摘要
本文引入了FI-gr-内射模及强FI-gr-内射模的概念,并说明它们与分次内射模之间的相互关系。证明了分次环R是分次QF环当且仅当每个分次模是强FI-gr-内射模;设R为左分次凝聚环,则l.FP-gr-dim(R)≤1当且仅当每个FI-gr-内射模是分次内射模。此外,还证明了l.gr-fiD(R)=sup{gr-pd(L)|L为FP-gr-内射模}。
In this paper,the notions of FI-gr-injective modules and strongly FI-gr-injective modules are introduced,and the relationship between them and graded injective modules is explained.It is proved that the graded ring Ris a gr-QF ring if and only if each graded module is a strongly FI-gr-injective module;suppose Ris a left gr-coherent ring,then l.FP-gr-dim(R)≤1 if and only if each FI-gr-injective module is a graded injective module.In addition,it is also proved that l.gr-fiD(R)=sup{gr-pd(L)|Lis an FP-gr-injective module}.
引文
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