Introduces the roadway gas drained technology for high gas mining face, it has resolved the gas control problems during primary mining face.

介绍了高瓦斯采煤工作面采用高抽巷抽放、尾抽巷抽放等专用巷道瓦斯抽放技术，解决了工作面初采期间的瓦斯问题。

youdao

Along with mining depth becoming deep and coal output increasing, the gas discharge increased, and gas problem of primary mining in coal face becomes important.

随着采煤深度的下延和产量的加大，瓦斯涌出量逐步增加，采煤工作面初采期间的瓦斯问题越来越引起重视。

youdao

Parallel rails had long been used in mining operations to move bigger loads, but horses were still the primary source of power.

在采矿作业中，平行铁轨早已被用来运送大件的货物，但马匹仍然是主要的运输工具。

youdao

Gemfields primary business is the mining, distribution and marketing of emeralds from the Kagem mine in Zambia.

FORBES: Mila Kunis Named Ambassador Of Emerald Company

The trojan is able to carry out many tasks, he added, but taking over computers for Bitcoin mining appears to be its primary function.

BBC: Skype trojan forces Bitcoin mining, security firm warns

Mine supply for silver is rising faster than for other metals, helped by an increase of by-product from gold-mining operations plus a number of major primary projects in recent years.

FORBES: Thomson Reuters GFMS' Newman: Silver May Move Toward $50 Yet In 2011