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Made available in DSpace on 2014-10-09T12:34:17Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:10:01Z (GMT). No. of bitstreams: 0 / O IPEN/CNEN-SP fabrica combustíveis para uso no seu reator nuclear de pesquisas, o IEA-R1. Para qualificar os seus combustíveis tem que comprovar o bom desempenho destes sob irradiação. Como o Brasil não possui reator nuclear de pesquisa com altos fluxos de nêutrons ou células quentes apropriadas para a realização de exames pós-irradiação de combustíveis nucleares, o IPEN/CNEN-SP conduziu um programa de qualificação operacional de elementos combustíveis empregando compostos de urânio já internacionalmente testados sob irradiação e qualificados para uso em reatores de pesquisas, obtendo experiência nas etapas de desenvolvimento tecnológico de fabricação de placas combustíveis, irradiação e ensaios não destrutivos pós-irradiação. Foram fabricados e irradiados diretamente no núcleo do IEA-R1, com sucesso, elementos combustíveis contendo dispersões com baixas frações volumétricas de combustível. Entretanto, existem planos no IPEN/CNEN-SP para aumentar a densidade de urânio dos seus combustíveis. O objetivo deste trabalho de tese consistiu no estudo e proposição de aplicação de um conjunto de métodos não destrutivos para a qualificação dos combustíveis a dispersão de U3O8-Al e U3Si2-Al com alta densidade de urânio fabricados no IPEN/CNEN-SP. Para tanto, foram considerados os recursos de irradiação e a aplicação, na piscina do reator IEA-R1, de métodos não destrutivos disponíveis na Instituição. A proposta consiste em especificar, fabricar e irradiar miniplacas combustíveis, nas densidades máximas já qualificadas internacionalmente e efetuar acompanhamento das condições gerais das mesmas, ao longo do período de irradiação, por meio de métodos não destrutivos na piscina do reator. Além dos métodos de inspeção visual e de sipping já empregados na Instituição, foi concluída a infraestrutura para realização de ensaios dimensionais sub-aquáticos para a avaliação do inchamento das miniplacas combustíveis irradiadas. As análises dos resultados darão subsídios para avaliar e decidir a continuidade ou não das irradiações das miniplacas, até que sejam alcançadas as queimas estipuladas para os testes de irradiação no IEA-R1. / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

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Ligas de Urânio são candidatas ao uso como combustível nuclear em reatores avançados, dentre essas ligas se destacam as ligas de Urânio com Nióbio e com Zircônio. Este trabalho investigou como os teores de Nb e Zr, assim como a processamento termomecânico afetam as microestruturas e as propriedades mecânicas de 3 ligas U-XNb-YZr onde X+Y=12. Duas amostras contendo 50g cada, foram fabricadas através de fusão à plasma nos teores U-3Nb-9Zr (liga 39), U- 6Nb-6Zr (liga 66) e U-9Nb-3Zr (liga 93). Uma das amostras de cada liga foi tratada termicamente por 5h a 1000°C para a realização de homogeneização química. A amostra homogeneizada e a amostra bruta de fusão de cada liga foram conjuntamente encapsuladas em aço para a realização de laminação a quente seguida de um recozimento final a 1000°C por 2h. À rota adotada pela amostra bruta de fusão chamou-se \" Rota C\" e a rota adotada pela amostra homogeneizada chamou-se \"Rota H\". A caracterização microestrutural foi feita por microscopia óptica e eletrônica de varredura. Todas as amostras, independente do processamento, apresentaram precipitados ricos em Nióbio e Zircônio em adição a uma matriz rica em Urânio. A caracterização das amostras brutas de fusão mostra que os teores de elementos de liga influenciam diretamente a morfologia das dendritas evidentes na microestrutura assim como das demais fases presentes em cada amostra. A liga 39 apresentou predominantemente fase ?\', a liga 66 a fase ?\" com traços de fase y e a liga 93 a fase y com traços de fase ?\". Após o tratamento térmico de homogeneização, a liga 39 apresentou fase ?\" na forma celular enquanto a liga 66 apresentou as fases y0 e y e a liga 93 apresentou apenas fase y. As propriedades mecânicas das ligas foram avaliadas por ensaios de dureza e de dobramento simples. As amostras da Rota C apresentaram redução de dureza em relação à condição inicial. Todas as microestruturas das amostras laminadas a quente exibiram duas fases ricas em U. A liga 39 apresentou as fases ?\" na forma celular e ?\' após a laminação a quente. Após o recozimento final na rota C, a liga 39 apresentou fase ?\" na forma acicular enquanto as ligas 66 e 93 apresentaram as fases ?\" e y após a laminação e fase y. A fração de área da amostra pobre em U elevou-se nas ligas 39 e 66 e reduziu-se na liga 93. As amostras da Rota H apresentaram redução de dureza em relação à condição bruta de fusão. A liga 39 apresentou fase ?\" na forma celular com orientação e traços da fase ?, a liga 66 exibiu as fases y0 e y e a liga 93 as fases y e y0. Após o recozimento final, a liga 39 mostrou-se novamente na forma ?\" na forma celular, mas sem orientação. A liga 66 apresentou fase y e a liga 93 fase y0. Os testes de dobramento simples mostraram que as ligas da Rota C exibem plasticidade, retendo parte da deformação plástica após a ruptura das amostras testadas. Já as amostras da Rota H mostraram comportamento super elástico, possibilitando maiores deformações mas sem reter deformação plástica após a ruptura das amostras. A melhor relação entre deformação total e residual foi observada na liga 93 fabricada pela Rota C. As análises nos perfis de fratura das amostras da Rota C mostram fraturas transgranulares em todas as amostras. O perfil de fratura de na amostra recozida liga 39 mostra que a fase ?\" na forma acicular tende a deforma-se por deslizamento. As análises dos perfis de fratura nas amostras da Rota H confirmaram a ausência de deformação plástica mesmo em escala microscópica. Para essa condição, a fase ?\" na forma celular com orientação (liga 39) aparenta deformar-se por maclação. As análises de superfície de fratura indicam que a fase pobre em U tem participação durante o processo de crescimento e propagação da fratura na Rota H, atuando como caminho para bifurcação de trincas acelerando o processo de ruptura, enquanto na Rota C, a fase pobre em U deforma-se conjuntamente com a matriz de U. Em uma segunda etapa do trabalho, a estabilidade das microestruturas resultantes na amostras processadas foi investigada por Ensaios de Calorimetria Diferencial Exploratória (DSC) e por calorimetria de queda livre (esta apenas para a amostra 93 da rota H). O teor de Nb e Zr também afeta a estabilidade das fases presentes em cada amostra. foram realizados com as amostras da condição homogeneizada e laminada. A quantidade de transformações assim como o estado final de cada liga diferiu de acordo com a razão Nb/Zr. Após o ciclo de aquecimento e resfriamento da análise térmica, a liga 39 apresentou fase ?\', a liga 66 fase ?\" e a liga 93 fase y. No ensaio de calorimetria por queda livre foi possível observar as diferentes etapas de reação de envelhecimento da matriz g, correspondendo a à transformação y -> y0 (entre 525 e 530 K), a transformação y -> ?\". (entre 623 e 651 K) e à transformação y\' -> y3+? (entre 825 e 925 K). / Uranium alloys are candidates to be used as nuclear fuel in research reactors, among the U alloys, the Nb and Zr containing alloys are promising. This work evaluated how the Nb and Zr content and the thermomechanical processing affects the microstructure and mechanical properties of 3 alloys U-XNb-YZr were X+Y=12. Two 50g slugs of each sample were fabricated using plasma arc melting according to U-3Nb-9Zr (alloy 39), U-6Nb-6Zr (alloy 66) and U-9Nb-3Zr (alloy 93). One slug of each alloy was heat treated for 5h at 1000°C to perform the chemical homogenization. The homogenized sample and the as-cast one were encapsulated in the same steel frame in order to perform hot rolling. After the rolling process, the samples were annealed by 2h at 1000°C. The route that uses only as-cast samples was nominated \"Route C\" and the route that uses the homogenized sample was nominated \"Route H\". The microstructural characterization was performed by optical and scanning electron microscopy. All samples, regardless the processing route, presented Nb and Zr rich precipitates in addition to U rich matrix. The characterization of as-cast samples shows that the content of the alloying element has a direct influence on dendrite morphology as in the phases presented for each alloy. The alloy 39 presented predominantly ?\' phase, the alloy 66 the ?\" phase with a small quantity of ? phase and the alloy 93 presented the ? phase with small quantity of ?\" phase. Afte the homogenization, the alloy 39 presented cellular ?\" phase, the alloy 66 presented ?0 and ?, the alloy 93 presented only ? phase. The mechanical properties were evaluated by hardness measurements and free bending tests. The Route C samples presented hardness reduction in comparison to the initial condition. All microstructures of hot-rolled samples of this route exhibit two U rich phases. The alloy 39 exhibited cellular ?\" and ?\', after the final annealing the alloy 39 presented acicular ?\". The alloys 66 and 93 exhibited ?+?\" after hot rolling and ? phase after the final annealing. The area fraction of poor U phase increased in the alloys 39 and 66, but reduced in alloy 93. The Route H samples presented hardness reduction in comparison to as-cast samples. The alloy 39 presented cellular oriented ?\" phase and a small quantity of ? phase. The alloy 66 exhibited ?0 and ?, the alloy 93 ? and ?0. After the final annealing, the alloy 39 presented the ?\" again, but without orientation. The alloy 66 presented ? phase and the alloy 93 presented ?0. The free bending tests show that Route C samples have real plasticity, retaining part of deformation after rupturing as plastic strain. The Route H samples exhibited superelastic behavior, allowing higher deformations but retaining no plastic strain after sample breaking. The better balance between total and residual strain was observed in alloy 93 fabricated by Route C. The cracking profile analysis of Route C samples shows transgranular fractures in all samples. The Cracking profile of final 39 sample shows that acicular ?\" tends to deform by slipping. The cracking profile analysis of Route H samples confirmed the absence of plasticity even on the microscopic scale. This condition, the oriented cellular ?\" phase (alloy 39) apparently deforms by twinning. The crack surface analysis indicates that the U poor phase has a direct participation in crack growing and propagation, acting as forking points to the fracture and accelerating the fracture process. In the Route C samples, the poor U phase deforms alongside the U matrix. The stability of resulting microstructures of homogenized and hot rolled samples was investigated by Differential Scanning Calorimetry (DSC) and Drop Differential Scanning Calorimetry (only for the homogenized hot rolled 93 sample). The Nb and Zr also affect the stability of present phases in each sample. The number of transformations and the final structure is directly influenced by the Nb/Zr ratio. After the thermal cycle imposed by the DSC analysis, the alloy 39 exhibited ?\' phase, the alloy 66 exhibited ?\" phase and the alloy 93 exhibited ? phase. The Drop-DSC allowed observing the different stages of reaction in ? matrix, corresponding to ? -> ?0 (between 525 and 530 K), ? -> ?\" transformation (between 623 and 651 K) and ?\' -> ?3+? transformation (between 825 and 925 K).

Low level nuclear waste arising from UK nuclear sites, research establishments, hospitals and industry is currently disposed of at the Drigg Disposal Facility in Cumbria. Waste is packed into steel canisters before being compacted and grouted into larger steel storage containers. The aqueous chemistry of wastes, especially radionuclides, in the presence of grout material is of major interest. The gout used at the Drigg site is a mixture of Ordinary Portland Cement and Pulverised Fly Ash additive, from which ingressing water will leach high levels of calcium, sodium and potassium and produce waters of a high pH. Aerobic environments are expected to dominate over the early period of the vault life, after which the combined effect of canister corrosion and microbial activity will lead to anaerobic conditions. After a much longer period (100,000 years) anaerobic conditions may cease and yield once again an aerobic environment where migration of radionuclides may be sorption-controlled rather than on hydroxide precipitation at high pH. Work has been performed under both aerobic and anaerobic conditions to study uranium solubility in the presence of complexing ligands that may be present in the waters of the nearfield of a low-level waste disposal vault. Eleven ligands have been investigated: carbonate, phosphate, chloride, sulphate, acetate, citrate, EDTA, NTA and organic matter- humic acid, fulvic acid and iso-sacchannic acid. Anaerobic conditions were achieved by two different procedures; the first used ferrous ions in hydroxide solution and the second used dithionite in hydroxide solution. Both methods produce reducing electrode potentials and high pH. Computer software has been used to model experimental results, thereby predicting uranium solubilities and speciation, and to propose new formation constants to fit the experimental results more closely. Studies have also been perforined to measure uranium sorption by grout material at high pH in the presence of the above ligands. This work makes a significant contribution to the understanding of uranium solubility and speciation in waters. at high pH and under conditions relevant to low level nuclear waste disposal.

Le recyclage des actinides mineurs produits en réacteur nucléaire est un point clé pour les cycles du combustible du futur. Différentes options sont ainsi envisagées : leur réintégration au sein d'un nouveau combustible « refabriqué » ou leur transmutation dans le but de réduire significativement la radiotoxicité des déchets ultimes. Dans ces deux cas de figure, la synthèse de matériaux innovants intégrant les actinides mineurs de manière homogène est nécessaire.En ce sens, les voies sol-gel présentent des avantages certains par rapport aux autres voies de synthèse (co-précipitation, métallurgie des poudres) tels que l'organisation du matériau à l'échelle colloïdale ou la création de porosité de manière contrôlée grâce à l'utilisation d'un « template ». De plus, la possibilité de travailler en milieu humide, de la solution précurseur au matériau final, permet d'éviter la formation de poudres pulvérulentes et contaminantes, point essentiel dans le cas de matériaux incorporant des éléments radioactifs. Cette thèse vise à démontrer l'adaptabilité de ce type de procédé au domaine du nucléaire. Dans un premier temps, une méthodologie de synthèse par voie sol-gel colloïdale et de caractérisation sur un système non-actif à base de zirconium a été mise en place et a permis la compréhension des mécanismes mis en jeu au cours de cette synthèse. Suite à cela, des études de mise en forme, et notamment d'insertion de porosité, ont été réalisées. Des monolithes de zircone ont de cette manière pu être obtenus grâce au couplage entre le procédé sol-gel colloïdal et la formation d'une émulsion stabilisée par des clusters de particules solides.Finalement, une transposition de ces travaux sur un système à base d'uranium a été initiée, soulevant différentes perspectives prometteuses concernant les possibilités de mise en forme du matériau final. / One of the main objectives for the future nuclear fuel cycle is the recycling of the minor actinides. Different options are considered: their integration into a new fuel for a prospect of a closed fuel cycle or their transmutation in order to significantly decrease the long-term radiotoxicity of ultimate wastes. In both cases, the synthesis of new advanced materials integrating the actinides jointly is required.Sol-gel processes allow the organization of the material at the colloidal scale or the insertion of controlled porosity using « templates ». Furthermore, the possibility to work in a « wet environment » prevents the formation of pulverulent powders which are contaminant in the case of materials incorporating radioactive elements. The main purpose of this work is to demonstrate the adaptability of this route to the nuclear field.Firstly, a methodology of synthesis from a colloidal sol-gel route was set up on a non-radioactive zirconium-based system in order to characterize and understand of the different mechanisms of this synthesis. Then, studies on shaping, including insertion of porosity, were performed. Zirconia monoliths have been obtained thanks to a coupling between a colloidal sol-gel process and the formation of an emulsion stabilized by clusters of solid particles. Finally, a transposition of this work to an uranium-based system was introduced, pointing out different promising perspectives specially concerning the possibilities of shaping of the final material.

L’étude de la chimie des actinides est essentielle dans le cadre de la technologie nucléaire pour le développement de nouveaux combustibles, pour l’étude du retraitement des déchets nucléaires et la migration des actinides dans l’environnement mais aussi pour la compréhension fondamentale des interactions actinide/ligand et la formation de liaisons multiples. Les propriétés magnétiques des molécules polymétalliques d’actinides sont particulièrement intéressantes pour explorer la communication magnétique entre différents centres métalliques. De plus, ces molécules ont été identifiées comme particulièrement prometteuses pour la conception de molécules aimants. L’uranium a une grande réactivité redox notamment due à ses multiples degrés d’oxydation accessibles et forme aisément des assemblages polynucléaires. Néanmoins, très peu de synthèses contrôlées de complexes polymétalliques d’uranium et de neptunium ont été décrites dans la littérature. La première approche de ce travail repose sur la synthèse de clusters oxo/hydroxo d’uranium à partir de l’hydrolyse contrôlée d’uranium tétravalent en présence d’un ligand organique rencontré dans l’environnement. Cette étude a mené à une famille de clusters aux topologies originales, dont la taille varie en fonction des conditions réactionnelles employées. Cependant les clusters obtenus ne mènjavascript:nouvelleZone('abstract');_ajtAbstract('abstract');ent pas à des propriétés de molécules aimants. Dans le but de favoriser une plus grande interaction entre les métaux par le ligand pontant, l’interaction cation-cation a été utilisée pour la synthèse rationnelle d’assemblages d’uranyle(V). Par le passé, peu de complexes d’uranyle(V) ont été isolés à cause de son instabilité vis-à-vis de la dismutation ; cependant, l’optimisation du ligand organique et des conditions de synthèse ont finalement permis de stabiliser l’uranyle(V). Nous avons utilisé des complexes stables d’uranyle(V) comme brique de base pour former des molécules hétéronucléaires avec des métaux 3d et 4f. Un réglage fin des conditions de réactions a mené à une conception rationnelle d’assemblages discrets ou polymériques. L’étude des propriétés magnétiques de ces assemblages d’uranium a mis en valeur des propriétés de molécules ou chaînes aimants avec de hautes valeurs d’énergie de relaxation. L’uranyle(V) a également été utilisé comme modèle structural du neptunium qui est plus radioactif permettant d’isoler un complexe isostructural homométallique de neptunyle(V) grâce à des conditions réactionnelles similaires. Finalement, des ligands nitrures favorisant la formation de liaison multiples uranium-ligand, ont été utilisés pour construire de nouveaux complexes binucléaires d’ujavascript:nouvelleZone('abstract');_ajtAbstract('abstract');ranium supportés par des ligands silanols. De nouvelles molécules, sans précédent, contenant des nitrures comme ligand pontant associés à de l’uranium au degré d’oxydation +III ont été isolées et caractérisées. / The study of actinide chemistry is not only essential for the development of nuclear fuel, nuclear fuel reprocessing or environmental clean up, but also for the understanding of fundamental actinide/ligand interactions and multiple bounding. The magnetic properties of polynuclear actinide molecules are of significant interest to investigate the magnetic communication between the metallic centres. Furthermore, they are highly promising for the design of molecular magnets. Uranium undergoes redox reactions due to a wide range of available oxidation states and easily forms polynuclear assemblies. However, only a few controlled synthetic routes towards these polynuclear uranium assemblies are described in the literature. In this context, the first part of this work was dedicated to the synthesis of oxo/hydroxo uranium clusters from the controlled hydrolysis of tetravalent uranium in the presence of an environmentally relevant ligand. This led to the synthesis of clusters with novel topologies, for which size could be varied as a function of the reaction conditions employed. However, the obtained clusters do not behave as SMM. In order to gain a stronger interaction between metallic centres, the cation-cation interaction was used to rationally design polynuclear uranyl(V) complexes. The isolation of uranyl(V) complexes had been limited in the past by its disproportionation, however, a fine tuning of the organic ligand and reaction conditions finally allowed to stabilise uranyl(V). We used stable uranyl(V) units as building block to form heteronuclear complexes with 3d and 4f metals with polymeric or discrete structures. The study of the magnetic properties of the uranium polynuclear assemblies was carried out and revealed single molecule or chain magnet behaviours with high energy barriers. The uranyl(V) unit was also used as a structural model for the more radioactive neptunium element, allowing the isolation of an isostructural trinuclear neptunyl(V) assembly in similar reaction conditions. Finally, the use of a nitride ligand as a bridging unit, allowing the formation of uranium-ligand multiple bonds, was explored to build novel di-uranium complexes supported by siloxy ligands. Nitride molecules containing unprecedented uranium in the +III oxidation state were isolated and characterised.

Les isotopes d’américium représentent une part importante des déchets nucléaires à haute activité et à durée de vie longue dans le combustible usé. Parmi les options de retraitement envisagées, sa transmutation en réacteurs à neutrons rapides au sein de pastilles d’oxydes mixtes d’uranium-américium de composition U1-xAmxO2±δ est une option prometteuse qui permettrait de diminuer l’empreinte écologique des sites d’entreposage des déchets ultimes. Dans ce contexte, cette thèse est consacrée à l’étude de ces composés sur une large gamme de compositions (7,5 %mol ≤ Am/(U+Am) ≤ 70 %mol) focalisée sur leur fabrication à partir d’oxydes simples et l’évaluation de leur stabilités structurales, thermodynamique et sous auto-irradiation. Les résultats mettent en évidence l’influence majeure de la réduction de l’américium en Am+III, aussi bien dans les mécanismes de formation de la solution solide U1-xAmxO2±δ par voie solide que dans la stabilisation de cations d’uranium oxydés, accompagnés de la formation de défauts dans le sous-réseau d’oxygène tels que des lacunes et des clusters cuboctaédriques. Par ailleurs, les données acquises concernant la stabilité en température des composés U1-xAmxO2±δ (existence d’une lacune de miscibilité, comportement en vaporisation) ont été comparées à des calculs basés sur un nouveau modèle thermodynamique décrivant le système ternaire U-Am-O. Enfin, les effets structuraux de l’auto-irradiation α dans les composés U1-xAmxO2±δ ont été analysés par DRX, XAS et MET, permettant d’étudier l’influence de la teneur en américium sur le gonflement structural et de décrire l’évolution des défauts structuraux radio-induits. / Americium isotopes represent a significant part of high-level and long-lived nuclear waste in spent fuels. Among the envisaged reprocessing scenarios, their transmutation in fast neutron reactors using uranium-americium mixed-oxide pellets (U1-xAmxO2±δ) is a promising option which would help decrease the ecological footprint of ultimate waste repository sites. In this context, this thesis is dedicated to the study of such compounds over a wide range of americium contents (7.5 at.% ≤ Am/(U+Am) ≤ 70 at.%), with an emphasis on their fabrication from single-oxide precursors and the assessment of their structural and thermodynamic stabilities, also taking self-irradiation effects into account. Results highlight the main influence of americium reduction to Am+III, not only on the mechanisms of solid-state formation of the U1-xAmxO2±δ solid solution, but also on the stabilization of oxidized uranium cations and the formation of defects in the oxygen sublattice such as vacancies and cuboctahedral clusters. In addition, the data acquired concerning the stability of U1-xAmxO2±δ compounds (existence of a miscibility gap, vaporization behavior) were compared to calculations based on new thermodynamic modelling of the U-Am-O ternary system. Finally, α-self-irradiation-induced structural effects on U1-xAmxO2±δ compounds were analyzed using XRD, XAS and TEM, allowing the influence of americium content on the structural swelling to be studied as well as the description of the evolution of radiation-induced structural defects.

Déterminer les protéines cibles de l’uranium est un enjeu majeur dans la détermination de la toxicité de ce métal et la conception d’agents décorporants. Dans ce contexte, ce travail étudie les possibilités offertes par le couplage CE-ICP/MS dans la détection de complexes protéine-uranium. Par des conditions de séparation judicieusement choisies, il est possible d’obtenir une distribution de l’uranium dans des échantillons de complexité moyenne. Cette approche a été validée sur des protéines cibles connues (seules ou en mélange) pour lesquelles les constantes d’équilibre apparentes ont été déterminées avec une justesse comparable à celle des méthodes biophysiques. L’intérêt de ce couplage a été illustré au travers de diverses applications. Ainsi l’analyse directe de sérum a confirmé l’implication forte de la fétuine, une glycoprotéine humaine, dans le devenir de l’uranium dans le sang. De plus, l’intégration ce couplage dans une approche multi-techniques (ICP/MS, DLS, CE-ICP/MS) a permis d’étudier l’influence de l’uranium dans la formation de particules de calciprotéines et fournit la preuve du maintien de l’interaction protéine-uranium dans de tels édifices. / Identification of proteins targeted by uranium is of major concern in the determination of uranium toxicity and the development of decorporation agents. In this study, we examine the capabilities offered by hyphenated CE - ICP/MS for the detection of protein-uranium complexes. With judicious separation conditions, it is possible to obtain the uranium distribution in samples of moderate complexity. This approach was validated by using known proteins targeted by uranium (individually or in simple mixtures). Apparent equilibrium constants were determined with an accuracy similar to the ones obtained by biophysical methods. The interest of using this hyphenation was illustrated through diverse applications. The direct analysis of human serum confirmed the strong involvement of fetuin, a human glycoprotein, in the uranium blood distribution. Last but not least, the integration of this hyphenation into a multi-techniques approach (ICP/MS, DLS, CE-ICP/MS) allowed evaluating the influence of uranium on the formation of calciprotein particles and provided a proof of the preservation of protein-uranium complexes in such conditions.