Funding for this research was provided by:
National Natural Science Foundation of China (51874300)
National Natural Science Foundation of China and Shanxi Provincial People's Government Jointly Funded Project of China for Coal Base and Low Carbon (U1510115)
Article History
Received: 29 February 2020
Accepted: 3 June 2020
First Online: 23 June 2020
Consent for publication
: We agree to the publication of the paper.
: The authors declare that they have no competing interests.