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Zoneamento geoambiental da bacia hidrográfica do Rio São João (MG) como subsídio à gestão dos recursos hídricos
(Universidade Federal de São Carlos, 2019-03-08) Jacó, Ana Paula; Collares, Eduardo Goulart; https://lattes.cnpq.br/3131900230122094; Lorandi, Reinaldo; https://lattes.cnpq.br/7794241793056671; https://lattes.cnpq.br/5165885895964931
Considering the importance of the preservation and sustainable use of water resources nowadays, in the face of accelerated social and economic development, this work represents an important tool of direct contribution in the environmental and water resources management of the São João River Watershed (BH-SJ), which presents a drainage area of 2,417.7 km² and is located in the southwest of the state of Minas Gerais, Brazil. This basin is characterized by its diversity and intensity of anthropic interventions, which affect (directly or indirectly) its water regime. The geo-environmental investigation, associated to zoning techniques, stands out as an essential tool to subsidize planning and management of land-use. In this context, using Geo-environmental Zoning (ZG) techniques and data cross checking, this work sought to elaborate and interpretative cartographic documents as a form of subsidy to the territorial planning and management of the water resources of BH-SJ, based on an integrated diagnosis of its water availability and demand. Among the cartographic documents elaborated, the following stand out as the main ones: Letter of Surface Water Availability; Letters of Surface and Subterranean Water Demand; Letter of Punctual Anthropogenic Actions and the Geo-environmental Zoning Charter for the BH-SJ Water Stress Potential. These documents were elaborated in a scale of 1: 50,000 in the GIS environment (Geographic Information Systems) from the mapping and crossing of intermediate data classified as geo-environmental attributes. The results obtained in the Letters of Water Availability and Demand show the features of BH-SJ that present the largest and the smallest occurrences of these two components, highlighting the areas according to their priority levels. Similar terms were used to classify the occurrence of the components: Very Low, Low, Medium, High and Very High. The Letter of Punctual Anthropogenic Actions illustrates that the consumptive uses of water resources in the watershed can go well beyond the estimated values due to the intensity of occurrence and the deficiency in the user registry by the competent bodies. The ZG Chart on Water Stress Potential was elaborated from the intersection between the water availability and demand results. From the subdivision of the study area in Microbasins (Mbs), the diagnosis of water stress potential in 581 Mbs was obtained and presented the following classification: Very Low (17Mbs); Low (344 Mbs); Medium (146 Mbs); High (70 Mbs); Very High (4 Mbs). The Mbs classified with high and very high potential of water stress are characterized by the high index of anthropogenic interventions in their water resources, in this way they fall into the class of high priority for measures that aim to improve the management of use in these places. Therefore, the results of this research represent an effective tool to subsidize the decision management and support, considering the feasibility of integrated analysis of the territory of BH-SJ, aiming at the sustainable use of water resources and the prevention or mitigation of possible conflicts of use in the areas that present the greatest potential to the water stress generated by the excessive use of this resource.
Síntese e caracterização de hidrogel para processo de fracionamento da lignina extraída do bagaço de cana-de-açúcar
(Universidade Federal de São Carlos, 2019-03-08) Rodrigues, Jéssica; Botaro, Vagner Roberto; https://lattes.cnpq.br/2907189124654066; https://lattes.cnpq.br/4368023496052703
Brazil is currently considered the largest producer of sugarcane in the world, which results directly in tons of lignocellulosic biomass residues. The use and recycling of these process residues would reduce the environmental problems associated with improper storage in nature, add value to the constituents of lignocellulosic materials and reduce the use of fossil fuels. The objective of the present work is to separate lignin fractions extracted from sugarcane bagasse in preparative scale gel permeation chromatography (GPC), containing as a stationary phase the hydrogel (HEDTA) derived from cellulose acetate (AC) and ethylenediaminetetraacetic acid dianhydride (EDTAD). The acetosolv pulping was used for the extraction of the lignin present in sugarcane bagasse, using acetic acid as solvent, hydrochloric acid as catalyst and water at the boiling temperature of the mixture. For the synthesis of HEDTA, the AC and EDTAD were solubilized in dimethylformamide (DMF), and triethylamine was used as the reaction catalyst for esterification and crosslinking between free hydroxyl groups of CA and EDTAD. After the curing period, HEDTA was neutralized, milled and sieved to obtain 35 mesh size particles. HEDTA was swollen with tetrahydrofuran (THF) before being packed in the fractionation column and the previously prepared lignin solution was passed through the separation column to generate different fractions of lignin moieties. The HEDTA and extracted lignin samples were characterized by the following techniques: Fourier Transform Infrared Spectroscopy (FTIR), GPC, Thermogravimetric (TG) and Scanning Electron Microscopy (SEM). For HEDTA, density analysis was also performed by pycnometry. The lignin fractions were characterized by GPC and FTIR. In the FTIR spectrum of lignin, the 1594 cm-1 stretching, attributed to the stretching of the aromatic skeleton CC and C = O stretching, and the stretching at 1511 cm -1 relative to the vibrations of the aromatic rings, together prove that the structure lignin was preserved after the acetosolv pulping process. The FTIR spectrum of AC and HEDTA demonstrate the esterification reaction between EDTAD and the free hydroxyls present in AC. HEDTA had a density of 1.344 g/cm3. The MEV characterization of AC and HEDTA found that they are visually similar. The fractionation of the lignin acetosolv sample (LA), lignin acetosolv hydrolyzate (LH) and phenol (EF) occurred according to its hydrodynamic volume, as evidenced by the GPC technique. The first fractions showed no GPC curves and no FTIR bands characteristic of phenol, proving their selective fractionation. Concluding that the applicability of HEDTA as stationary phase in GPC on a preparative scale has been proven.
Adaptação em língua portuguesa do Functional Acquistion Speed Test (FAST) para estudar estereótipo de gênero no Brasil
(Universidade Federal de São Carlos, 2019-03-08) Marcelino, Madeleine Reinert; Arantes, Ana Karina Leme; https://lattes.cnpq.br/1785475312488456; Reis, Maria de Jesus Dutra dos; https://lattes.cnpq.br/8868678989340770; https://lattes.cnpq.br/8099013130438322
We can measure attitudes explicitly, using self-report instruments, and implicitly, through tasks in which participant’s performance in tests of relations between stimuli is measured. The Functional Acquisition Speed Test (FAST) has been used to access implicit measures of gender stereotypes through a procedure that consists comparing the participant's learning curves in two blocks of trials: a block in which a response (clicking on the same key) is reinforced in the presence of any stimulus from a set of stimuli considered to be consistent (eg, the “Z” key for “male” and male traits such as “dominant” and “M” for “woman” and traits considered feminine, as “sensitive”); and another block in which a response is reinforced in the presence of stimuli belonging to a set considered inconsistent (eg, “Z” for “man” and “sensitive” and “M” for “woman” and “dominant”). Experiment 1 aimed to select Portuguese words suitable for use in FAST with Brazilian population, seeking both adjectives that flex in gender and neutral adjectives. In Experiment 2 we evaluated difference in participant’s performance in FAST with the words chosen in Experiment 1 in four different conditions that assessed two different forms of presentation for words that flexed in gender. We also evaluated decrease in the maximum response time (from 3s to 1.5s) influence. Words in Condition 1 was gender-neutral and 3s maximal response time. In Condition 2, we used words that flex in gender, with an undeline in place last word’s letter and 3s of maximum response time. In Condition 3, we used neutral words in gender and 1.5s of maximal response time. In Condition 4, we used words that flexed in gender, presenting them inside boxes and keeping the last one empty, giving a maximum response time of 1.5s. Results showed significant difference only between conditions 1 and 2, and between conditions 1 + 3 and 2 + 4, analyzed together. Data indicates there is no difference between the use of 3s or 1,5s as the maximum response time in the neutral words. We presented additional discussion on variables of interest and other experimental controls
Conhecimento e monitoramento metacognitivo em tarefas que envolvem criatividade
(Universidade Federal de São Carlos, 2019-03-08) Deffendi, Luma Tiziotto; Schelini, Patrícia Waltz; https://lattes.cnpq.br/6185333517392859; https://lattes.cnpq.br/1201862251605595
Metacognition can be understood as the knowledge the individuals have about their own cognitive processes and that allows the monitoring and regulation of their cognitive activities. From the cognitive point of view, creativity is the name given to a group of processes that tend to facilitate the elaboration of new and unprecedented forms of grouping. The aim of this thesis was to approach, in an integrated way, the relationship between the two contours: metacognition and creativity, considering that such interaction isn´t explored in the scientific scene, especially in the national scene. The thesis was organized in three manuscripts in order to facilitate the understanding of the general objective mentioned above. In the first manuscript the aim was to prepare the reader for subsequent studies, and for that scientific productions about metacognitive monitoring and creativity in the last twelve years were analyzed. The second manuscript describes a correlational study, in which metacognitive knowledge and monitoring of university students were investigated during figural and verbal creativity tests. The metacognition was evaluated, in turn, through the application of the techniques developed by the researchers for this purpose, and from the description of the creative characteristics present in the manuals of crativity tests. From the data obtained in the second study, the third manuscript verified the occurrence of differences in the correlations between performance in the creativity tests and the estimates made in the techniques that measure the metacognition for different performance groups: 25% of students with minors and 25% of the students with higher scores in the tests of creativity.
Efeito do tamanho de partículas de Cu nas propriedades estruturais e eletrônicas e suas correlações com propriedades catalíticas na desidrogenação do etanol em Cu/SiO2
(Universidade Federal de São Carlos, 2019-03-08) Osmari, Taynara Andrea; Gallo, Jean Marcel Ribeiro; https://lattes.cnpq.br/3485408327490746; Bueno, José Maria Corrêa; https://lattes.cnpq.br/0157452280626031; https://lattes.cnpq.br/8862923856608795
Metal nanoparticles may exhibit distinct catalytic behavior when there are particle size variations at nanometric scale. Cu nanoparticles supported on SiO2 and CAB-O-SIL® were synthesized with different metal loadings by ammonium evaporation method in order to evaluate the particle size effect on the structural and electronic properties in the ethanol dehydrogenation to acetaldehyde reaction. Because this reaction is structure-sensitive, it has the activation of the O-H bond, which is the determining step, favored by a higher electronic density of the metallic center, characteristic of very small particles. Thus serving as a model reaction to evaluate the behavior of Cu0 sites. The synthesized catalysts were characterized by: i) evaluation of structural properties through XRD, TPR-H2, TPR-N2O, TEM, and EXAFS; ii) evaluation of electronic properties by FTIR-CO, XPS, and XANES; and iii) evaluation of kinetic parameters by DFT. The structural and electronic properties were correlated with the catalytic activity (TOFAcH) and apparent activation energy (Eap). The Cu/SiO2 catalysts presented smaller particles, higher dispersion, and lower reduction degrees than Cu/Cab. For both series, the presence of Cu-O scattering particles with Cu-Cu coordination number (NCu-Cu) below 8 was observed. Moreover, FTIR-CO and XANES results indicated increased Cu+ when NCu-Cu decreased with the Cu-Cu bond distance (RCu-Cu) of 1.842 (NCu-Cu = 4.4; NCu-O = 0.8) to 1.849 Å (NCu-Cu = 7.9; NCu-O = 0.3), which is less than RCu-O from the Cu2O bulk (RCu-O = 1.855 Å). Data of EXAFS and FTIR-CO suggest that Cu nanoparticles are formed by a core-shell structure. The contraction in RCu-O occurs with the presence of surface O interacting with Cu+ in the Cu core surface. Values of TOFAcH correlated with NCu-Cu suggest increased activity with increased particle size, which is contrary to expectations. However, the decrease of NCu-Cu results increased surface O and decreased RCu-O. The values of TOFAcH decreased and Eap increased with the decrease of RCu-O and NCu-Cu, demonstrating that the presence of surface O causes decreased electronic density of Cu0 sites. Data from DFT indicated higher ethanol heat of adsorption (ΔHEtOH) for clusters without surface O (13Cu: -51.92 kJ.mol-1) than clusters with O (13Cu4O: -26.97 kJ.mol-1), while the energy of the transition state for ethoxide formation remained constant. The results suggest that the relevant step for the activation of ethanol is the adsorption of ethanol, which is highly sensitive to the presence of O on the surface.
O alinhamento entre a contabilidade gerencial e a manufatura enxuta: estudo de casos multiplos em empresas brasileiras
(Universidade Federal de São Carlos, 2019-03-08) Fontenelle, Amanda Oliveira; Sagawa, Juliana Keiko; https://lattes.cnpq.br/6549481623896786; https://lattes.cnpq.br/6864885347234750
Lean thinking has proposed gains by reducing waste and failure and by intensifying continuous improvement. In this context, the Lean Accounting has emerged so that the accounting information could be aligned with the new type of production system. Some tools have been created, such as the Value Stream Costing, which enables to view the costs that are directly related and add value to the product. Based on a systematic literature review, it could be verified that there is a paucity of empirical research that presents prescriptive guidelines for applying accounting tools and practices aligned with lean manufacturing. The study herein aims at assessing the level of alignment between the management accounting systems in Brazilian companies and lean manufacturing practices. A systematic literature review was conducted in order to follow up on the theme's current state of art and to establish the constructs and dimensions for alignment. In addition, two descriptive case studies were conducted, in organizations that already have a certain maturity in the terms of application of lean manufacturing, in order to extract empirical characteristics that make it possible to measure the alignment between accounting and lean manufacturing. This research will contribute to the academic environment, filling the literature gap regarding the subject, and also to the organizational context, in which companies should know the available tools and pursue to align the entire accountingfinancial system in order to facilitate management and decision-making in business.
Restauração de imagens utilizando aprendizado de máquina
(Universidade Federal de São Carlos, 2019-03-08) Pires, Rafael Gonçalves; Levada, Alexandre Luis Magalhães; https://lattes.cnpq.br/3341441596395463; Papa, João Paulo; https://lattes.cnpq.br/9039182932747194; https://lattes.cnpq.br/8410467431339373
Image processing is an area that has received considerable attention as a result of the evo- lution of digital computing technology. One of the main techniques of image processing concerns its restoration, which consists in smoothing noise and detail enhancement, which are altered due to problems in the process of forming and transmitting the image. Based on the efficacy of sparse techniques and machine learning found in literature in the context of image restoration, we propose the union of these techniques as well as their evaluation in grayscale images. We also propose a study of energy-based networks such as Restricted Boltzmann Machines for noise suppression in binary images and the application of newer classifiers in this context, such as Optimum-Path Forest. Experiments using a public data- base corrupted by different degradations such as noise and/or blurring show the ineffective application of sparsity to different neural network architectures, the effectiveness of the Restricted Boltzmann Machines and the Optimum-Path Forest classifier.
Zeólitas ácidas aplicadas na esterificação catalítica
(Universidade Federal de São Carlos, 2019-03-08) Ribeiro, Maria Eduarda; Cardoso, Dilson; https://lattes.cnpq.br/2462847535959232; https://lattes.cnpq.br/1479000103307580
With respect the sugarcane sector expansion in Brazil, significant quantities of by-products have been generated, among them the fusel oil with potential for reuse due to the high volume produced and its rich isopentanol alcohol composition. An alternative of reuse is the transformation of this alcohol into ester, in this case, isopentyl acetate widely used in industries as flavors, solvents and others. In this context, the objective of the work was to apply commercial Si zeolites Si / Al = 15 and MFI with ratios (11.5, 15 and 25) in the protonated form as catalysts for the catalytic esterification of acetic acid the alcohols isopentanol and 1pentanol, in order to investigate the influence of the acidity, structure, and particle size of the catalysts in the catalytic activity. For this, the catalysts were characterized by: thermogravimetric analysis (ATG), X-ray diffractometry (DRX), nitrogen adsorption, scanning electron microscopy (MEV), desorption of ammonia at program temperature (DTP-NH3), spectroscopy energy dispersion (EDS) and X-ray fluorescence (FRX). By using the characterization techniques, it was found that commercially purchased materials corresponded to the one reported by the manufacturer. In addition, the characterization of samples with MFI structure showed that the Si / Al ratio has influence on shape, particle size, and acidity. In the catalytic tests, it was found that when comparing the MFI and USY structures with Si / Al = 15, it is not possible to identify which parameter had an influence on the catalytic activity, due to the number of variables. However, an improvement in the performance of the catalysts with the MFI structure with the increase of the Si / Al ratio was observed, this fact was attributed to the increase of the external surface.
Modificação de quitosana com ácido hialurônico e sua blenda com colágeno para aplicação biomédica
(Universidade Federal de São Carlos, 2019-03-08) Souza, Winicius; Komatsu, Daniel; https://lattes.cnpq.br/2620060426867863; Duek, Eliana Aparecida de Rezende; https://lattes.cnpq.br/4147198882685212; https://lattes.cnpq.br/5621428220533368
As in other areas of application, researchers in the field of biomaterials have been looking for materials from natural sources for the installation of implantable or curative devices, in this sense, a chitosan has been much studied. In spite of the properties that favor its application, its solubilization requires the use of acetic acid, whose result, in the structure of the scaffold, can impair an interaction as the host cells. In order to minimize this problem, the present work aimed to chemistry of chitosan with hyaluronic acid (HA) and to obtain its blend with collagen. Thus, the advantage is the following chitosan (Qm) chemistry to become useful in water and, in addition, provides a scaffold for the presence of AH, a glycosaminoglycan, a major component of the skin, to engage in tissue payment processes. The chitosan and AH changes were verified through the FTIR technique, where a chemical interaction with the reactive groups of the chitosan molecules was evidenced. The solubility test demonstrated great success with the water-soluble chitosan solution. The scaffolds, obtained by the lyophilization method, are the porous morphology and depend on the concentration of Qm, with concentrations of 9% and 17% of the highest porosity. The swelling test in phosphate-saline solution (PBS) showed that the scaffold with lower concentration of Qm (9%) was the one with the highest swelling rate. In turn, the thermogravimetry assay resulted in the presence of Qm decreased the thermal stability of the collagen. Finally, the DSC assay showed the miscibility of the collagen-Qm blend since it was subjected to a single vitreous transition temperature (Tg). These data allow us to verify the feasibility of using a new blend based on properties capable of forming a porous scaffold that can be used as a cutaneous dressing.