超快速超热和融化大量的冰
H Iglev1, M Schmeisser, K Simeonidis
1Physik-Department, Technische Universität München, James-Franck-Strasse, D-85748 Garching, Germany. higlev@ph.tum.de
Nature
|January 13, 2006
概括
科学家们通过激发其OH拉伸模式来证明冰的超热. 这使得冰在没有融化的情况下达到点以上的温度,这是以前很难用冰实现的现象.
科学领域:
- 物理化学 物理化学
- 材料科学 材料科学 材料科学
- 热力学是一种热力学.
背景情况:
- 过热是固体中已知的现象,温度在没有相变的情况下超过点.
- 冰通常含有由于键方向性的缺陷,阻碍过热.
- 模拟显示无缺陷的冰可以被超热,这表明实验可行性.
研究的目的:
- 为了研究实验性加热冰的可能性.
- 探索在冰中实现超热状态的方法.
- 了解分子振动在冰的热行为中的作用.
主要方法:
- 激发冰中的水分子的OH拉伸模式.
- 在冰样本中实验观察温度变化.
- 在270 K的250皮秒间隔内监测冰的行为.
主要成果:
- 通过激发OH拉伸模式来实现冰的超热.
- 观察到平均温度上升20 +/- 2K.
- 保持过热状态250比秒,没有融化.
结论:
- 冰的实验性超热是可能的.
- 有针对性的分子激发可以克服冰中的自然缺陷结构.
- 这一发现为研究冰的特性和相位过渡开辟了新的途径.
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