裂微气泡的动力学,导致闪的工件
Eric Rokni1, Eusila C Kitur1, Julianna C Simon1
1Graduate Program in Acoustics, The Pennsylvania State University, University Park, PA 16802, USA.
Ultrasonics sonochemistry
|June 28, 2024
概括
多普勒超声波闪的工件是由裂中的微泡引起的. 较小的裂 (1-10微米) 在较低的频率产生更多的闪,而更大的裂 (100微米) 在更高的频率占主导地位.
科学领域:
- 超声波物理学的超声波物理
- 生物医学工程 生物医学工程
- 材料科学 是一种材料科学.
背景情况:
- 多普勒超声波闪的工件,一种快速的颜色变化,在病理性矿化中观察到.
- 理论上,这个文物是由微米大小的裂微气泡分散而产生的.
- 裂特征和泡动态对闪的确切影响仍然不清楚.
研究的目的:
- 为了研究裂尺寸,泡动力学和多普勒超声波闪文物之间的关系.
- 阐明病理性矿化中闪文物生成背后的机制.
主要方法:
- 制造精确蚀刻圆柱形裂的片 (直径为0.8-100微米,深度为1-10微米).
- 使用多普勒模式的研究超声波系统在各种频率 (0.75-18.5 MHz) 上进行实验成像.
- 高速摄影用于监测裂内的泡动态.
- 实验结果与衍生的裂泡模型进行比较.
主要成果:
- 在研究的压力范围 (∼1 MPa) 内,没有观察到0.8-1.2μm裂泡的泡振荡,与计算模型一致.
- 直径为1和10微米的裂在5和7.8 MHz时产生了比100微米裂更多的闪.
- 相反,100微米裂在18.5 MHz时产生了比1或10微米裂更明显的闪 (p < 0.001).
结论:
- 裂的大小和超声波频率显著影响多普勒超声波闪的强度.
- 这些发现提供了对病态矿物化的闪文物形成的关键见解,有助于诊断解释.
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