Funding for this research was provided by:
National Natural Science Foundation of China (11604121)
Scientific Research Fund of Hunan Provincial Education Department (16B210)
Natural Science Fund Project of Hunan Province (2017JJ3255)
Natural Science Fund Project of Jishou University (jdx17036)
Article History
Received: 1 February 2018
Accepted: 6 April 2018
First Online: 14 April 2018