According to test chemical composition,macrofractography and observation of microstructure to a failure workpiece,the results show that there are much Widmanstatten structure and more MnS inclusions in the failure workpiece,and lead to failure of swing in the rolling direction.

According to test chemical composition, macrofractography and observation of microstructure of failure piston,finding some important questions in the workpiece.

According to test chemical composition,macrofractography and observation of microstructure to a failure workpiece,the results show that there are much Widmanstatten structure and more MnS inclusions in the failure workpiece,and lead to failure of swing in the rolling direction.

This paper try to use new thinking to mine electric circuit analysis way,probe into the use of circuit law,bring forward a new system of electric circuit analysis,here electric circuit analysis method is divided into four important trench : namely to be named as directness,equivalent,system & framework and macroscopical analysis.

This article makes a primary macro-analysis about the scope and categories of higher education in Western,Central,and Eastern areas,which help to generalize the overall view about the development of Chinese higher education and the further reorganization about the different kinds of higher education developments within the general pla.