1. School of Physics and Electronics, Qiannan Normal University for Nationalities, Duyun 558000, China
2. School of Geological Science and Survey Engineering, China University of Mining and Technology, Beijing 100083, China
3. Polymer Program, Institute of Materials Science, University of Connecticut, Storrs, Connecticut 06269, United States
4. School of Public Health, Nantong University, Nantong 226019, China
5. Department of Chemical and Biomolecular Engineering, University of Connecticut, Storrs, Connecticut 06269, United States