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Influência térmica das configurações urbanas ao longo do eixo do Córrego Canela na cidade de São José do Rio Preto
(Universidade Federal de São Carlos, 2011-02-08) Rocha, Luciani Maria Vieira; Souza, Lea Cristina Lucas de; https://lattes.cnpq.br/0083847008256434; https://lattes.cnpq.br/2665625897264868
This research intends to investigate the influence of urban morphology in air temperature along the axis of Alberto Andaló Ave. and José Munia Ave., which border the Canela Stream in São José do Rio Preto. Initially, a review was made on the relationship between urban design and the influence of climate and vegetation on climate. Alongside, it was made a review of some existing studies on the expansion of the city, as well as on the occupation of streams margins by avenues construction. The cadastral and morphological data such as land use, topography, configuration of city blocks and lots, height of buildings and ground cover were surveyed in maps, either developed by the Municipality or obtained from satellite imagery and field observation. In order to collect temperature data, four points were chosen - two in José Munia Avenue and two in Alberto Andaló Avenue. The results of that field campaign at two measurement periods - the first in April and the second in July and August - revealed differences in the air temperature among the two avenues. The correlation of these data with the characteristics of land use and occupation showed a significant decrease of air temperature during the night due to the presence of vegetation and soil permeability, thus, minimizing the heat islands. Also, it was found that areas with high occupancy of buildings and intensely paved areas and city blocks lost less heat, leading to the formation of the highest heat islands during the night period.
Estudo comparativo das tensões na interface de compósitos de resina epóxi reforçados com fibras de carbono, aramida e vidro.
(Universidade Federal de São Carlos, 2011-02-08) Nossa, Tamires de Souza; Carvalho, Antonio José Felix de; https://lattes.cnpq.br/5050955206618507; Rubert, José Benaque; https://lattes.cnpq.br/1726311467903505; https://lattes.cnpq.br/9207946428944653; Paiva, Jane Maria Faulstich de; http://lattes.cnpq.br/7926832511513537; Tarpani, José Ricardo; http://lattes.cnpq.br/7107225405958690
Currently, composite materials are being used in several areas in substitution of some metallic alloys regarding to its superior properties and greater project flexibility. Therefore, synthetic fibers reinforced epoxy resin has some mechanical properties limited by its interface due to the interaction between fiber and matrix. The present research studies the interaction between the materials at the interface, considering the resin interaction with the three most employed composites fiber: carbon fiber, Aramida (Kevlar) and glass fiber (E type). The fibers surfaces were analyzed through the AFM (atomic force microscope) and the Contact Angle Method (CAM), becoming possible to determine the surface energy of each material, the superficial interface energy, the matrix-fiber adhesion and the surface profile analysis. The composites were subjected to the single fiber fragmentation test (SFFT) in order to obtain its interfacial share strength to be applied in the Kelly-Tyson equation. Furthermore, through these analysis became possible to evidence the properties differences between the composites, the individual properties of matrix-fiber that can be obtained, the best matrix-fiber interface, classifying them according to the stress transference magnitude and, consequently, greater effectiveness on the matrix-fiber adhesion.
Estudo da compactação de resíduos lignocelulósicos para utilização como combustível sólido
(Universidade Federal de São Carlos, 2011-02-08) Chrisostomo, Walbert; Botaro, Vagner Roberto; https://lattes.cnpq.br/2907189124654066; Yamaji, Fábio Minoru; https://lattes.cnpq.br/4787449634914831; https://lattes.cnpq.br/4847981299225705; De, Antonio José Felix Carvalho; http://lattes.cnpq.br/5050955206618507; Caraschi, José Cláudio; http://lattes.cnpq.br/5729302235544407
The production of energy from the combustion of lignocellulosic materials is an interesting way to waste recovery. Two main factors hampering the use of these residues as fuel are the low density and the high moisture content. Compression of lignocellulosic residues can be a way of producing solid fuel of better quality. The aim of this study was to evaluate the quality of solid fuels (briquettes) produced from the compaction of waste generated in lignocellulosic agroindustrial processes. The materials used in this study were: sugar cane bagasse, sawdust of Eucalyptus sp and sawdust of Pinus sp. The residues were compressed under the same conditions of particle size (particle size ranging from 20 to 40 mesh) and moisture content (10% dry basis). The compression was performed in a hydraulic press, without heating. The compaction pressure used was 1250 kgf.cm-2 and the time of application of the maximum load was 15 seconds. The production of briquettes was possible with the three types of materials used. The briquettes produced had densities ranging between 840 and 872 kg.m-3. This represented a volume decrease of 12.2 times for the sugar cane bagasse, 6.01 times for the eucalyptus and 5.28 times for the pine. The longitudinal expansion of the briquettes was 9.44% for the eucalyptus, 9.61% for the sugarcane and 10.76% for the pine. The results of diametral compression test were 1.01 MPa (eucalyptus), 0.61 MPa (cane) and 0.45 MPa (pine). The higher heating values (HHV) found were 4675 kcal.kg-1 (pine), 4436 kcal.kg-1 (eucalyptus) and 4138 kcal.kg-1 (cane). The results showed that all the materials tested can be used in the production of briquettes and the production of briquettes was possible by compression without heating. The compacting process improved the quality of solid biofuel.
Estudo das propriedades ópticas e morfológicas de pós de SrMoO4 processados em sistemas hidrotérmicos
(Universidade Federal de São Carlos, 2011-02-08) Sczancoski, Júlio César; Longo, Elson; https://lattes.cnpq.br/9848311210578810; https://lattes.cnpq.br/3260698029458172
In the last years, the luminescent emissions of SrMoO4 have been investigated for technological applications in solid-state lasers, light emission diodes, cell phone displays and lamps. In terms of synthesis routes, the hydrothermal systems have received special attention of the scientific community because of the versatility in the formation and crystallization processes of ceramic oxides at low temperature conditions (from 100 °C to 250 °C). Besides the reduced costs and environmentally friendlies, these methods are able to allow a control on the morphologies and particle sizes. Hence, in this research, SrMoO4 powders were synthesized by the co-precipitation reaction and processed in conventional and microwave-hydrothermal systems at 140 °C for 2 h. Thus, it was analyzed the influence of the hydrothermal conditions and the different strontium precursors on the optical and morphological properties of these powders. As experimental results, the X-ray diffraction patterns and the Raman-active vibration modes proved that all powders have a scheelite-type tetragonal structure. Diffraction peaks associated to the secondary phases were only identified in the samples prepared with strontium carbonate. The Rietveld refinements suggested the existence of distortions on both [SrO8] and [MoO4] clusters. The typical bending symmetric and stretching anti-symmetric modes between the O-Mo-O bonds were detected by the infrared spectroscopy. The field-emission gun scanning electron microscopy images revealed that the distinct strontium precursors as well as the hydrothermal conditions were able to change the microcrystal shapes. The adsorption/desorption isotherms showed profiles of type IV with hysteresis curves similar to the H3, suggesting the predominance of slit-like vacant spaces between the particles. The ultravioletvisible absorption spectra indicated the presence of intermediary energy levels within the band gap, which are arising from structural defects in the materials. xvi When excited with 350 nm wavelengths, all samples exhibited broad band photoluminescence emissions. Moreover, the profiles of these spectra were influenced by the precursors and/or hydrothermal treatments.