1. School of Chemistry and Chemical Engineering and Shanghai Key Laboratory of Electrical Insulation and Thermal Aging, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, P. R. China
2. Key Laboratory for Organism Resources of the Changbai Mountain and Functional Molecules, Ministry of Education, and Department of Chemistry, College of Science, Yanbian University, 977 Gongyuan Road, Yanji, Jilin 133002, P. R. China