| DOI: | 10.2172/1252619
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| 报告号: | LLNL-TR--665865
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| 报告题名: | California GAMA Special Study. Development of a Capability for the Analysis of Krypton-85 in Groundwater Samples |
| 作者: | Visser, Ate; Bibby, Richard K.; Moran, Jean E.; Singleton, Michael J.; Esser, Bradley K.
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| 出版年: | 2015
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| 发表日期: | 2015-06-01
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| 总页数: | 25
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| 国家: | 美国
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| 语种: | 英语
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| 英文摘要: | A capability for the analysis of krypton-85 (85Kr) in groundwater samples was developed at LLNL. Samples are collected by extracting gas from 2000-4000 L of groundwater at the well, yielding approximately 0.2 cm3 STP krypton. Sample collection takes 1 to 4 hours. Krypton is purified in the laboratory using a combination of molecular sieve and activated charcoal traps, and transferred to a liquid scintillation vial. The 85Kr activity is measured by liquid scintillation on a Quantulus 1220 liquid scintillation counter from PerkinElmer. The detection limit for a typical 0.2 cm3Kr sample size is 11% of the present day activity in air, corresponding to the decay corrected activity in air in 1987. The typical measurement uncertainty is below 10% for recently recharged samples. Six groundwater samples were collected, purified and counted. 85Kr was not detected in any of the samples counted at LLNL. 85Kr was detected by the low level counting laboratory of Bern University in all samples between 1.5 and 6.6 decays per minute per cm3 krypton, corresponding to decay corrected activities in air between 1971 and 1985. The new capability is an excellent complement to tritium-helium, expanding the existing suite of age dating tools available to the GAMA program (35S, 3H/3He, 14C and radiogenic helium). 85Kr can replace 3H/3He in settings where 3H/3He ages are impossible to determine (for example where terrigenic helium overwhelms tritiogenic helium) and provides additional insight into travel time distributions in complex mixed groundwater systems. |
| URL: | http://www.osti.gov/scitech/servlets/purl/1252619
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| Citation statistics: |
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| 资源类型: | 研究报告
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| 标识符: | http://119.78.100.158/handle/2HF3EXSE/41857
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| Appears in Collections: | 过去全球变化的重建
影响、适应和脆弱性
科学计划与规划
气候变化与战略
全球变化的国际研究计划
气候减缓与适应
气候变化事实与影响
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| 1252619.pdf（728KB） | 研究报告 | -- | 开放获取 | | View
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| Recommended Citation: | |
Visser, Ate,Bibby, Richard K.,Moran, Jean E.,et al. California GAMA Special Study. Development of a Capability for the Analysis of Krypton-85 in Groundwater Samples. 2015-01-01.
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