1. State Key Laboratory of Coal Conversion Institute of Coal ChemistryChinese Academy of Sciences Taiyuan 030001 P.R. China
2. University of Chinese Academy of Sciences Beijing 100049 P.R. China
3. Synfuels China Co. Ltd. Beijing P.R. China
4. Department of Chemistry and Chemical EngineeringTaiyuan Institute of Technology Taiyuan 030008 P.R. China