1. Department of Chemical and Biomolecular Engineering; National University of Singapore; 4 Engineering Drive 4 Singapore 117585 Singapore
2. Institute of Industrial Catalysis; College of Chemical Engineering; Zhejiang University of Technology; Hangzhou 310014 P.R. China
3. School of Chemical Engineering; Guizhou Institute of Technology; 1 Caiguan Road, Yunyan District 550003 Guiyang P.R. China