S-SUPERFLUOUS AND S-ESSENTIAL HOMOMORPHISMS  

作　　者：朱海燕 丁南庆 

机构地区：[1]Department of Mathematics,Zhejiang University of Technology [2]Department of Mathematics,Nanjing University

出　　处：《Acta Mathematica Scientia》2009年第2期391-401,共11页数学物理学报（B辑英文版）

基　　金：Supported by Specialized Research Fund for the Doctoral Program of Higher Education (20050284015);National Natural Science Foundation of China (10771096)

摘　　要：Let R be a ring and S a class of R-modules. S-superfluous epimorphisms and S-essential monomorphisms are introduced and studied in this article. As applications, some new characterizations of von Neumann regular rings and perfect rings are given. Finally, these notions are also used to study minimal homomorphisms.Let R be a ring and S a class of R-modules. S-superfluous epimorphisms and S-essential monomorphisms are introduced and studied in this article. As applications, some new characterizations of von Neumann regular rings and perfect rings are given. Finally, these notions are also used to study minimal homomorphisms.

关 键 词：S-essential MONOMORPHISM S-superfluous EPIMORPHISM （pre）cover （pre）envelope 

分 类 号：O153.3[理学—数学] O153.2[理学—基础数学]