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Auswahl der wissenschaftlichen Literatur zum Thema „Sodium ion accumulators“
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Zeitschriftenartikel zum Thema "Sodium ion accumulators"
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Máca, Josef, Marie Sedlarikova, Jiri Libich, Tomáš Kazda und Kamil Jaššo. „Ceramic Based Negative Electrode for Sodium Ion Accumulators“. ECS Transactions 95, Nr. 1 (18.11.2019): 211–15. http://dx.doi.org/10.1149/09501.0211ecst.
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Eshel, A. „Effects of NaCl and KCl on Growth and Ionic Composition of the Halophytic C4 Succulent Chenopods Salsola kali, Suaeda monoica and Suaeda aegyptiaca“. Functional Plant Biology 12, Nr. 3 (1985): 319. http://dx.doi.org/10.1071/pp9850319.
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Salsola kali, Suaeda monoica and Suaeda aegyptiaca plants were grown in sand culture under controlled conditions and treated with half-strength Hoagland's nutrient solution (control), and control plus 150 mol m-3 KCl or NaCl. Fresh weight of Salsola kali was doubled in the NaCl and KCl treatments, but the increase in dry matter as compared with the control was not significant. Ionic content in this species revealed high selectivity for K v. Na. Fresh weight of Suaeda monoica and S. aegyptiaca was raised by NaCl 5 and 10 times respectively. Control and KCl-treated plants were poorly developed and plants of S. aegyptiaca exhibited sodium deficiency symptoms under these treatments. The two Suaeda species had lower selectivity of K v. Na than Salsola kali. Of the two annual species, Suaeda kali and S. aegyptiaca, S. kali flowered under all three treatments, whereas S. aegyptiaca flowered only under the Na treatment. In spite of the fact that all three species are inorganic ion accumulators and C4-succulent chenopods, they exhibit wide differences in their response to the two chloride salts.
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Meutzner, Falk, Tina Nestler, Juliane Hanzig, Matthias Zschornak, Mateo Ureña de Vivanco, Wolfram Münchgesang, Robert Schmid, Charaf Cherkouk, Tilmann Leisegang und Dirk Meyer. „Categorization of electrochemical storage materials en route to new concepts“. Acta Crystallographica Section A Foundations and Advances 70, a1 (05.08.2014): C364. http://dx.doi.org/10.1107/s2053273314096351.
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Because of their broad range of applications, electrochemical energy storage devices are the subject of a growing field of science and technology. Their unique features of high practical energy and power densities and low prices allow mobile and stationary applications. A large variety of electrochemical systems has been tailored for specific applications: Lithium-ion batteries for example have been optimized for mobile applications ranging from mobile phones to electric vehicles. On the other hand, sodium-sulphur accumulators – among others – have been developed for stationary applications to account for the capricious nature of renewable energies. Chemistry, physics and materials science have led to the optimization of existing cell-chemistries and the development of new concepts such as all-liquid or all-solid state batteries as well as high-energy density metal-air batteries. The aim of the BMBF (Federal Ministry of Education and Research, Germany)-financed project "CryPhysConcept" is to develop new concepts for electrochemical energy storage applying a crystallographic approach. First, a categorization of the main solid components of batteries based on their underlying working principles is suggested. Second, an algorithm for the identification of suitable new materials and material combinations, based on economical, ecological and material properties as well as crystallographic parameters, is presented. Based on these results, new concepts using multi-valent metal ions are proposed. Theoretical as well as experimental results including an iron-ion approach are presented.
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Brachet, Anna, Christophe Leterrier, Marie Irondelle, Marie-Pierre Fache, Victor Racine, Jean-Baptiste Sibarita, Daniel Choquet und Bénédicte Dargent. „Ankyrin G restricts ion channel diffusion at the axonal initial segment before the establishment of the diffusion barrier“. Journal of Cell Biology 191, Nr. 2 (18.10.2010): 383–95. http://dx.doi.org/10.1083/jcb.201003042.
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In mammalian neurons, the precise accumulation of sodium channels at the axonal initial segment (AIS) ensures action potential initiation. This accumulation precedes the immobilization of membrane proteins and lipids by a diffusion barrier at the AIS. Using single-particle tracking, we measured the mobility of a chimeric ion channel bearing the ankyrin-binding motif of the Nav1.2 sodium channel. We found that ankyrin G (ankG) limits membrane diffusion of ion channels when coexpressed in neuroblastoma cells. Site-directed mutants with decreased affinity for ankG exhibit increased diffusion speeds. In immature hippocampal neurons, we demonstrated that ion channel immobilization by ankG is regulated by protein kinase CK2 and occurs as soon as ankG accumulates at the AIS of elongating axons. Once the diffusion barrier is formed, ankG is still required to stabilize ion channels. In conclusion, our findings indicate that specific binding to ankG constitutes the initial step for Nav channel immobilization at the AIS membrane and precedes the establishment of the diffusion barrier.
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Guerrero-Alves, José, Ildefonso Pla-Sentís und Rafael Camacho. „A model to explain high values of pH in an alkali sodic soil“. Scientia Agricola 59, Nr. 4 (Dezember 2002): 763–70. http://dx.doi.org/10.1590/s0103-90162002000400021.
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For alkali sodic soils (pH>8.5), the "hydrolysis of exchangeable sodium" has been used as a possible explanation for the alkalinity production and rise in pH of these soils. As an alternative to this hypothesis, a model was developed to simulate and to explain that the alkalinity production and rise in pH is possible in a soil that accumulates alkaline sodium salts and CaCO3. Several simulations were performed by using different combinations of CO2 partial pressures (P), presence or absence of MgCO3, along with experimental values of exchangeable sodium percentage (ESP) and ion concentrations in saturation extracts from an alkali sodic soil (named Pantanal). A hypothetical system with similar conditions to the Pantanal soil but with a Gapon selectivity coefficient (KG) of 0.01475 (mmol L-1)-1/2 was also considered. Good agreement was obtained between experimental and predicted values for pH and ion concentrations in the soil solution when the model (without MgCO3) was applied to the Pantanal soil. However, KG values calculated for the Pantanal soil were generally higher than 0.01475 (mmol L-1)-1/2. Moreover, high pH values and elevated ionic strength were obtained when a KG of 0.01475 (mmol L-1)-1/2 was used at high ESP (similar to those found in the Pantanal soil). KG values obtained for the Pantanal soil and the results obtained in the simulation of the hypothetical system are suggesting that a value higher than 0.01475 (mmol L-1)-1/2 should be used to adequately simulate the behavior of the Pantanal soil at low ionic strength and high ESP values.
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Ferguson, Louise, und Steven R. Grattan. „How Salinity Damages Citrus: Osmotic Effects and Specific Ion Toxicities“. HortTechnology 15, Nr. 1 (Januar 2005): 95–99. http://dx.doi.org/10.21273/horttech.15.1.0095.
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There are two ways salinity can damage citrus: direct injury due to specific ions, and osmotic effects. Specific ion toxicities are due to accumulation of sodium, chloride, and/or boron in the tissue to damaging levels. The damage is visible as foliar chlorosis and necrosis and, if severe enough, will affect orchard productivity. These ion accumulations occur in two ways. The first, more controllable and less frequent method, is direct foliar uptake. Avoiding irrigation methods that wet the foliage can easily eliminate this form of specific ion damage. The second way specific ion toxicity can occur is via root uptake. Certain varieties or rootstocks are better able to exclude the uptake and translocation of these potentially damaging ions to the shoot and are more tolerant of salinity. The effect of specific ions, singly and in combination, on plant nutrient status can also be considered a specific ion effect. The second way salinity damages citrus is osmotic effects. Osmotic effects are caused not by specific ions but by the total concentration of salt in the soil solution produced by the combination of soil salinity, irrigation water quality, and fertilization. Most plants have a threshold concentration value above which yields decline. The arid climates that produce high quality fresh citrus fruit are also the climates that exacerbate the salt concentration in soil solution that produces the osmotic effects. Osmotic effects can be slow, subtle, and often indistinguishable from water stress. With the exception of periodic leaching, it is difficult to control osmotic effects and the cumulative effects on woody plants are not easily mitigated. This review summarizes recent research for both forms of salinity damage: specific ion toxicity and osmotic effects.
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Betz, A. Lorris, Richard F. Keep, Mary E. Beer und Xiao-Dan Ren. „Blood—Brain Barrier Permeability and Brain Concentration of Sodium, Potassium, and Chloride during Focal Ischemia“. Journal of Cerebral Blood Flow & Metabolism 14, Nr. 1 (Januar 1994): 29–37. http://dx.doi.org/10.1038/jcbfm.1994.5.
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Brain edema formation during the early stages of focal cerebral ischemia is associated with an increase in both sodium content and blood–brain barrier (BBB) sodium transport. The goals of this study were to determine whether chloride is the principal anion that accumulates in ischemic brain, how the rate of BBB transport of chloride compares with its rate of accumulation, and whether the stimulation seen in BBB sodium transport is also seen with other cations. Focal ischemia was produced by occlusion of the middle cerebral artery (MCAO) in anesthetized rats. Over the first 6 h after MCAO, the amount of brain water in the center of the ischemic cortex increased progressively at a rate of 0.15 ± 0.02 (SE) g/g dry wt/h. This was accompanied by a net increase in brain sodium (48 ± 12 μmol/g dry wt/h) and a loss of potassium (34 ± 7 μmol/g dry wt/h). The net rate of chloride accumulation (16 ± 1 μmol/g dry wt/h) approximated the net rate of increase of cations. Three hours after MCAO, the BBB permeability to three ions (22Na, 36Cl, and 86Rb) and two passive permeability tracers {[3H]α-aminoisobutyric acid (3H]AIB) and [14C]urea} was determined. Permeability to either passive tracer was not increased, indicating that the BBB was intact. The rate of 36Cl influx was 3 times greater and the rate of 22Na influx 1.8 times greater than their respective net rates of accumulation in ischemic brain. The BBB permeability to 22Na relative to that of [3H]AIB was significantly increased in the ischemic cortex, the relative permeability to 86Rb was significantly decreased, and the relative permeability to 36Cl was unchanged. These results indicate that the stimulation in BBB sodium transport is specific for sodium. Further, chloride accumulates with sodium in brain during the early stages of ischemia; however, its rate of accumulation is low compared with its rate of transport from blood to brain. Therefore, inhibition of BBB sodium transport is more likely to reduce edema formation than is inhibition of BBB chloride transport. This study demonstrates that chloride is the principal anion that accompanies the accumulation of sodium in ischemic brain, but its rate of accumulation in brain is much less than its rate of movement into brain, and therefore inhibition of chloride uptake would have little effect on brain edema formation. There is a specific acceleration of blood-to-brain sodium transport during ischemia that is not seen with another positively charged ion, 86Rb. This is consistent with stimulation of brain capillary Na,K-ATPase activity in response to the elevated extracellular potassium concentration. Inhibition of potassium influx across the BBB would probably be more successful in lessening edema formation than accelerating potassium efflux. However, inhibition of blood-to-brain sodium transport is likely to be a more effective approach to reducing brain edema formation during the early stages of cerebral ischemia.
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DEL PIERO, STEFANIA, LUCIANO MASIERO und SANDRA CASELLATO. „Toxicity and bioaccumulation of fluoride ion on Branchiura sowerbyi, Beddard, (Oligochaeta, Tubificidae)“. Zoosymposia 9, Nr. 1 (12.06.2014): 44–50. http://dx.doi.org/10.11646/zoosymposia.9.1.9.
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Fluoride concentrations are increasing significantly in many aquatic ecosystems as a consequence of human activities (agrochemicals, pharmaceuticals, refrigerants, pesticides, surfactant compounds). Several investigations have revealed that sensitivity to fluorides and safe concentrations vary greatly within classes, families and genera. Aquatic oligochaetes have often been used for pollution assessment and accumulation testing, but no information has been given about tolerance to fluoride ion. Among endobenthic tubificids Branchiura sowerbyi is easily identifiable (evident posterior gills, large size) and particularly useful for tissue requirements in chemical analysis. The purpose of this study was to examine the tolerance of this tubificid to fluoride ion and its bioaccumulation capacity by performing short (LC50 96h) and long-term (18 day) experiments at different temperatures (17°C and 22 °C). LC50 values (91.3 and 61.7 mg/L for 17°C and 22°C respectively), especially in the presence of sediment (267.6 and 80.1 mg/L for 17°C and 22°C respectively) showed that B. sowerbyi is more resistant to fluoride than other freshwater invertebrates. Fluoride became more toxic with increased temperature, demonstrating that seasonal temperature changes could influence the sensitivity of this freshwater tubificid. Bioaccumulation was lower when the organisms were exposed to sodium fluoride in the absence of sediment, indicating that this animal also accumulates fluoride by ingesting sediment.
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Meloni, Diego A., und Carlos A. Martínez. „Glycinebetaine improves salt tolerance in vinal (Prosopis ruscifolia Griesbach) seedlings“. Brazilian Journal of Plant Physiology 21, Nr. 3 (2009): 233–41. http://dx.doi.org/10.1590/s1677-04202009000300007.
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Glycinebetaine (GB) is a very important organic osmolyte that accumulates in a number of diverse groups of plants in response to environmental stress. In some plants, increased resistance to drought, salinity and low temperature has been achieved through exogenous application of GB. In this study, the effect of exogenously applied GB (8 mM) on the ability of vinal (Prosopis ruscifolia G.) plants to withstand NaCl stress was investigated. The dry biomass of vinal showed a decrease under salt stress, but in GB-treated plants exposed to the same stress, this reduction was mitigated. Sodium accumulated in the leaves of plants grown under saline conditions, but the addition of GB to salt-grown plants reduced Na+ content by 40%. Salinity significantly reduced the K+ concentration in leaves to 65% that of non-salinized controls. In the presence of GB, leaf K+ was comparatively higher, reaching as much as 90% of the control concentration. The sodium: potassium ratio in leaves was significantly higher in salt-stressed plants, but this ratio was lowered significantly by the addition of GB. When compared to control plants, NaCl stress increased malondialdehyde (MDA) concentrations by 95%, but GB application reduced the MDA concentration in these same NaCl-treated plants. In comparison to control plants, the activity of superoxide dismutase (SOD) increased by 52% in salt-stressed plants. The addition of GB to salt-treated plants stimulated SOD activity twice that of the non-salizined control. These results suggest that, in addition to protecting membranes, GB-enhanced salinity tolerance in vinal may involve an antioxidant mechanism involving enhanced SOD activity and improving the ion homeostasis under conditions of high salinity.
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Gao, Jun, Hui Xiao Wang, Hai Jun Liu, Jian Yin und Xuan Zhao. „Effects of Reclaimed Water Irrigation upon Soil Quality“. Advanced Materials Research 610-613 (Dezember 2012): 3022–26. http://dx.doi.org/10.4028/www.scientific.net/amr.610-613.3022.
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To analyze reclaimed water irrigation effects upon soil quality, including indicators of secondary salinization and heavy metal accumulation, a field experiment in the typical reclaimed water irrigated area (Xin-he irrigated area, Tongzhou District) was carried out in this study. The treated soils for sampling and analyzing were irrigated with reclaimed water and well water. Soil heavy metal contents were determined by ICP-AES, while those of soil salt ions were determined by DX 600. Results show that, reclaimed water irrigated soil has a significant increase in salt ion contents than well irrigated soil, with an increasing order of Na+>K+>Mg2+>Ca2+. And Ca2+、Mg2+、Na+accumulations at 40~80 cm and140~180 cm are relatively critical. Vertical trends of sodium adsorption ratio(SAR) values of soil extraction are the same in districts irrigated with reclaimed water and well water, however, SAR values of reclaimed water irrigated soil are significantly higher than well irrigated soil, with an average of 5~6 times bigger. But values are still in the suitable level for crops. Although heavy metals(Cu、As、Ni、Pb and Zn) slightly accumulate at 140~200cm, values are still consistent with soil environmental standard grade of 1or 2. And contents of heavy metals have no obvious differences between soils irrigated with reclaimed water and well water at 0~140cm.
Dissertationen zum Thema "Sodium ion accumulators"
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Šátek, Dominik. „Teplotní závislost kapacity negativní elektrody pro sodno – iontové akumulátory“. Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2021. http://www.nusl.cz/ntk/nusl-442527.
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This work focuses on sodium-ion batteries. It describes the basic principles of accumulators, focusing more on secondary cells, their electrodes, especially negative electrodes. The work is lightly based on the basics of lithium-ion batteries. The practical part of the work is the production of negative electrodes Na2Ti3O7, which are further measured at three different temperatures. These measurements are then evaluated.
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Simone, Virginie. „Développement d'accumulateurs sodium-ion“. Thesis, Université Grenoble Alpes (ComUE), 2016. http://www.theses.fr/2016GREAI092/document.
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Au vu d’une demande croissante pour un stockage d’énergie à grande échelle, il est préférable de se tourner vers des matériaux peu coûteux et répandus. De ce point de vue, le sodium, qui présente des caractéristiques très proches de celles du lithium, présente également l’avantage d’être peu coûteux, abondant et réparti uniformément dans le monde. Cette thèse porte sur l’étude d’un système complet Na-ion constitué d’un carbone dur à l’électrode négative et d’un oxyde lamellaire à l’électrode positive. Un volet sur l’électrolyte a également été abordé.Concernant l’électrode négative, l’influence de la température de pyrolyse de la cellulose sur la structure des carbones durs et sur les performances électrochimiques a été étudiée. Une graphitisation localisée, une fermeture des pores et une évolution de la porosité interne avec la température de pyrolyse ont pu être observées. Les meilleures performances électrochimiques ont été obtenues pour le matériau synthétisé à 1600 °C : une capacité réversible d’environ 300 mAh.g-1 stable sur 200 cycles est atteinte à 37,2 mA.g-1 avec une efficacité coulombique initiale de 84 %. Pour mieux comprendre les mécanismes d’insertion du sodium dans ces matériaux, des études par spectroscopie d’impédance, SAXS et EDX ont été réalisées sur des carbones durs cyclés à différents potentiels.Le matériau d’électrode positive choisi est l’oxyde lamellaire Na0,6Ni0,25Mn0,75O2. L’influence de la température de calcination a permis de faire varier le nombre de défauts d’empilement de type P3 au profit d’une phase P2 plus cristalline. Après avoir optimisé l’électrolyte à base de carbonates pour garantir la reproductibilité des tests oxyde lamellaire//sodium métal, une capacité d’oxydation de 130 mAh.g-1 a pu être atteinte au premier cycle avant de chuter fortement sur les 40 cycles suivants. Cette perte de capacité a pu être en partie expliquée par des études de DRX operando. Enfin, ces travaux ont permis d’aboutir à des systèmes complets Na-ion dont les premiers résultats sont prometteursBecause of the development of renewable energy and electric vehicles, the need for a large scale energy storage has increased. This type of storage requires a large amount of raw materials. Therefore low cost and abundant resources are necessary. Consequently the use of sodium batteries is of interest because sodium’s low cost, high abundance, and worldwide availability. This PhD thesis deals with the study of a full Na-ion cell containing a hard carbon negative electrode, and a layered oxide positive electrode. A shorter part concerns the electrolyte.Concerning the negative electrode, the first objective was to understand in detail the influence of the pyrolysis temperature of a hard carbon precursor, cellulose, on the final structure of the material and its consequences on the electrochemical performance. Many techniques were used to characterize the hard carbon structure as a function of the pyrolysis temperature. Localized graphitization, pore closure, and an increase in micropore size have been observed with increasing temperature. The best electrochemical performance has been reached with the hard carbon synthesized at 1600°C: a reversible capacity of around 300 mAh.g-1 stable over 200 cycles is obtained at 37.2 mA.g-1 with an initial coulombic efficiency of 84%. To deeper understand sodium insertion mechanisms in hard carbon structures impedance spectroscopy, SAXS and EDX were carried out on hard carbon electrodes cycled at different voltages.The layered oxide Na0.6Ni0.25Mn0.75O2 was investigated as the positive electrode. It was observed that with increasing calcination temperature the number of P3-type stacking faults decreases in favor of a more crystalline P2 phase. Then, the carbonate-based electrolyte has been optimized to guarantee the reproducibility of the electrochemical tests performed in a layered oxide//sodium metal configuration. A first oxidation capacity of around 130 mAh.g-1 is reached. However this value drops quickly after 40 cycles. Operando XRD analysis did partially explain the capacity decrease. Finally, the results of these investigations were used to design an optimized full cell which demonstrated promising performance during initial testing
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Huynh, Le Thanh Nguyen. „Les accumulateurs au sodium et sodium-ion, une nouvelle génération d’accumulateurs électrochimiques : synthèse et électrochimie de nouveaux matériaux d’électrodes performants“. Thesis, Paris Est, 2016. http://www.theses.fr/2016PESC1123/document.
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Les accumulateurs au lithium jouent un rôle important comme source d'alimentation pour les appareils électroniques portables en raison de leur forte capacité gravimétrique et volumétrique et leur haute tension. En outre, la technologie lithium-ion est la mieux placée pour une application à grande échelle, telle que le véhicule électrique, ce qui pose un problème de ressource et à terme, de coût. Une des réponses envisagées sur le plan économique et environnemental est le développement d’accumulateurs sodium-ion. Dans tous les cas, le problème scientifique consiste à proposer des matériaux d’insertion des ions sodium avec un caractère réversible de la réaction électrochimique, et une durée de vie compétitive par rapport aux systèmes au lithium. Le travail présenté se situe dans cet effort de recherche. Les potentialités de matériaux dérivés du pentoxyde de vanadium, de structure 2D, sont étudiées comme composés d’intercalation du sodium: le composé de référence V2O5, le bronze performant dérivé de V2O5 de formule K0,5V2O5, ε’-V2O5, ainsi que le composé au manganèse de type lamellaire : la birnessite sol-gel et sa forme dopée au cobalt. Les relations structure-électrochimie sont élucidées à travers une étude combinant propriétés électrochimiques, diffraction des Rayons X et spectroscopie Raman des matériaux à différents taux d’insertion, en fin de réaction et après cyclages galvanostatiques. De nouvelles phases sont obtenues et des capacités spécifiques comprises entre 100 et 160 mAh/g dans le domaine de potentiel 4V-1V peuvent être obtenues avec parfois une stabilité remarquable comme dans le cas de NaV2O5 et ε’-V2O5Since commercialization, Li-ion batteries have been playing an important role as power source for portable electronic devices because of high gravimetric, volumetric capacity and high voltage. Furthermore, the lithium-ion technology is best suited for large-scale application, such as electric vehicles, which poses a resource problem and ultimately cost. On the contrary, sodium is a most abundant element, inexpensive and similarly properties as lithium. In order to solve the problem of lithium raw resource, sodium is proposed as a solution for next generation power source storage. This work investigates the potential derivative vanadium pentoxide materials as sodium intercalation compounds: the V2O5 reference compound, the promizing potassium bronze K0,5V2O5, ε'-V2O5, as well as a lamellar manganese oxide: the sol-gel birnessite and its doped cobalt form. The structure-electrochemistry relationships are clarified through a study combining electrochemical properties, X-ray diffraction and Raman spectroscopy of materials at different insertion rate, end of the reaction and after galvanostatic cycling. New phases are highlighted and specific capacities between 100 and 160 mAh / g in the field of 4V-1V potential can be obtained with sometimes remarkably stable as in the case of NaV2O5 and ε'-V2O5
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Senguttuvan, Premkumar. „À la recherche d'électrodes négatives à base de Ti pour les accumulateurs à ions sodium“. Amiens, 2013. http://www.theses.fr/2013AMIE0122.
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Cette thèse traite du développement de nouvelles électrodes négatives à base de titane pour batteries Na-ion. Les oxydes à base de Ti4+ ont d'abord été ciblés en raison de leur cristallochimie, facilité de synthèse et stabilité vis-à-vis de l'humidité. L'un d'entre eux, le composé lamellaire Na2Ti3O7, présente une capacité réversible de 177 mAh/g à un potentiel de 0,3 V vs. Na+/Na0. Il s'agit là du potentiel le plus bas jamais rapporté pour l'intercalation d'ions Na+ dans des oxydes. Des études de diffraction des rayons X in-situ ont révélé que le processus d'intercalation (Na2Ti3O7 + 2 Na = Na4Ti3O7) est biphasique. Des calculs DFT ont non seulement permis de rendre compte des potentiels mesurés mais aussi de proposer deux modèles structuraux pour la phase réduite Na4Ti3O7, et le modèle conservant les feuillets en zig-zag de [Ti3O7]²¯ intacts a été expérimentalement confirmé par diffraction de rayons X. Cependant, quel que soit l'électrolyte que nous avons utilisé, la tenue en cyclage de Na2Ti3O7 est limitée. Ceci nous a amené à explorer des composés polyanioniques. Nous avons préparé, via un procédé basse température (170°C), un nouveau polymorphe de TiP2O7 capable d'insérer réversiblement 0,95 moles de lithium à 2. 6 V vs. Li+/Li0 et 0,88 moles de sodium à 2,3 V vs. Na+/Na0, avec une bonne tenue en cyclage. Pour maintenir cette dernière, tout en abaissant le potentiel d’insertion de Na+, nous avons eu recours à des composés de structure NASICON susceptibles de présenter le couple redox Ti3+/Ti2+ tels que Na3Ti2(PO4)3 et Ti2(SO4)3. Les mesures électrochimiques montrent que ces phases sont capables d'insérer réversiblement 1,0 and 1,7 moles of sodium à 0,45 V et 1,3 V vs. Na+/Na0 respectivement, via un mécanisme biphasé conduisant à du Ti2+ comme déduit par des mesures RPE. Cependant, comme Na2Ti3O7, ces composés présentent des tenues en cyclage très limitées. Cette chute de capacité provient de la formation d'une SEI à bas potentiel associée à la décomposition catalytique de l'électrolyte par le Ti, et empêche aujourd'hui l'utilisation de ces électrodes négatives à base de Ti dans les accumulateurs Na-ionThis thesis dwells with the development of titanium based negative electrodes for sodium-ion batteries. Titanium (IV) oxides were firstly targeted owing to their rich crystal-chemistry, easy synthesis and moisture stability. Among them layered Na2Ti3O7 was found to show a reversible capacity of 177 mAh/g at ca. 0. 3 V vs. Na+/Na0, the lowest sodium intercalation voltage ever reported for oxide materials. To understand the origin of such behavior, studies were extended to entire A2Ti3O7 (A=Li and Na) family. In situ XRD and electrochemical measurements showed that lithium and sodium intercalation into A2Ti3O7 compounds proceeds through a biphasic transformation to form A2+xTi3O7 (0≤x≤2). DFT calculations reproduced the observed voltages of lithium and sodium intercalation reactions but more importantly provided two possible structural models for the reduced A4Ti3O7 phases. The model which kept zig-zag layers of [Ti3O7]²¯ upon two mol of sodium or lithium intercalation into parent A2Ti3O7, was confirmed experimentally by XRD. Upon cycling, whatever the electrolyte composition we have tried, Na2Ti3O7 shows large capacity fading. To circumvent this issue, we explored polyanionic compounds and prepared via a low temperature process (170°C) a new polymorph of TiP2O7 capable of intercalating reversibly ca. 0. 95 mol of lithium and 0. 88 mol of sodium at 2. 6 V vs. Li+/Li0 and 2. 3 V vs. Na+/Na0 respectively, with sustained capacity upon cycling. Searching for low voltage compounds, we moved to NASICON frameworks having the Ti(III)/Ti(II) redox couple such as Na3Ti2(PO4)3 and Ti2(SO4)3. Such phases were found to reversibly intercalate 1. 0 and 1. 7 mol of sodium at 0. 45 and 1. 3 V vs. Na+/Na0 respectively, throught two-phase transformation with the Ti(II) oxidation state being confirmed from EPR measurements. Although initial capacities of 60 and 120 mAh/g were obtained for phosphate and sulfate electrodes, severe capacity fading was observed similar to that of Na2Ti3O7. This fading, whose origin is rooted in the Ti-driven catalytic decomposition of the electrolyte associated to a continuous growth of SEI, presently plague the use of these low voltage Ti-based materials in practical Na-ion cells
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Castro, Alexandre. „Développement de batteries tout solide sodium ion à base d’électrolyte en verre de chalcogénures“. Thesis, Rennes 1, 2018. http://www.theses.fr/2018REN1S126/document.
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L'évolution des consommations énergétiques au cours des dernières décennies entraîne des modifications majeures dans la conception des systèmes électriques autonomes à fournir, que ce soit pour des applications électriques ou électroniques. La nécessité présente de réaliser des générateurs capables de délivrer l'énergie suffisante, avec une garantie de sûreté maximale, impose à la recherche l'exploration de nouvelles voies de stockage. Les voies actuelles par accumulateurs au lithium tendent à montrer leurs limites, tant stratégiques qu'environnementales. Dans ce cadre, la construction de nouveaux systèmes électrochimiques mettant en œuvre le sodium ouvre une possibilité de réalisation d'accumulateurs sans lithium. Le besoin de batteries toujours plus performantes oblige à des conceptions innovantes, abandonnant la voie liquide au profit de systèmes tout solide plus sécuritaires. De plus, la miniaturisation de l'électronique conduit à revoir le dimensionnement des batteries, vers des batteries de type micro, pour lesquelles l'intérêt d'un empilement tout solide n'est plus à démontrer. Aujourd'hui, des verres de chalcogénures au soufre permettent l'accès à des conductivités ioniques qui laissent entrevoir la possibilité d'une réalisation de batteries tout solide, à la fois sous forme de micro batteries ou de batteries massives. Un effort de recherche a été porté à la formulation de ces verres de chalcogénures afin d'obtenir des conductivités ioniques maximales et des propriétés autorisant leur utilisation comme électrolyte. La modification de ces verres met alors en lumière l'intérêt des différents éléments les composant. L'étude de la mise en forme de l'électrolyte par dépôts de type couches minces (obtenues par Radio Fréquence Magnétron Sputering, RFMS) prouve la faisabilité de ces micro batteries tout solide au sodium. Par la suite, la réalisation de batteries massives tout solide a demandé la synthèse de deux matériaux de cathode (NaCrO2 et Na[Ni0,25Fe0,5Mn0,25]O2) et de deux matériaux d'anode (Na15Sn4 et Na) permettant ainsi la mise en œuvre de quatre empilements électrochimiques, tous caractérisés comme accumulateurs. Enfin, l'amélioration des interfaces grâce à un gel-polymère a permis de perfectionner les propriétés des assemblages avec notamment une augmentation des vitesses de charge/décharge et une mobilisation accrue des matériaux actifs de cathodeThe evolution of energy consumption in recent decades has led to major changes in the design of autonomous electrical systems dedicated to either electrical or electronic applications. The present demand to build generators capable of delivering sufficient energy, with a guarantee of maximum safety, requires to explore new storage routes. The current lithium battery routes tend to show their limits, both strategic and environmental. In this context, the construction of new electrochemical systems implementing sodium opens the way of the lithium-free accumulators production. The need for ever more efficient batteries requires innovative designs, giving up the liquid path in favor of stronger solid systems. In addition, the miniaturization of electronics leads to a review of the size of the batteries, to micro-type batteries, for which the interest of a solid stack is no longer to demonstrate. Today, sulfur chalcogenide glasses allow access to ionic conductivities that suggest the possibility of a realization of all solid batteries, both in the form of micro batteries or massive batteries. A research effort has been made to formulate these chalcogenide glasses in order to obtain a maximum of ionic conductivity and properties allowing their use as electrolytes. The composition of these glasses highlights the interest of the different elements for such properties. The study of the electrolyte shaping by thin-film deposition (obtained by Radio Frequency Magnetron Sputering, RFMS) proves the feasibility of these all-solid sodium micro-batteries. Subsequently, the realization of massive all solid batteries required the synthesis of two cathode materials (NaCrO2 and Na [Ni0.25Fe0.5Mn0.25]O2) and two anode materials (Na15Sn4 and Na) thus allowing the implementation of four electrochemical stacks, all characterized as accumulators. Finally, the improvement of the interfaces thanks to a gel-polymer made it possible to improve the properties of the assemblies with notably an increase of the speeds of charge / discharge and an enhanced mobilization of the cathode active materials
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Difi, Siham. „Phosphates de type NASICON comme matériaux d'électrode pour batteries sodium-ion à haute densité d'énergie“. Thesis, Montpellier, 2016. http://www.theses.fr/2016MONTT212/document.
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Ce mémoire est consacré à l’étude des composites à base de phosphates de type NASICON comme matériaux d’électrode pour batteries sodium-ion : Na1+xFexTi2-x(PO4)3/C et Na1+xFexSn2-x(PO4)3/C avec 0 ≤ x ≤ 1. Ces composites ont été synthétisés par voie solide suivie d’une pyrolyse avec le saccharose. Ils sont constitués de particules ayant une porosité élevée et enrobées par du carbone conférant à l’électrode une bonne conductivité ionique et électronique. Les mécanismes réactionnels se produisant lors des cycles de charge-décharge ont été analysés en mode operando par diffraction des rayons X, spectroscopies Mössbauer du 57Fe et de 119Sn et spectroscopie d’absorption X. Pour les composites fer-titane, ces mécanismes sont essentiellement basés sur la diffusion des ions Na+ dans les canaux des phases cristallisées avec changements d’état d’oxydation des métaux. Pour les composites fer-étain, les mécanismes sont plus complexes incluant insertion, conversion conduisant à la destruction des phases NASICON, puis formation d’alliages NaxSn. Les meilleures performances électrochimiques ont été obtenues pour Na1,5Fe0,5Ti1,5(PO4)3/C avec un potentiel de fonctionnement de 2,2 V vs Na+/Na0. Même si ces deux familles de matériaux peuvent être utilisées à plus bas potentiel, les performances doivent être améliorées pour envisager leur application comme électrode négativeThis thesis is devoted to the study of phosphate based composites with NASICON type structure, that are used as electrode materials for sodium-ion batteries: Na1+xFexTi2-x (PO4)3/C et Na1+xFexSn2-x(PO4)3/C with 0 ≤ x ≤ 1. These composites were synthesized by solid state route followed by a pyrolysis reaction with sucrose. They consist of particles having high porosity and coated with carbon giving to the electrode good ionic and electronic conductivity. The reaction mechanisms occurring during charge-discharge cycles were analyzed in operando mode, by X-ray diffraction, 57Fe and 119Sn Mössbauer spectroscopies and X-ray absorption spectroscopy. For the iron-titanium composites, the mechanisms are essentially based on the diffusion of Na+ in the channels of the crystalline phases with changes of transition metal oxidation state. For iron-tin composites, the mechanisms are more complex including insertion, conversion leading to the destruction of the NASICON phases and then reversible formation of NaxSn alloys. The best electrochemical performances were obtained for Na1,5Fe0,5Ti1,5(PO4)3/C with an operating potential of 2.2 V vs. Na+/Na0. Although these two types of materials can be used at lower potential, the performances must be improved to consider their application as the negative electrode
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Wang, Luyuan Paul. „Matériaux à hautes performance à base d'oxydes métalliques pour applications de stockage de l'énergie“. Thesis, Université Grenoble Alpes (ComUE), 2017. http://www.theses.fr/2017GREAI031/document.
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Le cœur de technologie d'une batterie réside principalement dans les matériaux actifs des électrodes, qui est fondamental pour pouvoir stocker une grande quantité de charge et garantir une bonne durée de vie. Le dioxyde d'étain (SnO₂) a été étudié en tant que matériau d'anode dans les batteries Li-ion (LIB) et Na-ion (NIB), en raison de sa capacité spécifique élevée et sa bonne tenue en régimes de puissance élevés. Cependant, lors du processus de charge/décharge, ce matériau souffre d'une grande expansion volumique qui entraîne une mauvaise cyclabilité, ce qui empêche la mise en oeuvre de SnO₂ dans des accumulateurs commerciaux. Aussi, pour contourner ces problèmes, des solutions pour surmonter les limites de SnO₂ en tant qu'anode dans LIB / NIB seront présentées dans cette thèse. La partie initiale de la thèse est dédié à la production de SnO₂ et de RGO (oxyde de graphène réduit)/SnO₂ par pyrolyse laser puis à sa mise en oeuvre en tant qu'anode. La deuxième partie s'attarde à étudier l'effet du dopage de l'azote sur les performances et permet de démontrer l'effet positif sur le SnO₂ dans les LIB, mais un effet néfaste sur les NIB. La partie finale de la thèse étudie l'effet de l'ingénierie matricielle à travers la production d'un composé ZnSnO₃. Enfin, les résultats obtenus sont comparés avec l'état de l'art et permettent de mettre en perspectives ces travauxThe heart of battery technology lies primarily in the electrode material, which is fundamental to how much charge can be stored and how long the battery can be cycled. Tin dioxide (SnO₂) has received tremendous attention as an anode material in both Li-ion (LIB) and Na-ion (NIB) batteries, owing to benefits such as high specific capacity and rate capability. However, large volume expansion accompanying charging/discharging process results in poor cycleability that hinders the utilization of SnO₂ in commercial batteries. To this end, engineering solutions to surmount the limitations facing SnO₂ as an anode in LIB/NIB will be presented in this thesis. The initial part of the thesis focuses on producing SnO₂ and rGO (reduced graphene oxide)/SnO₂ through laser pyrolysis and its application as an anode. The following segment studies the effect of nitrogen doping, where it was found to have a positive effect on SnO₂ in LIB, but a detrimental effect in NIB. The final part of the thesis investigates the effect of matrix engineering through the production of a ZnSnO₃ compound. Finally, the obtained results will be compared and to understand the implications that they may possess
Bücher zum Thema "Sodium ion accumulators"
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Gluckman, Sir Peter, Mark Hanson, Chong Yap Seng und Anne Bardsley. Potassium in pregnancy and breastfeeding. Oxford University Press, 2015. http://dx.doi.org/10.1093/med/9780198722700.003.0022.
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Potassium is an important electrolyte involved in transmission of electrical signals for muscle contraction, nerve impulse transmission, and cardiac function. The fetus accumulates potassium throughout gestation, but little is known about maternal potassium balance during pregnancy. Conditions associated with pregnancy, such as severe vomiting or morning sickness, can cause potassium loss. Caffeine increases the renal excretion of potassium, and cases of hypokalaemia in pregnancy have been observed in women with heavy caffeine/cola consumption, resulting in extreme muscle fatigue. To date there is insufficient evidence to suggest that the potassium requirement is increased during pregnancy, although a small increase in intake is needed for lactation. Reduction of cardiovascular risk factors and bone loss may be assisted by increasing potassium intake and/or by dietary sodium reduction.
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Arroyo, Vicente, Mónica Guevara und Javier Fernández. Renal failure in cirrhosis. Herausgegeben von Norbert Lameire. Oxford University Press, 2015. http://dx.doi.org/10.1093/med/9780199592548.003.0247.
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A major event in liver cirrhosis is the development of a progressive deterioration of circulatory function due to splanchnic arterial vasodilation and impairment in cardiac function. This feature determines a homeostatic activation of the renin–angiotensin–aldosterone system, sympathetic nervous system, and antidiuretic hormone. The splanchnic microcirculation is resistant to the vasoconstrictor effect of these systems. Therefore, the homeostasis of arterial pressure in cirrhosis occurs in the extrasplanchnic, mainly renal circulation. The activation of these systems produces renal fluid retention, which accumulates as ascites, and water retention and dilutional hyponatraemia. In the latest phase of cirrhosis, when circulatory dysfunction is severe, renal vasoconstriction is intense and patients develop type 2 hepatorenal syndrome (HRS) and refractory ascites.Type 1 HRS is an acute and rapidly progressive renal failure that occurs in the setting of a precipitating event, commonly an infection. Patients with type 1 HRS also present with rapid deterioration of liver function (encephalopathy, jaundice) and relative adrenal insufficiency. The mechanism of this multiorgan failure is an acute deterioration in circulatory function due to both an accentuation of arterial vasodilation and of cardiac dysfunction.There is no specific test for the diagnosis of HRS. The most accepted diagnostic criteria are those proposed by the International Ascites Club which are based on the exclusion of other types of renal failure. The course of renal failure following treatment of the precipitating event of HRS is another important diagnostic feature.The treatment of choice of tense ascites in cirrhosis is paracentesis associated with intravenous albumin infusion. Moderate sodium restriction and diuretics (spironolactone alone or associated with furosemide) are subsequently given to prevent re-accumulation of ascites. Diuretics are the treatment of choice in patients with moderate ascites. Patients with type 2 HRS and refractory ascites (not responding to diuretics) could be treated by frequent paracentesis or by the insertion of a transjugular intrahepatic portosystemic shunt (TIPS).Terlipressin plus albumin is the treatment of choice in type 1 HRS
Konferenzberichte zum Thema "Sodium ion accumulators"
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Marquino, Wayne, Bharat Shiralkar und Shivakumar Sitaraman. „Mitigation of Anticipated Transients Without Scram in the ESBWR“. In 14th International Conference on Nuclear Engineering. ASMEDC, 2006. http://dx.doi.org/10.1115/icone14-89661.
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The ESBWR has robust ATWS performance due to the use of passive systems. The heatup of the suppression pool is minimized and the ATWS can be managed at high pressure. ATWS prevention/mitigation features of ESBWR include: 1) An Alternate Rod Insertion (ARI) system that utilizes sensors, logic and valves that are diverse and independent of the Reactor Protection System RPS, 2) Electrical insertion of Fine Motion Control Rod Drives (FMCRDs) that utilize sensors and logic which are diverse and independent of the RPS, 3) Automatic feedwater runback under conditions indicative of an ATWS, 4) An automatic Standby Liquid Control System (SLCS) with a capacity equivalent to 5.42E−3 m3/sec (86 gpm) of 13-weight percent sodium pentaborate solution. The boron is supplied by 2 accumulators and injection is triggered by Squib valves. The boron solution is piped inside the reactor to the core bypass, and discharges at several distribution points in high velocity jets. Several other ESBWR features help to mitigate an ATWS. The large steam volume in the chimney results in a reduced vessel pressurization rate. The isolation condensers terminate suppression pool heatup while there is still steam generation occurring in the core. Analysis with the TRACG computer code shows the ESBWR safety valve capacity is effective in limiting the pressure in the reactor vessel pressure. The automatic FW reduction reduces water level and core flow, which in turn reduces power to approximately one-quarter of the initial value. Finally the reactor is brought sub-critical by boron injection into the core bypass region from two Standby Liquid Control System accumulators. The results show that the mitigation systems are adequate to meet the acceptance criteria without operator action.
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Guo, Liancheng, und Andrei Rineiski. „Numerical Investigation of Corium Coolability in Core Catcher: Sensitivity to Modeling Parameters“. In 2018 26th International Conference on Nuclear Engineering. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/icone26-81841.
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To avoid settling of molten materials directly on the vessel wall in severe accident sequences, the implementation of a ‘core catcher’ device in the lower plenum of sodium fast reactor designs is considered. The device is to collect, retain and cool the debris, created when the corium falls down and accumulates in the core catcher, while interacting with surrounding coolant. This Fuel-Coolant Interaction (FCI) leads to a potentially energetic heat and mass transfer process which may threaten the vessel integrity. For simulations of severe accidents, including FCI, the SIMMER code family is employed at KIT. SIMMER-III and SIMMER-IV are advanced tools for the core disruptive accidents (CDA) analysis of liquid-metal fast reactors (LMFRs) and other GEN-IV systems. They are 2D/3D multi-velocity-field, multiphase, multicomponent, Eulerian, fluid dynamics codes coupled with a fuel-pin model and a space- and energy-dependent neutron kinetics model. However, the experience of SIMMER application to simulation of corium relocation and related FCI is limited. It should be mentioned that the SIMMER code was not firstly developed for the FCI simulation. However, the related models show its basic capability in such complicate multiphase phenomena. The objective of the study was to preliminarily apply this code in a large-scale simulation. An in-vessel model based on European Sodium Fast Reactor (ESFR) was established and calculated by the SIMMER code. In addition, a sensitivity analysis on some modeling parameters is also conducted to examine their impacts. The characteristics of the debris in the core catcher region, such as debris mass and composition are compared. Besides that, the pressure history in this region, the mass of generated sodium vapor and average temperature of liquid sodium, which can be considered as FCI quantitative parameters, are also discussed. It is expected that the present study can provide some numerical experience of the SIMMER code in plant-scale corium relocation and related FCI simulation.
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Tagami, Hirotaka, Songbai Cheng, Yoshiharu Tobita, Liancheng Guo, Bin Zhang und Koji Morita. „Development of Assessment Method for a Self-Leveling Behavior of Debris Bed and Analyses of Experiments“. In 2014 22nd International Conference on Nuclear Engineering. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/icone22-30290.
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When core melt occurs in severe accident in Sodium Cooled Fast Reactor (SFR), molten core material moves to the lower plenum in reactor vessel and fragmented by fuel coolant interaction. These fragmented particles, so called debris, accumulate on the structure surface to form debris bed. If the thickness of the debris bed exceeds the coolable thickness of the decay heat, boiling of sodium occurs inside the debris bed. It is found from past in-pile experiments that the sodium flow and boiling inside the debris bed caused by a decay heat planarize the debris bed to lower the debris bed thickness. This mechanism is called self-leveling of debris bed. In the accident sequence of SFR, when fuel debris locally accumulates beyond the coolable thickness, fuel debris remelts with decay heat and they cannot be retained in-vessel. However, it is expected that the debris bed thickness lowers the coolable thickness with self-leveling phenomenon and they can be safely retained in-vessel. This is why an appropriate assessment for self-leveling behavior is important for safety analysis of SFR with the object of safety cooling of fuel debris. Therefore, the object of this study is to develop new analytical methods to simulate unique phenomena in self-leveling behavior and implement it to SFR safety analysis code. The characteristic of self-leveling is that when the larger external forces caused by environmental fluids are larger than a threshold value, the debris bed is fluidized. The new methods are developed with assuming that the debris bed behaves as Bingham fluid from this feature. They are categorized into two main parts. The first part is particle interaction models to model the effect of particle-particle contacts and collisions. Particle pressure and particle viscosity related to particle-particle collisions and contacts, respectively, are applied to pressure and viscosity term in the particle momentum equation. The second part is a large deformation method, which simulates Bingham fluid characteristic of debris bed. This method numerically judges a onset of debris bed fluidization which depends on a shear stress strength. An experimental study of self-leveling behavior, in which the particle bed behavior driven by bubbles inflow from the bottom of bed in gas-solid-liquid three-phase flow was observed, is analyzed to validate the new methods. Simulation results well reproduced the transient changes of particle bed, whose elevation angle and form deformation becomes gradually small and obscure, respectively. Their dependencies on particle size and density are also well simulated with new methods. The assessment results show that these methods provide a basis to develop analytical methods of self-leveling behavior of debris bed in the safety assessment of SFRs.