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

Estudo de remoção de elementos inorgânicos e degradação de compostos orgânicos por radiação gama em óleos lubrificantes usados / Inorganic elements and organic compounds degradation studies by gamma irradiation in used lubricating oils

SCAPIN, MARCOS A. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:54:39Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:07:58Z (GMT). No. of bitstreams: 0 / Os óleos lubrificantes automotivos durante o seu uso sofrem degradação parcial de compostos orgânicos e incorporam elementos inorgânicos indesejáveis. Estas substâncias tornam o óleo lubrificante usado classificado como perigoso e altamente tóxico. Assim, no que diz respeito à conservação ambiental, o consenso mundial é que a melhor solução para os óleos lubrificantes usados objetive no tratamento para a sua reutilização. Dentro deste contexto e visando o uso de uma tecnologia alternativa, neste trabalho foi proposto um estudo sobre a eficiência e a viabilidade técnica do processo de oxidação avançada (POA) por radiação gama para o tratamento de óleo lubrificante automotivo usado. Amostras de óleo lubrificante usado foram diluídas em concentrações variadas com peróxido de hidrogênio e água Milli-Q. Estas amostras foram submetida a um irradiador de Cobalto-60, tipo Gammacell, com as doses absorvidas de 100, 200 e 500 kGy. Os resultados das análises inorgânicas por fluorescência de raios X (WDXRF) mostraram que o tratamento proposto permite a remoção de elementos inorgânicos, principalmente enxofre, cálcio, ferro e níquel em níveis aceitáveis pela legislação ambiental para reuso destes óleos. Os resultados por cromatografia gasosa (CG/MS) mostraram que este tratamento, também, promove a degradação dos compostos orgânicos, formando principalmente, os compostos tridecano, 2-metil-naftaleno, trietilamina e uréia-tetrametil, os quais são de grande aplicação industrial. A análise multivariada, análise de Cluster (CA), confirmou que a aplicação POA é um tratamento promissor e viável para o reuso de óleo lubrificante usado. INORGANIC / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
72

Estudo da contaminacao do solo e agua subterranea por elementos toxicos originados dos rejeitos das minas de carvao de Figueira no Estado do Parana

SHUQAIR, SHUQAIR M.S. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:47:19Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:10:26Z (GMT). No. of bitstreams: 1 08354.pdf: 6557210 bytes, checksum: 0c6cea793150b2683fda13b9ec421168 (MD5) / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
73

Nitrous oxide and methane emissions from agriculture and approaches to mitigate greenhouse gas emissions from livestock production

Webb, J. January 2017 (has links)
This thesis links papers reporting field measurements, modelling studies and reviews of greenhouse gas (GHG) emissions and their abatement from agriculture, in particular from livestock production. The aims of the work were to: quantify GHG emissions from litter-based farmyard manures; evaluate means by which GHG emissions from agricultural production may be abated; assess synergies and conflicts between the abatement of other N pollutants on emissions of nitrous oxide (N2O); analyse two records of soil temperature from 1976-2010 from Wolverhampton (UK) and Vienna (Austria). Agricultural emissions of GHGs are not readily abated by ‘end of pipe’ technologies. Large decreases in agricultural GHG emissions may require changes in the production and consumption of food that could have unwelcome impacts on both consumers and producers. However, identifying and prioritizing both modes and locations of production, together with utilizing inputs, such as N fertilizer and livestock feeds, more efficiently can reduce GHG emissions while maintaining outputs. For example, GHG emissions from livestock production may be lessened by increasing the longevity of dairy cows, thereby decreasing the proportion of unproductive replacement animals in the dairy herd. Sourcing a larger proportion of calves from the dairy herd would decrease emissions of GHGs from beef production. The distance between the region of food production to that of consumption has relatively little impact on total GHG emissions per tonne of food product. Due to greater productivity or lesser energy inputs, importing some foods produced in other parts of the world may decrease GHG emissions per tonne compared with UK production, despite the additional emissions arising from long-distance transport. Manure application techniques to abate ammonia (NH3) emissions do not axiomatically increase emissions of N2O and may decrease them. Soil temperature measurements from 1976 to 2010 were consistent with the warming trends reported over the last 40 years.
74

Análise de aproveitamento energético em aterros sanitários baseada em cenários de produção de efluentes

Thomazoni, André Luis Ribeiro January 2014 (has links)
O aumento da preocupação de soluções ambientalmente adequadas e energeticamente eficientes, aliado às recentes mudanças nas diretrizes políticas Brasileiras em relação à gestão e ao gerenciamento de resíduos sólidos e suas práticas de disposição final, permite a oportunidade de investigar a recuperação energética e o abatimento dos efluentes gerados por aterros sanitários. O presente trabalho explora, separadamente, o uso de modelo de previsão de produção de biogás baseado no decaimento de primeira ordem, e para a estimativa de produção de lixiviado, aplica-se o método do balanço hídrico (MBH). A partir de variação dos principais parâmetros de entrada de cada modelo, obtêm-se cenários de produção de biogás e estimativas da capacidade de geração máxima e mínima de lixiviado para o aterro sanitário de Guajuviras (Canoas - RS, Brasil). Tomando os resultados de geração de lixiviado e de biogás calculados, estima-se o potencial energético disponível e o desempenho de três diferentes sistemas de conversão energética propostos: geração elétrica por motogeradores, evaporação de lixiviado em regime de cogeração com motogeradores, motogeradores com trocadores de calor em regime de cogeração e sistema de evaporação de lixiviado (LES). Resultados obtidos para o período analisado, mostram que a produção elétrica do cenário mais conservador está na faixa entre 17.300 a 18.800 MWh, enquanto que a produção de energia elétrica do cenário otimista atinge valores entre 416.976 e 459.900 MWh. Já para a evaporação de lixiviado, os volumes evaporados em regime de cogeração variaram de 1 a 70% em relação ao volume de lixiviado gerado pelo aterro sanitário, enquanto que o LES, considerando o cenário otimista, foi capaz de evaporar 100% do lixiviado durante 18 anos. / The growing concern on environmentally suitable and energy efficient solutions allied with the recent changes in the Brazilian policies on the solid waste management and its final disposal practices, enables an opportunity to investigate the energy recovery and abatement of landfills emissions. The present work explores separately the utilization of 1st order decay model for assess the landfill gas (LFG) production, and applies the water budget method for prediction of leachate generation. Ranging the main input parameters on each model, were obtained distinct scenarios for LFG production and the maximum and minimum leachate generation capacity of Guajuviras landfill (Canoas- RS, Brazil). Based in the calculated results for leachate and LFG production were assessed the available energetic potential and the performance of three distinct energetic conversion systems: motogenerators, heat exchangers in cogeneration with motogenerators and leachate evaporation system (LES). Results for the analyzed period show that the electric generation for conservative scenario ranges between 17.300 to 18.800 MWh, whereas, the electricity production for more optimistic scenario ranges between 416.976 to 459.900 MWh. As for the leachate evaporation, the evaporated volume by the cogeneration system reaches values between 1 to 70% of the leachate produced by the landfill, whereas, the LES, considering the optimistic scenario, is able to evaporate all the generated leachate by the landfill among 18 years.
75

Evaluation of heat abatement use, vaginal temperature, and activity of pregnant, lactating Holstein cows housed on pasture with or without the choice between shade and sprinklers for heat abatement.

Braman, Kevin M. 08 August 2023 (has links) (PDF)
The objective of this thesis was to determine how pregnant, lactating Holstein cows on pasture interact with shade and sprinklers when offered a choice or no-choice between methods. Authors hypothesized that cows would use shade more then sprinklers, but sprinklers would be more effective at cooling cows. Additionally, authors predicted cows using shade more would have decreased lying bouts and steps and an increase in time lying, compared to cows choosing sprinkler. Results indicate cows will use both methods when offered alone or together. However, cows will choose to be exposed or in shade at lower temperature humidity index values, but as the heat load increases, cows will shift to using sprinkler just as much as shade, and decrease overall time exposed. Overall, sprinklers were more effective at reducing vaginal temperature in heat stressed cows on pasture. Cows in shade had decreased lying bouts and steps, and increased time lying.
76

Residential property tax abatement: Testing a model of neighborhood impact

Swetkis, Doreen 30 November 2009 (has links)
No description available.
77

Determination of Scope 1 Greenhouse Gas Emissions in High-Frequency Filter Production

Paukner, Maximilian January 2024 (has links)
In the electronics industry, several greenhouse gases (GHGs) are used as process gases in manufacturing processes. The organization RF360 as a Qualcomm Inc. subsidiary is using GHGs as input gases in the manufacturing processes dry etching, Chemical Vapor Deposition (CVD) and trimming in the fabrication plant in Munich.The estimation of GHG emissions from the use of process gases under Scope 1 requires a global and comprehensive approach to determine emission sources. This work provides the basis for the GHG emission estimation from process gas use under consideration of the 2019 Refinement to the 2006 IPCC Guidelines for National Greenhouse Gas Inventories. Dry etching and CVD process GHG emissions arecalculated using the Tier 2c method with process specific default emission factors. The process GHG emissions from trimming are characterized under Tier 3a, by determination of site-specific process emission factors. These emission factors are obtained from FTIR measurements in the inline. The measurement results show the input gas NF3 is largely not converted or destroyed in the trimming process. The total GHG emissions resulting from process gas use in the considered processes are determined by emissions of NF3, CF4 and N2O. The implementation and improvement of the approach requires further measurements of site-specific emission factors in the processes and Destruction Removal Efficiencies of the abatement systems.
78

Metodologia para adaptação de curvas de custo marginal de abatimento / Methodology for adapting marginal abatement cost curves

Rodrigues, Paula Fernanda Morais Andrade 19 March 2018 (has links)
O Acordo de Paris preconiza que cada país descreva e comunique suas ações climáticas pós-2020. Neste contexto, as Curvas de Custo Marginal de Abatimento (MACC) podem ser úteis aos países e aos tomadores de decisão, pois mostram de forma clara o custo (em unidades monetárias por massa de CO2e) para a implementação de tecnologias de mitigação de emissões de gases do efeito estufa (GEE) e o seu potencial de redução de emissões associado (em massa de CO2e). As MACC podem ser utilizadas para qualquer unidade política, como: país, cidade ou estado. Podem, também, ser aplicadas a diversas áreas, tais como: transporte, construção, poluição do ar, agricultura ou indústria. Diante desta diversidade de estudos e aplicações, o objetivo do presente trabalho foi desenvolver uma metodologia de adaptação de MACC, de estudos publicados na literatura, para qualquer unidade política ou ano de interesse. Isto permitirá a \"reutilização\" destas MACC, porém sem a necessidade da realização de novos estudos. O desenvolvimento da metodologia de adaptação prescindiu de uma meta-análise e harmonização de dados da literatura. A metodologia desenvolvida foi aplica ao Brasil, considerando os subsetores industriais de cimento e de siderurgia. Ela foi, também, implementada no software Access® (e denominada re-MACC) para que todo o processo de adaptação das MACC pudesse ser realizado automaticamente. Analisando um total de 178 tecnologias de baixo carbono para os subsetores de cimento e de siderurgia, o resultado mostrou que seria possível reduzir, em 2014, aproximadamente 52,4% das emissões de CO2e, gerando uma economia monetária de 1.835 US$/tCO2e, caso o Brasil as adotasse. A metodologia foi capaz de harmonizar dados para qualquer unidade política ou ano de interesse, todavia refinamentos são necessários para torná-la ainda mais acurada / The Paris Agreement calls on each country to describe and report on its climate actions post-2020. In this context, the Marginal Abatement Cost Curves (MACC) can be useful to countries and decision makers as they clearly show the cost (in monetary units per mass of CO2e) for the implementation of greenhouse gas (GHG) emission mitigation technologies and their associated emission reduction potential (in mass of CO2e). They can be used for any jurisdiction, such as country, city or state. They can also be applied to several areas, such as: transportation, buildings, air pollution, agriculture or manufacturing. In view of this diversity of studies and applications, the objective of the present work was to develop a methodology for adapting MACC, from studies published in the literature, to any jurisdiction or year of interest. This work allows for \"re-using\" these MACC, but without the need for new studies. The development of the methodology is based on a meta-analysis and harmonization of literature data. The methodology was applied to Brazil, considering the industrial cement and steel subsectors. It was implemented in the Access® software (and called re-MACC) so the MACC adaptation process could be performed automatically. Analyzing a total of 178 low-carbon technologies for the Brazilian industrial subsectors of cement and steel, the result showed that it would be possible to reduce by approximately 52.4% of CO2e emissions by 2014, generating monetary savings of 1,835 US$/tCO2e. The methodology proved to be capable in harmonizing the data, however further refinements are needed to make it even more accurate
79

Metodologia para adaptação de curvas de custo marginal de abatimento / Methodology for adapting marginal abatement cost curves

Paula Fernanda Morais Andrade Rodrigues 19 March 2018 (has links)
O Acordo de Paris preconiza que cada país descreva e comunique suas ações climáticas pós-2020. Neste contexto, as Curvas de Custo Marginal de Abatimento (MACC) podem ser úteis aos países e aos tomadores de decisão, pois mostram de forma clara o custo (em unidades monetárias por massa de CO2e) para a implementação de tecnologias de mitigação de emissões de gases do efeito estufa (GEE) e o seu potencial de redução de emissões associado (em massa de CO2e). As MACC podem ser utilizadas para qualquer unidade política, como: país, cidade ou estado. Podem, também, ser aplicadas a diversas áreas, tais como: transporte, construção, poluição do ar, agricultura ou indústria. Diante desta diversidade de estudos e aplicações, o objetivo do presente trabalho foi desenvolver uma metodologia de adaptação de MACC, de estudos publicados na literatura, para qualquer unidade política ou ano de interesse. Isto permitirá a \"reutilização\" destas MACC, porém sem a necessidade da realização de novos estudos. O desenvolvimento da metodologia de adaptação prescindiu de uma meta-análise e harmonização de dados da literatura. A metodologia desenvolvida foi aplica ao Brasil, considerando os subsetores industriais de cimento e de siderurgia. Ela foi, também, implementada no software Access® (e denominada re-MACC) para que todo o processo de adaptação das MACC pudesse ser realizado automaticamente. Analisando um total de 178 tecnologias de baixo carbono para os subsetores de cimento e de siderurgia, o resultado mostrou que seria possível reduzir, em 2014, aproximadamente 52,4% das emissões de CO2e, gerando uma economia monetária de 1.835 US$/tCO2e, caso o Brasil as adotasse. A metodologia foi capaz de harmonizar dados para qualquer unidade política ou ano de interesse, todavia refinamentos são necessários para torná-la ainda mais acurada / The Paris Agreement calls on each country to describe and report on its climate actions post-2020. In this context, the Marginal Abatement Cost Curves (MACC) can be useful to countries and decision makers as they clearly show the cost (in monetary units per mass of CO2e) for the implementation of greenhouse gas (GHG) emission mitigation technologies and their associated emission reduction potential (in mass of CO2e). They can be used for any jurisdiction, such as country, city or state. They can also be applied to several areas, such as: transportation, buildings, air pollution, agriculture or manufacturing. In view of this diversity of studies and applications, the objective of the present work was to develop a methodology for adapting MACC, from studies published in the literature, to any jurisdiction or year of interest. This work allows for \"re-using\" these MACC, but without the need for new studies. The development of the methodology is based on a meta-analysis and harmonization of literature data. The methodology was applied to Brazil, considering the industrial cement and steel subsectors. It was implemented in the Access® software (and called re-MACC) so the MACC adaptation process could be performed automatically. Analyzing a total of 178 low-carbon technologies for the Brazilian industrial subsectors of cement and steel, the result showed that it would be possible to reduce by approximately 52.4% of CO2e emissions by 2014, generating monetary savings of 1,835 US$/tCO2e. The methodology proved to be capable in harmonizing the data, however further refinements are needed to make it even more accurate
80

Back-calculating emission rates for ammonia and particulate matter from area sources using dispersion modeling

Price, Jacqueline Elaine 15 November 2004 (has links)
Engineering directly impacts current and future regulatory policy decisions. The foundation of air pollution control and air pollution dispersion modeling lies in the math, chemistry, and physics of the environment. Therefore, regulatory decision making must rely upon sound science and engineering as the core of appropriate policy making (objective analysis in lieu of subjective opinion). This research evaluated particulate matter and ammonia concentration data as well as two modeling methods, a backward Lagrangian stochastic model and a Gaussian plume dispersion model. This analysis assessed the uncertainty surrounding each sampling procedure in order to gain a better understanding of the uncertainty in the final emission rate calculation (a basis for federal regulation), and it assessed the differences between emission rates generated using two different dispersion models. First, this research evaluated the uncertainty encompassing the gravimetric sampling of particulate matter and the passive ammonia sampling technique at an animal feeding operation. Future research will be to further determine the wind velocity profile as well as determining the vertical temperature gradient during the modeling time period. This information will help quantify the uncertainty of the meteorological model inputs into the dispersion model, which will aid in understanding the propagated uncertainty in the dispersion modeling outputs. Next, an evaluation of the emission rates generated by both the Industrial Source Complex (Gaussian) model and the WindTrax (backward-Lagrangian stochastic) model revealed that the calculated emission concentrations from each model using the average emission rate generated by the model are extremely close in value. However, the average emission rates calculated by the models vary by a factor of 10. This is extremely troubling. In conclusion, current and future sources are regulated based on emission rate data from previous time periods. Emission factors are published for regulation of various sources, and these emission factors are derived based upon back-calculated model emission rates and site management practices. Thus, this factor of 10 ratio in the emission rates could prove troubling in terms of regulation if the model that the emission rate is back-calculated from is not used as the model to predict a future downwind pollutant concentration.

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