In this thesis, the treatments of MEA and the special structures within carbon fiber bunch unipolar plates on the performance of PEMFC are studied. At first, the factors affecting on the water content within MEA will be studied. A passive HFC stack usually exposes in the ambient no matter that it works or not. However, the ambient is far from saturated. The water within MEA will vaporize continuously. Especially, if the stack is shutdown for a long period, there is no water generation in the cathode and then the membrane will be short in water. If it occurs, the conductivity of H+ will decrease greatly, and the electrode of MEA is also possible to separate from its membrane. This separation will make the performance of the stack an unrecovered decay. On the other hand, in order to improve the performance of a air-breathing HFC, the inner structure within cathode carbon fiber bunch unipolar plates is modified. The structure of the unipolar plates is modified in the following three aspects: 1. Increasing soft end height of carbon fiber bunch, 2. Increasing the number of silver-coated wires in carbon fiber bunch, 3. Cutting several serrated slots on the soft end of carbon fiber bunch. In the MEA treatment, firstly, a MEA is boiled in 80oC, 0.5M H2SO4 solution and then boiled in 80oC DI water for an hour, respectively. When the single-cell HFC operates in hydrogen inlet pressure 0.1 bar, air-breathing, and room temperature, experimental results display that the power density of this HFC with the aforementioned treatments and the special structure of unipolar plates can reach a value about 185mW/cm2. This value is about 130% higher than that of the untreated MEA and about 50% higher than that of the treatment of MEA only immersed in DI water. In addition, the comparison of the performance of HFC between with carbon fiber bunch unipolar plates and with graphite unipolar plates are also studied. The experimental result displays that the performance of HFC with the carbon fiber bunch unipolar plates is superior to that with graphite unipolar plates, especially the fuel cell operating under low gas inlet pressure.

Untreated depression has a detrimental effect in the lives of the adolescents suffering from this disorder. Depression is a multidimensional phenomenon that has been linked to biological, psychosocial and cognitive risk factors. Adolescents may be at risk for depression because adolescence is a time of physical, hormonal, emotional and intellectual changes. Depression may lead to impaired social and school performances and to poor physical health. In addition to a reduced quality of life, depression has also been linked to suicidal ideation and attempts. Suicide is the third cause of death in adolescents in the United States.The purpose of this practice inquiry was to conduct a critical review and synthesis of the literature on evidence-based treatment of unipolar depression in adolescents and to make recommendations for health care providers. This topic was chosen because of the high prevalence of depression in adolescents and because of the devastating effects of not treating this disorder.The methods used to synthesize the literature are described in the Guide for Literature Reviews by Cooper (1998). After the problem was identified, a literature search was conducted in PubMed, Cinahl, Psych Info, Complementary and Alternative Medicine and AMED. Next, the literature yielded 93 articles. The evidence from the literature was ranked according to the Oncology Nursing Society (ONS), Putting Evidence into Practice (PEP), Levels of Evidence scale. This system is an adaptation of the Rating the Quality of Evidence for Clinical Practice Guidelines developed by Hadorn and others (1996). Lastly, the recommendations for practice were made based on the ONS PEP, Weight of Evidence Classification Schema by Mitchell & Friese. Based on the evidence found in the literature, a guideline with the recommendations for practice was developed.The need for the treatment of adolescents with depression was supported in this synthesis of the literature. Future research is needed to explore treatment modalities tailored to the developmental, biological, psychosocial and cultural needs of adolescents and their families.

This thesis examines the impact of the New World Order on the Arab-Israeli peace process. It argues that, since the collapse of the Soviet Union and the end of the Cold War, the old bipolar World Order has disappeared and a new unipolar one has emerged. The United States of America, as the only remaining single superpower, has enjoyed a great degree of influence and a kind of hegemony in international affairs. Its military superiority and economic, technological and diplomatic strength, in the absence of any competing power, have given it the upper hand to pursue its own policies and its own interests. This American unipolarity and hegemony are clearly demonstrated in the Middle East peace process. The United States' unipolarity on the international level and its hegemony on the regional level have allowed it to pursue policies to resolve the Arab- Israeli conflict. Regional states, released from the constraints or protection of the patron- client relationships fostered under the bi-polar Old World Order, have adjusted their own policies to take into account this New World Order. A neo-realist understanding of this has been developed which assesses this process in terms of international and regional balance of power and "rules of the game”. This method had been used to understand the reasons for and nature of the Arab- Israeli peace negotiations that started at Madrid in 1991 and developed in Oslo in 1993. The thesis argues that these negotiations were in fact a single process which was the direct result of this American-led New World Order. Whether through direct or indirect American involvement or through the indirect or direct acknowledgement by regional actors of the nature of the New World Order, American interests and preferences have been strongly reflected in the peace process.

M.Tech. (Homoeopathy) / Please refer to full text to view abstract

L’objectif de ce travail est de vérifier l’hypothèse selon laquelle les troubles olfactifs peuvent êtres des marqueurs de la dépression et différencier entre dépression unipolaire et dépression bipolaire. Dans ce projet, nous avons évalué et comparé les capacités olfactives de plusieurs groupes de sujets : patients en dépression unipolaire ou bipolaire, symptomatique ou en rémission, ainsi que des témoins sains. Nos résultats confirment la présence de marqueurs olfactifs d’état (seuil et mémoire olfactive, identification des odeurs), et de trait (jugement hédonique et émotionnel) de la dépression unipolaire et des marqueurs d’état (mémoire olfactive) et de trait (jugement hédonique et émotionnel, identification des odeurs et mémoire olfactive) de la dépression bipolaire. Nous avons aussi trouvé des marqueurs de différenciation des dépressions unipolaire et bipolaire (jugement hédonique). Il s’agit de la première étude différenciant la dépression unipolaire de la dépression bipolaire à travers les marqueurs sensoriels. D’autres études sont nécessaires afin de montrer l’utilité de l’olfaction dans la prise en charge des troubles de l’humeur. / The objective of this research was to test the hypothesis that olfactory dysfunctions can constitute potential markers of depression, and that they help differentiating between unipolar and bipolar depression. In this project, we evaluated and compared the olfactory capacities of healthy controls and patients with unipolar and bipolar depression, in symtpomatic phases and in rémission. Our results confirmed the presence of state (olfactory threshold, olfaction memory and identification) and trait (hedonic and emotional ratings) markers of unipolar depresison and state (olfactory memory) and trait (hedonic and emotional rating, olfactory memory and identification) markers of bipolar depression. We identified an olfactory marker differentating between unipolar and bipolar depression (hedonic rating). This is the first study differentating unipolar depression from bipolar one through a sensory marker. Further studies are needed to show the utility of olfaction in the treatment of mood disorders.

In this thesis, we propose a three-dimensional (3D) fold-up non-classical unipolar complementary metal-oxide semiconductor field-effect transistor (CMOS-FET) structure and its operation mechanism. We utilize a NMOS transistor having punch-through effect and a classical NMOS to realize our proposed CMOS circuit. In our proposed CMOS circuit, both driver and load transistors are based on the n-channel MOS (NMOS) structures, so, in this unipolar CMOS, the carrier used is the electron only. Hence, the delay time can be improved by 14% when compared with the conventional CMOS. Moreover, the p-channel MOS (PMOS) transistor can be eliminated in our proposed CMOS circuit. Thus, we do not need the traditional N-well technique and we also use the 3D device architecture to drastically reduce the total device area more than 69%, in comparison to a conventional CMOS. If our proposed CMOS architecture is implemented in the VLSI circuits, the packing density can be increased and the device fabrication cost can also be reduced significantly. Therefore, our proposed 3D fold-up non-classical single-carrier CMOS-FET can achieve three important requirements as follows: 1) area reduction, 2) enhanced speed, and 3) decrease cost in the system fabrication.

In this paper, we propose a novel Unipolar CMOS device in which the transport carriers are electron only. And we achieve good inverter output waveform and logic circuit applications by simulation. Duo to all n-channel (NMOS) structures are used, we call this proposed CMOS as a Unipolar CMOS. A new basic theory of utilizing the punch through effect is demonstrated to enhance the tPLH in our proposed Unipolar CMOS. The average delay time compared with the classical CMOS circuit can be improved 23% for high-performance applications. For our proposed Unipolar CMOS, all n-channel MOS are used to eliminate the N- and P-well processes and ignore the difference between the carrier mobility. In addition, the common electrodes are also exploited, hence, the layout area can be reduced to about 75%, which leads to significantly increase the packing density of CMOS circuits in the same chip.

The problem of the performance decay and the factors affecting on the DMFC performance for long-term operation are studied in this thesis. First, the influence of the initial treatments of MEA and the exposure of MEA in the atmosphere on the water content are measured. In addition, the effects of the pressure of the MEA hot press conditions, the treatments and preservation of MEA, and the operative conditions on the performance are also examined. Eventually, we expect that the best way to increase the DMFC performance and avoid the performance can be found. These can provide for references when a portable DMFC need to be designed and manufactured in future. In order to solve the problem of methanol crossover leading to the cathode poisoned, cells are operated only under the proper methanol concentration and discharged thoroughly before finishing the whole experiment. It is also necessary to maintain MEAs in proper wetness so that the performance of stack will not decay too quickly. In the initial treatment, firstly, a MEA is immersed in 3M MeOH and then boiled with 80oC DI water for an hour, respectively. The experimental conditions of this passive single-cell DMFC are pumpless in anode chamber, air-breathing, and room temperature. The power density of this DMFC with these test conditions can reach a value about 33mW/cm2. This value is about 106% higher than that of the untreated MEA. If MEA boiled with 0.5M H2SO4 for an hour and then boiled with 80oC DI water for an hour, its power density is about 75% higher than that of the untreated MEA.

Abstract Traditional unipolar/bipolar plates, such as the metal and the graphite unipolar/bipolar plates, are expensive, weight heavy and volume large, so that it is hard to be used in the portable application. A high efficiency, low cost and lightweight portable proton exchange membrane fuel cell (called PEMFC or called HFC when using pure hydrogen fuel), which is made with a new heterogeneous composite carbon fiber bipolar plate and a MEA, is developed in our lab. There are many advantages of the new carbon fiber unipolar/bipolar plates, such as low contact resistance, low cost, lightweight and small volume. We hope that the new unipolar/bipolar plate will be able to replace the conventional metal and graphite unipolar/bipolar plates in the future. The characteristics of a portable PEMFC in different operational conditions are studied in this research. From our experimental result, we find that the factors which affect the HFC performance include the gas temperature, humidity ratio, inlet gas pressure in anode, the geometry of inlet ports, the flow channels within cell, and the oxidant flow rate etc. In addition, the contact resistances between different materials within each cell all strongly influence HFC performance. The ribs of the carbon fiber unipolar/bipolar plates is pored structure, and the gas diffusion layer is no deformation because of only slight compression in stack assembly; therefore, the reactive gas can easily flow into the most of active area. In addition, the contact resistance between the carbon fiber unipolar plate and the gas diffusion layer is lower than that between the traditional unipolar plate and the gas diffusion layer, so that the electrons in active layer is easily to exit or enter this region. The experimental result at 1.15 atm and 40 oC displays that the current density with the new unipolar plate is about twice higher than that with the graphite unipolar plate at overpotential 0.6 V. With air as an oxidizer, we find that increasing the fan rotation speed can avoid output-voltage decay in high current density, but the design with fan is unfavorable for portable application. So a front open unipolar plate and air-breathing design is adopted on the cathode. The power density of this design is slightly lower than that with fan, but it still can reach a value 160 mW/cm2 without any heating and humidification in the anode. Because this design needs little supplement device, the application in portable fuel cells of the new design will be wider than that of a traditional design.

The experimental test and analysis of the direct methanol fuel cell (DMFC), which is made with a newly developed heterogeneous composite carbon fiber unipolar/bipolar plate, is performed in our lab. The work from the making of carbon fiber unipolar plate to the design of single-cell DMFC is also included in this study. The experimental work of various control parameters, such as methanol concentration, operating temperature, and the air flow rate, is also conducted in this thesis. The formation of carbon dioxide in anode is inspected during experiment. From a series of experimental test, we have understood the characteristics of DMFC better. The experimental result and experience can also provide the references of the application and development of DMFC in the future. According to our experiment, we find that the assembling of the new-type unipolar/bipolar plate doesn¡¦t need to use the large compressing force to reduce the contact resistance like those of the traditional unipolar/bipolar plates. The structure of the DMFC stack made with the new carbon fiber unipolar/bipolar plate is simple and weight light. However, the experimental results still show that the factors that affect the performance of the DMFC fuel cell are similar to those with the conventional unipolar/bipolar plates. For example, increasing the reactive temperature of fuel, proper methanol concentration, and proper content of catalyst all can effectively improve the power density of a DMFC. The structure of the methanol mixture directly stored in the flow channel of the anode is simple. However, the design exists the problems of the crossover of methanol, the stripping of the anode electrode, and the removal of the carbon dioxide. Special attention is needed to overcome and improve those problems in making DMFC stacks. Or the performance of the cell will decline after long period operation.