1. Department of Chemical and Petroleum Engineering, University of Pittsburgh, Pittsburgh, Pennsylvania 15261, Department of Chemical Engineering, Clemson University, Clemson, South Carolina 29634, Department of Chemical Engineering, Hampton University, Hampton, Virginia 23668, Research Triangle Institute, P.O. Box 12194, Research Triangle Park, North Carolina 27709-2194, and Department of Chemical Engineering, North Carolina State University, Raleigh, North Carolina 27695