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1.
Thermoelastic contact interaction of bodies in the presence of surface thermophysical irregularities
We study the thermoelastic contact interaction (in the absence of friction) of half-spaces under conditions of planar deformation in the presence of thin surface thermophysical irregularities that are taken into account by means of generalized conditions of thermal contact with one another. The problem is reduced to solving a system of singular integrodifferential equations with respect to the jumps of temperature and heat flow on the boundary of a section. We analyze the influence of a nonuniform thermal resistance distributed periodically along the surface or localized in one region of it on the distribution of temperature and stresses in the bodies and on their boundary. Four figures.Translated fromMatematicheskie Metody i Fiziko-Mekhanicheskie Polya, Issue 27, 1988, pp. 23–28. 相似文献
2.
Numerical calculations are carried out within the framework of the ideal compressible gas model for the unsteady flows in rectangular cavities exposed to a supersonic external stream. The Euler equations are integrated by means of Godunov's finite-difference method [6]. On the basis of an analysis of the calculation results an expression is proposed for determining the possible frequencies of the flow rate oscillations in the cavity as a function of the free-stream Mach number M and the geometry of the cavity. The results obtained are compared with the experimental data and calculations of other authors.Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 2, pp. 121–127, March–April, 1990. 相似文献
3.
Alexei Yu. Lukin Sergei V. Shevyakov Alexei V. Laptev Olga I. Davydova Vitali I. Shvets Olga V. Demina Yury P. Strokach Valery A. Barachevsky Michail V. Alfimov Sergei P. Gromov Artem I. Vedernikov Johan Lugtenburg Andrey A. Khodonov 《Journal of inclusion phenomena and macrocyclic chemistry》2004,49(1-2):153-161
An effective synthetic approach to the preparation of a new crown-ether vinylogs involving the Horner–Emmons olefination of carbonyl precursors with the use of C2- and C5-phosphonates was proposed. The effects of the conjugation chain length and the nature of the terminal polar functions in the phosphonate reagent on the yield and process stereoselectivity were discussed. 相似文献
4.
5.
T. I. Denisova D. I. Shvets T. G. Shramkova M. F. Kovtun 《Russian Journal of Applied Chemistry》2007,80(1):53-57
Sorption of Cu(II), Pb(II), Cd(II), and Zn(II) from aqueous solutions on two-component organosilicas was studied as influenced by sorbent composition, contact time, ratio of solid and liquid phases, solution pH, nature and concentration of heavy metal ions, and content of modifying agent. The degrees of sorption of these metal ions from aqueous solutions using organosilicas modified with aluminum(III) added into the siloxane matrix or with copper(II) grafted to the sorbent surface layer were compared. 相似文献
6.
One of the methods of designing aircraft with supersonic flight speeds involves solving an inverse problem by means of the well-known flow schemes and the substitution of rigid surfaces for the flow surfaces. Lifting bodies using the flows behind axisymmetric shock waves belong to these configurations. All lifting bodies using the flow behind a conical shock wave can be divided into two types [1]. Bodies whose leading edge passes through the apex of the conical shock wave pertain to the first type and those whose leading edge lies below the apex of the conical shock wave, to the second. For small apex angles of the basic cone at hypersonic flow velocities an approximate solution of the variation problem was obtained, which showed that the lift-drag ratio of lifting bodies of the second type is higher than that of the first [2]. The present paper gives a numerical solution of the problem for flow past lifting bodies of the second type using the flow behind axisymmetric conical shock waves with half-angles of the basic cone S=9.5 and 18° The upper surfaces of the bodies are formed by intersecting planes parallel to the velocity vector of the oncoming flow.Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 2, pp. 135–138, March–April, 1986. 相似文献
7.
A. V. Luk'yanov A. I. Lyutik V. I. Shvets N. A. Preobrazhenskii 《Chemistry of Natural Compounds》1966,1(4):185-187
Summary 1. The methyl ester of N-(N-carbobenzoyglycyl)-methoxyneuraminic acid has been synthesized by the carbodiimide method.2. Hydrogenation of the methyl ester of N-(N-carbobenzoxyglycyl)-methoxyneuraminic acid over Pb/BaSO4 has given the methyl ester of N-glycyl-methoxyneuraminic acid.Khimiya Prirodnykh Soedinenii, Vol. 1, No. 4, pp. 241–244, 1965 相似文献
8.
Peculiarities of bitemplate synthesis of a homologous series of organosilica mesophases (precursors of mesoporous molecular sieves of MCM-41 type) were studied, and an influence of a nature of templating substances and a solubilization on a perfection of their spatial structure was found. n-alkyl(C8–C18)pyridinium halides as solubilizers (micelle-forming surfactants) and monoethanolamides of saturated n-(C10–C16)aliphatic acids as solubilizate were used. Some physicochemical factors promoting a spatial ordering of organosilica mesophases and mesoporous molecular sieves were considered. 相似文献
9.
10.
R. K. Alekseenko L. S. Ivanova D. I. Shvets 《Theoretical and Experimental Chemistry》1991,26(6):694-697
In order to establish the interrelation between the electronic characteristics of carbons that are manifested in the EPR spectra and their ability to adsorb complex gold and silver ions, the EPR spectra of carbon adsorbents from phenol-formaldehyde resins of various nature, unactivated and activated under various conditions, and the adsorption of [Au(CN)2]– and [Ag(CN)2]– from cyanide solutions on these same adsorbents were investigated. A parallel relation was observed between the amount of paramagnetic centers on carbon and its adsorption capacity and selectivity in relation to these anions.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 26, No. 6, pp. 742–745, November–December, 1990. 相似文献