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Sorção de resíduos da indústria sucroenergética na obtenção de agronutrientes
(Universidade Federal de São Carlos, 2023-08-10) Antonio, Milena Maria; Faez, Roselena; https://lattes.cnpq.br/0654750186618555; https://orcid.org/0000-0003-1263-7837; https://lattes.cnpq.br/1139444069757211; https://orcid.org/0009-0004-1843-6977
Productive processes aim for efficiency, profitability, and environmental sustainability, necessitating waste management to prevent environmental impacts. In the agro-industrial sector, vinasse and the ashes from sugarcane bagasse burning (SCBA) are prominent by-products in the sugar and energy industry. The first is a substance with nutritional value for fields but exhibits specific properties that could harm the environment in the long term. The second is a solid material with valuable adsorptive characteristics for effluent treatments. This project aimed to apply the adsorption capacity of SCBA to adsorb nutrients N, P, and K from vinasse and improve the characteristics of these agro-industrial wastes for subsequent use in agriculture. The washed/dried CBCA was initially used in sorption experiments with NH4+, K+, and total P from simulated standard solutions of K2SO4 and (NH4)2HPO4, representing the vinasse concentrations. Analyzing the ashes before and after sorption experiments was essential to explain their performance. Different characterization techniques (FTIR, XRD, BET, SEM, TGA, and DSC) showed that CBCA is a micro-mesoporous, heterogeneous material with irregular, fibrous tubular, spherical, and prismatic particles containing SiO2 in the form of quartz and cristobalite. Besides, smaller masses of ashes with a contact time of 6 h were promising with standard simulated solutions for N, P, and K sorption evaluation. The same ideal systems were replicated for vinasse, requiring adjustment of the sorption time to 24 h. The results for both tests showed success in kinetics, especially for K+ and NH4+, and allowed the correction of vinasse pH due to the alkaline character of the ashes. However, the sorption behavior of nutrient P was distinct due to factors such as ion size and charge differences and interactions between P and silicon (from CBCA). The sorption kinetic models for K+ and NH4+ present diffusional interaction with the medium, not necessarily controlled only by adsorption on active sites exhibiting non-uniform characteristics. The non-linear Freundlich model also showed adsorption sites with different energy levels and a multilayer sorption process. Therefore, the sorption of nutrients in vinasse is feasible, adding value to waste materials and reducing environmental impact when used in agriculture.
Estudo da síntese in situ de nanopartículas e filmes finos de óxido de zinco dopado com alumínio por rota hidrotermal convencional e assistida por micro-ondas
(Universidade Federal de São Carlos, 2023-08-10) Serrão, Fernanda Thamiles de Jesus; Cordeiro, Marco Aurélio Liutheviciene; https://lattes.cnpq.br/4787678071396324; https://orcid.org/0000-0001-6287-3083; https://lattes.cnpq.br/1256204352058724; https://orcid.org/0000-0002-0303-4965
Zinc oxide (ZnO) is one of the most interesting materials due to its wide range of applications in various optoelectronic devices, such as light-emitting diodes, photodetectors, sensors, UV absorbers, solar cells, among others. However, ZnO's low electrical conductivity limits several of its applications, despite being a promising material for optoelectronic devices due to confinement effects. One way to overcome this problem is by doping, substituting Zn2+ ions with group III ions (B3+, Al3+, Ga3+, and In3+), which can promote electrons to the conduction band and improve the optical, thermal, magnetic, and electrical properties of ZnO. Among these dopants, Al3+ is the most commonly used due to its small ionic radius and low production cost. In this context, this study aims to synthesize and analyze the synthesis parameters of Al-doped ZnO nanoparticles (AZO) by using hydrothermal routes under conventional heating and assisted by microwave irradiation, in an aqueous medium. The materials and synthesis parameters will be characterized using X-ray diffraction (XRD), diffuse reflectance spectroscopy (DRS), Fourier-transform infrared spectroscopy (FTIR), Raman spectroscopy, transmission electron microscopy (TEM). For the syntheses deposited on glass substrates, optical microscopy (OM) and scanning electron microscopy (SEM) were performed.
O desenvolvimento da afetividade nas práticas pedagógicas na Educação Infantil à luz da Teoria Histórico-Cultural
(Universidade Federal de São Carlos, 2023-08-10) Tessarin, Maira Juliana; Mello, Maria Aparecida; https://lattes.cnpq.br/8338726751746542; https://lattes.cnpq.br/3686480544656683; https://orcid.org/0000-0002-9493-9937
This research was carried out within the Center for Studies, Research and Extension on the School of Vigotsky (NEEVY). Based on the Historical-Cultural Theory, especially on Vygotsky's texts, we find the concept of emotions as a fundamental element for the learning of human beings. This is because, upon entering school, children are affected by feelings and emotions that influence their perception of relationships and the world around them. Consequently, such social learning situations are challenging for them and for the teachers' actions. Thus, this investigation proposed to expand the analyzes of research already carried out regarding the development of affection with children, in Early Childhood Education. That said, our research question intended to answer the following question: what are the main contributions and foundations found in current research subsidized by the Historical-Cultural Theory, for the development of affectivity in children in Early Childhood Education? Therefore, our objective was to deepen the theoretical-practical discussion regarding the pedagogical work for the development of affectivity in children in Early Childhood Education, based on the research already carried out in the Cultural Historical Theory. As a methodology, we carried out a bibliographical and theoretical research, based on the method of historical-dialectical materialism and the genetic method of the Historical-Cultural Theory, based on the procedures and instruments proposed by Salvador. From the applied descriptors and filters, we found 2,719 national and international articles, of which 17 referred to our object of study. Data analysis occurred through three guidelines. In the first, we address the characteristics of research on affectivity in Brazil and in the world; in the second, we relate the main concepts of the Historical-Cultural Theory for the development of affectivity and in the third guideline, we discuss the subsidies that contribute to the pedagogical practices. As a result, we obtained research carried out in all continents that demonstrated the overwhelming fact of the need to modify attitudes towards more affective relationships. We affirm through the results that the dichotomization between reason and emotion, affection and cognition are convenient to the political and economic context of the current capitalist society, and we have in the dialectic conception an essential instrument to seek this overcoming. As subsidies for teaching practices, we suggest that pedagogical practices focused on analyzing the quality of children's expressive signals. Thus, encouraging participation, cooperation, sharing, communication appropriate to the activity, games and games are important ways for the development of affectivity. On the other hand, repressions, punishments and fanciful lies have negative effects, as they crystallize negative emotional experiences. Another excellent tool is the use of Art and the child's imagination in pedagogical practices, with its use in the plastic arts, poetry, music, dramatization and role-playing, since this connection unites emotion, interaction, creation and fantasy in the same activity, in addition to enabling emotional anticipation. Another important result of the research is the advancement of the Historical-Cultural Theory in research in Brazil and in the world, as its theoretical assumptions, method, methodology and concepts make it an important theoretical reference to explain the need for affectivity in social relations.
Fotoeletrodegradação e determinação voltamétrica de Propranolol
(Universidade Federal de São Carlos, 2023-08-10) Silva, Laís Pereira; Moraes, Fernando Cruz de; https://lattes.cnpq.br/8597473049054728; https://lattes.cnpq.br/3761586922669259
In this work, efforts were made to study the electrochemistry and application of semiconductor materials for the degradation of the drug propranolol. Semiconductors play a significant and indispensable role in advancing approaches to wastewater treatment. Within this context, this work developed photoanodes made from the semiconductor bismuth vanadate (BiVO4) deposited on the surface of conductive glass with fluorine-doped tin oxide (FTO). The photoanode was modified with copper oxide (CuO) to form a heterostructure and the system was photosensitized with electrodeposited silver phosphate (Ag3PO4). Four photoanode configurations were developed for comparison, namely: FTO/BiVO4; FTO/BiVO4/CuO; FTO/BiVO4/Ag3PO4 and BiVO4/CuO/Ag3PO4. The materials were morphologically characterized using the techniques of scanning electron microscopy, transmission electron microscopy and X-ray diffraction. The electronic characterization of the materials was carried out using the diffuse reflectance technique. The electrochemical characterizations of the photoanodes studied were carried out using linear sweep voltammetry and chronoamperometry measurements. Firstly, the voltammetric profiles of the photoanodes developed were evaluated and the photoanode with the highest current density, FTO/BiVO4/CuO/Ag3PO4. Subsequently, optimization studies of the photoanode were carried out, such as silver phosphate electrodeposition time and potential, LED power, support electrolyte, pH, among others, in order to verify the best experimental condition, since these studies can influence the intensity of the photocurrent. The processes of photodegradation, electrodegradation and photoelectrodegradation were evaluated to verify the influence of UVc radiation and the application of + 1.4 V during 4 hours of drug degradation. The degradation of the propranolol molecule was monitored using UV-vis spectroscopy. The percentage degradation of propranolol using each process and the FTO/BiVO4/CuO/Ag3PO4 photoanode was calculated, giving degradation percentages of 35.0, 25.0 and 68.5% for photocatalysis, electrocatalysis and photoelectrocatalysis, respectively. Propranolol concentration decay curves using the photoelectrodegradation system and the FTO/BiVO4/CuO/Ag3PO4 photoanode were obtained and used to calculate the kinetic constant, where k = 5.52 × 10˗3 min˗1 was obtained. For comparison purposes, propranolol degradation experiments were carried out using the photoanodes FTO/BiVO4; FTO/BiVO4/Ag3PO4; FTO/BiVO4/CuO and FTO/BiVO4/CuO/Ag3PO4, where the degradation rate was 25,5%; 13,7%, 33,5% and 68.5%, respectively. Finally, the Total Organic Carbon (TOC) analysis was carried out using the different photoanodes FTO/BiVO4; FTO/BiVO4/CuO; FTO/BiVO4/Ag3PO4; and FTO/BiVO4/CuO/Ag3PO4, where values of 15.6%, 20.0%, 23.2% and 25.7% were obtained, respectively. Based on these results, the energy involved in the degradation system was estimated at 10,1 kWh kg˗1. As the second part of the work, a sensor was developed using carbon black (CB) and tungsten trioxide (WO3) materials, where the voltammetric profile of the analyte was first evaluated against the different electrodes (GCE; CB/GCE and WO3-CB/GCE). The compositions and pH values for the support electrolyte were studied in order to obtain the best analytical signal (voltammetric response) for the determination of the antihypertensive. The parameters that influence the differential pulse voltammetry technique, such as amplitude, modulation time and speed, were evaluated and optimized. The values were selected (a = 30 mV, t = 15 mV and v = 20 mV s-1) considering the repeatability, stability and magnitude of the analytical signal for WO3-CB/GCE in the determination of PROP. The analytical response was linear over the concentration range 1.00 × 10˗7 to 2.53 × 10˗6 mol L˗1, and followed the following linear regression equation: Ip (μA) = 1.88 × 10˗2 + 0.122 [PROP] (μmol L˗1); r2 = 0.998 with a detection limit of 4.04 × 10˗8 mol L˗1 calculated as three times the standard deviation of the blank (n = 10), divided by the slope of the analytical curve (analytical sensitivity). The accuracy of the voltammetric procedure was verified through intra-day (n = 10) and inter-day (n = 3) repeatability studies for two different concentrations of propranolol. As a result, intra-day repeatability values of 4.52 and 1.59 were obtained for the two concentrations of 6.95 × 10˗7 and 2.15 × 10˗6, respectively. For inter-day repeatability, values of 5.39 and 1.84 were obtained for 6.95 × 10˗7 and 2.15 × 10˗6, respectively.
Merge trees decoradas e TDA
(Universidade Federal de São Carlos, 2023-08-10) Falsarella, Guilherme de Carvalho; Vendrúscolo, Daniel; https://lattes.cnpq.br/8602232587914830; https://lattes.cnpq.br/1490485501695324
In this document, first we will introduce Persistance Homology and Category Theory basic concepts. Afterwards, we will develop the Merge Tree Theory which will be useful to keep track of connected components evolution of a given dataset. Finally, we expand this Merge Tree Theory to be able to study the Decorated Merge Trees, where this decoration correspond to higher degree homology.
Temos a terra, e agora, somos livres? : um estudo sobre o processo organizativo no Projeto de Assentamento Nova Tangará – Uberlândia, MG
(Universidade Federal de São Carlos, 2023-08-10) Vasconcellos, Inaê Soares de; Scopinho, Rosemeire Aparecida; https://lattes.cnpq.br/4770451465556845; https://lattes.cnpq.br/2915325152351594
The process by which people in the Nova Tangará rural settlement build (and deal with) their conditions of social and political organization and their socio-productive inclusion is the main theme of the work. With theoretical and historical support relating to the issue of land and ruralities in Brazil coming from the works of Ignácio Rangel, José de Souza Martins, Klaas Woortmann, José Graziano da Silva, Sérgio Sauer, Leonilde Medeiros, Bernardo Mançano Fernandes, and in epistemological consonance with Pierre Bourdieu in his notions of strategy, habitus and class, the following research question was elaborated: with land ownership, are subjects now autonomous? What is the content of this autonomy? The hypothesis is that most members of that settlement seek to maintain the highest possible levels of autonomy from the perspective of ownership. The idea of a settlement community, in this sense, would be a subjective inconvenience for most settlers; It would be better to have social recognition as a family farmer. A theoretical deepening was carried out, contained in the first chapter, identifying that land income, discussed by Ignágio Rangel, José de Souza Martins and José Graziano da Silva, is a fundamental category to understand the processes of individualization of subjects in their lots, difficulties in community organization and social and productive precariousness observed in the settlement. Regarding methodological aspects, the procedures were interviews, application of questionnaires and review of bibliography on the settlement in question. In the second chapter, the characteristics of the Movement that organized the occupation and the camp between 1999 and 2003 are discussed, as well as the relationships between that group, after the settlement was established, from 2004, and the settlers , observing the tension between property and autonomy inherent to this relationship. The third chapter seeks to identify and analytically elaborate the fundamental characteristics of autonomy/freedom and its relationship with the ownership of the lot for the settlers. In the fourth and final chapter, the most important discoveries of the work and the perspectives of community building are presented, as well as the challenges of this process.
Avaliando os efeitos de uma audiência punitiva versus de uma audiência não punitiva sobre a acurácia do relato verbal de crianças
(Universidade Federal de São Carlos, 2023-08-10) Silva, Joice Cristina Cintra; Cortez, Mariéle Diniz; https://lattes.cnpq.br/7927746584626515
The present study evaluated the effects of two different audience functions (punitive and non-punitive), whose discriminative functions were established experimentally, on the accuracy of children's verbal reports. Six typically developing children aged between eight and 10 years participated; however, the data from only three participants, who met the inclusion criteria, were considered for the analysis. "Doing" consisted of shooting at a target in a computerized game and "saying" consisted of reporting their successes and errors by clicking on one of two colored squares displayed on the screen after each trial (green for reporting successes and red for reporting errors). At the end of each session, the participant reported the number of points obtained during the task for the current audience (punitive or non-punitive). The experimental conditions were: 1) Baseline, which assessed the correspondence of the report in the absence of the different audiences and without programmed differential consequences ; 2) Establishment of the punitive and non-punitive discriminative functions of the audiences, which experimentally established the discriminative functions of the audiences (punitive and non-punitive) and 3) Test of the discriminative functions of the audiences, which assessed the correspondence of the report as a function of the different audiences, without programmed consequences. An adapted alternating treatment design was used to compare the effects of the two different audiences and a multiple baseline design across participants to compare the effect of introducing the different audiences in relation to the control condition. The data were analyzed in terms of the percentage of corresponding reports of errors during the computer game and the correspondence of the final report about the total points obtained for the different audiences at the end of each session. The results showed that two of the three participants showed an increase in the levels of correspondence of the reports made during the computerized game when the audiences were introduced. However, the levels of correspondence were not differentially influenced by the different functions of the audiences in the study. Parameters of the procedure for establishing the discriminative functions of the audiences were discussed as a factor to be better investigated in future studies.
Campos de vetores suaves por partes: preservação de medida, pressão topológica e dinâmica simbólica
(Universidade Federal de São Carlos, 2023-08-10) Florentino, Marco Aurélio do Carmo; Cassiano, Jeferson; https://lattes.cnpq.br/1901026809787581; Carvalho, Tiago de; https://lattes.cnpq.br/3779225124392648; https://orcid.org/0000-0003-3927-938X; https://lattes.cnpq.br/8827594656964359; https://orcid.org/0009-0001-5538-3075
The study of piecewise smooth vector fields (PSVFs) has been consolidated in recent years not only because of the beauty of the theoretical results, but also because of the proximity of this area to applied sciences such as mechanics, engineering, electronics and biology, in addition to social sciences and economical. The main difference between PSVFs and smooth vector fields is the fact that there may not be unique the trajectory passing through each point a PSVF. With the existence of chaos, we can look for ways to calculate the topological entropy, since entropy estimates how chaotic the environment is system. In this work we follow this line of investigation and obtain a set of piecewise smooth vector field trajectories where the application of time one is well defined. In this way, we obtain a conjugacy between the itinerary of a trajectory contained in this set and sequences over a finite set of symbols. Thus, we study some aspects of thermodynamic formalism, more specifically topological pressure and, consequently, topological entropy for piecewise smooth vector fields, using topological conjugacy with one-sided shifts and the Ruelle-Perron-Frobenius Operator. Some relations between entropy, Hausdorff dimension and Minkowski dimension are also presented. In this sense, when the pressure is zero, we can use the Markov chain theory together with the Ruelle-Perron-Frobenius operator to calculate the relaxation time and estimate the mixing time for PSVFs. Finally, we introduce the concept of sliding-escaping connection for piecewise smooth vector fields and establish conditions in order to obtain a set of trajectories that preserves measure even in the case where sliding motion is allowed. As consequence, classical results from the ergodic theory of dynamical systems can be adapted for the context of piecewise smooth vector fields with a sliding-escaping connection, namely, the Poincare’s Recurrence Theorem and the Birkhoff’s Ergodic's Theorem.
Aprendizagem da docência de professoras iniciantes em um programa de mentoria: processos reflexivos e autonomia
(Universidade Federal de São Carlos, 2023-08-10) Machado, Micheli Fernanda; Anunciato, Rosa Maria Moraes; https://lattes.cnpq.br/3064136997342775; https://orcid.org/0000-0003-1478-411X; https://lattes.cnpq.br/6043276985613024; https://orcid.org/0000-0003-3276-7225
This doctoral thesis aims to analyze and comprehend the reflective processes and autonomy in the teaching learning of early-career teachers participating in the Hybrid Mentoring Program (PHM). The PHM was a research intervention that had the financial support of FAPESP and was developed from a constructive-collaborative perspective, combining both in-person and distance activities within a virtual learning environment (VLE) on the Moodle platform, through the UFSCar Professors Portal. In PHM, mentors (experienced teachers with over 10 years of experience) helped beginning teachers (with up to five years of experience) in their professional development. The methodology employed is qualitative and relies on descriptive and interpretative analysis of the narratives from novice teachers and mentors, both individual productions and the record of interactions in the PHM that constituted the data source. The results reveal that the Program has made significant contributions to the professional development of the participants. It was verified that the partnership established between novice teachers and mentors provided the teachers with help in situations of coping with the difficulties present in the school context and, by being inserted in reflective processes, they were able to rethink their own practices in a collaborative way, a fundamental factor in becoming an autonomous professional. The importance of programs like this was perceived as a subsidy for the elaboration of public policies that can contribute to the professional development of teachers throughout their careers. The narratives as a process of investigation and reflection proved to be important means to understand the contributions of the Hybrid Mentoring Program in building the autonomy of teachers at the beginning of their careers, the reflection on the practices of those involved in a context of social transformations and in the education system itself, as well as contributing to research in the field of teacher education.