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Abstract  

Following up transfer of strontium from soil to plants requires determination of isotope in the surface layer of soil and a chosen plant. The most endangered food products are plants including commonly grown grain, which constitutes a basic feeding component for both people and animals. Indeed large amounts of 137Cs, 90Sr get into organisms of people and animals with the food, therefore determination of radioactivity of elements in food products and animal fodder is very essential. Choice of proper diet allows to limit the level of human organism denaturation. The aim of this paper was to study relocation of 90Sr, 137Cs, 40K isotopes from soil to grain and then from grain to food products. There were investigated soil, wheat, barley, groats, flour, macaroni and breakfast flakes. Based on the obtained results there were calculated effective weighted doses [nSv] from consumption of 1 kg of a product for different age groups.

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Abstract  

Early determination of 89Sr and 90Sr in radiological emergency is hampered by the presence of interfering short-lived fission products. In this study, three commonly used radioanalytical strategies for 89Sr and 90Sr were evaluated theoretically considering their suitability in a nuclear explosion scenario. The methods were evaluated with respect to the need for decay time of interfering short-lived strontium and yttrium isotopes, and reduction of other known interfering nuclides prior to measurement. The strategy shown to be most successful included initial separation of strontium and determination of 89Sr, followed by an yttrium separation and counting of 90Y. 89Sr and 90Sr could be determined about 5 and 9 days after a nuclear explosion, respectively.

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Abstract  

In this work a method for the determination of both 89Sr and 90Sr is presented. The method can potentially be used in radiological emergency and deliver results shortly after an incident. The method development was based on theoretical calculations of potential interferences from other fission products and how these could be discriminated when applying different chemical separation schemes. Validation was done on reactor coolant water containing short-lived fission products, and on a reference material. The results indicate that correct results of 89Sr and 90Sr can be obtained 4 and 9 days, respectively, after an incident.

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Abstract  

This work describes a procedure for the isolation of 90Sr and 210Pb from deer bones by anion exchange methods and their sequential measurement by LSC. To prevent collection of Pb on the Sr·Spec® resin we first separated Pb on a Dowex anion exchange column. Sr, which is not held back on the Dowex column, was then purified using Sr·Spec® resin: first Ca and the Ra isotopes were eluted with 3 M HNO3 and then Sr was eluted with distilled water. With this 2-steps procedure pure 210Pb and 90Sr spectra can be achieved. The chemical yield of both steps was determined by ICP-MS. Our 90Sr results show satisfying agreement with data obtained by a shorter Sr·Spec® method and also by the “classical” 90Sr determination using fuming nitric acid. Also 210Pb results were checked by re-measuring bone samples with already known 210Pb activities. Further our method was verified on the reference sample IAEA-A-12.

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Abstract  

A new inorganic material, sodium titaniumsilicate has been synthesized, and characterized by physicochemical and spectroscopic tools. The thermal and radiation stability of the compound was checked by TGA technique and a γ-irradiating chamber with a total dose rate of 5 kGy/h. The compound is highly stable towards thermal, chemical and total radiation dose of 64 kGy. The study of the exchange capacity of the material towards different alkali and alkaline earth metal ions showed that the sorption capacities of the alkali metal ions were greater than those of alkaline earth metal ions. The crystalline state of this new inorganic material is very useful as an inorganic ion exchanger to have the carrier free short-lived β-active daughter product 90Y from the long-lived 90Sr of the radioactive equilibrium mixture. The absorbed daughter was recovered by using 1.0% EDTA solutions at pH 7.0 as eluting agent. The features and trends in elution are encouraging to apply this material as an exchanger in radionuclide generator system.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: G. Manjón, F. El-Daoushy, and R. García-Tenorio

Abstract  

For a better understanding of the behaviour of90Sr in aquatic systems, this -emitter has been determined in the different layers of a lake sediment core which has been previously dated using the well established210Pb dating method. For this, a radiochemical technique has been developed for the isolation of strontium from the sediment samples and for its activity measurement with a low-level gas-flow proportional counter. A conservative behaviour of90Sr in the water column remaining dissolved in the water body, can be inferred from the data obtained. Consequently, a possible90Sr transport pathway through the outflowing waters of the lake can be deduced.

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Abstract  

The Intercomparison Studies Program (ISP) at the Oak Ridge National Laboratory (ORNL, Oak Ridge, TN USA) provides natural-matrix human urine quality-assurance/quality-control (QA/QC) samples to radiobioassay analysis laboratories. Samples are provided to these laboratories as “single-blind” or “double-blind” unknowns, spiked with radioactive-solution standards at “low” levels (e.g., 0.7–7 Bq g−1 for 3H and 0.7–7 Bq kg−1 for 90Sr). Participants use the results as a tool for self-evaluation and a measure of performance. In this paper, sample preparation and the results of testing during the years 2001–2005 for 3H and 90Sr are presented and discussed.

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Abstract  

In this research, for the first time Nb and Ge were doped into titanosilicate nanoparticles up to 25% simultaneously. Crystalline phases and morphology of the synthesized samples were studied by X-ray diffraction (XRD) method and scanning electron microscope (SEM), respectively. Elemental analysis of the samples was performed using X-ray fluorescence (XRF) and Energy dispersive X-ray (EDX) techniques. Surface area of the samples was measured by BET method. Ion exchange potential of the synthesized samples for Sr2+ and Cs+ and effective parameters such as concentration, temperature, time, and pH were investigated. In addition,137Cs and 90Sr radio nuclides absorption in the best appropriate sample was examined. The selectivity of the samples for absorption of 137Cs and 90Sr was studied by gamma spectroscopy, liquid scintillation spectrometry, and atomic absorption spectroscopy methods. The obtained results showed that the prepared samples had good potential for absorption of 137Cs and 90Sr from the model solution. The sample containing equal amount of niobium and germanium, removed completely the 137Cs within the waste water of Tehran nuclear reactor and 90Sr in the desired solution.

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Abstract  

A method is described for the determination of 90Sr in environmental samples using combination of developed in-house method, Eichrom Sr resin and Beta Counter. Strontium was efficiently, rapidly and simply separated from Ca and other interfering matrix components by Eichrom Sr resin. All the results in general showed good accuracy, high precision, reliable and in good agreement between these two measured and certified value of SRM (i.e. IAEA-375, IAEA-326, IAEA-152 and IAEA-414). As a whole, the procedure described in this work notably improves conventional methods in particular concerning the time needed, sample volume, safer and others. Thus, the introduced method was successfully performed and will be applied to actual sample for the determination of 90Sr in different environmental materials such as soil, sediments, milk, biological sample, water etc.

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Abstract  

The Nuclear and Technological Institute (ITN) has the legal responsibility to carry out the environmental radiological monitoring at a national level. This survey was planned to provide relevant information on radioactivity levels in different components of the ecosystem. In what concerns the terrestrial environment the evaluation of the 90Sr activity concentrations in foodstuffs has been performed using a method based on the separation of 90Sr by extraction chromatography and beta determination by liquid scintillation counting (LSC) technique. The trials were carried out using 7 g of ash samples and 3 g of commercial Sr-resin (Eichrom). Validation trials were also performed using 90Sr spiked samples. The chemical yields were determined by gravimetric method, after the addition of stable strontium to the foodstuffs. The 90Sr activity concentrations in complete meals, meat and vegetables were determined after 90Y ingrowths in the region 12–862 keV, using the Tri-Carb 3170 TR/SL scintillation counter in normal mode and a counting time of 120 min. The results obtained were low and of the same order of magnitude of those reported by other European countries.

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