1. School of Chemistry and Chemical Engineering, Hunan University of Science and Technology, Xiangtan, P. R. China;
2. Hunan Provincial Key Laboratory of Controllable Preparation and Functional Application of Fine Polymers, Hunan University of Science and Technology, Xiangtan, P. R. China;
3. Department of Orthopedics, The Second Xiangya Hospital, Central South University, Changsha, P. R. China;
4. Key Laboratory of Theoretical Organic Chemistry and Function Molecule of Ministry of Education, Hunan University of Science and Technology, Xiangtan, P. R. China