Temperature dependence of the static permittivity andintegral formula for the Kirkwood correlation factor ofsimple polar fluids

An exact integral formula for the Kirkwood correlation factor of isotropic polar fluids $g_K$ is derived from the equilibrium averaged rotational Dean equation, which as compared to previous approaches easily lends itself to further approximations. The static linear permittivity of polar fluids $\epsilon$ is calculated as a function of temperature, density and molecular dipole moment in vacuo for arbitrary pair interaction potentials. Then, using the Kirkwood superposition approximation for the three-body orientational distribution function, we suggest a simple way to construct model potentials of mean torques considering permanent and induced dipole moments. We successfully compare the theory with the experimental temperature dependence of the static linear permittivity of various polar fluids such as a series of linear monohydroxy alcohols, water, tributyl phosphate, acetonitrile, acetone, nitrobenzene and dimethyl sulfoxide, by fitting only one single parameter, which describes the induction to dipole-dipole energy strength ratio. We demonstrate that comparing the value of $g_K$ with unity in order to deduce the alignment state of permanent dipole pairs, as is currently done is in many situations, is a misleading oversimplification, while the correct alignment state is revealed when considering the proper interaction potential. Moreover we show, that picturing H-bonding polar fluids as polar molecules with permanent and induced dipole moments without invoking any specific H-bonding mechanism is in many cases sufficient to explain experimental data of the static dielectric constant. In this light, the failure of the theory to describe the experimental temperature dependence of the static dielectric constant of glycerol, a non-rigid polyalcohol, is not due to the lack of specific H-bonding mechanisms, but rather to an oversimplified model potential for that particular molecule

Le comportement délinquant de l'adolescent ivoirien (développement, facteurs et prévention)

Le comportement délinquant chez l'adolescent Ivoirien se développe en stades hiérarchiques (stades d'émergence, d'activation et d'aggravation) avec deux niveaux de désistement et se structure en comportements délinquants occasionnel, persistant léger et persistant grave. A chaque stade correspond un groupe de facteurs explicatifs, continus, spécifiques, en interaction et donc structurés hiérarchiquement et de manière discriminative: dysfonctionnements familial et social rapprochés, personnalité à risque et déclencheurs (primaires, secondaires et tertiaires). La régression de ces trois groupes de facteurs conduit aux deux niveaux de désistement. La prévention (à évaluer) porte sur l'émergence, les situations à risque délinquant et la persistance du comportement délinquant, le tout organisé autour d'une structure de réadaptation psychosociale. Enfin l'étude a abouti à la proposition d'un modèle, le modèle HIDSO (Hiérarchique, Interactionniste et Discriminatif autour du Sujet Organisateur).Ivorian adolescent delinquency behaviour expands in hierarchical stages (emergence, activation and aggravation stages) with two levels of withdrawal. It structures in delinquency behaviours: Occasional, light persistant and serious persistant. At each stage corresponds a group of explanatories factors, continuous, specifics, in interaction and so hierarchicaly structured and of a discriminatory way: connected social and family dysfunction; personality at risk and launchers (primaries, secondaries and tertiairies). Regression of these three groups of factors conduct at the two lewels of withdrawal. The prevention (for evaluation) concerns emergence, delinquency, situation at risk and delinquency behaviour persistant; The whole is organized about a structure of psychosocial readaptation. At last, this study conduct at a model proposition, HIDSO model (Hierarchical, Interactive and Discriminative about Organizer Subject).LYON2/BRON-BU (690292101) / SudocSudocFranceF

Changement de représentations de l'objet travail (le public précurseur des bilans de compétences)

Poussé par la mouvance d'un marché socio-économique en pleine mutation, le travail change. Il ne s'agit pas de simples aménagements de l'existant, mais réellement d'une crise sociétale et culturelle que notre pays, traverse, et qui pousse les individus à modifier leur représentation du travail. Si certains actifs résistent et souffrent de ces transformations obligées, un public particulier semble s'en accommoder, voire prendre les devants par la mise en acte de pratiques nouvelles et une image renouvelée de l'objet travail : les bénéficiaires de bilans de compétences. Cette étude, réalisée sur l'ensemble de la région Rhône-Alpes, montre en quoi les représentations sociales du travail ont entamé des " transvolutions " de nature irréversible, et comment les bénéficiaires de bilans de compétence ont déjà intégré ces mouvements dans leur sphère représentationnelle de l'objet concerné. Sous l'angle de la théorie du noyau central, cette thèse démontre que le travail n'est pas affecté dans ses éléments centraux, ancrage de l'identité singulière et sociale des individus, mais qu'il subit des modifications manifestes d'éléments périphériques stratégiques. Organisation hiérarchique, responsabilités, environnement, lien social, solidarité, autonomie, adaptabilité, formation, principales cibles de ces métamorphoses, s'accompagnent de valeurs et de pratiques en changement que les " bilantés " se sont appropriés, comparativement à un groupe témoin, et qui autorisent à les considérer comme des " précurseurs " de ce nouvel objet travail " transvolué ".LYON2/BRON-BU (690292101) / SudocSudocFranceF

Du vagabond au S.D.F. (place d'une matrice culturelle et historique dans le processus de formation des représentation sociales)

LYON2/BRON-BU (690292101) / SudocSudocFranceF

Groupes et société : initiation à la psychosociologie des groupes / Michel Cornaton,...

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Temperature dependence of the Kirkwood correlation factor and linear dielectric constant of simple isotropic polar fluids.

The theory developed in an accompanying paper [Déjardin, Phys. Rev. E 105, 024109 (2022)10.1103/PhysRevE.105.024109] is used to compute the Kirkwood correlation factor of simple polar fluids of different nature. From this calculation, the theoretical static permittivity is readily obtained, which is compared with experimental values. This is accomplished by fitting only one parameter accounting for induction or dispersion forces and torques, which is necessarily connected with the individual molecular polarizability but not explicitly related to the physical properties due to the nonadditivity of such energies. Excellent agreement between theoretical and experimental static permittivities is obtained over a very broad temperature range for a number of associated and nonassociated liquids. Finally, limitations of the present theory are given

The Thermochemistry of Alkyne Insertion into a Palladacycle Outlines the Solvation Conundrum in DFT

In an effort to determine the thermochemistry of established organometallic transformation, the well documented reaction of alkynes with a palladacycle was investigated by isothermal titration calorimetry (ITC). Although the mechanism of the insertion of unsaturated substrates into the Pd−C bond of cyclopalladated compounds is known, no information is available so far about their thermochemistry. The enthalpies of the reactions of Ph−C≡C−Ph and MeOC(O)−C≡C(O)COMe with the bisacetonitrilo salt of the N,N-benzylamine palladacycle were determined by ITC in chlorobenzene after having optimized the conditions to ensure that only the double and a single insertion of alkynes were occurring respectively. The reaction energy profile established by DFT for the double insertion process involving Ph−C≡C−Ph confirmed earlier conclusions on the rate determining character of the first insertion. Further computations of reaction enthalpies reveal significant discrepancies between ITC and DFT-D/continuum solvation enthalpies, that are suspected to arise from an unexpected explicit noncovalent interaction of PhCl with the components of the reaction