1. Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, No. 27, Shanda South Road, Jinan 250100, Shandong, China, Tel. ; Fax:
2. Key Laboratory of Inorganic Chemistry in Universities of Shandong, Department of Chemistry and Chemical Engineering, Jining University, Qufu 273155, Shandong, China