1. Departamento de Materiales y Minerales; Universidad Nacional de Colombia-Medellin; Calle 75 No. 79A-51, Bloque 17 Medellín Colombia
2. Department of Mechanical Engineering; Polymer Engineering Center; University of Wisconsin-Madison; 1513 University Avenue Madison Wisconsin 53706
3. Institute for Molecular Engineering; University of Chicago; 5640 South Ellis Avenue Chicago Illinois 60637