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Direito à água: contribuições para o acesso mais justo, equitativo e democrático à água
(Universidade Federal de São Carlos, 2025-03-31) Moraes, Tatiana Vieira de; Oliveira, Celso Maran de; https://lattes.cnpq.br/9911833172043700; https://orcid.org/0000-0002-6442-3614; https://lattes.cnpq.br/3999527499047171; https://orcid.org/0000-0002-1665-6421
Water in quantity and quality is an essential human right, but a large portion of the population still does not have access to this right. SDG 6 sets the goal of universal and equitable access to water for all people by 2030 and, based on the hypothesis that the current Brazilian water management system does not sufficiently guarantee access to the right to water in an equitable and fair manner, this study aims to identify, based on case studies of water conflicts, various possibilities and potential actions, measures or principles with a view to contributing to fairer, more equitable and democratic access to the right to water. To this end, methodological pluralism was adopted, with each chapter addressing a set of specific methods and procedures. The study is presented in three parts: the first, more theoretical, proposes a literature review. At this point, the right to access water as an essential human right is discussed, pointing out the possibility of considering water as a fundamental right in Brazil, even without express constitutional provision. It also analyzes the Brazilian National Water Resources Policy and criticizes the conventional model of water resources management adopted in Brazil, especially its limitations in terms of participation and equity. This is followed by a discussion of effective water governance, highlighting the importance of a governance system that strengthens the participation of society. This part of the study concludes with theoretical clarifications on the concept of water equity, presenting definitions and basic elements, as well as differentiating equity from water justice. The second part examines case studies of water problems/conflicts. Adopting a narrow geographical approach, a survey was carried out of cases of international and national water conflicts in the literature; in the state of São Paulo through Civil Inquiries by the Public Prosecutor’s Office of São Paulo (MPSP); and a local case in the municipality of São Carlos/SP. The results of this part of the study were the mapping of water conflicts based on the cases examined and the potential of the measures and solutions suggested and/or applied to resolve or mitigate the conflicts. The third part of the study is propositional, presenting contributions to more equitable and democratic access to the right to water and interconnecting the first two parts. The analyses of the previous parts of the study demonstrate the existence of various inequalities in access to water and the inadequacy of the conventional water management system to sufficiently guarantee fair, democratic and equitable access to the right to water. As a result, contributory proposals were generated aimed at advancing the transition from the current water management format to a more effective system of ‘good water governance’ that promotes democratic, equitable and fair access to the right to water.
Modelagem multiescala e validação experimental da dinâmica interfacial em sistemas de eletrólise da água: explorando fenômenos locais inerentes das reações eletroquímicas
(Universidade Federal de São Carlos, 2025-03-31) Leite, Gabriel Wosiak; Souza, Ernesto Chaves Pereira de; https://lattes.cnpq.br/1505400360366643; https://orcid.org/0000-0003-1058-302X; https://lattes.cnpq.br/8033550667466489; https://orcid.org/0000-0002-1705-9100
This thesis addresses the efficiency challenges in hydrogen production via water electrolysis, focusing on the coupled effects of gas bubble evolution and interfacial pH variations during alkaline electrolysis. Multiscale computational models were developed, combining the Finite Element Method (FEM) and Computational Fluid Dynamics (CFD) to simulate bubble dynamics and interfacial pH distribution, with experimental validation using filming techniques and chronopotentiometric analysis to explore energy consumption during electrolysis. The results showed that pulsed-current operation can mitigate local pH variations; however, maintaining stable pH conditions under high current densities remains a challenge. Additionally, an asymmetric electrolysis cell configuration was proposed and validated, demonstrating a reduction in local pH gradients and up to a 17% improvement in electrolysis efficiency. This work opens new perspectives for developing more efficient electrolyzers, contributing to sustainable and economically viable hydrogen production.
Como a alfabetização científica se desenvolve no contexto da educação básica: um olhar sobre a prática docente
(Universidade Federal de São Carlos, 2025-03-31) Stranghetti, Natalia; Marques, Clelia Mara de Paula ; https://lattes.cnpq.br/0451284088402660; Venâncio, Tiago; https://lattes.cnpq.br/4438399441102990; https://lattes.cnpq.br/2628000000410865
This study aimed to analyze the presence and development of Scientific Literacy (SC) in Basic Education, highlighting its relevance as an essential tool for understanding and applying scientific knowledge in everyday life and in the modern world. To this end, Chemistry classes were monitored in two state schools, seeking to identify the presence of SC in basic education. In addition, the teachers of these classes were interviewed, allowing a qualitative analysis based on the principles of Bardin's Content Analysis. Initially, SC indicators observed during classes were collected, while categories were created for essential aspects that did not appear, but are fundamental for the development of SC in education. In order to deepen the investigation, interviews were conducted with other teachers from the state network to understand their perceptions about SC. The research also included the analysis of legislation and documents guiding education in Brazil, such as the National Common Curricular Base (BNCC) and the Law of Guidelines and Bases of National Education, in order to verify how SC is addressed in curricula and pedagogical guidelines. The results indicated that CA is present in Basic Education, but there is a vast potential that has not yet been explored, since several essential parameters were not identified in the observed teaching practice. The study suggests that CA could be significantly more stimulated if there were greater awareness and guidance among education professionals about its importance. In addition to the lack of specific knowledge, it was found that the limited time allocated to the study of teaching tools and methods compromises the development of pedagogical practices that facilitate the learning and understanding of scientific content.
Feijão guandu para uso alimentar: composição química, funcionalidade e aspectos nutricionais
(Universidade Federal de São Carlos, 2025-03-31) Tozo, Marcelo Larsen de Lima; Rita de Araujo Nogueira, Ana; https://lattes.cnpq.br/7034773971317045; https://orcid.org/0000-0003-3648-2956; https://lattes.cnpq.br/6205481423806854; https://orcid.org/0000-0002-6672-5851
This dissertation aims to develop and apply analytical procedures to evaluate the total levels, bioaccessibility, and bioavailability of essential elements and total proteins in two pigeon pea (Cajanus cajan (L.) Millsp) varieties previously selected for human consumption. Raw and cooked samples were evaluated at different stages of maturation, as well as commercial varieties of common beans (carioca and black). Bioaccessibility and bioavailability were obtained after in vitro gastrointestinal digestion simulations and bioassays with Caco-2 cells. For proteins, the total fraction and the bioaccessible fraction were quantified by combustion (Dumas), and free amino acids by high-performance liquid chromatography (HPLC). The macro and micronutrients evaluated, Ca, Mg, P, Cu, Fe, and Zn, were determined by inductively coupled plasma optical emission spectrometry and mass spectrometry (ICP OES and ICP-MS), after microwave-assisted decomposition using diluted acid (7.0 mol L-1), both for total contents and for bioaccessible and bioavailable fractions. The bioaccessibility of elements varied from 0.8 to 19% for Ca and from 48 to 67% for Cu. Bioaccessibility of Ca, Fe, Mg, and Zn decreased with bean maturation. Finally, an in vitro intestinal simulation with Caco-2 cells, aimed at estimating nutrient bioavailability, faced issues with the integrity of the cell monolayer, making it impossible to estimate bioavailability values. However, the results obtained suggest the direction to be followed for improving this experiment and obtaining reliable results. Regarding crude protein content, pigeon pea samples were close to 20%. For amino acids, amounts ≥ 1% of glutamic acid, aspartic acid, and leucine were found. For the mature grain, lysine and phenylalanine were present in amounts ≥ 1%, compared to the green grain. However, in the mature grain, the amounts of glycine, histidine, threonine, alanine, and tyrosine were low (≤ 0.4%), and no methionine, cystine, or taurine were detected in either grain. The protein bioaccessibility varied between 16.4% and 19.4%. There was an increase in the total protein content with the maturation of the beans, while the bioaccessible percentage remained unchanged. For the recommended daily intake (RDI), the consumption of 100 g of cooked food suggests that the pigeon pea may be an alternative source of nutrients, highlighting Mg and P, although its contribution is lower compared to the commercial varieties of carioca and black beans. Additionally, all the beans studied show potential for protein supplementation, ranging from 32.8 – 38.8% of the RDI, reinforcing the importance of these legumes and others in human nutrition.This study is significant from a nutritional perspective, providing unprecedented data on the nutritional aspects of two varieties of pigeon peas and the bioaccessibility of essential elements, indicating their use as a consumption alternative.
Fusão em leito de pó a laser de aço ferramenta A2: efeito de parâmetros de processo, tratamentos térmicos e adição de Cr₃C₂
(Universidade Federal de São Carlos, 2025-03-31) Bianchini, Bruno; Gargarella, Piter; https://lattes.cnpq.br/4641435644243916; https://orcid.org/0000-0003-4445-5819; https://lattes.cnpq.br/8443988120967281; https://orcid.org/0000-0002-5542-587X
Tool steels have strict requirements for composition, processing and mechanical properties, and are utilized in fabrication of molds or tools employed in the processing of other materials. In many cases, they are expensive and of difficult machinability, which opens up the possibility for alternative processing routes such as additive manufacturing (AM) by Laser Powder Bed Fusion (L-PBF), which allows fabrication of parts with complex sections, such as internal cooling channels, without additional processing cost and with minimal need for post-processing, due to its great dimensional accuracy. However, the severe conditions to which the L-PBF process submits materials induce the formation of a highly refined microstructure, and possibly defects. This work studies the possibility of manufacturing AISI A2 tool steel by L-PBF, considering the effect of process parameters and post-processing in its microstructure and properties, and the modification of this material for defect mitigation. Results showed that, despite it being possible to determine a processing window for minimal porosity, the material composition and the severe processing conditions cause the formation of cracks, mostly during solidification. The as-built microstructure is, similarly to other tool steels manufactured by L-PBF, composed of martensite cells surrounded by retained austenite, while the formation of primary carbides is suppressed. After heat treatment, the formation of secondary carbides was found to be also in low quantity, showing that temperings without prior austenitization would need higher temperatures or longer times to cause significant effects on the microstructure and mechanical properties. Finally, it was discovered that the addition of Cr3C2 chromium carbide by mechanical mixture, at a fraction of 5%, was capable of mitigating defect formation by altering the alloy composition, when manufactured by L-PBF.