1. School of Public Health, University of South China, Hengyang 421001, P. R. China
2. Hunan Province Key Laboratory of Green Development Technology for Extremely Low Grade Uranium Resources, University of South China, Hengyang 421001, P. R. China
3. Institute of Pathogenic Biology, University of South China, Hengyang 421001, P. R. China
4. School of Chemistry and Chemical Engineering, University of South China, Hengyang 421001, P. R. China