This paper analyzes the distribution characteristics of geomagnetic low-value displacement in Gansu and its adjacent areas from 1995 to 2003 on the basis of the
Based on the analyses of electromagnetic pressure on melt and heat induced in melt, the ratio of heat to pressure Q 0/ p m was defined. It was given th
The middle convex and varying ellipse piston is th e key component of an internal combustion engine In general,the piston is mac hined by non circular sect