水のガラス変容の振る舞いを,超静止された無機ガラスと比較して明らかにする
Yuanzheng Yue1, C Austen Angell
1Section of Chemistry, Department of Life Sciences, Aalborg University, DK-9000 Aalborg, Denmark.
Nature
|February 20, 2004
まとめ
水 水 水 水 でした.
科学分野:
- マテリアルサイエンス 材料科学
- 物理化学 物理化学
- 熱力学は熱力学である.
背景:
- ガラスの形成は,幅広い液体範囲または急速な冷却を有する液体にとって一般的です.
- 物質は再加熱時に異なる行動を示します:良いガラス形成剤は超冷却液体に移行し,他のものは結晶化します.
- 水のガラスの移行は数十年にわたって議論されており,136 Kで広く受け入れられているが異常な移行があります.
研究 の 目的:
- 再加熱中の過熱した無機ガラスの振る舞いを調査する.
- 無機ガラスの熱性能をガラスの水と比較するために.
- 水のガラス化過程の性質と存在を再評価する.
主な方法:
- ハイパークエンチされた無機ガラスの詳細な熱測定特性.
- 結晶化前の移行を観察するために,無機ガラスの加熱実験を行った.
- 無機ガラスとガラスの水の間の熱データ比較分析.
主要な成果:
- ハイパークエンチされた無機ガラスは,ガラスの移行温度に達する前に結晶化しません.
- ガラスのような水で観測された熱効果は,真のガラスの移行の"影"に似ています.
- 広く受け入れられている水中の136 Kの移行は,主要なガラスの移行ではありません.
結論:
- 水の直接的なガラス化は,典型的な条件下で実験的に探査することはできません.
- 水の真のガラス化は,高温で起こり,結晶化によってマスクされます.
- 水の136 K移行の異常な行動は,それが二次的効果であることで説明されます.
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