Abstract
When ultrasonic waves are irradiated to liquid, micro bubbles which called cavitation bubbles are formed. When this bubble collapses adiabatically, the temperature of bubbles instantaneously reaches more than several thousand degrees and several hundred atmospheres. This unique field is expected to be used for decomposition of organic compounds and synthesis of metal nanoparticles. Although the temperature of bubbles is one of the most important parameters to control chemical reactions, the temperature of bubbles formed under air atmosphere has hardly been investigated so far. Therefore, in this study, the temperature of bubbles was estimated under various mixed atmospheres of nitrogen and oxygen. From experiments, the temperature of bubbles was estimated to be lower under nitrogen atmosphere than that under oxygen atmosphere.
