Jia, Ling-Yun
Bai, Jing-Yue
Sun, Kun
Wang, Rong-fang
Feng, Han-Qing
Funding for this research was provided by:
National Natural Science Foundation of China (31560070, 31260059)
Key Project of Science and Technology Research of Chinese Ministry of Education (211190)
Fundamental Research Funds for the Gansu Universities of Gansu Provincial Department of Finance, the University Scientiic Research Project of Gansu Province (2015A-007)
Youth Teacher Scientiic Research Ability Promotion Plan Innovation Team Project of Northwest Normal University
Article History
Received: 29 June 2018
Accepted: 10 September 2018
First Online: 24 September 2018
Compliance with ethical standards
:
: The authors declare that they have no conflicts of interest.