Global existence of smooth solutions to 2D Chaplygin gases on curved space

This paper investigates the smooth solution of 2D Chaplygin gas equations on an asymptotically flat Riemannian manifold. Under the assumption that the initial data are close to a constant state and the vorticity of the initial velocity vanishes, we prove the global existence of smooth solutions to the Cauchy problem for two‐dimensional flow of Chaplygin gases on curved space. Copyright © 2016 John Wiley & Sons, Ltd.     

制革工业中的绿色化学与技术

论述了中国制革工业研究和实施绿色化学与技术的重要性。概述了国内外在绿色皮革化学品的开发和应用, 清洁的制革生产以及制革废弃物利用方面的研究成果, 并提出了今后的发展方向。     

荧光探针技术在高分子科学中的应用

本文从原理及应用两个方面介绍了荧光探针技术在高分子科学中的应用, 讨论了荧光探针化合物的光化学和光物理行为, 以及如何用该技术来研究高分子的结构特征和高分子体系的动态过程问题, 包括利用该技术来研究高分子体系中的分子运动、能量转移和自由体积等重要例证。     

关于广义拟einstein流形

近年来,不少研究都涉及到Ricci张量R_(αβ)能写成的黎曼流形,如[1]—[3]等。当一个黎曼流形(M,α)满足(1),且其中ξ为单位向量时,Adati等称该M为ξ-Einstein流形。显然,这类流形的性质不如Einstein流形。因此,专门研究这类流形的文献还不多见。上述各引文与[5]讨论的均为其特别情形。不难知道,白正国教授在[6]中研究的流形也属于此。为和具有类似于形式(1)的其它相应流形的名称(如“拟脐”,“拟常曲率”等)相一致,作者在[7]中称满足(1)的M为拟Einstein的。并简记为QE(ξ)流形,而称ξ为基本元。在那里,我们得到了这类流形的几何特征和Weyl张量满足的代数特征,并指出了某些QE流形的不存在性。本文的目的则是探讨当(1)中ξ是迷向向量场时相应流形的有关性质。     

OU型Markov过程常返性判别的一个充分条件

研究ＯＵ型Ｍａｒｋｏｖ过程的常返、暂留性．给出了判断ＯＵ型Ｍａｒｋｏｖ过程常返的一个简单实用的充分条件，说明了Ｌｅｖｙ过程Ａｔ的暂留性不能必然地导致由它生成的ＯＵ型Ｍａｒｋｏｖ过程的暂留性．     

Recurrence formulas for molecular integrals over Laguerre Gaussian-type functions

Recurrence formulas for overlap, nuclear attraction, and electron-repulsion integrals over Laguerre Gaussian-type functions are presented. They have been derived using compact recurrence relations for homogeneous solid spherical harmonic operators but are rather lengthy as compared to those over Cartesian Gaussian-type functions. © 1998 John Wiley & Sons, Inc. Int J Quant Chem 66 : 273–279, 1998     

3类图完美匹配的数目

图的完美匹配计数问题是匹配理论研究中的一个重要课题,此问题有很强的物理学和化学背景．但是,一般图的完关匹配计数问题却是NP-困难的．用划分、求和、再递推的方法给出了三类特殊图完美匹配数目的计算公式．     

随机环境中马氏链的常返性和瞬时性

讨论了随机环境马氏链中具有强π不可约性链的常返性的判定,从而得到了强π不可约链常返性判定的充分必要条件,同时给出了在一定条件下随机环境中的马氏链的瞬时性判定的几个充分条件.     

基于Samelson逆的向量值连分式的收敛准则

The aim of this work is to give some criteria on the convergence of vector valued continued fractions defined by Samelson inverse. We give a new approach to prove the convergence theory of continued fractions. First, by means of the modified classical backward recurrence relation, we obtain a formula between the m-th and n-th convergence of vector valued continued fractions. Second, using this formula, we give necessary and sufficient conditions for the convergence of vector valued continued fractions.     

Rational approximations of the Arrhenius integral using Jacobi fractions and gaussian quadrature

The aim of this work is to find approaches for the Arrhenius integral by using the n-th convergent of the Jacobi fractions. The n-th convergent is a rational function whose numerator and denominator are polynomials which can be easily computed from three-term recurrence relations. It is noticed that such approaches are equivalent to the one established by the Gauss quadrature formula and it can be seen that the coefficients in the quadrature formula can be given as a function of the coefficients in the recurrence relations. An analysis of the relative error percentages in the approximations is also presented.