1. Key Laboratory of Magnetic Resonance in Biological Systems, National Center for Magnetic Resonance in Wuhan, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, China
2. School of Chemical and Environmental Engineering, Hubei University for Nationalities, Enshi 445000, China
3. Department of Chemistry and Chemical Biology, University of New Mexico, Albuquerque, New Mexico 87131, USA
4. Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore 637371