1. School of Environment, Northeast Normal University, Changchun 130117, China
2. Department of Chemical and Environmental Engineering, Yale University, New Haven, Connecticut 06520-8286, United States
3. State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China
4. School of Municipal and Environmental Engineering, Jilin Jianzhu University, Changchun 130118, China