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991.
An existence theorem for the variational problem for the two-phase medium energy functional is proved. Dependence of the solution on the surface tension coefficient and on the temperature is investigated. Bibliography: 7 titles. Dedicated to V. A. Solonnikov on his sixtieth anniversary Translated fromZapiski Nauchnykh Seminarov POMI, Vol. 213, 1994, pp. 131–150. Translated by S. Yu. Pilyugin.  相似文献   
992.
An iterative method from the class of completely implicit methods (CIM) is proposed for solving the equation of the velocity potential of elliptical-hyperbolic type. The advantage of the proposed method compared to other CIM schemes is demonstrated in application to mixed perfect gas flows in a nozzle of a given shape. Accuracy issues, rate of convergence, and various techniques of ensuring stability in the hyperbolic region are discussed. Translated from Chislennye Metody v Matematicheskoi Fizike, Published by Moscow University, Moscow, 1996, pp. 39–51.  相似文献   
993.
This paper justifies the necessity of introducing corrections for the ray curvature into the standard procedure of the tomographic inversion in the case of using traveltime data for the creeping waves. The results of relevant numerical experiments are presented. Bibliography: 3 titles. Translated fromZapiski Nauchnykh Seminarov POMI, Vol. 218, 1994, pp 67–71. This work was supported by the Russian Foundation of Fundamental Research (Grant 93-05-9961). Translated by A. P. Krauklis.  相似文献   
994.
995.
This paper continues the investigation about the singularity theory in dual rich quasi–Banach spaces given in T. Runst [Ru 2]. The abstract results are applied to the study of the solution structure of semilinear elliptic boundary value problems in spaces of Besov – Triebel – Lizorkin type.  相似文献   
996.
997.
We construct a correspondence between the set of partitions of a finite set M and the set of pairs of walks to the same vertex on a graph giving the Bratteli diagram of the partition algebra on M. This is the precise analogue of the correspondence between the set of permutations of a finite set and the set of pairs of Young tableaux of the same shape, called the Robinson–Schensted correspondence.  相似文献   
998.
Fe(II)--Fe(III) hydroxy-chloride, -sulphate and -carbonate were prepared by oxidation of a ferrous hydroxide precipitate in anion-containing aqueous solutions. The compounds are characterized by monitoring the redox potential Eh and the pH of stochiometric suspension vs time with the appropriate concentration ratios. X-ray diffraction allows us to characterize the crystal structure by distinguishing “green rust one” (GR1) from “green rust two” (GR2). Since green rusts (GRs) are of a pyroaurite-sjögrenite-like structure, i.e., consisting of intercalated foreign anions and water molecules in the interlayers between the brucite-like layers of Fe(OH)2, their chemical formulae can be determined from the Mössbauer spectra. Three quadrupole doublets are observed: D1 and D2 correspond to a ferrous state with isomershift IS of about 1.27 mm s-1 and quadrupole splittings QS of about 2.85 and 2.60 mm s-1, respectively, whereas D3 corresponds to a ferric state with IS and QS of about 0.4 mm s-1. The hyperfine parameters of these doublets are similar from one green rust to another but their intensity ratios vary considerably. Finally, Eh and pH equilibrium diagrams of the Fe species in the presence of chloride, sulphate and carbonate anions contained within the water solution are drawn and the thermodynamic conditions of existence and degrees of oxidation of green rusts are discussed.  相似文献   
999.
用准相对论扭曲波方法系统地计算了Ba、Nd、Gd、Yb、Au、Pb类铜离子组态能级之间的电子碰撞激发强度Ω(nl-nl),3≤n≤7,4≤n≤7,同时给出了高能极限的碰撞强度和外推到阈值的碰撞强度,用最小二乘样条方法拟合了全能域碰撞强度及热平均速率系数。对于一个激发过程,用10个参数可以得到碰撞电子在任意能量下的碰撞强度以及任意温度下的速率系数。  相似文献   
1000.
Methods of synthesizing previously unknown derivatives of coumarin — 2-(N-R-imino)-2H-1-benzopyrans, where R = Alk, Ar — are proposed. Possibilities of alternative synthetic schemes are discussed, and hypotheses concerning probable mechanisms of the reactions are formulated.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 760–766, June, 1994. Original article submitted May 23, 1994.  相似文献   
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