Special Features of the Temperature Dependence of the Capillary Constant in the Vicinity of the Critical Point

摘要

The absence of the reliable experimental data in a wide temperature range greatly complicates the development of a method of calculating capillary constant a exp 2 which would yield satisfactory results for various types of materials at various temperatures. For this reason, experimental investigations were carried out into the a exp 2 value of six Freons: 12, 13V1, 115, 142, 143, 152A. The experimental range was 0.3 greater than or equal to epsilon greater than or equal to 10 exp -3 , where epsilon = 1-T/T/sub k/. Measurements were taken using the capillary lift method with five capillaries of various diameter. The experimental results were used to examine the dependence of the derivative dlna exp 2 /dlnepsilon on corrected temperature. In addition to the Freons, the generalized dependence with very small deviations describes the experimental data of other substances, such as liquefied gases Ar, O sub 2 , perfluoroparaffin, n-hexane, benzol, diethyl ester. The associated liquids (water, methanol) are not governed by the generalized dependence and greatly deviate from it. (ERA citation 10:037263)