Production and practice of coal mine proves that firedamp extraction and gush has the characteristic of subarea and zonation.

 
  • 煤礦的生產(chǎn)和實(shí)踐證明,礦井瓦斯的抽放及礦井瓦斯的涌出具有分區和成帶的特點(diǎn)。
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