| Project/Area Number |
07554082
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| Research Category |
Grant-in-Aid for Scientific Research (A)
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| Allocation Type | Single-year Grants |
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| Section | 試験 |
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| Research Field |
地球化学
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| Research Institution | Ocean Research Institute, University of Tokyo |
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Principal Investigator |
NOZAKI Yoshiyuki University of Tokyo Ocean Research Institute, Professor, 海洋研究所, 教授 (70126142)
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| Co-Investigator(Kenkyū-buntansha) |
AMAKAWA Hiroshi University of Tokyo Ocean Research Institute, Res.Assoc, 海洋研究所, 助手 (60260519)
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| Project Period (FY) |
1995 – 1996
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| Project Status |
Completed (Fiscal Year 1996)
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| Budget Amount *help |
¥1,400,000 (Direct Cost: ¥1,400,000)
Fiscal Year 1996: ¥1,400,000 (Direct Cost: ¥1,400,000)
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| Keywords | Actinium / Radon / alpha-scintillation cells / photomultipliers / conuting electronics / MnO_2 fiber / ラドン娘核種 / マンガンファイバー / α線シンチレーション / フローシステム |
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| Research Abstract |
Actinium-227 is a nuclide belong to the ^<235>U decay chain. It's half life (21.7 years) is comparable within that of ^<210>Pb(t_<1/2>=22.7y). Although ^<210>Pb is widely used as a dating tool of lar, coastal and shelf sediments and a tracer of heavy metals in the marine environments, application of ^<227>Ac geochemical problems is limited due to absence of convienient method of determination. The purpose of this study is to develop a new counting method which includes detection of short-lived radon (^<219>Rn and ^<220>Rn) and its decay products by alpha-scintillation cells.
The system consists of two successive alpha-scintillation cells and photomultipliers, and counting electronics. Continuous helium gas flow purges ^<219>Rn and ^<220>Rn from MnO_2 fiber on which ^<227>Ac and ^<228>Ra are adsorbed and intuduce them into the alpha-scintillation cells. various experiments were carried out to find optional and prored that the system is useful for simoltaneous determinations of ^<227>Ac and ^<228>Ra.
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