1. College of Materials and Chemical Engineering Key laboratory of inorganic nonmetallic crystalline and energy conversion materials China Three Gorges University Yichang 443002 Hubei province P. R. China
2. College of Chemistry and Chemical Engineering Jinggangshan University Ji'an 343009 P. R. China
3. College of Environmental and Chemical Engineering Jiangsu University of Science and Technology Zhenjiang 212003 P. R. China