Many applications in microelectromechanical systems such as smart living space sensing system, microchannel system on chip and biomedical sensing system usually require instantaneously compensating or controlling the temperature of chip to acquire more linear and accurate output signal. So it is necessary to develop a micro temperature sensor or micro-hot-plate which has highly thermal isolation and low power characteristics. This thesis aims to design and fabricate a low power micro-hot-plate and a high-sensitivity temperature sensor for portable applications. This dissertation utilized a high power E-beam evaporator to deposit the platinum thin film as the material of temperature sensing and heating. The Pt layer is patterned using the lift-off technique. In addition, the micro-hot-plate can be released from the silicon substrate as a floating thin-plate using TMAH-based anisotropic etching technology. The floating structure can improve the thermal isolation and reduce the power loss through the silicon substrate. In this study, the higher temperature sensitivity (1914 ppm/¢J) and optimized sensing linearity ( > 99.9 %) of the platinum-based temperature sensor is demonstrated. On the other hand, the heating power of the floating micro-hot-plate developed in this research is only 14 mW when it be heated to 300 ¢J and the power efficiency is very high (18.3 ¢J/mW).

abstract: The current method of measuring thermal conductivity requires flat plates. For most common civil engineering materials, creating or extracting such samples is difficult. A prototype thermal conductivity experiment had been developed at Arizona State University (ASU) to test cylindrical specimens but proved difficult for repeated testing. In this study, enhancements to both testing methods were made. Additionally, test results of cylindrical testing were correlated with the results from identical materials tested by the Guarded Hot&ndashPlate; method, which uses flat plate specimens. In validating the enhancements made to the Guarded Hot&ndashPlate; and Cylindrical Specimen methods, 23 tests were ran on five different materials. The percent difference shown for the Guarded Hot&ndashPlate; method was less than 1%. This gives strong evidence that the enhanced Guarded Hot-Plate apparatus in itself is now more accurate for measuring thermal conductivity. The correlation between the thermal conductivity values of the Guarded Hot&ndashPlate; to those of the enhanced Cylindrical Specimen method was excellent. The conventional concrete mixture, due to much higher thermal conductivity values compared to the other mixtures, yielded a P&ndashvalue; of 0.600 which provided confidence in the performance of the enhanced Cylindrical Specimen Apparatus. Several recommendations were made for the future implementation of both test methods. The work in this study fulfills the research community and industry desire for a more streamlined, cost effective, and inexpensive means to determine the thermal conductivity of various civil engineering materials. / Dissertation/Thesis / M.S. Civil and Environmental Engineering 2011

This thesis deals with issues of used hot plates and thick-film technology. The theoretical part of diploma thesis contains a theoretical analysis and description of corresponding technology and usage of materials. The practical part of the thesis focuses on the design of the resulting device, which forms design of the test and optimized hot element, the initial design of the device and the design of models for temperature simulations. Then follows description of the practical realization of the motifs and testing of the created thick-film structure on a ceramic substrate. In the last part are shown simulations of heat transfer in the proposed model of the device.

INTRODUCTION: Smoking is one of the single greatest causes of numerous preventable diseases. We were interested in developing an animal model of nicotine metabolism that can be used to examine the effects of potential CYP2A6 inhibitors on nicotine metabolism and nicotine-mediated behaviours. Pharmacogenetic studies have demonstrated that in humans, smoking behaviour is associated with rates of nicotine metabolism by the CYP2A6 enzyme. Mouse CYP2A5 shares structural and functional similarities to human CYP2A6 and has been implicated in nicotine self-administration behaviours in mice, therefore the mouse represents a potential animal model for studying nicotine metabolism. METHODS: We characterized nicotine and cotinine metabolism in two commonly used mouse strains (DBA/2 and C57Bl/6). We also examined the association between nicotine self-administration behaviours and nicotine metabolism, and the impact of direct manipulation (i.e. inhibition) of nicotine metabolism on nicotine pharmacodynamics (hot-plate and tail-flick tests) in mice. Finally, we studied the effect of selegiline (a known cytochrome P450 mechanism-based inhibitor) on nicotine metabolism in mice and in human CYP2A6. RESULTS: Nicotine metabolism in mice in vitro was mediated by CYP2A5, and this enzyme was responsible for over 70% and 90% of the metabolism of nicotine to cotinine and cotinine to 3-hydroxycotinine as shown by immuno-inhibition studies, respectively. A polymorphism in CYP2A5 between mouse strains, known to alter the probe substrate coumarin’s metabolism, did not affect nicotine metabolism but dramatically altered cotinine metabolism. Nicotine self-administration behaviour in mice was associated with level of hepatic CYP2A5 proteins and rates of nicotine metabolism in male mice. In inhibition studies, the CYP2A5/6 inhibitor methoxsalen inhibited both in vitro and in vivo nicotine metabolism in mice and substantially increased the anti-nociceptive effect of nicotine. Finally, selegiline was found to be an inhibitor of CYP2A5 decreasing nicotine metabolism in vitro and in vivo in mice. Moreover, we showed that selegiline is a mechanism-based inhibitor of CYP2A6 inhibiting nicotine metabolism irreversibly. CONCLUSION: The above data suggested that the mouse model may be suitable for examining the impact of inhibition (and genetic variation) on nicotine metabolism and nicotine-mediated behaviours and may potentially be used to screen for novel inhibitors of nicotine metabolism.

INTRODUCTION: Smoking is one of the single greatest causes of numerous preventable diseases. We were interested in developing an animal model of nicotine metabolism that can be used to examine the effects of potential CYP2A6 inhibitors on nicotine metabolism and nicotine-mediated behaviours. Pharmacogenetic studies have demonstrated that in humans, smoking behaviour is associated with rates of nicotine metabolism by the CYP2A6 enzyme. Mouse CYP2A5 shares structural and functional similarities to human CYP2A6 and has been implicated in nicotine self-administration behaviours in mice, therefore the mouse represents a potential animal model for studying nicotine metabolism. METHODS: We characterized nicotine and cotinine metabolism in two commonly used mouse strains (DBA/2 and C57Bl/6). We also examined the association between nicotine self-administration behaviours and nicotine metabolism, and the impact of direct manipulation (i.e. inhibition) of nicotine metabolism on nicotine pharmacodynamics (hot-plate and tail-flick tests) in mice. Finally, we studied the effect of selegiline (a known cytochrome P450 mechanism-based inhibitor) on nicotine metabolism in mice and in human CYP2A6. RESULTS: Nicotine metabolism in mice in vitro was mediated by CYP2A5, and this enzyme was responsible for over 70% and 90% of the metabolism of nicotine to cotinine and cotinine to 3-hydroxycotinine as shown by immuno-inhibition studies, respectively. A polymorphism in CYP2A5 between mouse strains, known to alter the probe substrate coumarin’s metabolism, did not affect nicotine metabolism but dramatically altered cotinine metabolism. Nicotine self-administration behaviour in mice was associated with level of hepatic CYP2A5 proteins and rates of nicotine metabolism in male mice. In inhibition studies, the CYP2A5/6 inhibitor methoxsalen inhibited both in vitro and in vivo nicotine metabolism in mice and substantially increased the anti-nociceptive effect of nicotine. Finally, selegiline was found to be an inhibitor of CYP2A5 decreasing nicotine metabolism in vitro and in vivo in mice. Moreover, we showed that selegiline is a mechanism-based inhibitor of CYP2A6 inhibiting nicotine metabolism irreversibly. CONCLUSION: The above data suggested that the mouse model may be suitable for examining the impact of inhibition (and genetic variation) on nicotine metabolism and nicotine-mediated behaviours and may potentially be used to screen for novel inhibitors of nicotine metabolism.

Das Schweißen von WPC stellt zunächst aufgrund der thermoplastischen Matrix eine effektive Fügetechnologie dar. Der Beitrag behandelt das Heizelementschweißen von WPC und liefert Aussagen zur Wirkung der Prozessparameter auf die mechanischen und geometrischen Nahteigenschaften, dem Rezeptureinfluss und der thermischen Instabilität der Holzfaser. An den WPC-Rezepturen auf Basis von Polypropylen mit 40 Gew.-% und 50 Gew.-% Holzfasern sowie des Einsatzes von PET-Fasern im Compound, werden die Zusammenhänge untersucht und die Versagensmechanismen aufgezeigt.

Das Schweißen von WPC stellt zunächst aufgrund der thermoplastischen Matrix eine effektive Fügetechnologie dar. Der Beitrag behandelt das Heizelementschweißen von WPC und liefert Aussagen zur Wirkung der Prozessparameter auf die mechanischen und geometrischen Nahteigenschaften, dem Rezeptureinfluss und der thermischen Instabilität der Holzfaser. An den WPC-Rezepturen auf Basis von Polypropylen mit 40 Gew.-% und 50 Gew.-% Holzfasern sowie des Einsatzes von PET-Fasern im Compound, werden die Zusammenhänge untersucht und die Versagensmechanismen aufgezeigt.

Le caractère fortement hydrophile des isolants thermiques bio-sourcés, a montré que les modèles classiques de transfert thermique ne sont pas suffisamment adaptés pour leur caractérisation thermique. Ce travail de thèse vise à répondre à cette problématique par des approches expérimentale et théorique des transferts couplés chaleur-humidité. Dans l’approche expérimentale, un isolant thermique en feutre de fibres de lin (FFL) a été développé puis caractérisé, dans différents états hygrométriques, au moyen d’un dispositif Plan Chaud asymétrique. Des isothermes d’adsorption de l’humidité corrélés aux modèles théoriques GAB, GDW et Park permettent une caractérisation hydrique de cet isolant. Dans l’approche théorique, un modèle physique, de transfert couplé chaleur-humidité au sein de l’isolant FFL humide, est proposé. Il est résolu numériquement, en configuration 3D transitoire, par la méthode de éléments finis sous COMSOL Multiphysics et par la méthode des différences finies, en configuration 1D transitoire, sous MATLAB. La méthode de Levenberg-Marquardt couplée avec le modèle direct 1D transitoire et les températures mesurées a permis d’estimer la conductivité thermique apparente de l'échantillon étudié avec une erreur relative inférieure à 6% par rapport aux mesures expérimentales, validant ainsi les modèles théoriques. / The conventional heat transfer models are not sufficiently suitable for thermal characterization of bio-sourced thermal insulating materials due to their strongly hydrophilic nature. The proposed work in this PhD thesis aims to answer this problem with experimental and theoretical approaches of coupled heat-moisture transfers. In the experimental approach, a thermal insulating material based on Flax Fiber Felt (FFF) is developed and then characterized at different hygrometric conditions with an asymmetric hot plate device. The humidity diffusion characterization of the samples is done using the GAB, GDW and Park theoretical moisture adsorption isotherm models. In the theoretical approach, a physical model of heat and mass transfer is proposed. It is solved numerically, in transient 3D configuration, by the finite element method under COMSOL Multiphysics and, in transient 1D configuration, by the finite difference method under MATLAB. The Levenberg-Marquardt method coupled with the 1D transient direct model and the measured temperatures made it possible to estimate the apparent thermal conductivity of the studied sample with a relative error of less than 6% compared to the experimental measurements, thus validating the theoretical models.

This diploma thesis deals with the technology of noncontact hot plate welding and hot gas welding and with the optimizing of welding parameters of the chosen thermoplastics, especially of POM and PPA. The individual chapters in the theoretical part focus on following topics: technology of noncontact hot plate welding, technology of noncontact hot gas welding, description of the test welding machines and tools, main process parameters and evaluation of the advantages and disadvantages of each technology. In the practical part the welding parameters are optimized by the Design of Experiment systematic, the short-term capability machine and the microtome analysis are evaluated. In the end there are the results of the welding parameters optimization and comparison of noncontact welding technologies.

Made available in DSpace on 2015-05-14T13:00:16Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 1182383 bytes, checksum: 1ff4fac23517aa4b22351ae87d21b4be (MD5) Previous issue date: 2010-07-08 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The a, b-epoxy-carvone (EC) monoterpene is found in many essential oils from plants, but can also be obtained through organic synthesis from the R-(-)-carvone. Previous studies have demonstrated that this compound exerts depressant effect on central nervous system (CNS), and is also known to have anticonvulsant effects, antioxidant and antimicrobial activities. This study investigated the antinociceptive and antiinflammatory effects of EC in adult male Swiss mice, as well as, its effect on glutamatergic neurotransmission in rats using behavioral tests, vascular permeability test, measurement of paw edema and electrophysiological recordings in vitro, respectively. Intraperiotoneal administration (ip) of EC at doses of 200 or 300 mg/kg provided a significant antinociceptive effect as shown in the writhing test induced by acetic acid. The EC also caused a reduction in formalin-induced nociception in the first (at 300 mg/ g) and second phase (at 200 or 300 mg/kg). In the hot plate test an increase in latency was found at 30 min (at 200 or 300 mg/kg) and 60 min (300 mg/kg) after administration of EC, the effect that was reversed by naloxone, an opioid receptor antagonist. After administration of EC (300 mg / kg), the increased vascular permeability induced by acetic acid was reduced, as well as the paw edema induced by carrageenan. The EC reduced by 70% the excitatory postsynaptic potentials (EPSP) field, as well as the glutamatergic EPSP of the pyramidal neurons from the CA1 hippocampal region and the neurons from the nucleus of the solitary tract (NTS). These results suggest that EC has peripheral and central antinociceptive activity in mice, probably related to opioid system activation and inhibition of acute inflammatory reaction. In addition, EC has depressant effects on excitatory postsynaptic neurotransmission. / A a,b-epoxy-carvona (EC) é um monoterpeno encontrado em muitos óleos essenciais (OE s) de plantas, mas também pode ser obtida por meio da síntese orgânica a partir da R-(-)-carvona. Estudos prévios demonstraram que esse composto exerce efeito depressor no sistema nervoso central (SNC), e é também conhecida por ter efeitos anticonvulsivantes, antioxidante e antimicrobial. O presente estudo investigou os efeitos antinociceptivo e anti-inflamatório da EC, em camundongos suíços machos adultos, bem como seu efeito sobre a neurotransmissão glutamatérgica em ratos usando testes comportamentais, teste da permeabilidade vascular, medida de edema de pata e registros eletrofisiológicos in vitro, respectivamente. A administração intraperiotoneal (i.p.) da EC nas doses de 200 ou 300 mg/kg promoveu um efeito antinociceptivo significante como mostrado no teste das contorções abdominais induzidas pelo ácido acético. A EC também provocou redução na nocicepção induzida pela formalina na primeira (300 mg/kg) e na segunda fase (200 e 300 mg/kg). No teste da placa quente foi encontrado um aumento da latência aos 30 min (nas doses de 200 ou 300 mg/kg) e aos 60 min (na dose de 300 mg/kg) após a administração da EC, um efeito que foi revertido pela naloxona, um antagonista do receptor opióide. Após a administração da EC (300 mg/kg), o aumento da permeabilidade vascular provocado pelo ácido acético foi reduzido, bem como, o edema de pata em camundongos provocada pela carragenina. A EC reduziu em 70% os potenciais pós-sinápticos excitatórios (PEPS) de campo como também os PEPS glutamatérgicos dos neurônios piramidais da região CA1 do hipocampo e dos neurônios do núcleo do trato solitário (NTS). Estes resultados sugerem que EC apresenta atividade antinociceptiva periférica e central em camundongos, provavelmente associada à ativação do sistema opioidérgico, e inibição da reação inflamatória aguda. Além disso, EC exerce efeito depressor na neurotransmissão pós-sináptica excitatória.