1. School of Environmental and Biological Science and Technology Dalian University of Technology Dalian 116024, People's Republic of China
2. School of Environmental and Biological Science and Technology, Dalian University of Technology, No. 2, Linggong Road, Dalian 116024, P.R. China. Phone: +86-411-84706140; Fax: +86-411-84706263; E-mail: quanxie@dlut.edu.cn
3. Department of Environmental Science and Technology Northeast Normal University Changchun 130024, People's Republic of China