山西省煤基重点科技攻关项目FT-2014-01-15;山西省青年科学基金2015021159;山西省重点研发计划项目201603 D321008资助 [Supported by the Key Scientific Development Project of Shanxi Province, ChinaFT-2014-01-15;the Natural Science Foundation of Shanxi Province, China2015021159;the Social Development Foundation of Shanxi 201603D321008]