Surface Tension Measurements for the n-Alcohols in the Temperature Range from −40°C to + 40°C

1983 ◽  
Vol 87 (4) ◽  
pp. 324-327 ◽  
Author(s):  
R. Strey ◽  
T. Schmeling
2012 ◽  
Vol 322 ◽  
pp. 33-39 ◽  
Author(s):  
Sergei Zhevnenko ◽  
Eugene Gershman

High-temperature creep experiments were performed on a Cu-2.8 ат.% Co solid solution. Cylindrical foils of 18 micrometers thickness were used for this purpose. Creep tests were performed in a hydrogen atmosphere in the temperature range of about from 1233 K to 1343 K and at stresses lower than 0.25 MPa. For comparison, a foil of pure copper and Cu-20 at.% Ni solid solution were investigated on high temperature creep. Measurements on the Cu foil showed classical diffusional creep behavior. The activation energy of creep was defined and turned out to be equal 203 kJ/mol, which is close to the activation energy of bulk self-diffusion of copper. There was a significant increase in activation energy for the Cu-20 at.% Ni solid solution. Its activation energy was about 273 kJ/mol. The creep behavior of Cu-Co solid solution was more complicated. There were two stages of diffusional creep at different temperatures. The extremely large activation energy (about 480 kJ/mol) was determined at relatively low temperature and a small activation energy (about 105 kJ/mol) was found at high temperatures. The creep rate of Cu-Co solid solution was lower than that of pure copper at all temperatures. In addition, the free surface tension of Cu-2.8 ат.% Co was measured at different temperatures from 1242 K to 1352 K. The surface tension increases in this temperature range from 1.6 N/m to 1.75 N/m. There were no features on the temperature dependence of the surface tension.


1971 ◽  
Vol 49 (24) ◽  
pp. 3956-3959 ◽  
Author(s):  
Alfred J. Richard ◽  
Kenneth S. Rogers

Isothermal compressibilities of seven organic liquids have been determined by analytical ultracentrifuge techniques, in good agreement with literature values obtained by other methods.A least squares regression equation was derived that correlated the logarithmic values of isothermal compressibilities of 7 organic liquids, determined experimentally, with the liquids' surface tensions. This equation was shown to be valid for 11 other organic liquids (values obtained from literature) over a temperature range of 0° through 50°, and a surface tension range of 13 to 44 dyn per cm.


2021 ◽  
Author(s):  
Amin Alibakhshi ◽  
Bernd Hartke

Temperature dependence of vaporization enthalpy is one of the most important thermophysical properties of compounds. In the present study, we theoretically developed relationships applicable to evaluation of vaporization enthalpy of compounds from diverse chemical families for a wide temperature range from melting point to the critical temperature. One outcome of the proposed approach is a relationship describing the correlation between the surface tension and vaporization enthalpy which outperforms the extensively applied Kabo method proposed for the same purpose.<br>


2019 ◽  
Vol 55 (1) ◽  
pp. 40-46
Author(s):  
O. Ya. Khliyeva ◽  
D. A. Ivchenko ◽  
K. Yu. Khanchych ◽  
I. V. Motovoy ◽  
V. P. Zhelezny

Information on surface tension is necessary for modeling boiling processes in nanofluids. It was shown that the problem of predicting the surface tension of complex thermodynamic systems, such as nanofluids, remains outstanding. It should be noted that the surface tension of liquids and the saturated vapor pressure are due to a specific intermolecular interaction in the region of spatial heterogeneity of the substance (surface layer). Moreover, the compositions of the surface layer of nanofluid and its liquid phase are not equal. The presence of nanoparticles in the base fluid affects the composition of the surface layer of liquids. However, there are no methods for determining the composition of the surface layer of nanofluids and this fact complicates establishing the dependence of the surface tension on the state parameters of nanofluids. It should be mentioned that the number of possible methodological errors in measurements of the saturated vapor pressure of nanofluids is significantly lower than for the surface tension measurements. Therefore, in the development of models for predicting the surface tension, scientific and practical interest has establishing the relationship between the surface tension and the saturated vapor pressure of nanofluids. In the presented work, we consider the nanofluids of isopropanol/Al2O3 nanoparticles and o-xylene/fullerenes C60. Saturated vapor pressure and surface tension of nanofluids of isopropanol/Al2O3 nanoparticles have been studied in the temperature range 293 – 363 K and concentrations of Al2O3 nanoparticles 0-8.71 g/kg. Measurement of saturated vapor pressure and surface tension of nanofluids of o-xylene/fullerenes C60 have been performed in the temperature range 283 – 348 K and the concentration of C60 0-7.5 g/kg. It is shown that additives of Al2O3  nanoparticles and fullerenes C60 lead to a decrease in the surface tension and increase in the saturated vapor pressure. It is shown that there is a universal dependence between the reduced surface tension and saturated vapor pressure for the researched nanofluids.


1985 ◽  
Vol 63 (5) ◽  
pp. 1132-1138 ◽  
Author(s):  
T. Fujisawa ◽  
T. Utigard ◽  
J. M. Toguri

The maximum bubble pressure method was used to determine the surface tension and density of melts within the PbCl2–KCl–NaCl system. The temperature range of this study was from 450 to 800 °C. In all cases, the surface tension was found to decrease with increasing temperature. At constant molar ratios of KCl to NaCl, a minimum in the surface tension was observed at approximately 40 mol% PbCl2. The ternary surface tension values were found to obey the simple additivity expression of the binary surface tensions of PbCl2–KCl and PbCl2–NaCl. Based on these findings, constant surface tension contours have been drawn.The density obtained in the present study agree well with the previously determined densities using a bottom-balance Archimedean technique reported by this laboratory.


Author(s):  
Sugumar Dharmalingam ◽  
Kek Kiong Tio

In order to elucidate the effects of working fluid’s properties on the heat transport capacity of a micro heat pipe, 3 commonly used fluids are selected for this study: water, ammonia and methanol. From the results obtained, it shows that for operating temperatures lower than 50°C, ammonia is preferred, but if the operating temperature exceeds 50°C, water is more suitable in transferring heat. Over the temperature range of 20°C∼100°C, the behavior of the heat transport capacity is found to be dominated by a property which is the ratio of the working fluid’s surface tension and liquid viscosity. This property which has the dimension of velocity has a controlling effect on the working fluid’s rate of circulation and therefore, the heat transport capacity.


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