1. Anhui Province Key Laboratory of Farmland Conservation and Pollution Prevention, School of Resources and Environment, Anhui Agricultural University, Hefei 230036, China
2. Department of Chemistry and Biochemistry, Old Dominion University, Norfolk, Virginia 23529, United States
3. USDA-ARS, National Laboratory for Agriculture and the Environment, Ames, Iowa 50011, United States
4. Department of Chemistry, Brandeis University, Waltham, Massachusetts 02453, United States
5. Agronomy Department, Iowa State University, Ames, Iowa 50011, United States