Funding for this research was provided by:
National Natural Science Foundation of China (51374092, 51774111)
Joint Fund of Coal (U1261206)
Innovation and Outstanding Talent Project of Henan Province Science and Technology (184200510003)
Article History
Received: 29 August 2018
Accepted: 5 January 2019
First Online: 24 January 2019
Compliance with ethical standards
:
: The authors declare no conflict of interest.