University of Mons

About: University of Mons is a education organization based out in Mons, Belgium. It is known for research contribution in the topics: Large Hadron Collider & Standard Model. The organization has 3073 authors who have published 9465 publications receiving 294776 citations.

Observation of the associated production of a single top quark and a $W$ boson in $pp$ collisions at $\sqrt s = $8 TeV

Abstract: The first observation of the associated production of a single top quark and a W boson is presented. The analysis is based on a data set corresponding to an integrated luminosity of 12.2 fb^(−1) of proton-proton collisions at √s=8 TeV recorded by the CMS experiment at the LHC. Events with two leptons and a jet originating from a b quark are selected. A multivariate analysis based on kinematic and topological properties is used to separate the signal from the dominant tt background. An excess consistent with the signal hypothesis is observed, with a significance which corresponds to 6.1 standard deviations above a background-only hypothesis. The measured production cross section is 23.4±5.4 pb , in agreement with the standard model prediction.

Search for narrow resonances using the dijet mass spectrum in pp collisions at √s=8 TeV

Abstract: Results are presented of a search for the production of new particles decaying to pairs of partons (quarks, antiquarks, or gluons), in the dijet mass spectrum in proton-proton collisions at sqrt(s) = 8 TeV. The data sample corresponds to an integrated luminosity of 4.0 inverse femtobarns, collected with the CMS detector at the LHC in 2012. No significant evidence for narrow resonance production is observed. Upper limits are set at the 95% confidence level on the production cross section of hypothetical new particles decaying to quark-quark, quark-gluon, or gluon-gluon final states. These limits are then translated into lower limits on the masses of new resonances in specific scenarios of physics beyond the standard model. The limits reach up to 4.8 TeV, depending on the model, and extend previous exclusions from similar searches performed at lower collision energies. For the first time mass limits are set for the Randall-Sundrum graviton model in the dijet channel.

Nanoscale insight into the exfoliation mechanism of graphene with organic dyes: effect of charge, dipole and molecular structure

Abstract: We study the mechanism of surface adsorption of organic dyes on graphene, and successive exfoliation in water of these dye-functionalized graphene sheets A systematic, comparative study is performed on pyrenes functionalized with an increasing number of sulfonic groups By combining experimental and modeling investigations, we find an unambiguous correlation between the graphene–dye interaction energy, the molecular structure and the amount of graphene flakes solubilized The results obtained indicate that the molecular dipole is not important per se, but because it facilitates adsorption on graphene by a “sliding” mechanism of the molecule into the solvent layer, facilitating the lateral displacement of the water molecules collocated between the aromatic cores of the dye and graphene While a large dipole and molecular asymmetry promote the adsorption of the molecule on graphene, the stability and pH response of the suspensions obtained depend on colloidal stabilization, with no significant influence of molecular charging and dipole

Highly Regular Organization of Conjugated Polymer Chains via Block Copolymer Self-Assembly

Abstract: The microscopic organization in thin films of block copolymers containing either polyparaphenylene, or polyphenyleneethynylene rigid segments covalently bound to a flexible polydimethylsiloxane or polystyrene sequence was investigated. Atomic force microscopy and theoretical modeling based on molecular mechanics/molecular dynamics calculations were combined. The typical morphology obtained revealed the presence of bright elongated structures.

Room temperature responses of visible-light illuminated WO3 sensors to NO2 in sub-ppm range

Abstract: In this paper, the effects of visible-light illumination on sensing properties of tungsten trioxide (WO3) sensors have been investigated. WO3 sensitive films are prepared on alumina substrates by screen-printing. WO3 sensors illuminated by visible/ultra-violet lights are submitted to sensing tests with 160 and 320 ppb nitrogen dioxide (NO2) at room temperature. NO2 sensing characteristics of the WO3 sensor are significantly improved by illumination as compared to that in the dark. Influences of light wavelength and light intensity on the sensing characteristics are further studied. The results show that visible light can effectively activate the WO3 sensors and blue light is a good choice to produce room-temperature devices which are suited for NO2 sensing applications. A sensing mechanism is proposed according to a simple adsorption–photodesorption model.