トランジエント・フェーズ誘発核化

Sirota¹, Herhold

¹Exxon Research and Engineering Company, Corporate Research Science Laboratory, Route 22 East, Annandale, NJ 08801, USA.

Science (New York, N.Y.)

|January 23, 1999

まとめ

研究者らは,ヘクサデカンの結晶化中に一時的な転移安定の回転器相を観察した. この段階はこの段階です.

科学分野:

マテリアルサイエンス材料科学
クリスタルグラフィーです.
物理化学物理化学

背景:

超冷却メルトからの結晶化は,材料加工に不可欠です.
メタステーブル・フェーズを理解することは,最終的な結晶構造を制御するための鍵です.
ヘクサデカンの結晶化は,相変遷を研究するためのモデルシステムを提供します.

研究の目的:

ヘクサデカネにおける一時的なメタステーブル・ローター・フェーズを直接観察し,特徴づけること.
超冷却の限界を決定する際に,この一時的な相が果たす役割を調査する.
n-アルカンの結晶化動態を解明し,一時的な相の性質を確認する.

主な方法:

直接観測のため,時間解像度の同期型X線散射を用いた.
n-アルケンの同類系の結晶化運動を測定した.
超冷却の限界を理解するために,熱力学的安定性分析を使用した.

主要な成果:

ヘクサデカンの結晶化中に,一時的な転移性ローターフェーズが直接観察されました.
超冷却の限界は,この一時的な相の熱力学的安定性によって決まります.
メタスタビリティから一時的なメタスタビリティへの結晶化運動のクロスオーバーが特定されました.

結論:

トランジント・メタステーブル・ローター・フェーズは,ヘクサデカネの結晶化において重要な役割を果たします.
観測されたメタスタビリティのクロスオーバーは,n-アルケンの結晶化動態を説明する.
直接観測は,超冷却現象における一時的な相の性質と重要性を確認しています.

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