1. College of Chemistry and Chemical Engineering, China University of Petroleum (East China), Qingdao 266580, P. R. China
2. State Key Laboratory of Heavy Oil Processing, China University of Petroleum (East China), Qingdao 266580, P. R. China
3. Advanced Chemical Engineering and Energy Materials Research Center, China University of Petroleum (East China), Qingdao 266580, P. R. China