Dosage de radionucléides à vie longue, 93Zr, 93Mo et 94Nb, dans des échantillons issus de l'industrie nucléaire

Un protocole permettant la séparation du zirconium-93, du molybdène-93 et du niobium dans d'échantillons (métaux irradiés/contaminés, effluents) issus de l'industrie nucléaire a été développé. Les techniques séparatives utilisées sont l'extraction liquide-liquide et la chromatographie d'extraction. La mesure de ces radionucléides a nécessité l'obtention de solutions de référence de zirconium-93 et molybdène-93 (actuellement non commercialisées), afin d'étalonner le détecteur de scintillation liquide. Le niobium est mesuré via ses isotopes radioactifs de masse 93m, 94 et 95 qui sont des émetteurs X-bêta-gamma. Les solutions référence de zirconium-93 et molybdène-93 ont des activités massiques respectives de 0,253 0,080 Bq/g 0,195 0,016Bq/mL. Les limites de détection obtenues sont de 10-2Bq/g en Zr-93 et 9,01 10-3Bq/g en Nb-93m en scintillation liquide, 2,9 10-2Bq/mL en Mo-93 en spectrométrie X et 6Bq/g et 45Bq/g respectivement pour les masses 94 et 93m du niobium en spectrométrie gamma.A protocol dedicated to the separation of zirconium-93, molybdenum-93 and niobium-94 contained in complex matrices (irradiated/contaminated metals, effluents) from nuclear industry samples has been developed. The separation steps of this protocol include liquid-liquid extraction and extraction chromatography. The use of the protocol requires reference materials of zirconium-93 and molybdenum-93 (not commercially available) for the calibration of the liquid scintillator counter. Niobium has been measured by gamma spectrometry via its radioisotopes of mass 93m, 94 and 95 which are X-beta-gamma emitters. The reference materials of zirconium-93 and molybdenum-93 present specific activities of 0,253 0,080Bq/g and 0,195 0,016Bq/mL. The detection limits associated are 10-2Bq/g for zirconium-93 and 9,01 10-3Bq/g for niobium-93m by LSC, 2,9 10-2 Bq/mL for molybdenum-93 by X-spectrometry and 6Bq/g and 45Bq/g respectively for the radio-isotopes of mass 94 and 93m of niobium by gamma spectrometry.NANTES-BU Sciences (441092104) / SudocNANTES-ENS Mines (441092314) / SudocSudocFranceF

Electroplating of gallium for the production of gallium 68 for the nuclear medicine at Arronax

International audienc

Electroplating of gallium for the production of gallium 68 for the nuclear medicine at Arronax

International audienc

Determination of radium-226 in aqueous solutions by alpha-spectrometry

International audienceThe new European legislation imposes a lower threshold for radioactivity in drinking water.. This requires the development of more sensitive and reliable analytical methods. This work presents an improved a-spectrometric technique to determine the radium-226 activity in aqueous solution relying on the radium adsorption onto a thin manganese oxide layer followed by a-measurement. The preparation of the MnO2 deposit has been optimized as well as the radium adsorption conditions. Detection threshold and limit of 5 and 10 mBq .L-1, respectively, with a 10% (95% confidence) uncertainty are currently reached. This paper reports on the overall technique and on its application to assess the radium-226 activity in 28 French mineral waters. In addition, the gross alpha- and beta -activities have been evaluated using proportional counting while the uranium concentrations were derived from ICPMS

Electroplating Of Gallium-Nickel Alloy For TheProduction Of Gallium 68 At Arronax

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Extraction behavior of polonium-210 from HCl and HNO3 solution using tributyl phosphate

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Study of the ion exchange selectivity of layered titanosilicate Na-3(Na,H)Ti2O2[Si2O6](2) center dot 2H(2)O, AM-4, for strontium

International audienceThis paper describes for the first time the sorption behaviour of a titanosilicate, AM-4, that exhibits an extremely high affinity for strontium in neutral and alkaline media. The ion exchange selectivity of this layered titanosilicate is explained in relation to the crystalline structure. The simple approach which consists in studying carefully the distribution of formal charges of oxygens in the anionic framework and calculating a normalized bond length in order to measure the ion stability in its site has enabled us to account for the AM-4 performances for the strontium remediation in competition with alkali and alkaline earth metal ions, The Sr uptake amounts as a function of the pH were determined, they can be correlated to the formal charges of Si-O-nbo. The effect of sodium, potassium, calcium and magnesium on the Sr2+ ions sorption was also studied in binary solutions Sr2+/Na+, Sr2+/K+, Sr2+/Ca2+, Sr2+/Mg2+. The determination of the equilibrium constant Sr2+/2Na(+) and of the ion competitive effects with adsorption data have shown that Ca2+ is the most efficient to reduce the uptake of Sr2+. The preliminary Kd values provide an indication that this exchanger may act as a sorber for groundwater and nuclear remediation applications

Extraction behavior of polonium-210 from HCl and HNO3 solution using tributyl phosphate

International audienc

Study of the ion exchange selectivity of layered titanosilicate Na-3(Na,H)Ti2O2[Si2O6](2) center dot 2H(2)O, AM-4, for strontium

International audienceThis paper describes for the first time the sorption behaviour of a titanosilicate, AM-4, that exhibits an extremely high affinity for strontium in neutral and alkaline media. The ion exchange selectivity of this layered titanosilicate is explained in relation to the crystalline structure. The simple approach which consists in studying carefully the distribution of formal charges of oxygens in the anionic framework and calculating a normalized bond length in order to measure the ion stability in its site has enabled us to account for the AM-4 performances for the strontium remediation in competition with alkali and alkaline earth metal ions, The Sr uptake amounts as a function of the pH were determined, they can be correlated to the formal charges of Si-O-nbo. The effect of sodium, potassium, calcium and magnesium on the Sr2+ ions sorption was also studied in binary solutions Sr2+/Na+, Sr2+/K+, Sr2+/Ca2+, Sr2+/Mg2+. The determination of the equilibrium constant Sr2+/2Na(+) and of the ion competitive effects with adsorption data have shown that Ca2+ is the most efficient to reduce the uptake of Sr2+. The preliminary Kd values provide an indication that this exchanger may act as a sorber for groundwater and nuclear remediation applications