Produtividade e classificação de brócolos para indústria em função da adubação nitrogenada e potássica e dos espaçamentos entre plantas

No município de Itatiba-SP, no período de março a julho de 2007, foi realizado um experimento com o objetivo de avaliar doses de nitrogênio e potássio e espaçamentos entre plantas na produtividade e classificação de brócolos para indústria. O experimento foi instalado sob delineamento de blocos ao acaso, com os tratamentos em esquema fatorial 5 x 4, e três repetições, sendo avaliadas as doses de nitrogênio-potássio: 105-105; 157,5-157,5; 210-210; 262,5-262,5 e 315-315 kg ha-1 de N e K2O e os espaçamentos entre plantas: 0,2; 0,3; 0,4 e 0,5 m. O espaçamento entre linhas foi de 0,8 m. Foram avaliados o teor foliar de nitrogênio (TN) e de potássio (TP), produtividade de inflorescência (PI), produtividade de floretes (PF), rendimento industrial (RI) e classificação dos floretes com base em seu comprimento: PF5 (<5 cm); PF57 (>5 e <7 cm); PF79 (>7 e <9 cm) e PF9 (>9 cm). Maiores espaçamentos entre plantas proporcionaram maior TN e menores PI e PF. As doses NK e os espaçamentos entre plantas não influenciaram significativamente o TP e o RI. As maiores produtividades de inflorescências (22,08 t ha-1) e de floretes (17,09 t ha-1) foram obtidas com 0,20 m entre plantas e 315 kg ha-1 de N e de K2O. Maior percentagem de floretes na classe PF5 foi obtida no menor espaçamento entre plantas. As doses NK e os espaçamentos entre plantas não influenciaram as percentagens de floretes nas classes PF79 e PF9.

Qualidade de frutos de cinco híbridos de melão rendilhado em função do número de frutos por planta

Este trabalho teve por objetivo avaliar a qualidade de cinco híbridos de melão rendilhado, com dois e três frutos por planta, utilizando fibra da casca de coco e fertirrigação. Para tanto, foi instalado um experimento em casa de vegetação na UNESP-FCAV, Câmpus de Jaboticabal, com delineamento experimental em blocos ao acaso, em esquema fatorial 5 x 2, com quatro repetições. Os fatores avaliados foram cinco híbridos de melão rendilhado (Maxim, Bônus nº 2, Shinju 200, Fantasy e Louis) e número de frutos por planta (2 ou 3 frutos). Os frutos foram colhidos quando atingiram o máximo do desenvolvimento. Foram avaliados: sólidos solúveis, acidez titulável, pH, vitamina C e massa média dos frutos. Para todas as características avaliadas, não houve interação entre híbridos e o número de frutos por planta. Com base nos resultados obtidos, conclui-se que o híbrido Bônus nº 2 apresentou o maior número de características qualitativas desejáveis quando cultivada sob ambiente protegido, utilizando fibra da casca de coco e fertirrigação. O número de frutos por planta não afetou as características qualitativas avaliadas, exceto o teor de sólidos solúveis e massa média dos frutos, sendo maior quando deixados dois frutos por planta.

Formulação de rações para poedeiras com base em aminoácidos totais e digestíveis utilizando diferentes estimativas da composição de aminoácidos em alimentos

Foram utilizadas poedeiras comerciais com 27 semanas de idade, distribuídas em delineamento inteiramente ao acaso, em esquema fatorial 3 x 3, com três repetições de seis aves por tratamento. Os fatores consistiram de três métodos de estimativa da composição de aminoácidos em ingredientes (tabelas brasileiras, equações de predição e fator para correção de aminoácido em função do teor de proteína do ingrediente) e três recomendações de aminoácidos, sendo duas de aminoácidos digestíveis e uma de aminoácidos totais. Os métodos de estimativa da composição de aminoácidos nos ingredientes afetaram apenas a conversão alimentar e a espessura de casca, que apresentaram os melhores resultados com a utilização das tabelas brasileiras. Embora as recomendações de aminoácidos tenham determinado diferenças em todos os parâmetros de desempenho, não afetaram a qualidade dos ovos. O desempenho das aves foi prejudicado pelos níveis de aminoácidos digestíveis, entretanto, ambas as recomendações promoveram desempenho semelhante e inferior ao de aminoácidos totais. O pior desempenho das aves alimentadas com as rações formuladas com aminoácidos digestíveis pode ser atribuído à deficiência em nitrogênio para a síntese de aminoácidos não-essenciais, visto que o nível protéico foi reduzido (12,5% PB), ou ainda à deficiência nos aminoácidos arginina, histidina, isoleucina, leucina e valina, cujos requerimentos mínimos não foram considerados na formulação das rações.

Uso de técnicas de otimização baseadas em derivadas como suporte do planejamento operacional de redes de distribuição de energia elétrica

The usual programs for load flow calculation were in general developped aiming the simulation of electric energy transmission, subtransmission and distribution systems. However, the mathematical methods and algorithms used by the formulations were based, in majority, just on the characteristics of the transmittion systems, which were the main concern focus of engineers and researchers. Though, the physical characteristics of these systems are quite different from the distribution ones. In the transmission systems, the voltage levels are high and the lines are generally very long. These aspects contribute the capacitive and inductive effects that appear in the system to have a considerable influence in the values of the interest quantities, reason why they should be taken into consideration. Still in the transmission systems, the loads have a macro nature, as for example, cities, neiborhoods, or big industries. These loads are, generally, practically balanced, what reduces the necessity of utilization of three-phase methodology for the load flow calculation. Distribution systems, on the other hand, present different characteristics: the voltage levels are small in comparison to the transmission ones. This almost annul the capacitive effects of the lines. The loads are, in this case, transformers, in whose secondaries are connected small consumers, in a sort of times, mono-phase ones, so that the probability of finding an unbalanced circuit is high. This way, the utilization of three-phase methodologies assumes an important dimension. Besides, equipments like voltage regulators, that use simultaneously the concepts of phase and line voltage in their functioning, need a three-phase methodology, in order to allow the simulation of their real behavior. For the exposed reasons, initially was developped, in the scope of this work, a method for three-phase load flow calculation in order to simulate the steady-state behaviour of distribution systems. Aiming to achieve this goal, the Power Summation Algorithm was used, as a base for developing the three phase method. This algorithm was already widely tested and approved by researchers and engineers in the simulation of radial electric energy distribution systems, mainly for single-phase representation. By our formulation, lines are modeled in three-phase circuits, considering the magnetic coupling between the phases; but the earth effect is considered through the Carson reduction. It s important to point out that, in spite of the loads being normally connected to the transformer s secondaries, was considered the hypothesis of existence of star or delta loads connected to the primary circuit. To perform the simulation of voltage regulators, a new model was utilized, allowing the simulation of various types of configurations, according to their real functioning. Finally, was considered the possibility of representation of switches with current measuring in various points of the feeder. The loads are adjusted during the iteractive process, in order to match the current in each switch, converging to the measured value specified by the input data. In a second stage of the work, sensibility parameters were derived taking as base the described load flow, with the objective of suporting further optimization processes. This parameters are found by calculating of the partial derivatives of a variable in respect to another, in general, voltages, losses and reactive powers. After describing the calculation of the sensibility parameters, the Gradient Method was presented, using these parameters to optimize an objective function, that will be defined for each type of study. The first one refers to the reduction of technical losses in a medium voltage feeder, through the installation of capacitor banks; the second one refers to the problem of correction of voltage profile, through the instalation of capacitor banks or voltage regulators. In case of the losses reduction will be considered, as objective function, the sum of the losses in all the parts of the system. To the correction of the voltage profile, the objective function will be the sum of the square voltage deviations in each node, in respect to the rated voltage. In the end of the work, results of application of the described methods in some feeders are presented, aiming to give insight about their performance and acuity

Um algoritmo para estimação de estado em alimentadores de distribuição de energia elétrica com base no método da soma de potências

Most algorithms for state estimation based on the classical model are just adequate for use in transmission networks. Few algorithms were developed specifically for distribution systems, probably because of the little amount of data available in real time. Most overhead feeders possess just current and voltage measurements at the middle voltage bus-bar at the substation. In this way, classical algorithms are of difficult implementation, even considering off-line acquired data as pseudo-measurements. However, the necessity of automating the operation of distribution networks, mainly in regard to the selectivity of protection systems, as well to implement possibilities of load transfer maneuvers, is changing the network planning policy. In this way, some equipments incorporating telemetry and command modules have been installed in order to improve operational features, and so increasing the amount of measurement data available in real-time in the System Operation Center (SOC). This encourages the development of a state estimator model, involving real-time information and pseudo-measurements of loads, that are built from typical power factors and utilization factors (demand factors) of distribution transformers. This work reports about the development of a new state estimation method, specific for radial distribution systems. The main algorithm of the method is based on the power summation load flow. The estimation is carried out piecewise, section by section of the feeder, going from the substation to the terminal nodes. For each section, a measurement model is built, resulting in a nonlinear overdetermined equations set, whose solution is achieved by the Gaussian normal equation. The estimated variables of a section are used as pseudo-measurements for the next section. In general, a measurement set for a generic section consists of pseudo-measurements of power flows and nodal voltages obtained from the previous section or measurements in real-time, if they exist -, besides pseudomeasurements of injected powers for the power summations, whose functions are the load flow equations, assuming that the network can be represented by its single-phase equivalent. The great advantage of the algorithm is its simplicity and low computational effort. Moreover, the algorithm is very efficient, in regard to the accuracy of the estimated values. Besides the power summation state estimator, this work shows how other algorithms could be adapted to provide state estimation of middle voltage substations and networks, namely Schweppes method and an algorithm based on current proportionality, that is usually adopted for network planning tasks. Both estimators were implemented not only as alternatives for the proposed method, but also looking for getting results that give support for its validation. Once in most cases no power measurement is performed at beginning of the feeder and this is required for implementing the power summation estimations method, a new algorithm for estimating the network variables at the middle voltage bus-bar was also developed

Uso de técnicas de otimização baseadas em derivadas como suporte do planejamento operacional de redes de distribuição de energia elétrica

The usual programs for load flow calculation were in general developped aiming the simulation of electric energy transmission, subtransmission and distribution systems. However, the mathematical methods and algorithms used by the formulations were based, in majority, just on the characteristics of the transmittion systems, which were the main concern focus of engineers and researchers. Though, the physical characteristics of these systems are quite different from the distribution ones. In the transmission systems, the voltage levels are high and the lines are generally very long. These aspects contribute the capacitive and inductive effects that appear in the system to have a considerable influence in the values of the interest quantities, reason why they should be taken into consideration. Still in the transmission systems, the loads have a macro nature, as for example, cities, neiborhoods, or big industries. These loads are, generally, practically balanced, what reduces the necessity of utilization of three-phase methodology for the load flow calculation. Distribution systems, on the other hand, present different characteristics: the voltage levels are small in comparison to the transmission ones. This almost annul the capacitive effects of the lines. The loads are, in this case, transformers, in whose secondaries are connected small consumers, in a sort of times, mono-phase ones, so that the probability of finding an unbalanced circuit is high. This way, the utilization of three-phase methodologies assumes an important dimension. Besides, equipments like voltage regulators, that use simultaneously the concepts of phase and line voltage in their functioning, need a three-phase methodology, in order to allow the simulation of their real behavior. For the exposed reasons, initially was developped, in the scope of this work, a method for three-phase load flow calculation in order to simulate the steady-state behaviour of distribution systems. Aiming to achieve this goal, the Power Summation Algorithm was used, as a base for developping the three phase method. This algorithm was already widely tested and approved by researchers and engineers in the simulation of radial electric energy distribution systems, mainly for single-phase representation. By our formulation, lines are modeled in three-phase circuits, considering the magnetic coupling between the phases; but the earth effect is considered through the Carson reduction. Its important to point out that, in spite of the loads being normally connected to the transformers secondaries, was considered the hypothesis of existence of star or delta loads connected to the primary circuit. To perform the simulation of voltage regulators, a new model was utilized, allowing the simulation of various types of configurations, according to their real functioning. Finally, was considered the possibility of representation of switches with current measuring in various points of the feeder. The loads are adjusted during the iteractive process, in order to match the current in each switch, converging to the measured value specified by the input data. In a second stage of the work, sensibility parameters were derived taking as base the described load flow, with the objective of suporting further optimization processes. This parameters are found by calculating of the partial derivatives of a variable in respect to another, in general, voltages, losses and reactive powers. After describing the calculation of the sensibility parameters, the Gradient Method was presented, using these parameters to optimize an objective function, that will be defined for each type of study. The first one refers to the reduction of technical losses in a medium voltage feeder, through the installation of capacitor banks; the second one refers to the problem of correction of voltage profile, through the instalation of capacitor banks or voltage regulators. In case of the losses reduction will be considered, as objective function, the sum of the losses in all the parts of the system. To the correction of the voltage profile, the objective function will be the sum of the square voltage deviations in each node, in respect to the rated voltage. In the end of the work, results of application of the described methods in some feeders are presented, aiming to give insight about their performance and acuity

Estudo térmico e de materiais na construção de casas populares com blocos confeccionados a partir de um composto a base de cimento, gesso, eps e raspa de pneu

We built an experimental house on an UFRN´s land using blocks made by a composite consisting of cement, plaster, EPS, crushed rubber and sand. Several blocks were made from various compositions and we made preliminary tests of mechanical and thermal resistance, choosing the most appropriate proportion. PET bottles were used inside the block to provide thermal resistance. In this work, a second function was given to the bottles: to serve as a docking between the blocks, because the ends of the cylinders came out of each block on top as well as at the bottom, with the bottom cut, allowing to fit of the extremities of the upper cylinder of a block in the lower holes of the other one, which were formed by the cutting already mentioned. Minimum compression tests were performed according to ABNT standards for walls closing blocks (fence). With that house built, we did studies of thermal performance in order to ascertain conditions of comfort, checking external and internal temperatures in the walls and in the ambient, among other variables, such as wind speed and relative humidity. The resulting blocks provided adequate thermal insulation to the environment, where the walls presented differences up to 11.7 ºC between the outer and inner faces, getting the maximum temperature inside the house around 31 °C, within the so-called thermal comfort zone for warm climates. At the end of the experiments it was evident the effectiveness of that construction in order to provide thermal comfort in the internal environment of the house, as well as we could confirm the viability of building houses from recyclable materials, reducing the constructive costs, becoming a suitable alternative for low- incoming families. Moreover, besides the low cost, the proposal represents an alternative use of various recyclable materials, therefore considered an ecological solution

RAPD analysis of genetic variability in a multiprovenance base population of Eucalyptus grandis hill ex maiden

Este estudo visou avaliar a variabilidade e distância genética dentro de uma população-base de melhoramento genético de Eucalyptus grandis. A avaliação da variabilidade genética tem como objetivos principais analisar a base genética da população-base e montar um banco de dados marcadores moleculares da população em análise. Essa população é formada por 327 indivíduos, principalmente das procedências de Coff's Harbour, Atherton e Rio Claro. Devido à heterozigosidade natural dessa população, ela pode ser dividida em diversas subpopulações, de acordo com a latitude e longitude de origem; e dentro de subpopulações, em função do grau de melhoramento genético já realizado do material analisado no Brasil. Isso permitiu avaliar quanto da variabilidade detectada dentro da população-base foi devido a esses fatores: procedência e grau de melhoramento. A aplicação da técnica RAPD permitiu avaliar 70 locos polimórficos, que foram analisados utilizando-se o coeficiente de Jaccard, o que resultou em matrizes de similaridade genética entre os indivíduos. Os dados de similaridade genética posteriormente foram submetidos à análise estatística. Osdados indicaram que a população-base apresenta ampla base genética, com média de similaridade genética de 0,328. O subgrupo denominado Região 3, composto por material selvagem da macrorregião de Atherton, juntamente com material de APS da macrorregião de Coff's Harbour, foi um dos que mais contribuíram para a ampla base genética da população-base. Foi possível detectar diferença estatística entre as populações selvagens das procedências de Atherton e Coff's Harbour, assim como entre essas procedências e a de Rio Claro.

Avaliação e modelagem reológica de fluido de perfuração base água

The determination of the rheology of drilling fluids is of fundamental importance to select the best composition and the best treatment to be applied in these fluids. This work presents a study of the rheological behavior of some addictives used as viscosifiers in water-based drilling fluids. The evaluated addictives were: Carboxymethylcellulose (CMC), Xanthan gum (GX), and Bentonite. The main objective was to rheologically characterize suspensions composed by these addictives, by applying mathematical models for fluid flow behavior, in order to determine the best flow equation to represent the system, as well as the model parameters. The mathematical models applied in this research were: the Bingham Model, the Ostwald de Wale Model, and the Herschel-Bulkley Model. A previous study of hydration time for each used addictive was accomplished seeking to evaluate the effect of polymer and clay hydration on rheological behavior of the fluid. The rheological characterization was made through typical rheology experiments, using a coaxial cylinder viscosimeter, where the flow curves and the thixotropic magnitude of each fluid was obtained. For each used addictive the rheological behavior as a function of temperature was also evaluated as well as fluid stability as a function of the concentration and kind of addictive used. After analyses of results, mixtures of polymer and clay were made seeking to evaluate the rheological modifications provided by the polymer incorporation in the water + bentonite system. The obtained results showed that the Ostwald de Waale model provided the best fit for fluids prepared using CMC and for fluids with Xanthan gum and Bentonite the best fit was given by the Herschel-Bulkley one

Qualidade fisiológica de sementes de palmiteiro-vermelho em função da desidratação e do armazenamento

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Componentes da produção e produtividade de cultivares de arroz e feijão em função de calcário e gesso aplicados na superfície do solo

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Preparação e caracterização de um material híbrido, à base de vermiculita modificada com quitosana, para a remoção de íons de chumbo presentes em efluentes sintéticos

Actually, surveys have been developed for obtaining new materials and methodologies that aim to minimize environmental problems due to discharges of industrial effluents contaminated with heavy metals. The adsorption has been used as an alternative technology effectively, economically viable and potentially important for the reduction of metals, especially when using natural adsorbents such as certain types of clay. Chitosan, a polymer of natural origin, present in the shells of crustaceans and insects, has also been used for this purpose. Among the clays, vermiculite is distinguished by its good ion exchange capacity and in its expanded form enhances its properties by greatly increasing its specific surface. This study aimed to evaluate the functionality of the hybrid material obtained through the modification of expanded vermiculite with chitosan in the removal of lead ions (II) in aqueous solution. The material was characterized by infrared spectroscopy (IR) in order to evaluate the efficiency of modification of matrix, the vermiculite, the organic material, chitosan. The thermal stability of the material and the ratio clay / polymer was evaluated by thermogravimetry. To evaluate the surface of the material was used in scanning electron microscopy (SEM) and (BET). The BET analysis revealed a significant increase in surface area of vermiculite that after interaction with chitosan, was obtained a value of 21, 6156 m2 / g. Adsorption tests were performed according to the particle size, concentration and time. The results show that the capacity of removal of ions through the vermiculite was on average 88.4% for lead in concentrations ranging from 20-200 mg / L and 64.2% in the concentration range of 1000 mg / L. Regarding the particle size, there was an increase in adsorption with decreasing particle size. In fuction to the time of contact, was observed adsorption equilibrium in 60 minutes with adsorption capacity. The data of the isotherms were fitted to equation Freundlich. The kinetic study of adsorption showed that the pseudo second- order model best describes the adsorption adsorption, having been found following values K2=0,024 g. mg-1 min-1and Qmax=25,75 mg/g, value very close to the calculated Qe = 26.31 mg / g. From the results we can conclude that the material can be used in wastewater treatment systems as a source of metal ions adsorbent due to its high adsorption capacity

Crescimento do milho em função da saturação por bases e da adubação potássica

Os teores de Ca, Mg e K no solo interferem no crescimento e na produção das culturas. No entanto, a relação entre esses nutrientes que proporciona o desenvolvimento adequado das plantas varia entre as espécies vegetais. O presente teve por objetivo estudar o desenvolvimento do milho em função da saturação do solo por bases e adubação potássica. O delineamento experimental foi inteiramente casualizado, com quatro repetições, em esquema fatorial 3x2x4, constituindo-se de três solos (Neossolo Quartzarênico, Latossolo Vermelho e Latossolo Bruno), dois valores de saturação por bases (40 e 70 %) e quatro doses de potássio no solo (0, 60, 120 e 240 mg kg-1). O experimento foi conduzido em casa-de-vegetação, utilizando-se o milho cv. Zêneca 8392 com uma planta por vaso de 30 L. Aos 29, 57 e 127 dias após a emergência das plântulas, efetuaram-se medidas do número de folhas por planta, altura média das plantas, diâmetro basal do colmo e comprimento médio de entrenós. Após a colheita final determinou-se a produção de grãos por planta. O desenvolvimento e a produção de grãos do milho aumentou até a adição de 60 mg kg-1 de K ao solo. O crescimento do milho foi mais rápido no solo mais arenoso, até o florescimento masculino. Solos com maior capacidade de troca catiônica proporcionaram maior comprimento de entrenós. O comprimento médio de entrenós foi inversamente relacionado ao número médio de entrenós por planta, em função do tipo de solo.

Desenvolvimento de mudas de Tabeluia chrysotricha em função de substratos e de soluções de fertirrigação

The work aimed to study the development of Tabebuia chrysotricha Standl. seedlings injunction of different substrate and different fertilization solutions. To compose the substrate it was used fibrous and granulated coconut fiber obtaining the following treatments: S1- 100% fibrous, S2- 60% fibrous and 40% granulated, S3- 40% fibrous and 60% granulated and S4- 100% granulated. The basis fertilization was the same for all treatments and the solutions of fertilization varied in order to obtain solutions with the following electric conductivities: EC1- 1.06 dS m(-1), EC2- 2.12 dS m(-1), EC3- 3.2 dS m(-1) and EC4- 4.25 dS m(-1). The propagative material was sowed directly in plastic containers (120mL) with the respective substrates. The fertilization was received through sub irrigation once a week, until the seedlings reached 20cm of height approximately. The chemical analyses of the substrate (EC and pH), through aqueous extraction method 1:1.5 (1 substrate: 1.5 deionized water), the analyses of aerial part height, stein diameter and pairs true leaves number, as well as the weight of total dry, matter, were accomplished each 15 days. In almost every analysis, the substrate with granulated coconut fiber, as well as the smallest EC (1.06 e 2.12 dS m(-1)) of fertilization solutions,formed seedlings with higher averages, indicating faster growth. In the conditions of this experiment, the production of T. chrysotricha seedlings was better in granulated coconut fiber substrate and fertilizer solutions with EC of 1.06 dS m(-1), appreciating the estimated characteristics.

Formulação de novos combustíveis base diesel: avaliação de desempenho e emissões

The industry, over the years, has been working to improve the efficiency of diesel engines. More recently, it was observed the need to reduce pollutant emissions to conform to the stringent environmental regulations. This has attached a great interest to develop researches in order to replace the petroleum-based fuels by several types of less polluting fuels, such as blends of diesel oil with vegetable oil esters and diesel fuel with vegetable oils and alcohol, emulsions, and also microemulsions. The main objective of this work was the development of microemulsion systems using nonionic surfactants that belong to the Nonylphenols ethoxylated group and Lauric ethoxylated alcohol group, ethanol/diesel blends, and diesel/biodiesel blends for use in diesel engines. First, in order to select the microemulsion systems, ternary phase diagrams of the used blends were obtained. The systems were composed by: nonionic surfactants, water as polar phase, and diesel fuel or diesel/biodiesel blends as apolar phase. The microemulsion systems and blends, which represent the studied fuels, were characterized by density, viscosity, cetane number and flash point. It was also evaluated the effect of temperature in the stability of microemulsion systems, the performance of the engine, and the emissions of carbon monoxide, nitrogen oxides, unburned hydrocarbons, and smoke for all studied blends. Tests of specific fuel consumption as a function of engine power were accomplished in a cycle diesel engine on a dynamometer bench and the emissions were evaluated using a GreenLine 8000 analyzer. The obtained results showed a slight increase in fuel consumption when microemulsion systems and diesel/biodiesel blends were burned, but it was observed a reduction in the emission of nitrogen oxides, unburned hydrocarbons, smoke index and f sulfur oxides