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Comportamento dos preços de terras em região de fronteira agrícola e em áreas tradicionais
(Universidade Federal de São Carlos, 2012-03-29) Ferro, Aline Barrozo; Castro, Eduardo Rodrigues de; https://lattes.cnpq.br/5702172673123334; https://lattes.cnpq.br/1742640723524757; Figueiredo, Adelson Martins; http://lattes.cnpq.br/2582161065438214
This study aims to evaluate the impact of some factors on prices of agricultural land in three different regions: agricultural frontier (in the south of Maranhão, south of Piauí, eastern region of Tocantins and west of Bahia), transition area (relatively recent agricultural use of the land; however, it already represents a major soybean producing region, such as the Central-Western region in Brazil) and developed (more traditional agricultural areas, such as the South of Brazil). The period of the analysis is from 2002 to 2010, due to the recent availability of prices of regional lands. Several studies regarding the land market were analyzed; consequently, some factors related to the revenue obtained with land, to the technological level, to the infrastructure, to the need of credit, to the availability of land to expand crops and to one factor linked to expectations of agents. The elasticity in relation to the land price was obtained, using the econometric model of panel data. Soybean prices, which represent the revenue of land, had a positive relation with the price of this factor. Moreover, it was possible to verify that, in less occupied regions, an increase in the demand for area may bring negative impacts on its prices, because of the higher elasticity of the land supply and the possibility to convert raw lands and pastures in agricultural areas. This occurs because the land conversion shifts the supply curve to the right, which might impact negatively the land price. On the other hand, in the developed area, the relation is positive, since the land supply is almost inelastic. The factor of speculation was very important in the agricultural frontier region, differently from what was observed in other regions, which has highlighted the sharp interest of investors groups interested in the potential of the land valuation in that region in the period considered.
Reação de deslocamento gás-água em catalisadores de platina suportados em TiO2-CeO2
(Universidade Federal de São Carlos, 2012-03-29) Cesário, Gabriel; Assaf, José Mansur; https://lattes.cnpq.br/9563312407691130; https://lattes.cnpq.br/0960412419762463
In this work platinum catalysts supported on CeO2, TiO2, TiO2-CeO2 were prepared for application in water gas shift reaction also called Shift or well known by the letters WGSR - Water Gas Shift Reaction. The mixed titanium dioxide modified with cerium dioxide supports and platinum supported catalysts were obtained by the wet impregnation method, the two supports of titanium dioxide (Degussa and Alfa Aesar) was stabilized by thermal treatment and cerium dioxide support was obtained by thermal decomposition of its precursor. The supports and catalysts were characterized by fluorescence spectroscopy X ray (FRX), X ray diffraction (XRD), the BET method for specific area, CO chemisorption and temperature programmed reduction (TPR). On initial tests the catalysts were activated in situ and tested for WGSR ranging systems that includes the HTS (High Temperature Shift) at 450 350 ° C and LTS (Low Temperature Shift) at 350 200 ° C, and then tested only under LTS conditions. The composition of effluent stream from the reactor was analyzed online by gas chromatograph. It was noted that low charges of cerium oxide is sufficient to enhance the activity and stability of the catalysts supported on mixed oxides when compared with catalysts supported on bare oxides. The effluent stream from the reactor showed compositions similar to those expected when taken into account the ratio H2O/CO. Thus, it was concluded that Pt/Ti-CeO2 is a promising catalyst for application in WGSR reactor.
Correspondência fazer-dizer : variáveis de controle e condições de manutenção e generalização
(Universidade Federal de São Carlos, 2012-03-29) Cortez, Mariéle de Cássia Diniz; Rose, Julio Cesar Coelho de; https://lattes.cnpq.br/3386857761295187; https://lattes.cnpq.br/7927746584626515
The present proposal is based on the assumption that verbal responding is an operant behavior established and maintained by reinforcement contingencies. Study 1 evaluated the effects of three different correspondence training methods on the maintenance of eleven children s accurate self-report. Doing consisted of reading aloud a written word presented on a computer s screen. Saying consisted of reporting on the accuracy of the textual response after the computer s automated feedback. Following report accuracy evaluation, participants were assigned to different correspondence training methods. Five children were exposed to Training A (continuous reinforcement), three to Training B (continuous and intermittent reinforcement plus instructions), and the remaining were exposed to Training C (continuous and intermittent reinforcement only). After training criteria was met, participants were re-exposed to report accuracy evaluation sessions. Follow-up sessions were then conducted 30 and 60 days later. All training methods were effective in maintaining accurate self-reports for eight participants. Low accuracy during initial sessions (report accuracy evaluation) seemed to predict low maintenance over time. Study 2 investigated the role of the audience (computer, experimenter, and peer) on children s self-report accuracy. Participants were six children who exhibited high do-say correspondence during report accuracy evaluation sessions. The Audience Test evaluated the frequency of accurate reports as a function of different audiences. Only the correct and accurate reports were followed by points. The amount of points required to obtain the high preferred item, however, was higher than the amount received during the session. At the end of each session, participants reported how many points they obtained. Self-report accuracy was evaluated in three conditions: while engaging in the task, while reporting to the audiences, and while choosing the item. Five out of six participants self-report accuracy decreased in at least one of the three conditions as a function of the different audience s presence. After correspondence training was conducted, previous do-say correspondence levels were recovered. Audience seemed to be a relevant controlling variable on children s self-report accuracy since the presence of different audiences controlled different patterns of correspondence. Study 3 investigated the effects of errors on six children s self-report accuracy as a function of the nature of the task (academic and nonacademic), and verified generalization of a do-say correspondence training across tasks. Doing consisted of reading aloud written words, playing a computer game, announcing the result of mathematical operations, and naming different auditory or visual stimuli related to music. During baseline, the frequency of corresponding reports was evaluated as a function of the different tasks presented. Correspondence training was conducted, initially, only to the task in which participants exhibited the lowest levels of accuracy. After training criteria was met, generalized dosay correspondence of untrained tasks was then tested. Academic tasks produced the lowest levels of correspondence during baseline sessions. Four out of six children exhibited generalized say-do correspondence after the first correspondence training employed and the remaining, after a second training was conducted. Results indicated do-say correspondence as a generalized operant behavior.
Tratamento metrológico e quimiométrico de dados de ressonância magnética nuclear para amostras de biodiesel em diesel
(Universidade Federal de São Carlos, 2012-03-29) Gambarra Neto, Francisco Fernandes; Ferreira, Antonio Gilberto; https://lattes.cnpq.br/3676462220401452; https://lattes.cnpq.br/8404572138177315
The development of instrumentation in Nuclear Magnetic Resonance (NMR) increased the sensitivity of the technique, allowing samples in micro and nanogram scale can be examined. These new technologies enabled the NMR technique was seen as an analytical tool for the quantification of substances in addition to their use in identifying as traditionally did. Quantitative Nuclear Magnetic Resonance (qNMR) is a very important area that is not widely used in analytical chemistry, with the need for a validation study to verify its ability to quantify by a metrological point of view. The application and validation of methods minimize the potential problems associated with the analytical method and also lends credence to the method studied, providing comprehensive information about many important aspects that reflect the behavior and reliability of the method. The validation studies of methods RMNq were performed in accordance with ISO / IEC 17025 and ISO GUM. The validation of the method is followed by measuring the uncertainty of measurement qNMR and its importance has been widespread in the analytical chemists area and also in the chemical society in general. The rules for establishing chemical activity as a source of patterning the selectivity studies, investigating the effects of interferents likely in the samples, and for the NMR technique, it is superior to many other analytical instruments. Therefore, the objective of this study was to provide quantitative and alternatives tools, taking into account the metrological quantification of substances by 1H NMR, which is something absolutely new for the Brazilian market. The measure of the selectivity was performed using quantification chemometrics in the spectra of 1H and 13C NMR. Metrology of the main interfering in the 1H NMR technique was studied to quantify the levels of biodiesel in commercial samples and standards of diesel in different proportions in the mixture of biodiesel BX. This study led to the separation of two sets of samples which, by classification using the chemometrics algorithm Successive projection algorithm - Linear Discriminant Analysis (SPA-LDA), are widely separated in diesel fuel containing sulfur in 1800 and 500 ppm . The selectivity was calculated by the quantification chemometric by the algorithm SPA - Multiple linear regression (SPA-MLR) of sulfur content, the density at 20°C, the distillation temperature to 50% and 80% of diesel oil, the cetane number and flash point compared to the results obtained by laboratory (Laboratório de Combustíveis do CCDM/DEMa Universidade Federal de São Carlos) accredited by the ANP (Agência Nacional de Petróleo e Biocobumstíveis).
Integração do processo de cristalização de frutose por adição de antissolvente
(Universidade Federal de São Carlos, 2012-03-29) Crestani, Carlos Eduardo; Giulietti, Marco; https://lattes.cnpq.br/7703659740618915; https://lattes.cnpq.br/4466916726010127
Fructose (C6H12O6) is a monosaccharide with increasing industrial interest, and with some advantages over other sugars, facts that have motivated many studies about its production from its aqueous solution, by crystallization. Fructose crystallization occurs, in general, with the addition of ethanol as anti-solvent, aiming the reduction of its solubility and metastable zone width. Addition of ethanol makes feasible fructose crystallization, however, generates other negative factors to the process, as economically, because of its cost, as environmentally, because of the generation of the mother-liquor as a highly concentrate ethanol residue. These factors motivated the study of separation and reuse of the mother-liquor, recycling both ethanol and the diluted solution of non-crystallized fructose back to the process. Besides, the process was integrated into the calcium gluconate enzymatic production, through the reuse of its byproduct as raw material of the process of this work. Because of the absent of experimental data in literature, some methods of calculation of the vapor-liquid equilibrium (VLE) of the ternary solution were tested and compared, providing the choice of some of them to determine the equilibrium data. The method which obtained the best results was the AUNIFAC, and this method was used to provide the energy calculations of the process, by the evaporation and distillation temperature calculations. The cost of energy together with the replaced ethanol, were used to determine the operational cost, allowing the comparison of different operational conditions of the global process. With temperatures above 100°C in laboratorial experiments, the solution became yellow, a behavior of fructose caramelisation. It can occur because of the thermal degradation of fructose producing hydroxymethylfurfural and it prejudices the crystallization process. Because of it, it is necessary to avoid temperatures above 100°C. Finally, the integrated process made feasible crystalline fructose production by crystallization.
Aísthesis e teoria da percepção no Teeteto
(Universidade Federal de São Carlos, 2012-03-29) Silva, Daniel Reis Lima Mendes da; Souza, Eliane Christina de; https://lattes.cnpq.br/5658382257368048; https://lattes.cnpq.br/7036491650112900
In this thesis, we investigate in the first part of the Theaetetus how Plato develops the concept of aísthesis, demonstrating that at first he alternates it between the senses of mental perception and bodily sensation, and finally fixed it as mere passive reception of data from the five senses. This definition has as its objective, unlink it from the character of opinion, that Protagoras associated to the term, while inserting it into the size of the sensible world, whose key feature is the constant change. From this viewpoint, we investigate the centrality of the sense of aísthesis within the theory of perception shown in the secret doctrine, in this dialogue, which in our view, would be a first attempt of Plato to a descriptive theory of perception that explains how we capture sensitive data by through the soul, accepting shares in an effort dialectical thesis of Protagoras and Heraclitus. We also analyze the link between the theories of Theaetetus, Protagoras and Heraclitus exposed in this first part of the dialogue, and how they interrelate in order to make clear that Plato maintains intact his Theory of Forms.
“A apoteose da imagem”: cineclubismo e crítica cinematográfica no Chaplin-Club
(Universidade Federal de São Carlos, 2012-03-29) Santos, Fabricio Felice Alves dos; Araújo, Luciana Sá Leitão Corrêa de; https://lattes.cnpq.br/9890886509956837; ttp://lattes.cnpq.br/5646532889487401
Founded in Rio de Janeiro in 1928, the Chaplin-Club is considered the milestone of ciné-clubs and of film criticism in Brazil. Since the beginning of its activities, the club used to release O Fan, a vehicle dedicated to spread the group’s ideas. The objective of this dissertation is to analyze the activities of Chaplin-Club and its members’ reflections on cinema. Having as main source the nine issues of O Fan, this work aims to establish a dialogue among the different conceptions of cinema expressed by the club members and evaluate the set of concepts applied by them in the construction of their critical parameters, in order to present the particularities of Chaplin-Club’s thoughts and its specificity in the Brazilian context of the time.