Practical experiences with shrinkage mining method for pillar extraction over the pust ten years were summarized.

 
  • 從我礦資源和礦柱回采實(shí)際情況出發(fā),總結了近十幾年來(lái)用留礦法回采底柱的實(shí)踐經(jīng)驗。
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目錄 附錄 查詞歷史
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