稳定同位素参考材料和尺度定义 - - 2024年国际原子能机构专家会议的成果
Federica Camin1, Dinka Besic1, Paul J Brewer2
1Terrestrial Environmental Radiochemistry Laboratory, Division of Physical and Chemical Sciences, Department of Nuclear Sciences and Applications, International Atomic Energy Agency, Vienna, Austria.
Rapid communications in mass spectrometry : RCM
|April 25, 2025
概括
国际原子能机构第十二次会议标准化了碳和氧同位素尺度,承认了VPDB和VPDB-LSVEC尺度. 对于和硫同位素尺度需要进一步研究.
科学领域:
- 地质化学 地质化学
- 分析化学 分析化学
- 环境科学 环境科学
背景情况:
- 稳定同位素参考材料对于准确的地球化学和环境分析至关重要.
- 关于同位素三角洲尺度的国际共识确保了全球科学数据的可比性.
- 国际原子能机构 (IAEA) 在协调参考材料的努力方面发挥着关键作用.
研究的目的:
- 报告国际原子能机构关于稳定同位素参考材料的第十二次会议达成的共识.
- 建立碳和氧同位素三角洲尺度的标准化定义.
- 为了确定在同位素分析和参考材料开发方面需要改进的领域.
主要方法:
- 在国际专家之间建立对同位素三角洲尺度定义的共识.
- 碳同位素三角尺度 (VPDB和VPDB-LSVEC) 和氧同位素三角尺度 (VSMOW-SLAP和VPDB) 的定义.
- 对参考材料的值和不确定性赋值方法的讨论.
主要成果:
- 关于两个碳同位素三角度表的协议:VPDB和VPDB-LSVEC,具有公认的转换不确定性.
- 定义两个氧同位素三角尺度:VSMOW-SLAP和VPDB.
- 确定对和硫同位素三角洲尺度的第二级定义点的需求.
- 鼓励实验室在分析"不可交换"和碳酸氧时提高一致性.
结论:
- 已经定义了碳和氧的标准化同位素三角洲尺度,提高了实验室间的可比性.
- 对于温室气体和和硫等其他元素,需要进一步开发参考材料和分析方法.
- 通过国际原子能机构等组织的持续国际合作对于推动稳定同位素科学的发展至关重要.
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