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See detail"Madame Bovary c'est moi"
Cormann, Grégory ULg

Conference (2016, October 29)

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See detailDas Ende der Phantomschmerzen. Die Bundesrepublik und "Eupen-Malmedy"
Brüll, Christoph ULg

Scientific conference (2016, October 28)

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See detailBounding surface plasticity model for natural clays
Ahayan, Sanae ULg; Yin, Zhen-Yu; Kotronis, Panagiotis et al

Conference (2016, October 26)

Natural soft clay exhibits a considerable degree of anisotropy as a result of its past sedimentation and consolidation history. It also tends to have significant inter-particle bonding, which affects its ... [more ▼]

Natural soft clay exhibits a considerable degree of anisotropy as a result of its past sedimentation and consolidation history. It also tends to have significant inter-particle bonding, which affects its mechanical behavior. The natural structure of in-situ soils makes their behavior different from that of a reconstituted material. In fact, most clays lose a proportion of their strength when remoulded. Various authors proposed anisotropic elastoplastic soil models allowing the yield surface to rotate with the stress history. These models have a “rotational hardening law" which relates the change of the inclination of the yield surface to the current soil state and to the increments of the plastic volumetric and/or shear strain, [Sekiguchi and Otha (1977)], [Hashiguchi and Chen (1998)], [Wheeller et al (2003)]… Other authors combine the plastic anisotropy with destructuration effects observed in soft sensitive soils by assuming that the size and /or the position of the center of the yield surface depends on the amount of the structural soil degradation. These models use an additional isotropic hardening law that relates the size and/or the position of the yield surface of the intact sample to that of the reconstituted one [Nova et al (2003)]. The previous models provide little or no flexibility when it comes to describe the change of the plastic modulus with the loading direction as they are unable to produce a smooth degradation of the stiffness, being single yield surface models. A way to improve this behavior is to introduce the “bounding surface plasticity” theory, initially developed by Dafalias [Dafalias and Herrmann 1986]. Unlike a single yield surface model, the bounding surface theory allows a smooth transition of stresses within and on the bounding surface. The mean feature of this concept is that the actual stress is mapped to the imaginary stress on the bounding surface. The distance between the real and imaginary stress, which is called the “ function distance ”, is used to specify the plastic modulus. This work presents a bounding surface plasticity model for natural and structured clays based on the critical state theory. A novel rotational hardening rule for clays is presented, and a hardening function distance is introduced to describe the evolution of the bounding surface. Validation of the model is provided by drained and undrained tests of Scottish and Finnish intact and reconstituted clays [Kastunnen 2008]. Finally, finite element simulations of a foundation considering the formulated constitutive law are presented. [less ▲]

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See detailLe droit international : un fleuron de la Belgique
Genin, Vincent ULg

Conference given outside the academic context (2016)

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See detailSU(3) Clebsch-Gordan coefficients at large $N_c$
Stancu, Floarea ULg

in Nuclear Physics A (2016), 945

It is argued that several papers where SU(3) Clebsch-Gordan coefficients were calculated in order to describe properties of hadronic systems are, up to a phase convention, particular cases of analytic ... [more ▼]

It is argued that several papers where SU(3) Clebsch-Gordan coefficients were calculated in order to describe properties of hadronic systems are, up to a phase convention, particular cases of analytic formulae derived by Hecht in 1965 in the context of nuclear physics. This is valid for irreducible representations with multiplicity one in the corresponding Clebsch-Gordan series. For multiplicity two, Hecht has proposed an alternative which can provide correct $1/N_c$ sub-leading orders in large $N_c$ studies. [less ▲]

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See detailMathias Enard, traducteur nomade
Bada, Valérie ULg

Speech/Talk (2016)

A travers 4 traductions de Mathias Enard (deux poèmes issus de la tradiction littéraire obscène persane et arabe du 19e s, ainsi qu'un récit autobiographique traduit de l'arabe du Liban et un recueil de ... [more ▼]

A travers 4 traductions de Mathias Enard (deux poèmes issus de la tradiction littéraire obscène persane et arabe du 19e s, ainsi qu'un récit autobiographique traduit de l'arabe du Liban et un recueil de nouvelles traduites du castillan), le rapport à la langue de traduction et à sa langue de création littéraire est évoqué ainsi que l'intervention créative dans le texte traduit. Est évoquée également la visibilité du traducteur à travers la préface et la postface de ses traductions. [less ▲]

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See detailPsychiatrie et liberté : approche phénoménologique
Englebert, Jérôme ULg; Cormann, Grégory ULg

Conference (2016, October 22)

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See detailLe clergé à Eupen-Malmedy durant l'entre-deux-guerres
Brüll, Christoph ULg

Conference given outside the academic context (2016)

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See detailThe Middle Ages: A New Age for the Reception of the Gods of Egypt
Veymiers, Richard ULg

Conference (2016, October 20)

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See detailPrison : face à l'enfermement des corps
Englebert, Jérôme ULg

Conference given outside the academic context (2016)

Detailed reference viewed: 19 (2 ULg)
See detailXérogels de carbone comme matériaux modèles pour l'étude du comportement électrochimique en tant qu'anodes de batteries Li-ion
Piedboeuf, Marie-Laure ULg

Doctoral thesis (2016)

The main goal of this thesis aims at shedding some light on how the textural and surface chemistry properties of porous carbons influence their electrochemical behavior when used as anodes for Li-ion ... [more ▼]

The main goal of this thesis aims at shedding some light on how the textural and surface chemistry properties of porous carbons influence their electrochemical behavior when used as anodes for Li-ion batteries. In this respect, carbon xerogels (XC) have been used as model materials, since their tunable pore texture and surface chemistry have made it possible to perform a systematic study, where each variable could be modified independently. The first target consisted in obtaining a series of carbon xerogels with controlled meso- or macropore textures. These materials are made of interconnected nearly spherical microporous nodules, delimiting meso- or macroporous voids. Several series of carbon xerogels with controlled pore textures have been prepared. As a result, materials with a wide range of meso- or macropore sizes have been obtained and the influence of the aqueous formaldehyde precursor solution on the final textural characteristics could be highlighted. Additional post-synthesis treatments have been performed in order to tune the microporosity as well as the surface chemistry of selected materials. The second aim was to control and set several variables other than the pore texture and the surface chemistry of XC, that could influence their behavior as active materials for Li-ion batteries, such as the particle sizes or the electrode characteristics. In this respect, an in-depth study of the ball-milling process of carbon xerogels has allowed to determine the conditions leading to materials with a well-defined particle size distribution centered on 10 µm. The specific surface area, as well as the meso- or macroporosity remain identical from the monolithic form to the final powder. This work has also shown the possibility of using mercury intrusion porosimetry as a tool to assess the mean particle sizes of a XC powder. Several methods for the coating of active materials on current collectors (bar-coating and spray) have been investigated for different ink formulations (organic- or water-based). This study has shown that XC-binder composites resulting from aqueous-based inks preserve the porosity of the starting materials, whereas the microporosity is strongly reduced in the case of the organic pathway. As a result, the method of spraying a water-based ink, with xanthan gum as a binder, seems to be the most appropriate in terms of precision, ease of processing and safety in this case. The third goal consisted in performing detailed electrochemical characterizations of the electrodes produced with carbon xerogels displaying various defined pore textures and surface chemistries. In the case of electrodes obtained upon using an organic ink, a linear relationship is observed between the relative irreversible losses and i) the external surface area of the nodules as well as ii) the specific surface area of the XC-binder composites. In the case of the aqueous electrode processing method and upon using carbon xerogels with tuned microporosity, a linear relationship could be established between the total specific surface area of the starting materials (including micropores) and the irreversible as well as reversible capacities at the first charge-discharge cycle, if the maximum potential is set at 3 V vs. Li+/Li. Finally, after modulation, the surface chemistry has shown to have a significant effect on the accessibility of the surface by the electrolyte as well as on the SEI formation at the first charge-discharge cycle. [less ▲]

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See detailQUALITY EVALUATION OF AMOXICILLIN AND COMBINATION OF AMOXICILLIN – POTASSIUM CLAVULANATE AS PART OF INVESTIGATION OF THE OFFICIAL AND PERIPHERAL DRUG MARKET IN KINSHASA, LUMBUBASHI AND KOLWEZI - DRC.
Kalenda Tshilombo, Nicodème ULg; Marini Djang'Eing'A, Roland ULg; Hubert, Philippe ULg et al

Conference (2016, October 18)

Drug substandard and counterfeiting is a sad and worrisome reality, especially in developing countries where quality control is not effective and sometimes not existing at all despite political will of ... [more ▼]

Drug substandard and counterfeiting is a sad and worrisome reality, especially in developing countries where quality control is not effective and sometimes not existing at all despite political will of governments.In this context, we have focused our study towards amoxicillin alone and/or combined with potassium clavulanate since it is one the very used medicines in pediatric medications.Two analytical methods were developed based on the USP monograph. Prior to their application in routine, we evaluated the suitability of these methods through validation applying the accuracy profile of total error. The latter were able to allow monitoring the quality of the two active ingredients here above in the 50 samples from Congolese market. They were collected in Kinshasa, Lumbubashi and Kolwezi at official and non official medicines distributors, in peripheral area. The dramatic results obtained confirm that substandard and counterfeit medicines remain a crucial problem on public health in low-income countries [less ▲]

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See detailAnorexie et régulation émotionnelle
Englebert, Jérôme ULg

Conference (2016, October 08)

Detailed reference viewed: 33 (4 ULg)
Peer Reviewed
See detailShaping (im)mobility: borders, camps, and non-state actors
Da Silva, Amanda Carolina ULg

Conference (2016, October 07)

Detailed reference viewed: 16 (3 ULg)
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See detailIsolement et caractérisation de mutants affectés dans le transport d'électrons photosynthétique en anoxie chez la microalgue verte Chlamydomonas reinhardtii. Photoproduction d'hydrogène et Voie de biosynthèse de la phylloquinone.
Emonds-Alt, Barbara ULg

Doctoral thesis (2016)

La microalgue verte Chlamydomonas reinhardtii, qui a contribué de façon remarquable à la compréhension de nombreux mécanismes biologiques tels que la photosynthèse, intéresse aujourd’hui plus ... [more ▼]

La microalgue verte Chlamydomonas reinhardtii, qui a contribué de façon remarquable à la compréhension de nombreux mécanismes biologiques tels que la photosynthèse, intéresse aujourd’hui plus particulièrement le secteur des énergies renouvelables pour sa capacité à produire de l’hydrogène moléculaire (H2) à la lumière. Cette photoproduction d’H2 est liée à la présence en anoxie d’hydrogénases qui sont connectées via la ferrédoxine à la chaîne de transport d’électrons photosynthétique. On distingue deux voies de transfert d’électrons: la première dépendant de la photolyse de l’eau par le PSII (voie PSII-dépendante), la seconde de l’action d’une NAD(P)H déshydrogénase de type II (NDA2, voie PSII-indépendante). En raison de la sensibilité des hydrogénases à l’oxygène, cette production n’est que transitoire. Bien que ce processus puisse potentiellement réduire notre dépendance aux énergies fossiles, il est à l’heure actuelle économiquement inexploitable compte tenu de sa faible productivité. L’amélioration génétique des microalgues pourrait partiellement remédier à ce problème mais cette stratégie nécessite toutefois de posséder une connaissance fondamentale de toutes les voies métaboliques impliquées dans ce processus spécifique de l’anoxie. Afin d’identifier de nouvelles enzymes clés contrôlant la photoproduction d’H2 et de manière plus générale le métabolisme anaérobique, chez l’algue modèle Chlamydomonas reinhardtii, nous avons cherché dans un premier temps à comprendre la fonction de la protéine NDA3, une NAD(P)H déshydrogénase de type II chloroplastique. A l’instar de NDA2, celle-ci pourrait potentiellement participer à la réduction non-photochimique du pool de plastoquinones. Dans un deuxième temps, nous avons contribué au développement d’une nouvelle technique de criblage «haut débit» basée sur l’enregistrement de la cinétique d’induction de fluorescence des algues lors d’une transition de l’obscurité à la lumière en anoxie. Grâce à l’efficacité et à la rapidité de cette méthode nous avons pu identifier au sein d’une large collection de mutants insertionnels (~ 23 000) quatre mutants déficients pour le facteur d’assemblage HYDG (essentiel à la maturation des hydrogénases) et quatre autres mutants déficients pour la voie de biosynthèse de la phylloquinone. La caractérisation subséquente de ces mutants par des méthodes génétiques, moléculaires, biochimiques et biophysiques, nous a ainsi permis de comprendre in fine l’impact négatif de la perte du facteur HYDG ou de la phylloquinone sur le transfert d’électrons photosynthétique en anoxie. [less ▲]

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See detailTowards a large scale aqueous sol-gel synthesis of doped TiO2: Study of various metallic dopings for the photocatalytic degradation of p-nitrophenol
Mahy, Julien ULg; Lambert, Stéphanie ULg; Léonard, Géraldine ULg et al

in Journal of Photochemistry and Photobiology A : Chemistry (2016), 329

In this paper, an easy aqueous sol-gel synthesis developed previously by Mahy et al. [J. Sol-Gel Sci. Technol. (2016)] is adapted to produce highly active TiO2 catalysts doped with Fe3+, Ag+, Cu2+, Zn2 ... [more ▼]

In this paper, an easy aqueous sol-gel synthesis developed previously by Mahy et al. [J. Sol-Gel Sci. Technol. (2016)] is adapted to produce highly active TiO2 catalysts doped with Fe3+, Ag+, Cu2+, Zn2+, Cr3+, Al3+, Mn2+, and Co2+ ions and Pt metallic nanoparticles. Samples are characterized by inductively coupled plasma–atomic emission spectroscopy (ICP-AES), X-ray diffraction (XRD), Mössbauer spectroscopy, transmission electron microscopy (TEM), nitrogen adsorption–desorption measurements and diffuse reflectance spectroscopy measurements. Results show that the samples are composed of anatase-brookite TiO2 nanoparticles with a spherical shape and mean diameter of around 5-8 nm and a surface area of between about 150 - 250 m2 g-1. In each doped sample, the dopant is present in the form added during the synthesis, given that the sample has not undergone any particular treatment. Photoactivity tests show improvement in catalyst activity for Fe3+, Ag+, Cu2+, Zn2+, and Al3+ ion and Pt metallic nanoparticle dopants, while a decrease of activity is obtained for Cr3+, Mn2+ and Co2+ ion dopants. For some dopants, the activity of TiO2 doped with metallic ions and synthesized from the aqueous sol-gel process is equal or superior to the activity of the commercial photocatalyst Degussa P25. Some mechanisms are proposed to explain these modifications of activity with doping. Furthermore, cost comparison at laboratory scale showed that Zn and Cu nitrate salt dopings are clearly less expensive for a halogen light (UV/visible) or low energy light enhanced catalyst and may be considered for industrial applications. Using this method, a large scale Zn-doped TiO2 photocatalyst is synthesized with properties homologous to the lab-scale product. Results show that the aqueous sol-gel synthesis developed previously can be easily adapted for doping in order to produce an up-scalable synthesis. [less ▲]

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