A922 Sequential measurement of 1 hour creatinine clearance (1-CRCL) in critically ill patients at risk of acute kidney injury (AKI)

Meeting abstrac

Etude de systèmes et scénarios électronucléaires double strate de transmutation des actinides mineurs en ADS

The French law of 28th June 2006 regarding advanced nuclear waste management requires a scientific assessment to define future industrial strategies. The present PhD thesis was carried in this framework and concerns specifically the research axis of minoractinides transmutation. A high power Accelerator Driven System (ADS) concept is developed at SUBATECH for this purpose. A 1 GeV proton beam feeds three liquid lead-bismuth spallation targets. The MUltiple Spallation Target (MUST) ADS reaches the thermal powers up to 1 GW with a high specific power. A nuclear reactor dimensioning method has been developed and applied to different double strata scenarios. In these scenarios, SFR (Sodium FastReactors) or PWR (Pressurized Water Reactors) power reactors produce minor actinides that will be transmuted into ADS. In each core (SFR and ADS), the plutonium multi-reprocessing strategy is performed while ADS subcritical core also multi-reprocesses minor actinides. To limit the core reactivity and improve the fuel thermal conductivity, the minor actinides fuel is mixed with MgO inert matrix. Nuclear branches with lead and sodium coolants for the ADS, have been studied for different irradiation times and two transmutation strategies have been assessed : whether whole minor actinides, whether americium only is tranmuted. The thesis presents precisely the MUST ADS design methodology and the calculations to get a fuel composition at equilibrium. Then a one cycle evolution is performed and analysed for the fuel and the multiplication factor. Radiotoxicity and thermal power of the waste produced are then compared. Finally, the study of double strata scenarios is performed to analyse the plutonium and minor actinides inventories in cycle and also the waste produced according to the transmutation strategies applied and the first stratum evolution.La loi française du 28 juin 2006, sur la gestion des déchets radioactifs, demande une évaluation pour définir la future stratégie industrielle. L’étude présentée ici, concerne plus spécifiquement l’axe de recherche sur la transmutation des actinides mineurs. Dans ce but, un concept d’ADS (Accelerator DrivenSystem) de haute puissance a été développé à SUBATECH. Dans ce réacteur sous-critique, un faisceau de protons de 1 GeV alimente trois cibles de spallation de plomb-bismuth. L’ADS MUST (MUltipleSpallation Target) peut ainsi atteindre une puissance thermique de plus de 1 GW avec une densité de puissance élevée. Une méthode de dimensionnement de ces réacteurs a été développée et appliquée pour différents scénarios double strate. Dans ces scénarios, des réacteurs électrogènes de type SFR (Sodium Fast Reactors) ou REP (Réacteurs à Eau Pressurisée) produisent des actinides mineurs destinés à être transmutés en ADS. Dans chaque cœur, un multi-recyclage du plutonium est réalisé et dans les réacteurs sous-critiques les éléments à transmuter le sont également. Pour limiter la réactivité du cœur et améliorer la conductivité thermique, le combustible contenant les actinides mineurs est mélangé à une matrice inerte de MgO. Des filières, avec des ADS à caloporteurs plomb et sodium, ont été étudiées pour différentes durées d’irradiation, et deux stratégies de transmutation : soit l’ensemble des actinides mineurs, soit seulement l’américium est incinéré. Le dimensionnement des ADS MUST de chaque filière et de leur combustible à l’équilibre est présenté dans cette thèse. Puis l’évolution du combustible et du coefficient de multiplication, sur un cycle, est réalisée et analysée. La radiotoxicité et la puissance thermique des déchets produits sont ensuite comparées. Enfin, l’étude de scénarios double strate est effectué afin d’analyser les inventaires d’actinides mineurs et de plutonium en cycle, ainsi que les déchets produits en fonction de la stratégie de transmutation adoptées et de l’évolution de la première strate

Study of nuclear energy systems and double strata scenarios for minor actinides transmutation in ADS

La loi française du 28 juin 2006, sur la gestion des déchets radioactifs, demande une évaluation pour définir la future stratégie industrielle. L’étude présentée ici, concerne plus spécifiquement l’axe de recherche sur la transmutation des actinides mineurs. Dans ce but, un concept d’ADS (Accelerator DrivenSystem) de haute puissance a été développé à SUBATECH. Dans ce réacteur sous-critique, un faisceau de protons de 1 GeV alimente trois cibles de spallation de plomb-bismuth. L’ADS MUST (MUltipleSpallation Target) peut ainsi atteindre une puissance thermique de plus de 1 GW avec une densité de puissance élevée. Une méthode de dimensionnement de ces réacteurs a été développée et appliquée pour différents scénarios double strate. Dans ces scénarios, des réacteurs électrogènes de type SFR (Sodium Fast Reactors) ou REP (Réacteurs à Eau Pressurisée) produisent des actinides mineurs destinés à être transmutés en ADS. Dans chaque cœur, un multi-recyclage du plutonium est réalisé et dans les réacteurs sous-critiques les éléments à transmuter le sont également. Pour limiter la réactivité du cœur et améliorer la conductivité thermique, le combustible contenant les actinides mineurs est mélangé à une matrice inerte de MgO. Des filières, avec des ADS à caloporteurs plomb et sodium, ont été étudiées pour différentes durées d’irradiation, et deux stratégies de transmutation : soit l’ensemble des actinides mineurs, soit seulement l’américium est incinéré. Le dimensionnement des ADS MUST de chaque filière et de leur combustible à l’équilibre est présenté dans cette thèse. Puis l’évolution du combustible et du coefficient de multiplication, sur un cycle, est réalisée et analysée. La radiotoxicité et la puissance thermique des déchets produits sont ensuite comparées. Enfin, l’étude de scénarios double strate est effectué afin d’analyser les inventaires d’actinides mineurs et de plutonium en cycle, ainsi que les déchets produits en fonction de la stratégie de transmutation adoptées et de l’évolution de la première strate.The French law of 28th June 2006 regarding advanced nuclear waste management requires a scientific assessment to define future industrial strategies. The present PhD thesis was carried in this framework and concerns specifically the research axis of minoractinides transmutation. A high power Accelerator Driven System (ADS) concept is developed at SUBATECH for this purpose. A 1 GeV proton beam feeds three liquid lead-bismuth spallation targets. The MUltiple Spallation Target (MUST) ADS reaches the thermal powers up to 1 GW with a high specific power. A nuclear reactor dimensioning method has been developed and applied to different double strata scenarios. In these scenarios, SFR (Sodium FastReactors) or PWR (Pressurized Water Reactors) power reactors produce minor actinides that will be transmuted into ADS. In each core (SFR and ADS), the plutonium multi-reprocessing strategy is performed while ADS subcritical core also multi-reprocesses minor actinides. To limit the core reactivity and improve the fuel thermal conductivity, the minor actinides fuel is mixed with MgO inert matrix. Nuclear branches with lead and sodium coolants for the ADS, have been studied for different irradiation times and two transmutation strategies have been assessed : whether whole minor actinides, whether americium only is tranmuted. The thesis presents precisely the MUST ADS design methodology and the calculations to get a fuel composition at equilibrium. Then a one cycle evolution is performed and analysed for the fuel and the multiplication factor. Radiotoxicity and thermal power of the waste produced are then compared. Finally, the study of double strata scenarios is performed to analyse the plutonium and minor actinides inventories in cycle and also the waste produced according to the transmutation strategies applied and the first stratum evolution

Etude de systèmes et scénarios électronucléaires double strate de transmutation des actinides mineurs en ADS

La loi française du 28 juin 2006, sur la gestion des déchets radioactifs, demande une évaluation pour définir la future stratégie industrielle. L étude présentée ici, concerne plus spécifiquement l axe de recherche sur la transmutation des actinides mineurs. Dans ce but, un concept d ADS (Accelerator DrivenSystem) de haute puissance a été développé à SUBATECH. Dans ce réacteur sous-critique, un faisceau de protons de 1 GeV alimente trois cibles de spallation de plomb-bismuth. L ADS MUST (MUltipleSpallation Target) peut ainsi atteindre une puissance thermique de plus de 1 GW avec une densité de puissance élevée. Une méthode de dimensionnement de ces réacteurs a été développée et appliquée pour différents scénarios double strate. Dans ces scénarios, des réacteurs électrogènes de type SFR (Sodium Fast Reactors) ou REP (Réacteurs à Eau Pressurisée) produisent des actinides mineurs destinés à être transmutés en ADS. Dans chaque cœur, un multi-recyclage du plutonium est réalisé et dans les réacteurs sous-critiques les éléments à transmuter le sont également. Pour limiter la réactivité du cœur et améliorer la conductivité thermique, le combustible contenant les actinides mineurs est mélangé à une matrice inerte de MgO. Des filières, avec des ADS à caloporteurs plomb et sodium, ont été étudiées pour différentes durées d irradiation, et deux stratégies de transmutation : soit l ensemble des actinides mineurs, soit seulement l américium est incinéré. Le dimensionnement des ADS MUST de chaque filière et de leur combustible à l équilibre est présenté dans cette thèse. Puis l évolution du combustible et du coefficient de multiplication, sur un cycle, est réalisée et analysée. La radiotoxicité et la puissance thermique des déchets produits sont ensuite comparées. Enfin, l étude de scénarios double strate est effectué afin d analyser les inventaires d actinides mineurs et de plutonium en cycle, ainsi que les déchets produits en fonction de la stratégie de transmutation adoptées et de l évolution de la première strate.The French law of 28th June 2006 regarding advanced nuclear waste management requires a scientific assessment to define future industrial strategies. The present PhD thesis was carried in this framework and concerns specifically the research axis of minoractinides transmutation. A high power Accelerator Driven System (ADS) concept is developed at SUBATECH for this purpose. A 1 GeV proton beam feeds three liquid lead-bismuth spallation targets. The MUltiple Spallation Target (MUST) ADS reaches the thermal powers up to 1 GW with a high specific power. A nuclear reactor dimensioning method has been developed and applied to different double strata scenarios. In these scenarios, SFR (Sodium FastReactors) or PWR (Pressurized Water Reactors) power reactors produce minor actinides that will be transmuted into ADS. In each core (SFR and ADS), the plutonium multi-reprocessing strategy is performed while ADS subcritical core also multi-reprocesses minor actinides. To limit the core reactivity and improve the fuel thermal conductivity, the minor actinides fuel is mixed with MgO inert matrix. Nuclear branches with lead and sodium coolants for the ADS, have been studied for different irradiation times and two transmutation strategies have been assessed : whether whole minor actinides, whether americium only is tranmuted. The thesis presents precisely the MUST ADS design methodology and the calculations to get a fuel composition at equilibrium. Then a one cycle evolution is performed and analysed for the fuel and the multiplication factor. Radiotoxicity and thermal power of the waste produced are then compared. Finally, the study of double strata scenarios is performed to analyse the plutonium and minor actinides inventories in cycle and also the waste produced according to the transmutation strategies applied and the first stratum evolution.NANTES-ENS Mines (441092314) / SudocSudocFranceF

A new PoweR histOry generaTor tOol (PROTO) for French nuclear power stations at IRSN

International audienceFrom nuclear fuel cycle scenario studies to interdisciplinary ones, like economics, the nuclear energy request along the fuel life is a determining factor that has to be taken into account. In this context, the Department of neutronics and criticality safety assessment (IRSN) has developed a Monte Carlo tool (PROTO) to provide realistic power histories in order to simulate the power history request for the typical reactors composing the French nuclear eet. The rst application of this tool is related to study the variations of the isotopic inventory inside the core of a nuclear reactor. These variations are an important input for the study of crisis scenarios, for instance, to estimate the release of radioactive elements in the atmosphere.The Monte Carlo tool is composed of two stages. The rst one analyses a database of the energy provided by French nuclear power stations in the last seven years. Power frequency distribution, amplitude power uctuations, shutdowns width distribution, shutdown periodicity, and power patterns are some pieces of information extracted from the database to de ne probability distributions used in the second stage of PROTO. In the second stage, PROTO uses the Monte Carlo method to sample on the extracted probability distributions to generate realistic power histories. The routine implemented is notabily able to reproduce the typical fuel management cycles, taking into account shutdown and maintenance periods extracted from realistic data. The power histories in between two shutdowns is able to reproduce typical reactor power demand, including frequencies and uctuation probabilities.Realistic power histories are delivered for di erent nominal powers and di erent bins (hours, days, and MW*d/kg). The success of the PROTO test pushed the enhancement of the tool. A new stage of the code has been designed to adapt and provide the results on the input format of well-know nuclear core simulation codes like CASMO and MCNP

A new PoweR histOry generaTor tOol (PROTO) for French nuclear power stations at IRSN

International audienceFrom nuclear fuel cycle scenario studies to interdisciplinary ones, like economics, the nuclear energy request along the fuel life is a determining factor that has to be taken into account. In this context, the Department of neutronics and criticality safety assessment (IRSN) has developed a Monte Carlo tool (PROTO) to provide realistic power histories in order to simulate the power history request for the typical reactors composing the French nuclear eet. The rst application of this tool is related to study the variations of the isotopic inventory inside the core of a nuclear reactor. These variations are an important input for the study of crisis scenarios, for instance, to estimate the release of radioactive elements in the atmosphere.The Monte Carlo tool is composed of two stages. The rst one analyses a database of the energy provided by French nuclear power stations in the last seven years. Power frequency distribution, amplitude power uctuations, shutdowns width distribution, shutdown periodicity, and power patterns are some pieces of information extracted from the database to de ne probability distributions used in the second stage of PROTO. In the second stage, PROTO uses the Monte Carlo method to sample on the extracted probability distributions to generate realistic power histories. The routine implemented is notabily able to reproduce the typical fuel management cycles, taking into account shutdown and maintenance periods extracted from realistic data. The power histories in between two shutdowns is able to reproduce typical reactor power demand, including frequencies and uctuation probabilities.Realistic power histories are delivered for di erent nominal powers and di erent bins (hours, days, and MW*d/kg). The success of the PROTO test pushed the enhancement of the tool. A new stage of the code has been designed to adapt and provide the results on the input format of well-know nuclear core simulation codes like CASMO and MCNP

Criticality configuration design methodology applied to the design of fuel debris experiment in the new STACY

International audienceThe new critical assembly STACY will be able to contribute to the validation of criticality calculations related to the fuel debris. The experimental core designs are in progress in the frame of JAEA/IRSN collaboration. This paper presents the method applied to optimize the design of the new STACY core to measure the criticality characteristics of pseudo fuel debris that simulated Molten Core Concrete Interaction (MCCI) of the fuel debris. To ensure that a core configuration is relevant for code validation, it is important to evaluate the reactivity worth of the main isotopes of interest and their keff sensitivity to their cross sections. In the case of the fuel debris described in this study, especially for the concrete composition, silicon is the nucleus with the highest keff sensitivity to the cross section. For this purpose, some parameters of the core configuration, were adjusted using optimization algorithm to find effciently the optimal core configurations to obtain high sensitivity of silicon capture cross section. Based on these results, realistic series of experiments for fuel debris in the new STACY could be defined to obtain an interesting feedback for the MCCI. This methodology is useful to design other experimental conditions of the new STACY

Social norms from a goal-system point of view: Contributions of activity analysis

International audienceIn this article, we used a social injunctive norm to incentivize the elaboration of energy-efficientprojects within a building renovation simulation application. We manipulated the norm saliency(presence on the interface) and compared its effect to that of an arbitrary set goal and a no-goalcondition (control). Results show that both an injunctive norm and an explicit goal, when salient,led to more energy-efficient designs. Furthermore, participants exposed to the salient injunctivenorm identified important parameters more quickly, were more efficient, and were moreconsistently focused on energy (vs. furnishing). Implications for theory and methodology forfurther experiments are discussed

Using Regulatory Focus Theory for a Mobile Device Renovation Application: Nudging Users Towards Building Green Houses

International audienceWe propose a preliminary study aiming to apply RegulatoryFocus Theory to building renovations. We developed a mobile applicationto test if a priming technique could influence users and the choicesthey make when it comes to select equipment such as a heater or thermalinsulation. First results show that choices might be affected by thepriming task. The question remains though as to how to ecologically andnon-intrusively prime users of such applications

Development of a multi-zone fuel loading model for scenario studies involving ASTRID-like SFRs with the CLASS code

Many scenario studies conducted by several countries consider the progressive deployment of low void effect Sodium-cooled Fast Reactor (SFR) [1]. Different options are investigated regarding the deployment time of this kind of Generation IV reactor, depending on the global nuclear energy development and the national energy mix strategies. In France, the SFR core design often used in this type of scenario is based on the 600 MWe ASTRID concept developed by the CEA and its industrial partners [2]. To reach a negative void coefficient, the core is divided in two radial parts: an inner and an outer core, which alternate different fertile and fissile zones.One challenge to simulate fuel cycle with fuel reprocessing is to consider the evolution of the materi-als to be recycled over time. Indeed, spent fuel compositions vary at each reprocessing as it de-pends of each fuel history (in which reactor it has been irradiated, burn-up achieved, cooling time…). Hence, to build a fresh fuel adapted to one reactor specificities, the CLASS (Core Library for Ad-vanced Scenario Simulation) software [3], a dynamic fuel cycle simulation code developed by CNRS in collaboration with IRSN, uses dedicated fuel loading models. In the case of this SFR, the aim is to keep the fuel heterogeneity of the core. To do that, the devel-opment of a new dedicated fresh fuel loading model taking into account the different fuel zones of the reactor was needed. This model is based on the reactor's neutron characteristics and it is usable for a wide variability of spent fuels to be recycled. In this way, for a given isotopic composition, the Pu contents of both the inner and the outer core are iteratively adjusted to reach a target power distri-bution in the core and a target multiplication factor (keff) at the beginning of cycle. An analysis of this SFR behavior during irradiation shows a relation between the power distribution and the ratio of Pu contents, between the inner and outer core. This relation is used by the model to calculate the initial Pu contents for a given isotopic composition assuring the target power distribu-tion. Then, to determine the keff associated to that specific fresh fuel composition, the model uses Artificial Neural Network (ANN) trained on a corresponding databank. This databank is composed of 1000 full core depletion Monte Carlo simulations generated with the VESTA code [4], in which MCNP is used as the transport solver. Each calculation differs from the other by the initial fresh fuel sam-pled in the parameter space of compositions covering many potential SFR fuel management strate-gies. This new model completes the implementation of a previous multi-zone fuel irradiation model devel-oped for this SFR [5]. Thanks to these two multi-zone models, the simulation of scenarios integrating multi-zone SFR with the code CLASS shows that the plutonium breeder, break-even or burner SFR property is highly dependent on its fresh fuel composition