1. Graduate Research Assistant, Dept. of Chemical Engineering, Univ. of Texas at Austin, 1 University Station C0400, Austin, TX 78712-0231. E-mail: davidcas@che.utexas.edu
2. Professor, Dept. of Chemical Engineering, Univ. of Texas at Austin, 1 University Station C0400, Austin, TX 78712-0231 (corresponding author). E-mail: edgar@che.utexas.edu