Funding for this research was provided by:
National Natural Science Foundation of China (51507013)
China Postdoctoral Science Foundation (2017M613034)
Natural Science Foundation of Shaanxi Province (2016JQ5012)
Science and Technology Research Project of Shaanxi Province (2016GY-043)
Postdoctoral Science Foundation of Shaanxi Province (2017BSHEDZZ36)
Article History
Received: 11 December 2017
Revised: 15 January 2018
Accepted: 17 January 2018
First Online: 16 February 2018