超冷糖醇的非线性物理衰老是由通过冷却实验监测的最大向上理想温度步骤引起的
Marceau Hénot1, François Ladieu1
1SPEC, CEA, CNRS, Université Paris-Saclay, CEA Saclay Bat 772, 91191 Gif-sur-Yvette Cedex, France.
The Journal of chemical physics
|June 13, 2023
概括
使用快速加热和冷却研究了超冷糖醇老化. 工具-纳拉亚纳斯瓦米-莫伊尼汉 (TNM) 形式主义准确地描述了液体.
科学领域:
- 物理化学 物理化学
- 材料科学 材料科学 材料科学
- 玻璃过渡物理 玻璃过渡物理
背景情况:
- 超冷液体表现出复杂的衰老动态.
- 了解物理衰老对于预测材料性质至关重要.
- 糖醇作为研究玻璃过渡现象的模型系统.
研究的目的:
- 为了研究超冷糖醇在高温阶段的物理衰老.
- 开发和验证一种新的实验方法来研究远离平衡的动态.
- 量化评估工具-纳拉亚纳斯瓦米-莫尼汉 (TNM) 形式主义的适用性.
主要方法:
- 使用一种新的技术,涉及薄型甘油薄膜的快速加热 (高达60,000K/s).
- 监测介电损失,以追踪温度干扰后的液体放松.
- 应用TNM形式主义,调整了冷却和加热阶段的非线性参数.
主要成果:
- 在TNM形式主义成功地描述了糖醇对大温度步骤的反应,甚至远离平衡.
- 对于加热和冷却阶段,需要不同的非线性参数,突出非平衡效应.
- 该研究使得理想温度步骤的精确量化成为可能,以最大限度地减少加热过程中的放松.
- 虚构温度演变的重建揭示了高度非线性液体行为.
结论:
- TNM方法提供了对超冷液态动态的宝贵见解,但有局限性.
- 新的实验设置对于研究超冷液体中远离平衡现象是有效的.
- 这项研究阐明了短期流体反应和长期老化过程之间的关系.
相关概念视频
Effects of Temperature on Free Energy
25.7K
The spontaneity of a process depends upon the temperature of the system. Phase transitions, for example, will proceed spontaneously in one direction or the other depending upon the temperature of the substance in question. Likewise, some chemical reactions can also exhibit temperature-dependent spontaneities. To illustrate this concept, the equation relating free energy change to the enthalpy and entropy changes for the process is considered:
25.7K
Temperature Dependent Deformation
174
In a nonhomogeneous rod made up of steel and brass, restrained at both ends and subjected to a temperature change, several steps are involved in calculating the stress and compressive load. Due to the problem's static indeterminacy, one end support is disconnected, allowing the rod to experience the temperature change freely. Next, an unknown force is applied at the free end, triggering deformations in the rod's steel and brass portions. These deformations are then calculated and added...
174
Effect of Temperature Change on Reaction Rate
4.2K
The Arrhenius equation,
4.2K
Phase Transitions: Melting and Freezing
12.5K
Heating a crystalline solid increases the average energy of its atoms, molecules, or ions, and the solid gets hotter. At some point, the added energy becomes large enough to partially overcome the forces holding the molecules or ions of the solid in their fixed positions, and the solid begins the process of transitioning to the liquid state or melting. At this point, the temperature of the solid stops rising, despite the continual input of heat, and it remains constant until all of the solid is...
12.5K
Physical Methods for Controlling Microbial Growth: Temperature
149
Heat is a widely used method to control microbial growth by targeting and denaturing cellular proteins, thereby killing or inactivating microbes. This method's effectiveness is quantified using parameters such as the thermal death point (TDP), thermal death time (TDT), and decimal reduction time (D value). TDP represents the lowest temperature at which all microorganisms in a liquid suspension are eliminated within 10 minutes, whereas TDT is the time necessary to achieve sterilization at a...
149
Freezing Point Depression and Boiling Point Elevation
35.2K
Boiling Point Elevation
The boiling point of a liquid is the temperature at which its vapor pressure is equal to ambient atmospheric pressure. Since the vapor pressure of a solution is lowered due to the presence of nonvolatile solutes, it stands to reason that the solution’s boiling point will subsequently be increased. Vapor pressure increases with temperature, and so a solution will require a higher temperature than will pure solvent to achieve any given vapor pressure, including one...
The boiling point of a liquid is the temperature at which its vapor pressure is equal to ambient atmospheric pressure. Since the vapor pressure of a solution is lowered due to the presence of nonvolatile solutes, it stands to reason that the solution’s boiling point will subsequently be increased. Vapor pressure increases with temperature, and so a solution will require a higher temperature than will pure solvent to achieve any given vapor pressure, including one...
35.2K


