1. Institute of Physics, Jan Dlugosz University, Armii Krajowej 13/15, Czestochowa, Poland
2. Electrical Engineering Department, Czestochowa University of Technology, Armii Krajowej 17, Czestochowa, Poland
3. Institute of Organic Chemistry and Technology, Faculty of Chemical Technology, University of Pardubice, Studentská 573 Pardubice, Czech Republic