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See detailFull-electrochemical preparation of conducting/insulating binary polymer films
Jérôme, Christine ULg; Geskin, V.; Lazzaroni, Roberto et al

in Chemistry of Materials (2001), 13(5), 1656-1664

Binary polymer films consisting of an insulating polymer and a conducting polymer have been successfully prepared by sequential electropolymerization of the parent monomers. The insulating polymer ... [more ▼]

Binary polymer films consisting of an insulating polymer and a conducting polymer have been successfully prepared by sequential electropolymerization of the parent monomers. The insulating polymer (polyacrylonitrile or polyethylacrylate) is formed under cathodic polarization in a potential range where the growing chains are chemically grafted onto the nickel or carbon electrode. The conducting polymer (polybithiophene or polypyrrole) is formed by electrooxidation of the parent monomer. The electrochemical reactions and the electrochemical properties of the films have been analyzed by cyclic voltammetry and chronoamperometry. The influence of the main experimental parameters on the composition and morphology of the films has been investigated by X-ray photoelectron spectroscopy and atomic force microscopy. This approach strongly improves the adhesion of the conducting polymer as a result of its combination with the grafted polyacrylonitrile. This combination of insulating and conducting polymers is a way to tune the electroactivity of the conjugated chains. [less ▲]

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See detailFull-scale fire test on a composite floor slab incorporating long span cellular steel beams
Nadjai, Ali; Bailey, Colin; Vassart, Olivier et al

in Structural Engineer (2011), 89(21), 18-25

As part of an international major research initiative, dealing with the behaviour of long span cellular beams in steel framed buildings under fire, a large-scale fire test incorporating 15m long cellular ... [more ▼]

As part of an international major research initiative, dealing with the behaviour of long span cellular beams in steel framed buildings under fire, a large-scale fire test incorporating 15m long cellular beams was carried out. The test incorporated unprotected secondary cellular steel beams acting compositely with the supporting floor slab. The floorplate in its entirety was designed to carry the load with unprotected beams, when subjected to a severe fire, by utilising membrane action of the floor slab. The overall structure performed very well supporting the full applied static load for the duration of the test. The unprotected cellular steel beams were subjected to distortional buckling, with only the top tee providing any support through catanary action. The test supported the assumptions adopted in the structural design approach and provided an accurate estimate of the strength of the floorplate. Comparison of the recorded time-temperature relationship of the fire with the design method presented in the Eurocodes shows that the code under-predicts the severity of the fire, although this was compensated to some extent by the conservative assumptions embedded within the structural model. [less ▲]

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See detailFULL-SCALE SEISMIC TESTING OF MODERN UNREINFORCED THERMAL INSULATION CLAY BLOCK MASONRY HOUSES
Mendes, Luis; Candeias, Paulo; Correia, A et al

in Proceedings of the 9th International Masonry Conference 2014 (2014)

In the scope of the transnational access activities of the European research project SERIES, the Laboratório Nacional de Engenharia Civil (LNEC) has provided access to its 3-D shaking table to the ... [more ▼]

In the scope of the transnational access activities of the European research project SERIES, the Laboratório Nacional de Engenharia Civil (LNEC) has provided access to its 3-D shaking table to the international construction company Wienerberger AG and to a group of European experts, in order to perform full-scale seismic tests on an industrial solution for buildings using a modern unreinforced thermal insulation clay block masonry structure. Such solution represents a very common construction method in Central Europe and, although there are cyclic shear test results available, its effective dynamic response under seismic events still requires experimental validation. For this purpose, two full-scale mock-ups with different geometries were tested on the 3-D shaking table using a series of seismic records with increasing intensity. This paper focuses on the most relevant experimental results regarding the structural response of the specimens, e.g., the dynamic response evolution, the collapse mechanism identified and the maximum drift values measured. The paper closes with the main conclusions drawn and with proposals for future developments. [less ▲]

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See detailFull-scale tests of torsional damper and detuner (TDD) antigalloping device
Lilien, Jean-Louis ULg; Vinogradov, Alexander

in IEEE Transactions on Power Delivery (2002), 17(2), 638-643

A new antigalloping device for overhead lines with bundle conductors was introduced ten years ago, after laboratory tests and observations on actual 400-kV lines. A systematic fullscale test was performed ... [more ▼]

A new antigalloping device for overhead lines with bundle conductors was introduced ten years ago, after laboratory tests and observations on actual 400-kV lines. A systematic fullscale test was performed in Kazakhstan in order to better evaluate torsional damper and detuner (TDD) efficiency. This report details the test station and the results obtained over a several month period of testing and measurement. The tests were carried out thanks to the mutual efforts of the ESSP and the Kazakh Power Research Institute (KazNIIE) at the field tests stand located in Chokpar. [less ▲]

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See detailFull-system RANS of the HyShot II scramjet Part 1: Numerics and non-reactive simulations
Pecnik, Rene; Terrapon, Vincent ULg; Ham, Frank et al

in Annual Research Briefs (2010)

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See detailFull-system RANS of the HyShot II scramjet Part 2: Reactive cases
Terrapon, Vincent ULg; Pecnik, Rene; Ham, Frank et al

in Annual Research Briefs (2010)

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See detailFull-system simulation of the HyShot II scramjet
Terrapon, Vincent ULg

Scientific conference (2011, May)

The renewed interest in high-speed flight has recently demonstrated the need for the development of hypersonic air-breathing propulsion systems, i.e., in which the ambient air is used as oxidizer. Because ... [more ▼]

The renewed interest in high-speed flight has recently demonstrated the need for the development of hypersonic air-breathing propulsion systems, i.e., in which the ambient air is used as oxidizer. Because the internal flow in a scramjet is supersonic, it has a very short residence time during which air and fuel must mix on a molecular level, and chemical reactions have to be completed before leaving the engine. Moreover, the kinetic energy of the free stream of air entering the propulsion engine is of the same order of magnitude as the combustion heat re- lease. This results in a small net thrust compared to the aerodynamic drag. On the other hand, an excessive heat release can lead to the unstart phenomenon, i.e., the choking of the engine, that causes a sudden drop in thrust and large mechanical loads on the structure. Performance optimization requires thus maximizing thrust without crossing the unstart bound. To achieve predictive computations, the quantification of margins and uncertainties (QMU) with respect to this unstart bound is critical. Recent advances within the PSAAP program at Stanford University to develop computational tools to study the unstart phenomenon will be presented. In the first part, an overview of the program will be given. The second part will focus on the combustion model. Since heat release is at the heart of a scramjet operation and the main contributor to unstart, it is also the major source of uncertainties. A novel model for supersonic combustion based on a flamelet/progress variable approach has been developed. This approach allows the use of com- plex chemistry with only 2 or 3 additional scalar transport equations. The model is applied in a RANS computation of the hydrogen fueled HyShot II scramjet and simulation results are compared with experimental data. LES results for a jet in a supersonic crossflow will also be presented. [less ▲]

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See detailFullerene containing (co)polymers for biomedical applications
Stoilova, Olya; Detrembleur, Christophe ULg; Jérôme, Christine ULg et al

Conference (2005, June 01)

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See detailFully and Partially Reusable TSTO launchers using In-Flight LOX Collection
Hendrick, Patrick; Breugeulmans, F.; Marquet, B. et al

in 22nd International Symposium on Space Technology and Science (ISTS) (2000, May)

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See detailA fully aqueous sustainable process for strongly adhering antimicrobial coatings on stainless steel
Cécius, Michaël; Jérôme, Christine ULg

in Progress in Organic Coatings (2011), 70(1), 220-223

In order to provide conducting surfaces with antibacterial properties, the electrografting of acrylate has been combined with the layer-by-layer deposition of polyelectrolytes. The challenges addressed by ... [more ▼]

In order to provide conducting surfaces with antibacterial properties, the electrografting of acrylate has been combined with the layer-by-layer deposition of polyelectrolytes. The challenges addressed by this strategy are (i) to insure the adhesion of the biocidal coating to the conducting surface and (ii) to avoid the use of organic solvents in the coating process. The electrografting process has been implemented in water and allows imparting strong adhesion of an anchoring polycationic layer, used in a second step for growing a chitosan-based bactericidal coating by layer-by-layer deposition. This novel process based on readily available precursors allows the coating from aqueous media and makes the coating technology quite sustainable. [less ▲]

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See detailFully automated electrophoretically mediated microanalysis for CYP1A1 activity monitoring optimized by multivariate approach
Farcas, Elena ULg; Servais, Anne-Catherine ULg; Lamalle, Caroline ULg et al

in Electrophoresis (2016), 37(2), 248-255

In this study, a fully automatized in-capillary system was developed to monitor the activity of CYP1A1 in physiological conditions. Ethoxycoumarin, the selected substrate, undergoes an in-line bioreaction ... [more ▼]

In this study, a fully automatized in-capillary system was developed to monitor the activity of CYP1A1 in physiological conditions. Ethoxycoumarin, the selected substrate, undergoes an in-line bioreaction in the presence of CYP1A1 supersomes and NADPH as co-factor, giving rise to hydroxycoumarin, the product that was assayed. The optimization of the experimental conditions was supported by the application of a design of experiment, providing a better understanding of electrophoretic mixing parameters that influence the metabolic reactions. The results obtained in optimal conditions were compared not only to those achieved after off-line metabolization but also with liver microsomes. Finally, inhibition studies were conducted showing an important decrease of hydroxycoumarin formation using apigenin as CYP1A1 potent inhibitor. This study demonstrates the usefulness of our in-line system for the fully automated in vitro metabolism studies and the screening of new CYP1A1 inhibitors. [less ▲]

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See detailFully Automated Determination of Sulfamethazine in Ovine Plasma Using Solid-Phase Extraction on Disposable Cartridges and Liquid Chromatography
Hubert, Philippe ULg; Chiap, Patrice ULg; Evrard, Brigitte ULg et al

in Journal of Chromatography. A (1993), 622(1), 53-60

An automatic sample preparation procedure followed by on-line injection of the sample extract into a HPLC system has been developed for the quantitative analysis of sulfamethazine and its N4-acetyl ... [more ▼]

An automatic sample preparation procedure followed by on-line injection of the sample extract into a HPLC system has been developed for the quantitative analysis of sulfamethazine and its N4-acetyl metabolite in ovine plasma. The sample clean-up was performed by solid-phase extraction (SPE) on C18 disposable extraction cartridges (DECs). All the sample handling operations were effected by a robotic auto-sampler. The DEC was first conditioned with methanol and phosphate buffer pH 7.4. After loading 1.0 ml of plasma sample onto the DEC, the latter was washed with the same buffer. The elution step was performed with methanol (0.25 ml) and the eluate was then diluted by adding 0.75 ml volume of phosphate buffer pH 6.4. A 20-microliters volume of the resultant solution was injected onto an octadecyl silica column preceded by a short guard column. The HPLC mobile phase was methanol-phosphate buffer pH 6.4 (25:75, v/v). Sulfamethazine and N4-acetylsulfamethazine were determined photometrically at 262 nm. Under these conditions, linear calibration curves ranging from 2 to 250 micrograms ml-1 have been obtained for both compounds. Drug recoveries were higher than 90% and typical relative standard deviation values were 0.7% (within-day) and 2.0% (between-day) at a plasma concentration of 50 micrograms ml-1. [less ▲]

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See detailFULLY AUTOMATED ELECTROPHORETICALLY MEDIATED MICROANALYSIS SYSTEM FOR CYP1A1 ACTIVITY MONITORING
Farcas, Elena ULg; Servais, Anne-Catherine ULg; Lamalle, Caroline ULg et al

Poster (2015, June 23)

Introduction Since the efficacy and toxicity of drugs are closely related to their pharmacokinetics, a good understanding of metabolic pathways is important at an early stage of development. The ... [more ▼]

Introduction Since the efficacy and toxicity of drugs are closely related to their pharmacokinetics, a good understanding of metabolic pathways is important at an early stage of development. The identification of the enzymes involved in drug metabolism is thus of critical importance for the design of further clinical studies. The availability of specifically expressed human CYPs, namely supersomes, allows the investigation of the contribution of a single metabolic enzyme to the biotransformation pathway of the compound under investigation. CYP1A1, a member of the cytochrome P450 superfamily, was studied in this project. Interestingly, it has been described to be over expressed in various types of cancer. Consequently, CYP1A1 has emerged as a particularly interesting target for cancer therapy. Methods All the experiments were carried out on a HP3DCE system equipped with an on-column DAD. The EMMA procedure was performed by injecting a plug containing CYP1A1 supersomes, followed by a plug that contained the co-factor and the substrate, then another plug of CYP1A1 supersomes. The reaction was triggered by the application of a voltage switch. The voltage was then turned off to allow the metabolic reaction to occur. The separation of the components was then performed at -25 kV. Results The present study describes the development of a fully automatized in-capillary method to follow metabolization of 7-hydroxycoumarin and screen CYP1A1 inhibitors. After preliminary studies, satisfying results were obtained using CYP1A1 at a concentration of 200 pmol/mL, while the incubation time was settled to 15 min. Equal reactant plugs were injected at -50 mbar for 6 sec. The short-end injection performed gave rise to a baseline separation of the molecules (substrate, product, CYP1A1 and NADPH) in less than 2 minutes. Adequate plugs overlap was obtained using electrophoretic mixing. The DoE performed highlighted that the voltage switch has a great impact on the metabolite formation. The amount of product obtained in the optimal conditions was found to be comparable to the one detected after conventional off-line metabolization. Besides the interest of developing an automatized CE approach for metabolisation studies, we also wanted to investigate the potentiality of this approach to screen CYP1A1 inhibitors. The ability of our system to monitor CYP1A1 inhibition was undertaken with apigenin, a well-known inhibitor. It is noteworthy that the compatibility of our system with MEKC ensures its applicability to a large variety of molecules. Novel aspect Monitoring CYP1A1 activity using a rapid and fully automated EMMA method that could be used for new anticancer agents screening. [less ▲]

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See detailFully automated electrophoretically mediated microanalysis system for CYP1A1 activity monitoring
Farcas, Elena ULg; Servais, Anne-Catherine ULg; Lamalle, Caroline ULg et al

Conference (2015, May 28)

In order to evaluate the potentiality of capillary electrophoresis for CYP1A1 activity monitoring, an in-line method was developed with the well-known 7-ethoxycoumarin substrate. The electrophoretically ... [more ▼]

In order to evaluate the potentiality of capillary electrophoresis for CYP1A1 activity monitoring, an in-line method was developed with the well-known 7-ethoxycoumarin substrate. The electrophoretically mediated microanalysis approach was used with CYP1A1 supersomes to provide a rapid and fully automated method. The in-line homogenous enzyme assay was performed in physiological conditions (pH 7.4), whereas a MEKC buffer was used as background electrolyte. In order to reduce the analysis time, the short end injection was performed. Firstly a plug containing CYP1A1 supersomes was hydrodynamically injected into a fused silica capillary, followed by a plug of co-factor (NADPH) and substrate (7-ethoxycoumarin) and finally another plug of CYP1A1 (sandwich mode). The experimental conditions were finely investigated and tuned by design of experiment methodology. The metabolization rate measured in the optimized conditions was comparable with the one obtained after off-line metabolization. Finally, inhibition studies were conducted and a significant decrease of 7-hydroxycoumarin formation was observed using apigenin as CYP1A1 potent inhibitor. [less ▲]

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See detailFully automated heart rate variability assessment in dairy cows
Janda, Jozef; Guyot, Hugues ULg; Sandersen, Charlotte ULg et al

in Acta Physiologica (2006, May), 187(Suppl 651), -16

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See detailA Fully Automated High-Performance Liquid Chromatographic Method for the Determination of Indomethacin in Plasma
Hubert, Philippe ULg; Renson, M.; Crommen, Jacques ULg

in Journal of Pharmaceutical & Biomedical Analysis (1989), 7(12), 1819-27

A fully automated method is described, which enables the determination of indomethacin in plasma by reversed-phase HPLC following on-line sample enrichment and clean-up on a short pre-column. The plasma ... [more ▼]

A fully automated method is described, which enables the determination of indomethacin in plasma by reversed-phase HPLC following on-line sample enrichment and clean-up on a short pre-column. The plasma sample is introduced directly into the column switching system. The pre-column, filled with a pellicular bonded phase, is first washed with phosphate buffer, pH 7.4. The compounds retained on the pre-column are then eluted in the fore-flush mode and separated on an octadecylsilica column with a methanolic phosphate buffer (pH 7.4) mobile phase. Indomethacin is determined spectrophotometrically at 254 or 260 nm. The effect of changes in the pH and flow rate of the washing eluent are studied. Under the conditions selected, memory effects can be avoided, the absolute recovery of the drug is 70% and the limit of detection 10 ng ml-1 for a 100 microliter injection of plasma. At a concentration of 100 ng ml-1, the relative standard deviations (RSD) are 1.7% (within-day) and 3.5% (between-day), respectively. [less ▲]

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