1. State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan National Laboratory for OptoelectronicsNational Center for Magnetic Resonance in Wuhan, Key Laboratory of Magnetic Resonance in Biological Systems, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences (CAS) Wuhan Hubei 430071 China
2. University of Chinese Academy of Sciences Beijing 100049 China
3. Beijing Nuclear Magnetic Resonance Center, College of Chemistry and Molecular Engineering, College of Life Sciences, Peking University Beijing 100871 China