共查询到5条相似文献,搜索用时 0 毫秒
1.
S. K. Aggarwal G. Chourasiya R. K. Duggal C. P. Singh A. S. Rawat H. C. Jain 《Fresenius' Journal of Analytical Chemistry》1986,323(2):148-152
Summary A method is described for determining the plutonium concentration by Isotope Dilution Alpha Spectrometry (IDAS) using238Pu as a spike. It involves the addition of a pre-calibrated spike solution to a known aliquot of the plutonium sample solution followed by source preparation using TEG as a spreading agent. The results obtained on a number of samples using this method are compared with those of IDMS using242Pu as a spike as well as with those obtained by IDAS using TTA for purification, with respect to precision and accuracy. Precision of 0.3–0.5% and an accuracy of 0.5% is demonstrated. This method eliminates the need of any separation and purification of plutonium from241 Am and a bulk of other impurities.
Plutoniumbestimmung durch Isotopenverdünnungs-Alpha-Spektrometrie ohne Abtrennung von Americium-241 und anderen Verunreinigungen
Zusammenfassung Bei dem beschriebenen Verfahren der Isotopenverdünnungs-Alpha-Spektrometrie (IDAS) wird238Pu als Spike benutzt. Eine vorgeeichte Spike-Lösung wird zu einem bekannten Aliquot der Probe gegeben und anschließend die Strahlungsquelle unter Verwendung von Tetraethylenglykol als Spreading-Reagens vorbereitet. Die nach diesem Verfahren erhaltenen Ergebnisse werden in bezug auf Präzision und Genauigkeit mit solchen verglichen, die mit Isotopenverdünnungs-Massenspektrometrie unter Verwendung von242Pu als Spike oder mit IDAS unter Verwendung von Thenoyltrifluoraceton zur Reinigung erhalten wurden. Eine Präzision von 0,3–0,5% und eine Genauigkeit von 0,5% wurden erzielt. Durch das beschriebene Verfahren erübrigt sich eine Reinigung des Pu von241Am und anderen Verunreinigungen.相似文献
2.
S. K. Aggarwal G. Chourasiya C. P. Singh A. S. Rawat S. A. Chitambar H. C. Jain 《Journal of Radioanalytical and Nuclear Chemistry》1985,93(3):141-152
A method is described for the determination of plutonium concentration in the presence of a bulk of other impurities by isotope dilution mass spectrometry /IDMS/ using239Pu as a spike. The method involves the addition of239Pu spike / 90 atom%/ to samples with239Pu / 70 atom%/ and vice versa. After ensuring chemical exchange between the sample and the spike isotopes, plutonium is purified by conventional anion exchange procedure in 7M HNO3 medium.239Pu/240Pu atom ratio in the purified spiked sample is determined with high precision /better than 0.1%/ using a thermal ionization mass spectrometer. Concentration of plutonium in the sample is calculated from the changes in239Pu/240Pu atom ratio in the spiked mixture. Results obtained on different plutonium samples using239Pu as a spike are compared with those obtained by the use of242Pu spike. Precision and accuracy comparable to those achieved by using242Pu are demonstrated. The method provides an alternative in the event of non-availability of enriched242Pu or244Pu required in IDMS of plutonium and at the same time, offers certain advantages over the use of242Pu or244Pu spike. 相似文献
3.
Naoki Surugaya Toshiaki Hiyama André Verbruggen Roger Wellum 《Analytical sciences》2008,24(2):247-252
A stable solid spike for the measurement of uranium and plutonium content in nitric acid solutions of spent nuclear fuel by isotope dilution mass spectrometry has been prepared at the European Commission Institute for Reference Materials and Measurements in Belgium. The spike contains about 50 mg of uranium with a 19.838% (235)U enrichment and 2 mg of plutonium with a 97.766% (239)Pu abundance in each individual ampoule. The dried materials were covered with a thin film of cellulose acetate butyrate as a protective organic stabilizer to resist shocks encountered during transportation and to eliminate flaking-off during long-term storage. It was found that the cellulose acetate butyrate has good characteristics, maintaining a thin film for a long time, but readily dissolving on heating with nitric acid solution. The solid spike containing cellulose acetate butyrate was certified as a reference material with certified quantities: (235)U and (239)Pu amounts and uranium and plutonium amount ratios, and was validated by analyzing spent fuel dissolver solutions of the Tokai reprocessing plant in Japan. This paper describes the preparation, certification and validation of the solid spike coated with a cellulose derivative. 相似文献
4.
A field-adapted procedure based on species-specific isotope dilution (SSID) methodology for trace-level determinations of methyl mercury (CH3Hg+) in mire, fresh and sea water samples was developed, validated and applied in a field study. In the field study, mire water samples were filtered, standardised volumetrically with isotopically enriched CH3200Hg+, and frozen on dry ice. The samples were derivatised in the laboratory without further pre-treatment using sodium tetraethyl borate (NaB(C2H5)4) and the ethylated methyl mercury was purge-trapped on Tenax columns. The analyte was thermo-desorbed onto a GC-ICP-MS system for analysis. Investigations preceding field application of the method showed that when using SSID, for all tested matrices, identical results were obtained between samples that were freeze-preserved or analysed unpreserved. For DOC-rich samples (mire water) additional experiments showed no difference in CH3Hg+ concentration between samples that were derivatised without pre-treatment or after liquid extraction. Extractions of samples for matrix–analyte separation prior to derivatisation are therefore not necessary. No formation of CH3Hg+ was observed during sample storage and treatment when spiking samples with 198Hg2+. Total uncertainty budgets for the field application of the method showed that for analyte concentrations higher than 1.5 pg g–1 (as Hg) the relative expanded uncertainty (REU) was approximately 5% and dominated by the uncertainty in the isotope standard concentration. Below 0.5 pg g–1 (as Hg), the REU was >10% and dominated by variations in the field blank. The uncertainty of the method is sufficiently low to accurately determine CH3Hg+ concentrations at trace levels. The detection limit was determined to be 4 fg g–1 (as Hg) based on replicate analyses of laboratory blanks. The described procedure is reliable, considerably faster and simplified compared to non-SSID methods and thereby very suitable for routine applications of CH3Hg+ speciation analysis in a wide range of water samples. 相似文献
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