1. R&D Center for Membrane Technology and Department of Chemical Engineering, Chung Yuan Christian University, Chung-Li, Taoyuan 320, Taiwan
2. School of Chemical, Biological and Materials Engineering and Sciences, Mapua University, Intramuros, Muralla St., Manila 1002, Philippines
3. Division of Urology, Department of Surgery, Changhua Christian Hospital, 135 Nanxian St., Changhua 500, Taiwan
4. Laboratoire de Génie Chimique, Université Paul Sabatier, 118 route de Narbonne, 31062 Toulouse Cedex 9, France