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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.
11

An?lise das emiss?es gasosas de um ve?culo flex funcionando com diferentes combust?veis

Holanda, Raphael Araujo de 17 February 2011 (has links)
Made available in DSpace on 2014-12-17T14:08:44Z (GMT). No. of bitstreams: 1 RafhaelAH_DISSERT.pdf: 3286080 bytes, checksum: f7d63c2f5fde3101ddffb2cd1417b11d (MD5) Previous issue date: 2011-02-17 / Efforts in research and development of new technologies to reduce emission levels of pollutant gases in the atmosphere has intensified in the last decades. In this context, it can be highlighted the modern systems of electronic engine management, new automotive catalysts and the use of renewable fuels which contributes to reduce the environmental impact. The purpose of this study was a comparative analysis of gas emissions from a automotive vehicle, operating with different fuels: natural gas, AEHC or gasoline. To execute the experimental tests, a flex vehicle was installed on a chassis dynamometer equipped with a gas analyzer and other complementary accessories according to the standard guidelines of emission and security procedures. Tests were performed according to NBR 6601 and NBR 7024, which define the urban and road driving cycle, respectively. Besides the analysis of exhaust gases in the discharge tube, before and after the catalyst, using the suction probe of the gas analyzer to simulate the vehicle in urban and road traffic, were performed tests of fuel characterization. Final results were conclusive in indicating leaded gasoline as the fuel which most contributed with pollutant emissions in atmosphere and the usual gasoline being the fuel which less contributed with pollutant emissions in atmosphere / Nas ?ltimas d?cadas tem se intensificado os esfor?os em pesquisa e desenvolvimento de novas tecnologias para redu??o dos n?veis das emiss?es de gases poluentes na atmosfera. Neste contexto, destacam-se os modernos sistemas de gerenciamento eletr?nico do motor, os novos catalisadores automotivos e a utiliza??o de combust?veis renov?veis que contribuem para o menor impacto ambiental. A presente pesquisa teve como prop?sito a an?lise comparativa das emiss?es gasosas de um ve?culo automotivo, funcionando com diferentes combust?veis: g?s natural, AECH, ou gasolina. Para execu??o dos testes experimentais, um ve?culo flex foi instalado em um dinam?metro de chassi equipado com analisador de gases e demais acess?rios complementares ao atendimento das diretrizes das normas de emiss?o e procedimentos de seguran?a. Os ensaios foram realizados de acordo com as normas NBR 6601 e NBR 7024, que definem o ciclo de condu??o urbano e estrada, respectivamente. Al?m da an?lise dos gases de escapamento no tubo de descarga, antes e ap?s o catalisador, utilizando a sonda de aspira??o do analisador de gases, para simula??o do ve?culo em tr?fego urbano e estrada, foram realizados testes de caracteriza??o dos combust?veis. Os resultados finais foram conclusivos em apontar a gasolina aditivada como o combust?vel que mais contribuiu com as emiss?es de poluentes na atmosfera e a gasolina comum sendo o combust?vel que menos contribuiu com as emiss?es de poluentes na atmosfera
12

S?ntese e caracteriza??o de materiais mesoporosos inorg?nico-org?nicos para aplica??o na adsor??o de g?s carb?nico

Dantas, Taisa Cristine de Moura 26 July 2016 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-02-17T18:51:45Z No. of bitstreams: 1 TaisaCristineDeMouraDantas_TESE.pdf: 4130731 bytes, checksum: 1cb82be7c6c1b80529423696ce7dcfef (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-02-17T21:16:26Z (GMT) No. of bitstreams: 1 TaisaCristineDeMouraDantas_TESE.pdf: 4130731 bytes, checksum: 1cb82be7c6c1b80529423696ce7dcfef (MD5) / Made available in DSpace on 2017-02-17T21:16:26Z (GMT). No. of bitstreams: 1 TaisaCristineDeMouraDantas_TESE.pdf: 4130731 bytes, checksum: 1cb82be7c6c1b80529423696ce7dcfef (MD5) Previous issue date: 2016-07-26 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / A necessidade de encontrar novas tecnologias para a minimiza??o da emiss?o crescente de gases poluentes no planeta se torna cada vez mais urgente. Dos processos estudados atualmente a t?cnica de adsor??o utilizando materiais mesoporosos v?m tendo bastante enfoque. A fam?lia do SBA est? dentro desses materiais, onde pode ser destacado o SBA-15 e SBA-16 como estruturas com propriedades texturais interessantes. O presente trabalho realizou a s?ntese destes materiais de acordo com a metodologia descrita na literatura. Ap?s estas etapas, as estruturas de sil?cio foram funcionalizados atrav?s das t?cnicas de impregna??o com um pol?mero Polietilenimina ramificada com etilendiamina (PEI) em meio metan?lico, onde a rea??o das aminas com a estrutura de sil?cio apresenta car?ter i?nico; e a funcionaliza??o por enxerto com organossilanos, empregando o N-[(3-trimetoxissilil)propil] dietilenotriamina (DT-NNN), onde a estrutura ? formada de um grupo de sil?cio e tr?s aminas. A rea??o dessa mol?cula com a superf?cie de sil?cio ? realizada atrav?s de uma liga??o covalente. Tamb?m houve a funcionaliza??o do SBA-16 utilizando a dupla funcionaliza??o combinando as duas t?cnicas para obter uma maior porcentagem aminas. A parte foi proposta a reciclagem do material de sil?cio SBA-15, onde ap?s a funcionaliza??o, foram tratados termicamente a uma temperatura de 550 ?C para a elimina??o dos grupos org?nicos. A cada etapa de funcionaliza??o foi executada na estrutura uma nova etapa de funcionaliza??o, onde estas foram repetidas por 6 vezes. Os materiais foram caracterizados por t?cnicas f?sico-qu?micas no intuito de verificar a forma??o da estrutura e sua organiza??o. O processo de adsor??o de CO2 puro para o material SBA-16 funcionalizado foi executado em um equipamento volum?trico sob press?o de 1 bar a 45 ?C, onde a amostra E-SBA16-10PEI e CC-SBA16-50PEI exibiram quantidades de adsor??o de 47 mg CO2/g ads e 108 mg CO2/g ads, respectivamente. Os ensaios de adsor??o para o SBA-15 foram realizados tamb?m a 1 bar e 45 ?C, e menos quantidades de CO2 adsorvidos foram reportadas para as amostras com DT e isto pode ser relacionada a perda da efici?ncia das aminas. Esse comportamento n?o foi observado nas amostras impregnadas com PEI. / The need to find new technologies to minimize the increasing emission of greenhouse gases on the planet becomes increasingly urgent. Currently processes studied the adsorption technique using mesoporous materials are having enough focus. The family of the SBA is within these materials, which can be highlighted the SBA-15 and SBA-16 as structures with interesting textural properties. In the present work was carried out the synthesis of these materials according to the methodology described in the literature. After these steps, the silicon structures were functionalized by means of impregnation techniques with a branched polyethylenimine polymer etilendiamina (PEI) in the methanolic medium, where the reaction of amines with the silicon structure has ionic character; and graft functionalization with organosilanes, where we used the N [(3-trimetoxissilil) propyl] diethylenetriamine (DT- NNN) where the structure is formed from a group of silicon and three amines. The reaction of this molecule with the silicon surface is performed through a covalent bond. There was also the functionalization of SBA-16 using double functionalization combining the two techniques to get higher percentage amines. The part was proposed recycling of SBA-15 silicon material, which after functionalization, were heat-treated at a temperature of 550 ?C for the removal of organic groups. Each functionalization step was performed a new structure functionalization step, where they were repeated 6 times. The materials were characterized by physico-chemical techniques in order to verify the formation of structure and organization. The process of pure CO2 adsorption on functionalized SBA-16 materials, was performed on a volumetric equipment under 1 bar pressure at 45 ?C where the sample E-SBA16-10PEI and CC-SBA16-50PEI showing adsorption amounts of 47 mg CO2/g ads and 108 mg CO2/g ads, respectively. Adsorption tests for SBA-15 were also performed at 1 bar and 45 ? C, less amounts of CO2 absorbed were reported out for samples with DT and this is related to loss of efficiency of amines. This behavior was not observed in the samples impregnated with PEI.
13

An?lise do balan?o energ?tico e da matriz de emiss?es de poluentes no Estado do Rio Grande do Norte

Silveira, Th?zia Viviane Silva da 17 November 2008 (has links)
Made available in DSpace on 2014-12-17T14:52:41Z (GMT). No. of bitstreams: 1 ThaziaVSS.pdf: 623176 bytes, checksum: f3522bf5126d51241ee4b1cc03a0a3ad (MD5) Previous issue date: 2008-11-17 / This thesis intends to show the level of pollutant emissions in the State of Rio Grande do Norte, generated by the final consumption of energy in the many different sectors of the economy. This information was obtained from the energetic matrix and from the pollutant emissions of the State and the data was taken from the Balan?o Energ?tico Estadual and from the Sistema de Informa??es Energ?ticas da Olade. The result will permit to identify the energy and most polluting economic sectors in Rio Grande do Norte, contributing to energy planning, giving direction to the public policy development that aim at the change of the energy matrix of the State. Also with the objective of reducing pollutant emissions through rationalization, efficiency and energy substitution, which the main objective is to promote the economic development based on energy consumption of less harmful impact on the environment, contributing to establishment of sustainable development / A disserta??o pretende apresentar o n?vel de emiss?es em que se encontra o Estado do Rio Grande do Norte, geradas com o consumo final de energ?ticos nos diversos setores da economia. Esta informa??o foi obtida a partir da matriz energ?tica e de emiss?es poluentes do Estado, cujos dados foram extra?dos do Balan?o Energ?tico Estadual e do Sistema de Informa??es Energ?ticas da Olade. O resultado poder? identificar os energ?ticos e os setores econ?micos mais poluidores do RN, podendo auxiliar o planejamento energ?tico, direcionando o desenvolvimento de pol?ticas p?blicas que visam altera??o gradativamente da matriz energ?tica do RN com vistas ? redu??o de emiss?es poluentes atrav?s da racionaliza??o, efici?ncia e substitui??o energ?tica, cujo objetivo ? promover o desenvolvimento econ?mico, pautado no consumo de energia, de forma menos danosa ao meio ambiente, contribuindo tamb?m para o alcance de um desenvolvimento sustent?vel
14

A pegada de carbono como um dos indicadores de sustentabilidade para medi??o da responsabilidade socioambiental empresarial: um estudo de caso na unidade sede da Petrobras em Natal-RN / Carbon footprint as a sustainability indicator of corporative social-environmental responsibility measurement: a study case in seat unity of Petrobras at Natal-Brazil

Andrade, Ricardo Teixeira Greg?rio de 19 November 2010 (has links)
Made available in DSpace on 2014-12-17T14:52:57Z (GMT). No. of bitstreams: 1 RicardoTGA.pdf: 3343340 bytes, checksum: b7d667a5f20a1f26a7371755e94dcc8c (MD5) Previous issue date: 2010-11-19 / Instituto Federal de Educa??o, Ci?ncia e Tecnologia do Rio Grande do Norte / As a contemporary tendency, it is been evidenced that the environmental changes theme, already admitted as a concernment to international economical and political reality, is also gaining repercussion on industrial and business sector. Firms are implementing actions on trial to minimize their own greenhouse gases (GHG) emissions impacts. However, the great majority of those actions of Corporative Social-Environmental Responsibility (CSR) are referred only to direct emissions of the main production systems. Direct emissions are those derived of an isolate process, without considering the upstream and downstream processes emissions, which respond for the majority of emissions originated because of respective firm‟s production system existence. Because the greenhouse effect occurs globally and the GHG emissions contribute to the environmental changes independently of their origin, it must be taken into account the whole productive life cycle of products and systems, since the energy invested on resources extraction and necessary materials to the final disposal. To do so, it must be investigated all relevant steps of a product/production system life cycle, tracking all activities which emit greenhouse gases, directly or indirectly. This amount of emissions consists in the firm‟s Carbon Footprint. This research purpose is to defend the Carbon Footprint relevance and its adoption viability to be used as an Environmental Indicator on measurement/assessment of CSR. It has been realized a study case on Petrobras‟s seat unity at Natal-Brazil, assessing part of its Carbon Footprint. It has been used the software GEMIS 4.6 to do the emissions quantifying. The items measured were the direct emissions of the own unity vehicles and indirect emissions of offset paper (A4), energy and disposable plastic cups consumed. To 2009, these emissions were 3.811,94 tCO2eq. We may conclude that Carbon Footprint quantification is indispensable to the knowledge of real emissions caused by a productive process existence, must serving as basis to CSR decisions about the environmental changes reversion challenge / Contemporaneamente, se est? constatando que o tema das altera??es clim?ticas, j? integralizado como preocupa??o da realidade pol?tica e econ?mica internacional, vem tamb?m adquirindo abrang?ncia e repercuss?o nos setores industriais e empresariais. As empresas, em seu enquadramento no novo conceito de combate ? mudan?a do clima, t?m adotado algumas medidas na tentativa de minimizar os impactos das suas pr?prias emiss?es de Gases Efeito Estufa (GEE). Contudo, a grande maioria das a??es de Responsabilidade Socioambiental Empresarial (RSE) quanto a essa tem?tica referem-se apenas ?s emiss?es diretas dos principais processos produtivos empresariais. As emiss?es diretas s?o aquelas derivadas de um processo isolado, sem considerar os processos upstream e downstream, os quais respondem pela a maior parte das emiss?es derivadas da exist?ncia de uma determinada empresa. Haja vista que o efeito estufa sobrev?m de forma global, e que as emiss?es de GEE contribuem para as mudan?as clim?ticas independentemente de sua origem, deve-se levar em considera??o todo o ciclo de vida produtivo de produtos e processos, desde a energia investida na extra??o da mat?ria-prima e insumos necess?rios at? o descarte final. Para se fazer isso, deve-se esquadrinhar todos os passos relevantes ao longo do ciclo de vida de um produto/processo produtivo, rastreando todas as atividades que emitam direta ou indiretamente GEE. O somat?rio dessas consiste justamente na Pegada de Carbono da empresa. A finalidade desse estudo ? defender a relev?ncia da Pegada de Carbono e viabilidade de ado??o desta para ser usada como Indicador de Sustentabilidade na avalia??o/mensura??o da RSE. Para isso, foi realizado um estudo de caso na unidade sede da Petrobras em Natal-RN, avaliando-se parte de sua Pegada de Carbono. Para a quantifica??o das emiss?es, foi utilizado o software GEMIS 4.6. Os itens medidos foram as emiss?es diretas dos ve?culos pr?prios da unidade e emiss?es indiretas do papel offset A4, energia el?trica e copos pl?sticos descart?veis consumidos. Para o exerc?cio de 2009, mensuramos a emiss?o de 3.811,94 tCO2eq. Conclu?mos que a aferi??o da Pegada de Carbono ? imprescind?vel para conhecimento das emiss?es reais causadas pela exist?ncia de um processo produtivo, devendo servir de base para a tomada de decis?es de RSE quanto ao desafio da revers?o das mudan?as clim?ticas
15

?Formula??o de novos combust?veis base diesel: avalia??o de desempenho e emiss?es / Formulation of new diesel-based fuels: Evaluation of performance and emissions

Fernandes, Manoel Reginaldo 16 May 2011 (has links)
Made available in DSpace on 2014-12-17T15:01:52Z (GMT). No. of bitstreams: 1 ManoelRF_TESE_PARCIAL.pdf: 3699462 bytes, checksum: 4db868ae1dcdf8497e51d1aa5771684c (MD5) Previous issue date: 2011-05-16 / The industry, over the years, has been working to improve the efficiency of diesel engines. More recently, it was observed the need to reduce pollutant emissions to conform to the stringent environmental regulations. This has attached a great interest to develop researches in order to replace the petroleum-based fuels by several types of less polluting fuels, such as blends of diesel oil with vegetable oil esters and diesel fuel with vegetable oils and alcohol, emulsions, and also microemulsions. The main objective of this work was the development of microemulsion systems using nonionic surfactants that belong to the Nonylphenols ethoxylated group and Lauric ethoxylated alcohol group, ethanol/diesel blends, and diesel/biodiesel blends for use in diesel engines. First, in order to select the microemulsion systems, ternary phase diagrams of the used blends were obtained. The systems were composed by: nonionic surfactants, water as polar phase, and diesel fuel or diesel/biodiesel blends as apolar phase. The microemulsion systems and blends, which represent the studied fuels, were characterized by density, viscosity, cetane number and flash point. It was also evaluated the effect of temperature in the stability of microemulsion systems, the performance of the engine, and the emissions of carbon monoxide, nitrogen oxides, unburned hydrocarbons, and smoke for all studied blends. Tests of specific fuel consumption as a function of engine power were accomplished in a cycle diesel engine on a dynamometer bench and the emissions were evaluated using a GreenLine 8000 analyzer. The obtained results showed a slight increase in fuel consumption when microemulsion systems and diesel/biodiesel blends were burned, but it was observed a reduction in the emission of nitrogen oxides, unburned hydrocarbons, smoke index and f sulfur oxides / A ind?stria, ao longo dos anos, vem trabalhando no sentido de melhorar a efici?ncia dos motores. Mais recentemente surgiu, tamb?m, a necessidade de reduzir as emiss?es de poluentes para se adequar ?s severas leis ambientais. Isto tem despertado o interesse de desenvolver pesquisas no sentido de substituir os combust?veis derivados do petr?leo por diversos tipos de combust?veis menos poluentes, tais como: misturas de ?leo diesel com ?steres de ?leos vegetais e ?leo diesel com ?leos vegetais e ?lcool, emuls?es e microemuls?es. Este trabalho tem como objetivo desenvolver sistemas microemulsionados a partir de tensoativos n?o i?nicos dos grupos nonilfenois etoxilados e ?lcoois l?uricos etoxilados, misturas com etanol/diesel e misturas diesel/biodiesel para uso em motores diesel. Em uma primeira fase, visando selecionar os sistemas microemulsionados, foram obtidos diagramas tern?rios das misturas, sendo os sistemas compostos por: tensoativos n?o-i?nicos, ?gua como fase polar e como fase apolar o diesel e/ou misturas diesel/biodiesel. Os sistemas microemulsionados e as misturas, que representam os combust?veis estudados, foram caracterizados quanto ? massa espec?fica, a viscosidade, o ?ndice de cetano e o ponto de fulgor. Tamb?m foram avaliados o efeito da temperatura nos sistemas microemulsionados, o desempenho do motor, e as emiss?es de mon?xido de carbono, ?xidos de nitrog?nio, hidrocarbonetos n?o queimados e fuma?a de todos os sistemas. Os ensaios de consumo espec?fico e das emiss?es em fun??o da pot?ncia foram realizados em um motor de ciclo diesel em uma bancada dinamom?trica e o analisador de emiss?es GreenLine 8000. Os resultados mostraram um pequeno aumento no consumo espec?fico para os combust?veis microemulsionados, nas misturas diesel/biodiesel em rela??o ao diesel puro, por?m com uma redu??o nas emiss?es de ?xidos de nitrog?nio, hidrocarbonetos n?o queimados, ?ndice de fuma?a e ?xidos de enxofre
16

Quantifica??o das emiss?es de gases de efeito estufa para ve?culos de coleta de res?duos domiciliares abastecidos com GNV e Diesel-B5 utilizando avalia??o de ciclo de vida (ACV)

Costa, Ronaldo Silvestre da 30 November 2016 (has links)
Submitted by PPG Engenharia e Tecnologia de Materiais (engenharia.pg.materiais@pucrs.br) on 2018-02-19T14:21:21Z No. of bitstreams: 1 Tese RONALDO SILVESTRE DA COSTA Final Entrega PGETEMA.pdf: 3370134 bytes, checksum: 383fa921245f353cae4a408bd4641901 (MD5) / Approved for entry into archive by Caroline Xavier (caroline.xavier@pucrs.br) on 2018-02-23T17:34:28Z (GMT) No. of bitstreams: 1 Tese RONALDO SILVESTRE DA COSTA Final Entrega PGETEMA.pdf: 3370134 bytes, checksum: 383fa921245f353cae4a408bd4641901 (MD5) / Made available in DSpace on 2018-02-23T17:39:49Z (GMT). No. of bitstreams: 1 Tese RONALDO SILVESTRE DA COSTA Final Entrega PGETEMA.pdf: 3370134 bytes, checksum: 383fa921245f353cae4a408bd4641901 (MD5) Previous issue date: 2016-11-30 / Funda??o de Amparo ? Pesquisa do Estado do Rio Grande do Sul (FAPERGS) / The transport sector represents a significant responsibility in the pollution emissions. Also, the consumption of fossil fuels is related with the rising of global average temperature due to the greenhouse gas emissions. Biofuels and natural gas are investigated as alternative fuels to mitigate the environmental impacts. However, due to the several source emissions within a product life-cycle, the environmental performance of an environmental friendly product must be verified. This work aims to quantify greenhouse gas emissions during household waste collection by heavy vehicles (trucks) fueled with different fuels. It was proposed the development and implementation of a methodology to compare both pollutant gas emissions and noise for the use of CNG (compressed natural gas) and diesel-B5, aiming to mitigate environmental impacts in captive fleet that travels daily in the Porto Alegre city, Rio Grande do Sul state, Brazil. The trucks were monitored using a portable gas analyzer equipment (O2, CO, CO2, NO, NO2, NOx, SO2, HC), and the fuel consumptions and autonomy were obtained from the company that provides the service. With the data collected on established routes, it was applied the Life Cycle Assessment (LCA) methodology to carry out the study comparing the environmental performance of the use of CNG and Diesel-B5. The results showed that higher global warming impact (according IPCC method) was observed to CNG, independently of the time horizon considered (20 100 or 500 years). When comparing the contribution of the process stages (from production to use of fuels), CNG presented higher impacts in the collection and venting steps, while diesel -- B5 presented in the collection step. / O setor de transportes apresenta significativos problemas ambientais relacionados ?s emiss?es de poluentes, agravados em regi?es urbanas. A queima e a explora??o de combust?veis f?sseis s?o constantemente relacionadas ao aumento da temperatura m?dia global. O uso de combust?veis, como os de origem vegetal e g?s natural, tem sido uma alternativa frequente na mitiga??o de gases de efeito estufa. No entanto, devido ?s v?rias fontes de poluentes presentes no ciclo de vida do produto, o desempenho ambiental de produtos considerados amig?veis ao meio ambiente deve ser verificado. Este trabalho teve como objetivo quantificar as emiss?es de gases de efeito estufa emitidos durante a coleta de res?duos domiciliares por ve?culos pesados (caminh?es) abastecidos com diferentes combust?veis: g?s natural e diesel-B5. Prop?e-se o desenvolvimento e a implementa??o de uma metodologia para a compara??o das emiss?es de poluentes para o uso de GNV (g?s natural veicular) e Diesel-B5, objetivando a mitiga??o de impactos ambientais em frota cativa que trafega diariamente na cidade de Porto Alegre ? RS. Os caminh?es foram monitorados com um equipamento analisador port?til de gases (O2, CO, CO2, NO, NO2, NOx, SO2, HC), e os consumos e a autonomia dos combust?veis foram obtidos junto ? empresa prestadora do servi?o. Com os dados levantados nas rotas estabelecidas, foi aplicada a metodologia de Avalia??o do Ciclo de Vida (ACV) para realizar o estudo de compara??o do desempenho ambiental entre o uso de GNV e Diesel-B5, considerando todas as etapas desde a produ??o at? o consumo final dos combust?veis. Os resultados mostraram que o maior potencial para aquecimento global (segundo o m?todo IPCC) ocorre para o GNV, considerando per?odos de 20 anos, 100 anos e 500 anos. Quando comparadas as contribui??es das diferentes etapas do processo, desde a produ??o at? o uso do combust?vel, observou-se que o GNV apresenta os maiores impactos nas etapas de transporte e coleta de res?duos, enquanto o Diesel-B5 apresenta impacto significativo apenas na etapa de coleta de res?duos.
17

An?lise de campos eletromagn?ticos em edifica??es urbanas.

Coiado, Lorenzo Campos 11 December 2015 (has links)
Made available in DSpace on 2016-04-04T18:24:59Z (GMT). No. of bitstreams: 1 Lorenzo Campos Coiado.pdf: 6103508 bytes, checksum: c9033d87024f0bd094c3b96518ddfa4d (MD5) Previous issue date: 2015-12-11 / This work presents an analysis of the electromagnetic field in urban buildings having as motivation the search for buildings sustainability. The study of certifications that evaluate buildings environmental performance raises the need to study the electromagnetic fields, which is considered one factor of human comfort. The study of electromagnetic fields allows the development of analytical methodologies of the "Field Energy? (around 60 Hz) and "Field Communication" (with frequencies in the range between 915 MHz and 2.4 GHz). The analysis of the emissions makes possible to identify the sources causing electromagnetic emissions and their mitigation. As sustainability solution, it was developed a non-destructive sensor for monitoring the energy efficiency of buildings, enabling a simple and inexpensive solution to assess the energy consumption of a building without destroying existing installations. / Este trabalho apresenta uma an?lise das emiss?es de campos eletromagn?ticos em edifica??es urbanas tendo como motiva??o a busca pela sustentabilidade de edifica??es. O estudo de certifica??es que avaliam o desempenho ambiental real?ou a necessidade de estudar os campos eletromagn?ticos dispersos no ar, sendo este um dos fatores de conforto humano. O estudo dos campos eletromagn?ticos permite o desenvolvimento de metodologias de an?lise do ?Campo Energia? (com frequ?ncia em torno de 60 Hz) e ?Campo Telecomunica??es? (com frequ?ncias na faixa entre 915 MHz e 2.4GHz). A an?lise das emiss?es torna poss?vel identificar onde est?o localizadas as fontes causadoras das emiss?es eletromagn?ticas e possibilita sua mitiga??o. Como solu??o de sustentabilidade foi desenvolvido um sensor n?o destrutivo para monitoramento da efici?ncia energ?tica de edifica??es, possibilitando uma solu??o simples e barata para o levantamento do consumo de energia de uma edifica??o sem destruir constru??es j? existentes.
18

An?lise do desempenho de um queimador infravermelho funcionando com g?s liquefeito de petr?leo e glicerina

Dantas, Marcello Ara?jo 31 May 2010 (has links)
Made available in DSpace on 2014-12-17T14:08:39Z (GMT). No. of bitstreams: 1 MarcelloAD_DISSERT.pdf: 3032114 bytes, checksum: 1b49aa6af338e06fe387bb398cc85b4b (MD5) Previous issue date: 2010-05-31 / The use of infrared burners in industrial applications has many advantages in terms of technical-operational, for example, uniformity in the heat supply in the form of radiation and convection, with greater control of emissions due to the passage of exhaust gases through a macro-porous ceramic bed. This paper presents an infrared burner commercial, which was adapted an experimental ejector, capable of promoting a mixture of liquefied petroleum gas (LPG) and glycerin. By varying the percentage of dual-fuel, it was evaluated the performance of the infrared burner by performing an energy balance and atmospheric emissions. It was introduced a temperature controller with thermocouple modulating two-stage (low heat / high heat), using solenoid valves for each fuel. The infrared burner has been tested and tests by varying the amount of glycerin inserted by a gravity feed system. The method of thermodynamic analysis to estimate the load was used an aluminum plate located at the exit of combustion gases and the distribution of temperatures measured by a data acquisition system which recorded real-time measurements of the thermocouples attached. The burner had a stable combustion at levels of 15, 20 and 25% of adding glycerin in mass ratio of LPG gas, increasing the supply of heat to the plate. According to data obtained showed that there was an improvement in the efficiency of the 1st Law of infrared burner with increasing addition of glycerin. The emission levels of greenhouse gases produced by combustion (CO, NOx, SO2 and HC) met the environmental limits set by resolution No. 382/2006 of CONAMA / A utiliza??o de queimadores infravermelhos em aplica??es industriais apresenta muitas vantagens do ponto de vista t?cnico-operacional, como por exemplo, homogeneidade no fornecimento de calor, na forma de radia??o e convec??o, apresentando um maior controle das emiss?es devido ? passagem dos gases de exaust?o atrav?s de um leito cer?mico macroporoso. O presente trabalho apresenta um queimador infravermelho comercial, no qual foi adaptado um ejetor experimental, capaz de promover uma mistura de g?s liquefeito de petr?leo (GLP) e glicerina. Atrav?s da varia??o de percentuais de combust?vel dual, foi avaliado o desempenho do queimador infravermelho mediante a realiza??o de um balan?o de energia e das emiss?es atmosf?ricas. Foi introduzido um controlador de temperatura com termopar modulando dois est?gios (fogo baixo/alto), utilizando v?lvulas solen?ides para cada combust?vel. O queimador infravermelho foi submetido a testes e ensaios variando-se a quantidade de glicerina inserida por um sistema de alimenta??o por gravidade. Como m?todo de an?lise termodin?mica para estimativa de carga foi utilizada uma placa de alum?nio localizada na sa?da dos gases de combust?o, sendo a distribui??o de temperaturas medida por um sistema de aquisi??o de dados que registrou em tempo real as medidas dos termopares afixados. O queimador apresentou uma combust?o est?vel para os n?veis de 15, 20 e 25 % de adi??o de glicerina em raz?o m?ssica de GLP, aumentando o fornecimento de calor para a placa. Pelos dados obtidos, observou-se que houve uma melhora na efici?ncia de 1? Lei do queimador infravermelho quando ocorre o aumento de adi??o da glicerina na mistura. Os n?veis de emiss?es de gases poluentes produzidos pela combust?o (CO, NOx, SO2 e HC) atenderam aos limites estabelecidos pela resolu??o ambiental n? 382/ 2006 do CONAMA.
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An?lise estat?stica das emiss?es de CO e HC produzidas por gases da exaust?o veicular oriundos de gasolina, GNV e mistura ?lcool/gasolina

Fernandes, C?liton de Souza 13 July 2009 (has links)
Made available in DSpace on 2014-12-17T14:57:49Z (GMT). No. of bitstreams: 1 CelitonS.pdf: 1872654 bytes, checksum: 0e3a2fa3a25b2b0d3f6314fb9f1b6ab9 (MD5) Previous issue date: 2009-07-13 / The vehicles are the main mobile sources of carbon monoxide (CO) and unburned hydrocarbons (HC) released into the atmosphere. In the last years the increment of the fleet of vehicles in the municipal district of Natal-RN it is contributing to the increase of the emissions of those pollutants. The study consisted of a statistical analysis of the emissions of CO and HC of a composed sample for 384 vehicles with mechanization Gasoline/CNG or Alcohol/Gasoline/CNG of the municipal district of Natal-RN. The tests were accomplished in vehicles submitted to Vehicular Safety's Inspection, in the facilities of INSPETRANS, Organism of Vehicular Inspection. An partial gases analyzer allowed to measure, for each vehicle, the levels of CO and HC in two conditions of rotation of the motor (900 and 2500 rpm). The statistical analysis accomplished through the STATISTICA software revealed a sensitive reduction in the efficiency of the converters catalytic after 6 years of use with emission average it is of 0,78% of CO and 156 (ppm) of HC, Which represents approximately 4 (four) times the amount of CO and the double of HC in comparison with the newest vehicles. The result of a Student s t-test, suggests strongly that the average of the emissions of HC (152 ppm), at 900 rpm, is 40% larger than at 2500 rpm, for the motor without load. This result reveals that the efficiency of the catalytic conversion is limited kinetically in low engine speeds. The Study also ends that when comparing the emissions of CO and HC considering the influence of the fuels, it was verified that although the emissions of CO starting from CNG are 62% smaller than arising from the gasoline, there are not significant differences among the emissions of HC originating from of CNG and of the gasoline. In synthesis, the results place the current criteria of vehicular inspection, for exhaust gases, in doubt, leading the creation of emission limits of pollutant more rigorous, because the efficiency of the converters catalytic is sensibly reduced starting from 6 years of use. It is also raised the possibility of modifications in the test conditions adopted by the current norms, specifically in the speed engine, have seen that in the condition without load the largest emission indexes were registered in slow march. That fact that allows to suggest the dismissal of the tests in high speed engine, reducing the time of inspection in half and generating economy of fuel / Os ve?culos automotores s?o as principais fontes m?veis de Mon?xido de Carbono (CO) e Hidrocarbonetos n?o queimados (HC) lan?ados na atmosfera. Nos ?ltimos anos o acr?scimo da frota de ve?culos no munic?pio de Natal-RN vem contribuindo para o aumento das emiss?es desses gases poluentes. O estudo consistiu de uma an?lise estat?stica das emiss?es de CO e HC de uma amostra composta por 384 ve?culos com motoriza??o a Gasolina/GNV ou ?lcool/Gasolina/GNV do munic?pio de Natal-RN. Os testes foram realizados em ve?culos submetidos ? Inspe??o de Seguran?a Veicular, nas instala??es do INSPETRANS, Organismo de Inspe??o Veicular. Um analisador de gases parcial permitiu medir, para cada ve?culo, os n?veis de CO e HC em duas condi??es de rota??o do motor (900 e 2500 rpm). A an?lise estat?stica realizada por meio do software STATISTICA revelou uma sens?vel redu??o na efici?ncia dos conversores catal?ticos ap?s 6 anos de uso com a emiss?o m?dia de 0,78 % de CO e 156 (ppm) de HC, o que representa aproximadamente 4 (quatro) vezes a quantidade de CO e o dobro de HC em compara??o com os ve?culos mais novos. O resultado de um Teste-T de Student sugere fortemente que a m?dia das emiss?es de HC (152 ppm), a 900 rpm, ? 40% maior que a 2500 rpm, para o motor sem carga. Esse resultado revela que a efici?ncia da convers?o catal?tica ? limitada cineticamente em baixas rota??es. O Estudo conclui tamb?m que ao comparar as emiss?es de CO e HC, considerando a influ?ncia dos combust?veis, verificou-se que embora as emiss?es de CO a partir do GNV sejam 62% menores do que a partir da gasolina, n?o h? diferen?as significativa entre as emiss?es de HC oriundas do GNV e da gasolina. Em s?ntese, os resultados colocam os atuais crit?rios de inspe??o veicular, para gases da exaust?o, em d?vida, conduzindo a cria??o de limites de emiss?o de poluentes mais rigorosos, visto que a efici?ncia dos conversores catal?ticos ? sensivelmente reduzida a partir de 6 anos de uso. Suscita-se tamb?m a possibilidade de modifica??es nas condi??es de teste adotadas pelas normas atuais, especificamente na rota??o do motor, haja vista que na condi??o sem carga os maiores ?ndices de emiss?o foram registrados em marcha lenta. De ante disso, sugere-se a dispensa dos testes em altas rota??es, reduzindo ? metade o tempo de inspe??o e gerando economia de combust?vel
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An?lise das emiss?es atmosf?ricas por ve?culos automotores em Natal-RN

Brito, Herm?nio Pereira de 11 November 2005 (has links)
Made available in DSpace on 2014-12-17T14:58:11Z (GMT). No. of bitstreams: 1 HerminioPB.pdf: 3768069 bytes, checksum: 694372597a20b234c0403ab08b7bc801 (MD5) Previous issue date: 2005-11-11 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The fast urban occupation of Brazil, mainly from the last decade of 50, a sensible degradation of the quality of the air generated mainly for the activities was verified human beings associates to industrialization. From the past years, the situation has gotten worst in function of the increment of the fleet of vehicles in circulation in the great cities. Being these, in the city of Natal-RN, the ones that offer the biggest contributions to the atmospheric pollution. For atmospheric air to be a finite natural resources, indispensable and essential to the maintenance of the life in the land, is necessary to the implementation of action to improve its quality and to protect the health of the population. With the objective to study relative aspects to the characteristics of vehicles in use, the present study it searchs to analyze the levels of emissions of gases generated for vehicles converted bi-fuels into the modalities: natural gas (GNV), gasoline and alcohol, inspected for ends of register and together licensing to the State Department of Transit. One used the data gotten from inspections carried through for the company System Specialized in Inspection To propagate, in the city of the Natal-RN, capital of the State of Rio Grande do Norte, between 14 of November of 2003 and 30 of December of 2004. The analyzed parameters are established in the resolution n? 07/93 CONAMA. Of a total of 1.517 inspected vehicles, a average of 15,2% of failed was gotten, or either, that they emit levels of pollution above of the limits established for the legislation, below of the national average that is of 20,0%. The analysis of the data discloses that 7.3% of the fleet are converted the GNV; the growth of vehicles converted the GNV into the city is gradual, with a average of increment in last the 4 years of 23,3%; it has a vehicle predominance that has as combustible original to the gasoline (88,2%); the inspected fleet has average age of 8 years of use, considered young for the Brazilian standards, except for the moved one to the alcohol (average of use of 15 years). Moreover, the type of fuel is not the main parameter to define the indices of emissions; the age of the fleet is the parameter most important when emission is analyzed to propagate; the gas that more generates failed in the inspections is the corrected carbon monoxide; the vehicles generate higher indices of emissions in idling for all the fuels; the presence of the catalyser was not reflected, as it expected, in the reduction of emissions of gases toxic, however when analyzed according to year of manufacture, it was observed that for the vehicles manufactured between 1997 and 2004, reduction of 46,0% in the failed of the vehicles equipped with catalyser was gotten. In conclusion, the fleet of the studied sample, in average terms, takes care of to the requirements of Resolution CONAMA n? 07/93. The results gotten for the present study can subsidize action of public administrations that aim at to the improvement and the maintenance of the quality of air in the city of Natal-RN, as, for example, to implant a net of monitoramento of the quality of air / Com a r?pida ocupa??o urbana do Brasil, notadamente a partir da ?ltima d?cada de 50, verificou-se uma sens?vel degrada??o da qualidade do ar gerada principalmente pelas atividades humanas associadas ? industrializa??o. Ao longo dos anos, esta situa??o tem se agravado em fun??o do incremento da frota de ve?culos automotores em circula??o nas grandes cidades. Sendo estes, na cidade de Natal-RN, os que oferecem as maiores contribui??es ? polui??o atmosf?rica. Pelo ar atmosf?rico ser um recurso natural finito, indispens?vel e essencial ? manuten??o da vida na terra, ? necess?ria ? implementa??o de a??es para melhorar sua qualidade e proteger a sa?de da popula??o. Com o objetivo de estudar aspectos relativos as caracter?sticas de ve?culos automotores em uso, o presente estudo busca analisar os n?veis de emiss?es de gases gerados por ve?culos automotores convertidos a bi-combust?veis nas modalidades: G?s Natural Veicular, Gasolina e ?lcool, inspecionados para fins de registro e licenciamento junto ao Departamento Estadual de Tr?nsito do Rio Grande do Norte. Utilizaram-se os dados obtidos a partir de inspe??es realizadas pela empresa Sistema Especializado em Inspe??o Veicular, na cidade do Natal, capital do Rio Grande do Norte, entre os dias 14 de novembro de 2003 e 30 de dezembro de 2004. Os par?metros analisados foram os estabelecidos na resolu??o n? 07/93 CONAMA. De um total de 1.517 ve?culos inspecionados, obteve-se uma m?dia de 15,2% de reprova??o, ou seja, que emitem n?veis de polui??o acima dos limites estabelecidos pela legisla??o, abaixo da m?dia nacional que ? de 20,0%. A an?lise dos dados revela que 7,3% da frota ? convertida a GNV; o crescimento da frota de ve?culos convertidos a GNV na cidade, ? progressivo, com uma m?dia de incremento nos ?ltimos 4 anos de 23,3%; h? um predom?nio de ve?culos que t?m como combust?vel original a gasolina (88,2%); a frota inspecionada tem idade m?dia de 8 anos de uso, considerada jovem para os padr?es brasileiros, exceto para a movida ? ?lcool (m?dia de uso 15 anos). Al?m disso, tipo de combust?vel n?o ? o principal par?metro para se definir os ?ndices de emiss?es; a idade da frota ? o par?metro mais importante quando se analisa emiss?o veicular; o g?s que mais gera reprova??o nas inspe??es ? o mon?xido de carbono corrigido; os ve?culos geram ?ndices mais elevados de emiss?es em marcha lenta para todos os combust?veis; a presen?a do catalisador n?o se refletiu, como se esperava, na redu??o de emiss?es de gases t?xicos, por?m quando analisado segundo o ano de fabrica??o, observou-se que para os ve?culos fabricados entre 1997 e 2004, houve uma redu??o de 46,0% nas reprova??es dos ve?culos equipados com catalisador. Em conclus?o, a frota estudada em m?dia atende as exig?ncias da Resolu??o CONAMA n? 07/93. Os resultados apresentados no presente estudo podem subsidiar a??es de gest?es p?blicas que visem ? melhoria e a manuten??o da qualidade do ar na cidade de Natal, como, por exemplo, implantar uma rede de monitoramento da qualidade do ar

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