1. Institute
of Coal Chemistry, Chinese Academy of Sciences, 27 South Taoyuan Road, Taiyuan 030001, Shanxi, P. R. China
2. University of
Chinese Academy of Sciences, 19A Yuquan
Road, Beijing 100049, P. R. China
3. Engineering
Research Center of Ministry of Education for Fine Chemicals, Shanxi University, 92 Wucheng Road, Taiyuan 030006, Shanxi, P. R. China