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991.
WANG Jian & DU Beiliang Nantong Vocational College Nantong China Department of Mathematics Suzhou University Suzhou China 《中国科学A辑(英文版)》2006,(7)
LetλKm,n be a bipartite multigraph with two partite sets having m and n vertices, respectively. A Pν-factorization ofλKm,n is a set of edge-disjoint Pν-factors ofλKm,n which partition the set of edges ofλKm,n. Whenνis an even number, Ushio, Wang and the second author of the paper gave a necessary and sufficient condition for the existence of a Pν-factorization ofλKm,n. When v is an odd number, we proposed a conjecture. However, up to now we only know that the conjecture is true forν= 3. In this paper we will show that the conjecture is true whenν= 4k-1. That is, we shall prove that a necessary and sufficient condition for the existence of a P4k-1-factorization ofλKm,n is (1) (2k-1)m≤2kn, (2) (2k-1)n≤2km, (3)m n = 0 (mod 4k-1), (4)λ(4k-1)mn/[2(2k-1)(m n)] is an integer. 相似文献
992.
李文明 《数学物理学报(A辑)》2006,(Z1)
The author derives a kind of weighted norm inequalities which relate the multilinear potential type integral operators to the corresponding maximal operators. 相似文献
993.
谷峰 《数学物理学报(A辑)》2006,(Z1)
The purpose of this article is to study the weak and strong convergence of implicit iteration process with errors to a common fixed point for a finite family of asymptotically nonexpansive mappings and nonexpansive mappings in Banach spaces. The results presented in this article extend and improve the corresponding results of [1, 2, 4-9, 11-15]. 相似文献
994.
995.
D(β)-vertex-distinguishing total coloring of graphs 总被引:2,自引:0,他引:2
ZHANG Zhongfu LI Jingwen CHEN Xiang''''en YAO Bing WANG Wenjie & QIU Pengxiang Institute of Applied Mathematic Lanzhou Jiaotong University Lanzhou China College of Mathematics Information Science Northwest Normal University Lanzhou China College of Information Electrical Engineering Lanzhou Jiaotong University Lanzhou China 《中国科学A辑(英文版)》2006,(10)
A new concept of the D(β)-vertex-distinguishing total coloring of graphs, i.e., the proper total coloring such that any two vertices whose distance is not larger thanβhave different color sets, where the color set of a vertex is the set composed of all colors of the vertex and the edges incident to it, is proposed in this paper. The D(2)-vertex-distinguishing total colorings of some special graphs are discussed, meanwhile, a conjecture and an open problem are presented. 相似文献
996.
Banach空间中的X_d框架与Reisz基 总被引:1,自引:0,他引:1
本文引入并研究了Banach空间中的X_d框架,X_d Bessel列,紧X_d框架,独立X_d框架和X_d Riesz基等概念,给出了X_d框架和独立X_d框架的算子等价刻画,Banach空间X中存在X_d框架或X_d Riesz基的充要条件以及X_d框架的对偶框架存在的充要条件,讨论了Banach空间的基和X_d框架,X_d Riesz基之间的关系. 相似文献
997.
A novel conjugated polymer containing azobenzene and oxadiazole units was synthesized through multi-step synthesis.The structures and properties of monomer and polymer were characterized and evaluated with IR,1H NMR,UV,TGA and GPC,respectively.Polymer with long side chain of alkoxy shows good solubility,thermal stability and photoisomerization property. 相似文献
998.
A new sesquiterpene, named vladimenal (1), was isolated from the roots of Vladimiria souliei. The structure was elucidated on the basis of spectroscopic analysis. 相似文献
999.
GE HanQing LENG Yan ZHANG FuMin PIAO JiaRui ZHOU ChangJiang & WANG Jun State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemistry Chemical Engineering Nanjing University of Technology Nanjing China Petrochemical Research Institute PetroChina Company Ltd. Beijing 《中国科学B辑(英文版)》2009,(8)
Pyridine(Py)-modified Keggin-type vanadium-substituted heteropoly acids(PynPMo10V2O40,n=1 to 5) were prepared by a precipitation method as organic/inorganic hybrid catalysts for direct hydroxylation of benzene to phenol in a pressured batch reactor and their structures were detected by FT-IR.Among various catalysts,Py3PMo10V2O40 exhibits the highest catalytic activity(yield of phenol,11.5%),without observing the formation of catechol,hydroquinone and benzoquinone in the reaction with 80 vol% aqueous acetic ... 相似文献
1000.
Li Qiu Wang Qing Shan Li Hui Peng Ma Xiao Feng Guo Rui Hong Wang Gang Yao 《中国化学快报》2009,20(4):483-486
Polypropylene synthetic paper releasing anion was prepared from polypropylene resin,anion additives,titanium dioxide,etc.,by calendar forming method.The synthetic paper was tested by anion detector,SEM,AFM,etc.Tensile strength,elongation at break, right angle tear strength of the polypropylene synthetic paper reached the GB 13022 or QB/T1130 Standard.The synthetic paper was water and oil resistance,and released anions 10,530 cm~(-3).It was environment-friendly,and a kind of good material for human's heal... 相似文献