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Propriedades mecânicas das ligas Ti34Cu36Ni8Zr22 e (TiZr)80Co12Fe8
(Universidade Federal de São Carlos, 2012-03-23) Medeiros, Marcia Moreira; Bolfarini, Claudemiro; https://lattes.cnpq.br/9231627080617037; https://lattes.cnpq.br/8260391121543962
Bulk amorphous and nanocrystalline alloys have attracted great interest from the scientific community. Titanium based alloys have demonstrated potential for formation of amorphous. This study aimed at to evaluate the mechanical properties of the Ti34Cu36Ni8Zr22 and (TiZr)80Co12Fe8 alloys, at room temperature. Thereby, nanoindentation, compression and three points bending tests were performed. The methodology involved the following steps: (i) production of alloys by arc melting under argon atmosphere, (ii) production of amorphous ribbon by melt-spinning, (iii) heat treatment of the ribbons at different temperatures, (iv) production of test specimens through casting in copper chill followed by quenching (v) microstructural characterization via scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDS), transmission electron microscopy (TEM), differential scanning calorimetry (DSC) and X-ray diffraction (XRD), (vi) mechanical characterization based on nanoindentation, compression and torsion tests. The results of nanoindentation showed an increase in hardness and reduced Young's modulus as the temperature of the heat treatment approachs the crystallization temperature. Results of compression and bending showed strong dependence on the preparation surface and internal defects of the specimens. The Young's modules and tensile strengths are below those reported in the literature, probably due to internal defects present in the samples such as pores.
Falas Waikhana: conhecimento e transformações no alto rio Negro (rio Papuri)
(Universidade Federal de São Carlos, 2012-03-23) Silva, Aline Scolfaro Caetano da; Andrello, Geraldo Luciano; https://lattes.cnpq.br/5447074379881029; https://lattes.cnpq.br/9307937859005364
Result of an ethnographic research among the Waikhana (Pira-Tapuia), a Tukanoan group that lives around the Uaupes basin, Amazonian Northwest, this dissertation focuses on hierarchy and circulation of knowledge in Uaupes contemporary context. This context is characterized by what has been called by the indigenous groups as culture recovery and revitalization movement . Involved in this local dynamics, the Waikhana attempt to recover by one side some ritual practices and traditional techniques of environment handling and by the other side the written record of certain oral knowledge in former times updated and transacted in ritual occasions. Trying to understand the way the indigenous are experiencing those processes and emphasizing their developments in the sphere of their own sociopolitical relations, this text approaches some classical themes on regional literature concerning social organization and cosmology. Some interpretations and redirections made by the indigenous themselves, concerning the problematic of hierarchy and circulation of knowledge will be presented. And will show that these interpretations and redirections bring some relations and positions of a Waikhana (cosmos) politics up to date.
Estudos das relações estrutura-toxicidade de agrotóxicos
(Universidade Federal de São Carlos, 2012-03-23) Kurohane, Cesar Augusto; Montanari, Carlos Alberto; https://lattes.cnpq.br/9200533791228786; https://lattes.cnpq.br/8340874473138451
Computational methods such as electrostatic and structural similarity of compounds were used to determine a similarity pattern for pesticides present in the database of the Medicinal Chemistry Group IQSC/USP. A collection consisting of herbicides and insecticides allowed and banned, according to the World Health Organization was used in this study. Several chemometric analyzes were performed to determine the recognition pattern processes in the classification of substances into their chemical classes that were associated with levels of 61-86% of correct prediction. Three case studies were carried out to validate the established hypotheses which showed good results in all cases. The disclosure of chemical space associated with the biological space using robust methods of analysis led to the establishment of rules for the selection and identification of patterns that can now be used as the foundation for the design of new herbicides and insecticides.
Uso de imagens digitais e ferramentas quimiométricas para identificação e determinação de Cr (VI) em solos contaminados
(Universidade Federal de São Carlos, 2012-03-23) Oliveira, Luciana Fontes de; Pereira Filho, Edenir Rodrigues; https://lattes.cnpq.br/3394181280355442; https://lattes.cnpq.br/1848439223921790
The determination of toxic metals in soils is an important factor to access their quality or identify possible contamination. The element Cr has double feature: Cr (III) is essential for human beings and Cr (VI) is toxic. In this context, the aim of this work is to propose a simple test for the determination of Cr (VI) in soil samples using digital images and chemometric tools. The samples used in this project were collected at Maritime Antarctica, around the Comandante Ferraz Antarctic Station (a Brazilian scientific station). Alkaline medium was used to extract Cr (VI) of the samples and the chromogenic reagent was added to color development. To obtain the digital images, the extracts were placed in Petri dishes and a multifunction printer was employed. The results were compared with those calculated by molecular absorption spectrometry. For the images, the MatLab program version R2009a was used to obtain the mean values of colors R, G, B, H, S, V, r, g, b and L, and the Pirouette 4.0 program to the chemometric tools application. The digital images were evaluated in order to be applied for the proposition of models of classification and supervised calibration method PLS (Partial Least Squares). Two types of preprocessing were used to calculate PLS models: autoscaled and mean centered. For the calibration set was used the blanks and standards in a total of 52 solutions and as validation set was used 44 solutions (samples replicas). The model using the mean centered preprocessing was better. Furthermore, when the real values were compared with the predicted the coefficient of correlation was 0,991. It is evident that the proposed method is a simple strategy with low cost for the detection of Cr (VI) in soil samples. Furthermore, the images have great potential to be applied for classification models. The Pb determination using digital images was also tested, but problems with the solutions pH did not permit the application of the methodology for real samples.
Estimação clássica e bayesiana para relação espécieárea com distribuições truncadas no zero
(Universidade Federal de São Carlos, 2012-03-23) Arrabal, Claude Thiago; Andrade Filho, Marinho Gomes de; https://lattes.cnpq.br/4126245980112687; https://lattes.cnpq.br/0235029522811813
In ecology, understanding the species-area relationship (SARs) are extremely important to determine species diversity. SARs are fundamental to assess the impact due to the destruction of natural habitats, creation of biodiversity maps, to determine the minimum area to preserve. In this study, the number of species is observed in different area sizes. These studies are referred in the literature through nonlinear models without assuming any distribution for the data. In this situation, it only makes sense to consider areas in which the counts of species are greater than zero. As the dependent variable is a count data, we assume that this variable comes from a known distribution for discrete data positive. In this paper, we used the zero truncated Poisson distribution (ZTP) and zero truncated Negative Binomial (ZTNB) to represent the probability distribution of the random variable species diversity number. To describe the relationship between species diversity and habitat, we consider nonlinear models with asymptotic behavior: Exponencial Negativo, Weibull, Logístico, Chapman-Richards, Gompertz e Beta. In this paper, we take a Bayesian approach to fit models. With the purpose of obtain the conditional distributions, we propose the use of latent variables to implement the Gibbs sampler. Introducing a comparative study through simulated data and will consider an application to a real data set.
Modificação das propriedades dos polímeros comerciais de SBR e NBR a partir da incorporação de nanopartículas sintéticas
(Universidade Federal de São Carlos, 2012-03-23) Arantes, Tatiane Moraes; Camargo, Emerson Rodrigues de; https://lattes.cnpq.br/7720754304065239; https://lattes.cnpq.br/9039822138866007
Numerous efforts have focused on the search for new materials involving lower cost, greater durability and, especially, lower environmental impact. In this sense, polymer nanocomposites have become the focus of many research groups because of their superior mechanical and thermal properties. In this work, nanocomposites of SBR and NBR with silica nanoparticles and synthetic clay Laponite, without and with the surface modification with silane 3-(trimethoxysilyl) propyl methacrylate (TMSPM), were prepared by means of simple mix of components using the colloidal route. The nanocomposites of SBR and NBR with Laponita showed exfoliated structure, with the presence of clay tactoids intercalated by the polymeric matrix, with homogeneity at the nanometric level and lower molecular mobility. The nanacomposites had increase in the thermal stability than the pure polymer and the mechanical properties showed a increase in storage modulus, loss modulus and damping properties (noise, vibration). Nanocomposites of SBR and NBR with Laponite functionalized with TMSPM also been prepared and presented structure intercaled with the presence of clays tactoids. There was a reduction in molecular mobility and increased in the glass transition temperature (Tg) with increase of the Laponite content. The silica nanoparticles were synthesized by controlled hydrolysis and condensation of tetraethyl orthosilicate (TEOS) in an alcoholic medium. In addition, silica nanoparticles are functionalized with TMSPM. The nanocomposites of SBR and NBR with silica nanoparticles with and without the surface functionalization were prepared by the colloidal route. Nanocomposites showed silica agglomerates in the form three-dimensional structure nanoparticles with and without modification in the SBR and NBR. The nanocomposites of SBR and NBR with silica showed a decrease in Tg, around 10 °C, increase in storage and loss modulus and damping properties with the increased amount of silica.
Características antropométricas e posturais de pés de idosos diabéticos e não diabéticos: evolução no período de quatro anos
(Universidade Federal de São Carlos, 2012-03-23) Aquino, Victor da Silva; Rebelatto, José Rubens; https://lattes.cnpq.br/1684247449456330; https://lattes.cnpq.br/0894735020809128
The aging of the population is a phenomena observed in the whole planet. Brazil follows this tendency with 21 million elderly, who correspond to 11,3% of the population. The projection is that in the year 2025 the population of elderly in Brazil will increase 16 times against five times the total population reaching, in absolute values, the sixth position in elderly population in the world. Close to 10 to 15% of the Brazilian population with age superior to 50 years has Diabetes Mellitus12. Due to the lack of studies which observed the behavior of anthropometric and postural measures in elderly diabetic in the long term, the objective of this paper was to investigate, in the period of 4 years, which anthropometric and postural alterations occur in the feet of elderly diabetic and, compare them with non-diabetic elderly. Four hundred and three individuals with 60 years of age or more were contacted, who participated of the study previous to 2006, of which 165 accepted to participate again. In this way, the current paper had four groups of participants, Diabetics 2006 (72), Diabetics 2010 (26), Non-Diabetics 2006 (331) and Non-Diabetics 2010 (139). All the participants answered an interview-questionnaire that contemplated social aspects, orthopedic investigation and the presence of pain. At the end of each evaluation the individual was invited to a re-evaluation after one week, with the purpose of verifying the trustworthiness of the measurements carried out by the same examiner at different moments. For the analysis of the anthropometric variables and of Arch Index, between the years 2006 and 2010, the groups were composed of 165 individuals, of which 26 were diabetic and 139 non-diabetic. On the other hand, for the Foot Posture Index IPP and its six criteria, groups of Diabetics were composed of 72 individuals in 2006 and 26 in 2010; and for comparison in the Non-diabetics, the 2006 group was composed of 331 individuals and the 2010 group of 139. The characterization of the sample was made by means of descriptive analysis, with central tendency and dispersion measures. Throughout 4 years, a reduction of the Length of the feet, reduction in the Height of the 1st Finger, of the Angle of the 1st Metatarsofalangeana Articulation was found between the Diabetics and Nondiabetics. There was also an increase in the Arch Index in the same period in both groups. In the comparison of the postural variables, the group of Non-diabetics changed more than the Diabetics group. The changes that occurred were, an increase of the percentage of neutral feet and a reduction in the alterations.
O mapeamento dos conflitos socioambientais de Mato Grosso: denunciando injustiças ambientais e anunciando táticas de resistência
(Universidade Federal de São Carlos, 2012-03-23) Silva, Michelle Tatiane Jaber da; Sato, Michele; https://lattes.cnpq.br/9264997837722900; https://lattes.cnpq.br/8921793262672558
The State of Mato Grosso-Brazil, locus of this research, is singular from the ecological point of view, encompassing three important biomes: Amazon, Cerrado (Savannah) and Pantanal, and also a peculiar ecosystem called Araguaia. However, in this landscape there is a contrast between the results of the search for economic growth strongly centred on the activities of the agribusiness, of the power plants and other activities that are the driving force of significant socio-environmental conflicts. These conflicts that emerge when at least one of the groups has the continuity of their ways of life threatened by undesirable environmental impacts, due to the action of other groups. The understanding of such a diverse dynamic that is present in this territory is emphasized in this research, since the main aim of this thesis is to map the main social environmental conflicts that are in the 12 planning regions of Mato Grosso, from the narratives of the vulnerable social groups. In this context, we consider that the vulnerable social groups are the most affected by this model and we presuppose that in places where the conflicts are more intense, the tactics of resistance and organized forms are also more expressive. So, in order to investigate such issues, we started in 2008 a research Project Mapping of identities and territories of the State of Mato Grosso , developed by the Environmental Education, Communication and Arts Research Group of the Federal University of Mato Grosso, sponsored by the Mato Grosso State Research Support Foundation. In this project we have promoted two Seminars on Social Mapping, which occurred in the city of Cuiabá-MT, in 2008 and 2010. In each one about 250 people took part in the seminar, representatives of several social groups of the State. To understand this vigorous broth we used a methodological complexity which composes the epistemological contribution provided by the phenomenology, linked to the praxis of the social map and by the axiological values inspired in the cartography of the imaginary. In this way, we presented in this thesis a general view of the socio-environmental conflicts that were mapped, allowing for a picture of the global landscape of MT. Besides, we offered some settings of the local landscape, showing the struggles of some specific social groups, which are: Mata Cavalo Slave`s Descendant Black Community (Quilombo), Pantanal`s Community of São Pedro de Joselândia Community, Xavante People of the Indigenous Land of Marãwaitsédé and Rubbertappers of Guariba & Roosevelt Extractivist Reserve. Subsidized by the use of technologies of the geo-referenced database processing, we presented a spatialization of the Map on the socioenvironmental conflicts of the State of Mato Grosso with 194 points of conflicts identified, places where death threatens and slave work exists. The participant`s narratives point to the understanding that the mapped conflicts are expressions of the development model that leads to the destructions of the ecosystems and the annihilation of singular forms of life. The mapping reveals that the main direct driving forces of the conflicts are: dispute for the land, dispute for water, deforestation, burning and abusive use of agricultural pesticides. Opposite to the striking practices, several tactics of resistance appear, that go from the legal procedures to the most subversive ones. Thus, from an environmental education point of viewthat aims for the social changes with ecological responsibility, we consider that the results shown in this study may become a referential to the researchers, governments and civil society; that when elaborating public policies, they can take into account the socio-environmental conflicts in their decisionmakings, seeking for the participation as one of the driving forces of the conceptual, political and scientific for the world transformation.
Zoneamento geoambiental da bacia do rio Fartura: abrangendo os municípios de São José do Rio Pardo-SP, São Sebastião da Grama-SP, Vargem Grande do Sul-SP e Águas da Prata-SP, na escala 1:50.000
(Universidade Federal de São Carlos, 2012-03-23) Faleiros, Cássia de ávila Ribeiro Junqueira; Lorandi, Reinaldo; https://lattes.cnpq.br/7794241793056671; https://lattes.cnpq.br/2509932249426122
Grounded on geo-environmental zoning, this study seeks to contribute to the discussion about environmental management in light of sustainable development, thus bringing together economic development and environmental constraints. The 227km2 study area the Fartura river basin comprises the municipalities of Sao Jose Do Rio Pardo, Sebastiao da Grama, Vargem Grande do Sul, and Aguas da Prata, in the State of Sao Paulo, Brazil. The purpose of this study is to propose ways to organize activities as the populations of these municipalities increase, thereby promoting sustainable occupation of the physical environment in accordance with existing urban planning guidelines and legislation. To this end, geo-environmental zoning of this river basin was conducted by means of remote sensing and geo-processing (GIS) technologies. From cartographic documentation and field/lab work results, an environmental diagnosis was produced, including information relevant to environmental planning of the watershed in question. During prognosis, several occupation scenarios for the Fartura river basin were worked out for the 1987, 2000, and 2010 periods. They shed light on the urban expansion dynamics, land use/economic activities, and native vegetation conservation patterns of these municipalities. This prognosis ultimately indicated emerging occupation trends for this river basin and brought about guidelines for land-use planning. Moreover, it was possible to verify that its bedrock is quite homogeneous, 70% of which pertaining to the Varginha Complex. With regard to its soil texture, it was found that 47% of the Fartura river basin soil is sandy and that 86% of the soil composition of the total watershed area is over 50% sand. As to its declivity, it was shown that although 14% of the water basin area displays declivities higher than 30%, most of which falls within the 5%-20% declivity range. This factor, along with its soil texture, suggests a high likelihood of erosion processes happening in this water basin. In addition, inappropriate land use in APPs (Permanent Conservation Areas) can lead to erosion and silting in sections of the watershed area where sandy soil prevails and to flooding where more clayey soils occur. It was also attested that 35% of the area has induced occupation and 24% restricted occupation. The remaining sections should be occupied in a controlled manner under specific conditions and their use should combine farming with cattle-raising, with a view to both land rotation and soil fertility. Level sections of the Fartura river basin area may profit from mechanized farming, to which soil management/conservation techniques must be applied. As to urban occupation, the area under study showed a gradual increase (1.19%).