1. Jiangsu Key Laboratory of Industrial Water-Conservation & Emission Reduction, College of Environment, Nanjing Tech University; Nanjing 211800 China
2. Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, State Ministry of Education, Urban Construction and Environmental Engineering, Chongqing University; Chongqing 400045 China
3. College of Civil Engineering, Hunan University of Science & Technology; Xiangtan Hunan 411201 China