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Sensibilidade de três variedades de cana-de-açúcar (Saccharum spp.) ao alumínio em solução avaliada por corantes indicadores
(Universidade Federal de São Carlos, 2011-06-29) Malvestiti, Jacqueline Aparecida; Soares, Marcio Roberto; https://lattes.cnpq.br/6337462438517339; https://orcid.org/0000-0002-9543-6450; https://lattes.cnpq.br/4554213632240773; https://orcid.org/0000-0002-0085-6015
Brazil is the world's largest producer of sugarcane (Saccharum spp.). Its production is expanding in regions characterized by soils with low fertility and high acidity. The influence of Al toxicity on the development of the root system and on the interference of nutrient uptake has been presented as one of the main causes of the low productivity of many soils. The objectives of this study were: to evaluate the root development of sugarcane varieties RB855156, SP81 3250, and RB935744 in nutrient solution with different Al stress conditions (0, 70, 130, 380, 800, 1400, and 2000 μmol L-1); to examine morphological changes in sugarcane roots through optical microscopy; to verify the penetration of Al into the root tissue with the use of Al-complexing dyes; to test the efficiency of hematoxylin and pyrocatechol violet dyes as indicators of the presence of Al in root tissue. The experiment was conducted under laboratory conditions, in a completely randomized design, with four replications. The root growth rate results (cm day-1) were submitted to analysis of variance and compared by Tukey's test, at a 5% significance level. Morphological parameters of Al in root tissues, indicated by color, were explored in the form of images by photographic recording of observations under an optical microscope. Increasing the Al concentration in solution caused a decrease in the root elongation rate. The critical concentration of Al in solution, regardless of variety, according to statistical analysis was 1400 mmol Al L-1. The main morphological alterations of the roots were observed from the critical concentration of 800 mmol Al L-1 in solution, and include the production of callose and the collapse and deformation of the root cap. The hematoxylin dye was more efficient than pyrocatechol violet to indicate the accumulation and location of Al in the root tissue. The tolerance sequence of sugarcane varieties to Al in solution was RB935744 (late)>SP81-3250 (medium)>RB855156 (early), and this may be correlated with the cycle of the varieties.
Análise da influência das condições de processamento na morfologia e nas propriedades de blendas poliméricas PBT/ABS moldadas por injeção
(Universidade Federal de São Carlos, 2011-06-29) Cardinali, Daniel Albuquerque; Hage Júnior, Elias; https://lattes.cnpq.br/1240692926327687; https://lattes.cnpq.br/4102444414752905
A study on the correlation of blend morphology, properties, the injection molding process and manufacturing methods of polymeric blends constituted of PBT and ABS was proposed. Thus, uncompatibilized PBT/ABS blends have been prepared in a twin-screw extruder using different parameters of process, in order to obtain blends presenting distinct properties and, if possible, distinct morphologies. The extruded blends have been eventually submitted to the injection molding process for the evaluation of the influence of the injection molding process parameters on the morphology, thermal properties and mechanical properties, especially impact strength, of PBT/ABS blends. The following parameters of the injection molding process and its influence on the properties mentioned above have been studied: injection temperature, mold temperature, holding pressure and injection speed. The Design of Experiments approach has been used to arrange the full set of experiments and also to statistically analyze the results. The morphology of the extruded and injection molded blends has been investigated by Transmission Electron Microscopy, the mechanical properties by Izod impact strength tests and the degradation of the blends constituents has also been evaluated. The results have indicated that major differences on the impact strength of the samples can be achieved by only varying the injection molding parameters. Furthermore, mold temperature and injection speed have significantly affected the impact strength and the ductile-brittle transition temperature of the injection molded samples. Morphological analyses and degradation studies have suggested that the dispersion degree of the ABS disperse phase particles within the PBT matrix plays an essential role in determining the impact strength of the blends.
A presença dos antigos em tempos de conversão: etnografia dos Kaingang do oeste paulista
(Universidade Federal de São Carlos, 2011-06-29) Lourenço, Marília Sene de; Peggion, Edmundo Antonio; https://lattes.cnpq.br/9849805103860827; https://lattes.cnpq.br/2639771998853175
This thesis deals with many kinds of relations between the São Paulo Kaingang and the others: their neighbours Krenak and Terena, non Indians finally, with Otherness in its Christian shape. For they‟ve chosen to articulate within their sociability another language through which persons and collectives are differencitated Catholicism and the Revivalist Churches Assembleia de Deus and Congregação Cristã no Brasil. It seems that they differenciate themselves through an oppositional process. Religious groups, political factions and extended families‟ daily oppositions, as observed through fieldwork, are brought to this text. The Jê bibliography also helps to give a sociality background to the empiric data. Hence the concepts stability and change , used as tools for the understanding of Kaingang transformations. To become a relative or an ex-relative, catholic or revivalist, an allied or an enemy these are possibilities of social action formulated by a thought that seems to be surprised by the numerous ambiguities of its own oppositional procedure. Mainly, by the ambiguity of life and death: connected to their dead relatives (the ancients), but also running away from them, the Kaingang try to solve this dilemma by all means especially in their daily life, where part of this tentative resides in conversion to Christianity.
Gestão do conhecimento: uma análise do setor automobilístico a partir de fatores contextuais da organização
(Universidade Federal de São Carlos, 2011-06-29) Gonzalez, Rodrigo Valio Dominguez; Martins, Manoel Fernando; https://lattes.cnpq.br/3921504261628850
The latest models on Knowledge Management (KM) recognize four stages to their practice: acquisition, storage, distribution and use of knowledge that presents itself as tacit and explicit. The KM is characterized as a multidisciplinary discipline, involving aspects of technical and social order and due to the diversity of issues about this topic, it is essential to delimit their study. In this sense, the proposed delimitation for this research is social and coordination, involving the identification of contextual factors, developed internally in organizations that support the process of KM in automotive companies. These contextual factors are defined based on organizational aspects to enable the development of the four phases of the KM, especially the development of human resources, organizational culture, teamwork, organizational structure and the way how knowledge is developed and absorbed internally. This thesis also identifies groupings (clusters) composed of companies with similar characteristics as the development of these contextual factors, analyzing the implications of the clusters features for KM and for the use of knowledge. The automotive companies can be characterized as advanced for improvement and innovation processes, and thus the knowledge management is fundamental to the sustainability of these activities. To achieve this goal, this research uses a quantitative research method, based on a survey. Data analysis is performed using multivariate statistical techniques of factor analysis, cluster analysis and discriminant analysis. In regarding the results were collected eight contextual factors that support the process of GC, and also identified four clusters for the development of these factors: innovate, exploited, exploited and Laggards. The companies of the first two groups have a better capacity to absorb knowledge and build a broader base of primary knowledge, making them more innovative, and the other two groups take a more reactive posture within the industry, following the development proposed by the companies of first two clusters. In the latter two groups, in particular exploited, there is the development of factors related to incremental improvement and teamwork, showing a tendency to use the knowledge designed to improve production efficiency.
Transposição e fragmentação do Rio Piumhi (Bacia do Rio São Francisco, MG): variáveis limnológicas e microcrustáceos zooplanctônicos da Lagoa dos Tropeiros
(Universidade Federal de São Carlos, 2011-06-29) Sonoda, Sérgio Luiz; Rocha, Odete; https://lattes.cnpq.br/7577441794992601; https://lattes.cnpq.br/6959066930874462
The aim of this study was to analyse the physical and chemical characteristics of Tropeiros Lake (Capitólio, MG), located in Piumhi river sub‐basin, a river diverted from the Rio Grande basin to the são Francisco River basin, and to analize the taxonomic composition, abundance, diversity and the size structure of the planktonic microcrustaceans. Physical and chemical variables in the eater were measured in situ by the multiparameter Horiba U10 probe and qualitative and quantitative zooplankton sampling was carried out in both, pelagic and littoral regions of this lake using the plankton net of 69 μm mesh size, on March, 2007. Twenty seven taxa were identified, being 18 Cladocera, 3 Copepoda Calanoida and 6 Copepoda Cyclopoida. Microcrustaceans species composition in Lagoa dos Tropeiros was much more similar to the microcrustaceans composition of the water bodies from Rio Grande basin than to those from São francisco basin. The species Sarsilatona serricauda Sars, 1901 and Microcyclops alius Kiefer, 1935 constitute new records for the state of Minas Gerais biota. The assemblages from of microcrustaceans from the littoral region had higher richness of species, higher alfa diversity, and wider size spectra than the assemblages from the pelagic region. The analysis of the normalized size spectra and linear regression analysis indicated that Lagoa dos Tropeiros has a community away from the stationary state. The accumulated curves of numerical abundance and biomass (ABC curves) were different for the lake regions characterizing the pelagic region as a non‐disturbed compartment and the littoral region as a disturbed system. The gamma parameter derived from rank‐abundance diagram slopes characterized the microcrustacean assemblage of Lagoa dos Tropeiros as typical of a low trophic state environment.
Reforma a vapor do metano sobre catalisadores de Pt-Ni/α-Al2O3: efeito das condições de síntese e do teor da Pt nas propriedades de oxi-redução, estruturais e catalíticas
(Universidade Federal de São Carlos, 2011-06-29) Souza, Vivian Passos de; Bueno, José Maria Corrêa; https://lattes.cnpq.br/0157452280626031; https://lattes.cnpq.br/5144435443949445
In recent years, the demand for hydrogen has increased considerably in Petrobras refineries, due to the installation of fuel hydrotreating units. These units are necessary to meet new quality standards, which are imposed by environmental concerns. Steam reforming is the most common process to produce hydrogen and synthesis gas. The catalyst used in this process has nickel as the active phase, supported in refractory material, such as alpha-alumina. These catalysts are most cost-effective, when compared to others with higher activity. On the other hand, the promotion of them with small amounts of noble metal can provide interesting characteristics, without greatly affecting their final cost. The catalyst at the top of the reformer is easily oxidized, either during unplanned shutdowns, or even during normal operation, if hydrogen is absent. The use of Pt as a promoter has been studied in the literature, and the results show its effect in decreasing the reduction temperature of nickel catalysts. Additionally, the catalysts at the top of the reformer (20-40%) are more prone to coking. The objective of this study is to evaluate how preparation conditions and platinum content affect the Ni/α-Al2O3 catalysts, regarding reduction and oxidation of the catalysts, and also their activity, stability and coke formation. The catalysts were evaluated under conditions which are characteristic of the top region of an industrial reformer. The catalysts were prepared with different contents of platinum, 0.01% and 0.3% wt, at different calcination temperatures after impregnation of nickel and platinum . It was observed that Pt increases the reducibility of catalysts with 10% wt of Pt, calcined at 600 and 800°C, as long as the final catalyst, after Pt impregnation, was calcined at low temperature. At higher temperatures, sintering of Pt takes place, suppressing its effect. An increase of calcination temperature of the NiO/α-Al2O3 catalyst from 600 to 800°C does not cause a considerable decrease of the Pt effect on the reduction. When the NiO/α-Al2O3 catalyst was calcined at 1000°C, the effect of Pt became insignificant. The Pt increases the reducibility of the catalyst even at levels as low as 0.01%wt, although its effect is greater when a higher content is used. This behavior is observed for the reduction, using H2 as well as H2 + H2O (v) or CH4 + H2O (v). The reduction with methane and steam occurs at higher temperature, but faster. In this case, it is assumed that as the Ni° atoms are generated at short distances from each other, diffusion over the support surface is easier, enhancing their nucleation into nickel metal clusters. The presence of Pt also minimizes the formation of species with greater support interaction, even when the final catalyst is subjected to oxidation at high temperatures (900°C). The promotion with 0.3% wt of Pt minimizes coke formation. This behavior is attributed to changes in the surface structure of the catalyst or in the reaction rate of coke formation. Apparently, for the catalyst with 0.01% wt of Pt, this small amount of Pt would be insufficient to cause any structural changes or variation in the rate of coke formation. This behavior was found in tests under conditions that enhance coke formation and also under normal conditions of catalytic evaluation. The catalytic evaluation including a reduction step with H2 and CH4 + H2O (v) and the thermogravimetric analysis for assessment of coke formation,demonstrated that the promotion with platinum leads to a greater activity of the nickel catalyst in the catalytic systems or test conditions where reducing the catalyst and/or the ability to keep it in the reduced state is a determinant factor.
Efeitos da iluminação-LED (850 nm) associada ao treinamento em esteira ergométrica em mulheres na pósmenopausa
(Universidade Federal de São Carlos, 2011-06-29) Paolillo, Fernanda Rossi; Bagnato, Vanderlei Salvador; https://lattes.cnpq.br/4947860249518663; https://lattes.cnpq.br/2081685444894225
The objective of this study was to investigate the effects of infrared-LED illumination associated with treadmill training. Forty five postmenopausal women (50-60 years old) participated in this study. They were randomly separated into 3 groups: (i) the LED group, with phototherapy during the treadmill training; (ii) the exercise group, carried out only treadmill training and (iii) the sedentary group, with neither phototherapy nor physical exercise. The treadmill training consisted of walking twice a week for 45 min at intensities between 85% to 90% maximal heart rate during 1 year. The irradiation parameters were 100mW, 40 mW/cm2, 108 J/cm2 and the treatment time of 45 min. The treatment was evaluated through maximal effort testing using treadmill, isokinetic dynamometry, anthropometry, body composition, blood exams, quality of life, bone mineral density, thermography, photographic documentation and nutritional aspects. The two-way ANOVA and one-way ANOVA with Bonferroni adjustments were used for the statistical analysis. The significance level was set at p<0.05. The most important results for the LED group were: improving the maximal exercise tolerance (ΔTlim=432±180seg, p=0.001 e; ΔMETs=4.2±1, p=0.01), increasing the muscle power (Δ=21±6W, p=0.04) and reducing fatigue (Δ=-7±4%, p=0.006). There were no significant differences in the body composition (p≥0.05), but a qualitative difference of the skin was seen concerning the treatment of cellulite. There were reducted cholesterol levels (Δtotal cholesterol=-42±23 mg/dl, p=0.0003 and ΔLDL=-35±20 mg/dl, p=0.001), as well as an increase of the quality of life (from 82±17 to 89±17, p=0.04). There were no significant differences noted concerning the bone mass loss (p≥0.05). The cutaneous temperature increased during the exercise with the LEDs (from 33.5±0.8°C to 34.6±0.9°C, p=0.03). The results showed that the LED-illumination (850nm) improved physical performance and showed clinical benefits for the group of women investigated. Phototherapy associated with treadmill training can therefore be potentially used for sports, rehabilitation and aesthetics protocols to achieve certain positive results.