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The molar heat capacity of PbVO and PbVO in the temperature range 350-1000 K was measured by differential scanning calorimetry. It was determined that the plot C = f( T) for PbVO has an extremum within the range 416-516 K, which is due to a phase transition. A correlation was found between the heat capacity and composition of oxides in the PbO-VO system. The data obtained allowed one to predict the specific heat capacity value for Pb(VO). [ABSTRACT FROM AUTHOR]

The heat capacities of PbVO and Pb(VO) as a function of temperature in the range 350-965 K have been studied by the differential scanning calorimetry method. The C = f( T) curve for PbVO is described by the equation C = (230.76 ± 0.51) + (73.60 ± 0.50)×10 T − (18.38 ± 0.54)×10 T in the entire temperature range. For Pb(VO), there is a well-pronounced extreme point in the C = f( T) curve at T = 371.5 K, which is caused by the existence of a structural phase transition. The thermodynamic properties of the oxide compounds have been calculated. [ABSTRACT FROM AUTHOR]

Erbium titanate with a pyrochlore structure has been synthesized by a ceramic method from stoichiometric ErO-TiO mixtures at 1673-1773 K. The high-temperature heat capacity of ErTiO (320-1000 K) has been studied by differential scanning calorimetry. The thermodynamic functions of this oxide compound-enthalpy and entropy changes and reduced Gibbs-have been calculated from the experimental dependence C = f( T). [ABSTRACT FROM AUTHOR]

Ternary oxide GdBiGeO was synthesized by a ceramic method. The heat capacity of crystalline gadolinium bismuth germanate as a function of temperature in the range 373-1000 K has been studied by differential scanning calorimetry. It has been demonstrated that the temperature dependence of the heat capacity can be described by the classical Maier-Kelley equation. From the experimental C = f( T) data, the thermodynamic functions (the change in enthalpy and entropy) of ternary oxide GdBiGeO have been calculated. [ABSTRACT FROM AUTHOR]

The molar heat capacity of BiVO has been measured in the range 356-980 K by the differential scanning calorimetry method. There is an extreme point in the C = f( T) curve at about T = 532 K, which is caused by the existence of a phase transition. The thermodynamic properties of bismuth orthovanadate have been determined from the experimental data. [ABSTRACT FROM AUTHOR]