1. Andrx Pharmaceuticals, Inc., 4955 Orange Drive, Fort Lauderdale, Florida 33314, Department of Chemical Engineering, Sogang University, Seoul 121-742, Korea, Institut fur Verfahrenstechnik TVT, Martin-Luther-Universität, Halle D-06099, Germany, and Department of Chemical Engineering, Illinois Institute of Technology, 3301 S. Dearborn, Chicago, Illinois 60616