1. Faculty of Industrial Chemistry and Environmental Engineering, “Politehnica” University of Timisoara, 2 Victoriei Sq., 300006, Timisoara, Romania
2. Faculty of Physics, West University of Timisoara, 4 Parvan Bd., 300223 Timisoara, Romania
3. Faculty of Chemistry, “Al. I. Cuza” University, 11 Carol I Bd., 700506 Iasi, Romania