関連する実験動画
Updated: Jul 16, 2026
06:54
Preparing Silica Aerogel Monoliths via a Rapid Supercritical Extraction Method
Published on: February 28, 2014
シリケートガラスの密度の高い氷のような成分である水
1P. Richet, Laboratoire de Physique des Geomateriaux, Unite de Recherche Associee CNRS 734, Institut de Physique du Globe, 4, Place Jussieu, 75252 Paris Cedex 05, France. A. Polian, Laboratoire de Physique des Milieux Condenses, Unite de.
Science (New York, N.Y.)
|July 17, 1998
まとめ
アンデサイトガラスの溶けた水は,ヒドロキシルイオンか分子かに関わらず,密度の高い氷 VII.に似た性質を持っています. これは,水素結合が溶解を誘導するもので,体積の変化ではないことを示しており,高水分含有量はシア・モジュールを減少させます.
科学分野:
- 地質化学 地質化学
- マテリアルサイエンス 材料科学
- ミネラル物理学 ミネラル物理学
背景:
- 地質学的物質における水の振る舞いを理解することは,地球のプロセスを解釈する上で極めて重要です.
- シリケートガラスの水の溶解機構と物理的影響は完全に理解されていません.
- アンデサイトガラスは,マグマの性質を研究するためのモデルシステムとして機能しています.
研究 の 目的:
- アンデサイトガラスに溶けた水の物理的性質を調査する.
- アンデサイトガラスの水の部分モラー体積と質量モジュールを測定する.
- 水の種化,水素結合,ガラスの特性との関係を調査する.
主な方法:
- 環境条件での密度測定.
- 音響特性を探査するためのブリュルーイン散射スペクトロスコーピー.
- ガラスの構造内における水の種化 (ヒドロキシル対分子) の分析.
主要な成果:
- 溶解した水は,濃度に関係なく12 ± 0.5cm3/molの部分モラー体積を示します.
- 溶けた水の質量分子は18 ± 3 GPaで,氷のVII.と比較できます.
- 水の種種化は,システムの体積ではなく,エントロピーによって支配され,水の1重%以上では,シア・モジュールが著しく減少する.
結論:
- 水素結合は,アンデサイトガラスの水溶解の重要な要因です.
- ガラスの中の水の振る舞いは,氷VIIのそれと類似しており,同様の構造的秩序を示唆しています.
- 高濃度の水は,シリケートガラスの機械的完全性を著しく弱める.
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