Let R be a ring. A left R-module M is said to be min-injective if for any simple left ideal I. A
right R-module N is called min-flat if for any simple left ideal I. R is said to be a left min …

In this article, we characterize some rings in terms of the DG-projective, injective and flat
complexes. We also give some connections between DG-injective complexes and DG-flat …

In this article we consider only associative rings with nonzero identity and unitary modules. A
ring R is called a two-sided PF-ring or a ring with perfect duality if it is a left and right PF-ring …

Let R be a ring. For two fixed positive integers m and n, a right R-module M is called (m, n)-
injective in case every right R-homomorphism from an n-generated submodule of Rm to M …

THE EXISTENCE OF FLAT COVERS flat, then <j> is called a flat cover of M if F' F —^— MF (b)
¡ \ F —^ M Page 1 proceedings OF THE AMERICAN MATHEMATICAL SOCIETY Volume 122 …

A complex C of R-modules is called#-injective if all terms Ci are injective R-modules for i∈
ℤ. In this paper, we first give some characterizations and properties of#-injective complexes …

Let R be a ring. A right R− module M is called quasi-principally injective if it is M− principally
inj ective. In this paper, we give some characterizations and properties of principally inj …

Let R be a ring. A left R-module M (respectively right R-module N) is called FI-injective
(respectively FI-flat) if Ext1 (G, M)= 0 (respectively Tor1 (N, G)= 0) for any FP-injective left R …

In this paper, we introduce the notion of Gorenstein n-flat modules and Gorenstein n-
absolutely pure modules. First, we prove that the direct limit of Gorenstein n-flat modules …

We prove that (a) if R is left coherent, then a finitely presented right R–module M is copure
flat if and only if M is a cokernel of a flat preen-velope (b) if R is a ring and na nonnegative …