1. State Key Laboratory of Heavy Oil Processing, Institute of New Energy College of Chemical Engineering China University of Petroleum (East China) Qingdao 266580 P. R. China
2. College of Materials Science and Engineering China University of Petroleum (East China) Qingdao 266580 P. R. China
3. State Key Laboratory of Molecular Engineering of Polymers and Department of Macromolecular Science Fudan University Shanghai 200433 P. R. China