Chao-Wei Hsu*, Yung-Feng Chen and Yan-Kuin Su*
* Corresponding authors: Chao-Wei Hsu q1897124@mail.ncku.edu.tw - Yan-Kuin Su yksu@mail.ncku.edu.tw
Nanoscale Research Letters 2012, 7:642 doi:10.1186/1556-276X-7-642