This paper was supported by the National Natural Science Foundation of China (Nos. 61871210 and 61102108), Scientific Research Fund of Hunan Provincial Education Department (Nos. 16B225 and YB2013B039), the Natural Science Foundation of Hunan Province (No. 2016JJ3106), Chuanshan Talent Project of the University of South China, the Construct Program of Key Disciplines in USC (No. NHXK04), and Scientific Research Fund of Hengyang Science and Technology Bureau (No. 2015KG51).