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AC Electrokinetic Phenomena Generated by Microelectrode Structures
Published on: July 29, 2008
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由于电场梯度引起的简单流体中的脱混合
Yoav Tsori1, François Tournilhac, Ludwik Leibler
1Laboratoire Matière Molle & Chimie (UMR 167 CNRS-ESPCI), Ecole Supérieure de Physique et Chimie Industrielles, 10 rue Vauquelin, 75231 Paris CEDEX 05, France.
Nature
|July 30, 2004
概括
不均的电场现在可以在实际条件下控制液体混合物相位分离. 这一突破使得可逆脱油,为纳米技术应用打开了大门.
科学领域:
- 物理化学 物理化学
- 材料科学 材料科学 材料科学
- 纳米技术纳米技术
背景情况:
- 液体混合物中的相分离通常由温度和压力控制.
- 像电场这样的外部场可以影响相位分离,但通常需要极端条件,因为合较弱,度波动.
研究的目的:
- 预测和证明不均的电场可以在实际条件下控制液体混合物相位分离.
- 调查电场强度和电极几何形状对脱过程的影响.
主要方法:
- 在不均距离的电极上应用100V电压 (约. 50微米的距离).
- 研究油和油混合物的相分离行为.
- 观察在去除电场梯度后脱的可逆性.
主要成果:
- 不均的电场成功地在相位过渡温度以上1K时诱导了对油和油混合物的可逆脱.
- 效果取决于场强度,电极几何学决定了长度尺度.
- 当移除场梯度时,混合物再次变得均.
结论:
- 不均的电场提供了一种实际的方法来控制液体混合物的相位分离.
- 这种现象在纳米技术中具有潜在的应用,特别是在小型导电物体附近.
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