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Comparação entre o método de segmentação supervisionada e não supervisionada de modelos deep learning para identificação de indivíduos Pinus spp. Invasores em área de campo úmido
(Universidade Federal de São Carlos, 2023-12-22) Ferreira, Giovanna de Andrade; Molin, Paulo Guilherme; https://lattes.cnpq.br/1529819650942373; https://orcid.org/0000-0002-4587-935X; https://lattes.cnpq.br/7304255443790304; https://orcid.org/0000-0001-7714-8327
The introduction of Pinus spp. in Brazil, it causes a series of environmental disorders and can lead to the impoverishment of biodiversity through its invasive potential. Thinking about the difficulty of obtaining quantification and geolocation data of individuals, this work aims to compare two deep learning models for automated segmentation of Pinus spp. crowns. The comparison was carried out between a model manually trained by the Mask R-CNN algorithm (supervised classification) and an existing model, SAM (unsupervised classification). Mask R-CNN presented 81% intersection over the union of polygons and 88% overlap rate between the manually delimited Masks and the masks segmented by the algorithm, while SAM presented results of 72% and 77%, respectively. The results found reinforce the importance of studies related to new remote sensing technologies for monitoring native vegetation as a biological conservation tool.
Nanocompósitos magnéticos à base de zeólita obtida a partir da casca de arroz para adsorção de polifenóis da indústria do vinho
(Universidade Federal de São Carlos, 2023-12-22) Neves, Tainara Ramos; Paris, Elaine Cristina; https://lattes.cnpq.br/8475640212486290; https://orcid.org/0000-0001-8599-9674; https://lattes.cnpq.br/9468795660002190; https://orcid.org/0000-0003-3445-3545
In recent years, the wine sector has presented considerable growth, resulting in increased production and, consequently, an increase in the effluents generated during winemaking. Polyphenols stand out among the components present in these effluents due to their analgesic, antimicrobial, and antioxidant properties. However, they can become contaminants in high concentrations. Given this scenario, it is necessary to develop effective methods for recovering these substances and water reuse, emphasizing the adsorption process that permits the reuse of the adsorbed compounds. This project uses rice husks, an agribusiness waste, to obtain zeolite-based magnetic nanocomposites for chlorogenic acid (CGA) adsorption. The synthetic faujasite (FAU) zeolite was initially synthesized and modified with silane agents to optimize the interactions with the polyphenols during the adsorption process with the zeolite nanocomposites obtained from the rice husks. The adsorption tests were carried out using FAU nanostructures silanized with (3-aminopropyl) triethoxysilane (APTES), trimethylchlorosilane (TMCS), and a combination of both under mechanical agitation for 24 h. FAU:APTES:TMCS stood out, showing better performance in the adsorption of ACG (20 mg L-1) compared to FAU without functionalization, achieving removal percentages of 12.78% and 67.80% for FAU and FAU:APTES:TMCS, respectively. The zeolite optimization, using high-purity silica extracted from rice husks, was carried out by investigating the hydrothermal synthesis time to obtain the FAU phase. The FAU phase most evident was in the 18-hour synthesis period (Z18), with a surface area of 217.69 m2 g-1 and a zeta potential of -38.87 mV, indicating stability in aqueous solution. The Z18 zeolite was modified (Z18 M) with the APTES:TMCS silane mixture and used to obtain the magnetic nanocomposites. For immobilizing the zeolites obtained from rice husks, copper ferrite heat-treated at 500ºC (F500) was used due to effective magnetic properties, a lower impurity index, smaller particle sizes, and good stability in aqueous solution. In this respect, the magnetic composites Z18:F500 and Z18 M:F500 showed effective magnetic properties and element distribution along the surface evaluated by energy dispersive X-ray spectroscopy (EDS), achieving GCA adsorption rates of 31.96% and 79.53%, respectively. In this way, it is concluded that silica obtained from rice husks proved an excellent candidate for the sustainable synthesis of zeolites. The zeolite surface modification led to greater efficiency in the recovery of ACG in aqueous media. Finally, the present work presents an alternative for reusing agribusiness waste and recovering polyphenols from wine effluents, contributing to a system capable of magnetic removal in a way that favors the circular economy.