A description is made of the four technical renovation programmes intended to be undertaken in the near future by Sanjiazi Coal Mine, Nanpiao Mining Administration for better the economic result.

 
  • 介绍了南票矿务局三家子煤矿为提高水力采煤的经济效益近期将进行的四项技术改造内容:(1)炮助水采;
今日热词
目录 附录 查词历史