Estimativas sobre alterações climáticas globais têm aumentando a demanda por estudos sobre propriedades dos solos relativamente secos e limitações impostas à absorção de água pelas plantas em condições de escassez hídrica. Neste estudo, fatores que influenciam a retenção da água no solo e o murchamento de plantas foram avaliados com base no conceito de equilíbrio da água no solo. Objetivou-se com este estudo: (i) avaliar a confiabilidade de medições do conteúdo de água no solo sob altas sucções matriciais em câmaras de pressão, usando como referência a técnica de ponto de orvalho (ii) avaliar as interações entre espécies de plantas e solos com diferentes classes texturais no ponto de murcha permanente (iii) investigar as relações entre equilíbrio hidráulico da água no solo e murchamento de plantas a partir do conceito de corte hidráulico. Para tanto, um experimento para avaliar a influência dos tipos de solos e espécies de plantas, no ponto de murcha permanente foi conduzido em casa de vegetação da Escola Superior de Agricultura \"Luiz de Queiroz\" da Universidade de São Paulo, Piracicaba, São Paulo. Avaliou-se o murchamento de plantas de girassol (Helianthus annuus L.), milho (Zea mays L.) e soja (Glycine max L.). Os solos utilizados no estudo foram coletados na camada superficial (0-10 cm) em quatro áreas, selecionadas com o objetivo de obter classes texturais contrastantes, localizadas no município de Piracicaba, São Paulo, Brasil. Sub-amostras foram utilizadas para determinação da distribuição do tamanho de partículas e atributos químicos. Amostras indeformadas foram coletadas para a determinação da curva de retenção da água no solo pela técnica de câmaras de pressão. Adicionalmente, amostras deformadas foram utilizadas para determinação das características de retenção da água no solo pela técnica do ponto de orvalho em altos valores de sucções matriciais. Os dados de retenção de água no solo foram ajustados a modelos empíricos para estimativas da sucção matricial e conteúdo de água relacionada à água em equilíbrio hidráulico (água residual). Foram observadas similaridades nas determinações das características de retenção da água no solo entre as técnicas de câmaras de pressão e ponto de orvalho, sugerindo a boa drenagem das amostras de solo em câmaras de pressão. Interações significativas foram observadas entre os tipos de solos e espécies de plantas no ponto de murcha permanente, indicando que o movimento de água no contínuo solo-planta-atmosfera foi dependente de resistências relacionadas tanto ao solo quanto às plantas. Ou seja, tanto à capacidade do solo em transportar água até raízes, quanto à habilidade das plantas em absorver a água transportada, assim como, aos processos de regulação de água que ocorrem nas plantas. A abordagem baseada no conteúdo de água residual para o intervalo de sucções matriciais de 0 a 15.000 hPa não foi adequada para ilustrar a condição de equilíbrio hidráulico da água no solo, definidos pelo corte hidráulico, e relações com as sucções matriciais em ocorre o murchamento de plantas. / Estimates about climate changes have increased the demand for studies of the properties of relatively dry soil and limitations on the plants water uptake in conditions of water scarcity. In this study, factors influencing the soil water retention and wilting plants were evaluated based on the concept of soil water equilibrium. The objectives of this study were: (i) to evaluate the reliability measurements of the soil water retention on pressure plate apparatus at high matric suctions using as reference the dew point meter (ii) to evaluate the interactions between soil types and plant species at permanent wilting point (iii) investigate the relationship between the hydraulic equilibrium of soil water and the plant wilting based on the hydraulic cut-off concept. A pot experiment to evaluate the effect of plant and soil types at permanent wilting point was carried out in a greenhouse at the Agricultural\'s College \"Luiz de Queiroz\" from University of São Paulo in Piracicaba, São Paulo, Brazil. Soil samples were collected at the topsoil (0-10 cm) from four different locations around the city of Piracicaba, São Paulo, Brazil. Subsamples were taken to determine the particle size distribution and chemical analysis. To determine soil water retention curve 30 soil samples were collected with undisturbed soil cores. The soils were selected to have a range of texture and organic carbon content. The wilting was evaluated using plants of sunflower (Helianthus annuus L.), maize (Zea mays L.) and soybean (Glycine max L.). The soil water retention data were fitted to the empirical models for estimating the matric suction and water content related soil water at hydraulic equilibrium (residual water content). Similar soil water content were observed for measurements at pressure plate apparatus and dew point meter, suggesting good drainage of the soil samples in pressure plate apparatus for the dry range of soil water retention curve. Significant interactions were observed between soil types and plant species at permanent wilting point, indicating that the water movement in the soil-plant-atmosphere continuum was dependent of resistances related to soil and the plants properties. The approach based on the residual water content for the matric suctions from 0 to 15,000 hPa was not adequate to illustrate the hydraulic equilibrium of the soil water defined by the cut-hydraulic and relations with the matric suction at wilting plants.

Estimativas sobre alterações climáticas globais têm aumentando a demanda por estudos sobre propriedades dos solos relativamente secos e limitações impostas à absorção de água pelas plantas em condições de escassez hídrica. Neste estudo, fatores que influenciam a retenção da água no solo e o murchamento de plantas foram avaliados com base no conceito de equilíbrio da água no solo. Objetivou-se com este estudo: (i) avaliar a confiabilidade de medições do conteúdo de água no solo sob altas sucções matriciais em câmaras de pressão, usando como referência a técnica de ponto de orvalho (ii) avaliar as interações entre espécies de plantas e solos com diferentes classes texturais no ponto de murcha permanente (iii) investigar as relações entre equilíbrio hidráulico da água no solo e murchamento de plantas a partir do conceito de corte hidráulico. Para tanto, um experimento para avaliar a influência dos tipos de solos e espécies de plantas, no ponto de murcha permanente foi conduzido em casa de vegetação da Escola Superior de Agricultura \"Luiz de Queiroz\" da Universidade de São Paulo, Piracicaba, São Paulo. Avaliou-se o murchamento de plantas de girassol (Helianthus annuus L.), milho (Zea mays L.) e soja (Glycine max L.). Os solos utilizados no estudo foram coletados na camada superficial (0-10 cm) em quatro áreas, selecionadas com o objetivo de obter classes texturais contrastantes, localizadas no município de Piracicaba, São Paulo, Brasil. Sub-amostras foram utilizadas para determinação da distribuição do tamanho de partículas e atributos químicos. Amostras indeformadas foram coletadas para a determinação da curva de retenção da água no solo pela técnica de câmaras de pressão. Adicionalmente, amostras deformadas foram utilizadas para determinação das características de retenção da água no solo pela técnica do ponto de orvalho em altos valores de sucções matriciais. Os dados de retenção de água no solo foram ajustados a modelos empíricos para estimativas da sucção matricial e conteúdo de água relacionada à água em equilíbrio hidráulico (água residual). Foram observadas similaridades nas determinações das características de retenção da água no solo entre as técnicas de câmaras de pressão e ponto de orvalho, sugerindo a boa drenagem das amostras de solo em câmaras de pressão. Interações significativas foram observadas entre os tipos de solos e espécies de plantas no ponto de murcha permanente, indicando que o movimento de água no contínuo solo-planta-atmosfera foi dependente de resistências relacionadas tanto ao solo quanto às plantas. Ou seja, tanto à capacidade do solo em transportar água até raízes, quanto à habilidade das plantas em absorver a água transportada, assim como, aos processos de regulação de água que ocorrem nas plantas. A abordagem baseada no conteúdo de água residual para o intervalo de sucções matriciais de 0 a 15.000 hPa não foi adequada para ilustrar a condição de equilíbrio hidráulico da água no solo, definidos pelo corte hidráulico, e relações com as sucções matriciais em ocorre o murchamento de plantas. / Estimates about climate changes have increased the demand for studies of the properties of relatively dry soil and limitations on the plants water uptake in conditions of water scarcity. In this study, factors influencing the soil water retention and wilting plants were evaluated based on the concept of soil water equilibrium. The objectives of this study were: (i) to evaluate the reliability measurements of the soil water retention on pressure plate apparatus at high matric suctions using as reference the dew point meter (ii) to evaluate the interactions between soil types and plant species at permanent wilting point (iii) investigate the relationship between the hydraulic equilibrium of soil water and the plant wilting based on the hydraulic cut-off concept. A pot experiment to evaluate the effect of plant and soil types at permanent wilting point was carried out in a greenhouse at the Agricultural\'s College \"Luiz de Queiroz\" from University of São Paulo in Piracicaba, São Paulo, Brazil. Soil samples were collected at the topsoil (0-10 cm) from four different locations around the city of Piracicaba, São Paulo, Brazil. Subsamples were taken to determine the particle size distribution and chemical analysis. To determine soil water retention curve 30 soil samples were collected with undisturbed soil cores. The soils were selected to have a range of texture and organic carbon content. The wilting was evaluated using plants of sunflower (Helianthus annuus L.), maize (Zea mays L.) and soybean (Glycine max L.). The soil water retention data were fitted to the empirical models for estimating the matric suction and water content related soil water at hydraulic equilibrium (residual water content). Similar soil water content were observed for measurements at pressure plate apparatus and dew point meter, suggesting good drainage of the soil samples in pressure plate apparatus for the dry range of soil water retention curve. Significant interactions were observed between soil types and plant species at permanent wilting point, indicating that the water movement in the soil-plant-atmosphere continuum was dependent of resistances related to soil and the plants properties. The approach based on the residual water content for the matric suctions from 0 to 15,000 hPa was not adequate to illustrate the hydraulic equilibrium of the soil water defined by the cut-hydraulic and relations with the matric suction at wilting plants.

This master's thesis deals with the design of stoker-fired boiler for combustion of biomass. The main points of work are stoichiometry calculation of combustion, determining the dew point of flue gas, calculation of losses, which ones serves for determination of boiler efficiency, dimension design and detail calculation of thermosetting surfaces. In the last chapter is numbered total balance and real thermal efficiency of boiler.

Der Kaltstart von Polymerelektrolytmembran Brennstoffzellen (PEM-BZ) stellt nach wie vor eine wesentliche Herausforderung dar. Passende Betriebsstrategien sind für Start und Shutdown von entscheidender Bedeutung um den BZ-Stack nicht irreversibel zu schädigen. Vor allem das geeignete Wassermanagement muss in den Fokus gerückt werden, da gefrierendes Reaktionswasser sowohl beim Start als auch bei der Lagerung unter Frostbedingungen die Funktionstüchtigkeit der PEMBZ beeinträchtigen können. Im Rahmen des Forschungsprojektes HZwo: InTherm wurde von der Professur Alternative Fahrzeugantriebe ein Teststand für die Untersuchung von Shutdownprozeduren und Froststarts entwickelt. Für die Feuchtemessung wurde ein Taupunkthygrometer verwendet und um die Vorgänge im Stack nachzuvollziehen drei Stromdichte- Temperaturverteilungsmessungen integriert.

Made available in DSpace on 2014-12-17T15:01:27Z (GMT). No. of bitstreams: 1 SidrakJP_DISSERT.pdf: 3365381 bytes, checksum: 55b6f324d82bc4f385aa87921831ed44 (MD5) Previous issue date: 2011-12-20 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / This dissertation aims to assess the representativeness of the manual chilled mirror analyzer (model II Chanscope 13-1200-CN-2) used for the determination of condensed hydrocarbons of natural gas compared to the indirect methods, based on thermodynamic models equation of state. Additionally, it has been implemented in this study a model for calculating the dew point of natural gas. The proposed model is a modification of the equation of state of Peng-Robinson admits that the groups contribution as a strategy to calculate the binary interaction parameters kij (T) temperature dependence. Experimental data of the work of Brown et al. (2007) were used to compare the responses of the dew point of natural gas with thermodynamic models contained in the UniSim process simulator and the methodology implemented in this study. Then two natural gas compositions were studied, the first being a standard gas mixture gravimetrically synthesized and, second, a mixture of processed natural gas. These experimental data were also compared with the results presented by UniSim process simulator and the thermodynamic model implemented. However, data from the manual analysis results indicated significant differences in temperature, these differences were attributed to the formation of dew point of water, as we observed the appearance of moisture on the mirror surface cooling equipment / O presente trabalho de disserta??o tem por objetivo avaliar a representatividade do analisador manual de espelho refrigerado (Chanscope II modelo 13-1200-C-N-2) usado para a determina??o do condensado de hidrocarbonetos de g?s natural frente aos m?todos indiretos, fundamentados em modelos termodin?micos de equa??o de estado. Adicionalmente, tem sido implementado neste estudo um modelo para c?lculo do ponto de orvalho de g?s natural. O modelo proposto constitui uma modifica??o na equa??o de estado de Peng-Robinson que admite a contribui??o de grupos como estrat?gia para calcular os par?metros de intera??o bin?ria kij(T) com depend?ncia da temperatura. Dados experimentais do trabalho de Brown et al. (2007) foram utilizados para comparar as respostas de ponto de orvalho do g?s natural com os modelos termodin?micos contidos no simulador de processo UniSim e com a metodologia implementada neste estudo. Em seguida, duas composi??es de g?s natural foram estudadas, sendo a primeira uma mistura padr?o de g?s sintetizada gravimetricamente e, a segunda, uma mistura de g?s natural processado. Tais dados experimentais foram tamb?m comparados com os resultados apresentados pelo simulador de processo UniSim e pelo modelo termodin?mico implementado. No entanto, os dados do analisador manual indicaram diferen?as significativas nos resultados de temperaturas, sendo estas diferen?as atribu?das ? forma??o de ponto de orvalho de ?gua, j? que foi observado o aparecimento de umidade sobre a superf?cie do espelho refrigerado do equipamento

Tato práce je zaměřena na systém vodního vstřikování a způsoby zajištění dostatečného množství potřebné kapaliny pro správný chod tohoto systému. Jedním zajímavým a nezávislým řešením je využití odpadních produktů motoru, a to vodní páry produkované spalováním paliva. Pro zajištění kondenzace je nutné zchlazení výfukových plynů pod rosný bod páry, což lze zajistit opatřením výfukového potrubí chladiči. Vzniklý kondenzát je pak potřeba efektivně oddělit od proudu plynů a zachytit. Návrh takovéhoto systému vychází z reálně naměřených dat a jeho následným ověřením pomocí CFD simulace.

To meet the continuously rising demand for natural resources and high-value compounds, the development of new and more efficient separation technologies is important from both an economic and environmental point of view. Moreover, the detailed knowledge of adsorption phenomena can be beneficial for the development of task-specific adsorbents for gas separation processes. However, new or supplementary measurement techniques are needed to broaden the understanding of the underlying molecular mechanisms and to characterize promising materials with a fast and reliable method. Raman spectroscopy holds the potential to advance the state-of-the-art in thermophysical property research for CCS technologies in multiple ways. It can not only be utilized for fundamental research on adsorption on quasi non-porous materials due to the possibility to monitor the composition of fluid mixtures but also for the characterization of newly developed porous adsorbents. In this context, Raman spectroscopy was explored in this work to characterize the sorption capacity of translucent porous materials and to investigate the underlying mechanisms that govern sorption processes.:1 Introduction 2 Motivation 3 Experimental Background 4 Adsorption on Quasi Non-Porous Materials 5 Adsorption on Translucent Porous Materials 6 Gas Solubility in Liquids 7 Conclusion and Outlook 8 References Appendix: A Determined Peak Intensities for Adsorption Measurements B Determined Peak Intensities for Solubility Measurements C Results for Absorption Measurements D Results for Solubility Measurements E Propagation of Error / Um den ständig steigenden Bedarf an natürlichen Ressourcen und hochwertigen Verbindungen zu decken, ist die Entwicklung neuer und effizienterer Trenntechnologien sowohl aus wirtschaftlicher als auch aus ökologischer Sicht wichtig. Darüber hinaus kann die detaillierte Kenntnis von Adsorptionsphänomenen für die Entwicklung aufgabenspezifischer Adsorbentien für Gastrennverfahren von Nutzen sein. Es werden jedoch neue oder ergänzende Messverfahren benötigt, um das Verständnis der zugrunde liegenden molekularen Mechanismen zu erweitern und vielversprechende Materialien mit einer schnellen und zuverlässigen Methode zu charakterisieren. Die Raman Spektroskopie hat das Potenzial, den aktuellen Stand der Technik bei der Erforschung thermophysikalischer Eigenschaften für CCS-Technologien in mehrfacher Hinsicht zu verbessern. Sie kann nicht nur für die Grundlagenforschung zur Adsorption an quasi nicht-porösen Materialien genutzt werden, da mit ihr Zusammensetzung von Fluidgemischen bestimmt werden kann, sondern auch für die Charakterisierung neu entwickelter poröser Adsorptionsmittel. In diesem Kontext wurde die Raman-Spektroskopie in dieser Arbeit eingesetzt, um die Sorptionskapazität von transluzenten porösen Materialien zu charakterisieren und die zugrundeliegenden Mechanismen zu untersuchen, welche die Sorptionsprozesse steuern.:1 Introduction 2 Motivation 3 Experimental Background 4 Adsorption on Quasi Non-Porous Materials 5 Adsorption on Translucent Porous Materials 6 Gas Solubility in Liquids 7 Conclusion and Outlook 8 References Appendix: A Determined Peak Intensities for Adsorption Measurements B Determined Peak Intensities for Solubility Measurements C Results for Absorption Measurements D Results for Solubility Measurements E Propagation of Error

Contexte : La dengue est une fièvre ayant pris davantage d’ampleur dans plusieurs régions du monde à climat tropical, dont le département Méta en Colombie, un lieu endémique dans la dernière décennie. Sachant que la propagation de cette maladie est entièrement dépendante des sites de reproduction du vecteur de transmission Aedes, l’investigation de prédicteurs environnementaux les affectant nous semblait pertinente d’un point de vue épidémiologique. Notre étude vise des retombées sur un plan de surveillance de santé publique et l’élaboration de programmes basés sur des observations temporelles et spatiales. Objectifs : Décrire la distribution spatio-temporelle de la dengue dans les 29 municipalités de Méta selon des prédicteurs environnementaux, soit les précipitations, la température ambiante, la température du point de rosée et la pression au niveau de la mer dans le cadre d’une étude écologique. Méthodes : Des données de surveillance SIVIGILA, de télédétection ainsi que de recensement DANE des 29 municipalités du département de Méta entre 2011 et 2019 ont été utilisées pour étudier l’association entre la dengue et les prédicteurs environnementaux. La modélisation de ces associations a été effectuée à l’aide d’un modèle de Markov cachés à changement de régime. Résultats : Des associations positives importantes ont été détectées entre les précipitations et l’incidence de la dengue atteignant des risques relatifs élevés (RR=1.97 à El Calvario à un décalage de 5 semaines ; RR=1.61 à San Juanito à un décalage de 20 semaines). La température ambiante et la température du point de rosée ont suivi en matière de pertinence n’excédant pas des RR de 1.11 pour la maladie. Or, la pression au niveau de la mer n’a pas présenté des résultats concluants. Selon les différents aspects étudiés dans les nombreuses cartes de ce mémoire, nous avons observé une dépendance géographique répétée à l’ouest du département. Conclusion : Nos conclusions recommandent qu’une attention particulière de la santé publique doit s’imposer quant à la prévention de la dengue en saison pluvieuse dans le Meta. Les hausses des valeurs de température ambiante et de la température du point de rosée peuvent expliquer certaines augmentations de l’incidence et incitent donc à la surveillance de ces paramètres également. À noter que nos résultats ont possiblement pu être influencés par un biais d’information et un biais de confusion. / Context: Dengue is a type of fever that has significantly spread in several regions of the world characterized by a tropical climate, including the Meta department in Colombia, which seemed to be an endemic place in the last decade. Knowing that the spread of this disease is entirely dependent on the reproduction sites of the Aedes transmission vector, the study of environmental predictors affecting those sites seemed relevant from an epidemiological point of view. Our study aims to add to the knowledge that can be used for public health surveillance and program elaboration based on temporal and spatial observations of dengue patterns within the region. Objectives: To describe the spatiotemporal distribution of dengue fever in the 29 municipalities of Meta according to its environmental predictors (i.e. precipitation, ambient temperature, dew point temperature and pressure at sea level) within the framework of an ecological study. Methods: SIVIGILA surveillance, remote sensing and DANE census data from 29 municipalities in the Meta department between 2011 and 2019 were used to study the association between dengue fever and environmental predictors. These associations were modeled using a regime-switching hidden Markov model. Results: Significant positive associations were detected between rainfall and dengue incidence reaching high relative risks (RR=1.97 in El Calvario at a 5-week lag; RR=1.61 in San Juanito at a 20-week lag). Ambient temperature and dew point temperature followed in terms of relevance not exceeding RRs of 1.11 for disease. However, pressure at sea level did not show conclusive results. According to the different aspects studied in the many geographical maps of this thesis, we observed a repeated geographical dependence in the west of the department. Conclusion: We recommend that special public health attention should be given to the prevention of dengue fever in the rainy season in Meta. Increases in ambient temperature values and dew point temperature may explain some increases in incidence and therefore prompt monitoring of these parameters as well. It should be noted that our results may have been influenced by an information bias and confusion bias.

NOx sensors have become salient components in the development of efficient exhaust after treatment system for heavy duty vehicles in the past few years. When the accumulated water inside the silencer splashes on to the NOx sensor, it can cause permanent cracks in the sensor. To protect the sensor from this mode of failure, a dew point strategy is developed at Scania. This is important to predict when it is safe to switch on the NOx sensor without causing any harm to it. But the strategy currently includes only the phase transfer phenomena and neglects the effect of the water blow out phenomena inside the silencer. To investigate the effect of water blow out, an experimental test method is designed and the experiments are conducted at different locations in the silencer. The results from the experiments shows that the effect of water blow out is certainly an important factor to develop a better dew point strategy model. For a selected location, the quantity of water remaining after blow out and the time taken for the blow out phase are collected as data from the experiments. A mathematical model for the water blow out phenomena is developed in MATLAB. The model estimates the maximum amount of water which could be present in all the subvolumes of the silencer considering the effect of water blow out. The model is verified with the experimental data for a Scania CAS1 silencer. Calibration guidelines for the developed blow out model are also documented in this report. / NOx sensorer har blivit viktiga komponenter i utvecklingen av ett effektivt avgassystem för tunga fordon under de senaste åren. När det ackumulerade vattnet i ljuddämparen stänker på NOx-sensorn kan det orsaka permanenta sprickor i sensorn. För att skydda sensorn från detta misslyckande utvecklas en daggpunktsstrategi på Scania. Detta är viktigt att förutsäga när det är säkert att slå på NOx-sensorn utan att skada den. Men strategin innehåller för närvarande endast fasöverföringsfenomenen och försummar effekten av att vatten blåser ut fenomen inuti ljuddämparen. För att undersöka effekten av utblåsning av vatten utformas en experimentell testmetod och experimenten utförs på olika platser i ljuddämparen. Resultaten från experimenten visar att effekten av vattenblåsning verkligen är en viktig faktor för att utveckla en bättre daggpunktsstrategimodell. För en vald plats samlas mängden vatten kvar efter utblåsning och den tid det tar för utblåsningsfasen som data från experimenten. En matematisk modell för fenomen för vattenblåsning utvecklas i MATLAB. Modellen uppskattar den maximala mängden vatten som kan finnas i ljuddämparens undervolymer med tanke på effekten av vatten som blåser ut. Modellen verifieras med experimentdata för en Scania CAS1 ljuddämpare. Kalibreringsriktlinjer för den utvecklade utblåsningsmodellen dokumenteras också i denna rapport.

This diploma thesis solves the problems of hydrothermal processes in walls of wooden houses and associated issues. A chosen were two apartment buildings, where they underwent exmerimental measurement of indor air, in order to determine the boundary conditions commonly boundary building evelope. Was followed by hygrothermal analysis of four commonly used constructions of wooden buildings in the Czech Republic, using various numerical methods. The quantity of information obtained from various numerical methods were analyzed individually. The final part of the thesis is devoted to experimental measurements of diffusion properties of materials. Namely foil vapor barrier, in terms of its influence on the perforation vapor diffusion resistance factor. Information obtained from the experiments were applied to re numerical analysis for walls with a foil vapor barrier. Followed by comparing both cases, in terms of changes hygrothermal behavior of structures with influence of perforation of the vapor barrier.