Chemical and Luminescent Aspects of Single-Bubble Sonoluminescence : Control and Observation

单气泡声致发光是指单个或少数气泡在声驻波作用下发出脉冲发光的现象。自十年前发现这一现象以来，许多研究人员对其进行了深入的研究，部分原因是气泡在空间和时间上是静止的。本研究的目的是利用SBSL探索与空化相关的“发光-流体动力学-化学反应”的交叉学科领域，以下四位研究人员参与了该项目：S.Hayashi在获得专有技术的同时测量了气泡的性质。T.Kamakura从理论和实验上研究了声辐射。T.宫崎做了一个理论上的。研究影响气泡动力学的涡流。K.Yasui提出了一个详细的理论模型，其中许多分子和自由基物种解离和电离，并将其应用于以下问题：表面活性剂如何影响SBSL？ 关于我们 动力学，是什么使氢SBSL最突出，如何单泡和多泡声致发光的区别，等等。至于SBSL实验，我们首先集中在实验技术的发展，为创建气泡和测量的性质。各种声学谐振器和换能器进行了测试。然后，我们采用了米氏散射技术来研究气泡动力学，但遇到了一些困难，如低信噪比和大的背景信号。在理论建模的帮助下，这些问题得到了解决。我们还使用视频显微镜和针型水听器进行了测量，视频显微镜在电解辅助SBSL中非常有用，其中在电极上产生种子气泡。我们观察了在电解过程中气泡如何在电极上生长，小颗粒如何从电极上离开，以及气泡如何通过超声波在电极上凝结。因此，我们已经取得了探索新的跨学科领域所需的基本理解。少

The single-bubble sonoluminescence(SBSL)is a phenomenon in which a single or a few bubbles that are trapped in the acoustic standing waves emit pulsed luminescence. The phenomenon has been investigated intensively by many researchers since it was discovered ten years ago, partly because the bubble is stationary in space and time. the purpose of the present research is to explore the interdisciplinary field of "luminescence-fluid dynamics-chemical reactions" associated with cavitaton by exploiting SBSL.The following four researchers participated in the project : S.Hayashi measured the properties of bubbles while obtaining the know-how. T.Kamakura investigated acoustical radiation theoretically and experimentally. T.Miyazaki did a theoretical. research on vortices, which affect the bubble dynamics. K.Yasui proposed a detailed theoretical model in which many molecular and radical species dissociated and ionized, and applied it to the following problems : how surfactants affect the SBSL dy … More namics, what makes hydrogen SBSL most outstanding, how single-bubble and multibubble sonoluminescence differ, etc.As for the SBSL experiment, we first focused on the development of experimental techniques for creating bubbles and measuring the properties. Various acoustical resonators and transducers were tested. We then adopted a Mie-scattering technique to investigate the bubble dynamics, but met some difficulties such as low S/N and large background signals. With the help of theoretical modelling, these problems have been resolved. We also did measurements using video microscope and needle-type hydrophones.Video microscopy was very useful in electrolys-assisted SBSL in which seeding bubbles were created on the electrodes. We observed how the bubbles grow on the electrode during electrolysis, how small particles leave from it, and how the bubbles coagulate on the electrode by ultrasounds. Thus, we have achieved a basic understanding required for exploring the new interdisciplinary field. Less