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See detailHydrothermal self-assembly of sodium manganese iron phosphate particles: Growth mechanism and electrochemical performance in lithium-ion battery
Karegeya, claude; Mahmoud, Abdelfattah ULiege; Vertruyen, Bénédicte ULiege et al

in Solid State Ionics (2017), 312

Na2Mn1.5Fe1.5(PO4)3 (NMFP) dandelion sphere-like particles were successfully synthesized via a hydrothermal route without addition of any templates or surfactants (laboratory and pilot scales). The ... [more ▼]

Na2Mn1.5Fe1.5(PO4)3 (NMFP) dandelion sphere-like particles were successfully synthesized via a hydrothermal route without addition of any templates or surfactants (laboratory and pilot scales). The hydrothermal reactor (pilot scale) is equipped with stirrer for continuous agitation of reagents during the reaction. The obtained materials were characterized by X-ray diffraction, Mössbauer spectroscopy and Scanning electron microscopy. Results show that Na2Mn1.5Fe1.5(PO4)3 samples obtained from the reaction performed at laboratory scale have hierarchical dandelion sphere-like morphology and the dandelions consist of micro-/nano-rods. On the other hand, we obtained the self-assembly nano-rods morphology for the particles prepared using hydrothermal reactor. On the basis of the experimental results, a growth mechanism of Na2Mn1.5Fe1.5(PO4)3 self-assembly and dandelion sphere-like particles was proposed. Temperature and time of hydrothermal reaction are found to be crucial parameters in controlling the growth of Na2Mn1.5Fe1.5(PO4)3 particles. In addition, investigation of the effect of continuous stirring during the hydrothermal reaction shows that the reaction time can be optimized to obtain Na2Mn1.5Fe1.5(PO4)3 with small particles size. The influence of stirring on the NMFP morphology has been clearly evidenced. Indeed, the stirring leads to homogeneous particles. Cycling studies have shown that the synthesized Na2Mn1.5Fe1.5(PO4)3 dandelions materials exhibit specific discharge capacities of about 62 and 57 mAh g−1 equivalent to about 1.2 and 1.05 lithium ions de-intercalated at C/15 and C/10 current density respectively. [less ▲]

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See detailVigne guida Confedilizia alla giornata di Varsavia
Gagliani Caputo, Giovanni; Grandjean, Geoffrey ULiege

Article for general public (2017)

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See detailPoints de vue de dominants sur les prostitutions en Fédération Wallonie – Bruxelles
Govers, Patrick; Absil, Gaëtan ULiege

Conference (2017, October 20)

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See detailUpscaling winter wheat above-ground biomass measurements using multispectral imagery and 3D data from unmanned aerial vehicle
Michez, Adrien ULiege; Bauwens, Sébastien ULiege; Heinesch, Bernard ULiege et al

Poster (2017, October 20)

Field measurements in the ICOS program are spatially limited whereas the monitored gas fluxes may have a large footprint. Aerial remote sensing has the advantage to monitor large areas. The main goal of ... [more ▼]

Field measurements in the ICOS program are spatially limited whereas the monitored gas fluxes may have a large footprint. Aerial remote sensing has the advantage to monitor large areas. The main goal of our research was to test the potential of unmanned aerial vehicles (UAV) to upscale parameters monitored through the ICOS program. In this study, we specifically focus on above-ground biomass (AGB) monitoring in a winter wheat crop. We used a octocopter drone (X frame type) to acquire a time series over the crop growing season (8 flights from the 14th of February 2017 to the 7th of July 2017) of multispectral imagery covering the ICOS candidate station of Lonzée (Wallonia, Belgium) and the surrounding field crop areas (ca. 0.25 km² per flight). The multispectral camera provides spectral information on the green (550 +/- 50 nm), red (660 +/- 50 nm), near infrared (735 +/- 50 nm) and red-edge (790 +/- 10 nm) wavelengths bands. The UAV also brought an off-the-shelf high resolution (20 Mpx) RGB camera to derive accurate 3D data. We performed a photogrammetric 3D reconstruction of the acquired imagery for every flight survey. The images provided by the RGB sensor (Sony RX100) were used to produce a high spatial resolution Digital Surface Model (0.05 m) and the images acquired by the multispectral sensor were used to derive reflectance maps (0.1 m) in the four wavelengths bands. The four reflectance layers were combined to produce two straight-forward vegetation indices (Normalized Difference Vegetation Index and Green NDVI). The photogrammetric DSM’s were combined to a LiDAR Digital Terrain Model (public database, survey in winter 2013) to produce Crop Height Models (CHM) of the study area. We used multiple linear regressions modelling in order to predict the AGB of the field crop monitored by the ICOS station of Lonzée with UAV imagery. AGB=a+b*GNDVI+c*NDVI+d *CHM The field crop data were provided by the ICOS program and by field research conducted in experimental field crops close to the flux tower. The field sampling consisted in destructive samples of the crop which were weighted after drying. For each field sample, an associated area was computed based on the outdistance sowing and the number of sampled crops in order to compute an AGB per area unit (t / Ha). Each AGB field estimation was associated to the closest flight date to build a multi date model presenting good performances (r² = 0.85, RMSE = 2.3 t/Ha). We used the same modelling approach to adjust a single date model to derive a predicted AGB map for the 7th of July. The performance of the single date model is lower but still highlights the biomass variation within the crop (r² = 0.71, RMSE = 1.9 t/Ha). The predicted AGB map displays a high spatial heterogeneity with some spatial patterns. Locally low AGB values are found along two old pedestrian whereas higher AGB values can be associated to areas which were sprayed twice (in-between two tractor tracks). Our results highlight the potential of UAV multispectral imagery to monitor the AGB variation within the footprint of the flux tower and highlight the need for repeated field sampling with a precise geolocation to improve the matching between the flight and the field surveys. [less ▲]

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See detailSun-Earth Interaction
Grodent, Denis ULiege

Learning material (2017)

Sun-Earth Interaction

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See detailRadiative Transfer
Grodent, Denis ULiege

Learning material (2017)

Radiative Transfer

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See detailLiaison externe et soignants du domicile: symphonie et fausses notes
Belche, Jean Luc ULiege

Conference (2017, October 20)

Analyser le processus en cours pour mieux le comprendre.

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See detailDo Property Rights and Equality Make Good Bedfellows ? European perspective
Grandjean, Geoffrey ULiege

Conference (2017, October 20)

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See detailLieu de vie, lieu de travail. L'institution et le bien-être
Nisen, Laurent ULiege

Conference (2017, October 20)

Présentation de la session Braises consacrée au bien-être (des travailleurs, des résidents) en institution

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See detailQuelques en questions en lien avec la loi du 12 janvier 2007
Mormont, Hugo ULiege

Conference given outside the academic context (2017)

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See detailESTROGEN RECEPTORS AND ESTETROL-DEPENDENT NEUROPROTECTIVE ACTIONS: A PILOT STUDY
Tskitishvili, Ekaterine ULiege; Pequeux, Christel ULiege; Munaut, Carine ULiege et al

Conference (2017, October 20)

Context: Estetrol (E4) has strong antioxidative, neurogenic and angiogenic effects in neural system resulting in the attenuation of neonatal hypoxic–ischemic encephalopathy. Objective: We aimed to define ... [more ▼]

Context: Estetrol (E4) has strong antioxidative, neurogenic and angiogenic effects in neural system resulting in the attenuation of neonatal hypoxic–ischemic encephalopathy. Objective: We aimed to define the role of estrogen receptors in E4-dependent actions in neuronal cell cultures and prove the promyelinating effect of E4. Methods: In vitro the antioxidative and cell survival/proliferating effects of E4 on H2O2-induced oxidative stress in primary hippocampal cell cultures were studied using different combinations of specific inhibitors for ERα (MPP dihydrochloride), ERβ (PHTTP), GPR30 (G15) and palmytoilation (2-BR). LDH activity and cell survival assays were performed. In vivo the promyelinating role of different concentrations of E4 (1 mg/kg/day, 5 mg/kg/day, 10 mg/kg/day, 50 mg/kg/day) was investigated using the hypoxic–ischemic brain damage model in the 7-day-old immature rats before/after the induction of hypoxic–ischemic insult. Myelin basic protein (MBP) immunostaining was performed on brain coronal sections. Results: Our results show that LDH activity is significantly upregulated in cell cultures where the E4’s effect was completely blocked by concomitant treatment either with ERα and ERβ inhibitors (MPP and PHTPP, respectively), or ERα and ERβ inhibitors combined with 2-BR. Cell survival is significantly downregulated in cell cultures where the effect of E4 was blocked by ERβ inhibitor (PHTTP) alone. The blockage of GRP30 receptor did affect neither LDH activity nor cell survival. MBP immunostaining is significantly upregulated in E4-pretreated groups at a concentration of 5 mg/kg/day and 50 mg/kg/day E4, whereas the MBP-positive area OD ratio is significantly increased in all the E4-treated groups. Conclusions: E4’s antioxidative actions mostly depend on ERα and ERβ, whereas neurogenesis and possibly promyelinating activities might be realized through ERβ. [less ▲]

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See detailDes femmes face aux hommes de métier : concevoir et bâtir des monastères féminins sur la dorsale catholique (17e-18e s.)
Piront, Julie ULiege

Conference (2017, October 20)

Dans les années qui suivent leur établissement en milieu urbain, les religieuses sont amenées à aménager puis à ériger des bâtiments conventuels conformes à leurs besoins et à leur mode de vie. Malgré la ... [more ▼]

Dans les années qui suivent leur établissement en milieu urbain, les religieuses sont amenées à aménager puis à ériger des bâtiments conventuels conformes à leurs besoins et à leur mode de vie. Malgré la stricte clôture que leur impose le concile de Trente, les religieuses se doivent de faire appel à des professionnels du bâti et de passer des contrats avec une main d’œuvre généralement masculine, qu’il s’agisse d’architectes, d’entrepreneurs ou d’artisans. Cette communication propose d’analyser la manière dont différentes congrégations religieuses implantées sur la « dorsale catholique » (annonciades célestes, bénédictines de la Paix Notre-Dame, ...) sont parvenues à recruter ces hommes de terrain, à guider la conception du plan, à surveiller le déroulement du chantier et le cas échéant, à affirmer leurs compétences. Dans un premier temps, sera analysé le discours normatif des règles et constitutions qui encadrent ces rapports avant de les confronter, dans un second temps, aux témoignages et au vécu de ces femmes livrés par leurs écrits (chroniques, annales, biographies de religieuses) aux XVIIe et XVIIIe siècles, inédits pour la plupart. [less ▲]

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See detailBeech phenology and productivity at the Vielsalm Terrestrial Observatory
Hurdebise, Quentin ULiege; Vincke, Caroline; De Ligne, Anne ULiege et al

Poster (2017, October 20)

Temperate forests, as other ecosystems and oceans, mitigate the accumulation in the atmosphere of CO2, the main responsible for the current climate change. It is, therefore, a necessity to understand how ... [more ▼]

Temperate forests, as other ecosystems and oceans, mitigate the accumulation in the atmosphere of CO2, the main responsible for the current climate change. It is, therefore, a necessity to understand how these forests react and will react in a changing environment. That requires long-term simultaneous monitoring of the forest productivity and phenology as well as of climatic variables. Using the 20 years dataset from the Vielsalm Terrestrial Observatory (VTO), an eddy covariance site located in a mixed forest in east Belgium and dominated by beeches, the relations between phenological and productivity indicators were analyzed. Phenological indicators (leaf out beginning, duration and ending as well as leaf fall date) were derived from the relative light transmissivity through the canopy and from the temporal dynamic of the Net Ecosystem Productivity (NEP). No trend was observed for these indicators during the last two decades, but significant relations were found between them and between them and climatic variables. Productivity indicators were derived from eddy covariance measurements (NEP), tree ring widths (growth index) and masting intensity. Growth index was significantly related to the NEP and a reverse proportionality to the masting intensity was found. The analysis of the relation between the beech stand NEP and the phenology gives us evidences that annual NEP is significantly related to the length of the carbon uptake period. A model combining the length of the carbon uptake period and the photosynthetic capacity of the ecosystem was able to predict more than two third of the interannual variability at the VTO. This work underlines the multiplicity of the relation between phenological and productivity indicators. [less ▲]

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See detailEnvironmental controls of methanol emissions from a grazed grassland in Dorinne, Belgium
Michel, Colin ULiege; Heinesch, Bernard ULiege; Bachy, Aurélie ULiege et al

Poster (2017, October 20)

Despite the growing interest for oxygenated volatile organic compounds (OVOC) over the last 15 years due to their role in the atmospheric chemistry, current knowledge about OVOC exchanges by grassland and ... [more ▼]

Despite the growing interest for oxygenated volatile organic compounds (OVOC) over the last 15 years due to their role in the atmospheric chemistry, current knowledge about OVOC exchanges by grassland and the environmental factors driving them remains lacunar. However, those ecosystems represent an important part of the total earth surface (13.37%). This study conducted on a grazed grassland therefore aims to quantify OVOC exchanges over full grazing seasons in order to understand the mechanisms behind these exchanges. It took place within the activities of the CROSTVOC project (CROp Stress VOC) and therefore gives an important attention to the stress induced fluxes. BVOC flux measurements were performed with a PTR-MS for the measurements of OVOC mixing ratios on two different scales: the eddy Covariance method was used during two whole grazing seasons (2014 and 2015) and in the 2016 summer, measurements were also performed on a smaller scale by using all-teflon automated dynamic chambers. The chambers allowed measuring accurately the impact of grazing by following simultaneously undisturbed and grazed grassland patches. This study pointed out that several OVOC were exchanged in variable quantities, with methanol being by far the most important. Methanol fluxes exhibited a clear diurnal cycle with close-to-zero fluxes at night and maximum fluxes at midday. The flux was also much larger in the summer than during autumn or spring. For the eddy Covariance data, the average methanol flux in the summer (0.033 μg.m-2s-1) was in the same range of other studies, being lower than the average found by Bamberger et al. in 2010 (0.080 μg.m-2s-1) and by Ammann (0.077 μg.m-2s-1). Fluxes from the chambers were slightly lower with an average value of 0.27 μg.m-2s-1 but they were measured in the late summer. Driver analysis is still ongoing but first results showed that the flux was strongly correlated at short time scale (half hourly for the EC method and one and a half hourly for the chambers) to the photosynthetic photon flux density and the latent heat flux. We believe that their influence comes mainly from the control practiced by stomatal conductance in non-steady state conditions and expansion of cell walls in steady state conditions. The cuvette data showed that grazing resulted in significantly enhanced emissions of methanol that lasted for several days. On the contrary, the eddy Covariance method cannot distinguish between grazed and non-grazed grass and only a small fraction of the method footprint had been grazed the previous days on average. Our eddy-covariance data suggested that an increase in the stocking density did not contribute to a significant rise of methanol emission. The limited variability in stocking density during the two growing seasons and the more powerful effect of other drivers likely induced that the flux variability due to the SD was too low to be measured by the eddy Covariance method. In depth comparisons between the eddy-covariance data and the dynamic chambers data will be carried out. [less ▲]

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See detailLooking for Smaug and the golden mountain. Are fictional objects Kripkean or Meinongian?
Leclercq, Bruno ULiege

Conference (2017, October 20)

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