1971 年 27 巻 10 号 p. 524-530
The ultrasonic velocities of methyl, ethyl, n-propyl, and n-butyl acetate were measured with high-pressure type ultrasonic interferometer at a frequency of 4 MHz. The measured pressure was up to 300 atm. , and the temperature range was from 5℃ to 35℃. The ultrasonic velocities of these esters increased with the increase of pressure parabolically, as shown in Fig. 3 to Fig. 5 and decreased with the temperature rise linearly as shown in Fig. 6. From these results, the non-linearity parameters, B/A, were determined. These values were summarized in Table 1. As in seen in Table 1, nonlinearity parameters were almost completely due to the pressure dependence of sound velocity and independent of the temperature. On the basis of the oscillator-model of liquid, the following equation was derived;1/C(∂C/∂P)/β_T=(n+m+3)/6From this equation, the indexes of Mie's potential, n+m, were determined from the data of the pressure dependence of the sound velocity and iso-thermal compressibility. These values were summarized in Table 3, which were in good agreement with the data obtained by Moelwyn-Hughes by the static method.