1. State Key Laboratory of Geohazard Prevention and Geoenvironment Protection College of Materials, Chemistry & Chemical EngineeringChengdu University of Technology Chengdu 610059 P. R. China
2. Department of Chemistry Graduate School of ScienceTohoku University 6-3 Azaaoba Aramaki, Aoba-ku Sendai 980-8578 Japan
3. College of Environment and EcologyChengdu University of Technology Chengdu 610059 P. R. China