Peiqiang Xu, Yang Jiang*, Yao Chen, Ziguang Ma, Xiaoli Wang, Zhen Deng, Yan Li, Haiqiang Jia, Wenxin Wang and Hong Chen
* Corresponding author: Yang Jiang jiangyang@iphy.ac.cn
Nanoscale Research Letters 2012, 7:141 doi:10.1186/1556-276X-7-141