Low-frequency (105 Hz) shear modulus of nanosuspension

The low-frequency shear wave propagation in a suspension of silica nanoparticles in a polyethylsiloxane liquid was studied. The shear wave length was measured on ultrasonic interferometer, and it is equal to 55 μm. The value of the tangent of the mechanical losses angle is determined to be 0.18. These parameters were used to calculate the shear modulus of the investigated colloidal suspension; its value is 0.15‒105 Pa. The results obtained are in quite agreement with the data obtained by another way of the acoustic resonance method.

Density and speed of sound in refrigerant vapor R-125 (31 wt. %) + R-134A (69 wt. %)

Using a constant volume piezometer and ultrasonic interferometer methods, the density and speed of sound in gaseous mixture R-125 (31 wt. %) + R-134a (69 wt. %) were measured within the temperature range from 293 to 393 K and at pressure from 0.18…0.47 to 2.5 MPa. The errors in the measuring temperature, pressure, density and speed of sound were ±20 mK, ±4 kPa, ± (0.15–0.3) %, ± (0.1–0.2) %, respectively. It was shown that the speed of sound values increase with temperature and decrease with pressure. The obtained results were compared with the calculations using the REFPROP software.

Ultrasonic Parameters of Some Ternary Liquid Mixture

At different composition and frequeny ultrasonic velocity has been measured in some ternary liquid mixtures at room temperature with the help of ultrasonic interferometer. Composition and frequency dependent variation of relaxation time (τ) have been shown in Figs. And analyzed for these ternary liquid mixtures.

Density, Viscosity and Ultrasonic Velocity of Polyethylene Glycol

Ultrasonic velocity, density, and viscosity of polyethylene glycol have been measured for the solution in water at concentration range of 0.3% to 1% at temperature 50oC. Ultrasonic velocity has been measured using ultrasonic interferometer at 1MHz frequency. By using the values of ultrasonic velocity, density, and viscosity, various acoustical parameters like adiabatic compressibility, acoustic impedance, intermolecular free length, and relaxation time have been calculated. The change in these acoustical parameters is explained in terms of solutesolvent interaction in a polymer solution.

Ultrasonic Velocity & other Related Parameters

Ultrasonic velocity is an important parameter, characterizing the state of the system. It can be determined experimentally by using Ultrasonic Interferometer. A brief discussion of ultrasonic interferometer and mode of determining ultrasonic velocities is given. The present paper deals with the experimental determination of ultrasonic velocities and adiabatic compressibility’s of ethylene glycols and higher homologous. From the ultrasonic velocity, closely related parameters like molar sound velocity, molar compressibility, and Vander Waal’s constant ….etc. are evaluated. The variations in ultrasonic velocity and related parameters with degree of polymerization and a phenomenal reasoning for the same are also permuted. key words: Ultrasonic velocity, Adiabatic Compressibility, Molar sound velocity, Molar compressibility, Vander Waal’s Constant and Inter Molecular Free length