1. Institute of Applied Materials, Department of Chemical Engineering; University of Pretoria; Pretoria South Africa
2. Laboratoire des Matériaux Polymères Avancés (LMPA), Faculté de Technologie, Université de Bejaia; Bejaia Algeria
3. Interdisciplinary Center for Transfer-oriented Research in Natural Sciences (IWE TFN), Martin Luther University Halle-Wittenberg; Halle Germany