01. Universidade Federal Rural de Pernambuco - UFRPE (Sede)
URI permanente desta comunidadehttps://arandu.ufrpe.br/handle/123456789/1
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Resultados da Pesquisa
Item Investigação das modificações químicas de biomarcadores de petróleo submetidos a derrames simulados em ambientes aquáticos(2021-12-15) Oliveira, Milton Neto Nascimento de; Santos, Jandyson Machado; http://lattes.cnpq.br/4137257750865101; http://lattes.cnpq.br/4629247582941612The oil industry characterizes a source of risks to the environment. Studies that aim to understand the chemical modification in oil spill situations are gaining greater attention due to recurrent environmental disasters, such as the one that occurred on the coast of Brazil in 2019. The purpose of this study was to apply a laboratory simulation of oil spills in aquatic environments, to evaluate the chemical changes in composition of oils using the technique of gas chromatography coupled to mass spectrometry (GC/MS) and infrared spectroscopy (IR). For the simulations, a homemade system was used that were a chamber with white, blue and ultraviolet lamps, referring to wavelengths like those emitted by solar radiation, where inside was allocated a mixture of oil and seawater 1:80 (m/v), and the oil spill simulation was performed to obtain aliquots of oil at different times of exposure. The oil aliquots were analyzed by GC/MS, in order to obtain a comparative analysis of the initial crude oil (control) and the same oil after the spill exposures, which was possible to evaluate the chemical changes of oil biomarkers and their diagnostic reasons. The chromatograms showed a decrease in the peak areas of the n-alkanes with lower molecular weight in the first hours of exposure to the simulated spill, however, no significant changes were observed in the diagnostic ratios for biomarkers of the sterane and terpane classes, showing that they are classes that do not change chemically. The IR was performed in the spectral range of 600-4000 cm-1, using attenuated total reflectance (ATR). The IR data showed peaks related to the majority chemical composition of crude oils, referring to aliphatic hydrocarbon compounds. It was also possible to identify peaks related to the appearance of new stretching linked to chemical changes associated with the photo-oxidation process that occurred in the spill simulation, referring to peaks for oxygenated compounds, in the region of 1233 cm-1. Thus, the study was able to identify some changes in the chemical composition of crude oils after simulated spills in aquatic environments, as well as to show that the consolidated diagnostic ratios involving terpanes and steranes do not change, and in both cases can be used in studies to track oil spills in environments and/or as data for remediation of environments impacted by spills involving the oil industry.Item Análises químicas e bioquímicas em plantas(2019) Arruda, Antonio Diego Rosa de; Barreto, Levy Paes; http://lattes.cnpq.br/5714315066729620Item Desenvolvimento de métodos de digestão empregando ácido diluído e de análise química por EDXRF para a batata-doce(2019-07-11) Andrade, Thaís Barreto Mendes de; Gomes, Maria José de Filgueiras; França, Elvis Joacir de; http://lattes.cnpq.br/1716496767364751; http://lattes.cnpq.br/0060810526769648; http://lattes.cnpq.br/9151550124239566Item Análise de Parabenos empregando Quantum Dots(2019-07-11) Araújo, Arthur Luís Silva de; Lavorante, André Fernando; http://lattes.cnpq.br/1011018535020717; http://lattes.cnpq.br/0168928366474354Cosmetics are products widely present in daily life of modern society. Because of this fact, public and private policies emphasize a necessity of great quality input generation, low cost, and mainly, nontoxic formulations. The high strict on cosmetics quality control has injected capital in sector, becoming the “top” of Fine Chemistry in several regions. This status has keeping itself up, for products which follow mainly Green Chemistry principles, where the masterpiece must be completely used during production process, making the smallest residue as possible. Among the most stuck-level inside sector, are use of preservatives (natural or synthetic) on products in general, which could show side effects somehow. Therefore, the work’s goal was propose an alternative method to analyze an organic preservatives group (parabens), potentially toxic, in cosmetics e suchlike products distributed in Pernambuco State. Its high microbial inhibition power makes these preservatives doses have been administered in traces-concentration. Currently the only method of parabens quantification is by Gas Chromatography (laborious technique and elevated maintenance cost). As an alternative, choose quantum dots (QDs) use to spectrofluorimetric determination of the analytes. This type of methodology is fast, sensible, selective, reproductive and has shown itself promising to parabens detection. The proposed work shows a review about cosmetics, parabens and nanoparticles. In the experimental stage, the parabens synthesis was accomplished, their description as well and analyze preliminary tests with quantum dots. On parabens description realized that those were synthesized with success. Posteriorly, employed AgInS2-GHS to obtain an analytical curve based on fluorophore’s luminescence quenching, varying parabens concentration between 0,0 and 50,0 mg L-1, making satisfactory results [yAPHB = 0,0030(±0,005)x + 0,9825(± 0,0002); R = 0,9932 / yMetPa = 0,0049(± 0,0003)x + 0,9407(± 0,0116); R = 0.9925) demonstrating the feasibility of the proposed method for parabens analysis.