Thesis (M.Sc.)--York University, 2005. Graduate Programme in Kinesiology and Health Science. / Typescript. Includes bibliographical references. Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://gateway.proquest.com/openurl?url%5Fver=Z39.88-2004&res%5Fdat=xri:pqdiss &rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft_dat=xri:pqdiss:MR11734

Th.--Sci. phys.--Grenoble--I.N.P., 1982. N°: DE 122.

A model has been developed for predicting turbulent heat transfer coefficients and associated temperature profiles in rough pipes from a knowledge of the fluid mechanics. The proposed method employs the Lyon heat transfer equation together with the velocity profile equations of Rouse and von Karman. Nusselt numbers were calculated by the proposed method for the following range of variables: f = fs to 0.020 Re = 4 x 10³ to 10⁷ Pr = 0.001 to 1,000 Temperature profiles were calculated for all combinations of the above extreme conditions, as well as for Pr = 1.0. The validity of the proposed model was tested by comparison of the predicted results with the experimental data of Nunner, Smith and Epstein and Dipprey. A similar test was made of Nunner's theoretical equation. It is concluded that, except for fluids with very low Prandtl numbers, e.g. liquid metals, the proposed model gives no better prediction of Nusselt number than Nunner's equation, which is less cumbersome to apply. In the existing form, the proposed model is not adequate. Certain combinations of the independent variables give rise to a discontinuity in the predicted value of Nusselt number. This is inconceivable in the physically real situation. Beyond the discontinuity appears a predicted region of zero net flow in the pipe. Two limiting assumptions can be made regarding the method of heat transport through this layer - viz. by molecular conduction only, or by an infinite conductivity eddy mechanism. Both assumptions have been made, and values of Nu calculated for each, whenever the situation arose. The agreement between the predicted and the experimental temperature profiles is in general good. However, not enough experimental data are available to satisfactorily define the effect of Re and f, and to substantiate the calculated results. / Applied Science, Faculty of / Chemical and Biological Engineering, Department of / Graduate

This study examined a new model of paclitaxel-induced neuropathic pain and the effects of systemic paclitaxel on the gap junction protein subunit Cx43 and potassium inwardly-rectifying channel Kir4.1 within the dorsal root ganglia. In the new neuropathic pain model, subplantar injections of paclitaxel resulted in decreased conduction velocities of A-beta fiber compound action potentials in the sciatic (5.9%) and tibial nerves (6.8%) as well as in M (10.6%) and H (10.2%) waves. By using repeated recordings it was found that following paclitaxel injection, conduction velocities in the contralateral plantar nerve increased (9.2%). Systemic injections of paclitaxel resulted in reduced Kir4.1 immunolabeling in the dorsal root ganglia compared to vehicle injections. This reduction was observed in total labeling (32.4%) as well as in areas of intense labeling (28.7%). Reductions in overall Cx43 immunolabeling (25%) and area (25%) following systemic paclitaxel injections were not statistically significant. The results of these studies suggest that subplantar injections of paclitaxel can result in reduced peripheral nerve conduction velocities. The results also show that a unilateral neuropathy can result in contralateral changes in conduction velocities. The effects of paclitaxel on reducing Kir4.1 levels suggest that neuropathic pain caused by paclitaxel may share mechanisms in common with other types of neuropathies which show similar changes in Kir4.1 levels.

This document only includes an excerpt of the corresponding thesis or dissertation. To request a digital scan of the full text, please contact the Ruth Lilly Medical Library's Interlibrary Loan Department (rlmlill@iu.edu).

The Clouds and the Earth's Radiant Energy System (CERES) is a program sponsored by the National Aeronautics and Space Administration (NASA) aimed at evaluating the global energy balance. Current scanning radiometers used for CERES consist of thin-film thermistor bolometers viewing the Earth through a Cassegrain telescope. The Thermal Radiation Group, a laboratory in the Department of Mechanical Engineering at Virginia Polytechnic Institute and State University, is currently studying a new sensor concept to replace the current bolometer: a thermopile thermal radiation detector. This next-generation detector would consist of a thermal sensor array made of thermocouple junction pairs, or thermopiles. The objective of the current research is to perform a thermal analysis of the thermopile. Numerical thermal models are particularly suited to solve problems for which temperature is the dominant mechanism of the operation of the device (through the thermoelectric effect), as well as for complex geometries composed of numerous different materials. Feasibility and design specifications are studied by developing a dynamic electrothermal model of the thermopile using the finite element method. A commercial finite element-modeling package, ALGOR, is used. / Master of Science

La membrane échangeuse de protons est un élément essentiel des piles à combustible. Elle permet le transfert des protons d’une électrode à l’autre pour produire de l’électricité. La conduction protonique des membranes actuelles est optimale vers 80°C et très sensible à l’eau. La conception de nouvelles membranes permettant le fonctionnement des piles à combustible à température ambiante et moins sensibles à l’eau est nécessaire. La solution proposée pendant ma thèse est de concevoir des microémulsions solidifiées conductrices de protons. Les microémulsions sont des mélanges liquides nanostructurés d’eau, d’huile et de tensioactifs à l’équilibre thermodynamique. Des microémulsions bicontinues, constituée de canaux d’eau et d’huile séparés par une monocouche de tensioactifs, formulées avec des tensioactifs conducteurs protoniques devraient avoir des propriétés intéressantes de conduction protonique. Il est ensuite nécessaire de solidifier les microémulsions obtenues pour pouvoir les utiliser comme membrane échangeuse de protons. Dans ce travail, la voie explorée consiste à utiliser une huile solide à température ambiante pour résoudre ce problème. Deux systèmes, contenant une huile solide à température ambiante et des tensioactifs conducteurs protoniques, ont été étudiés. Des microémulsions bicontinues sont ainsi préparées au-dessus du point de fusion de l’huile. Il s’agit ensuite de maîtriser comment un simple refroidissement permet d’obtenir des microémulsions solidifiées, matériaux solides avec la même structure que le liquide de départ. Cette étude a permis de mettre en évidence l’influence de la cristallisation sur la structure du matériau obtenu. / Proton-exchange membrane is an important part of fuel cells. It allows protons to move from one electrode to the other while producing energy. Proton conduction in current membranes is optimum at 80°C and very sensitive to water. It is therefore necessary to build new proton-exchange membranes to design fuel cells that are effective at ambient temperature and less water-sensitive.During my PhD, we intend to prepare solidified microemulsions as proton-exchange membranes. Microemulsions are nanostructured liquids composed of water, oil and surfactants at thermodynamic equilibrium. Bicontinuous microemulsions, made of water and oil channels separated by surfactants, obtained using proton conducting surfactants should have interesting proton conductivity. It is then necessary to solidify the obtained liquid to be able to use them as proton-exchange membrane. In this study, we use oil that is solid at room temperature to overcome this trouble. Two systems, with an oil solid at room temperature and proton-conducting surfactants, were studied. Bicontinuous microemulsions are prepared above the melting point of the oil. The point is then to understand how cooling down the liquid microemulsion allow to prepare a solidified microemulsion which is a solid with the same nanostructure as the initial liquid. This study highlights the influence of crystallization on nanostructure during cooling.

This report describes an experimental study of the conduction and absorption mechanisms of Germanium in the temperature range 4.2 - 1.5 K. The results of these studies were mainly devoted to the developments of very far infrared detectors. Germanium (Ge) is a well-known semiconductor element used widely, when doped with small concentration of impurities, for detection of far infrared wavelengths up to 100~m. For doping concentrations less 16 3 than 1.0 x 10 atoms/em, the absorption of radiation in the range 100- 1000~m is very weak Because of the lack of the proper absorption mechanisms, except for some photo-hopping absorption in compensated samples around 1000llm.16 -3 In the range of doping between 1-8 x 10 cm ,there exists additional thermal activation energy not present in the lower concentrations. It was thought that this activation energy results from impurity interactions in this doping range, and hence a delocalized energy band is thus formed above the ground state level. However, the electrical conduction, the width of this band and its position, and the relevance of this band to the marked bolometric effect for 10o-lOOOWU wavelength detections are not yet clear. This thesis presents further study on this band together with its relation to the conduction and absorption mechanisms. Comparative studies were usually made for two samples of Ge differing in doping configuration, one of which does not have this additional activation energy (low concentration) . The firs two chapters give a review of the absorption and conduction mechanisms in Ge at low temperatures, and the performance relations and measurements for different types of infrared detectors. In this report, the conduction mechanism is studied for the two samples, and includes galvanometric properties, thermal properties and energy scattering processes for the carriers in the delocalized band. The absorption characteristics, 1n lOO-lOOO~ru range of the two samples were investigated. Germanium elements with absorbing surfaces are also studied using two different techniques, namely, surface ion implantation and metal film deposition. The mutual effects of the implanted surface and the bulk material are discussed and suggestions for the future of this technique are given. Finally, the design and performance of the constructed high sensitivity far infrared Ge detectors using the higher concentration sample are given. Theoretical noise limitations were reached in these detectors. Heasurements and practicaI. astronomical applications are also given.

L'objectif de ces recherches est l'amélioration du procédé de placement de fibre par dépose laser, appliqué à des composites Poly(EtherKetoneKetone) / fibre carbone continue. L'optimisation des paramètres de dépose implique l'étude de la stabilité de la matrice, ainsi que l'analyse du comportement thermique des composites. La conductivité et diffusivité thermiques, ainsi que l'émissivité sont les paramètres clés pour comprendre le comportement des transferts volumiques et surfacique dans ces matériaux. Des composites PEKK/particules de carbone ont été élaborés afin d'étudier l'effet de la morphologie du carbone sur les paramètres thermiques. L'émissivité des composites PEKK / fibres continues a été mesurée en comparant les radiations émises par le matériau et celle émises par un corps noir à la même température. La conductivité et la diffusivité thermiques, qui sont des paramètres intrinsèques au composite, augmentent avec le taux de charge et la température. Ces deux paramètres ont été étudiés en fonction de la Température, dans le cas de composite PEKK / fibre carbone continue et PEKK / particules de carbone pour plusieurs taux de charge. / : The aim of this research is the improvement of the laser depositing fiber placement process, applied to Poly (EtherKetoneKetone) / continuous carbon fiber composites. The optimization of deposit parameters implies the investigation of the stability of the matrix and of the thermal behavior of composites. Thermal conductivity, diffusivity, and optical emissivity, are the key parameters for understanding the behavior of volume and surface conduction of composites. PEKK / carbon particle composites have been processed to study the effect of carbon morphology on thermal parameters. The emissivity of the PEKK / continuous fiber composites was measured by comparing the radiation emitted by the material with the one emitted by a black body at the same temperature. Thermal conductivity and diffusivity, which are intrinsic parameters of the composite, increase with the rate of charge and the temperature. These two parameters have been studied as a function of temperature, in the case of PEEK / continuous fibers composites and PEKK / carbon particles composites for various charge rates.

The problem solved in this thesis is one of transient linear heat conduction in a two layer, three-dimensional slab subjected to an arbitrary heat flux on one surface, where each layer is thermally orthotropic. The sides and bottom of the slab are either insulated (Bi = 0) or held at a constant temperature (Bi = infinity). The Biot number of the top surface varies from zero to infinity. The solution is developed by decomposing the problem into a number of simpler problems, each of which is solved using eigenfunction expansions. In the vertical direction, the eigenvalue problem is solved using the Krawczyk algorithm, and an orthogonality relationship is found by Vodicka's method.