On dense left ideal pure $S$-acts

Authors
Semnan University
Abstract
In this paper, similar to the Lembek's idea concerning a generalization of the notion of purity associated with a radical in the category of R-modules, we give the notion of purity related to a Hoehnke radical, d.l.i.pure, in the category of $S$-acts and investigate this notion. We also show that absolutely d.l.i.pure $S$-acts are exactly the $r$-weakly injective $S$-acts, for every Hoehnke radical $r$, and we give several characterization of d.l.ipure $S$-acts. We then present a closure operator induced by an $r$-dense left ideal which is closely related to the notion of d.l.i.purity and give a characterization of d.l.i.pure $S$-acts by this closure operator.

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Keywords

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