相关实验视频
Updated: Jul 12, 2025

09:50
Measuring the Densities of Aqueous Glasses at Cryogenic Temperatures
Published on: June 28, 2017
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水-氨混合物的低温特异性热容量,直至欧特西克
Bing Hong Chua1,2, Elodie Gloesener1, Mathieu Choukroun1
1Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, California 91109, United States.
概括
测量了水-氨系统的新热力学数据. 这些特定热容量 (Cp) 发现对于建模海洋世界和了解氨对水的关键行为的影响至关重要.
科学领域:
- 行星科学 行星科学
- 地质化学 地质化学
- 热力学是一种热力学.
背景情况:
- 强大的热力学数据对于建模海洋世界至关重要.
- 水氨系统是了解外太阳系组成和生命潜在起源的关键.
研究的目的:
- 为水-氨系统提供新的特定热容量 (Cp) 数据.
- 在相关的行星参数空间中研究温度和氨度的Cp趋势.
- 为了改进行星内部模型的状态方程.
主要方法:
- 差分扫描热量计 (DSC) 用于测量1bar的Cp.
- 测量是在低温 (184314 K) 和低氨质量分数 (5.226.9 wt %) 进行的.
- 在液相和部分化领域收集了数据.
主要成果:
- 液态相中的特定热容量 (Cp) 通常随温度的增加而增加.
- 观察到的Cp值偏离Tillner-Roth和Friend状态方程的负值 (1%至-10%),特别是在较低的温度下.
- 氨似乎抑制了超冷水的关键行为,其度比以前确定的要低.
结论:
- 这一新型数据集为研究水-氨热力学提供了高保真度.
- 这些发现表明,人们对氨对水的关键性质的影响有了改进的理解.
- 这些数据将增强海洋世界的模型,特别是关于冰海洋边界和内部条件的模型.
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