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在液体中的晶体纳米粒子的Phonon热泳
Semen N Semenov1, Martin E Schimpf2
1Institute of Biochemical Physics RAS, Kosygin Street 4, 119334 Moscow, Russia. sem@triniti.ru.
Physical chemistry chemical physics : PCCP
|March 18, 2024
概括
这项研究模拟了纳米粒子悬浮中的热扩散,揭示了热声子显著影响粒子运动 (热泳). 在极性溶剂中的10-100nm大小的纳米颗粒中,phonon驱动的热泳是主导的.
科学领域:
- 热力学是一种热力学.
- 纳米粒子科学 科学 纳米粒子科学
- 流体动力学 流体动力学
背景情况:
- 热泳描述了粒子运动,以应对温度梯度.
- 晶体纳米粒子具有高导热性,影响它们在悬浮中的行为.
- 了解热泳对于涉及粒子分离和操纵的应用至关重要.
研究的目的:
- 研究热声子在分子液体系统中晶体纳米颗粒的热泳中的作用.
- 将索雷特系数与差异联系起来,并确定语音机制主导的条件.
- 为了确定主导声热泳的粒子大小范围,并评估度极限.
主要方法:
- 开发一个非平衡热力学模型用于热扩散.
- 在极性溶剂中计算石墨和钻石纳米颗粒的声子索雷特系数.
- 对粒子大小依赖的导热率及其对热泳的作用的分析.
主要成果:
- 预计声子机制将在特定尺寸范围内的纳米颗粒 (10-100 nm对于极性溶剂中的石墨/钻石) 中主导热泳而不是滑动流.
- 颗粒大小显著影响声子热泳的优势,这是由于导热率的变化造成的.
- 热泳积累受到颗粒度的限制,从而降低了局部温度梯度.
结论:
- 热声子在晶体纳米粒子的热泳中发挥着至关重要的作用.
- 声波驱动的热泳取决于尺寸,并且发生在特定的纳米粒子尺寸窗口内.
- 必须考虑颗粒度,以优化热泳过程,因为高度会阻碍颗粒的运动.
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