Dissertations / Theses on the topic 'Carbon dioxide – Mathematical models'
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Kasturirangan, Anupama. "Specific interactions in carbon dioxide + polymer systems." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/22570.
Full textCommittee Chair: Dr Amyn.S.Teja; Committee Member: Dr Haskell Beckham; Committee Member: Dr Peter. J. Ludovice; Committee Member: Dr William.J.Koros; Committee Member: Dr. Thomas H. Sanders.
Thompson, Christopher David. "An analytical and experimental investigation of respiratory dynamics using P/D control and carbon dioxide feedback." Thesis, Virginia Tech, 1988. http://hdl.handle.net/10919/43059.
Full textMaster of Science
Briesemeister, Roberta. "Modelagem matematica para o estudo do oidio em uma plantação de soja sob os efeitos do CO2." [s.n.], 2007. http://repositorio.unicamp.br/jspui/handle/REPOSIP/307575.
Full textDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Matematica, Estatistica e Computação Cientifica
Made available in DSpace on 2018-08-08T21:33:03Z (GMT). No. of bitstreams: 1 Briesemeister_Roberta_M.pdf: 814655 bytes, checksum: bf6c5b877276e48f013d98984a004dde (MD5) Previous issue date: 2007
Resumo: As recentes mudanças climáticas no planeta, estão promovendo alterações na ocorrência e desenvolvimento de doenças de plantas. O principal gás causador desse acontecimento é o dióxido de carbono, CO2. Baseado neste fato, foi desenvolvido pela Embrapa Meio Ambiente, um experimento que trabalha com cenários futuros, tendo em vista a quantidade de CO2 presente na atmosfera. Preliminarmente foi feita uma análise estatística dos dados, verificando a área foliar lesionada, a altura das plantas primárias de soja, a nodulação e o peso seco. Com os resultados obtidos nessa análise, observamos que havia uma diferença significativa no tamanho da área foliar lesionada quando exposto a níveis diferentes de CO2. À partir desses dados, foi elaborado um modelo matemático determinístico para a previsão do crescimento da área foliar lesionada, causada pelo oídio, acoplando na taxa de crescimento da lesão a influência da quantidade de CO2. Algumas simulações foram feitas utilizando o crescimento da quantidade de CO2 da atmosfera. Com os dados existentes de anos anteriores, observamos em todos os casos, que altos níveis de CO2, provocam uma diminuição na área foliar lesionada. Muito embora exista uma diminuição nessa área, a quantidade do patógeno cresce exponecialmente no tempo. O que nos faz concluir, que em cenários futuros, haverá uma grande dissiminação na doença da soja, provocada pelo oídio
Abstract: The recently climate changes of the planet are promoving alteration in the incident and development in the plants diseases. The main gas that cause this event is the carbon dioxide, CO2. Based in this fact, it was developed by Embrapa environmental, the experiment that works with futures scenarios, looking the quality of CO2 present in the atmosphere. First of all it was made a statistic analyses of datas, verifing the leaf area that was damned, the hights of the primary soybeans plants, the nodulation and the dry weight. With the results that was gotten in this analyses, we could notice that it had a significant difference in the size of the leafs area damned when it was expose in differents levels of CO2. Starting from this datas, it was elaborated a deterministical mathematic model for crop the growing leaf area damned, caused by mildew, coupled in the growing rate of the damned area the influence of the CO2 quantity. Some simulation it were done using the growing quantity of CO2 in the atmosphere. With the presents datas of the years, we observe that in all cases, that hight level of CO2 cause the reduction of the damned leafs area. Even thought exists a reduction in this area, the quantity of pathogen grows exponentially in the times. What make us conclude, that in futures scenarios, will have a big spread in the soybean disease, caused py mildew
Mestrado
Mestre em Matemática Aplicada
Chiang, Yang-Sheng. "Estimating landscape level leaf area index and net primary productivity using field measurements, satellite imagery, and a 2-D ecophysiological model." Virtual Press, 2004. http://liblink.bsu.edu/uhtbin/catkey/1294241.
Full textDepartment of Natural Resources and Environmental Management
Powell, James Eckhardt. "Building a Multivariable Linear Regression Model of On-road Traffic for Creation of High Resolution Emission Inventories." PDXScholar, 2017. https://pdxscholar.library.pdx.edu/open_access_etds/3415.
Full textPinto, Taborga Carola. "A methodology and a mathematical model for reducing greenhouse gas emissions through the suppply chain redesign." Doctoral thesis, Universitat Politècnica de Catalunya, 2018. http://hdl.handle.net/10803/620787.
Full textPrácticamente toda la comunidad científica, política, comercial y social es consciente de la importancia del desafío medio ambiental relacionado con las emisiones de Gases de Efecto Invernadero (GEi). Los paises adheridos al Protocolo de Kioto han asumido el desafío de reducir los GEi, implementando políticas que incluyen programas de comercio de emisiones , programas voluntarios, impuestos sobre la emisión de GEi y normas sobre eficiencia energética. En este contexto, el mundo empresarial debe ser capaz de generar una estrategia de reducción de GEi para garantizar el éxito a largo plazo, considerando además que los clientes están cada vez más interesados en el bienestar del medio ambiente . Esta tesis ha abordado el problema de diseñar (o rediseñar) la cadena de suministro como vía para la reducción de GEi de una manera económicamente viable y, en la medida de lo posible, óptima. La tesis aborda la problemática diseñando una metodología completa y formalizada, que incluye también un modelo matemático para determinar las mejores decisiones a tomar. De la revisión de la literatura, se ha concluido que, si bien existen autores que proponen modelos relacionados con el diseño de la cadena de suministro que incluyen la reducción de GEi, no existen trabajos que propongan una metodología completa y suficientemente formalizada que puedan ser aplicados a la realidad. La metodología consta de 4 etapas que son: 1) La creación de una estrategia corporativa para la reducción de GEi; 2) La alineación con la planificación financiera estratégica; 3) El desarrollo de un modelo matemático; y 4) La implementación y seguimiento. En la primera etapa se desarrolla una guía de seis pasos para crear una estrategia corporativa para la reducción de GEi, los pasos son: 1) Determinar el tipo de emisión; 2) Definir el alcance; 3) Establecer las bases de la medición; 4) Identificar oportunidades de reducción de GEi; 5) Establecer los objetivos; 6) Planificar la participación en programas de reducción de GEi. En la segunda etapa, la estrategia corporativa antes propuesta, se evalúa desde un punto de vista financiero y se integra en la planificación estratégica. En la tercera etapa, se propone un modelo de Programación Lineal Entera Mixta para obtener un plan para et rediseño de ta cadena de suministro, de modo que: 1) se logren tos objetivos de reducción de GEi; 2) se tenga en cuenta el plan financiero estratégico; 3) se contemplen todas las posibilidades reales para rediseñar la cadena de suministro; y 4) se optimicen tos resultados económicos de la empresa. La metodología, incluyendo el programa matemático se ha probado en tres casos de estudio. El primer caso de estudio corresponde a una multinacional del sector de productos de higiene del hogar y cuidado personal que opera en Brasil, donde el modelo matemático fue adaptado para integrar beneficios fiscales. El segundo caso trata de una multinacional del sector alimentario basada en España que requiere un rediseño de la cadena de suministro para mejorar el coste de producir. Finalmente, en el tercer caso se utiliza una empresa del sector del metal basada en EE. UU., para ilustrar la importancia de la definición de límites y responsabilidades corporativas . En los tres casos de estudio, el modelo matemático maximiza el beneficio neto mientras alcanza el objetivo de reducción de GEi. Por lo tanto, la metodología es útil para conseguir beneficios económicos y medio ambientales, además de brindar beneficios relacionados con la mejora de la imagen corporativa, fortalecimiento de las marcas y el evitar posibles riesgos impositivos . En conclusión, la metodología propuesta fue desarrollada para que su implementación pueda generar en las empresas una ventaja competitiva y un crecimiento fundamentado en la sostenibilidad ambiental; asimismo, fue diseñada para que sea lo suficientemente flexible y pueda adaptarse a las necesidades de cada negocio
Li, Zhe 1974. "The environmental Kuznets curve reexamined for CO₂ emissions in Canadian manufacturing industries /." Thesis, McGill University, 2004. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=80319.
Full textMcLellan, Bradley John. "Development of an Intraruminal Controlled-Release Device." The University of Waikato, 2007. http://hdl.handle.net/10289/2527.
Full textDjalilvand, Hamid. "Growth response of Pinus resinosa and Picea abies to past and future climatic variations." Thesis, McGill University, 1996. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=23997.
Full textThe JABOWA model was used to predict tree growth in hypothetical climates which could result from global climate changes. Based on literature, five treatments were applied: normal, and increases of 1, 3, 5, and 10$ sp circ$C. Comparison between the last (1983-1992) and next (1993-2002) ten years growth showed no significant differences between species when temperature was normal or increased by 1 and 3$ sp circ$C, but significant differences between species were observed when the temperature was increased by 5$ sp circ$C. Both species declined when the temperature was increased by 10$ sp circ$C. We concluded that Norway spruce is more sensitive to increases in atmospheric temperatures than red pine at our site.
Mitchell, Mark J. "Mathematical modelling of carbon dioxide dissolution and reaction processes." Thesis, University of Nottingham, 2012. http://eprints.nottingham.ac.uk/14502/.
Full textGrote, Matthew John. "Enhancing urban road traffic carbon dioxide emissions models." Thesis, University of Southampton, 2017. https://eprints.soton.ac.uk/412711/.
Full textMartin, M. J. "Models of the interactive effects of rising ozone, carbon dioxide and temperature on canopy carbon dioxide exchange and isoprene emission." Thesis, University of Essex, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.339238.
Full textDombek, Priscilla Emily 1961. "IMPROVING THE CONVERSION OF THE SULFUR DIOXIDE - LIME REACTION BY USING ADDITIVES." Thesis, The University of Arizona, 1986. http://hdl.handle.net/10150/291523.
Full textMoloney, Coleen Lyn. "A size-based model of carbon and nitrogen flows in plankton communities." Doctoral thesis, University of Cape Town, 1988. http://hdl.handle.net/11427/22132.
Full textA generic, size-based simulation model is developed to investigate the dynamics of carbon and nitrogen flows in plankton communities. All parameters in the model are determined by body size using empirically-determined relationships calculated from published data. The model is robust with respect to most parameters and assumptions. Because the model is based on general ecological principles, it can be used to simulate microplankton community interactions in any planktonic ecosystem. Two coastal ecosystems from the southern Benguela region in South Africa are simulated; one typical of the relatively stable surface waters on the Agulhas Bank and one typical of upwelling plumes, usually found off the west coast of South Africa. Simulated communities compare well with field observations in terms of standing stocks and size composition, and simulation results indicate that the small-scale structure of the two ecosystems and the processes occurring within them are relatively well understood. Consequently, the dynamic functioning of the two systems is investigated at the ecosystem level, using the simulation results. Hypothetical carbon flow networks are constructed, and the average importance of different flow pathways at different times is assessed. In both ecosystems, the vast majority of carbon flows pass through short, efficient-transfer pathways, although longer pathways are potentially possible. Simulation analyses are extended from coastal to oceanic food webs, and the model results are consistent with the hypothesis that oceanic phytoplankton have rapid rates of primary production. At-sea sampling of a phytoplankton bloom is mimicked by "sampling" from simulation output, and interpretation of the data using standard techniques is compared with the model output. The dangers of extrapolating from snapshot measurements is highlighted, and the experiment emphasizes the importance of size-fractionated sampling of phytoplankton. A hypothetical pelagic food web is described, consisting of at least five different trophic pathways from phytoplankton to pelagic fish. It is suggested that coastal waters probably have all the different pathways, and the relative importance and efficiency of the different pathways will determine the total fish production in an ecosystem.
Villacampa, Marion. "Carbon sequestration: mathematical model of the Brazilian Atlantic Forest." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/3/3137/tde-12122016-113919/.
Full textA Mata Atlântica é um dos 34 hotspots mundiais e provavelmente uma das florestas tropicais mais ameaçadas. Entender o sequestro do carbono e construir uma representação válida da dinâmica a longo prazo da floresta é primordial. Restaurar um ecossistema implica conhecer a complexidade dos fenômenos que se desenvolvem nestas formações, compreender os processos que levam à estruturação e manutenção destes ecossistemas ao longo do tempo e, finalmente, utilizar estas informações para a implantação de projetos de restauração. O objetivo desse projeto é buscar conhecimento sobre o crescimento da Mata Atlântica em meio ao comportamento antropogênico extrativista, buscando ações rumo à sustentabilidade e sua importância no processo de sequestro e estocagem de carbono. Desenvolver um modelo de crescimento da floresta adaptado ao local de estudo, que toma em consideração as atividades humanas, nos ajudará a determinar ações rumo à sua sustentabilidade. Na primeira parte da tese, é desenvolvido um modelo matemático que gera um sistema de equações diferenciais ordinárias não lineares. As características do Parque Estadual da Serra do Mar, no estado de São Paulo, são incluídas nesse modelo, que representa várias espécies de árvores agrupadas em nove grupos em função de sua altura máxima e de seu comportamento em relação à sombra. Em seguida, a tese trata do impacto de várias dinâmica da floresta e na estrutura e no sequestro de carbono. Os resultados mostram que o modelo offshore inland minimiza o impacto do desmatamento em termos de quantidade de biomassa perdida ou do impacto na biodiversidade. No final, com o objetivo de restaurar a Mata Atlântica, vários cenários de regeneração são abordados/considerados. O modelo determina em quantos anos a floresta estará restaurada e mostra a importância da contribuição externa de sementes. O desempenho desse modelo traz bons resultados em comparação com outros estudos, e pode ajudar a tomar decisões para a concretização de um futuro sustentável.
Roberts, Chris David. "Numerical modelling of climate and the carbon cycle during the Cenozoic." Thesis, University of Cambridge, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.609403.
Full textLyons, Christopher John. "Development of failure frequency, shelter and escape models for dense phase carbon dioxide pipelines." Thesis, University of Newcastle upon Tyne, 2016. http://hdl.handle.net/10443/3125.
Full textAakenes, Frøydis. "Frictional pressure-drop models for steady-state and transient two-phase flow of carbon dioxide." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for energi- og prosessteknikk, 2012. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-18557.
Full textSun, Yi, and 孙毅. "Path-dependent valuation of generators in the capacity, energy and carbon markets." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2011. http://hub.hku.hk/bib/B45876332.
Full textCordova, Vicente D. "Regional-scale carbon flux estimation using MODIS imagery." Virtual Press, 2005. http://liblink.bsu.edu/uhtbin/catkey/1325989.
Full textDepartment of Natural Resources and Environmental Management
Cox, Barry James. "Mathematical modelling of nano-scaled structures, devices and materials." Access electronically, 2007. http://www.library.uow.edu.au/adt-NWU/public/adt-NWU20080129.102240/index.html.
Full textHart, Rachelle. "Isotopic Evaluation of Carbon Dioxide in Soil Gas in Utah for a More Accurate Input Variable in Groundwater Age Determining Models." BYU ScholarsArchive, 2009. https://scholarsarchive.byu.edu/etd/2248.
Full textNightingale, Joanne M. "Modelling carbon dynamics within tropical rainforest environments using the 3-PG and 3-PGS ecosystem process models /." [St. Lucia, Qld.], 2004. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe18498.pdf.
Full textVieira, José António Breyer Rodrigues. "Valorization of pumpkin residue by supercritical extraction of added-value compounds." Master's thesis, Faculdade de Ciências e Tecnologia, 2014. http://hdl.handle.net/10362/12164.
Full textShih, Shou Hsing. "Forecasting models for economic and environmental applications." [Tampa, Fla] : University of South Florida, 2008. http://purl.fcla.edu/usf/dc/et/SFE0002425.
Full textBackéus, Sofia. "Forest management strategies for CO₂ mitigation." Umeå : Department of Forest Resource Management, Swedish University of Agricultural Sciences, 2009. http://epsilon.slu.se/200989.pdf.
Full textHartikka, Alice, and Simon Nordenhög. "Emission Calculation Model for Vehicle Routing Planning : Estimation of emissions from heavy transports and optimization with carbon dioxide equivalents for a route planning software." Thesis, Linköpings universitet, Energisystem, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-178065.
Full textAiyegbusi, Olufemi. "The Alberta carbon market : an exploration of alternative policy options through agent-based modeling." Thesis, Lethbridge, Alta. : University of Lethbridge, Faculty of Management, c2012, 2012. http://hdl.handle.net/10133/3434.
Full textvii, 155 leaves ; 29 cm
Shafi, Ghufran. "Development of roadway link screening criteria for microscale carbon monoxide and particulate matter conformity analyses through application of classification tree model." Thesis, Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/28222.
Full textCommittee Chair: Guensler, Randall; Committee Member: Rodgers, Michael; Committee Member: Russell, Armistead.
Xu, Yong. "Statistical Models for Environmental and Health Sciences." Scholar Commons, 2011. http://scholarcommons.usf.edu/etd/3414.
Full textHaugsbakk, Frida. "Evaluations of how carbon dioxide calculations can be integrated into 3D models at an early design stage for more efficient Life Cycle Assessments on buildings." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-230168.
Full textLivscykelanalyser på byggnader och olika typer av miljöbyggnads-certifieringar blir allt vanligare för nya byggprojekt i Sverige. Materialet i en byggnad spelar en stor roll av hela byggnadens miljöpåverkan. Tidigare forskning indikerar att livscykelanalyser inte är en rutin i dagens byggprocesser vilket kan bero på att osäkerheter i de olika metoderna bakom koldioxidberäkningar. Den här artikeln fokuserar på hur koldioxidekvivalenter av byggnadsmaterial kan bli integrerade med Byggnadsinformationsmodellering. Genom möten med experter i området har datainsamling gjorts för det ändamålet. För att undersöka integreringen byggdes en 3D-modell upp och som senare användes för beräkningar av koldioxidutsläpp i ett kostnads-kalkyleringsverktyg samt undersöka hur en införing av koldioxidekvivalenter direkt i 3D-modellen kunde göras. Resultaten visade hur kostnads-beräkningsverktyget fungerar för beräkningar av koldioxidekvivalenter, tidigt i byggprocessen. Svårigheter i att hitta motsvarande material i kalkyleringsverktygets databas upptäcktes under utvärderingen samt en sammanfattande rapport för beräkningarna. Integrationen direkt i 3D-modellen med visuell programmering visade att en inmatning av koldioxidutsläpp för varje material fungerade vilket möjliggör uppdateringar under hela byggprocessen. Det var också möjligt att importera materialinformation till ett koldioxidberäkningsverktyg. Det öppnar upp möjligheter att ändra och uppdatera koldioxidutsläpp för material tidigt i byggprocessen med hjälp av Byggnadsinformationsmodellering och visar behov av organisationsförändringar på grund av dagens traditionella byggprocess.
Sigman, Daniel M. "The Role of Biological Production in Pleistocene Atmospheric Carbon Dioxide Variations and the Nitrogen Isotope Dynamics of the Southern Ocean." Ft. Belvoir : Defense Technical Information Center, 1997. http://handle.dtic.mil/100.2/ADA342811.
Full text"September 1997." "Funding was provided by National Science Foundation Grant OCE-9201286, National Science Foundation Graduate Fellowship Program, and the JOI/USSAC Ocean Drilling Graduate Fellowship Program." Includes bibliographical references (p. 152-153).
Hsu, Wei-Ching. "The variability and seasonal cycle of the Southern Ocean carbon flux." Thesis, Georgia Institute of Technology, 2013. http://hdl.handle.net/1853/49079.
Full textLueck, Anthony. "Characterizing two carbonate formations for CO₂-EOR and carbon geosequestration: applicability of existing rock physics models and implications for feasibility of a time lapse monitoring program in the Wellington Oil Field, Sumner County, Kansas." Thesis, Kansas State University, 2016. http://hdl.handle.net/2097/34629.
Full textDepartment of Geology
Abdelmoneam Raef
This study focuses on characterizing subsurface rock formations of the Wellington Field, in Sumner County, Kansas, for both geosequestration of carbon dioxide (CO₂) in the saline Arbuckle formation, and enhanced oil recovery of a depleting Mississippian oil reservoir. Multi-scale data including rock core plug samples, laboratory ultrasonic P-&S-waves, X-ray diffraction, and well log data including sonic and dipole sonic, is integrated in an effort to evaluate existing rock physics models, with the objective of establishing a model that best represents our reservoir and/or saline aquifer rock formations. We estimated compressional and shear wave velocities of rock core plugs for a Mississippian reservoir and Arbuckle saline aquifer, based on first arrival times using a laboratory setup consisting of an Ult 100 Ultrasonic System, a 12-ton hydraulic jack, and a force gauge; the laboratory setup is located in the geophysics lab in Thompson Hall at Kansas State University. The dynamic elastic constants Young’s Modulus, Bulk Modulus, Shear (Rigidity) Modulus and Poisson’s Ratio have been calculated based on the estimated P- and S-wave velocity data. Ultrasonic velocities have been compared to velocities estimated based on sonic and dipole sonic log data from the Wellington 1-32 well. We were unable to create a transformation of compressional wave sonic velocities to shear wave sonic for all wells where compressional wave sonic is available, due to a lack of understandable patterns observed from a relatively limited dataset. Furthermore, saturated elastic moduli and velocities based on sonic and dipole sonic well logs, in addition to dry rock moduli acquired from core plug samples allowed for the testing of various rock physics models. These models predict effects of changing effective (brine + CO₂ +hydrocarbon) fluid composition on seismic properties, and were compared to known values to ensure accuracy, thus revealing implications for feasibility of seismic monitoring in the KGS 1-32 well vicinity.
Knecht, Billberger Magnus F. "Plant growth - stoichiometry and competition : theory development in ecosystem ecology /." Uppsala : Dept. of Ecology and Environmental Research, Swedish University of Agricultural Sciences, 2006. http://epsilon.slu.se/200624.pdf.
Full textRao, Meenakshi. "Investigating the Potential of Land Use Modifications to Mitigate the Respiratory Health Impacts of NO2| A Case Study in the Portland-Vancouver Metropolitan Area." Thesis, Portland State University, 2016. http://pqdtopen.proquest.com/#viewpdf?dispub=10131547.
Full textThe health impacts of urban air pollution are a growing concern in our rapidly urbanizing world. Urban air pollutants show high intra-urban spatial variability linked to urban land use and land cover (LULC). This correlation of air pollutants with LULC is widely recognized; LULC data is an integral input into a wide range of models, especially land use regression models developed by epidemiologists to study the impact of air pollution on human health. Given the demonstrated links between LULC and urban air pollution, and between urban air pollution and health, an interesting question arises: what is the potential of LULC modifications to mitigate the health impacts of urban air pollution?
In this dissertation we assess the potential of LULC modifications to mitigate the health impacts of NO2, a respiratory irritant and strong marker for combustion-related air pollution, in the Portland-Vancouver metropolitan area in northwestern USA. We begin by measuring summer and winter NO2 in the area using a spatially dense network of passive NO 2 samplers. We next develop an annual average model for NO2 based on the observational data, using random forest—for the first time in the realm of urban air pollution—to disentangle the effects of highly correlated LULC variables on ambient NO2 concentrations. We apply this random forest (LURF) model to a 200m spatial grid covering the study area, and use this 200m LURF model to quantify the effect of different urban land use categories on ambient concentrations of NO2. Using the changes in ambient NO2 concentrations resulting from land use modifications as input to BenMAP (a health benefits assessment tool form the US EPA), we assess the NO2-related health impact associated with each land use category and its modifications. We demonstrate how the LURF model can be used to assess the respiratory health benefits of competing land use modifications, including city-wide and local-scale mitigation strategies based on modifying tree canopy and vehicle miles traveled (VMT).
Planting trees is a common land cover modification strategy undertaken by cities to reduce air pollution. Statistical models such as LUR and LURF demonstrate a correlation between tree cover and reduced air pollution, but they cannot demonstrate causation. Hence, we run the atmospheric chemistry and transport model CMAQ to examine to what extent the dry deposition mechanism can explain the reduction of NO2 which statistical models associate with tree canopy.
Results from our research indicate that even though the Portland-Vancouver area is in compliance with the US EPA NO2 standards, ambient concentrations of NO2 still create an annual health burden of at least $40 million USD. Our model suggests that NO2 associated with high intensity development and VMT may be creating an annual health burden of $7 million and $3.3 million USD respectively. Existing tree canopy, on the other hand, is associated with an annual health benefit of $1.4 million USD. LULC modifications can mitigate some fraction of this health burden. A 2% increase in tree canopy across the study area may reduce incidence rates of asthma exacerbation by as much as 7%. We also find that increasing tree canopy is a more effective strategy than reducing VMT in terms of mitigating the health burden of NO 2.
CMAQ indicates that the amount of NO2 removed by dry deposition is an order of magnitude smaller than that predicted by our statistical model. About one-third of the difference can be explained by the lower NO2 values predicted by CMAQ, and one-third may be attributable to parameterization of stomatal uptake.
Venker, Jeanne [Verfasser], and Jörg [Akademischer Betreuer] Starflinger. "Development and validation of models for simulation of supercritical carbon dioxide Brayton cycles and application to self-propelling heat removal systems in boiling water reactors / Jeanne Venker. Betreuer: Jörg Starflinger." Stuttgart : Universitätsbibliothek der Universität Stuttgart, 2015. http://d-nb.info/1074871154/34.
Full textMorand, Hugues. "The economic potential of the Quebec cropping sector to sequester carbon in agricultural soils /." Thesis, McGill University, 2003. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=80335.
Full textResults indicate that carbon sequestration in agricultural soils could only contribute a minor share of the total emission reduction in Quebec, even with very high carbon price levels. At a carbon price of $15/t CO2, it is estimated that changes in tillage practices and permanent cover would result in an additional 12,328 t CO2 per year sequestered by the cropping sector in Quebec. However, some regions display higher adoption rates of carbon sequestering practices than other regions and appear to be more responsive to the price incentive. The introduction of a monetary demand for GHGE offsets from the cropping sector induces some changes in terms of cropping pattern and crop production level, while it has almost no impact on the livestock sector.
Franklin, Oskar. "Plant and forest dynamics in response to nitrogen availability /." Uppsala : Swedish University of Agricultural Sciences, 2003. http://diss-epsilon.slu.se/archive/00000345/.
Full textAppendix consists of reprints of three papers and a manuscript, three of which are co-authored with others. Includes bibliographical references. Also partially issued electronically via World Wide Web in PDF format; online version lacks appendix.
Eriksson, Erik. "The potential for forestry to reduce net CO₂ emissions /." Uppsala : Dept. of Bioenergy, Swedish University of Agricultural Sciences, 2006. http://epsilon.slu.se/2006103.pdf.
Full textFarrell, Troy W. "The mathematical modelling of primary alkaline battery cathodes." Thesis, Queensland University of Technology, 1998.
Find full textGASPAR, Felipe Lima. "Distribuição da alcalinidade total, pressão parcial do CO2 e fluxos de CO2 na interface água-ar no ecossistema costeiro do estado de Pernambuco." Universidade Federal de Pernambuco, 2015. https://repositorio.ufpe.br/handle/123456789/17241.
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A plataforma continental Pernambucana é caracterizada pela oligotrofia e estabilidade térmica ao longo do ano influenciada pela corrente Norte do Brasil, que traz águas quentes e ricas em CO2 para a plataforma continental do nordeste brasileiro. Dentre os principais rios translitorâneos de Pernambuco estão os Rios Capibaribe e Jaboatão que recebem os efluentes domésticos do Recife e região metropolitana, o que causa alterações nos ciclos naturais do carbono. Desta maneira, foram avaliadas a variabilidade da pCO2 nos estuários do Capibaribe e de Barra de Jangadas assim como na plataforma continental interna do Estado de Pernambuco. Para análise nos estuários foram realizadas coletas durante a maré baixa, bimestralmente de Novembro de 2010 a Setembro de 2011. O estuário do Capibaribe apresentou os valores mais elevados de alcalinidade total (AT) e carbono inorgânico total (TCO2), com diferença significativa entre os dois rios. As médias anuais de alcalinidade encontradas foram 1649 ± 390 μmol kg-1 no Capibaribe e 1557±315 μmol kg-1 em Barra de Jangadas. Em relação a pCO2, os estuários apresentaram supersaturação de CO2 em relação a atmosfera durante todo o ano, com médias de 3317 ± 2034 μatm no Capibaribe e 6018 ± 4589 μatm em Barra de Jangadas. Estes valores durante o período chuvoso variaram entre os estuários, com diminuição na pCO2 no Capibaribe e aumentos de até 300% dos valores de pCO2 em Barra de Jangadas. A fim de se obter uma melhor avaliação da distribuição espacial da pCO2 na plataforma interna, foi construído um equipamento para a medição contínua e direta da pCO2 na água como alternativa de baixo-custo em relação aos fabricados importados. A primeira campanha realizada aconteceu em Dezembro de 2014, partindo do porto do Recife em direção ao estuário de Barra de Jangadas. Apesar de o período seco ser o de maior produtividade primária a região apresentou-se oligotrófica, com picos de chl-a (8.4 mg m3) próximo ao Capibaribe. Apenas uma pequena área apresentou subsaturação de CO2 em relação à atmosfera, com o valor mínimo registrado de 376,6 μatm. Foi identificada uma elevada fugacidade de CO2 (fCO2) na área da plataforma interna, com média de 474,33 ± 66,57 μatm, resultando em um fluxo médio para a atmosfera de 8,5 ± 6,82 mmol C m-2d-1. A partir dos resultados obtidos foi proposto um modelo para predizer a fCO2 a partir de valores de salinidade e temperatura para a plataforma interna durante o verão. Uma análise espacial e sazonal mais abrangente dos parâmetros do sistema carbonato na plataforma interna foi realizada utilizando-se dados de AT e TCO2 em áreas com e sem influência de rios entre os anos de 2013 e 2014. As médias da pCO2 e do pH na plataforma interna foram de 449 ± 45 μatm e 8,00 ± 0,03 respectivamente. Os parâmetros analisados foram influenciados pela distância da costa, o que resultou na elaboração de modelos para a predição de AT, TCO2, pCO2, pH, ΩCa e ΩAr a partir de dados de temperatura, salinidade e longitude. A região apresenta elevada alcalinidade inclusive na área influenciada por rios, onde foi encontrada a menor média de AT 2358 ± 28 μmol kg-1. A região apresenta, em curto prazo, baixa vulnerabilidade ao processo de acidificação oceânica. Os valores encontrados de pCO2 e fluxos de CO2 na plataforma continental de Pernambuco estão acima dos estimados nas médias globais para plataformas continentais abertas baseadas em modelos matemáticos. A variabilidade na pCO2 encontrada está ligada à própria característica da água tropical do Atlântico Sul, que cobre a rasa plataforma pernambucana com águas quentes. Onde a baixa solubilidade do CO2 devido à alta temperatura, associada à oligotrofia e aportes de matéria orgânica fazem com que a região da plataforma seja fonte de CO2 para atmosfera durante todo o ano.
The continental shelf of Pernambuco is characterized by oligotrophy and thermal stability throughout the year, influenced by the North Brazil current that brings warm water, rich in CO2 to the continental shelf of northeastern Brazil. The Capibaribe and Jaboatão rivers are one of the major rivers of Pernambuco. They receive a large input of domestic effluents from Recife and its metropolitan area, which causes changes in the natural carbon cycle. Here we evaluated the pCO2 variability in these two estuaries and in the inner shelf area of Pernambuco. To evaluate the role of the estuaries, samples were collected bimonthly during low tide, on a seasonal cycle from November 2010 to September 2011. The Capibaribe estuary presented the highest values of total alkalinity (TA) and total inorganic carbon (TCO2), with a significant difference between the two rivers. Both estuaries showed seasonal variation in TCO2 and TA values. The annual TA averages were 1649 ± 390 μmol kg-1 in the Capibaribe and 1557 ± 315 μmol kg-1 at Barra de Jangadas. Regarding the pCO2, the estuaries were saturated in CO2 throughout the year, with average for the dry season of 3317 ± 2034 μatm in the Capibaribe and 6018 ± 4589 μatm in Barra de Jangadas. These values varied seasonally between estuaries, with a pCO2 decrease during the rainy season in the Capibaribe, and an increase of up to 300% in the Barra de Jangadas estuary. In order to obtain a better evaluation of the spatial distribution of pCO2 over the shelf waters, it was developed an equipment for the continuous and direct measurement of sea surface pCO2 as low-cost alternative to the commercially manufactured ones. The first cruise took place in December 2014, starting from the port of Recife towards the Barra de Jangadas estuary. Even though the dry period has shown the highest primary productivity, the region presented itself as oligotrophic, with peaks of chl-a (8.4 mg m3) under influence of the Capibaribe plume. Only a small area showed CO2 subsaturation to the atmosphere, with the minimum value of 376.6 μatm. In general, a high CO2 fugacity (fCO2) was identified in the entire area of the inner shelf, with average of 474.33 ± 66.57 μatm, resulting in an mean flux to the atmosphere of 8.5 ± 6.82 mmol C m-2 d-1. It was proposed a model to predict the fCO2 using salinity and temperature values for inner the shelf during the summer. A more comprehensive spatial and seasonal distribution of the carbonate parameters was conducted by using values of TA TCO2 in areas subjected and non-subjected to riverine inputs during 2013 and 2014. The area presents a relative stability to what concerns the pCO2 and pH distribution, with overall average values of 449 ± 45 μatm and 8.00 ± 0,03 respectively. In general, the parameters analyzed were influenced by the distance from the coast, resulting in the development of prediction models for TA, TCO2, pCO2, pH, ΩCa and ΩAr using temperature, salinity and longitude data. The area has a low vulnerability to ocean acidification process, the TA is high even in the areas under riverine influence, where the lowest average values was registered 2358 ± 28 μmol kg-1. The values of pCO2 and CO2 fluxes found on the continental shelf of Pernambuco are above those expected on global averages estimated by mathematical models for open continental shelf. The variability in pCO2 found is linked to the own characteristic of the South Atlantic tropical water, which covers the shallow Pernambuco platform with warm waters. The low solubility of CO2 due to high temperature, combined with oligotrophy and the transport of organic matter to be respired outside the estuaries, turns the continental shelf into a source of CO2 to the atmosphere throughout the year.
Vezzoli, Massimiliano. "Intrinsic kinetics of titania photocatalysis : simplified models for their investigation." Thesis, Queensland University of Technology, 2012. https://eprints.qut.edu.au/51574/1/Massimiliano_Vezzoli_Thesis.pdf.
Full textStachiw, Rosalvo. "Modelagem e simulação do processo de adsorção de compostos orgânicos em xisto, catalisador exaurido de FCC e carvão ativado em pó." Universidade Tecnológica Federal do Paraná, 2008. http://repositorio.utfpr.edu.br/jspui/handle/1/135.
Full textThe high cost of the activated carbon has motivated the search of low cost adsorbents such as industrial by-products. In this sense, the use of industrial by-products of oil shale: Oil Shale (XC), Pirolized Oil Shale (XR) and Pirolized Oil Shale with Tires (XRP), from PETROSIX/PETROBRAS, and the spent catalyst (CAT), from FCC (Fluid Catalytic Cracking) unit were characterized and used in this work in the adsorption of organics compounds of industrial liquid effluent. The main contribution of this thesis is to propose a mathematical model to the adsorption process of organic compounds in oil shale, spent catalyst of FCC and powdered activated carbon. This model is based on HSDM (Homogeneous Surface Diffusion Model) model and on the hydraulic behavior of the adsorbent system. Other contribution is the structural and chemical characterization of several samples of oil shale (oil shale, Pirolized oil shale and Pirolized oil shale with Tires) and of the spent catalyst of FCC. A computational model to simulate the adsorption process of these materials is also developed and can be considered an additional contribution of this work. Experimental and simulated results allow characterization of the oil shale adsorbent as basically macroporous and with superficial area about 0.51 to 3.36 m2.g-1. In addition, they present the same crystal structures and clay micrografies characteristics. The adsorbent CAT is composed basically by Faujasite, silica and alumina. They present spherical beads, irregular forms and micropores, with superficial area characteristics of zeolitic materials (148 and 155 m2.g-1). The adsorption tests realized in the synthetic and industrial effluents (Phenolic and Petrochemical) showed the potential of application of the industrial by-products of oil shale and CAT in the removal of organics compounds (dyes, Phenol and COT) of these effluents. In respect of environmental standards to effluents disposal (CONAMA resolution 357), simulations results, obtained with the proposed model, has demonstrated that the use of only oil shale or CAT is not viable, because the high quantity of adsorbents required. However, such adsorbents can be used in the reduction of organic loads in both effluents, when combined with other processes. Each adsorbent showed be used where it is produced because of transportation cost. The CAT is indicated for the treatment of Petrochemical effluent while the others adsorbents may be applied in the phenolic effluent treatment.
Freitas, Ricardo Miguel Costa de. "Desenvolvimento de um modelo experimental de crioablação vertebral em suínos guiada por tomografia computadorizada de feixe cônico." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/5/5151/tde-11012016-124855/.
Full textINTRODUCTION: Percutaneous spine cryosurgery (cryoablation) close to nerves and spinal cord has been performed in the clinical practice, however without experimental studies proving its safety and efficacy. The aim of this work was to develop an experimental swine model of in vivo cone beam computed tomography (CBCT) guided vertebral cryoablation. A preliminary morphometric study of the porcine spine by CBCT imaging was carried out. A specific cryoablation protocol was proposed to adapt the \"ice ball\" to the swine vertebrae dimensions. Subsequently, the protocol was tested in in vitro, ex vivo and in vivo models. METHODS: The institutional animal care committee approved this study. Sixteen anatomical parameters were measured in 36 lumbar swine vertebrae and compared to the same measurements of the CBCT and multidetector CT (MDCT). Three models of in vitro / ex vivo studies were developed for the positioning of thermocouples around the cryoprobe. Isotherms were obtained from measured temperatures for each minute during a 2-8 minutes double freezing-thawing protocol. Twenty -two CBCT-guided vertebral cryoablations were performed in eight pigs. Epidural thermocouples registered the temperatures while carbon dioxide (CO2) was injected in the epidural space to protect nerves. The clinical follow-up was carried out until six days before euthanasia. Clinical and radiologic data were correlated to the histopathology study with light microscopy (n=20) or electron transmission microscopy (n=2). RESULTS: CBCT was proven to be a comparable imaging method to MDCT with significant correlation (p < 0.05) in all variables, except in those including the cartilaginous tissue of the vertebral plateau. The registered isotherms were colder in the ex vivo model embedded in gel (-34 °C and -2 °C; -30 °C and 3 °C; -10 °C and 13 °C, respectively) than in the in vitro model (-23 °C and 3 °C; -7 °C and 10 °C; 1 °C and 16 °C) or the ex vivo model without gel (-30 °C and 28 °C). In the in vivo study the CBCT imaging was well succeeded to demonstrate the cryoprobes inserted in the vertebral body and the epidural CO2 in all procedures. The major complication rate was 4.5%. The distance between the cryoprobe and the spinal canal (Cp-Sc) was the most efficient parameter to categorize the vertebral canal temperatures below 19 °C in the logistic regression model analysis (p < 0.004). Perineural inflammatory infiltrate was not identified in the light microscopy analysis. One swine did not present neurological deficits, although the ultra-structural analysis has evidenced myelin sheath disruption in some large neural fibers. CONCLUSIONS: The CBCT imaging was validated as an imaging method for the swine vertebrae analysis. The ex vivo model embedded in gel featured better the cold preservation in the bone tissue. The combination of a specific freezing protocol associated with epidural protective measures allowed the feasibility of the CBCT-guided vertebral cryoablation in the swine model. The ultra-structural analysis showed early modifications of the nerve fibers
Foster, Laura. "The potential of high resolution palaeoclimate reconstruction from 'Arctica islandica' /." Thesis, St Andrews, 2007. http://hdl.handle.net/10023/411.
Full textZietsman, Johannes Hendrik. "Interactions between freeze lining and slag bath in ilmenite smelting." Thesis, Pretoria : [s.n.], 2004. http://upetd.up.ac.za/thesis/available/etd-11052004-112700.
Full textTitle from opening screen (viewed March 14, 2005). Summaries in English and Afrikaans. Includes bibliographical references.
Pereira, Adriano José. "Gradientes de oxigênio, glicose, dióxido de carbono e lactato em diferentes compartimentos vasculares." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/5/5152/tde-27102011-160323/.
Full textINTRODUCTION: Despite of the widespread use of the central venous oxygen saturation measurement as a therapeutic goal in critically ill patients, absolute differences between this measurement and the mixed venous oxygen exist. Causes of these differences, as well the behavior of these gradients in critical illness, are not completely understood. Considering current therapeutic interventions aimed to reverse tissue oxygenation impairment are mediated by increases in cardiac output; the particular scenario in which the heart is not physiologically able to further increase oxygen extraction and the absence of tools to monitoring the myocardium impact of those interventions, the present study, facing the theoretical possibility of the coronary sinus effluent participation in those central to mixed venous differences, has analyzed the oxygen saturation (SO2), carbon dioxide partial pressure (PCO2), lactate and glucose concentrations behaviors over time, in different models of tissue hypoxia and in different vascular sites. Emphasis on the myocardial energetic metabolism and its impact over central to mixed venous gradients was placed. METHODS: 37 pigs, males, weighting about 35 Kg, sedated and mechanically ventilated, were studied after induction of four different hypoxic injury models (sepsis, and anemic, stagnant, hypoxic hypoxia), eight for group and five controls. In addition to hemodynamic and oxygen variables, SO2, PCO2, lactate and glucose were measured in different phases, in 9 distinct vascular sites, including coronary sinus (femoral artery, inferior and superior vena cava, right atria, right ventricle, pulmonary artery, right suprahepatic vein and portal vein). MAIN RESULTS: Concentrations of O2, lactate and glucose in the coronary sinus effluent presented distinctive patterns among groups: shift from lactate to glucose consumption in hypoxic hypoxia and anemic hypoxia groups, increase in both glucose and lactate consumption in sepsis and absence of clear trend in stagnant hypoxia group. PCO2 gradients from systemic artery to coronary sinus presented late enlargement trend in all groups. In the regional gradients analysis comparisons, coronary sinus presented the lowest SO2, the lowest lactate concentrations, the highest PCO2 levels, and these patterns changed over time. Similar evolution trends were observed between central to mixed venous O2, PCO2, lactate and glucose gradients and the same parameters measured in coronary sinus. CONCLUSIONS: Different concentrations of O2, PCO2, lactate and glucose in coronary sinus are related to the type of hypoxic injury and not only to energetic substrate availability. Severity-related patterns, common to all groups in late phases, were identified: any reduction of coronary SO2, shift to glucose consumption, net lactate myocardial production and equality or inferiority of PCO2 levels related to other vascular compartments (independently of trend). Trends in transmyocardial PCO2 gradients followed cardiac output ones and, certainly, should mirror coronary blood flow. Regional gradients analysis showed suitable to explore specific regional metabolic settings, as in the described example of liver metabolism, in which production of glucose were maintained in all phases by this organ in hypoxic hypoxia groups, differently from the impaired production described in literature for sepsis. At last, data from sepsis group have showed: a) as to the previously known central to mixed venous SO2 and lactate gradients, PCO2 and glucose gradients also exist; b) coronary sinus has participated significantly in formation of central to mixed venous lactate, PCO2 and glucose gradients
Brown, Steven Richard. "A design of experiments approach for engineering carbon metabolism in the yeast Saccharomyces cerevisiae." Thesis, University of Exeter, 2016. http://hdl.handle.net/10871/26158.
Full textEl, Hassan Jinane. "Evaluation fiabiliste de l'impact des facteurs climatiques sur la corrosion des poutres en béton armé : application au cas libanais." Thesis, Clermont-Ferrand 2, 2010. http://www.theses.fr/2010CLF22064/document.
Full textWhen exposed to aggressive environment, reinforced concrete structures are subject to a degradation mechanism that affects their integrity. Among various environmental attacks, the corrosion of RC structures is considered the most dangerous. The process is launched by the penetration of aggressive agents, precisely the chlorides and carbon dioxide into the concrete. The chlorides induce a localized corrosion, also called pitting corrosion, while on the other hand the carbon dioxide leads to a general corrosion called uniform corrosion. This corrosion phenomenon depends on several factors such as the materials characteristics,loadings, geometry and the environment. All these components include different levels of uncertainties that are taken into account throughout a probabilistic approach. In this work, we propose two models for the corrosion mechanisms induced separately by the chlorides and the carbon dioxide. These models take into account the effect of the climatic condition that is mainly described by the temperature and the relative humidity. In addition to that, as a study case we have treated in details the Lebanese climatic context. We have proposed a physical model of steel corrosion in reinforced concrete beams that occurs in two phases : - An initiation phase where aggressive agents like the chlorides and carbon dioxide penetrate into the concrete and reach a critical concentration values causing the depassivation of the steel ; - A propagation phase in which the active corrosion of steel decreases the strength of the beam leading to its failure. All the factors that have uncertainties are treated as random variables. Several probabilistic models are listed and discussed in the literature while only the models that match with our context are selected. The reliability analysis allowed us to assess the reliability of beams subjected to corrosion in ULS and SLS. The loss of steel section due to the corrosion mechanism induces a decrease of the bearing beam capacity, and an increase in the tension stress in the concrete.This causes an increase of the width of cracks openings. Thus, taking into account the serviceability limit state, the safety margin goes to zero when the width of crack opening exceeds the acceptable width as recommended by the Eurocode 2. The limit state function in ULS is the bending strength. The failure occurs when the applied moment equals or surpasses the resisting moment. The reliability calculations are carried out using Monte-Carlo simulations. Finally, several applications to the corrosion model are proposed via this work. The first application concerns the sensitivity analysis of the corrosion models for the different parameters. The effects of the mean values and the variability of the random variables on the model response are also examined. The impact of climatic factors on the corrosion phenomenon took the biggest part of this work. We have applied the chloride’s corrosion model with the real temperatures and relative humidity of three coastal cities having different climatic characteristics. Then a comparative study showing the effect of the ba rdiameters and the cover thickness on the reliability of the RC beam subjected to aggressive environment is carried out. (...)