决策信息系统中的拓扑学方法

在决策信息系统中引入拓扑结构,借助拓扑学的基本概念(拓扑、内部和闭包等)研究决策问题,用它们刻画决策信息系统中的一些重要概念(决策协调集、决策约简集、下近似协调集、下近似约简集、上近似协调集、上近似约简集),并利用它们把这些重要概念推广到最一般的情况,建立起相应的约简理论.     

甲基紫分光光度法测定痕量钒

在碱性条件下,甲基紫（ＭＶ）与钒（Ｖ）反应形成紫色缔合物,吸收峰位于５８０ｎｍ,缔合成组成摩尔比为Ｖ（Ｖ）：ＭＶ＝１：３,表观摩尔吸光系数ε５８０＝２．５＊１０＾７Ｌ／（ｍｏｌ．ｃｍ）的测定,结果令人满意。     

局部可分度量空间闭s映象的注记

该文讨论局部可分度量空间闭s映象的分解定理, 证明了正则的Fréchet空间是局部可分度量空间的闭s映象当且仅当满足如下条件: 具有点可数的cs*网, 第一可数的闭子空间是局部可分的, 且Lindelof的闭子空间是可分的.     

Chemiluminescence flow injection analysis of 1,3-dichloro-5,5-dimethylhydantoin in swimming pool water

A new chemiluminescence (CL) flow-injection method is proposed for the determination of 1,3-dichloro-5,5-dimethylhydantoin (DDH). The method is based on the chemiluminescent reaction of DDH and luminol-H(2)O(2) in an alkaline medium (pH 12.0-12.5). The concentration of the analyte shows a good linear relationship with the produced luminescence intensity in the range of 3.0x10(-8) to 8.0x10(-6) mol l(-1). The detection limit of the proposed method is 1.0x10(-8) mol l(-1) and the relative standard deviation (R.S.D.) is 4.7% (n=5) at 5.0x10(-7) mol l(-1). This method was successfully applied to the determination of trace amounts of this disinfectant in water samples obtained from five different swimming pools. Satisfying recovery values were also obtained.     

子种绿A与锡反应分光光度法测定痕量锡

探讨了在氨性介质中子种绿Ａ（Ｃ３７Ｈ３５Ｎ２Ｏ６Ｓ２Ｎａ） 染料与锡（ＩＶ） 反应形成离子缔合物的最佳条件,建立了测定痕量锡的新方法。子种绿Ａ—Ｓｎ（ＩＶ） 缔合物的最大吸收波长位于６３０ ｎｍ ,表观摩尔吸光系数ε６３０ ＝ １．７×１０６ Ｌ／（ｍｏｌ·ｃｍ）,锡浓度在０～８０ ｕｇ／Ｌ 范围内遵守比耳定律。用于水样与罐头食品分析,结果令人满意。     

Central Extensions and Derivations of the Lie Algebras of Skew Derivations for the Quantum Torus

ABSTRACT

In this article, we study the central extensions and derivations of the Lie algebra of skew derivations for the quantum torus. The results of the article generalize those obtained in Jiang and Meng (1998a Jiang , C. , Meng , D. ( 1998a ). The derivation algebra of the associative algebra C _q [X, Y, X ^?1, Y ^?1] . Comm. Algebra 26 : 1723 – 1736 . [CSA] [Taylor &; Francis Online], [Web of Science ®] , [Google Scholar] b Jiang , C. , Meng , D. ( 1998b ). The automorphism group of the derivation algebra of the Virasoro-like algebra . Adv. Math. (China) 27 : 175 – 183 . [CSA]  [Google Scholar]) and Kirkman et al. (1994 Kirkman , E. , Procesi , C. , Small , L. ( 1994 ). A q-analog for the Virasoro algebra . Comm. Algebra 22 : 3755 – 3774 . [CSA] [Taylor &; Francis Online], [Web of Science ®] , [Google Scholar]).     

关于紧覆盖分层强s-映射

本文给出了度量空间的紧覆盖分层强s-映象的一些新刻画.     

Generalized metric spaces with algebraic structures

We discuss generalized metrizable properties on paratopological groups and topological groups. It is proved in this paper that a first-countable paratopological group which is a β-space is developable; and we construct a Hausdorff, separable, non-metrizable paratopological group which is developable. We consider paratopological (topological) groups determined by a point-countable first-countable subspaces and give partial answers to Arhangel'skii's conjecture; Nogura-Shakhmatov-Tanaka's question (Nogura et al., 1993 [23]). We also give a negative answer to a question in Cao et al. (in press) [10]. Finally, remainders of topological groups and paratopological groups are discussed and Arhangel'skii's Theorem (Arhangel'skii, 2007 [3]) is improved.     

连通度量空间的映象

拓扑空间X称为s连通,若X不能表示为两个非空的不相交的序列开集之并.本文纠正了A.Fedeli 和A.Le Donne关于连通度量空间映象的错误论证,证明了s连通性可刻画为连通度量空间的连续的序列覆盖映象,从而导出连通的序列空间(或FrEchet空间)可刻画为连通度量空间的商映象(或伪开映象),回答了V.V.Tkachuk在Proc.Amer.Math Soc.上提出的问题.     

Notes on sequentially connected spaces

Summary We discuss the relationship between two different sequential connectedness, and prove that sequential connectedness is countably multiplicative.