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Eletrodeposição de filmes do tipo Ni-X (X=P, Cu ou Cu-P) a partir de banhos contendo aspartato
(Universidade Federal de São Carlos, 2022-11-25) Brito, Matheus Macedo de; Carlos, Ivani Aparecida; https://lattes.cnpq.br/1666217445807782; https://lattes.cnpq.br/8347006546156618
In the present work, aspects related to the electrodeposition of Ni-based metal films - either pure metal or Ni-P, Ni-Cu, and Ni-Cu-P alloys - from baths containing aspartate complexes as electroactive species and hypophosphite anion as the source of phosphorus for the alloys containing this element were addressed. Stable solutions were obtained at pH 6.0, which allowed the formation of the desired codeposits, with the P content in the Ni-P alloy ranging from 15 to 22%, the Cu content in the Ni-Cu alloy ranging from 13 to 22%, while in the Ni-Cu-P alloy, the P content ranged from 1 to 3% and the Cu content was in the range of 24 to 43%, depending on the current density applied for electrodeposition. It was observed that the process efficiencies were affected by the presence of P and Cu, with the former leading to a decrease and the latter leading to an increase in this parameter. The morphology of the films that did not contain Cu was always smooth, with few or no grain boundaries visible by microscopy, while the alloys containing Cu showed the formation of dendritic structures on the electrode surface. Surface composition analysis revealed the presence of Ni(II) oxides in all samples, Cu(II) in Ni-Cu and Ni-Cu-P alloys, and, in the films containing P, the presence of oxidized P(III) and P(V) species were observed. The deposition condition of -60 mA cm-2 with a total load of 40 C cm-2 was selected to produce films for corrosion tests, with the Ni-P film showing superior corrosion resistance in NaCl medium than the Ni-Cu and Ni-Cu-P films, which are shown to be better than the Ni film. The higher corrosion resistance of the Ni-P film was correlated to the presence of surface Ni(II) and P(V) species, which act as a protective layer.
Quantificação e caracterização de microplásticos na atmosfera de São Carlos – SP
(Universidade Federal de São Carlos, 2022-11-25) Ferraz, Gabriel Marcondes; Zucolotto, Valtencir; https://lattes.cnpq.br/5768000922241088; Urban, Roberta Cerasi; https://lattes.cnpq.br/7313670290572985; https://lattes.cnpq.br/6318943182846470
With the rampant use of plastics, combined with the annual increase in its production, a large generation of waste is often incorrectly disposed of, resulting in plastic pollution in the environment, including macro, micro, and nanoplastic pollution. Therefore, the present work aimed to quantify and characterize physical and chemically atmospheric MPs in the city of São Carlos. For this purpose, samples containing MPs were collected, using active and/or passive sampling, indoors and outdoors Doutor Álvaro Guião State School. In the outdoors, the mean concentrations of MPs in the samples were 0.82 ± 0.73 fragments m-3 using an active sampler, and 38.69 ± 20.89 fragments m-2 day-1 and 1.26 ± 0, 88 fibers m-2 day-1 in the dry season, and 25.63 ± 25.51 fragments m-2 day-1 and 0.29 ± 0.51 fibers m-2 day-1 in the rainy season using a passive sampler. Indoors, using passive sampling, the mean concentration was 39.84 ± 22.43 fragments m-2 day-1 and 18.08 ± 6.09 fibers m-2 day-1 in the dry period, and 10.52 ± 17.95 fragments m-2 day-1 and 7.56 ± 4.55 fibers m-2 day-1 in the rainy season. Statistically significant seasonal variation was verified indoors for both morphologies. In addition, fiber concentrations, in the dry and rainy periods, were higher indoors compared to outdoors. The fragments determined in the samples were smaller than the fibers regardless of the type of sampling and whether in an outdoor or indoor ambient. The colors were variable in both morphologies. The built prediction model, the PLS-DA model, for the 12 classes (PS, PC, PET, PLA, Polyester, PP, PU, PE, PLA, Ethylene-Octene,, EVA and MCE Filter) with 11 Latent Variables allowed the explanation of 88.48% of the variance found, with an overall Mean Squared Cross Validation Error of 7.36 ± 6.16%. The majority component of the MPs was Polyester/PET, determined in 100% of the samples. Its proportion ranged from 29 to 100%, followed by EVA (0 to 57%), PE (0 to, 14%) and Ethylene-Octene (0 to 5%). The MPs ubiquity has been demonstrated, as well as the importance of more studies on atmospheric MPs and their implications on the environment and health.
Tendência de HIV Aids entre adultos no Brasil: de 2010 a 2017
(Universidade Federal de São Carlos, 2022-11-25) Ceratti, Amanda; Uehara, Sílvia Carla da Silva André; https://lattes.cnpq.br/3903413440784581; https://lattes.cnpq.br/7122576428082503; https://orcid.org/0000-0002-0236-5025
Objective: to analyze the trend of AIDS incidence coefficients and possible points of changes in adults aged 20 to 59 years in Brazil from 2010 to 2017. Method: ecological study of temporal and local series, with data referring to the period from 2010 to 2017, collected at the Department of Informatics of the Unified Health System and on the page from the Brazilian Institute of Geography and Statistics. The cases were divided by regions in Brazil, gender and age group, and to analyze changes in annual incidences by gender and age group, a joinpoint regression model was used. Results: AIDS showed a growing trend among males aged 20 to 29 years in Midwest, Northeast and North regions and remained, for the most part, stationary in the other age groups in both sexes. Conclusion: the need to strengthen Primary Health Care in its role in preventing HIV infection, as well as early detection of seropositive cases and initiation of treatment before reaching AIDS stage; and to expand access to specialized services in other regions beyond of the Southeast and South. Prevention actions and guidelines aimed at the male audience should be stimulated, and also discussed in the school environment, on an ongoing basis, with young people.