1. School of Materials and Chemical Engineering University Bengbu 1866 Caoshan Road Anhui 233030 P. R. China
2. Department of Chemistry University of Science and Technology of China 96 Jinzhai Road Hefei Anhui 230026 P. R. China
3. Bengbu Product Quality and Inspection Institute 100 Anmin Road Bengbu Anhui 233030 P. R. China