1. Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province, State Key Laboratory of Applied Organic Chemistry and Key Laboratory of Special Function Materials and Structure Design (MOE), College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou730000, P. R. China
2. Department of Radiology, Xinqiao Hospital, Army Medical University, Chongqing400037, P. R. China
3. Department of Radiology, Second Affiliated Hospital of Chongqing Medical University, No. 74 Linjiang Rd, Yuzhong District, Chongqing400010, P.R. China