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低温保护剂二甲基硫氧化物在超冷时对水的影响:一个分子动力学研究
1Dipartimento di Matematica e Fisica, Università Roma Tre, Via Della Vasca Navale 84, I-00146 Roma, Italy.
The Journal of chemical physics
|December 1, 2025
概括
水中的二甲基硫氧化物 (DMSO) 通过改变水的结构和动态来影响冷保存. 这种冷保护剂稳定高密度液态水,抑制冰的形成.
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:
- 甲基二硫化物 (DMSO) 对于冷保存至关重要.
- 了解DMSO在低温下对水的影响对于优化冷保护策略至关重要.
研究的目的:
- 为了研究DMSO的10%重量%水溶液如何在超冷过程中改变水的结构和动态.
- 为了阐明DMSO冷保护性质背后的分子机制.
主要方法:
- 使用了分子动力学模拟.
- 分析包括氧自介散射函数和氧-氧辐射分布函数.
- 在不同温度下检查水动力学和结构放松时间.
主要成果:
- 在DMSO溶液中的水动力学在轻度超冷状态下遵循模式合理论.
- 一个脆弱到强的交叉发生在稍低的温度 (≈225 K) 比在纯水 (≈230 K).
- 在230K以下,DMSO溶液显示出更快的水动力学和更高的密度,DMSO破坏了键并减少了四面体协调.
结论:
- 在低温下,DMSO稳定了水的高密度液相.
- 这种高密度水的稳定作用有助于DMSO的冷保护作用,通过抑制冰的形成.
- 这些发现为冷保存机制提供了分子洞察力.
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