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.

Learning the parameters of a multiple criteria sorting method

Abstract: Multicriteria sorting methods aim at assigning alternatives to one of the predefined ordered categories. We consider a sorting method in which categories are defined by profiles separating consecutive categories. An alternative a is assigned to the lowest category for which a is at least as good as the lower profile of this category, for a majority of weighted criteria. This method, that we call MR-Sort, corresponds to a simplified version of ELECTRE Tri. To elicit the values for the profiles and weights, we consider a learning procedure. This procedure relies on a set of known assignment examples to find parameters compatible with these assignments. This is done using mathematical programming techniques. The focus of this study is experimental. In order to test the mathematical formulation and the parameters learning method, we generate random samples of simulated alternatives. We perform experiments in view of answering the following questions: (a) assuming the learning set is generated using a MR-Sort model, is the learning method able to restore the original sorting model? (b) is the learning method able to do so even when the learning set contains errors? (c) is MR-Sort model able to represent a learning set generated with another sorting method, i.e. can the models be discriminated on an empirical basis?

Spin asymmetry in muon-proton deep inelastic scattering on a transversely-polarized target

Abstract: The covalent functionalization of exfoliated semiconducting MoS2 by 1,2-dithiolanes bearing an ethylene glycol alkyl chain terminated to a butoxycarbonyl-protected amine and a photoactive pyrene moiety is accomplished. The MoS2-based nanohybrids were fully characterized by complementary spectroscopic, thermal, and microscopy techniques. Markedly, density functional theoretical studies combined with X-ray photoelectron spectroscopy analysis demonstrate preferential edge functionalization, primarily via sulfur addition along partially sulfur saturated zig-zag MoS2 molybdenum-edges, preserving intact the 2D basal structure of functionalized MoS2-based nanohybrids as confirmed by high-resolution transmission electron microscopy and electron energy loss spectroscopy. Furthermore, in the MoS2-pyrene hybrid, appreciable electronic interactions at the excited state between the photoactive pyrene and the semiconducting MoS2 were revealed as inferred by steady-state and time-resolved photoluminescence spectroscopy, implying its high potentiality to function in energy conversion schemes. MoS2 can be chemically functionalized with organic functional units, to develop innovative hybrid materials suitable for energy conversion. Collaborative efforts between experimental and modeling teams at the Theoretical and Physical Chemistry Institute—National Hellenic Research Foundation, Greece, Institut des Materiaux Jean Rouxel—CNRS Nantes, France, Instituto de Nanociencia, Universidad de Zaragoza, Spain, and Chimie des Interactions Plasma-Surface, University of Mons, Belgium, reveal that chemical functionalization occurs preferentially on MoS2 edge sites. When photoactive components are attached to MoS2 edges, visible light illumination promotes efficient charge transfer within the hybrid material. Research along those lines may result in the construction of innovative solar and photoelectrochemical cells with high efficiencies.

Functionalization of MoS 2 with 1,2-dithiolanes: toward donor-acceptor nanohybrids for energy conversion

Abstract: The covalent functionalization of exfoliated semiconducting MoS2 by 1,2-dithiolanes bearing an ethylene glycol alkyl chain terminated to a butoxycarbonyl-protected amine and a photoactive pyrene moiety is accomplished. The MoS2-based nanohybrids were fully characterized by complementary spectroscopic, thermal, and microscopy techniques. Markedly, density functional theoretical studies combined with X-ray photoelectron spectroscopy analysis demonstrate preferential edge functionalization, primarily via sulfur addition along partially sulfur saturated zig-zag MoS2 molybdenum-edges, preserving intact the 2D basal structure of functionalized MoS2-based nanohybrids as confirmed by high-resolution transmission electron microscopy and electron energy loss spectroscopy. Furthermore, in the MoS2-pyrene hybrid, appreciable electronic interactions at the excited state between the photoactive pyrene and the semiconducting MoS2 were revealed as inferred by steady-state and time-resolved photoluminescence spectroscopy, implying its high potentiality to function in energy conversion schemes. MoS2 can be chemically functionalized with organic functional units, to develop innovative hybrid materials suitable for energy conversion. Collaborative efforts between experimental and modeling teams at the Theoretical and Physical Chemistry Institute—National Hellenic Research Foundation, Greece, Institut des Materiaux Jean Rouxel—CNRS Nantes, France, Instituto de Nanociencia, Universidad de Zaragoza, Spain, and Chimie des Interactions Plasma-Surface, University of Mons, Belgium, reveal that chemical functionalization occurs preferentially on MoS2 edge sites. When photoactive components are attached to MoS2 edges, visible light illumination promotes efficient charge transfer within the hybrid material. Research along those lines may result in the construction of innovative solar and photoelectrochemical cells with high efficiencies.

Polarized spectral combs probe optical fiber surface plasmons.

Abstract: The high-order cladding modes of conventional single mode fiber come in semi-degenerate pairs corresponding to mostly radially or mostly azimuthally polarized light. Using tilted fiber Bragg gratings to excite these mode families separately, we show how plasmonic coupling to a thin gold coating on the surface of the fiber modifies the effective indices of the modes differently according to polarization and to mode order. In particular, we show the existence of a single “apolarized” grating resonance, with equal effective index for all input polarization states. This special resonance provides direct evidence of the excitation of a surface plasmon on the metal surface but also an absolute wavelength reference that allows for the precise localization of the most sensitive resonances in refractometric and biochemical sensing applications. Two plasmon interrogation methods are proposed, based on wavelength and amplitude measurements. Finally, we use a biotin-streptavidin biomolecular recognition experiment to demonstrate that differential spectral transmission measurements of a fine comb of cladding mode resonances in the vicinity of the apolarized resonance provide the most accurate method to extract information from plasmon-assisted Tilted fiber Bragg gratings, down to pM concentrations and at least 10−5 refractive index changes.