1. Shaanxi Key Laboratory of Chemical Additives for Industry, College of Chemistry and Chemical Engineering, Shaanxi University of Science and Technology, Xi'an 710021, P. R. China
2. School of Chemical Engineering, Northwest University, Xi'an, Shaanxi, 710069, P. R. China
3. Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey, 07102, USA