1. State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, 222 South Tianshui Road, Lanzhou 730000, P. R. China
2. First Hospital of Lanzhou University, Lanzhou University, 222 South Tianshui Road, Lanzhou 730000, P. R. China
3. College of Chemistry and Chemical Engineering, Northwest Normal University, 967 East Anning Road, Lanzhou 730070, P. R. China