1. Department of Applied Chemistry and Engineering of Inorganic Compounds and Environment, Politehnica University Timisoara , Timisoara , Romania
2. Research Institute for Renewable Energy, Politehnica University Timisoara , Timisoara , Romania
3. NanCorr Laboratory, University of Las Palmas de Gran Canaria , Las Palmas de Gran Canaria , Spain
4. Materials Engineering and Welding Department, Transilvania University of Brasov , Brasov , Romania