1. a Department of General and Inorganic Chemistry , University of Pardubice , 53210 , Pardubice , Czech Republic
2. b Departamento de Fisica de la Materia Condensada , Universidad de Cadiz , Apdo. 40, 11.510, Puerto Real , Cadiz , Spain
3. c Departamento de Ingenieria Electrica , Universidad de Cadiz , Apdo. 40, 11.510, Puerto Real , Cadiz , Spain
4. d Department of Electrical Engineering , University of Edinburgh , Edinburgh , EH9 3JL , Scotland , UK
5. e Department of Electrical Engineering , University of Saskatchewan , Saskatoon , S7N 5A9 , Canada