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Two novel lithium host materials were investigated using structural and electrochemical analysis; the cathode material Li₂CoSiO₄ and the LiMO₂ class of anodes (where M is a transition metal ion). Li₂CoSiO₄ materials were produced utilising a combination of solid state and hydrothermal synthesis conditions. Three Li₂CoSiO₄ polymorphs were synthesised; β[subscript(I)], β[subscript(II)] and γ₀. The Li₂CoSiO₄ polymorphs formed structures based around a distorted Li₃PO₄ structure. The β[subscript(II)] material was indexed to a Pmn2₁ space group, the β[subscript(I)] polymorph to Pbn2₁ and the γ₀ material was indexed to the P2₁/n space group. A varying degree of cation mixing between lithium and cobalt sites was observed across the polymorphs. The β[subscript(II)] polymorph produced 210mAh/g of capacity on first charge, with a first discharge capacity of 67mAh/g. It was found that the β[subscript(I)] material converted to the β[subscript(II)] polymorph during first charge. The γ₀ polymorph showed almost negligible electrochemical performance. Capacity retention of all polymorphs was poor, diminishing significantly by the tenth cycle. The effect of mechanical milling and carbon coating upon β[subscript(II)], β[subscript(I)] and γ₀ materials was also investigated. Various Li[subscript(1+x)]V[subscript(1-x)]O₂ materials (where 0≤X≤0.2) were produced through solid state synthesis. LiVO₂ was found to convert to Li₂VO₂ on discharge, this process was found to be strongly dependent on the amount of excess lithium in the system. The Li₁.₀₈V₀.₉₂O₂ material had the highest first discharge capacity at 310mAh/g. It was found that the initial discharge consisted of several distinct electrochemical processes, connected by a complicated relationship, with significant irreversible capacity on first discharge. Several other LiMO₂ systems were investigated for their ability to convert to layered Li₂MO₂ structures on low voltage discharge. While LiCoO₂ failed to convert to a Li₂CoO₂ structure, LiMn₀.₅Ni₀.₅O₂ underwent an addition type reaction to form Li₂Mn₀.₅Ni₀.₅O₂. A previously unknown Li₂Ni[subscript(X)]Co[subscript(1-X)]O₂ structure was observed, identified during the discharge of LiNi₀.₃₃Co₀.₆₆O₂.

Les objectifs de ce travail de thèse étaient d’explorer de nouvelles voies pour l’amélioration des performances des accumulateurs Li/S, systèmes présentant de fortes densités d’énergie théorique dont les performances sont limitées par un mécanisme électrochimique incluant des intermédiaires solubles et réactifs. Ces intermédiaires induisent une faible efficacité coulombique et une perte importante de capacité au cours du cyclage. Plusieurs stratégies ont été mises en place pour créer une barrière de nature organique, au transport ou à la réactivité de ces polysulfures, tout en gardant une approche versatile et simple à mettre en œuvre. De bons résultats ont été obtenus en termes d’efficacité coulombique et de cyclabilité, notamment grâce à l’utilisation d’un matériau polymère capable d’interactions ioniques avec les intermédiaires soufrés. Le mécanisme de dépôt du lithium et de croissance dendritique a été également étudié, pour une compréhension plus complète du système. / The objectives of this thesis work were to explore new strategies to improve the performance of Li / S accumulators, systems exhibit with high theoretical energy densities whose performance is limited by an electrochemical mechanism including soluble and reactive intermediates. These intermediates induce a low coulombic efficiency and a significant loss of capacity during cycling. Several strategies have been evaluated to create a barrier of organic nature, which mitigate the transport or the reactivity of these polysulfides. The solutions explored are versatile and simple to implement. Good results have been obtained in terms of coulombic efficiency and cyclability, in particular through the use of a polymeric material enables to form ionic interactions with the sulfur intermediates. The mechanism of lithium deposition and dendritic growth has also been studied, for a more complete understanding of the system.

Made available in DSpace on 2009-11-18T19:00:49Z (GMT). No. of bitstreams: 0 Previous issue date: 2004 / The objective of this study is to propose a marketing relationship project to be used for Genyus Batteries in the construction of lasting relationships with relationship chain participants. To make it possible, concepts in the relationship marketing area are reviewed. Starting from the marketing plan suggested by Gordon (1999), was possible to verify wich strategies of this marketing plan were used or are being used by Genyus Batteries. The marketing plan used has eight phases: project for the project (O), client evaluation (1), 7 reference (2), enterprise evaluation (3), opportunities declaration (4), future state (5), business case (6) and change management and implementation (7); among these phases several relationship marketing strategies are analyzed to garantee their efficacy and to be certain the organization reaches its goals in the relationship formation and in the reach of differentiate position in the batteries market. It was certified that the studied organization doesn't have a relationship marketing project and, through this research, the organization will be able to use this plan in order to acquire efficacy in the relation marketing utilization. / O objetivo deste estudo é propor um plano de marketing de relacionamento para ser utilizado pela Genyus Baterias na construção de relacionamentos duradouros com os participantes da cadeia de relacionamentos. Para isto são revistos conceitos na área de marketing de relacionamento. Partindo do plano de marketing sugerido por Gordon (1999), foram verificadas quais estratégias deste plano foram ou estão sendo utilizadas pela Genyus Baterias. O plano de marketing utilizado possui oito fases: plano para um plano (fase O), avaliação do cliente (fase 1), referencial (fase 2), avaliação da empresa (fase 3), declaração de oportunidade (fase 4), estado futuro (fase 5), caso empresarial (fase 6) e administração de mudança e implementação (fase 7); dentro dessas fases são analisadas diversas estratégias de marketing de relacionamento para garantir a sua eficácia e para que a organização atinja seus objetivos na formação de relacionamentos e no alcance de uma posição diferenciada no mercado de baterias. Verificou-se que a organização estudada não possui um plano de marketing de relacionamento e, através desta pesquisa a organização poderá utilizar o plano criado para obter eficácia na utilização do marketing de relacionamento.

The diploma thesis is focused on the problems and relationship of specific language impairment and learning disabilities, as developmental disorders affecting not only speech and language, but also other areas influencing the educational process and school success of pupils. The introductory chapters are devoted to the theoretical definition of individual disorders with a focus on their terminology, etiology, symptomatology, diagnostics and therapy. Attention is also focused on the reciprocal context of specific language impairment and difficulties in reading, writing and orthography. The thesis is a comparative case study whose aim is to describe and compare the symptoms of the abovementioned disorders in a selected group of pupils of younger school age as reflected in basic school skills - reading and writing. The purpose of the thesis is to point out their interdependence and similarity in the field of education, but also certain specifics of each of the disorders depending on the individual peculiarities of each pupil.

The aim of the diploma thesis is to observe the influence of articular mobility through swimming lessons in younger school age children. Verified articulated mobility tests are used for these findings. Testing will take place twice, at the beginning and at the end of the swimming training over the course of one half-year. Testing will be done in two groups of children. The first group consists of students who participate in compulsory swimming lessons. The second group consists of children regularly taking part in swimming training in the swimming section in Brandýs nad Labem. In addition, people divided into swimmers and non-swimmers, and into boys and girls, were tested. The theoretical part of the thesis deals with the characteristics of motor abilities with focus on flexibility, characteristics of younger school age children and swimming training and swimming. The practical part consists of a description of the experiment and analysis of the results of the individual flexibility tests. The results of the work have shown that swimming is an appropriate means of developing flexibility. Improvements in all the groups studied were confirmed. KEYWORDS motor ability, flexibility, swimming, swimming training, younger school age, motor tests, student

Les accumulateurs nickel-hydrure métallique (NiMH) dominent actuellement le marché du stockage de l’énergie pour les véhicules hybrides. On estime à 1 milliard, le nombre de batteries NiMH produites chaque année. En fin de vie, le taux de recyclage de ces déchets électroniques reste faible, bien que la technologie NiMH contienne des quantités importantes de métaux onéreux et stratégiques. Deux grandes familles d’éléments chimiques coexistent sous forme de composés intermétalliques dans l’électrode négative: les métaux de transitions (TM) (Ni, Co, Mn et Fe) ainsi que les terres rares (REE) (La, Ce, Nd et Pr). Parmi les TM, le cobalt présente une criticité accrue. En effet, les minerais issus de réserves naturelles ne permettront pas de couvrir la demande croissante en cobalt liés au développement des technologies émergentes. Les REE produits à plus de 97 % en Chine sont au cœur des préoccupations de l’Union Européenne qui depuis 2010 pointe du doigt des techniques d’extractions dévastatrices pour l’environnement. C’est dans le but de répondre aux problématiques économiques et environnementales que le projet a été construit en associant l’entreprise de recyclage de batteries Recupyl® au laboratoire académique LEPMI grâce au financement du Labex CEMAM. L’objectif de ce travail est de proposer un procédé avec un faible impact environnemental pour le recyclage des métaux à partir de véritables accumulateurs NiMH. Pour cela, le remplacement de solvants volatiles organiques par des liquides ioniques, plus respectueux des principes de la ‘chimie verte’ sera étudié. En s’appuyant sur des procédés innovants d’extraction liquide-liquide et de récupération des éléments par hydrométallurgie et par électrochimie nous proposons une voie de valorisation des métaux présents dans ces batteries. / Nickel-metal hydride (NiMH) batteries are currently dominating the market of energy storage in hybrid electric vehicles. 1 billion cells are estimated to be produced each year. In their end-of-life, these electronical wastes exhibit low recycling rates, despite the fact that NiMH batteries contain high amounts of valuable and strategic metals. Two main metal families coexist as an intermetallic compound in negative electrodes: transition metals (TM) (Ni, Co, Mn and Fe) and rare earth elements (REE) (La, Ce, Nd and Pr). Among TM, cobalt exhibits the highest criticality rate. Indeed, natural ores will not cover the increasing cobalt demand linked to emerging technologies. REE produced at more than 97 % in China are at the centre of European Union’s preoccupations. To tackle economic and environmental issues, this project, supported by the labex CEMAM is a partnership between the company Recupyl® and the academic laboratory LEPMI. It aims at investigating on low environmental impact routes for the recycling of metals present in real spent NiMH batteries. This requires the replacement of volatile organic compounds by ionic liquids, respecting the principles of ‘green chemistry’. Based on innovative extraction and recovery processes of elements by hydrometallurgy and electrochemistry, we propose a flowsheet for the valorisation of metals from those batteries.

Orientador: Prof. Dr. Jorge Tomioka / Dissertação (mestrado) - Universidade Federal do ABC, Programa de Pós-Graduação em Engenharia Elétrica, 2014. / No contexto energético, as mudanças climáticas e as crescentes crises energéticas aumentaram as preocupações e as pesquisas na área de acumuladores de energia, visando alcançar melhorias no cenário energético e ambiental global. Ao mesmo tempo, a sociedade tornou-se dependente do consumo de energia elétrica, sendo que falhas no fornecimento não são permitidas. Portanto, observa-se a necessidade da energia ofertada ser de boa qualidade e, principalmente, não sofrer interrupções. Atrelado a esses fatores, a bateria de Magnésio ¿ Ar passou a ser considerada uma fonte promissora de energia elétrica, principalmente pela abundância de Magnésio (sétimo elemento mais presente no planeta), por não poluir o meio ambiente, ser barata e possuir energia especifica elevada. Essas características transformam esse acumulador em um potencial substituto para outras tecnologias. No entanto, a bateria demagnésio possui desvantagens que precisam ser vencidas por meio de pesquisas para alavancar o seu uso comercial massivo. Sob essa perspectiva, neste trabalho propõe-se o estudo da liga de magnésio AZ91 para aplicação em baterias de Magnésio ¿ Ar, por meio de ensaios de porosidade e de dureza, como também análise microestrutural e mensuração do potencial de circuito aberto e das curvas de polarização potenciodinâmica, utilizando-se uma célula eletroquímica de três eletrodos e um potenciostato em diferentes tempos de imersão da liga AZ91 na solução eletrolítica de NaCl 0,1 M. A porosidade da peça, observada no microscópio óptico com ampliação de 50 vezes, revelou que em cada fase de solidificação existem poros de tamanhos diferentes, com distribuição específica. Conforme o processo de resfriamento ocorre, nota-se a presença de poros maiores. Relacionado à porosidade, a dureza apresentou valores maiores na fase inicial de solidificação, onde a porosidade é menor. Por meio da análise microestrutural, foi possível verificar a presença de dendritas, com uma complexa dispersão de segunda fase na liga (alumínio), porosidades e inclusões. As medidas de potencial de circuito aberto indicam uma tendência de resistência à corrosão em temposmaiores de contato da amostra com a solução de NaCl. Não foi possível observar passivação aparente na amostra, nem pontos de corrosão localizada (pite) nas curvas de polarização potenciodinâmica. As variações no potencial de corrosão apontaram uma maior resistência à corrosão em tempos de imersão maiores; contudo, os valores estáveis de densidade de corrente de corrosão demonstram que a velocidade de corrosão permaneceu constante, sendo que a camada de óxido formada não contribuiu na proteção do material. Para a aplicação em baterias de magnésio, esses resultados conferem uma limitação da liga AZ91, pois a camada de óxido formada pode prejudicar o funcionamento do dispositivo em processos de descarga intermitente. As principais formas de controlar a eficiência da bateria de Magnésio ¿ Ar são por meio da composição da liga, da oxigenação, do pH, da temperatura e da concentração de sais NaCl no eletrólito. / In the energy sector, weather changes and rising energy crisis raised concerns and research in energy accumulators to achieve improvements in overall environmental and energy scenario. At the same time, society has become dependent on electricity consumption, so failures in supply are not tolerated. Therefore, the energy needs to have a good quality, and not suffer interruptions. Coupled to these factors, the battery Magnesium ¿ Air has been considered a promising source of electricity, mainly by the abundance of magnesium (seventh-most element present on the planet), not to pollute the environment, be cheap and have high specific energy. These characteristics transform this accumulator in a potential substitute for other technologies. However, the magnesium battery has disadvantages that need to be overcome through research to leverage their massive commercial use. From this point of view, this study proposes the characterization of magnesium alloy AZ91 for application in batteries Magnesium ¿ Air, testing the porosity and hardness, as well as microstructural analysis, and the measurement of the open potential circuit and the potentiodynamic polarization, in various immersion times using an electrochemical cell with three electrodes. The porosity of the part, observed in the optical microscope, revealed that at each stage of solidification, the pores have different sizes and distribution. As the cooling process occurs, could observe the presence of larger pores. Associated to the porosity, hardness values were higher in the initial phase of solidification, where the porosity was less. Through microstructural analysis was verified the presence of dendrites, with a complex dispersion of second phase in the alloy (aluminum), porosity and inclusions. The open potential circuit indicated a tendency for corrosion resistance in greater immersion time in the solution of NaCl. In all cases, the potentiodynamic polarization curves did not exhibit apparent passivity, or points of localized corrosion (pitting). The changes in corrosion potential showed greater resistance to corrosion in immersion times larger, however, the steady state values of corrosion current density demonstrated that the corrosion rate remained constant and the oxide layer formed did not protect the material. For use in magnesium batteries, these results provided a limitation of the AZ91 alloy, because the oxide layer can disturb the functioning of the device in cases of intermittent discharge. The main ways to control the battery efficiency Magnesium ¿ Air are through the alloy composition, oxygenation, pH, temperature and salt concentration of NaCl in the electrolyte.

Orientador: Prof. Dr. Caetano Rodrigues Miranda / Tese (doutorado) - Universidade Federal do ABC, Programa de Pós-Graduação em Nanociências e Materiais Avançados, 2015. / In this thesis, we explore computational materials science for energy technologies. More specifically, a multiscale computational methodology ranging from atomistic to mesoscopic methods was used to investigate the potential use of nanostructured materials for applications in: (i) hydrogen and fuel cells, (ii) rechargeable batteries, and (iii) oil recovery techniques. First principles simulations based on the Density Functional Theory were successfully employed to characterize and propose nanomaterials for hydrogen production and storage, fuel cells, and battery technologies. It was possible to understand fundamental properties that are essential to further development in these technologies, e. g. structural, electronic, catalytic and kinetic properties. The structural, energetic and electronic properties of layered metallic nanofilms of Pd, Pt and Au as catalysts for hydrogen and fuel cell applications were investigated. We have shown that Pd and Pt nanofilms are interesting systems, with improved catalytic activity for hydrogen, oxygen and ethanol. The evaluation of the electronic structure of such nanofilms shows the existence of a linear correlation between the d-band center and adsorption energies. The determination of such trends represents a significative contribution to the design of new and improved catalysts, since it is a valuable tool to predict the catalytic activity of nanofilms. Significant breakthroughs were also obtained when applying first principles calculations to battery technologies. The adsorption and di.usion properties of Li and Mg were investigated in transition metal dichalcogenide inorganic nanotubes. A high ion mobility is observed at the surface of MoS2 and WS2 nanotubes, which support the potential application of the use of such systems as additive electrode materials for high-rate battery applications. By using classical molecular dynamics calculations, the structural and di.usion properties of organic electrolytes could be determined and may help in the development of rechargeable batteries. Our simulations have demonstrated that mixture of ethylene carbonate and ethylmethyl carbonate present better di.usion properties as electrolyte in lithium ion batteries, since it is possible to obtain a good degree of dissociation associated to a good ionic conductivity. xvi Abstract In order to extent the nanoscale e.ects to the microscale, we also successfully propose a hierarchical computational protocol that combines molecular dynamics and mesoscopic lattice Boltzmann calculations. The e.ects of dispersed functionalized SiO2 nanoparticles in brine to the oil recovery process in a covered clay pore structure is explored. Molecular dynamics simulations have shown that the addition of functionalized nanoparticles to the brine solution reduces the interfacial tension between oil and brine. Followed by an increase of the contact angle. By mapping these results into lattice Boltzmann parameters, the oil displacement process in hydrophilic pore models was investigated. Our simulations indicate that the observed changes in the interfacial tension and wettability by the inclusion of SiO2 nanoparticles indeed improve the oil recovery process in a microscale, and seems to be a good alternative as injection fluids for enhanced oil recovery techniques. Thus, our proposed hierarchical computational protocol that combines molecular dynamics and lattice Boltzmann method simulations can be a versatile tool to investigate the e.ects of the interfacial tension and wetting properties on fluid behavior at both nano and micro scales. Although it is clear that the search and development of new advanced materials continues to be a key factor in energy technologies, the present thesis represent a significant contribution to understand the fundamental phenomena underlying hydrogen production and storage, fuel cells, batteries, and fossil fuel applications.

The aim of the work was to prove the correlation between the results of MABC-2 (Movement Assesment Battery for Children-2nd edition) and Iowa Brace test in ice hockey players aged 6 - 9 years. Testing was attended by 90 children who regularly attend hockey training HC Motor České Budějovice. Evaluations are based on quantitative results that are presented using tables. The resulting values were compared with the results of other authors. Subsequently, both test batteries were metered using the Spearman correlation coefficient and the Wilcoxon sequencing test. The correlation dependence has been demonstrated for all categories of bases. Wilcoxon's dependence was confirmed only in the younger categories (U6 and U7) in the two older categories was not confirmed. The work has shown that there is a correlation between the results of the MABC-2 test battery and the Iowa Brace test. Measurements took place at the Grünwald Primary School in České Budějovice