Protonation of norharmane as a sonochemical dosimeter for organic media - The effect of temperature

The sonolysis of different organic and aqueous media in the presence of nor harmane produce its protonation. This simple and reversible reaction is par ticularly suitable as a dosimetric reaction in order to measure the relativ e amount of cavitation induced by the ultrasonic irradiation in non aqueous solutions. The protonation rate increases when small amounts of chloroform are added to the solution. The frequency (20 and 475 kHz) and temperature effects on the reaction rate are also studied. Our results show that sonica tion of aqueous solutions at high frequency leads to a strongly oxidant med ium. (C) 1998 Elsevier Science B.V. All rights reserved.