Browsing
     by title


0-9 A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

or enter first few letters:   
OK
Full Text
Peer Reviewed
See detailElectrical transport and percolation in magnetoresistive manganite/insulating oxide composites: Case of La0.7Ca0.3MnO3/Mn3O4
Vertruyen, Bénédicte ULg; Cloots, Rudi ULg; Ausloos, Marcel ULg et al

in Physical Review. B (2007), 75(16), 165112

We report the results of electrical resistivity measurements carried out on well-sintered La0.7Ca0.3MnO3/Mn3O4 composite samples with almost constant composition of the magnetoresistive manganite phase ... [more ▼]

We report the results of electrical resistivity measurements carried out on well-sintered La0.7Ca0.3MnO3/Mn3O4 composite samples with almost constant composition of the magnetoresistive manganite phase (La0.7Ca0.3MnO3). A percolation threshold (phi c) occurs when the La0.7Ca0.3MnO3 volume fraction is ~ 0.19. The dependence of the electrical resistivity rho as a function of La0.7Ca0.3MnO3 volume fraction fLCMO can be described by percolationlike phenomenological equations. Fitting the conducting regime (fLCMO > phic) by the percolation power law rho # (fLCMO - phic)^(-t) returns a critical exponent value of 2.0±0.2 at room temperature and 2.6±0.2 at 5 K. The increase of t is ascribed to the influence of the grain boundaries on the electrical conduction process at low temperature. (C) 2007 The American Physical Society. [less ▲]

Detailed reference viewed: 106 (21 ULg)
Full Text
Peer Reviewed
See detailElectrical transport in saturated and conjugated molecular wires
Remacle, Françoise ULg; Levine, R. D.

in Faraday Discussions (2006), 131

The mechanism for charge transport in dithio molecular wires tethered between two gold electrodes is investigated, using both a steady state and a time-dependent quantum mechanical approach. The interface ... [more ▼]

The mechanism for charge transport in dithio molecular wires tethered between two gold electrodes is investigated, using both a steady state and a time-dependent quantum mechanical approach. The interface with the electrodes is modeled by two gold clusters and the electronic structure of the entire Au-n-S-bridge-S-Au-n system is computed ab initio at the DFT level and semi-empirically, with the extended Huckel theory. Current vs. applied bias, I-V, curves are computed using a scattering Landauer-type formalism in a steady state picture. The applied source-drain and gate voltages are included at the ab initio level in the electronic Hamiltonian and found to influence strongly the I-V characteristics. The time evolution of a non stationary electronic wave packet initially localized on a gold atom at one end of the extended system shows that charge transfer proceeds sequentially, by a hopping mechanism, to the opposite end. Analysis of the effective one electron Hamiltonian matrix shows that the sulfur atom endows a resistive character to the Au-C-S junctions. The S atoms are however rather well coupled to both the gold and carbon atoms so that typically the super exchange limit for electron transfer is not reached unless the molecular bridge is saturated and the Fermi window function is narrow. [less ▲]

Detailed reference viewed: 9 (3 ULg)
Full Text
See detailElectrical tuned vibration absorber: application of the equal-peak method to linear and non-linear RL piezoelectric shunts
TONDREAU, Gilles; DERAEMAEKER, Arnaud; Soltani, Payam ULg et al

Scientific conference (2014, October)

Detailed reference viewed: 34 (4 ULg)
Full Text
Peer Reviewed
See detailElectrically addressing a molecule-like donor pair in silicon: An atomic scale cyclable full adder logic
YAN, Yonghong; Mol, J. A.; Verduijn, J. et al

in Journal of Physical Chemistry C: Nanomaterials, Interfaces, and Hard Matter (2010), 114

Detailed reference viewed: 47 (0 ULg)
Full Text
Peer Reviewed
See detailElectrically charged droplet: Case study of a simple generator
Brandenbourger, Martin ULg; Dorbolo, Stéphane ULg

in Canadian Journal of Physics (2014), 92

Detailed reference viewed: 28 (3 ULg)
Full Text
Peer Reviewed
See detailElectrically charged droplets in microgravity
brandenbourger, martin; Caps, Hervé ULg; vitry, youen et al

in Microgravity Science and Technology (2017)

Detailed reference viewed: 19 (2 ULg)
Full Text
Peer Reviewed
See detailElectricity storage with liquid fuels in a zone powered by 100% variable renewables
Léonard, Grégoire ULg; François-Lavet, Vincent ULg; Ernst, Damien ULg et al

in Proceedings of the 12th International Conference on the European Energy Market - EEM15 (2015)

In this work, an electricity zone with 100% renewables is simulated to determine the optimal sizing of generation and storage capacities in such a zone. Using actual wind output data, the model evaluates ... [more ▼]

In this work, an electricity zone with 100% renewables is simulated to determine the optimal sizing of generation and storage capacities in such a zone. Using actual wind output data, the model evaluates the economic viability of a power-to-fuel storage technology that combines water electrolysis, CO2 capture and methanol synthesis. The main advantage of using methanol as an energy carrier is that liquid fuels are suitable for (long-term) energy storage thanks to their high energy density. The levelized electricity cost projection by 2050 equals 83.4 €/MWh in the base case configuration. The effects of storage round-trip efficiency and the storage unit lifetime are quantified and their impacts on the electricity cost discussed. Additional benefits of using methanol as a fuel substitute may be taken into account in further work. [less ▲]

Detailed reference viewed: 858 (51 ULg)
Full Text
Peer Reviewed
See detailElectrification Rurale. Vers une technique innovatrice pour l'Afrique.
Lilien, Jean-Louis ULg; omboua, Alphonse

in Revue d'electricité et d'électronique industrielle (2006), N°1-2006

In many developing countries , there are a lot of high voltage lines which cross many regions to supply electricity to the main towns or connect to networks the distanced electric substations . These ... [more ▼]

In many developing countries , there are a lot of high voltage lines which cross many regions to supply electricity to the main towns or connect to networks the distanced electric substations . These lines, used for supplying electricity to big towns, cross a lot of villages whose people broadly poor hope to be supplied with electricity without a suitable solution. However it seems very deplorable that the power conducted by these lines doesn’t profit to surrounding population. Unfortunately , for these villages , the use of classical substations is too expensive to the power distributors because of high cost of investment and production for these potential scattered consumers with the low demand of electricity. This paper presents the original solution settled in 2002 in one of the village located in Congo Brazzaville and continue to operate correctly in 2006. It is a new power transformer, based on the technique of SF6 measuring transformer, which is connected on one phase of the high voltage line 220kV and which produces the low voltage 230 V directly useful by the rural population. This prototype sample for the rural electrification has been designed to deliver a power of 50kVA. A cheap and robust system ! It requires a large popularization, mainly in sub saharian Africa that has got many such opportunities. Outside the role of bulk power transmission, the high voltage line is now also able to distribute a part of it. [less ▲]

Detailed reference viewed: 226 (11 ULg)
Full Text
Peer Reviewed
See detailElectro dynamic fragmentation of printed wiring boards as a preparation tool for their recycling
Martino, Rémi; Iseli, Cedric; Gaydardzhiev, Stoyan ULg et al

in Minerals Engineering (2017), 107

The use of Electro Dynamic Fragmentation (EDF) enables selective fragmentation of materials through generating electrical discharges as a means of fracturing. Liberated materials can be thus processed ... [more ▼]

The use of Electro Dynamic Fragmentation (EDF) enables selective fragmentation of materials through generating electrical discharges as a means of fracturing. Liberated materials can be thus processed downstream in a more efficient way especially when value-added End-of-Life (EoL) electronic equipment is recycled. The aim of this study was to assess the benefits of the EDF technology towards processing of EoL printed wiring boards (PWBs) in view their recyclability. Printed wiring boards were comminuted using EDF at three different settings and with a hammer mill for comparative experiment. The products coming out were characterized by optical microscopy, SEM and liberation oriented leaching. Subsamples from the various EDF stages were inspected to investigate the progress of cracks and degree of copper layers exposure. The different energy levels used during the EDF processing have resulted in different degrees of PWBs damages, starting from components removal to entire structure perturbation and size reduction. EDF has resulted in generation of a lesser amount of fines, however the optimal approach in view energy efficient post-processing of the studied PWBs was the combination between single-stage EDF for components removal only with subsequent shredding of the depopulated boards. [less ▲]

Detailed reference viewed: 60 (15 ULg)
Full Text
Peer Reviewed
See detailElectro-assisted assembly of aliphatic thiol, dithiol and dithiocarboxylic acid monolayers on copper
Maho, Anthony ULg; Denayer, Jessica ULg; Delhalle, J. et al

in Electrochimica Acta (2011), 56(11), 3954-3962

Molecular assemblies of organothiol molecules on polycrystalline copper surfaces are a well known process to confer them specific organizational and protective properties. In this paper, an original and ... [more ▼]

Molecular assemblies of organothiol molecules on polycrystalline copper surfaces are a well known process to confer them specific organizational and protective properties. In this paper, an original and promising approach is considered through an electro-assisted adsorption process via a cathodic polarization of the copper substrate. Spectroscopic characterizations (PM-IRRAS, XPS) and electrochemical studies (CV, LSV, cathodic desorption, SECM) highlight and confirm the benefits brought by this methodology in terms of resulting SAMs features and considerable savings of preparation time. In addition to normal alkylthiols with a monopod anchoring group, alkyldithiocarboxylic acid and alkyldithiol monolayers - both bipodal - are characterized with the prospect of forming either easier to remove or more adherent films, respectively. © 2011 Elsevier Ltd. All rights reserved. [less ▲]

Detailed reference viewed: 36 (10 ULg)
Peer Reviewed
See detailElectro-assisted assembly of Aliphatic Thiol, Dithiol and Dithiocarboxylic Acid Monolayers on Polycrystalline Copper Substrates
Maho, Anthony ULg; Denayer, Jessica; Delhalle, Joseph et al

Conference (2011)

Detailed reference viewed: 6 (0 ULg)
Peer Reviewed
See detailElectro-assisted formation of organothiols self-assembled monolayers on polycrystalline copper surfaces
Maho, Anthony ULg; Denayer, Jessica; Delhalle, Joseph et al

Poster (2011)

Detailed reference viewed: 9 (1 ULg)
Full Text
See detailElectro-mechanical Coupling in MEMS: Modeling and Experimental Validation
Rochus, Véronique ULg; Golinval, Jean-Claude ULg

Scientific conference (2007)

This paper presents the advantages of a strong coupled formulation to model the electro-mechanical coupling appearing in MEMS. The classical modeling approach is to use a staggered methodology iterating ... [more ▼]

This paper presents the advantages of a strong coupled formulation to model the electro-mechanical coupling appearing in MEMS. The classical modeling approach is to use a staggered methodology iterating between two different programs to obtain the solution of the coupled problem. In this research a strong coupled formulation is proposed and a tangent stiffness matrix of the whole problem is computed. Using this matrix, nonlinear algorithms such as the Riks-Crisfield algorithm may be applied to solve the static nonlinear problem and accurately determine the static pull-in voltage. Moreover, the natural frequencies may be computed around each equilibrium positions. The dynamic behavior of the structure may also be studied and two new parameters are defined: the dynamic pull-in voltage and the dynamic pull-in time. This strong coupled methodology deriving from variational principle may also be used for topology optimization and extended finite elements. [less ▲]

Detailed reference viewed: 53 (4 ULg)
Full Text
Peer Reviewed
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

Detailed reference viewed: 22 (3 ULg)
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)

Detailed reference viewed: 14 (0 ULg)
Full Text
Peer Reviewed
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 ▲]

Detailed reference viewed: 12 (0 ULg)
Full Text
Peer Reviewed
See detailElectroanalytical Method Validation in Pharmaceutical Analysis and Their Applications
OZKAN, Sibel; KAUFFMANN, Jean-Michel; Rozet, Eric ULg et al

in Ozkan, Sibel Aysil; Kauffmann, Jean-Michel; Zuman, Petr (Eds.) Electroanalysis in Biomedical and Pharmaceutical Sciences : Voltammetry, Amperometry, Biosensors, Applications (2015)

Detailed reference viewed: 63 (4 ULg)