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See detailLiteraturwissenschaft als Kulturwissenschaft
Pontzen, Alexandra ULg

in Literaturkritik.de (2005)

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See detailLithiase rénale et urétérale: quand et comment intervenir ?
Hamaide, Annick ULg; Dunn, Marylin

Conference (2014)

Detailed reference viewed: 9 (2 ULg)
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See detailLithiase urinaire : analyse morpho-constitutionnelle, épidémiologie, lien avec la vitamine D
Castiglione, Vincent ULg

Scientific conference (2015, February 12)

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See detailLithiation of toluene by organolithium compounds activated by lithium polyether alkoxides
Nugay, Nihan; Nugay, Turgut; Jérôme, Robert ULg et al

in Journal of Molecular Catalysis A: Chemical (2002), 179(1-2), 59-64

The catalytic effect of polyether alkoxides (PEAs) on the activity of organolithium. compounds as metallating agent has been investigated. Toluene has been lithiated by using different organolithiums ... [more ▼]

The catalytic effect of polyether alkoxides (PEAs) on the activity of organolithium. compounds as metallating agent has been investigated. Toluene has been lithiated by using different organolithiums activated by various PEAs. It has been found that n-BuLi, yields higher conversion with 100% benzylic position metallation, whereas sec-BuLi gives some metallation at ring positions with the most reactive ligand, lithium 2-methoxy ethoxide (LiOEM). Optimum PEA to organolithium molar ratio for both sec- and n-BuLi activated by LiOEM where the amount of toluene being kept constant, was found to be as 3:1 with highest yield and regioselectivity. Substantial increment in yield was observed when the amount of substrate increased whereas regioselectivity stayed almost constant. It was also found that, for a constant reactant molar ratio (3:1:15) for which the optimum results were achieved, reaction began early and then yield values increased with time whereas upon increase in reaction temperature from -78 to 20degreesC, the benzylic metallation yield increased drastically while keeping the same regioselectivity high. [less ▲]

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See detailLithic industries as chronological data: the example of Grotte du Renne VII
Dinnis, Rob; Flas, Damien ULg

Conference (2013)

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See detailLithic Management in the Chassey Culture Neolithic
Gassin, Bernard; Léa, Vanessa; Astruc, Laurence et al

in Human Evolution (2010), 25

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See detailLithic Resource Management during the Belgian Early Upper Paleolithic: Effects of Variable Raw Material Context on Lithic Economy
Miller, Rebecca ULg

Book published by Centre de Recherches Archéologiques (2001)

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See detailLithics in Belgium. Some Current Research Trends
Rots, Veerle ULg; Vermeersch, Pierre

in Lithic Technology (2000), 25(2), 76-79

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See detailLithium diisopropylamide as initiator for the anionic polymerization of methacrylates
Antoun, Sayed; Teyssié, Philippe; Jérôme, Robert ULg

in Macromolecules (1997), 30(6), 1556-1561

The anionic polymerization of a series of methacrylates, i.e. methyl methacrylate (MMA), tert-butyl methacrylate (tBuMA), (dimethylamino)ethyl methacrylate (DMAEMA), and glycidyl methacrylate (GMA), has ... [more ▼]

The anionic polymerization of a series of methacrylates, i.e. methyl methacrylate (MMA), tert-butyl methacrylate (tBuMA), (dimethylamino)ethyl methacrylate (DMAEMA), and glycidyl methacrylate (GMA), has been investigated in THF at −78 °C, by using both lithium diisopropylamide (LDA) and α-lithioethyl isobutyrate (Li-EIB) complexed with LiCl as initiators. Compared to ligated Li-EIB, which is a model for the propagating enolate in the methacrylate anionic polymerization, ligated LDA has quite a comparable initiation efficiency (>90%) and gives rise to polymers with a predictable molecular weight and a narrow molecular weight distribution (MWD < 1.1). The effect of LiCl on the MWD of poly-GMA is less pronounced compared to the other polymethacrylates. An already narrow MWD in the absence of LiCl might be accounted for by an intramolecular coordination of the ion pair by the oxirane group of the (ante)penultimate unit(s) of growing poly GMA. As a direct consequence of the well-controlled anionic polymerization of these methacrylates, pairs of them have been polymerized in a sequential way with formation of well-defined block copolymers. Actually, there is no restriction on the addition order of the comonomers, so that both types of triblocks (ABA and BAB) can be successfully synthesized. Size exclusion chromatography supports that block copolymers are not contaminated by homopolymers, at least in detectable amounts. [less ▲]

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See detailLithium transition metal (Ti, Nb, V) oxide mesoporous thin films: contrasting results when attempting direct synthesis by evaporation-induced self assembly
Caes, Sébastien ULg; Malherbe, Cédric ULg; Krins, Natacha ULg et al

in Microporous and Mesoporous Materials (2013), 172

This work investigates the possibility to prepare mesoporous thin films of Li-Ti, Li-Nb, Li-Nb-V and Li-V oxides through a direct sol-gel EISA route by dissolving a lithium salt in the precursor solution ... [more ▼]

This work investigates the possibility to prepare mesoporous thin films of Li-Ti, Li-Nb, Li-Nb-V and Li-V oxides through a direct sol-gel EISA route by dissolving a lithium salt in the precursor solution. Experimental conditions involve a hydrolysis molar ratio H2O/TM ~10 (TM = Ti,Nb,V) and the common Pluronic structuring agent P123 (EO20-PO70-EO20). Systematic formation of lithium-containing oxides as first-crystallizing phases points to a significant intermixture of lithium and transition metal ions in the inorganic network. In the case of Ti-based and Nb-based oxide films, addition of lithium to the precursor solution is compatible with the formation of amorphous mesoporous films at 350°C. On the contrary, addition of lithium has a detrimental effect on the notoriously difficult formation of vanadium-based mesostructured films: even when replacing half of the vanadium by niobium as a stabilizer, formation of mesostructured films has not been possible in the investigated range of experimental conditions. [less ▲]

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See detailLithogeochemical investigations in the Omolon Region (NE-USSR).
Swennen, R; Bless, M.J.M.; Bouckaert, J et al

in Annales de la Société Géologique de Belgique (1985), 108

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See detailLithographic Manufacturing of Zeroth Order Gratings for Innovative Achromatic IR Phase Shifters - Final Report
Loicq, Jerôme ULg; Lenaerts, Cedric ULg; Fleury-Frenette, Karl ULg et al

Report (2009)

Direct detection and characterization of faint sources around bright astrophysical objects is very difficult due to the large flux ratio between them. For example, an Earth-like exoplanet is typically ... [more ▼]

Direct detection and characterization of faint sources around bright astrophysical objects is very difficult due to the large flux ratio between them. For example, an Earth-like exoplanet is typically about 1010 times fainter than its host star in the visible spectrum, reducing to about 107 in the thermal infrared. Infrared nulling interferometry proposed by Bracewell, in 1978, appears to be one of the most promising techniques to achieve the high angular resolution and high dynamic range required to allow the ambitious detection of the first exobiological tracers on extrasolar Earth-like planets, if they exist. The nulling interferometry technique consists in adjusting the phases of the beams coming from various telescopes (two in the most simple configuration) to produce a fully destructive interference on the optical axis. The quality of the destructive interference or the so-called null depth (N) relies on the optical component ability to induce a very precise phase shift (e.g. π radians for a two-telescope configuration) and a very low amplitude mismatch over the considered wavelength range. Unfortunately, searching for biomarkers in exoplanet atmospheres requires spectroscopic characterization over large spectral bands. For example, the Darwin infrared space interferometer considered by ESA will operate in a wavelength band between 6 and 18 μm, seeking biosignatures like the O3-H2O-CO2 triplet. The huge flux ratio between the parent star and the planet therefore requires unprecedented highperformance broadband achromatic phase shifters (APS). The performance requirement for the APS components directly comes from the 10-7 planet-star contrast but also from the system architecture and the associate amount of residual stellar leakage. [less ▲]

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See detailLes lithométéores au Niger: mise au point.
Ozer, Pierre ULg

in Würzburger Geographische Arbeiten (2002), (97), 7-32

Detailed reference viewed: 51 (1 ULg)
See detailLithometeors and wind velocity in relation with desertification during the dry season from 1951 to 1994 in Niger
Ozer, Pierre ULg

in DEMAREE, Gaston; Alexandre, Jean; DE DAPPER, Morgan (Eds.) Tropical climatology, meteorology and hydrology : in memoriam Franz Bultot (1924-1995). (1998)

Detailed reference viewed: 16 (2 ULg)
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See detailLithometeors in relation with desertification in the Sahelian area of Niger
Ozer, Pierre ULg

in Fantechi, R.; Peter, D.; Balabanis, P. (Eds.) et al Desertification in a European Context: Physical and socio-economic aspects (1995)

Detailed reference viewed: 23 (0 ULg)