1. Department of Chemical Engineering; Queen's University; Kingston ON Canada
2. Centro de Investigación en Química Aplicada (CIQA); Blvd. Enrique Reyna 140 Saltillo, Coahuila 25253 México
3. Facultad de Ciencias Químicas; Universidad Autónoma de Coahuila; Saltillo México
4. Center for Macromolecular Engineering; Department of Chemistry, Carnegie Mellon University; 4400 Fifth Ave. Pittsburgh PA 15213 USA