在反向微粒中激发状态质子转移
Boiko Cohen1, Dan Huppert, Kyril M Solntsev
1Raymond and Beverly Sackler Faculty of Exact Sciences, School of Chemistry, Tel Aviv University, Ramat Aviv 69978, Israel.
Journal of the American Chemical Society
|June 20, 2002
概括
质子扩散在水/AOT逆转的细胞中揭示了细胞结构的洞察力. 该研究发现,微粒水相的介电常数随微粒大小而变化,影响水的特性.
科学领域:
- 物理化学 物理化学
- 超分子化学 超分子化学
- 体科学 体科学 体科学
背景情况:
- 水/AOT逆转小粒是各种化学反应的关键纳米结构.
- 了解水性核心的特性对于控制细胞行为至关重要.
研究的目的:
- 为了研究水中的水性核心的物理化学性质/AOT反向微粒.
- 为了确定微粒大小对介电常数和质子扩散的影响.
主要方法:
- 使用水友光酸 (2-纳夫托尔-6,8-二硫酸) 释放一个自由质子.
- 分析了光衰变信号,使用双联重组算法.
- 计算了放射性质子扩散,考虑到稀释的和静电能.
主要成果:
- 状表面需要原子分辨率建模,硫残留物突出约2 Å.
- 水相表现出与散装水相似的特性,除了介电常数.
- 介电常数因水-微粒接触增加而从较大的微粒 (r(max) ≥16 Å) 的 ~70 降低到较小的微粒的 ~60 .
结论:
- 水性核心的介电常数取决于大小.
- 微粒表面附近的水分子经历了改变的特性.
- 这项研究提供了详细的了解水在逆转细胞系统的行为.
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