Affiliation: | 1. Key Laboratory of Medicinal Chemistry and Molecular Diagnosis, Ministry of Education, College of Chemistry and Environmental Science, Hebei University, Baoding, 071002 (P. R. China), Fax: (+86)?312‐5079317;2. State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (P. R. China), Fax: (+86)?431‐85685653 |