1. National Research Council of Canada, Institute for Chemical Process and Environmental Technology, Ottawa, Ontario, K1A 0R6, Canada, Korea Institute of Science and Technology, Center for Facilitated Transport Membranes and Polymer Physics Lab, P.O. Box 131, Cheongryang, Seoul 130-650, Korea, and Seoul National University, Hyperstructured Organic Materials Research Center and School of Chemical Engineering, Seoul 151-744, Korea