Technique for Measuring the Adiabatic Compressibility, Density, and Sound Speed of Sub-microliter Liquid Samples.
Abstract:
An acoustical technique for measuring a known function of the adiabatic compressibility and density of a very small liquid sample 0.000004 - 0.004 ml has been developed. The technique involves a comparison of the conditions required for the acoustic levitation of the sample at a given position in a known, immiscible host liquid and the levitation of a reference droplet of known properties at the same position. It was decided to test the validity of the procedure by using liquids of known properties so that a comparison with our results would be possible. Two particularly attractive features of the procedure are 1 the results are independent of droplet size, and 2 the parameters of the sound field need not be known. This technique should be directly applicable to measurements of properties of superheated and supercooled liquids.