1. School of Nuclear Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, P. R. China
2. Guangxi Key Laboratory of Processing for Non-ferrous Metallic and Featured Materials, Guangxi University, Nanning 530004, P. R. China
3. College of Resources, Environment and Materials, Guangxi University, Nanning 530004, P. R. China
4. Shanghai Institute of Measurement and Testing Technology, Shanghai 201203, P. R. China