まとめ
溶けた水は,花岩の溶解物におけるセシウム134の拡散を著しく加速する. この発見は,水性シリケート溶液における化学プロセスの均衡の時間がより速いことを示唆している.
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
背景:
- 地質学的溶融におけるイオン拡散の理解は,地化学モデリングに不可欠です.
- 以前の研究では,乾燥した花岩ガラスが緩やかな拡散率を示していることが示されています.
研究 の 目的:
- 溶けた水のセシウム134の自己拡散に対する影響を,花岩の溶融で調査する.
- 拡散係数と活性化エネルギーの変化を定量化するために.
主な方法:
- 放射性トレーサー (セシウム-134) の拡散実験が行われました.
- 実験は,6.1~6.3重量パーセントの溶けたH2Oを積んだ花岩の溶け物で実施した.
- 拡散は700-800°Cと2 kbar.で測定されました.
主要な成果:
- セシウム134の拡散係数は,水の存在下では3〜4倍の大きさであった.
- 拡散のための活性化エネルギーは約20kcal/molであり,乾燥ガラスよりも著しく低かった.
- セシウムの拡散性はアレニウス方程式に従った:D = 7.19 x 10(-5) exp (-19.52 x 10(3) /RT).
結論:
- 溶けた水は,花岩の溶融物におけるイオン移動性を劇的に高めます.
- この流動性の向上は,水性溶融の地質学的プロセスにおける化学的均衡の時間を大幅に短縮することを意味する.
- この発見は,様々な地質学的環境における融解の行動を理解するための意味を持つ.
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