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Biofertilizantes como reatores em grânulo: sistemas carreadores com Aspergillus niger e Trichoderma asperelloides para ações no controle biológico, promoção do crescimento de plantas e solubilização de fósforo
(Universidade Federal de São Carlos, 2021-10-14) Favaro, Camila Patrícia; Farinas, Cristiane Sanchez; https://lattes.cnpq.br/9933650905615452; https://lattes.cnpq.br/0893621842906330
In recent years, the importance of microorganisms role in maintaining agricultural productivity has been highlighted, being essential in cycling nutrients and production of metabolites to contribute to plant growth and protection. All these factors contribute to growth of biological products market. However, studies are still needed to improve and develop production technologies and maintain the quality of these products. Associating the use of unprocessed phosphate rocks (PR) with the microbial P solubilization, we developed a process to produce a biofertilizer granule from cold extrusion, capable of scaling. The granule acts as a micro reactor, where the nutrient of formulation supports microorganism growth for production of metabolites capable of solubilizing the phosphorus (P) of rock, biological control, and plant growth promotion. In the first stage of this work, the P solubilization have been evaluated by Aspergillus niger and Trichoderma spp. isolated and combined in submerged cultivation, using different phosphate rocks powder. At this stage, the strains, and the PR to be used in the development of the granule were selected. The production of the biofertilizer granules process was developed, with the isolated and combined strains. In the biofertilizer granule, an increase of up to 150% in the solubilization of P was observed when compared to the cultures with phosphate rock powder. The antagonism in vitro of the biofertilizer with Fusarium oxysporum demonstrated the capacity of T. asperelloides for biological control. The combination with A. niger did not affect its performance of T. asperelloides. Subsequently, aiming to reduce the production costs of biofertilizers granules and reduce the waste generation, the substrate for microorganisms cultivation (rice grains) was used as a nutrient source in formulation. The viability of the formulations in storage at 4 °C and room temperature was evaluated, showing the importance of studying the storage conditions to maintain the quality of the product. Finally, the biofertilizer granules with isolated and combined microorganisms were evaluated in a soil-plant system (rhizotron), analyzing root and plant growth of tomato, and the dynamics of P in soil. The presence of T. asperelloides promote statistically significant differences in plant height. The presence of A. niger generated an increase in P in the fractions that showed greater migration dynamics of this component to the more labile fractions. These results which demonstrated the potential applicability of the product. The production process developed of biofertilizer granule by cold extrusion opens new doors for use of different carrier materials and the development of new granular biological products for direct application in agriculture.
Análise de polaridade e de tópicos em tweets no domínio da política no Brasil
(Universidade Federal de São Carlos, 2021-10-14) Capellaro, Leonardo; Caseli, Helena de Medeiros; https://lattes.cnpq.br/6608582057810385; https://lattes.cnpq.br/1323489363246457
The political scenario in Brazil is one of the busiest and most controversial in the last decade. With the advent of social networks, a new communication channel between voters and politicians was created, with users having a space to publish their opinions, beliefs and also follow the posts of other people. In this context, this work shows the performance of BERT models in the polarity (positive, negative or neutral) and topic analysis of tweets related to Brazilian politics. Experiments were carried out with tweets related to the 2018 elections achieving results (F1 = 96%) better than the ones obtained by previous works for the polarity classification. The qualitative analysis of the topics (the first one using BERTopic in this corpus) also resulted in promising insights.
Síntese da SBA-15 funcionalizada com aminossilanos e sua aplicação na condensação aldólica entre o furfural e a acetona
(Universidade Federal de São Carlos, 2021-10-14) Lima, Marcelo Souza; Marques, Clelia Mara de Paula; https://lattes.cnpq.br/0451284088402660; Gallo, Jean Marcel Ribeiro; https://lattes.cnpq.br/3485408327490746; https://lattes.cnpq.br/1329951278487934
The petroleum is used to manufacture plastics, solvents and, mainly, to produce fuels. However, some factors such as fluctuation in the price of the barrel, its non-renewable origin and the release of greenhouse gases make it necessary to diversify this energy matrix. In this way, furfural, derived from a renewable source, can undergo aldol condensation with ketone and form aviation kerosene precursors. This reaction is catalyzed by acid or base, however, studies in the literature show that heterogeneous catalysts do not have stability, with loss of the material's active phase, suffer from deactivation and, mainly, have low product selectivity (1E,4E)-1,5-di (furan-2-yl)penta-1,4-dien-3-one (F₂Ac). Therefore, in this work, catalysts are proposed in order to increase the efficiency of materials in this reaction. Therefore, in Chapter 1, mesoporous materials of the SBA-15 family were synthesized functionalized with: (3-aminopropyl)triethoxysilane (APTES), 3-(2-Imidazolin-1-yl)propyltriethoxysilane (IMPTES), (3-anilinopropyl)trimethoxysilane (PAPTMS) that would give basic properties to materials. Thus, they were characterized by X-Ray diffraction, Infrared spectroscopy, thermal (TGA) and CHN elemental analysis. In addition, catalytic tests were carried out that investigated the best experimental conditions and revealed that the SBA-15-APTES material has the best activity, fully converting furfural and being 47% selective to the product (1E,4E)-1,5-di (furan-2-yl)penta-1,4-dien-3-one (F₂Ac) of greatest interest and 7% to (E)-4-(furan-2-yl)but-3-en-2-one (FAc). In chapter 2, the synthesis of materials with Sn (IV) is proposed, which would give acidic Lewis properties, aiming to stabilize the enolate anion formed from F₂Ac and functionalized with the aforementioned silanizing agents that confer basicity. Then, the catalysts were synthesized by post-functionalization of Sn-SBA-15 precursor materials and characterized by UV-vis spectroscopy, ICP-OES and by the analyzes already mentioned in the previous chapter. In the catalytic tests all materials were active, however, the results revealed that the acidity did not contribute to the desired action.