Water inrush from the bottom coal layer in mining work faced now is rather serious in Northern China coalfield, which constraints seriously the normal economical benefits.
英
美
释义
在我国华北煤矿区,回采工作面煤层底板突水问题相当严重,困扰着煤矿经济效益的正常发挥。
把海词放在桌面上,查词最方便
触屏版
|
电脑版
©2003 - 2024 海词词典(Dict.cn)
立即下载