| 초록 |
Effects of heat-treatment, crystallographic structures, nonstoichiometry, thermal properties, and electrical conductivities of Sr1-xLaxTiO3-ysystem prepared in air were studied with slightly increasing the mole fractionsof La by 0.02mole(x=0.00, 0.02, 0.04, 0.06 and 0.08). Each sample showed typical perovskite structure with cubic symmetries and their cell parameters were in the range of a=3.905-4.029Å. With increasing temperature from 36℃ to 500℃, the five samples steadily lost their weights from the beginnig of the heating, which was probably caused by the outgoing of O2. The amounts of Ti3+ were measured by the oxidation-reduction titration using the transition metal ions such as Fe3+, and finally we could determine the nonstoichiometric formulas of all the samples. |
