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Avaliação do catalisador CTA-MCM-41, modificado por poliacrilatos, na transesterificação de monoéster
(Universidade Federal de São Carlos, 2014-03-24) Cruz, Fernanda Tátia; Cardoso, Dilson; https://lattes.cnpq.br/2462847535959232; https://lattes.cnpq.br/9642834984473672
The silica hybrid CTA-MCM-41 (where CTA is the cetyltrimethylammonium cation) was synthesized and used in the transesterification of ethyl acetate with methanol. This is a model reaction used to test basic catalysts for the production of biodiesel from vegetable oils and fats. The basic sites in the catalyst consist of siloxy anions associated with CTA cations. In earlier work, it was found that progressive deactivation of the catalyst occurred when it was reused, due to leaching of the CTA cations located within the pores and on the external surface, resulting in partial loss of the basicity required for this type of reaction. The challenge of the present work was to stabilize the catalytic activity of CTA-MCM-41 by restricting the loss of cations from its interior (since the basicity derives from the interaction between the CTA cation and the siloxy anion). To this end, novel modifications were made to the synthesis of CTA-MCM-41, involving the encapsulation of acrylate monomers in the hydrophobic interior of the micelles followed by their subsequent polymerization using the application of ultraviolet irradiation together with a photoinitiator. The polymers formed then interacted with the hydrophobic tails of the micelles, which restricted the exit of CTA from the interior of the pores, hence improving the stability of the catalyst. The combination of the traditional synthesis method with polymerization using a microemulsion is innovative, because there are no reports in the literature that describe a synthesis in which the initial step is performed using emulsified polymers. The emulsions and the synthesized solids were evaluated using small angle X-ray scattering (SAXS). The materials were also analyzed by Xray diffraction, elemental (CHN) analysis, infrared absorption spectroscopy, scanning electron microscopy, and thermogravimetry. All these techniques helped to identify the presence of the monomer, as well as the polymer, in the channels of the CTA-MCM-41. It was confirmed that the presence of the polymer increased the catalytic stability of these new silica hybrids applied in the transesterification reaction.
Modelagem e simulação de uma destilaria autônoma de produção de etanol de primeira geração (E1G)
(Universidade Federal de São Carlos, 2014-03-24) Fonseca, Gabriel de Castro; Giordano, Roberto de Campos; https://lattes.cnpq.br/4378950347916839
Most of the operations in an autonomous distillery for production of ethanol are carried on in a continuous fashion. The fermentation stage, however, may be projected to work either continously or semicontinuously. The steady-sate continuous operation (after the start-up) may be easily coupled to other unit operations of the process. On the other hand, in the semicountinuous operation, each fermentation vat operates in unsteady state, thus it is necessary to design a set of vats that enables the coupling between the fermentation and the process, which may be challenging. This study intended to implement mathematical models in EMSO process simulator of both industrial configurations of the fermentation process: a system of six parallel fed-batch bioreactors and a system of four continuous steady-state bioreactors in series. The process was modeled at macroscopic level based on the material balances for cells, substrate and product. Kinectic models accounting for product and substrate inhibition were used. Both configurations were added to a previously built model of a complete autonomous distillery in which the fermentation stage was represented by a stoichiometric conversion model. In the fed-batch process, due to the solution of mass and energy balances in the fermenters, it was possible to observe the temporal evolution of variables such as the concentrations of yeast, sugar and ethanol in their interiors, the volume of solution in each fermenter and the rate of heat removal needed in order to keep the fermenters temperatures constant. The simulated autonomous distillery processes 500 t/h of cane with varying levels of sucrose. For a content of 13% sucrose, 338.0 t/h of centrifugated wine were obtained in the continuous operation, containing 8.3% by weight of ethanol, which resulted in the production of 30.1 t/h of hydrate ethanol containing 93.5% ethyl alcohol in weight. In fed-batch operation, 417.5 t/h of centrifugated wine (6.3% ethanol by weight), which resulted in 27.9 t/h of hydrous ethanol (93.5% by mass). In both configurations, simulations were performed to evaluate the influence of the sucrose content in the process input (11 to 15% by weight of sucrose) over the process response. The results of these simulations were compared to those obtained for the model of stoichiometric conversion under the same conditions. Regarding the three evaluated configurations for the fermentation stage, it was observed that the model of stoichiometric conversion can be properly employed in the simulations, being mostly suitable for optimization studies of the autonomous distillery with semicontinuous operation due to its fast convergence. However, it is worth mentioning that the inhibitory effects are not reproduced in the fermentation step for this model, thus preliminary studies should be performed using the mathematical model implemented in continuous or discontinuous configuration.
O MSN de papel: um gênero também argumentativo
(Universidade Federal de São Carlos, 2014-03-24) Moreno, Carolline Gabriela Leite; Brito, Maria Isabel de Moura; https://lattes.cnpq.br/2643801218794087
MSN Paper proposal is constituted of written interaction, in the form of conversation, via notebook paper. It can involve two or more students, having that the interaction is developed through the exchange of rotations which may have the format of question/answer, assertive/response. At long last, this is the development of chat talk inside the classroom with a different tool from that usually used, once this is what is available to them. This proposal was adopted as an alternative pedagogical practice to work on the argumentation of an eighth grade (ninth year), working as a kind of unlock activity to the participant students. However, the object to be analyzed was not taken in its original format in the analysis herein developed, but in a deployment of type, once it was used for the pedagogical work with the argumentation, what makes it to transmute in another type. This transmutation of type consisted in the elaboration of a dialogue in the form the students already knew in pairs, from a theme proposed by the teacher. This practice was adopted in view of the complexity that the conventional argumentative types have assumed to most of the students through the documents and guidelines of education, what makes a lot of students be unsuccessful in the production of this gender. Therefore, the purpose is to expose this alternative practice of argumentative text production in the classroom, used as an ―unlock‖ activity of argumentation, aiming to comprehend its operation and effectiveness, presenting the characteristics of the type ―paper MSN‖ and justifying the reason it configures as that; besides, we will analyze it as an activity responsible/responsive and investigate the presence of that kind of argumentation. It is important to point out that the aim of this paper is to evaluate the language operation, of the argumentation, and not to describe a methodological proposal of the work with the gender, although the paper pervades through that question. The text produced by the students will be analyzed taking into consideration two perspectives: the concept of responsiveness/responsibility of Bakhtin and other aspects which are attached, and the theory of argumentation studied by Selma Leitão, who possesses a perspective cognitive- psychological. We will consider that both the approaches are relevant to the treatment of the gender analyzed, one because it treats the language operation, and the other because it works more specifically with the argumentation, treating as well questions related to the education. As from the analysis realized, we can conclude that the gender enables the students to comprehend the operation of the argumentation; even when they assume, in large scale, the speech of others, of adults, that does not mean that they are omitting themselves, on the contrary, they choose a position to defend. There is a responsible activity there, although the communicative relations will occur in reason of the other, our acts are of entire responsibility, because they are unique and unrepeatable. We understand, as well, that the texts will grow, create a body, always complementing the enunciation produced by the interlocutors; in different moments of the texts analyzed, the idea of an interlocutor is retaken and complemented by the other, what reaffirms the dialogism, the responsiveness. Concerning to the argumentation, in accordance with the theory studied by Leitão, this one occurred in the texts, that means, the format of the gender permitted it to be developed.
Encontro de palavras em procedimentos restaurativos uma visão possível sobre a linguagem e seu funcionamento
(Universidade Federal de São Carlos, 2014-03-24) Dias, Ana Beatriz Ferreira; Miotello, Valdemir; https://lattes.cnpq.br/9131819326282708; https://lattes.cnpq.br/4121810228256604
Wiht this research, we offer our counterwords to practices of restorative justice developed in instances of juvenile criminal justice. Restless with the tactics of prevention and solution of conflicts that are being proposed by the restorative justice, we look forward to comprehend language elements and their operation on a modality of meeting called Restorative Circle , usually considered the main part of restorative procedures. More specifically, this work deals with the possibility of finding, in restorative practices carried out on oficial justice system, what Ponzio understands by other word , a singular and free word, marked by the right of otherness. Thus, the objective of this work consists in put ourselves listening to other word on restorative practices inserted in a context dominated by retributive justice, hegemonic view in judiciary system. To do this work, we take as its central signical materiality audio and video records from two Restorative Circles that occurred in 2009, by the Programa Justiça para o Século XXI (Justice for the 21 Century Program), by the Central of Restorative Practices Court of Childhood and Youth, to support the activities of the Third Pole of Regional Court of Childhood and Youth in Porto Alegre, instance that is responsible by the execution of social and educational measures. The comprehensions of the texts are based on the theoreticalmethodological assumptions suggested by Bakhtin Circle, which are here developed according to the evidenciary research paradigm proposed by Ginzburg. Considering the interpretive path we have traced in this research, we divided the methodology in two great parts: steps of selection and steps of comprehension. The first one comprises a set of necessary actions on the beginning of this research, envolving, to this the selection of objective reality, from the choosing of the central materialities to the checking of the research feasibility. The second one refers to the set of methodological guidelines adopted to guide the comprehensions of the texts. This step was done based on the four necessary moments of analysis and interpretation of the texts proposed by Bakhtin and developed by Geraldi: 1) The perception of the material dimensions of sign in this work, the unity of perception was centered on the word as an ideological sign. 2) Its recognition. 3) The comprehension of its meaning in certain contexts. 4) The active-dialogic comprehension of the texts. Witht this work, we understand that the meeting of words in the Restorative Circles have ideological conditions and practices to contribute to both the deconstruction of the realities of the identity humanism, world view that sustains the dominant social relations, and the construction of a new humanism, the otherness one. Listening to the other word is a way tha could take to the humanization (the otherness humanism) of the social relations among victims, ofensors and their comunities of support, contribuiting, consequently, to the judiciary in order to reframe its actions.
Classificação de data streams utilizando árvore de decisão estatística e a teoria dos fractais na análise evolutiva dos dados
(Universidade Federal de São Carlos, 2014-03-24) Cazzolato, Mirela Teixeira; Ribeiro, Marcela Xavier; https://lattes.cnpq.br/0300141044144026; https://lattes.cnpq.br/5404143204431052
A data stream is generated in a fast way, continuously, ordered, and in large quantities. To process data streams there must be considered, among others factors, the limited use of memory, the need of real-time processing, the accuracy of the results and the concept drift (which occurs when there is a change in the concept of the data being analyzed). Decision tree is a popular form of representation of the classifier, that is intuitive and fast to build, generally obtaining high accuracy. The techniques of incremental decision trees present in the literature generally have high computational costs to construct and update the model, especially regarding the calculation to split the decision nodes. The existent methods have a conservative characteristic to deal with limited amounts of data, tending to improve their results as the number of examples increases. Another problem is that many real-world applications generate data with noise, and the existing techniques have a low tolerance to these events. This work aims to develop decision tree methods for data streams, that supply the deficiencies of the current state of the art. In addition, another objective is to develop a technique to detect concept drift using the fractal theory. This functionality should indicate when there is a need to correct the model, allowing the adequate description of most recent events. To achieve the objectives, three decision tree algorithms were developed: StARMiner Tree, Automatic StARMiner Tree, and Information Gain StARMiner Tree. These algorithms use a statistical method as heuristic to split the nodes, which is not dependent on the number of examples and is fast. In the experiments the algorithms achieved high accuracy, also showing a tolerant behavior in the classification of noisy data. Finally, a drift detection method was proposed to detect changes in the data distribution, based on the fractal theory. The method, called Fractal Detection Method, detects significant changes on the data distribution, causing the model to be updated when it does not describe the data (becoming obsolete). The method achieved good results in the classification of data containing concept drift, proving to be suitable for evolutionary analysis of data.