Sonochemistry and sonoluminescence

Fig. 1. Transient acoustic cavitation the origin of sonochemistry and sonoluminescence.

The phenomenon of acoustic cavitation results in an enormous concentration of energy. If one considers the energy density in an acoustic field that produces cavitation and that in the coUapsed cavitation bubble, there is an amplification factor of over eleven orders of magnitude. The enormous local temperatures and pressures so created result in phenomena such as sonochemistry and sonoluminescence and provide a unique means for fundamental studies of chemistry and physics under extreme conditions. A diverse set of apphcations of ultrasound to enhancing chemical reactivity has been explored, with important apphcations in mixed-phase synthesis, materials chemistry, and biomedical uses. 

Sostaric JZ (1999) Interfacial effects on aqueous sonochemistry and sonoluminescence. PhD thesis, University of Melbourne, Australia... 

Suslick KS, Crum LA (1977) Sonochemistry and sonoluminescence, Encyclopedia of Acoustics. Wiley, New York, pp 271-282... 

Abstract Having discussed many aspects of sonochemistry and its application in the previous chapters, a few introductory experiments in sonochemistry and sonoluminescence are presented in this chapter. These physical demonstrations are especially aimed at beginners in the field of sonochemistry making them e.g. aware of the power of ultrasound. 

Following are some of the introductory experiments in sonochemistry and sonoluminescence. 

The book offers a theoretical introduction in the first three chapters, provides recent applications in material science in the next four chapters, describes the effects of ultrasound in aqueous solutions in the following five chapters and finally discusses the most exciting phenomenon of sonoluminescence in aqueous solutions containing inorganic materials in subsequent two chapters, before ending with a few basic introductory experiments of sonochemistry and sonoluminescence in the concluding chapter. 

The idea of writing a book on inorganic sonochemistry originated way back in 2000 but turned to reality only recently when discussed with Dr. Sonia Ojo from Springer UK. She thankfully introduced me to Prof. Muthupandian Ashokkumar, University of Melbourne, Australia, a very well known name in the area of sonochemistry and sonoluminescence, to accomplish the task. Furthermore, I would also like to acknowledge Mrs. Claudia Culierat from Springer UK for her instantaneous and supportive attention to all my queries related to editorial assistance. 

L.A. Crum, T.J. Mason, J.L. Reisse, and K.S. Suslick (eds.), Industrial applications of sonochemistry and power ultrasonics, Sonochemistry and Sonoluminescence, NATO ASI Series, Kluwer Academic Publishers, 1999, 377-390, ISBN 0-7923-5549-0. 

J. Reisse, C. Caulier, Y. Dekerckheer Kegelaers, N. Segebarth, and K. Bartik, Sonochemistry and Sonoluminescence,... 

The chemical effects of ultrasound do not arise from a direct interaction with molecular species. Ultrasound spans the frequencies of roughly 15 kHz to 1 GHz. With sound velocities in liquids typically about 1500 m/s, acoustic wavelengths range from roughly 10 to 10 4 cm. These are not molecular dimensions. Consequently, no direct coupling of the acoustic field with chemical species on a molecular level can account for sonochemistry or sonoluminescence. Instead, sonochemistry and sonoluminescence derive principally from acoustic cavitation, which serves as an effective means of concentrating the diffuse energy of sound. 

Crum, L. A., J L. Rdsse, and K. S. Suslick Sonochemistry and Sonoluminescence, Kluwer Academic Publishers. Noiwell, MA, 1998. 

Colussi AJ, Hoffmann MR. Vapor supersaturation in collapsing bubbles. Relevance to the mechanisms of sonochemistry and sonoluminescence. J Phys Chem A 1999 103 11336-11339. 

The generally accepted explanation for the origin of sonochemistry and sonoluminescence is the hot-spot theory, in which the potential energy given to the bubble as it expands to maximum size is concentrated into a heated gas core as the bubble implodes. The oscillations of a gas bubble driven by an acoustic field are well described by the Rayleigh-Plesset equation.7... 

Flannigan DJ, Hopkins SD, SusUck KS (2005) Sonochemistry and sonoluminescence in ionic Uquids, molten salts, and concentrated electrolyte solutions. J Organomet Chem 690 3513-3517... 

---