在环境温度下水蒸气的异常凝结
Chenchen Guo1,2, Kun Yang1, Hairong Qin1
1School of Physics, Beijing Institute of Technology, Beijing 100081, China. yongjunlv@bit.edu.cn.
Physical chemistry chemical physics : PCCP
|February 29, 2024
概括
水蒸气凝结使纳米尺度的水滴稳定. 滴滴增长平衡了由于表面张力降低而导致临界大小的蒸发,从而导致双模尺寸分布.
科学领域:
- 物理化学 物理化学
- 纳米技术纳米技术
- 材料科学 材料科学 材料科学
背景情况:
- 水蒸气的均质凝结对于云形成和工业过程至关重要.
- 了解纳米级滴滴的行为是控制凝结现象的关键.
研究的目的:
- 研究纳米水滴在均凝结过程中的稳定机制.
- 阐明表面张力和蒸发在滴滴大小分布中的作用.
主要方法:
- 用分子动力学模拟来模拟环境温度下水蒸气凝结的情况.
- 分析的重点是滴滴核化,生长,碰撞,凝固和蒸发动态.
主要成果:
- 确定了大约12.5 Å的临界滴滴半径,以实现稳定的凝结.
- 滴滴的生长主要是由碰撞和凝固驱动的,通过快速蒸发来平衡.
- 表面张力显著降低到20 Å以下,增加了自由能量和驱动蒸发.
- 由于二次凝结,观察到水滴的双模尺寸分布.
结论:
- 纳米水滴可以通过增长和蒸发的动态平衡来实现稳定的凝结.
- 表面张力的曲率依赖性是控制这些滴滴的稳定性和尺寸分布的关键因素.
- 水分子的介电顺序影响表面张力,影响纳米尺度的滴滴行为.
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