1. Department of Plasma Physics and Technology, Faculty of Science, Masaryk University, Kotlářská 2, 611 37 Brno, Czech Republic
2. Department of Mathematics and Physics, Faculty of Military Technology, University of Defence in Brno, Kounicova 65, 662 10 Brno, Czech Republic
3. Centre of Polymer Systems, Tomas Bata University in Zlín, Trida Tomase Bati 5678, 760 01 Zlín, Czech Republic