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Processes controlling atmospheric dispersion through city centres
We develop a process-based model for the dispersion of a passive scalar in the turbulent flow around the buildings of a city centre. The street network model is based on dividing the airspace of the streets and intersections into boxes, within which the turbulence renders the air well mixed. Mean flow advection through the network of street and intersection boxes then mediates further lateral dispersion. At the same time turbulent mixing in the vertical detrains scalar from the streets and intersections into the turbulent boundary layer above the buildings. When the geometry is regular, the street network model has an analytical solution that describes the variation in concentration in a near-field downwind of a single source, where the majority of scalar lies below roof level. The power of the analytical solution is that it demonstrates how the concentration is determined by only three parameters. The plume direction parameter describes the branching of scalar at the street intersections and hence determines the direction of the plume centreline, which may be very different from the above-roof wind direction. The transmission parameter determines the distance travelled before the majority of scalar is detrained into the atmospheric boundary layer above roof level and conventional atmospheric turbulence takes over as the dominant mixing process. Finally, a normalised source strength multiplies this pattern of concentration. This analytical solution converges to a Gaussian plume after a large number of intersections have been traversed, providing theoretical justification for previous studies that have developed empirical fits to Gaussian plume models. The analytical solution is shown to compare well with very high-resolution simulations and with wind tunnel experiments, although re-entrainment of scalar previously
detrained into the boundary layer above roofs, which is not accounted for in the analytical solution, is shown to become an important process further downwind from the source
Eficiência energética da envoltória de edifícios de escritórios de Florianópolis: discussões sobre a aplicação do método prescritivo do RTQ-C
Ocorrência de adultos de Drosophila suzukii (Matsumura, 1931) (Diptera: Drosophilidae) em pontos comerciais na área urbana de Vacaria-RS.
Este estudo teve como objetivos avaliar a ocorrência de exemplares adultos de D. suzukii nas proximidades de mercados de comercialização de frutas em área urbana
Scalar Quantum Field Theory in Disordered Media
A free massive scalar field in inhomogeneous random media is investigated.
The coefficients of the Klein-Gordon equation are taken to be random functions
of the spatial coordinates. The case of an annealed-like disordered medium,
modeled by centered stationary and Gaussian processes, is analyzed. After
performing the averages over the random functions, we obtain the two-point
causal Green's function of the model up to one-loop. The disordered scalar
quantum field theory becomes qualitatively similar to a
self-interacting theory with a frequency-dependent coupling
SIMULATION AND PERFORMANCE ANALYSIS OF A HYBRID ROCKET ENGINE WITH SELF-PRESSURIZING OXIDIZER
There are many challenges to simulate and design a hybrid engine, such as the dimensioning of the feed lines and tanks, propulsive performance calculations, and simulations of the expected behavior in the combustion chamber and the oxidizer tank during the engine operation. In this work, methods are assembled in a concise and complete analysis of the Gluon hybrid rocket engine, developed by PION Labs, with a blowdown pressurization system, using N2O as oxidizer and a paraffin-based fuel. For that, a study will be presented on the peculiar characteristics of the oxidizer and its behavior during the phases of operation of the rocket engine. Then, the main equations that describe the operation of the rocket engine, including the combustion chamber, injection plate, feed lines, and the oxidizer tank are presented, and the performance indicators calculations of the engine are shown and discussed. Finally, simulation results of the combustion chamber and the oxidizer tank during engine firing will be presented, leading to the concluding remarks on the data obtained
Contribuição ao desenvolvimento de linhagens de soja com resistência a patógenos.
RESUMO: As doenças que ocorrem na soja são responsáveis por severas perdas para os produtores em todo o mundo. Para o controle das principais doenças, a maneira mais prática e econômica tem sido o uso da resistência genética. Objetivando um melhor uso do germoplasma de soja disponível, métodos de seleção de plantas com resistência a Meloidogyne javanica, Heterodera glycines, Diaporthe phaseolorum, Microsphaera dissusa, Fusairum solani, Cercospora sojina e ao vírus da necrose da haste são apresentados. As linhagens avaliadas foram obtidas dos cruzamentos BRS 133 x PI 595099 e Coodetec 201 x PI 595099. Informações adicionais sobre os patógenos abordados e duraçãodo ciclo e produtividade das linhagens avaliadas são também apresentadas. ABSTRACT: Soybean diseases have been responsible for severe losses to the farmers around the world. The most practical, clean and economic way to control plant diseases is through the use of genetic resistance. In order to make the most effective use of available germoplam, methods for selection of soybeans plants with resistance to Meloidogyne javanica, Heterodera glycines, Diaporthe phaseolorum, Microsphaera diffusa, Fusarium solani, Cercospora sojina and cowpea mild mottle virus are presented. Moreover, information about the pathogens, soybean maturity group and yield are also presented.bitstream/item/69809/1/Boletim-de-pesquisa-e-desenvolvimento-1.pd
Tratamento de dados climáticos de Santa Maria, RS, para análise de desempenho térmico de edificações
Resumo O tratamento e a disponibilização de dados climáticos para projeto de edificações são importantes para seu desempenho térmico e eficiência energética. O Ano Climático de Referência (TRY), o Ano Meteorológico Típico (TMY2), a carta bioclimática, arquivos EPW e CVS, diagrama de ventos e o dia típico de projeto são os tratamentos mais comuns. Para Santa Maria - RS, algumas destas sistematizações já existiam, porém para um período de oito anos. O objetivo do estudo foi tratar e analisar dados climáticos para Santa Maria, complementando estudos anteriores, ampliando a base de dados para doze anos e atualizando seu tratamento. O estudo baseou-se em bibliografia científica e metodologias que vêm sendo empregadas por vários pesquisadores. Os resultados apontam maior desconforto por frio. A radiação solar é bem distribuída ao longo do ano, indicando aquecimento solar passivo, no inverno, e sombreamento, no verão. O arquivo TMY2 gerado no estudo tem comportamento similar ao TRY-INMET (2012) e apresenta diferenças mais significativas quando comparado ao SWERA. Observou-se a importância das orientações norte e nordeste, para aquecimento solar, e leste, para ventilação. Os métodos apresentados podem ser aplicados a outras localidades com dados horários disponíveis
Arylated and dihydrofuran naphthoquinones: electrochemical parameters, evaluation of antitumor activity and their correlation.
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Selectivity of latifolicides associated with glyphosate applied in postemergence on soybean (Glycine max) cultivars.
Abstract: The genetic improvement of soybean cultivars over the years has focused on increasing the yield potential and tolerance to some abiotic and biotic factors. However, during the transfer of genes of interest, some genes responsible for a lower tolerance to herbicides can be integrated into the genome of the new cultivar. Thus, the objective of this study was to evaluate the selectivity of herbicide associations applied in the postemergence period of three soybean cultivars. The experiment was conducted in a randomized completely block design, with four replications. The selected cultivars were M7110 IPRO®, Foco IPRO®, and Bônus IPRO®. The herbicides and the respective doses (g a.i. ha-1) used were glyphosate (1176), glyphosate + bentazon (1176 + 600), glyphosate + fomesafen (1176 + 175), glyphosate + lactofen (1176 + 120), glyphosate + imazethapyr (1176 + 100), glyphosate + chlorimuron (1176 + 10), glyphosate + cloransulam (1176 + 39.5), and a control without herbicide application. The visual note of intoxication was evaluated for each treatment. The components of growth and yield evaluated were height, stand, weight of one hundred grains, and yield. The application of postherbicide herbicides did not alter the plant stands of soybean cultivars. Additionally, these herbicides did not reduce the yield of the M7110 IPRO® and Foco IPRO® cultivars. Glyphosate isolated and in association with lactofen or imazethapyr reduced the grain yield of the Bônus IPRO® cultivar. -- Resumen: El mejoramiento genético de los cultivares de soja a lo largo de los años se ha centrado en aumentar la capacidad productiva y la tolerancia a algunos factores abióticos y bióticos. Sin embargo, durante la transferencia de genes de interés, algunos genes responsables de una menor tolerancia a los herbicidas pueden integrarse en el genoma del nuevo cultivar. El objetivo de este estudio fue evaluar la selectividad de las asociaciones de herbicidas aplicadas en la post-emergencia de tres cultivares de soja. El diseño experimental utilizado fue un bloque completamente al azar, con cuatro repeticiones. Los cultivares seleccionados fueron M7110 IPRO®, Foco IPRO® y Bônus IPRO®. Los herbicidas y las respectivas dosis (g a.i. ha-1) utilizados fueron: glyphosate (1176), glyphosate + bentazon (1176 + 600), glyphosate + fomesafen (1176 + 175), glyphosate + lactofen (1176 + 120), glyphosate + imazethapyr (1176 + 100), glyphosate + chlorimuron (1176 + 10), glyphosate + cloransulam (1176 + 39,5), y un control sin aplicación de herbicida. Se hizo una nota visual de intoxicación para cada tratamiento. Los componentes de crecimiento y rendimiento evaluados fueron: altura, rodal, peso de cien granos y rendimiento. La aplicación de herbicidas en post-emergencia no alteró la masa vegetal de los cultivares de soja. Además, estos herbicidas no redujeron el rendimiento de los cultivares M7110 IPRO® y Foco IPRO®. Tanto el glifosato aislado como mezclado con lactofen o imazethapyr redujeron el rendimiento del cultivar Bônus IPRO®
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