos através de um experimento in situ de absorção de raios X em energia dispersiva (DXAS), inédito na análise deste sistema. Por fim, utilizamos as técnicas acima citadas para acompanhar a evolução dos parâmetros estruturais em amostras tratadas termicamente durante diferentes intervalos de tempo
Abstract: In this work we study the formation and structure of GeSi nanoparticles embedded in silica matrix using synchrotron-based techniques complemented by TEM images. Shape, average diameter and size dispersion were obtained from grazing incidence small angle X-ray scattering. X-ray diffraction measurements were used to obtain crystalline phase, lattice parameter and crystallite mean sizes. By using these techniques as input for extended X-ray absorption fine structure analysis, the local structure surrounding Ge atoms is investigated. Although the results for each of the methods mentioned above are usually analyzed separately, the combination of such techniques leads to an improved understanding of nanoparticle structural properties. Crucial indirect parameters that cannot be quantified by other means are accessed in our work, such as local strain, possibility of forming core-shell crystalline-amorphous structures, fraction of Ge atoms diluted in the matrix and amorphous and crystalline Ge fraction. Additional results as the origin of the strain and temperature of solidification of NPs, among others, were obtained through an in situ energy dispersive X-ray absorption experiment (DXAS), unheard in this system. Finally, we use the techniques mentioned above to monitor the evolution of the structural parameters of samples annealed during different time intervals
Doutorado
Física
Doutor em Ciências
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Gilles, Bruno. "Etude par rayons X rasants des effets de l'implantation de silicium dans le silicium et de fer dans un grenat". Grenoble 2 : ANRT, 1986. http://catalogue.bnf.fr/ark:/12148/cb37597890r.

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Robach, Odile. "Étude in situ de la croissance de Ag sur MgO(001) et de Ni/Ag(001), et étude de la nitruration du GaAs par diffusion de rayons X en incidence rasante". Université Joseph Fourier (Grenoble ; 1971-2015), 1997. http://www.theses.fr/1997GRE10226.

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Un nouvel instrument est presente, qui permet l'elaboration d'interfaces dans une chambre ultra-vide et l'etude in situ de leur structure et de leur morphologie par diffusion des rayons x en incidence rasante (dxir). Il est installe sur la ligne de lumiere crg/if d32 de l'esrf. Une nouvelle description du mode de croissance de l'ag sur le mgo est proposee, dans laquelle, des 0. 2 monocouches (mc) d'ag deposees, le depot est sous forme d'ilots et la majorite de l'ag est relaxee. La signification physique de la fraction en site de l'ag est discutee, ainsi que les possibilites de calcul des positions atomiques dans un ilot d'ag deforme par les contraintes d'epitaxie dues au mgo. La preparation de surfaces de mgo bien adaptees aux etudes par dxir est decrite. Les phases presentes dans differents depots de ni sur ag (001) ont ete identifiees et caracterisees. A tous les montants de depots de 1 a 20 mc, trois phases coexistent : du ni en site, du ni (001) relaxe et du ni (011) 4h, qui forment des colonnes s'etendant jusqu'a la surface du depot. Une rugosification de l'ag liee au depot de ni a ete mise en evidence, ainsi que de fortes deformations de l'ag. La nitruration a l'aide d'une source d'azote a resonance cyclotron electronique (ecr) des surfaces (001) et (-1-1-1)b du gaas a ete etudiee. Pour former une couche de gan d'epaisseur bien definie il est preferable de separer la phase d'implantation des atomes d'azote dans le gaas de la phase de recuit declenchant la formation du gan. Des developpements de la technique d'analyse sont presentes, qui concernent en particulier les calculs de resolution instrumentale et l'analyse des donnees de diffusion aux petits angles en incidence rasante.
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Libros sobre el tema "Grazing incidence X-ray diffraction (GIXD)"

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Flom, Erik B. Studies of the liquid-vapor interfaces of gallium and bismuth-gallium using grazing incidence x-ray diffraction. 1993.

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Deshpande, U. P., T. Shripathi y A. V. Narlikar. Iron-oxide nanostructures with emphasis on nanowires. Editado por A. V. Narlikar y Y. Y. Fu. Oxford University Press, 2017. http://dx.doi.org/10.1093/oxfordhb/9780199533053.013.23.

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This article examines the properties of iron-oxide nanostructures, with particular emphasis on nanowires. It begins with an overview of iron-oxide nanostructures and nanowires, followed by a discussion of the synthesis of aligned ?-Fe2O3 nanowires and nanosheets by a simple thermal oxidation route. It then describes the preferential bending of [110] grown ?-Fe2O3 nanowires about the C-axis and quantitative estimation of nanowire alignment using X-ray diffraction and grazing incidence X-ray diffraction. It also considers the growth mechanism of ?-Fe2O3 nanowires and nanosheets, different nanowire morphologies, rotational slip in ?-Fe2O3 nanosheets, and the influence of local environment and substrate microstructure on nanowire growth.
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Capítulos de libros sobre el tema "Grazing incidence X-ray diffraction (GIXD)"

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Ballard, B. L., P. K. Predecki y D. N. Braski. "Stress-Depth Profiles in Magnetron Sputtered Mo Films Using Grazing Incidence X-ray Diffraction (Gixd)". En Advances in X-Ray Analysis, 189–96. Boston, MA: Springer US, 1994. http://dx.doi.org/10.1007/978-1-4615-2528-8_25.

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Predecki, Paul, X. Zhu y B. Ballard. "Proposed Methods for Depth Profiling of Residual Stresses using Grazing Incidence X-Ray Diffraction (GIXD)". En Advances in X-Ray Analysis, 237–45. Boston, MA: Springer US, 1993. http://dx.doi.org/10.1007/978-1-4615-2972-9_28.

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Sakata, Osami y Masashi Nakamura. "Grazing Incidence X-Ray Diffraction". En Surface Science Techniques, 165–90. Berlin, Heidelberg: Springer Berlin Heidelberg, 2013. http://dx.doi.org/10.1007/978-3-642-34243-1_6.

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Takahara, Atsushi y Yuji Higaki. "X-Ray and Neutron Reflectivity and Grazing Incidence X-Ray Diffraction". En Molecular Soft-Interface Science, 129–39. Tokyo: Springer Japan, 2019. http://dx.doi.org/10.1007/978-4-431-56877-3_8.

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Garbauskas, Mary F., Donald G. LeGrand y Raymond P. Goehner. "Application of Grazing Incidence X-Ray Diffraction to Polymer Blends". En Advances in X-Ray Analysis, 373–77. Boston, MA: Springer US, 1993. http://dx.doi.org/10.1007/978-1-4615-2972-9_42.

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Huang, T. C. "Surface and Ultra-Thin Film Characterization by Grazing-Incidence Asymmetric Bragg Diffraction". En Advances in X-Ray Analysis, 91–100. Boston, MA: Springer US, 1990. http://dx.doi.org/10.1007/978-1-4613-9996-4_10.

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Stabenow, Rainer y Alfried Haase. "New Tools for Grazing Incidence Diffraction Measurements: Comparison of Different Primary and Secondary Beam Conditioners". En Advances in X-Ray Analysis, 87–94. Boston, MA: Springer US, 1997. http://dx.doi.org/10.1007/978-1-4615-5377-9_11.

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Müller-Buschbaum, P. "A Basic Introduction to Grazing Incidence Small-Angle X-Ray Scattering". En Applications of Synchrotron Light to Scattering and Diffraction in Materials and Life Sciences, 61–89. Berlin, Heidelberg: Springer Berlin Heidelberg, 2009. http://dx.doi.org/10.1007/978-3-540-95968-7_3.

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Prévot, Geoffroy. "Direct Measurement of Elastic Displacement Modes by Grazing Incidence X-Ray Diffraction". En Mechanical Stress on the Nanoscale, 275–97. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2011. http://dx.doi.org/10.1002/9783527639540.ch13.

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Schamper, C., D. Dornisch, W. Moritz, H. Schulz, R. Feidenhans’l, M. Nielsen, F. Grey y R. L. Johnson. "Au Adsorption on Si(111) Studied by Grazing Incidence X-Ray Diffraction". En Springer Proceedings in Physics, 17–20. Berlin, Heidelberg: Springer Berlin Heidelberg, 1992. http://dx.doi.org/10.1007/978-3-642-77144-6_4.

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Actas de conferencias sobre el tema "Grazing incidence X-ray diffraction (GIXD)"

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Clemens, B. M., A. P. Payne, T. C. Hufnagel, J. A. Bain y S. Brennan. "In-Situ Grazing Incidence X-Ray Diffraction During Sputter Deposition". En Physics of X-Ray Multilayer Structures. Washington, D.C.: Optica Publishing Group, 1992. http://dx.doi.org/10.1364/pxrayms.1992.wa4.

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Many aspects of thin film growth can be studied most directly using in-situ techniques. These include a host of critical phenomena which are only observed for very thin layers and are no longer available for study if the film is grown to bulk levels. Although sputter deposition is a very widely used deposition technique both in research and industry, in-situ studies of film growth during sputter deposition are rare. This is primarily because the sputtering gas precludes the use of conventional electron diffraction techniques. Photon based diffraction techniques, on the other hand, are immune to the deleterious effects of the argon sputtering gas and offer a powerful method for investigating film structure provided a source of sufficient brightness is used. We recently performed experiments in which grazing incidence x-ray scattering (GIXS)[1] using synchrotron radiation was implemented in-situ to study film growth by sputter deposition . A special UHV deposition chamber was developed with appropriate x-ray windows and precision sample positioning mechanisms needed in performing a diffraction experiment [2]. During the initial test of this new technique and apparatus, we examined two metal/metal systems: gadolinium/cobalt and molybdenum/nickel.
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Burlacov, I., R. B. Heimann y M. Müller. "Correlation of Plasma Process Conditions, Phase Content, and Photocatalytic Performance of Induction Plasma-Sprayed Titania Coatings". En ITSC2005, editado por E. Lugscheider. Verlag für Schweißen und verwandte Verfahren DVS-Verlag GmbH, 2005. http://dx.doi.org/10.31399/asm.cp.itsc2005p1160.

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Abstract Systematic variation of the induction plasma spray (IPS) conditions, i.e. (i) plasma power, (ii) carrier gas flow rate, and (iii) powder feed rate was performed to deposit TiO2 coatings using statistical design of experiments (SDE) methodology. The microstructure, surface morphology, and anatase-rutile ratio of the coatings were studied by grazing-incidence X-ray diffraction (GIXD) and surface mapping with micro-probe Raman spectroscopy to determine the spatial phase distribution of anatase and rutile. The photocatalytic activity of the TiO2 coatings was tested by decomposition of 4-chlorophenol in aqueous solution in the dark and under UV irradiation. The rates of pH changes measured were compared with those of standard Degussa P-25 coatings. The photocatalytic activity of the samples shows a reasonable correlation with the phase content and the plasma processing conditions prevailing during coating deposition.
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Chen, Yu-Chen, Wen-Kai Chen, Jing-Chi Huang y Jia-Yang Juang. "Deposition of Highly Transparent and Conductive Films on Tilted Substrates by Atmospheric Pressure Plasma Jet". En ASME 2019 28th Conference on Information Storage and Processing Systems. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/isps2019-7423.

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Abstract We study the influence of the substrate tilt angle on the microstructure and optoelectronic properties of gallium-doped zinc oxide (GZO) thin films deposited by the atmosphere pressure plasma jet (APPJ) method. The nozzle trajectories play a key role in oblique angle deposition. In the process of oblique angle deposition, if the nozzle scanned from the upstream side to the downstream side, the electrical properties such as resistivity, carrier concentration and mobility deteriorate considerably. The optical properties also worsen — specular transmittance goes down and diffuse transmittance increase to a significant amount. This degradation can be attributed to the “pre-deposition” of the GZO adsorbed particles (ad-particles) on the downstream side of the raw glass where the nozzle has not scanned. These GZO ad-particles serve as nuclei on which the incoming vapor particles deposit preferentially. Scanning electron microscopy (SEM), and grazing incidence X-ray diffraction (GIXRD confirmed that the film near the downstream is thicker, less smooth, and porous than that near the upstream. The undesirable situation can be mitigated or even completely removed via proper nozzle scanning trajectories — reversing the scanning trajectory of the nozzle. If the nozzle scans from the downstream side to the upstream side, no pre-deposition of the GZO ad-particles to deteriorate the film properties and therefore the obliquely deposited films perform as well as the films deposited without tilt, i.e. flat substrate. This work presents a solution to the challenge of depositing TCO on tilted and curved surfaces.
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Goray, Leonid I., Alexander S. Dashkov, Viktor E. Asadchikov, Boris S. Roshchin, Arsen E. Muslimov y Vladimir M. Kanevsky. "Grazing-incidence X-ray reflectometry and fluorescence analysis of the metallic-coated sinusoidal diffraction grating". En 2019 Days on Diffraction (DD). IEEE, 2019. http://dx.doi.org/10.1109/dd46733.2019.9016515.

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Imamov, Rafik M., O. G. Melikyan y Dmitry V. Novikov. "Control and characterization of semiconductor superlattices by grazing: incidence x-ray diffraction method". En International Conference on Microelectronics, editado por Andrzej Sowinski, Jan Grzybowski, Witold T. Kucharski y Ryszard S. Romaniuk. SPIE, 1992. http://dx.doi.org/10.1117/12.131045.

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Zhang, Yan, Fan Qichao, Li Jiawei, Zhang Hui, Huabin He, Chao Wang, Wei Gao y Ji Fang. "The using of x-ray grazing incidence diffraction technique in KDP surface characterization". En Advanced Fiber Laser Conference (AFL2022), editado por Pu Zhou. SPIE, 2023. http://dx.doi.org/10.1117/12.2666983.

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Omi, H., T. Kawamura, Y. Kobayashi, S. Fujikawa, Y. Tsusaka, Y. Kagoshima y J. Matsui. "Inhomogeneous strain in thin silicon films analyzed by grazing incidence x-ray diffraction". En 2006 International Conference on Solid State Devices and Materials. The Japan Society of Applied Physics, 2006. http://dx.doi.org/10.7567/ssdm.2006.i-8-3.

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Watanabe, K., Y. Kimura y K. Mukai. "Grazing Incidence X-ray Diffraction Measurements of Columnar InAs/GaAs Quantum-Dot Structures". En 2009 International Conference on Solid State Devices and Materials. The Japan Society of Applied Physics, 2009. http://dx.doi.org/10.7567/ssdm.2009.h-1-8.

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Tarrio, C., R. D. Deslattes, A. Caticha y J. Pedulla. "Trends in the X-Ray Diffraction of Multilayers". En Physics of X-Ray Multilayer Structures. Washington, D.C.: Optica Publishing Group, 1994. http://dx.doi.org/10.1364/pxrayms.1994.tua.4.

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Understanding the morphology of multilayer structures (MLS's) is an important step toward the preparation of high-quality multilayer mirrors for use in the extreme ultraviolet. To gain information about the structure, the x-ray reflectivity is measured at grazing angles. These data are then analyzed using any of a number of models to gain information about such characteristics as d spacing, spacing uniformity, heavy element fill factor (Γ), and diffusion boundary widths. Several models have been used with varying degrees of success to describe the x-ray diffraction of multilayers. The matrix method, in which the reflectivity is explicitly calculated at each interface, is exact for abrupt interfaces, but to include diffusion it is necessary to divide each boundary into many layers, which slows the calculations considerably. Traditional x-ray diffraction models allow for rapid calculations, but make approximations that are not generally applicable to multilayers. The kinematical model, in which only one reflection is allowed within the sample, is only accurate for low reflectivities, and thus is not valid near the Bragg peaks of the MLS. The dynamical model allows for multiple reflections, but is not accurate away from Bragg peaks at grazing incidence.
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Villoresi, P., E. Jannitti, P. Nicolosi, M. Perin y G. Tondello. "A Facility for the Measurement of the Soft X-ray Reflectivity Spectrum of XUV and Soft X-ray Mirrors". En Physics of X-Ray Multilayer Structures. Washington, D.C.: Optica Publishing Group, 1994. http://dx.doi.org/10.1364/pxrayms.1994.tuc.2.

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The spectrally resolved reflectivity coefficient of multilayer mirrors is measured in the EUV-soft X-ray spectral region. A laser produced plasma (LPP) acts as a bright source of continuous spectrum radiation, and it is used to light the multilayer mirror under test. The reflected rays are collected by a grazing incidence toroidal mirror and focused in the entrance slit of a grazing incidence spectrograph, where the spectrum is detected. The ratio of such spectrum with that obtained with the direct collection of the LPP spectrum, corrected for the higher diffraction orders contributions, is the spectrum of the absolute reflectivity coefficient for the mirror[1].
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Informes sobre el tema "Grazing incidence X-ray diffraction (GIXD)"

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Jones, L. Ruthenium-Platinum Thin Film Analysis Using Grazing Incidence X-ray Diffraction. Office of Scientific and Technical Information (OSTI), septiembre de 2004. http://dx.doi.org/10.2172/833117.

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Fritz, S. Structural Characterization of a pentacene monolayer on an amorphous SiO2 substrate with grazing incidence x-ray diffraction. Office of Scientific and Technical Information (OSTI), febrero de 2004. http://dx.doi.org/10.2172/826751.

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