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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.
51

None

Yeh, Ching-te 29 July 2008 (has links)
In Taiwan, most of the energy relies on imports due to few natural resources. Further more, scientists estimate that crude oil will be depleted within 40 years. A high cost energy era has arrived. Skyrocketing oil prices have a severe negative impact on the cost structure of the Taiwan Power Company (TPC), which has an estimated deficit of NT$70 billion in 2007. TPC has faced a difficult dilemma: whether to raise the electricity rate or become bankrupt. Eventually, the government has to intervene. The Kyoto Protocol was in effect in February 2005. It is expected that the environmental convention of reducing of CO2 will become an international movement following ISO14000. With every one kilowatt hour of electricity is generated by TPC, 638g of CO2 were produced. The products of made-in-Taiwan will not received international approval and will be boycotted by the International market if the energy efficiency of national enterprise is too low. Air compressor system, which is as important as water and electricity, is popularly used in almost all industries. However, its high energy-consumption and low efficiency system is seldom noticed. The energy cost of air compressor system is about 80% of the total operational cost which includes the electricity costs of all the machinery and lightings. How to improve air compressor efficiency plays an important role in the manufacture¡¦s production cost and its competition against other industries. Facing fierce competition and low profit, the industries must not only continuously innovate and reduce the cost to enhance competition ability for keeping market share, but also increase energy efficiency and reduce the emission of greenhouse gases by the green production method meeting the environmental requirement. The report is the summary of the interviews with many industry leaders who are involved in the air compressor production or the government officials who are in charge of energy-saving promotion. It also combines with the data of actual measurement of the compressor systems to research if the investment willingness of manufacturers is reflected by their operation cost, operation strategy, the risky consideration when facing law and the information getting of compressor energy-saving. The results of the study are: Clarify the main factors which influence the investment willingness to compressor energy-saving. (A) The cost side: The investment willingness is influenced by the cognition of the leaders of manufacturer unit or business owner to compressor system cost. (B) The strategy side: The investment willingness is influenced by the cognition of the leaders of manufacturer unit or business owner to the operation strategy on compressor system. (C) The legal side: The investment willingness is influenced by the cognition of the leaders of manufacturer unit or business owner to the legal affection to business. (D) The information side: The investment willingness is influenced by getting the information of energy-saving of compressor system. Finally, the study proposes a feasible project to the industries and the government officials who promote energy saving.
52

An apparatus to investigate photon induced gaseous reactions using Fourier transform infrared spectroscopy

Manning, Gregory A. January 2000 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 2000. / Typescript. Vita. Includes bibliographical references (leaves 132-137). Also available on the Internet.
53

Ekonominiai klimato kaitos švelninimo instrumentai ir jų vertinimas Lietuvoje / Economical instruments of reducing climate change and their evaluating in Lithuania

Junevičiūtė, Eglė 24 January 2012 (has links)
Klimato kaita ir jos švelninimo instrumentų įgyvendinimas yra prioritetinis visų pasaulio šalių tikslas. Šiuo metu yra taikoma daug įvairių klimato kaitos švelninimo instrumentų, skirtų atsinaujinančių energijos išteklių ir energijos efektyvumo didinimui, energijos tiekimo patikimumui ir kt., kuriuos plačiai nagrinėja daugelis pasaulio mokslininkų. Magistro baigiamojo darbo tikslas buvo apžvelgti Lietuvoje šiuo metu taikomus ekonominius klimato kaitos švelninimo instrumentus bei juos kokybiškai ir kiekybiškai įvertinti. Iškeltam tikslui pasiekti suformuluoti uždaviniai: apžvelgti moksline literatūroje nagrinėjamus pagrindinius klimato kaitos švelninimo instrumentų taikymo teorinius aspektus; išnagrinėti pagrindinius klimato kaitos švelninimo instrumentus, taikomus Lietuvoje; įvertinti klimato kaitos ekonominius instrumentus įtakojančiais šiltnamio efektą sukeliančių dujos sumažėjimą bei atsinaujinančiųjų energijos išteklių plėtrą Lietuvoje; sudarytu vertinimo modeliu atlikti klimato kaitos švelninimo instrumentų ekonominį vertinimą; remiantis atliktu vertinimu, pateikti išvadas. Darbo struktūrą nulėmė užsibrėžti darbo tikslai bei numatyti uždaviniai, kurių sprendimas pateikiamas trijose darbo dalyse. Pirmoje dalyje apžvelgti moklinėje literatūroje nagrinėjami pagrindiniai klimato kaitos švelninimo instrumentų taikymo teoriniai apsektai, tokie kaip klimato indikatoriai bei būklė pasaulyje ir Lietuvoje, Lietuvos darnios plėtros prioritetiniai rodikliai ir apžvelgtos ekonominius... [toliau žr. visą tekstą] / Climate change and implementation of its reducing instruments is underlying goal of all countries. At present there are plenty of climate change instruments being applied which are used for increasing shifting energy resources and effectiveness of energy, reliability of energy supplying etc. that are widely discussed by many scientists all over the world. The goal of Master's thesis was a review of economical instruments for reducing climate change used in Lithuania and their quantitative and qualitative evaluation. To reach the goal following tasks were set: to survey the nonfiction theoretical aspects of using main instruments for reducing climate change; analyse the main instruments for reducing climate change that are used in Lithuania; evaluate the economical instruments for reducing climate change that affect the reduction of gas causing the greenhouse effect and development of shifting energy resources in Lithuania; to make the economical evaluation of instruments for reducing climate change with the help of created evaluating model; to make conclusion refering to the evaluation. Thesis consist of three parts that were determined by stated goals and tasks. In first part are analysed the nonfiction theoretical aspects of using main instruments for reducing climate change, such as climate indicators and state in Lithuania and all over the world, underlying rates of Lithuanian regular development. Also the directives introducing economical instruments of regulating... [to full text]
54

Agrohydrological sensitivity analyses with regard to projected climate change in Southern Africa.

Lowe, Kerry Lynne. January 1997 (has links)
Climate change resulting from the augmented "greenhouse effect" is likely to have significant effects on the terrestrial hydrological system and the social and ecological systems linked to it. Climate change could potentially affect inputs to the agrohydrological system such as rainfall, temperature and potential evaporation; processes within the system such as vegetation dynamics and crop production; and hydrological responses such as runoff, recharge of soil water into the vadose zone and net irrigation demand. This study outlines the use of a daily water budget model, ACRU, and SCENGEN, a climate change scenario generator, to assess potential impacts of global climate change on agricultural production and hydrological responses in southern Africa. This study also considers potential impacts of climate change on plant response which may determine the extent of potential impacts of climate change on agricultural production and hydrological response. Two approaches to climate change impact studies are adopted for use in this study. The first, and more conventional approach considers the impact of a specified climate change scenario, in this case developed with the use of SCENGEN, on the terrestrial hydrological system. The second approach considers the degree of climate change, in this case precipitation change, required to perturb the hydrological system significantly in the various climate regimes found in southern Africa. A comparative analysis of the sensitivity of selected hydrological responses to climate change produced the following results, in ascending order of sensitivity: net irrigation demand < stormflow response < runoff < recharge into the vadose zone. The impacts of a specific climate scenario change on hydrological responses produced unexpected results. A general decrease in mean annual precipitation over southern Africa is predicted for the future with SCENGEN. However, widespread simulated increases in runoff, soil moisture content in the A- and B-horizon and recharge into the vadose zone are obtained. These increases are a product of the CO2 "fertilisation" feedback, which is incorporated as a maximum transpiration suppression routine, in the ACRU model. Net irrigation demand, which is not linked to this routine, is simulated to increase in the future. / Thesis (M.Env.Dev.)-University of Natal, Pietermaritzburg, 1997.
55

National policy choices for an international problem case studies in greenhouse policy /

Kelly, Geoffrey. January 2008 (has links)
Thesis (Ph.D.)--University of Wollongong, 2008. / Typescript. Includes bibliographical references: leaf 317-346.
56

An apparatus to investigate photon induced gaseous reactions using Fourier transform infrared spectroscopy /

Manning, Gregory A. January 2000 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 2000. / Typescript. Vita. Includes bibliographical references (leaves 132-137). Also available on the Internet.
57

Avaliação de gases efeito estufa na cidade do Rio de Janeiro / Evaluation of green house gases in Rio de Janeiro city

Cleyton Martins da Silva 14 February 2012 (has links)
O presente trabalho teve como objetivo a validação de uma metodologia de amostragem para GEE Gases do Efeito Estufa, com a utilização de seringas e análise por cromatografia de fase gasosa com múltiplos detectores. O trabalho se dividiu em duas etapas. A primeira etapa consistiu em um teste de estabilidade avaliando o meio de amostragem proposto, a seringa, e comparando-o a dois meios de amostragem convencionais canister e bolsa de teflon -, utilizando uma amostra padrão de GEE. A segunda etapa foi a aplicação desta nova metodologia de amostragem na cidade do Rio de Janeiro, buscando a avaliação da concentração dos GEE em diferentes bairros da cidade e a correlação destas com dados meteorológicos e características da localização dos pontos amostrados. Nestas amostragens realizadas na cidade do Rio de Janeiro obteve-se uma média de 536 ppmv, 2,04 ppmv e 274 ppbv, para o CO2, CH4 e N2O, respectivamente, que foram os GEE analisados. Foi possível neste trabalho verificar o grau de correlação dos GEE estudados com variáveis meteorológicas, bem como com outros poluentes já legislados e participantes de monitoramento contínuo. As conclusões alcançadas foram que a nova metodologia proposta para amostragem de GEE é viável devido ao seu bom desempenho no teste de estabilidade, ao baixo custo do material empregado e à praticidade do mesmo, e que as concentrações dos GEE avaliados na cidade do Rio de Janeiro encontram-se superiores às concentrações indicadas como médias globais para os mesmos. Apontando desta forma, a necessidade de um monitoramento contínuo destes de forma a contribuir para a tomada de ações de mitigação dos GEE / The purpose of this study is to validate a sampling methodology for GHG Greenhouse Gases, with the use of syringes and analyzed by gas chromatography with multiple detectors. The work was divided into two steps. The first one consisted of a stability test evaluating the proposed use of sampling, the syringe, and comparing it to two conventional sampling media - canister and teflons bag - using a standard sample of GHG. The second step was the application of this new sampling methodology in the city of Rio de Janeiro, seeking the GHG concentrations assessment in different districts of the city and the correlation of these data and meteorological characteristics of the location of sampling sites. In these samples collected in the city of Rio de Janeiro resulted in an average of 536 ppmv, 2.04 ppmv and 274 ppbv, for CO2, CH4 and N2O, respectively, which were the GHG analyzed. It was possible, in this paper, to verify the degree of correlation into the studied GHG and the meteorological variables, as well into others pollutants that are already legislated and participates of a continuous monitoring plan. The conclusions reached were that the proposed new methodology for GHG sampling is viable due to its good performance in stability, low cost of the material used and the practicality of it, and that the concentrations of greenhouse gases measured in the city of Rio de Janeiro are higher than the global average concentrations of them. Pointing, this way, the need for continuous monitoring of these, that should contribute to the actions of GHG mitigation
58

Mudanças de uso da terra e estimativas de emissões antrópicas de CO2 em bacia hidrográfica /

Sousa, Jocy Ana Paixão de. January 2018 (has links)
Orientador: Roberto Wagner Lourenço / Resumo: As interferências antrópicas sobre natureza sempre provocaram impactos ambientais. Porém, entre os mais significativos encontram-se as mudanças de uso da terra, nos quais contribuem com as emissões dos gases do efeito estufa. Entre esses principais gases destacam-se o dióxido de carbono, CO2. O estudo apresentou como objetivo estimar as emissões do dióxido de carbono devido as mudanças de uso da terra para a análise do fluxo de carbono em bacia hidrográfica. A área de estudo localiza-se na Bacia Hidrográfica do Rio Una, Ibiúna, São Paulo. Para atingir os objetivos foram realizados o mapeamento de uso do solo e cobertura vegetal, mapeamento pedológico, análise da textura do solo, mapeamento da vegetação pretérita, estoque de carbono sob associação solo-vegetação, matriz de transição e os cálculos das emissões líquidas de CO2. Constatou-se que em relação ao mapeamento do uso do solo e cobertura vegetal, o maior quantitativo foi de floresta e estas predominam no sul da bacia. Ao longo de nove anos houve uma redução de florestas, campo e área alagada e um aumento da área de agricultura, área urbana, pastagem e reflorestamento. Foram encontrados solos do tipo Argissolos e Latossolos, além das texturas argilosa, franco-argilo-arenosa, argilo-arenosa e franco-argilosa. Para a vegetação pretérita constatou-se floresta ombrófila densa montana, floresta estacional decidual e semidecidual. Em relação ao conteúdo de carbono no solo sob a associação solo-vegetação foram definidos valores ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Anthropogenic interference with nature has always had environmental impacts. However, among the most significant are land use changes, in which they contribute to the emissions of effect gases, especially carbon dioxide, CO2. The objective of the study was to estimate carbon dioxide emissions due to the change in land use for an analysis of the carbon flux in the watershed. The study area is located in the Una Watershed, Ibiúna, São Paulo. To achieve the objectives, the mapping of land use and vegetation cover, pedological mapping, soil texture analysis, mapping of past vegetation, carbon stock under soil-vegetation association, transition matrix, and calculations of net CO2 emissions. It was verified that in relation to the mapping of the land use and vegetal cover, the biggest quantitative one was of forest and these predominate in the south of the basin. During nine years there was a reduction of forests, field and flooded area and an increase of the area of agriculture, urban área, pasture and reforestation. Soils of the type Argisols and Latosols were found, in addition to clay, clay-loam-sandy, clay-sandy and loam-loamy textures. For the past vegetation it was verified dense montane forest, deciduous and semidecidual forest. Regarding the non-singlet carbon content in a soil-vegetation association to define values ranging from 2.59 to 6.33 Kgc / m2. In the transitional matrices for the periods 2007-2010, 2010-2013 and 2013-2016, it was observed that the forest converted... (Complete abstract click electronic access below) / Mestre
59

Ensino médio e interdisciplinaridade : um estudo sobre o conceito de efeito estufa /

Tychanowicz, Silmara Denise. January 2005 (has links)
Orientador: Ana Maria de Andrade Caldeira / Banca: Maria Guiomar Carneiro Tomazello / Banca: João José Caluzi / Resumo: Conceituar fenômenos estudados em sala de aula aparentemente é um tema simples, mas afirmar que foi reconhecido ou se foram estabelecidas relações deste fenômeno com o sujeito que o vivencia, é a principal discussão que apresenta esta pesquisa. Visamos examinar as possibilidades e contribuições de uma Metodologia de Ensino como instrumento auxiliar ao planejamento e desenvolvimento do processo de compreensão de fenômenos da natureza. Para isso, serão descritos os instrumentos utilizados no desenvolvimento da metodologia sobre o tema "Efeito Estufa", que foi realizada junto a alunos/as de 1ª série do Ensino Médio. O modelo proposto procura estabelecer patamares pedagógicos concebidos a partir das tríades sucessivas que marcam a evolução do conhecimento: perceber/relacionar/conhecer, dentro de uma perspectiva interdisciplinar. A avaliação dos resultados do trabalho, a partir da análise dos materiais escritos produzidos pelos estudantes ao longo do processo, nos leva refletir a complexidade da aprendizagem humana. / Abstract: Conceptualizing phenomena in the class room is apparently a simple matter, but the assertion on whether its acknowledgement occurs and whether the relationships established between the phenomenon and the subject who experiences it takes place - this is the main discussion of this research. Here we aim to examine the possibilities and contributions of a Teaching Methodology as an auxiliary tool in planning and developing the process of understanding nature phenomena. Thus, the tools used in methodology development using the theme "Greenhouse Effect" performed with first grade students of highschool level are described. The proposed model aims to establish pedagogical paths conceived from successive trinities that benchmark knowledge evolution: perception/relationship/knowledge, from a multidisciplinary perspective. Result evaluation from the analysis of written material produced by the students throughout the process invite us to reflect about the complexity of the human learning process. / Mestre
60

Estoques de carbono em solos dos tabuleiros costeiros paraibanos: diferenças entre ambientes. / Carbon stock in soils of the tabuleiros costeiros paraibanos: differences between environments.

BARROS, José Deomar de Souza. 03 October 2018 (has links)
Submitted by Maria Medeiros (maria.dilva1@ufcg.edu.br) on 2018-10-03T11:11:54Z No. of bitstreams: 1 JOSÉ DEOMAR DE SOUSA BARROS - DISSERTAÇÃO (PPGRN) 2011.pdf: 2202716 bytes, checksum: 51722b0957373fb01ec413977992f302 (MD5) / Made available in DSpace on 2018-10-03T11:11:54Z (GMT). No. of bitstreams: 1 JOSÉ DEOMAR DE SOUSA BARROS - DISSERTAÇÃO (PPGRN) 2011.pdf: 2202716 bytes, checksum: 51722b0957373fb01ec413977992f302 (MD5) Previous issue date: 2011-02-11 / Capes / A substituição de ambientes de mata por cana-de-açúcar leva a importantes mudanças no estoque de carbono e de nitrogênio do solo e, conseqüentemente, na ciclagem global desses elementos. O estudo foi realizado em área situada no município de Capim, Estado da Paraíba, teve por objetivo quantificar os efeitos de diferentes ambientes sobre os estoques de carbono (C) e nitrogênio (N) nos Tabuleiros Costeiros paraibanos. Os solos estudados foram Argissolo Acinzentado distrófico e Neossolo Quartzarênico. As amostragens de solo foram efetuadas em cinco repetições, nas profundidades de 0-5, 5-10, 10-20 e 20-40 cm. Os ambientes selecionados foram, a saber: mata natural; cana-de-açúcar com vinhaça e cana-de-açúcar sem vinhaça. Os valores de pH, bases trocáveis e P, foram variáveis, refletindo o efeito de cada ambiente. Os teores e estoques de carbono e nitrogênio diminuíram após a mudança de mata nativa para o plantio de cana-de-açúcar. Em geral, não houve diferença significativa para os teores e estoques de carbono do solo entre os ambientes de cana-de-açúcar nas diferentes profundidades de solo avaliadas. Mas, houve diferença significativa nos teores e no estoque de carbono e de nitrogênio do sistema de cultivo da cana sem aplicação da vinhaça em relação à mata nativa. Os resultados deste estudo mostram que o tratamento com aplicação da vinhaça promoveu melhorias nos atributos químicos do solo como o aumento do pH e da disponibilidade de K e P nas camadas superficiais do solo. Este manejo proporcionou o aumento aparente no estoque de carbono e nitrogênio. Diante disso, o manejo do solo com aplicação de vinhaça pode tornar-se uma alternativa para mitigar as emissões dos gases de efeito estufa, contribuindo para a sustentabilidade do sistema de produção canavieira. / The replacement of rain forest for sugar cane leads to significant changes in carbon stock and soil nitrogen and, consequently, the global cycling of these elements. The study was conducted in an area located in the municipality of Capim, Paraíba State, quantify the effects of different environments on the stocks of carbon (C) and nitrogen (N) in the Tabuleiros Costeiros Paraibanos. The soils were Argissolo Acinzentado distrófico típico e Neossolo Quartzarênico. The soil samples were performed in five replicates, at 0-5, 5-10, 10-20 and 20-40 cm. The environments were selected, namely: natural forest, sugar cane vinasse and cane sugar without vinasse. The pH, exchangeable bases and P, were variable, reflecting reflecting the effect of each environment. The concentrations and pools of carbon and nitrogen decreased after the change of native forest to plant sugar cane. In general, no significant difference in the levels and stocks of soil carbon between the environments of cane sugar in the different soil depths evaluated. But there were differences in the amounts and stock of carbon and nitrogen in cropping system without cane vinasse application in relation to native forest. The results of this study show that treatment with vinasse application promotes improvements in soil chemical properties such as pH increases and the availability of K and P in the surface layers of soil. This gave management the apparent increase in carbon storage and nitrogen. Thus, the management of soil with vinasse application can become an alternative to mitigate emissions of greenhouse effect, contributing to the sustainability of sugar cane production.

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