Navegando por Data de Publicação, começando com "2022-09-21"

Filtrar resultados por ano ou mês

Agora exibindo 1 - 9 de 9

Durabilidade a longo prazo de concretos produzidos com agregados de escória de aciaria BSSF
(Universidade Federal de São Carlos, 2022-09-21) Cartaxo, Fábio de Moraes; Ferreira, Fernanda Giannotti da Silva; https://lattes.cnpq.br/0329487394818763; https://lattes.cnpq.br/3166536985750587
The steel slag is a steel co-product with an expansive behavior, which, for incorporation into civil construction products, needs to go through stabilization processes. The process called BSSF (Baosteel's Slag Short Flow) is a technological novelty in Brazil in which large amounts of material can be cooled and stabilized in less time compared to conventional treatment. Thus, this work aims to identify the technical feasibility of concrete produced with the incorporation of steel slag aggregates stabilized by the BSSF process. The concrete mixes were developed for environmental aggressiveness class II, with a minimum strength of 25 MPa at 28 days. As materials, CP V-ARI, granitic gravel, quartz sand, BSSF steel slag and superplasticizer additive were used. The mechanical properties of axial compressive strength (ages 7, 28, 365 days) and static modulus of elasticity (ages 28, 91 and 365 days) were determined. Regarding the properties related to durability, volumetric stability over 365 days of observation, carbonation depth (age 28 days) and penetration of chloride ions (ages 28, 91 and 365 days) were evaluated. Finally, the potential for contamination by solubilization and leaching of the produced concrete was evaluated. In general, in relation to the reference mix, concretes with BSSF steel slag aggregates presented superior mechanical performance, similar durability characteristics, and low contamination potential (within the limits of NBR 10004). The EA40 and EA60 traits stand out, with the best mechanical results, without losses in terms of durability. However, the concretes produced are not suitable for applications in environments subject to chloride ion attacks, such as coastal regions.
Análise comparativa dos custos operacionais e de implementação de sistemas de abastecimento de água considerando reservatório elevado e booster
(Universidade Federal de São Carlos, 2022-09-21) Cremasco, João Pedro; Kellner, Erich; https://lattes.cnpq.br/6855091004957784; https://lattes.cnpq.br/8907241162098898
Water supply systems in their reservoir and distribution stage can present different solutions, such as elevated reservoirs or booster pressurization systems. The elevated reservoirs are composed of an upper and lower chamber, with the water being pumped from the lower to the upper chamber, from which it is distributed by gravity. The pressurization systems are composed of a supported reservoir and a variable speed pump, which works uninterruptedly unlike the elevated reservoir configuration. The present work sought, by means of a hydraulic modeling in EPANET, to make a comparison of operational costs and implantation costs of these two reservoir and distribution configurations, having as study object the lot "Jardim do Bosque" located in the city of São Carlos (SP). The variables analyzed were the volume stored in each one of the reservoir chambers, as well as the pumped flow rate in each one of the situations. The results obtained indicate that the elevated reservoir has lower energy operational costs and the pressurizing system has lower reservoir implementation costs. For the case studied, the best alternative is the elevated reservoir, due to the considerations made about the beneficiaries.
Revisão sobre o uso de adições minerais em concretos sustentáveis
(Universidade Federal de São Carlos, 2022-09-21) Teodoro, Laura Helena; Ferreira, Fernanda Giannotti da Silva; https://lattes.cnpq.br/0329487394818763; https://lattes.cnpq.br/1025927721819994
The civil engineering sector, despite being necessary for human comfort and development, is one of the biggest contributors to the perish of these resources. Therefore, it is important to implement techniques to promote better environmental conditions and achieve sustainable construction. Within the theme of sustainability in civil construction, recycling and reuse of materials as substitutes for cement or aggregates plays a major role in reducing CO2 emissions and, consequently, in making concrete more sustainable. Therefore, the present work, of bibliographic scope, seeks to evaluate the current techniques for the reuse of materials, using them as raw material for another product. In civil construction and other areas, there is a lot of waste that is wasted and can be reused, being the solution to avoid the extraction of natural products. Some additional cementitious materials, incorporated replacement levels, as well as the effect of these additions on the compressive strength of concrete were evaluated, highlighting the importance of recycling and reuse of waste in civil construction. For this evaluation, a database was created with compressive strength results available in the literature. These data were used in comparative analyzes that took as reference the results corresponding to the additions of fly ash, rice husk ash, glass powder and blast furnace slag. It was not possible to reach a definitive conclusion because there was a great variation in the results of compressive strength of concrete for all materials, only the glass powder that did not show an increase in strength at 7 and 28 days for the analyzed data, fly ash showed increases up to 20% replacement, rice husk ash showed improvement up to 25% replacement, and blast furnace slag had the best results for 100% replacement.
Rotina escolar em casa dos filhos com Trissomia 21 durante o isolamento social na visão das Mães/Pai
(Universidade Federal de São Carlos, 2022-09-21) Freitas, Milena Lucania; Galvani, Márcia Duarte; https://lattes.cnpq.br/6866106661255961; https://orcid.org/0000-0003-1092-746X; https://lattes.cnpq.br/5060617029857118; https://orcid.org/0000-0002-2781-4296
The Coronavirus pandemic caused the suspension of face-to-face classes, and schools and families had to reorganize to continue school activities remotely. The present study had the general objective of verifying the school routine of children and adolescents with Trisomy 21-T21, from Kindergarten and Elementary Education in public and private schools, based on parents' reports. The specific objectives were: (a) to identify possible changes in school routine during social isolation, in the opinions of parents of children with T21; (b) to verify the support demands of the parents and (c) to analyze how was the communication between parents and school in this period. For this, after complying with ethical procedures, the research was disseminated and participants were recruited through social networks. As the participants were indicated, they were contacted to schedule the interviews online. Study participants were 19 mothers and one father with children diagnosed with T21. This is a descriptive study with a qualitative approach, in which data collection was carried out through interviews with parents. The instrument used was a semi-structured interview script with open and closed questions. The collected data were transcribed and analyzed through the elaboration of categories. The results showed that the mothers were able to participate more actively in the schooling process of their children with T21, assuming roles of learning mediators, and the only participating father, due to working hours, was unable to be present and indicated the need to greater participation. The results also showed that this greater responsibility given to them in the pandemic context generated emotional conflicts in the mothers, such as anxiety and guilt, a reason caused by the lack of support from professionals at the school institution in establishing a relationship with the family with necessary and targeted pedagogical guidance. . On the other hand, it was reported by the participants that communication with the school improved during this period. The data highlight the importance of support networks with special education teachers to collaborate with the schooling of students with T21 and bring relevant subsidies for public policies, programs and post-pandemic actions.
Método de obtenção das magnetizações de blocos magnéticos de NdFeB a partir de perfís de curvas de integral de campo magnético
(Universidade Federal de São Carlos, 2022-09-21) Santo, Gustavo Correia Espirito; Soares, Vitor Pereira; Zabotto, Fabio Luis; https://lattes.cnpq.br/8828635263888498; https://lattes.cnpq.br/7494048754218672
Synchrotron light is a type of electromagnetic radiation emitted when relativistic charged particles are subjected to an acceleration perpendicular to their velocity, such as the acceleration created by the force of a magnetic field. When passing through a magnetic field, the particle undergoes a deflection in its trajectory, causing synchrotron radiation to be emitted in the tangent direction of its path. It is extremely bright and spans a wide spectrum, allowing different types of analysis to be performed with the different radiations that compose it. The main equipment responsible for producing this type of radiation are called Insertion Devices (ID). Consisting of a set of dipoles with alternating polarity, these devices cause oscillations in the path of electrons, causing them to emit radiation. An extremely important figure of merit for IDs is the field integral, which effectively represent the effects caused by a magnetic field on charged particles. In this way, the field integrals provide the angular and positional deviations of the output electron path with respect to the input path in the insertion devices. Magnetic simulations are used in order to describe and predict such parameters. However, to carry out the simulations, it is necessary to know precisely the geometric and magnetic parameters involved in such a process. Thus, the present work intends to present a method for determining the magnetization components of magnetic blocks used in insertion devices, from field integral curve profiles, allowing to reliably predict the various magnetic parameters that involve accelerator physics, through the magnetic simulations. This method was tested and validated, managing to satisfactorily describe the effects for a set of periodically arranged blocks, called subcassette, simulating the magnetic field and field integral curves, obtaining differences < 50 G.cm.
Avaliação das propriedades física e mecânica de cimentos com a incorporação do pó de vidro
(Universidade Federal de São Carlos, 2022-09-21) Vasconcelos, Arthur de Sousa Lima; Ferreira, Fernanda Giannotti da Silva; https://lattes.cnpq.br/0329487394818763; https://lattes.cnpq.br/3144392961222299
The use of glass powder in the cement composition as supplementary cementitious material (SCM) is an excellent alternative to mitigate the amount of waste generated by the glass industry itself, as well as reduce the amount used of clinker, the main raw material of Portland cement (PC). Moreover, the incorporation of glass can bring benefits in the properties of cementitious matrices both in the fresh and hardened states. To analyze the physical and mechanical properties of the incorporation of glass powder in the cement composition and meet the requirements of NBR 16697, the setting times, normal consistency of the paste and compressive strength of Portland cement matrices with incorporation of glass powder at 0%, 5%, 15% and 25% were determined. In the compressive strength test, 50x100mm cylindrical specimens were broken at ages of 3, 7 and 28 days for each cement. The materials used in this study are: CP V-ARI, normal sand and the glass powder from amber colored bottles with particle size passing the #200 mesh sieve. The increase in the incorporation of ground glass in the analyzed cements provided a higher fineness modulus and initial setting time directly impacting the workability and decrease in the initial mechanical strength due to the pozzolanicity of the glass. At 28 days, a reduction of 8.83%, 19.45%, and 26.72% was observed for cements with contents of 5%, 15% and 25% of glass powder, respectively, in relation to the reference with compressive strength of 54.12 MPa. Furthermore, the statistical analysis of the mechanical strength indicated that there is no statistical difference between the ages analyzed for the reference mixture and with 5% glass powder. Among the tests performed, the minimum requirements were met for all cements studied except for the compressive strength at 7 days of age for CP75PV25, which obtained the value of 32.13 MPa. Thus, the mix that relates the highest incorporation of glass powder in the composition of the cement and meets the minimum requirements established by NBR 16697 for the tests developed, is the cement with the incorporation of 15% ground glass as mineral addition.
Setor de serviços: uma análise de insumo-produto inter-regional para São Paulo e o restante do Brasil
(Universidade Federal de São Carlos, 2022-09-21) Paula, Leonardo Gabriel Xavier da Cunha de; Oliveira, Maria Aparecida Silva; https://lattes.cnpq.br/3455553543736709; https://orcid.org/0000-0001-7729-4068
This study aimed to show which are the main intersectoral relations of purchase and sale of the services sector in the regional economy of São Paulo and in the rest of the country, setting a target to the regional development policies. The main factors that justify the growth of the sector to the world and national economy were highlighted, in addition to the evolution determinants of its productivity. Furthermore, the study showed, by the theoretical basis of Regional Economy, the reasons for the service sector’s concentration in São Paulo and the importance of isolating the region from the rest of the country. Thus, an inter-regional input-output matrix of 2011 was used, aggregated into two regions (São Paulo and Rest of Brazil) and 31 sectors. Production multipliers and Rasmussen-Hirschman linkage indices were calculated for the sectors of both regions. The hypothetical extraction method was also applied to the segments of the sector. The results showed that the service sector in the state of São Paulo has a greater capacity to production stimulation, in addition to having more relevant segments for economic linkages than the sector in the Rest of Brazil. Moreover, it was shown that the main impacted by the hypothetical extraction of the service sector segments were the segments of the sector itself, especially Trade and Transport. Thus, it can be concluded that, within the service sector, the knowledge-intensive and technological innovation-inducing segments in the state of São Paulo are the main key sectors for the regional and interregional economy.
Aprendizagens de professores da educação infantil de conceitos geométricos tendo o origami como material com vistas ao desenvolvimento de práticas de ensino
(Universidade Federal de São Carlos, 2022-09-21) Presse, Priscila Marçal; Sousa, Maria do Carmo de; https://lattes.cnpq.br/6637658562543505; https://lattes.cnpq.br/3841537190882197
This dissertation aimed to analyze the learning of early childhood education teachers about geometric concepts using origami as a playful and didactic material with a view to the development of teaching practices. This research was driven by the following question: what are the learnings of early childhood education teachers about geometric concepts when they use origami in the context of an online course? To answer this question, substantiate and support this dissertation, the Historical-Cultural Theory was used, in which Vygotsky seeks to show that human knowledge derives from social relations with the use of language and signs. The methodology was qualitative and the data were obtained from the analysis of episodes that are characterized from the subject's speech, gestures and action. The methodology is qualitative. Origami was used as didactic material in order to enable learning about the teaching of geometric concepts in the context of early childhood education, based on experiences that took place among teachers, in a context of continuing education. The empirical material was compiled from a bibliographic survey and experiences that occurred during the development of an online course that was offered to Early Childhood Education teachers, from August to October 2021, together with the Municipal Secretary of Education in a municipality located in the interior of the state of São Paulo. Google Meet platform was used to teach classes and Google Classroom to send and receive problem situations involving origami, since, at that moment, we were in a pandemic context. The analyzes of the learning were carried out based on the following categories: 1) Learning that took place during the teachers' interactions when performing the folds: difficulties and facilities; 2) Learning that considers the recognition of geometric figures in the composition and decomposition of origami and 3) Learning that occurred during the recognition of geometric concepts in the composition and decomposition of origami. Based on these categories, it was possible to observe that teachers enrolled in this course because they considered the topic presented to be interesting and because they wanted to learn how to make origami, as well as discovering different ways to use it in the classroom. In other words, they wanted to learn how to use origami as a playful and didactic material during their classes. At first, we emphasize that, during the presentation of possible geometric concepts, among them the composition and decomposition of geometric figures that can be approached with origami, some teachers were reluctant to participate in the discussions in the virtual class because they did not remember of the mathematical concepts that would be addressed. The research shows that origami is a great material to be used by the kindergarten teacher in their teaching practice in the classroom to achieve the learning of figures and geometric concepts, and origami allows the student to learn geometry and develop it skills you will use throughout your life. It should also be considered that the proposal of the extension course is configured as an educational product of this dissertation.
Correlation between structure and optical properties of lead metasilicate glass-ceramic under high hydrostatic pressures
(Universidade Federal de São Carlos, 2022-09-21) Pena, Rafaella Bartz; Pizani, Paulo Sérgio; https://lattes.cnpq.br/1038437165007849; https://lattes.cnpq.br/0504471791023003
Glass structures are determined by not only composition, pressure, and temperature but also by the pressure and thermal histories in which the glass was submitted. In this thesis, a systematic study of these variables was performed in undoped and cobalt-doped lead metasilicate (PbSiO3) glasses and mainly probed by Raman spectroscopy. High pressure was applied in a Diamond Anvil Cell (DAC), and the samples were studied ex-situ and in-situ. Ex-situ Raman investigation appoints for an unusual increase in the non-bridging oxygens (NBO) population, at the expense of the bridging oxygens (BO) population, leading to slight depolymerization of the densified metasilicate structure. In-situ investigation of this glass under pressure suggests the densification mechanisms occurring via the formation of an intermediary more polymerized state. Such modifications are accompanied by a change in the lead environment with the formation of highly coordinated PbOn polyhedra. High-temperature investigations were performed in isothermal and non-isothermal runs, providing evidence that the phase evolution from the glass to the stable alamosite is intermediated by two metastable crystalline phases, with a temperature-dependent crystallization path. For the same composition submitted to extremal conditions, the controlling of these structures may offer vast possibilities to tailor the glass-ceramic optical properties.