1. Shandong Industrial Engineering Laboratory of Biogas Production & Utilization, Key Laboratory of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, Shandong Province, 266101, P. R. China
2. University of Chinese Academy of Sciences, Beijing 100049, P. R. China
3. Shandong Energy Institute, Qingdao 266101, P. R. China
4. Qingdao New Energy Shandong Laboratory, Qingdao 266101, P. R. China
5. Dalian National Laboratory for Clean Energy, Dalian 116023, P. R. China
6. College of Electromechanical Engineering, Qingdao University of Science and Technology, Qingdao 266061, P. R. China