894 resultados para CO2 emissions


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This thesis consists of a summary and four self-contained papers. Paper [I] Following the 1987 report by The World Commission on Environment and Development, the genuine saving has come to play a key role in the context of sustainable development, and the World Bank regularly publishes numbers for genuine saving on a national basis. However, these numbers are typically calculated as if the tax system is non-distortionary. This paper presents an analogue to genuine saving in a second best economy, where the government raises revenue by means of distortionary taxation. We show how the social cost of public debt, which depends on the marginal excess burden, ought to be reflected in the genuine saving. We also illustrate by presenting calculations for Greece, Japan, Portugal, U.K., U.S. and OECD average, showing that the numbers published by the World Bank are likely to be biased and may even give incorrect information as to whether the economy is locally sustainable. Paper [II] This paper examines the relationships among per capita CO2 emissions, per capita GDP and international trade based on panel data spanning the period 1960-2008 for 150 countries. A distinction is also made between OECD and Non-OECD countries to capture the differences of this relationship between developed and developing economies. We apply panel unit root and cointegration tests, and estimate a panel error correction model. The results from the error correction model suggest that there are long-term relationships between the variables for the whole sample and for Non-OECD countries. Finally, Granger causality tests show that there is bi-directional short-term causality between per capita GDP and international trade for the whole sample and between per capita GDP and CO2 emissions for OECD countries. Paper [III] Fundamental questions in economics are why some regions are richer than others, why their growth rates differ, whether their growth rates tend to converge, and what key factors contribute to explain economic growth. This paper deals with the average income growth, net migration, and changes in unemployment rates at the municipal level in Sweden. The aim is to explore in depth the effects of possible underlying determinants with a particular focus on local policy variables. The analysis is based on a three-equation model. Our results show, among other things, that increases in the local public expenditure and income taxe rate have negative effects on subsequent income income growth. In addition, the results show conditional convergence, i.e. that the average income among the municipal residents tends to grow more rapidly in relatively poor local jurisdictions than in initially “richer” jurisdictions, conditional on the other explanatory variables. Paper [IV] This paper explores the relationship between income growth and income inequality using data at the municipal level in Sweden for the period 1992-2007. We estimate a fixed effects panel data growth model, where the within-municipality income inequality is one of the explanatory variables. Different inequality measures (Gini coefficient, top income shares, and measures of inequality in the lower and upper part of the income distribution) are examined. We find a positive and significant relationship between income growth and income inequality measured as the Gini coefficient and top income shares, respectively. In addition, while inequality in the upper part of the income distribution is positively associated with the income growth rate, inequality in the lower part of the income distribution seems to be negatively related to the income growth. Our findings also suggest that increased income inequality enhances growth more in municipalities with a high level of average income than in municipalities with a low level of average income.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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With the increase in cement consumption, it has quickly become one of the inputs most consumed by mankind over the last century. This has caused an increase in CO2 emissions, as cement production releases large quantities of this gas into the atmosphere. Adding this fact to the growing consciousness of environmental preservation, it has led to a search for alternatives to cement to complement its derivatives, in the form of waste materials like the ashes. This research aimed to analyze the properties of mortars in fresh and hardened state with partial replacement of Portland cement by residual algaroba wood ash (CRLA) potteries produced by the state of Rio Grande do Norte. The CRLA was collected and sieved, where part of it was ground and characterized in comparison with that just sifted, being characterized according to its chemical composition, grain size, fineness, density, bulk density and index of pozzolanic activity. It was found that the wood ash does not act as pozzolan, and grinding it has not changed its characteristics compared to those just sifted, not justifying its use. Two traces were adopted for this research: 1:3 (cement: fine sand) and 1:2:8 (cement: hydrated lime: medium sand); both in volume, using as materials the CRLA just sifted, CP II F-32 Portland cement, CH-I hydrated lime, river sand and water from the local utility. For each trace were adopted six percentages of partial replacement of cement for wood ash: 0% (control) 5%, 7%, 10%, 12% and 15%. In the fresh state, the mortars were tested towards their consistency index and mass density. In the hardened state, they were tested towards their tensile strength in bending, compressive strength and tensile adhesion strength, and its mass density in the hardened state. The mortar was also analyzed by scanning electron microscopy and X-ray diffraction. Furthermore, it was classified according to NBR 13281 (2005). The results showed that up to a content of 5% substitution and for both traces, the residual algaroba wood ash can replace Portland cement without compromising the mortars microstructure and its fresh and hardened state

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The need to build durable structures and resistant to harsh environments enabled the development of high strength concrete, these activities generate a high cement consumption, which implies factor in CO2 emissions. Often the desired strength is not achieved using only the cement composition. This study aims to evaluate the influence of pozzolans with the addition of metakaolin on the physical mechanics of high strength concrete comparing them with the standard formulation. Assays were performed to characterize the aggregates according to NBR 7211, evaluation of cement and coarse aggregate through the trials of petrography (NBR 15577-3/08) and alkali-aggregate reaction (NBR 15577-05/08). Specimens were fabricated according to NBR 5738-1/04 with additions of 0%, 4%, 6%, 8% and 10% of metakaolin for cement mortars CP V in the formulations. For evaluation of the concrete hardened in fresh state and scattering assays were performed and compressive strength in accordance with the NBR 7223/1992 and NBR 5739-8/94 respectively. The results of the characterization of aggregates showed good characteristics regarding size analysis and petrography, as well as potentially innocuous as the alkali-aggregate reaction. As to the test of resistance to compression, all the formulations with the addition of metakaolin showed higher value at 28 days of disruption compared with the standard formulation. These results present an alternative to reduce CO2 emissions, and improvements in the quality and durability of concrete, because the fine particle size of metakaolin provides an optimal compression of the mass directly influencing the strength and rheology of the dough

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Muitos mecanismos provocados pela ação humana vêm gerando um aumento na queima de combustíveis fósseis e processos químicos (produtos orgânicos, carvão, madeira, óleo diesel, gasolina e outros derivados de petróleo) e, consequentemente, há um aumento na emissão de CO2 na atmosfera. Uma das alternativas para a captura desse poluente é o processo de adsorção, o qual pode ajudar na redução do CO2. As hidrotalcitas ou hidróxidos duplos lamelares (HDL s) estão dentre esses materiais estudados, já que apresentam alta estabilidade e uma boa porosidade, tornando-se assim um promissor adsorvente de gases poluentes. Os HDL s formam um grupo de argilas do tipo aniônico que consiste em camadas positivamente carregadas de óxido de metal (ou hidróxido de metal) com intercamadas de ânions. Foi constatado que ânions que possuem duas cargas negativas, estabilizam muito mais que ânions monovalentes, sendo o carbonato o mais estável dos ânions divalentes. Neste trabalho, foi proposta uma modificação na síntese direta através da co-precipitação a pH constante utilizando sais de cátions divalentes (Mg2+) e trivalentes (Al3+) reportados na literatura. Durante a síntese dos HDL s retirou-se o carbonato, bem como, utilizou-se um copolímero como um template para o alargamento das lamelas. As amostras foram caracterizadas utilizando as técnicas de DRX, TG/DTG, FTIR, MEV/EDX, MET e adsorção e dessorção de N2. Os dados obtidos indicam que a estrutura, mesmo após a modificação, apresentou resultados condizentes com os encontrados na literatura. Dentre as várias aplicações dos HDL s foi realizado o estudo da adsorção do CO2. A capacidade de adsorção do material foi testada de acordo com o tempo de contato entre o adsorvente e o adsorbato, sendo esperado que os materiais tratados com template apresentassem um maior desempenho

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In this work the relationship between CO2 emissions and the soil properties of a tropical Brazilian bare soil was investigated. Carbon dioxide emissions were measured on three different days at different soil temperature and the soil moisture conditions, and the soil properties were investigated at the same points that emissions were measured. The soil CO2 emissions were correlated to carbon content, cation exchange capacity and free iron content at the 65 points studied in an area of 100 x 100 m located in southern Brazil. (C) 2000 Elsevier B.V. Ltd. All rights reserved.

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Reuse of industrial and agricultural wastes as supplementary cementitious materials (SCMs) in concrete and mortar productions contribute to sustainable development. In this context, fluid catalytic cracking catalyst residue (spent FCC), a byproduct from the petroleum industry and petrol refineries, have been studied as SCM in blended Portland cement in the last years. Nevertheless, another environmental friendly alternative has been conducted in order to produce alternative binders with low CO2 emissions. The use of aluminosilicate materials in the production of alkali-activated materials (AAMs) is an ongoing research topic which can present low CO2 emissions associated. Hence, this paper studies some variables that can influence the production of AAM based on spent FCC. Specifically, the influence of SiO 2/Na2O molar ratio and the H2O/spent FCC mass ratio on the mechanical strength and microstructure are assessed. Some instrumental techniques, such as SEM, XRD, pH and electrical conductivity measurements, and MIP are performed in order to assess the microstructure of formed alkali-activated binder. Alkali activated mortars with compressive strength up to 80 MPa can be formed after curing for 3 days at 65°C. The research demonstrates the potential of spent FCC to produce alkali-activated cements and the importance of SiO2/Na2O molar ratio and the H2O/spent FCC mass ratio in optimising properties and microstructure. © 2013 Elsevier Ltd. All rights reserved.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Pós-graduação em Zootecnia - FCAV

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Pós-graduação em Agronomia (Produção Vegetal) - FCAV

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The energy sector is a dominant one in Trinidad and Tobago and it plays an important role in the twin-island republic‟s economy. In 2008, the share of the energy sector in gross domestic product (GDP) amounted to approximately 48% while contributing 57% to total Government revenue. In that same year, the sector‟s share of merchandise exports was 88%, made up mainly of refined oil products including petroleum, liquefied natural gas (LNG), and natural gas liquids (Central Bank of Trinidad and Tobago, 2009). Trinidad and Tobago is the main exporter of oil in the Caribbean region and the main producer of liquefied natural gas in Latin America and the Caribbean. The role of the country‟s energy sector is, therefore, not limited to serving as the engine of growth for the national economy but also includes providing energy security for the small island developing States of the Caribbean. However, with its hydrocarbon-based economy, Trinidad and Tobago is ranked seventh in the world in terms of carbon dioxide (CO2) emissions per capita, producing an estimated 40 million tonnes of CO2 annually. Almost 90% of these CO2 emissions are attributed directly to the energy sector through petrochemical production (56%), power generation (30%) and flaring (3%). Trinidad and Tobago is a ratified signatory to the United Nations Framework Convention on Climate Change and the Kyoto Protocol. Although, as a non-Annex 1 country, Trinidad and Tobago is not required to cut its greenhouse gas emissions under the Protocol, it is currently finalizing a climate change policy document as well as a national energy policy with specific strategies to address climate change. The present study complements the climate change policy document by providing an economic analysis of the impact that climate change could have on the energy sector in Trinidad and Tobago under the Intergovernmental Panel on Climate Change alternative climate scenarios (A2 and B2) as compared to a baseline situation of no climate change. Results of analyses indicate that, in the short-run, climate change, represented by change in temperature, is not a significant determinant of domestic consumption of energy, electricity in particular, in Trinidad and Tobago. With energy prices subsidized domestically and fixed for years at a time, energy price does not play a role in determining electricity demand. Economic growth, as indicated by Gross Domestic Product (GDP), is the single major determinant of electricity consumption in the short-run. In the long-run, temperature, GDP, and patterns of electricity use, jointly determine electricity consumption. Variations in average annual temperature due to climate change for the A2 scenario are expected to lead to an increase in electricity consumption per capita, equivalent to an annual increase of 1.07% over the 2011 baseline value of electricity consumption per capita. Under the B2 scenario, the average annual increase in electricity consumption per capita over the 2011 baseline value is expected to be 1.01%. The estimated economic impact of climate change on electricity consumption for the period 2011-2050 is valued at US$ 142.88 million under the A2 scenario and US$ 134.83million under the B2 scenario. These economic impact estimates are equivalent to a loss of 0.737% of 2009 GDP under the A2 climate scenario and a loss of 0.695% of 2009 GDP under the B2 scenario. On the energy supply side, sea level rise and storm surges present significant risks to oil installations and infrastructure at the Petroleum Company of Trinidad and Tobago (PETROTRIN) Pointe-a-Pierre facilities (Singh and El Fouladi, 2006). However, data limitations do not permit the conduct of an economic analysis of the impact of projected sea level rise on oil and gas production.