Search results for "CHIMIE"
showing 10 items of 170 documents
Controllable morphology of flux avalanches in microstructured superconductors
2014
The morphology of abrupt bursts of magnetic flux into superconducting films with engineered periodic pinning centers (antidots) has been investigated. Guided flux avalanches of thermomagnetic origin develop a tree-like structure, with the main trunk perpendicular to the borders of the sample, while secondary branches follow well-defi ned directions determined by the geometrical details of the underlying periodic pinning landscape. Strikingly, we demonstrate that in a superconductor with relatively weak random pinning, the morphology of such flux avalanches can be fully controlled by proper combinations of lattice symmetry and antidot geometry. Moreover, the resulting flux patterns can be re…
De l’ingénierie de protéines de liaison aux odorants à la détection électrochimique de molécules volatiles vers la conception de biocapteurs et nez é…
2014
The detection of odorant molecules has become an important challenge in different research area, such as the food industry, medical diagnostics and homeland security. Indeed, the thousands of odorants in our environment provide information on their chemical nature or their concentration. Human olfactory system is capable of discriminating thousands of different molecules thanks to biochemical mechanisms involving multiple protein receptor partners and a combinatorial coding. These biomolecules that include olfactory receptors and odorant-binding proteins (OBP) represent an interesting source of detectors for the design of biosensors. OBPs are small soluble proteins present in nasal mucus at…
PARI 2010-2011 - Projet DINOS "Innovinaroma" ou Mélanges d'odorants et milieux complexes
2011
L'idée est de réaliser une méta-analyse non ciblée de données d'origines multiples afin de prendre en compte à la fois les résultats de l'analyse sensorielle établie sur le concept de typicité mais aussi celles de l'olfactométrie séparative, de l'analyse semi-quantitative, de la chimie des odorants identifiés, de la psychophysique et de l'aromatique alimentaire. Le statut de composés clés porteurs de typicité aromatique, relève de leur présence en mélange dans des gammes de concentrations et dans un environnement à la fois complexe et diversifié propre à la catégorie sensorielle cible. Les approches, dont le but était de faire émerger un tel groupe d'odorants, jusqu'ici trop simplistes ou t…
Hexagonal Microparticles from Hierarchical Self-Organization of Chiral Trigonal Pd3L6 Macrotetracycles
2021
Construction of structurally complex architectures using inherently chiral, asymmetric, or multi-heterotopic ligands is a major challenge in metallosupramolecular chemistry. Moreover, the hierarchical self-organization of such complexes is unique. Here, we introduce a water-soluble, facially amphiphilic, amphoteric, chiral, asymmetric, and hetero-tritopic ligand derived from natural bile acid, ursodeoxycholic acid. We show that via the supramolecular transmetalation reaction, using nitrates of Cu(II) or Fe(III), and subsequently Pd(II), a superchiral Pd3L6 complex can be obtained. Even though several possible constitutional isomers of Pd3L6 could be formed, because of the ligand asymmetry a…
Applications of Quantum Chemistry in Spectroscopy: Molecules, Complexes of Van der Waals, trapped Molecules
2009
I described in this memory my activities as a researcher at Tomsk well before 2003, in succession to the State University of Tomsk in the Faculty of Physics, Institute of Physics of Siberia, and the Institute of 'Atmospheric Optics, in France since then, mostly at the University of Bourgogne (ICB), but also at the University of Lille I (PhLAM) and the University of Marne-la-Vallée (LCT). Part of my work has been dedicated to the evaluation by calculating ab initio of rovibrational constants for quasi-spherical molecules. The centrifugal distortion constants and the dipole moment of the molecule SO2F2 were calculated to validate the tensor theory and interpreter the spectrum. I twas shown th…
Acoustic wave guides as infinite-dimensional dynamical systems
2015
We prove the unique solvability, passivity/conservativity and some regularity results of two mathematical models for acoustic wave propagation in curved, variable diameter tubular structures of finite length. The first of the models is the generalised Webster's model that includes dissipation and curvature of the 1D waveguide. The second model is the scattering passive, boundary controlled wave equation on 3D waveguides. The two models are treated in an unified fashion so that the results on the wave equation reduce to the corresponding results of approximating Webster's model at the limit of vanishing waveguide intersection.
Caractérisation des céramiques à bioclastes de la Protohistoire dans l’ouest de la France.
2015
The study of the ceramics from the site of the Batterie Basse in the region of Manche, shows again that the presence of bioclasts in the clays of protohistoric ceramics is a very common phenomenon in Normandy unlike in Brittany, where in the current state of knowledge only one individual from the Iron Age has been described. These bioclasts, mostly fragments of bivalves, are non-plastic elements naturally present in the clays, either in the form of fossils, either in the form of contemporary shells, or are incorporated by the craftsmans after being pounded to modify the technical characteristics of the clays. The aim of this work is to awareness the archaeologists to this type of artefacts …
Caractérisation et diagenèse thermique des roches mères pétrolières de la série des Schistes d'âge néocomien moyen-barrémien dans le bassin intérieur…
2006
8 pages; International audience
Expression hétérologue, repliement in vitro et caractérisation biophysique du domaine N-terminal de la sous-unité T1R3 du récepteur humain au goût su…
2010
The sweet taste receptor is a heterodimer composed of two subunits called T1R2 and T1R3. Each subunit belongs to the class C of G protein-coupled receptors and is constituted by a large extracellular N-terminal domain (NTD) linked to the transmembrane domain by a cysteine-rich region. It has been shown that T1R2 and T1R3 NTDs are both able to bind natural sugars and sucralose with distinct affinities and undergo ligand-dependent conformational change (Nie et al., Curr Biol, 2005). However, the binding properties of T1R3 NTD and the relative contribution of the two subunits to the heterodimeric receptor function remained largely unknown. To characterize the binding properties of each subunit…
Contribution to the modeling of microstructural corrosion on aluminium alloys : definition of a methodology to study the bimetallic corrosion phenome…
2008
The initiation and the propagation of aluminum alloys microstructural corrosion is mainly based on the bimetallic corrosion phenomenon. This type of corrosion is caused by galvanic coupling at a local scale between the different phases contained in the alloy. The description of the localized corrosion phenomenon has been largely studied. Their complexity can explain why they are so difficult to predict by the way of numerical tools and why the works that have been done on this subject are so scarce. The present thesis brings a new contribution to this field by suggesting a methodology based on the complementary use of local electrochemical techniques and the finite element simulation of bim…