从北大西洋提取的溶解有机物质的质子结合特性
Pablo Lodeiro1, Carlos Rey-Castro1, Calin David1
1Department of Chemistry, Physics, Environmental and Soil Sciences, University of Lleida - AGROTECNIO-CERCA Center, Rovira Roure 191, 25198 Lleida, Spain.
Environmental science & technology
|December 5, 2023
概括
海洋溶解有机物 (DOM) 具有独特的质子结合特性. 深海DOM显示结合异质性增加,表明持久的芳香化合物和可降解组的均积累.
科学领域:
- 海洋化学 海洋化学
- 生物地质化学生物地质化学
- 有机地化学 有机地化学
背景情况:
- 海洋溶解有机物 (DOM) 的特性对于了解海洋碳循环至关重要.
- 海洋DOM的热力学特性,特别是质子结合,仍然不完全理解.
- DOM上的功能组影响其在海洋环境中的反应性和相互作用.
研究的目的:
- 描述北大西洋海洋DOM中的质子结合点和亲和关系.
- 量化中位数内在质子结合亲和力 (log K̅H) 和异质性 (m).
- 调查这些属性如何随着深度而变化,并与DOM组成有关.
主要方法:
- 从北大西洋水样中提取DOM.
- 分析质子亲和谱以确定结合点分布.
- 介质内在质子结合亲和度和异质性参数的参数化.
主要成果:
- 海洋DOM中大约11.4%的碳原子具有用于离子物种结合的功能组.
- 北大西洋DOM中更多的酸性群体表现出比沿海DOM (3.82) 更高的亲和力 (log K̅H ≈4.01-4.02).
- 化学结合异质性 (m1) 随着深度的增加而增加,而较少的酸性组显示出相似性下降 (log K̅H 表面: 10.01,深度: 9.22) 和异质性 (m2) 随着深度的下降.
结论:
- 海洋DOM中的结合异质性与芳香化合物在各种化学形式的持久性有关.
- 容易降解,低亲和度组在深海中更加均地积聚.
- 这些发现增强了我们对海洋DOM热力学特性和生物地球化学命运的理解.
关键词:
在DOM DOM中,我们可以看到DOM DOM.唐南·多南是个很好的球员.酸 - 基的关系记录 K̅H 的日志非理想的竞争性吸附 (NICA)质子结合 质子结合海水;异质性;海水中的异质性.固相提取过程中的固相提取更多相关视频
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