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负荷相反的滴滴的不凝结
W D Ristenpart1, J C Bird, A Belmonte
1Department of Chemical Engineering and Materials Science, University of California at Davis, 1 Shields Drive, Davis, California 95616, USA. wdristenpart@ucdavis.edu
Nature
|September 18, 2009
概括
相反的充电液滴通常会合并. 然而,在临界电场强度以上,这些滴在接触后相互排斥,看起来反弹. 这一发现影响了涉及充电液滴的过程.
科学领域:
- 流体动力学 流体动力学
- 电动运动学 电动运动学
- 体科学是一门关于体的科学.
背景情况:
- 电场驱动各种流体系统的运动,如聚合物和合物悬浮.
- 电气诱导的滴滴运动与喷墨打印,电喷气电离和芯片上的实验室设备有关.
- 邻近的充电滴通常会凝聚在一起,这种现象在许多应用中至关重要.
研究的目的:
- 为了研究电场中相反电荷的液滴的凝聚行为.
- 为了确定凝聚力被抑制的条件.
- 挑战假设相反的电荷滴总是吸引和凝聚的假设.
主要方法:
- 将受控电场应用于对负荷相反的液滴对.
- 使用直接成像观察滴滴相互作用和凝聚.
- 分析阴道桥在滴水之间形成和稳定的情况.
主要成果:
- 相反的电荷滴在电场中向对方迁移.
- 在低电场强度下,滴滴会像预期的那样凝聚在一起.
- 在临界场强度以上,滴在接触时会反击,表现出"反弹"的行为.
- 观察到过渡的半径桥形成,在高电场下发现不稳定.
结论:
- 存在一个临界电场强度,可以防止相反电荷滴的凝聚.
- 观察到的排斥被归因于在强电场下过渡性半径桥的不稳定性.
- 这种现象需要重新评估涉及充电液滴的过程,例如去乳化和电喷离子化.
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