We prove that if a right distributive ring R, which has at least one completely prime ideal contained in the Jacobson radical, satisfies either a.c.c or d.c.c. on principal right annihilators, then the prime radical of R is the right singular ideal of R and is completely prime and nilpotent. These results generalize a theorem by Posner for right chain rings.

It is shown that the right-adequate duo ring with a nonzero Jacobson radical has stable range one. established class of complete matrices order 2 over elementary divisors Some classes unit-regular and clean are investigated.

Looking at the automata defined over a group alphabet as a nearring, we see that they are a highly complicated structure. As with ring theory, one method to deal with complexity is to look at semisimplicity modulo radical structures. We find some bounds on the Jacobson 2-radical and show that in certain groups, this radical can be explicitly found and the semisimple image determined.

The notions of a right quasiregular element and right modular right ideal in a near-ring are initiated. Based on these J 0(R), the right Jacobson radical of type-0 of a near-ring R is introduced. It is obtained that J 0 is a radical map andN(R)⊆ J 0(R), whereN(R) is the nil radical of a near-ring R. Some characterizations of J 0(R) are given and its relation with some of the radicals is also di...