1. Department of Chemistry, College of Natural and Computational Sciences, Debre Markos University, P.O. Box 269, Debre Markos, Ethiopia
2. Graduate Institute of Applied Science and Technology, National Taiwan University of Science and Technology, Taipei 106, Taiwan, Republic of China
3. Advanced Membrane Materials Center, National Taiwan University of Science and Technology, Taipei 106, Taiwan, Republic of China
4. R&D Center for Membrane Technology, Chung Yuan Christian University, Chungli, Taoyuan 320, Taiwan, Republic of China