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Determination of the Gas-phase Acidities of Oligopeptides
Published on: June 24, 2013
氷河期 - 氷河間における海洋pHの安定性は,フォラミニファーの溶解率から推測される
David M Anderson1, David Archer
1NOAA Paleoclimatology Program and University of Colorado, 325 Broadway, Boulder, Colorado 80303, USA. dma@ngdc.noaa.gov
Nature
|March 8, 2002
まとめ
海洋のpHと炭酸塩化学は,大気中のCO2の調節に不可欠です. この研究では,氷河期の大西洋の炭酸イオン濃度が低下し,以前の全海洋のpHシフト理論に異議を唱えた.
科学分野:
- パレオセアノグラフィー
- 地質化学 地質化学
- 気候科学 気候科学
背景:
- 海洋のpHと炭酸塩化学は,長期にわたって大気中のCO2の調節に大きく影響する.
- 過去の海洋のpHを理解することは,地球規模の炭素循環を理解するために不可欠です.
- 過去の研究では,最後の氷河期最大期 (LGM) の間,より基本的な全海洋のpHを示唆していた.
研究 の 目的:
- 氷河海における炭酸イオン濃度とpHを復元する.
- LGMの間,世界の炭素循環における海洋の役割を調査する.
- ボロンイソトープに基づいた以前の発見と新しい再構築を比較する.
主な方法:
- フォラミニファーの動物集団のCLIMAPデータセットを使用.
- フォラミニフェラにおけるカルシウム炭酸溶解の程度を分析する.
- 炭酸イオン濃度を再構築し,海のpHを推論する.
主要な成果:
- 大西洋の氷河における炭酸イオン濃度 (~20マイクロモルkg-1) の減少が観察されました.
- インド洋と太平洋の炭酸イオン濃度の変化は,今日と比較してほとんどありませんでした.
- 太平洋の3,000m以下の炭素酸イオン濃度 (~5マイクロモルkg-1) のわずかな増加が認められた.
結論:
- この研究は,海洋のpHの再配置を示し,海洋循環パターンの変化と関連している可能性がある.
- 結果は,以前,ボロン同位体から推測されたように,LGMの間に全海洋のpHの有意な変化を支持しません.
- フォラミニフェラにおけるカルシウム炭酸の溶解は,過去の海洋化学を再構築するための貴重な代理物を提供します.
関連する概念動画
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Mixtures of Acids
The pH of a solution containing an acid can be determined using its acid dissociation constant and initial concentration. If a solution contains two different acids, then its pH can be determined using one of several methods depending on the relative strength of the acids and their dissociation constants.
In a strong and weak acid mixture, the strong acid dissociates completely and becomes a source of almost all the hydronium ions present in the solution. In contrast, the weak acid shows...
In a strong and weak acid mixture, the strong acid dissociates completely and becomes a source of almost all the hydronium ions present in the solution. In contrast, the weak acid shows...

