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161.
A simple simulation scheme that simultaneously describes the growth kinetics of SiO2 films at the nanometer scale and the SiOx/Si interface dynamics (its extent, and spatial/temporal evolution) is presented. The simulation successfully applies to experimental data in the region above and below 10 nm, reproduces the Deal and Grove linear-parabolic law and the oxide growth rate enhancement in the very thin film regime (the so-called anomalous region). According to the simulation, the oxidation is governed mainly by two processes: (a) the formation of a transition suboxide layer and (b) its subsequent drift towards the silicon bulk. We found that it is the superposition of these two processes that produces the crossover from the anomalous oxidation region behavior to the linear-parabolic law. 相似文献
162.
F. Iachello S. Oss 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2002,19(3):307-314
We present a brief review of algebraic techniques developed and applied in molecular spectroscopy in the last five years.
We also outline perspectives for new applications of the Lie algebraic method in the first decade of the new century.
Received 21 November 2001 相似文献
163.
Several 5-substituted derivatives of 7-ethoxycarbonyl-6,8-dimethyl-1(2H)- phthalazinone were prepared by means of nitration, reductive amination, and diazonium decomposition. The substituents introduced included NO2, NH2, F, Cl, CN. Among the derivatives, the fluorine compound was obtained only in poor yield because intramolecular cyclization occurred predominantly. 相似文献
164.
Purification and some properties of squalene-2,3-epoxide: lanosterol cyclase from rat liver 总被引:1,自引:0,他引:1
Squalene-2,3-epoxide: lanosterol cyclase was purified from rat liver in five steps as a soluble and homogeneous protein. The purified enzyme showed a single band on SDS-polyacrylamide gel electrophoresis with a molecular weight of 75 kD. In its native state it behaved as a homo-dimer. The isoelectric point of 5.5 and the apparent Km value for (3S)-squalene-epoxide of 55 microM were estimated for the cyclase. 相似文献
165.
F. S. de Aguiar L. B. Bernardes S. Goulart Rosa Jr. 《Journal of statistical physics》1991,64(3-4):673-682
Metastability in the ferromagneticp-state Potts model defined on the Cayley tree is discussed. It is shown that the sign of the boundary fieldH
s
determines the order of the transition as well as the stability of the low-temperature phase. Lowering the temperature withH
s
>0, a system withp<2 (p>2) will display a second (first)-order transition to a metastable (stable) phase. ForH
s
>0 a second (first)-order transition to a metastable (stable) phase occurs ifp>2 (p<2). In this case the system also has a residual entropy which is negative forp<2. 相似文献
166.
R. F. Bikbaev 《Journal of Mathematical Sciences》1991,57(3):3078-3083
Diffraction by a semitransparent screen is considered in the framework of the nonlinear Schrödinger equation. The case of a defocusing medium is investigated. The method used represents a synthesis of the method of Riemann's matrix problem and the technique of Whitham's deformations of spectral curves.Translated from Zapiski Nauchnykh Seminarov Leningradskogo Otdeleniya Matematicheskogo Instituta im. V. A. Steklova, Vol. 179, pp. 23–31, 1989. 相似文献
167.
Under idealized conditions, electroconvection in a nematic liquid crystal sets in at a well-defined threshold of the driving ac voltage. Fluctuating convection rolls of a small amplitude below that threshold have been observed recently. The measurement of the amplitude of these fluctuations is described in detail in this paper. It is based on averaging the light intensity signals using the structure function and a quantitative analysis of the light deflection. 相似文献
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