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A new method for the rapid quantification of neptunium 237 in nuclear effluent was developed. This method is based on the direct measurement of neptunium 237 by ICP-MS/MS in mass-shift mode as NpO and using 20% CO2 as a reaction gas. These measurement conditions allowed the best signal-to-noise ratio at m/z 253 (237Np16O) to be obtained by the efficient elimination of the interferences due to the abundance sensitivity of uranium 238 and hydrides of uranium 235 and uranium 236 while minimizing the elemental fractionation between neptunium and plutonium. Moreover, plutonium 242 can be used as a tracer for neptunium 237 isotopic dilution-based quantification. After an optimization of the measurement parameters, excellent figures of merit were obtained. Indeed, this protocol allows an accurate direct measurement of neptunium 237 in various nuclear effluent samples containing up to 2 mg L-1 (2.4 Bq L-1) of uranium 236 and up to 20 mg L-1 (250 Bq L-1) of uranium 238 with excellent accuracy and uncertainties lower than 15%, for samples containing 10-5 to 10-1 mg L-1 (10-3 to 13 Bq L-1), and a limit of detection for 237Np as low as 4 pg L-1 (10-4 Bq L-1). [ABSTRACT FROM AUTHOR]

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Leaching tests are an important component in assessing the potential of contaminants to leach from waste materials to the environment. Numerous leaching test protocols have been developed for different applications. In this study, we compare four different methods in the context of assessing leaching of inorganic ions from oil sands tailings. The four methods compared were: United States Environmental Protection Agency (EPA) Toxicity Characteristic Leaching Procedure; ASTM D6234; ASTM D3987; and what we refer to as the Deionized method (modified from Syncrude Analytical Aqueous Extraction of Oil Sand Method 1.7). It was found that the EPA Toxicity Characteristic Leaching Procedure generally resulted in the highest ion concentrations. The EPA method had statistically different results for three of the four tailings mixes when compared with the other three leaching methods. For Mo andTi the EPA method always resulted in the lowest concentrations compared with the other methods, and As, T1, and Pb sometimes resulted in the lowest concentrations. The other three leaching protocols resulted in similar dissolved ion concentrations. Key words: leaching, oil sands tailings, ASTM D6234, ASTM D3987, toxicity characteristic leaching procedure (TCLP). Les essais de lixiviation sont un element important de l'evaluation du potentiel de lixiviation des contaminants de dechets dans l'environnement. De nombreux protocoles d'essai de lixiviation ont ete developpes pour differentes applications. Dans cette etude, nous comparons quatre methodes differentes dans le contexte de l'evaluation de la lixiviation des ions inorganiques provenant de residus de sables bitumineux. Les quatre methodes comparees etaient les suivantes : le procede caracteristique de toxicite de lixiviation de << l'Environmental Protection Agency >> (<< EPA >>) des Etats-Unis; la norme de procedure de lixiviation D6234 ASTM; la norme de pratique D3987 ASTM; et ce que nous appelons la methode deionisee (modifiee a partir de la methode 1.7 de l'extraction aqueuse analytique des sables bitumineux de Syncrude). On a constate que le procede caracteristique de toxicite de lixiviation de l'EPA donnait generalement les concentrations d'ions les plus elevees. La methode de l'EPA a donne des resultats statistiquement differents pour trois des quatre melanges de residus miniers comparativement aux trois autres methodes de lixiviation. Pour Mo et Ti, la methode de l'EPA a toujours donne les concentrations les plus faibles comparativement aux autres methodes, et As, Tl et Pb ont parfois donne les concentrations les plus faibles. Les trois autres protocoles de lixiviation ont donne lieu a des concentrations d'ions dissous similaires. [Traduit par la Redaction] Mots-cles : lixiviation, residus de sables bitumineux, norme de procedure de lixiviation D6234 ASTM, norme de pratique D3987 ASTM, procede caracteristique de toxicite de lixiviation (<< TCLP >>)., Introduction In northeastern Alberta, Canada, bitumen is extracted from oil sand deposits. These deposits represent the third largest oil reserves in the world (Alberta 2019). When these deposits occur less [...]

Copyright of Revue de Psychoéducation is the property of La revue canadienne de psycho-education and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

For environmental monitoring and radioecological studies, organic and inorganic 129I is often trapped in active charcoal. The analysis of this radionuclide can be difficult because of the low-level activities involved and its physico-chemical properties (e.g., volatility and multiple oxidation degrees). This study proposes a new method for 129I analysis by ICP-MS/MS, which consists in the extraction of iodine from charcoal by acid digestion followed by purification using a commercial specific resin. This new method allows reaching environmental levels of gaseous 129I near the fuel reprocessing plant of La Hague (France) with a limit of detection of only 2 mBq sample−1. [ABSTRACT FROM AUTHOR]