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Mikula, Hynek. "Fázový diagram chladiva LiF-NaF-KF." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2010. http://www.nusl.cz/ntk/nusl-374735.
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In introduction this graduation theses discource about phase diagrams and thein fission. Next part is about concrete phase diagrams NaF – KF, NaF – LiF, KF – LiF. Their determination trough use of cooling surves and their specification trough use of numerical method. Conclusion contains proposal of method for concrete phase diagram of NaF – KF – LiF.
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Prins, Sara Natalia. "The AI-Pt-Ru ternary phase diagram." Diss., Pretoria : [s.n.], 2003. http://upetd.up.ac.za/thesis/available/etd-09192005-163724/.
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Epifano, Enrica. "Study of the U-Am-O ternary phase diagram." Thesis, Université Paris-Saclay (ComUE), 2017. http://www.theses.fr/2017SACLX084/document.
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Les isotopes de l’Américium sont les principaux contributeurs à la radioactivité des déchets nucléaires. Parmi les scénarios pour diminuer la toxicité des déchets, la transmutation dans les réacteurs à neutrons rapides utilisant des pastilles d’oxyde mixte (U,Am)O2 est une voie prometteuse. Dans ce cadre, la connaissance des propriétés thermodynamiques du système U-Am-O est essentielle pour prédire le comportement des pastilles (U,Am)O2 en conditions nominale et accidentelle. Cette thèse est dédiée à l’étude expérimentale d’oxydes mixtes (U,Am)O2 dans une large gamme de composition (7,5 % at. ≤ Am/(Am+U) ≤ 70 % at.). L’objectif est d’acquérir des données pour développer un modèle thermodynamique avec la méthode semi-empirique CALPHAD. Les résultats peuvent être classés en trois catégories : données structurales, données de diagramme de phase et données thermodynamiques. Pour la modélisation thermodynamique d’un système ternaire, l’optimisation des sous-systèmes binaires est nécessaire. Comme des questions restaient en suspens sur le système Am-O, le diagramme de phase Am-O a tout d’abord été étudié par diffraction des rayons X à haute température. L’existence d’un domaine de composition de la phase bcc AmO1.61 a été mis en évidence et la lacune de miscibilité dans la phase fluorite, proposée dans la littérature, n’a pas été confirmée. Grâce à ces nouveaux résultats, le modèle CALPHAD de Gotcu et al a été modifié. Dans une deuxième étape, des analyses structurales des dioxydes (U,Am)O2±x ont été effectuées par DRX, XAS et spectroscopie RAMAN. La DRX a permis de confirmer que tous les échantillons sont constitués d’une seule phase de structure fluorite. Le rapport O/M (avec M=U+Am) mesuré à température ambiante est inférieur à 2 ; la stabilité de l’Américium trivalent Am3+ a été mise en évidence. Celle-ci induit l’oxydation partielle de l’U4+ en U5+. Cette distribution de charge s’accompagne par la formation de défauts de l’oxygène complexes dans la structure fluorite. Lors de l’étude par DRX HT des oxydes mixtes sous air, il a été montré que la présence d’Am3+ stabilise la phase fluorite par rapport aux oxydes plus riches en oxygène (U4O9, U3O8). De nouvelles données de diagramme de phase ont été obtenues : des conodes dans les domaines biphasés M4O9-M3O8 and MO2+x-M3O8 et la solubilité de l’Américium dans les oxydes M4O9 et M3O8. L’étude du diagramme de phase U-Am-O a été poursuivie par la détermination des températures de solidus/liquidus des oxydes mixtes par une technique de chauffage laser, sous argon et sous air, et par la caractérisation des échantillons après fusion par SEM et XAS. La température de fusion des oxydes mixtes diminue avec une teneur croissante d’Américium (Am/(Am+U)) et d’oxygène (O/(Am+U)). Finalement, les propriétés thermodynamiques des oxydes (U,Am)O2±x ont été mesurées : les incréments enthalpiques par calorimétrie de chute et les pressions partielles des espèces gazeuses par Spectrométrie de Masse couplée à une cellule de Knudsen (KEMS). Une contribution d’excès de la capacité calorifique a été observée à haute température, attribuée à la réduction des oxydes (avec formation de lacunes d’oxygène). Les résultats de KEMS ont permis de déterminer une composition congruente de vaporisation à 2300 K, pour un rapport Am/(Am+U) de 0,6 et un rapport O/(U+Am) inférieur à 1,9. Finalement, la modélisation thermodynamique du système U-Am-O par la méthode CALPHAD a été abordée par la description de la phase fluorite. Un bon accord est obtenu entre le modèle et les données de potentiel d’oxygène pour l’oxyde (U0.5Am0.5)O2±x et de distribution des cations. De plus, le modèle permet de reproduire de façon satisfaisante les données de KEMS. En perspective de ce travail, la modélisation thermodynamique du ternaire sera étendue à la description des équilibres de phase mettant en jeu les oxydes M4O9, M3O8 et la phase liquideAmericium isotopes are the main contributors to the long-term radiotoxicity of the nuclear wastes, after the plutonium extraction. Among the reprocessing scenarios, the transmutation in fast neutron reactors using uranium-americium mixed oxide (U,Am)O2±x pellets seems promising. In this frame, the knowledge of the thermodynamics of the U-Am-O ternary system is of essential for the prediction of the behavior of (U,Am)O2 pellets and their possible interaction with the cladding, under normal and accidental conditions. This thesis is dedicated to the experimental investigation of U-Am mixed oxides on a wide range of Am contents (7.5 at.% ≤ Am/(Am+U) ≤ 70 at.%), with the aim to collect data for developing a thermodynamic model based on the semi-empirical CALPHAD method. The obtained results can be classified in three categories: structural, phase diagram and thermodynamic data. For the thermodynamic modeling of the ternary system, the assessment of the binary sub-systems is first required. As open questions still existed on the Am-O system, a first part of the work was dedicated to the study of the Am-O phase diagram by high-temperature (HT) XRD. The existence of a composition range of the bcc AmO1.61 phase was highlighted and the miscibility gap in the fluorite phase, proposed in the literature, was not found. Thanks to the new experimental data, the existing CALPHAD model of Gotcu et al. was modified. In a second step, structural investigations were performed on synthesized (U,Am)O2±x dioxides by coupling XRD, XAS and Raman spectroscopy. For all the compositions, the XRD confirmed the formation of a single fluorite structure. The O/M ratio (with M=U+Am) at room temperature was determined to be lower than 2; the stability of trivalent americium Am3+ in the dioxide solid solution was highlighted, which induces a partial oxidation of uranium from U4+ to U5+. This charge distribution, peculiar for a dioxide, is accompanied by the formation of complex oxygen defects in the fluorite structure. By a HT-XRD investigation of the mixed oxides under air combined with XAS characterization of the oxidized samples, it was shown that the presence of Am3+ leads to a stabilization of the dioxide fluorite phase toward the formation of oxides richer in oxygen, in comparison to the U-O system. New phase diagram data were obtained in the oxygen rich region at 1470 K: tie-lines in the M4O9-M3O8 and MO2+x-M3O8 domains were determined and the solubility of americium in the M4O9 and M3O8 oxides was estimated. The investigation of the U-Am-O phase diagram continued at higher temperature with the study of the solidus/liquidus transitions using a laser-heating technique, under argon and air, and post-melting characterizations conducted by SEM and XAS. The melting temperature of Am-U dioxides decreases with the increase of both the Am/(Am+U) and O/M ratios. Finally, thermodynamic properties of the U1-yAmyO2±x oxides were measured: enthalpy increments using drop calorimetry, partial vapor pressures by Knudsen cell effusion mass spectrometry (KEMS). An excess contribution to the heat capacity at high temperature was observed and this was attributed to the reduction of the dioxides at high temperature (formation of oxygen vacancies). The KEMS results lead to determine the congruent vaporization composition at 2300 K, for a Am/(Am+U) ratio of 0.6 and an O/M ratio lower than 1.9. Finally, the CALPHAD thermodynamic assessment of the U-Am-O system was started, by focusing the attention on the modelling of the fluorite phase. A good agreement between the model and the oxygen potential data for (U0.5Am0.5O2±x) and the cation distribution was achieved. Furthermore, the model is able to satisfactorily reproduce the KEMS data and hence the equilibrium between the dioxide and gas phase. For the perspectives of this work, the optimization of the thermodynamic model should be extended to describe the phase equilibria involving the M4O9, M3O8 oxides and the liquid phase
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Azevedo, Cesar R. de Farias. "Phase diagram and phase transformations in Ti-Al-Si system." Thesis, Imperial College London, 1996. http://hdl.handle.net/10044/1/1278.
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Horrocks, P. J. "Phase diagram and thermodynamics of the Ag-Cd-In ternary alloy system." Thesis, University of Manchester, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.508170.
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Kurosawa, Izumi. "Solid-Liquid Equilibrium in Multi Solute Systems." Diss., Georgia Institute of Technology, 2004. http://hdl.handle.net/1853/4993.
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Solid-liquid equilibrium in isomorphous amino acid systems has been investigated as a model for systems that form solid solutions. Solid- and liquid-phase compositions in L-valine + L-leucine, L-valine + L-isoleucine, and L-isoleucine + L-valine in water were measured over the entire range of solid composition, and it was shown (from mass balance and phase rule considerations) that these systems form solid solutions. The solid- phases resulting from isothermal and cooling crystallization experiments were also investigated using powder x-ray diffractometry which showed that homogeneous solid solutions could only be obtained in cooling crystallization experiments, whereas isothermal experiments generally produced inhomogeneous solids. This suggests that data reported in the literature from isothermal experiments may not represent true equilibrium values. Solid-phase activity coefficients were estimated using binary and ternary equilibrium data and the UNIFAC-Kuramochi model for liquid-phase nonidealities. The solid phases in the three systems investigated exhibited significant nonidealities that were correlated using the Margules model. The model parameters exhibited a linear relationship with the ratio of binary solubilities of the two solutes. Such simple relationship may be advantageous when solid-liquid equilibrium of thermally unstable solutes or components with unknown physical properties are crystallized.
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Dalgard, Elvi C. "Phase diagram studies in the Mg-rich corner of the Mg-Ce-In ternary system." Thesis, McGill University, 2007. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=100225.
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In the present study, dilute alloys in the Mg-rich corner of the Mg-Ce-In ternary system in the composition range 0 to 3% In and 0 to 1.5% Ce were synthesized. Cooling curve analysis was used to determine the liquidus points in order to construct the liquidus surface of the ternary phase diagram in the Mg corner. Energy dispersive spectroscopy (EDS), wavelength dispersive spectroscopy (WDS), and x-ray diffraction (XRD) techniques were used to examine phases present at the compositions studied. A thermal arrest presumed to represent a eutectic transformation was discovered at 580°C. Two new intermetallic compounds, designated tau and theta, were found. Trace silicon present in the alloys was found to concentrate in one of the intermetallic compounds.To further investigate these compounds, an induction furnace was used to synthesize alloys containing the concentrations of Ce and In seen in electron probe micro-analysis (EPMA) examinations of these compounds. The alloys were examined using the cooling curve technique and XRD, and proved to contain the compounds already observed with some variation in dissolved indium content. In addition, differential scanning calorimetry (DSC) was used to confirm the liquidus and solidus values determined using cooling curve analysis.
A diffusion couple with terminal compositions of pure Ce and a Mg-In alloy was prepared in order to determine the equilibrium phases present in the system between these two compositions at 390°C. EPMA was used to identify the zones obtained, and confirmed the presence of several Mg-Ce compounds with 1 at% dissolved indium, as well as a ternary compound corresponding to the theta compound found in the dilute alloys.
Finally, literature values and experimental data were used to calculate a preliminary ternary phase diagram using FACTSage, in collaboration with the CTRC at Ecole Polytechnique, in order to affirm the validity of the experimentally determined values as well as to project the diagram beyond the studied composition range.
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Zhang, Xin. "Experimental phase diagram studies on the Mg-Mn-Ce ternary system at Mg-rich corner." Thesis, McGill University, 2010. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=86547.
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The ternary Mg-Mn-Ce phase diagram was experimentally studied and thermodynamically calculated at the Mg-rich corner. More than twenty binary and ternary alloys were synthesized and heat-treated at both ambient and elevated temperatures. The microstructures and lattice parameters of the samples were studied via XRD, SEM/EDS and EPMA to determine phase equilibria. The ternary phase diagram was also calculated via thermodynamic calculation software FactSage. The results from both experiment and the assessment were compared and discussed. The binary phase diagrams were re-examined, especially the Mg-Ce system. In order to investigate the composition range of the intermetallic compounds Mg12Ce and Mg41Ce5, and to clarify data in the existing phase diagram, both the solid-liquid diffusion couple method and alloys synthesized with target phases were analyzed. The binary phase diagram study was also extended to the Ce-rich side of Mg-Ce system. A modified phase diagram was suggested to accommodate the stoichiometry of Mg11Ce, Mg39Ce5, and Mg3Ce. The experimental study on the ternary phase diagram was conducted on three isopleths: 0.6, 1.8 and 2.5wt% Mn, respectively, and Ce varied between 0 and 25wt%. Finally, the phase diagram calculation with FactSage program was conducted and the small disagreement between the modeling results and present experimental data were found.Le diagramme de phase ternaire Mg-Mn-Ce a été étudié expérimentalement et calculé thermodynamiquement à son extrémité riche en magnésium. Plus de 20 alliages binaires et ternaires ont été synthétisés et traités thermiquement à température pièce et températures élevées. La microstructure et les paramètres de maille des échantillons ont été étudiés via XRD, SEM/EDS et EPMA pour déterminer les phases à l'équilibre. Le diagramme de phase ternaire a aussi été calculé à l'aide du logiciel de calcul thermodynamique Factsage. Les résultats provenant des expériences ainsi que de l'évaluation thermodynamique ont été comparés et discutés. Les diagrammes de phase binaires ont été re-examinés, spécialement pour le système Mg-Ce. Dans le but d'évaluer l'étendue de composition des composés intermétalliques Mg12Ce et Mg41Ce5, ainsi que de clarifier les données des diagrammes de phase existants, les méthodes de couple de diffusion solide-liquide et de synthèse d'alliages aux phases ciblées ont été utilisés. L'étude du diagramme de phase binaire a été prolongée à l'extrémité riche en Ce du système Mg-Ce. L'étude expérimentale du diagramme de phase ternaire a été conduite sur trois isoplèthes: 0.6, 1.8 et 2.5wt% Mn, respectivement, et Ce a été varié entre 0 et 25wt%. Finalement, les calculs de diagramme de phase provenant du logiciel FactSage ont été fait et de petites divergences entre les résultats modélisés et ceux expérimentaux ont été observées.
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Herrero, Bocco Bernardo. "Assessment of the ternary phase diagram on the stoichiometric and hypo-stoichiometric U-Nd-O system." Thesis, université Paris-Saclay, 2020. http://www.theses.fr/2020UPASC008.
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Cette thèse concerne l’étude expérimental et la modélisation thermodynamique du comportement des combustibles avancés utilisés dans les centrales nucléaires actuelles et de future génération. L’objet de la thèse est plus précisément l’étude du système ternaire (U-Nd-O) et pour comparaison du système ternaire (U-Ce-O). Ce système est particulièrement représentatif des produits de fissions accumulés dans le combustible pour des taux de combustion élevés mais aussi du dopage initial du combustible avec des poisons neutroniques utilisés dans des combustibles à fort taux d’enrichissement en mesure d’espacer les arrêts réacteur. L’étude de ce système présente des défis importants en raison du conflit ouvert entre phénomènes thermodynamiques et cinétiques. Il s’agit en effet d’un système hors équilibre où la mise en ordre à longue porté des structures locales est frustrée par la faiblesse du transport cationique dans la plage de températures d’intérêt pour les applications. Au cours de cette thèse, une révision de la littérature existante a motivé la fabrication d’échantillons aux caractéristiques bien définies par des méthodes de métallurgie des poudres et par des méthodes de chimie douce aboutissant à un contrôle des distributions des dopants. Les résultats obtenus par de nombreuses techniques de caractérisation (DRX, MEB, MET, XAS) sur des échantillons traités thermiquement dans des conditions oxydantes ou réductrices ont permis une réévaluation critique des diagrammes de phases actuellement utilisés. Nous avons pu proposer des modifications aboutissant à un nouveau diagramme de phases permettant une meilleure connaissance des limites d’utilisation des combustibles dans des conditions de sécurité optimalesThis thesis concerns the experimental study and thermodynamic modeling of the behavior of advanced fuels used in current and future generation nuclear power plants. The subject of the thesis is more precisely the study of the ternary system (U-Nd-O) and for comparison purposes of (U-Ce-O). This system is particularly representative of the fission products accumulated in the fuel for high combustion rates but also of the initial atomic substitutions in the fuel by neutron poisons, used in nuclear fuels with high enrichment levels and capable of spacing out nuclear reactor outages. The study of this system presents significant challenges due to the open conflict between thermodynamic and kinetic phenomena. It is indeed an out of equilibrium system where the long-range ordering of local structures is frustrated by the negligible of atomic transport in the cation sublattice in the range of temperatures of interest for applications. During this thesis, a review of the existing literature motivated the manufacture of samples with well-defined characteristics by powder metallurgy methods and by soft chemistry methods leading to a control of dopant distributions. The results obtained by numerous characterization techniques (XRD, SEM, TEM, XAS) on samples treated thermally under oxidizing or reducing conditions have allowed a critical re-evaluation of the phase diagrams currently used. We have modelled a new phase diagram that includes new experimental results. This allows a better knowledge of the limits of use of nuclear fuels respecting optimal safety conditions
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Janowski, Mary Patricia. "An investigation of the high barium oxide portion of the BaO-Sc₂O₃-Al₂O₃ ternary phase diagram." Thesis, Georgia Institute of Technology, 1996. http://hdl.handle.net/1853/19414.
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Nicholson, Kelly Marie. "First principles calculations of thermodynamics of high temperature metal hydrides for NGNP applications." Diss., Georgia Institute of Technology, 2014. http://hdl.handle.net/1853/54027.
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In addition to their potential use at low to moderate temperatures in mobile fuel cell technologies, metal hydrides may also find application as high temperature tritium getterers in the U.S. DOE Next Generation Nuclear Plant (NGNP). We use Density Functional Theory to identify metal hydrides capable of sequestering tritium at temperatures in excess of 1000 K. First we establish the minimum level of theory required to accurately capture the thermodynamics of highly stable metal hydrides and determine that isotope effects can be neglected for material screening. Binary hydride thermodynamics are largely well established, and ternary and higher hydrides typically either do not form or decompose at lower temperatures. In this thesis we investigate anomalous systems with enhanced stability in order to identify candidates for the NGNP application beyond the binary hydrides. Methods implemented in this work are particularly useful for deriving finite temperature phase stability behavior in condensed systems. We use grand potential minimization methods to predict the interstitial Th−Zr−H phase diagram and apply high throughput, semi-automated screening methodologies to identify candidate complex transition metal hydrides (CTMHs) from a diverse library of all known, simulation ready ternary and quaternary CTMHs (102 materials) and 149 hypothetical ternary CTMHs based on existing prototype structures. Our calculations significantly expand both the thermodynamic data available for known CTMHs and the potential composition space over which previously unobserved CTMHs may be thermodynamically stable. Initial calculations indicate that the overall economic viability of the tritium sequestration system for the NGNP will largely depend on the amount of protium rather than tritium in the metal hydride gettering bed feed stream.
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Cao, Siwei. "Determination of the Fe-Cr-Ni and Fe-Cr-Mo Phase Diagramsat Intermediate Temperatures using a NovelDual-Anneal Diffusion-Multiple Approach." The Ohio State University, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=osu1377011410.
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Ahmad, Afandi. "Development of Fe-based Superalloys Strengthened by the γ'Phase." Kyoto University, 2020. http://hdl.handle.net/2433/259045.
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Bunk, Juliane K. G. "Verhalten funktionalisierter Nanopartikel an Grenzschichten mit Polymerbürsten." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2012. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-97359.
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Die vorliegende Arbeit liefert einen Beitrag zum Verständnis der komplexen Wechselwirkungen zwischen Nanopartikeln und Polymeren in dünnen Schichtsystemen. Dazu wurden in einem geeignetem Modellsystem drei verschiedene Einflussparameter auf die Nanopartikelverteilung im Polymer und zwischen einer hydrophilen und einer hydrophoben Grenzfläche analysiert. Für eine erste Abschätzung der Verträglichkeit der einzelnen Komponenten wurden Wechselwirkungsparameter, binäre und ternäre Phasendiagramme ermittelt. Die experimentelle Charakterisierung der Nanopartikelverteilung erfolgte mittels Rasterkraftmikroskopie, Rasterelektronenmikroskopie und Transmissionselektronenmikroskopie. Die erhaltenen Ergebnisse wurden mit denen der theoretischen Vorbetrachtungen verglichen um herauszufinden, ob Vorhersagen zur Nanopartikelverteilung in einem Polymer möglich sind. In dieser Arbeit konnte gezeigt werden, dass die Nanopartikelverteilung im Polymer mit den untersuchten Parametern gezielt beeinflusst werden kann.
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Chan, Hin Chung Stephen. "Co-crystal screening of poorly water-soluble active pharmaceutical ingredients. Application of hot stage microscopy on curcumin-nicotinamide system and construction of ternary phase diagram of fenbufen-nicotinamide-water co-crystal system." Thesis, University of Bradford, 2009. http://hdl.handle.net/10454/4253.
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Curcumin is the major phenolic diarylheptane derivative in Curcuma longa and has been reported to possess pharmacological activities. Unfortunately this compound suffers from poor bioavailability and rapid neutral-alkaline degradation. Co-crystal of curcumin is one option under exploration, motivated by the fact that a number of active pharmaceutical ingredient (API) co-crystals with improved dissolution have recently been synthesized. Hence, co-crystallization technique highlights an alternative means to improve the performance of curcumin.
Within our work evidences for a co-crystal was ascertained from DSC, Kofler hot stage screening and PXRD, and all confirmed a new crystal phase could have been formed between curcumin and a co-crystallizing agent, nicotinamide. We report that re-crystallization step essentially aids the purification of commercial curcumin, a herbal based actives. Otherwise the prevalence of a new crystal phase in solvent-mediated co-crystallization will be significantly reduced.
Besides, phase diagram is an effective tool for the study of solubility behaviours in co-crystal system. In order to acquire related techniques, fenbufen, a poorly water soluble drug, was selected. The result showed the huge difference in solubility between fenbufen and nicotinamide lead to difficulty in the construction of phase diagram.
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Martine, Milena. "Na-Sb-Sn-based negative electrode materials for room temperature sodium cells for stationary applications." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2017. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-226494.
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The implementation of energy storage systems in the current electrical grid will increase the grid's reliability and e ciency. Room temperature sodium batteries are seen as potential technology, especially to assist renewable energy generation sources. Currently, suggested negative electrode materials, however, are still not satisfactory for practical use in terms of fabrication costs, gravimetric /volumetric energy densities, cyclability, and irreversible capacity losses occur at the rst cycle. The literature describes various strategies that enhance the specific capacity and/or the cyclability of negative electrode materials but all involve increasing the fabrication costs due to the chosen synthesis or the complexity of the electrode's design. Furthermore, strategies, that reduce the irreversible capacity loss at first cycle, are not discussed. In this present experimental research work, presodiating bulk metallic negative electrode materials prior to cycling, prepared via a simple, cheap and easy-to-scaleup synthesis route, is introduced as a new strategy to improve the cyclability and to effectively reduce the first cycle irreversible capacity loss. Electrochemical and structural experiments were carried out to investigate sodiumtin-antimony powders. Presodiating mechanically bulk Sn-Sb negative electrode materials e ectively reduces the irreversible capacity loss at first cycle and enhances the specific capacity when compared to the non-presodiated powder, while the proper choice of electrode composite and electrolyte formulation improves the cycle life of the electrodes. The enhancement of the electrochemical properties of the presodiated NaSnSb powder, composed of the ternary phase Na5Sb3Sn and an unknown ternary phase crystallising in a hexagonal setting P6, is associated with the stabilisation of the SnSb as desodiation product. Presodiating bulk SnSb negative electrode material is a viable strategy to reduce the first cycle irreversible capacity loss, alleviating the volume changes. With an optimised system, this approach may be extended to other negative electrode materials, reducing the fabrication costs of high capacity negative electrode materials for room temperature sodium batteries. Presodiated NaSnSb negative electrode material may be combined with non-sodiated positive electrode material, such as sulphur to develop competitive room temperature sodium-sulphur batteriesDie Implementierung von Energiespeichersystemen im bereits bestehenden Stromnetz ist eine der Lösungen, um die Zuverlässigkeit und die Effizienz des Netzes zu nutzen. Raumtemperatur Natrium-Batterien gelten als erfolgsversprechende Technologie insbesondere zur Unterstützung erneuerbarer Energieerzeugungsquellen. Jedoch sind die naheliegenden negativen Elektrodenmaterialien für eine praktische Anwendung hinsichtlich Herstellungskosten, gravimetrischer oder volumetrischer Energiedichte, Zyklenfestigkeit und irreversiblen Kapazitätsverlusten im ersten Zyklus noch nicht zufriedenstellend. Die Literatur beschreibt verschiedene Strategien, die die spezifische Kapazität und / oder die Zyklenfestigkeit von negativen Elektrodenmaterialien verbessern. Diese führen jedoch alle zu einer Erhöhung der Herstellungskosten aufgrund der gewählten Synthese oder des Designs der komplexierten Elektrode. Darüber hinaus werden Strategien zur Reduzierung des irreversiblen Kapazitätsverlusts im ersten Zyklus nicht erörtert. Diese experimentelle Forschungsarbeit präsentiert mit Natrium angereicherte metallische negative Elektrodenmaterialien vor der Wechselbeanspruchung/dem periodischen Durchlaufen, die durch einen schlichten, billigen und einfach zu skalierenden Syntheseweg hergestellt wurden, als eine neue Strategie zur Verbesserung der Zyklenfestigkeit und zur wirksamen Verringerung des irreversiblen Kapazitätsverlusts im ersten Zyklus. Elektrochemische und strukturelle Experimente wurden durchgeführt, um mit Natrium angereichertes Zinn-Antimon-Pulver zu untersuchen. Die mechanischen mit Natrium angereichertes Sn-Sb-negativen Elektrodenmaterialien verringert effektiv den irreversiblen Kapazitätsverlust im ersten Zyklus und erhöht die spezische Kapazität im Vergleich zu dem ohne Natrium angereicherte Pulver, während die richtige Wahl der Elektrodenzusammensetzung und der Elektrolytformulierung die Lebenszyklus der Elektroden verbessert. Die Verbesserung der elektrochemischen Eigenschaften des mit Natrium angereicherten NaSnSb-Pulvers, bestehend aus der ternären Phase Na5Sb3Sn und einer unbekannten ternären Phase, die in einer hexagonalen Aufbau P6 kristallisiert, ist mit der Stabilisierung des Enddesodiationsproduktes beim periodischen Zyklus verbunden, wobei das intermetallische SnSb nach Rekristallisation vorliegt. Mit Natrium angereicherte SnSb negativen Elektrodenmaterialien sind eine tragfähige Strategie zur Verringerung des irreversiblen Kapazitätsverlustes im ersten Zyklus, die Volumenänderungen abschwächen. Mit einem optimierten System kann dieser Ansatz auf andere negative Elektrodenmaterialien erweitert werden um die Herstellungskosten von negativen Elektrodenmaterialien mit hoher Kapazität für Raumtemperatur-Natrium-Batterien zu verringern. Mit Natrium angereichertes NaSnSb-negatives Elektrodenmaterial kann mit nicht mit Natrium versetztem positivem Elektrodenmaterial wie Schwefel kombiniert werden, um realisierbare Raumtemperatur Natrium-Schwefel-Batterien zu entwickeln
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Cerba, Philippe. "Étude d'alliages base niobium pour applications à hautes températures." Nancy 1, 1993. http://www.theses.fr/1993NAN10006.
Full textAbstract:
Cette étude visant à développer des matériaux pour des applications à hautes températures s'est intéressée à la recherche de nouveaux alliages base niobium et à l'optimisation d'un revêtement protecteur de siliciures pour alliages de niobium existants. La recherche de nouveaux alliages a été entreprise avec le souci d'élaborer des structures biphasées a2-b2 semblables à celles des superalliages base nickel. Après avoir examiné sans succès le système nb-ti-al, les alliages biphasés mettant en équilibre a2 avec des structures voisines de b2 ont été trouvés dans des systèmes associant au niobium et a l'aluminium des métaux précieux comme le palladium et le ruthénium. Le revêtement protecteur pour alliages de niobium commerciaux est constitué de siliciures quaternaires, le procédé de cémentation activée permettant d'obtenir une qualité de surface remarquable
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Jarmar, Tobias. "High-Resolution Studies of Silicide-films for Nano IC-Components." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis : Univ.-bibl. [distributör], 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-4836.
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Daher, Habib. "Contribution a l'etude du diagramme de phase ag-sn-se." Paris 6, 1987. http://www.theses.fr/1987PA066325.
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Yang, Huaiyu. "Investigations intothe crystallization of butyl paraben." Licentiate thesis, KTH, Teknisk strömningslära, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-34051.
Full textAbstract:
In thisproject, solubility of butyl paraben in 7 puresolvents and 5 ethanol aqueous solvents has been determined at from 1 ℃to 50 ℃. Thermodynamic properties of butyl paraben have been measured by DifferentialScanning Calorimetey. Relationship between molar solubility of butyl paraben in6 pure solvents and thermodynamic properties has been analyzed. Thisrelationship suggests a method of estimating activity of solute at equilibrium fromcombining solubility data with DSC measurements. Then, activity coefficient accordingto the solubility at different temperatures can be estimated. Duringthe solubility measurements in ethanol aqueous solvents, it is found that whenbutyl paraben is added into aqueous solutions with certain proportion ethanol,solutions separates into two immiscible liquid layers in equilibrium. Water andethanol are primary in top layer, while the butyl paraben is primary in bottomlayer, but the solution turns to cloudy when two layers of solution are mixed. Theaim of this work was to present the phase behaviour of liquid-liquid-phaseseparation for (butyl paraben + water + ethanol) ternary system from 1 ℃ to 50 ℃at atmospheric pressure. Thearea of liquid-liquid-phase separation region in the ternary phase diagram increaseswith the increasing temperature from 10 ℃to 50 ℃. In thisstudy, more than several hundreds of nucleation experiments of butyl paraben havebeen investigated in ethyl acetate, propanol, acetone and 90% ethanol aqueoussolution. Induction time of butyl paraben has been determined at 3 differentsupersaturation levels in these solvents, respectively. Free energy ofnucleation, solid-liquid interfacial energy, and nuclei critical radius havebeen determined according to the classical nucleation theory. Statistical analysis ofinduction time reveals that the nucleation is a stochastic process with widevariation even at the same experiment condition. Butyl paraben nucleates most difficultlyin 90 % ethanol than in other 3 solvents, and most easily in acetone. The interfacialenergy of butyl paraben in these solvents tends to increasing with decreasemole fraction solubility in these solvents. Coolingcrystallizations with different proportions of butyl paraben, water and ethanolhave been observed by Focused Beam Reflectance Method, Parallel VirtualMachine, and On-line Infrared. The FBRM, IR curves and the PVM photos show someof the solutions appeared liquid-liquid phase separation during coolingcrystallization process. The results suggest that if solutions went throughliquid-liquid phase separation region during the cooling crystallizationprocess the distribution of crystals crystal was poor. Droplets from solutions withsame proportion butyl paraben but different proportions of water and ethanolhave been observed under microscope. Induction time of the droplets has been determinedunder the room temperature. Droplets from top layer or bottom layer of solutionwith liquid-liquid phase separation on small glass or plastic plates were alsoobserved under microscope. The microscope photos show that the opposite flows ofcloudy solution on the glass and the plastic plate before nucleation. The resultsof the cooling and evaporation crystallization experiments both revealed thatnucleation would be prevented by the liquid-liquid phase separation.QC 20110630
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Vu, Tuong-Dan. "Etude des diagrammes de phases ternaires La2O3 - Nb2O5 - (W/Mo)O3 et exploration des propriétés de conduction ionique." Thesis, Le Mans, 2016. http://www.theses.fr/2016LEMA1024/document.
Full textAbstract:
La2Mo2O9, premier composé de la famille LAMOX, est intéressant pour des applications comme électrolyte dans des piles à combustible car il présente une conductivité ionique élevée. Il a été découvert durant l'investigation du diagramme de phases de La2O3 -MoO3. Cela montre bien le rôle important de l'étude de diagrammes de phase dans la découverte de nouveaux matériaux qui est devenue un objectif majeur de nombreux chimistes du solide. Selon ce concept, les deux diagrammes de phases ternaires La2O3-Nb2O5-WO3 et La2O3-Nb2O5-MoO3 ont été explorés et analysés pour la première fois en utilisant la synthèse par voie solide. Les structures des échantillons obtenus ont été caractérisées par diffraction des rayons X et des neutrons sur poudre et par microscopie électronique en transmission tandis que leurs propriétés électriques ont été testées par spectroscopie d'impédance complexe sur des pastilles frittées.La majorité des zones mono-, bi- et tri-phasées de ces deux diagrammes ont été définies. Plus particulièrement, les structures de deux nouvelles phases La3NbWO10 et La5NbMo2O16 ont été résolues ab-initio. La connaissance des structures des 2 nouveaux composés a permis une meilleure approche du diagramme de phase ternaire. D'une part, la mailleLa3NbWO10 est une sur structure de la maille fluorine(2aF*2aF*2aF) avec un axe c allongé. En considérant la formulation La18Nb6W62O604 (Z = 6), on constate aisément que la structure présente 2 types de défauts:des lacunes anioniques et cationiques sur les sites des atomes d'oxygène et de lanthane. D'autre part, la phaseLa5NbMo2O16 est un isotype du composé Pr5Mo3O16. Sa maille correspond aussi à une surstructure fluorine. Elle cristallise dans un système cubique (a = 11.22 Å) avec le groupe d'espace rare Pn n. Ce composé est prometteur puisqu'il présente une conductivité par les ions oxyde proche de celle de La2Mo2O9 à basse températureLa2Mo2O9, the first compound in the LAMOX family, is interesting for its applications as electrolytes in fuel cells because it presents a high ionic conductivity. It was discovered during the investigation of La2O3 - MoO3phase diagram. That shows the important role of phase diagram study in the discovery of new materials which has become a major objective of many solid chemists.In this concept, two ternary phase diagrams of La2O3-Nb2O5-WO3 and La2O3-Nb2O5-MoO3 were explored and analyzed for the first time using the solid-state synthesis. The structures of the obtained samples were characterized by the powder X-ray and neutron diffraction and by the transmission electronic microscopy. Besides, their electric properties were tested by the complex impedance spectroscopy onsintered pellets.As results, most of the mono-, bi-, tri-phase zones in the title phase diagrams have been defined. Particularly, during the phase-diagram investigation, the structures of two new phases La3NbWO10 and La5NbMo2O16 were ab-initio resolved. Firstly, the La3NbWO10 cell is asuperstructure of a fluorine (2aF*2aF*2aF) with the lengthened c axis. Considering the La18Nb6W62O604(Z = 6) formulation, we can easily note that the structure presents 2 types of defaults: cationic and anionic vacancies. Secondly, the La5NbMo2O16 phase is isotype of Pr5Mo3O16 compound. Its cell is also a fluorine superstruture. It crystallized in a cubic system (a = 11.22Å) with the space group Pn n. The compound is promising because it presents an oxygen conductivity comparable to that of La2Mo2O9 at low temperature
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Strach, Michal. "In situ studies of uranium-plutonium mixed oxides : Influence of composition on phase equilibria and thermodynamic properties." Thesis, Aix-Marseille, 2015. http://www.theses.fr/2015AIXM4044.
Full textAbstract:
En raison de leurs propriétés chimiques et physiques, les oxydes mixtes d'uranium et de plutonium sont considérés comme combustibles pour les réacteurs nucléaires de quatrième génération. Dans ce cadre, des études expérimentales complémentaires sont nécessaire, notamment pour mieux comprendre les phénomènes mis en jeu lors de la fabrication ou sous irradiation. L'objet de ce travail est d'étudier le diagramme de phase U-Pu-O dans une large gamme de composition et de températures afin d'améliorer notre connaissance de ce système. La plupart des expériences ont été réalisées par diffraction des rayons X en fonction de la température. La contrôle in situ de la pression partielle en oxygène a permis de faire varier la stœchiométrie en oxygène dans le matériau. L'approche expérimentale a été couplée avec la modélisation thermodynamique par la méthode CALPHAD afin de mieux dimensionner les expériences et interpréter les résultats. Cette méthodologie a permis d'améliorer notre connaissance des équilibres de phase dans le système U-Pu-ODue to their physical and chemical properties, mixed uranium-plutonium oxides are considered for fuel in 4th generation nuclear reactors. In this frame, complementary experimental studies are necessary to develop a better understanding of the phenomena that take place during fabrication and operation in the reactor. The focus of this work was to study the U Pu–O phase diagram in a wide range of compositions and temperatures to ameliorate our knowledge of the phase equilibria in this system. Most of experiments were done using in situ X-ray diffraction at elevated temperatures. The control of the oxygen partial pressure during the treatments made it possible to change the oxygen stoichiometry of the sample, which gave us an opportunity to study rapidly different compositions and the processes involved. The experimental approach was coupled with thermodynamic modeling using the CALPHAD method, to precisely plan the experiments and interpret the obtained results. This approach enabled us to enhance the knowledge of phase equilibria in the U–Pu–O system
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Marchand, Jean-Pierre. "Relaxation magnétique nucléaire dans les solutions ternaires de polyacrylonitrile ou de polyacrylonitrile-co-méthallylsulfonate de sodium : détermination et caractérisation du diagramme de phases." Grenoble 1, 1993. http://www.theses.fr/1993GRE10193.
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Ce travail concerne l'etude des proprietes des solutions de polyacrylonitrile (pan) et des copolymeres d'acrylonitrile et de methallylsulfonate de sodium observees a l'equilibre ou hors equilibre thermodynamique. Utilisees dans la fabrication de membranes de dialyse renale, ces solutions ont ete explorees par rmn a une echelle d'espace caracteristique des processus physiques (cristallisation, demixtion) responsable des proprietes de permeabilite de ces membranes. Le pan et son copolymere presentent en solution un diagramme de phases typiques d'un polymere semi-cristallin; les conditions d'etablissement de la transition de phase solide-liquide et de la transition liquide-liquide ont ete precisees pour des solutions en solvant binaire dmf-eau equimolaire. La presence de charges ioniques sur la chaine polymere provoque un elargissement du domaine de la demixtion; cet effet a ete modelise dans le cadre de description des solutions proposees par flory. La cinetique de mise en ordre de ces polymeres en solution peut etre decrite comme un processus gouverne par une nucleation heterogene et sporadique, sans etape de croissance; cette cristallisation conduit a la formation de domaines ordonnes dont la taille moyenne a ete evaluee a l'aide de donnees thermodynamiques. Les membranes de dialyse renale realisees a partir de ces solutions peuvent etre decrites comme des gels physiques composes de domaines ordonnes interconnectes par des chaines polymeres a l'etat amorphe. La presence de ces domaines gouverne les proprietes de permeabilite et de selectivite de ces membranes
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Koot, Dwayne Jonathan. "Strategic pre-clinical development of Riminophenazines as resistance circumventing anticancer agents." Thesis, University of Pretoria, 2012. http://hdl.handle.net/2263/24163.
Full textAbstract:
Cancer is responsible for upward of 13% of human deaths. Contemporary chemotherapy of disseminated cancer is often thwarted by dose limiting systemic toxicity and by multi-drug resistance (MDR). Riminophenazines are a novel class of potential anticancer agents that possess a potent multi-mechanistic antineoplastic action. Apart from their broad action against intrinsic, non-classical resistance, Riminophenazines inhibit the action of Pgp and hypothetically all ABC transporters demonstrating their great utility against classical MDR. Considering that combination chemotherapy is the norm, the vision directing R&D efforts was that Riminophenazines could be used with benefit within many standard chemotherapeutic regimes. The strategic intent of this project was to attain improved therapeutic benefit for patients through gains in both pharmaco dynamic and pharmacokinetic specificity for cancer cells over what is currently available. Tactically, this was driven through the use of synergistic Fixed-Ratio Drug Combinations (FRDC) encapsulated within tumour-targeting Nanoparticulate Drug Delivery Systems (NDDS). Long-term aims of this R&D project were to: 1) Screen FRDC of clofazimine (B663) and the lead derivative (B4125) with etoposide, paclitaxel and vinblastine for synergistic drug interactions in vitro. 2) Design, assemble and characterize a novel nanoparticulate, synergistic, anticancer co-formulation. 3) Evaluate the in vivo safety and efficacy of the developed product/s in accordance with international regulatory guidelines. Using the median effect and combination index equations, impressive in vitro synergistic drug interactions (CI<1) were shown for various FRDC of the three standard chemotherapeutics tested (etoposide, paclitaxel and vinblastine) in combination with either B663 or B4125 against MDR neoplastic cell cultures. Considering in vitro results and with the view to advance quickly to clinical studies, the already approved clofazimine (B663) was elected as the combination partner for paclitaxel (PTX). Considering the potency and wide action of PTX, a novel coformulation (designed to circumvent drug resistance) has the potential to greatly impact upon virtually all cancer types, particularly if selectively delivered through innovative delivery systems and loco-regional administration. A passively tumour targeting, micellular NDDS system called Riminocelles™ that encapsulates a synergistic FRDC of B663 and PTX has been designed, assembled using thin film hydration methods and characterized in terms of drug loading, particle size, zeta potential, CMC and drug retention under sink conditions. An acute toxicity and a GLP repeat dose toxicity study confirmed Riminocelles to be well tolerated and safe at clinically relevant dosages whilst Taxol® (QDx7) produced statistically significant (P<0.05) weight loss within 14 days. The same study demonstrated statistically significant (P<0.05) tumour growth delays superior to that of Taxol at an equivalent PTX dosage of 10 mg/kg. Importantly, all components (amphiphiles and drugs) used in assembly of Riminocelles are already individually approved for medicinal use - this promotes accelerated development towards advanced clinical trials and successful registration. Although these results are very promising (outperforming Taxol), this system was however found in a pharmacokinetic study to suffer from in vivo thermodynamic instability due to the high concentration (abundance) of albumin present in plasma. For this reason, in vivo longevity within circulation, permitting passive tumour accumulation was not fully realized. A second NDDS called the RiminoPLUS™ imaging system was additionally developed. This lipopolymeric nanoemulsion system has successfully entrapped Lipiodol® Ultra fluid (an oil based contrast agent) within the hydrophobic core of a monodisperse particle population with a size of roughly 100 nm and a stability of one week. This formulation is therefore thought capable of CT imaging of tumour tissue and drug targeting after either intravenous or loco-regional injection. In vivo proof of the imaging concept is warranted. The results of this study serve to highlight the great potential of in vitro optimized synergistic FRDC against drug resistant cancers. Lipopolymeric micelles are an effective way to formulate multiple hydrophobic drugs for intravenous administration and present a means by which cancer can be readily targeted; provided that the delivery system possess the prerequisite in vivo stability and surface attributes. Further experiments exploring synergistic drug and biological combinations as well as “intelligent” NDDS actively guided through specific molecular recognition are called for.Thesis (PhD)--University of Pretoria, 2012.
Pharmacology
unrestricted
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Huaiyu, Yang. "Crystallization of Parabens : Thermodynamics, Nucleation and Processing." Doctoral thesis, KTH, Teknisk strömningslära, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-122228.
Full textAbstract:
In this work, the solubility of butyl paraben in 7 pure solvents and in 5 different ethanol-water mixtures has been determined from 1 ˚C to 50 ˚C. The solubility of ethyl paraben and propyl paraben in various solvents has been determined at 10 ˚C. The molar solubility of butyl paraben in pure solvents and its thermodynamic properties, measured by Differential Scanning Calorimetry, have been used to estimate the activity of the pure solid phase, and solution activity coefficients. More than 5000 nucleation experiments of ethyl paraben, propyl paraben and butyl paraben in ethyl acetate, acetone, methanol, ethanol, propanol and 70%, 90% ethanol aqueous solution have been performed. The induction time of each paraben has been determined at three different supersaturation levels in various solvents. The wide variation in induction time reveals the stochastic nature of nucleation. The solid-liquid interfacial energy, free energy of nucleation, nuclei critical radius and pre-exponential factor of parabens in these solvents have been determined according to the classical nucleation theory, and different methods of evaluation are compared. The interfacial energy of parabens in these solvents tends to increase with decreasing mole fraction solubility but the correlation is not very strong. The influence of solvent on nucleation of each paraben and nucleation behavior of parabens in each solvent is discussed. There is a trend in the data that the higher the boiling point of the solvent and the higher the melting point of the solute, the more difficult is the nucleation. This observation is paralleled by the fact that a metastable polymorph has a lower interfacial energy than the stable form, and that a solid compound with a higher melting point appears to have a higher solid-melt and solid-aqueous solution interfacial energy. It has been found that when a paraben is added to aqueous solutions with a certain proportion of ethanol, the solution separates into two immiscible liquid phases in equilibrium. The top layer is water-rich and the bottom layer is paraben-rich. The area in the ternary phase diagram of the liquid-liquid-phase separation region increases with increasing temperature. The area of the liquid-liquid-phase separation region decreases from butyl paraben, propyl paraben to ethyl paraben at the constant temperature. Cooling crystallization of solutions of different proportions of butyl paraben, water and ethanol have been carried out and recorded using the Focused Beam Reflectance Method, Particle Vision and Measurement, and in-situ Infrared Spectroscopy. The FBRM and IR curves and the PVM photos track the appearance of liquid-liquid phase separation and crystallization. The results suggest that the liquid-liquid phase separation has a negative influence on the crystal size distribution. The work illustrates how Process Analytical Technology (PAT) can be used to increase the understanding of complex crystallizations. By cooling crystallization of butyl paraben under conditions of liquid-liquid-phase separation, crystals consisting of a porous layer in between two solid layers have been produced. The outer layers are transparent and compact while the middle layer is full of pores. The thickness of the porous layer can reach more than half of the whole crystal. These sandwich crystals contain only one polymorph as determined by Confocal Raman Microscopy and single crystal X-Ray Diffraction. However, the middle layer material melts at lower temperature than outer layer material.QC 20130515
investigate nucleation and crystallization of drug-like organic molecules
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Kotchi, Kouadio Pierre. "Contribution à l'étude thermodynamique des liquides métalliques à fortes interactions." Aix-Marseille 1, 1986. http://www.theses.fr/1986AIX11056.
Full textAbstract:
Mesures, par calorimetrie de reaction directe, des enthalpies integrales et partielles de formation des systemes pb-se, sn-se et pb-se-sn. Determination des diagrammes de phases, des enthalpies de formation et de fusion des composes intermetalliques. Analyse du comportement thermodynamique de formation des liquides ternaires pb-se-sn a partir des parametres d'interactions binaires
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Bououdina, Mohamed. "Étude d'alliages et d'hydrures dérivés des phases de laves ZrCr2(1-x)M2x (M=éléments 3d et molybdène) : Synthèse, études structurale et thermodynamique en relation avec les propriétés de stockage de l'hydrogène." Grenoble 1, 1995. http://www.theses.fr/1995GRE10056.
Full textAbstract:
Preparation des alliages par induction dans un four hf. Stabilisation des phases par traitements thermiques. Hydrogenation par synthese solide-gaz sous pression. Caracterisation structurale par diffraction aux rayons-x et aux neutrons. Etude des diagrammes p-c-t (pression, composition et temperature). Pour ce faire, un nouveau systeme de controle et de regulation du systeme d'analyse thermogravimetrique completement automatise et assiste par ordinateur a ete mis au point. Modelisation: calcul de la chaleur de formation des solutions solides a partir d'un modele theorique adapte a nos systemes. Ceci nous a permis de discuter la stabilite des phases des alliages et la stabilite des hydrures
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Baret, Guy. "Étude thermodynamique et expérimentale de mélanges d'oxydes à basse température de fluage pour l'électronique." Grenoble INPG, 1989. http://www.theses.fr/1989INPG0003.
Full textAbstract:
A partir des mesures par atd et diffraction de rayons x et des donnees bibliographiques sur les diagrammes de phase binaires d'oxydes tels que sio::(2), b::(2)o::(3), p::(2)o::(5), gao::(2), as::(2)o::(3), calcul de diagrammes de phases ternaires et quaternaires. En utilisant les mesures de temperature de transition vitreuse et de fluage, proposition des systemes sio::(2)-b::(2)o::(3)-geo::(2) et sio::(2)-b::(2)o::(3)-as::(2)o::(3) comme oxydes de planarisation dans les circuits integres
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Chen, Jung-Yi, and 陳俊毅. "Assessment of Ag-Al-Pd Ternary Phase Diagram." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/08233527304747450058.
Full textAbstract:
碩士國立中山大學
材料與光電科學學系研究所
102
For the ternary phase diagram manufacturing process，often the preparation of 30 to 50 different composition ratio of the alloy, and the heat treatment takes a long time to complete the entire phase diagram. The experiment is based on diffusion couple processes to fabricate aluminum ternary alloy 500 ℃ low temperature phase diagram; Quite effective in reducing supplies in favor of precious metal alloys, and shorten the aging time, and for the Ag-Al-Pd tenary phase diagram to do research.
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Wang, Xiao Zhao. "Experimental investigation of the Mg-Al-Ca ternary phase diagram." Thesis, 2005. http://spectrum.library.concordia.ca/8837/1/MR14315.pdf.
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This work focuses on the experimental investigation of the ternary Mg-Al-Ca system using Differential Scanning Calorimetry (DSC), X-ray Diffraction (XRD) and metallographic techniques. Twenty one samples were chosen in the critical regions with the guidance of the phase diagrams developed by thermodynamic modeling. The DSC has permitted real time measurement of the temperature and enthalpy of the phase transformations. The experimental results were compared with thermodynamic calculations using the phase assemblage diagrams and vertical sections. The thermodynamic calculations are consistent with the experimental results in some samples, especially in the solidus temperature, whereas discrepancy was observed in several cases especially in the liqudus phase transformation temperature. This suggests that Mg-Al-Ca system should be reoptimised considering the new experimental findings. Nevertheless, the phases that were identified with the XRD and metallographic techniques show agreement with thermodynamic modeling. One of the invariant transformations predicted by thermodynamic modeling was verified experimentally and found to occur at 512{493}C and the composition is close to 10.8 at.% Ca 79.5 at.% Mg and 9.7 at.% Al. In this study, a new phase region was found close to the Mg-Al side and a new ternary solid solution (Mg 2 Ca) was confirmed
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Chen, Kuo-min, and 陳國敏. "Phase Diagram Study of Zr-Al-Si ternary system at 800 ℃." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/6fgmx2.
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Gallino, Isabella. "Phase diagram, thermal stability, and high temperature oxidation of the ternary Cu-Ni-Fe system." Thesis, 2003. http://hdl.handle.net/1957/29582.
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Due to the aluminum industry demands, a large effort has recently been devoted
to the development of special alloys to be used as inert anodes for a newly designed
aluminum reduction cell. The implementation of this new technology aims at the
replacement of the graphite anodes that have been used for over 100 years in aluminum
smelting, which would reduce fossil carbon consumption, and eliminate the emission of
carbon dioxide and of perfluorocarbons. Ternary alloys containing copper, nickel, and
iron have been the subject of the research activities.
The present research focused on the stability of the Cu-Ni-Fe alloys at high
temperatures in oxidizing and fluoridating environments. The experimental methods
included thermodynamic calculations of the phase diagram ('Thermocalc'), optical
microscopy and microprobe microstructural and chemical investigations (EMIPA-WDS),
small-angle neutron scattering (SANS), differential thermal analysis (DTA), and air-oxidation
studies.
The results have led to the optimization of the Cu-Ni-Fe ternary phase diagram
and to an extensive study of the thermodynamics and kinetics of the spinodal
decomposition and discontinuous reactions occurring during ageing as a function of alloy
composition.
The oxidizing reactions occurring in air at high temperatures at the surface of the
alloys have been also discussed in terms of thermodynamic and kinetic laws. The phase
formation in a fluorine containing environment as encountered in an aluminum
electrolytic cell is predicted using principles of physical chemistry.Graduation date: 2004
Best scan available. Figures in original document are very dark and have a moray pattern.
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Wang, Ziheng. "PSEUDO-TERNARY PHASE DIAGRAMS OF A DRUG DELIVERY SYSTEM." Thesis, 2009. http://hdl.handle.net/10012/4385.
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The purpose of this research was to develop the pseudo-ternary phase diagrams for a model drug delivery system consisting of vitamin E (model drug) + soybean oil + surfactant + co-surfactant (anhydrous glycerol) + water. The model drug (vitamin E) was loaded in the oil phase. The effects of different surfactants (pure and mixed) on the phase diagram, especially the microemulsion region, were investigated. The influence of drug loading level on the phase diagram was also determined. The surfactants studied were Tween 20, Tween 80, Cremopher EL, and their mixtures. The size (area) of the microemulsion region of the phase diagram was found to be dependent on the type of surfactant used and the loading level of drug (vitamin E).
The phenomenon of phase inversion from W/O microemulsion to O/W microemulsion was also investigated for the drug delivery system consisting of soybean oil (0% w/w Vitamin E loading or 30% w/w Vitamin E loading) + Tween 80 + anhydrous glycerol + water. The inversion of phases was detected by observing changes in the viscosity of the system.
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Huang, Po-chun, and 黃柏鈞. "Phase diagram study of Cu-Ti-Sn ternary system at 700 °C." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/6a2s6q.
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Jain, T. A., and 簡廷安. "Experimental Investigation of the Si-Ge-Ti Ternary Phase Diagram and Diffusion Behaviors." Thesis, 1998. http://ndltd.ncl.edu.tw/handle/66694115266994865361.
Full textAbstract:
碩士國立中央大學
化學工程學系
86
In this thesis, the Si-Ge-Ti ternary isotherm at 900 oC was determined by using metallography, x-ray diffraction, and electron microprobe. The main objective is to provide the necessary thermodynamic information for designing contact materials in SiGe devices. In the second part of this thesis, the diffusion behaviors of Si-Ge-Ti system were studied. The objective is to provide the kinetic information for understanding the reactions between Ti and SiGe.In this study, it was confirmed that at 900 oC TiSi2 and TiGe2 form a continuous solid solution with the C54 crystal structure. It was also shown that, other than Ti(Si1-yGey)2 and Si1-xGex, there is not any binary or ternary phase within the Si-Ge-TiGe2-TiSi2 trapezoid. Between the Ti(Si1-yGey)2 and Si1-xGex single-phase field is the Ti(Si1-yGey)2-Si1-xGex two-phase region. The tie- lines for the Ti(Si1-yGey)2-Si1-xGex two-phase region were determined. The tie-lines tilt slightly toward the TiSi2 and Ge corners presumably because the enthalpy of formation for TiSi2 is slightly more negative than that of TiGe2. In other words, at equilibrium the silicon to germanium atom ratio is larger in the Ti(Si1-yGey)2 phase than in the Si1-xGex phase (x>y). The isotherm determined here was then used to explain the complicated phenomena observed during the reaction between Ti and Si1-xGex. A strategy of forming stable contact to SiGe device was devised based on the thermodynamic information obtained in this study.It was also confirmed that at 900 oC and 1100 oC Ti5Si3 and Ti5Ge3 form a continuous solid solution with the D88 crystal structure. The lattice parameters of Ti5(Si1- wGew)3 were determined. The homogeneity ranges of Ti3(Si1-vGev), Ti(Si1-qGeq), Ti5(Si1-pGep)4, and Ti6(Si1-rGer)5 solid solution were also determined. In the second part of this thesis, Ti/Ge binary diffusion couple experiment at 800 oC was performed. Two of the three thermodynamically stable phases, Ti6Ge5 and TiGe2, were identified. However, Ti5Ge3, which is also stable at 800 oC, was not detected. Reasons for Ti5Ge3 to be missing were discussed.
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Bolcavage, Ann. "A thermodynamic and experimental determination of the CU-IN-PB ternary phase diagram." 1994. http://catalog.hathitrust.org/api/volumes/oclc/32067284.html.
Full textAbstract:
Thesis (Ph. D.)--University of Wisconsin--Madison, 1994.Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 209-216).
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Lai, Hung-En, and 賴弘恩. "Ternary Phase Diagram of Hydrogen Storage Alloys:Ti-V-Mn and Ti-Cr-Mn." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/w7yej2.
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碩士國立臺灣科技大學
化學工程系
95
In this study, the phase equilibrium of hydrogen storage alloys Ti-Cr-Mn and Ti-V-Mn, have been studied by experimental method. The relevant studies reported that the hydrogen storage alloys formed by Ti, V, Cr, and Mn metals have a very well hydrogen storage capacity. The phase diagrams of these metal systems were investigated in this study. The metals, Ti, V, Cr, and Mn, have a melting point higher than 1200℃. Therefore, arc-melter was utilized to prepare these samples. Then the samples were annealed at 900℃ for 5 weeks to reach equilibrium. Afterward, the microstructures were observed by SEM and EPMA, and the composition was analyzed by WDS. Samples in powder were analyzed by X-ray diffractometer for studying the crystal structures and the lattice parameters. In this study, we did not discover any ternary compounds. All of solid solutions, like (β-Ti), (V), (Cr), (Mn), with BCC structures have a large solubility. Furthermore, (β-Ti) and (V) formed a wide-range continuous solid solutions in Ti-V-Mn phase diagram. The Laves phase has rapid hydrogen absorption-desorption rate and high storage capacity with large solubility as well. Furthermore, TiMn2 and β-TiCr2 formed a single continuous phase in the phase diagram of Ti-Cr-Mn. In our phase diagram, the Laves phase and (β-Ti, V) phase formed the largest number of ternary equilibrium with other phases. Therefore, these phases are the most easily exist and stable ones in Ti-Cr-Mn and Ti-V-Mn phase diagrams compared to the other phases.
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-Huang, Chang Gi, and 黃成吉. "Experimental investigation of the Si-Ge-Co ternary phase diagram and diffusion reactions." Thesis, 1999. http://ndltd.ncl.edu.tw/handle/76258942435620189851.
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碩士國立中央大學
化學工程研究所
87
In this thesis, the Si-Ge-Co ternary isotherm at 800oC was re-determined by X-ray diffraction、electron-probe microanalysis and metallography. The main objective is to provide the necessary thermodynamic information for designing contact materials for applications in SiGe devices. In the second part of this thesis, the diffusion behaviors of Si-Ge-Co system were studied. The objective is to provide the kinetic information for understanding the reaction between Co and SiGe. It was shown that despite rather long annealing times, the silicon-germanium phase did not come fully into homogeneity in composition. It was caused by severe segregation and slow diffusion in silicon-germanium. It was also shown that Co5Ge7 is not stable at 800 oC and it decomposes at 797 oC. The composition of Si1-xGex that can be in equilibrium with CoSi2 was determined to be x=0.78. The tie-lines in the two-phase equilibrium between Si1-xGex and Co(Si1-yGey) were also determined. The isotherm determined here was then used to explain the complicated phenomena observed during the reaction between Co and Si1-xGex. A strategy of forming stable contact to SiGe device was devised based on the thermodynamic information obtained in the study. The cobalt-rich region of the Si-Ge-Co ternary phase diagram was also established. These results together with those mentioned above fully describe the Si-Ge-Co ternary phase equilibria at 800oC. In the second part of this thesis, Co/Ge binary diffusion couple experiment at 800oC was performed. Two of the three thermodynamically stable phases, Co3Ge2 and CoGe, were identified. However, CoGe2, which is also stable at 800 oC , was not detected. Reason for CoGe2 to be missing was probably the large difference in interdiffusion coefficients. The Co/CoGe binary diffusion couple experiment at 800oC was also performed. The reaction was very rapid. It was found that voids near the Co/Co3Ge2 interface caused by thermal stress between Co and Co3Ge2.
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Apata, Ayodeji Oluwatoyin. "An investigation of the C-Ni-V ternary phase diagram and development of abrasion-resistant alloys." Thesis, 2016. http://hdl.handle.net/10539/23082.
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A thesis submitted to the Faculty of Engineering and the Built Environment, University of the Witwatersrand, in fulfilment of the requirements for the degree of Doctor of Philosophy in Engineering (Metallurgy and Materials Engineering).
Johannesburg, March 2014This study investigated the C-Ni-V ternary phase diagram and identification of possible abrasive-resistance alloys. Twenty-four alloys were made from the elemental components and were arc-melted under an argon atmosphere, using Ti as an oxygen-getter. These alloys were analysed in both the as-cast condition, and after annealing for 1000oC and water quenching. Microstructural characterization was carried out in a SEM with EDX, and was done to confirm the phases. The results were used to plot a solidification projection and all binary phases extended into ternary, except for ~Ni8V, ~NiV3 and ~V2C which were not found, due to the sample compositions chosen. The extensions of the binary phases were: ~Ni3V: ~15 at.% C; ~Ni2V: ~20 at.% C; σ′: ~18 at.% C; (Ni): ~27 at.% C; ~V8C7: ~2 at.% Ni; ~V6C5: ~2 at.% Ni and ~VC: ~2 at.% Ni. The liquidus surface was derived, and three ternary invariant reactions were identified. The isothermal section at 1000oC was also constructed. Hardness of the alloys was studied in both conditions. Alloys with (Ni) (188-402HV5) were found to be ductile with low hardness. Alloys containing (V), ~Ni3V and ~Ni2V were identified as hard phases (533-1052 HV5). Alloys with σ′ phase were very hard (1065-1266 HV5) extremely brittle with cracks. Fracture toughness of the C-Ni-V alloys 0.9-5.2 (MPa.m-1/2) were comparable with ceramics 0.5-5.3(MPa.m-1/2). The wear behaviour of the alloys was characterized by sliding the carbide alloys against a Cr-steel ball in a pin-on-disc configuration. There were several co-existing wear mechanisms: abrasion, adhesion and the formation of a thin tribolayers. The wear coefficients for a 10N contact load after a sliding wear path of 300m varied between 0.1 x 10-6and 7.6 x 10-6(mm3/Nm), which was not as good as WC-Co hard metals, but close.
MT2017
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Jen, I.-Lun, and 任毅倫. "Phase diagram of ternary Zn-Sb-Ga system and Thermoelectric properties of Ga doped Zn4Sb3 alloys." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/5wu289.
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碩士國立中山大學
材料與光電科學學系研究所
107
In order to cope with the global warming and energy sustainability, the development of thermoelectric (TE) materials has grown extremely in recent years. The p-type β-Zn4Sb3 attracts great attention in the application of middle temperature thermoelectric generators.The addition of Gallium (Ga) in the Zn4Sb3 leads to the power factor (PF) increasing with two times in selective Ga-doped Zn4Sb3 which is grown crystal by the Bridgman method. At 623 K, the maximum solubility of Gallium in Zn4Sb3 under the thermally equilibrium state is less than 4 at.%Ga, as suggested by the isothermal section of ternary Zn-Sb-Ga system. As a result, the Ga-substituted (Zn1-xGax)4Sb3 achieves high figure of merit zT of 1.36 at 673 K as a result of the reduced κ~0.70 (W/mK) and enhanced PF~1.3 (mW/mk2) compared with the undoped Zn4Sb3 (zT~0.8), showing an ideal demonstration of phonon-glass-electron-crystal (PGEC).
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Chen, Ling Chieh, and 陳令婕. "Interfacial reactions at the Ag-Sb joints in the PbTe thermoelectric devices and Ag-Ni-Sb ternary phase diagram." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/26592100125588874564.
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碩士國立清華大學
化學工程學系
104
Thermoelectric devices convert waste heat directly into electricity, enhance energy usage efficiencies, and have attracted a lot of research interests. The PbTe compound has good thermoelectric properties and is promising for thermoelectric devices in the temperature range of 300-600oC. Usually, there are many joints in a thermoelectric module. Because of their different application temperatures, different solders/brazes with different melting points are needed. Ag-Sb eutectic alloy, of which melting point is 485oC, is a promising candidate as the joining materials for the mid-temperature thermoelectric modules. Ni and Co are commonly used as barrier layers to prevent interfacial reactions between joining materials and thermoelectric materials. Therefore, the study in the interfacial reactions among thermoelectric material, barrier layer and joining material is crucial for the efficiencies and reliabilities of a thermoelectric device. Phase diagrams contain phase equilibria information and are fundamentally important for understanding and illustration of interfacial reactions. This study thus includes the following discussions: (1) experimental determination of the Ag-Ni-Sb isothermal sections at 400oC and 550oC, (2) thermodynamic calculation of the Ag-Ni-Sb isothermal section, (3) Ni/Ag-Sb interfacial reactions at 350oC and 550oC, (4) Co/Ag-Sb interfacial reactions at 350oC and 550oC, and (5) Co/PbTe interfacial reactions at 350oC and 550oC. In this study, the metallographic analysis, compositions, and structures are determined by SEM, EPMA, and XRD. Similar results are found in the Ag-Ni-Sb isothermal sections at 400oC and 550oC. No ternary compounds are observed and all the binary compounds have very limited ternary solubilities. There are 7 tie-triangles at 400oC. The Ag3Sb+NiSb2+Sb, Ag+Ni5Sb2+NiSb, Ag+(Ni3Sb)+Ni5Sb2, and Ag+Ni+(Ni3Sb) tie-triangles have been experimentally determined. In addition, there are 9 tie-triangles at 550oC. The Sb+liquid+NiSb2, liquid+NiSb+NiSb2, liquid+Ag3Sb+NiSb, and Ag+Ni+(Ni3Sb) tie-triangles have been experimentally determined. Two intermetallic phases are observed in the Ni/Ag-Sb couples reacted at 350oC, and they are NiSb and NiSb2. Ni3Sb, Ni5Sb2 and NiSb are formed in the Ni/Ag-Sb couples reacted at 550oC. According to the phase formation sequence and morphologies, it is concluded that Sb is the fastest diffusion species. One intermetallic phase, CoSb, is observed in the Co/Ag-Sb couples reacted at 350oC. Two intermetallic phases are found in the Co/Ag-Sb couples reacted at 550oC, and they are CoSb and CoSb3. According to the reaction microstructures, Sb is the fastest diffusion species. The IMCs in the Co/Ag-Sb couples are brittle. The Ag-Sb has good wetting toward the Ni substrate. The reaction rates of Ag-Sb eutectic alloys with Ni are comparable to those of commercial solders with Ni. Thus, Ni is a proper barrier layer for Ag-Sb eutectic alloy, and Ag-Sb eutectic alloy is a suitable braze for the mid-temperature thermoelectric modules. No intermetallic phase is in the Co/PbTe couples at 350oC and 550oC. The wettability between Co and PbTe is good. Co thus can be a suitable barrier layer for PbTe.
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Lin, Chih-Hung, and 林志鴻. "Prediction of the Metallic Glass Formation Regions for the Cu-Ni-Ti Ternary System Using the CALculation of PHAse Diagram (CALPHAD) Method." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/6q8s6q.
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碩士國立臺灣科技大學
材料科學與工程系
106
So far, many researchers developed the Cu-based metallic glass with critical size until centimeter-scale. However, known alloy systems are basically limited to Cu–Zr-based alloys and the development of new shape memory BMG composites is essential to broaden the knowledge and to improve the properties of these composites. Very recently, new BMGs have been found in the Cu-Ni-Ti ternary system near the pseudo-binary eutectic (L ⇔ TiCu + TiNi). Fully glassy rods of 1 and 1.5 mm diameter were obtained, which also exhibit good mechanical properties In this study focused on the calculation of phase diagram (CALPHAD) to predict the metallic glass region. The re-assessment of Cu-Ni-Ti ternary phase diagram have established well by using the parameters from the pieces of literature. After establishing the reasonable Cu-Ni-Ti thermodynamic database to describe each phase, the binary and ternary phase diagram can be plotted. The thermodynamic parameters were also used for predicting the metallic glass regions by combining the metastable phase diagram which suppressed intermetallic compounds (IMCs) phases, liquid miscibility gap, and spinodal curve. The predicted region have consistency with the experimental data and experimental result from the pieces of literature in bulk metallic glass alloys which done in this study.
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Hermana, Gita Novian, and Gita Novian Hermana. "Prediction of the Metallic Glass Formation Regions for the Cu-Ti-Zr Ternary System by the Calculation of Phase Diagram (CALPHAD) Method." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/76460552727775676558.
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碩士國立臺灣科技大學
材料科學與工程系
105
Copper based amorphous alloy have a great attention in the recent years because of its high glass forming ability (GFA), lower cost, and good mechanical properties. Cu-Zr amorphous alloys are quite popular among the other amorphous alloys. Titanium (Ti) can be added to substitute some Zirconium (Zr) elements in Cu-Zr amorphous alloys to improve the mechanical properties as well as the glass forming ability. In this study focused on the calculation of phase diagram (CALPHAD) to predict the metallic glass region. In order to re-assessed the thermodynamic parameter, the experimental investigation of phase equilibria in Cu-Ti-Zr ternary system should be understand well. The phase equilibria of the Cu-Ti-Zr have made by arc melting method and annealed at 703 oC for 1440 hours and then quenched in icy water. The isothermal section have composed of 15 single phases which include the ternary phase-Cu2TiZr, 17 two-phases regions, and 17 three-phases regions, respectively. The CuTi2-CuZr2 phases form continuous solid solution and the ternary phases located in the central portion of this isothermal section. The re-assessment of Cu-Ti-Zr ternary phase diagram have established well. The thermodynamic parameters were used for predicting the metallic glass regions by combined the supressed intermetallic compounds (IMCs) phases, liquid miscibility gap, and spinodal curve. The predicted region have consistency with the experimental data and experimental result in bulk metallic glass alloys which done in this study.
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Paluch, Krzysztof J., T. McCabe, B. Müller-Bunz, O. I. Corrigan, A. M. Healy, and L. Tajber. "Formation and physicochemical properties of crystalline and amorphous salts with different stoichiometries formed between ciprofloxacin and succinic acid." 2013. http://hdl.handle.net/10454/14341.
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YesMulti-ionizable compounds, such as dicarboxylic acids, offer the possibility of forming salts of drugs with multiple stoichiometries. Attempts to crystallize ciprofloxacin, a poorly water-soluble, amphoteric molecule with succinic acid (S) resulted in isolation of ciprofloxacin hemisuccinate (1:1) trihydrate (CHS-I) and ciprofloxacin succinate (2:1) tetrahydrate (CS-I). Anhydrous ciprofloxacin hemisuccinate (CHS-II) and anhydrous ciprofloxacin succinate (CS-II) were also obtained. It was also possible to obtain stoichiometrically equivalent amorphous salt forms, CHS-III and CS-III, by spray drying and milling, respectively, of the drug and acid. Anhydrous CHS and CS had melting points at ∼215 and ∼228 °C, while the glass transition temperatures of CHS-III and CS-III were ∼101 and ∼79 °C, respectively. Dynamic solubility studies revealed the metastable nature of CS-I in aqueous media, resulting in a transformation of CS-I to a mix of CHS-I and ciprofloxacin 1:3.7 hydrate, consistent with the phase diagram. CS-III was observed to dissolve noncongruently leading to high and sustainable drug solution concentrations in water at 25 and 37 °C, with the ciprofloxacin concentration of 58.8 ± 1.18 mg/mL after 1 h of the experiment at 37 °C. This work shows that crystalline salts with multiple stoichiometries and amorphous salts have diverse pharmaceutically relevant properties, including molecular, solid state, and solubility characteristics.
Solid State Pharmaceutical Cluster (SSPC), supported by Science Foundation Ireland under grant number 07/SRC/ B1158.
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Chu, Jacquelene. "Linker-based Lecithin Oral Drug Delivery Systems." Thesis, 2012. http://hdl.handle.net/1807/33716.
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In this study, pharmaceutical-grade and food-grade linker-based lecithin self-emulsifying delivery systems (SEDS) were developed with a combination of lipophilic and hydrophilic linkers. These additives at suggested concentrations are safe for pharmaceutical and food applications. The ratio of surfactant lecithin and linkers in these systems was optimized to develop surfactant in oil preconcentrates. The preconcentrates containing different surfactant concentrations and oil were diluted with fed state simulated intestinal fluid to produce pseudo-ternary phase diagrams and to identify the formulations that produced self-emulsifying or self-microemulsifying delivery systems. Optimal SEDS preconcentrates were evaluated using a dialyzer model to simulate intestinal uptake. An uptake of 39.6 mg/cm2 for the pharmaceutical-grade SEDS was obtained within 72 minutes, which promises substantial improvement in the bioavailability of hydrophobic actives. The optimal uptake of 12.2 mg/cm2 for food-grade SEDS suggests enhancement in the bioavailability of omega-3 fatty acids.