The parabolic rate constant for the solid-state reaction of 1/2La2O3 + 1/2Cr2O, = LaCrO3 was measured at temperatures between 1483 and 1688 K in air and at 1695 K in oxygen pressures between 2.1 X i0 and 1.5 X 10 Pa. According to Wagner's theory, the diffusion coefficient of La in LaCrO3 was evaluated using the parabolic rate constant and the standard Gibbs energy change of the reaction. The oxygen pressure dependence of the diffusion coefficient is given by D,s./m2 s' = 4.5 X l0' (P02/Pa)31'6 a03 + 1.6 x 1016 a0 (T = 1695 K)where acr,o is the activity of Cr203 and P0 is the oxygen pressure. The temperature dependence of the diffusion coefficient of lanthanum ion in LaCrO3 is given by 2 -' -l ( 480 kJ mol' 316 18 D /m s = a3 x 10 expl -

The nitride capacities in CaO‐TiO2‐TiO1.5 slags, and nitrogen distribution ratio between these slags and liquid Cu (LN = (mass‐% N)/[mass‐% N]) were measured by a gas‐slag‐metal equilibration technique, using a Mo crucible in the temperature range of 1823 to 1923 K under controlled partial pressures of oxygen and nitrogen . The values for , (mass‐% Ti3+)/(mass‐% Ti4+) ratio, and solubility of TiN in CaO‐TiO2‐TiO1.5 slags were obtained as a function of slag composition (XCaO = 0.24 ∼ 0.39) and temperature. Activity coefficients of TiN were evaluated from the values for activity coefficients of Ti in liquid Cu which were calculated from the results of TiN saturation experiments.

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