1. College of Chemical Engineering; Northwest University for Nationalities; Lanzhou Gansu 730030 China
2. Institute of Arid Meteorology; CMA; Key laboratory of Arid Climatic Change and Reducing Disaster of Gansu Province; Key Open Laboratory of Arid Climatic Change and Disaster Reduction of CMA; Lanzhou 730020 China
3. Gansu Key Laboratory of Polymer Materials, College of Chemistry and Chemical Engineering, Key Laboratory of Eco-environment-related Polymer Materials; Ministry of Education; Northwest Normal University; Lanzhou Gansu 730070 China