1. State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, School of Chemistry & Chemical Engineering, Nanjing University, Nanjing 210093, P. R. China
2. Physics Department and Shanghai
Key Laboratory of Magnetic Resonance, East China Normal University, Shanghai 200062, P. R. China
3. College of Material Science and
Engineering, Polymer Institute, South China University of Technology, Guangzhou, Guangdong 510640, P. R. China