1. 1School of Science, Xi'an University of Architecture and Technology, Xi'an 710055, Shaanxi Province, P. R. China
2. 2Luohe Environmental Sanitation Management Agency, Luohe 462000, Henan Province, P. R. China
3. 3Henan Yinge Industrial Investment Co. Ltd, Luohe 462000, Henan Province, P. R. China