Effect of solutes on single-bubble sonoluminescence in water

Low concentrations of short chain aliphatic alcohols and organic acids and bases suppress single-bubble sonoluminescence (SBSL) in water. The degree o f SL quenching increases with the length of the aliphatic end of the alcoho l, and is related to the concentration of the alcohol at the bubble/water i nterface. The light is preferentially quenched in the shorter wavelength re gion of the spectrum. Radius-time measurements of the bubble are not dramat ically affected by the low levels of alcohol used. Butyric acid and propyla mine behave in the same manner, but only in their neutral forms, indicating that the SBSL suppression is due to processes occurring within the bubble.