Funding for this research was provided by:
the National Natural Science Foundation of China (No. 61701284)
the China Postdoctoral Science Foundation (No.2016M602165)
the Innovative Research Foundation of Qingdao (No.19-6-2-1-cg)
the Opening Project Fund of State Key Laboratory of Mining Disaster Prevention and Control Cofounded by Shandong Province and the Ministry of Science and Technology (No. MDPC201715)
the Key Research and Development project of Shandong Province (No. 2018GHY115022)
the Shandong Natural Science Foundation (No. ZR2017MF070)
the Qingdao Postdoctoral Application Research Project (No. 2016113)
the Science and Technology Support Plan of Youth Innovation Team of Shandong higher School (No. 2019KJN024)
Article History
Received: 30 May 2020
Accepted: 1 October 2020
First Online: 16 October 2020
Competing interests
: The authors declare that they have no competing interests.