检索结果-南通市图书馆

Two sufficient conditions for non-normal Cayley graphs and their applications

在线全文

学校读者我要写书评

暂无评论

Science China Mathematics 2007年第2期50卷 201-216页

作者： Jin-xin ZHOU Yan-quan FENG Department of Mathematics Beijing Jiaotong UniversityBeijing 100044China

A Cayley graph Cay(G, S) on a group G is said to be normal if the right regular representation R(G) of G is normal in the full automorphism group of Cay(G, S). In this paper, two sufficient conditions for non-normal Cayley graphs are given and by using the conditions, five infinite families of connected non-normal Cayley graphs are constructed. As an application, all connected non-normal Cayley graphs of valency 5 on A 5 are determined, which generalizes a result about the normality of Cayley graphs of valency 3 or 4 on A 5 determined by Xu and Xu. Further, we classify all non-CI Cayley graphs of valency 5 on A 5, while Xu et al. have proved that A 5 is a 4-CI group.

关键词： Cayley graph normal Cayley graph arc-transitive graph 05C25 20B25

A DFT INVESTIGATION OF THE MECHANISM FOR ALTERNATINGCOPOLYMERIZATION OF STYRENE WITH CARBON MONOXIDE CATALYZED BY Pd(Ⅱ) COMPLEXES

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2012年第5期30卷 744-758页

作者： Zi-dan Zhang 何学浩 Shi-chun Jiang Department of Polymer Science and Engineering School of Chemical Engineering and TechnologyTianjin UniversityTianjin300072China Department of Chemistry School of ScienceTianjin UniversityTianjin300072China School of Material Science&Engineering Tianjin UniversityTianjin300072China

Density functional theory has been employed to study the homogeneous catalytic copolymerization of styrene with carbon monoxide. The copolymerization reaction is catalyzed by Pd（II） coordinated with 2,2＇-bipyridine, a conventional nitrogen-containing bidentate ligand with achiral C2v symmetry. The chain propagation mechanism for the alternating copolymerization as well as the side reactions, including multiple insertions of CO and homopolymerization of styrene, has been investigated. This study focused exclusively on regioisomerism and stereoisomerism. We have demonstrated that the strictly alternating copolymerization is kinetically and thermodynamically favored over the side reactions （i.e., multiple insertions of CO and homopolymerization of styrene）. The regiochemistry study indicates the 2,1 type. Furthermore, the stereochemistry study shows that the syndiotactic conformation is preferred over the isotactic or atactic conformations.

关键词： DFT CO Styrene Polyketone Mechanism.

GLOBAL L^p ESTIMATES FOR THE PARABOLIC EQUATION OF THE BI-HARMONIC TYPE

在线全文

学校读者我要写书评

暂无评论

Journal of Partial Differential Equations 2008年第4期21卷 315-334页

作者： Yao Fengping Zhou Shulin Department of Mathematics Shanghai University Shanghai 200444 China LMAM School of Mathematical Sciences Peking University Bejing 100871 China

In this paper similarly to the second-order case, we give an elementary and straightforward proof of global Lp estimates for the initial-value parabolic problem of the bi-harmonic type. Moreover, we obtain the existence and uniqueness of the solutions in the suitable space using the potential theory, Marcinkiewicz interpolation theorem and approximation argument. Meanwhile, by the same approach we can deal with the general polyharmonic cases.

关键词： Bi-harmonic parabolic Lp estimates existence uniqueness.

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

2p^2阶3度Cayley图(英文)

数学进展 2006年第5期35卷 581-589页

作者：于汇霞周进鑫王玲丽北京交通大学理学院北京100044 山西师范大学数学系太原山西041004

Cayley图Cay(G,S)称之为正规的,如果G的右正则表示是Cay(G,S)全自同构群的正规子群。本文决定了2p^2(p为素数)阶群上3度连通Cayley图的正规性,作为该结果的一个应用,对每一个1(?)s(?)5,对2p^2阶3度s-正则Cayley图作了分类。

关键词： Cayley图正规Cayley图 s-正则图