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Estudo teórico e experimental da interação de elétrons com moléculas de interesse astroquímico
(Universidade Federal de São Carlos, 2021-09-08) Mata, Victor Augusto Santana da; Souza, Gabriel Luiz Cruz de; https://lattes.cnpq.br/2821352329397835; Homem, Manoel Gustavo Petrucelli; https://lattes.cnpq.br/2059356773212608; https://lattes.cnpq.br/3324231784334779
We performed a theoretical and experimental investigation on electron (e⁻) scattering by molecules of astrochemical interest. Theoretically, we obtained elastic differential (DCSs), integral (ICSs) and momentum-transfer (MTCSs) cross sections, total (TCSs) and total absorption (TACSs) cross sections for electron collisions with cyanoacetylene (HC₃N), acetonitrile (CH₃CN), isocyanic acid (HNCO), chloroform (CHCl₃), and chlorobenzene (C₆H₅Cl) molecules in the 0.1 to 1000 eV incident electron energy-range (E₀) by using ePolyScat codes (D and E3 versions). Presently, important developments in E3 version were performed in order to include the account of absorption effects (already present in D version). Thus, one uses a complex optical potential to represent the e⁻-molecule dynamics. In the methodology applied by ePolyScat, the wave function and the interaction potentials are single-center expanded, and the scattering equations are solved iteratively with the Padé’s approximants technique. The effectiveness of the modification in ePolyScat-E3 is verified by the good agreement with experimental data and other theories. Calculations were also performed using the independent atom model (IAM). Experimentally, DCSs data were obtained for E₀ from 20 up to 800 eV applying the relative flow technique (RFT) for chloroform and chlorobenzene. In the E₀ < 50 eV region, DCSs data were also measured at CSUF by Prof. M. A. Khakoo in collaboration, allowing the comparison between the theoretical and experimental data in a large energy range (0.5 ≤ E₀ ≤ 800 eV). Obtaining DCSs for non-chlorinated molecules was made impossible by COVID-19 pandemic. Nonetheless, a significant experimental advance was performed, making possible the synthesis of HC₃N samples at UFSCar. For such molecule, we obtained but one set of DCSs at E₀ = 20 eV. We generally observe a good agreement between the theoretical and experimental results obtained in the present work and other data available.
Aço inoxidável duplex de baixa liga, S32101: uma visão tecnológica sobre resistência mecânica, impacto, corrosão localizada e microestrutura
(Universidade Federal de São Carlos, 2021-09-08) Ferezin, Tiago Daniel; Rovere, Carlos Alberto Della; https://lattes.cnpq.br/8141224513975606; Ferrante, Maurizio; https://lattes.cnpq.br/6067173982945625; https://lattes.cnpq.br/1061696500866543
The applications of duplex stainless steels are growing steadily in fields such as the paper, foodstuff, chemical and petrochemical industries. However, one drawback is cost, mainly due to the presence of Ni and Mo. Recently, by the total or partial replacement of by N and Mn, both strong austenite stabilizers, the so-called lean duplex stainless steel´s family was developed. As a consequence of the new composition some properties are changed with respect to the conventional duplex steels, of which the S32205 is the most widely known. The present work is meant to be a comprehensive study of the S32101 steel, in which microstructure, tensile and impact properties, and corrosion behaviour in FeCl3.6H2O, were investigated on welded joints produced by the TIG process, in which two different heat inputs, 1.3 and 0.9 kJ/mm, were employed. Additionally, the weld cooling rate was measured in the ZTA and bending tests were performed. Results showed that the microstructure was almost unaffected by the weld cycle, regardless the cooling rate. In the ZTA the α/ ratio was larger than one, and in the weld metal was slightly biased towards austenite. A fine precipitation of Cr2N was detected in the ferritic regions of the ZTA’. Tensile strength of the welded joint was higher than that of the S32205 steel, with the fracture always taking place in the weld metal. The impact energy of the weld metal produced with the higher heat input (sample AA) was equal to 72 J, that is, almost 85% higher than that of sample BA. However, the ZTA impact energy was much lower and was unaffected by the different heat inputs. The fracture surfaces show weld metal with normal appearance, that is, shear lips and brittle areas, base metal with delaminations, and ZTA with similar features, suggesting that the crack, originally located in the ZTA, may have been deflected towards the base metal. As for the corrosion behaviour, although pits were observed main along the ZTA of both samples, the one with the higher heat input was more affected.
Determinantes da eficiência técnica da produção de cana-de-açúcar brasileira
(Universidade Federal de São Carlos, 2021-09-08) Coelho, Luísa Fancelli; Bragagnolo, Cassiano; https://lattes.cnpq.br/3604206454925741; https://lattes.cnpq.br/2510196634205211
Brazil is currently the world’s largest producer of sugarcane and the importance of this sector has been occurring since the colonial period and has strengthened its relevance in the international market. The increase on the interest of sugarcane reflects an international demand for clean energy and the growing concern with the reduction of greenhouse gases turning Brazil a relevant pole of production. Due to the economic, social and environmental importance that the production of sugarcane and ethanol exert on Brazil, an analysis of the efficiency of these sectors was carried out. The efficiency measure was performed using the data envelopment analysis (DEA). The objective was to calculate the technical efficiency in the production of sugarcane for a sample of municipalities in the states of São Paulo, Goiás, Minas Gerais and Mato Grosso using data from the 2017 Agricultural Census, released by the Brazilian Institute of Geography and Statistics (IBGE, 2017). Additionally, a Tobit model was used to identify the socioeconomical variables affecting sugarcane production efficiencies. There was a concentration of sugarcane production in the mesoregions of Ribeirão Preto and São José do Rio Preto in São Paulo and Triângulo Mineiro/Alto Paranaíba in Minas Gerais. The results pointed that the municipalities with the biggest proportion of rural credit use had higher levels of efficiency in São Paulo. Minas Gerais showed a significant and positive influence regarding to the revenue from sugarcane. The state of Goiás was the only one that showed a positive influence of smallholder farms on efficiencies, while the state of Mato Grosso was the only one that showed positive significance for the average age of the population.
Efeito da melatonina sobre marcadores teciduais e séricos de dano muscular esquelético induzido por exercício físico
(Universidade Federal de São Carlos, 2021-09-08) Infante, Nick Alexandre; Beck, Wladimir Rafael; https://lattes.cnpq.br/3124811889307056; https://lattes.cnpq.br/5112511180624317
Physical exercise can cause muscle damage, commonly called exercise-induced muscle damage (DMIE), triggering several events which will initiate the repair process of this tissue through the activation of satellite cells (CS). The transcription factor PAX7 is used as a CS marker, being expressed during the quiescence, activation and proliferation of these cells. The literature presents some therapeutic resources aimed at reducing damage or even accelerating the muscle repair process, acting on inflammation or oxidative stress. With anti-inflammatory, anti-apoptotic and antioxidant actions, melatonin could be used as one of these therapeutic resources. Experiment I aimed to identify the best prescription for the skeletal muscle damage (PID) induction protocol, using 35 Wistar rats divided into 7 groups: control (CL), protocol 1 (P1), protocol 2 (P2), protocol 3 (P3), protocol 4 (P4), protocol 5 (P5), protocol 6 (P6). The morphological changes found in the white portion of the gastrocnemius muscle through the hematoxylin and eosin technique, the greater depletion in the glycogen content of the same muscle, 24 hours after exercise (P1 -25.24%) compared to the CL group and the high concentrations serum creatine kinase MM (CK-MM) (592.19±190.23 U/L) during the same period demonstrate the efficiency of P1 in causing skeletal muscle damage and justifies its choice for PID. Experiment II aimed to analyze the effects of melatonin on tissue and serum markers of physical exercise-induced skeletal muscle damage, comprising 70 Wistar rats divided into 7 groups: control group (CL), which received vehicle solution (ethanol and NaCl) and were euthanized at 98 days of age and six groups which received melatonin or not immediately after the PID and were euthanized 24, 48 or 72 hours after the exercise (E24), (E48), (E72), (EM24), (EM48) and (EM72). Blood was collected to analyze the concentration of CK-MM and lactate dehydrogenase and white gastrocnemius for quantification of PAX7 expression by immunofluorescence. Data were presented as mean and standard deviation, and the One-way or two-level factorial ANOVA tests were performed with Newman-Keuls post hoc when necessary, as well as the dependent and independent t test, assuming a significance level of 5%. There was an effect of time on serum CK-MM concentrations in animals euthanized 48 hours (F=3.27; p<0.05) compared to rats euthanized 24 and 72 hours after PID. The EM48 group, on the other hand, showed a significant reduction (p=0.010) in the concentrations of this enzyme compared to the E48 group. There was a reduction in PAX7 expression in animals that received melatonin compared to animals that received vehicle solution (F=13.90; p=0.001). Melatonin was able to reduce muscle damage demonstrated by the decrease in the serum concentration of CK-MM, also resulting in a reduction in the expression of PAX7.
Geografia e inovação: o Parque Tecnológico de Sorocaba e as alterações na estrutura industrial da região administrativa de Sorocaba
(Universidade Federal de São Carlos, 2021-09-08) Oliveira, Willian Prestes de; Silva, Carlos Henrique Costa da; https://lattes.cnpq.br/5444248390841543; https://lattes.cnpq.br/2123422609321128
This thesis aims to understand how much the actions of the State authority in Sorocaba benefited the municipality and the region in the process of productive restructuring in the state of São Paulo, ensuring the attraction of industries, especially sectors of greater technological intensity to settle in the territory. For the development of the research, it is guided by the authors who deepen the entitled The Geography of Innovation also highlighting the discussions on the attraction factors of industrial activity, the constituent elements of innovation systems, Local Productive Arrangements, and regional innovation systems. It directly addresses elements already established in the region, such as transport infrastructure and higher education institutions, and also those recently created by the State authority in the region of Sorocaba, which makes it an area of interest for the development of industrial activity and for the improvement of regional culture of innovation, highlighting the Sorocaba Technological Park created to serve as a space for interaction between universities, research institutions and companies linked to the technology sector. Ultimately, it undertakes a comprehensive survey of data referring to recent economic transformations in the city and in the Administrative Region of Sorocaba through the data from the IBGE and the RAIS/CAGED platform, analyzing the evolution of the productive structure of Sorocaba using the classification of industrial activities by level of technological intensity, based on the parameters established by the OECD and CNAE 2.0, with greater emphasis on the High Technological Intensity, Medium-High Technological Intensity sectors, jointly considering data on the evolution of the numbers of establishments, sectoral participation in the value of State industrial transformation and on labor in the period of 2008 and 2018.