In this paper some properties of the rings satisfying a special ascending chain condition for right annihilators, and some relations to left, ringt perfect rings and QF righs are discussed; As an application of Goldie theorem, a condition is given for a prime ideal is a completely prime ideal in this class of rings.

It is proved that a ring satisfying special ACC on right annihilators is QF if it is two-sided self-injective or it is a left IF ring.

Abstract This article explains the measure points of using parallel steel - wood truss through construction examples, and their economic benifits and advantage under special conditions.

The application of single-layer steel sheet pile cofferdams to especial conditions of the Laohekou hanjiang river bridge;