Funding for this research was provided by:
National Natural Science Foundation of China (71571023)
Fundamental Research Funds for the Central Universities (2018CDXYJX0019)
Graduate Research and Innovation Foundation of Chongqing (CYB19010)
Youth Foundation of Ministry of Education of China (19YJC630141)
Scientific and Technological Research Program of Chongqing Municipal Education Commission (KJQN201800832)
Article History
Received: 5 June 2019
Accepted: 17 February 2020
First Online: 24 February 2020