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Thermodynamic properties of polycrystalline powders of ruthenium dichalcogenides have been studied using calorimetric isobaric heat capacity measurements in a wide temperature range. The adiabatic and differential scanning calorimetry data for ruthenium disulfide and ruthenium diselenide have been used to determine standard thermodynamic functions (heat capacity, entropy, enthalpy increment, and reduced Gibbs energy) of these compounds in the range 10–965 K. At 298.15 K, the functions of RuS2 are as follows: = 60.82 ± 0.12 J/(K mol), S° = 56.05 ± 0.11 J/(K mol), Н°(298.15 K) − Н°(0) = 9.75 ± 0.02 kJ/mol, and Ф° = 23.34 ± 0.05 J/(K mol). For RuSe2, we have obtained = 69.96 ± 0.14 J/(K mol), S° = 80.62 ± 0.16 J/(K mol), Н°(298.15 K) − Н°(0) = 13.05 ± 0.03 kJ/mol, and Ф° = 36.85 ± 0.08 J/(K mol). The data obtained above 298 K have been used to determine empirical coefficients of the Maier–Kelley and Khodakovsky equations. The absolute entropies obtained in this study for the ruthenium dichalcogenides, in combination with literature data, have made it possible to evaluate the Gibbs energy of formation of RuS2(cr) and RuSe2(cr) at 298.15 K. [ABSTRACT FROM AUTHOR]

In this paper, we report the synthesis of crystalline ruthenium ditelluride (RuTe2) and its thermodynamic properties in the range from 10 to 965 K, evaluated from its isobaric heat capacity Cp determined using calorimetry. At low temperatures, between 6.86 and 335.11 K, the heat capacity of the synthesized material—pure, free of impurities and foreign phases—was determined by adiabatic calorimetry. In the range 315.3–965.3 K, Cp was determined by differential scanning calorimetry. The data obtained above 298 K have been used to determine empirical coefficients of the Maier–Kelley and Khodakovsky equations. In the range 10–965 K, we have evaluated the standard thermodynamic functions: heat capacity, entropy, enthalpy increment, and reduced Gibbs energy. At 298.15 K, we have obtained = 72.43 ± 0.14 J/(K mol), S° = 94.94 ± 0.19 J/(K mol), Н°(298.15 K) − Н°(0) = 14.60 ± 0.03 kJ/mol, and Ф° = 45.97 ± 0.09 J/(K mol). Using the absolute entropy determined by us and data in the literature and handbooks, we have estimated the standard Gibbs energy of formation of RuTe2: ΔfG°(RuTe2, cr, 298.15) = −130.5 ± 2.9 kJ/mol. [ABSTRACT FROM AUTHOR]

In this paper, we report the synthesis of crystalline platinum ditelluride, PtTe2, a synthetic analog of the mineral moncheite, and its thermodynamic properties. Using the isobaric heat capacity of PtTe2 determined in the range 2–305 K by the relaxation and adiabatic calorimetry methods, we have evaluated its standard thermodynamic functions: entropy, enthalpy increment, and reduced Gibbs energy. The following parameters have been obtained for PtTe2 at 298.15 K: = 75.11 ± 0.15 J/(K mol), S° = 121.5 ± 0.2 J/(K mol), Н°(298.15 K) − Н°(0) = 16.69 ± 0.03 kJ/mol, and Ф° = 65.55 ± 0.13 J/(K mol). Using data in the literature and handbooks, we have estimated the standard Gibbs energy of formation of PtTe2: ΔfG°(PtTe2, cr, 298.15) = –75.4 ± 0.8 kJ/mol. Fractal analysis of the heat capacity data indicates that PtTe2 has a layered structure and that its Debye temperature is 250 K. [ABSTRACT FROM AUTHOR]

We have for the first time determined the temperature dependence of heat capacity for aurostibite, AuSb2, by adiabatic calorimetry and calculated its standard thermodynamic functions in a wide temperature range. At a temperature of 298.15 K, we have obtained = 76.01 ± 0.15 J/(mol K), S° = 133.4 ± 0.3 J/(mol K), Н°(298.15 K) − Н°(0)= 17.39 ± 0.03 kJ/mol, and Ф° = 75.02 ± 0.15 J/(mol K). Using previously reported data and the present results, we have found ΔfG°(298.15) = −11.36 ± 0.90 kJ/mol. [ABSTRACT FROM AUTHOR]

The temperature-dependent heat capacity of vysotskite, PdS, has been determined for the first time by adiabatic, relaxation, and differential scanning calorimetry in a wide temperature range and standard thermodynamic functions of PdS have been calculated. The 298.15-K values thus obtained are = 43.65 ± 0.09 J/(mol K), S° = 51.98 ± 0.10 J/(mol K), Н°(298.15 К) − Н°(0) = 8.03 ± 0.02 kJ/mol, and Ф° = 25.03 ± 0.05 J/(mol K). Using the present results and data in the literature, we obtained ΔfH°(PdS, 298.15 K) = –74.0 ± 1.0 kJ/mol and ΔfG°(PdS, 298.15 K) = –68.7 ± 1.0 kJ/mol. [ABSTRACT FROM AUTHOR]

The thermodynamic properties of crystalline platinum disulfide have been studied in the range from 5 to 875 K. The isobaric heat capacity of PtS2 has been determined by two methods: by adiabatic calorimetry from 5.32 to 344.96 K and by differential scanning calorimetry in the range 344.6–874.6 K. Using the experimental Cp(T) data, we evaluated the standard thermodynamic functions of platinum disulfide in a wide temperature range. The high-temperature Cp measurement results have been used to investigate regression models based on the Maier–Kelley and Khodakovsky equations for the temperature dependence of its isobaric heat capacity in the range from 298 to 875 K. The Debye characteristic temperature ΘD of PtS2 has been evaluated as a function of temperature. [ABSTRACT FROM AUTHOR]

In this paper, we present the results of the application of new methods of monitoring and diagnostics based on a computer analysis of multiscale dynamic thermographic patterns. Depending on the size of the inspected area, as well as the nature, location, orientation, and size of defects, various energy sources, such as an airflow, focused laser beam, and point contact, were used for probing dynamic heating of the product under control. The nonstationary thermal image of the monitored area was recorded by a high-resolution thermal camera and then analyzed by using original model approaches and developed specialized software. The development of defects was initiated by a calibrated local power load using the built-in force generator. This allowed identifying dynamic (prone-to-growth) defects and assessing the degree of their danger for further operation and the residual resource of the product. Using the proposed methods, defects of various types (cracks, delaminations, detachments, and degradation of coatings, defects in welding and adhesive joints, deposits of transported substances, etc.), sizes (from fractions to tens of millimeters), and location in the product (near both the outer and inner surfaces of vessels, pipelines, reactors, tanks, etc.) can be detected and quantitatively characterized. The developed techniques also allow determining the thermophysical characteristics of the material, in particular, the thermal diffusivity coefficient with an accuracy better than ±3%. [ABSTRACT FROM AUTHOR]

The Pourbaix diagrams of the Cu-HSO-HO and Co-HSO-HO systems have been refined and the stability regions of sulfite phases in the diagrams have been identified. Phase diagrams of copper(I) copper( II) and copper(I) cobalt(II) double sulfites have been mapped out. The double sulfites CuSO · СuSO and CuSO · СoSO have been isolated from an aqueous solution saturated with sulfur dioxide. We have obtained electron paramagnetic resonance spectra of the double sulfite CuSO · СoSO and characterized it by X-ray diffraction, IR spectroscopy, particle size analysis, and thermogravimetry. A foundation has been laid for the thermodynamic prediction of the synthesis of the CuSO · MSO (M = Cu, Co) double sulfites. [ABSTRACT FROM AUTHOR]

The isobaric heat capacity of the ErO · 2ZrO solid solution has been determined by adiabatic calorimetry and differential scanning calorimetry, and the enthalpy increment, entropy, and reduced Gibbs energy change of the solid solution have been calculated in the temperature range 6-1400 K with no allowance for the low-temperature (<6 K) magnetic transformations. [ABSTRACT FROM AUTHOR]

The isobaric heat capacity of p-SmZrO (pyrochlore phase) has been determined in the temperature range 10-1400 K using adiabatic, differential scanning, and relaxation calorimetry, and its enthalpy increment, entropy, and reduced Gibbs energy have been calculated with allowance for the contributions of its low-temperature magnetic transformations. [ABSTRACT FROM AUTHOR]

The low-temperature heat capacity of DyO · 2ZrO and HoO · 2ZrO has been determined by adiabatic calorimetry in the temperature range 10-340 K. The results have been used to calculate the entropy, enthalpy increment, and reduced Gibbs energy of the zirconates without taking into account their low-temperature magnetic transformations. [ABSTRACT FROM AUTHOR]

The temperature-dependent heat capacity of aluminum oxynitride has been determined by adiabatic calorimetry in the range 0-340 K. Smoothed heat capacity data have been used to calculate its thermodynamic functions: entropy, enthalpy increment, and reduced Gibbs energy. The results are C(298.15 K) = 891.0 ± 1.8 J/(mol K), S(298.15 K) = 614.4 ± 1.2 J/(mol K), H(298.15 K) − H(0) = 117.3 ± 0.2 kJ/mol, and Φ(298.15 K) = 221.0 ± 1.8 J/(mol K). [ABSTRACT FROM AUTHOR]

The fractal model of heat capacity is shown to be applicable to GaSe, GaSe, GaTe, GaTe, InSe, and InTe. The parameters of the model are determined: characteristic temperature and temperature-dependent multifractal (fracton) dimension. [ABSTRACT FROM AUTHOR]

The heat capacity of ɛ-GaSe has been determined by differential scanning calorimetry in the temperature range 300-700 K. Smoothed heat capacity data have been used to evaluate the thermodynamic functions of gallium monoselenide (entropy, enthalpy increment, and reduced Gibbs energy). [ABSTRACT FROM AUTHOR]

The thermodynamic activities of brass CuZn17Si3 components are calculated. The potential-pH diagrams for the brass CuZn17Si3-HO system for 25°C, a total air pressure of 1 bar, and various ions activities in solution are plotted. The thermodynamic features of the chemical and electrochemical stability of brass CuZn17Si3 are analyzed. It is shown that high corrosion resistance of brass is achieved with respect to the formation of a protective film of ZnSiO on its surface. [ABSTRACT FROM AUTHOR]

The heat capacity of LiNiO ( x = 0.40–0.76) oxides has been measured using an adiabatic calorimeter, and their thermodynamic functions have been determined. The results indicate that the lithium nickelate solid-solution series contains a two-phase region and that near-stoichiometric LiNiO has a layered structure, in accordance with earlier results. [ABSTRACT FROM AUTHOR]

Methodical bases of specular-reflection scanning spectrotomography for diagnostics of phase-inhomogeneous surface layers are presented. Digital optical images of a metal surface with an inhomogeneous layer, obtained at different wavelengths, can be processed using optical spectrotomography algorithms modified as applied to reflectometry. This allows thickness and chemical composition control of inhomogeneous surface layers. The method was tested for nondestructive evaluation of thickness and chemical composition of an oxide layer on the surface of thermally treated Kh18N10T steel. [ABSTRACT FROM AUTHOR]

The heat capacity of V3Te4 has been measured as a function of temperature using an adiabatic calorimeter, and its thermodynamic properties were evaluated. We have determined the Debye characteristic temperature and fracton dimension of crystalline V3Te4. [ABSTRACT FROM AUTHOR]

The methods of adiabatic and differential scanning calorimetry are used to measure the temperature dependence of the heat capacity. Thermodynamic functions are calculated for VTe2. The Debye characteristic temperature is determined and the fractal dimension of crystalline vanadium ditelluride is calculated. [ABSTRACT FROM AUTHOR]

The heat capacity of InSe has been measured at temperatures from 11.14 to 325.26 K using an adiabatic calorimeter. The results differ significantly from earlier data (by ∼2.2% at 200 K). The smoothed heat capacity data have been used to evaluate temperature-dependent thermodynamic functions (entropy, enthalpy increment, and reduced Gibbs energy) of indium selenide. Its thermodynamic properties under standard conditions are C (198.15 K) = 49.43 ± 0.10 J/(K mol), S 0(298.15 K) = 82.20 ± 0.16 J/(K mol), H 0(298.15 K) − H0(0) = 10.94 ± 0.02 kJ/mol, and Φ0(298.15 K) = 45.50 ± 0.09 J/(K mol). The Debye characteristic temperature of InSe evaluated from the heat capacity data is 275 ± 15 K. [ABSTRACT FROM AUTHOR]

The heat capacity of Ga2Te3 is measured from 9 to 310 K using adiabatic calorimetry. The smoothed heat capacity data are used to evaluate temperature-dependent thermodynamic functions (entropy, enthalpy increment, and reduced Gibbs energy) of Ga2Te3. Its thermodynamic properties under standard conditions are C (298.15 K) = 119.3 ± 0.2 J/(K mol), S 0(298.15 K) = 209.8 ± 0.4 J/(K mol), H 0(298.15 K) – H 0(0) = 27.19 ± 0.05 kJ/mol, and Φ0(298.15 K) = 118.6 ± 0.2 J/(K mol). The Debye characteristic temperature of Ga2Te3 evaluated from the heat capacity data is 280 ± 20 K. [ABSTRACT FROM AUTHOR]

The heat capacity of GaTe is measured from 6.8 to 337.95 K using adiabatic calorimetry. The results are used to calculate the heat capacity, entropy, enthalpy increment, and reduced Gibbs energy of GaTe in the temperature range 10–320 K under standard conditions. The 298.15-K thermodynamic properties of GaTe are C (298.15 K) = 48.96 ± 0.10 J/(K mol), S 0(298.15 K) = 81.30 ± 0.16 J/(K mol), H 0(298.15 K) − H 0(0 K) = 10.84 ± 0.02 kJ/mol, and Φ0(298.15 K) = 44.95 ± 0.09 J/(K mol). [ABSTRACT FROM AUTHOR]

The heat capacity of Ga2Se3 is measured from 14 to 320 K by adiabatic calorimetry. The smoothed heat capacity data are used to evaluate temperature-dependent thermodynamic functions (entropy, enthalpy increment, and reduced Gibbs energy) of gallium selenide. Under standard conditions, the thermodynamic properties of Ga2Se3 are C (298.15 K) = 120.8 ± 0.2 J/(K mol), S 0(298.15 K) = 180.4 ± 0.4 J/(K mol), H 0(298.15 K) - H 0(0) = 25.32 ± 0.05 kJ/mol, and Φ0(298.15 K) = 95.52 ± 0.19 J/(K mol). The Debye characteristic temperature of Ga2Se3 evaluated from heat capacity data is 340 ± 10 K. [ABSTRACT FROM AUTHOR]

Lanthanum stannate with the pyrochlore structure and a crystallite size in the range 100–400 nm has been prepared by solid-state synthesis. We have optimized synthesis parameters for obtaining a ceramic material. The heat capacity of La2Sn2O7 has been determined for the first time using adiabatic and differential scanning calorimetry techniques in the range 19–1300 K, and the stannate has been shown to undergo no structural transitions in this range. We have calculated temperature-dependent standard thermodynamic functions of La2Sn2O7 and evaluated the standard Gibbs energy of formation of this compound from its constituent elements at 298.15 K. [ABSTRACT FROM AUTHOR]

The thermodynamic functions of YbPO have been determined experimentally in the temperature range 6-1745 K. The results have been used to calculate temperature-dependent heat capacity, entropy, enthalpy increment, and reduced Gibbs energy of YbPO in the range 6-1800 K. The Gibbs energy of formation of ytterbium orthophosphate (Δ G(298.15 K)) has been determined. [ABSTRACT FROM AUTHOR]

The heat capacity of ScVO has been determined by adiabatic calorimetry at temperatures from 14.52 to 347.13 K, and smoothed heat capacity data have been used to evaluate its thermodynamic functions (entropy, enthalpy increment, and reduced Gibbs energy). At 298.15 K, the thermodynamic functions of scandium orthovanadate are C(298.15 K) = 110.5 ± 0.1 J/(mol K), S(298.15 K) = 110.9 ± 0.1 J/(mol K), H(298.15 K) − H(0) = 18.53 ± 0.01 kJ/mol, and Φ(298.15 K) = −[ G(298.15 K)/298.15] = 48.75 ± 0.12 J/(mol K). The calculated Gibbs energy of formation of scandium orthovanadate from its constituent elements is Δ G(ScVO, 298.15 K) = −1644.0 ± 2.2 kJ/mol. [ABSTRACT FROM AUTHOR]

The heat capacity of GdVO has been determined by adiabatic calorimetry in the range 5-345 K. The present experimental data and earlier results have been used to evaluate the thermodynamic functions of gadolinium orthovanadate ( C( T), S( T), H( T) − H(0), and Φ( T)) as functions of temperature (5-350 K). Its Gibbs energy of formation is determined to be Δ G(GdVO, 298.15 K) = −1684.5 ± 1.6 kJ/mol. [ABSTRACT FROM AUTHOR]

The heat capacities of lanthanum and lutetium orthovanadates have been measured at temperatures from 7 to 345 K using an adiabatic calorimeter. No anomalies have been detected in the heat capacity data. The thermodynamic functions ( C( T), S0( T), and H0( T) − H0(0)) of the two compounds have been calculated in the temperature range studied, and their Debye characteristic temperatures have been estimated. [ABSTRACT FROM AUTHOR]

We have studied the gamma sensitivity of single-crystal CVD diamond neutron detectors using a Cf neutron source placed in a moderator. It has been shown that a major contribution to the count rate of the detectors is made by the gamma rays from the source. We have compared the count rates of a detector with a B boron isotope-based slow-neutron converter and without it. With allowance for the theoretically calculated detection efficiency, the difference between the count rates is consistent with the fraction of slow neutrons measured using a scintillation detector. [ABSTRACT FROM AUTHOR]

The heat capacity of dysprosium orthovanadate has been determined by adiabatic calorimetry in the range 6.12-343.26 K. The present and earlier data have been used to calculate the thermodynamic functions of DyVO in the temperature range 0-350 K. We have determined the absolute entropy and Gibbs energy of formation of dysprosium orthovanadate: S(298.15 K) = 148.34 ± 0.11 J/(mol K), Δ G(298.15 K) = −1671.6 ± 2.1 kJ/mol. An anomaly has been detected at temperatures below 42 K, due to the Jahn-Teller phase transformation ( T = 14.42 K). We have determined the thermodynamic characteristics of the transformations in the temperature range 0-42.63 K. [ABSTRACT FROM AUTHOR]