Last 7 days
Bookmark and Share    
Full Text
See detailConvention Région wallonne et HGE-ULg Caractérisation complémentaire des masses d’eau dont le bon état dépend d’interactions entre les eaux de surface et les eaux souterraines - Délivrable D1.8 Rapport final
Brouyère, Serge ULg; Briers, Pierre ULg; Descy, Jean-Pierre et al

Report (2017)

Mechanisms of interactions between groundwater bodies and rivers whose status and anthropogenic use can be detrimental from a quantitative and qualitative point of view to one or the other of these two ... [more ▼]

Mechanisms of interactions between groundwater bodies and rivers whose status and anthropogenic use can be detrimental from a quantitative and qualitative point of view to one or the other of these two compartments of the water cycle. In addition, contamination of groundwater by nitrate remains relevant. Based on these observations, a study financed by the Public Service of Wallonia was carried out over a period of 39 months to investigate (1) the direction, importance and dynamics of water exchange between groundwater and rivers at the scale of a river section; (2) the impact of these interactions on river baseflows and the river ecological status as a function of groundwater withdrawal and recharge at the catchment scale; (3) mechanisms and timing of transfer and abatement of pollutants (nitrate) between groundwater and surface waters at the watershed scale. The consequences of these mechanisms on the medium- and long-term evolution of groundwater and surface water quality were to be determined. To achieve this, the project relied on the implementation of a series of field investigations essentially focused on the interfaces between surface water and groundwater compartments (soil and unsaturated zone and water-table interface), while acquiring additional information on groundwater. The investigations carried out in the watersheds of the upstream Hoyoux and Triffoy watershed in the Condroz region aimed to provide 6 specific responses to water quantity and quality issued associated with groundwater – surface water interactions in the selected basins and generic responses in the form of new knowledge concerning the mechanisms of recharge and groundwater - river exchanges, concerning the evolution of nitrate concentrations in watersheds, data and measurements for the parameterization of models, and water resources management tools in the form of quantitative and qualitative indicators for groundwater - surface water interactions. [less ▲]

Detailed reference viewed: 58 (10 ULg)
Full Text
Peer Reviewed
See detailThe design and study of new Li-ion full cells of LiCo2/3Ni1/6Mn1/6O2 positive electrode paired with MnSn2 and Li4Ti5O12 negative electrodes
Mahmoud, Abdelfattah ULg; Saadoune, Ismael; Lippens, Pierre-Emmanuel et al

in Solid State Ionics (2017), 300

We report evidence for the electrochemical performances of two Li-ion full cells, built up by the combination of LiCo2/3Ni1/6Mn1/6O2 cathode material with MnSn2 intermetallic and Li4Ti5O12 spinel as the ... [more ▼]

We report evidence for the electrochemical performances of two Li-ion full cells, built up by the combination of LiCo2/3Ni1/6Mn1/6O2 cathode material with MnSn2 intermetallic and Li4Ti5O12 spinel as the anode materials, respectively. MnSn2 and Li4Ti5O12 electrode materials illustrate different working voltage versus the redox couple Li+/Li0 and different reactionmechanisms during lithiuminsertion/deinsertion cycles. The structure,morphological characteristics and the electrochemical properties of the studied materialswere investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM) and electrochemical techniques. The two full-cell configurations showed different electrochemical behaviors. The MnSn2//LiCo2/3Ni1/6Mn1/6O2 configuration exhibits high working voltage (~3.5 V) and specific capacity (~200 mAh/gcathode) but suffers from high irreversible capacity loss during the first cycles and capacity fading during cycling. The Li4Ti5O12//LiCo2/3Ni1/6Mn1/6O2 cell demonstrated excellent cycling properties at different C-rates with 100% capacity retention after 150 cycles at 1 C. Although the working voltage (~2.2 V) and the specific capacity (~140 mAh/gcathode) are lower than those of the MnSn2//LiCo2/3Ni1/6Mn1/6O2 configuration, the other measured electrochemical properties suggest that the Li4Ti5O12//LiCo2/3Ni1/6Mn1/6O2 full cell is a potential candidate for battery application due to its excellent cycling performance and improved safety. [less ▲]

Detailed reference viewed: 14 (2 ULg)
Full Text
Peer Reviewed
See detailPESTO SAUCE TYPE PRODUCTS: INFLUENCE OF BEESWAX AND STORAGE CONDITIONS ON RHEOLOGY AND COLLOIDAL STABILITY
Bouacida, Saoussen; Muresan, Vlad; Essaidi, Ismahen et al

in Journal of Microbiology, Biotechnology and Food Sciences (2017), 6(3), 911-920

One of the major problems for pesto sauce type products is the tendency of oil to cream, causing their alteration and decreasing consumer’s acceptability. In this study, colloidal and oxidative stability ... [more ▼]

One of the major problems for pesto sauce type products is the tendency of oil to cream, causing their alteration and decreasing consumer’s acceptability. In this study, colloidal and oxidative stability of pesto samples with (0.5-1.2%) of beeswax was evaluated during storage at 4, 20 and 40°C. The rheological behavior and color analysis was evaluated at the same temperatures. Sensory evaluation by using a hedonic test was also perfomed. Increasing the samples beeswax content increased the pesto colloidal stability. The samples with 0.8-1.2% have the highest stability and overall performed well on sensory analysis. The peroxide values of samples increased significantly (p<0.05) with storage time and temperature, as well as the p-anisidine values. During the storage at 40°C, peroxide values of samples without wax and with 1,2% wax increased from 11.75 to 33.81 and 32.72 meq O2/kg, respectively. In the same condition, p-Anisidine values increased from 4.51 to 10.71 and 9.94, respectively. For these same samples stored 793 h, peroxide values increased from 13.33 to 33.81 and to 32.72 meq O2/kg, when the temperature increased from 4 to 40°C. The same observation was made for p-anisidine values, which increased from 8.40 to 10.71 and 9.94. As expected, the pesto samples showed the best oxidative stability at low temperature. It was shown that beeswax content, temperature and time of storage are important parameters for controlling pesto rheology, colloidal and oxidative stability. In fact, the pseudo plasticity of samples increases with increasing beeswax added and with decreasing the temperature. The colloidal and oxidative stability of samples decreased as the storage time and temperature increased. [less ▲]

Detailed reference viewed: 14 (1 ULg)
Full Text
Peer Reviewed
See detailDynamics and emissions of N2O in groundwater: A review
Jurado Elices, Anna ULg; Borges, Alberto ULg; Brouyère, Serge ULg

in Science of the Total Environment (2017), 584-585C

This work reviews the concentrations, the dynamics and the emissions of nitrous oxide (N2O) in groundwater. N2O is an important greenhouse gas (GHG) and the primary stratospheric ozone depleting substance ... [more ▼]

This work reviews the concentrations, the dynamics and the emissions of nitrous oxide (N2O) in groundwater. N2O is an important greenhouse gas (GHG) and the primary stratospheric ozone depleting substance. The major anthropogenic source that contributes to N2O generation in aquifers is agriculture because the use of fertilizers has led to the widespread groundwater contamination by inorganic nitrogen (N) (mainly nitrate, NO3−). Once in the aquifer, this inorganic N is transported and affected by several geochemical processes that produce and consume N2O. An inventory of dissolved N2O concentrations is presented and the highest dissolved concentration is about 18.000 times higher than air-equilibrated water (up to 4004 μg N L-1). The accumulation of N2O in groundwater is mainly due to denitrification and to lesser extent to nitrification. Their occurrence depend on the geochemical (e.g., NO3−, dissolved oxygen, ammonium and dissolved organic carbon) as well as hydrogeological parameters (e.g., groundwater table fluctuations and aquifer permeability). The coupled understanding of both parameters is necessary to gain insight on the dynamics and the emissions of N2O in groundwater. Overall, groundwater indirect N2O emissions seem to be a minor component of N2O emissions to the atmosphere. Further research might be devoted to evaluate the groundwater contribution to the indirect emissions of N2O because this will help to better constraint the N2O global budget and, consequently, the N budget. [less ▲]

Detailed reference viewed: 49 (1 ULg)
Full Text
See detailEvaluations à large échelle : prendre la juste mesure des effets de contexte
Lafontaine, Dominique ULg

in Detroz, Pascal; Crahay, Marcel; Fagnant, Annick (Eds.) L'évaluation à la lumière des contextes et des disciplines (2017)

Detailed reference viewed: 21 (4 ULg)
Peer Reviewed
See detailPratiques de GRH en RDC ou comment gérer les contradictions dans un contexte d’instabilité
Sem Mbimbi, pascal; M'Bayo Musewa Laki, Maurice; Cornet, Annie ULg

in Dupriez, Pierre; Vanderlinden, Blandine (Eds.) Au cœur de la dimension culturelle du Management (2017)

Detailed reference viewed: 169 (13 ULg)
Peer Reviewed
See detailProtecting Assets Under Non-Parametric Market Conditions
Choffray, Jean-Marie ULg; Pahud de Mortanges, Charles ULg

in Longin, François (Ed.) Extreme Events in Finance: A Handbook of Extreme Value Theory and its Applications (2017)

Under non-parametric market conditions, investors usually become more concerned about the return of their money than about the return on their money. Protecting assets becomes the surest if not the only ... [more ▼]

Under non-parametric market conditions, investors usually become more concerned about the return of their money than about the return on their money. Protecting assets becomes the surest if not the only path to survival and growth. High frequency trading systems, over leveraged shadow entities, flash crashes, and stealth central bank actions, to name a few, contribute to create a “Rumsfeldian” type of world in which decision makers have to cope not only with “Known knowns” – things they know that they know – but also with “Unknown unknowns” – things they don’t know that they don’t know! The goal of this chapter is to explore such a conceptual model of the “Unknown” and to derive from it a concise and coherent set of battle-tested heuristics aimed at designing effective investment strategies to protect assets. [less ▲]

Detailed reference viewed: 671 (59 ULg)
Full Text
See detailUnsteady lifting line theory using the Wagner function
Boutet, Johan ULg; Dimitriadis, Grigorios ULg

in Proceedings of the 55th AIAA Aerospace Sciences Meeting (2017, January)

A method is presented to model the incompressible, attached, unsteady lift and moment acting on a thin three-dimensional wing in the time domain. The model is based on the combination of Wagner theory and ... [more ▼]

A method is presented to model the incompressible, attached, unsteady lift and moment acting on a thin three-dimensional wing in the time domain. The model is based on the combination of Wagner theory and lifting line theory trough the unsteady Kutta-Joukowsky theorem. The result is a set of closed form linear ordinary di erential equations that can be solved analytically or using a Runge-Kutta-Fehlberg algorithm. The method is validated against numerical predictions from an unsteady Vortex Lattice method for rectangular and tapered wings undergoing step or oscillatory changes in plunge or pitch. As the aerodynamic loads are written in state space form in the proposed method, they can be easily included in aeroelastic and flight dynamic calculations. [less ▲]

Detailed reference viewed: 15 (1 ULg)
Full Text
See detailCompte rendu: AXEMAN's JAZZ et DEAD MAN'S BLUES ( Ray Celestin)
Sacré, Robert ULg

in ABS Magazine (2017), (53),

Detailed reference viewed: 12 (0 ULg)
Full Text
See detailCompte-rendu de l'ouvrage de Robert Ford et Bob McGrath : ZYDECO DISCOGRAPHY 1949-2010
Sacré, Robert ULg

in ABS Magazine (2017), (53),

Detailed reference viewed: 18 (0 ULg)
Full Text
Peer Reviewed
See detailReversible TAD chemistry as a convenient tool for the design of (re)processable PCL-based shape-memory materials
Defize, Thomas ULg; Riva, Raphaël ULg; Thomassin, Jean-Michel ULg et al

in Macromolecular Rapid Communications (2017), 38(1), 1600517

A chemically cross-linked but remarkably (re)processable shape-memory polymer (SMP) is designed by cross-linking poly(ε -caprolactone) (PCL) stars via the efficient triazolinedione click chemistry, based ... [more ▼]

A chemically cross-linked but remarkably (re)processable shape-memory polymer (SMP) is designed by cross-linking poly(ε -caprolactone) (PCL) stars via the efficient triazolinedione click chemistry, based on the very fast and reversible Alder– ene reaction of 1,2,4-triazoline-3,5-dione (TAD) with indole compounds. Typically, a six-arm star-shaped PCL function- alized by indole moieties at the chain ends is melt-blended with a bisfunctional TAD, directly resulting in a cross-linked PCL-based SMP without the need of post-curing treatment. As demonstrated by the stress relaxation measurement, the labile character of the TAD–indole adducts under stress allows for the solid-state plasticity reprocessing of the permanent shape at will by compression molding of the raw cross-linked material, while keeping excellent shape-memory properties. [less ▲]

Detailed reference viewed: 43 (23 ULg)
Full Text
See detailMARTIAN ULTRAVIOLET AURORA: RESULTS OF MODEL SIMULATIONS
Gérard, Jean-Claude ULg; Soret, Lauriane ULg; Shematovich, V.I. et al

Conference (2017, January)

We present recent modeling results based on observations performed with the UV spectrographs on board the Mars Express and MAVEN missions.Two types of aurora are discussed: the localized and transient ... [more ▼]

We present recent modeling results based on observations performed with the UV spectrographs on board the Mars Express and MAVEN missions.Two types of aurora are discussed: the localized and transient discrete aurora and the more stable diffuse aurora observed during periods of active solar periods. [less ▲]

Detailed reference viewed: 17 (0 ULg)
Full Text
Peer Reviewed
See detailQuartz-enhanced photo-acoustic spectroscopy for breath analyses
Petersen, J; Lamard, L; Feng, P et al

in Proceedings SPIE (2017, January), 10055

Detailed reference viewed: 10 (4 ULg)
See detailThe road from the adenoma valley through the forest of genetic testing in pituitary adenoma
Beckers, Albert ULg

Scientific conference (2017, January)

Detailed reference viewed: 16 (1 ULg)
Full Text
See detailAs teorias semióticas diante da fotografia
Dondero, Maria Giulia ULg

in Rodrigues, Angelica; Rocha, Nildicéia (Eds.) Proceedings VI SELIN – The Unesp Linguistics Studies Seminar (2017, January)

Dans ce texte, je me propose de revenir sur les travaux en sémiotique qui ont marqué les études du champ interdisciplinaire de la photographie et de les poursuivre; l’objectif principal est de fournir ... [more ▼]

Dans ce texte, je me propose de revenir sur les travaux en sémiotique qui ont marqué les études du champ interdisciplinaire de la photographie et de les poursuivre; l’objectif principal est de fournir quelques pistes pour étudier, d’un point de vue sémiotique, l’image photographique en tant qu’objet pris dans des pratiques d’usage et d’interprétation diversifiées au sein des statuts sociaux de l’art, de la science, de la religion. [less ▲]

Detailed reference viewed: 20 (1 ULg)
Full Text
See detailDu bon usage des faits en régime de " post­-vérité"
Thoreau, François ULg; Zimmer, Alexis

Article for general public (2017)

Detailed reference viewed: 26 (0 ULg)
Full Text
Peer Reviewed
See detailPost-embryonic development of sheepshead minnow Cyprinodon variegatus: a staging tool based on externally visible anatomical traits
Schnitzler, Joseph ULg; Dussenne, Mélanie ULg; Frederich, Bruno ULg et al

in Ichthyological Research (2017), 64

The sheepshead minnow Cyprinodon variegatus has become a favoured model for laboratory studies because of their small size, rapid development, and tolerance of laboratory conditions. Here, we analyse ... [more ▼]

The sheepshead minnow Cyprinodon variegatus has become a favoured model for laboratory studies because of their small size, rapid development, and tolerance of laboratory conditions. Here, we analyse sheepshead minnow post-embryonic development with the goal of providing a generally useful method for staging fish after embryogenesis. Groups of three females and two males were placed in breeding chambers designed for this experiment. More than 100 eggs were collected and maintained in seawater. Embryos were selected under a dissection microscope and placed in incubation dishes (50 per dish) at 26 °C. On day six, embryos hatched and larvae were transferred to 1 L beakers. To define a simplified normalization table for sheepshead minnow development, we measured each fish for its standard length and examined the fish for four externally evident traits: pigmentation pattern, caudal fin morphology, anal fin morphology, and dorsal fin morphology. The four traits were chosen, because they are easily visualized with standard laboratory equipment such as the stereomicroscope and camera. We have provided criteria for staging sheepshead minnows in studies of post-embryonic development. Our data suggest that dorsal and anal fin morphology may serve as a useful phenotype for defining metamorphic climax stages throughout post-embryonic development in C. variegatus. The staging systems we propose should facilitate detailed anatomical and developmental analyses in relation to ecotoxicological studies on potential disruption of the thyroid axis by xenobiotics and endocrine-disrupting compounds. [less ▲]

Detailed reference viewed: 37 (12 ULg)