1. State Key Laboratory
of Coal Conversion, Institute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan, Shanxi 030001, P. R. China
2. University of the Chinese Academy of Sciences, Beijing 100039, P. R. China
3. Department of Chemical & Biomolecular Engineering, University of Illinois at Urbana−Champaign, 206 Roger Adams Laboratory, MC-712, 600 South Mathews Avenue, Urbana, Illinois 61801, United States