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1.
2.
The main phase transformations during synthesis of β‐sialon from kaolin of the Prosyanovskii deposit (Ukraine) under test-industrial production conditions have been studied. Sialon was prepared by carbothermal reduction in graphite-tube furnaces in nitrogen. It is shown that the process is characterized by the simultaneous occurrence of several chemical reactions with formation of intermediate phases (Si2ON2, X1‐phase), silicon carbide, and (apart from β‐sialon) sialons based on AlN polytypes. The phase composition of the final product is determined not only by the charge composition but also by the set of production parameters. Results of the work may provide a basis for commercial preparation of sialon powder. 相似文献
3.
A. A. Aliev A. V. Suetina A. V. Elistratov A. D. Davydov A. G. Rakhshtadt 《Metal Science and Heat Treatment》2007,49(1-2):75-77
The effect of tempering temperature on the structure, wear resistance, and corrosive properties of steel 08Kh14AN4MDB is studied.
The results of mechanical and corrosion tests are used for constructing an optimization matrix for determining the optimum
tempering temperature.
__________
Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 2, pp. 29–32, February, 2007. 相似文献
4.
A method for determining the concentration and electron-impact excitation cross section of activated emission centers in the phosphor layer of a thin-film electroluminescent capacitor structure, based on measurements of the brightness as a function of the applied alternating voltage amplitude and frequency, is analyzed. The error of determination of the parameters of electroluminescence excited by alternating-sign ramp voltage is evaluated. The parameters of electroluminescent structures based on the ZnS:Mn, ZnS:TbF3, and ZnS:SmF3 films are presented. 相似文献
5.
6.
A. A. Lebedev A. M. Strel’chuk D. V. Davydov N. S. Savkina A. N. Kuznetsov L. M. Sorokin 《Technical Physics Letters》2002,28(9):792-794
The electrical characteristics of (p)3C-SiC-(n)6H-SiC epitaxial heterostructures obtained by sublimation epitaxy in vacuum are studied. The band discontinuities are determined and the energy band diagram of the heterojunction is constructed. It is shown that the obtained heterostructure offers a promising material for high electron mobility transistors. 相似文献
7.
8.
E. Ya. Davydov I. S. Gaponova T. V. Pokholok G. B. Pariiskii G. E. Zaikov 《应用聚合物科学杂志》2008,108(1):128-133
The features of initiation of free radical reactions in polymers by dimers of nitrogen dioxide are considered. The conversion of planar dimers into nitrosyl nitrate in the presence of amide groups of macromolecules has been revealed. Nitrosyl nitrate initiates radical reactions in oxidative primary process of electron transfer with formation of intermediate radical cations and nitric oxide. As a result of subsequent reactions, nitrogen‐containing radicals are produced. The dimer conversion has been exhibited by estimation of the oxyaminoxyl radical yield in characteristic reaction of p‐benzoquinone with nitrogen dioxide on addition of aromatic polyamide and polyvinylpyrrolidone to reacting system. The isomerization of planar dimers is efficient in their complexes with amide groups, as confirmed by ab initio calculations. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
9.
We have studied the effect of spontaneous polarization, which is inherent in noncubic silicon carbide (SiC) polytypes, on the characteristics of quantum wells (QWs) formed in the cubic region at the heterojunction. The analysis is performed for various QW models, including triangular, parabolic, and exponential. Conditions for the appearance of a two-dimensional electron gas at the interface are briefly discussed. 相似文献
10.
A population balance method in which continuum and discrete phases are integrated is developed to simulate the evolution of polydisperse population of bubbles in a turbulent pipeline flow. The investigation is focused on the effect of the coalescence efficiency on this evolution. A dilute system of bubbles under microgravity conditions is considered. It is found that if the initial coalescence efficiency is low, a slight increase produces a significant effect on the bubble coalescence rate, and thus on the evolution of the population. If, however, the initial coalescence efficiency is high, its increase results in a marginal effect on the way the population evolves. The results of simulations are validated against experimental data on the population mean. 相似文献