無水および水素化セメントの分子シリケートおよびアルミナート種
Aditya Rawal1, Benjamin J Smith, George L Athens
1Department of Chemical Engineering, University of California, Santa Barbara, California 93106, USA.
Journal of the American Chemical Society
|May 12, 2010
まとめ
先進的な固体核磁気共振 (NMR) スペクトロスコピーは,無水性および水性セメントの異なる分子構造を明らかにします. この技術は,シリケートとアルミナートの種類を区別し,セメントの水分化と設定プロセスに関する洞察を提供します.
科学分野:
- 材料科学 材料科学とは
- 化学 化学は化学です.
- スペクトロスコーピーは,スペクトロスコーピーを用います.
背景:
- シメントの組成と分子構造を理解することは,水分化と設定を制御するために不可欠です.
- 複雑な分子種をセメントで解明するには,高度な分析技術が必要である.
研究 の 目的:
- 先進的な固体状態NMRを用いて無水および水素化されたセメントの分子構造を決定する.
- 異なる分子種を区別し,セメントの水分化と設定中に変化を追跡する.
主な方法:
- 一次元と二次元 (2D) の固体 (29) Siと (27) Alのマジック・アングル・スピニングNMRを用いた.
- T(1) - リラクゼーション時間 - 化学シフト - アニソトロピー - フィルタリングされた測定を非常に高い磁場 (19T) で使用した.
- シリケートおよびアルミナート種の定量分析のためのX線光と相関したNMRスペクトル.
主要な成果:
- 複雑なセメントスペクトルの様々なシリケートおよびアルミナート部分の共鳴を解き,割り当てました.
- 定量化された結晶および無秩序のシリケートおよびアルミナート種は,無水および水素化されたセメントの両方で存在します.
- 水性セメントにおける水/ヒドロキシル群と特定の (27) Alおよび (29) Si種の間の相互作用が確立されています.
- 水分化の過程でカルシウムシリケートおよびアルミナート成分から分離している特徴的な鉄含有シリケート種.
結論:
- 固体NMRは,セメントの組成と水分化の詳細な分子洞察を提供します.
- 異なるセメントタイプの異なる分子特性 (例えば,白いポートランドと灰色の油井) は,それらの水分化行動と相関しています.
- 先進的なNMR方法論により,セメント材料の正確な特徴づけが可能です.
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