在冷/蚀刻盐溶液中的超结构:关于冰的内部清洁
Fredric M Menger1, Ashley L Galloway, Mary E Chlebowski
1Department of Chemistry, Emory University, Atlanta, Georgia 30322, USA. menger@emory.edu
Journal of the American Chemical Society
|May 13, 2004
概括
海冰盐排水的模拟使用了冷蚀刻高分辨率二次电子显微镜. 结的盐水形成了冰冷的围,表明结过程中盐的快速排放.
科学领域:
- 材料科学 材料科学 材料科学
- 地质物理学 地质物理学
- 物理化学 物理化学
背景情况:
- 海冰的形成涉及结的海水,它将缩的盐水困在它的冰矩阵中.
- 随着海冰的增长和变暖,盐水可以通过道向下排放,从而影响冰的特性和海洋盐度.
研究的目的:
- 研究冷盐水溶液中盐水排水的机制.
- 为了可视化盐溶液冷和解过程中的微观结构变化.
主要方法:
- 盐水溶液 (2-3.5%) 被冷或高压冷.
- 使用冷蚀刻高分辨率扫描电子显微镜 (cryo-HRSEM) 来检查冰结构.
- 高真空升华 (蚀刻) 清除了纯冰,揭示了剩余的富含盐的结构.
主要成果:
- 冰冷-HRSEM揭示了围绕以前无形冰的区域的颗粒状冰"围".
- 这些围,大约1-2微米高,幸存蚀刻,表明它们是由冷盐水组成的.
- 这些围的形成意味着结过程中盐的快速排放 (在5-6毫秒内).
结论:
- 这项研究提供了在海冰形成过程中盐的快速排放的证据,通过形成富含盐水的围来可视化.
- 这些发现支持了盐水道形成和在冷盐溶液中的盐迁移模型.
- 观察到的机制突出显示了海冰可以分离盐的速度.
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