Relation between acid dissolution time in the vacuum test tube and time required for graphitization for AMS target preparation
書誌事項
- 公開日
- 2007-06
- 権利情報
-
- https://www.elsevier.com/tdm/userlicense/1.0/
- https://www.elsevier.com/legal/tdmrep-license
- https://doi.org/10.15223/policy-017
- https://doi.org/10.15223/policy-037
- https://doi.org/10.15223/policy-012
- https://doi.org/10.15223/policy-029
- https://doi.org/10.15223/policy-004
- DOI
-
- 10.1016/j.nimb.2007.01.176
- 公開者
- Elsevier BV
この論文をさがす
説明
Abstract Availability of an effective graphitization system is essential for the successful operation of an AMS laboratory for radiocarbon measurements. We have set up a graphitization system consisting of metal vacuum lines for cleaning CO 2 sample gas which is then converted to graphite. CO 2 gas from a carbonate sample is produced in vacuum in a test tube by injecting concentrated phosphoric acid. The tube is placed into a heated metal block to accelerate dissolution. However, we have observed systematic differences in the time required to convert the CO 2 gas to graphite under a hydrogen atmosphere, from less than 3 h to over 10 h. We have conducted a series of experiments including background measurements and yield measurements to monitor secondary carbon contamination and changes in isotopic fractionation. All of the tests show that the carbon isotope ratios remain unaffected by the duration of the process. We also used a quadrupole mass spectrometer (QMS) to identify possible contaminant gases. Contaminant peaks were identified at high mass (larger than 60) only for long duration experiments. This suggests a possible reaction between the rubber cap and acid fumes producing a contaminant gas that impeded the reduction of CO 2 .
収録刊行物
-
- Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms
-
Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms 259 (1), 330-334, 2007-06
Elsevier BV
