1. State Key Laboratory of Applied Organic Chemistry Key laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province College of Chemistry and Chemical Engineering Lanzhou University Lanzhou 730000 P. R. China
2. Chemical Science and Engineering College North Minzu University Yinchuan 750000 P. R. China
3. Research Institute of Exploration & Development Tuha Oilfield Company Xinjiang 830000 P. R. China