N. V. Belousova

High-temperature heat capacity of YBiGeO 5 and GdBiGeO 5 in the range 373–1000 K

The oxide YBiGeO5 and GdBiGeO5 compounds have been synthesized by solid-phase synthesis. The high-temperature heat capacity has been measured using differential scanning calorimetry in the range 373–1000 K. The results were used to calculate the thermodynamic properties (the change in the enthalpy and entropy).

High-temperature specific heat of Bi 2 GeO 5 and SmBiGeO 5 compounds

The SmBiGeO5 compound is synthesized from Sm2O3, Bi2O3, and GeO2 by solid-state synthesis with subsequent annealing at 1003, 1073, 1123, 1143, 1173, and 1223 K. The metastable Bi2GeO5 compound is prepared from melt. Temperature dependences of specific heat of Bi2GeO5 (350–1000 K) and SmBiGeO5 (370–1000 K) are measured by differential scanning calorimetry. Basing on the experimental dependences CP = f(T), the thermodynamic functions of the oxide compounds are calculated.

High-temperature heat capacity of oxides of the CuO–V2O5 system

CuV2O6 and Cu2V2O7 compounds have been produced from initial components CuO and V2O5 by solid-phase synthesis. The high-temperature heat capacity of the oxide compounds has been measured using differential scanning calorimetry. The thermodynamic properties (the enthalpy change, the entropy change, and the reduced Gibbs energy) have been calculated using experimental dependences CP = f(T). It is found that there is a correlation between the specific heat capacity and the composition of oxides of the CuO–V2O5 system.

High-temperature heat capacity of Dy2Cu2O5

Data on the heat capacity of Dy2Cu2O5 in the temperature range 346–981 K have been obtained. The experimental data have been used for determining the thermodynamic properties of this oxide compound.

Interaction of ultrafine palladium and platinum powders with chlorocomplexes of gold(III) under hydrothermal conditions

Ultrafine Au-Pd and Au-Pt powders were synthesized under hydrothermal conditions, and their composition and structure were characterized.

High-temperature heat capacity of the oxide compounds in the Bi2O3–V2O5 system

The compounds BiVO4, Bi4V2O11, and Bi12V2O23 have been prepared by solid-state synthesis using stoichiometric mixtures of Bi2O3 and V2O5. The effect of temperature on the heat capacity of the synthesized bismuth vanadates has been studied by differential scanning calorimetry in the range 350–950 K. The Cp(T) curves have extrema at 531.7 K for BiVO4 and at 725.2 and 852.8 K for Bi4V2O11, which are due to polymorphic transformations of these compounds.

Synthesis and study of high-temperature heat capacity of erbium orthovanadate

Orthovanadate ErVO4 has been prepared by solid-phase synthesis from a stoichiometric mixture of high pure V2O5 and chemically pure Er2O3 by multistage calcination in air in the temperature range 873–1273 K. The effect of temperature (380–1000 K) on the heat capacity of orthovanadate ErVO4 was studied by hightemperature calorimetry. Thermodynamic properties of erbium orthovanadate (enthalpy change H°(T)–H°(380 K), entropy change S°(T)–S°(380 K), and reduced Gibbs energy Φ°(T)) have been calculated from the experimental Cp = f(T) data. It has been shown that the specific heat varies in a row of oxides and orthovanadates of Gd-Lu naturally depending on the radius of the R3+ ion within the third and fourth tetrads.

High-temperature heat capacity of orthovanadates Ce1–xBixVO4

Orthovanadates Ce1–xBixVO4 (1 ≥ x ≥ 0) have been produced by solid-phase synthesis from initial oxides CeO2, Bi2O3, and V2O5 upon step-by-step burning. The high-temperature heat capacity of Ce1–xBixVO4 has been measured by differential scanning calorimetry. The experimental data on Cp = f(T) were used to calculate the thermodynamic properties (the enthalpy changes, the entropy changes, and the Gibbs energy).

Heat capacity and thermodynamic properties of europium orthovanadate EuVO4 in the temperature range of 400–1010 K

The molar heat capacity of EuVO4 is measured as a function of temperature by means of high-temperature scanning calorimetry. Thermodynamic properties of the oxide compound (variations in enthalpy Hpo(T) − Hpo(400 K), entropy Spo(T) − Spo(400 K) and reduced Gibbs energy Φpo(T)) are calculated from the experimental data: Cp = f(T).

Carbon-Supported Palladium–Gold Bimetallic Disperse Systems Formed in Aqueous Solutions at 110°С

Various palladium–carbon composites have been manufactured by autoclaving at 170°С to be used as precursors for manufacturing bimetallic particles. The morphology of the manufactured items was comprehensively studied by scanning electron microscopy; the ultrafine metal palladium was found to have particles sizes lying in the range 30–120 nm. The specifics of hydrothermal reduction of gold(III) chloro complexes by palladium–carbon composites at 110°С have been studied. An appreciable increase in gold(III) reduction rate was observed with the use of a palladium–carbon composite relative to the rate observed for ultrafine metallic palladium. Gold is reduced on a palladium–carbon composite to an individual metallic phase.