摘要
引进了Ｓ－系的τ－纯同余的概念并利用它刻画Ｓ－系的扭类与扭自由类。
In the paper,we introduce τ-pure congruences and τ-torsin radical congreences.We prove that the class Fτ of S-systems is torsion free if and only if for any m∈M,m ⊥ is τ- pure for each M∈F,and give some characteries of torsion theories.
出处
《南昌大学学报（理科版）》
CAS
1999年第1期5-8,共4页
Journal of Nanchang University(Natural Science)
关键词
扭论
扭自由类
纯同余
扭根同余
S系
模范畴
torsion theory,torsionfree class,pure congruence,torsionradical congruence
