Syntheses,Crystal Structure and Luminescent Properties of Co-ordination Networks Based on Copper(I) Iodide Clusters from 1, 4-Bis(imidazole-1-ylmethyl)benzene

This paper presents novel and distinctive Copper(I) iodide polymers with intriguing structure motifs, constructed from 1, 4-bis(imidazole-1-ylmethyl)benzene (bix). Treatment of bix with CuI generated [(Cu₄I₄)(bix)₂] _n 1, whose X-ray single crystal structural determination revealed a novel 2-D battlement-like sheet structure with square grids based on distorted cubane-like Cu₄I₄ clusters. The structural features and photoluminescence of the complexes are discussed. The present finding may provide insight into the coordination versatility of copper(I) halide clusters with N-donor ligands and an inspiration for the self-assembly of novel supramolecular networks based on copper(I) halide clusters.     

L-模糊弱理想与L-模糊近理想

给出了L-模糊弱理想与L-模糊近理想的概念并借助于L-模糊集的几种截集给出了它们的刻画,研究了它们的运算性质。     

L-fuzzy商群的L-fuzzy同构定理

给出了L-fuzzy群的L-fuzzy同态基本定理。同时建立了L-fuzzy商群的L-fuzzy同态和L-fuzzy同构定理。     

无穷维L1空间至连续函数空间的等距逼近问题

证明了无穷维Ｌ~１空间至连续函数空间的等距逼近问题的回答是否定的．     

L－fuzzy集网的R－收敛性质

本文在ＬＦ拓扑空间中建立了Ｌ－ｆｕｚｚｙ集网的弱收敛（Ｒ－收敛）概念，应用文［４］中的Ｒ－闭包，系统讨论了它们的性质，证明了等式ＲｌｉｍＡ＿ｎ＝∧（∨Ａ＿ｍ）＿Ｒ和ＲｌｉｍＡ＿ｎ＝Ａ＿ｎ＝∧（∨Ａ＿ｍ）＿Ｒ并且给出了Ｌ－ｆｕｚｚｙ集网与其子网之间的关系。     

Extensional flow —a mathematical perspective

Extensional flow has been studied extensively for less than half the lifetime of the word rheology, although measurement of viscosity from extensional flow experiments can be traced back to the beginning of this century. In recent years extensional flow has, however, attracted a great deal of attention in conferences, workshops and special issues of journals. This has coincided with interest, both scientific and industrial, in elasticoviscous fluids, notably polymer solutions and molten polymers. The particular success of specialized, carefully targetted or focussed, workshops is highlighted.A personal reflection is offered here on some of the issues in extensional flow from the point of view of an applied mathematician. The state of the art, as far as extensional viscosity is concerned, is briefly surveyed. Both theoretical and practical aspects of the task of obtaining useful extensional flow properties are outlined, drawing heavily on a recent review by James and Walters. Particular attention is paid to spinning experiments, drawing heavily on recent theoretical investigations by the author. The merits of defining a spinning viscosity, in addition to the formally defined tensile viscosity, are advanced. The idea of general approximations for extensional flows is reviewed and some aspects of this are highlighted, particularly in connection with Metzner's idea of extensional primary field (EPF) approximations. Finally qualitative investigations of the behaviour of model fluids (in model flows) are illustrated and a new result on the boundedness of solutions for unsteady uniaxial extension of a FENS-P dumbbell model is presented.Presented as a keynote lecture at the 4the European Rheology Conference, September 4–9, 1994, Seville, Spain     

L─fts中的导集和导算子

本文首先讨论了Ｌ─ｆｔｓ中ＬＦ集的聚点的分布；其次讨论了ＬＦ集的导集的一些性质，并给出了一般的Ｌ─ｆｔｓ中类似于杨忠道定理的结果；本文最后引进了导算子的概念，并用其刻划一般的Ｌ─ｆｔｓ．     

Topological and analytical properties of Sobolev bundles,I: The critical case

We study the interrelationship between topological and analytical properties of Sobolev bundles and describe some of their applications to variational problems on principal bundles. We in particular show that the category of Sobolev principal G-bundles of class W ^2,m/2 defined over M ^m is equivalent to the category of smooth principal G-bundles on M and give a characterization of the weak sequential closure of smooth principal G-bundles with prescribed isomorphism class. We also prove a topological compactness result for minimizing sequences of a conformally invariant Yang-Mills functional.      

Uniformity Structures on L-Fuzzy Spaces

We extend the notion of a uniform space in a natural way by defining a uniform spaces in L-fuzzy spaces.Although these spaces seem quite similar to ordinary case,we show that the category of this uniform spaces is a good extension of the category of ordinary uniform spaces and the category of L-uniform spaces.Moreover,we introduce the concept of uniform topological spaces in the framework of uniform spaces in L-fuzzy spaces.Furthermore,the relation between proximity and uniform spaces in L-fuzzy spaces will...     

Bounded-hops power assignment in ad hoc wireless networks

Motivated by topology control in ad hoc wireless networks, Power Assignment is a family of problems, each defined by a certain connectivity constraint (such as strong connectivity). The input consists of a directed complete weighted digraph G=(V,c) (that is, ). The power of a vertex u in a directed spanning subgraph H is given by , and corresponds to the energy consumption required for node u to transmit to all nodes v with uv∈E(H). The power of H is given by . Power Assignment seeks to minimize p(H) while H satisfies the given connectivity constraint.Min-Power Bounded-Hops Broadcast is a power assignment problem which has as additional input a positive integer d and a r∈V. The output H must be a r-rooted outgoing arborescence of depth at most d. We give an (O(logn),O(logn)) bicriteria approximation algorithm for Min-Power Bounded-Hops Broadcast: that is, our output has depth at most O(dlogn) and power at most O(logn) times the optimum solution.For the Euclidean case, when c(u,v)=c(v,u)=∥u,v∥^κ (here ∥u,v∥ is the Euclidean distance and κ is a constant between 2 and 5), the output of our algorithm can be modified to give a O((logn)^κ) approximation ratio. Previous results for Min-Power Bounded-Hops Broadcast are only exact algorithms based on dynamic programming for the case when the nodes lie on the line and c(u,v)=c(v,u)=∥u,v∥^κ.Our bicriteria results extend to Min-Power Bounded-Hops Strong Connectivity, where H must have a path of at most d edges in between any two nodes. Previous work for Min-Power Bounded-Hops Strong Connectivity consists only of constant or better approximation for special cases of the Euclidean case.