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81.
Variable temperature (−55 to −150°C) studies of the infrared spectra (3500 to 400 cm−1) of dimethylmethoxyphosphine, (CH3)2POCH3 and dimethyl(methylthio)phosphine, (CH3)2PSCH3 dissolved in liquid krypton and/or xenon have been recorded. From these data, the enthalpy differences have been determined to be 393±50 cm−1 (4.71±0.60 kJ/mol), for (CH3)2POCH3 with the near-cis conformer the more stable rotamer and 80±10cm−1 (0.96±0.12 kJ/mol) for (CH3)2PSCH3 with the cis conformer the more stable form. Complete vibrational assignments are presented for both molecules, which are consistent with the predicted frequencies obtained from the ab initio MP2/6-31G(d) calculations. The optimized geometries, conformational stabilities, harmonic force fields, infrared intensities, Raman activities, and depolarization ratios have been obtained from RHF/6-31G(d) and/or MP2/6-31G(d) ab initio calculations. These quantities are compared to the corresponding experimental quantities when appropriate as well as with some corresponding results for some similar molecules. 相似文献
82.
Vladimir P. Korzhik 《Discrete Mathematics》1998,190(1-3):149-162
The author has proposed methods of constructing index 2 and 3 current graphs generating triangular embeddings of graphs Kn−Km with unboundedly large m (as n increases). As a result, triangular embeddings of graphs of many families of graphs Kn−Km with unboundedly large m were constructed. The paper gives a survey of these results and a short explanation of the methods. 相似文献
83.
We first prove a quantitative estimate of the volume of the sublevel sets of a plurisubharmonic function in a hyperconvex domain with boundary values 0 (in a quite general sense) in terms of its Monge–Ampère mass in the domain. Then we deduce a sharp sufficient condition on the Monge–Ampère mass of such a plurisubharmonic function φ for exp(−2φ) to be globally integrable as well as locally integrable. 相似文献
84.
Masafumi Yoshino 《Annali di Matematica Pura ed Applicata》2008,187(4):555-562
We study a C
∞-Liouville-integrable and analytic non-integrable Hamiltonian system. We will show that an irregular singular character plays
a crucial role in the analytic non-integrability of the system.
Partially supported by Grant-in-Aid for Scientific Research (No. 11640183), Ministry of Education, Science and Culture, Japan. 相似文献
85.
在偏微分方程Riemann解法和微分方程裂变思想的启发下,引入了微分方程乘子函数(解)和乘子解法的概念,系统地讨论了二阶线性微分方程的乘子可积性.得到了二阶线性微分方程乘子可积的条件以及Riceati方程可积的充分必要条件,并分别给出了二阶线性微分方程和Riccati方程在乘子解下的通积分. 相似文献
86.
87.
During the last years both Erd?s space and complete Erd?s space were topologically characterized by Dijkstra and van Mill. Applications include results about Erd?s type spaces in ?p-spaces as well as results about Polishable ideals on ω. We present an unifying theorem in terms of sets with a reflexive relation that among other things contains these apparently dissimilar results as special cases. 相似文献
88.
该文建立了Hersch-Pfluger偏差函数ψK(r)和第二类完全椭圆积分ε(r)之间的关系. 通过对完全椭圆积分及某些初等函数的组合的单调性和凹凸性的研究获得了完全椭圆积分的一些不等式, 并且藉此得到Hersch-Pfluger偏差函数ψK(r)的几个渐进精确的上界估计. 相似文献
89.
90.
Weighted majority games have the property that players are totally ordered by the desirability relation (introduced by Isbell in [J.R. Isbell, A class of majority games, Quarterly Journal of Mathematics, 7 (1956) 183–187]) because weights induce it. Games for which this relation is total are called complete simple games. Taylor and Zwicker proved in [A.D. Taylor, W.S. Zwicker, Weighted voting, multicameral representation, and power, Games and Economic Behavior 5 (1993) 170–181] that every simple game (or monotonic finite hypergraph) can be represented by an intersection of weighted majority games and consider the dimension of a game as the needed minimum number of them to get it. They provide the existence of non-complete simple games of every dimension and left open the problem for complete simple games. 相似文献