Search results for "Propriété"
showing 10 items of 153 documents
Study of relationships between the structure of aroma compounds and their retention-release between vapour phase and dairy gels
2010
An integrated approach physicochemistry and structures activity relationships has been carried out to study the aroma compounds retention-release phenomenon in a fat free dairy gel added with pectin. This study aimed to identify the molecular properties that govern this phenomenon assuming that modifying the structure leads automatically to a change in the retention-release of aroma compounds. For this purpose, we have determined the partition coefficients of 28 aroma compounds in water, in pectin gels and in dairy gels supplemented or not supplemented with pectin, at equilibrium conditions using the PRV method (Phase Ratio Variation). Then, we have performed a structure-retention relations…
Structures de déformation induites par surpressions de fluide dans les environnements sous-glaciaires et marin profonds : implications paléoenvironne…
2014
Soft-sediment deformation structures (SSDs) occur in unconsolidated sediments, during or shortly after deposition. SSDs are abundant in subglacial and deep-marine environments because of the development of fluid overpressure. Case studies of these two sedimentary environments were used (1) to reconstruct palaeoenvironments from SSDS, and (2) to define the impacts of SSDS on glacial morphologies and (3) petrophysical properties.(1) Analyses of strain regimes, deformation mechanisms, and chronologies in SSDs served to improve palaeoenvironmental reconstructions. These structures were used as proxys to estimate variations of ice flow velocities, ice thickness, meltwater production, and positio…
Effects of garlic powders with varying alliin contents on hepatic drug metabolizing enzymes in rats
2003
International audience; The anticarcinogenic effect of garlic has been demonstrated in both epidemiologic and experimental studies. In this study, possible mechanisms involved in the anticarcinogenic effect of garlic consumption were assessed by determining its capacity to alter drug metabolizing enzymes, in relation with its alliin content. Rats were fed a diet for 2 weeks containing 5% garlic powders produced from bulbs grown on soils with different levels of sulfate fertilization and therefore containing differing amounts of alliin. Activities of several hepatic enzymes, which are important in carcinogen metabolism such cytochromes P450 (CYP) and phase II enzymes, were determined. Garlic…
Dynamic composition of services : application to designing and developping information systems in a distributed environment
2010
The service oriented computing paradigm plays an increasingly important role in structuring complex systems. Application design and development approaches are witnessing a shift from traditional models towards a more dynamic service oriented model promoting reuse and adaptability. In this thesis, we study an approach for application design and development based on services’ composition. We propose DyCoSe, an environment for sharing services. It consists of an enterprise ecosystem wherein members, organized in communities, share a global agreement describing traditional business functionalities and common non-functional properties. DyCoSe relies on a three level architecture for service base…
The Institutionalization of Political Risk Assessment by Chinese Multinational Firms
2021
Some researchers have claimed that Chinese firms are impervious to political risk, calling into question the institutionalization of political risk by Chinese firms. Building on resource dependence theory and the literature on non-market strategies, this study finds significant impact by ownership structure, firm scale, and the degree of internationalization on the institutionalization of political risk assessments (IPRA) by Chinese firms. As such, state-owned firms and larger firms cultivate a higher level of IPRA. We find a positive impact of a firm’s scale and scope of internationalization, but insignificant impact of depth of internationalization.
Synthesis of molecular materials and heterojunctions, on the interest of ambipolar materials in conductometric gas sensors
2017
The molecular semiconductors have enabled the production of electronic devices such as field effect transistors, diodes and other heterojunctions. The ambipolar materials, capable of carrying both positive charges and negative, result in devices with special properties. The purpose of this thesis is to synthesize new ambipolar materials develop original electronic devices, especially for applications in the field of gas sensors. We are interested in molecules capable to lead to thin films with low temperature techniques known as solution processing, particularly metallo-phthalocyanines.
L'influence des facteurs institutionnels sur la politique d'information financière des entreprises. Une analyse à la lumière du cas français
2009
International audience; L'influence des facteurs institutionnels sur la politique d'information financière des entreprises. Une analyse à la lumière du cas français.
Biomechanics of human ascending aorta and aneurysm rupture risk assessment
2021
Ascending aortic aneurysms (AsAA) and aortic dissections are life-threatening cardiovascular diseases. The main criteria for determining surgical intervention of AsAA are the maximum diameter or the increasing annual rate of the aneurysm. The mortality of the untreated aortic dissection can be 21% to 74%, depending on the delay of hospital admission.Our study aims to characterize the biomechanical properties of the ascending aorta and propose a patient-specific approach to assess the risks of rupture. The purpose of this PhD work is multifold.On the one hand, biaxial tensile tests were performed on AsAA samples obtained from one hundred patients with surgery of AsAA. The impact on the diffe…
Prédiction du comportement mécanique et étude de l’endommagement d’un composite tressé 3D par une analyse multiéchelle. Application à la conception d…
2014
Cette étude porte sur la prédiction du comportement mécanique et l’étude de l’endommagement de composites tressés 3D, utilisés pour fabriquer des réservoirs multiformes. D’une part, on cherche à prédire les propriétés effectives du matériau homogénéisé par une approche dite d’homogénéisation multiéchelle à partir de la connaissance des propriétés des constituants, de leur fraction volumique et de leur disposition au sein d’un élément de volume représentatif du matériau hétérogène communément appelé volume élémentaire représentatif (VER). D’autre part, on cherche à avoir accès à des grandeurs locales pour mieux comprendre les mécanismes d’endommagement identifiés expérimentalement et évaluer…
Elaboration de matériaux à gradient de propriétés fonctionnelles pour les composants face au plasma des machines de fusion thermonucléaires
2014
The objective of this study was to develop a Functionally Graded Material (FGM) W / Cu to replace the compliance layer (Cu-OFHC) in the plasma facing components of thermonuclear fusion reactor like ITER. The peculiarity of this work is to elaborate these materials without exceeding the melting temperature of copper in order to control its microstructure. The co-sintering is the most attractive solution to achieve this goal.The first phase of this study has been to decrease the sintering temperature of the tungsten to achieve this co-sintering. The elaboration of a Functionally Graded Materials being delicate, thermo-mechanical calculations were performed in order to determine the number and…