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81.
Using the method of jump functions, we solve the antiplane problem of elasticity theory for a stack of anisotropic strips containing plane band-type inhomogeneities. We model these inclusions by jumps of the stress vector and the derivative of the displacement vector at the middle surfaces. Applying the Fourier integral transformation, we obtain the dependence of the components of the stress tensor and displacement vector on the external load and unknown jump functions. Taking into account the conditions of the interaction between a thin inclusion and an anisotropic medium, we reduce the problem to a system of singular integral equations for the jump functions. A specific example is considered as well. 相似文献
82.
The main achievement of this paper is that we show, what was to us, a surprising conclusion, namely, twice continuously differentiable
functions in (0,1) (with some regular behavior at the endpoints) which change monotonicity at least once in the interval, are approximable
better by comonotone polynomials, than are such functions that are merely monotone. We obtain Jackson-type estimates for the
comonotone polynomial approximation of such functions that are impossible to achieve for monotone approximation.
July 7, 1998. Date revised: May 5, 1999. Date accepted: July 23, 1999. 相似文献
83.
Dr. Matthias Müller M. Sc. Steffen Maier Olena Tverskoy Dr. Frank Rominger Dr. Jan Freudenberg Prof. Uwe H. F. Bunz 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(5):1982-1985
In combination with bulky substituents at the core, fourfold benzannulation at the cata-positions stabilizes a nonacene sufficiently to allow its isolation and characterization by 1H NMR and X-ray analysis. The four benzo units blueshift the absorption spectrum in comparison to a solely linear nonacene, but significantly increase the stability in the solid state. 相似文献
84.
Alla G. Dyachenko Galyna G. Tsapyuk Snizhana V. Gaidai Olena V. Ischenko Tetiana M. Zakharova Galyna D. Il'nitskaya 《Molecular Crystals and Liquid Crystals》2020,701(1):91-97
AbstractIn this article, we present the preparation, characterization, and catalytic performance of bimetallic Co93Fe07 and Ni80Fe20 active mass loaded on synthetic nanodiamonds (SNDs) in the carbon dioxide (CO2) methanation. The pristine SNDs possessing a developed specific surface are thermally stable and inert to the reaction mixture of CO2 and dihydrogen. However, it is shown that 100% conversion of CO2 into methane can be reached at the lower temperature than that for a massive Co93Fe07 or Ni80Fe20 catalyst when 20?wt.% of the catalyst mass was loaded on the surface of SNDs. The catalytic activity of the prepared bimetallic/SNDs composites is estimated as the minimum temperature at the maximum conversion of CO2 at atmospheric pressure: it is 325 and 290?°C for Co93Fe07/SNDs and Ni80Fe20/SNDs, respectively. Thermal desorption studies showed that the methanation over Co-Fe/SNDs and Ni-Fe/SNDs catalysts run through the stage of CO2 dissociation into carbon and oxygen atoms and their subsequent interaction with hydrogen to form methane and water molecules. Scanning electron microscopy studies have shown that the presence of transition metal-rich sites on the surface of the carrier contributes to the improvement of efficiency of the Ni80Fe20 catalyst action. 相似文献
85.
We propose a method of computing the corrosion process under a covering in neutral electrolytes. From the corrosion rate found we determine the variation in the adhesion and stressed state of the coverings.Translated fromMatematicheskie Metody i Fiziko-Mekhanicheskie Polya, Issue 27, 1988, pp. 45–51. 相似文献
86.
Translated from Ukrainskii Matematicheskii Zhurnal, Vol. 41, No. 4, pp. 441–454, April, 1989. 相似文献
87.
88.
A. A. Tolmachev V. S. Tolmacheva L. I. Shevchuk F. S. Babichev 《Chemistry of Heterocyclic Compounds》1992,28(10):1130-1134
Methods have been developed for the synthesis from amino-substituted indolines of first linear trinuclear hetaryl-condensed2-methyleneindolines having quinolone, quinoline, quinoxaline, and benzmidazole fragments. The structure of the obtained compounds was confirmed by 1H and 13C NMR spectra.For communication 3, see [1]Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1331–1335, October, 1992. 相似文献
89.
90.
V. S. Tolmacheva A. V. Kropachev A. Yu. Il'chenko A. A. Tolmachev L. I. Shevchuk F. S. Babichev 《Chemistry of Heterocyclic Compounds》1992,28(12):1382-1384
Methods were developed to convert 1,2,3,3-tetramethyl-6-hydroxyindoline into coumarin dyes, in which the amino group is in the indoline system. The structure of the products was indicated by 1H and 13C NMR spectroscopy.Communication 4, see ref. [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1614–1616, December 1992. 相似文献