ABSTRACT
Ultrasound spectroscopy is capable of rapid measurements and can be used to characterize systems that are concentrated and optically opaque such as suspensions and emulsions. Ultrasonic spectroscopy utilizes mainly two techniques: a pulse-echo and through-transmission. The theory of ultrasound propagation in dispersions was first considered by Rayleigh. The underlying idea of this theory is that of partial wave analysis. Scattering theory is chosen to avoid the acoustic propagation problem because it is very well suited to the analysis of acoustic propagation in dispersions in the long-wavelength limit. The theory of Harker and Temple can be used when the suspensions contain nonspherical aggregations. There are two major steps in ultrasound analysis. The first step is the measurement of the ultrasonic velocity and/or attenuation spectra and the second step is the interpretation of the resulting spectra using a suitable theory. Ultrasonic spectroscopy can be easily performed in chemistry, physics, biotechnology, pharmaceuticals, agriculture, environmental control and medicine.
