1. State Key Laboratory of High Performance Ceramics and Superfine Microstructures; Shanghai Institute of Ceramics; Chinese Academy of Sciences; Shanghai 200050 P. R. China
2. Jiangsu Collaborative Innovation Center for Advanced Inorganic Functional Composites; Nanjing Tech University; Nanjing 210009 P. R. China
3. Institute of Radiation Medicine; Fudan University; Shanghai 200032 P. R. China
4. Department of Radiation Oncology; Shanghai Huadong Hospital; Fudan University; Shanghai 200040 P. R. China
5. Department of Radiology; Shanghai Cancer Hospital; Fudan University; Shanghai 200032 P. R. China