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Avaliação de um sistema de resfriamento passivo para o clima de Curitiba / Evaluation of an indirect passive cooling system under Curitiba climateLange, Sérgio Costa 31 May 2016 (has links)
O Resfriamento Evaporativo Direto (RED), baseado na aspersão de água sob a forma de gotículas no interior dos ambientes; e o Resfriamento Evaporativo Indireto (REI), caracterizado pela umidificação de coberturas e por produzir resfriamento sem aumentar a umidade relativa do interior da edificação, são estratégias de projeto bioclimático ainda relativamente pouco usadas no Brasil. O presente estudo tem por objetivo avaliar a aplicação de uma forma particular de REI (que alia o resfriamento evaporativo à inércia térmica propiciada por um reservatório d’água) para o condicionamento térmico de ambientes em situação de calor na cidade de Curitiba. Foram confeccionadas, monitoradas e comparadas inicialmente duas células-teste em escala reduzida: um Módulo de Controle (MC) e um Módulo Experimental (ME), sendo que o ME foi dotado de uma cobertura estanque constituída de um reservatório d’água sujeita à evaporação. Uma segunda configuração de ME também foi testada em um período de monitoramento subsequente, o que possibilitou comparar-se o efeito do resfriamento evaporativo com o uso isolado do sistema sem uso do REI, em situação apenas de aumento da massa térmica. Uma terceira configuração de ME buscou combinar o aumento da massa térmica aliado ao efeito do resfriamento evaporativo. Resultados apontam para a vantagem do uso do REI para o resfriamento interno das células- teste com: redução de 2,5°C da temperatura média e de 8,0°C de redução da temperatura máxima em relação ao caso base. Também foi verificado uma forte relação entre a temperatura interna devido ao resfriamento evaporativo e a depressão da temperatura de bulbo úmido. / Direct evaporative cooling systems (DECS) based on sprinkling water indoors in the form of droplets and indirect evaporative cooling systems (IECS), characterized by the use of wetted roof or wall surfaces for cooling without increasing the indoor air moisture, consist of interesting bioclimatic strategies still not quite explored in Brazil. This study aims to evaluate the use of a particular form of IECS (which combines evaporative cooling and thermal mass brought about by a water reservoir) for indoor thermal control in warm conditions in Curitiba, Two test cells were initially built, monitored and compared to each other: a control module (CM) and an experimental module (EM), the latter provided with an evaporative pond. A subsequent configuration of the system which cancels out the evaporative function of the system and that is solely based on the increase of thermal mass, was tested in a second monitoring round. A third configuration of EM combinig evaporative cooling and the increase of termal mass was tested. Results showed a higher effectiveness of the IECS for the indoor cooling of the tested cells. The average temperature in EM was reduced in 2.5°C and the maximum temperature was reduced in 8.0°C in comparison with the CM. Results also showed a strong relation between the wet-bulb temperature depression and the internal temperature decrease achieved by the evaporative cooling strategy.
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Fenóis totais no cafeeiro em razão das fases de frutificação e do clima. / Total phenols in the coffee tree due to the fructification phases and the climate.Paula Rodrigues Salgado 14 January 2005 (has links)
Os vegetais apresentam defesa natural contra os fatores externos, bióticos e abióticos, por meio da síntese de compostos fenólicos no metabolismo secundário, as quais variam com as fases fenológicas e com o clima. O aumento dos compostos fenólicos nas plantas está, diretamente, relacionado com a resistência à infecção por patógenos e à infestação de pragas. Entretanto, pouco se sabe sobre a variação dos teores dessa substância durante os estádios fenológicos do cafeeiro, em particular, nas fases de frutificação, e em razão das condições climáticas. Tais conhecimentos são fundamentais para a previsão dos riscos de ataques aos vegetais, uma vez que a defesa natural da planta deve mudar ao longo do ciclo. O experimento foi realizado em uma cultura de Coffea arabica L., cultivar Obatã IAC 1669-20, instalada no campo experimental do Departamento de Produção Vegetal, da Escola Superior de Agricultura Luiz de Queiroz, Universidade de São Paulo, Piracicaba/SP. Para a realização do experimento foi adotado o delineamento experimental inteiramente casualizado, utilizando quatro tratamentos (plantas com e sem frutos - folhas dreno e plantas com e sem frutos - folhas fonte) e cinco repetições constituídas por plantas individuais. Após a análise de variância dos resultados foi aplicado o teste t de Student ao nível de 5 % de significância para a comparação das médias entre os tratamentos. Os teores de fenóis totais (µg g-1) foram extraídos das folhas maduras (fonte) e novas (dreno) e analisados em relação à produção de café, fenologia e clima. As variáveis climáticas adotadas foram temperatura atmosférica (média, mínima e máxima; oC), radiação global (MJ m-2 dia-1) e insolação diária (h dia-1). Durante a condução do experimento foram realizadas avaliações de altura da planta (cm), diâmetro do caule (mm) e comprimento de ramos plagiotrópicos (cm) para determinar as respectivas taxas de crescimento vegetativo das plantas. As quantidades de fenóis totais determinadas nas plantas com produção (17.40 µg g-1 e 13.89 µg g-1 folhas dreno e fonte, respectivamente) e sem produção de café (18.65 µg g-1 e 12.76 µg g-1 folhas dreno e fonte, nessa ordem) não variaram. No entanto, a concentração de fenóis totais nas folhas novas (dreno) das plantas com e sem produção de café foi maior que a quantidade determinada nas folhas maduras (fonte), da ordem de 25 % e 46 %, respectivamente. A síntese de fenóis nas fases de expansão (16.35 µg g-1) e granação dos frutos (14.68 µg g-1) foi 31 % inferior em relação às quantidades determinadas na fase de maior produção dessas substâncias fruto em maturação (21.24 µg g-1). A metabolização de fenóis totais depende, indiretamente, da temperatura (oC) e da radiação global (MJ m-2 dia-1), apresentando tendência inversa em relação a estas variáveis climáticas. A orientação do manejo fitossanitário deve levar em consideração as épocas em que há comprometimento da defesa natural da planta, em relação à produção de substâncias protetivas os fenóis. / The vegetables show a natural defense against external factors, biotic and abiotic, by the synthesis of the phenolic compounds in the secondary metabolism, which varies with the maturity state and with the climate. The increase of phenolic compounds in the plants is directly related to the resistance to the infection thought pathogens and insect infestation. However, little is known about the variation in the content of this substance during the maturity state of the coffee tree, particularly in the fructification phases due to the climatic variations. Such knowledge is the base for the risks analyses of attacks to vegetables, since the natural defense of the plant shall change during the cycle. The experiment was carried out in a Coffea arabica L. crop, to cultivar Obatã IAC 1669-20, installed in the experimental field of the department of vegetal production of the Escola Superior de Agricultura "Luiz de Queiroz", University of São Paulo, Piracicaba/SP. For the accomplishment of the experiment it was adopted a totally randomized experimental design, using four treatments (plants with and without fruits drain leaves and plants with and without fruits source leaves) and five repetitions consisting of individual plants. After analysing the variance of the results it was applied Student t test at the level of 5 % of significance to compare the averages between the treatments. The total phenol grade (µg g-1) have been extracted from the mature (source) and new (drain) leaves and have been analyzed in relation to the coffee yield, phenology and climate. The climatic conditions adopted were atmospheric temperature (average, minimum and maximum; oC), global radiation (MJ m-2 day-1) and daily insolation (h day-1). During the conduction of the experiment it was analyzed the evaluations of the height (cm), diameter (mm) and length of the reproductive branches (cm) to determine the respective vegetative growth rates of the plants. The determined amounts of total phenols in the plants with production (17.40 µg g-1 and 13.89 µg g-1 drain and source leaves, respectively) and without coffee production (18.65 µg g-1 and 12.76 µg g-1 drain and source leaves, respectively) did not varied. However, the total phenol concentrations in new leaves of the plants with and without coffee production were greater than the amount determined in mature leaves around 25 % and 46 %, respectively. The secondary substance synthesis in the phases of expansion (16.35 µg g-1) and grain filling of the fruits (14.68 µg g-1) was 31% lower than the amounts determined in the phase of the greatest production of these substances - fruit in maturation (21.24 µg g-1). The total phenol metabolization depends indirectly on the temperature (oC) and on the global radiation (MJ m-2 day-1), presenting inverse trend in relation to these climatic variable. The orientation of the crop protection managing shall take into consideration the period when it has endangerment of the natural defense of the plant.
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Microesferas magnéticas de quitosana para remoção do corante violeta de metila 2B em meio aquosoToaldo, Luciane Torezan 09 March 2015 (has links)
A crescente utilização de corantes na indústria gera grande quantidade de resíduos.Estes, quando descartados inadequadamente, tornam-se uma fonte poluidora dos sistemas aquáticos, os quais são indispensáveis à vida e à manutenção do equilíbrio de ecossistemas naturais. Por este motivo, é importante que sejam desenvolvidos métodos de tratamento eficazes para a remoção de corantes. Dentro desse contexto, este trabalho teve por objetivo avaliar a capacidade de adsorção de microesferas magnéticas de quitosana na remoção do corante violeta de metila 2B (VM 2B) em meio aquoso. Inicialmente, preparou-se magnetita (Fe3O4) através da precipitação química dos sais de ferro (II) e (III), em meio alcalino. A etapa seguinte consistiu na preparação das microesferas de quitosana, por meio da técnica de reticulação em suspensão, utilizando glutaraldeído. Com o objetivo de conferir propriedades magnéticas à quitosana, adicionou-se a Fe3O4 anteriormente preparada. Estes materiais foram caracterizados quanto a sua morfologia e características químicas. Os parâmetros experimentais do processo de adsorção foram previamente otimizados, variando-se a massa de adsorvente, a velocidade de agitação do sistema e o pH inicial do meio. A capacidade adsorvente das microesferas magnéticas de quitosana foi avaliada em um sistema em batelada, sob temperatura controlada de 25 °C, sendo a concentração remanescente de VM 2B em solução determinada por espectroscopia de absorção molecular na região do visível. Os resultados revelaram que as microesferas magnéticas de quitosana apresentam potencial para a finalidade proposta, com elevada capacidade de remoção para o corante VM 2B (~86%). Os resultados experimentais mostraram que a cinética de adsorção foi melhor descrita pelo modelo de pseudossegunda ordem. No que se refere ao equilíbrio de adsorção, os resultados experimentais apresentaram um melhor ajuste à isoterma de Freundlich (R2 superior a 0,98). Os dados termodinâmicos revelaram um processo de adsorção espontâneo ( G°= -3,96 kJ mol-1), exotérmico ( H° = -1,70 kJ mol-1), e com S° = -3,73 J mol-1 K-1, o que sugere pequena mudança na aleatoriedade na interface sólido-soluto durante a adsorção. / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior. / The increasing use of dyes in the industry generates great quantities of waste. When disposed improperly, they become a source of pollution of aquatic systems which are essential to life and to maintain the equilibrium of natural ecosystems. For this reason, it is important to develop effective treatment methods for the removal of dyes. In this context, this work aimed to evaluate the adsorption capacity of magnetic chitosan microspheres for the removal of methyl violet 2B (MV 2B) dye in aqueous media. Initially, magnetite (Fe3O4) was prepared by chemical precipitation of iron salts (II) and (III). Then, chitosan microspheres were prepared by the suspension crosslinking technique. Finally, Fe3O4 was added to chitosan in order to achieve magnetic properties. These materials were characterized by their morphology and chemical characteristics. The experimental parameters of the adsorption process were optimized by varying the mass of adsorbent, the stirring rate, and the initial pH of the medium. The adsorbent capacity of magnetic chitosan microspheres was evaluated in a batch system at 25 °C. After the adsorption process in an aqueous medium, the remaining concentration of MV 2B solution was determined by molecular absorption spectroscopy in the visible region. The results showed that the magnetic chitosan microspheres present a high potential for the purpose, with a high capacity for removing MV 2B (~86%). The adsorption process followed pseudo-second-order rate kinetics, and the adsorption equilibrium was better described by the Freundlich isotherm (R2 higher than 0.98). The thermodynamic data revealed a spontaneous ( G° = -3.96 kJ mol-1), exothermic ( H° = -1.70 kJ mol-1), and S° = -3.73 J mol-1 K-1, which suggests a small variation in the randomness at the solidsolution interface.
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A Search for Periodic and Quasi-Periodic Patterns in Select Proxy Data with a Goal to Understanding Temperature VariationOtto, James (James Robert) 05 1900 (has links)
In this work over 200 temperature proxy data sets have been analyzed to determine if periodic and or quasi-periodic patterns exist in the data sets. References to the journal articles where data are recorded are provided. Chapter 1 serves an introduction to the problem of temperature determination in providing information on how various proxy data sources are derived. Examples are given of the techniques followed in producing proxy data that predict temperature for each method used. In chapter 2 temperature proxy data spanning the last 4000 years, from 2,000 BCE to 2,000 CE, are analyzed to determine if overarching patterns exist in proxy data sets. An average of over 100 proxy data sets was used to produce Figure 4. An overview of the data shows that several “peaks” can be identified. The data were then subjected to analysis using a series of frequency modulated cosine waves. This analysis led to a function that can be expressed by equation 3. The literature was examined to determine what mathematical models had been published to fit the experimental proxy data for temperature. A number of attempts have been made to fit data from limited data sets with some degree of success. Some other papers have used a sinusoidal function to best fit the changes in the temperature. After consideration of many published papers and reviewing long time streams of proxy data that appeared to have sine wave patterns, a new model was proposed for trial. As the patterns observed showed “almost” repeating sine cycles, a frequency modulated sine wave was chosen to obtain a best fit function. Although other papers have used a sinusoidal function to best fit the changes in the temperature, the “best fit” was limited. Thus, it was decided that a frequency modulated sine wave may be a better model that would provide a more precise fit. This proved to be the case and the more than 240 temperature proxy data sets were analyzed using Equation 3. In chapter 3 the time span for the proxy data was extended to cover the period of time 12,000 BCE to 2000 CE. The data were then tested by using the equation above to search for periodic/quasi-periodic patterns. These results are summarized under select conditions of time periods. In chapter 4 the interval of time is extended over 1,000,000 years of time to test for long period “periodic” changes in global temperature. These results are provided for overall analysis. The function f(x) as described above was used to test for periodic/quasi-periodic changes in the data. Chapter 5 provides an analysis of temperature proxy data for an interval of time of 3,000,000 years to establish how global temperature has varied during the last three million years. Some long-term quasi-periodic patterns are identified. Chapter 6 provides a summation of the model proposed for global temperature that can be expected if similar trends continue over future years as have prevailed for the past few million years. Data sets that were used in this work are tabulated in the appendices of this paper.
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Environment driven consumer EC model incorporating complexities of consumer body dynamicsAli, S.M., Khan, B., Mokryani, Geev, Mehmood, C.A., Jawad, M., Farid, U. 18 February 2019 (has links)
Yes / Energy consumption (EC) of consumers primarily depends on comfort level (CL) affirmed by brain sensations of the central nervous system. Environmental parameters such as surroundings, relative humidity, air temperature, solar irradiance, air pressure, and cloud cover directly influence consumer body temperature that in return affect blood dynamics perturbing brain comfort sensations. This CL (either in summer, winter, autumn, or spring season) is a function of external environment and internal body variations that force a consumer toward EC. To develop a new concept of consumer's EC, first the authors described environment parameters in detail with relation to surroundings and EC. Considering this, they tabulated a generic relation of consumer's CL with EC and environment temperature. Second, to build an inter-related bond between the environmental effects on consumer body dynamics, they analysed theoretically and mathematically above mutual relations between medical and environmental sciences. Finally, they present their conceptual EC model based on a closed-loop feedback system. This model is a complex non-linear adaptive system with environmental and surrounding parameters as input to the system resulting in an optimised EC, considering consumer CL as a key parameter for the system.
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Condições de estresse e conforto térmico em fábrica de pré-moldado em Ponta Grossa - PR / Conditions of heat stress and thermal comfort in precast industry in Ponta Grossa - PRGalvan, Tanise Fuckner de Oliveira 28 February 2018 (has links)
O estresse térmico é um risco reconhecido a que os trabalhadores de várias indústrias estão expostos. De forma a verificar a condição de estresse e também conforto térmico na fábrica de pré-moldado em concreto, foi realizada uma pesquisa na qual as variáveis ambientais e pessoais foram obtidas através de medições e questionários. A avaliação preliminar do estresse térmico foi realizada pela escala HSSI, a qual indicou a não existência do mesmo nessa fábrica. Foi efetuada a avaliação do ambiente, através dos índices IBUTG e PHS, que ratificaram a não existência do estresse térmico. Como não houve a incidência do estresse térmico, o ambiente foi avaliado com relação ao conforto térmico, nas medições em que o índice PMV era aplicável, e foi calculado o índice PET. Através do cálculo do índice do PMV, verificou-se que em apenas uma medição o ambiente pode ser considerado confortável, nas demais o ambiente é considerado desconfortável termicamente. Os resultados do índice PET, demonstram que na maioria das medições também ficou caracterizada o desconforto térmico. / Heat stress is a recognized risk that workers in various industries are exposed. In order to verify the stress condition and also thermal comfort in the precast concrete factory, a research was carried out in which the environmental and personal variables were obtained through measurements and questionnaires. The preliminary evaluation of the heat stress was performed by the HSSI scale, which indicated the absence of heat stress in this factory. To confirm this conclusion, the evaluation of the environment was carried out through the IBUTG and PHS indices, which confirmed the absence of heat stress. As there was no incidence of heat stress, the environment was evaluated with respect to thermal comfort, in the measurements in which the PMV index was applicable and the PET index was calculated. Through the calculation of the PMV index, it was verified that in only one measurement the environment can be considered comfortable, in the others the environment is considered to be thermally uncomfortable. Through the calculation of the PMV index, it was verified that in only one measurement the environment can be considered comfortable, in the others the environment is considered to be thermally uncomfortable. The results of the PET index show that thermal discomfort was also characterized in most of the measurements.
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