1. State Key Lab of Polymer Physics and Chemistry; Changchun Institute of Applied Chemistry; Chinese Academy of Sciences; Changchun 130022 P. R. China
2. State Key Laboratory of Breeding Base of Green Pesticide and Agricultural Bioengineering; Center for R&D of Fine Chemicals; Guizhou University; Guiyang 550025 P. R. China
3. Department of Chemistry and Biochemistry; University of South Carolina; Columbia SC 29208 USA