Orientador: Ulisses Rocha Antuniassi / Banca: Kléber Pereira Lanças / Banca: Rone Batista de Oliveira / Resumo: O objetivo do presente trabalho foi determinar a velocidade das gotas geradas por uma ponta de jato plano de faixa ampliada (XR11003) em função de variações na tensão superficial e da viscosidade de caldas compostas por diluições de um surfactante e um óleo vegetal. Os adjuvantes utilizados foram o surfactante Agral e o óleo vegetal Natur'óleo, além de uma calda padrão (testemunha) composta apenas por água. Os ensaios foram conduzidos em delineamento inteiramente casualizado com 5 repetições. Para isso foram determinadas as viscosidades e tensão superficial para diferentes concentrações dos adjuvantes, bem como velocidade de gotas. As caldas pulverizadas foram amostradas em condições operacionais idênticas de pressão (2,8 bar), buscando a quantificação das velocidades de forma homogênea, em diferentes diâmetros de gota: 50, 100, 150, 200, 250, 300 e 350 µm. Os experimentos foram conduzidos para coleta na altura de pulverização de 30 cm em relação ao analisador de partículas em tempo real VisiSize Portable (Oxford Lasers Ltd / UK). Foram ajustados modelos para os dados de velocidade e tamanho de gotas, viscosidade e tensão superficial, assim como realizou-se a Análise de Variância para significância do modelo e o coeficiente de determinação múltipla. A análise de correlação foi empregada para verificar o efeito da viscosidade e tensão superficial sobre a velocidade de gotas. Os resultados mostraram que os modelos tridimensionais indicam a formação de gradiente ascendente da ve... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The objective of the present work was to determine the velocity of the droplets generated by a wide band plane jet (XR11003) as a function of variations in surface tension and viscosity of syrups composed of dilutions of a surfactant and vegetable oil. The adjuvants used were the Agral surfactant and the Natur'óleo vegetable oil, besides a standard syringe (control) composed only of water. The trials were conducted in a completely randomized design with 5 replicates. For this, the viscosities and surface tension were determined for different concentrations of the adjuvants, as well as droplet velocity. The pulverized samples were sampled under identical operating pressure conditions (2.8 bar), aiming at the quantification of the homogeneous velocities in different drop diameters: 50, 100, 150, 200, 250, 300 and 350 μm. The experiments were conducted at the 30 cm spray height in relation to the VisiSize Portable (Oxford Lasers Ltd / UK) real-time particle analyzer. Models for the velocity and droplet size, viscosity and surface tension data were adjusted, as well as the Analysis of Variance for model significance and the multiple determination coefficient. Correlation analysis was used to verify the effect of viscosity and surface tension on the droplet velocity. The results showed that the three-dimensional models indicate the formation of an upward velocity gradient as a function of viscosity, that is, a trend of higher velocities was observed for higher viscosity values. The inverse occurred for surface tension (downward velocity gradient as a function of surface tension), that is, a trend of lower velocities was observed for higher values of surface tension. However, no significant correlations were observed between surface tension or viscosity and velocities for each droplet size (p> 0.05). It is concluded, therefore, that for the spray tip XR 11003 at a pressure of 2.8 bar, the droplet ... / Mestre

Made available in DSpace on 2014-06-11T19:22:16Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-11-23Bitstream added on 2014-06-13T20:28:24Z : No. of bitstreams: 1 vigano_lls_me_botfca.pdf: 315511 bytes, checksum: 1c704179aaf952553a743ea80191f02c (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O presente trabalho teve como objetivo avaliar o efeito da assistência de ar junto à barra de pulverização e três volumes de aplicação na dessecação e deposição da calda em arroz vermelho sob cultivo de nabo forrageiro em recuperação de áreas de várzeas, pulverizado com herbicida paraquat e corante azul brilhante, respectivamente. Os volumes de calda de pulverização foram 100, 200 e 300 L ha-1, da solução contendo corante alimentício (0,15%, p/v). Tanto na presença do ar junto à barra quanto na sua ausência foram utilizadas pontas de pulverização de jato plano tipo AXI 110015 a pressão de 117,3 kPa, AXI 11002 e AXI 11003 a pressão de 276 kPa. A avaliação da deposição da pulverização deu-se em folhas de plantas de arroz vermelho. Verificou-se nos resultados que houve diferença na deposição entre diferentes técnicas e volumes de calda testados nas plantas de arroz vermelho. Maior deposição foi alcançada pelo maior volume aplicado (300 L ha-1) com a assistência de ar junto à barra pulverizadora. Não se constatou diferença na deposição quando aplicados os volumes de 100, 200 e 300 L ha-1 sem assistência de ar e 200 e 300 L ha-1 com assistência de ar. As maiores porcentagens de dessecação de arroz vermelho foram constatadas com a aplicação de 300 L ha-1, tanto na presença quanto na ausência de assistência de ar junto à barra pulverizadora. / The aim of this research was to evaluate the effect of air-assistance on spraying at three volumes in the dessecation and deposition on red rice under fodder radish cultivation. To evaluate the dessecation and spray deposition were used paraquat herbicide and a Brilliant Blue dye, respectively. The three volumes of spray were 100, 200 and 300 L ha-1, using a tracer dye at 0,15% (w/v). Both solution used flat fan nozzles AXI 110015 at 117.3 kPa, AXI 11002 and AXI 11003 at 276 kPa. The evaluation of deposition was made on red rice leaves. We observed no significant different deposition between spray techniques and application volumes on red rice plants. Higher deposition was obtained by 300 L ha-1 application with air assistance in the spray boom. No difference it was observed on spray deposition at 100, 200 and 300 L ha-1 volumes without air assistance and at 200 as well as 300 L ha-1 with air assistance. The highest percentages of red rice dessecation were observed with 300 L ha-1 application with or without air assistance at the sleeve boom sprayer.

Orientador: Ulisses Rocha Antuniassi / Banca: Carolina Aparecida de Souza Queiroz / Banca: Paulo Roberto Arbex Silva / Resumo: O setor florestal brasileiro ocupa destaque no cenário mundial da cultura de florestas plantadas. A ampliação das áreas com florestas plantadas demandam desenvolvimento tecnológico e otimização de mão-de-obra. O uso da aviação está em franca expansão na atividade florestal. O presente trabalho teve o objetivo de definir qual a melhor combinação entre alturas de vôo e volumes de calda na aplicação aérea de herbicidas em área de implantação florestal por meio de análise de deposição das caldas. O experimento foi realizado em área de pastagem da Fazenda Morro Branco, situada no município de Porto Espiridião no Estado de Mato Grosso. O ensaio foi instalado com nove tratamentos que consistiram nas combinações de três volumes de calda (20, 30 e 50 L ha-1) e três alturas de vôo (10, 30 e 40 m). As aplicações foram realizadas utilizando-se uma Aeronave Air Tractor AT-802, equipada com barras contendo 54 bicos com pontas de jato plano ajustáveis. Os dados foram analisados inicialmente por meio de mapas para verificar a variabilidade espacial e tendência da distribuição pontual dos depósitos das caldas. Posteriormente foi realizada a análise comparativa dos tratamentos utilizando o método estatístico "Intervalo de Confiança para Diferenças entre as Médias" com grau de confiança de 95% (IC95%). Para a determinação dos depósitos de calda foi utilizado metodologia de cromatografia líquida de alta eficiência (HPLC) e para determinação de deriva foi utilizado balanço de massas. Em geral, houve tendência de aumento de depósitos de calda com a redução da altura de vôo, independente do volume aplicado. Os tratamentos com altura de vôo de 10 m apresentaram quantidades de depósitos superiores aos demais tratamentos, independente do volume de calda aplicado / Abstract: The Brazilian forestry sector takes a highlight position on the global forest plantations. Forestry plantation areas are in expansion and require technological development and workmanship optimization. The use of aviation technology is growing in forest areas. The aim of the study was to define the best combination of height flight and spray volume rates in aerial herbicides application in forestry establishment area by deposition analysis. The experiment was conducted in a pasture area at Morro Branco Farm, located in Porto Espiridiao City, Mato Grosso State. The test was set up with nine treatments, consisted of three spray volumes rates (20, 30 and 50 L ha-1) and three height flights (10, 30 and 40 m). The applications were performed by Aircraft Air Tractor AT-802, equipped with boom containing 54 nozzles with adjustable flat fan tips. Data were analyzed initially by using maps to determine the spatial distribution and trend of timely deposits of mixtures. Afterwards, for comparison between treatments, the statistical method "Confidence Intervals for Differences between Means" was used, with confidence level of 95%. Spray deposits was determinate by High Performance Liquid Chromatography (HPLC) and for drift determination was used mass balance. In general, there was a tendency to increase spray deposits by reducing flying height, regardless of the volume applied. The treatments with 10 m flying height had higher deposits amounts, regardless of spray volume rate / Mestre

O objetivo do trabalho foi o de comparar a eficiência de aplicação de agroquímicos na cultura da soja utilizando diferentes pontas de pulverização para aplicações terrestres em alta velocidade. Foram avaliadas as pontas AXI 110 04 na velocidade de 15 km.h-1 (testemunha), APE Cinza, AXI 110 08, TD Hispeed 110 06 e AXI TWIN 120 06, todos na velocidade de deslocamento de 35 km.h-1. O volume de aplicação foi fixado em 120 L.ha-1. A eficiência de aplicação foi avaliada por dois métodos: Análise do percentual de cobertura utilizando marcador fluorescente e luz ultravioleta e análise de depósito através da recuperação e quantificação do corante azul brilhante FD&C N°1 por espectrofotometria. Ambas as analises foram feitas em amostras retiradas de três partes da planta: Superior, média e inferior. As pontas de pulverização mostraram padrões de cobertura e depósito diferenciados, de modo que na parte superior da planta, a cobertura foi favorecida por gotas mais finas e o depósito melhorado pelo uso de gotas médias. Nas demais partes da planta não houve diferença estatística entre os tratamentos tanto para cobertura quanto para depósito. A velocidade de deslocamento não interferiu na eficiência de aplicação para pontas com mesmo padrão de gota, permitindo o aumento da capacidade efetiva do pulverizador sem diminuição na qualidade da aplicação. / The aim of this study was to compare the efficiency of agrochemical application on soybean crop using different types of spray nozzles for ground applications in high travel speed. It was evaluated the nozzles AXI 110 04 with ground speed of 15 km.h-1 (reference), APE Grey, AXI 110 08, TD Hispeed 110 06 and AXI TWIN 120 06, all using travel speed of 35 km.h-1. The volume rate was fixed in 120L.ha-1. The application efficiency was evaluated by two different methods: Analysis of coverage area using fluorescent dye tracer and UV light and analysis of deposits through the recovery and quantification of bright blue tracer FD&C N°1 by Spectrophotometry. Both analysis were done in samples collected from three parts of the plant: Top, medium and bottom. The spray nozzles showed differences in coverage and deposit pattern, so in the top of the plant, the coverage was increased with smaller droplets and the deposit was increased with medium droplets. In the other parts of the plant, there was no statistical difference between the treatments both for coverage and deposit. The travel speed did not influence the application efficiency for droplet with the same droplet pattern, so it is possible to increase the effective capacity of the sprayer without decreasing the application quality.

Student Number : 0110574V - MPh research report - School of Public Health - Faculty of Health Sciences / Pesticide poisoning poses a health risk to individuals throughout the world although the reported global and local risk are not consistent in the literature. Mpumalanga Province has areas of epidemic malaria. Spray teams, applying local insecticides to indoor surfaces operate just prior to the rainy season (October to May) to control malaria. The purpose of this cross sectional study was to compare prescribed safe handling and application practices of Mpumalanga malaria spray operators mixing and applying insecticides versus actual practices in the field. All members of the spray operating teams were included in the study. A tick list and questionnaire was utilized to observe field practices and enquire about reasons for non-compliance. Only 28% of all operators complied with prescribed safety practices and differences in compliance between mixing (38%) and application (36%) were marginal. Gloves, face shields and dust masks were not utilized as recommended and contributed to the highest levels of non-compliance. Compliance was found to be dependent on gender, age, years of experience, education level and employment status. The low compliance rate necessitates further investigation of the malaria programme occupational safety management system. All stakeholders need to be aware of the consequences of pesticide poisoning and collaborate in efforts to work towards prevention rather than cure.

Orientador: Renato de Mello Prado / Banca: Anelisa de Aquino Vidal Lacerda Soares / Banca: Jairo Osvaldo Cazetta / Resumo: A pulverização foliar de manganês (Mn) é amplamente utilizada em cultivos anuais dada a deficiência do micronutriente no solo. A adição de silício (Si) na calda com o Mn poderia favorecer aspectos fisiológicos e nutricionais e a produção de plantas de milho e sorgo. Objetivou-se avaliar os efeitos do Mn e Si fornecidos via pulverização foliar na nutrição foliar de plantas de milho e de sorgo sob deficiência de Mn. Foram desenvolvidos dois experimentos, um com a cultura do milho (experimento milho) em casa de vegetação e outro com a cultura do sorgo granífero (experimento sorgo) em sala climatizada. O experimento milho foi composto de arranjo fatorial 4x2, sendo concentrações de Mn 0,0; 0,29; 0,58 e 0,87 g L-1na ausência e presença de Si (0,476 g L-1de Si) aplicados via foliar no estágio V4 e V6.O experimento sorgo foi realizado em arranjo fatorial 4x2 com concentrações de Mn 0,0; 0,17; 0,34 e 0,51 g L-1 na ausência e presença de Si (0,476 g L-1de Si) aplicados via foliar no estágio V4 e V6. Em ambos os experimentos avaliaram-se variáveis fisiológicas e de produção de massa seca para verificar efeito do Si e Mn na nutrição das plantas. A pulverização foliar de Mn com adição de Si na calda incrementou o acúmulo do micronutriente, o índice relativo de clorofila, a eficiência quântica do FSII, a eficiência do uso da água e refletiu na produção de massa seca das plantas de milho e sorgo. A pulverização foliar de Mn com adição de Si na calda é viável para as plantas de milho e de ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Foliar spraying of manganese (Mn) is widely used in annual crops due to micronutrient deficiency in the soil. The addition of silicon (Si) in the application liquid with Mn could favor physiological and nutritional aspects and the production of maize and sorghum plants. The objective of this study was to evaluate the effects of Mn and Si supplied by foliar spraying on leaf nutrition of maize and sorghum plants under Mn deficiency. Two experiments were carried out, one with maize (corn experiment) in greenhouse and the other with sorghum (sorghum experiment) in climatized room. The corn experiment was composed of factorial arrangement 4x2, with concentrations of Mn 0,0; 0.29; 0.58 and 0.87 g L-1 in the absence and presence of Si (0.476 g L-1 of Si) applied via leaf in stage V4 and V6. The sorghum experiment was performed in a 4x2 factorial arrangement with concentrations of Mn 0,0; 0.17; 0.34 and 0.51 g L-1 in the absence and presence of Si (0.476 g L-1 of Si) applied via foliar in stage V4 and V6. In both experiments were evaluated the physiological and dry mass production variables to verify the effect of Si and Mn on plant nutrition. Foliar spraying of Mn with addition of Si in application liquid increased micronutrient accumulation, relative chlorophyll index, FSII quantum efficiency, water use efficiency, and reflected in the dry mass production of corn and sorghum plants. Foliar spraying of Mn with addition of Si in application liquid is viable for maize and sorghum ... (Complete abstract click electronic access below) / Mestre

Direct Methanol Fuel Cells (DMFC) provide an exciting alternative to current energy storage technologies for powering small portable electronic devices. For applications with sufficiently long durations of continuous operation, DMFC’s offer higher energy density, the ability to be refueled instead of recharged, and easier fuel handling and storage than devices that operate with hydrogen. At present, materials and manufacturing challenges impede performance and have prevented the entry of these devices to the marketplace. Higher-performing, cost-effective materials and efficient manufacturing processes are needed to enable the commercialization of DMFC. In a DMFC, the methanol-rich fuel stream and the oxidant are isolated from one another by a proton-conducting and electrically insulating membrane. Catalysts in the electrodes on either side of the Membrane Electrode Assembly (MEA) promote the two simultaneous half-reactions which allow the chemical energy carried in the fuel and oxidant to be converted directly into electricity. The goal of this research effort is to develop a continuous manufacturing process for the fabrication of effective DMFC MEAs. Based on the geometry of the electrode and materials used in the MEA, we propose a roll-to-roll process in which electrodes are coated onto a suitable substrate and subsequently assembled to form a MEA. Appropriate coating methods for electrode fabrication were identified by evaluating the requirements of continuous manufacturing processes; an appropriate set of these processes was then reduced to practice on a custom-designed flexible test bed designed explicitly for this project. After establishing baseline capabilities for several candidate methods, a spraying process was selected and a continuous manufacturing process concept was proposed. Finally, key control parameters of the spraying process were identified and their influence tested on actual MEAs to define optimal operating conditions. / text

No description available.

Rolling contact is experienced by a large number of components in mechanical designs. Examples include roller bearings and ink distribution rollers in the printing industry. Rolling contact results in surface wear. It is however possible to reduce rolling contact wear rates and surface fatigue by performing a surface modification such as powdered metal coating [35]. Powder coating methods such as Laser cladding and Plasma coating are two application processes that are completely different in method and therefore create different coating microstructures and bonding mechanisms between the coating and substrate. The aim of the research was to investigate the comparative rolling contact performance of two coating processes and two separate metal powder compositions. The coatings were applied to British standard En 9 steel test specimens. En 9 was selected due to its popular use in the manufacture of shafts, cylinders and rollers. Under rolling contact, material is removed from the surface as a result of wear and surface fatigue. Through testing and evaluation, the performance of the coating application processes were evaluated relative to one another and relative to the uncoated steel under rolling contact. The performance of the coating compositions were also evaluated against one another for a given coating application process. Results used to determine the performance of the coatings and coating processes were, the number of cycles to failure and the wear rates of the coated surface. Microstructure pictures of the coated surface were taken prior to testing and following testing. The pictures were used to qualitatively determine the effects of the rolling contact on the surfaces. Through the study of rolling contact, an explanation of the stresses induced in the contact area and the position of the maximum values were determined. The boundaries for the deformation regimes were identified through the understanding of the position of first yield and the shakedown limit under rolling contact. The theories of rolling contact fatigue are covered briefly as part of a better understanding of the failure mechanism however the experimentation is largely comparative based. / Thesis (M.Sc.)-University of KwaZulu-Natal, Durban, 2008.

Integrally heated composite tooling (IHCT) is seen as a low cost alternative to autoclave manufacturing of polymer matrix composites (PMCs). IHCTs consist of a composite tool heated by surface heaters; temperature distribution is ensured by a thermally conductive metallic layer. The main original contributions of this thesis was the development of a new method for applying copper coatings onto carbon fibre/epoxy PMCs using pulsed gas dynamic spraying, the production of larger size samples, and the characterisation of the performance of the coatings and laminates obtained. It was shown that this method has potential for producing the thermally conductive layer in an IHCT. Another contribution was the characterisation of parameters affecting temperature distribution across IHCTs through heat transfer simulations, leading to guidelines for IHCT design.