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Discrétisation d’un gradient de température lors d’un déplacement liquide à travers un mélange solide
2018, HENALLUXFoRSArticle scientifiqueCet article montre comment discrétiser un gradient de température en tout point lors d’un échange de chaleur entre un liquide et un solide suite au déplacement forcé du premier dans le second. Le gradient de température obtenu permet de déterminer la température de chaque mélange liquide et solide à tout endroit d’un lessiveur de cuisson du bois afin d’établir le modèle énergétique d’un cycle ... -
Dissociative excitation of NeD+
2009, HENALLUXArticle scientifiqueMeasurements of NeD+ dissociative excitation cross section were obtained in Louvain-la-Neuve (UCL, Belgium) by using the animated crossed electron-ion beam method. The electronic structure of the system was calculated by using quantum chemistry calculations for the NeD+ ion and ab initio electron scattering calculations using the complex Kohn variational method for the resonant NeD neutral complex ... -
Electron impact dissociation of ND+: formation of D+
2011, HENALLUXArticle scientifiqueNitrogen is a common contaminant species in fusion reactors such as the ITER (International Thermonuclear Experimental Reactor). Thus, the collisional properties of nitrogen-containing plasma compounds arewidely studiedexperimentally andtheoretically. Here we show the results of absolute cross section measurements for the electron impact dissociative excitation of ND+ yielding D+, especially ... -
Electron impact dissociation of ND+: formation of D+
2011, HENALLUXArticle scientifiqueAbsolute cross sections for electron impact dissociation of ND+ leading to the formation of D+ have been measured by applying the animated electron-ion beam method in the energy range from the reaction threshold up to 2.5 keV. The maximum inclusive cross section is observed to be (16.8 ± 0.8) × 10−17 cm2 at the electron energy of 65.1 eV. The appearance energy for the D+ production is measured to ... -
Electron impact ionization of thymine clusters embedded in superfluid helium droplets
2007, HENALLUXArticle scientifiqueEmbedding molecules in helium clusters has become a powerful technique for the preparation of cold targets for spectroscopy experiments, as well as for the assembly of complex, fragile molecular species. We have recently developed a helium cluster source and a pick-up cell to produce neutral beams of doped helium droplets, to be used as targets in studies on electron collisions with molecules of ... -
Electron impact multiple ionization of argon ions
2010, HENALLUXArticle scientifiqueAbsolute cross sections for electron impact single and multiple ionization of argon ions leading to the formation of Ar q + (q = 2–8) are reported. The animated crossed beam method is applied in the energy range extending from the respective thresholds up to 2.5 keV. The maximum cross sections for the multiply charged products Ar q + (q = 2–8) are measured to be (12.6 ± 0.6) × 10−17 cm2 for Ar2+, ... -
Electron impact multiple ionization of C+ and N+ and O+ ions
2014, HENALLUXArticle scientifiqueAbsolute cross sections for electron impact single and multiple ionization of C+, N+ and O+ ions leading to the formation of Cq+ (q=2-4), Nq+ (q=2-5) and Oq+ (q=2-5) are reported in the energy range extending from the respective thresholds up to 2.5 keV. The general feature of the measured cross sections is investigated. -
Electron-impact dissociation and ionization of NH+: formation of N+ and N2+
2010, HENALLUXArticle scientifiqueAbsolute cross sections for electron-impact dissociation and ionization of NH+ leading to the formation of N+ and N2+ products have been measured by applying the animated electron–ion beam method, in the energy range from the respective thresholds up to 2.5 keV. The maximum total cross sections are observed to be (15.7 ± 0.7) × 10−17 cm2 and (11.1 ± 0.2) × 10−18 cm2 for N+ and N2+, respectively. ... -
Electron-impact dissociation and ionization of OH+ and OD+ ions
2012, HENALLUXArticle scientifiqueAbsolute cross sections for electron impact ionization and dissociation of OH+ and OD+ leading to the formation of the OH2+, O+, O2+, O3+ and D+ ions have been measured by applying the animated electron-ion beam method in the energy range from the respective reaction thresholds up to 2.5 keV. The maximum of the single ionization cross section is found to be (0.95±0.02) × 10−19 cm2 at 155 eV. ... -
Electron-impact dissociation of HeH+: absolute cross sections for the production of Heq+ (q = 1–2) fragments
2014, HENALLUXArticle scientifiqueAbsolute cross sections have been measured for electron-impact dissociative excitation and ionization of the helium-hydride ion (HeH+) leading to the formation of helium ions Heq+ (q = 1–2). Measurements have been performed for electron energies ranging from the respective thresholds up to 2.5 keV. For He+ production, the maximum absolute cross section for dissociative excitation is found to be (2.5 ... -
Electron-impact dissociative ionization of the molecular ion HDO + : A global view
2014, HENALLUXArticle scientifiqueWe present a combined experimental and theoretical study of the fragmentation of HDO2+ molecular ions produced by electron-impact ionization of HDO+ in the collision energy range 20–2500 eV. Experimental absolute partial inclusive cross sections for the production of OD+, OH+, and O+ are reported and compared successfully to theoretical predictions. Ab initio methods are used to calculate the ... -
Electron-impact ionization and dissociation of C2D+
2010, HENALLUXArticle scientifiqueAbsolute cross sections for electron-impact single ionization, dissociative excitation and dissociative ionization of the ethynyl radical ion (C2D+) have been measured for electron energies ranging from the corresponding reaction thresholds to 2.5 keV. The animated crossed electron-ion beam experiment is used and results have been obtained for the production of C2D2+, C2+, C+2, CD+, C+ and D+. The ... -
Electron-impact ionization of atomic hydrogen: dynamical variational treatment
2011, HENALLUXArticle scientifiqueA simple and straightforward calculating scheme is proposed for electron-impact single and multiple ionization of atoms. The method is based on the application of the Hulthén-Kohn dynamical variational principle. An effective charge seen by the scattered electron is determined for a certain type of trial wave functions mathematically in a rigorous way excluding any empirical assumptions. Validity ... -
Electron-impact ionization of singly-charged neon ions
2008, HENALLUXArticle scientifiqueAbsolute cross sections for electron-impact single and multiple ionization of Ne+ leading to the formation of Neq+ (q = 2–5) are reported. The animated crossed beams method is applied in the energy range from the respective thresholds up to 2.5 keV. The maximum cross sections are found to be (4.12 ± 0.21) × 10−17 cm2, (1.42 ± 0.07) × 1018 cm2, (2.57 ± 0.14) × 10−20 cm2, (8.78 ± 0.54) × 10−22 cm2 for ... -
Energy distributions of H+ fragments ejected by fast proton and electron projectiles in collision with H2O molecules
2009, HENALLUXArticle scientifiqueExperimental measurements of the kinetic energy distribution spectra of H + fragment ions released during radiolysis of water molecules in collision with 20, 50, and 100 keV proton projectiles and 35, 200, 400, and 1000 eV electron projectiles are reported using a pulsed beam and drift tube time-of-flight based velocity measuring technique. The spectra show that H + fragments carrying a ... -
Etude de faisabilité technique : conception d’un nouveau type d’hydrolienne
2016, HENALLUXFoRSArticle scientifiqueCet article traitre de l’étude de faisabilité technique, réalisée au centre de recherche FoRS, concernant la conception d’un moyen de production hydroélectrique pouvant être utilisé sur une faible hauteur de chute (de 1 à 2 m) avec un débit de cours d’eau allant de 0,4 à 1 m³/s pour une puissance escomptée entre 1 et 5 kW. Ce moyen de production est basé sur le principe d’une roue de type « Poncelet ». -
Etude de la propulsion d’un drone
2016, HENALLUXFoRSArticle scientifiqueCet article traite de la façon dont on peut dimensionner la propulsion d’un drone. Ce dimensionnement s’est fait avec les méthodes de Froude et Glau Glauert en ce qui concerne les hélices. -
Etude du risque de surchauffe dans une maison de repos à travers une simulation dynamique
2016, HENALLUXFoRSArticle scientifiqueLe bâtiment étudié est le projet d’une maison de repos à Neufchâteau, où l’isolation prévue est plus importante que dans un bâtiment dit traditionnel. Une simulation dynamique est donc nécessaire pour étudier son comportement et prévenir du risque de surchauffe. Sur base de ces résultats, des améliorations du confort sont proposées pour limiter la surchauffe. -
Etude d’une couche limite turbulente sous des gradients de pression variables
2011, HENALLUXFoRSArticle scientifiqueLe présent article décrit l’analyse d’une couche limite turbulente créée en soufflerie à la surface d’une plaque plane en plexiglas pour un flux d’air ayant un nombre de Reynolds Reθ compris entre 1900 et 3400, sous des conditions de dépression et de surpression. La variation de pression a été réalisée grâce à la contraction de la veine fluide dans laquelle les mesures ont été effectuées. Cet ... -
Etude et modification d’un four de trempe de verre lui donnant la capacité de tremper du verre de 3 mm d’épaisseur
2006, HENALLUXFoRSArticle scientifiqueL’étude consiste à apporter des modifications sur un four de trempe de verre dans le but de pouvoir tremper du verre de 3 mm d’épaisseur. Pour ce faire, il a fallu adapter un système additionnel d’air comprimé permettant de délivrer une plus grande pression et un plus grand débit d’air. Ainsi, la plage de trempe du four est passée d’une plage de 4 à 19 mm d’épaisseur à une plage de 3 à 19 mm ...