1. a Chemistry and Chemical Engineering Department, Faculty of Applied Chemistry and Engineering, ‘Ovidius’ University from Constanta, Constanta, Romania
2. b Department of Economic Engineering, Faculty of Entrepreneurship, Business Engineering and Management, University Politehnica of Bucharest, Bucharest, Romania
3. c Department of Fundamental Sciences and Humanities, Constanta Maritime University, Constanta, Romania
4. d Department of Economics, Faculty of Entrepreneurship, Business Engineering and Management, University POLITEHNICA of Bucharest, Bucharest, Romania