1. Center for Advanced Materials Research & Faculty of Arts and Sciences, Beijing Normal University, Zhuhai 519087, P. R. China
2. Key Laboratory of Radiopharmaceuticals, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875, P. R. China
3. School of Medical Imaging, Xuzhou Medical University, Xuzhou, Jiangsu 221006, China
4. Department of Molecular & Cellular Physiology, School of Medicine, Stanford University, California 94305, United States
5. Instrumentation and Service Center for Science and Technology, Beijing Normal University, Zhuhai 519087, China