1. a Dalian Municipal Design and Research Institute of Environmental Science , Dalian, Liaoning , P.R. China
2. b Experimental Center , Shenyang Normal University , Shenyang Liaoning , China
3. c Institute of Environmental and Biological Engineering, Liaoning University of Petroleum and Chemical Technology , Fushun, Liaoning , P.R. China
4. d Engineering Research Institute, Tokyo University , Japan