1. Environmental Engineering and Science, Department of Chemical and Environmental Engineering, University of Cincinnati, Cincinnati, Ohio 45221, United States
2. Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208, United States
3. Department of Environmental Sciences, University of California, Riverside, California 92521, United States
4. Faculty of Geosciences and Environmental Engineering, Southwest Jiaotong University, Chengdu 611756, China