Various methods for broad-band ultrasonic absorption and velocity measurements in liquids, using CW and pulsed signals, are reviewed. Several different ultrasonic spectrometric techniques are required to cover the wide range of liquid wavelength and attenuation values that exist in the kilohertz to gigahertz frequency range. Advantages and problems of various ultrasonic and related methods are discussed. Sonic cells for liquids and electronic equipment for spectral measurements are presented. Together with applications in relaxation spectrometry, examples of broad-band ultrasonic absorption spectra, utilizing different CW resonator and pulse-modulated travelling wave techniques, are presented.

https://iopscience.iop.org/article/10.1088/0957-0233/7/1/001/pdf

Broad-band ultrasonic measurement techniques for liquids

This review gives a short introduction into the principles of sound velocity measurements. The fundamentals of acoustical methods using continuous waves, pulse modulated signals and sharp pulses are summarized. Methods employing optical wave interactions with continuous ultrasonic waves are also described briefly. Recent advances in the different methods are presented, and the technical status of the currently preferred techniques is discussed in view of their merits and limitations, too. Particular emphasis is given to the sensitivity and accuracy of the methods. Selected examples of measurement applications indicate the extended usability spectrum in basic research as well as in materials' characterization, manufacturing processes and control routines.

https://iopscience.iop.org/article/10.1088/0957-0233/19/6/062001/pdf

Ultrasonic velocity measurements in liquids with high resolution—techniques, selected applications and perspectives

Between 100 kHz and 2 GHz ultrasonic absorption spectra have been measured for aqueous solutions of d-galactose, d-mannose, d-glucose, d-arabinose, d-ribose, d-lyxose, and d-xylose, as well as of t...

Molecular Dynamics and Kinetics of Monosaccharides in Solution. A Broadband Ultrasonic Relaxation Study

At 25 °C the ultrasonic absorption spectra between 100 kHz and 2 GHz, the sound velocities, and the shear viscosities of aqueous solutions of n-heptylammonium chloride have been measured at the cri...

On the Kinetics of the Formation of Small Micelles. 1. Broadband Ultrasonic Absorption Spectrometry

Molecular relaxation properties of the monosaccharides (a) D-glucose, (b) methyl {beta}-D-glucopyranoside, (c) methyl {alpha}-D-mannopyranoside, (d) D-xylose, (e) D-arabinose, (f) methyl {beta}-D-xylopyranoside, (g) methyl {beta}-D-arabinopyranoside, (h) methyl {alpha}-L-(6-deoxy)mannopyranoside, and (i) 1,6-anhydro-{beta}-D-glucopyranoside, all in aqueous solution, have been studied using broad band ultrasonic spectrometry in the frequency range 0.2-2000 MHz. Ultrasonic excess absorption with relaxation characteristics near 80 MHz was found for glucose and the methyl glucosides of D-glucose and D-mannose, but no relaxation process was detected for the other monosaccharides in the same frequency range. From structural aspects it is deduced that the most likely process causing the observed relaxation is the rotation of the exocyclic -CH{sub 2}OH group, placing rotational isomerization on the nanosecond time scale. Relaxation parameters for D-glucose and methyl {beta}-D-glucopyranoside solutions were further investigated as a function of concentration and temperature, in order to confirm the assignment of the relaxation process, and to determine some of its thermodynamic and kinetic parameters. 19 refs., 7 figs., 1 tab.

V. Kühnel

Papers

Variable pathlength cells for precise hypersonic spectrometry of liquids up to 5 GHz