大量の氷の超高速加熱と融解
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
まとめ
科学者は,OHのストレッチモードを刺激することによって,氷の過熱を実証しました. これにより,氷は融解点以上の温度に達し,融解することなく,以前は氷で達成するのが困難だった現象を達成することができます.
科学分野:
- 物理化学 物理化学
- マテリアルサイエンス 材料科学
- 熱力学は熱力学である.
背景:
- 超熱は固体における既知の現象で,温度が相変化なしに融点を超える現象である.
- 氷は通常,水素結合の方向性による欠陥を含み,過熱を妨げます.
- シミュレーションでは,欠陥のない氷を過熱させることができ,実験的実現可能性を示唆しています.
研究 の 目的:
- 実験的に氷を過熱する可能性を調査するために.
- 氷の超高温状態を達成するための方法を探求する.
- 氷の熱的行動における分子振動の役割を理解する.
主な方法:
- 氷の水分子のOH伸縮モードの刺激.
- 氷のサンプルにおける温度変化の実験的観測.
- 270 Kの250ピコ秒間隔で氷の行動を監視する.
主要な成果:
- OHのストレッチモードを刺激することで,氷の過熱を達成しました.
- 20 +/- 2 Kの平均気温上昇が観察されました.
- 250ピコ秒間,溶けることなく超熱状態を維持した.
結論:
- 氷の実験的な過熱は可能である.
- ターゲティングされた分子刺激は,氷の自然欠陥構造を克服することができます.
- この発見は,氷の特性や相変化の研究に新たな道を開く.
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