zone purification是什么意思

用法例句

The purities of tin(3 N,4 N,5 N)and tin bars purified by zone purification have been measured by the residual resistivity ratio(RRR)method.

采用剩余电阻率比（ＲＲＲ）方法对３Ｎ，４Ｎ，５Ｎ纯度的Ｓｎ和区域提纯Ｓｎ棒的纯度进行了测量。