1. Key Laboratory for the Chemistry and Molecular Engineering of Medicinal Resources; Guangxi Normal University; Guilin 541004 P.R. China
2. College of Chemistry and Chemical Engineering; Shaanxi University of Science & Technology; Xi'an 710021 P.R. China
3. Shanghai Synchrotron Radiation Facility; Shanghai Institute of Applied Physics; Chinese Academy of Sciences; Shanghai 201204 P.R. China
4. Institut de Chimie de Strasbourg; CNRS-UMR 7177; Université de Strasbourg; 67070 Strasbourg France
5. College of Chemistry & Chemical Engineering; Hubei University; Wuhan 430062 P.R. China