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See detailL'Enéide des papyrus. Le destin d'une oeuvre littéraire en Egypte gréco-romaine
Rochette, Bruno ULiege

Master's dissertation (1987)

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See detailEnemy at the (Flood) Gates: EU ‘Exceptionalism’ in Recent Tensions with the International Protection of Social Rights
Rocca, Marco ULiege

in European Labour Law Journal (2016), 7(1), 52-81

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See detailEnergetic and conformational study of four benzylimidazole compounds with alpha 2 agonist profile: The mivazerol and three methylated derivatives
Vancampenhout, Nathalie; Dive, Georges ULiege; Dehareng, Dominique ULiege

in International Journal of Quantum Chemistry (1996), 60(4), 911-930

The mivazerol and three of its methylated derivatives are studied at the ab initio SCF level within the MINI-1 and 6-31G basis sets. This study aimed at determining some probable conformations, either ... [more ▼]

The mivazerol and three of its methylated derivatives are studied at the ab initio SCF level within the MINI-1 and 6-31G basis sets. This study aimed at determining some probable conformations, either neutral or protonated, that could interact with the alpha 2 adrenoceptors. The solvent effect was also studied within the Onsager's solvent model at the two dielectric constant (epsilon) values of 4 and 80. The interaction with the environment (either solvent or receptor) is schematically studied by positioning either two water molecules or one formamide or/and one formic add near the amide and the imidazole for few isomers. The medium polarization, through epsilon, and the solvation effect, through the interaction with the solvent molecules or the receptor side chains, stabilize the same isomers. Post-SCF calculations are performed at the CISD level, the first excited singlet and triplet states energies are determined, and the question of the wave-function stability is addressed. The results indicate the probability of a spin-orbit coupling with the first excited triplet state, thus opening the question of such a possibility within an enzyme active site. (C) 1996 John Wiley & Sons, Inc. [less ▲]

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See detailEnergetic and Environmental Aspects of a Diesel Engine Using Rapeseed Oil as Fuel
Christiaens, Sébastien; Bruylants, Grégory; Ngendakumana, Philippe ULiege

in 19th International Conference on Efficiency, Cost, Optimization , Simulation and Environmental Impact of Energy Systems (ECOS 2006) (2006, July)

This paper describes the experiment that was carried out at the Thermodynamics Laboratory of the University of Liège (Belgium) to study the impact of the use of vegetable oil as a substitute for light oil ... [more ▼]

This paper describes the experiment that was carried out at the Thermodynamics Laboratory of the University of Liège (Belgium) to study the impact of the use of vegetable oil as a substitute for light oil on the short-term performance of Diesel engines for cars. The vegetable oil selected is derived directly from rapeseed without any refinement processes. Five tests were carried out, going from 0% rapeseed oil blended in conventional Diesel fuel (reference fuel) up to 100% rapeseed oil. For each test, the whole operating range of the engine was swept and the fuel consumption and exhaust emissions measured simultaneously. The study concludes that the engine used during the research can be run with 100% unrefined rapeseed oil. Nevertheless, using 100% oil is not considered as a valid large scale solution. However, using a smaller percentage of rapeseed oil gives promising results in terms of reduction of CO2 emission as well as reduction of the opacity of the exhaust gases. [less ▲]

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See detailEnergetic and Environmental Performances of a Domestic Hot Water Condensing Boiler Fired by Wood Pellets
Ngendakumana, Philippe ULiege; Gabriele, Fabian; Restivo, Yannick et al

in Energy Procedia (2017)

In order to assess the performances of the domestic heating boilers with a CE mark, a wood pellets fired condensing boiler has been purchased and installed in the Laboratory for tests. The objective of ... [more ▼]

In order to assess the performances of the domestic heating boilers with a CE mark, a wood pellets fired condensing boiler has been purchased and installed in the Laboratory for tests. The objective of the study was not only to check the announced performances, but mainly to investigate the influence of the different parameters affecting the functioning of the boiler, the thermal efficiency and the pollutants (NOx and CO) emission being aimed at. Tests have been performed to study the influence of the cycling frequency of the burner functioning, the overall excess air, the return water temperature, and the output power of the boiler. As announced by the manufacturer, the tested boiler fulfils the requirements of the Blue Angel Label, but the recommended value for the excess air (1.2) can be reduced to a value of about 0.4 without excessive emissions of CO. The boiler could perform better if the ON period of the cycle of the burner is increased even better if the OFF period is suppressed. The NOx are mainly formed from the nitrogen content of the pellets and their emissions can only be reduced by a lower nitrogen content of the pellets than the limit stated in the standard. Random peaks observed in the evolution of CO, the boiler being operating in steady state regime, are attributed to the combustion process of pellets which is a non-continuous process by nature. [less ▲]

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See detailEnergetic approach for the characterization of taps in granular compaction
Ludewig, François ULiege; Dorbolo, Stéphane ULiege; Gilet, Tristan ULiege et al

in Europhysics Letters [=EPL] (2008), 84(4),

We report numerical investigations for the compaction dynamics of dense granular assemblies. The studies are based on the non-smooth contact dynamics model. Our work suggests that the dimensionless ... [more ▼]

We report numerical investigations for the compaction dynamics of dense granular assemblies. The studies are based on the non-smooth contact dynamics model. Our work suggests that the dimensionless acceleration parameter Gamma, used by a large majortiy of authors, is not appropriate for rescaling the data. We prove that the dimensionless energy Xi, injected in the granular system at lift-off, is more appropriate and leads to robust interpretations of the compaction dynamics. Indeed, the injected energy allows to pass energy barriers that separate local equilibrium states. Using the Eyring picture of relaxation dynamic, we show that the consideration of Xi leads to a new law for compaction. [less ▲]

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See detailEnergetic Aspects of Non-Radial Solar-Like Oscillations in Red Giants
Dupret, Marc-Antoine ULiege; Belkacem, Kevin; Montalbán, Josefina et al

in Astrophysics and Space Science Proceedings (2012)

The non-radial oscillations discovered by CoRoT (see e.g. de Ridder et al. (2009)) and by Kepler(see e.g. Bedding et al. (2010)) in thousands of red giants constitute a wonderful mine of information to ... [more ▼]

The non-radial oscillations discovered by CoRoT (see e.g. de Ridder et al. (2009)) and by Kepler(see e.g. Bedding et al. (2010)) in thousands of red giants constitute a wonderful mine of information to determine their global characteristics and probe their internal structure. A. Miglio and J. Montalbán have presented in detail in this conference the seismic structure of red giants, the information hold by their oscillation frequencies, and how it can be used. An adiabatic analysis of the oscillations was sufficient at this level as the frequencies are mainly determined by the deep layers were the oscillatons are quasi-adiabatic. We consider here energetic aspects of non-radial oscillations in red-giants. Non-adiabatic models of solar-like oscillations are required to determine the theoretical amplitude and lifetimes of the modes. These parameters allow us to determine how power spectra are expected to look like, depending on the structure of the red giant. Comparison with the observed measures gives thus additional constraints on the models. [less ▲]

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See detailEnergetic coupling between plastids and mitochondria drives CO assimilation in diatoms.
Bailleul, Benjamin; Berne, Nicolas ULiege; Murik, Omer et al

in Nature (2015)

Diatoms are one of the most ecologically successful classes of photosynthetic marine eukaryotes in the contemporary oceans. Over the past 30 million years, they have helped to moderate Earth's climate by ... [more ▼]

Diatoms are one of the most ecologically successful classes of photosynthetic marine eukaryotes in the contemporary oceans. Over the past 30 million years, they have helped to moderate Earth's climate by absorbing carbon dioxide from the atmosphere, sequestering it via the biological carbon pump and ultimately burying organic carbon in the lithosphere. The proportion of planetary primary production by diatoms in the modern oceans is roughly equivalent to that of terrestrial rainforests. In photosynthesis, the efficient conversion of carbon dioxide into organic matter requires a tight control of the ATP/NADPH ratio which, in other photosynthetic organisms, relies principally on a range of plastid-localized ATP generating processes. Here we show that diatoms regulate ATP/NADPH through extensive energetic exchanges between plastids and mitochondria. This interaction comprises the re-routing of reducing power generated in the plastid towards mitochondria and the import of mitochondrial ATP into the plastid, and is mandatory for optimized carbon fixation and growth. We propose that the process may have contributed to the ecological success of diatoms in the ocean. [less ▲]

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See detailEnergetic effects in classical pulsators
Dupret, Marc-Antoine ULiege; Grigahcène, A.; Théado, S. et al

in Proceedings of SOHO 18/GONG 2006/HELAS I, Beyond the spherical Sun (2006, October 01)

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See detailEnergetic ion composition during reconfiguration events in the Jovian magnetotail
Radioti, Aikaterini ULiege; Woch, J.; Kronberg, E. A. et al

in Journal of Geophysical Research. Space Physics (2007), 112(A6),

[1] On the basis of the first 15 orbits of the Galileo spacecraft the composition of the energetic ion population of the Jovian magnetosphere is studied on a global scale. Analyzing data from the ... [more ▼]

[1] On the basis of the first 15 orbits of the Galileo spacecraft the composition of the energetic ion population of the Jovian magnetosphere is studied on a global scale. Analyzing data from the energetic particles detector onboard Galileo, we study the relative ion abundance ratios of S/O, S/He, O/He and p/He at various energy/ nucleon values. Prominent enhancements of S/O, S/He, and O/He abundance ratios are observed in the predawn sector and are associated with substorm-like events in the Jovian magnetotail. During these reconfiguration events, frequent small-scale variations of the south-north component of the magnetic field are present. Acceleration by such magnetic field variations is examined as a possible mechanism for particle energization in that region. When the timescale of the magnetic field variation is comparable to the particle gyro period, the particle is accelerated by the induced electric field. It is shown that, during the Jovian substorm-like events, the heavier ions are more efficiently energized than the lighter leading to the observed ion abundances. Ion composition measurements in other parts of the magnetosphere have shown quasiperiodic 3-day modulations suggesting that the internally driven processes affect the ion composition in the whole magnetosphere. [less ▲]

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See detailEnergetic oxygen atoms in the polar geocorona
Shematovich, V. I.; Bisikalo, D. V.; Gérard, Jean-Claude ULiege

in Journal of Geophysical Research. Space Physics (2006), 111

The role of the auroral sources induced by the electron and proton precipitation in the formation of the hot oxygen corona in the polar upper atmosphere is studied. It is found that both electron ... [more ▼]

The role of the auroral sources induced by the electron and proton precipitation in the formation of the hot oxygen corona in the polar upper atmosphere is studied. It is found that both electron precipitation through exothermic chemistry and proton precipitation through atmospheric sputtering significantly contribute to the population of the hot oxygen geocorona. It is also found that only atmospheric sputtering results in the formation of the escape flux of energetic oxygen atoms, providing an important source of heavy atoms for the magnetosphere. The exothermic chemistry induced by the electron precipitation and/or by the absorption of the solar UV radiation is operating continuously in the polar upper atmosphere and results in a steady population of the very near-Earth environment by suprathermal oxygen atoms with energies below a few eV. By contrast, atmospheric sputtering by magnetospheric protons provides a more variable contribution, strongly coupled with the cusp region. It produces the more energetic oxygen atoms that populate the external regions of the hot oxygen geocorona. The results of calculations are in a good agreement with the analysis of the low-latitude perigee Low Energy Neutral Atom (LENA) images showing that the instrument signal consists of low to medium energy (5-30 eV) oxygen atoms produced in and near the cusp region. The more energetic (>30 eV) fraction of energetic oxygen atoms produced by the ion-induced atmospheric sputtering could be responsible for the energetic neutrals observed by the instrument far away from the cusp or oval regions. The total escape flux of oxygen atoms associated with atmospheric sputtering by protons is found about 8 × 10[SUP]23[/SUP] s[SUP]-1[/SUP] therefore this mechanism may provide a substantial contribution to the magnetospheric oxygen population. [less ▲]

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See detailThe energetic state of mitochondria modulates complex III biogenesis through the ATP-dependent activity of Bcs1.
Ostojić, Jelena; Panozzo; Lasserre, JP et al

in Cell Metabolism (2013), 18/4

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See detailEnergetic study of solar-like oscillations in red giants
Grosjean, Mathieu ULiege

Doctoral thesis (2015)

Observations of solar-like oscillations by CoRoT and Kepler space-borne telescopes, have opened new opportunities for the energetic modelling of these oscillations. In particular, oscillations propagating ... [more ▼]

Observations of solar-like oscillations by CoRoT and Kepler space-borne telescopes, have opened new opportunities for the energetic modelling of these oscillations. In particular, oscillations propagating in both the convective envelope and the radiative core of evolved low-mass stars, called mixed-modes, have been detected, allowing us to investigate various physical processes acting on oscillations in these two regions. Theoretical predictions for the linewidths and the amplitudes of solar-like oscillations, as obtained and discussed in this thesis, strongly depend on the treatment of the interaction between convection and oscillations. Observed properties of solar-like oscillations thus gives us the opportunity to test and constrain this treatment. The comparisons between observed and theoretical linewidths of main-sequence stars allow us to constrain the parameters of the time-dependent treatment of convection and to produce more accurate results. The remaining discrepancies will give us new clues for the improvement of the treatment of the interaction between convection and oscillations. The modelling of the energetic aspects of solar-like oscillations in red giants allows us to derive a detectability limit for mixed-modes. These results are in overall good agreement with typical red-giant observed power spectra. A detailed comparison between an observed subgiant and the corresponding theoretical predic- tions confirms that the main aspects of the observed energetic properties of solar-like oscillations are well reproduced by the theoretical modelling. Discrepancies between observed and theoret- ical linewidths of quadrupole mixed-modes lead us to invoke the existence of a new damping mechanism in the core of this star. [less ▲]

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See detailEnergetic systems evaluation using Life Cycle Assessment
Belboom, Sandra ULiege; Léonard, Angélique ULiege

Scientific conference (2012, February 08)

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See detailEnergetical aspects of solar-like oscillations in red giants
Grosjean, Mathieu ULiege; Dupret, Marc-Antoine ULiege

Conference (2013, August 23)

CoRoT and Kepler observations of red giants reveal a large variety of spectra of non- radial solar- like oscillations. Up to now we understood pretty well the frequency patterns for the different global ... [more ▼]

CoRoT and Kepler observations of red giants reveal a large variety of spectra of non- radial solar- like oscillations. Up to now we understood pretty well the frequency patterns for the different global properties or different evolutionary stages of the stars. Here we are interested in the theoretical predictions for the two other components of a power spectra (the linewitdths and the heights). The study of energetic aspects of these oscillations is of great importance to predict the peak parameters in the power spectrum. I will discuss under which circumstances mixed modes are detectable for a large variety of red-giant stellar models, with emphasis on the effect of the evolutionary status of the star along the red-giant branch, for a wide range of stellar masses (from 1 to 2M⊙ ) on theoretical power spectra. [less ▲]

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See detailEnergetical aspects of solar-like oscillations in red giants
Grosjean, Mathieu ULiege; Dupret, Marc-Antoine ULiege; Belkacem, Kevin et al

Conference (2013, December)

CoRoT and Kepler observations of red giants reveal very rich spectra of non-radial solar- like oscillations allowing us to probe their internal structure. The study of energetic aspects of these ... [more ▼]

CoRoT and Kepler observations of red giants reveal very rich spectra of non-radial solar- like oscillations allowing us to probe their internal structure. The study of energetic aspects of these oscillations is of great importance to predict the peak parameters in the power spectrum. The theoretical determination of lifetimes (or equivalently width) of the modes require non- adiabatic computations. Next, combined with a stochastic excitation model, we can also predict the height of the mode and finally obtain theoretical power spectra. Comparison between our theoretical predictions with observations give important constraint on red-giants models. Lifetimes and amplitudes of modes trapped in the envelope (e.g. radial modes) constrain the characteristics of the convective envelope and its time-dependent interaction with oscillations. Lifetimes of mixed-modes (mainly dipolar modes) strongly depend on mode trapping, allowing us to probe the core of red-giants. I will discuss under which circumstances mixed modes are detectable for a large variety of red-giant stellar models, with emphasis on the effect of the evolutionary status of the star (along the red-giant branch and during the He-burning phase) for a wide range of stellar masses (from 0.7 to 4 Msun ) on theoretical power spectra. [less ▲]

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See detailEnergetical aspects of solar-like oscillations in red giants
Grosjean, Mathieu ULiege; Dupret, Marc-Antoine ULiege; Belkacem, Kevin et al

in Precision Asteroseismology, Proceedings of the International Astronomical Union, IAU Symposium, Volume 301 (2014)

Detailed reference viewed: 18 (1 ULiège)