Some rules of sonochemistry

Note that a very high-speed stirrer can have effects similar to those of sonication on heterogeneous systems. This may well be a case with the processes induced by hydro-dynamic cavitation rather than acoustic cavitation [28,29]. 

The physical effects of ultrasound in relation to analytical chemistry have not yet been rationalized. 

The two major types of electromechanical transducers are based on the piezoelectric and magnetostrictive effects the former is most commonly used to power bath- and probe-type sonicators. Although more expensive than mechanical transducers, electromechanical transducers are by far the most flexible and widely used. Laser-induced ultrasound is a more recent type of transducer. 

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