Storage and Hydrolysis of Seawater Samples for Inorganic Carbon Isotope Analysis
Storage and Hydrolysis of Seawater Samples for Inorganic Carbon Isotope Analysis
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用于无机碳同位素分析的海水样品的储存和水解
DOI：
10.1017/s0033822200057520
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发表时间：
2013
期刊：
影响因子：
8.3
通讯作者：
R. Shanks
中科院分区：
文献类型：
--
作者：
C. Bryant;S. Henley;C. Murray;R. Ganeshram;R. Shanks
使用铝箔袋并通过冷藏和冷冻储存，对海水样品的总无机碳 (ΣCO2)、稳定碳同位素 (δ13C) 和放射性碳 (14C) 的保存进行了测试。目的是以最小的储存影响保存代表性样品，但不使用氯化汞中毒等有毒方法。样品水解成 CO2 是基于现有方法。使用储存在箔袋中的去离子水的 IAEA-C2 标准结果显示完全反应产率，14C 结果在共识值的 2σ 范围内，并且 δ13C 内部一致，表明不存在与箔袋相关的程序效应。对于来自英国法夫郡 Elie Ness 沿海地点的冷冻和冷藏海水样品，14C 结果在整个存储时间内在统计上无法区分。 ΣCO2 浓度和 δ13C 的离散度在其他研究中观察到的通过酸化或使用氯化汞保存的湖水和海水样品的离散度范围内。然而，与冷藏样品相比，冷冻样品的 ΣCO2 和 δ13C 变化较小。铝箔袋更轻，运输更安全，成本与玻璃瓶相似，并且允许在现场收集样品并转移到水解容器，而无需将样品暴露在大气中。将海水样品储存在铝箔袋中被认为是 ΣCO2、δ13C 和 14C 中毒的可靠替代方法，并且建议将样品冷冻储存时间超过一周。
Preservation of seawater samples was tested for total inorganic carbon (∑CO2), stable carbon isotope (δ13C), and radiocarbon (14C) applications using foil bags and storage by refrigeration and freezing. The aim was to preserve representative samples with minimal storage effects but without using toxic methods such as mercuric chloride poisoning. Hydrolysis of samples to CO2 was based on existing methods. Results of IAEA-C2 standard used with deionized water stored in the foil bags showed complete reaction yields, 14C results within 2σ of the consensus value, and δ13C that were internally consistent, indicating that there were no procedural effects associated with the foil bags. 14C results were statistically indistinguishable across the storage times, for frozen and refrigerated seawater samples from a coastal site, Elie Ness, Fife, UK. The scatter of ∑CO2 concentrations and δ13C was within scatter observed in other studies for lake- and seawater samples preserved by acidification or using mercuric chloride. However, both ∑CO2 and δ13C were less variable for frozen samples compared with refrigerated samples. The foil bags are lighter, safer to transport, and similar in cost to glass bottles and allow sample collection in the field and transfer to the hydrolysis vessel without exposure of the sample to atmosphere. Storage of seawater samples in the foil bags was considered a reliable, alternative method to poisoning for ∑CO2, δ13C, and 14C, and freezing the samples is recommended for storage time beyond a week.