1. National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology; Key Laboratory of Green Process and Engineering; Institute of Process Engineering; Chinese Academy of Sciences; Beijing 100190 China
2. University of Chinese Academy of Sciences; No. 19A Yuquan Road Beijing 100049 China
3. Georgia Institute of Technology; School of Materials Science and Engineering; 771 Ferst Drive, N.W. Love Bldg., Rm 372 Atlanta GA 30332-0245 USA
4. Nanocomp Technologies Inc.; Merrimack NH 03054 USA