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Density and thermal expansion measurements have been performed for liquid caesium and caesium–bismuth alloys (20–66.7 at.% Bi) in the temperature range from the liquidus curve to 1000 K. A gamma-ray attenuation technique has been used. The concentration dependencies of the volumetric properties of the Cs–Bi liquid system have been constructed. It was established that experimental molar volumes of the liquid alloys are much lower than those of ideal mixtures. The compositional dependence of the volumetric thermal expansion coefficient shows a sharp peak at 25 at.% Bi. Possible reasons for such behaviour are briefly discussed. [ABSTRACT FROM AUTHOR]

Abstract: The enthalpy of solid and liquid Rb73Bi27 alloy is measured via massive isothermal drop calorimeter in the temperature range 430-1225 K. Approximating equations are determined. The isobaric heat capacity and enthalpy change on melting and the solid state transformation are determined. The estimated errors for enthalpy and heat capacity are 0.5 and 1.5%, respectively. It is found that the heat capacity of the liquid alloy falls upon heating above the liquidus. Tables of the recommended values of caloric properties in the range of 298.15 to 1225 K are developed. It is shown that the caloric properties of alloys differ considerably from calculations performed using the laws for ideal solutions. [ABSTRACT FROM AUTHOR]

The mutual diffusion in rubidium-bismuth melts was investigated using a gammaray attenuation technique. The concentration dependence of the interdiffusion coefficient has two maxima in the vicinity of 25 and 50 at.% Bi. The analysis based on Darken’s relation shows that this feature is connected to a tendency for the formation of associated complexes in the liquid alloys. [ABSTRACT FROM AUTHOR]

Enthalpy of solid and liquid intermetallic compound CsBi2 in the temperature range of 430-1225 K was measured by massive isothermal drop calorimeter. Approximation equations were obtained, and isobaric heat capacity and enthalpy change on melting were determined. The tables of recommended values of caloric properties in the range from 298.15 K to 1225 K were developed. The experimental uncertainty of enthalpy and heat capacity measurements were estimated to be within 0.35 and 1.0%, respectively. The obtained results were compared with the calculations according to the laws of ideal solutions. [ABSTRACT FROM AUTHOR]

We investigated the enthalpy of liquid bismuth within the temperature range of 580-1325 K in a massive isothermal drop calorimeter using the mixture method. We obtained the approximation equations and determined the isobaric heat capacity. The estimated errors of the data on the enthalpy and the heat capacity are equal to 0.2% and 0.5%, respectively. The results are compared with the literature data. We confirmed the existence of a heat-capacity minimum of liquid bismuth of approximately 800 K. We show that above 940 K the heat capacity depends linearly on the temperature. We developed tables of the recommended values of the caloric properties within the range from the melting point to 1325 K. [ABSTRACT FROM AUTHOR]

The enthalpy of liquid cesium in the temperature range from 431 to 976 K was measured by a drop method on an isothermal calorimeter. The approximation equation of enthalpy was obtained and the isobaric heat capacity was determined. The estimated errors in the enthalpy and heat capacity data are 0.5% and 1.5%, respectively. The obtained results are compared with the literature data. The position of the minimum heat capacity of liquid cesium was clarified (733 K). Tables of recommended values of caloric properties in the investigated temperature range were developed. [ABSTRACT FROM AUTHOR]

The thermal conductivity λ and the thermal diffusivity a of liquid rubidium were measured by the laser flash method in the temperature interval from the melting point up to 873 K. The measurement error was 4-6%. The data of this paper were compared with the results of other authors. Approximation equations and the table of reference values for the temperature dependence of λ and a have been obtained. The dependence of the Lorentz number on temperature has been calculated. [ABSTRACT FROM AUTHOR]

The speed of sound of the gaseous mixed refrigerant R-134a (57.24 wt.%) - R-227ea (42.76 wt. %) was investigated by the method of ultrasonic interferometer in the temperature range from 293 to 373 K and at pressures from 0.08 to 0.97 MPa. The measurement errors of temperature, pressure, and speed of sound were ±20 mK, ±4 kPa, and ±(0.20-0.35) %, respectively. Approximation dependences of the speed of sound on five isotherms have been obtained, and the experimental data have been compared with calculations using the REFPROP program. [ABSTRACT FROM AUTHOR]

Liquid rubidium enthalpy increment was measured by drop method within the temperature range of 480-1000 K. The approximation equation was obtained and the isobaric heat capacity was determined. The estimated errors of the data on the enthalpy and the heat capacity were equal to 0.5% and 1.5%, respectively. The results obtained were compared with the available literature data. The position (723 K) of the minimum of the liquid rubidium heat capacity was refined. The tables of the recommended values of the caloric properties within the studied temperature range were developed. [ABSTRACT FROM AUTHOR]

An Erratum to this paper has been published: https://doi.org/10.1134/S0036023622340010 [ABSTRACT FROM AUTHOR]

We will focus on the important aspect of mechanical activation by grinding in a mill, namely, nanoscale wear of the treated substances and of the milling tools. A new technology called abrasive- reactive wear has been developed that utilizes wear debris as an integral component of the reaction system rather than treating it as a harmful impurity. This technology is applied to the processing of low-grade diamond and silicon by cupric milling tools. Abnormal influence of graphite on abrasive wear degree is established. [ABSTRACT FROM AUTHOR]

Thermal conductivity of liquid alloys of the caesium-lead system with a Pb content of 40, 50, 60, and 66.7 at. % is measured by the laser flash method in the temperature range from the liquidus line to 1173 K with an error of 4–6%. It is found that the thermal conductivity of the investigated alloys, obtained by mixing liquid metals Cs and Pb, drops by an order of magnitude to values: 0.5–4.0 W/(m K), characteristic of molten salts. It is shown that the thermal conductivity concentration dependence of the Cs-Pb system liquid alloys has a broad minimum near the equiatomic composition. An analysis of the obtained experimental data indicates the formation of a chemical short-range order in the liquid Cs-Pb system in the vicinity of the equiatomic composition, which indirectly confirms the existing ideas about the presence of Zintl complexes Cs4Pb4 in these melts. [ABSTRACT FROM AUTHOR]