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Peer Reviewed
See detailElectro-Mechano-Fluidic Modelling of Microsystems using Finite Elements
Rochus, V.; Gutschmidt, S.; Cardona, A. et al

in Proceedings of the 18th Conference on the Computation of Electromagnetic Fields (COMPUMAG 2011) (2011, July)

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See detailElectro-Mechano-Fluidic Modelling of Microsystems using Finite Elements
Rochus, V.; Gutschmidt, S.; Cardona, A. et al

in IEEE Transactions on Magnetics (2012), 48(2), 355-358

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See detailElectro-optic coefficient measurements : correction of electric-field inhomogeneities in the transverse configuration
Lemaire, Philippe; Georges, Marc ULg

in Optics Letters (1992), 17(20), 1411-1413

The problem of electric-field inhomogeneities in the measurement of the electro-optic coefficient in the transverse configuration is well known. We present a simple way to solve these difficulties. It ... [more ▼]

The problem of electric-field inhomogeneities in the measurement of the electro-optic coefficient in the transverse configuration is well known. We present a simple way to solve these difficulties. It involves local measurements at several points along the transverse direction of the phase difference between two components of light traveling through the crystal. The electro-optic coefficient is simply calculated by integrating the phase shifts along the transverse profile. For this procedure one needs nothing but the value of the voltage applied to the crystal, and knowledge of the internal electric field is not necessary. Limits of application are discussed, and results are shown for photorefractive sillenite crystals. [less ▲]

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See detailElectroantennogram of Culex quinquefasciatus Say (Diptera:Culicidae) to chemical compounds from fermented infusions and improvement of gravid mosquito trapping
Latte, Nicolas ULg

Master's dissertation (2006)

The urban mosquito Culex quinquefasciatus Say (Diptera: Culicidae) uses chemicals to locate suitable water pools for oviposition. These chemicals when identified can be used to trap gravid female ... [more ▼]

The urban mosquito Culex quinquefasciatus Say (Diptera: Culicidae) uses chemicals to locate suitable water pools for oviposition. These chemicals when identified can be used to trap gravid female mosquitoes. Experiments in Davis and in Sacramento (California, in the United States) were made to improve the trapping efficiency of Reiter/Cumming gravid traps baited by several attractants (or attractant blends). Unfortunately, it appeared that the number of gravid female mosquitoes collected was not sufficient to differentiate the efficacy of attractant blends tested by statistical analysis. However, a positive correlation between the total mosquito number collected daily and the highest humidity shows that the mosquito oviposition activity seems to be influenced by the humidity during the night. Observations on total number of mosquitoes and the highest temperature seem to reveal a threshold temperature which is critical for the adult mosquito survival. A coupled gas chromatography – electronantennography (GC-EAD) protocol was also developed step by step in order to find new Culex quinquefasciatus oviposition attractants. After obtaining repetitive electroantennographic (EA) response, two comparison experiments (SPME fiber type and infusion type) were made to finalize the specific GC-EAD/SPME protocol. This with the aim to prospect new attractants from fermented Bermuda grass infusion. Analyses based on all results permit to distinguish the EA responses from random perturbations (electromagnetic and vibration). GC-EAD/SPME of Bermuda grass infusion analyses confirms the presence of 10 and the activity of 9 chemical compounds as established by Du and Millar in 1999. Furthermore, experiments on Culex quinquefasciatus performed with the new protocol, brought to light the EA activity of 10 other unknown chemicals, 7 of which are low molecular weight chemical compounds. These new chemicals have now to be identified and their ability to elicit EA responses still has to be confirmed. [less ▲]

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See detailElectrocardiographic changes during dobutamine stress testing in patients with recent myocardial infarction: relation with residual infarct artery stenosis and contractile recovery
Lancellotti, Patrizio ULg; Mipinda, J. B.; Pierard, L. A.

in Acta Cardiologica (2004), 59(1), 11-16

OBJECTIVE: The identification of viable but jeopardized myocardium after acute myocardial infarction (AMI) is of great importance for selecting patients who could benefit from a revascularization ... [more ▼]

OBJECTIVE: The identification of viable but jeopardized myocardium after acute myocardial infarction (AMI) is of great importance for selecting patients who could benefit from a revascularization procedure. The aim of the study was to determine the accuracy of the dobutamine stress electrocardiogram (ECG) 1) for detecting significant stenosis of the infarct-related artery and 2) for predicting the occurrence of contractile recovery. METHODS AND RESULTS: Ninety-four patients underwent dobutamine stress ECG and quantitative angiography within the first week after AMI. A follow-up resting echocardiogram was obtained in all patients at 1 month. Significant stenosis of the infarct-related artery was detected in 76 patients and functional recovery occurred in 56 patients. Dobutamine stress induced ST-segment elevation in 44 patients, ST-segment depression in 17 and T-wave normalization in 34. Increase in QT dispersion and dobutamine ST elevation were more sensitive than chest pain and ST-segment depression (79% and 53% vs. 24% and 17%, respectively; p<0.05) for detecting significant infarct-related artery stenosis. Four independent variables were selected for predicting contractile recovery: > or = 20 ms increase in QT dispersion from baseline to low-dose dobutamine (p = 0.00016), dobutamine-induced ST-segment elevation (p = 0.0009), elective angioplasty of the infarct-related artery (p = 0.001) and T-wave normalization (p = 0.005). CONCLUSIONS: The analysis of predischarge dobutamine stress ECG is useful for predicting residual stenosis of the infarct-related artery and contractile recovery in the affected area. QT dispersion changes during the test are the most accurate parameter. [less ▲]

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See detailElectrochemical and PM-IRRAS characterization of cholera toxin binding at a model biological membrane.
Leitch, J. Jay; Brosseau, Christa L.; Roscoe, Sharon G. et al

in Langmuir : the ACS journal of surfaces and colloids (2013), 29(3), 965-76

A mixed phospholipid-cholestrol bilayer, with cholera toxin B (CTB) units attached to the monosialotetrahexosylganglioside (GM1) binding sites in the distal leaflet, was deposited on a Au(111) electrode ... [more ▼]

A mixed phospholipid-cholestrol bilayer, with cholera toxin B (CTB) units attached to the monosialotetrahexosylganglioside (GM1) binding sites in the distal leaflet, was deposited on a Au(111) electrode surface. Polarization modulation infrared reflection absorption spectroscopy (PM-IRRAS) measurements were used to characterize structural and orientational changes in this model biological membrane upon binding CTB and the application of the electrode potential. The data presented in this article show that binding cholera toxin to the membrane leads to an overall increase in the tilt angle of the fatty acid chains; however, the conformation of the bilayer remains relatively constant as indicated by the small decrease in the total number of gauche conformers of acyl tails. In addition, the bound toxin caused a significant decrease in the hydration of the ester group contained within the lipid bilayer. Furthermore, changes in the applied potential had a minimal effect on the overall structure of the membrane. In contrast, our results showed significant voltage-dependent changes in the average orientation of the protein alpha-helices that may correspond to the voltage-gated opening and closing of the central pore that resides within the B subunit of cholera toxin. [less ▲]

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See detailElectrochemical and spectroscopic study of the self-assembling mechanism of normal and chelating alkanethiols on copper
Dilimon, V. S.; Denayer, Jessica ULg; Delhalle, J. et al

in Langmuir (2012), 28(17), 6857-6865

The self-assembly of aliphatic thiol (RSH), dithiol (R(SH) 2), and dithiocarboxylic acid (RS 2H) onto mildly oxidized and highly oxidized copper was studied in real time by in situ electrochemical ... [more ▼]

The self-assembly of aliphatic thiol (RSH), dithiol (R(SH) 2), and dithiocarboxylic acid (RS 2H) onto mildly oxidized and highly oxidized copper was studied in real time by in situ electrochemical impedance spectroscopy (EIS). Ex situ characterization of the films was carried out using linear sweep voltammetry (LSV), polarization modulation infrared reflection absorption spectroscopy (PM-IRRAS), and X-ray photoelectron spectroscopy (XPS). In situ EIS studies found a very fast adsorption of RSH, R(SH) 2, and RS 2H (within 10-15 s). This fast adsorption step is followed by the long-term additional adsorption and consolidation of SAM. However, the self-assembly of RS 2H passes through an intermediate step of molecule rearrangement for around 10 to 30 min after around 2 to 7 min of self-assembly. The binding of both sulfur moieties of R(SH) 2 with Cu happens simultaneous. The oxide reduction capacity of RSH, R(SH) 2, and RS 2H was good. However, the XPS studies showed the decomposition of RS 2H-based SAMs to Cu 2S. Monolayers prepared on both mildly oxidized and heavily oxidized Cu with R(SH) 2 had the highest stability. Monolayers of RS 2H showed the least stability on both mildly oxidized and heavily oxidized Cu. Although RSH-based SAMs had good organization on both mildly oxidized and highly oxidized Cu, R(SH) 2-based SAMs did not show good organization in either case. The RS 2H monolayer had good organization only on mildly oxidized Cu. © 2012 American Chemical Society. [less ▲]

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See detailElectrochemical characterization of Pt/carbon xerogel and Pt/carbon aerogel catalysts
Job, Nathalie ULg; Maillard, F.; Marie, J. et al

Poster (2008, September 08)

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See detailElectrochemical Co-Deposition of Phosphonate-Modified Carbon Nanotubes and Tantalum on Nitinol
Maho, Anthony ULg; Detriche, Simon; Fonder, Grégory et al

in ChemElectroChem (2014), 1(5), 896--902

Nitinol substrates are coated with thin surface films made of carbon nanotubes (CNTs) and tantalum (Ta), with the aim of fostering their osseointegration aptitudes. Exceptional mechanical and chemical ... [more ▼]

Nitinol substrates are coated with thin surface films made of carbon nanotubes (CNTs) and tantalum (Ta), with the aim of fostering their osseointegration aptitudes. Exceptional mechanical and chemical characteristics of CNTs combined with the resistance to corrosion and strong bioactive properties of tantalum allow for the generation of adherent, protective and functional layers on metallic biomaterial platforms. The composite coatings are elaborated on Nitinol through a two-step electrochemical protocol; firstly, through the electrophoretic deposition of phosphonate-modified CNTs and, secondly, with electrodeposition of Ta. As a preliminary step, phosphonate groups, acting, in addition, as specific Ta-capture entities, are introduced on the CNT sidewalls by means of diazonium derivatives, which imply no hard oxidative treatment. X-ray photoelectron spectroscopy as well as scanning and transmission electronic microscopies are used to analyse the chemical composition, structure and morphology of the different layers. [less ▲]

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See detailElectrochemical formation of polypyrrole nanowires
Jérôme, Christine ULg; Labaye, David; Jérôme, Robert ULg

in Synthetic Metals (2004), 142(1-3), 207-216

This paper aims at approaching the mechanism of formation of polypyrrole (PPy) nanowires by an all-electrochemical process, which consists in electrografting a poly(alkylacrylate) film onto the surface of ... [more ▼]

This paper aims at approaching the mechanism of formation of polypyrrole (PPy) nanowires by an all-electrochemical process, which consists in electrografting a poly(alkylacrylate) film onto the surface of a cathode, followed by the anodic electropolymerization of pyrrole (Py) at the surface of this organomodified electrode. The experimental conditions for the pyrrole oxidation, including solvent and concentrations of monomer and supporting electrolyte, have been changed with the purpose to tune the characteristic features of the polypyrrole nanowires. The polyacrylate template has also been modified, all other conditions being the same, in an effort to design the shape and size of the wires. The electrochemical behavior of the as-prepared PPy wires has been characterized. [less ▲]

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See detailElectrochemical Investigation of Nitinol/Tantalum Hybrid Surfaces Modified by Alkylphosphonic Self-Assembled Monolayers
Maho, Anthony ULg; Kanoufi, Frédéric; Combellas, Catherine et al

in Electrochimica Acta (2014), 116(0), 78-88

The surface characteristics of bare and modified nickel-titanium samples (NiTi) are investigated by spectroscopic, microscopic and electrochemical techniques. The successful electrodeposition of a ... [more ▼]

The surface characteristics of bare and modified nickel-titanium samples (NiTi) are investigated by spectroscopic, microscopic and electrochemical techniques. The successful electrodeposition of a tantalum coating on NiTi and the effective grafting of 1-dodecylphosphonic acid SAMs on both pristine and Ta-covered NiTi surfaces are evidenced and quantified by XPS and SEM. Cyclic voltammetry performed on the different NiTi-based electrodes highlights their specificities regarding electron transfer to a redox probe present in solution (here ruthenium(III) hexamine). Finally, the samples electrochemical characteristics at a local scale are investigated by scanning electrochemical microscopy (SECM). The impact of the surface modifications on mass transport of the redox probe is analyzed through approach curves in the feedback mode, while the recording of current maps in feedback as well as in substrate-generation/tip-collection modes leads to the qualitative identification of electrochemically-active areas corresponding to precursor pitting corrosion sites. [less ▲]

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See detailElectrochemical strategies for the strengthening of polymer – metal interfaces
Baute, Noëlle; Jérôme, Christine ULg; Martinot, Lucien et al

in European Journal of Inorganic Chemistry (2001), 2001(5), 1097-1107

Polymers have been widely used for the protection of metals against corrosion and for improving the performance of structural adhesive joints. In this contribution, the weakness and short-term durability ... [more ▼]

Polymers have been widely used for the protection of metals against corrosion and for improving the performance of structural adhesive joints. In this contribution, the weakness and short-term durability of these polymer-metal interactions and some common approaches for alleviating this problem are briefly reviewed. Among the existing techniques, electrochemical processes offer the advantage of controlled interfacial reactions. Promising results have been reported by Strat-mann et al. and Le´cayon et al., who have emphasized the interest and opportunity to create strong chemical bonds between the organic coating and the metallic substrate. Their work is discussed in this review, along with results recently obtained in our group [less ▲]

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See detailElectrochemical study of the uranium exchange by polypyrrole-based resins
Jérôme, Christine ULg; Martinot, Lucien; Jérôme, Robert ULg

in Journal of Applied Polymer Science (1999), 74(14), 3473-3484

Electrochemical control of the binding of uranium ions by redox active polypyrrole resins was studied. The experimental conditions for this binding were optimized with respect to the uranium ions to be ... [more ▼]

Electrochemical control of the binding of uranium ions by redox active polypyrrole resins was studied. The experimental conditions for this binding were optimized with respect to the uranium ions to be fixed, the resin, and the solution. [less ▲]

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See detailElectrochemical study of two tris-O-substituted calix[4]arenes: 25,27-dipropoxy-26-hydroxy-28-benzoyloxycalix[4]arene(partial cone) and 25,27-dibenzyl-26-hydroxy-28-benzoyloxy-calix[4]-arene (partial cone). Electro synthesis of the corresponding calix[4]arene-monoquinones
Louati, Alain; Spraula, Julien; Gabelica, Valérie ULg et al

in Electrochemistry Communications (2006), 8(5), 761-766

The anodic oxidation of 25,27-dipropoxy-26-hydroxy-28-benzoyloxycalix[4]arene 1 and 25,27-dibenzyl-26-hydroxy-28-benzoyloxycalix[4]arene 2 in dichloromethane was investigated by electrochemical and ... [more ▼]

The anodic oxidation of 25,27-dipropoxy-26-hydroxy-28-benzoyloxycalix[4]arene 1 and 25,27-dibenzyl-26-hydroxy-28-benzoyloxycalix[4]arene 2 in dichloromethane was investigated by electrochemical and spectroclectrochemical techniques. For both, the overall reaction is a two-electron oxidation of the phenolic group according to an ECE mechanism resulting in the ultimate formation of an observable phenoxylium cation. After reaction of the latter with traces of water and subsequent internal electron transfer, the corresponding calix[4]-monoquinones are formed. (c) 2006 Elsevier B.V. All rights reserved. [less ▲]

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See detailElectrochemical study of uranium exchange on a polypyrrole resin
Jérôme, Christine ULg; Martinot, Lucien; Jérôme, Robert ULg

in Journal of Radioanalytical & Nuclear Chemistry (1999), 240(3), 969-972

The ability to electrochemically control the binding of uranium ions by redox active polypyrrole resins has been studied. The optimization of the conditions for the fixation of uranium has been defined ... [more ▼]

The ability to electrochemically control the binding of uranium ions by redox active polypyrrole resins has been studied. The optimization of the conditions for the fixation of uranium has been defined while taking in account the nature of the fixed species, the nature of the resin and the nature of the solutions. [less ▲]

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See detailElectrochemical synthesis and characterization of the electronic structure of new conjugated polymers from dithienylene vinylene derivatives
Jérôme, Christine ULg; Maertens, Christophe; Mertens, Marc et al

in Synthetic Metals (1996), 83(2), 103-109

Highly conjugated thiophene derivatives, based on thienylene vinylene and thienylene vinylene phenylene units, have been synthesized in order to examine: (i) the effect of such regular conjugated monomer ... [more ▼]

Highly conjugated thiophene derivatives, based on thienylene vinylene and thienylene vinylene phenylene units, have been synthesized in order to examine: (i) the effect of such regular conjugated monomer structures on polymer formation; and (ii) the optical and electrochemical properties of the corresponding macromolecules. The all-trans monomers have been prepared by a Wittig reaction. The polymers have then been synthesized electrochemically. The polymers are electrochromic and can be reversibly doped both oxidatively and reductively. Their electrochemical behavior and optical properties have been analyzed on the basis of a series of quantum-chemical calculations. [less ▲]

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See detailElectrochemical synthesis of conjugated polymer wires and nanotubules
Jérôme, Christine ULg; Demoustier-Champagne, Sophie; Legras, Roger et al

in Chemistry : A European Journal (2000), 6(17), 3089-3093

Two electrochemical methods designed for the synthesis of polypyrrole (PPy) wires and nanotubules are the topic of this paper. The concept that allows the morphology of PPy to be controlled is discussed ... [more ▼]

Two electrochemical methods designed for the synthesis of polypyrrole (PPy) wires and nanotubules are the topic of this paper. The concept that allows the morphology of PPy to be controlled is discussed for each method, and the performances of the two complementary techniques are compared in terms of dimension, shape and conductivity of PPy. [less ▲]

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See detailElectrochemical synthesis of new electroactive polymers from dithienylene-vinylene derivatives
Jérôme, Christine ULg; Maertens, Christophe; Mertens, Marc et al

in Synthetic Metals (1997, January), 84(1-3), 163-164

Highly conjugated thiophene derivatives, based on thienylene-vinylene and thieneylene-vinylene-phenylene units, have been synthesized in order to examine: (i) the effect of such regular conjugated monomer ... [more ▼]

Highly conjugated thiophene derivatives, based on thienylene-vinylene and thieneylene-vinylene-phenylene units, have been synthesized in order to examine: (i) the effect of such regular conjugated monomer structures on the polymerization; (ii) the optical and electrochemical properties of the corresponding conjugated polymers. The all-trans monomers have been prepared by a Wittig reaction and the polymers have then been synthesized electrochemically. The polymers are electrochromic and can be reversibly doped both oxidatively and reductively. Their electrochemical behavior and optical properties have been analysed on the basis of quantum-chemical calculations. [less ▲]

Detailed reference viewed: 38 (1 ULg)