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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

Tepelný výpočet ohřevné trubkové pece / Thermal calculation of direct fired heater

Sénáši, Martin January 2016 (has links)
The main aim of the thesis is to evaluete properties of a simplified thermal calculation of the direct fired heater published in the journal Applied Energy at 2010 and its application to specific industrial cases. At first, general issues of process heaters are talk over. Second, calculation model in cited article is briefly introduced. After that, custom computational model at program Maple is created in accordance with published article. Subsequently, the model is applied to the existing process furnaces in the form of a check calculation. An integral part of the work is also a detailed discussion of the results obtained.
72

Technologické možnosti využití odpadních jílovců pro výrobu páleného žárovzdorného ostřiva v šachtových pecích / Technological Possibilities of Using Waste Claystone for Manufacturing Refractory Grog burned in blast furnaces

Konečný, Martin January 2017 (has links)
Aluminosilicate refractory grog are being manufactured by firing refractory clays, claystone and shale. Firing takes place mainly in rotary or blast furnaces. However, when adjusting the raw material before firing in blast furnaces, the formation of the fine clay particles takes place. It is not possible to fire the fine particles in blast furnaces the usual way, which leads to the generation of waste. There is a possibility, however, to form briquettes of these particles, which can be fired in blast furnaces. This solution also brings the possibility of adjusting the mixture by using correction raw materials or other types of clay. Using this method, it is possible to produce a special refractory grog with specific properties.
73

On the Use of Physical Basis Functions in a Sparse Expansion for Electromagnetic Scattering Signatures

Halman, Jennifer I. 06 June 2014 (has links)
No description available.
74

Enunciação e representação : na conjuntura das Diretas Já! / Enunciation and representation : the conjucture of Diretas Já!

Gimenes Moralis, Edileusa 12 August 2018 (has links)
Orientadores: Eduardo Guimarães, Jean-Claude Zancarini / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Estudos da Linguagem / Made available in DSpace on 2018-08-12T14:01:49Z (GMT). No. of bitstreams: 1 GimenesMoralis_Edileusa_D.pdf: 1735406 bytes, checksum: 39f26d9196ab74ad596076174789a5e7 (MD5) Previous issue date: 2008 / Resumo: O homem é visto, por alguns estudiosos, como signo da necessidade e não manifestação da inteligência. Dito de outro modo, o homem deixa de agir pela razão quando a necessidade oprime a sua inteligência. Logo, estaria na apresentação do dissenso como uma reunião conflituosa de dois mundos que encontramos o que lhe é valioso, o denominador comum: o argumento. Por meio do argumento, o homem político vê dois mundos num só, daqueles que falam e daqueles que não falam. Pelo paradoxo das ordens políticas do comando, o comando do igual se sobrepõe ao desigual. Nesta ordem, do domínio de uns sobre os outros, a mudança só ocorre se o homem deixar de ser um agente passivo para se tornar ativo. Têm-se, então, duas ordens heterogêneas que estabelecem relações diferentes, por se vincular a leis diferentes. Inserido na teoria da Semântica Enunciativa, este trabalho teve o objetivo de refletir sobre a prática política de um ator político, Dante de Oliveira, em um momento específico da história do Brasil, que ficou conhecido como Movimento das Diretas Já, ocorrido entre 1983 e meados de 1984. Seu interesse esteve nos desdobramentos e nas conseqüências que este acontecimento produziu sobre as práticas políticas deste político quanto de outros. Buscou-se analisar sua proposta de emenda constitucional (conhecida como emenda Dante de Oliveira ou emenda das diretas) e acompanhar seus desdobramentos. A hipótese fundou-se no dizer de que este acontecimento enunciativo aparece como produtor da ocasião e da oportunidade específica de um ator político específico: o então deputado federal Dante de Oliveira. Foi por um conjunto de discursos políticos, proferidos pelo próprio ator político Dante que se transitou para realizar as análises. Na trajetória de suas práticas discursivas, interessou, em particular, a Emenda Constitucional PEC/5/1983 ou Emenda Dante de Oliveira que objetivava o fim da ditadura no Brasil, por meio da exigência de eleição direta para Presidente da República. Assim, o corpus constitui-se de fragmentos dos discursos proferidos durante o Movimento das Diretas Já!, construídos dentro de um regime militar. As análises procuraram estudar a argumentação de textos do corpus, bem como o funcionamento da designação da expressão "eleições diretas", e mais especificamente "diretas". Como ator político, Dante de Oliveira teve uma boa chance e uma boa oportunidade, na medida em que sua proposta se articulava de modo particular às aspirações do povo, naquele momento, por meio de um projeto audacioso. Como afirma Zancarini e Fournel (2002), é preciso saber avaliar uma conjuntura e traçar objetivos que respondam aos interesses do político e do povo pela ''boa chance e oportunidade''. Foi esta participação política de Dante de Oliveira que refinou sua biografia e a inscreveu na história com seu próprio nome: Emenda Dante de Oliveira. / Abstract: Man is seen by some researchers as a sign of necessity, and not as manifestation of intelligence. In other words, man's action is not oriented by reason when his intelligence is oppressed by necessity. So, it is in the presentation of dissention because of the conflicting meeting of two worlds what is precious to him, a common denominator: the argument. Through the argument, the political man sees two worlds in one, i.e., the world of people who speaks and the world of people who does not speak. In the paradox of political order of command, the command of equal is superposed to the unequal. In this order of domination of one on the others, changes came if man changes his role from active agent to passive agent. Different relations are placed by two heterogeneous orders because they are linked to different laws. Supported by the Enunciative Semantics, this work aims to be an inquiry on the political practices of the political actor Dante de Oliveira in a specific moment of Brazilian history in 1983 and the beginning of 1984: the popular movement Diretas Já!. Our interest is concerned with the unfolding and the consequences this political movement produced in the political practices of this man of politics and others. It was analyzed his Constitution Mending (The Dante de Oliveira Mending or Diretas Já! Mending) and its unfolding. Our hypothesis is founded by the assumption of this enunciative event as generator of the occasion and the specific opportunity of a specific political actor: the then congressman Dante de Oliveira. The analysis is concerned with a sample of political discourses delivered by the proper political actor Dante. In the course of his political practices this work is concerned specially with the Constitution Mending PEC/5/1983 or the Dante de Oliveira Mending. This mending aimed the end of dictatorship in Brazil, and required direct elections for president of the country. Consequently, the corpus of research is composed by analyses of discursive fragments delivered in the course of the military government Diretas Já!. In presenting a daring project the political actor Dante de Oliveira had a good chance and opportunity in that moment while his proposal was articulated in a particular way with people desire. According to Zancarini & Fournel (2002), it is necessary to consider circumstances and establish objectives that answer to the interests of the politician and of people by "good chance of opportunity". It was this political participation of Dante de Oliveira that refined his biography and inscribed him in history with his proper name: The Dante de Oliveira Mending. / Doutorado / Linguistica / Doutor em Linguística
75

Evaluation par imagerie isotopique des effets bénéfiques de progéniteurs endothéliaux circulants dans un modèle rongeur d'ischémie cérébrale focale transitoire / Evaluation by isotopic imaging of beneficial effects of endothelial progenitor cells in a rodent model of focal cerebral ischemia

Garrigue, Philippe 13 June 2016 (has links)
Les accidents vasculaires cérébraux (AVC) représentent l’une des premières causes de morbi-mortalité dans les pays industrialisés et sont en constante augmentation. Pour l’heure, aucune autre thérapie que la thrombolyse intraveineuse n’est validée, or moins de 10% des patients y sont éligibles.Les premiers essais de thérapie régénérative par greffe de progéniteurs endothéliaux ont montré leur efficacité au niveau préclinique sur la récupération fonctionnelle, mais très peu de cellules parviennent jusqu’au site de la lésion pour y exercer leurs effets. De précédents travaux ont montré que l’érythropoïétine (EPO) augmentait la mobilisation et la prolifération de progéniteurs endothéliaux depuis la moelle osseuse, ainsi que leur adressage vers les sites ischémiés in vivo.Nous avons formulé l’hypothèse que l’EPO pouvait permettre aux progéniteurs endothéliaux vrais (ECFCs) d’atteindre le site ischémié en plus grand nombre pour y exercer un effet plus important, plus rapidement. Nous avons donc décidé d’évaluer trois stratégies d’optimisation : coadministration d’ECFCs et d’EPO, administration d’ECFCs prétraités à l’EPO, et enfin coadministration d’ECFCs et d’un dérivé de l’EPO dénué d’effet hématopoïétique. Pour nos derniers travaux, nous nous sommes aidés de l’imagerie isotopique µSPECT/CT pour quantifier l’adressage au niveau de la lésion des ECFCs avec ou sans optimisation pharmacologique à l’EPO, et évaluer longitudinalement leurs effets bénéfiques sur la rupture de la barrière hémato-encéphalique, l’apoptose cérébrale et le débit sanguin cérébral résiduel, en complément des techniques référentes et de l’évaluation clinique neurofonctionnelle. / Stroke represents a leading cause of morbidity and mortality in industrialized countries and prevalence steadily increases. For now, no other therapy that intravenous thrombolysis is validated, still, less than 10% of patients are eligible.The first preclinical regenerative therapy trials using endothelial progenitor cells engraftment gave evidence of their efficacy on functional recovery, although very few cells reached the site of injury to exert their effects are. Previous works showed that erythropoietin (EPO) increased mobilization and proliferation of endothelial progenitor cells from bone marrow, as well as their homing to the ischemic sites in vivo.We hypothesized that EPO could enable true endothelial progenitor cells (ECFCs) to reach the ischemic site in larger quantity, faster, to exercise a greater effect. We decided to evaluate three optimization strategies: coadministration of ECFCs and EPO, administration of EPO-pretreated ECFCs, and finally coadministration of ECFCs and an EPO derivative devoid of hematopoietic effect.In this work, we used μSPECT/CT imaging to quantify the ECFCs homing to the ischemic site with or without EPO optimization after cerebral ischemia, and longitudinally assessed their beneficial effects on blood-brain barrier disruption, cerebral apoptosis and residual cerebral blood flow, complementary to the referent techniques and neurofunctional clinical evaluation.
76

Caractérisation de l'hydrophobie des polymères extracellulaires (PEC) extrait de biofilms : une étude basée sur la technique de la résine DAX-8 / Hydrophobic features of extracellular polymeric substances (EPS) extracted from biofilms : an investigation based on DAX-8 resin technique

Cao, Feishu 28 June 2017 (has links)
Les propriétés hydrophobes des polymères extracellulaires (PEC) exercent l’influence profonde sur les propriétés de la surface cellulaire. Cependant, de nombreux facteurs tels que les méthodes d'extractions, le type de substrat influencent les caractéristiques des PEC et les informations concernant des caractéristiques hydrophobes sont rarement documentées. L'objectif principal de cette étude est de développer une méthode appropriée pour étudier l'hydrophobicité des PEC, puis d'étudier les caractéristiques hydrophobes des PEC.Le fractionnement hydrphobe par la résine Supelite™ DAX-8 a d'abord été appliqué sur les PEC extraits de boues granulaires anaérobies, deux conditions de pH d'élution (pH 2 et 5) ont été testées. L'impact de sept méthodes d'extraction sur les caractéristiques hydrophobes des PEC a été évalué. Les résultats ont montré que les méthodes d'extraction et le pH de la solution extraitante ont influencé la composition des PEC et leur hydrophobicité. En outre, les extraitants des PEC, par exempe le formaldéhyde, l'éthanol, le dodécylsulfate de sodium (SDS) et Tween 20, ont non seulement introduit une teneur supplémentaire en carbone pendant la mesure du carbone organique total (COT), mais ils ont également interagit avec la résine DAX-8. En comparant la répartition du poids moléculaire apparent (aMW) des échantillons des PEC non traités et ajustés au pH détectés par chromatographie d'exclusion stérique (en anglais SEC), l’information plus complète d’aMW a été préservée à pH 5. Ainsi, le fractionnement hydrophobe par la résine DAX-8 à pH 5 et les méthodes physiques d'extraction PEC ont été préférés dans cette étude.Une analyse qualitative détaillée des caractéristiques hydrophobes des EPS a été étudiée par la technique de la matrice de fluorescence d’excitation-emission (EEM). Les résultats ont montré que les substances de type humique (HS-like) représentaient la majorité des composés organiques des PEC extraits de la boue granulaire anaérobie, et constituaient également le principal support moléculaire de l'hydrophobicité des extraits. Ces composés hydrophobes de type HS étaient essenciellement des molécules petites tailles de 8 kDa à <1 kDa. L’hydrophobité contributée par les protéines (PN) et les polysaccharides (PS) présentait un moindre rapport.Afin d’explorer les propriétés hydrophobes de PN et de PS, ainsi évaluer l'impact de l'addition de Ni(II) sur l'hydrophobicité des extraits des champignons, fongi Phanerochaete chrysosporium a été choisi. Les résultats ont montré que la teneur de PN et de PS dans les PEC extrait de ce type de fongi variait en fonction de la concentration de Ni(II). Avec une augmentation de la concentration de Ni de 0 mg/L à 25 mg/L, la teneur en PN a diminué alors que celle de PS a été augmentée. L'hydrophobicité des PEC du fongi, déterminée par le traitement de la résine DAX-8, a diminué lors que la concentration de Ni augmentait. Par ailleurs, l'intensité du pic de SEC correspondant aux molécules PN-like (Ex/Em = 225/345 nm) de 1,9 × 103 à 10 kDa a été augmentée par l'addition Ni; en même temps, la distribution d’aMW des composés organiques totaux (UV/210) dans les PEC restait presque stable. Ces résultats ont indiqué que les composés de type PN-like peuvent avoir déterminé l'hydrophobicité des PEC fongique dans des conditions de stress.Dans l’extrait plus hétérogène des PEC de boues granulaires anaérobies, des composés HS-like représentaient le composant organique majeur, ainsi le principal support moléculaire de l'hydrophobicité des PEC. En étudiant les caractéristiques hydrophobes des PEC extrait du champignon Phanerochaete chrysosporium, le PN et le PS des PEC jouaient un rôle actif dans la protection du champignon sous le Ni. La concentration élevée de Ni a diminué l'hydrophobicité des PEC fongique, mais elle a augmenté l'hydrophobicité de la surface cellulaire du champignon. Il semble que la présence de Ni favorise l'apparition d'un champignon plus hydrophobe / The hydrophobic properties of extracellular polymeric substances (EPS) exert a profound influence on the cell surface properties. However, many factors such as EPS extractions methods, substrate type influence EPS characteristics, and limited information regarding to the hydrophobic features of EPS can be found. The main aim of this study is to develop a proper method to study EPS hydrophobicity, and then investigate the hydrophobic features of EPS.The hydrophobic fractionation by Supelite™ DAX-8 resin was first applied on the EPS extracted from anaerobic granular sludge, two elution pH conditions i.e. pH 2 and 5 were tested. The impact of seven EPS extraction methods on the hydrophobic features of EPS was assessed. The results showed that the extraction methods and bulk solution pH dramatically influenced the EPS composition and their hydrophobicity. Besides, the EPS extracting reagents namely formaldehyde, ethanol, sodium dodecyl sulfate (SDS) and Tween 20 not only introduced extra carbon content during total organic carbon (TOC) measurement, but also interacted with the DAX-8 resin. By comparing the apparent molecular weight (aMW) distribution of the untreated and pH-adjusted EPS samples detected by size exclusion chromatography, more complete EPS aMW information was preserved at pH 5. Thus, the hydrophobic fractionation by DAX-8 resin at pH 5 and physical EPS extraction methods were preferred in this study.After identifying the proper conditions for DAX-8 resin fractionation, detailed qualitative analysis of the EPS hydrophobic features was further investigated. The results showed that the humic-like substances (HS-like) were the major organic constituent of the EPS extracted from the anaerobic granular sludge, and they were also the main molecular support of the EPS hydrophobicity. Those hydrophobic HS-like compounds were mainly small molecules ranging from 8 kDa to <1 kDa. Proteins (PN) and polysaccharides (PS) contributed to the EPS hydrophobicity to a lesser extent.The role of PN and PS in the EPS hydrophobicity was difficult to be shown. It is known that the major organic constituents of the EPS extracted from bacteria, algae and fungi are PN and PS. Therefore, to explore the hydrophobic features of PN and PS, as well as to investigate the impact of Ni(II) addition, on the EPS hydrophobicity, the fungus Phanerochaete chrysosporium was chosen. The results showed that the contents of PN and PS in the extracted fungal EPS varied with the Ni(II) concentration. With an increase in the Ni concentration from 0 mg/L to 25 mg/L, the PN content was decreased whereas the PS content was increased. The fungal EPS hydrophobicity, determined by the DAX-8 resin treatment, was decreased as the Ni concentration increased.Besides, the peak intensity on the size exclusion chromatography (SEC) corresponding to the PN-like molecules (Ex/Em = 225/345 nm) ranging from 1.9×103 to 10 kDa were intensified by the Ni addition, while the aMW distribution of the total organics (UV/210) in the EPS remained almost stable. These results indicated that those PN-like compounds may determine the hydrophobicity of fungal EPS under stress conditions.For the more heterogeneous EPS extracted from anaerobic granular sludge, HS-like compounds were identified as the major organic component, as well as the main molecular support of the EPS hydrophobicity. By studying the hydrophobic features of the EPS extracted from the fungus Phanerochaete chrysosporium, it showed that the PN and PS in the EPS played an active role in protecting the fungus under Ni stress. The increased Ni concentration decreased the hydrophobicity of fungal EPS, but it increased the cell surface hydrophobicity of the fungus. It seems that the presence of Ni promoted the fungus becoming more hydrophobic
77

Štěrbinová anténa / Slot antenna

Dvořák, Petr January 2014 (has links)
This thesis discusses Slot antennas that are based in gap waveguide technology, which allows them to work with high frequency signals. It contains theoretical findings about antennas and waveguides, which are later used in the design. The practical section of this thesis concentrates on designing a specific gap waveguide for 10 and 24 GHz frequencies, starting with modeling and parameter optimalization. This gap waveguide is then used as a base for slot antenna design. The final antenna is designed for frequency of 10 GHz, for both linear and right-handed circular polarizations. With right-handed circular polarization, the achieved band was approximately 1.41 GHz, while the gain was 7,6 dB.
78

Tuhnutí odlitků ve skořepinových formách při odlévání ve vakuu / Solidification of castings by pouring into shell moulds in vakuum furnaces

Odložil, Jan January 2009 (has links)
Heat transfer during metal pouring and its solidification in the vacuum furnace have been investigated by experiments using model set of castings of different diameters and insulations. The pouring metal was Inconel 713LC alloy based on nickel. The found data have been used for optimization of the numerical simulation of the thermal regime during the both pouring and solidification phases of the process in vacuum. Numerical simulation of the alloy structure in individual castings has been made by the CAFE module of the ProCast software and obtained results compared with the real structure. The optimized boundary conditions can be used for simulation of real castings.
79

Energetické využití komunálního odpadu / Recovery of Energy from Municipal Wastes

Šíma, Kamil January 2010 (has links)
The topic of the diplome thesis is draft of the waste-to-energy plant for municipal waste with cogeneration of heat. Basic specification of project: Waste-to-Energy plant is facilitated by two rotary kilns of type operating in parallel. Further flue gas leaving the post-combustor enters a multicyclone unit to separate substatial portion of fly-ash. Heat of flue gas at the temperature of 1000°C generates superheated steam in a Heat Recovery Steam Generator (HRSG). Dry sorption process is appllied for flue gas treatment. Specifically sodium bi-carbonate is used for it. Products of reactions and remnants of dust are separated by a baghouse. Superheated steam, generated by two HRSG, presents the inlet stream of a condensing steam turbine with steam extraction. The diploma thesis contains calculation of major devices and basic economical and financial statement of project.
80

Konstrukční návrh pece / Furnace design

Stříž, Michal January 2012 (has links)
This master´s thesis deals with issues of tube furnaces in the process industries, especially with a design of a transfer pipeline, which is one of the main parts of the furnace. According to the requirements, designed pipeline is stress analyzed using the two pipeline programs Japar and Caesar II, that are briefly described. In addition to this design several variants of analysis are performed and the results are compared. Comparison helps to explain the diversity of the programs. For example, the effect of elbows on the stress analysis. The master´s thesis also describes the factors that affect the working life of the furnace.

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