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See detailSynthèse et étude du composé Li4Ti5O12 comme électrode négative dans les accumulateurs Li-ion
Jamin, Claire ULg

Doctoral thesis (2014)

Electrical energy consumption has increased dramatically and its mode of consumption has diversified over the years, with the development of mobile energy storage devices such as lithium batteries. The ... [more ▼]

Electrical energy consumption has increased dramatically and its mode of consumption has diversified over the years, with the development of mobile energy storage devices such as lithium batteries. The present thesis is dedicated to the synthesis and study of the compound Li4Ti5O12 as negative electrode in Li-ion batteries. The main objective is the development of innovative synthesis techniques based on soft chemistry in order to control and study the effect of structural and microstructural parameters on the electrochemical properties of the compound. Because of its ability to intercalate/deintercalate Li+ ions in its structure without stress-generating volume changes of the structure, Li4Ti5O12 is considered as a so-called "zero-strain" electrode, favouring excellent cycling performance. Therefore, this compound appeared to us a most interesting candidate in this study. The first part of this work investigates a method involving the freeze-drying of a gel precursor followed by self-ignition. Hydroxypropylmethylcellulose is used as an additive and the synthesis of Li4Ti5O12 takes place in four steps : Gelling – Freeze-drying – self-ignition – Calcination. Ammonium nitrate was also added to the reactants to determine the impact on the self-ignition process and the consequences on the structure, microstructure and electrochemical properties of the compound. Indeed, a major issue usually encountered in self-ignition is controlling the amount of heat released, and therefore the temperature during self-ignition. These factors greatly influence the structural and microstructural properties of the compound. The results show that addition of ammonium nitrate leads to an excessive crystal growth which is unfavorable to electrochemical properties of the compound. In the second part of the thesis, the spray-drying method has been investigated using both a lab-scale and a pilot-scale equipment, to take into account possible developments on an industrial scale. For both devices, the influence of concentration on particle morphology was observed. The lab spray-dryer allowed us to obtain a convex to mushroom morphology. For the pilot spray-dryer, the morphologies vary from cauliflower to smooth hollow spheres, and can be further modified by addition of a carbonate source which decomposes during calcination. Depending on the particle morphology and its surface for intercalation of Li+ ions, the electrochemical performances have been improved, sometimes considerably. The drying temperature also affects the performance of the compound through the agglomeration rate of the particles. In conclusion, a wide panel of microstructures has been obtained by investigating two synthesis methods with various sets of experimental conditions. Although all these powders are Li4Ti5O12, there is a significant variation of their electrochemical performance and we have attempted to correlate these with particle morphology. Some prominsing results have been obtained and suggest that performance can be further improved through future work, on both fundamental and applied aspects. [less ▲]

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See detailÂgisme et jeunisme : conséquences trop méconnues …!
Adam, Stéphane ULg

Conference (2014, March 27)

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See detailLes fins du monde peuvent-elles faire littérature ? Exemplarités du récit dystopique
Stienon, Valérie ULg

Scientific conference (2014, March 27)

S’il est possible d’observer de nombreuses œuvres qui, depuis le XIXe siècle et particulièrement au tournant du XXe siècle, se présentent comme des fictions de fins du monde déclinant les situations ... [more ▼]

S’il est possible d’observer de nombreuses œuvres qui, depuis le XIXe siècle et particulièrement au tournant du XXe siècle, se présentent comme des fictions de fins du monde déclinant les situations-catastrophes, il est plus difficile d’appréhender ces textes en mots et en images comme un ensemble cohérent et de les associer à un genre littéraire particulier. Entre désignations d’époque et catégorisations rétrospectives, un corpus se dessine toutefois, qui développe ses propres caractéristiques internes et connaît une histoire éditoriale complexe. La communication propose de réfléchir aux modalités d’appartenance de ces « récits dystopiques » à l’histoire littéraire et aux critères possibles de leur rassemblement pour une étude poétique transversale. [less ▲]

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See detail« Shaping the future of migration and integration research : a flash-forward »
Martiniello, Marco ULg

Scientific conference (2014, March 27)

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See detailIssues related to protein fermentation in the intestines of pigs
Bindelle, Jérôme ULg

Scientific conference (2014, March 27)

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See detailPiété et impiété dans les rapports entre Grecs et étrangers
Delli Pizzi, Aurian ULg

Scientific conference (2014, March 27)

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See detailQuaternary rainforests of the Northern Congo Basin: contribution of charcoal analysis
Morin-Rivat, Julie ULg; Bremond, Laurent; Gillet, Jean-François ULg et al

Conference (2014, March 27)

In comparison with the wood charcoals uncovered in the soils of the temperate regions, charcoals from the tropical regions remain little studied yet, in particular those from the dense humid forests of ... [more ▼]

In comparison with the wood charcoals uncovered in the soils of the temperate regions, charcoals from the tropical regions remain little studied yet, in particular those from the dense humid forests of Central Africa. Here we aim at showing the interest of the analysis of soil charcoals so as to understand the current environments through some examples of taxonomical identifications conducted on charcoals sampled in several soil pits in Cameroon and in the Republic of the Congo. These charcoals were hand-split then observed under an incident light microscope. The anatomical features that are hold in the charcoals and described according to a standard method were compared to wood samples from the reference collection of the RMCA. Results demonstrated that the identified species are still present in the vegetal environment today and that only limited changes occurred over the past two millennia. Charcoal analysis can thus allow a better understanding of the past history of the forests in relationship with the ancient disturbances. The temporal and spatial framework of human settlements as well as the impact of the colonial period on the evolution of the forest is also discussed. [less ▲]

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See detailInvestir en Chine. Enjeux, Modalités d'investissement, Aspects fiscaux. (Organisation scientifique)
Richelle, Isabelle ULg

Scientific conference (2014, March 27)

La veille de l'arrivée en Belgique du Président de la République populaire de Chine, alors qu'un important accord d'investissements est en cours de négociation entre l'Union européenne et la Chine, une ... [more ▼]

La veille de l'arrivée en Belgique du Président de la République populaire de Chine, alors qu'un important accord d'investissements est en cours de négociation entre l'Union européenne et la Chine, une nouvelle convention fiscale nous liant à la Chine vient d'entrer en vigueur. L'objectif de ce colloque est de donner aux entreprises et à leurs conseils juridiques et fiscaux un ensemble de "clés" leur permettant de comprendre la Chine, afin d’optimaliser leurs investissements et d'en analyser de manière efficace les différentes problématiques fiscales. La réussite d'un investissement suppose en effet une bonne connaissance de ses interlocuteurs. La bonne application de la loi fiscale implique d'en appréhender les concepts sous-jacents. Différents acteurs ayant une expertise directe de la Chine nous font part de leur expérience. [less ▲]

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See detailDroit électoral et principe d'égalité. L'élection des assemblées législatives nationales en droit allemand, belge et britannique
Bouhon, Frédéric ULg

Doctoral thesis (2014)

The study concerns the election law and the equality principle in three European legal systems, i.e. the Federal Republic of Germany, the Kingdom of Belgium and the United Kingdom. In this framework, the ... [more ▼]

The study concerns the election law and the equality principle in three European legal systems, i.e. the Federal Republic of Germany, the Kingdom of Belgium and the United Kingdom. In this framework, the research is structured into two principal questions. I firstly wonder whether the election law guarantees equality among the governed people. Should the answer to that question be negative, I secondly check if the inequality can be legally justified in democratic systems. My thesis is a nuanced answer to these questions. The work shows that election law, considered under the scope of the equality principle, includes two categories of legislations which effect is opposed: some legal rules tend to distribute equally the faculty to influence the composition of the elected assemblies, while others tend to distribute unequally that faculty. Among the rules of the second category, I argue that the tendency to inequality can be partly legally justified by the purposes of these rules, but is also a mean – hardly justifiable in a democratic system – that helps persons and parties in government to remain in power. [less ▲]

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See detailRedefinition of Political and Social Thoughts during the Italian Wars: France and Burgundy
Dumont, Jonathan ULg

Scientific conference (2014, March 27)

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See detailProgramming of neuroendocrine self-tolerance in the thymus and its defect in the development of neuroendocrine autoimmunity
Geenen, Vincent ULg

Conference (2014, March 27)

The thymus may be compared to a computer highly specialized in the programming of central immunological self-tolerance. A unique thymus first appeared some 500 million years ago in cartilaginous fishes ... [more ▼]

The thymus may be compared to a computer highly specialized in the programming of central immunological self-tolerance. A unique thymus first appeared some 500 million years ago in cartilaginous fishes, at the same time or shortly after the emergence of the adaptive immune system. A new paradigm of neuroendocrine self-peptides has been proposed, together with the definition of neuroendocrine self. Neuroendocrine self-peptides are secreted by thymic epithelial cells (TECs) not according to the classic model of neurosecretion, but are processed for presentation by the thymic major histocompatibility complex (MHC) machinery. The autoimmune regulator (AIRE) gene/protein controls the transcription of neuroendocrine genes in TECs. Presentation of neuroendocrine self-peptides in the thymus is responsible for the clonal deletion of self-reactive T cells directed toward neuroendocrine antigens, which emerge during the random recombination of gene segments encoding variable parts of the T cell receptor for the antigen (TCR). Quite paradoxically, neuroendocrine self-peptide presentation in the thymus also generates regulatory T (tTreg) cells that inhibit, in the periphery, those self-reactive T cells having escaped thymic negative selection. Several arguments indicate that the origin of autoimmunity directed against neuroendocrine glands results from a primary defect in the intrathymic programming of self-tolerance to neuroendocrine principles. This defect may be genetic or acquired, for example during a viral infection. This novel knowledge of normal and pathologic functions of the thymus constitutes a solid scientific basis for the development of a novel type negative self-vaccination against type 1 diabetes. (Supported by NFSR of Belgium, Wallonia and FP6 Eurothymaide.) [less ▲]

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See detailSpanish Saints in the Spanish Netherlands
Delfosse, Annick ULg

Conference (2014, March 27)

In the seventeenth century, the Roman proclamations of beatification or canonization generated a large number of festivities and spectacular events in many parts of the Monarchy of Spain. Yet, in the ... [more ▼]

In the seventeenth century, the Roman proclamations of beatification or canonization generated a large number of festivities and spectacular events in many parts of the Monarchy of Spain. Yet, in the Netherlands, they received a fainter echo and left a limited number of sufficiently documented testimonies. Two cases, however, are exceptions: the canonization of Ignatius of Loyola and Francis Xavier triumphantly celebrated by the Belgian Jesuits in 1622, and the beatification of Francisco Borgia in 1624, i.e., the elevation to the Catholic pantheon of three Spanish saints rejoiced by an order marked by its hispanophile nature, in provinces recently returned to the Spanish Crown. I will seek to define the Hispanic features of these events and I will particularly stress the very noticeable way how the Spanish communities, present in the Low Countries, committed themselves in these festivities. [less ▲]

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See detailLa forêt luxembourgeoise en chiffres - Résultats de l'Inventaire Forestier National au Grand-Duché de Luxembourg 2009 - 2011
Rondeux, Jacques ULg; Alderweireld, Matthieu ULg; Saidi, Mohammed ULg et al

Book published by Administration de la nature et des forêts du Grand-Duché de Luxembourg - Service des forêts (2014)

Results from the second Luxembourg's national forest inventory (2009-2011) and comparison with the first inventory (1998-2000).

Detailed reference viewed: 33 (12 ULg)
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See detailComment améliorer les taux de matières utiles dans le lait ? Solutions actuelles et perspectives ...
Beckers, Yves ULg

Conference given outside the academic context (2014)

Detailed reference viewed: 19 (2 ULg)
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See detailValuation and price expectation mismatch in SME business transfer
Lambert, Marie ULg

Conference (2014, March 26)

Detailed reference viewed: 22 (7 ULg)