研究声气泡的凝聚作为频率,功率和水溶性添加剂的函数
Devi Sunartio1, Muthupandian Ashokkumar, Franz Grieser
1Particulate Fluids Processing Centre, School of Chemistry, University of Melbourne, Melbourne, Victoria 3010, Australia.
Journal of the American Chemical Society
|April 19, 2007
概括
像二甲硫酸盐 (SDS) 这样的表面活性溶液减少了超声波处理期间的泡凝聚. 气泡的寿命是有限的,并且随着超声波频率的增加而减少,SDS无法达到平衡吸附.
科学领域:
- 物理化学 物理化学
- 合体和表面科学科学
- 声学 声学 在声学上
背景情况:
- 表面活性溶液影响液体中的泡行为.
- 超声波引入声学能量,影响泡动态.
研究的目的:
- 研究表面活性溶液在超声波下对气泡凝聚的影响.
- 确定声力和频率对气泡凝聚和寿命的影响.
主要方法:
- 在超声波后测量溶液体积变化,以量化泡凝聚.
- 在不同的声学条件下研究亚利法醇和二甲基硫酸盐 (SDS).
主要成果:
- 表面活性溶液的吸附通常会延缓泡凝聚.
- 气泡凝聚没有显示对声功率的依赖.
- 当短距离排斥占主导地位时,观察到频率依赖,更高的频率降低了凝聚抑制.
- 在泡/溶液界面上,SDS没有达到平衡吸附.
结论:
- 提出了一种方法来估计不平衡表面的超值值.
- 在多气泡场中的气泡寿命是有限的,并且随着声频的增加而减少.
- 估计的泡寿命范围从0.35毫秒 (213千赫) 到0.10毫秒 (1062千赫).
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