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See detailCarbon dioxide, a cheap bio-sourced building block for cyclic carbonates and non-isocyanate polyurethanes
Gennen, Sandro ULg; Alves, Margot ULg; Tassaing, Thierry et al

Poster (2015, May 03)

Due to concerns about global warming combined with the decrease of fossil resources, new carbon feedstocks that are abundant, renewable, non-toxic, inexpensive and environmentally friendly must be ... [more ▼]

Due to concerns about global warming combined with the decrease of fossil resources, new carbon feedstocks that are abundant, renewable, non-toxic, inexpensive and environmentally friendly must be explored to produce chemicals. Besides the valorization of bio-based raw materials, the chemical transformation of carbon dioxide into added-value products has gained interest in both academia and industry. To date, the chemical fixation of CO2 onto epoxides with the formation of cyclic carbonates is one of the most promising ways to valorize CO2 at an industrial scale. Indeed, cyclic carbonates find applications as electrolytes in lithium ion batteries, as aprotic polar solvents or as useful intermediates for polycarbonates. Cyclic carbonates also react with primary amines to produce 2-hydroxyethylurethane. This reaction can be extrapolated to the synthesis of non-isocyanate polyurethanes (NIPU) by polyaddition of bifunctional cyclic carbonates with diamines.5 This study aims (i) at developing a new highly efficient organocatalyst for the synthesis of cyclic carbonates under mild experimental conditions and (ii) their valorization as monomers to produce non-isocyanate polyurethanes. First, we have identified a bicomponent organocatalyst, composed of a judicious combination of an organocatalyst and an activator, for the very fast synthesis of cyclic carbonates from CO2 and epoxides under very mild reaction conditions. Kinetics of reactions were followed by online Raman spectroscopy measurements under pressure. NMR titrations were realized to evidence the mechanism of activation of this novel organocatalytic system that will be discussed in detail in this talk. The second objective relies on the development of new efficient organocatalysts for the synthesis of high molar masses NIPUs in short reaction times. Organic compounds interacting with the cyclic carbonate by hydrogen bonding were identified and their catalytic activity was demonstrated for model compounds. [less ▲]

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See detailMetabolomic analysis of the green microalga Chlamydomonasreinhardtii cultivated under day/night conditions
Willamme, Rémi ULg; Alsafra, Zouheir; Arumugam, Rameshkumar et al

in Journal of Biotechnology (2015)

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See detailControlled synthesis of ethylene-vinyl acetate based copolymers by organometallic mediated radical polymerization
Demarteau, Jérémy ULg; Kermagoret, Anthony ULg; Jérôme, Christine ULg et al

in Matyjaszewski, Krzysztof; Sumerlin, Brent S.; Tsarevsky, Nicolay V. (Eds.) et al Controlled Radical Polymerization: Materials (2015)

The controlled radical copolymerization of ethylene (E) and vinyl acetate (VAc) is further investigated by organometallic- mediated radical polymerization (OMRP) using Co(acac)2 as controlling agent at ... [more ▼]

The controlled radical copolymerization of ethylene (E) and vinyl acetate (VAc) is further investigated by organometallic- mediated radical polymerization (OMRP) using Co(acac)2 as controlling agent at ethylene pressure up to 100 bar. The effect of ethylene pressure on kinetics, level of control and copolymer composition, is discussed. Ethylene-Vinyl Acetate copolymers (EVAs) with low dispersities and ethylene content reaching 57 mol% are notably reported. This work also successfully addresses the precision design of EVA-containing block copolymers, i.e. PVAc-block-EVA. In this case, the order of the synthesis of the blocks is a key parameter. The “PVAc-first” strategy is by far more practical and efficient. [less ▲]

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See detailVariability in the super-Earth 55 Cnc e
Demory, Brice-Olivier; Gillon, Michaël ULg; Madhusudhan, Nikku et al

E-print/Working paper (2015)

Considerable progress has been made in recent years in observations of atmospheric signatures of giant exoplanets, but processes in rocky exoplanets remain largely unknown due to major challenges in ... [more ▼]

Considerable progress has been made in recent years in observations of atmospheric signatures of giant exoplanets, but processes in rocky exoplanets remain largely unknown due to major challenges in observing small planets. Numerous efforts to observe spectra of super-Earths, exoplanets with masses of 1-10 Earth masses, have thus far revealed only featureless spectra. In this paper we report a 4-$\sigma$ detection of variability in the dayside thermal emission from the transiting super-Earth 55 Cancri e. Dedicated space-based monitoring of the planet in the mid-infrared over eight eclipses revealed the thermal emission from its dayside atmosphere varying by a factor 3.7 between 2012 and 2013. The amplitude and trend of the variability are not explained by potential influence of star spots or by local thermal or compositional changes in the atmosphere over the short span of the observations. The possibility of large scale surface activity due to strong tidal interactions possibly similar to Io, or the presence of circumstellar/circumplanetary material appear plausible and motivate future long-term monitoring of the planet. [less ▲]

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See detailPhotometric identification of the periods of the first candidate extragalactic magnetic massive stars
Nazé, Yaël ULg; Walborn, Nolan R.; Morrell, Nidia et al

in Astronomy and Astrophysics (2015), 577

Galactic stars belonging to the Of?p category are all strongly magnetic objects exhibiting rotationally modulated spectral and photometric changes on timescales of weeks to years. Five candidate Of?p ... [more ▼]

Galactic stars belonging to the Of?p category are all strongly magnetic objects exhibiting rotationally modulated spectral and photometric changes on timescales of weeks to years. Five candidate Of?p stars in the Magellanic Clouds have been discovered, notably in the context of ongoing surveys of their massive star populations. Here we describe an investigation of their photometric behaviour, revealing significant variability in all studied objects on timescales of one week to more than four years, including clearly periodic variations for three of them. Their spectral characteristics along with these photometric changes provide further support for the hypothesis that these are strongly magnetized O stars, analogous to the Of?p stars in the Galaxy. [less ▲]

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See detailInfluence of bottom currents on the sedimentary processes at the western tip of the Gulf of Corinth, Greece
Beckers, Arnaud ULg; Beck, Christian; Hubert, Aurelia ULg et al

in Marine Geology (2015)

We investigated the sedimentary processes that were active during the Holocene in the Gulf of Corinth, using high-resolution seismic reflection profiles and gravity cores. Seismic reflection data clearly ... [more ▼]

We investigated the sedimentary processes that were active during the Holocene in the Gulf of Corinth, using high-resolution seismic reflection profiles and gravity cores. Seismic reflection data clearly show the presence of shallow-water sediment drifts at the western end of the Gulf, close to the Rion Sill that links the gulf to the Ionian Sea. Short cores indicate that drifts are composed of homogenous bioturbated mud in their upper part. The drift deposits flank a wide central area where the sea floor is eroded and where pre-Holocene deposits locally outcrop. The sea floor morphology in this area is marked by furrows oriented in different directions and by a depression attributed to the action of bottom-currents. The magnetic fabric of sediment samples from the drift, shelves, sub-basins and from the basin floor show a significant anisotropy and a similar orientation of Kmax axes along core. The largest anisotropy (P = 1.043 ± 0.007) is observed in the drift and is interpreted as resulting from the action of bottom currents. The similar orientation of Kmax axes in the other cores, collected from areas East of the drifts, suggests that bottom currents also affect sediment deposition in the rest of the study area, even if seismic profiles and core analyses demonstrate that gravitational processes such as submarine landslides and turbidity currents exert the main control on sediment transport and deposition. Average Kmax axes for four cores were reoriented using the declination of the characteristic remanent magnetization. Kmax axes show variable orientations relatively to the slope of the sea floor, between along-slope and roughly parallel to the contour lines. [less ▲]

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See detailLearning from blind tests: residues on grinding stones and flaked stone tools
Rots, Veerle ULg; Hayes, Elspeth; Cnuts, Dries ULg et al

Conference (2015, May)

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See detailStone tool use and hominin evolution
Fullagar, Richard; Rots, Veerle ULg

Conference (2015, May)

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See detailExpression of sexual ornaments in a polymorphic species: phenotypic variation in response to environmental risk
Winandy, Laurane ULg; Denoël, Mathieu ULg

in Journal of Evolutionary Biology (2015), 28(5), 1049-1056

Secondary sexual traits may evolve under the antagonistic context of sexual and natural selection. In some polymorphic species, these traits are only expressed during the breeding period and are ... [more ▼]

Secondary sexual traits may evolve under the antagonistic context of sexual and natural selection. In some polymorphic species, these traits are only expressed during the breeding period and are differently expressed in alternative phenotypes. However, it is unknown whether such phenotypes exhibit phenotypic plasticity of seasonal ornamentations in response to environmental pressures such as in the presence of fish (predation risk). This is an important question to understand the evolution of polyphenisms. We used facultative paedomorphosis in newts as a model system because it involves the coexistence of paedomorphs that retain gills in the adult stage with metamorphs that have undergone metamorphosis, but also because newts exhibit seasonal sexual traits. Our aim was therefore to determine the influence of fish on the development of seasonal ornamentation in the two phenotypes of the palmate newt (Lissotriton helveticus). During the entire newt breeding period, we assessed the importance of phenotype and fish presence with an information-theoretic approach. Our results showed that paedomorphs presented much less developed ornamentation than metamorphs and those ornamentations varied over time. Fish inhibited the development of sexual traits but differently between phenotypes: in contrast to metamorphs, paedomorphs lack the phenotypic plasticity of sexual traits to environmental risk. This study points out that internal and external parameters act in complex ways in the expression of seasonal sexual ornamentations and that similar environmental pressure can induce a contrasted evolution in alternative phenotypes. [less ▲]

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See detailSearching for early traces of fire production on flint tools
Sorensen, Andrew; Rots, Veerle ULg

Conference (2015, May)

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See detailThe stadium of Olympia: a dialogical composition
Kiuri, Miranda; Teller, Jacques ULg

in Montanola, J (Ed.) International Journal Arquitectonics: Architecture, phenomenology & social dialogics (2015)

The article proposes a renewed interpretation of the relation of the antique stadium of Olympia with its built environment. It is argued that the stadium, far from being isolated from the city as commonly ... [more ▼]

The article proposes a renewed interpretation of the relation of the antique stadium of Olympia with its built environment. It is argued that the stadium, far from being isolated from the city as commonly considered, was connected to the Altis through a series of visual relations, adopting principles of dialogical architecture: composition, significant location, functional routes, perceptions, role of architectonic elements and spatial characteristics. This argument is illustrated through computer-generated perspectives of the stadium. [less ▲]

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See detailBeam to concrete-filled rectangular hollow section column joints using long bolts
Hoang, Van Long ULg; Demonceau, Jean-François ULg; Jaspart, Jean-Pierre ULg

in Proceedings of the 15th international symposium on tubular structures - ISTS15 (2015, May)

This paper presents a research on a specific type of unstiffened extended end-plate joint used to connect I-shaped beams to concrete-filled rectangular hollow section columns. The main idea is to use long ... [more ▼]

This paper presents a research on a specific type of unstiffened extended end-plate joint used to connect I-shaped beams to concrete-filled rectangular hollow section columns. The main idea is to use long bolts throughout the column to connect the beam end-plates, so avoiding intermediate connecting elements (e.g. a reverse U channel) or special bolts (e.g. blind bolts). However, the use of long bolts for beam-to-column connections is still rare in the construction and no design procedure exists in the Eurocodes; this justifies the pre-sent research. Firstly, a test program within a RFCS European project titled HSS-SERF “High Strength Steel in Seismic Resistant Building Frames”, 2009-2013 was performed. In this project, specimens subjected to sig-nificant bending moments (and shear) or to shear only was defined. Then, analytical developments based on the component approach and aimed at predicting the joint response have been carried out; their validity is demonstrated through comparisons with the tests. Finally, design guidelines have been provided. [less ▲]

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See detailAdolescent delinquent behaviours as attempts of group social integration and well-being through social acceptance?
Born, Michel ULg; Cattelino, Elena; Gavray, Claire ULg et al

in Carneiro, Roberto; Carneiro, Maria Ana (Eds.) Youth, Offense and Well-Being . Can Science Enlighten Policy? (2015)

Large surveys in Western countries give pictures of adolescent well-being related to delinquency and group affiliation. The belonging to a particular country, city or neighbourhood with their social ... [more ▼]

Large surveys in Western countries give pictures of adolescent well-being related to delinquency and group affiliation. The belonging to a particular country, city or neighbourhood with their social structure influences the probability to have delinquent activities in group increasing or decreasing the risk of marginalisation, the sensibility to deviant values and the well-being related to peers’ acceptance. A general process would exist by which, firstly adolescents oppose themselves to the parents’ authority and seek for acceptance among their peers. This leads to a spiral when the youth tries to resolve his cognitive dissonance between the immoral acts he is invited to commit with his friends and his personal value system learned in his family, school and other institutions. In adolescence, the influence of peers can be positive or negative; it can be “protective peer-contagion” with positive response to normative talk or “deviant peer-contagion” with positive response to deviant talk or behaviour. At the micro level, well-adjusted peers are able to resist the influence of deviant peers. The participation to non-homogenous mixed groups seems to facilitate more normative talks. This leads to the hypothesis that the progressive extension to differentiated groups when adolescence is going through will strengthen their ties with conventional norms and contribute to their well-being. [less ▲]

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See detailHigh output [18F]FDOPA on AllInOne (Trasis) at commercial scale
Otabashi, Muhammad; Cascione, Christian; Lemaire, Christian ULg et al

in Journal of Labelled Compounds & Radiopharmaceuticals (2015, May), 58

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See detailLes attitudes communautaires et le vote
Deschouwer, Kris; De Winter, Lieven; Reuchamps, Min et al

in Deschouwer, Kris; Delwit, Pascal; Hooghe, Marc (Eds.) et al Décrypter l’électeur: Le comportement électoral et les motivations de vote (2015)

Les électeurs en Belgique se sentent-ils Belges, Flamands ou Wallons ? C’est la question principale posée dans le neuvième chapitre écrit par Kris Deschouwer, Lieven de Winter, Min Reuchamps, Dave ... [more ▼]

Les électeurs en Belgique se sentent-ils Belges, Flamands ou Wallons ? C’est la question principale posée dans le neuvième chapitre écrit par Kris Deschouwer, Lieven de Winter, Min Reuchamps, Dave Sinardet et Jérémy Dodeigne. Dans leur conclusion, ils constatent que les identités flamandes et wallonnes sont moins affirmées que l’identité belge, même dans le cas d’une forte polarisation politique autour de la réforme de l’État. En mai 2014, l’enjeu de la réforme de l’État a été – comme par le passé – peu déterminant dans le comportement de vote, même si cela varie d’un électorat de parti à un autre. En Wallonie, cela n’a pas été aussi déterminant, alors qu’en Flandre trois groupes d’électeurs peuvent être discernés. Dans le premier groupe, les partisans d’une plus grande réforme de l’État et d’une plus grande autonomie se retrouvent dans l’électorat de la N-VA et du Vlaams Belang. Dans un groupe plus modéré se retrouvent les électeurs du CD&V, alors que le troisième groupe (le moins favorable à plus de réformes et plus d’autonomie) est constitué des électeurs de l’Open VLD, du sp.a, de Groen et du PvdA. [less ▲]

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See detailRadar remote sensing observations to monitor landslides and prepare inventories for hazard assessment
Schlögel, Romy; Havenith, Hans-Balder ULg; Malet, Jean-Philippe et al

Scientific conference (2015, May)

Abstract: The creation of a landslide inventory encompassing multi-temporal information needs high quality and high-resolution data source as well as a good knowledge of the field. Visual image ... [more ▼]

Abstract: The creation of a landslide inventory encompassing multi-temporal information needs high quality and high-resolution data source as well as a good knowledge of the field. Visual image interpretation and field surveys are the prevailing methods for landslide inventory mapping while remote sensing techniques have become a widely used source of information for measuring the topography and deformation of the Earth surface (e.g. Berardino et al., 2002). Semi-automatic image analysis methods based on remote sensing techniques are proposed but their quality lacks behind the expert mappings (Guzzetti et al., 2012). Advance processing of SAR images have proven their ability for: (1) landslide detection and mapping (Farina et al., 2006; Cascini et al., 2009; Guzzetti et al., 2012), (2) process monitoring (Hilley et al., 2004; Zhao et al., 2012), (3) hazard assessment (e.g. Nikolaeva et al., 2014) and (4) risk management (Bardi et al., 2014). ... [less ▲]

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