与VSMOW相比,SLAP的绝对δ18O值显示出比以前确定的值要低得多的值
Anita Th Aerts-Bijma1, Albert C van Buuren1, Dipayan Paul1
1Centre for Isotope Research (CIO), Energy and Sustainability Research Institute Groningen, University of Groningen, Groningen, The Netherlands.
Rapid communications in mass spectrometry : RCM
|February 15, 2024
概括
对于SLAP水的确定的氧-18 (δ18O) 值为-55.5‰,但这项研究发现了一个更为负的值-56.33‰. 这种差异凸显了当前同位素测量技术和仪器校准的潜在问题.
科学领域:
- 地质化学 地质化学
- 环境科学 环境科学
- 分析化学 分析化学
背景情况:
- 标准光南极降水 (SLAP) 是同位素水量表的关键校准材料.
- 对于SLAP的共识δ18O值为-55.5‰,尽管一些实验室报告了更多的负值.
- 准确的 δ 18 O 值对于理解同位素尺度收缩和二次同位素至关重要.
研究的目的:
- 为了准确量化SLAP的δ18O值相对于VSMOW的δ18O值.
- 为了调查SLAP.O测量的 δ18O值的差异.
- 评估这些发现对同位素测量的影响.
主要方法:
- 类似于SLAP的水与丰富的水混合,以模拟VSMOW.
- 使用电子电离四极质谱法测量了O度.
- 对样本水和标准水的同位素成分使用光学光谱测量来确定.
主要成果:
- 该研究确定了SLAP的显著更负的δ18O值:-56.33 ± 0.03‰.
- 这一结果表明,即使在专家实验室中,也与预期值有很大差异.
- 对SLAP的绝对18O丰度计算为 (1887.98 ± 0.43) × 10-6 .
结论:
- 这些发现并没有改变VSMOW-SLAP尺度,但引发了测量准确性的问题.
- 这些结果对 δ18O 转移,分数因子和 Δ17O 计算有影响.
- 准确确定同位素标准对于可靠的科学测量至关重要.
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