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See detailThe CN isotopic ratios in comets
Manfroid, Jean ULg; Jehin, Emmanuel ULg; Hutsemekers, Damien ULg et al

in Astronomy and Astrophysics (2009), 503

Our aim is to determine the isotopic ratios [SUP]12[/SUP]C/[SUP]13[/SUP]C and [SUP]14[/SUP]N/[SUP]15[/SUP]N in a variety of comets and link these measurements to the formation and evolution of the solar ... [more ▼]

Our aim is to determine the isotopic ratios [SUP]12[/SUP]C/[SUP]13[/SUP]C and [SUP]14[/SUP]N/[SUP]15[/SUP]N in a variety of comets and link these measurements to the formation and evolution of the solar system. The [SUP]12[/SUP]C/[SUP]13[/SUP]C and [SUP]14[/SUP]N/[SUP]15[/SUP]N isotopic ratios are measured for the CN radical by means of high-resolution optical spectra of the R branch of the B-X (0, 0) violet band. 23 comets from different dynamical classes have been observed, sometimes at various heliocentric and nucleocentric distances, in order to estimate possible variations of the isotopic ratios in parent molecules. The [SUP]12[/SUP]C/[SUP]13[/SUP]C and [SUP]14[/SUP]N/[SUP]15[/SUP]N isotopic ratios in CN are remarkably constant (average values of, respectively, 91.0 ± 3.6 and 147.8 ± 5.7) within our measurement errors, for all comets whatever their origin or heliocentric distance. While the carbon isotopic ratio does agree with the terrestrial value (89), the nitrogen ratio is a factor of two lower than the terrestrial value (272), indicating a fractionation in the early solar system, or in the protosolar nebula, common to all the comets of our sample. This points towards a common origin of the comets independently of their birthplaces, and a relationship between HCN and CN. Appendices and Table [see full textsee full textsee full text] are only available in electronic form at http://www.aanda.org Based on observations made with ESO Telescopes at the La Silla Paranal Observatory under programmes ID 268.C-5570, 270.C-5043, 073.C-0525, 274.C-5015 and 075.C-0355(A). [less ▲]

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See detailCn. Octavius (cos. 165) dans un nouveau sénatus-consulte découvert à Volos ?
Famerie, Etienne ULg

Scientific conference (2012, April 04)

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See detailCn. Octavius (cos. 165) dans un nouveau sénatus-consulte découvert à Volos ?
Famerie, Etienne ULg

in Chiron. Mitteilungen der Kommission für Alte Geschichte und Epigraphik des Deutschen Archäologischen Instituts (2013), 43

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See detailCNMNC guidelines for the use of suffixes and prefixes in mineral nomenclature, and for the preservation of historical names.
Hatert, Frédéric ULg; Mills, Stuart; Pasero, Marco et al

in European Journal of Mineralogy (2013), 25

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See detailCNV and dopamine receptor reactivity: correlations with the apomorphine test.
Timsit-Berthier, Martine; Mantanus, Huguette; Marissiaux, Pascale et al

in McCallum, W. C. (Ed.) Cerebral psychophysiology: studies in event-related potentials. (1986)

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See detailCNV in mood disorders
Papart, Patrick ULg; Ansseau, Marc ULg; Timsit-Berthier, M.

in Recent advances in event-related brain potential research (1996)

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See detailCO emissions of fuel oil boilers in transient and cyclic regimes: performance of burners without and with “antidrip” systems
Makaire, Danielle ULg; Ngendakumana, Philippe ULg

Conference (2007, September)

CO emission peaks from fuel oil boilers in transient and cyclic regimes have been measured in previous studies. In order to evaluate these emissions, tests have been performed without and with an anti ... [more ▼]

CO emission peaks from fuel oil boilers in transient and cyclic regimes have been measured in previous studies. In order to evaluate these emissions, tests have been performed without and with an anti-drip system installed on the burner nozzle. Flue gas composition was measured using classical analysers (CO2, O2, CO and NOx) and CO emissions results were analysed and discussed. It was found that the anti-drip system reduced cold start CO emissions and did not affect steady-state CO emissions. At first, no reduction was noticed when the burner was cycling. Further investigation indicated that there was an experimental artefact caused by an air volume trapped in the pressure measurement system. When the air was purged and with the anti-drip system, CO peaks when the burner was cycling were strongly reduced and CO emissions remained under European standards limits. [less ▲]

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See detailCO emissions of fuel oil boilers used in domestic heating
Cuevas, Cristian; Ngendakumana, Philippe ULg

Conference (2006, August)

To assess the CO emissions of fuel oil boilers, tests have been performed on a boiler in transient and steady state regimes. The tests were performed so that the output power (about 370 kW) was kept ... [more ▼]

To assess the CO emissions of fuel oil boilers, tests have been performed on a boiler in transient and steady state regimes. The tests were performed so that the output power (about 370 kW) was kept constant in steady state regime (same water flow rate and inlet and outlet temperatures). On the other hand, the oxygen content of the flue gas in the chimney was kept constant (around 3%). Classical gas analysers were used to measure the CO2, O2, CO and NOx concentrations in the flue gas. The two main parameters investigated are the nozzle capacity and the corresponding fuel injection pressure to keep the same burner consumption. Four nozzles whose capacity ranges from 30 to 45 kg/h (at a fuel supply pressure of 20 bar) were fitted on the burner equipping the fuel oil boiler. All the nozzles used are spill return and 45° spray angle type. The tests performed showed that in steady-state regime, the CO emissions are very low compared to the limits established by the European standard (110 mg/kWh of energy consumption). A comparison with calculated CO emissions shows also that the values obtained in equilibrium conditions are too high. On the other hand, in the transient regime (start-up regime for a cycling boiler), the CO emissions are not negligible and increase significantly if a high capacity nozzle is fitted on the fuel oil burner. In short, the paper demonstrates that in order to increase the boiler thermal efficiency and thus to reduce CO2 emissions (for the same output power), one has to avoid the CO emissions in the transient regime. When performing a replacement of the burner nozzle, a low capacity nozzle associated with an adjustment of a high fuel injection pressure is recommended, since a reduction of CO emissions in the starting-up regime is achieved and, on the other hand, the thermal efficiency and the pollutants emissions of the fuel oil boiler in steady state regime are not affected. [less ▲]

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See detailCO Gas Inside the Protoplanetary Disk Cavity in HD 142527: Disk Structure from ALMA
Perez, S.; Casassus, S.; Ménard, F. et al

in Astrophysical Journal (2014), 798

Inner cavities and annular gaps in circumstellar disks are possible signposts of giant planet formation. The young star HD 142527 hosts a massive protoplanetary disk with a large cavity that extends up to ... [more ▼]

Inner cavities and annular gaps in circumstellar disks are possible signposts of giant planet formation. The young star HD 142527 hosts a massive protoplanetary disk with a large cavity that extends up to 140 AU from the central star, as seen in continuum images at infrared and millimeter wavelengths. Estimates of the survival of gas inside disk cavities are needed to discriminate between clearing scenarios. We present a spatially and spectrally resolved carbon monoxide isotopologue 2-1 line of $^12$CO, $^13$CO, and C[SUP]18[/SUP]$O obtained with the Atacama Large Millimeter/submillimeter Array (ALMA). We detect emission coming from inside the dust-depleted cavity in all three isotopologues. Based on our analysis of the gas in the dust cavity, the $^12$CO emission is optically thick, while $^13$CO and C[SUP]18[/SUP]$O emissions are both optically thin. The total mass of residual gas inside the cavity is \~1.5-2 M $_Jup$. We model the gas with an axisymmetric disk model. Our best-fit model shows that the cavity radius is much smaller in CO than it is in millimeter continuum and scattered light observations, with a gas cavity that does not extend beyond 105 AU (at 3$\sigma$). The gap wall at its outer edge is diffuse and smooth in the gas distribution, while in dust continuum it is manifestly sharper. The inclination angle, as estimated from the high velocity channel maps is 28 \plusmn 0.5 deg, higher than in previous estimates, assuming a fix central star mass of 2.2 M $_&sun;$. [less ▲]

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See detailCO measurements from the ACE-FTS satellite instrument: data analysis and validation using ground-based, airborne and spaceborne observations
Clerbaux, Catherine; George, Maya; Turquety, Solène et al

in Atmospheric Chemistry and Physics (2008), 8

The Atmospheric Chemistry Experiment (ACE) mission was launched in August 2003 to sound the atmosphere by solar occultation. Carbon monoxide (CO), a good tracer of pollution plumes and atmospheric ... [more ▼]

The Atmospheric Chemistry Experiment (ACE) mission was launched in August 2003 to sound the atmosphere by solar occultation. Carbon monoxide (CO), a good tracer of pollution plumes and atmospheric dynamics, is one of the key species provided by the primary instrument, the ACE-Fourier Transform Spectrometer (ACE-FTS). This instrument performs measurements in both the CO 1-0 and 2-0 ro-vibrational bands, from which vertically resolved CO concentration profiles are retrieved, from the mid-troposphere to the thermosphere. This paper presents an updated description of the ACE-FTS version 2.2 CO data product, along with a comprehensive validation of these profiles using available observations (February 2004 to December 2006). We have compared the CO partial columns with ground-based measurements using Fourier transform infrared spectroscopy and millimeter wave radiometry, and the volume mixing ratio profiles with airborne (both high-altitude balloon flight and airplane) observations. CO satellite observations provided by nadir-looking instruments (MOPITT and TES) as well as limb-viewing remote sensors (MIPAS, SMR and MLS) were also compared with the ACE-FTS CO products. We show that the ACE-FTS measurements provide CO profiles with small retrieval errors (better than 5% from the upper troposphere to 40 km, and better than 10% above). These observations agree well with the correlative measurements, considering the rather loose coincidence criteria in some cases. Based on the validation exercise we assess the following uncertainties to the ACE-FTS measurement data: better than 15% in the upper troposphere (8–12 km), than 30% in the lower stratosphere (12–30 km), and than 25% from 30 to 100 km. [less ▲]

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See detailCO spiral arms in the outer disk of HD 142527 with ALMA
Christiaens, Valentin ULg; Casassus, Simon; Perez, Sebastian et al

Poster (2014)

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See detailCO spiral arms in the outer disk of HD 142527 with ALMA
Christiaens, Valentin ULg; Casassus, Simon; Perez, Sebastian et al

in Iono, Daisuke; Wootten, Al; Testi, Leonardo (Eds.) REVOLUTION IN ASTRONOMY WITH ALMA: THE THIRD YEAR (2014)

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See detail(Co)Polymerization of vinyl levulinate by cobalt-mediated radical polymerization and functionalization by ketoxime click chemistry
Allaoua, Imène; Eleuterio, Beatriz; Obadia, Mona M. et al

in Polymer Chemistry (2014), 5(8), 2973-2979

Vinyl levulinate is synthesized from levulinic acid by palladium-catalyzed vinyl exchange and is characterized by NMR and ESI-HRMS techniques. Homopolymerization of vinyl levulinate and random ... [more ▼]

Vinyl levulinate is synthesized from levulinic acid by palladium-catalyzed vinyl exchange and is characterized by NMR and ESI-HRMS techniques. Homopolymerization of vinyl levulinate and random copolymerization with vinyl acetate by cobalt-mediated radical polymerization affords well-defined ketone functionalized poly(vinyl ester)s. The impact of temperature, solvent and theoretical degree of polymerization on monomer conversion and control of the polymerization is studied by 1H NMR and size exclusion chromatography techniques. The ketoxime conjugation of O-benzylhydroxylamine with the pendant ketone functionality of poly(vinyl levulinate-co-vinyl acetate) is demonstrated. [less ▲]

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See detailCo-construction
Poumay, Marianne ULg

in Glossaire de la diversité culturelle à l’ère du numérique (2014)

Le terme « co-construction » évoque aussi bien le processus que le résultat de l’action de co-construire, c’est-à-dire de construire en collaboration. Il implique la présence de l’autre, sa participation ... [more ▼]

Le terme « co-construction » évoque aussi bien le processus que le résultat de l’action de co-construire, c’est-à-dire de construire en collaboration. Il implique la présence de l’autre, sa participation à un agir dont nous choisirons pour cet article le versant conscient, orienté vers un but d’apprentissage. [less ▲]

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See detailLa co-construction de soi et de ses savoirs professionnels comme effet de l'alternance: quels indicateurs?
Vanhulle, Sabine; Mottier Lopez, Lucie; Deum, Mélanie ULg

in Merhan, France; Ronveaux, Christophe; Vanhulle, Sabine (Eds.) Alternances en formation (2007)

Cette contribution porte sur la construction de savoirs professionnels dans l'alternance en formation initiale à l'enseignement. Elle postule que cette construction de savoirs se relie à l'émergence de l ... [more ▼]

Cette contribution porte sur la construction de savoirs professionnels dans l'alternance en formation initiale à l'enseignement. Elle postule que cette construction de savoirs se relie à l'émergence de l'identité professionnelle: le sujet en formation se construit comme acteur social en même temps des savoirs propices à son agir. Plus précisément, notre préoccupation de recherche concerne les indicateurs de cette co-construction soi/savoirs professionnels tels qu'on peut les inférer à partir de l'analyse de discours écrits ou oraux produits par les étudiants. [less ▲]

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See detailCo-construire des savoirs et se développer mutuellement entre cherchers et praticiens enseignants
Dejean, Karine ULg

in Spirales (2010), 46

Cet article propose une description et une analyse de dispositifs de formation fondés sur une démarche de co-construction de savoirs entre praticiens-enseignants et chercheurs. Ces dispositifs de ... [more ▼]

Cet article propose une description et une analyse de dispositifs de formation fondés sur une démarche de co-construction de savoirs entre praticiens-enseignants et chercheurs. Ces dispositifs de formation s’inscrivent dans une perspective de développement professionnel mutuel des praticiens-enseignants et des chercheurs, chacun des partenaires étant engagé dans un projet commun, la construction de savoirs (Donnay et Charlier, 2001, 2006). Ils sont fondés sur un processus d’enrôlement des acteurs dont nous identifions les différentes étapes et les attitudes qui le soutiennent [less ▲]

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See detailCo-construire la qualité: dispositif et démarche
Pirard, Florence ULg

in Génération ONE (1999), 6

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See detailCo-creating nano-imaginaries: A report of a Delphi-exercise
Deblonde, Marian; Van Oudheusden, Michiel ULg; Evers, Johan et al

in Bulletin of Science, Technology & Society (2008), 28(5), 372-389

Detailed reference viewed: 9 (1 ULg)