Search results for "Thermique"
showing 10 items of 40 documents
Contribution to the study and to the optimization of active thermographic process applied to surface crack detection
2017
The aim of this work is the detection of open and subjacent defects in metallic materials using laser-material interaction coupled with infrared thermography. This process is a possible alternative for magnetic particles testing and dye penetrant testing in the field of non-destructive testing. This work is divided into three main parties. At first, we have been interested in the characterization of optical and thermophysical properties of materials we used, in order to have good boundary conditions and also for the needs of temperatures fields measurements for validation. The second part concern the development of a numerical simulation model with two step approach: the first involves mode…
Determination of energy fluxes in composite plates or processed by Vico-constrained damping patch
2021
Lightening structures is an important issue in the world of transport. On the other hand, for the improvement of comfort, increasing performance is demanded today, particularly in the vibratory and acoustic field, which leads to the addition of damping materials. The proposed research work consists in the vibrational optimization of the structures by the addition of viscoelastic patches damping positioned wisely. The main function of the viscoelastic used to improve the vibro-acoustic performances, is to provide a mechanism of dissipation of mechanical energy. This attenuation of noise and vibrations causes a conversion of mechanical energy into thermal energy, which, after diffusion into t…
Study of the interactions and physicochemical properties of pea and egg white protein mixtures : from the colloidal to the gelled state.
2022
In recent years, due to the growth of world population, people's consumption of animal protein has increased, leading to the increase of greenhouse gas emissions and land occupation. Therefore, it is necessary to partially replace animal protein with vegetable protein to increase the proportion of vegetable protein in daily consumption and developing mixed food systems seems to be one adequate solution. Pea proteins as a source of plant proteins have good nutritional properties but with limited functional properties while egg white (EW) has good functional properties such as gelling and foaming. Thereby, the physicochemical interactions from mixtures of both types of protein needs to be und…
Interactions entre la beta-lactoglobuline et les arômes : impact au niveau moléculaire
2008
Interactions between β-lactoglobulin (BLG) and aroma compounds were investigated by complementary techniques for a better knowledge of binding mechanisms between proteins and aroma compounds at a molecular scale. Two binding sites have been defined for the monomeric BLG, one internal site within the central calyx, and one external site between the calyx and the α helix. In a first step, a relation between the ligand structure and its binding behaviour was established from the study of impact of a wide range of aroma compounds on the structure of native BLG. We evidenced at least two binding behaviours as a function of the chemical class, the hydrophobicity, or the structure of the ligands. …
Phases transitions in complexe oxides with perovskite structure : case system (1-x)Na0,5Bi0,5TiO3 - xCaTiO3
2015
The solid solutions (1-x)Na0,5Bi0,5TiO3 (NBT) – xCaTiO3 (CT) were studied by X-ray diffraction, Raman spectroscopy, scanning electron microscopy, impedance spectroscopy and DSC. These materials have a perovskite crystalline structure. This study reveals not only the complexity but also the richness of physical phenomena in these compounds: phases transitions sequences, the Ca2+ effect on the physical-chemistry properties and the relation between dielectric properties and crystalline structure. Thereby, (1-x)NBT – xCT solid solutions (0 ≤ x ≤ 1.00) were synthesized by chemical solid route, then they were sintered by a particular procedure in order to avoid sodium and bismuth volatilization. …
Representation of thermal building simulation in virtual reality for sustainable building
2014
The importance of energy efficiency as well as integration of advances in sustainable buildingdesign and VR technology have lead this research to focus on thermal simulation results visualized in avirtual environment (VE). The emphasis is on the representation of thermal building simulation (TBS)results and on the perception of thermal data simulated in a VE. The current application of the designprocess through energy efficiency in VR systems is limited mostly to building performance predictionsand design review, as the issue of the data formats and the workflow used for 3D modeling, thermalcalculation and VR visualization.Different applications and tools involved to represent TBS in VE are…
Integration of thermal building simulation and VR techniques for sustainable building projects
2013
Déjà présent sur HAL mais sans le fichier pdf; The importance of energy efficiency and integration of advances in building design and VR technology have led this research to focus on thermal simulation results visualized in a virtual environment to optimize building design. This paper combines the principle of integration for thermal calculation and scientific visualization in VR. The method is to use CAD models (extensively used in architectural design) to analyze a building's thermal performance and visualize it, as well as simulating it through VR technology. Interaction between users and objects in a virtual world are certainly through techniques of visualization metaphors. The object o…
Functional characterisation of the first HSP110 inhibitors.
2023
Heat shock proteins are molecular chaperones highly expressed in haematological malignancies. My laboratory has shown that the heat shock protein HSP110 is a new and important therapeutic target In colorectal cancer and in non-Hodgkin's lymphoma. As there were no existing inhibitors of HSP110, a screening strategy of a chemical library was carried out and allowed the identification of two molecules capable of specifically inhibiting the chaperone activity of HSP110. My thesis objective was to characterise and functionally validate these newly identified molecules in diffuse large cell B lymphomas. I have shown that one of these molecules limits the interaction of HSP110 with the SYK signall…
Water and temperature contribution to the structuration of starch matrices in the presence of flavour
2015
The effect of hydrothermal treatments and flavours addition on starch structure and its physical properties were studied. Native wheat starch was treated at 2 different hydrations (water-starch ratios: 50/50 and 80/20 g w/w) and temperatures (65 and 85 °C) in the presence of flavours (ethyl hexanoate and 2-hexanone). The freshly prepared samples were subjected to DSC and flavour analysis. Flavour inclusion complex could not be detected by DSC, however the result of flavour analysis proved that there were flavours interactions with starch. Both ethyl hexanoate and 2-hexanone interacted with starch at similar rates. The highest flavour loss was found in the samples at high hydration and heate…
Utilisation of natural carotenoids from Momordica cochinchinensis (gac) as health compounds : extraction and bioactvity depending on the origin and o…
2014
The aril of Momordica cochinchinensis (gac), plant from the Cucurbitaceae family, is the richest source of lycopene and β-carotene, which are a strong antioxidant and a pro-vitamin A, respectively, interesting for health-complements. First, a process of soft extraction-fractionation was developed for extracting effectively the natural carotenoids from gac without loss of their original quality. Then, the lycopene and β-carotene extracted from gac were analyzed and characterized. At least 95% of the extracts were composed of the all-trans isomer. They were not degraded during the heat-treatment mimicking formulation processing. Their thermal stereo-mutation was evaluated. Lycopene is more an…