1. College of Chemistry; Sichuan University; Chengdu 610064 P. R. China
2. Key Laboratory of Magnetic Resonance in Biological Systems; State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics; Wuhan Institute of Physics and Mathematics; Chinese Academy of Sciences; Wuhan 430071 P. R. China
3. School of Optoelectronic Information; University of Electronic Science and Technology of China College of Chemistry; Chengdu 610054 P. R. China
4. Analytical and Testing Center; Sichuan University; Chengdu 610064 P. R. China