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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.
221

Efeitos da incorpora??o de areia reciclada de res?duos de constru??o e demoli??o (RCD) em argamassas mistas de revestimento / Effects of the incorporation of recycled sand of construction and demolition waste (CDW) in mixed coating mortars

Ferreira, Ruan Landolfo da Silva 31 March 2017 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-06-02T22:25:25Z No. of bitstreams: 1 RuanLandolfoDaSilvaFerreira_DISSERT.pdf: 5373766 bytes, checksum: 13b9b589b54063a3ed114c1d60d827c5 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-06-08T22:20:54Z (GMT) No. of bitstreams: 1 RuanLandolfoDaSilvaFerreira_DISSERT.pdf: 5373766 bytes, checksum: 13b9b589b54063a3ed114c1d60d827c5 (MD5) / Made available in DSpace on 2017-06-08T22:20:54Z (GMT). No. of bitstreams: 1 RuanLandolfoDaSilvaFerreira_DISSERT.pdf: 5373766 bytes, checksum: 13b9b589b54063a3ed114c1d60d827c5 (MD5) Previous issue date: 2017-03-31 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / O processo de constru??o, reforma e demoli??o, pode ocasionar significativos problemas ao meio ambiente, devido a extra??o de mat?rias primas e a destina??o inadequada dos res?duos gerados. Em especial os res?duos de constru??o e demoli??o (RCD) que, comumente correspondem a mais da metade dos res?duos s?lidos urbanos, tem como principais destinos, terrenos baldios, margens de estradas e rios, acarretando s?rios impactos ambientais, sociais e econ?micos. Atualmente, a reutiliza??o de agregados reciclados (AR), especialmente de composi??o mista, ? estudada em menor grau, quando comparado aos AR de concreto. Com isso, por n?o possuir alternativas para sua utiliza??o, uma grande quantidade desse tipo de AR ? armazenada pelas usinas. Nesse sentido, buscou-se analisar a viabilidade t?cnica e econ?mica da utiliza??o de AR com diferentes composi??es granulom?tricas e em condi??o lavada, ? n?veis de substitui??o de 25, 50, 75 e 100% do agregado natural (AN), na produ??o de argamassas mistas de revestimento. Para a produ??o das argamassas, utilizou-se cimento CP II Z-32, cal CH-I e uma propor??o em volume de 1:1:6, cujo teor de ?gua foi determinado para as misturas alcan?arem uma consist?ncia de 260 mm. Inicialmente, analisou-se as propriedades f?sicas, qu?micas, mineral?gicas e microestruturais dos agregados e da fra??o de finos (<0,15 mm). Buscando avaliar a viabilidade t?cnica das argamassas foram caracterizadas no estado fresco, por meio dos ensaios de consist?ncia, reten??o de ?gua, densidade de massa e teor de ar incorporado. E no estado endurecido, a resist?ncia ? compress?o, resist?ncia ? tra??o na flex?o, m?dulo de elasticidade din?mico, absor??o por capilaridade, absor??o por imers?o, resist?ncia de ader?ncia e fissura??o. Foi utilizado o custo para produzir 1 m? de argamassa visando avaliar a viabilidade econ?mica. Constatou-se, que as argamassas com AR, independentemente de sua composi??o granulom?trica ou condi??o, apresentaram maior consumo de ?gua, menor densidade de massa e teor de ar incorporado, assim como adequada capacidade de reten??o de ?gua. No estado endurecido, as argamassas que possu?am AR com a presen?a de finos, apresentaram maior resist?ncia, maior m?dulo de elasticidade e menor porosidade e permeabilidade. No entanto, o desempenho dos revestimentos frente ao potencial de ader?ncia ao substrato e a quantidade de fissuras, foi inferior, confirmando a premissa de que a utiliza??o de AR com finos n?o ? indicada para a produ??o de argamassas de revestimento. Quanto a viabilidade econ?mica, ao incorporar o AR, o custo para produzir 1 m? de argamassa diminui. No entanto, admite-se que ? vi?vel a utiliza??o de AR para a produ??o de argamassas de revestimento, especialmente quando se disp?e de agregados com adequada composi??o granulom?trica, isentos de finos e em condi??o lavada. / The construction, reform and demolition process can cause significant problems to the environment due to the extraction of raw materials and an inadequate disposal of the waste generated. In particular, construction and demolition wastes (CDW), which commonly correspond to more than half of urban solid waste, have as main destinations, vacant lots, roadsides and rivers, causing serious environmental, social and economic impacts. Currently, a recycling of recycled aggregates (RA), especially of mixed composition has been studied to lesser extent when compared to RA of concrete. Therefore, because it does not have alternatives for their use, a large amount of this type of RA is stored by plants. In this sense, the aim of this research is to analyze the technical and economic viability of the use of RA with different grain size and washed condition compositions, at 25, 50, 75 and 100% substitution levels of the natural aggregate (NA), in the production of mixed mortars. For the production of mortars, CP II Z-32 cement, lime CH-I and a volume ratio of 1:1: 6 were used. Water content was adjusted to mixtures with a consistency of 260 mm. Initially, the physical, chemical, mineralogy and microstructural properties of the aggregates and the fines fraction (<0.15 mm) were analyzed. Seeking to assess the technical feasibility of mortars were characterized fresh, through consistency tests, water retention, bulk density and entrained air content. And in the hardened state, the compressive strength, flexural tensile strength, dynamic modulus of elasticity, water absorption by capillarity, immersion absorption, adherence strength and susceptibility to cracking. The cost of production of 1 m? of mortar was used for an assessment of economic feasibility. It was showed that, as mortars with RA, regardless of their size distribution or condition, presented higher water consumption, lower bulk density and incorporated air content, as well as water retention capacity. In the hardened state the mortars had RA with the presence of thin, had higher resistance, higher modulus and lower porosity and permeability. However, the performance of the mortar coverings to the potential of adhesion to the substrate and a number of cracks has been lower, confirming a premise that the use of RA with fines is not indicated for coating mortars. As for the economic feasibility, to incorporate RA, the cost to produce 1 m? of mortar decreases. However, it is recognized that the use of RA for the production of coating mortars is feasible, especially when aggregates with adequate size distribution are available, without fines and in washed condition.
222

Obten??o e estudo de um comp?sito de matriz de poli?ster e carga de res?duos de m?rmore

Costa, Larissa Caroline Fernandes 07 April 2017 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-08-01T12:12:38Z No. of bitstreams: 1 LarissaCarolineFernandesCosta_DISSERT.pdf: 2007912 bytes, checksum: 69954dca07d2068ae02c52bd9db08760 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-08-03T20:10:46Z (GMT) No. of bitstreams: 1 LarissaCarolineFernandesCosta_DISSERT.pdf: 2007912 bytes, checksum: 69954dca07d2068ae02c52bd9db08760 (MD5) / Made available in DSpace on 2017-08-03T20:10:46Z (GMT). No. of bitstreams: 1 LarissaCarolineFernandesCosta_DISSERT.pdf: 2007912 bytes, checksum: 69954dca07d2068ae02c52bd9db08760 (MD5) Previous issue date: 2017-04-07 / Apresenta-se um comp?sito formado por resina poli?ster e carga de res?duos de p? de m?rmore (RPM) produzidos pelo corte de pedras ornamentais. O res?duo produzido foi processado para a obten??o de p?s. V?rias formula??es do comp?sito foram testadas, variando-se o percentual de carga em rela??o ?s reninas de poli?ster, cristal ou escura. Todas as formula??es escolhidas, 50% RPM, 100% RPM, 150% RPM, 200% RPM e 250% RPM apresentaram viabilidade de processamento e obten??o do comp?sito. O p? de m?rmore e os comp?sitos produzidos foram caracterizados para a determina??o de propriedades f?sicas, mec?nicas e t?rmicas. Os resultados da caracteriza??o das formula??es do comp?sito mostraram que o p? de m?rmore esteve presente no comp?sito como carga de enchimento. A propriedade em que o comp?sito apresentou melhor resultado que a resina matriz foi ? resist?ncia ao impacto. Analisando-se a processabilidade, todas as formula??es do comp?sito apresentaram-se vi?veis, para as duas resinas estudadas. O comp?sito demonstrou-se vi?vel para a fabrica??o de mesas, cadeiras, pranchas, obras de arte, pe?as para banheiros, divis?rias para ambientes, estruturas que n?o requerem resist?ncia ? grandes esfor?os. Uma importante vantagem do comp?sito estudado ? a diminui??o da quantidade de resina a ser utilizada, uma vez que a carga de p? de res?duo pode alcan?ar 250% em rela??o ? matriz, diminuindo-se o custo do material obtido para a fabrica??o de estruturas diversas. O comp?sito polim?rico mostrou-se vi?vel para substituir pedras de m?rmore e granito naturais. / It presents a composite formed by polyester resin and load of marble dust residues (RPM) produced by the cut of ornamental stones. The residue produced was processed to obtain powders. Several composite formulations were tested by varying the load percentage relative to polyester, crystal or dark renin. All formulations chosen, 50% RPM, 100% RPM, 150% RPM, 200% RPM and 250% RPM presented feasibility of processing and obtaining the composite. The marble powder and composites produced were characterized for the determination of physical, mechanical and thermal properties. The results of the characterization of the composite formulations showed that the marble powder was present in the composite as a filler. The property in which the composite presented better results than the matrix resin was the impact strength. Analyzing the processability all the formulations of the composite were feasible, for the two resins studied. The composite has proven to be feasible for the manufacture of tables, chairs, planks, works of art, parts for bathrooms, partitions for environments, structures that do not require resistance to great efforts. An important advantage of the composite studied is the decrease in the amount of resin to be used, since the residue powder load can reach 250% in relation to the matrix, reducing the cost of the material obtained for the manufacture of various structures. The polymer composite proved to be feasible to replace natural marble and granite stones.
223

Problemas socioambientais: urbaniza??o desordenada e consequ?ncias para a qualidade das ?guas subterr?neas de Po?os localizados nas imedia??es do lix?o de Cidade Nova em Natal/RN

Bezerril, Kellia de Oliveira 04 February 2016 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-10-04T19:34:40Z No. of bitstreams: 1 KelliaDeOliveiraBezerril_DISSERT.pdf: 5932090 bytes, checksum: 423ec312fe919813070b66476287b4af (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-10-10T22:26:17Z (GMT) No. of bitstreams: 1 KelliaDeOliveiraBezerril_DISSERT.pdf: 5932090 bytes, checksum: 423ec312fe919813070b66476287b4af (MD5) / Made available in DSpace on 2017-10-10T22:26:17Z (GMT). No. of bitstreams: 1 KelliaDeOliveiraBezerril_DISSERT.pdf: 5932090 bytes, checksum: 423ec312fe919813070b66476287b4af (MD5) Previous issue date: 2016-02-04 / O crescimento desordenado da capital potiguar ocorrido a partir da d?cada de 1970 ocasionou s?rios problemas ambientais urbanos. Nesse contexto de r?pido incremento populacional, a constitui??o do Lix?o de Cidade Nova ampliou a problem?tica socioambiental por via da emiss?o elevada de chorume no solo culminando na contamina??o do len?ol fre?tico, o que trouxe s?rios problemas para a qualidade do abastecimento h?drico da popula??o. Desta forma, a presente pesquisa busca analisar a rela??o entre a contamina??o gerada pela deposi??o dos res?duos s?lidos no Lix?o de Cidade Nova por mais de tr?s d?cadas e o prec?rio esgotamento sanit?rio implantado nos bairros de Felipe Camar?o, Planalto e Guarapes. Foi feito levantamento bibliogr?fico para a discuss?o sobre esta rela??o entre urbaniza??o, problem?tica socioambiental e contamina??o de ?guas subterr?neas. Al?m disso, foi feito tamb?m um levantamento sobre a estrutura f?sica da ?rea de estudo, assim como das legisla??es relativas ? tem?tica. Ainda no plano metodol?gico, foi feita pesquisa de campo nos po?os destinados ao abastecimento h?drico P1 e P5 no bairro de Felipe Camar?o e P2 no bairro do Planalto no per?odo de maio de 2014 a maio de 2015. Os resultados da pesquisa demonstram que h? contamina??o das ?guas destinadas ao abastecimento humano nos referidos bairros, e que esta adv?m da inadequada deposi??o de res?duos s?lidos no solo, assim como da aus?ncia de um adequado esgotamento sanit?rio. A pesquisa apresenta como conclus?o a constata??o de latente necessidade de pol?ticas p?blicas que atenuem tais problemas no contexto socioambiental da ?rea estudada. / The uncontrolled growth of Natal occurred at the 1970s caused serious urban environmental problems. In this context, the establishment of the ?Cidade Nova? trash dump has expanded social and environmental problems by the high emission of contaminant itens on the soil, resulting in contamination of the water table, which brought serious problems for the quality of the water supply. This research aims to relate the pollution caused by the deposition of solid waste in ?Cidade Nova? trash dump for more than three decades and the precarious sanitation deployed in the districts of Felipe Camar?o, Planalto and Guarapes, with the consequent contamination of the wells of respective districts for human consumption. For this purpose, the literature was researched to the discussion about the relationship between urbanization, environmental issues and contamination of groundwater. Furthermore, was made a research about the physical structure of the study area, even as about the laws on the subject. About the methodology, a massive fieldwork was done in the wells for the water supply P1 and P5 at the Felipe Camar?o district, and P2 at Planalto, from May/2014 to May/2015. The survey results show that there are contamination of the water intended for human consumption in those districts, and that this stems from the improper disposal of solid waste in the soil, beyond the absence of adequate sanitation, concluding that there are a latent need for public policies that mitigate such problems in the socio-environmental context of this area of study.
224

The implicit Res Judicata and the Right of Defense / La Cosa Juzgada Implícita y el Derecho de Defensa

Apolín Meza, Dante Ludwig 12 April 2018 (has links)
This article presents the analysis of the concept of the “implicit res judicata” and what problems it generates. To do this, the author analyzes what is traditionally understood by “objective limits” of “res judicata” and, from this; the true scope of the concept of “res judicata” implicitly will be established. / Este artículo plantea el análisis del concepto de cosa juzgada implícita y los problemas que genera. Para ello, se analiza lo que tradicionalmente se ha entendido por límites objetivos de la cosa juzgada y, a partir de ello, se establecerá el verdadero alcance del concepto de cosa juzgada implícita.
225

Julgamento fracionado do mérito e suas implicações no sistema recursal / Partial judgment on the meritis: implications for appeal system

Silas Dias de Oliveira Filho 03 June 2013 (has links)
O Poder Judiciário brasileiro encontra-se em crise, sendo a excessiva morosidade dos processos seu principal ponto sensível. Diante disso, foram introduzidas alterações normativas destinadas a amenizar o grave cenário existente, como a Emenda Constitucional n. 45/04, que incluiu a razoável duração do processo no rol dos direitos e garantias fundamentais, e a Lei n. 11.232/05, que alterou a estrutura do processo civil de conhecimento e o conceito de sentença. A indigitada reforma processual implicou rompimento com o princípio da unicidade da sentença, possibilitando o fracionamento do julgamento de mérito, por meio de sentenças parciais. O presente estudo verificará as possibilidades e os limites de aplicação dessa técnica processual, bem como proporá solução a problemas surgidos no sistema recursal, o qual não foi adaptado à nova realidade processual existente. A cisão no julgamento do mérito também traz importantes reflexos no momento de formação da coisa julgada material, tema que foi recentemente objeto de análise pelo Superior Tribunal de Justiça. Analisar-se-á o acerto do posicionamento adotado pela jurisprudência, buscando-se alcançar conclusão que tenha o condão de extrair o máximo de efetividade do método estatal de resolução de conflitos. O tema é intrigante, apresentando diversas possibilidades. Não há dúvidas de que do fracionamento do exame do mérito decorrerão dificuldades e dúvidas, as quais devem ser solvidas pelos operadores do direito, em prol de um processo mais efetivo e capaz de produzir os resultados que dele se esperam / The Brazilian Judiciary is in crisis and the excessive length of proceeding isits main sore point. Therefore, legislative amendments were introduced,aiming at alleviating the serious existing scenario, as the Constitutional Amendment 45/04, which included the reasonable duration of the process (speedy trial clause) in the list of fundamental rights and guarantees, and Law 11.232/05, which changed the structure of civil procedure and the concept of sentence. The nominee procedural reform entailed breaking with the principle of unity of the sentence, allowing the fractionation of judgment, through partial sentences. This study will examine the possibilities and limits of application of this technique, and propose solution to problems arising in the appeal system, which was not adapted to the new reality. The split in judging the merit also carries important consequences on the formation of res judicata, a topic that has recently been examined by the Superior Tribunal de Justiça. The correctness of the position adopted by the jurisprudence will be analyzed, seeking to reach a conclusion that has the power to extract the maximum effectiveness of the state method of conflict resolution. The topic is intriguing, presenting several possibilities. There is no doubt that from the partial judgment of merits derives difficulties and doubts, which should be answered by law operators, in favor of a more effective process and capable of producing results that are expected of it.
226

O erro na ação rescisória / The error in actions for reversal of judgment

Fabiana Monteiro Parro 10 May 2011 (has links)
O presente trabalho tratou do erro na ação rescisória, compreendendo tanto o erro de fato como o erro de direito, apontando eventuais equívocos e acertos da doutrina e jurisprudência sobre o tema. Na primeira parte do estudo estabeleceu-se as premissas necessárias para as demais, iniciando-se por uma breve introdução a respeito da prestação jurisdicional e seus escopos, pois a ação rescisória não só é meio de prestação jurisdicional, como também é meio de revisão dessa mesma tutela prestada pelo Estado, passando-se, posteriormente, a uma sucinta apresentação da garantia da coisa julgada. Em seguida, ingressando já no tema da ação rescisória, na parte segunda traçou-se um panorama geral acerca do instituto, estabelecendo as principais diferenças entre a ação rescisória e os demais meios de impugnação das decisões judiciais, nos quais se insere a ação rescisória, dando ênfase à excepcionalidade do instituto ora em estudo, justamente por ser meio de revisão da coisa julgada, que goza de proteção constitucional. Na terceira parte, analisou-se o objeto da ação rescisória, que são as sentenças de mérito transitadas em julgado, apontando as possíveis decisões que podem abrir oportunidade ao manejo da ação rescisória, inclusive tratando de questão atual, que concerne à nova definição de sentença de mérito, concluindo-se pela impossibilidade de cisão formal da sentença, bem como examinou-se as principais divergências existentes no que tange às demais decisões, terminando, ainda, com uma breve abordagem do tratamento conferido à ação rescisória no anteprojeto do Código de Processo Civil. Finalmente, na quarta parte, foram feitas considerações sobre as principais questões que surgem em relação ao erro na ação rescisória à luz da doutrina nacional e italiana, bem como acerca dos erros e acertos da jurisprudência dos tribunais superiores a respeito do tema. Demonstrou-se que, para a ação rescisória por erro de fato exige-se apenas a existência de um requisito, qual seja, a ausência de controvérsia sobre ponto a respeito de que a sentença teve que se pronunciar ou teria que se pronunciar. Quanto ao erro de direito, concluiu-se que, para fins da ação rescisória, não é necessário nem que a norma seja clara, nem que a violação se dê contra a literalidade da norma, pois, dificilmente um órgão julgador irá contrariar uma norma de forma clara e frontal. / This paper addresses the error in actions for reversal of judgment, including both errors in fact and errors at law, and points out some possibly mistaken and correct understandings of legal scholars and case law on the subject. The first part of this study lays down the premises required for its other parts, beginning with a short introduction regarding jurisdictional relief and its scopes, since an action for reversal of judgment is not only a means of seeking jurisdictional relief, but also a means of revising such relief as provided by the State. Then, a brief presentation is given on the assurance of res judicata. Next, now entering the realm of actions for reversal of judgment, its second part provides an overview of their institution, setting forth the main differences between actions for reversal of judgment and other means of challenging court rulings, wherein actions for reversal of judgment are included, emphasizing the exceptional nature of the institution studied herein, precisely because such actions are a means of revising a res judicata, which enjoys constitutional protection. Its third part analyzes the subject-matter of actions for reversal of judgment, aimed at judgments on merit that have become res judicata, pointing out rulings that possibly can afford an opportunity for pursuing an action for reversal of judgment, including in dealing with a current issue, which concerns a new definition of judgment on merit, and then it concludes for the impossibility of formally splitting a judgment. It also examines the main existing divergences as regards other rulings, and it closes, furthermore, with a brief discussion of the treatment given to actions for reversal of judgment in the preliminary bill of law for the Code of Civil Procedure. Finally, in its fourth part, some comments are made on the main issues that arise in connection with errors in actions for reversal of judgment, in light of Brazilian and Italian legal scholarship, and on some mistaken and correct understandings in the case law of higher courts regarding the subject. It is demonstrated that for an action for reversal of judgment upon an error of fact, only one existing requirement is called for, namely, the absence of any dispute over a point that had to be heard, or would have to be heard, in the judgment. As for errors at law, the conclusion is reached that for the purposes of an action for reversal of judgment, it is neither necessary for the rule to be clear nor for the violation to be against the literalness of the rule, because a judging authority will hardly contradict a rule in a clear and outright manner.
227

Caracteriza??o de placas de circuito impresso oriundas de telefones celulares e recupera??o de cobre / Circuit boards printed characterization coming from mobile phones and copper recovery

Jesus, Theo Antonio de 23 January 2015 (has links)
Submitted by Celso Magalhaes (celsomagalhaes@ufrrj.br) on 2017-06-01T14:05:35Z No. of bitstreams: 1 2015 - Theo Antonio de Jesus.pdf: 3265233 bytes, checksum: 84b1c9854e0877f1a010f74527aca2e5 (MD5) / Made available in DSpace on 2017-06-01T14:05:35Z (GMT). No. of bitstreams: 1 2015 - Theo Antonio de Jesus.pdf: 3265233 bytes, checksum: 84b1c9854e0877f1a010f74527aca2e5 (MD5) Previous issue date: 2015-01-23 / Technological advances encourages the constant exchange of electronic equipment by increasing the amount of waste generated. The concern with the disposal of these wastes is related to the amount of available metals and final disposal, which usually occurs in dumps or landfills. These wastes have precious metals and other trace elements that are released into the environment by leaching from the organic acid attack. Most of these residues has printed circuit boards in which are concentrated the most metals, and the characterization of these plates help to choose the most appropriate recycling processes. This study aimed to characterize the printed circuit boards of mobile phones as its danger and composition as well as preliminarily investigate the possibility of copper recovery via an electrolytic process and test a mixture of coagulant / flocculant in the removal of metals, including copper. The plates were ground knives in order to release the metals and then separating the particle size was made in three fractions of different sizes. Each of the fractions was characterized by digestion in aqua regia, diffraction and X-ray fluorescence characterization, as the danger was performed through recommended by the ABNT NBR 10005. In the fractions resulting from the grain size were performed gravity separations. For the recovery of copper was used in electrolytic technique medium prepared with the electrolyte coming from the gravimetric fraction with a higher concentration of metals. The copper recovery efficiency through electrolytic process was evaluated by the decrease of its concentration in the electrolyte at five different times. Also, the use of coagulant mixture / flocculant had their efficiency assessed by check which proportion coagulant / flocculant used resulted in solution with lower concentrations of metals. It is also made of copper recovery compared by both methods. Mechanical processes are used to promote adequate concentration of most metals with approximately 80% in the coarser fraction using the separation grain size. The characterization results showed that the printed circuit boards of mobile phones are rich in copper, mean values reaching 40%, in addition to having small amounts of gold and silver. In the study of danger, lead levels were found in amounts well above the limit established by ABNT NBR 10004, requiring specific treatments at the disposal of this type of waste. Some proportions coagulant / flocculant used produced better results than others, getting, on average, above 90% removal. The recovery of copper showed better performance using the electrolytic process, compared to that obtained at any ratio coagulant / flocculant used once reached 98.05 % after 40 minutes. It was estimated the average revenue generated in the recovery of metals from the main printed circuit boards of mobile phones discarded in 2013 in Brazil, reaching the amount of US $ 6,182,263.06 / O avan?o tecnol?gico incentiva a troca constante dos equipamentos eletroeletr?nicos aumentando a quantidade de res?duos gerados. A preocupa??o com a disposi??o desses res?duos est? relacionada com a quantidade de metais existentes e sua disposi??o final, que geralmente se d? em lix?es ou aterros. Estes res?duos apresentam metais preciosos e outros elementos tra?os que s?o liberados no meio ambiente pela lixivia??o proveniente do ataque de ?cidos org?nicos. A maior parte destes res?duos possui placas de circuito impresso onde est? concentrada a maior parte dos metais, sendo que a caracteriza??o destas placas ajuda na escolha dos processos de reciclagem mais adequados. Este trabalho teve como objetivo caracterizar as placas de circuito impresso de telefones celulares quanto sua periculosidade e composi??o, bem como investigar preliminarmente a possibilidade de recupera??o de cobre via um processo eletrol?tico e testar uma mistura de coagulante/floculante na remo??o de metais, inclusive cobre. As placas foram processadas em moinho de facas, a fim de liberar os metais e, em seguida, foi feita a separa??o granulom?trica em tr?s fra??es de diferentes tamanhos. Cada uma das fra??es foi caracterizada por digest?o em ?gua r?gia, difra??o e fluoresc?ncia de raios X. A caracteriza??o, quanto ? periculosidade, foi realizada por meio do preconizado pela NBR ABNT 10005. Nas fra??es oriundas da granulometria foram realizadas as separa??es gravim?tricas. Para a recupera??o de cobre foi utilizada a t?cnica eletrol?tica por meio de eletr?lito preparado com a fra??o oriunda da gravimetria com maior concentra??o de metais. A efici?ncia da recupera??o de cobre via processo eletrol?tico foi avaliada por meio da diminui??o de sua concentra??o no eletr?lito em cinco tempos diferentes. J? a utiliza??o da mistura coagulante/floculante teve sua efici?ncia avaliada pela verifica??o de qual propor??o coagulante/floculante utilizada resultou em solu??o com menor concentra??o de metais. Fez-se tamb?m a compara??o de recupera??o de cobre por ambos os m?todos. Os processos mec?nicos utilizados foram adequados para promoverem a concentra??o da maioria dos metais alcan?ando cerca de 80 % na fra??o mais grosseira utilizando-se a separa??o granulom?trica. Os resultados da caracteriza??o mostraram que as placas de circuito impresso de celulares s?o ricas em cobre, alcan?ando valores m?dios de 40 %, al?m de apresentarem pequenas quantidades de ouro e prata. No estudo de periculosidade, foram encontrados n?veis de chumbo em quantidades muito acima do limite estabelecido pela NBR ABNT 10004, sendo necess?rios tratamentos espec?ficos no descarte deste tipo de res?duo. Algumas propor??es de coagulante/floculante utilizadas produziram resultados mais satisfat?rios que outras, ficando, na m?dia, acima dos 90 % de remo??o. A recupera??o de cobre apresentou melhor desempenho utilizando processo eletrol?tico, quando comparado ao obtido a qualquer propor??o de coagulante/floculante utilizada, uma vez que alcan?ou 98,05 % ap?s 40 minutos. Foi estimada a receita m?dia gerada, na recupera??o dos principais metais contidos nas placas de circuito impresso dos telefones celulares, descartados em 2013, no Brasil, chegando-se ao valor de US $ 6.182.263,06.
228

Uhelné elektrárny: levná elektřina vs. čisté životní prostředí / Coal-fired power plants: cheap electricity vs. clean environment

Krydl, Ondřej January 2015 (has links)
The aim of this thesis is to analyze the importance of coal-fired power plants on the market of electric energy, with emphasis on aspects that fundamentally affect their production. Coal-fired power plants belongs nowadays among socially unpopular source of electricity. In recent decades intensively growing interest groups that support state intervention and regulation of the energy sector. This is essentially a massive promotion of renewable energy sources at the expense of fossil fuel plants. Analysis of individual power sources shows that despite the current restrictive measures imposed on power plants burning fossil fuels, and especially coal-fired power plants, electricity produced from coal resources is still competitive, despite some drawbacks has many positive qualities. Coal-fired power plants produce higher amounts of greenhouse gases and other pollutants than other types of power plants. On the other hand, they are able to provide a stable supply of electricity to transmission network, and thus partially offset the high volatility of electricity supply from renewable energy sources. The price of electricity from coal-fired power plants could be considered as relatively low in comparison with other energy sources. The analysis shows that in terms of practical economic policy is not economically justified to reduce the proportion of coal-fired power plants in the total production of electricity.
229

Národohospodářský význam výroby elektrické energie z obnovitelných zdrojů v ČR / Economic importance of electricity from renewable energy sources in the Czech Republic

Procházka, Štěpán January 2012 (has links)
This thesis deals with the national economy importance of electricity from renewable energy sources in the Czech Republic. The theoretical part introduces the different types of RES legislation relative to RES and energy intensity of the economy of the Czech Republic. Analytical part shows the financial impact of support RES in the Czech Republic to year 2030.
230

Vývoj obchodu elektřinou v rámci EU / Development of trade in electricity in the EU

Fučík, Václav January 2013 (has links)
The main aim of this thesis is analysis of history, present and future development of cross-border trade in electricity in the EU. A number of instruments is used -- analysis of generation mix, the role of renewables, degree of international interconnection and usage of these routes, institutional organization of the sector and price convergence of national markets. The research's output is the description of past and recent development and a forecast of possible future progress at the national level. The outcome of this thesis enables the reader to fully understand the complexity of EU electricity market and its probable future direction.

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