The draft of coal mine excavation plan is typically an unhealthy structural and complex tech economic problem.
矿井采掘计划的编制是典型的不良结构和复杂的技术经济问题。
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However, the resource-bearing regions distribute uneven. The conditions of complexcoal mining technology and biological environments limit the coal resource development of energy bases.
This observation, as the first evidence, experimentally supports the theory of possible occurrence of iron-polysulfur complex in coal suggested recently.