• CHEN, HUANYIN (Department of Mathematics, Zhejiang Normal University) ;
  • CHEN, MIAOSEN (Department of Mathematics, Zhejiang Normal University)
  • Published : 2005.02.01


In this paper, we establish necessary and sufficient conditions for an exchange ideal to be a qb-ideal. It is shown that an exchange ideal I of a ring R is a qb-ideal if and only if when-ever $a{\simeq}b$ via I, there exists u ${\in} I_q^{-1}$ such that a = $ubu_q^{-1}$ and b = $u_q^{-1}$. This gives a generalization of the corresponding result of exchange QB-rings.


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