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Produção intelectual sobre educação no período ditatorial : uma análise a partir de textos publicados na SciELO
(Universidade Federal de São Carlos, 2017-03-03) Viana, Thais de Biagi; Buffa, Ester; https://lattes.cnpq.br/8723354256930377; https://lattes.cnpq.br/3952829590531344
This research had as general objective to enable a mapping of texts on education in the period of civil-military dictatorship, published in SCIELO database in the period between 1985 and 2016, publication dates of the first and last text located. The methodological procedures were performed by bibliometric approach, focused on documentary research, with a descriptive and exploratory character. Based on professional literature, the data were analyzed and presented in order to facilitate the identification of the following: geographic and institutional distribution of localized journals; recurrent authors; institutional origin of the authors and their participation in research groups; themes addressed in the texts; and which aspects were addressed in the texts that are included in the thematic axis "educational policy". It is understood that the results of the search will enable contributions to the History of Education, because besides the historical review and mapping of knowledge that is being produced on an extremely relevant theme to the educational field, it allows the dialogue with the current educational conditions, such as wage squeeze, poor structure of teacher training courses, close link between education and the labor market, fundaments of school management, valuation of private initiatives, etc.
Deformação plástica severa da liga Ti-13Nb-13Zr
(Universidade Federal de São Carlos, 2017-03-03) Pérez, Diego Alfonso Godoy; Jorge Júnior, Alberto Moreira; https://lattes.cnpq.br/6360362248108490; Botta Filho, Walter José; https://lattes.cnpq.br/8956458007749112; https://lattes.cnpq.br/8941716347276124
Biomedical devices currently in use (prostheses, implants) have satisfactory performance in many cases. However, sometimes the body reacts to the device insertion and may lead to its rapid replacement. Some of these disadvantages can be solved by the use of titanium and its alloys, due to their excellent combination of corrosion resistance, wear resistance and biocompatibility compared to other competing biomaterials. This work presents the possibility of obtaining near β titanium alloy with ultrafine grains produced by severe plastic deformation. For this, the Ti-13Nb-13Zr alloy was processed by high-pressure torsion processing method. Samples were processed with different loads and number of turns. The samples were evaluated by Vickers microhardness. As-received and deformed samples were analyzed through X-Ray diffraction. The microstructures were observed by optical microscopy and scanning electron microscope and the microtexture and phase mappings of the material evaluated through the ASTAR equipment in the transmission electron microscope. After characterization, it was observed that there is a refinement of the microstructure and increase of the microhardness of the Ti-13Nb-13Zr alloy deformed by HPT. Due to the superior microhardness of the deformed material and the results of phase transformations indicate a potential application as nanostructured biomaterial.
Síntese e Caracterização do Poli(PCL-TMC)uretana para utilização como Biomaterial
(Universidade Federal de São Carlos, 2017-03-03) Gomes, Rodrigo Cesar; Komatsu, Daniel; https://lattes.cnpq.br/2620060426867863; Duek, Eliana Aparecida de Rezende; https://lattes.cnpq.br/4147198882685212; https://lattes.cnpq.br/9974151176548878
Among the polymers widely investigated as materials for tissue engineering, polyurethane has its place of prominence, mainly due to the high flexibility and tenacity. The need for devices with certain mechanical properties combined with the ability to be biodegradable and bioreabsorbable motivates the scientific community to increasingly seek the creation of new materials in order to minimize the discomforts and increase the quality of life of the population. The present work aimed to synthesize a new copolymer produced from PCL and TMC with creation of urethane groups in the polymer chain. This synthesis combined the mechanical properties present in Polyurethane and PCL, with the increase of the modulus of elasticity conferred by the TMC, and allowed the increase of the degradation rate of the polyurethane due to the TMC. Prepolymer synthesis occurred in the bulk polymerization between PCL diol and TMC at 50/50 mass ratio using SnOct2 as catalyst. This synthesis was confirmed by FTIR and 1H NMR. The GPC analysis of three samples of the prepolymer showed Mn approximately 6000 g.mol-1 and Mw 12000 g.mol-1 with the IP close to 2. The poly (PCL-TMC) urethane formation occurred via solution polymerization between the prepolymer and HDI using solvent 1,2-dichloroethane and the molar ratio of 1: 2 (prepolymer / HDI). This synthesis was confirmed by FTIR and 1H NMR. Thermal characterization was performed using the DSC and TG techniques. There were no melt and crystallization temperatures in the DSC curve, indicating that the copolymer formed is probably amorphous, and the Tg found was -40 ° C. The TG indicated Tonset and Td, respectively 285 ° C and 301 ° C. Porous were made into the copolymer through solution freeze-drying and SEM test was performed on the porous material, and a mean pore diameter of approximately 38 μm was found, indicating the possibility of cell growth. Therefore, a new copolymer with potential application in biomaterials was created.
Efeitos da gramínea invasora Urochloa Decumbens Stapf (Poaceae) sobre a seleção do habitat de nidificação do Atobá-pardo (Sula Leucogaster, 1783) na Ilha do Castilho, Brasil
(Universidade Federal de São Carlos, 2017-03-03) Almeida, Gabriela Godinho de; Silva, Talita Ariela Sampaio; https://lattes.cnpq.br/1292408753626328; Matos, Dalva Maria da Silva; https://lattes.cnpq.br/4728734263109138; https://lattes.cnpq.br/6659707243400582
Biological invasion is listed among the major threats to native biodiversity, causing several impacts. In cases of invasion by exotic plants, vegetation composition and structure are usually changed. These characteristics influence directly on nesting habitat selection by birds at different spatial scales, and may affect their distribution and reproductive success. In this study, we investigated the interference of Urochloa decumbens Stapf., an aggressive invasive grass and which has a rapid proliferation, on nest-habitat selection by the brown-booby (Sula leucogaster Boddaert, 1783) in a Brazilian oceanic island, Castilho Island. At macroscale, the use of available invaded areas and native vegetation areas for nesting were compared. For microscale, different vegetation parameters were estimated 1 m around the nests in plots within invaded and native areas. The difference on the number of nests and vegetation parameters between invaded and native plots was tested. Lastly, the relationship between the number of nests per plot and vegetation parameters was evaluated through the construction of mixed-models. It was found rejection of invaded areas for nesting and preference for areas of native vegetation at macroscale. Plots in invaded areas had a significant lower number of nests, lower coverage proportion by native grasses and herbaceous cover, higher coverage proportion by U. decumbens and higher height of vegetation than native plots. At the microscale, the coverage proportion by invasive grass was the main variable affecting the choice, being negatively associated to the nest-site. Results indicate the importance of controlling U. decumbens to ensure the availability of appropriate nesting habitats for this seabird species.
Solidificação da liga de alumínio 319 conformada por spray
(Universidade Federal de São Carlos, 2017-03-03) Otani, Lucas Barcelos; Zepon, Guilherme; https://lattes.cnpq.br/7924187202036614; Bolfarini, Claudemiro; https://lattes.cnpq.br/9231627080617037; https://lattes.cnpq.br/2519980413159984
The main application of 319 aluminum alloy is for manufacturing components for automobile industry. One of the main concerns related to the recycling of this metal is regarding the incorporation of impurities as iron, for instance. Due to its low solubility in solid aluminum, the presence of this element leads to the formation of intermetallic compounds such as α-Al8Fe2Si and β-Al9Fe2Si2, the most common iron phases in Si-containing Al-alloys. The β phase is harmful to mechanical properties because of its platelet like morphology. Spray forming is an advanced processing technique which can mitigate the deleterious effect of these intermetallic phases. However, the solidification process of spray formed metals is still an open discussion. In these sense, the aim of this work is to contribute to a better understanding of the solidification process of spray formed 319 aluminum alloy. The work was divided in three stages: the first evaluated the presence and morphology of intermetallic phases by varying the pouring temperature and Fe content (0.6 and 1.2 in mass percent); the second evaluated the eutectic Al-Si morphology through varying the processing conditions; and finally, the third evaluated the solute distribution in the final microstructure, in this case other aluminum alloys were studied together with the 319 (2024 and 7050). The basis for discussion the phenomena was a solidification model for spray formed metals recently proposed in the literature, which defines the process in two stages, being the final solidification occurring at low cooling rate. The results showed that by controlling the processing parameters it is possible to mitigate the β-Al9Fe2Si2 formation, as well as to alter the eutectic Al-Si morphology. The third stage indicated the possibility of maintenance of certain solute in solid solution on the periphery of aluminum grains. It could be concluded that the solidification model was adequate to explain the phenomena presented in this work.
Técnicas de difração de elétrons e de caracterizações elétricas e térmicas combinadas para análise de transformações de simetria em estruturas perovskitas distorcidas : caso das soluções sólidas (Pb1-xCax)TiO3
(Universidade Federal de São Carlos, 2017-03-03) Estrada, Flávia Regina; Garcia, Ducinei; https://lattes.cnpq.br/5236758856687873; https://lattes.cnpq.br/3846613292162032
The main objective of this work was the unequivocally determination of the crystal symmetry of distorted perovskite structure by direct and indirect methods, with the solid solution system Pb1-xCaxTiO3 (PCT) as the case study. Therefore, ferroelectric ceramic of PCT were investigated using electron diffraction techniques, electric characterization and thermal expansion measurements at compounds with controversial results in the literature about its crystallographic symmetries and polar states, mainly in the Morphotropic Phase Boundary (MPB). Qualitative analysis of synchrotron X-ray diffraction pattern from PCT powders confirms that the octahedral tilting distortions exist from the calcium concentration x = 0.40. From this result, based on subgroup relations analysis and considering only the point group 2mm as a maximal subgroup (as a suit of the system), the symmetries Pna21 e Pcm21 were predetermined as common subgroups of the known space groups of the ending phases (P4mm, Pbnm, I4/mcm e Pm-3m). In turn, from the thermal expansion measurements and electric characterization, using thermal dependence of the dielectric permittivity and the polarization vs. electric field curves, some possibilities of crystallographic phase transition were determined, as well as the evaluation of the polar characteristics. To determine the tilt system and the crystal symmetry at room temperature, the electron diffraction techniques were used. The composition choice was 47.5 mol % of Ca, which represent a challenge in PCT MPB. The tilt system determined is the same of CaTiO3, the mix of antiphase and in phase tilt a-a-c+. Finally, combining results of the electron diffraction techniques set with the indirect techniques set, the orthorhombic symmetry with the point group 2mm and the space group Pna21 was found for the solid solution Pb0,525Ca0,475TiO3. This symmetry might cover other compositions in MPB at room temperatures. The results from the set of techniques protocol allowed concluding this symmetry and polar states from MPB phases as a function of temperature, adding new contribution to elucidate the PCT phase diagram.