On the Coexistence Theory of Slag Structure Zhang Jian Abstract Contribution of N.M.Chuiko to the development of the coexistence th- eory of slag structure.The insufficiency of the previous demonstration for this theory.Further fundamental facts confirming the coexistence theory of slag structure (the facts of crystal chemistry,the difference in electric conductivity of various slags,the liquid miscibility gaps of MeO-SiO2 bin- nary slags,the peaks on the temperature composition diagram of MeO-SiO2 binarg slags,the viscosity-composition diagram of CaSiO,-CaF2 system,the relation between standard free energy of formafion of silicates and mass ac- tion concentrations).some examples about the use of the above mentioned theory eqnilibrum between FeO-Fe2O,-SiO2 and H2O+H2,CaO-SiO2,dis- tribution of sulfur between CaO-MgO-FeO-Fe2O,-SiO:-S and liquid iron). 食 和 29毛 一 ‘ 电 。 。 。 ， ， 爪 一 ， 一 ， 一 。 一 ， 一 。 一 一 ， 一 ， 一 一 一 一 一 乍工肠么 甲 趁 会和