1. College of Environment and Ecology, Chongqing University, Chongqing 400045, P. R. China
2. Environment Monitoring Center of Jiangsu Province, Nanjing 210036, P. R. China
3. School of Chemistry and Chemical Engineering, Chongqing University, Chongqing 401331, P. R. China
4. Key Laboratory of the Three Gorges Reservoir Region’s Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, P. R. China
5. Department of Civil and Environmental Engineering, Colorado School of Mines, 1500 Illinois Street, Golden, Colorado 80401, United States