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91.
92.
We discuss the electronic properties of non-polar surfaces of MgN rock-salt and zinc-blende crystals. We studied the (001) surface of the rock-salt and the (110) surface of the zinc-blende MgN with the use of an ab initio full-electron linearized augmented plane wave method within density functional theory. The structural parameters of the two surfaces were optimized by relaxing the position of the atoms in the unit cells in the force directions. The results of the calculations indicate that both rock-salt MgN (001) and ZB MgN (110) demonstrate half-metallic properties. The zinc-blende MgN (110) surface is electronically more stable as a half-metal than the rock-salt MgN (001) surface. The magnetic properties of the two systems are tailored mainly by the spin-polarization of electrons of N atoms. 相似文献
93.
We consider stationary linear vector systems with commensurable delays. We obtain sufficient conditions for the reducibility of such systems to canonical form with the extraction of null dynamics. A constructive algorithm for the reduction of a system to that form is presented. We suggest a method for estimating the unknown input for vector delay systems with given accuracy. 相似文献
94.
N. G. Samoilenko B. L. Korsunskii V. A. Bostandzhiyan A. V. Il’ichev L. V. Kustova 《Russian Journal of Physical Chemistry B, Focus on Physics》2016,10(6):973-977
The characteristics of a thermal explosion in an ideal mixing batch reactor charged with a liquid–solid heterogeneous system are studied. The reactor initially contains both phases. The solid reagent dissolves and reacts in the liquid phase. A strong dependence of the critical value of the Semenov parameter on the dimensionless time of complete dissolution of the solid reagent is established. It is shown that, at short times of complete dissolution, the critical value of the Semenov parameter is practically independent on this time, and the thermal explosion occurs as in a homogeneous system, according to Semenov theory. The heterogeneous properties of the reaction system manifest themselves only at long times of complete dissolution. 相似文献
95.
R. V. Cherbunin M. S. Kuznetsova I. Ya. Gerlovin I. V. Ignatiev Yu. K. Dolgikh Yu. P. Efimov S. A. Eliseev V. V. Petrov S. V. Poltavtsev A. V. Larionov A. I. Il’in 《Physics of the Solid State》2009,51(4):837-840
The spin orientation dynamics in a GaAs quantum well with a laterally nonuniform electric potential generated by a mosaic electrode deposited on the surface of the sample has been investigated using the photoinduced magneto-optical Kerr effect. It has been found that the application of a negative potential higher than 1 V to the electrode leads to more than a hundredfold increase in the spin polarization lifetime in the sample under study. It is concluded that so strong slowing down of the relaxation is caused by a combined action of two effects, namely, the spatial separation of electron and hole, which reduces the radiative recombination rate of electron-hole pair, and the localization of electron, which is accompanied by the suppression of spin relaxation processes caused by electron motion. 相似文献
96.
E. P. Svidritskii M. Sh. Jiang V. I. Il’in D. I. Dyn’kov A. V. Pirogov O. A. Shpigun 《Moscow University Chemistry Bulletin》2010,65(1):42-48
A procedure for simultaneous determination of alendronate, chloride, phosphite, phosphate, and methylsulphonate anions is
proposed. These ions are the main admixtures in synthetic alendronic acid, and their content should be controlled when producing
pharmaceutical preparations of alendronic acid. The developed method makes it possible to determine all the indicated ions
over a period of 4 min. Excellent efficiency (200000–500000 theoretical plates) makes it possible to determine ions even with
a high content of one of the components. The detection limits are 0.4−2.3 mg/l. The developed method has been successfully
applied for the analysis of methanesulfonic acid regenerated from the reaction mixture. 相似文献
97.
Sorption of substituted indoles on highly cross-linked polystyrene from water-acetonitrile solutions
R. V. Shafigulin A. A. Myakishev E. A. Il’ina M. M. Il’in V. A. Davankov A. V. Bulanova 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2011,85(7):1216-1221
The sorption of first synthesized indole derivatives by highly cross-linked polystyrenes from water-acetonitrile solutions
was studied by high-performance liquid chromatography. The retention factors and differences in the Gibbs energy of adsorption
from infinite diluted solutions were calculated, and the applicability of the Snyder-Soczewinski and Scott-Kucera models for
describing the chromatographic retention of sorbates on a polymer network of highly cross-linked polystyrene was shown. 相似文献
98.
99.
Doklady Mathematics - 相似文献
100.
In terms of requirements imposed on the boundary function, we obtain a necessary and sufficient condition for the generalized solution of a mixed problem for the wave equation with zero initial conditions and with boundary conditions of the first kind to belong to the class L p . 相似文献