If R is a right coherent ring, then left R-modules have covers by submodules of flat R-
modules if and only if all injective left R-modules have flat covers. This is the case if R is …

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 study the class of complexes of FP-injective left R-modules. It is shown that
the pair is a complete cotorsion pair. If R is a left coherent ring, it is proved that every …

We consider the perfect cotorsion pair (𝒫1, 𝒟) over a commutative ring (often over a domain)
R consisting of modules of projective dimension≤ 1 and of divisible modules, respectively …

A ring is called $ n $-perfect ($ n\geq 0$), if every flat module has projective dimension less
or equal than $ n $. In this paper, we show that the $ n $-perfectness relate, via homological …

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 …

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

Let R be a commutative Noetherian ring with non-zero identity, na non-negative integer, 𝔞
an ideal of R with dim (R/𝔞)≤ n+ 1, and X an arbitrary R-module. In this paper, we prove the …

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 …