1. Key Laboratory of Comprehensive and Highly Efficient Utilization of Salt Lake Resources, Qinghai Institute of Salt Lakes, Chinese Academy of Sciences, Xining 810008, P. R. China
2. Key Laboratory of Salt Lake Resources Chemistry of Qinghai Province, Chinese Academy of Sciences, Xining 810008, P. R. China
3. Qinghai Engineering and Technology Research Center of Comprehensive Utilization of Salt Lake Resources, Chinese Academy of Sciences, Xining 810008, P. R. China