THE EFFECT OF BULK SOLUTION TEMPERATURE ON THE INTENSITY AND SPECTRA OF WATER SONOLUMINESCENCE

The sonoluminescence spectra of argon-saturated water were studied in the 210-500 nm wavelength region at 1.1 MHz, 337 kHz and 22 kHz ultrasound frequencies in the 11 degrees C-70 degrees C temperature interval. The intensity of the light emission decreased with an increase in temperature, but the temperature dependencies were different for high and low frequencies. The total light power of sonoluminescence was compared with the formation rate of hydrogen peroxide. The results allowed the calculation of the ratio of photons, emitted by the excited hydroxyl radicals, to the total number of hydroxyl radicals formed. The value of OH*/OH was equal to similar or equal to 1.0, 1 and 5.5 x 10(-3) for 1.1 MHz, 337 kHz and 22 kHz respectively. The short-wave part of the spectra decreased with the growth of ambient temperature and with the decrease of ultrasound frequency. The proposed interpretation includes an argument on the essential role of water molecules in the processes of luminescence quenching.