1. Key Laboratory of Radiation Physics and Technology of the Ministry of Education, Institute of Nuclear Science and Technology, Sichuan University, Chengdu 610064, P. R. China
2. College of Chemistry, Key Laboratory of Radiation Physics and Technology of the Ministry of Education, Sichuan University, Chengdu 610064, P. R. China
3. Department of Nuclear Medicine, West China Hospital of Sichuan University, Chengdu, Sichuan 610041, P. R. China