1. College of Chemistry and Environmental Science, Lanzhou City University, 11 Jiefang Road, Lanzhou 730070, China
2. College of Chemistry and Chemical Engineering, Ningxia Normal University, 161 Beiguan west Road, Guyuan 756000, China
3. Key Laboratory of Eco-Environment-Related Polymer Materials of Ministry of Education, Key Laboratory of Polymer Materials of Gansu Province, College of Chemistry and Chemical Engineering, Northwest Normal University, 967 Anning East Road, Lanzhou 730070, China