The purpose of this paper is to prove the following result: Let R be a 2-torsion free ring and T: R?R an additive mapping such that T is left (right) Jordan ?-centralizers on R. Then T is a left (right) ?-centralizer of R, if one of the following conditions hold (i) R is a semiprime ring has a commutator which is not a zero divisor . (ii) R is a non commutative prime ring . (iii) R is a commutative semiprime ring, where ? be surjective endomorphism of R . It is also proved that if T(x?y)=T(x)??(y)=?(x)?T(y) for all x, y ? R and ?-centralizers of R coincide under same condition and ?(Z(R)) = Z(R) .

In this paper, we prove that; Let M be a 2-torsion free semiprime  which satisfies the condition  for all  and α, β . Consider that  as an additive mapping such that  holds for all  and α , then T is a left and right centralizer.

In this paper, we will generalized some results related to centralizer concept on
prime and semiprime Γ-rings of characteristic different from 2 .These results
relating to some results concerning left centralizer on Γ-rings.

Let R be a semiprime ring with center Z(R) and U be a nonzero ideal of R. An additive mappings are called right centralizer if ( ) ( ) and ( ) ( ) holds for all . In the present paper, we introduce the concepts of generalized strong commutativity centralizers preserving and generalized strong cocommutativity preserving centralizers and we prove that R contains a nonzero central ideal if any one of the following conditions holds: (i) ( ) ( ), (ii) [ ( ) ( )] , (iii) [ ( ) ( )] [ ], (iv) ( ) ( ) , (v) ( ) ( ) , (vi) [ ( ) ( )] , (vii) ( ) ( ) ( ), (viii) ( ) ( ) for all .

     In this paper, we introduce the concept of generalized strong commutativity (Cocommutativity) preserving right centralizers on a subset of a Γ-ring. And we generalize some results of a classical ring to a gamma ring.

Let M be a weak Nobusawa -ring and γ be a non-zero element of Γ. In this paper, we introduce concept of k-reverse derivation, Jordan k-reverse derivation, generalized k-reverse derivation, and Jordan generalized k-reverse derivation of Γ-ring, and γ-homomorphism, anti-γ-homomorphism of M. Also, we give some commutattivity conditions on γ-prime Γ-ring and γ-semiprime Γ-ring .

The purpose of this paper is to prove the following result : Let R be a 2-torsion free prime *-ring , U a square closed *-Lie ideal, and let T: RR be an additive mapping. Suppose that 3T(xyx) = T(x) y*x* + x*T(y)x* + x*y*T(x) and x*T(xy+yx)x* = x*T(y)x*2 + x*2T(y)x* holds for all pairs x, y  U , and T(u) U, for all uU, then T is a reverse *-centralizer.

Nilpotency of Centralizers in Prime Rings

In this paper, we study the concepts of generalized reverse derivation, Jordan
generalized reverse derivation and Jordan generalized triple reverse derivation on -
ring M. The aim of this paper is to prove that every Jordan generalized reverse
derivation of -ring M is generalized reverse derivation of M.

n this paper , we prove that if T is a 2-torsion free triangular ring and be a family of additive mapping then satisfying is a higher centralizer which is means that is Jordan higher centralizer on 2-torsion free triangular ring if and only if is a higher centralizer and also we prove that if be a family of additive mapping satisfying the relation Σ , Then is a higher centralizer.