1. Polymer Reactions Engineering Department, Faculty of Chemical Engineering, Tarbiat Modares University, P.O. Box 14155-111, Tehran 14117-13116, Islamic Republic of Iran
2. Department of Mechanical Science and Engineering, Graduate School of Engineering, Hiroshima University, 1-4-1 Kagamiyama, Higashihiroshima, Hiroshima, 739-8527, Japan