32 research outputs found
Efeito de fontes de cálcio na firmeza do tomate.
O objetivo deste trabalho foi avaliar a firmeza do tomate em função da pulverização com fontes de cálcio. O experimento foi conduzido em casa de vegetação no período de janeiro a maio de 2011. O delineamento experimental utilizado foi blocos casualizados com quatro repetições e sete tratamentos (pulverização com fontes de Ca+ solúveis ou dispersíveis em água). Foi avaliada a firmeza de frutos em duas épocas de colheita. Observou-se que os tratamentos avaliados não influenciaram a firmeza do tomate
Efeito da adubação potássica no sabor de morangos.
O objetivo deste trabalho foi avaliar o efeito da adubação potássica sobre o sabor de morangos das cultivares Camino Real, Festival e Oso Grande
Aerothermodynamic comparison of two- and three-dimensional rarefied hypersonic cavity flows
The thermal protection system is a key element in atmospheric re-entry missions of aerospace vehicles. Usually, in the thermal load calculations, the analysis assumes that the vehicle has a smooth surface. However, discontinuities or imperfections are often present on the aerospace vehicle surfaces due to fabrication tolerances, sensor installations, spaces between the thermal protection plates, and differential expansion or ablation rates between non-similar materials. In the present work, rarefied hypersonic flows over two- and three-dimensional cavities at an altitude of 80km in the Earth’s atmosphere are studied numerically. To model flows in the transitional regime, where the validity of the Navier Stokes equations is questionable, the direct simulation Monte Carlo method has been used. The primary goal is to assess the sensitivity of heat transfer, pressure, and skin-friction coefficients for a family of two- and three-dimensional cavities defined by different length-to-depth ratios. The analysis shows that an assumption of two-dimensionality plays a key role in the over prediction of the aerodynamic properties. Previous work using a continuum approach shows that two recirculation regions and flow attachment occurs when the length-to-depth ratio is equal to 14; however, the same phenomena are observed in the transitional regime when the cavity length-to-depth ratio is equal to 4. A study of the influence of the cavity width has also been conducted. It is shown that increasing the cavity width results in an augmentation of the surface aerothermodynamic quantitie
Fitotoxicidade de herbicidas residuais ao sorgo sacarino implantado em sucessão à cana-de-açúcar.
Evolution of weed occurrence in soybean area planted or not with rapeseed in winter - a long-term trial.
Open source Direct Simulation Monte Carlo (DSMC) chemistry modelling for hypersonic flows
An open source implementation of chemistry modelling for the direct simulation Monte Carlo (DSMC) method is presented. Following the recent work of Bird [1] an approach known as the quantum kinetic (Q-K) method has been adopted to describe chemical reactions in a 5-species air model using DSMC procedures based on microscopic gas information. The Q-K technique has been implemented within the framework of the dsmcFoam code, a derivative of the open source CFD code OpenFOAM. Results for vibrational relaxation, dissociation and exchange reaction rates for an adiabatic bath demonstrate the success of the Q-K model when compared with analytical solutions for both inert and reacting conditions. A comparison is also made between the Q-K and total collision energy (TCE) chemistry approaches for a hypersonic flow benchmark case
Composição de plantas daninhas em áreas agrícolas consolidadas em função do preparo do solo.
bitstream/item/111424/1/17-composicao-diogo.pd
Banco de sementes de plantas daninhas em áreas de pinhão-manso consorciado com culturas nas entrelinhas.
bitstream/item/111369/1/10-banco-sabrina.pd