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991.
概率赋范空间中的非线性半群与微分包含* 总被引:1,自引:0,他引:1
本文的目的是在概率赋范空间中引入和研究非线性压缩半群,并对增生映象建立Crandal-Ligget指数公式.作为应用,我们将应用这些结果研究概率赋范空间中一类具增生映象的微分包含的Cauchy问题解的存在性. 相似文献
992.
993.
S. Marais Q. T. Nguyen C. Devallencourt M. Metayer T. U. Nguyen P. Schaetzel 《Journal of Polymer Science.Polymer Physics》2000,38(15):1998-2008
The diffusion and permeation properties of liquid water through different polar and nonpolar polymers and copolymers were studied with a highly sensitive permeameter. The transient permeation fluxes through the polar polymer films could be fitted well only with an exponential equation for the diffusivity concentration dependence; this empirical exponential equation represented the diffusion plasticization effect of water on the materials. For the hydrophobic polyolefins, this exponential equation was no longer valid, and another form of the equation was empirically found to account for the reduction of the water diffusivity with the extent of the permeation. Such a negative plasticization effect might be attributed to the formation of water clusters in the polyolefins. The values of the diffusion coefficient of water in the dry polar polymers were smaller than those in dry polyolefins, but the opposite behavior was found for the permeability because it was much more favorable for water sorption in the polar polymers than in the hydrophobic polyolefins. For the ethylene–vinylacetate copolymers, the plasticization effect of water on its own diffusion was negative for the sample with a low vinyl acetate (VA) content; it became nil at 19 wt % VA and positive at higher VA contents. This increase in the extent of the water sorption with the increase in the VA content led to a steady increase in the water permeability in the poly(ethylene‐co‐vinylacetate) copolymers. © 2000 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 38: 1998–2008, 2000 相似文献
994.
J. Fernndez Rico R. Lpez A. Aguado I. Ema G. Ramírez 《International journal of quantum chemistry》2001,81(2):148-153
A new program for computing all the integrals appearing in molecular calculations with Slater‐type orbitals (STO) is reported. This program follows the same philosophy as the reference pogram previously reported but introduces two main changes: Local symmetry is profited to compute all the two‐electron integrals from a minimal set of seed integrals, and a new algorithm recently developed is used for computing the seed integrals. The new code reduces between one and two orders of magnitude the computational cost in most polyatomic systems. © 2001 John Wiley & Sons, Inc. Int J Quant Chem 81: 148–153, 2001 相似文献
995.
The stretched exponential relaxation modulus of regular and polymer modified asphalts is studied. It is shown that this relaxation function can generate the dynamic functions of these materials very well on any finite interval of the reduced frequencies (master curves). By continuation one can, in principle, cover the whole region of master curves of G′ and G″. The dispersive defect diffusion mechanism, which leads to the stretched exponential law, points to the stronger three-dimensional structure of modified asphalt at low temperatures. The method of calculating G′ and G″ from the stretched exponential relaxation modulus is proposed and tested on one regular and one modified asphalt. © 1997 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 35 : 1225–1232, 1997 相似文献
996.
997.
In this paper, we prove that the mixed norm for an exponential type weighted integral of an entire function is equivalent to the mixed norm of its radial derivative and the distortion function from the weight function in the n-dimensional complex space. 相似文献
998.
Bahtiyar A. Mamedov 《International journal of quantum chemistry》2014,114(5):361-366
This article, written on behalf of Guseinov's friends and colleagues in honor of his 80th birthday, presents a brief biography and an overview of the major themes of his scientific researches. This is an opportunity to summarize Guseinov's main contributions to the quantum theory of atoms, molecules, and nuclei. Some aspects of Guseinov's career and research are highlighted here. © 2013 Wiley Periodicals, Inc. 相似文献
999.
《Mathematical Methods in the Applied Sciences》2018,41(12):4776-4794
Our aim in this paper is to study the asymptotic behavior, in terms of finite‐dimensional attractors, for higher‐order Navier‐Stokes‐Cahn‐Hilliard systems. Such equations describe the evolution of a mixture of 2 immiscible incompressible fluids. We also give several numerical simulations. 相似文献
1000.
张小明 《高校应用数学学报(A辑)》2002,17(4):401-410
运用一些分析技巧 ,讨论纯量周期差分微分方程x(t) =a(t) x(t) +b(t) x(t- kω)的解 ,其中 a(t) ,b(t)是以ω为周期的连续周期函数 ,k为某自然数 .得到了该方程具有趋于零快于任何指数但最终不恒等于零的解的充分必要条件 .同时给出解的具体的表达式 相似文献