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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.
251

Monitoramento e avaliação da emissão de dutos e fontes estacionarias de industrias ceramicas por meio de metodo potenciometrico e fluorescencia de raios X / Monitoring and evaluation of ducts and stationary source emissions from ceramic industries by potntiometry and X-ray fluorescence methods

Fonseca, Roney Jose da 31 August 2007 (has links)
Orientador: Silvana Moreira / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-11T08:53:13Z (GMT). No. of bitstreams: 1 Fonseca_RoneyJoseda_M.pdf: 1481408 bytes, checksum: 7f9822fbb599c31623b7b04f50171593 (MD5) Previous issue date: 2007 / Resumo: O objetivo deste trabalho foi monitorar e avaliar a emissão de fluoreto e de metais de dutos e fontes estacionárias de indústrias cerâmicas da região do Pólo Cerâmico de Santa Gertrudes (SP). Nos últimos anos houve um crescimento das empresas neste setor, causando reflexos ambientais nesta região responsável por 60% da produção de pisos esmaltados. O principal causador destes danos é o flúor na forma de fluoreto gasoso e ácido fluorídrico, comumente encontrado no solo e na argila utilizada na fabricação de pisos e artefatos cerâmicos. No período de 2004 a 2007 foram coletadas amostras dos gases emitidos por diversas indústrias cerâmicas desta região. Os compostos a base de flúor foram analisados por potenciometria e alguns metais pela técnica de fluorescência de raios X por reflexão total com radiação síncrotron. Altas concentrações de elementos como Cromo, Níquel e Chumbo foram observadas nas amostras analisadas e, em valores superiores aos permitidos pela legislação. No que se refere à emissão de fluoreto total foi verificado que 61,5% das empresas monitoradas apresentaram valores de emissão acima do permitido (5,0 mg/Nm3). Foi verificado ainda que o fluoreto foi emitido principalmente na forma de fluoreto gasoso. Desta forma a problemática ambiental na região de Santa Gertrudes não está associada apenas à emissão de flúor, mas também está relacionada à presença de metais pesados presentes em altas concentrações nas emissões atmosféricas provenientes do setor cerâmico / Abstract: The purpose of this work was monitoring and evaluation the emissions of fluoride and metals of ducts and stationary sources from ceramics industries of Santa Gertrudes region (SP). In recent years there had been a growth of companies in this sector, causing environmental repercussions in this region responsible for 60% of the production of porcelain tiles. The main cause of these damages is fluorine as fluoride gaseous and fluoridric acid, commonly found in soil and clay used in the manufacture of ceramic artifacts. During 2004 until 2007 gaseous samples were collected in different industries. The fluorine compounds were analyzed by potentiometry method and some metals by X-ray fluorescence analysis. High concentrations of Chromium, Nickel and Lead were observed in the samples and the values were higher than the permitted by the Brazilian legislation. In relation to fluoride emission 61,5% of the industries monitored showed values above the established by the legislation (5.0 mg/Nm3). In this way the environmental pollution in Santa Gertrudes region was not associated just to fluorine emission but also with the heavy metals present in high concentrations in the atmospheric emissions from stationary sources of ceramic industries / Mestrado / Saneamento e Ambiente / Mestre em Engenharia Civil
252

Construção de vetores de expressão para Escherichia coli baseados em promotores ativos na fase estacionária de crescimento

Wöhlke, Jonathan Luiz 21 September 2012 (has links)
Made available in DSpace on 2015-04-20T12:31:30Z (GMT). No. of bitstreams: 1 jonathan.pdf: 3096267 bytes, checksum: 8d8efe41b3d0eaa2b1ee28e28f9ebb5e (MD5) Previous issue date: 2012-09-21 / Plasmids are extrachromosomal genetic elements that generally are not essential for survival of the bacteria , however , provide unique advantages ( as resistance to antibiotics) for the organism. For genetic engineering, naturally occurring plasmids have been modified extensively for the production of vectors with the desired characteristics. Promoters are elements of a vector which may have a profound effect on the strength and duration of transcription and, consequently, the protein yield . The mRNA synthesis starts when RNA polymerase binds the promoter sequence adjacent to the target gene. Sigma factors are proteins that regulate transcription in bacteria , and they can be activated in different environmental conditions . The sigma factor ( S ) is seen as a master regulator of the general stress response , encoded from the gene RpoS in late stationary phase . This factor is the primary regulator of the genes stationary phase . Prosecutors based metabolic regulators of stationary phase represent a class of promoters metabolically controlled and can be exploited for the design of expression vectors . This project were developed three expression cassettes for construction of expression vectors , which have promoters with affinity for sigma factor S , in order to evaluate the expression profile of recombinant proteins in Escherichia coli . To evaluate the strength of promoters and expression profiling , we used the green fluorescent protein ( GFP ) as a reporter gene . The three vectors constructed, which were named p26 , p53 and PFS expressed GFP in the correct formation of the fluorophore , and the vector p26 and p53 showed overexpression of the recombinant protein when compared to the vector pGS21a . Furthermore , it was observed that the vectors constructed here are contributing to the reduction in the rate of growth and filamentation of E. coli. This gives the morphological plasticity bacterium higher storage capacity of the recombinant protein expressed . / Plasmídeos são elementos genéticos extracromossomais, que no geral não são essenciais para a sobrevivência da bactéria, entretanto, conferem vantagens peculiares (como resistência à antibióticos) para o organismo. Para engenharia genética, plasmídeos de ocorrência natural têm sido modificados extensivamente para produção de vetores com as características desejadas. Promotores são elementos de um vetor que podem ter um profundo efeito na força e duração da transcrição, e consequentemente, no rendimento proteico. A síntese de mRNA inicia quando a RNA polimerase se liga a sequência promotora , adjacente ao gene alvo. Fatores sigma são proteínas que regulam a transcrição em bactérias, e os mesmos podem ser ativados em diferentes condições ambientais. O fator sigma (S) é visto como um regulador mestre de resposta ao estresse geral, codificado a partir do gene RpoS na fase estacionária tardia. Este fator é o regulador primário dos genes de fase estacionária. Promotores baseados em reguladores metabólicos de fase estacionária representam uma classe de promotores controlados metabolicamente e que podem ser explorados para o design de vetores de expressão. Neste projeto foram desenvolvidos três cassetes de expressão para a construção de vetores de expressão, os quais possuem promotores com afinidade pelo fator sigma S, com o objetivo de avaliar o perfil de expressão de proteínas recombinantes em Escherichia coli. Para a avaliação da força dos promotores e do perfil de expressão, utilizou-se a proteína verde fluorescente (GFP) como gene repórter. Os três vetores construídos, os quais foram denominados de p26, p53 e pFS expressaram a GFP com a correta formação do fluoróforo, sendo que os vetores p26 e p53 apresentaram superexpressão da proteína recombinante, quando comparados ao vetor pGS21a. Ademais, observou-se que os vetores aqui construídos estão contribuindo para a redução da taxa de crescimento e filamentação da E. coli. Esta plasticidade morfológica confere à bactéria maior capacidade de armazenamento da proteína recombinante expressa.
253

Geração de ação dinâmica de estruturas baseada em transformada de wavelet harmônica. / Generation of dynamic loading of structure based in harmonic wavelet transform.

Paulo Salvador Britto Nigro 23 April 2009 (has links)
Neste trabalho, é apresentado um modelo aperfeiçoado para gerar carregamentos dinâmicos pseudo-aleatórios para modelos estruturais sob excitação sísmica e de vento. Este é baseado no modelo de vento sintético proposto por Franco, diferindo pelo fato que usa a transformada de wavelet harmônica ao invés da série de Fourier, pois tem como objetivo descrever um comportamento não estacionário com a ajuda de uma função temporal. Para testar a qualidade do sinal desenvolvido neste trabalho, este foi comparado com sinais verdadeiro, das acelerações de sismos ocorrido na cidade de Hachinohe, no Japão e em El-centro, na Califórnia, e com um sinal gerado pelo modelo do sismo sintético de Corbani, este também baseado no modelo de vento sintético, com o uso de séries de Fourier. Em todas as análises feitas, foi mostrando que embora a geração de carregamentos com transformadas de wavelet harmônica seja mais complexa, esta possui um bom potencial para gerar carregamentos mais próximos da realidade do que métodos usuais baseados em carregamentos estacionários. / In this work is intruduced a improve model to create random loads to use in structural models under sismic and wind disturbance. The model is based on synthetic wind model intends by Franco, differing by the fact that applies harmonic wavelet transform instead of Fourier series, because it has the goal to describe a non stationary behavior with temporal function support. To test the quality from the signal developed in this work, it has been analyzed against true seismic acceleration signal that occurs from Hachinohe city in Japan and El-centro city in California, and with the synthetic seismic model developed by Corbani, that one descending on synthetic wind model, with Fourier series application. In all analysis, although loading creation with harmonic wavelet transform have been more sophisticated, that one has a great potencial to creat loading closer to the fact than usual methods based in stationary loading.
254

Desenvolvimento e caracterização de fases estacionárias monolíticas baseadas em metacrilatos para uso em cromatografia líquida capilar / Development and characterization of monolithic stationary phases based on methacrylates for use in capillary liquid chromatography

Sato, Mariana Roberto Gama, 1984- 26 August 2018 (has links)
Orientador: Carla Beatriz Grespan Bottoli / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Química / Made available in DSpace on 2018-08-26T03:14:53Z (GMT). No. of bitstreams: 1 Sato_MarianaRobertoGama_D.pdf: 4595333 bytes, checksum: 8882cf8d1d6576b19fd550c9d1d84f8b (MD5) Previous issue date: 2014 / Resumo: O desenvolvimento da cromatografia líquida capilar (CLC), como uma alternativa à cromatografia líquida de alta eficiência, tem se destacado no âmbito da miniaturização, uma tendência geral em instrumentação analítica para separações cromatográficas. O objetivo deste trabalho foi desenvolver e caracterizar fases estacionárias monolíticas para uso em CLC, empregando monolitos poliméricos orgânicos baseados em metacrilatos hidrofóbicos e hidrofílicos. O preparo das fases estacionárias monolíticas foi realizado in situ, ou seja, o recheio foi moldado no interior das colunas capilares de 150 µm de diâmetro interno. Foram empregados os monômeros butil metacrilato, lauril metacrilato e trimetilolpropano trimetacrilato no preparo de fases estacionárias monolíticas para separações no modo fase reversa; o polietileno glicol dimetacrilato foi empregado no preparo de fases estacionárias para separações no modo HILIC. As condições de preparo das fases estacionárias monolíticas foram comparadas e envolveram a aplicação de diferentes métodos de iniciação da reação de polimerização, como iniciação por radiação UV e iniciação térmica. O simples entrecruzamento de um monômero multifuncional e a polimerização controlada via radical livre também foram aplicados como métodos de preparo dos materiais monolíticos. As fases estacionárias monolíticas foram caracterizadas por técnicas físicas, como microscopia eletrônica de varredura e porosimetria por sorção de nitrogênio; as colunas preparadas foram avaliadas cromatograficamente pela técnica de CLC. As fases estacionárias monolíticas mostraram eficiência cromatográfica de até 47000 pratos m-1 para a separação de alquilbenzenos no modo fase reversa e de até 45000 pratos m-1 para a separação de acrilamidas no modo HILIC / Abstract: The development of capillary liquid chromatography (CLC), as alternative to high performance liquid chromatography, has emerged in miniaturization studies, a common trend in analytical instrumentation for chromatographic separations. The goal of this work was to develop and characterize monolithic stationary phases for use in CLC, using organic polymer monoliths based on hydrophobic and hydrophilic methacrylates. Stationary phases were prepared in situ by molding of the material inside the capillary columns of 150 µm of internal diameter. The monomers butyl methacrylate, lauryl methacrylate and trimethylolpropane trimethacrylate was employed to prepare monolithic stationary phases for separations by reversed phase; polyethylene glycol was used to prepare monolithic stationary phases for separations by HILIC mode. The preparation conditions were compared and involved the application of different initiation methods for polymerization reactions, such as initiation by UV radiation and initiation by heating. The single crosslinking of multifunctional monomer and controlled free-radical polymerization were also applied as preparation methods of monolithic materials. The monolithic stationary phases were characterized by physical techniques as scanning electronic microscopy and nitrogen sorption porometry; the columns prepared were chromatographic evaluated by CLC. Stationary phases showed chromatographic efficiency up to 47000 plates m-1 for the separation of alkylbenzenes in reversed phase mode and up to 45000 plates m-1 for the separation of acrylamides by HILIC mode / Doutorado / Quimica Analitica / Doutora em Ciências
255

Strategic Sustainable Development for the Stationary Power Sector : Is Carbon Capture and Storage a Strategic Investment for the Future?

Chacón, Lisa, Hornblow, Benjamin, Johnson, Daniel, Walker, Chris January 2006 (has links)
An examination of the stationary power sector is performed using The Natural Step framework and Sustainability Principles (SP), in order to aid decision makers in developing policy to balance energy needs while reducing carbon dioxide (CO2) emissions in order to address climate change. Carbon capture and storage (CCS) is evaluated for its sustainability aspects, and is found to be a potentially sustainable approach which can be a bridging technology to a more sustainable energy mix, as well as a remediation technology which can remove CO2 from the atmosphere when utilized in combination with biomass fuel. Initial actions for restructuring the stationary power sector should emphasise demand reduction and efficiency efforts, followed by switching to renewable energy sources. If the first two strategies can not provide sufficient CO2 reductions, then investments in CCS technology may be an appropriate choice. CCS with coal-fired power can be a means to decouple CO2 emissions from fossil fuel use, but other SP violations associated with coal use must also be fully addressed before this strategy can be considered a truly sustainable option.
256

Exposants de Lyapunov d’opérateurs de Schrödinger ergodiques / Lyapunov exponents of ergodic Schrödinger operators

Metzger, Florian 08 June 2017 (has links)
L'objectif de cette thèse est de traiter de deux aspects différents de la théorie de l'exposant de Lyapunov de cocycles de Schrödinger définis par une dynamique ergodique. Dans la première partie, on s'intéresse aux estimées de grandes déviations de type Bourgain & Goldstein pour des cocycles quasi-périodiques, puis pour ceux définis par le doublement de l'angle. Après avoir montré que seule une estimée par dessus sur une bande complexe est nécessaire pour avoir la minoration, on redémontre cette inégalité pour une dynamique quasi-périodique en utilisant des techniques de mouvement brownien en lien avec des fonctions sous-harmoniques. Ensuite on adapte la méthode au cas du doublement de l'angle pour lequel on prouve des estimées de grandes déviations sur les branches inverses de cette dynamique. Dans la deuxième partie sont étudiés des cocycles de Schrödinger dont la dynamique est une somme de dynamiques quasi-périodique et aléatoire. On démontre que, dans le régime perturbatif, les développements asymptotiques de l'exposant de Lyapunov attaché à ces cocycles sont similaires à ceux déjà démontrés dans le cas aléatoire par Figotin & Pastur ou Sadel & Schulz-Baldes. L'analyse se fait en fonction du caractère diophantien ou résonant de l'énergie par rapport à la fréquence diophantienne de la partie quasi-périodique du potentiel. / In this thesis we are interested in the Lyapunov exponent of ergodic Schrödinger cocycles. These cocycles occur in the analysis of solutions to the Schrödinger equation where the potential is defined with ergodic dynamics. We study two distinct aspects related to the the Lyapunov exponent for different kinds of dynamics. First we focus on a large deviation theorem for quasi-periodic cocycles and then for potentials defined by the doubling map. We prove that estimates of Bourgain & Goldstein type are granted if an upper estimate involved in the theorem is true on a strip of the complex plane. Then we establish a new technique to prove this upper bound in the quasi-periodic setting, based on subharmonic arguments suggested by Avila, Jitomirskaya & Sadel. We adapt afterwards the method to the doubling map and prove a large deviation theorem for the inverse branches of this dynamics. In the second part, we establish an asymptotic development similar to the results of Figotin & Pastur and Sadel & Schulz-Baldes for the Lyapunov exponent of Schrödinger cocycles at small coupling when the potential is a mixture of quasi-periodic and random. The analysis distinguishes the cases when the energy is either diophantine or resonant with respect to the frequency of the quasi-periodic part of the potential.
257

Zpracování a vyhodnocení dat získaných z prototypu jednotky pro energetické využití biomasy / Processing and evaluation of experimental data measured at prototype unit for energetic utilization of biomass

Blažková, Blanka January 2008 (has links)
Main task of this final thesis is to analyse experimental measured data of prototype unit with output of 1 MW for energic biomass utilization. Furthermore the aim is to get acquainted with energic biomass problems utilization in middle output kettles and with stationary source legislation. To transfer measured value due to legislative conditions this diploma work solves the conversion procedure which is necessary to evaluate emission limits for measured concentration CO, SO2, NOX and stiff contaminating matters. My final work put emphasis on graphics processing in general tables and graphs with trends describtions. Endeavour is achieve discussion bilateral connection.
258

Rizika stacionárních zdrojů spojená s oceňováním škod na životním prostředí / Risk of stationary sources associated with valuation of environmental damage

Procházková, Michaela January 2015 (has links)
The problems with the environmental damage valuation which are caused by the stationary sources belong to the important issues to be solved. Due to the heavy industrial activity in the Czech Republic it is important to pay attention to the possible risks which can emerge from these sources and can impact the environment and the health condition of people. The thesis deals with the analysis of the present state of this problem. The analysis of the risks which come from the specific situation is made on its basis. The goal of this thesis is to propose the general procedure of the valuation of the incurred damage on the environment and the minimization of the risks.
259

Rám pro stacionární hydraulické zařízení / Frame of stationary hydraulic device

Klezla, Vojtěch January 2016 (has links)
The subject of this thesis is design and strength analysis of stationary hydraulic device. Strength analysis is made by the finite element method. The thesis describes design of used frames, profiles and other components, which are parts of the frame. Frame modification is proposed, based on the results of the strength analysis. These modifications are checked with strength analysis. The thesis includes drawing of weldment. The project has been carried out in cooperation with Bosch Rexroth, spol. s. r. o.
260

Asymptotic Expansions for Second-Order Moments of Integral Functionals of Weakly Correlated Random Functions

Scheidt, Jrgen vom, Starkloff, Hans-Jrg, Wunderlich, Ralf 30 October 1998 (has links)
In the paper asymptotic expansions for second-order moments of integral functionals of a class of random functions are considered. The random functions are assumed to be $\epsilon$-correlated, i.e. the values are not correlated excluding a $\epsilon$-neighbourhood of each point. The asymptotic expansions are derived for $\epsilon \to 0$. With the help of a special weak assumption there are found easier expansions as in the case of general weakly correlated functions.

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