1. Qian Xuesen Laboratory of Space Technology China Academy of Space Technology 104 Youyi Road Beijing 100094 P. R. China
2. School of Environmental Science and Engineering Nanjing University of Information Science & Technology 219 Ningliu Road Nanjing 210044 P. R. China
3. College of Environmental Science and Engineering Taiyuan University of Technology Taiyuan 030024 P. R. China
4. Centre for Technology in Water and Wastewater (CTWW), School of Civil and Environmental Engineering University of Technology Sydney (UTS) Ultimo NSW 2007 Australia