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Vivenciar para apreender: o meio ambiente como contexto para o ensino de polímeros
(Universidade Federal de São Carlos, 2014-07-11)
Silva, Márcia Adriana da
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Marques, Clélia Mara de Paula
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https://lattes.cnpq.br/0451284088402660
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https://lattes.cnpq.br/9820357996606419
Through the student‟s desinterest and the difficulties in the teaching-learning process of this science, where the teaching methodology employed traditionally is based on the traditional teaching model of transmission-reception in the memorization of concepts, rules, formulas and their applications are prioritized, this work approaches the use of a teaching sequence based on contextualized activities with CTSA approach to the teaching of polymers in high school, as a way to encourage, stimulate and facilitate the learning. Thus, this study investigated the development of contextualized activities with CTSA approach contribute to students understand chemical concepts related to the theme of the waste that is produced in their homes and specially if it provides them, a critical and reflexive positioning on the relationships between Science, Society, Technology and Environment, which are essential for its role as citizens. To this end, various teaching alternatives have been used in order to facilitate learning. Students from the second grade of high school at the Escola Estadual Enoch Garcia Leal studied diverse teaching strategies: lessons dialogued based on discussions of articles published in Revista Química Nova na Escola , experimental activities, instructional material on polymers and field visit to Recycling Plant. As a way of assessing learning, student answered questionnaires. The results indicate that contextualized activities with CTSA approach is a very important recourse that has much to contribute to the training of students, allowing them to reflect on the environmental problems arising from production and improper disposal of waste, as well as relate to the topic, chemical concepts involved on polymers used in everyday life.
Capital humano: alocações de talentos do ensino superior no Brasil e seus possíveis impactos no crescimento econômico
(Universidade Federal de São Carlos, 2014-07-11)
Shirozono, Luanna Vargas
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Silva Junior, Geraldo Edmundo
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https://lattes.cnpq.br/5138808982229139
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https://lattes.cnpq.br/4261883539405716
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Rodrigues, Rodrigo Vilela
Starting from the concept of human capital and considering it as a synonymous of knowledge, the present thesis collected based on lecture of Human Capital, searching in data of Higher Education in Brazil and studying a part of this topic and the effects over the dynamic of talents in the country. Searching inferences on alternative models of education from China, South Korea and The United States of America. Using as fundamental the HHJK theoretical model, the research concluded that to the period between 2002 and 2012, the distribution and allocation of talents among the knowledge areas / careers from Brazil didn t show a remarkable convergence if compared with state of São Paulo, which is the reference state by representation and importance in the country. Beyond that, the effects of those discrepancies among the occupation can correspond until 95% wage deviation on representative careers.
Estudos de sólidos farmacêuticos através das técnicas de RMN no estado sólido
(Universidade Federal de São Carlos, 2014-07-11)
Oliveira, Lyege Magalhães
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Venâncio, Tiago
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https://lattes.cnpq.br/4438399441102990
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https://lattes.cnpq.br/6690728944762905
Approximately 80-90 % of the drugs on the market are available in solid form, sold as tablets and capsules containing product in a powdered form. A frequent problem associated to the drugs in the solid state is the low rate of dissolution, especially in aqueous medium or in polar environments. Another important feature, which is closely related to the dissolution rate, and consequently the bioavailability of the drug, is the existence of several crystalline forms that the drug can assume during the crystallization. This phenomenon is known as polymorphism and it is a serious problem for the pharmaceutical industry. Since the problem is not so simple to be characterized, it is recommended to use a number of different techniques such as XRD, Raman, IR, thermal analysis and solid state NMR, once they all have at least one limitation. In this context, this work aimed to study pharmaceutical solids by solid state NMR techniques, using matrices such as mebendazole (in polymorphic forms A and C and in commercial samples), diethylcarbamazine (in its free, citrate and maleate forms) and mycophenolic acid as well as its ester mofetil form. A set of techniques for solid state NMR based on CPMAS experiment and its variants (CP-TOSS, CP-NQS e CP-PI) were used, both observing the nucleus of carbon-13, as well as nitrogen-15. Thus, it was possible to differentiate between A and C polymorphs of mebendazole by using these techniques, and still use them in the analysis of commercial drugs. In this context, it was also possible to verify that the technique of solid state NMR can be successfully used to characterize and quantify polymorphs in absolute commercial samples. The data obtained from these analyzes demonstrated the importance of conducting an effective quality control of drugs available in the market when formulated in solid form, since it was verified that some lots sold exhibited the undesired polymorph of mebendazole. Regarding the study involving the free diethylcarbamazine and its citrate and maleate forms, NMR data were consistent and complementary to those reached by X-ray crystallography. With the use of two-dimensional FSLG-HETCOR 1H-13C experiment, it was observed the existence of intra- and intermolecular interactions through hydrogen bonds. NMR data obtained for mycophenolic acid and its ester mofetil form corroborate the structural study of this molecule, previously described in the literature only with X-ray crystallography data. The present results confirm the importance of solid state NMR in the study of pharmaceutical solids, mainly in the analysis of commercial products in Brazil, where their use should be encouraged, since this technique offers considerable advantages in the analysis of this type of product.
Síntese e aplicação do SrTiO3 na fotodecomposição da água para a geração de hidrogênio
(Universidade Federal de São Carlos, 2014-07-11)
Pinheiro, Antônio Narcisio
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Leite, Edson Roberto
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https://lattes.cnpq.br/1025598529469393
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https://lattes.cnpq.br/8901620600165297
Strontium titanate (SrTiO3) is an n-type semiconductor with high chemical and photochemical stability. This wide band gap oxide has a band gap energy of about 3.2 eV as well as a favorable energy for photocatalysis. In this study, we demonstrate an alternative and superior method to produce Nb-doped and undoped SrTiO3 photoanode thin films based on a colloidal deposition process which possess good activity under standard solar illumination conditions. Methanol was used as hole scavenger and the results showed that the semiconductor liquid junction (SCLJ) charge accumulation is not an important mechanism to control the photocurrent density and overpotential. In addition, experimental results suggest that the dominance of photocurrent density is controlled by the potential at the surface space charge layer for the Nb-doped SrTiO3 and by recombination at the depletion layer for the undoped oxide.
Biomassa e produtividade subterrânea no cerrado: relações com solo, topografia e fogo
(Universidade Federal de São Carlos, 2014-07-11)
Loiola, Priscilla de Paula
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Batalha, Marco Antônio Portugal Luttembarck
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https://lattes.cnpq.br/3893228815181339
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https://lattes.cnpq.br/2691455603546958
Plant biomass and productivity are ecological properties that affect community functioning. The belowground biomass of cerrado is underestimated and, therefore, it is important that we know how it is related to biotic and abiotic variables. In the first chapter, we tested for the relationship between different diversity indices and aboveB and belowground biomass. Species diversity and functional divergence positively affected the aboveground biomass, but not the belowground biomass, both in the cerrado and in the seasonal forest. Resource use complementarity led to a better community functioning, but did not predict all the community biomass production, as it disregarded the belowground component. Inclusion of environmental variables and functional traits, in the second chapter, was important to generate models that predicted the belowground biomass. The models were significant, even tough they showed low explanatory power for the cerrado. Foraging for limiting nutrients, altitude, and functional traits related to disturbance were selected in the models predicting the belowground biomass. In the third chapter, we separated fine and coarse roots in two depths. We used structural equation modeling to test for the effects of environmental variables on the belowground biomass in each root category and each depth. We identified soil fertility causing less fine root biomass and recent fire causing less coarse root in the deep soil layer. Shallow root biomass was not caused by any of the ecological processes we studied. Also, aluminum content led to low soil fertility and recent fire caused higher soil fertility, as we expected. The carbon stock of the cerrado and the seasonal forest is large and should not be neglected when estimating the impacts caused by climate and landBuse changes.
O treinamento resistido promove modulações gênica e proteica de sinalizadores do metabilismo glicolítico no fígado de ratas ovariectomizadas
(Universidade Federal de São Carlos, 2014-07-12)
Tomaz, Luciane Magri
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Perez, Sergio Eduardo de Andrade
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https://lattes.cnpq.br/9408953831211309
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https://lattes.cnpq.br/8430651176725216
Menopause is associated with higher risks of metabolic changes that may compromise women s life quality. Glicemia is regulated by the liver which is responsible for glucose storage at postprandial and for glucose efflux in a fastened state. The absence or the reduction of stradiol levels cause glucose intolerance and deregulated insulin output in bloodstream, setting of the insulin resistance process (RI). Hepatic glucose regulation is directly related to the accurate control of gene expression which encodes different isoforms of oxidation proteins and glucose input proteins. Studies suggest that Resistance Training (TR) prevents RI on ovariectomized (Ovx) rats liver. However there are few molecular events that support TR. Objective: To investigate the Ovx and TR effects over protein and gene expression of biomarkers associated with insulin signalization and glucose oxidation in rats liver. Methods: Adults Sprague-Dawley were divided into 4 groups (n=6 each group): Sedentary Sham-surgical (Sham-Sed); Sedentary-Ovx (Ovx-Sed); (Sham-Tr) and (Ovx-Tr). Tr protocol included 1.1 m vertical climbing with tied weight to the rats tail. Each session consisted of 4 to 9 climbing and 2 minutes of resting between the exercises. Training was performed 3 times a week during 10 weeks. Gene expression was analysed using real time quantitative PCR and protein assays by Western Blotting technic. Results: GLUT2 gene and protein expression and PGC-1α gene expression increased significantly; and p-Akt Ser473 protein expression decreased in Ovx group. TR promoted a greater increase of PGC-1α gene expression and further repair of GLUT2 gene and protein expression and p-Akt Ser473 protein expression. Conclusions: The results show the ovariectomy promotes overexpression of molecular markers that induced RI. These findings suggest that TR may play an important role on the RI prevention in Ovx animals through gene and protein expression repairment of the glycolytic metabolism signalling molecules.
Manejo e conservação da agrobiodiversidade no assentamento rural Olga Benário no estado de Sergipe
(Universidade Federal de São Carlos, 2014-07-14)
Almeida, Ana Cristina Oliveira de
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Schlindwein, Marcelo Nivert
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https://lattes.cnpq.br/9690898537150950
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https://lattes.cnpq.br/5341111069893881
The paradigm of the rural development through globalization of agricultural markets has affected the diversity of natural resources and, on the condition of the rural settlements, this situation of loss becomes worse seen the heterogeneity of subjects and the existing structural difficulties. This work aims to analyze through native seeds the local conservation of agricultural biodiversity and the management carried out by the settled farmers in Olga Benário Settlement Project located in Sergipe. Two systems of different treatments were identified and, through indicators of low, medium and high levels of agroecosystem analysis was conducted. In large lots, crops which showed more diversity were the fava bean, maize, bean, cowpeas, cassava, bananas, yam and sweet potato. Highlighting the cultures of cassava which showed that seed exchange network established. The absence of an irrigation system and sufficient supply of fertilizer for the production have been identified as limiting factors for further integration of production. Farmers were presented as potential guardians of seeds, as noted in the analysis of the exchange of cassava manivas network which was more significant in relation to other cultures. The construction of Agroecology is seen as the way for the local knowledge reframing agriculture are transmitted, starting with the rescue of native seeds.
Obtenção e caracterização de nanocompósitos de poliuretano termoplástico reforçado com nanocristais de celulose
(Universidade Federal de São Carlos, 2014-07-15)
Prataviera, Rogério
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Lucas, Alessandra de Almeida
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https://lattes.cnpq.br/9754332336954137
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https://lattes.cnpq.br/5895158357997353
In this study the potential of cellulose nanocrystals (CNC) as a reinforcement of a thermoplastic polyurethane partially obtained from renewable sources (Bio-TPU) was investigated. The nanocomposites were obtained in the melt state and from solution casting. The CNC were obtained from acid hydrolysis of eucalyptus kraft pulp. They were freeze dried and used with and without surface treatment. Two types of surface treatment were employed: polymer grafting and oligomers grafting. Only the effectiveness of the second treatment could be confirmed by FTIR. CNC’ structural and geometric characteristics, crystallinity degree and thermal stability were determined by infrared spectroscopy (FTIR), transmission electron microscopy (TEM), wide angle X-ray diffraction (WAXD) and thermogravimetric analysis (TGA), respectively. The concentrations of CNC were varied between 0.1 and 5.0 wt %. The rheological properties of the nanocomposites were evaluated in the steady state and oscillatory measurements in order to evaluate the level of dispersion CNCs in TPU. The nanocomposites obtained by solution casting showed good dispersion. In the melt state, only those obtained with treated CNC showed good dispersion. The deformation and elastic recovery of the nanocomposites tests in the melt state were evaluated through creep and constrained recoil rheological essays. Their morphologies were studied by small angle X-ray scattering (SAXS) and scanning electron microscopy (SEM). It was possible to prove the inclusion of CNC in TPU did not change its conformation. The nanocomposites were also characterized according to their: i) mechanical properties, through tensile tests, ii) thermal properties, by using differential scanning calorimetry (DSC) and TGA, iii) thermo-mechanical properties, evaluated by dynamic mechanical thermal analysis (DMTA) and iv) optical properties, through opacity the nanocomposites with 5.0 wt % of CNC shown better performance and similar results were found from solution casting and melt state processing techniques.
Preparação de vidros e vitrocerâmicas no sistema SbPO4-PbO-ZnO dopados com manganês e ferro
(Universidade Federal de São Carlos, 2014-07-15)
Siqueira, Renata Fernandes
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Nalin, Marcelo
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https://lattes.cnpq.br/3349586880746735
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https://lattes.cnpq.br/6645436997641022
In the present research project a new glass composition containing SbPO4 ZnO PbO was obtained by melt quenching technique. After a brief study of the matrix, a composition was chosen and doped with MnO e Fe2O3 in quantities varying from 0 to 20 mol%. The next step was to perform a heat treatment above glass transition temperature in order to produce glass-ceramics from the obtained glasses. Then, the vitreous materials were characterized by thermal analysis (DSC), and the structural study of the materials was done using absorbance spectroscopy in the UV-vis-NIR and Raman, besides the electronic paramagnetic resonance (EPR) and fluorescence measurements. Refractive index was measured by M-Lines spectroscopy. The new materials were also characterized by X ray diffraction (XRD), optical microscopic and scanning (SEM) and transmission electronic microscopic (TEM). Finally, magnetic measurements were performed in a magnetic force microscope (MFM). The prepared glass samples have a high refractive index and thermal stability over 100 °C, which may be interesting for optical fiber synthesis. After addition of the paramagnetic metals (Mn, Fe), the thermal stability increased even more. The optical analysis of the manganese doped glasses showed that the ions are in the Mn2+ oxidation state, but after heat treatment the color of the glass changes since a small amount of the dopant cation is oxidized to Mn+3 and some magnetism characteristic may be observed. Even though the optical properties were not good with addition of manganese and iron, the sample showed a significant magnetic response. These results of magnetic analysis are promising for the advance of spin-photonics and may be suitable to design devices for information storage.
O fazer do intérprete educacional: práticas, estratégias e criações
(Universidade Federal de São Carlos, 2014-07-16)
Santos, Lara Ferreira dos
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Lacerda, Cristina Broglia Feitosa de
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LACERDA, C. B. F. de
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https://lattes.cnpq.br/7312070448044165
This research aimed to analyze and discuss the work of the Educational Interpreter (IE), which is a recent professional in our country, and the currently researches on their performance in the classroom are incipient in order to better understanding of the practices, strategies and creations in the process of translation and language interpretation to/from Brazilian Sign Language. This thesis aimed to uncover what is behind the work of interpretation from one language to another, what factors influence either positively or negative, the performance of the IE, considering the authorship, the another s discourse, the polysemy of the language involved, and, specially, the creation or transcreation. This research is based on Bakhtinian theoretical frameworks (2009, 2010), because we believe that the language is a concrete activity and is related to life and its character is dialogic. It is not possible the understanding of the IE performance unless with unique acts, which are possible in a specific time and space with real interlocutors that enunciate and expect answers. In order to embrace the entire events surrounding the IE s work (even aware of the impossibility of it), this research were conducted as a qualitative investigation influenced by microethnographic approach. The data collection was done over the second semester of 2011 and it s been observed four IE during their work in four different classrooms, whose classes were taught by three teachers from the final years of elementary school in an Inclusive Educational Program school and bilingual teaching for deaf. In order to tape-record the natural and quotidian situations of the translation process conducted by the IEs we followed the classes and everything that happened during the classes. From the data collected it has selected nine episodes to be analyzed, which were divided into three main axes, titled: the collective construction of knowledge in a context of dialogue-education ; narrative supported by imagetic representations . The analysis and reflections on the IE s performance led us to the construction of a thesis that the work of Educational Interpreter is not restricted to the utterances translation and interpretations. Its daily practices go beyond this aspect. The Educational Interpreter is co-author of the discourses delivered by teachers in classroom. We assume that the classroom context is so complex that the teachers utterances would be untranslated (as some on the translation field authors have said), not because of linguistics issues or by their way of presentation, but because of lots of elements involved. Finally, we list some notes that were relevants to the Educational Interpreters training in order to contribute to these professionals from new perspectives.
Síntese, caracterização e estudo de nanômeros de silício como reforço mecânico em resinas acrílicas a base de PMMA
(Universidade Federal de São Carlos, 2014-07-17)
Lourenço, Rodrigo Vinicius
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Leite, Edson Roberto
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https://lattes.cnpq.br/1025598529469393
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https://lattes.cnpq.br/2428327594608532
The search for improvements in material properties has been studied extensively and fabrication of polymeric nanocomposites stands out for having excellent mechanical properties. In this work, silicon nanomers were prepared by solgel process and grafted in a poly(methyl methacrylate) (PMMA) matrix by powderliquid polymerization, a very common process in prosthodontic procedures to polymerize acrylic resins. Two different types of nanomers were prepared: nanoparticles of silicon dioxide (NPs SiO2) from the tetraethylorthosilicate (TEOS) as precursor and molecules of polyhedral oligomeric silsesquioxane (POSS) from the methyl trimethoxysilane (MTMS), both using the silane coupling agent 3-(trimetoxisilil) propyl methacrylate (TMSPM) also as precursor. The nanomers were produced at different concentrations and embedded in the polymeric matrix after 1 and 7 days to form the PMMA/SiO2 and PMMA/POSS nancomposites. They showed different mechanical behavior with respect to present concentration in the matrix, for PMMA/SiO2 nanocomposites best results were obtained for flexural strength, flexural modulus, yield strength and surface microhardness at low concentrations (less than 1%), while PMMA/POSS with about 1,5% presented better results for flexural strength, flexural modulus and microhardness. In addition, there was a decline to almost all the observed results for the nanocomposites prepared after 7 days compared to those prepared after 1 day, regardless of nanomer and concentration.
Tratamento físico-químico e cultivo de Desmodesmus subspicatus em vinhaça de cana-de-açúcar
(Universidade Federal de São Carlos, 2014-07-18)
Mattos, Luiz Felipe Arjonilla de
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Bastos, Reinaldo Gaspar
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https://lattes.cnpq.br/9329363278429665
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https://lattes.cnpq.br/8003605971716221
The traditional processes of biological dispollution of agro industrial waste water use aerobic and/or anaerobic systems, which generate biomass without commercial value and inevitable effluent nutrient losses. Alternatively, it s being studied the microalgae and cianobacteria application for a potential protein, lipid and other biomass constituent production for a minimization of the pollutant impact and as a way of valuating the residue. This way, heterotrophic cultivation of microalgae, is a proposal that could increase the viability of waste water treatment, once it uses organic compounds for the growth of this microorganisms in absence of light, being researched together with the bioremediation of effluents. Vinasse is a waste water highly produced in the fermentation-distillation process for the sugarcane based ethanol production. Depending on its biochemical composition in terms of organic matter and nutrients, the use of vinasse appears to be attractive as a substrate for biotechnological process development. Besides, physical-chemical treatments like pH adjusting and suspended solids flocculation must be studied for its use viabilization. D. subspicatus is a Chlorophyceae which has presented high cellular viability in cultivations using domestic and industrial waste water as substrate, easily tolerating temperature and pH variations. This said, this study aimed the the physicalchemical treatment of coagulation-flocculation and the heterotrophic cultivation of D. subspicatus in sugarcane vinasse aiming the biomass production. The results pointed that pH and aeration had low influence in the cultivation, and the ideal batch time is near 9 hours, lowering the effects of bacterial contamination. The physicalchemical treatment was able to remove COD at the maximum of 40% using calcium hydroxide and 60% using aluminum sulfate. The optimization of the process conditions raised the lipidic productivity from 69 to 244,8 mg.L-1.day-1, suggesting the viability of the heterotrophic cultivation of D. subspicatus in vinasse.
O trabalho do agente comunitário de saúde na estratégia saúde da família: encontros e desencontros de uma prática em São Carlos/SP
(Universidade Federal de São Carlos, 2014-07-18)
Vieira, Kátia Cristina dos Santos
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Ogata, Márcia Niituma
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https://lattes.cnpq.br/3274294833403570
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https://lattes.cnpq.br/2220493766193400
This is a descriptive study with qualitative approach, more specifically a case study. It aims to analyze the work of Community Health Agent (ACS), from the perspective of health user and ACS itself, identifying the activities undertaken by these actors, perceptions of ACSs about his role on the team for the individual and collective care assitence, and the perceptions and expectations of users regarding the work of the ACS. The subjects were six ACSs from a unit of Family Health Program of city São Carlos, and four users of the health service and spokesman in the Local Health Council. Theoretical frameworks that supported this study and who were the object of theoretical study: family health, work and health care directives of the Brazilian Unified Health System (SUS).The research technique chosen for data collection was individual semi-structured interviews and data analysis used the technique of thematic analysis. The data collected with ACS and users were analyzed separately and yielded on the following categories: what is to be ACS: between the ideal and the real; organization of daily work of the ACS; demotivation and impotence in the face of adversity; lack of Permanent Education in Health: choking the work of ACS; who is the ACS to me; the real and the ideal work of ACS, and a user's perspective; the effort to strengthen the work of ACS. The results of this study allowed an approximation of the difficulties and easiness from everyday work of the ACS, sometimes demotivating elements, sometimes augmenting the practice of this worker. It was possible to identify the multifunctionality of ACS as one reason for the loss of identity from that worker before the population. As for users, the expectation that the ACS contributes to citizenship, advising people of their rights and duties, ie, not limited in their speeches to the technical work of the ACS was found, but contemplated the political and social dimension in the role of this worker. Research indicates that the change in the health production model depends not only on a worker-ACS- neither simple deployment of new family health teams. A joint effort of all health workers and a critical-reflective analysis of their own practices, reverberating effective change in health production and consolidation of SUS.
Determinação de Cd, Co, Cr, Cu, Ni e Pb em cosméticos infantis empregando técnicas espectroanalíticas
(Universidade Federal de São Carlos, 2014-07-18)
Augusto, Amanda dos Santos
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Pereira Filho, Edenir Rodrigues
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https://lattes.cnpq.br/3394181280355442
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https://lattes.cnpq.br/0641218916974686
In this study were developed two methods for sample preparation: one for children s eye shadow and another for chidren s lipstick. In the optimizing process, variables such as nitric acid concentration (2 or 7 mol L-1), sample mass (100 or 250 mg), heating time (1 or 3 hours) and concentration of Triton X-100 (5 or 25%) were investigated. The instrumental parameters of ICP OES were optimized in order to find a good working condition for the analytes determination. In the beginning it was performed a fractional factorial design 29- 5 (nine variables) and, after variables selection, a fine adjustment using Central Composite and Doehlert designs was made to study the most important variables (radio frequency power and nebulizer gas flow rate). In order to evaluate the regression models proposed, responses like LOQ and recovery for each analyte and in each view mode (radial and axial) were taken into consideration using desirability function. From the generated models it was possible to find the compromise condition with radio frequency power of 1200 W and a nebulizer gas flow rate of 0.825 L min-1. The methods developed for the preparation of the samples were applied to 22 samples of children cosmetics (14 eye shadows and 8 lipsticks). The analytes were determined using ICP OES (Cd, Co, Cr, Cu and Ni) and GF AAS (Pb). The majority of the concentrations obtained were lower than the international normatives, but the Pb values ranged from
O domínio prévio à definição das palavras: crítica à proposição como lugar do sentido a partir das Investigações Filosóficas de Wittgenstein
(Universidade Federal de São Carlos, 2014-07-18)
Zunino, Tatiane Boechat Abraham
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Ferraz Neto, Bento Prado de Almeida
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https://lattes.cnpq.br/0084436724293824
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https://lattes.cnpq.br/9466880793137887
This thesis seeks to examine the hypothesis that the meaning has not in its foundation the proposition and the words. That language does not inaugurate the truth in an enunciative joint, but in a practical and comprehensive operation. Thus, through Wittgenstein's Philosophical Investigations, we seeks to explain to what extent can we speak of an ambit of birthing of sense through the analysis of learning by the ostensive teaching of words, i.e., by means of some necessary conditions for the concept acquisition. To do so, we will expose some fundamental aspects of expression learning, both through teaching and verbal learning, namely, the notion of training (Abrichten) and all possible rationality which surrounds it, as well as the ostensive definition of words, trying to defend the position that training is the condition of possibility for the ostensive definition. Thus, it would be the first way of understanding, the birth of sense. After walking this path, it is possible to speak of two levels of access to sense. We try, therefore, to present a sense opening dimension through the linguistic practice in which an expression operates, so that the importance of the ostensive teaching of words is affirmed as the opening of a previous operative field that can enable the denomination. Such field implies that the expressions emerge with its meaning in the everyday praxis previously given, to then become an empirical language and bind to the facts of the world, so that the understanding of an expression assumes, in an essential way, the previous field of language and sense.
Secagem de sólidos porosos granulares
(Universidade Federal de São Carlos, 2014-07-18)
Perazzini, Hugo
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Freire, José Teixeira
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https://lattes.cnpq.br/2270677706718167
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https://lattes.cnpq.br/2676311547535414
In the present work, an experimental study about heat and mass transfer phenomena was carried out during drying of porous media when subjected to an upward flow of heated air. The cylindrical porous media consisted of non-consolidated particles of activated alumina of several diameters. The particulate system was initially characterized based on the achievement of its main physical, thermal and structural properties. The drying experiments consisted of obtaining sorption isotherms at different operational conditions and in determining moisture and temperature data versus time. The temperature profiles were obtained by thermocouples inserted in the porous body and the moisture content data by the gravimetrical method. The concept of time in series analysis was applied to determine the stationarity of the experimental data. The drying of the porous media was studied theoretically based on the context of the pseudo-homogeneous formulation, which led to the estimation of transport parameters of interest considering two situations: the presence of the external resistance to mass transfer and the interfacial equilibrium condition. The estimated transport coefficients were analyzed as constant or variable throughout the drying process. The diffusive mechanisms of mass transfer were estimated in order to identify the limiting one in drying. According to the results obtained, the vapor flux is controlled by liquid superficial diffusion into the particle. However, it was found that the effective moisture diffusivity is a harmonic mean of all the diffusive mechanisms, being the all type of moisture diffusivity of both particles and the porous medium important parameters in drying. The results showed that the drying of the porous medium studied is controlled by external resistance of heat and mass transfer. The pseudo-homogeneous formulation presented restrictions for the situation in which the interfacial equilibrium is admitted in the drying problem.
Conversão de bioetanol em acetato de etila: efeitos das propriedades eletrônicas do metal e estruturais dos suportes nos catalisadores Cu-Ag/ZrO2 e Cu/ZrO2/Al2O3
(Universidade Federal de São Carlos, 2014-07-18)
Freitas, Isabel Cristina de
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Marques, Clélia Mara de Paula
;
https://lattes.cnpq.br/0451284088402660
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https://lattes.cnpq.br/9861067651401873
In both industry and academia the interest in biomass conversions into manufactured products has grown rapidly in recent years. Various products can be obtained from alcohol chemistry such as acetaldehyde, ethyl acetate, hydrogen, and others. Although copper-based catalysts are commonly used in the dehydrogenation of ethanol to acetaldehyde, recently Cu/ZrO2 catalysts have also revealed themselves to be highly active in the onepot transformation of ethanol into ethyl acetate. In this work, we studied the one-pot synthesis of ethyl acetate from ethanol by using two separate series of catalysts, Cu-Ag/ZrO2 and Cu/ZrO2/Al2O3. The characterization of the supports and catalysts were performed by N2 physisorption, X-ray diffraction, thermogravimetry, temperature programmed reduction, Fourier transformed infrared spectroscopy of the adsorbed CO (DRIFTS-CO), X-ray photoelectrons spectroscopy (XPS) and extended X-ray absorption fine structure (EXAFS). In the first part of this work, the study of the series of Cu-Ag/ZrO2 catalysts suggested that the Ag-Cu surface alloying alter the electronic properties in the catalysts surface, as verified by DRIFTS-CO. XPS measurements showed that increasing the Ag content in Cu-Ag/ZrO2 catalysts lead to a higher ratio Cu+/Cu0 on the surface. The predominance of Cu+ species on the surface led to catalysts with higher selectivity to acetaldehyde over ethyl acetate. The second part of this work studied the influences of Cu active phase dispersion on the ZrO2/Al2O3 support. Different Cu+/Cu0 species ratio, as verified by XPS, were obtained by varying the Cu content on ZrO2/Al2O3. Furthermore, the EXAFS results revealed that for the reduced catalyst increasing the Cu loading led to an enlargement in the size of the Cu0 particle. DRIFTS-CO showed that CO adsorption into these catalysts may be occurring on the surface of the copper xvi particles deposited on Al2O3 and/or ZrO2, since ZrO2 may not to be covering the whole Al2O3. Catalytic tests show that the products distribution in the one-pot ethanol conversion is affected by Cu0/Cu+ species ratio on the surface of the catalyst as well as the acid/base properties of the support. The increase of the Cu loading up to 30 wt. % favored the selectivity to ethyl acetate (67 % at 250 oC), due to an optimized Cu0/Cu+ species ratio on the surface of ZrO2/Al2O3 support. Theoretically, by increasing the relative Cu0 concentration, the formation of acyl species increases, which condenses with ethoxy species formed on Zrδ+ and Cu+ Lewis acid sites for the formation of ethyl acetate. Additionally, the Cu content of 30 wt. % provides greater surface coverage of the support ZrO2/Al2O3 suppressing the formation of acetaldehyde condensation products on the ZrO2 surface, such as crotonaldehyde; and further methyl ethyl ketone and diethyl ether formed in the alumina acid sites.
Canais de comercialização de orgânicos: desafios e alternativas de agricultores familiares do leste paulista
(Universidade Federal de São Carlos, 2014-07-21)
Oliveira, Priscila Silveira de
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Marjotta-Maistro, Marta Cristina
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https://lattes.cnpq.br/3987280258617095
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https://lattes.cnpq.br/6102996140263032
This paper aims to describe some market alternatives adopted by smallholders farmers on the distribution channels for organic in natura products. Therefore, besides the literature review on this matter, the methodology includes the collection of primary data based on semi-structured interviews with fourteen smallholders farmers. The interviewees are smallholders farmers from eastern side of Sao Paulo, geographically located between two river basins: Capivari-Piracicaba basin and Mogi Guacu. Farmers are found by snow ball method. It is showed that the distribution channels, so called short channels , are the mainly strategies used on family farming. The market fairs are the sell places which the farmers chose as the best one for their needs. The main reasons for that are the better prices they can get due to the absence of any middleman in the selling process and the closest approach to the consumers. The worst channel in their opinions is the supermarkets due to unfavorable contracts required. Those contracts include lower prices, assuming the products that were over (not sold) and bonus profits to the supermarkets on special occasion to name some of them. This study showed that is important to implement actions to enable organic agriculture and commercialization management, logistics and accounting in the distribution process of these products. Considering this, formal or informal associations for production or commercialization have showed to be more efficient and safe compared to individual work, especially as a strategy for production diversification, constancy in offer and searching for new markets.
Químio-, régio- e estereosseletividades das reações de Diels-Alder de para-benzoquinonas: um estudo teórico
(Universidade Federal de São Carlos, 2014-07-23)
Servilha, Bruno Moraes
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Brocksom, Timothy John
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https://lattes.cnpq.br/7055452150201902
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https://lattes.cnpq.br/1729692550121820
In this work, some computational theoretical studies on the reactivity of para-benzoquinones and their derivatives in Diels-Alder reactions were proposed These studies were done in order to compliment the corresponding experimental studies ongoing in our laboratory. The Diels-Alder reactions between carbomethoxy-parabenzoquinones 16, 17 e 19 and cyclopentadiene furnished type-A cycloadducts whereas in the corresponding reaction of 18, the B-type cycloadduct was formed. The regiosselectivity of these reactions were rationalized by the comparison of the corresponding transition state energies and the relative stability of the cycloadducts. The presence of a methyl group adjacent to group carbomethoxy in the dienophiles 18 and 19 inhibits the conjugation of these group with the ring systen, and the regiosselectivity on these reactions, at first sight, is not predictable. (CONTINUE)...
Anelasticidade em titânio, tântalo e na liga Ti-40Ta
(Universidade Federal de São Carlos, 2014-07-24)
Patricio, Marco Antonio Tito
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Florêncio, Odila
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https://lattes.cnpq.br/2881221058860977
The growing demand for increasingly resistant and biocompatible with the human body implantable materials, has led to an increase in demand for new metallic biomaterials. Some materials, such as titanium and its alloys, especially the Ti-6Al-4V, are widely used in the manufacture of orthopedic implants due to their excellent biocompatibility, high corrosion resistance and low density. However, the characteristics of these materials are not considered optimal, mainly because they have a high value of the elastic modulus when compared to the human bone. Include, that in the last decade studies have revealed diseases associated with elements such as Al and V, present in the alloy Ti-6Al-4V. Thus, it have looked for alternatives to the alloys used as biomaterials, still having one common element titanium, but having no toxic elements such as 𝛽 type titanium alloys, formed by non-toxic elements such as Nb, Ta, Zr, Mo and Sn has shown that lower values of modulus, greater fatigue resistance and corrosion resistance, exhibiting excellent biocompatibility. Accordingly, the alloys formed by Ti-Ta become promising candidates as biomaterials, since it has been observed that the content of Ta affects the value of the elastic modulus. For some compositions of this alloy, lower modulus values of this alloys that are currently used in biomedical applications were observed. However, the alloys formed by Ti-Ta still have properties that have been little studied. Thereby, the objectives of this master s project consist in getting the alloy Ti-40Ta and its characterization by means of the technique of mechanical spectroscopy, as of its elements that compose the alloy. The technique of mechanical spectroscopy to be non-destructive, it is widely used for providing the anelastic spectrum (oscillation frequency and internal friction as a function of temperature) is considered sensitive to phase transitions and dynamic processes, which are essential for understanding the structural changes occurring in these materials. This study was determined the dynamic elastic modulus for the pure Ti and Ta elements, and the Ti-40Ta through flexural vibrations. The elastic modulus found for the alloy at room temperature was (71 ± 5) GPa, which is in accordance with results available in the literature. The value of modulus of the alloy is lower when compared to the commercial biomedical alloys and is closer to that of human bone, which makes the alloy Ti-40Ta a potential candidate to be used in biomedical applications.