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Updated: May 21, 2025

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Measuring the Densities of Aqueous Glasses at Cryogenic Temperatures
Published on: June 28, 2017
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在接近玻璃过渡温度的温度下超冷液体水的扩散性
R Scott Smith1, Wyatt A Thornley1, Greg A Kimmel1
1Physical Sciences Division, Pacific Northwest National Laboratory, PO Box 999, Mail Stop J7-10, Richland, Washington 99352, United States.
The journal of physical chemistry letters
|March 20, 2025
概括
研究人员使用同位素分层膜测量了超冷水的扩散. 结果显示,在玻璃过渡附近存在类似液体的运动,在玻璃过渡上方支持连续的液态状态.
科学领域:
- 物理化学 物理化学
- 材料科学 材料科学 材料科学
- 热力学是一种热力学.
背景情况:
- 对于各种科学领域来说,了解水在玻璃过渡期附近的行为至关重要.
- 无形固体水表现出尚未完全理解的复杂性质,特别是其过渡到液态.
研究的目的:
- 测量深度超冷液体水的转化扩散率.
- 研究无形水在其玻璃过渡温度以上的液态状态的性质.
主要方法:
- 制备同位素分层无形固体水膜 (H2 ^ 18O和H2 ^ 16O).
- 以非常缓慢的速度 (低至10^-4K/s) 进行受控加热,以分离扩散和结晶.
- 混合的分析,使用吸光谱的数值模拟来提取扩散性.
主要成果:
- 获得的转化扩散率与类似液体的运动一致.
- 在接近和高于136K的拟议玻璃过渡温度 (Tg) 的温度下观察到这种运动.
- 扩散测量是在结晶开始温度以下进行的.
结论:
- 这些发现支持这样一个假设,即无形水的融化与正常超冷液态水的热力学连续性.
- 类似于液体的转换运动在接近其玻璃过渡的无形水中持续存在.
- 这项研究提供了关键的实验数据水的行为在一个深超冷的政权.
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