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991.
Naoyuki Takahashi Arei Niwa Takato Nakamura 《Journal of Physics and Chemistry of Solids》2004,65(7):1259-1263
Indium nitride prepared under atmospheric pressure using a halide chemical vapor deposition method has been examined by means of a variety of analytical techniques. Scanning electron microscopic observations showed that the crystals deposited onto a Si(100) substrate have hexagonal pillar structure. Based on the X-ray diffraction and X-ray pole-figure analyses, it was deduced that each InN pillar crystal grows with a different rotation angle around the 〈001〉 axis. Transmission electron diffraction showed that they are of single-like form. This was also confirmed by the selected area electron diffraction image as well. 相似文献
992.
Research on the underpotential deposition of H (upd H) and anion adsorption on Pt( 100) in 0.5 M aqueous H2SO4 solution by cyclic voltammetry (CV) indicates that the overall adsorption/desorption charge density is affected strongly by variation of the temperature T, and that it decreases by about 1/3 when T is raised from 293 to 328 K. The sharp peak at 0.375 V vs. RHE assigned to the anion adsorption decreases its potential, current density and charge density. The CV feature assigned to the upd H, a wide shoulder overlapping the sharp peak, also decreases with T augmentation, but the decline of its charge density is less pronounced. The results indicate that the Hupd and anion surface coverages, θHAN and θAN respectively are strongly temperature-dependent. This behavior may be assigned to lateral repulsive interactions. 相似文献
993.
Annamária Mikó Ernő Kuzmann Magda Lakatos-Varsányi Attila Kákay Ferenc Nagy Lajos Károly Varga 《Hyperfine Interactions》2005,165(1-4):195-201
57Fe conversion electron Mössbauer spectroscopy, X-ray diffraction, electrochemical and magnetic measurements were used to study pulse electroplated Fe–P and Ni–Fe coatings. XRD and 57Fe CEMS measurements revealed the amorphous character of the novel pulse plated Fe–P alloys. CEM spectra indicated significant differences in the short range order and in the magnetic anisotropy between the Fe–P deposits pulse plated at medium long deposition time (t on?=?2 ms), with short relaxation time (t off?=?9 ms) and low current density (I p?=?0.05 Acm?2) or at short deposition time (t on?=?1 ms) with long relaxation time (t off?=?250 ms) and high current density (I p?=?1.0 Acm?2). The broad peaks centred around the fcc reflections in XRD of the pulse plated Ni-22 wt.% Fe deposit reflected a microcrystalline Ni–Fe alloy with a very fine, 5–8 nm, grain size. The CEM spectrum of the pulse plated Ni-22 wt.% Fe coating corresponded to a highly disordered solid solution alloy containing a minute amount of ferrihydrite. Extreme favourable soft magnetic properties were observed with these Ni–Fe and Fe–P pulse plated thin layers. 相似文献
994.
995.
F Maury 《应用有机金属化学》1992,6(8):619-626
Many organochromium compounds have been used as volatile chromium sources to prepare chromium-based coatings by chemical vapor deposition. Chromium carbides, nitrides, oxides and alloys have been deposited on different substrates at low temperature (<500 °C). Organochromium precursors are reviewed and some of their draw-backs are discussed. They are classified according to the nature of the chromium-ligand bonds (carbonyls, amides, arenes or alkyls). Furthermore, experimental results obtained in the same apparatus for a series of representative precursors are reported to discuss, with literature data, how the ligand affects the composition and the structure of the films. 相似文献
996.
采用脉冲激光沉积技术制备了钴纳米薄膜,分析和讨论了不同背景气压和脉冲频率对钴纳米薄膜表面形貌的影响及纳米微粒的形成机理。实验结果表明:在低背景气压下,等离子体羽辉自身粒子之间的碰撞占主导作用,容易形成液滴;在较高背景气压下,等离子体羽辉边缘粒子和背景气体粒子之间的碰撞占主导作用,容易形成小岛并凝聚成微颗粒;在4Hz的脉冲重复频率和5Pa背景气压下生长出单分散性良好的钴纳米颗粒。 相似文献
997.
P.G. Karlsson J.H. Richter M.P. Andersson J. Blomquist H. Siegbahn P. Uvdal A. Sandell 《Surface science》2005,580(1-3):207-217
Metal–organic chemical vapour deposition growth of titanium oxide on moderately pre-oxidised Si(1 1 1) using the titanium(IV) isopropoxide precursor has been studied for two different growth modes, reaction-limited growth at 300 °C and flux-limited growth at 500 °C. The interfacial properties have been characterized by monitoring synchrotron radiation excited Si 2p photoemission spectra. The cross-linking from oxidised Si to bulk Si after TTIP exposure has been found to be very similar to that of SiOx/Si(1 1 1). However, the results show that the additional oxidation of Si most probably causes a corrugation of the SiOx/Si interface. Those conclusions are valid for both growth modes. A model is introduced in which the amorphous interface region is described as (TiO2)x(SiO2)y where x and y changes linearly and continuously over the interface. The model quantifies how (TiO2)x(SiO2)y mixing changes the relative intensities of the signals from silicon oxide and silicon. The method can be generalised and used for the analyses of other metal-oxides on silicon. 相似文献
998.
The morphology of and electron tunneling through single and cluster cytochrome c molecules deposited on self-assembled dodecanthiol monolayer film on a gold substrate have been studied experimentally using scanning tunneling microscopy (STM) and scanning tunneling spectroscopy. STM images of a single cytochrome c molecule revealed a globular structure with a diameter of 4 nm and height of 1.5 nm. A spectroscopic study obtained by recording tunneling current–bias voltage (V–I) curves revealed that the STM current increases stepwise at asymmetric threshold sample bias voltages of +100 mV and –200 mV. 相似文献
999.
S. Arvelakis F. J. Frandsen E. G. Koukios 《Journal of Thermal Analysis and Calorimetry》2007,88(3):769-774
The ash material generated from the MSW incineration contains large amounts of alkali metals, heavy metals, chlorine and sulfur
mainly deposited as inorganic salts and/or oxides on the surface of the Si-rich ash particles. In this work, the composition
and gas-phase release characteristics of salt material extracted from MSW ash particles using a six-stage leaching process
is studied using simultaneous thermal analysis (STA). The produced results provide useful information regarding the composition
of the salt material and its melting behavior that is considered to play an important role to deposition and corrosion problems
at MSW incinerators. The results may be used to model the deposition process and to the better understanding of the corrosion
process during MSW incineration. 相似文献
1000.