Affiliation: | 1. Department of Chemistry, Xiangtan University, Xiangtan 4111201 (China);2. Department of Chemistry, Tsinghua University, Beijing 100084 (China), Fax: (+86)?10‐62771149;3. Department of Chemistry and Chemical Engineering, Hunan University of Science and Technology, Xiangtan 4111201 (China);4. Department of Chemistry, Central China Normal University, Wuhan 430079 (China) |