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See detail1967-2007 : 40 ans pour le Livre blanc
Burny, Philippe ULg; De Proft, Michel

Article for general public (2007)

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See detail1969. J.J. Oversteegen: Vorm of vent. Opvattingen over de aard van het literaire werk in de Nederlandse kritiek tussen de twee wereldoorlogen
Spinoy, Erik ULg

in Internationale Neerlandistiek (2012), 50(special issue), 24-26

This is a short article evaluating a key contribution to the development of literary theory in the Dutch-speaking domain. The central thesis of the article is that the book under scrutiny is considerable ... [more ▼]

This is a short article evaluating a key contribution to the development of literary theory in the Dutch-speaking domain. The central thesis of the article is that the book under scrutiny is considerable more conservative and influenced by earlier views of literature than was originally acknowledged. [less ▲]

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See detail1978CA and 1978DA
Surdej, Jean ULg; Surdej, Anna ULg

in IAU Astronomical Telegram Nø 3185 (1978)

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See detailThe 1979-2005 Greenland ice sheet melt extent from passive microwave data using an improved version of the melt retrieval XPGR algorithm
Fettweis, Xavier ULg

Poster (2007, April 16)

Analysis of passive microwave satellite observations over the Greenland ice sheet reveals a significant increase in surface melt over the period 1979-2005. Since 1979, the total melt area was found to ... [more ▼]

Analysis of passive microwave satellite observations over the Greenland ice sheet reveals a significant increase in surface melt over the period 1979-2005. Since 1979, the total melt area was found to have increased +1.22 x 10ˆ7 kmˆ2. An improved version of the cross-polarized gradient ratio (XPGR) technique is used to identify the melt from the brightness temperatures. The improvements in the melt retrieval XPGR algorithm as well as the surface melt acceleration are discussed with results from a coupled atmosphere-snow regional climate model. From 1979 to 2005, the ablation period increases everywhere over the melt zone except in the regions where the model simulates an increased summer snowfall. Indeed, more snowfall in summer decreases the liquid water content of the snowpack, raises the albedo and therefore reduces the melt. Finally, this melt acceleration over the Greenland ice sheet is highly correlated with both Greenland and global warming suggesting a continuing surface melt increase in the future. [less ▲]

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See detailThe 1979–2005 Greenland ice sheet melt extent from passive microwave data using an improved version of the melt retrieval XPGR algorithm
Fettweis, Xavier ULg; van Ypersele, Jean-Pascal; Gallée, Hubert et al

in Geophysical Research Letters (2007)

Analysis of passive microwave satellite observations over the Greenland ice sheet reveals a significant increase in surface melt over the period 1979–2005. Since 1979, the total melt area was found to ... [more ▼]

Analysis of passive microwave satellite observations over the Greenland ice sheet reveals a significant increase in surface melt over the period 1979–2005. Since 1979, the total melt area was found to have increased by +1.22 × 107 km2. An improved version of the cross-polarized gradient ratio (XPGR) technique is used to identify the melt from the brightness temperatures. The improvements in the melt retrieval XPGR algorithm as well as the surface melt acceleration are discussed with results from a coupled atmosphere-snow regional climate model. From 1979 to 2005, the ablation period has been increasing everywhere over the melt zone except in the regions where the model simulates an increased summer snowfall. Indeed, more snowfall in summer decreases the liquid water content of the snowpack, raises the albedo and therefore reduces the melt. Finally, the observed melt acceleration over the Greenland ice sheet is highly correlated with both Greenland and global warming suggesting a continuing surface melt increase in the future. [less ▲]

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See detail1984 N1
Hafner, R.; Manfroid, Jean ULg

in International Astronomical Union Circulars [=IAUCs] (1984), 3968

IAUC 3968 available at Central Bureau for Astronomical Telegrams.

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See detailThe 1985 chlorine and fluorine inventories in the stratosphere based on atmos observations at 30-degrees north latitude
Zander, Rodolphe ULg; Gunson, Michael R.; Farmer, Crofton B. et al

in Journal of Atmospheric Chemistry (1992), 15(2), 171-186

The set of high-resolution infrared solar observations made with the Atmospheric Trace Molecule Spectroscopy (ATMOS) - Fourier transform spectrometer from onboard Spacelab 3 (30 April-1 May 1985) has been ... [more ▼]

The set of high-resolution infrared solar observations made with the Atmospheric Trace Molecule Spectroscopy (ATMOS) - Fourier transform spectrometer from onboard Spacelab 3 (30 April-1 May 1985) has been used to evaluate the total budgets of the odd chlorine and fluorine chemical families in the stratosphere. These budgets are based on volume mixing ratio profiles measured for HCl, HF, CH3Cl, ClONO2, CCl4, CCl2F2, CCl3F, CHClF2, CF4, COF2, and SF6, near 30-degrees north latitude. When including realistic concentrations for species not measured by ATMOS, i.e., the source gases CH3CCl3, and C2F3Cl3 below 25 km, and the reservoirs ClO, HOCl and COFCl between 15 and 40 km (five gases actually measured by other techniques), the 30-degrees-N zonal 1985 mean total mixing ratio of chlorine, Cl, was found to be equal to (2.58 +/- 0.10) ppbv (parts per billion by volume) throughout the stratosphere, with no significant decrease near the stratopause. The results for total fluorine indicate a slight, but steady, decrease of its volume mixing ratio with increasing altitude, around a mean stratospheric value of (1.15 +/- 0.12) ppbv. Both uncertainties correspond to one standard deviation. These mean springtime 1985 stratospheric budgets are commensurate with values reported for the tropospheric Cl and F concentrations in the early 1980s, when allowance is made for the growth rates of their source gases at the ground and the time required for tropospheric air to be transported into the stratosphere. The results are discussed with emphasis on conservation of fluorine and chlorine and the partitioning among source, sink, and reservoir gases throughout the stratosphere. [less ▲]

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See detailThe 1988-2003 Greenland ice sheet melt extent by passive microwave satellite data and a regional climate model
Fettweis, Xavier ULg; Gallée, Hubert; Lefebre, Filip et al

in Climate Dynamics (2006), 27(5), 531-541

Measurements from ETH-Camp and JAR1 AWS (West Greenland) as well as coupled atmosphere-snow regional climate simulations have highlighted flaws in the cross-polarized gradient ratio (XPGR) technique used ... [more ▼]

Measurements from ETH-Camp and JAR1 AWS (West Greenland) as well as coupled atmosphere-snow regional climate simulations have highlighted flaws in the cross-polarized gradient ratio (XPGR) technique used to identify melt from passive microwave satellite data. It was found that dense clouds (causing notably rainfall) on the ice sheet severely perturb the XPGR melt signal. Therefore, the original XPGR melt detection algorithm has been adapted to better incorporate atmospheric variability over the ice sheet and an updated melt trend for the 1988–2003 period has been calculated. Compared to the original algorithm, the melt zone area increase is eight times higher (from 0.2 to 1.7% year−1). The increase is higher with the improved XPGR technique because rainfall also increased during this period. It is correlated to higher atmospheric temperatures. Finally, the model shows that the total ice sheet runoff is directly proportional to the melt extent surface detected by satellites. These results are important for the understanding of the effect of Greenland melting on the stability of the thermohaline circulation. [less ▲]

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See detailThe 1991 EGAS Conference in Torun
Biémont, Emile ULg; Werth, G.

in Europhysics News (1991), 22

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See detailThe 1994 northern midlatitude budget of stratospheric chlorine derived from ATMOS/ATLAS-3 observations
Zander, Rodolphe ULg; Mahieu, Emmanuel ULg; Gunson, M. R. et al

in Geophysical Research Letters (1996), 23(17), 2357-2360

Volume mixing ratio (VMR) profiles of the chlorine-bearing gases HCl, ClONO2, CCl3F, CCl2F2, CHClF2, CCl4, and CH3Cl have been measured between 3 and 49 degrees northern- and 65 to 72 degrees southern ... [more ▼]

Volume mixing ratio (VMR) profiles of the chlorine-bearing gases HCl, ClONO2, CCl3F, CCl2F2, CHClF2, CCl4, and CH3Cl have been measured between 3 and 49 degrees northern- and 65 to 72 degrees southern latitudes with the Atmospheric Trace MOlecule Spectroscopy (ATMOS) instrument during the ATmospheric Laboratory for Applications and Science (ATLAS)-3 shuttle mission of 3 to 12 November 1994. A subset of these profiles obtained between 20 and 49 degrees N at sunset, combined with ClO profiles measured by the Millimeter-wave Atmospheric Sounder (MAS) also from aboard ATLAS-3, measurements by balloon for HOCl, CH3CCl3 and C2Cl3F3, and model calculations for COClF indicates that the mean burden of chlorine, Cl-TOT, was equal to (3.53 +/- 0.10) ppbv (parts per billion by volume), 1-sigma, throughout the stratosphere at the time of the ATLAS 3 mission. This is some 37% larger than the mean 2.58 ppbv value measured by ATMOS within the same latitude zone during the Spacelab 3 flight of 29 April to 6 May 1985, consitent with an exponential growth rate of the chlorine loading in the stratosphere equal to 3.3%/yr or a linear increase of 0.10 ppbv/yr over the Spring-1985 to Fall-1994 time period. These findings are in agreement with both the burden and increase of the main anthropogenic Cl-bearing source gases at the surface during the 1980s, confirming that the stratospheric chlorine loading is primarily of anthropogenic origin. [less ▲]

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See detail1995, Fourth Catalogue of stars measured in the Long-Term Photometry of Variables project.
Sterken, C.; Manfroid, Jean ULg; Beele, D. et al

Book published by ESO (1995)

Not Available

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See detail1997 : deux colloques pour célébrer un savant
Rochette, Bruno ULg

in Bulletin de la Fédération des Professeurs de Grec et de Latin [=FPGL] (1998), 111(Janvier), 3-4

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See detail1997–2007 CO trend at the high Alpine site Jungfraujoch: a comparison between NDIR surface in situ and FTIR remote sensing observations
Dils, B.; Cui, J.; Henne, S. et al

in Atmospheric Chemistry and Physics (2011), 11(13), 6735--6748

Within the atmospheric research community, there is a strong interest in integrated datasets, combining data from several instrumentations. This integration is complicated by the different characteristics ... [more ▼]

Within the atmospheric research community, there is a strong interest in integrated datasets, combining data from several instrumentations. This integration is complicated by the different characteristics of the datasets, inherent to the measurement techniques. Here we have compared two carbon monoxide time series (1997 till 2007) acquired at the high-Alpine research station Jungfraujoch (3580 m above sea level), with two well-established measurement techniques, namely in situ surface concentration measurements using Non-Dispersive Infrared Absorption technology (NDIR), and ground-based remote sensing measurements using solar absorption Fourier Transform Infrared spectrometry (FTIR). The profile information available in the FTIR signal allowed us to extract an independent layer with a top height of 7.18 km above sea level, appropriate for comparison with our in situ measurements. We show that, even if both techniques are able to measure free troposphere CO concentrations, the datasets exhibit marked differences in their overall trends (−3.21 ± 0.03 ppb/year for NDIR vs. −0.8 ± 0.4 ppb/year for FTIR). Removing measurements that are polluted by uprising boundary layer air has a strong impact on the NDIR trend (now −2.62 ± 0.03 ppb/year), but its difference with FTIR remains significant. Using the LAGRANTO trajectory model, we show that both measurement techniques are influenced by different source regions and therefore are likely subject to exhibit significant differences in their overall trend behaviour. However the observation that the NDIR-FTIR trend difference is as significant before as after 2001 is at odds with available emission databases which claim a significant Asian CO increase after 2001 only. [less ▲]

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See detail1D and 2D solvers coupling for free surface flow modelling
Erpicum, Sébastien ULg; Archambeau, Pierre ULg; Dewals, Benjamin ULg et al

in Proceedings of the 7th International Conference on Hydroinformatics (2006)

In the field of hydraulic engineering, the size of the simulations is one of the current challenges to model with precision the large areas involved by practical engineers applications. In this scope, the ... [more ▼]

In the field of hydraulic engineering, the size of the simulations is one of the current challenges to model with precision the large areas involved by practical engineers applications. In this scope, the linking in the same modelization of different solvers, each one used in the part of the simulation where its fundamental characteristics are most suitable, open the door to still unreached modelling possibilities. WOLF software includes a series of numerical tools for simulating a wide range of free surface flows and transport phenomena. This paper presents the coupling of the 1D and 2D multiblock finite volume models of WOLF to simulate in a unified way large river reaches (in 1D) with a very fine computation of local areas (in 2D). An application to the simulation of the propagation of the waves following the filling and emptying operations of a large locks system on a several kilometres long reach of the river Meuse (Belgium) is presented. [less ▲]

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See detail1D Ising model for ripple formation
Vandewalle, Nicolas ULg; Galam, S.

in Journal of Physics : A Mathematical & General (2000), 33(28), 4955-4962

A 1D Ising model is shown to reproduce qualitatively the dynamics of ripple formation. The saltation effect is imposed using a Kawasaki dynamics and a pair interaction over some distance E. Within this ... [more ▼]

A 1D Ising model is shown to reproduce qualitatively the dynamics of ripple formation. The saltation effect is imposed using a Kawasaki dynamics and a pair interaction over some distance E. Within this model, the ripple state turns out to be metastable, in agreement with cellular automata simulations as well as recent underwater experiments. A dynamical phase diagram is obtained. A mean-field solution of the problem is given in terms of the ripple size. A mapping is then performed onto a 2D E x infinity static problem. [less ▲]

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See detail1D many-body quantum transport of Bose-Einstein condensates : a truncated Wigner approach
Dujardin, Julien ULg; Argüelles Parra, Arturo ULg; Schlagheck, Peter ULg

Poster (2012, March 29)

We calculate the transport properties of an ultracold gas of Bose- Einstein condensed atoms that is coupled from a magnetic trap into a one-dimensional waveguide. A central aim of such guided atom lasers ... [more ▼]

We calculate the transport properties of an ultracold gas of Bose- Einstein condensed atoms that is coupled from a magnetic trap into a one-dimensional waveguide. A central aim of such guided atom lasers is to study the role of atom-atom interaction in many-body transport processes across finite scattering regions within the waveguide resembling tunnel junctions and quantum dots. Our numerical approach to solve this many-body scattering problem is based on a home-made theory where the boundaries of the system are simulating an open system enabling us to calulate observable in the steady-state regime such as density, current, transmission. The results are compared to the mean-field regime. [less ▲]

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See detail1D numerical approach to model the flow over a piano key weir (PKW)
Erpicum, Sébastien ULg; Machiels, Olivier ULg; Archambeau, Pierre ULg et al

in Proc. Int. Conf. SimHydro 2010: Hydraulic modeling and uncertainty (2010)

Piano Key Weir (PKW) is a new type of weir showing appealing hydraulic capacities, in particular for low heads. However, its complex geometry, with a large set of parameters, makes difficult the ... [more ▼]

Piano Key Weir (PKW) is a new type of weir showing appealing hydraulic capacities, in particular for low heads. However, its complex geometry, with a large set of parameters, makes difficult the understanding of the flow features and consequently the definition of an optimal design. In this paper, we investigate how a 1D numerical approach can predict the flow over a PKW and thus help in identifying the most relevant geometric parameters. After a detailed description of the numerical model, a comparison of the numerical results with experimental data is realized, showing promising results. [less ▲]

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See detail1D numerical modeling of the flow over a Piano Key Weir
Erpicum, Sébastien ULg; Machiels, Olivier ULg; Archambeau, Pierre ULg et al

in Erpicum, Sébastien; Laugier, Frédéric; Boillat, Jean Louis (Eds.) et al Labyrinth and Piano Key Weirs - PKW 2011 (2011)

Because of the PK-Weir geometric specificities, its hydraulic capacity remains difficult to predict without using experimental techniques. A 1D numerical model of the flow over a PK-Weir has been ... [more ▼]

Because of the PK-Weir geometric specificities, its hydraulic capacity remains difficult to predict without using experimental techniques. A 1D numerical model of the flow over a PK-Weir has been developed at the Research unit HACH at the University of Liege. It is based on a 1D modeling of the inlet and the outlet separately, with a single upstream reservoir and interactions between both flows by exchange of mass and momentum along the lateral crest. The comparison of the numerical results with various experimental data showed the ability of the numerical model to predict with reasonable accuracy the release capacity of a PK-Weir, whatever its geometry. The tests of the solver enable to highlight the significant influence of the inlet and outlet width on the weir release capacity. They also suggest that improvements of the numerical model may lie in the evaluation of the discharge coefficient of the lateral crest. [less ▲]

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See detail1D Organization of ZnO and TiO2 nanoparticles toward advanced photonic and photocatalytic materials
Kinadjian, Natacha ULg; Achard, Marie-France; Julian-Lopez, Beatriz et al

Poster (2012, October)

Nowadays Chemist are request to construct more and more complex architectures bearing multifunctionalities enable to respond to external stimuli. The construction of such complex architectures will be ... [more ▼]

Nowadays Chemist are request to construct more and more complex architectures bearing multifunctionalities enable to respond to external stimuli. The construction of such complex architectures will be addressed through strong interplay in chemical science, as proposed recently with the concept of integrative Chemistry.[1] We synthesized PVA/ZnO-nanorods composite fibers using co-axial flux extrusion.[2] These fibers exhibit higher anisotropic photonic properties, both in absorption and emission, as a result of the collective alignment of the ZnO nanorods along the main axis of the PVA fiber. This photonic anisotropy is triggered by a synergistic interaction between the PVA matrix, stretched above Tg, and cooled down under strain. Compared with non-elongated fibers that present an isotropic emission, composite fibers previously submitted to a tensile stress absorb selectively UV emission when the polarized laser beam is parallel to the main axis of the fiber. In addition, their photolumincescence is also anisotropic, with a waveguide behavior along the main axis of the fiber. Mechanical properties of these composite fibers are also drastically improved, compared with pure PVA fibers: the longitudinal Young modulus of these fibers is increased from 2 to 6 GPa upon ZnO addition, a value similar to those already observed for composite fibers, prepared either with carbon nanotubes, or Vanadium Oxide macroscopic fibers. [1] N. Brun, S. Ungureanu, H. Deleuze and R. Backov. Chem. Soc. Rev., 2011, 40, 771 [2] Kinadjian, N., Achard, M.-F., Julián-López, B., Maugey, M., Poulin, P., Prouzet, E. and Backov, R. (2012). Adv. Funct. Mater.. doi: 10.1002/adfm.201200360 [less ▲]

Detailed reference viewed: 24 (2 ULg)