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Estudo integrado das etapas de pré-tratamento e hidrólise enzimática da palha de cana-de-açúcar
(Universidade Federal de São Carlos, 2017-10-20) Rocha, Martha Suzana Rodrigues dos Santos; Almeida, Renata Maria Rosas Garcia; https://lattes.cnpq.br/3745446778086537; Cruz, Antonio José Gonçalves da; https://lattes.cnpq.br/1812806190521028; https://lattes.cnpq.br/8946724877286549
The use of lignocellulosic biomass for ethanol production, such as, the sugarcane straw, suggests that additional steps should be included aiming the sugars release, that will be converted to ethanol via fermentative route. In this way, it is essential to conduct a pretreatment step, to disrupt partially the recalcitrant structure, increasing cellulose accessibility to hydrolysis by cellulases. This work aims the study of pretreatment and enzymatic hydrolysis strategies of sugarcane straw. The goal is evaluate the best configuration to bioethanol production, taking into account key factors correlated to these two steps. Firstly, the hydrothermal pretreatment (HPT) was conducted in a straw/water ratio of 1:5 to 1:20 (w/v), at 195°C, 10 min and 200 rpm. HPT was followed by alkaline pretreatment (APT, H2O2 1% v/v, pH 11.5). An experimental design (variables: ratio of wdry straw /vwater during the HPT and temperature during the APT) was performed to choice and optimization of the operational conditions. On enzymatic hydrolysis step, 20 FPU/gcellulose and 15% (w/v) of solid loading were applied. The experimental design responses were: cellulose content and cellulose-to-glucose conversion. It was observed that the enzymatic hydrolysis was not improved after the alkaline pretreatment. Thus, taking into account the high efficience of the hydrothermal pretreatment identified in this study, operational costs concerning the alkaline step can be eliminated. In a study concerning HPT mathematical modeling, the assays were conducted applying 10% (w/v) of solid loading and by vary the temperature (180 a 210°C) and time of reaction (0 to 40 min), aiming the identification, from a proposed kinetic model, the optimal temperature and time regarding to sugars degradation and inhibitors formation. At 195 °C/15 min, the pretreatment reached 85% of hemicellulose removal. This condition promoted a little degradation of cellulosic fraction, only 21%. The models proposed in this work can be utilized for engineering studies, including technical and economic feasibility analysis of 2G ethanol production. In addition to the studies developed in this thesis, enzymatic hydrolysis assays were performed in stirred tank reactors, with a reaction volume of 50-mL, applying solids loading of 10, 20, and 30% (w/v), in batch and fed-batch modes. Experiments were conducted in 3-L working volume, under different feeding strategies of substrate/enzyme (fed-batch), reaching 30% (w/v) of solids loading. The assays showed that as the solids loading increases, a decrease in the cellulose-to-glucose conversion is observed. The experiments conducted in fed-batch mode showed high performance when compared with those performed in batch mode. An increase of 3.4 (10% w/v); 9.2 (20% w/v) and 19.8 % (30% w/v) in the cellulose-to-glucose conversion was obtained, taking into account the assays performed in fed-batch mode. Concerning the assays conducted in 3-L working volume, the results showed that the best condition was the one where the feeding profile was smoother (lower solid concentration added in each feed time, but more substrate additions). Both the power consumption per unit volume and the rheology presented lower values to the condition where the feeding profile was smoother. This behavior indicates that this operational mode is more suitable from process point of view, reaching results industrially feasible in terms of glucose content and the energy consumption.
Análise da suscetibilidade a incêndios por meio de geoprocessamento : um estudo no município de Ribeirão Preto, SP
(Universidade Federal de São Carlos, 2017-10-20) Neves, Luiza de Lima; Bourscheidt, Vandoir; https://lattes.cnpq.br/8224261649535795; https://lattes.cnpq.br/2226821354604207
Fires are among the main environmental problems in Brazil. The country is considered one of the great potentials for the increase of greenhouse gases in the planet coming from the emissions of the burning of vegetal biomass. According to IBAMA, besides contributing to global warming and climate change, fires also pollute the air, cause economic and social damage and accelerate the desertification processes, as well as the deforestation and loss of biodiversity. In the city of Ribeirão Preto (SP), this is a problem that has been aggravating in recent years, mainly due to the recent and long periods of drought, religious ritual practices in the nearby forest and the extensive cultivation of sugarcane in the region. In order to analyze a fire occurrence and susceptibility, different methodologies can be adopted. One of them refers to the use of geoprocessing, which encompasses a series of tools that are of great importance for the collection and analysis of physical information related to geographic space, mainly through geographic information systems (GIS) and remote sensing. They make possible to study large areas quickly and objectively, and allow the interaction between different types of data. Through these tools, this paper aims to analyze the fire outbreaks susceptibility in the mentioned municipality through the identification, survey and weighting of previously established geographical indicators. The proposal of a new model sought to advance the existing methodologies through the inclusion of temporal variation in the study, as well as the use of vegetation indices with medium spatial resolution. The results indicate that the model is efficient for a fire susceptibility analysis, but is substantially dependent on data availability and continuous updating. The final maps emphasize the importance of each indicator and stress the need to explore the temporal variation in the study.
Aforização oitocentista: espaço de discursividades na Revista Illustrada
(Universidade Federal de São Carlos, 2017-10-20) Lima, Rilmara Rôsy; Baronas, Roberto Leiser; https://lattes.cnpq.br/4613001301744682; https://lattes.cnpq.br/5617634759514977
S'appuyant sur le travail théorique-méthodologique de Dominique Maingueneau (2008, 2010a; 2010b, 2011, 2012a e 2014), la thèse actuelle vise à jeter un regard discursive sur le langage journalistique du XIXe siècle au Brésil, plus précisément entre la transition de la période politique monarchique au républicain. Pour tenir compte d'une telle entreprise, plus précisément, nous mobiliserons les concepts formulés par Dominique Maingueneau, à propos de aphorisation, surassertion, scène d'énonciation, citation et détachabilité. Pour composer le fichier de recherche, nous avons sélectionné la collection du Revista Illustrada (Rio de Janeiro: numéros 402 à 666. Année de 1885 à 1893), publiée par Angelo Agostini. Notre but est d'enquêter et de comprendre, d'une part, le rôle de la presse périodique du XIXe siècle dans les processus de production, circulation et de diffusion de textes entiers, fragmentés et adaptés tout au long des éditions du Revista Illustrada, et, d'autre part, vérifier comment cette mécanique de production / circulation / diffusion a entrainé les gestes de lecture des événements historico-politiques de la société brésilienne de la fin du XIXe siècle. Nous croyons que notre recherche au-delà et au-delà boire dans la source théorique proposée par Maingueneau concernant « l'énonciation aphorisante » ou des phrases sans texte, peuvent contribuer au développement de cette théorie, puisque notre corpus, différemment de celui utilisé par le théoricien français, est de nature historique.
A dinâmica das políticas de saúde e de assistência social no Brasil : incrementalismo e pontuações na atenção governamental entre 1986 e 2003
(Universidade Federal de São Carlos, 2017-10-20) Brasil, Felipe Gonçalves; Capella, Ana Cláudia Niedhardt; https://lattes.cnpq.br/5810332148425938; https://lattes.cnpq.br/2390988873671777
This thesis analyzes the process of policy agenda setting focused on changes in health and social assistance policies in Brazil between 1986 and 2003. By mapping and analyzing the attention of actors and institutions involved in this policy process, we try to demonstrate moments of both balance and incremental change, as well as moments of rapid and profound changes in the chosen sector policies. Known in the public policy literature as the policy dynamics analysis, this thesis is based on the theoretical and methodological precepts of the Baumgartner and Jones (1993, 2005) Punctuated Equilibrium Theory. To do so, six types of documents were selected to analyze policymakers' attention: the legislative production approved in the period, messages to the National Congress sent annually by the Presidency of the Republic, minutes of the Subcommittee on Health, Assistance and Environment of the National Constituent Assembly of 1987, the Federal Constitution of 1988 and the reports of the National Conferences of Health and of Social Assistance realized within the temporal period of this thesis. In all, 23.174 data reflecting the attention of these actors on health and social care policies have been mapped, treated and analyzed in relation to their frequency, diversity and concentration over time. The thesis identifies the existence of institutional and cognitive frictions that constitute a propitious environment for changes during the first decades of Brazilian re-democratization. It also displays that variations in the attention of the actors can highlight moments of inflection and changes in policies. Still in the more general aspect, it puts in evidence the relation of the political, economic and social context and political turnovers with changes in attention on policies, sometimes leading to changes in public policies. The analysis of sector health and social assistance policies shows that, despite thematic proximity, these policies operate in distinct subsystems and focus the attention of decision makers independently. When analyzing health and care policies individually, this thesis confirms the existence of incremental moments, adjustments and small changes, but also points to changes that are specific and of great impact in both sectors. Finally, the paper reaffirms the importance of applying the Punctuated Equilibrium Theory as a theoretical and methodological basis for the study of agenda setting, policy change and policy dynamics, with this, opens a promising research agenda in this field of knowledge.
Aviação agrícola no Brasil: caracterização, invisibilização e debates
(Universidade Federal de São Carlos, 2017-10-20) Mhereb, Gabriel de Araujo; Norder, Luiz Antonio Cabello; https://lattes.cnpq.br/0080353709980071; https://lattes.cnpq.br/0374754009716272
The aerial spraying of pesticides, carried out mainly by the agricultural aviation sector in Brazil, is defended by part of society as a fundamental technology for contemporary agricultural crops to increase production; on the other hand, institutions, researchers, NGOs and social movements related to the field and health are opposed to its use, due to its high hazard and to the accidents recorded, thus proposing its prohibition. From the controversy involving aerial spraying establishment, this study aims to develop a context and a characterization of the agricultural aviation sector in Brazil, going back to the modernization of the field and the emergence of agricultural aviation; it also presents a characterization of this sector based on available information on the area that is served, the evolution of the fleet and the accidents recorded. It will also be analyzed the main informational systems on poisoning by pesticides in Brazil, the data on intoxication related to the set of pesticides, as well as the instruments of information collection, focusing on the investigation/evaluation sheets used for the notification of human intoxication, investigating the existing bottlenecks in data collection involving the aerial spraying of pesticides. Public manifestations caused by agricultural aviation will be exposed, identified and subdivided by different social fields: the scientific field, the field of social movements and the media field. The results show that the agricultural aviation sector is expanding in Brazil, due to the increasing in the fleet of airplanes, service providers distributed throughout the country and also in the sprayed area. It is shown that agricultural aviation has considerably higher accident rates than other civil aviation segments. There is also a limitation in the form of registration of the official information and in the records presented by the organizations of the sector and also by the notification systems of intoxications. Through the manifestations reported, it was demonstrated that despite the absence of official data, there is an expressive set of reports of institutions and people living and/or working in rural and urban environments on the impacts of this sector.