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Frost, Robin. "Quantifying greenhouse gases in business supply chains". Thesis, Lancaster University, 2017. http://eprints.lancs.ac.uk/87614/.
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This thesis is written in the context of a world that is on the brink of experiencing severe climate change, and as a result must explore a variety of methods for reducing greenhouse gas (GHG) emissions. Whilst national governments and international organisations enact treaties and frameworks, the role of business as a driver of increasing GHG emissions is also being examined. In these circumstances the measurement of organisational footprints is of considerable interest. (Berners-Lee, et al., 2011) showed how the supply chain footprint of a small leisure business could be estimated using Environmentally Extended Input-Output (EEIO) modelling. The research presented in this thesis describes the updating of this model to use the most up to date ONS data. This model was used over several years with a UK based international telecommunications company. The implementation of the model, and several extensions to the methodology are presented along with summary results of the analysis. The case study demonstrates the suitability and flexibility of EEIO models for reporting supply chain footprints in organisations. A critique of the technique and further developments of the model are described.
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Jachym, Anne-Laure. "Economic Growth, Greenhouse Gases and Environmental Regulation". Master's thesis, Université Laval, 2020. http://hdl.handle.net/20.500.11794/38154.
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Dans cette étude, nous cherchons à mesurer l’impact des émissions anthropogéniques de gaz à effet de serre sur la croissance économique dans un modèle de convergence conditionnelle. Nous nous intéressons au dioxyde de carbone, au méthane, au protoxyde d’azote et au groupe des "gaz F", ainsi qu’à l’effet de la somme de ces polluants, c’est-à-dire la quasi totalité des gaz à effet de serre. Notre échantillon est composé de 81 pays, avec une variété de niveaux de revenu par habitant, entre 1993 et 2012. Nous définissons deux sous-périodes de 10 ans et nous régressons la croissance économique sur la croissance des émissions de chaque polluant séparément, sur le PIB de la première année de la période et sur plusieurs variables de contrôle. Face au risque de biais de causalité inversée entre les émissions de pollution et la croissance économique, et entre l’investissement et la croissance économique, nous décidons d’utiliser les données passées comme variables instrumentales. Plus précisément, les données de la première année de la période sont utilisées comme instruments pour la pollution et l’investissement. Mis à part le CO2, nous trouvons qu’aucun des gaz à effet de serre n’a d’impact significatif sur la croissance économique. La croissance des émissions de CO2 semble avoir un impact positif sur la croissance économique. Cet impact apparaît moins fort sur la seconde période (2003-2012) que sur la première (1993-2002). De plus, il semble plus fort pour la moitié la plus riche des pays de notre échantillon.In this study, we investigate the effect of anthropogenic greenhouse gas emissions on economic growth in a conditional convergence framework. We look at carbon dioxide, methane, nitrous oxide and the group of "F gases", as well as the effect of the sum of these pollutants, i.e. almost all greenhouse gases. Our sample is composed of 81 countries with a variety of per capita income levels and covers the period between 1993 and 2012. We define two ten-year periods and regress economic growth on emissions growth of each pollutant separately, on the first-year GDP of the period and on several control variables. To address the issue of inverse causality bias between pollution emissions and economic growth, as between investment and economic growth, we use an instrumental variable methodology. We use past data to instrument pollution and investment. More precisely, the data of the first year of the period are used as instruments. We find that, except for CO2, greenhouse gas emissions growth does not generate economic growth. CO2 emissions growth has a positive impact on economic growth. Interestingly, this impact is less pronounced between 2003 and 2012, as compared to the 1993-2002 period. In addition, the impact of CO2 emissions growth is stronger in the richer half of countries in our sample.
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Boereboom, Thierry. "Greenhouse gases investigations in ice from periglacial environments". Doctoral thesis, Universite Libre de Bruxelles, 2012. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/209673.
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L’environnement périglaciaire en général et les régions de permafrost en particulier, connus pour être très sensibles au changement climatique actuel, sont le sujet de beaucoup d’études sur les émissions de gaz à effet de serre. En effet, le dégel de ces milieux engendre la mobilisation d’une quantité importante de matière organique, précédemment piégée par le froid, favorisant les émissions de dioxyde de carbone et/ou de méthane. L’objectif premier, du présent travail, est de contribuer à l’étude des gaz enfermés dans certains types de glace de ces régions afin de mieux quantifier leur impact potentiel sur le climat.Dans un premier temps, une analyse multiparamétrique a été menée sur deux coins de glace du nord de la Sibérie dans la cadre d’une collaboration avec l’Alfred Wegener Institut (Allemagne). Cette première approche a révélé que l’analyse conjointe de la cristallographie, de l’orientation des axes optiques, du contenu en gaz total et de la composition en gaz des coins de glace est un outil puissant, complémentaire aux analyses des isotopes stables, pour comprendre les conditions paléo-climatiques qui ont régi la construction des coins de glace. Cette étude soutient également l’hypothèse de variations spatiales importantes de l’origine des masses d’air durant les variations climatiques du Pléistocène.
Dans un deuxième temps, une analyse des caractéristiques de la glace annuelle de 4 lacs du nord de la Suède a été réalisée afin d’étudier le rôle de la couverture de glace sur les émissions de gaz à effet de serre. En effet, les lacs de ces régions contribuent fortement aux émissions de méthane durant la période d’eau libre et très peu d’études ont analysé la quantité de méthane emprisonnée dans la glace hivernale et relâchée au printemps. Ce projet nous a amené à établir une nouvelle classification des bulles dans la glace de lac basée sur leur contenu en méthane, leur origine, leur forme et leur densité. Il nous a également permis de montrer que plusieurs facteurs interviennent sur le contenu en gaz dans la couverture de glace :le système hydrologique, la variation de la pression atmosphérique, la variabilité des émissions et potentiellement la proximité des sédiments sont autant de facteurs qui déterminent le contenu en gaz. L’analyse de la composition des gaz a révélé que la composition observée dans la glace est sensiblement différente de celle observée durant les périodes d’eau libre. Nous avons également, pour la première fois, établit un budget des émissions de méthane relâchées par la fonte de la couverture de glace au niveau mondial.
Cette étude a été complétée par l’analyse des isotopes 13C des gaz des différents types de bulles de notre classification en collaboration avec l’Université d’Utrecht. Nous avons alors mis en évidence que la couverture de glace influence l’équilibre biogéochimique dans l’eau en favorisant l’oxydation du méthane en dioxyde de carbone.
Doctorat en Sciences
info:eu-repo/semantics/nonPublished
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Leung, Wing Chi. "Modelling greenhouse gases in a general equilibrium model". Thesis, Massachusetts Institute of Technology, 1996. http://hdl.handle.net/1721.1/43724.
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Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1997.Includes bibliographical references (leaves 51-52).
by Wing Chi Leung.
M.Eng.
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Anselmo, Christophe. "Atmospheric greenhouse gases detection by optical similitude absorption spectroscopy". Thesis, Lyon, 2016. http://www.theses.fr/2016LYSE1131/document.
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Cette thèse porte sur le développement théorique et expérimental d’une nouvelle méthodologie de détection des gaz à effet de serre basée sur la spectroscopie optique d’absorption. La question posée était : est-il possible d’évaluer de manière univoque la concentration d’un gaz à partir d’une mesure par spectroscopie d’absorption différentielle, dans laquelle l’étendue spectrale de la source lumineuse est plus large que celle d’une ou de plusieurs raies d'absorption de la molécule considérée et que, de plus la détection n’est pas résolue spectralement ? La réponse à cette question permettra d’entrevoir à terme le développer d’un instrument de télédétection de terrain robuste sans contrainte opto-mécanique majeure aussi bien sur la source laser que sur la chaîne de détection.Ces travaux ont donné lieu au développement d’une nouvelle méthodologie que l’on dénomme « Optical Similitude Absorption Spectroscopy » (OSAS) ou spectroscopie d’absorption optique de similitude. Cette méthodologie permet donc de déterminer de manière quantitative une concentration d’un gaz à partir de mesures d’absorption différentielle non résolue spectralement sans procédure de calibration en concentration. Ceci demande alors une connaissance précise de la densité spectrale de la source lumineuse et du système de détection. Ces travaux publiés ont permis de démontrer que cette nouvelle méthodologie est dans le domaine spectral du proche infrarouge peu sensible aux conditions thermodynamiques du gaz observé. D’autre part, ces travaux ont permis de mettre en exergue l’inversion de la Loi de Beer-Lambert non résolue spectralement ce qui donne lieu à la résolution d’un système analytique non linéaire. À cette fin le développement d’un nouvel algorithme d’inversion de ce type de mesures a pu être vérifié expérimentalement en laboratoire sur le méthane, en exploitant aussi bien des sources à large bande spectrale cohérente et non cohérente. La détection de cette molécule dans l’atmosphère a pu être réalisée dans le cadre de ces travaux en couplant judicieusement la méthodologie OSAS et la technique Lidar. Ces travaux ouvrent de nombreuses perspectives sur la détection de gaz à effet de serre dans le domaine spectral infrarouge ainsi que la possibilité de détecter plusieurs molécules d’intérêt atmosphérique simultanémentThis thesis concerns the theoretical and experimental development of a new methodology for greenhouse gases detection based on the optical absorption. The problem relies on the unambiguous retrieval of a gas concentration from differential absorption measurements, in which the spectral width of the light source is wider than one or several absorption lines of the considered target gas given that the detection is not spectrally resolved. This problem could lead to the development of a robust remote sensing instrument dedicated to greenhouse gas observation, without strong technology limitations on the laser source as well as on the detection system. Solving this problem, we could propose a new methodology named: "Optical Similitude Absorption Spectroscopy" (OSAS).This methodology thus allows to determine a quantitative target gas concentration from non-resolved differential absorption measurements avoiding the use of a gas concentration calibration procedure. Thereby, a precise knowledge of the emitted power spectral density of the light source and the efficiency of the detection system are needed.This work that has been recently published could demonstrate that this new methodology applied on the NIR remains accurate even in the presence of strong atmospheric pressure and temperature gradients. Moreover, we show that inverting spectrally integrated measurements which follow the Beer-Lambert law leads to solve a nonlinear system. For this, a new inversion algorithm has been developed. It was experimentally verified in laboratory on methane by using coherent and non-coherent broadband light sources. The detection of methane in the atmosphere could be also realized by coupling the OSAS methodology and the Lidar technique. Outlooks are proposed and especially on the detection of greenhouse gases in the infrared spectral domain as well as the ability to simultaneously detect several atmospheric molecules of interest
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Prabhu, Anil K. "Catalytic Transformation of Greenhouse Gases in a Membrane Reactor". Diss., Virginia Tech, 2003. http://hdl.handle.net/10919/26430.
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Supported Ni and Rh catalysts were developed for the reforming of two greenhouse gases, methane and carbon dioxide to syngas (a mixture of hydrogen and carbon monoxide). This is an endothermic, equilibrium limited reaction. To overcome the thermodynamic limitations, a commercially available porous membrane (Vycor glass) was used in a combined reactor-separator configuration. This was to selectively remove one or more of the products from the reaction chamber, and consequently shift the equilibrium to the right. However, the separation mechanism in this membrane involved Knudsen diffusion, which provided only partial separations. Consequently, there was some transport of reactants across the membrane and this led to only marginal improvements in performance. To overcome this limitation, a new membrane was developed by modifying the Vycor substrate by the chemical vapor deposition of a silica precursor. This new membrane, termed Nanosil, provided high selectivity to hydrogen at permeabilities comparable to the support material. Application of this membrane in the combined reactor-separator unit provided higher conversions than that obtained using the Vycor membrane.Ph. D.
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O'Shea, Sebastian James. "Airborne observations and regional flux estimates of greenhouse gases". Thesis, University of Manchester, 2014. https://www.research.manchester.ac.uk/portal/en/theses/airborne-observations-and-regional-flux-estimates-of-greenhouse-gases(9cc17627-8320-4ffd-9cf7-faf4688bf20d).html.
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Methane is the second most important long-lived greenhouse gas. However, it is typically emitted to the atmosphere by spatially and temporally heterogeneous sources, meaning that local measurements cannot easily be extrapolated to represent global scales. As a consequence, its global sources and sinks are generally poorly quantified. This thesis focuses on the use of airborne observations to improve flux estimates of methane at regional scales. A commercially available cavity-enhanced absorption spectrometer has been modified here for airborne measurements of methane and carbon dioxide. An algorithm employing the system's simultaneous water vapour measurement has been derived, using laboratory experiments, to determine dry air mole fractions without the need for sample drying. The system was found to be relatively independent of the aircraft's motion and its measurements were found to be accurate to within 1.28 ppb (1 standard deviation repeatability at 1Hz of 2.48 ppb) for methane and 0.17 ppm (1 standard deviation repeatability at 1Hz of 0.66 ppm) for carbon dioxide. This new measurement capability has been deployed during three international field campaigns, data from which is used in this thesis. The composition of boreal biomass burning was measured in eastern Canada. Methane emission factors showed a high degree of variability (range 1.8 $\pm$\ 0.2 to 8.5 $\pm$\ 0.9 g (kg dry matter)$^{-1}$), accentuating the challenges with using a purely bottom-up approach to determine total methane emissions and that top-down constraints are needed. Two case studies have shown that an aircraft mass balance approach can be a valuable tool for deriving regional scale top-down flux estimates, when a suitable sampling strategy can be employed under appropriate atmospheric conditions. First, this technique was applied to the European Arctic wetlands; and second, its suitability to derive emissions from a megacity was investigated using London, UK as a test case. On both occasions, the derived fluxes were found to be in good agreement with coincident surface observations within the aircraft's sampling domain. In the case of the Arctic wetlands the excellent agreement with seasonally averaged surface observations allowed this information to be used for the evaluation of land surface models. Two commonly used models, the Joint UK Land Environment Simulator and Hybrid8 were found to underestimate the methane emission flux for this region by an order of magnitude, highlighting the large uncertainties present in future methane emission scenarios at regional scales under a changing climate.
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Hill, Heather. "Local government and greenhouse action in South Australia /". Title page, table of contents and abstract only, 1998. http://web4.library.adelaide.edu.au/theses/09ENV/09envh646.pdf.
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Figueras, Valls Marc. "Nanostructured transition metal carbides as potential catalysts for greenhouse gases conversion". Doctoral thesis, Universitat de Barcelona, 2021. http://hdl.handle.net/10803/673020.
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Over the recent decades, several studies revealed the precarious climate situation which is threatening all Life forms on earth, including mankind, even if sometimes we tend to ignore the actual fragility of our situation. Ironically, the human species is at the origin of the rapid change on climate, mostly by practicing unsustainable activities, such as the unregulated consumption of fossil fuels, excessive deforestation, extensive agriculture, and intensive livestock. All these practices have increased the concentration of greenhouse gases in the atmosphere, producing a rapid increase in the average Earth temperature with noticeable consequences in our lifetime. Nevertheless, several efforts have been conducted by the scientific community in order to revert the actual climate situation, even if society acts delayed.
One of the actual work routes implies the use of catalysts to capture and convert greenhouse gases into less harmful and more useful chemicals. This route has found in transition metal carbides (TMCs) proficient candidates that could have an important impact in the aforementioned matter. An interesting aspect of TMCs is their capacity to catalyse such transformation reactions at low temperatures and to withstand several reaction cycles without degrading. Precisely, the present Thesis unveils and discusses several reaction mechanisms involved in the greenhouse gases transformation reactions held by TMCs, particularly, focusing on MoCy nanoparticles, a largely unexplored field. This Thesis combines experimental and theoretical approaches to explain the observed experimental evidences, where custom synthetized MoC nanoparticle supported on Au(111) are able to activate methane at room temperature, hydrogenate CO2, and act as superior H2 sponges with respect to clean MoC extended surfaces. Moreover, other important findings are revealed, such as the reconstruction held by some transition metal carbides and nitrides surfaces and the intrinsic nature of clean MoC nanoparticles towards hydrogenation reactions. Overall, the present dissertation intends to encourage further efforts on developing TMC based catalyst able to be used at industrial levels.
The experimental section of this thesis has been carried out at the Brookhaven National Laboratory by the group of Prof. J. A. Rodriguez, while the computational part and results analysis has been carried out in the present institution, the Universitat de Barcelona. The results obtained have led to several joint publications.En els darreres dècades, diversos estudis han revelat la precària situació climàtica que està amenaçant totes les formes de vida a la terra, inclosa la humanitat, encara que de vegades tendim a ignorar la fragilitat de la nostra situació. Irònicament, l’espècie humana és l’origen del ràpid canvi climàtic, principalment per practicar activitats insostenibles, com el consum no regulat de combustibles fòssils, la desforestació excessiva, l’agricultura extensiva i la ramaderia intensiva. Totes aquestes pràctiques han augmentat la concentració de gasos d’efecte hivernacle a l’atmosfera, produint un ràpid augment de la temperatura mitjana de la Terra amb conseqüències notables fins i tot durant la nostra vida. No obstant això, la comunitat científica està realitzant diversos esforços per revertir la alarmant situació climàtica, fins i tot si la societat actua amb retard. Una de les rutes de treball implica l’ús de catalitzadors per capturar i convertir els gasos d’efecte hivernacle en productes químics menys nocius i més útils. Aquesta ruta ha trobat en els carburs de metalls de transició (TMC) candidats competents que podrien tenir un impacte important en la reactivitat esmentada. L’aspecte més interessant dels TMCs és la seva capacitat per catalitzar aquestes reaccions de transformació a baixes temperatures i per suportar diversos cicles de reacció sense degradar-se. Precisament, aquesta Tesi revela i analitza diversos mecanismes de reacció implicats en les reaccions de transformació dels gasos d’efecte hivernacle catalitzades pels TMC, concretament, centrant-se en les nanopartícules de MoCy, que encara romanen inexplorades. Aquesta tesi combina enfocaments experimentals i teòrics per explicar les evidències experimentals observades, on les nanopartícules de MoC sintetitzades suportades sobre Au (111) són capaces d’activar el metà a temperatura ambient, hidrogenar CO2 i actuar com a esponges H2 superiors respecte a les superfícies netes de MoC. A més, altres descobriments importants han estat revelats, com ara la reconstrucció d’algunes superfícies de TMC/TMN i la naturalesa química intrínseca de les nanopartícules de MoC netes pel que fa a les reaccions d’hidrogenació. En general, la present dissertació té la intenció de fomentar nous esforços en el desenvolupament de catalitzadors basats en TMCs que puguin ser utilitzats a nivell industrial. La secció experimental d’aquesta tesi s’ha dut a terme al Brookhaven National Laboratory pel grup del professor J. A. Rodriguez, mentre que la part computacional i l’anàlisi de resultats s’ha dut a terme a la present institució, la Universitat de Barcelona. Els resultats obtinguts han donat lloc a diverses publicacions conjuntes.
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Maltby, Johanna [Verfasser]. "Production of greenhouse gases in organic-rich sediments / Johanna Maltby". Kiel : Universitätsbibliothek Kiel, 2015. http://d-nb.info/1078504245/34.
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Totterdill, Anna Elizabeth MacKinlay. "On the mesospheric removal of very long-lived greenhouse gases". Thesis, University of Leeds, 2015. http://etheses.whiterose.ac.uk/20509/.
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The fluorinated gases SF6, NF3 and CFC-115 are chemically inert with atmospheric lifetimes of many centuries which, combined with their strong absorption of infrared radiation, results in unusually high global warming potentials. Very long lifetimes imply that potential mesospheric sinks could make important contributions to their atmospheric removal. In order to investigate this, the reactions of each species with the neutral metal atoms Na, K, Mg and Fe, which are produced by meteoric ablation in the upper mesosphere, were therefore studied. The observed non-Arrhenius temperature dependences of the reactions are interpreted using quantum chemistry calculations of the relevant potential energy surfaces. The absorption cross-section at the prominent solar Lyman-α solar emission line (121.6 nm) was also determined. In the second part of this study updated values for the infrared absorption cross sections of SF6, NF3 and CFC-115 were experimentally determined and used in two radiative transfer models in order to determine radiative forcing and efficiency values. These were carried out with thorough sensitivity analysis and included the effect of clouds and stratospheric adjustment. A three-dimensional chemistry climate model was used separately to determine updated atmospheric lifetimes of each species. Finally, we combined our results to determine updated global warming potentials over a 20, 100 and 500 year time period.
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Olesniewicz, Timothy J. "Unanticipated Consequences of Regional Greenhouse Gas Policies: Criteria Emissions and the Regional Greenhouse Gas Initiave". Fogler Library, University of Maine, 2008. http://www.library.umaine.edu/theses/pdf/OlesniewiczTJ2008.pdf.
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Morris, Samantha Anne. "Molecular ecology of methane-oxidising bacteria in drained and flooded peat". Thesis, University of Warwick, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.269192.
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Evidence has shown that changes in land-use can affect the potential of the soil to act as a methane sink. The Lakenheath site consists of drained fenland peat, which is being re-converted to wetland. At the time of this study the site consisted of four land-use types, an intensively cultivated plot, unmanaged grassland, woodland, and wetland. Peat cores were taken from the four plots and compared for their ability to act as a methane sink. CH4 uptake was measured throughout the depth profiles using gas chromatography. Clear differences in methane oxidation rates were recorded with depth and land-use. The woodland soil showed the highest capacity for atmospheric methane oxidation, and the wetland soil was only profile that had a distinct peak of methane oxidation activity (just above the water table). Despite the change in land-use, all four soils had the capacity to oxidise both high and low concentrations of methane and so acted as a methane sink. The only exception to this was the wetland soil after persistent rainfall. The uppermost layers were water saturated and all soil sections failed to oxidise methane. Methanotroph diversity in the four soils was compared using molecular biological and enrichment techniques. Total DNA was extracted from depth profiles of the four soils and PCR amplified with 16S rRNA methanotroph group-specific primers and primers specific to subunits of the pMMO and AMO (pmoA and amoA), sMMO (mmoX) and MDH (methanol dehydrogenase, mxaF). In addition, DNA was extracted from the top 5 cm of the cultivated (drained) and flooded soil and PCR amplified with primers specific to subunits of the pMMO and AMO. These PCR products were cloned and gene libraries constructed for each soil. No significant differences were observed in retrieved methanotroph sequences from these two soils, suggesting that the methanotroph population had not altered after flooding. The sequences obtained in the molecular study were predominantly amoA sequences from nitrifiers and pmoA sequences from type II methanotrophs. No type I pmoA sequences were retrieved. Type I methanotrophs, however, were isolated directly from the peat soil in the enrichment study.
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Stepp, Matthew. "Limiting transportation sector greenhouse gas emissions : the role of system interaction on policy portfolio effectiveness /". Online version of thesis, 2009. http://hdl.handle.net/1850/10633.
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Lee, Yu-tao. "A study on greenhouse gases in Hong Kong : sources and mitigation /". Hong Kong : University of Hong Kong, 1999. http://sunzi.lib.hku.hk/hkuto/record.jsp?B21301694.
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Nkongolo, Nsalambi Vakanda. "Quantification of greenhouse gas fluxes from soil in agricultural fields". Thesis, Nelson Mandela Metropolitan University, 2010. http://hdl.handle.net/10948/1474.
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Field studies were conducted at Lincoln University of Missouri (USA) and Hokkaido University (Japan) to: (i) study the relationships between greenhouse gases emissions and soil properties, (ii) assess the influence of agricultural practices on greenhouse gas fluxes and soil properties and (iii) improve the quantification of greenhouse gases from soil in agricultural fields using geospatial technologies. Results showed that besides soil temperature (T), soil thermal properties such as thermal conductivity (K), resistivity (R) and diffusivity (D) and soil pore spaces indices such as the pore tortuosity factor and the relative gas diffusion coefficient (Ds/Do) are controlling factors for greenhouse gases emissions. Soil thermal properties correlated with greenhouse gases emissions when soil temperature could not. The study has found that predicted Ds/Do and correlate with greenhouse gas fluxes even when the air-filled porosity and the total porosity from which they are predicted did not. We have also showed that Ds/Do and can be predicted quickly from routine measurements of soil water and air and existing diffusivity models found in the literature. Agricultural practices do seriously impact greenhouse gases emissions as showed by the effect of mechanized tillage operations on soil physical properties and greenhouse gas fluxes in a corn and soybean fields. In fact, our results showed that tractor compaction increased soil resistance to penetration, water, bulk density and pore tortuosity while reducing air-filled porosity, total pore space and the soil gas diffusion coefficient. Changes in soil properties resulted in increased CO2, NO and N2O emissions. Finally, our results also confirmed that greenhouse gas fluxes vary tremendously in space and time. As estimates of greenhouse gas emissions are influenced by the data processing approach, differences between the different calculation approaches leads to uncertainty. Thus, techniques for developing better estimates are needed. We have showed that Geographic Information Systems (GIS), Global Positioning System (GPS), computer mapping and geo-statistics are technologies that can be used to better understand systems containing large amounts of spatial and temporal variability. Our GIS-based approach for quantifying CO2, CH4 and N2O fluxes from soil in agricultural fields showed that estimating (extrapolating) total greenhouse gas fluxes using the “standard” approach – multiplying the average flux value by the total field area – results in biased predictions of field total greenhouse gases emissions. In contrast, the GIS-based approach we developed produces an interpolated map portraying the spatial distribution of gas fluxes across the field from point measurements and later process the interpolated map produced to determine flux zones. Furthermore, processing, classification and modeling enables the computation of field total fluxes as the sum of fluxes in different zones, therefore taking into account the spatial variability of greenhouse gas fluxes.
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Anderson, Linse N. "A greenhouse gas emissions inventory and emissions offset strategies for the University of Wyoming". Laramie, Wyo. : University of Wyoming, 2008. http://proquest.umi.com/pqdweb?did=1663116701&sid=2&Fmt=2&clientId=18949&RQT=309&VName=PQD.
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Thesis (M.A.)--University of Wyoming, 2008.Title from PDF title page (viewed on August 4, 2009). Interdisciplinary thesis in International Studies and Environment and Natural Resources. Includes bibliographical references (p. 58-63).
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Wiegard, Jean, i JWiegard@groupwise swin edu au. "Quantification of Greenhouse Gases at Visy Industries using Life Cycle Assessment". Swinburne University of Technology. School of Engineering and Science, 2001. http://adt.lib.swin.edu.au./public/adt-VSWT20030729.140753.
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Greenhouse gases (GHGs) are vital components of the earth�s atmosphere, trapping heat around the earth, maintaining temperatures necessary for human existence. Until the Industrial Revolution, these gases existed in a natural equilibrium with the environment. Since that time, anthropogenic activities such as fossil fuel burning and land clearing have increased the quantity of GHGs, such as carbon dioxide (CO2) and methane (CH4), in the earth�s atmosphere. Evidence indicates that global warming is occurring as a result of the additional accumulation of GHGs in the atmosphere.
International response to climate change resulted in the 1997 development of the Kyoto Protocol. If the Protocol is ratified, developed countries will be legally bound to reduce their GHG emissions in accordance with negotiated emission reduction targets. At the beginning of the year 2001, the Protocol was still to be ratified.
With the possibility of future GHG emission restrictions, some Australian companies have started quantifying their GHG emission levels. One such company is Visy Industries, the largest privately owned paper packaging manufacturing company in the world. Visy�s core business is the manufacture of cardboard boxes from recycled paper. As part of its future operations, a kraft pulp and paper mill is presently being built in New South Wales, Australia.
The environmental decision support tool, Life Cycle Assessment (LCA), was used to quantify Visy�s CO2 and CH4 emissions across the entire life cycle of the Visy paper recycling and virgin papermaking processes. Commercially defined LCA models were developed for both papermaking processes.
GHG emissions estimated by each model were compared and the effect of different energy sources, technologies and manufacturing processes on CO2 and CH4 emissions were assessed. The majority of emissions in the two Visy papermaking models were due to fossil fuel derived energy sources and the decomposition of wood fibre in Solid Waste Disposal Sites (SWDSs). Results were used to propose appropriate GHG reduction strategies and business opportunities.
GHG reduction strategies included increasing the use of renewable energy, reducing the volume of solid waste rejects sent to SWDS, incinerating solid waste rejects with energy recovery and sourcing steam from third party providers. Proposed GHG business opportunities included increasing the production of Greenpower from the pulp and paper mill for sale to the grid.
This thesis is an example of the practical application of current GHG knowledge and LCA methodology that was undertaken in an environment where technical, political and commercial guidelines at both a national and international level were still evolving. Nevertheless, the thesis is not a critical review of LCA methodology.
The LCA support tool was able to quantify CO2 and CH4 emissions across the life cycle of the Visy recycling and virgin papermaking processes. The chosen functional unit, the assumptions and exemptions made, and the placement of the system boundaries, were found to be critical to the Visy LCA results.
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Lee, Yu-tao, i 李裕韜。. "A study on greenhouse gases in Hong Kong: sources and mitigation". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1999. http://hub.hku.hk/bib/B31254317.
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Hall, Edith Carol Sonne. "Greenhouse gas emissions from Pacific Northwest forestry operations : implications for forest management /". Thesis, Connect to this title online; UW restricted, 2005. http://hdl.handle.net/1773/5596.
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Rata, Nigel David. "Development of new cryogenic extraction techniques for studying stable isotopic ratios in atmospheric methane". Thesis, Royal Holloway, University of London, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.312798.
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Richer, Hannah R. "Mechanistic studies of the photo-oxidation of some halogenated species of atmospheric interest". Thesis, University of East Anglia, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.238804.
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Lott, Robert Martin Terence. "Investigations into new methods for the destruction of CFâ†4 and Câ†2Fâ†6". Thesis, University of Bristol, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.389335.
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Al-Batty, Sirhan Ibrahim. "Utilization of CO2 to Mitigate Greenhouse Gas Effect". University of Toledo / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1271443724.
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Hermans, Renee Elisabeth Maria. "Impact of forest-to-bog restoration on greenhouse gas fluxes". Thesis, University of Stirling, 2018. http://hdl.handle.net/1893/27319.
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Large areas of northern peatlands have been drained and afforested in the second half of the 20th century with significant impacts on important ecosystem services, including loss of biodiversity and potential changes in C storage. A considerable effort is currently invested into restoring original peatland function and ecosystem services, with an increasing area of newly restored peatland areas over recent years. However, the effect of restoration on the greenhouse gas (GHG) budget is unknown. This study is the first quantification of CO2, CH4 and N2O fluxes from forest-to-bog restoration sites spanning 0 to 17 years in age. Further, the impact of afforestation on peat decomposition is measured in situ, and the impact of afforestation on the biochemical composition of the peat in relation to CO2 and CH4 fluxes is investigated. Results show that forest-to-bog restoration is successful from a GHG perspective, since all three major GHG fluxes of the restoration sites are changing along the chronosequence towards the fluxes from near pristine bog sites. The peat decomposition rate under the forest plantations is a big part of the total soil respiration at 126.8 ± 14.7 g C m-2 y-1 (44% of total soil CO2 efflux) and our results indicate a slowing down of peat decomposition towards the near pristine bog. CH4 fluxes increase with restoration age, whilst all sites remain a small sink for N2O. I observed changes in peat quality and nutrient availability in the pore water under forests. Different CO2 fluxes between vegetation-free peat cores from different sites for the same temperature and water level show that these differences in peat quality and nutrient availability shape the biogeochemical processes in the peatlands. However only small differences in CH4 fluxes between sites were evident, suggesting that on its own (and in absence of biotic interactions under field conditions), forestry effects on CH4 flux are limited.
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Lam, Chung, i 林松. "Greenhouse gas emissions in Hong Kong: sources, mitigations, and prospects". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2004. http://hub.hku.hk/bib/B31255887.
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Feliciano, Diana. "The contribution of rural land uses to greenhouse gas neutral regions". Thesis, University of Aberdeen, 2012. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=189641.
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Silveira, Raiza Felismino. "Energy partition and nitrogen utilization by growing goats fed encapsulated calcium nitrate /". Jaboticabal, 2017. http://hdl.handle.net/11449/151442.
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Orientador: Kleber Tomás de ResendeCoorientador: Marcia Helena Machado da Rocha Fernandes
Banca: Rafael Canonenco de Araújo
Banca: Carla Joice Härter
Resumo: O nitrato de cálcio encapsulado (NCE) tem sido estudado nos últimos anos como uma fonte de nitrogênio não proteico (NNP) e representa uma alternativa ao uso do hidrogênio livre no ambiente ruminal, reduzindo assim a emissão de metano e possibilitando uma maior eficiência no uso da energia. Assim, o objetivo do presente estudo foi avaliar o uso do nitrato de cálcio encapsulado como substituto do farelo de soja na partição de energia, oxidação do substrato e síntese de N microbiano. Para isso, doze caprinos machos castrados em crescimento, com peso inicial de 21,95 kg ± 3,19 kg foram usados em um quadrado latino 3 x 3 quadruplicado com três períodos de 48 dias, agrupados pelo peso corporal e distribuídos aleatoriamente em um dos três tratamentos ECN0(SBM) - controle baseado em farelo de soja; ECN1.25 - 1,25% de NCE na matéria seca; ECN2.5 - 2,5% de NCE na matéria seca. Cada período consistia de 21 dias de adaptação, 5 dias de ensaio de metabolismo e 15 dias de mensuração de gases. Entre os períodos foi feito um washout de 7 dias onde todos os animais recebiam a dieta controle. Os dados foram analizados usando o procedimento MIXED do SAS (versão 9.4; SAS Inst., Cary, NC, USA). O modelo usado foi Yjkm: μ + LSi + Periodj + Ani(LS)ki + Treatm + єijkm. Quando significante, o efeito de níveis de NCE foi decomposto em dois contrastes polinomiais ortogonais (linear e quadrático). A significância declarada foi de P < 0,05. As variáveis de produção de calor (PC) e produção de calor em je... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Encapsulated calcium nitrate (ECN) has been studied in last years as a source of non-protein nitrogen (NPN) and represents an alternative to use of free hydrogen in the ruminal environment, thus reducing the emission of methane and a higher efficiency in use of energy. Thus the aim of this study was to assess the impact of the use of encapsulated calcium nitrate as a substitute for soybean meal in the energy partition, substrate oxidation, and microbial N synthesis. For this, twelve castrated male growing goats, with initial average weight of 21.95 kg ± 3.19 kg were used in a quadruplicated 3 x 3 Latin square design with three 48-d periods, grouped by body weight (BW) and randomly assigned to three diets: ECN0(SBM) - control based on soybean meal; ECN1.25 - 1.25% of encapsulated calcium nitrate (ECN) on dry matter (DM) basis; ECN2.5 - 2.5% of ECN on DM basis. Each period comprised 21 days for adaptation, five days for metabolism trial (d22 to d26) and 15 days for gas measurements (d27 to d38). Between periods, a washout period was provided for 7 d during which the control diet was fed. The data were analyzed using MIXED procedure of SAS (version 9.4; SAS Inst., Cary, NC, USA). The model used for each treatment was the following: Yjkm: μ + LSi + Periodj + Ani(LS)ki + Treatm + єijkm. When significant, the effect of levels of ECN was decomposed into two orthogonal polynomial contrasts (linear and quadratic). Significance was declared at P < 0.05. The heat production (HP) and fas... (Complete abstract click electronic access below)
Mestre
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Holtwisch, Christoph. "Das Nichteinhaltungsverfahren des Kyoto-Protokolls : Enstehung - Gestalt - Wirkung /". Berlin : Duncker & Humblot, 2006. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=015046094&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.
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Chadwick, David R. "The effect of climate on decomposition in forest ecosystems". Thesis, Lancaster University, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.282376.
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Holloway, Lewis E. "Global warming and changing patterns of horticultural production in the United Kingdom". Thesis, Coventry University, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.282604.
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Dowrick, David John. "Laboratory studies of biogeochemical processes in wetlands subject to simulated climate change". Thesis, Bangor University, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.262748.
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McManus, Marcelle. "Life cycle assessment of rapeseed and mineral oil based fluid power systems". Thesis, University of Bath, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.340991.
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Greally, Brian Roger. "Development of an analytical system for the determination of highly fluorinated compounds in air samples". Thesis, University of Bristol, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.302161.
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Miller, Gemma A. "The impacts of agricultural land management on soil carbon stabilisation". Thesis, University of Edinburgh, 2016. http://hdl.handle.net/1842/25437.
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Soil is the largest terrestrial carbon (C) store, containing an estimated ~1500 Gt C in the upper 1 m of soil. The long term storage of soil organic C (SOC) requires that it is somehow protected from microbial decomposition – or ‘stabilised’ – in the soil matrix. Three mechanisms are commonly identified as factors controlling the stability of SOM: chemical recalcitrance, physical protection in aggregates and adsorption to soil mineral surfaces. The stability of SOC in the soil matrix can be influenced by management practices and changes in soil structure can lead to loss of SOC and increases in greenhouse gas (GHG) emissions. It is, therefore, important to understand the impact that management practices have on SOC stability and to manage soils in such a way as to optimise the volume of SOC which is locked away for climatically significant periods of time. Two methods are generally used to estimate SOC stability: indirectly by measuring CO2 fluxes as a proxy for SOC microbial decomposition, or directly through physical fractionation of soil in to pools with different levels of physical and chemical protection. Both methods were employed in this thesis. Arable and grassland soils which represent the range of soil textures and climatic conditions of the main agricultural areas in the UK were incubated at two different moisture contents and with or without inorganic fertiliser application and GHG fluxes from them were monitored. Soil texture, mineral N concentration and soil C concentration were found to be the most important measured variables controlling GHG fluxes of the UK agricultural soils in this study. The results were generally in support of those found in the literature for a wide range of soils, conditions and locations; however, N2O emissions from the two Scottish soils appeared to be more sensitive to inorganic N fertilisation at the higher moisture content than the other soils, with the N2O emissions being exceptionally high in comparison. Although incubations of whole soils are useful in measuring the impacts of soil management practices on GHG emissions under controlled conditions they do not identify the mechanisms controlling the stability of SOC. Dividing SOM into functional pools may identify different C stabilising mechanisms and improves soil C models. A large number of operationally defined separation methods have been used to fractionate SOM into biologically meaningful pools of different stability. Direct comparisons of different fractionation methods using radiocarbon (14C) dating and spectroscopic analyses has not previously been undertaken. Average 14C ages and chemical composition of SOM fractions isolated from a grassland soil using three published and frequently applied fractionation methods were compared. (1) a density separation technique isolating three fractions (2) a combined physical and chemical separation isolating five fractions (3) a hot-water extraction method isolating two fractions. The fractions from Method 1 had the most distinct average 14C ages, the fractions from Method 2 fell into two age groups, and both Method 3 fractions were dominated by modern C. The average 14C ages of the labile fractions from Method 1 and 2 were higher than the mineral bound fractions, although they made up a relatively small proportion of the total SOC. This was a surprising result, and spectroscopic analysis confirmed that these fractions had greater relative contents of aliphatic and aromatic characteristics than the mineral bound fractions. The presence of black C in a whole soil sample and one of the labile fractions from Method 2 was confirmed by hydrogen pyrolysis. The availability of archived soils from an abandoned long term tillage treatment experiment and the ability to relocate the plots provided a unique opportunity to assess the resilience of SOC stocks to land management practices several years after the conversion from arable to grassland. SOC stability was assessed by soil fractionation of archived (1975) and freshly collected (2014) soil samples. The mass corrected SOC stocks from the four different treatments (deep plough, shallow plough, chisel plough and direct drill) were higher in 2014 than 1975 across the whole profile (0 – 36 cm). Reductions were observed at some depths for some treatments but the overall effect was an evening out of SOC stocks across all plots. The fractionations (using Method 2), revealed that there was a relative increase in the mass of the sand and aggregate fraction but a decrease in the relative proportion of SOC stored in this fraction (physically protected). There was also a significant increase in the C:N ratio of the silt and clay fraction (chemical adsorption). This suggests that reduced disturbance of agricultural soils leads to preferential physical stabilisation of fresh SOM but also increased adsorption of older material to mineral surfaces. The labile fractions were sensitive to land-use change in all tillage treatment plots, but were more sensitive in the low impact tillage plots (chisel plough and direct drill) than the inversion tillage plots (deep plough and shallow plough). It is well established that tillage disrupts aggregation. However, a direct measurement of the level of SOM physical protection in the soil matrix due to aggregation has not previously been undertaken. The soil was fractionated using Method 1 (fractions with distinctly different 14C ages) and isolated soil fractions were incubated separately, recombined and mixed in to whole soil at three different temperatures. The C respiration rate of the isolated intra-aggregate fraction was generally consistently as high as the whole soil. This supports the theory that there is a labile component of soil which is protected from decomposition by physical protection within aggregates. Therefore, the lack of any priming effect with the addition of labile fractions to the whole soil, and indeed the suppression of emissions relative to the whole soil, was unusual. Fractions and whole soils incubated at 25 and 35 °C had a wider range of Q10 (temperature sensitivity) values than those incubated at 15 and 25 °C, however, median values were surprisingly similar (range from 0.7 to 1.9). Overall, the results from this thesis highlight the importance of the soil structure in stabilising C. Disrupting aggregates leaves a proportion of otherwise stable C susceptible to loss through microbial decomposition, particularly when the entire soil matrix is disrupted. It also provided some unexpected results which warrant future investigation; in particular, further direct measurement of physical stabilisation of SOM in soils of different type, from different climates and different land uses would be useful.
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Reinklou, Johan. "Livscykelanalys av granulärt svavel respektive torv : Vilken produkt genererar minst utsläpp av växthusgaser?" Thesis, Umeå universitet, Institutionen för ekologi, miljö och geovetenskap, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-122924.
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The purpose of this report was to investigate which of the two products peat and granular sulphur that generates the least greenhouse gas emissions. The study was performed by doing a comparative Life Cycle Assessment (LCA) on the two different products. To perform the LCA, a standard from the Swedish Standards Institute was used. Data to put into the calculation was obtained from both Umeå Energi, their contractors and different internet-sources. The data was then multiplied with specific emission factors to get the total emission of greenhouse gases, expressed as carbon dioxide equivalents. Since peat is considered both a fossil energy source and a renewable energy source two calculations were made in the case of peat production. Results showed that granular sulphur generated the least emissions (23.0), peat classified as a renewable energy source second most emissions (71.5) and peat classified as a fossil energy source by far the most emissions (978.2). The conclusion to be made by this study is that if only the emission of greenhouse gases are important when choosing a product, granular sulphur should be used. Key words: peat, greenhouse gases, LCA, sulphur.
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Lee, S. E. "Modelling interactions between climate and global vegetation in response to climate change". Thesis, University of Sheffield, 1997. http://etheses.whiterose.ac.uk/2063/.
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Climate change associated with increasing concentrations of the greenhouse gas, carbon dioxide(CO2), is expected to lead to an increase in global mean temperature of between 1 and 3.5 deg C by the end of the 21st century, with regional changes in rainfall and humidity. This thesis is concerned with modelling the effects of a changing climate and atmospheric C02 concentration on global vegetation. The process-based model, DOLY (Dynamic glObal phtogeographY), is used. It is able to operate using three climate variables, two soil variables and an atmospheric CO2 concentration. Its outputs are leaf area index (LAI), and net primary productivity (NPP). The LAI and NPP values predicted by DOLY were used to run a life-form model with a climate change scenario. It was found that warming led to the spread of trees into the tundra region. The DOLY model was also coupled with the Hadley Centre general circulation model to determine the feedbacks of vegetation on climate. With a global warming of 2◦C, the global feedback of vegetation on temperature was a decrease of 0.1 deg C. However at the regional scale the feedback was +/-2 ◦C, of similar magnitude to the driving temperature change. Finally, the DOLY model was run with transient climate data from the Hadley Centre. The boreal forest moved north, and the Gobi desert and the southern steppes in the former Soviet Union shrank in area. The sensitivity of the model to its soil and climate inputs have also been analysed over a range of environments and the model has been validated with reference to satellite data and experimental data. It was found to perform well. This thesis has shown that it is possible to predict current and possible future distributions of vegetation with climate change using a vegetation model.
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Hughes, Peter Samuel. "A strategy for reducing emissions of greenhouse gases from personal travel in Britain". Thesis, n.p, 1992. http://oro.open.ac.uk/19843/.
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Builes, Toro Santiago. "Understanding the behavior of materials for caputre of greenhouse gases by molecular simulations". Doctoral thesis, Universitat Autònoma de Barcelona, 2012. http://hdl.handle.net/10803/83951.
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Establecer una cota global a las emisiones de gases de efecto invernadero ha sido imposibilitado
por la complejidad que conlleva demostrar los efectos de la contribución humana al efecto
invernadero. Para alcanzar un desarrollo sostenible es necesario, primero limitar y en lo posible
eliminar las emisiones de dichos gases a la atmosfera. En este contexto, la adsorción de gases se
ha establecido como una de las alternativas más efectivas a mediano plazo para la reducción de
emisiones de gases de efecto invernadero. Por lo tanto, en esta tesis, el objetivo principal es
estudiar a nivel molecular la adsorción de gases de efecto invernadero y comprender mejor la
interacción entre las distintas variables que afectan el proceso de captura.
En la primera parte de esta tesis se estudió, la separación de una mezcla de hexafluoruro de
azufre (SF6) y nitrógeno (N2). El SF6 se emite en pequeñas cantidades, sin embargo por ser un
potente gas de efecto invernadero con un tiempo de vida extremadamente alto se requiere un
control estricto de sus emisiones. En este trabajo se estudió, empleando modelos simples, el
efecto del tamaño de poro, la presión y la composición de la mezcla en la separación selectiva
del SF6. Posteriormente, se realizaron simulaciones con modelos realistas de dos carbonos
réplicas de zeolitas y se encontró que la selectividad predicha para el SF6 en dichos materiales es
superior a la de los materiales previamente reportados en la literatura.
En la segunda parte del trabajo se estudió el uso de estos materiales de carbono para la captura
de dióxido de carbono (CO2) a temperatura ambiente, y se encontró que su capacidad de
captura de CO2 a altas presiones es comparable a la de los mejores adsorbentes de CO2
reportados. Para comprender mejor la captura en los carbonos réplicas de zeolitas, se
emplearon simulaciones moleculares para obtener información acerca de su compleja
estructura interna y predecir las interacciones del CO2 con el interior de estos materiales.
En la parte final de esta tesis se estudiaron materiales híbridos organo-inorgánicos, en
particular, adsorbentes de sílica funcionalizados con grupos amino. Se desarrolló una nueva
metodología de simulación para la generación de materiales de sílica funcionalizados con
cadenas orgánicas y el cálculo de sus propiedades de adsorción. La metodología se evaluó
empleando modelos de sílica gel y MCM-41 funcionalizados con diferentes cadenas orgánicas,
comparando los resultados de las simulaciones de las isotermas de adsorción y la densidad de
funcionalización con datos experimentales. Simultáneamente, se desarrolló un nuevo método
que permite calcular adicionalmente a la fisisorción la quimisorción del CO2 en las aminas
empleando simulaciones moleculares.
En resumen, esta tesis de doctorado resalta diferentes posibilidades para la captura y
separación de gases de efecto invernadero y proporciona nuevas herramientas de simulación
para evaluar y optimizar sistemas de captura de gases. Esta tesis se enmarca dentro de la ciencia
de materiales y muestra como la investigación básica en este campo puede ser usada como una
herramienta para evaluar y optimizar procesos industriales.The establishment of a global limit on the emissions of greenhouse gases has been hindered by the complexity to prove the effects of manmade greenhouse gases on a global scale. In order to achieve a sustainable development it is important to limit, and when possible eliminate, emissions of industrial greenhouse gases to the atmosphere. In this context, adsorption has been established as one of the best cost-effective means of reducing emissions of greenhouse gases in the short-term. Thus, in this thesis, the main objective is to study at a molecular level the adsorption of greenhouse gases and to obtain a better insight into the capture processes for their future optimization. Molecular simulations are used in order to find the optimal diameter for the separation of sulfur hexafluoride (SF6) from nitrogen (N2); this mixture is commonly used in electrical applications. SF6 is typically emitted in small quantities, but because it is a potent greenhouse gas and possesses extremely long lifetimes, there is a pressing need for a strict control of its emissions. The effect of pore size, pressure, and mixture compositions on the selective adsorption of SF6 was investigated using simple models. Subsequently, simulations using two atomistic models of zeolite templated carbons were performed. The separation selectivities compared favorably to the materials previously reported for the separation of this mixture. Moreover, the potential use of these two templated carbon materials to capture carbon dioxide (CO2) at room temperature is reported. Their high-pressure CO2 adsorption isotherms are among the highest carbon capture capacity for carbonaceous materials and are comparable to the best CO2 adsorbing materials. In addition, the simulated adsorption isotherms were used to obtain new insights into the adsorption process of the templated carbons. In the final part of the thesis hybrid organic-inorganic adsorbents were studied. For CO2 capture, solid adsorbents are functionalized with amino groups that largely increase their adsorption capabilities. However, the underlying mechanism of the adsorption process in the functionalized materials is not fully understood, limiting the possibility of designing optimal adsorbent materials for different applications. The adsorption of CO2 in aminefunctionalized silica materials was studied using Monte Carlo molecular simulations. A simulation methodology for the design of functionalized silica materials was proposed. The methodology was evaluated using models of silica gel and MCM-41 functionalized with different organic groups, comparing the resulting adsorption isotherms and grafting density to available experimental data. Furthermore, a new scheme that allows accounting for the chemisorbed CO2 on the adsorption isotherms is presented In summary, this PhD thesis highlights different possibilities for the capture and separation of greenhouse gases and provides new tools for evaluating and optimizing capture systems. Finally, this dissertation shows the use of basic research in Materials Science as an established tool for evaluating and optimizing thermodynamics of engineering processes.
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Tran, Julie. "Greenhouse gases embodied in international trade : an input-output analysis for Canada : 2002". Thesis, University of British Columbia, 2011. http://hdl.handle.net/2429/39774.
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Both climate change and actions to fight it are occurring against rapidly expanding international trade flows, which increasingly lead to the separation of production and consumption patterns. Through the trade of goods in a globally interdependent world, the consumption in each country is linked to greenhouse gases (GHG) emissions in other countries because GHGs are emitted throughout the supply chain involved in producing those goods; a phenomenon referred to as ‘embodied GHG’.
In this research, taking a consumption-based approach and using an environmental input-output analysis, I explore the amount of GHGs embodied in Canada’s imports and export for the year 2002 and determine that Canada has a negative balance of embodied emissions in trade (BEET). This implies that the GHGs emitted in connection with the production of exported goods surpass those emitted in connection with the production of imported goods. In light of Canada’s large trade surplus in 2002, my finding support the hypothesis that there may be an inherent conflict between a national GHG reduction target for domestic emissions and the aims of improving trade balances or maintaining trade surpluses.
While my negative BEET result holds under different model specifications (i.e., single-country or multi-country model), I also show that it is highly dependent on the exchange rate used to convert the value of Canadian imports from the U.S. into the U.S. currency. Thus, my results demonstrate the weakness of using monetary flows of merchandise trade when trying to estimate physical quantities, in this case, the amount of GHGs embodied in the traded goods. Finally, I also discuss some of the key intersections between climate and trade policies, with a particular focus on climate policies that attempt to link the consumption of goods in a country with the amount of GHGs emitted during their production, whether in that country or elsewhere.
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Ganesan, Anita Lakshmi. "Quantifying emissions of greenhouse gases from South Asia through a targeted measurement campaign". Thesis, Massachusetts Institute of Technology, 2013. http://hdl.handle.net/1721.1/82307.
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Thesis (Ph. D. in Climate Physics and Chemistry)--Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences, 2013.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 161-167).
Methane (CH 4 ), nitrous oxide (N20) and sulfur hexafluoride (SF6) are powerful greenhouse gases with global budgets that are well-known but regional distributions that are not adequately constrained for the purposes of mitigation and policy initiatives. Quantifying emissions using inverse approaches at the national scale requires measurements that specifically target the region of interest. Primarily due to the lack of atmospheric measurements from the region, emissions estimates of these greenhouse gases from India have largely been missing. New in situ measurements of atmospheric mole fractions from a Himalayan station in Darjeeling, India (27.03'N, 88.26'E, 2200 meters above sea level) have been collected from December 2011 for CH4 and March 2012 for N20 and SF6 to February 2013 using high-precision instrumentation that is linked to the Advanced Global Atmospheric Gases Experiment (AGAGE). These measurements comprise the first high-frequency dataset of these gases collected in India and are used for measurement-based assessment of emissions. Several features are identified. In SF6 , the signal associated with Northern Hemispheric background is typically present. CH4 and N20 mole fractions are almost always enhanced over the background, suggesting strong regional sources. Additionally, a diurnal signal resulting from thermally driven winds is seasonally present. A particle dispersion model is used to track 'air histories' of measurements, quantifying the sensitivity of concentrations at Darjeeling to surface emissions. The effect of topography on the derived air histories is investigated to test the robustness of the model in simulating transport in this complex environment. The newly acquired data set is used to investigate the ability of the model to reproduce signals that stem from the mesoscale diurnal winds. The sensitivities of meteorological resolution and particle release height are investigated to better quantify some of the uncertainties associated with this chemical transport model. A Quasi-Newton inverse method is used to estimate emissions at monthly resolution. CH4 , N20 and SF6 emissions from India are found to be 44.3% Tg yr- 1, 825 1045/707 GgN yr- 1 and 221 241/205 kton yr-', respectively. Significant uncertainty reduction is seen on emissions from India during the summer when the monsoon results in high sensitivity over the subcontinent.
by Anita Lakshmi Ganesan.
Ph.D.in Climate Physics and Chemistry
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Novais, Sarah Vieira. "Biochars in the mitigation of greenhouse gases and on phosphorus removal and reuse". Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/11/11140/tde-10052018-170240/.
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Measures aimed at mitigating environmental impacts, especially the anthropic ones, are being progressively studied. Increasing greenhouse gases (GHG) emissions are among the biggest environmental problems in the world, with agriculture one of the major contributors to this impact. Water eutrophication from land misuse and agricultural systems also fits into such a scenario of concern. Biochar, the product of the pyrolysis of organic materials, appears as a recover of a list of environmental problems, among them the mitigation of GHG and the recovery of eutrophic or wastewater. In this sense, biochars of sugarcane straw (BCS) and poultry manure (BPM) were used in GHG emission tests in soils with contrasting textures. To do so, two pyrolysis temperatures (350 and 650 °C), three doses (12.5, 25 and 50 Mg ha-1), two texture classes (sandy and clayey) and two pH values (original pH and pH 5.5) were used. These same biochars were submitted to doping processes pre-pyrolysis with Mg2+ and post-pyrolysis with Al3+ for the adsorption of phosphorus (P). Desorption and adsorption experiments in competition with other anions by the exchange sites were done. The potential GHG mitigation of both biochars has been proven in the gas emission tests. The increase of the pyrolysis temperature (350 to 650 °C) further increases the gas mitigation, and the acidification of the original pH of the biochar causes a similar effect. The benefits of pyrolyzing such organic materials are best seen in sandy soil, with the production of biochar from these residues being an environmentally safe way of depositing these materials, at least with regard to the emission of GHG. Both biochars do not have P adsorption capacity without passing through chemical modification, and the doping process, with Mg or Al, granted this ability. The pre-doping process with Mg2+ generated a P maximum adsorption capacity (PMAC) of 250.8; 163.6; 17.7; 17.57 mg g-1 for the pyrolyzed BPM at 350 and 650 °C and for the BCS also pyrolysed at 350 and 650 °C, respectively. The post-doping process with Al3+ generated a PMAC of 701.6 and 758.9 mg g-1 for BPM and BCS, both of which were pyrolysed at 350 °C, respectively. The superior PMAC of the Al doped biochars was attributed to the fact that the cation that makes the bridge (Al3+) is trivalent, with high affinity for P. The high adsorption of Al by the biochars corroborates with such a statement. Both biochars, produced by the two doping processes, had a desorption of P around 80 % of the adsorbed value, allowing the inference that these products have the capacity to be used in nutrient reuse, mitigating another environmental problem: the use of the finite reserves of P. With the positive results coming from the pyrolysis of the materials in this thesis, we certify the biochar potential as a GHG mitigator, recovery for waters and a potential slow release fertilizer in P reuse.Medidas que visam a mitigação de impactos ambientais, especialmente os antrópicos, estão sendo cada vez mais estudadas. A crescente emissão de gases de efeito estufa (GEE) está entre os maiores problemas mundiais, sendo a agricultura um dos grandes contribuintes para este impacto. A eutrofização de águas, ocasionada pelo mau uso do solo e dos sistemas agrícolas, também se encaixa em tal cenário de preocupação. O biocarvão, produto da pirólise de materiais orgânicos, aparece como recuperador de uma lista de problemas ambientais, dentre eles a mitigação de GEE e a recuperação de águas eutrofizadas ou residuárias. Neste sentido, biocarvões de palha de cana-de-açúcar (BPC) e de dejeto de galinha (BDG), foram utilizados em ensaios de emissão de GEE em solos com texturas contrastantes. Para tal, duas temperaturas de pirólise (350 e 650 °C), três doses (12,5; 25 e 50 Mg ha-1), duas classes texturais (arenoso e argiloso) e dois pHs (pH original e pH 5.5), foram utilizados. Estes mesmos biocarvões foram submetidos a processos de dopagem pré-pirólise com Mg2+ e pós-pirólise com Al3+ para a adsorção de fósforo (P). Ensaios de dessorção e de adsorção em competição com outros ânions pelo sítio de troca foram feitos. O potencial mitigador de GEE de ambos os biocarvões foi comprovado nos ensaios de emissão de gases. O aumento da temperatura de pirólise (350 para 650 °C) eleva ainda mais a mitigação dos gases, sendo que a acidificação do pH original do biocarvão causa efeito semelhante. Os benefício de se pirolisar tais materiais orgânicos são melhores vistos no solo arenoso, sendo a produção de biocarvão a partir destes resíduos uma forma ambientalmente segura de deposição destes materiais, ao menos no que se diz respeito a emissão de GEE. Ambos os biocarvões não possuem capacidade de adsorção de P sem passar por modificação química, sendo que o processo de dopagem, seja ele com Mg ou Al, concedeu tal habilidade. O processo de pré-dopagem com Mg2+ gerou uma capacidade máxima de adsorção de P (CMAP) de 250,8; 163,6; 17,7; 17,6 mg g-1 para o BDG pirolisado a 350 e 650 °C e para o BPC também pirolisado a 350 e 650 °C, respectivamente. O processo de dopagem por pós-pirólise com Al3+ gerou uma CMAP de 701,6 e 758,9 mg g-1 para o BDG e BPC, ambos pirolisados a 350 °C, respectivamente. A superior CMAP dos biocarvões dopados com Al foi atribuída ao fato de o cátion que faz a ponte (Al3+) ser trivalente, com elevada afinidade pelo P. A elevada adsorção de Al pelos biocarvões corrobora com tal afirmação. Ambos os biocarvões, produzidos pelos dois processos de dopagem, tiveram uma dessorção de P em torno de 80 % do valor adsorvido, permitindo a inferência de que estes produtos possuem a capacidade de serem utilizados no reuso de nutrientes, mitigando outro problema ambiental: o uso das reservas finitas de P. Com os resultados positivos advindos da pirolisação dos materiais nesta tese, constatamos o potencial do biocarvão como mitigador de GEE e recuperador de águas.
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Dias, Lívia Cristina Pinto. "Patterns of land use and greenhouse gases emissions from Brazilian agriculture (1940-2014)". Universidade Federal de Viçosa, 2017. http://www.locus.ufv.br/handle/123456789/11612.
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Conselho Nacional de Desenvolvimento Científico e Tecnológico
Dada a grande extensão do Brasil, sua enorme diversidade de vegetação e heterogeneidade agrícola, o desenvolvimento de políticas agrícolas e de conservação requer uma compreensão dos padrões históricos de uso da terra para todo o país. Somente através da lente da história que as atuais tendências geográficas no uso da terra podem ser totalmente compreendidas e projeções futuras mais precisas podem ser feitas. Este estudo analisa os padrões espaciais da agricultura brasileira entre 1940 e 2014, com ênfase no uso da terra e nas emissões de gases de efeito estufa. Os padrões históricos de uso das terras pela agricultura e emissões de gases de efeito estufa foram investigados usando uma nova base de dados histórico-espacial com resolução espacial de 30” (aproximadamente 1 km x 1 km). Embora a fronteira agrícola ainda esteja expandindo na Amazônia e Cerrado, as taxas são muito menores do que antes, e em toda a parte oriental e sul do país, a área agrícola está diminuindo. A produção de soja e milho aumentou devido ao aumento da área e da produtividade, mas a produção de cana-de-açúcar aumentou principalmente devido à extensificação. As pastagens diminuíram em todas as regiões analisadas, exceto na Amazônia, mas o lento processo de transferência de tecnologia tem mantido a taxa de lotação de bovinos perto de 1 cabeça/ha, indicando um sistema de pecuária ineficiente. O Brasil está se movendo lentamente para uma agricultura mais intensiva e sustentável. Até 1975, o desmatamento da Mata Atlântica e do Cerrado foram as principais fontes de emissões de CO 2 pela mudança de uso da terra. Depois disso, a Amazônia tomou a primeira posição como fonte de emissões de CO 2 . As emissões decorrentes da mudança do uso da terra na Mata Atlântica e nos Pampas diminuíram gradualmente após 1975 e esses biomas tornaram-se sumidouros de CO 2 desde 1990. As emissões agrícolas totais estão diminuindo porque as emissões de CO 2 estão diminuindo e elas são várias vezes maiores (em termos de CO 2eq ) que as emissões de CH 4 e N 2 O. Por outro lado, o aumento da produtividade resulta em aumento das emissões pela agricultura. Brasil está a caminho da redução das emissões por uso do solo propostas na Política Nacional sobre Mudanças no Clima. Sobre as Contribuições Nacionalmente Determinadas no acordo de Paris, em 2015, as taxas passadas de restauração florestal são mais do que suficiente para atingir a medida sugerida no acordo. A conclusão é que o Brasil deveria ser mais audacioso em suas metas. Esses resultados fornecem uma das primeiras visões históricas abrangente e espacialmente explicita do uso da terra pela agricultura e pecuária das emissões de gases de efeito estufa no Brasil, fornecendo ideias claras para orientar futuros planejamentos territoriais, a agricultura sustentável, a formulação de políticas públicas e a tomada de decisões.
Given the large size of Brazil, its enormous vegetation diversity and agriculture heterogeneity, the development of national agricultural and conservation policies requires an understanding of historical patterns of land use for the entire country. It is only through the lens of history that the current geographic trends in land use can be fully understood and accurate future projections made. This study analyzes the spatial patterns of the Brazilian agriculture between 1940 and 2014, with emphasis on land use and greenhouse gas emissions. I investigate the historical patterns of agricultural land use and greenhouse gases emissions in Brazil using a new historical-spatial database at spatial resolution of 30” (approximately 1 km x 1 km). Although the agriculture frontier is still expanding in the Amazon and Cerrado, rates are much lower than before, and throughout the eastern and southern part of the country, agricultural land use is actually decreasing. The production of soybean and maize increased due to increase in area and yields, but the production of sugarcane increased predominantly due to extensification. Pasturelands decreased in all regions analyzed, except in Amazonia, but the slow process of technology transference appears to be keeping the Brazilian stocking rate of cattle close to 1.0 head/ha, indicating an inefficient livestock system. Brazil is moving slowly towards a more intensive and sustainable agriculture. Until 1975, deforestation of the Atlantic Forest and Cerrado were the main sources of CO 2 emissions. After that, Amazonia took the first position as source of CO 2 emissions. Emissions from land use change in Atlantic Forest and Pampas decreased gradually after 1975 and these biomes become a sink of CO 2 since 1990. The total agricultural emissions are decreasing because the CO 2 emissions are decreasing and they are several times larger (in CO 2eq terms) than the CH 4 and N 2 O emissions. Brazil is heading towards the reduction of land use change emissions as proposed in the National Policy on Climate Change. About the Nationally Determined Contributions proposed in the 2015 Paris agreement, the past rates in forest restoration are more than sufficient to achieve the suggested measure proposed. The conclusion is that Brazil should be more audacious in its goals. My results provide one of the first comprehensive historical and geographically explicit overview of agricultural land use and greenhouse gases emissions in Brazil, providing clear insights to guide future territorial planning, sustainable agriculture, policy and decision-making.
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Marinheiro, Joana Filipa Jorge. "Quantification of greenhouse gas emissions from the biodegradation of garden waste". Master's thesis, ISA, 2019. http://hdl.handle.net/10400.5/19478.
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Mestrado em Engenharia do Ambiente - Instituto Superior de AgronomiaThe primary aim of this study was to quantify garden waste potential for GHG emissions (with focus on CH4 and N2O); and to identify relationships between these GHG emissions and meteorological variables in different climates. The study was carried out in two countries with contrasting climates and soil structures: Portugal with a Mediterranean climate and Scotland with a hyperoceanic climate. A closed static chamber methodology was used for measure N2O and CH4 gaseous flux in three types of treatments installed in containers kept outdoors: S with soil; S+GW with soil and garden waste layered on top; and GW with only garden waste. The range of N2O fluxes varied on a log-normal scale, ranging from slightly negative values to very high values (3 orders of magnitude). With the exception of the “control” S treatments (maximum flux of 0.54 N2O nmolm-2s-1 at both sites). The percentage of the emitted CO2 equivalent (CO2eq) from the original C content applied to the treatments as garden waste indicates the overall impact on emissions of the composting process. Based on CO2eq global warming potential (GWP) multipliers stated by the IPCC (2014) (25 for CH4 and 298 for N2O), Portugal emitted 28.47% from the treatment S+GW and 11.26% from GW, while the majority of the C remained on soils (>70%). Scotland’s treatment S+GW had a lower CO2eq emission of 11.99%, with 58.47% emitted from the GW treatment. These results show that the overall impact on GWP of composting varies dramatically depending on management, and that CO2 is being converted into considerably high quantities of longer lived GHGs like CH4 and N2O. Cumulative CH4 flux measurements showed sequestration in Portugal and emissions in Scotland, the effects were more pronounced in treatment S for both sites (-210.85 and 209.0519 mgCH4m-2d-1, respectively). The garden waste diminished the emissions for Scotland and hindered the sequestration for Portugal. The contribution of weather conditions from each site was significant and very different relatively to the behaviour of each GHG. Portugal had constant moderate/high temperatures with peaks of rain which stimulated the GHG; Scotland on the other hand had constant rain with low temperatures with occasional rises which was the controlling factor stimulating the GHG
N/A
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Gupta, Manish. "Restricting greenhouse gas emissions : economic implications for India /". New Delhi : Serials Publ, 2006. http://www.gbv.de/dms/zbw/522298486.pdf.
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Nariman, Mostafavi Seyed. "Literature Review and Analysis of Greenhouse Gases in the LEED Rating Program : A review of the currently available literature with regards to greenhouse gas calculations for green buildings". Thesis, KTH, Industriell ekologi, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-108292.
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Choi, Chuen-yin, i 蔡雋妍. "Combating climate change: the control of greenhouse gas emissions in Hong Kong". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2012. http://hub.hku.hk/bib/B50254856.
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Assunção, Marcelo Henrique Correa [UNESP]. "Emissões de gases do efeito estufa em sistemas multitróficos de aquicultura". Universidade Estadual Paulista (UNESP), 2017. http://hdl.handle.net/11449/150932.
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
O objetivo deste estudo foi investigar o fluxo de gases do efeito estufa (GEE) em viveiros de criação de organismos aquáticos. Nós testamos se o uso de sistemas multitróficos e multiespaciais (IMTA), povoados com lambari-do-rabo-amarelo (Astyanax lacustris) e camarão-da-amazônia (Macrobrachium amazonicum) numa região tropical, altera o fluxo de gases do efeito estufa em comparação com um sistema de monocultivo de A. lacustris. Nós desenvolvemos um experimento em viveiros de fundo natural com três tratamentos e quatro réplicas: monocultivo (Tetra), IMTA livre (Free IMTA) e IMTA tanque rede (Cage IMTA). O experimento durou 68 dias, entre os meses de novembro e janeiro de 2016. Nós mensuramos os fluxos de dióxido de carbono (CO2), metano (CH4) e óxido nitroso (N2O) por meio das metodologias difusiva e dissolvida. A média dos fluxos na metodologia difusiva foi de -8.93 mg.m-2.h-1 para o CO2, -0.88 mg.m-2.h-1 para o CH4 e 1.78 mg.m-2.h-1 para o N2O. A concentração de CO2 variou de 0.0481 a 0.6668 mg.L-1, CH4 de 0.0003 a 0.0053 mg.L-1 e N2O de 0.0789 a 0.1177 mg.L-1. Nossos resultados indicam variação ao longo do tempo, com maior fluxo de GEE no início do experimento, diminuição ao longo do período de cultivo e tendência de neutralidade com relação a emissão de GEE no final do período experimental.
CNPq: 147409/2013-6
CNPq: 473199/2011-4
CNPq: 306361/2014-0
FAPESP: 2012/18593-5
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Hyman, Robert C., John M. Reilly, Mustafa H. M. Babiker i Masin Ardoin De. "Modeling non-CO₂ greenhouse gases". 2002. http://hdl.handle.net/1721.1/3617.
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Although emissions of CO₂ are the largest anthropogenic contributor to the risks of climate change, other substances are important in the formulation of a cost-effective response. To provide improved facilities for addressing their role, we develop an approach for endogenizing control of these other greenhouse gases within a computable general equilibrium (CGE) model of the world economy. The calculation is consistent with underlying economic production theory. For parameterization it is able to draw on marginal abatement cost (MAC) functions for these gases based on detailed technological descriptions of control options. We apply the method to the gases identified in the Kyoto Protocol: methane (CH4), nitrous oxide (N2O), sulfur hexaflouride (SF6), the perflourocarbons (PFCs), and the hyrdoflourocarbons (HFCs). Complete and consistent estimates are provided of the costs of meeting greenhouse-gas reduction targets with a focus on "what" flexibility — i.e., the ability to abate the most cost-effective mix of gases in any period. We find that non-CO2 gases are a crucial component of a cost-effective policy. Because of their high Global Warming Potentials (GWPs) under current international agreements they would contribute a substantial share of early abatement.Abstract in HTML and technical report in PDF available on the Massachusetts Institute of Technology Joint Program on the Science and Policy of Global Change website (http://mit.edu/globalchange/www/).
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Chen, Yi-Wen, i 陳意雯. "A Study of Using Low Greenhouse Effect Gases as Tracer Gases". Thesis, 2015. http://ndltd.ncl.edu.tw/handle/89741401656780697260.
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碩士長榮大學
職業安全與衛生學系碩士班
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Sulfur hexafluoride (SF6) is often used as the tracer gas to determine the performance of general ventilation or local exhaust ventilation, although SF6 is stable, non-toxic, incombustibly and non-existing substance in nature. It looks perfect to meet the requirement of being a tracer gas, but it has high global warming potential (GWP) 22,800 and great potential hazard to the environment. The global warming situation became more serious in recent years. We have to find other gases to replace SF6 as the tracer gas. Recent researches discussed the possible chemicals to replace SF6 as the tracer gases, which included nitrous oxide, tetrafluoroethane, FM-200, acetic acid, ethylene, carbon dioxide etc. Based on the recent researches, and under the consideration of the lower GWP of Intergovernmental Panel on Climate Change (IPCC), lower permission exposure limit (PEL), and lower explosive limit (LEL), we decided to choose tetrafluoroethane, nitrous oxide, acetone, isopropyl alcohol, butane for this study. In this study, we used the chemical fume hood as the testing target, which was set to 2 different flowrates, then followed the static sash test method of EN 14175-3:2003 and used different instruments to measure the concentrations of the challenge gases in triplicate. Finally, the comparison of each gas and SF6 was made on R, GWP, cost, and convenience of instruments. The conclusion of all the experimental data, indicated that the best correlation with SF6 was acetone. The GWP of acetone is 0.25, it can reduce surface absorption of infrared light, and mitigate the effects of global warming on the environment. The cost of acetone is cheap. Photo ionization detector (PID) can be used to measure acetone and has the characteristics of easy operation and carry. Also, acetone had similar gas behaviors of SF6 at beneath layer of the hood. The results of this study indicated that acetone was the most suitable tracer gas as the replacement of SF6.