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To provide reliable K d data for Cs required for the performance assessment of cement-based radioactive waste repositories, two complementary approaches were followed. First, Cs sorption was determined on a range of hydrated cement paste (HCP) and mortar samples of CEM I and CEM V for different degradation states and solution …
In fact, Portland cement exhibits weak adsorption of cesium. Konstantin Volchek's study (Volchek et al., 2011) demonstrates that, under optimal conditions with an initial concentration of 10 mg‧L −1, the adsorption capacity of cement blocks for …
Cesium-137 is a common radioactive byproduct found in nuclear spent fuel. Given its 30 year half life, its interactions with potential storage materials-such as cement paste-is of crucial importance. In this paper, simulations are used to establish the interaction of calcium silicate hydrates (C-S-H)-the mam binding phase of cement paste-with ...
In this report adsorption behaviors of cement pastes toward iodine (as anion) and cesium (as cation) were studied. Adsorption of iodine was remarkable for OPC and MHP pastes that are known to have high molar ratio CaO/SiO{sub 2}, partition coefficient being 100 ml/g for initial tracer concentration of 10{sup -5} mol/l.
Cesium-137 is a common radioactive byproduct found in nuclear spent fuel. Given its 30 year half life, its interactions with potential storage materials—such as cement paste—is of crucial importance. In this paper, simulations are used to establish the interaction of calcium silicate hydrates (C-S-H)—the main binding phase of cement paste ...
Experiments were carried out in a range of initial cesium concentrations from 0.0103 to 10.88 mg L (-1) and temperatures from 278 to 313 K using coupons of cement mortar immersed in the solutions ...
The leach behavior of cesium from a series of cement-based waste forms has been modeled in terms of pore solution concentration and phase formation data. Cement-based Materials enriched in alumina … Expand. 34. Save. Immobilization of cesium in alkaline activated fly ash matrix.
ABSTRACT Recently, extremely high dose rates were detected in the three-layer concrete plugs of the units 2 and 3 at the Fukushima Daiichi Nuclear Power Plant. The high dose rates suggest that there are some trapping effects of radioactive materials on shield plugs when gas species and aerosols (e.g. CsOH and CsI) are released from the …
As Kd from radwaste elements in concrete systems show a wide range of values, a modelling of cesium and lead immobilization in Calcium Silicate Hydrate (CSH, …
The cement cured at 50 degrees C and 30.3 MPa exhibited a shallower depth of degradation and displayed a well-defined carbonated zone as compared to cement cured under ambient conditions, likely due to smaller, more evenly distributed Ca(OH)2(s) crystals that provide a uniform and effective barrier to CO2 attack. Expand
Cesium-137 is a common radioactive byproduct found in nuclear spent fuel. Given its 30 year half life, its interactions with potential storage materials—such as cement paste—is of crucial importance. In this paper, simulations are used to establish the interaction of calcium silicate hydrates (C-S-H)—the main binding phase of cement …
DOI: 10.1016/j.jenvrad.2023.107350. Abstract. In this study, microstructural differences and changes in the adsorption capacity of cesium between cement and carbonated cement …
In this study, microstructural differences and changes in the adsorption capacity of cesium between cement and carbonated cement were investigated. Cement blocks were ground to powder for rapid carbonation, and microscopic variations were characterized by XRF, XRD, FT-IR, SEM, BET, and TGA.The characterization results …
The adsorption of cesium from aqueous solutions on cement mortar was investigated in the range of initial cesium concentrations of 0.0103–10.88 mg L −1 and in the range of temperatures of 278–313 K. It took approximately 12 …
DOI: 10.1016/j.chemosphere.2020.127494 Corpus ID: 224886330; Adsorption characteristics of cesium onto calcium-silicate-hydrate in concrete powder and block @article{Kang2020AdsorptionCO, title={Adsorption characteristics of cesium onto calcium-silicate-hydrate in concrete powder and block}, author={Seunghee Kang and Jeshin Lee …
Sort. Sort by citations Sort by year Sort by title. Cited by. Cited by. Year; Thermodynamics, kinetics, and mechanics of cesium sorption in cement paste: A multiscale assessment. J Arayro, A Dufresne, T Zhou, K Ioannidou, JF Ulm, R Pellenq, LK Béland. Physical Review Materials 2 (5), 053608, 2018. 26:
This suggests that for contaminated concrete waste and demolition debris, the cesium residing in the cement phases would be largely leachable in fresh or salty waters. Moreover, cesium found on the aggregate phases would be leachable, although to a much lesser extent. 3.6.2. Ammonium-based wash solutions
As Kd from radwaste elements in concrete systems show a wide range of values, a modelling of cesium and lead immobilization in Calcium Silicate Hydrate (CSH, xCaO.SiO 2.H 2 O, with 0.7 (aged cements)
Cement-based materials are widely used for stabilizing and conditioning radioactive waste in low- and intermediate-level repositories. In this study, the adequacy of four different types of mortars, obtained from four different commercial cements, CEM I, II and IV (A and B), to act as barrier to 137 Cs migration was analysed. Diffusion …
Rock physics represents the link between geologic reservoir parameters (e.g., porosity, clay content, sorting, lithology, saturation) and seismic properties (e.g., V P /V S, density, elastic moduli).Rock physics models can either be used to interpret observed sonic and seismic velocities in terms of reservoir parameters, or they can be used to …
The relationship between the fraction leached and the ratio of surface area and volume (S/V) of a specimen has been studied in order to evaluate the safety of a cement composite for disposal. The leaching fraction of radionuclides was measured for the different S/V ratios. In a case of either 137Cs, 90Sr or 60Co, the amount leached is directly …
The leaching rate of cesium has been studied in cement. The solidification matrix was a standard Portland cement with increased sulphate resisting properties mixed with 300 kg/m 3 or 350 kg/m 3 powdered ion exchange resins, and with or without 5 weight-% zeolite added to the grout. The leaching rates from an ordinary cement matrix and a …
Learn how cesium-137 interacts with cement paste, a potential storage material for nuclear waste, using simulations and atomistic models.
Diffusion and sorption in cementitious materials are important factors influencing radionuclide migration in radioactive waste disposal. Four different experimental techniques have been used to study these processes for Cs +, Sr 2+, and I − ions in Sulphate Resisting Portland Cement paste saturated with water. The results of different ...
Thermodynamics, kinetics, and mechanics of cesium sorption in cement paste: A multiscale assessment. Jack Arayro, Alice Dufresne, Tingtao Zhou, Katerina …
DOI: 10.1016/J.JHAZMAT.2005.12.020 Corpus ID: 815168; Immobilization of cesium and strontium radionuclides in zeolite-cement blends. @article{Elkamash2006ImmobilizationOC, title={Immobilization of cesium and strontium radionuclides in zeolite-cement blends.}, author={Ahmed Mohamed El-kamash and …
The naturally occurring mineral zeolites containing mordenite and clinoptilolite (Zeolite I), which have high atom ratios of silicon and aluminum, possess an extremely high effectiveness for immobilizing 137Cs in a cement matrix. Abstract-The reduction of cesium leachability by addition of mineral zeolites to enhance the safety of solidification of …
DOI: 10.1016/j.jhazmat.2019.121180 Corpus ID: 202883394; Cesium retention and release from sulfur polymer concrete matrix under normal and accidental conditions. @article{Szajerski2020CesiumRA, title={Cesium retention and release from sulfur polymer concrete matrix under normal and accidental conditions.}, author={Piotr Szajerski and …
Sorption of cesium onto the mineral phases and cement of concrete and desorption into simple salt solutions. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY. Elsevier Science Ltd, New York, NY, USA, 165-171, (2016). Access & Use Information. Public: This dataset is intended for public access and use.
To assess the safety of disposal of radioactive waste material in cement, curing conditions and time of leaching radionuclides 137Cs have been studied. Leaching tests in cement-ion exchange … Expand
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