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S. R. Joshi - One of the best experts on this subject based on the ideXlab platform.
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Determination of Plutonium 240/239 ratios in Lake Ontario sediments
Journal of the American Society for Mass Spectrometry, 1991Co-Authors: L. W. Green, F. C. Miller, J. A. Sparling, S. R. JoshiAbstract:A thermal ionization mass spectrometric procedure was developed for determination of 240/239 ratios in subpicogram quantities of Plutonium (Pu), and was applied to Pu extracted from Lake Ontario sediment. The detection limit was ∼ 4 fg of Pu and the precision of 240/239 ratio measurement was ∼ 7% in the 0.07–0.42 pg range. Results of sediment analyses at various depths showed in all cases 240/239 ratios near the mean global fallout value of 0.176 ± 0.014. The lack of variability of the ratios with depth negated the use of Pu, present in excess in the near-surface samples due to leakage from a nearby reprocessing plant, as a geochronological meter. The 240/239 ratio of the leakage Pu appeared to be very similar to that of fallout Pu.
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determination of Plutonium 240 239 ratios in lake ontario sediments
Journal of the American Society for Mass Spectrometry, 1991Co-Authors: L. W. Green, F. C. Miller, J. A. Sparling, S. R. JoshiAbstract:A thermal ionization mass spectrometric procedure was developed for determination of 240/239 ratios in subpicogram quantities of Plutonium (Pu), and was applied to Pu extracted from Lake Ontario sediment. The detection limit was ∼ 4 fg of Pu and the precision of 240/239 ratio measurement was ∼ 7% in the 0.07–0.42 pg range. Results of sediment analyses at various depths showed in all cases 240/239 ratios near the mean global fallout value of 0.176 ± 0.014. The lack of variability of the ratios with depth negated the use of Pu, present in excess in the near-surface samples due to leakage from a nearby reprocessing plant, as a geochronological meter. The 240/239 ratio of the leakage Pu appeared to be very similar to that of fallout Pu.
Brit Salbu - One of the best experts on this subject based on the ideXlab platform.
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Determination of Plutonium-239 + Plutonium-240 and Plutonium-241 in environmental samples using low-level liquid scintillation spectrometry.
The Analyst, 1992Co-Authors: Helge E. Bjørnstad, Brit SalbuAbstract:A radiochemical method for the simultaneous determination of 239Pu + 240Pu and 241Pu in environmental samples has been developed. In the course of the analysis a 236Pu tracer was used for estimating the chemical yield of Plutonium isotopes. After suitable pre-treatment of the sample, the Plutonium nuclides in solution were coprecipitated with iron(III) hydroxide and calcium oxalate and isolated further from impurities and interfering radionuclides by means of anion-exchange chromatography. Plutonium isotopes in the eluate (NH4I-HCI) were converted into nitrate form and then extracted with 20 ml of 5% bis(2-ethylhexyl) hydrogen phosphate extractive cocktail. The final organic solution was measured spectrometrically using an ultra-low-level liquid scintillation spectrometer, Quantulus (LKB, 1220 Wallac). The chemical yields of Plutonium range from 25 to 50% for 100 I of sea-water and 30 to 60% for 40 g of dried soil sample. The counting efficiencies are nearly 100% for 239Pu + 240Pu and 48.8% for 241Pu, respectively. The detection limits were estimated to be 0.20 mBq for 239Pu + 240Pu and 2.2 mBq for 241Pu, respectively. The proposed procedure has been tested for the simultaneous determination of 239Pu + 240Pu and 241Pu in sea-water (Irish Sea, North Sea) and soils (Cumbrian coast, UK; Byelorussia, USSR).
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determination of Plutonium 239 Plutonium 240 and Plutonium 241 in environmental samples using low level liquid scintillation spectrometry
Analyst, 1992Co-Authors: Helge E. Bjørnstad, Brit SalbuAbstract:A radiochemical method for the simultaneous determination of 239Pu + 240Pu and 241Pu in environmental samples has been developed. In the course of the analysis a 236Pu tracer was used for estimating the chemical yield of Plutonium isotopes. After suitable pre-treatment of the sample, the Plutonium nuclides in solution were coprecipitated with iron(III) hydroxide and calcium oxalate and isolated further from impurities and interfering radionuclides by means of anion-exchange chromatography. Plutonium isotopes in the eluate (NH4I-HCI) were converted into nitrate form and then extracted with 20 ml of 5% bis(2-ethylhexyl) hydrogen phosphate extractive cocktail. The final organic solution was measured spectrometrically using an ultra-low-level liquid scintillation spectrometer, Quantulus (LKB, 1220 Wallac). The chemical yields of Plutonium range from 25 to 50% for 100 I of sea-water and 30 to 60% for 40 g of dried soil sample. The counting efficiencies are nearly 100% for 239Pu + 240Pu and 48.8% for 241Pu, respectively. The detection limits were estimated to be 0.20 mBq for 239Pu + 240Pu and 2.2 mBq for 241Pu, respectively. The proposed procedure has been tested for the simultaneous determination of 239Pu + 240Pu and 241Pu in sea-water (Irish Sea, North Sea) and soils (Cumbrian coast, UK; Byelorussia, USSR).
L. W. Green - One of the best experts on this subject based on the ideXlab platform.
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Determination of Plutonium 240/239 ratios in Lake Ontario sediments
Journal of the American Society for Mass Spectrometry, 1991Co-Authors: L. W. Green, F. C. Miller, J. A. Sparling, S. R. JoshiAbstract:A thermal ionization mass spectrometric procedure was developed for determination of 240/239 ratios in subpicogram quantities of Plutonium (Pu), and was applied to Pu extracted from Lake Ontario sediment. The detection limit was ∼ 4 fg of Pu and the precision of 240/239 ratio measurement was ∼ 7% in the 0.07–0.42 pg range. Results of sediment analyses at various depths showed in all cases 240/239 ratios near the mean global fallout value of 0.176 ± 0.014. The lack of variability of the ratios with depth negated the use of Pu, present in excess in the near-surface samples due to leakage from a nearby reprocessing plant, as a geochronological meter. The 240/239 ratio of the leakage Pu appeared to be very similar to that of fallout Pu.
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determination of Plutonium 240 239 ratios in lake ontario sediments
Journal of the American Society for Mass Spectrometry, 1991Co-Authors: L. W. Green, F. C. Miller, J. A. Sparling, S. R. JoshiAbstract:A thermal ionization mass spectrometric procedure was developed for determination of 240/239 ratios in subpicogram quantities of Plutonium (Pu), and was applied to Pu extracted from Lake Ontario sediment. The detection limit was ∼ 4 fg of Pu and the precision of 240/239 ratio measurement was ∼ 7% in the 0.07–0.42 pg range. Results of sediment analyses at various depths showed in all cases 240/239 ratios near the mean global fallout value of 0.176 ± 0.014. The lack of variability of the ratios with depth negated the use of Pu, present in excess in the near-surface samples due to leakage from a nearby reprocessing plant, as a geochronological meter. The 240/239 ratio of the leakage Pu appeared to be very similar to that of fallout Pu.
F. C. Miller - One of the best experts on this subject based on the ideXlab platform.
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Determination of Plutonium 240/239 ratios in Lake Ontario sediments
Journal of the American Society for Mass Spectrometry, 1991Co-Authors: L. W. Green, F. C. Miller, J. A. Sparling, S. R. JoshiAbstract:A thermal ionization mass spectrometric procedure was developed for determination of 240/239 ratios in subpicogram quantities of Plutonium (Pu), and was applied to Pu extracted from Lake Ontario sediment. The detection limit was ∼ 4 fg of Pu and the precision of 240/239 ratio measurement was ∼ 7% in the 0.07–0.42 pg range. Results of sediment analyses at various depths showed in all cases 240/239 ratios near the mean global fallout value of 0.176 ± 0.014. The lack of variability of the ratios with depth negated the use of Pu, present in excess in the near-surface samples due to leakage from a nearby reprocessing plant, as a geochronological meter. The 240/239 ratio of the leakage Pu appeared to be very similar to that of fallout Pu.
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determination of Plutonium 240 239 ratios in lake ontario sediments
Journal of the American Society for Mass Spectrometry, 1991Co-Authors: L. W. Green, F. C. Miller, J. A. Sparling, S. R. JoshiAbstract:A thermal ionization mass spectrometric procedure was developed for determination of 240/239 ratios in subpicogram quantities of Plutonium (Pu), and was applied to Pu extracted from Lake Ontario sediment. The detection limit was ∼ 4 fg of Pu and the precision of 240/239 ratio measurement was ∼ 7% in the 0.07–0.42 pg range. Results of sediment analyses at various depths showed in all cases 240/239 ratios near the mean global fallout value of 0.176 ± 0.014. The lack of variability of the ratios with depth negated the use of Pu, present in excess in the near-surface samples due to leakage from a nearby reprocessing plant, as a geochronological meter. The 240/239 ratio of the leakage Pu appeared to be very similar to that of fallout Pu.
J. A. Sparling - One of the best experts on this subject based on the ideXlab platform.
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Determination of Plutonium 240/239 ratios in Lake Ontario sediments
Journal of the American Society for Mass Spectrometry, 1991Co-Authors: L. W. Green, F. C. Miller, J. A. Sparling, S. R. JoshiAbstract:A thermal ionization mass spectrometric procedure was developed for determination of 240/239 ratios in subpicogram quantities of Plutonium (Pu), and was applied to Pu extracted from Lake Ontario sediment. The detection limit was ∼ 4 fg of Pu and the precision of 240/239 ratio measurement was ∼ 7% in the 0.07–0.42 pg range. Results of sediment analyses at various depths showed in all cases 240/239 ratios near the mean global fallout value of 0.176 ± 0.014. The lack of variability of the ratios with depth negated the use of Pu, present in excess in the near-surface samples due to leakage from a nearby reprocessing plant, as a geochronological meter. The 240/239 ratio of the leakage Pu appeared to be very similar to that of fallout Pu.
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determination of Plutonium 240 239 ratios in lake ontario sediments
Journal of the American Society for Mass Spectrometry, 1991Co-Authors: L. W. Green, F. C. Miller, J. A. Sparling, S. R. JoshiAbstract:A thermal ionization mass spectrometric procedure was developed for determination of 240/239 ratios in subpicogram quantities of Plutonium (Pu), and was applied to Pu extracted from Lake Ontario sediment. The detection limit was ∼ 4 fg of Pu and the precision of 240/239 ratio measurement was ∼ 7% in the 0.07–0.42 pg range. Results of sediment analyses at various depths showed in all cases 240/239 ratios near the mean global fallout value of 0.176 ± 0.014. The lack of variability of the ratios with depth negated the use of Pu, present in excess in the near-surface samples due to leakage from a nearby reprocessing plant, as a geochronological meter. The 240/239 ratio of the leakage Pu appeared to be very similar to that of fallout Pu.