1. Gansu International Scientific and Technological Cooperation Base of Water Retention Chemical Functional Materials, College of Chemistry and Chemical Engineering, Northwest Normal University, Lanzhou, Gansu 730070, People's Republic of China
2. Gansu Police Vocational College, Lanzhou, Gansu 730046, China
3. College of Chemistry and Chemical Engineering, Qinghai Normal University, Xining, Qinghai, 810016, China