1. Key
Laboratory of Coal Methane and Fire Control, Ministry of Education, China University of Mining and Technology, Xuzhou, Jiangsu 221116, China
2. National
Engineering Research Center for Coal Gas Control, China University of Mining and Technology, Xuzhou, Jiangsu 221116, China
3. School of Civil, Mining & Environmental Engineering, University of Wollongong, Wollongong, New South Wales 2522, Australia