Funding for this research was provided by:
Fundamental Research Funds for the Central Universities (2011YZ10)
National Natural Science Foundation of China, Excellent Young Scientists Fund (No. 51422404)
NSFC-Shanxi Joint Fund for Coal-Based Low-Carbon Technology (No. U1710258)
Article History
Received: 26 January 2018
Accepted: 16 June 2018
First Online: 3 July 2018
Compliance with ethical standards
:
: The authors declare no conflict of interest.