In this paper we show that if R is a ring of Krull dimension d and M is a strongly copure flat
(respectively, strongly copure injective) module, then E⊗ RM (respectively, HomR (E, M)) is …

Several authors have been interested in cotorsion theories. Among these theories we figure
the pairs $(\mathcal P_n,\mathcal P_n^{\perp}) $, where $\mathcal P_n $ designates the set …

We study the existence of some covers and envelopes in the chain complex category of R-
modules. Let (𝒜, ℬ) be a cotorsion pair in R-Mod and let ℰ𝒜 stand for the class of all exact …

In this paper, we study completeness of cotorsion pairs in the category of complexes of R-
modules. Let (A, B) be a cotorsion pair in R-Mod. It is shown that the cotorsion pair …

Let R be a ring (not necessarily commutative). A left R-module is said to be cotorsion if Ext 1
R (G, M)= 0 for any flat R-module G. It is well known that each pure-injective left R-module is …

In this paper, we introduce the concept of n-IFP-flat (respectively, n-IFP-injective) modules as
nontrivial generalization of flat (respectively, injective) modules. We first investigate various …

We prove that, if GProj is the class of all Gorenstein projective modules over a ring R, then
GP=(GProj, GProj⊥) is a cotorsion pair. Moreover, GP is complete when all projective …

Let dwI denote the class of#-injective complexes of left R-modules (ie, complexes of injective
left R-modules). We prove that over left noetherian rings R, the pair (⊥(dwI), dwI) is a perfect …

Let R be a right perfect ring, and let (ℱ, 𝒞) be a cotorsion theory in the category of right R-
modules ℳ R. In this article, it is shown that every right R-module has a superfluous ℱ-cover …