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Hyperpolarized Xenon for NMR and MRI Applications
Published on: September 6, 2012
ヘメタイト・イルメナイト系におけるラメラ磁気は,強い残留磁化現象の説明として用いられる
Peter Robinson1, Richard J Harrison, Suzanne A McEnroe
1Geological Survey of Norway, N-7491, Trondheim, Norway. peter.robinson@ngu.no
Nature
|August 2, 2002
まとめ
鉄・チタン酸化物における新しい磁気基底構造は,火山岩の異常な強い残留を説明する. 鉄鉄接触層を含むこの発見は,地質学的材料の磁気特性強化のメカニズムを明らかにしています.
科学分野:
- 地質物理学 地質物理学とは地質物理学です.
- ミネラル物理学 ミネラル物理学
- ロック・マグネティズム ロック・マグネティズム
背景:
- 火性岩や変形岩の磁気異常は,典型的には磁石と関連している.
- イルメニット・ヘメチット系の中間鉱物は強い残留を携えるが,通常は急速に冷却した火山岩にのみ保存される.
- イルメニット・ヘマチット・インターグロウスの岩石における異常に大きく安定した残留は観察されているが,完全には説明されていない.
研究 の 目的:
- イルメニット・ヘマチット・インターグロースを含む火山岩における異常な強さと安定した自然残留磁化の原因を調査する.
- 観測された高い磁気残留を考慮する新しい磁気基底構造を提案する.
主な方法:
- 酸化鉄酸化チタンの相における溶解後のラメラの分析.
- ナノスケール (1 nmまで) の磁性基構造の理論モデリング.
- 提案されたモデルに基づいて,飽和磁化の推定.
主要な成果:
- 100マイクロメートルから1ナノメートルまでの厚さを持つ溶解後のラメラが観察されました.
- ヘマタイトとイルメナイトの間の鉄鉄"接触層"を含む新しい鉄磁性基底構造を提案した.
- 推定飽和磁化は55 kA m(-1までであり,純粋なヘマタイトよりも大幅に高く,高い強制性を維持しています.
結論:
- 提案されている鉄・鉄質の"接触層"は,ある火山岩で観察される例外的に強い残留磁化のためのメカニズムを提供します.
- この基底構造は,酸化物の含有量が少ない岩石が,どのように重要な磁気異常を示すことができるかを説明します.
- この発見は,地質学的記録における磁気シグネチャーの理解と,磁気材料の応用に潜在的に影響を及ぼします.
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