Protective clothing is widely used in many industries and applications to provide protection against fire exposure. Exposure to fire can result in skin burn injuries that range from first-degree to third-degree burn injury depending on the exposure intensity and duration. Within the firefighting community, and especially the petroleum and petrochemical industries flash fire is one of the possible fire hazards for workers. Exposure to flash fire is usually of short duration (a few seconds) until the worker runs away from the fire location. The typical protective clothing system consists of a fire resistant fabric, the human skin, and an air gap between the fabric and skin. The protective performance of the clothing is evaluated based on the total energy transfer from the fabric to the skin through the air gap causing burn injury to the skin. Therefore the air gap between the protective clothing and skin plays an important role in determining the protection level provided by the clothing since the energy transfer through the air gap determines the amount of energy received by the skin. The more realistic the analysis of the air gap, the more reliable the evaluation of the protective performance of the clothing. This study introduces a more realistic analysis for the air gap between protective clothing and the skin compared to that found in the literature. More specifically, the study accounts for the combined conduction-radiation heat transfer through the air gap, which was treated as a thermal radiation participating medium with temperature dependent thermophysical properties. A finite volume model was developed to simulate the transient heat transfer in a single layer protective clothing system with radiation heat transfer. The model was employed to investigate the influence of the conduction-radiation heat transfer through the air gap on the overall heat transfer through the protective clothing system and hence on its protective performance. The influence of different protective clothing parameters on the combined conduction-radiation heat transfer through the air gap such as the air gap absorption coefficient, air gap width, fabric thickness, and fabric backside emissivity was studied. A comprehensive study of the influence of a periodic variation in the air gap width and associated inflow of cool air due to the motion of the person wearing the clothing on its protective performance was carried out. A wide range of variation in the frequency and amplitude of the fabric periodic movement was considered to capture different scenarios for the wearers motion. Finally, a finite volume model was developed to simulate the transient heat transfer in multiple layers firefighters protective clothing. The model considered the combined conduction-radiation heat transfer in the air gaps entrapped between the clothing layers, which were treated as thermal radiation participating media. The influence of each air gap on the overall performance of the clothing was investigated as well. The improved air gap model is a significant improvement for modeling heat transfer in protective clothing. It was used to obtain a more detailed knowledge of the theoretical performance of such clothing, e.g. it was found that reducing the fabric backside emissivity was more effective in improving the clothing protective performance than increasing the fabric thickness. It was also observed that the motion of the person wearing the clothing has a significant effect on the performance of the clothing: an increase in the frequency of the fabric movement improves the protection provided by the clothing, primarily due to the more frequent inflow of cool air, while an increase in the amplitude of the fabric movement reduces the protection provided by the clothing by concentrating the exposure on the skin. Finally, the air gaps entrapped between the clothing layers in firefighters protective clothing were found to improve the clothing performance, and the influence of the air gap between the moisture barrier and the thermal liner is greater than that of the air gap between the outer shell and the moisture barrier.

Protective clothing is widely used in many industries and applications to provide protection against fire exposure. Exposure to fire can result in skin burn injuries that range from first-degree to third-degree burn injury depending on the exposure intensity and duration. Within the firefighting community, and especially the petroleum and petrochemical industries flash fire is one of the possible fire hazards for workers. Exposure to flash fire is usually of short duration (a few seconds) until the worker runs away from the fire location. The typical protective clothing system consists of a fire resistant fabric, the human skin, and an air gap between the fabric and skin. The protective performance of the clothing is evaluated based on the total energy transfer from the fabric to the skin through the air gap causing burn injury to the skin. Therefore the air gap between the protective clothing and skin plays an important role in determining the protection level provided by the clothing since the energy transfer through the air gap determines the amount of energy received by the skin. The more realistic the analysis of the air gap, the more reliable the evaluation of the protective performance of the clothing. This study introduces a more realistic analysis for the air gap between protective clothing and the skin compared to that found in the literature. More specifically, the study accounts for the combined conduction-radiation heat transfer through the air gap, which was treated as a thermal radiation participating medium with temperature dependent thermophysical properties. A finite volume model was developed to simulate the transient heat transfer in a single layer protective clothing system with radiation heat transfer. The model was employed to investigate the influence of the conduction-radiation heat transfer through the air gap on the overall heat transfer through the protective clothing system and hence on its protective performance. The influence of different protective clothing parameters on the combined conduction-radiation heat transfer through the air gap such as the air gap absorption coefficient, air gap width, fabric thickness, and fabric backside emissivity was studied. A comprehensive study of the influence of a periodic variation in the air gap width and associated inflow of cool air due to the motion of the person wearing the clothing on its protective performance was carried out. A wide range of variation in the frequency and amplitude of the fabric periodic movement was considered to capture different scenarios for the wearers motion. Finally, a finite volume model was developed to simulate the transient heat transfer in multiple layers firefighters protective clothing. The model considered the combined conduction-radiation heat transfer in the air gaps entrapped between the clothing layers, which were treated as thermal radiation participating media. The influence of each air gap on the overall performance of the clothing was investigated as well. The improved air gap model is a significant improvement for modeling heat transfer in protective clothing. It was used to obtain a more detailed knowledge of the theoretical performance of such clothing, e.g. it was found that reducing the fabric backside emissivity was more effective in improving the clothing protective performance than increasing the fabric thickness. It was also observed that the motion of the person wearing the clothing has a significant effect on the performance of the clothing: an increase in the frequency of the fabric movement improves the protection provided by the clothing, primarily due to the more frequent inflow of cool air, while an increase in the amplitude of the fabric movement reduces the protection provided by the clothing by concentrating the exposure on the skin. Finally, the air gaps entrapped between the clothing layers in firefighters protective clothing were found to improve the clothing performance, and the influence of the air gap between the moisture barrier and the thermal liner is greater than that of the air gap between the outer shell and the moisture barrier.

Les ylures de phosphore, employés comme catalyseur latent dans plusieurs réactions, trouvent aussi des applications dans des réactions d'intérêt biologique. Par exemple, leur utilisation dans des réactions de Wittig permet de synthétiser la vitamine A et d'autres caroténoïdes. Récemment, les ylures ont même été employés dans la réaction de Mitsunobu afin de remplacer le diéthylazodicarboxylate (DEAD). Le groupe du Professeur Benoît Marsan à l'UQÀM, qui développe depuis plusieurs années une cellule photovoltaïque électrochimique (CPE), s'est penché sur la réactivité des ylures de phosphore. Il a déjà été démontré, par voltampérométrie cyclique (VC), que la réduction électrochimique de certains sels de phosphonium mène à la formation de leur ylure correspondant. Ces comportements permettent de croire qu'il serait possible d'élaborer des couples redox organiques à partir de mélanges électrolytiques composés d'ylures de phosphore et de leur sel de phosphonium correspondant. La conception de nouveaux couples redox pour les CPEs et les cellules sensibilisées par un colorant, ou mieux connues sous le nom de piles de "type Gratzel", doit permettre l'amélioration de plusieurs points. Deux des principaux problèmes sont la faible conductivité ionique ainsi que la trop forte absorption de la lumière visible (empêchant celle-ci de se rendre à l'électrode photoactive) par le milieu électrolytique qui constitue l'une des composantes de la pile solaire qui limite son rendement de conversion d'énergie. Le système électrolytique ylure/sel pourrait grandement améliorer la conductivité ionique du milieu électrolytique, considérant la possibilité d'un échange de proton entre le sel et l'ylure, dont le mécanisme de migration de charges serait alors analogue au mécanisme de Grotthus dans l'eau. Dans le cadre de ce projet de maîtrise, des mélanges électrolytiques basés sur des ylures de phosphore (Ph₃PCHCN, Me₃PCHCN et Et₃PCHCN) en présence de leur sel de phosphonium correspondant ont été étudiés et comparés à des mélanges électrolytiques composés de phosphines (Ph₃P et Ph₂PCN), elles aussi en présence de leur sel de phosphonium. Tout d'abord, les ylures, les phosphines et les sels ont été synthétisés puis caractérisés chimiquement par spectroscopie RMN proton et phosphore. Par la suite, des mélanges ylure/sel et phosphine/sel de quelques compositions (rapports ylure ou phosphine/sel) ont été réalisés dans les solvants suivants: acétonitrile, éthylène carbonate-diméthylcarbonate en rapport molaire 1: 1 (EC-DMC) et le sel fondu à température ambiante bi((trifluorométhyl)sulfonyl)imide de 1-éthyl-3-méthylimidazolium (EMITFSI). Les résultats obtenus par spectroscopie d'impédance montrent que ces systèmes sont bien conducteurs (> 1 mS cm­­¯¹). Ces systèmes se sont avérés chimiquement et électrochimiquement stables sur une plage de température comprise entre 293 K et 353 K, en plus de présenter une faible coloration. Toutes ces propriétés sont recherchées pour améliorer la performance des systèmes électrolytiques, des CPEs et des piles de "type Grätzel". Les mesures de conductivité et de viscosité, ainsi que des expériences RMN ³¹p, ont permis de mieux comprendre les propriétés électrochimiques observées par VC. Cependant, il a aussi été démontré, par VC, que ces systèmes sont caractérisés par un mécanisme réactionnel irréversible ne permettant pas l'utilisation de ces mélanges en tant que couples redox. De plus, un mécanisme réactionnel associé aux réactions d'oxydation et de réduction observées par VC a été proposé dans ce travail. ______________________________________________________________________________ MOTS-CLÉS DE L’AUTEUR : Voltampérométrie cyclique, Ylures de phosphore, Conductivité, Piles solaires.

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Virtual three-dimensional (3D) auditory displays utilize signal-processing techniques to alter sounds presented through headphones so that they seem to originate from specific spatial locations around the listener. In some circumstances bone-conduction headsets (bonephones) can provide an alternative sound presentation mechanism. However, existing 3D audio rendering algorithms need to be adjusted to use bonephones rather than headphones. This study provided anchor points for a function of shift values that could be used to adapt virtual 3D auditory displays for use with bonephones. The shift values were established by having participants adjust phase and amplitude of two waves in order to cancel out the signal and thus produce silence. These adjustments occurred in a listening environment consisting of air-conducted and bone-conducted tones, as well as air- conducted masking. Performance in the calibration condition suggested that participants understood the task, and could do this task with reasonable accuracy. In the bone-to-air listening conditions, the data produced a clear set of anchor points for an amplitude shift function. The data did not reveal, however, anchor points for a phase shift function the data for phase were highly variable and inconsistent. Application of shifts, as well as future research to establish full functions and better understand phase are discussed, in addition to validation and follow-up studies.

Steel is the mother of industry, and is also an energy consumption intensive industry. Since the energy crisis, the various countries iron and steel plants positively take each energy frugal measure in order to reduce the fuel and the electric power consumption. In the iron and steel plant comparatively consumes the energy the system regulation equipment is the reheating furnace, so to save energy in a reheating furnace and reduce the energy consumption become one of important topics. The reduction consumes energy the countermeasure aspect may by analyze the heat transfer model and the change reheating furnace characteristic begins. In this thesis, we will build a simulation system of reheating furnace to analysis the temperature change of slab in a reheating furnace and discussion energy consumption factor. And then we use the thermal balance model to analysis the situation of fuel consumption. According to different conditions, we want to discuss the relationships energy consumption and increasing temperature of slab inside furnace.

Electrohydrodynamic (EHD) pumping of single and two-phase media is attractive for terrestrial and outer space applications since it is non-mechanical, lightweight, and involves no moving parts. In addition to pure pumping purposes, EHD pumps are also used for the enhancement of heat transfer, as an increase in mass transport often translates to an augmentation of the heat transfer. Applications, for example, include two-phase heat exchangers, heat pipes, and capillary pumping loops. In this research, EHD induction pumping of liquid film in annular horizontal and vertical configurations is investigated. A non-dimensional analytical model accounting for electric shear stress existing only at the liquid/vapor interface is developed for attraction and repulsion pumping modes. The effects of all involved parameters including the external load (i.e. pressure gradient) and gravitational force on the nondimensional interfacial velocity are presented. A non-dimensional stability analysis of EHD induction pumping of liquid film in a vertical annular configuration in the presence of external load for repulsion mode is carried out. A general non-dimensional stability criterion is presented. Stability maps are introduced allowing classification of pump operation as stable or unstable based on the input operating parameters. An advanced numerical model accounting for the charges induced throughout the bulk of the fluid due to the temperature gradient for EHD induction pumping of liquid film in a vertical annular configuration is derived. A non-dimensional parametric study including the effects of external load is carried out for different entrance temperature profiles and in the presence of Joule heating. Finally, a non-dimensional theoretical model is developed to investigate and to understand the EHD conduction phenomenon in electrode geometries capable of generating a net flow. It is shown that with minimal drag electrode design, the EHD conduction phenomenon is capable of providing a net flow. The theoretical model is further extended to study the effect of EHD conduction phenomenon for a two-phase flow (i.e. a stratified liquid/ vapor medium). The numerical results presented confirm the concept of liquid film net flow generation with the EHD conduction mechanism.

Thèse de doctorat : Science et ingénierie des matériaux : Vandoeuvre-les-Nancy, INPL : 2006. / Titre provenant de l'écran-titre. Bibliogr.

Thèse de doctorat : sciences. Matériaux : Ecully, Ecole centrale de Lyon : 2005. / 254 réf.

Thèse de doctorat : sciences. Matériaux : Ecully, Ecole centrale de Lyon : 2005. / Titre provenant de l'écran-titre. 254 réf.