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See detailIn situ FTIR micro-spectroscopy to investigate polymeric fibers under supercritical carbon dioxide: CO2 sorption and swelling measurements
Champeau, Mathilde; Thomassin, Jean-Michel ULg; Jérôme, Christine ULg et al

in Journal of Supercritical Fluids (2014), 90

An original experimental set-up combining a FTIR (Fourier Transformed InfraRed) microscope with a high pressure cell has been built in order to analyze in situ and simultaneously the CO2 sorption and the ... [more ▼]

An original experimental set-up combining a FTIR (Fourier Transformed InfraRed) microscope with a high pressure cell has been built in order to analyze in situ and simultaneously the CO2 sorption and the polymer swelling of microscopic polymer samples, such as fibers, subjected to supercritical carbon dioxide. Thanks to this experimental set-up, we have determined as a function of the CO2 pressure (from 2 to 15 MPa) the CO2 sorption and the polymer swelling at T = 40 °C of four polymer samples, namely PEO (polyethylene oxide), PLLA (poly-l-lactide acid), PET (polyethylene terephtalate) and PP (polypropylene). The quantity of CO2 sorbed in all the studied polymers increases with pressure. PEO and PLLA display a significant level of CO2 sorption (20 and 25% respectively, at P = 15 MPa). However, we observe that a lower quantity of CO2 can be sorbed into PP and PET (7 and 8% respectively, at P = 15 MPa). Comparing their thermodynamic behaviors and their intrinsic properties, we emphasize that a high CO2 sorption can be reach if on one hand, the polymer is able to form specific interaction with CO2 in order to thermodynamically favor the presence of CO2 molecules inside the polymer and on the other, displays high chains mobility in the amorphous region. PLLA and PEO fulfilled these two requirements whereas only one property is fulfilled by PET (specific interaction with CO2) and PP (high chains mobility). Finally, we have found that for a given CO2 sorption, the resulting swelling of the polymer depends mainly on its crystallinity. [less ▲]

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See detailThe in situ Glyptostroboxylon forest of Hoegaarden (Belgium) at the Initial Eocene Thermal Maximum (55 Ma)
Fairon-Demaret, Muriel ULg; Steurbaut, Etienne; Damblon, Freddy ULg et al

in Review of Palaeobotany and Palynology (2003), 126(1-2), 103-129

Hundreds of silicified standing stumps have been discovered within a lignitic horizon in the middle of the Tienen Formation near Hoegaarden in northeast Belgium. The anatomical features of the fossil ... [more ▼]

Hundreds of silicified standing stumps have been discovered within a lignitic horizon in the middle of the Tienen Formation near Hoegaarden in northeast Belgium. The anatomical features of the fossil stumps, as those of the numerous silicified secondary xylem remains collected since the last century from this area, demonstrate that they all belong to a single taxodiaceous taxon. The stumps bear characteristics shared by Taxodioxylon gypsaceum and Glyptostroboxylon tenerum, but affinities with the latter appear closer. They are attributed to Glyptostroboxylon sp. Calibration of the sedimentological, stratigraphical and organic carbon isotope data reveals that these taxodiaceous fossil trees developed in a swampy lowland environment most probably during the Initial Eocene Thermal Maximum at ca. 55 Ma. (C) 2003 Elsevier B.V. All rights reserved. [less ▲]

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See detailIn situ hybridization at the electron microscope level: an improved method for precise localization of ribosomal DNA and RNA.
Thiry, Marc ULg; Thiry-Blaise, L.

in European Journal of Cell Biology (1989), 50(1), 235-43

In situ hybridization using biotinylated rDNA probes and secondary antibody coupled to gold particles was developed on ultrathin sections of Lowicryl-embedded Ehrlich tumor cells for precise localization ... [more ▼]

In situ hybridization using biotinylated rDNA probes and secondary antibody coupled to gold particles was developed on ultrathin sections of Lowicryl-embedded Ehrlich tumor cells for precise localization of ribosomal RNA (rRNA) and ribosomal DNA (rDNA). For the detection of rDNA, an immunocytochemical approach involving an antibody against single-stranded DNA was used in order to determine the more efficient denaturation procedure. Using this technique, rDNA can be visualized in the fibrillar centers of nucleoli, especially in their peripheral regions at the proximity of both the dense fibrils and the nucleolar interstices as well as within the latter. rDNA was occasionally detected in some clumps of dense nucleolus-associated chromatin. Besides the presence of rRNA in the ribosome-rich cytoplasmic areas and in the dense fibrillar component and the granular component of the nucleolus, rRNA was also found in the fibrillar center areas close to the boundary region to the dense fibrillar component. These results are discussed in the light of the present knowledge on the functional organization of the nucleolus. [less ▲]

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See detailIn Situ Lipidomic Analysis of Nonalcoholic Fatty Liver by Cluster TOF-SIMS Imaging
Debois, Delphine ULg; Bralet, Marie-Pierre; Le Naour, François et al

in Analytical Chemistry (2009), 81(8), 2823-2831

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See detailIn situ localisation and quantification of surfactins in a Bacillus subtilis swarming community by imaging mass spectrometry
Debois, Delphine ULg; Hamzé, Kassem; Guérineau, Vincent et al

in Proteomics (2008), 8(18), 3682-3691

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See detailIN SITU MEASUREMENTS OF METAZOOPLANKTON PREDATION ON PROTOZOOPLANKTON: USE OF FLUORESCENTLY LABELLED PROTISTS.
Joaquim-Justo, Célia ULg; Caufman, F; Thomé, Jean-Pierre ULg

Poster (2001, February 04)

The importance of trophic relationships between metazooplankton and protozoans in rivers are not yet well known, but as some authors have shown during the last decade, the predation exerted by ... [more ▼]

The importance of trophic relationships between metazooplankton and protozoans in rivers are not yet well known, but as some authors have shown during the last decade, the predation exerted by metazooplankton on these organisms might be of importance in the transfer of energy from the pico- and nanoplankton to the metazooplankton. Fluorescent carboxylate microspheres of 0.5 µm in diameter were used to label natural protozooplankton. Different combinations of labelling times and concentrations of microspheres were tested to achieve an optimal labelling of the protists (i.e. a maximal proportion of individuals labelled with an identical number of microspheres); the most appropriate labelling conditions were with short incubations (10 minutes) and relatively low microsphere concentrations (1.105 FMP/ml). Live labelled protozooplankton was used to determine ingestion rates of the natural metazooplankton of the river Meuse (Belgium). It could be showed for all abundant species (i.e. the rotifers Brachionus calyciflorus, Brachionus angularis and Keratella cochlearis) that the predation exerted on protozooplankton was high (from 34 to 182 protists.rotifer-1.h-1) in in situ conditions. [less ▲]

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See detailIn situ measurements of the nitrogen assimilation by marine plants using 15N (Gulf of Calvi-Corsica)
Millet, Sylvie; Nyssen, Fabienne; Lepoint, Gilles ULg et al

Poster (1997, September)

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See detailIn situ measurements of the static liquid holdup in Katapak-SP12 (TM) packed column using X-ray tomography
Aferka, Saïd ULg; Crine, Michel ULg; Saroha, A. K. et al

in Chemical Engineering Science (2007), 62(21), 6076-6080

Static liquid holdup was determined in situ, in a column packed with Katapak-SP12 (TM) elements, using a non-intrusive X-ray tomographic technique. Experiments were performed in a 10 cm diameter PVC ... [more ▼]

Static liquid holdup was determined in situ, in a column packed with Katapak-SP12 (TM) elements, using a non-intrusive X-ray tomographic technique. Experiments were performed in a 10 cm diameter PVC column with the air-water system. The technique allows a local determination of the various liquid holdup as well as of the capillary height, without dismantling the elements. Results are in good agreement with correlations proposed in the literature. (C) 2007 Elsevier Ltd. All rights reserved. [less ▲]

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See detailIn situ nick translation at the electron microscopic level
Thiry, Marc ULg

in Didenko, V V (Ed.) Methods in molecular biology. In situ detection of DNA damage: methods and protocols (2002)

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See detailIn situ nick translation at the electron microscopic level: a tool for studying the location of DNAse I-sensitive regions within the cell.
Thiry, Marc ULg

in Journal of Histochemistry and Cytochemistry : Official Journal of the Histochemistry Society (1991), 39(6), 871-4

The in situ nick translation method was adapted to the ultrastructural level, to study the location of DNAse I-sensitive sequences within the cell. Ultra-thin sections of Lowicryl-embedded cells were ... [more ▼]

The in situ nick translation method was adapted to the ultrastructural level, to study the location of DNAse I-sensitive sequences within the cell. Ultra-thin sections of Lowicryl-embedded cells were incubated in a medium containing DNAse I, DNA polymerase I, and all four deoxyribonucleotides, some being biotinylated. The nick-translated sites were then visualized by an indirect immunogold labeling technique. The resulting labeling pattern is closely dependent on the DNAse I concentration in the nick-translation medium. The method reveals with great precision the specific DNAse I-sensitive regions within the nucleus. This technique can be used to discriminate between active and inactive regions of interphase chromatin. [less ▲]

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See detailIn situ nitroxide-mediated polymerization of styrene promoted by the N-tert-butyl-alpha-isopropylnitrone/BPO pair: ESR investigations
Detrembleur, Christophe ULg; Clément, Jean-Louis; Sciannaméa, Valérie et al

in Journal of Polymer Science. Part A, Polymer Chemistry (2013), 51(8), 1786-1795

The styrene polymerization initiated by benzoyl peroxide (BPO) in the presence of N-tert-butyl--isopropylnitrone as nitroxide precursor is well-controlled provided that a prereaction between the nitrone ... [more ▼]

The styrene polymerization initiated by benzoyl peroxide (BPO) in the presence of N-tert-butyl--isopropylnitrone as nitroxide precursor is well-controlled provided that a prereaction between the nitrone and BPO is carried out in suitable conditions prior to polymerization at a higher temperature. Electron spin resonance (ESR) spectroscopy was implemented to probe the nitroxides formed during both steps, that is, the prereaction and polymerization, and to get crucial information regarding the structure of the nitroxides responsible for the polymerization control. ESR studies combined with first principles calculations have evidenced that nitroxides observed during the prereaction in the presence of styrene and during the polymerization steps consist of a mixture of two macronitroxides. One is formed by the addition of a growing polystyrene chain to the nitrone as would be expected. However, the second one results from the addition of a polystyrene chain to tert-butyl nitroso that is in situ formed presumably by decomposition of the first macronitroxide type. [less ▲]

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See detailAn in situ NMR analysis of the formation of P- and SiO2-doped TiO2 xerogels
Bodson, Céline ULg; Lambert, Stéphanie ULg; Cattoën, Xavier et al

Poster (2009)

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See detailIn situ observation of wall effects in activated carbon filters by X-ray microtomography
Léonard, Angélique ULg; Wullens, Hilda; Blacher, Silvia ULg et al

in Separation & Purification Technology (2008), 64(1), 127-130

X-ray microtomography is a powerful non-invasive visualisation technique which can be advantageously used to get a better understanding or dynamic adsorption processes. In the present work, this technique ... [more ▼]

X-ray microtomography is a powerful non-invasive visualisation technique which can be advantageously used to get a better understanding or dynamic adsorption processes. In the present work, this technique is shown to be able to detect wall effects during the dynamic adsorption of methyl iodide on activated carbon filters. The analysis of transversal cross-sections along the filter height clearly shows the existence of radial concentration profiles. These radial adsorption profiles are directly linked to velocity profiles due to a higher permeability at the wall. Obtaining Such in situ information constitutes a real progress in order to validate simulation models allowing predicting reliable breakthrough times. (C) 2008 Elsevier B.V. All rights reserved. [less ▲]

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See detailIn situ photoacoustic spectroscopy of phycobiliproteins in Gracilaria chilensis
Saavedra, R.; Figueroa, Maximiliano ULg; Wandersleben, T. et al

in Journal de Physique IV (2005), 125

Phycobiliproteins, the main polypeptidic components of the phycobilisomes (PBS), are biolog- ical macromolecules arranged in complex interaction systems to perform light harvesting and conduction. The ... [more ▼]

Phycobiliproteins, the main polypeptidic components of the phycobilisomes (PBS), are biolog- ical macromolecules arranged in complex interaction systems to perform light harvesting and conduction. The optical properties of these systems can hardly be studied by conventional spectroscopic techniques. Furthermore this techniques also involve laborious chemical extraction methods. Photoacoustic (PA) spec- troscopy was successfully applied to an in situ study of the phycobiliproteins expression in the eukaryotic red algae: Gracilaria chilensis. [less ▲]

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See detailThe in situ polymerization of monoethylenically unsaturated monomers with oligomeric or polymeric secondary amines
Detrembleur, Christophe ULg; Rüdiger, Claus; Meyer, Rolf-Volker

Patent (2006)

A process for the preparation of (co)oligomers or (co)polymers is disclosed. The process entails first the preparation of a mixture that contains a monoethylenically unsaturated monomer conforming to HR<1 ... [more ▼]

A process for the preparation of (co)oligomers or (co)polymers is disclosed. The process entails first the preparation of a mixture that contains a monoethylenically unsaturated monomer conforming to HR<1>C = CR<2>R<3> an oxidizing agent and at least one polymer or oligomer conforming to formula (I), <CHEM> and an optional free radical initiator and then heating the mixture at a temperature in the range of 0 DEG C to 220 DEG C. [less ▲]

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