Delbecq, Françoise

Céline Dion : l'ascension d'une étoile by Françoise Delbecq( Book )

5 editions published in 1997 in French and held by 23 WorldCat member libraries worldwide

La biographie de la chanteuse canadienne qui, à moins de 30 ans, est devenue une superstar mondiale qui vend des millions de disques. Une success story racontée documents et témoignages à l'appui

ETUDE THEORIQUE DU MECANISME DE LA REDUCTION ASYMETRIQUE DES CARBONYLES PAR TRANSFERT D'HYDROGENE CATALYSEE PAR UN COMPLEXE DU RHODIUM(I) by Vincent Guiral( Book )

2 editions published in 2000 in French and held by 2 WorldCat member libraries worldwide

NOUS AVONS MENE UNE APPROCHE DE CHIMIE THEORIQUE (DFT AU NIVEAU GGA) AFIN DE DETERMINER LE MECANISME DE LA REDUCTION ASYMETRIQUE DES CARBONYLES PAR TRANSFERT D'HYDROGENE CATALYSEE PAR UN COMPLEXE DU RHODIUM (I) PORTANT DES LIGANDS AZOTES. TOUT D'ABORD, NOUS AVONS DETERMINE LA STRUCTURE DU COMPLEXE HYDRURE SUPPOSE ACTIF. IL S'AGIT D'UN COMPLEXE DE GEOMETRIE BIPYRAMIDE TRIGONALE COMPORTANT UNE SEULE DIAMINE ET UN CYCLOOCTADIENE (PROVENANT DU PRECURSEUR METALLIQUE). NOUS AVONS ALORS ETUDIE CINQ CYCLES CATALYTIQUES. UN SEUL EST ENANTIOSELECTIF. IL S'AGIT DU TRANSFERT CONCERTE DE L'HYDRURE ET D'UN PROTON DE LA DIAMINE RESPECTIVEMENT SUR LE CARBONE ET L'OXYGENE DU CARBONYLE. C'EST AUSSI LE MECANISME DONT L'ETAPE LIMITANTE A LA PLUS FAIBLE ENERGIE D'ACTIVATION. AVEC UNE DIAMINE CHIRALE, LA DIFFERENCE D'ENERGIE D'ACTIVATION ENTRE ETATS DE TRANSITION DIASTEREOISOMERES PERMET D'EXPLIQUER L'ENANTIOSELECTIVITE OBSERVEE EXPERIMENTALEMENT. LE MECANISME ADDITION-INSERTION A PARTIR DE L'HYDRURE ET LE MECANISME CONCERTE A PARTIR D'UN ALKOXY-COMPLEXE SONT POSSIBLES (LES BARRIERES SONT RAISONNABLES), MAIS, ILS NE SONT PAS ENANTIOSELECTIFS. ILS PEUVENT ETRE ENVISAGES DANS LE CAS OU LES LIGANDS SONT DES AMINES TERTIAIRES

Heterogeneous Transformation of Glycerol to Lactic Acid by Florian Auneau( )

1 edition published in 2012 in English and held by 2 WorldCat member libraries worldwide

Gamma-alumina: An Active Support to Obtain Immobilized Electron Poor Zr Complexes by Jérôme Joubert( )

1 edition published in 2008 in English and held by 2 WorldCat member libraries worldwide

Céline : l'ascension d'une étoile by Françoise Delbecq( Book )

1 edition published in 1997 in French and held by 1 WorldCat member library worldwide

Hybrid molecular simulations of oxidative complex lesions by Chandan Patel( )

2 editions published in 2013 in English and held by 1 WorldCat member library worldwide

DNA is continuously exposed to a vast number of damaging events triggered by endogenous and exogenous agents. Numerous experimental studies have provided key information regarding structural properties of some of the DNA lesions and their repair. However, they lack in mechanistic or energetic information pertaining to their formation. Computational Biochemistry has emerged as a powerful tool to understand biochemical reactions and electronic properties of large systems.In this thesis we study the formation of inter- and intra-strand cross-links. These tandem lesions pose a potent threat to genome integrity, because of their high mutagenic frequency. First, we discuss the formation of complex defects which arise from the attack of a pyrimidine radical onto guanine. In comparison with the reactivity of isolated nucleobases, our hybrid Car-Parrinello Molecular Dynamics simulations reveal that the reactivity of hydrogen-abstracted thymine and cytosine is reversed within a B-helix environment. Further, our data also suggest a more severe distortion of the B-helix for G[8-5]C.Second, we rationalize the higher reactivity of cytosine vs. purines toward the multistep formation of inter-strand crosslinks with a C4' oxidized a basic site, which is in qualitative agreement with experiments on isolated nucleobases, using explicit solvent simulations combined to density functional theory

Espaces( )

1 edition published in 1990 in French and held by 1 WorldCat member library worldwide

Approche combinée théorie-expérience pour la catalyse d'hydrogénation asymétrique by Asma Aloui( )

1 edition published in 2010 in French and held by 1 WorldCat member library worldwide

Several studies brought back the influence of the hydrogen pressure, more precisely the real hydrogen concentration dissolved in solution, on the enantioselectivity of the catalytic asymmetric hydrogenation for rhodium based catalysts. However to identify the enantiodetermining step(s), and to gain some further understanding on the hydrogen pressure-enantioselectivity relationship, the determination of the kinetic constants is required. We have thus embarked a project aiming such determination by coupling experimental work and theoretical chemistry. Two studies were undertaken on the asymmetric hydrogenation of both substrates by the Rh (I)/ (R,R)-Me-bpe catalyst. The experimental kinetic work study is based on the kinetic model suggested by Halpern in order to estimate the parameters kinetic of each elementary step, whereas that theoretical, consists in studying the various possible pathways by DFT calculation using the software of modelling Gaussian 03. The analysis of the obtained results made it possible to revisit the concepts' key of the catalytic asymmetric hydrogenation and to hold a discussion about the reliability of the theoretical methods to envisage the experiment