Let R be a noncommutative ring. The zero-divisor graph of R, denoted by Γ(R), is the (directed) graph with vertices Z(R)∗ = Z(R)− {0}, the set of nonzero zero-divisors of R, and for distinct x, y ∈ Z(R)∗, there is an edge x → y if and only if xy = 0. In this paper we investigate the zero-divisor graph of triangular matrix rings over commutative rings. Mathematics Subject Classification: 16S70; ...

A $\ast$-ring
 $R$ is called a $\pi$-Baer $\ast$-ring, if for any projection invariant left ideal $Y$ of $R$, the right annihilator $Y $
 generated, as ideal, by projection.
 In this note, we
 study some properties such $\ast$-rings.
 We indicate interrelationships between $\ast$-rings and related classes rings as
 rings, Baer $\ast$-rings, quasi-Baer $\ast$-rings....

we show  that a projective maximal submodule of afinitely generated, regular, extending module is a directsummand. hence, every finitely generated, regular, extendingmodule with projective maximal submodules is semisimple. as aconsequence, we observe that every regular, hereditary, extendingmodule is semisimple. this generalizes and simplifies a result of  dung and   smith. as another consequen...

Matrix-rings play a fundamental role in mathematics and its applications. A difficult question is to decide whether a given ring is isomorphic to a matrixring or one of its variants. Several “hidden matrix-rings” have been shown in the literature (see [5]). These rings did not appear as being matrix-rings at the first sight, nevertheless they proved out to be isomorphic to matrix-rings. Another...

The classical Morita Theorem for rings established the equivalence of three statements, involving categorical equivalences, isomorphisms between corners finite matrix rings, and bimodule homomorphisms. A fourth equivalent statement (established later) involves an isomorphism infinite rings. In our main result, we establish analogous statements graded homomorphisms,