MISC

2007年6月

Relation between acid dissolution time in the vacuum test tube and time required for graphitization for AMS target preparation

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS
  • Yusuke Yokoyama
  • ,
  • Yousuke Miyairi
  • ,
  • Hiroyuki Matsuzaki
  • ,
  • Fumiaki Tsunomori

259
1
開始ページ
330
終了ページ
334
記述言語
英語
掲載種別
DOI
10.1016/j.nimb.2007.01.176
出版者・発行元
ELSEVIER SCIENCE BV

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 CO2 sample gas which is then converted to graphite. CO2 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 CO2 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 CO2. (c) 2007 Elsevier B.V. All rights reserved.

Web of Science ® 被引用回数 : 69

リンク情報
DOI
https://doi.org/10.1016/j.nimb.2007.01.176
Web of Science
https://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=JSTA_CEL&SrcApp=J_Gate_JST&DestLinkType=FullRecord&KeyUT=WOS:000247535600061&DestApp=WOS_CPL
ID情報
  • DOI : 10.1016/j.nimb.2007.01.176
  • ISSN : 0168-583X
  • Web of Science ID : WOS:000247535600061

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