Navegação Ciências Exatas e da Terra por Assunto "Difração de raios X"
Resultados 21-40 de 40
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Spatial separation of vacancy and interstitial defects formed in Si by oxygen-ion irradiation at elevated temperature
(2005) [Artigo de periódico]A study of damage depth distribution in Si by elevated temperature O+-ion implantation was performed using three structures: (i) bulk Si, (ii) Si/SiO2 /bulk Si, and (iii) SiO2 /bulk Si. The samples were implanted at 250°C ... -
Strain development and damage accumulation during neon ion implantation into silicon at elevated temperatures
(2000) [Artigo de periódico]The development of mechanical strain and accumulation of damage in silicon single crystals implanted with Ne ions to doses in the range of 0.1–1.0 x1017 cm-² at temperatures from 200 to 600 °C were investigated employing ... -
Structural and magnetic behavior of ar+-implanted co/pd multilayers : interfacial mixing
(1994) [Artigo de periódico]The magnetization behavior of Co/Pd multilayers has been analyzed as a function of the degree of interfacial mixing among the Co and Pd layers. Controlled atomic mixing was induced by low-dose and low-flux ion implantation ... -
Structural and Mössbauer characterization of the ball-milled Fe/sub x/(Al/sub 2/O/sub 3)/sub 100-x/ system
(2004) [Artigo de periódico]Metal-oxide composites were synthesized by high-energy ball milling of metallic iron (α-Fe) and alumina (α-Al2O3) powders, varying the starting relative concentration and the milling time. The samples were characterized ... -
Structural and spectroscopic investigation of the charge-ordered, short-range ordered, and disordered phases of the Co3O2BO3 ludwigite
(2021) [Artigo de periódico]Charge ordering is prone to occur in crystalline materials with mixed-valence ions. It is presumably accompanied by a structural phase transition, with possible exceptions in compounds that already present more than one ... -
Structural change and heteroepitaxy induced by rapid thermal annealing of CaF/sub 2/ films on Si(111)
(1998) [Artigo de periódico]In this article we show that heteroepitaxial CaF2 films can be induced on Si~111! with a rapid thermal anneal. The change from preferentially oriented polycrystals to a single crystal with type- B epitaxy is visible by ... -
Structural changes of fe precipitates in annealed fe-al/sub 2/o/sub 3/ films
(1999) [Artigo de periódico]We report on the structural changes of Fe-AI203 films deposited - both co-evaporated and multilayered samples - at room temperature and subsequently annealed at 400"C during 5h. Our results suggest that the Fe precipitates ... -
Structural characterization of the Co/sub 2/FeZ(Z=Al, Si, Ga, and Ge) Heusler compounds by x-ray diffraction and extended x-ray absorption fine structure spectroscopy
(2007) [Artigo de periódico]This work reports on the structure of Fe containing, Co2-based Heusler compounds that are suitable for magnetoelectronic applications. The compounds Co2FeZ where Z=Al, Si, Ga, and Ge were investigated using the x-ray ... -
Structural, microstructural and magnetic characterization of the β-CoTe nanophase synthesized by a novel mechanochemical method
(2021) [Artigo de periódico]This work reports an unprecedented mechanochemistry synthesis of β-CoTe and its systematic characterization through X-ray powder diffraction (XRPD), transmission electron microscopy (TEM), and magnetometry techniques. The ... -
Structural modifications in FexCo1-x/Cu multilayers induced by ion irradiation
(2004) [Artigo de periódico]The structural evolution of Fe30Co70 /Cu multilayers under ion irradiation is investigated in detail using x-ray techniques. The samples were irradiated with two different ions, 50 keV of He+ and 600 keV of Kr+, at room ... -
Structure, microstructure and magnetic investigation of the hexagonal d-FeSe nanophase produced by mechanochemical synthesis
(2020) [Artigo de periódico]We present a systematic structural, microstructural and magnetic characterization of the hexagonal d-FeSe nanophase produced by a simple one-step mechanochemical synthesis route, by using conventional X-ray powder diffraction ... -
A study of the structural, magnetic, and electrical properties of Ba1-xNaxCoO3 compounds (x = 0.25, 0.5, 0.75)
(2021) [Artigo de periódico]Cobaltite-like materials having metal-insulator transitions are relevant in the consumer electronics market. In this work, we present the structural, magnetic, and electrical properties of Ba1-xNaxCoO3(with x= 0.25, 0.5, ... -
Surface morphology of spray-dried nanoparticle-coated microparticles designed as an oral drug delivery system
(2008) [Artigo de periódico]This paper was devoted to studying the influence of coating material (nanocapsules or nanospheres), drug model (diclofenac, acid or salt) and method of preparation on the morphological characteristics of nanoparticle-coated ... -
The epitaxial growth of evaporated cu/caf2 bilayers on si(111)
(1995) [Artigo de periódico]Successful and unexpected epitaxial growth of Cu/CaF2, bilayers on hydrogen terminated Si(111) wafers by thermal evaporation is reported. The bilayers were characterized with conventional x-ray diffraction experiments, ... -
The influence of nitrogen to hydrogen ratio and temperature on thickness and phase composition in plasma nitrided Ti-6Al-4V
(2019) [Artigo de periódico]Ti-6Al-4V was plasma nitrided using several N2/H2 ratios and substrate temperatures. In order to investigate the combined influence of these parameters on phase compositionand thickness of the coatings,the phases in the ... -
Tuning anatase-rutile phase transition temperature : TiO2/SiO2 nanoparticles applied in dye-sensitized solar cells
(2019) [Artigo de periódico]TiO2/SiO2 nanoparticles with 3, 5, and 10 molar percent of silica, were synthesized by hydrothermal method and characterized by SEM, TEM, N2 adsorption-desorption isotherms, X-ray diffraction, and Raman and UV-Vis spectroscopy. ... -
Ultrafast trapping times in ion implanted InP
(2002) [Artigo de periódico]As+ and P+ implantation was performed on semi-insulating (SI) and p-type InP samples for the purpose of creating a material suitable for ultrafast optoelectronic applications. SI InP samples were implanted with a dose of ... -
Unraveling structural and compositional information in 3D FinFET electronic devices
(2019) [Artigo de periódico]Non-planar Fin Field Effect Transistors (FinFET) are already present in modern devices. The evolution from the well-established 2D planar technology to the design of 3D nanostructures rose new fabrication processes, but a ... -
Valence and delocalization of yb in the Chevrel-phase YbMo 6 S 8
(1983) [Artigo de periódico]Mãssbauer isomer-shift measurements show that Yb is divalent in YbMo6Sg. The asymmetry of the Yb thermal vibration at 4.2 K obtained from the Goldanskii-Karyagin effect is much smaller than that obtained from a Rietveld ... -
X-ray-absorption spectroscopy and x-ray diffraction in discontinuous Co/sub x/Fe/sub 1-x//Ag multilayers
(2000) [Artigo de periódico]This paper reports on the structural properties of CoxFe12x /Ag discontinuous multilayers with x 50, 0.3, 0.7, and 1. The evolution of the structural properties has been investigated by x-ray diffraction and x-ray-absorption ...