a
Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province, State Key Laboratory of Applied Organic Chemistry and College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, P. R. China
E-mail: zengzhzh@yahoo.com.cn
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Fax: +86931 8912582
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Tel: +86 931 8912596
b
School of Basic Medical Sciences, Lanzhou University, Lanzhou 730000, P. R. China