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Determination of Pu concentration and its isotope ratio in Japanese soils by HR-ICP-MS.
https://repo.qst.go.jp/records/59055
https://repo.qst.go.jp/records/590557066b05f-7a9f-4ae3-bf4a-f19d7eb2a33f
| Item type | 会議発表用資料 / Presentation(1) | |||||
|---|---|---|---|---|---|---|
| 公開日 | 2002-06-05 | |||||
| タイトル | ||||||
| タイトル | Determination of Pu concentration and its isotope ratio in Japanese soils by HR-ICP-MS. | |||||
| 言語 | ||||||
| 言語 | eng | |||||
| 資源タイプ | ||||||
| 資源タイプ識別子 | http://purl.org/coar/resource_type/c_c94f | |||||
| 資源タイプ | conference object | |||||
| アクセス権 | ||||||
| アクセス権 | metadata only access | |||||
| アクセス権URI | http://purl.org/coar/access_right/c_14cb | |||||
| 著者 |
Muramatsu, Yasuyuki
× Muramatsu, Yasuyuki× Yoshida, Satoshi× Tanaka, Atsushi× 村松 康行× 吉田 聡× 田仲 睦 |
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| 抄録 | ||||||
| 内容記述タイプ | Abstract | |||||
| 内容記述 | The isotope composition of Pu (240Pu/239Pu ratio) is related to the source of the contamination. However, there is only a limited volume of quality data available on the levels and distributions of 239Pu and 240Pu isotopes in the environment. This is mainly due to the fact that 239Pu and 240Pu have similar alpha-particle energies and cannot be easily resolved by alpha spectrometry. We have recently developed a reliable method for determination of 239Pu and 240Pu by ICP-MS (Inductively Coupled Plasma Mass Spectrometry) using a quadrupole-type mass spectrometer (Yokogawa PMS-2000). We also have demonstrated the utility of the technique by measuring 240Pu/239Pu atom ratios in a series of international reference materials1 and soil samples from Chernobyl2. In this study we have used high resolution-type ICP-MS (HR-ICP-MS) to examine its analytical feasibility (e.g. detection limit) and determined concentrations of both 239Pu and 240Pu in Japanese soils. Samples (1 - 20 g, depending on the concentration level) were mixed with a known amount of 242Pu and digested with nitric acid. To the filtered leachate NaNO2 was added to convert chemical form of Pu to Pu (IV). Pu was separated with anion exchange resin (Dowex 1X8). Finally, NH4I (5%) - 10 M HCl solution (40 ml) was added to the column to elute Pu from the resin as Pu(III). Sufficient decontamination factors (104 - 105) for many matrix elements including U were obtained. The concentrations of 239Pu, 240Pu and 242Pu and their isotope ratios were measured with HR-ICP-MS (Finnigan Element). As a result, the detection limit determined using Pu standard and blank solutions (4% HNO3) was about 0.001 pg ml-1 (ppt) Pu for a counting time of 40 s. This value is about one order of magnitude better than the values obtained by the above-mentioned quadrupole-type ICP-MS. Relative standard deviation during the measurement was less than 1% at the concentration of >2 pg ml-1 of Pu. Compared with alpha-spectrometry, the ICP-MS method has significant advantages in terms of prompt measurement time, simple analytical procedures and capability of determining the 240Pu/239Pu ratio. Concentrations of Pu and its isotopic ratios were determined by this method in several soil samples from different areas in Japan. Levels of Pu in surface soils collected from forests were significantly higher than those from agricultural fields. Vertical distributions of Pu in soil showed an accumulation of this nuclide in the surface layer. The 240Pu/239Pu atom ratios observed in Japanese soil samples were around 0.17 (range: 0.15-0.19), except for very low ratios found in the Nagasaki area. |
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| 会議概要（会議名, 開催地, 会期, 主催者等） | ||||||
| 内容記述タイプ | Other | |||||
| 内容記述 | アジアー大平洋放射化学国際会議(APSORC2001) | |||||
| 発表年月日 | ||||||
| 日付 | 2001-11-01 | |||||
| 日付タイプ | Issued | |||||
