限制还是界面的性质? 纳米水的动力学
David E Moilanen1, Nancy E Levinger, D B Spry
1Department of Chemistry, Stanford University, Palo Alto, California 94305, USA.
Journal of the American Chemical Society
|October 26, 2007
概括
反向微粒中的水动力学取决于封闭,而不是表面活性剂类型. 超快的红外光谱学揭示了类似的键重排在纳米水池,无论离子或非离子的头组.
科学领域:
- 物理化学 物理化学
- 纳米技术纳米技术
- 频谱学是一种光谱学.
背景情况:
- 当水局限于纳米环境时,其独特的特性会发生显著的变化.
- 反向微粒为研究纳米水的模型系统提供了一个模型系统,具有不同的界面特性.
研究的目的:
- 调查表面活性剂头组身份对类似尺寸的纳米水池中的水动态的影响.
- 区分界面特性与简单的限制对水行为的影响.
主要方法:
- 超快的红外 (IR) 探波光谱被用来研究HOD在H2O中的基 (OD) 延伸.
- 制备了两种类型的反向微粒:Aerosol-OT (离子) 和Igepal CO 520 (非离子),具有相同的水纳米极直径.
主要成果:
- 虽然表面活性剂头组影响了当地的水环境,但振动寿命显示出明显的变化.
- 导向动态,反映了键网络的重新排列,在两种小细胞类型之间非常相似.
- 这表明纳米限制是决定水的动态的一个主要因素.
结论:
- 这些纳米系统中水动态的主要决定因素是接口所施加的限制效应.
- 表面活性剂头组 (离子与非离子) 的特定化学性质在类似大小的纳米聚合物中的水动力学中起到次要作用.
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