Solutocapillary Effects of Sulphur in CaO-Al2O3 Slags, in Marangoni Instability and Convection Onset, Related to the Desulphurization of low Carbon, Aluminium Killed Steels - NITA, Petre Stelian (The Annals of “Dunarea de Jos” University of Galati. Fascicle IX, Metallurgy and Materials Science, 2010)