水氧化有机表面的冰核效率由它们的结构波动和与冰的不匹配控制
Yuqing Qiu1, Nathan Odendahl1, Arpa Hudait1
1Department of Chemistry, The University of Utah , 315 South 1400 East, Salt Lake City, Utah 84112-0850, United States.
Journal of the American Chemical Society
|January 31, 2017
概括
有机表面影响冰核形成. 模拟和实验表明表面结构和波动, 不仅仅是格子匹配, 决定冰的形成温度, 影响气候和工业.
科学领域:
- 物理化学
- 材料科学
- 大气科学
背景情况:
- 有机物质的异质冰核对气候,生物学和工业至关重要.
- 长链酒精单层是有效的冰核,与脂肪酸单层不同.
- 表面格子与冰相匹配以前被认为可以控制冰核的效率.
研究的目的:
- 研究有机表面结构,波动和冰核温度之间的关系.
- 了解为什么酒精单层是比脂肪酸单层更有效的冰核.
- 开发一个将表面热力学与冰核结合的框架.
主要方法:
- 分子动态模拟
- 实验室实验
- 古典核化理论
主要成果:
- 水氧化有机表面将界面水排列成类似冰的域,从而启动冰的形成.
- 格子不匹配和表面波动都减少了预先订定的域大小,降低了结温度.
- 与格子不匹配相比,酒精和酸单层的结效率减半.
结论:
- 表面结构和波动,以及格子不匹配,是冰核效率的关键决定因素.
- 由于调节的结构不匹配,酒精的冷效率高于酸.
- 冰将自由能量结合到表面可以预测冰核的结温度.
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