1. State
Key Laboratory of Rare Earth Resource Utilization, Changchun Institute
of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, P. R. China
2. College
of Chemical and Environmental Engineering, Shandong University of Science and Technology, Qingdao 266590, P. R. China
3. Graduate School of the Chinese Academy of Sciences, Beijing 100049, P. R. China