Funding for this research was provided by:
National Natural Science Foundation of China (61379089)
Natural Science Foundation of the Department of Education of Sichuan Province (16ZA0060)
National Natural Science Foundation of China (41604114)
Innovation and Entrepreneurship Foundation of Southwest Petroleum University (SWPUSC16-003)
Article History
Received: 21 October 2016
Accepted: 26 February 2018
First Online: 3 March 2018