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The proposed relations describe the pressure of saturated and superheated vapor of simple and nonpolar substances. It is shown that the noncovalent, long-range, chemical bonding forces—the Mendeleev forces—make the dominant contribution to the energy of interaction of vapor particles. The binding energy is proportional to the critical temperature of the substance. [ABSTRACT FROM AUTHOR]

The paper presents the results of experimental studies of the arc discharge between the graphite electrodes in an argon atmosphere at a pressure of 0.1–100 kPa. The discharge was ignited after the destruction of a graphite bar heated by a fixed electric current and maintained for ~103 s at a temperature of ~3 kK. Evidence of the formation of liquid phase on the surface of the graphite electrodes at a temperature of ~3.2 kK is presented. Data on the saturated carbon vapor pressure are discussed. The pressure in the carbon triple point does not exceed ~0.1 kPa. [ABSTRACT FROM AUTHOR]

A model is proposed for intensification of the process of high-temperature vacuum removal of iron impurities from microporous aluminum oxide via purging of the particle layer with argon. In the temperature range characteristic of this process, the pressure of saturating vapors above pure iron is on the order of 0.1 mm Hg. For an impurity with a concentration of several particles per million, the figure is proportionally smaller, and this creates problems with evacuation of the chamber. The use of argon as a carrier gas destroys the rigid connection between the partial vapor pressure of the impurity and the pressure in the vacuum chamber. Calculations show that the argon flow under moderate vacuum 10–5 mm Hg with a mass flow rate on the order of 10–7 kg/(m2 s) provides a very deep purification. [ABSTRACT FROM AUTHOR]

We present the results of investigation of a discharge with a current of 15-200 A between graphite electrodes at argon pressure of 10-90 kPa after long-term specimen heating by the DC at a temperature of about 3 kK. The change in the electrode shape is evidence of the existence of a melt film on the electrode surfaces at the temperature of 3.3-3.5 kK. The anode vaporization velocity is in agreement with the data on the pressure of the saturated vapor of the atomic carbon. [ABSTRACT FROM AUTHOR]

The quantitative relationship of pressure (activity a) of alkali metals M and the work function φ of the effusion chamber inner surface, φ = φ(M) − kTln a( M), is studied. The experimental data on the pressure values of ions proved that the equation can be applied in practice. [ABSTRACT FROM AUTHOR]

By the example of ion-molecular reactions in fluoride systems, including alkali metals, we show the influence of the effusion chamber material and of the inserted addition agents on formation of the ion emitting surface. In the mass-spectrometric experiment, the possibility of polarization of this surface upon ion current takeoff is estimated. [ABSTRACT FROM AUTHOR]

The results of studies of surface tension of metal melts with addition of alkali metals, mainly as small additives, are discussed. It is shown that small additives of alkali metals exhibit a high surface activity. The extrema that are observed on the surface tension isotherms of a number of binary systems are built using very few experimental points; hence, their authenticity seems unreliable. The main disadvantages of the methods and the measuring cells used to define the surface tension, etc., which may violate the conditions of thermodynamic equilibrium of the surfaces under study with their saturated vapor, are discussed. In the authors' opinion, a number of experimental and theoretical problems remain unsolved in the field of the temperature and concentration dependences of the surface tension of alloys with small additions of alkali metals. [ABSTRACT FROM AUTHOR]

The measurements results of the sound speed, density, and isobaric heat capacity of liquid squalane on the saturation line and at atmospheric pressure within the temperature range of 263.15-413.15 K are presented. The data obtained are used to calculate the ratio of the heat capacities, γ; adiabatic, β, and isothermal, β, compressibilities; thermal expansion coefficient, α, thermal pressure coefficient, $$\left( {\frac{{\partial P}} {{\partial T}}} \right)_V $$ and also to estimate the energy of the intermolecular interaction on the basis of the discrete-continuum model. [ABSTRACT FROM AUTHOR]

An analytical dependence between the critical temperature of the model system and the minimum of the interaction potential is obtained. It is shown that the law of corresponding states is fulfilled in the system with a three-parameter pair interaction potential, and the obtained thermodynamic properties of the system do not depend directly on the parameters of the potential, being the functions of a dimensionless combination of these parameters. Several thermodynamic properties of cesium vapor are calculated on the line of saturation and in a single-phase region. The results of the calculation are compared with the experimental data. [ABSTRACT FROM AUTHOR]

The data of video filming of the behavior of air bubbles near the heating surface during boiling of subcooled water are presented. The effects the regime parameters (heat flow rate and water subcooling relative to the saturation temperature) have on the characteristics of the vapor-air-water mixture are described. [ABSTRACT FROM AUTHOR]

The stability is investigated (linear and nonlinear analysis) of the interface between a thin vapor film and a layer of liquid in the presence of a steady heat flux from a metal surface heated to a high temperature to the vapor film and then from vapor to subcooled liquid. In view of thermal disequilibrium which takes into account the temperature dependence of saturation pressure, boundary conditions on the vapor-liquid interface are derived, which generalize the known correlations on the free surface of liquid in the gravity field. A number of new effects arise in the problem under consideration, as distinct from the classical problem. The thermal processes, which occur on the phase boundary and are possible in the absence of the force of gravity as well, lead to the generation of weakly decaying periodic waves of low amplitude, whose velocity may exceed significantly that of gravity waves. The heat flux through the interface may cause on this surface periodic waves of small length (ripple) which are not capillary. The processes of phase transition on the interface are capable of providing for the stability of vapor film under the layer of liquid in the gravity field. Along with periodic waves and solitons, the mode of explosive instability may arise in the nonlinear stage because of a weak variation of the film thickness, where the amplitude of an initially low-amplitude plane wave rises to infinity during a finite period of time. [ABSTRACT FROM AUTHOR]

The activity coefficients of the components of a Na–K–Cs ternary system in a temperature range of 773–1200 K are determined using the previously calculated thermodynamic properties, in particular, the activity of the components of binary alloys of alkali metals such as Na–K, Na-Cs, and K–Cs, at high temperatures [1–3]. The sides of the triangle of the phase diagram of this system are constituted by the binary Na–K, Na–Cs, and K–Cs binary alloys. The results obtained are used to calculate the saturated vapor pressure of the sodium–potassium-cesium eutectic (22.1 wt % K and 73.8 wt % Cs [4, 5]) in the same temperature range. The calculated data are in good agreement with the recommended reference data [6]. [ABSTRACT FROM AUTHOR]

The results are given of the investigation of the processes of plastic strain of VT20 titanium alloy under the effect of high-density current pulses without heating the surface of specimens at temperatures below that of intense gas saturation. The current density in a specimen is changed by variation in the charging voltage of capacitors, and the duration of pulses, by varying their capacitance. In the experiments, the processes of changing strain, load, current, and the surface temperature of the specimens are registered. The experimental results are discussed, and the data obtained are mathematically processed. [ABSTRACT FROM AUTHOR]

The method of molecular dynamics is used to investigate the p, ρ, T-properties and the structural characteristics of the Lennard–Jones fluid in the stable and metastable states in the liquid–gas phase transition. The calculation results demonstrate the presence of phase separation in molecular models at close-to-spinodal supersaturation. The effect of the cut-off radius of the interparticle potential on the process of phase transformation is analyzed, and the position of spinodal of superheated liquid and supersaturated vapor is estimated. [ABSTRACT FROM AUTHOR]

The article focuses on the thermal expansion coefficients (TECs) of saturated liquids. It says that TEC along the saturation line of the liquid is small because the slope of the isobars close to the saturation line. It adds that the ratios of the liquids such as water, mercury and argon vary within the narrow range for it to be taken as the similarity parameter. Moreover, an example of application of high-temperature data on the liquid lead TEC must be consider to estimate its temperature.

The article focuses on the use of alkali metal halides (AMH) as coolants in high-power energy facilities. It is stated that AMH exhibit a lower vapor tension, due to which liquid AMH can be used more effectively in heat pipes at higher temperature as compared to alkali metals. It is mentioned that clusters of thermodynamically stable phase are formed in the case of vapor-liquid first-order transition under supercooling.

Discusses the thermomechanical action of the fine fragmentation of liquid droplets subjected to vapor explosion. Fine fragmentation of melt into small particles with the surface of melt-liquid interaction increasing by orders of magnitude; Transition of nucleate boiling which implies that a mass of cool liquid comes in direct contact with a hot surface; Basic equations of internal pressure.