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Perovskitas óxidas para aplicação eletroquímica e fotovoltaica
(Universidade Federal de São Carlos, 2019-07-26)
Dias, Jeferson Almeida
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Morelli, Márcio Raymundo
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https://lattes.cnpq.br/0172837599844991
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https://lattes.cnpq.br/8402138016291171
This work aimed to investigate the production of lanthanum perovskites LaCoO3 and LaFeO3 in the form of thin films and to evaluate their use as catalysts for water splitting as well as absorbers for photovoltaic devices. That is, focusing on renewable energy. For such, the conventional polymeric precursor method was applied in the deposition of films, being improved with different polymer modifiers (amphiphilic copolymer Pluronic P123 and polyethylene glycol) – aiming to produce oxide films with greater homogeneity and enhanced morphological properties. Particularly, the combination of the polymeric precursor method and the amphiphilic copolymer Pluronic P123 is new in the literature for thin films deposition and is the greatest novelty of this work. Results demonstrated that the traditional polymeric precursor method was efficient in perovskite production with promising electrocatalytic activity. However, the produced films lacked homogeneity. On the other hand, the amphiphilic copolymer and resin combination allowed more effective spreading over the substrate. Therefore, films that are much more homogeneous, reproducible and with lower level of defects were obtained. The polyethylene glycol altered film rugosity, enhancing its catalytic activity. The photovoltaic devices built, in specific configurations, proved to be photosensitive – confirming the potentiality of the studied oxide perovskites for optoelectronic applications. Hence, results indicated that the lanthanum-based oxide perovskites are favorable for these applications and can be produced quite simply in the form of thin films using deposition strategies by solution improved in this study.
Integração entre normas de gestão da qualidade em uma empresa fornecedora da cadeia nuclear
(Universidade Federal de São Carlos, 2019-07-26)
Campos, Renato Augusto
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Guimarães, Márcia Regina Neves
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https://lattes.cnpq.br/9250214706491925
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https://lattes.cnpq.br/0916306980831101
Nuclear supplier organizations, due to regulatory requirements, pioneered the implementation of quality assurance programs in Brazil. CNEN NN 1.16 is a national standardization standard aimed at determining the requirements in the establishment and implementation of quality assurance systems in nuclear installations. On the other hand, ISO 9001: 2015 is the main ISO 9000 family standard, has quality management system requirements and aims for certification. In June 2018, ISO 19443 was published, which applies the principles of ISO 9001, combining best quality practices with specific requirements of the nuclear industry. Considering the advantages of integrating management systems, this research aims to analyze the benefits and difficulties in integrating CNEN-NN-1.16 and ISO 9001:15 standards in a nuclear chain supplier company. It is also a research objective to analyze which benefits that ISO 19443 can bring to this integrated system. The research, exploratory and qualitative in nature, used as a method of procedure the case study. Data collection was done through interviews, document analysis and participant observation. Among the results, it is noted that CNEN-NN-1.16 was published in 1999 and underwent a review in 2000, so the research demonstrates that a new revision is necessary, based on the requirements of NBR ISO 9001: 2015 and ISO 19443, such as: risk management, stakeholder management, organizational context. By critically analyzing these requirements, their potential contribution to CNEN-NN-1.16 is believed. In the organization studied, it was found that the integrated use of standards can bring benefits, however, during the implementation of NBR ISO 9001:15 and CNEN-NN-1.16, problems related to lack of training, level of worker commitment were noticed and resistance to change. These problems diminished and tended to die out as the system matured.
Modo reprodutivo de acessos de Paspalum spp. (grupo informal Plicatula) e busca de marcadores moleculares associados a apomixia
(Universidade Federal de São Carlos, 2019-07-26)
Gonçalves, Tiago Maretti
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Vigna, Bianca Baccili Zanotto
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https://lattes.cnpq.br/1663784979286725
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Fávero, Alessandra Pereira
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https://lattes.cnpq.br/4329892306148506
Belonging to the grass family, the genus Paspalum has more than 350 species, many of them with great forage potential or for use as vegetation. The Paspalum Germplasm Bank (GB) of Embrapa Pecuária Sudeste enables research with the genus and currently has about 450 accessions of 50 species, most of them belonging to the Plicatula group. Many of the Paspalum accessions of this group are tetraploid (2n = 4x = 40) and of apomitic behavior, and sexual genotypes are rare. Identifying only accessions with apomitic reproduction mode in a collection limits the breeding program because there is no possibility of hybridization. To circumvent this situation, diploid and sexual genotypes must be polyploidized for use in intra and interspecific crosses. Thus, reproductive characterization in Paspalum is of great importance, since it enables the identification of sexual genotypes and facilitates the choice of potential parents for genetic improvement. In this context, the objective of the present work was to reproductively characterize 137 Paspalum accessions belonging to the informal Plicatula group conserved in the Paspalum GB of Embrapa Pecuária Sudeste by the use of flow cytometry and cytoembriological analysis and search for molecular markers associated to apomixis. After analysis of the data obtained by flow cytometry, 49 accessions were considered highly apomictic, 85 were facultative apomictics and one accession (BGP 272 - P. rojasii) showed behavior compatible with the sexual reproductive mode. In addition to these results, the flow cytometry technique made it possible for the first time to characterize the reproductive mode of 12 accessions belonging to P. rhodopedum species. By cytoembriological analysis, five accessions were characterized, three sexual accessions (BGP 281 - P. lenticulare; BGP 272 - P. rojasii and BGP 380 - P. compressifolium) and two accessions (BGP 232 - P. plicatulum; BGP 178 - P. compressifolium) characterized as highly apomictic and facultative apomictic, respectively. In the molecular part, an association for apomixis was sought with the use of 1 marker p779/780, described as completely linked to apporia in B. decumbens, two RAPD (Random Amplified Polymorphic DNA) and 19 SCAR (Sequence Characterized Amplified Region) previously associated with apomixis in the genus Paspalum and, based on the Bulk Segregant Analysis methodology, 51 nuclear microsatellite markers were genotyped, totaling 73 molecular markers evaluated in P. compressifolium and P. lenticulare sexual and apomitic accessions. For SCAR markers, accessions belonging to P. rojasii were also included. A large polymorphism occurred between the samples, but no link was observed between the apomixis characteristic and the molecular markers evaluated. The present study shows a greater reproductive genetic variation among the characterized accessions, there was a correspondence between the ploidy level and the reproduction mode, as expected, and none of the genotyped molecular markers were linked to apospory in the evaluated germplasm. Thus, this study presented important results that could be applied to the selection of parents in Paspalum breeding programs.
Atividades de modelagem matemática com equações de diferenças
(Universidade Federal de São Carlos, 2019-07-26)
Lima, Antonio Augusto de
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Salvador, José Antonio
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https://lattes.cnpq.br/2487171069472158
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https://lattes.cnpq.br/5709334677028791
Teaching math subject in basic education is a big challenge. Once the teacher is successful, the great value to be cultivated is to present students with meaningful content. Nowadays, in many cases, teaching of mathematics is restricted to “learning by heart”, and in this sense we propose a work based on the autonomy to manage their own learning in Modeling Activities. The approach among the school contents and the valorization of the contextualization, connected to the great importance of the use of the computer room was our starting point. In this perspective, mathematical modeling is a mechanism that can be easily associated with some content that makes up the curriculum of the discipline in order to improve the teaching-learning process. Thus, in this work, a discussion is implemented about how mathematical modeling can be worked in line with the study of the difference equations, with the aim of bringing formal mathematics closer to everyday mathematics and, futhermore, bringing the student closer to their reality.To this end, a thorough bibliographic research was carried out in collections of renowned authors in the area of Mathematical Modeling, Functions and Mathematics Teaching-Learning, which enabled the formation of a consistent theoretical foundation for the development of this research, as well as intervention in a class. High School in an elective subject offered by the researcher in a Full Time School. Finally, it was verified the significance of the mathematical modeling approach associated with the contents of the High School curriculum, especially the content of difference equations, and at a given moment, by curiosity of the students, the quadratic function, in the condition of mechanisms. mathematicians capable of developing unique skills in students such as abstraction and logical reasoning.
Proposição de modelos de classificação e de calibração para polímeros presentes em resíduos eletrônicos empregando laser-induced breakdown spectroscopy (LIBS) e ferramentas quimiométricas
(Universidade Federal de São Carlos, 2019-07-29)
Costa, Vinicius Camara
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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/6162409795305177
This thesis proposes the development of analytical methods for the analysis of polymers from waste electrical electronic equipment (WEEE) by laser-Induced breakdown spectroscopy (LIBS). The results presented in the chapters 2 and 3 of this thesis were developed in collaboration with a recycling company of WEEE called REVERSA. In the first method proposed LIBS was used for the identification and classification of six polymers and a total of 477 samples were analyzed. Classification models using k-nearest neighbors (KNN) and soft independent modeling of class analogy (SIMCA) were used to classify the polymers. The proposed models presented satisfactory results for the validation samples, with accuracy of 98% for KNN and 92% for SIMCA. In addition, other validation parameters such as sensitivity, false alarm rate and specificity showed adequate. In the second method, the LIBS was employed to determination of the constituents polycarbonate (PC) and acrylonitrile-butadiene-styrene (ABS) in PC/ABS blends. For this were built multivariate calibration models using partial least squares (PLS). The PLS models obtained for the PC and ABS presented good analytical parameters as: i) standard error calibration (SEC) of 3.4 (w/w%); (ii) standard error of cross-validation (SECV) of 5.6 (w/w%); iii) linear correlation coefficient of 0.996; iv) number of latent variables equal to 2; v) explained variance of 70%. For the validation of the PLS models PC/ABS blends with unknown concentrations of PC and ABS were analyzed, and the information provided by LIBS was in agreement with the reference technique. A third method was developed in collaboration with a plastics recycling company of car batteries. These plastics were contaminated with Pb and the objective was to evaluate different calibration strategies in LIBS for the quantitative determination of this analyte. Multivariate calibration strategies and a new univariate strategy were proposed. The new univariate calibration strategy was called a two-point calibration transfer and the results presented were satisfactory. The chemometrics tools including experimental desing, supervised methods for classification, unsupervised methods and multivariate calibration were employed during the development of the methods proposed in this thesis.
Taxonomia, ecologia e distribuição espacial de rotifera no estado de São Paulo
(Universidade Federal de São Carlos, 2019-07-29)
Ribeiro, Tainá Alves
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Rocha, Odete
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https://lattes.cnpq.br/7577441794992601
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https://lattes.cnpq.br/5531769361645809
Rotifers inhabit a variety of aquatic habitats. It is thought that the success of this group is largely due to their small size, short life cycle, ang high richness of species, being these aspects largely responsible for the species richness of zooplankton communities in freshwater ecosystems. The aim of this study was to evaluate the taxonomic composition of rotifer communities in different types of freshwaters of São Paulo state, distributed in 22 Management unities of water resources (UGHRI). Zooplankton communities of 283 water bodies were sampled by horizontal net hauls. In situ measurements of pH, electrical conductivity, temperature and O2 concentrations were performed and water samples were simultaneously taken for laboratory measurements of chlorophyll a concentration. Based on chlorophyll concentration values, the trophic state index (TSI) was calculated and water bodies were then classified in one of six categories regarding their trophic degree. A total of 113 species of Rotifera, belonging to 20 different families were recorded. Families with highest species richness were Lecanidae, Brachionidae and Trichocercidae, following a pattern already described for tropical region rotifer communities. The species with highest frequency of occurrence were Lecane bulla, ocurring on 70% of all water bodies sampled and Lecane leontina, with 35,9%. There was a significant linear relationship between the number of water bodies sampled in each management unity and their rotifer species richness. It was also verified a low positive correlation, but statistically significant between species richness and the trophic state of the water bodies. There were evidences that the spatial distribution pattern observed for rotifers was influenced mainly by physical and chemical characteristics and trophic state of the water bodies. There are indicatives that differently from the pattern frequently observed for microorganisms, the distribution of most species can be restricted more by tolerance limits regarding environmental variables than by their dispersal capacity.
Detecção de novidade em fluxos contínuos de dados multirrótulo
(Universidade Federal de São Carlos, 2019-07-29)
Costa Júnior, Joel David
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Cerri, Ricardo
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https://lattes.cnpq.br/6266519868438512
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https://lattes.cnpq.br/5293958366030922
Multi-label Stream Classification (MLSC) aims at classifying streaming examples into multiple classes simultaneously. It is a very challenging task, since new classes may emerge (concept evolution), and known classes may change over the stream (concept drift. Most of classifier methods deal with the aforementioned characteristics updating their models when actuals labels of examples become available, it is a very optimistic scenario though, since for many data streams application these labels are never available, hence is unfeasible to update models in a supervised fashion. This is known as infinitely delayed labels problems and a task that has been stood out for dealing with it, is the Novelty Detection (ND). ND aims at detecting new patterns in arriving streaming examples that, in some aspect, might differ from the previously observed patterns and then used for updating the decision models. Despite different ND procedures have been proposed in the literature, it is still an open problem for MLSC. In this work we proposed two new methods: the MultI-label learNing Algorithm for data Streams with Label Combination-based methods (MINAS-LC) which applies ND to deal exclusively with concept drifts and the MultIlabel learNing Algorithm for data Streams with Binary Relevance transformation (MINAS-BR) which applies ND to deal with both concept drifts and concept evolution either. The methods address problem transformation techniques to deal with multi-labelled data at the offline phase and build micro-clusters based decision models. At the online phase the arrival examples are classified or rejected (labelled as unknown) by the current decision models. Rejected examples are used in ND phase to shape new micro-clusters, maintaining the decision models updated. The ND phase is run from time to time to work around concept drifts and concept evolution. Experiments over synthetic and real-world data sets with different degrees of concept drift and concept evolution attested the potential of MINAS-BR and MINAS-LC, in which have obtained significant results when compared to baseline methods.
Princípios e fundamentos teóricos da catalogação descritiva e a proposta do Resource Description and Access (RDA)
(Universidade Federal de São Carlos, 2019-07-29)
Machado, Raildo de Sousa
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Zafalon, Zaira Regina
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https://lattes.cnpq.br/1584935790390793
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https://lattes.cnpq.br/9586215965015886
Cataloging codes are the subject of research, and Resource Description and Access (RDA) is their object of study. In the course of the research, it is questioned about the relation of the principles and fundamentals of cataloging with the proposal of the RDA. To this end, the general objective seeks to discuss the RDA proposal in the light of the principles and foundations of descriptive cataloging. The specific objectives have [1] map scientific discussions about the RDA; [2] analyze the founding theorists of cataloging, its principles and foundations; [3] present the history of cataloging codes and treaties; [4] present the basic conceptual models of contemporary cataloging; [5] analyze the RDA, its principles and objectives; [6] present the theoretical and practical movement from the publication of the RDA, which objectives will lead to understand the past, present and future of the RDA and how it appropriates the principles and foundations of descriptive cataloging. The applied research adopts a qualitative approach, making use of systematic literature mapping as part of the bibliographic and documentary procedures to achieve the exploratory and descriptive objectives. Academically, it is intended to contribute to discussions about the essence of the RDA, by expanding the possibilities of studies and familiarity with the objectives, principles, functions and application of the RDA standard. This research is justified in the context of Information Science because it is the organization and representation of information and, in the scientific contribution, brings trends on the subject as a result of the literature mapping.
Cônicas: uma prática escolar
(Universidade Federal de São Carlos, 2019-07-30)
Puppin, Maurício
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Bertoncello, Luciene Nogueira
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https://lattes.cnpq.br/8028970771846775
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https://lattes.cnpq.br/7328458570509096
Based on the protagonism of the learner, this work aims to assist the teacher of mathematics of High School, in the teaching of Analytical Geometry, with a practical approach to facilitate the student's understanding of Conics, with emphasis on ellipse. By the use of free software Geogebra, the student can observe the translation of the curve in the plane and identify in its equation, the differences between the positions: horizontal and vertical, making learning dynamic and more effective.
Desenvolvimento de membranas poliméricas para sistemas de remediação de íons metálicos pesados em soluções aquosas
(Universidade Federal de São Carlos, 2019-07-30)
Bosquetti, João César
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Silva, Caio Marcio Paranhos da
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https://lattes.cnpq.br/7793686262868668
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https://lattes.cnpq.br/1261532663035588
The planet Earth is flooded with about 1.4 billion km3 of water, meaning that almost 71% of its surface is covered by water. However, only about 0.77% of this volume is accessible in the form of fresh water presented in rivers, lakes, groundwater and the atmosphere. Meanwhile of this small amount, about 12.8% have been contaminated or poorly used by man. This contamination is usually caused by percolation, whether of spot or diffuse, such as accidents in reservoir tanks, discharge of sewage sludge, improper use of fertilizers and sanitary waste, as well as accumulation of waste on riverbanks, has been increasing in last years. Contamination of water by heavy metals is perhaps the most worrying of contaminations, since they are highly toxic, cumulative and difficult to mitigate. In this sense, considering the amount of residues generated in the Laboratory of Teaching of Inorganic Chemistry, contaminated with heavy metals of high toxicity, it was thought of a way to reduce the amount of ions of some metals, especially lead (Pb), cádmium (Cd) and Mercury (Hg), employing low cost and easy to obtain polymer membranes to minimize the amount of waste sent to the Department of Waste Management (DeGR) of the Federal University of São Carlos - UFSCar. The aim is to minimize these ions present in the solutions, bringing the possibility of reuse of previously contaminated water or to discard it in the common domestic sewage, depending on the efficiency generated by the adsorption yield of these membranes in removing these inconvenient ions from the aqueous solution of discard. Basically, high density polyethylene (HDPE) membranes were modified with polyethylene with maleic anhydride (PE-g-AM), loaded with sodium aluminate and incorporated with aluminum phosphate (AlPO4). Membranes were synthesized whose proportions of these materials were varied with the purpose of verifying which of them would give the best yield. In this aspect, it was observed that all the membranes and blends synthesized showed heterogeneity in their constitution, resulting in regions with higher and lower yield in the same membrane. However, the blends loaded and incorporated with aluminum phosphates had a slightly higher adsorption efficiency compared to ions dispersed in the solution.
Mechanical properties and metallurgical characterization of AA6082-T6 alloy welded by refill friction stir spot welding
(Universidade Federal de São Carlos, 2019-07-30)
Silva, Bruno Hessel
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Zepon, Guilherme
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https://lattes.cnpq.br/7924187202036614
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Bolfarini, Claudemiro
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https://lattes.cnpq.br/9231627080617037
The efforts to produce automobiles with intense use of aluminum alloys is growing and the 6XXX series of aluminum alloys are important for this scenario. However, the current joining technologies applied in these alloys present limitations regarding weld uniformity, energy input and production costs. Refill Friction Stir Spot Welding (RFSSW) is a solid-state welding technique with potential to surpass these limitations. In order to validate this technique in automotive applications, issues must be addressed such as obtaining mechanical properties standards; determining the effect of process parameters on weld structure and properties; optimizing cost-efficiency factors and others. In this work the application of RFSSW in the AA6082-T6 alloy was studied focusing on: (i) the effect of process parameters on weld structure and mechanical properties; (ii) understanding of fracture behavior of the welds under static and cyclic load; and (iii) the influence of Bake Hardening treatment on the weld structure and properties. Optimized process parameters set with suitable welding time for industry applications were obtained using statistical analysis maximizing static mechanical properties. Macro/microstructural analysis were carried out and demonstrated that the Plunge Depth parameter has the most relevant influence on weld strength and fracture behavior due to its effect in hook shape formation, which is an intrinsic feature in RFSSW welds. Hardness and thermal characterization helped to understand the effect of Bake Hardening on reprecipitation and overaging process in different weld regions and, consequently, on the mechanical properties and fracture behavior of the welds. Using Weibull Statistical analysis, L-N fatigue curves were obtained and demonstrated that, regardless the hook shape, the curves presented similar trend and fatigue limit close to 12% of the maximum Shear Load. Finally, based on fatigue fracture surface characterization, it was found that the hook shape configuration has a relevant effect on fracture behavior only for low-cycle load conditions.
Existence and multiplicity of solutions for problems involving the Dirac operator
(Universidade Federal de São Carlos, 2019-07-30)
Somavilla, Fernanda
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Miyagaki, Olimpio Hiroshi
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https://lattes.cnpq.br/2646698407526867
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Paiva, Francisco Odair Vieira de
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https://lattes.cnpq.br/2889322093175193
In this thesis, we study equations that involving the Dirac operator and which have the form $-i \alpha \cdot \nabla u + a \beta u + M(x)u = F_{u}(x,u), em \mathbb{R}^{3},$ where $\alpha = (\alpha_1, \alpha_2, \alpha_3),$ with $\alpha_{j}$ and $\beta$ are complex matrices 4x4, j = 1, 2, 3 and a>0.Using variational methods and elements from critical point theory for strongly indefinite problems we obtain existence and multiplicity results of solutions $u:R^{3} \rightarrow C^{4}$ under different sets of hypothesis about the potential M and the nonlinearity F: Firstly, we consider a problem with nonperiodic potential and concave-convex type nonlinearity, nonperiodic, which contain weight functions that can present signal change. Next, using the generalized Nehari manifold, we study problems in which nonlinearity satisfies weak monotonicity conditions and may relate to the potential function. Among such problems,we consider a periodic case and, due to the assumptions, in order to obtain the multiplicity results we use the Clarke's subdifferential and Krasnoselskii genus. Finally, we approach a problem with nonlinearity asymptotically linear at infinity and matrix potential. In this case, the potential is described by a sum of a non-positive suitable matrix potential and a diagonal matrix whose elements are function in some $L^{\sigma}, \sigma >1,$ which can change signal.
Proposição de modelos de regressão para previsão de propriedades de tintas da cadeia produtiva da indústria gráfica
(Universidade Federal de São Carlos, 2019-07-30)
Oshiro, Eduardo Hideki
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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/9220595873630980
Quality control of inks is very important during and after the manufacturing process and is also meaningful in the consumer industries or paint applicators. For this reason, an opportunity was noticed for the development of a method of determining the properties of a solvent based ink of the printing industry. The analytical method proposed was through the infrared spectroscopy and multivariate calibration. The ink used in the project is employed in the rotogravure printing process. This process is used for printing many quantities of printing materials at high speed. It is usually applied in the production of packaging and magazines. The fallowing quality control parameters: viscosity, density and solids of black and white inks were analyzed by the reference methods according ASTM standards. Prediction models for these parameters were developed through Fourier transform infrared spectrometer with attenuated total reflectance sampling accessory (FT-MID-IR ATR) and the multivariate calibration, the partial least squares regression (PLSR). Pre-treatments in the spectra (1st and 2nd derivatives with Savitzky-Golay) were tested and also the models with spectra without treatments. The best results were found according to the parameter and ink tested, for viscosity of black ink the model without treatment was used, for viscosity of white ink the 2nd derivative was used. And for density and solids, unique models were developed to be used in black and white inks, the 1st derivative was the best option in both cases. The best models and latent variables were selected through the evaluation of the root mean square errors values of calibration, validation and cross validation (RMSEC, RMSEV and RMSECV), as well as the determination coefficients (R2) obtained from predicted x reference results. The set of validation samples showed a good quality of the results, according to the p-value. Although there are many articles related to prediction of chemical physics characteristics of fuels and derivatives using infrared spectroscopy and the chemometric tool, few studies with this approach to inks have been found in the literature. The following advantages of the developed method can be highlighted: low sample volume (0.1 mL - 1 drop), rapid analysis (2 minutes) and the low waste amount.
Síntese do catalisador ácido molibdofosfórico suportado em zircônia sulfatada e magneticamente recuperável visando a valorização de compostos derivados da biomassa lignocelulósica
(Universidade Federal de São Carlos, 2019-07-31)
Marchini, Lucas
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Paixão, Márcio Weber
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https://lattes.cnpq.br/3773908504964104
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https://lattes.cnpq.br/6978772339322590
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https://orcid.org/0000-0002-6349-5181
The impacts associated with excessive use of energy derived from non-renewable sources transcend the discussion of possible exhaustion and are strongly aligned with the possibility of an environmental imbalance. In this way, the interest in the production of fuels from natural and renewable sources grows strongly throughout the globe. In this directenvironmentalsting paths for sustainable fuel growth and development is through the use of lignocellulosic biomass as the raw material. Lignocellulosic biomass represents a high interest due to the possibility of being converted into sugars which, in turn, proceeds through reactions catalyzed by acid - Lewis and Brønsted - to provide products such as furfural (FUR), 5-hydroxymethylfurfural (HMF), levulinic acid (LA), alkyl levulinate, gamma-valerolactone (GVL) and derivatives thereof. These compounds are considered platforms molecules of great industrial and academic interest. Therefore, it is of great importance the research of new materials with acidic characteristics, which are able to promote these transformations.The molybdophosphoric acid (MoP) is a heteropolyacid that has associated protons, presenting high Brønsted acidity and, consequently, emerges as an interesting catalyst in the valorization of compounds derived from lignocellulosic biomass. In this work, a catalyst composed of molybosphoric acid supported in magnetically recoverable sulfated zirconia was synthesized, which should be characterized by techniques such as X-ray diffraction (XRD), programmed temperature desorption of ammonia (TPD-NH3), transform infrared spectroscopy of Fourier with adsorption of pyridine (FTIR-py), quantum interference superconducting device (SQUID), X-ray photoelectron spectroscopy (XPS), 31P nuclear magnetic resonance, transmission electron microscopy (TEM), and high transmission electron microscopy resolution (HR-TEM). Properly characterized, they were evaluated the conversions of the compound derived from lignocellulosic biomass to alkyl levulinates. In the catalytic evaluation, it was necessary to optimize the catalyst through the influence of fundamental parameters such as temperature, catalyst mass, molar ratio between the substrate and solvent, and water influence in order to obtain the ideal conditions and the products of this reaction analyzed by gas chromatography coupled with mass spectrometry (GC-MS).
A riqueza do élenchos: um estudo sobre a aplicação platônica da prática investigativa socrática
(Universidade Federal de São Carlos, 2019-07-31)
Quinalia Filho, Rineu
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Souza, Eliane Christina de
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https://lattes.cnpq.br/5658382257368048
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https://lattes.cnpq.br/1710662256211660
Proposing a presentation regarding élenchos is not an easy task. Élenchos is primarily a synonym of inspection. Everything starts with a simple question: “what is?” (ti estí;). Ti estí basically establishes the relationship between the subject who applies the question (Socrates) and the other who must defend it (almost always a renowned interlocutor). At the start, élenchos has a personal character, a play of roles between someone who asks and another person who answers with fixed guidelines. Two dialogues from Plato’s youth are explored in this thesis: Laches and Charmides. Considering that these dialogues are watched by a supposed audience, we point to an interpretation where the main interlocutors of Socrates could represent a kind of stage, a means to an end, and not the final recipient of the dynamics proposed by the Socratic inspection. The thesis will establish a metaelenctic approach pointing to the interpretation that the Socratic élenchos could be seen under the light of a two-fold orientation: the first one, which is called ‘straight’, would have a dual nature, proposing the inspection of a (famous) other; the second is the ‘oblique’, with a plural nature, aiming at the instruction of (humble) others.
Influência da taxa de resfriamento no módulo de elasticidade de ligas beta Ti e obtenção de diagramas CCT
(Universidade Federal de São Carlos, 2019-07-31)
Santos, Rafael Formenton Macedo dos
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Munoz Chaves, Javier Andres
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https://lattes.cnpq.br/1205198307049324
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Afonso, Conrado Ramos Moreira
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https://lattes.cnpq.br/2176215981291453
The metallic alloys used as orthopedic implants, such as the Ti-6Al-4V, present some problems of biological and mechanical compatibility. In addition, the great difference between the elastic modulus of human bone and the commercial alloys used as implants is responsible for the stress-shielding effect. In this way, the objective of this study was to obtain CCT diagrams through dilatometry of β-Ti alloys and to investigate the influence of the cooling rate by comparing the microstructure and properties (microhardness and elastic modulus) for Ti-40Nb (Ti40Nb) and Ti-12Mo-6Zr-2Fe (TMZF) alloys. For this, besides the alloy as received, it was yield the following cooling rates: 103 oC/s for rapidly solidified (SR condition); 102 oC/s for water quenche; 5 oC/s for air cooling and 0.05 oC/s for furnace cooling. Afterwards all the samples were submitted to the microstructural characterization through X-ray diffraction (XRD), optical microscopy (OM) and scanning electron microscopy (SEM). Physical property of elastic modulus E (GPa) was measured via impulse excitation technique while the mechanical property was assessed using Vickers microhardness. Finally, the thermal characterization was performed by differential scanning calorimetry (DSC) and dilatometry. For the SR condition, which showed the lowest values of elastic modulus and Vickers microhardness, the presence of β-Ti (bcc) and α” (martensite) phases for both alloys and the values of modulus and elasticity and Vickers hardness, respectively, with 56 GPa and 144HV for the Ti40Nb (SR), 74GPa and 333HV for the TMZF (SR) alloy. For lowest cooling rate (furnace), the results showed the presence of β and α phases for both alloys, and values of E = 83 GPa and 302 HV for the Ti40Nb alloy and 106 GPa and 443 HV for the TMZF alloy. Based on these results, together with the results of the DSC test and dilatometry, it was possible to build real CCT diagram for both alloys.
Contribuição para a melhoria no desempenho ambiental de porcelanatos: Avaliação de Ciclo de Vida (ACV) e o uso de fundentes enérgicos
(Universidade Federal de São Carlos, 2019-08-01)
Contartesi, Flavia
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Melchiades, Fábio Gomes
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https://lattes.cnpq.br/4469106561041487
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Boschi, Anselmo Ortega
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https://lattes.cnpq.br/3259846931278607
Whether due to growing environmental awareness or legal and market requirements, the quest for sustainable development has leading to the need to improve processes and products. In this scenario, the general objective of the present work was to contribute to the improvement in the environmental performance of porcelain tile industries in Brazil, the third largest producer of ceramic tiles in the world, from two complementary stages. The first one, through the Life Cycle Assessment (LCA) bibliography of ceramic tiles developed in Brazil and in the world, aimed to identify the most critical stages of the manufacturing process and to raise peculiarities of the Brazilian reality. The results pointed to the firing stage as the main responsible for the environmental impacts and the use of the dry route as the most outstanding peculiarity of the Brazilian industry. From these results, the second stage aimed to contribute with proposals to reduce the most critical stage. In this context, it was proposed the reduction of the firing temperature, and consequently of the associated impacts, in porcelain tiles manufactured by dry route through the use of energetic fluxing agents. To try to predict the effects of the addition of fluxes on the behavior of the standard formulation during sintering the Fluegel viscosity model was used. The initial reduction target of 30 °C was reached for all fluxes used and exceeded in some. In the supply of alkaline earth oxide modifiers, the prediction was accurate, for alkaline, approximate. However, for borates the results differed considerably from those predicted by the model. The results showed a good correlation between the viscosity of the liquid phase and the firing temperature, suggesting that the formulations with the lowest firing temperature are able to densify without reaching viscosity as low as the standard.
Da luta pela terra ao reconhecimento: considerações sobre a trajetória das famílias assentadas no PDS Santa Helena e o acesso a políticas públicas
(Universidade Federal de São Carlos, 2019-08-01)
Khalil, Bárbara El
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Carvalho, Joelson Gonçalves de
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https://lattes.cnpq.br/4923394220818843
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https://lattes.cnpq.br/0141039743607067
A expansão do capitalismo no meio rural tem como consequência histórica o conflito entre o capital e as populações camponesas. Esse conflito se materializa, não somente, mas em grande parte, na luta pela terra e na dificuldade que as populações camponesas têm em acessar políticas públicas voltadas para um desenvolvimento rural compatível com a diversidade dos sujeitos e de suas formas de organização social presentes no rural brasileiro. Neste contexto, o presente trabalho pretende analisar a conflitualidade inerente à questão agrária brasileira a partir de um estudo de caso, a saber: o Projeto de Desenvolvimento Sustentável (PDS) Santa Helena, localizado no município de São Carlos, interior do estado de São Paulo. Nosso objetivo é reconstruir a trajetória de luta pela terra dos assentados, bem como compreender como se dá o acesso da comunidade assentada a outras políticas públicas. Nossa hipótese é a de que os agricultores do Santa Helena enfrentam dificuldades para serem reconhecidos como sujeitos que podem acessar políticas públicas, o que limita, por seu turno, a capacidade de produção e reprodução social e material desses assentados.
Modelos não lineares assimétricos com efeitos mistos
(Universidade Federal de São Carlos, 2019-08-02)
Pereira, Marcos Antonio Alves
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Russo-Novelli, Cibele Maria
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https://lattes.cnpq.br/1011098065426388
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https://lattes.cnpq.br/4792032354955226
This work aims to develop asymmetric nonlinear regression models with mixed-effects, which provide alternatives to the use of normal distribution and other symmetric distributions, in order to avoid the sensitivity in the estimates to atypical observations and asymmetry. Nonlinear models with mixed-effects are explored in several areas of knowledge, especially when data are correlated, such as longitudinal data, repeated measures and multilevel data, in particular, for their flexibility in dealing with measures of areas such as biology and pharmacokinetics. However, there are difficulties in obtaining explicit estimators for the parameters in these models. At present, many studies have been developed with the family scale mixtures of skew-normal distribution (SMSN) that encompasses distributions with light and heavy tails, such as skew-normal, skew-Student-t, skew-contaminated normal and skew-slash, as well as symmetrical versions of these distributions. In this work, nonlinear regression models with mixed-effects are presented in which the random components have distributions belonging to the SMSN family. For the parameters estimation, a numerical solution via the EM algorithm and its extensions and Newton-Raphson algorithm is obtained. Analyzes for real data sets are performed with this new proposal, such as the study of drug kinetics in humans, as well as diagnostic analyzes, through residual analysis and influence diagnostics. Simulation studies are conducted to verify the maximum likelihood properties of the estimators.
Invasor (in)conveniente: o manejo de javali como política pública
(Universidade Federal de São Carlos, 2019-08-02)
Guillardi, Bruno Luiz
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Molina, Wagner de Souza Leite
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https://lattes.cnpq.br/5939243693407420
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https://lattes.cnpq.br/3785840214023786
This master thesis aims to demonstrate the implementation of wild boar management as a State Public Policy, especially in the state of São Paulo. Thus, we seek to explain the possible causes of the introduction and spread of wild boars (Sus scrofa) within the Brazilian territory, as well as the reasons that caused their demographic growth, a fact that has caused several economic, environmental and social damages throughout the country. Faced with this scenario, the Brazilian Institute of Environment and Renewable Natural Resources (IBAMA) eventually released the management, via slaughter, as a way to try to control its proliferation. However, given the lack of resources (human and financial) of the Brazilian State, it was up to individuals and companies to take over the management of wild boars, ie, while the State would be responsible for legislation and supervision, people who wanted, for some reason. For this reason, controlling wild boars could, with proper authorization, do so. Initially, in the state of São Paulo, the person responsible for releasing and overseeing management was the State Secretariat of the Environment (SMA) through its regionalized departments. Subsequently, this changed, with IBAMA being in charge of the registration and accountability of managers, while SMA along with the police agencies would be responsible for enforcement. However, the problem lies in the changes in management laws that are being changed too much - sometimes by the state government, sometimes by the federal government -, showing that the perspectives of action of those who build the management policy, the state organs, compared to those who carry out the control, the managers are not the same. Therefore, the problem of wild boar spread may persist or even worsen. Thus, in this paper, besides just trying to demonstrate the possible beginning of the introduction of wild boars in Brazil and the probable damages caused by their proliferation, we tried to contribute with some considerations and considerations, presenting different perspectives, often conflicting, of the State legislator/inspectors and control agents, in order to better clarify the management of wild boar as a Public Policy.