1. State Key Laboratory of Heavy Oil Processing College of Chemistry and Chemical Engineering China University of Petroleum (East China) Qingdao 266580 P. R. China
2. Key Laboratory of Eco‐chemical Engineering Ministry of Education International Science and Technology Cooperation Base of Eco‐chemical Engineering and Green Manufacturing College of Chemistry and Molecular Engineering Qingdao University of Science and Technology Qingdao 266042 P. R. China
3. College of Science Nanjing Forestry University Nanjing 210037 P. R. China
4. Faculty of Materials Science and Engineering Kunming University of Science and Technology Kunming 650093 P. R. China