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。

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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。

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

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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.

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