1. Institute of Environmental Engineering, National Yang Ming Chiao Tung University, 1001, University Rd., Hsinchu City 30010, Taiwan
2. Department of Chemistry, National Tsing Hua University, 101, Sec 2, Kuang-Fu Rd., Hsinchu 300044, Taiwan
3. Department of Civil and Environmental Engineering, University of Michigan, 1351 Beal Ave. Ann Arbor, Michigan 48109, United States