超冷水在高压下在剪切下保持其普遍的核化行为吗?
Snehitha Srirangam1, Mangesh Bhendale1, Jayant K Singh1,2
1Department of Chemical Engineering, Indian Institute of Technology Kanpur, Uttar Pradesh, 208016, India. jayantks@iitk.ac.in.
Physical chemistry chemical physics : PCCP
|August 7, 2023
概括
高压增强了剪切下的冰核形成,这对于冷保存至关重要. 最佳切割速率显示非单调的压力依赖性,影响生物样本的保存.
科学领域:
- 物理化学 物理化学
- 生物物理学的生物物理.
- 材料科学 材料科学 材料科学
背景情况:
- 高压对于蛋白质结晶和冷保存至关重要,防止生物样品结.
- 了解高压下剪切下的冰核形成对于这些应用至关重要.
研究的目的:
- 为了研究在各种高压下在剪切下超冷水中的冰核化行为.
- 探索在高压下剪切系统的普遍核化动力学.
主要方法:
- 使用TIP4P/Ice模型计算核化速率,并使用播种方法扩展经典核化理论 (CNT).
- 分析了运输和热力学属性的压力依赖性,包括剪切率.
- 在1至1000bar和240K的压力下进行的模拟.
主要成果:
- 观察到 Δμliq-ice 和粘度下降,随着压力上升,扩散性增加.
- 证明核化速率对剪切的非单调依赖性,在最佳剪切速率 (107108 s-1) 处达到峰值.
- 揭示了最佳剪速的非单调压力依赖,可能是由于斯托克斯-爱因斯坦关系的违规.
结论:
- 高压显著影响剪切下的冰核化动力学.
- 核形成的最佳切割速率取决于压力,并表现出非单调的行为.
- 研究结果提供了极端条件下的冷保存和蛋白质结晶的见解.
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