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Updated: Jun 21, 2025

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Seawater Sampling and Collection
Published on: June 17, 2009
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沿海海水pH值在途中绘制地图,使用带有光谱光度检测的自动船载分析仪
Hangqian Li1, Shu Wang2, Shulu Zheng3
1State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen, 361102, People's Republic of China; College of the Environment and Ecology, Xiamen University, Xiamen, 361102, People's Republic of China; Marine Biogeochemistry, Chemical Oceanography, GEOMAR Helmholtz Centre for Ocean Research Kiel, Kiel, 24148, Germany.
Talanta
|July 13, 2024
概括
一个新的自动水分析仪 (iSEA-pH) 精确测量海洋pH值,用于碳循环和酸化研究. 这种可在现场部署的仪器提供了对全球海洋监测至关重要的高频,准确的测量.
科学领域:
- 环境科学 环境科学
- 海洋学 海洋学 海洋学
- 分析化学 分析化学
背景情况:
- 精确测量海洋碳酸盐参数对于了解海洋碳循环,海洋酸化和二氧化碳去除至关重要.
- 需要能够在现场部署的仪器来实时评估海洋化学.
- 现有的方法可能缺乏全面海洋监测所需的精度或频率.
研究的目的:
- 开发一种高精度,自动化,现场部署的仪器,用于测量环境水的pH值.
- 为了实现适合评估动态海洋学过程的高频pH测量.
- 为了满足全球海洋酸化观测网络的严格准确性要求.
主要方法:
- 开发一个基于注射器的环境水分析仪,用于pH (iSEA-pH).
- 通过光谱测量测定pH值,使用纯化的指示染料 (meta-cresol紫色,thymol蓝色,phenol红色).
- 对温度,盐度和其他影响pH值测量的环境因素进行自动校正.
主要成果:
- 该iSEA-pH实现了高精度 (优于±0.001) 和高测量频率 (3.5分钟/样本).
- 短期分析给出了西太平洋表面海水的pH=7.8148 ± 0.0005 (n=104).
- 4天的长期分析显示pH=7.8148±0.0010 (n=200),测量频率为2h−1.1.
- 该仪器在中宇宙实验和海洋巡航中表现出卓越的现场性能,不确定性为±0.003.
结论:
- 开发的iSEA-pH系统提供了快速,准确和自主的现场pH测量.
- 该仪器符合全球海洋酸化观测网络的"气候"目标准确性要求.
- 在各种海洋环境中成功应用验证了其在海洋学研究中的实用性.
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