Funding for this research was provided by:
the National Natural Science Foundation of China (21962001, 21862001)
Ningxia Scientific and Technological Innovation Leading Personnel Training (KJT2017006)
The talent highland of research and development of high-value utilization technology of low-quality resources in Ningxia, China
Clean Energy Institute (ZDZX201803)
Article History
Received: 16 October 2019
Accepted: 14 February 2020
First Online: 21 February 2020
Compliance with ethical standards
:
: The authors declare that they have no conflict of interest.