Fourier
Mostrando 13-24 de 2324 artigos, teses e dissertações.
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13. Physicochemical and sensory characteristics of dehydrated coffee pulp in function of drying temperature
RESUMO Atualmente, uma das opções da utilização da polpa de café é a preparação de infusões com base na mesma, cujas propriedades antioxidantes foram avaliadas. O objetivo deste estudo é avaliar o efeito da temperatura de secagem nas propriedades químicas da polpa de café desidratada, bem como caracterizar física e sensorialmente a bebida da pol
Revista Brasileira de Engenharia Agrícola e Ambiental. Publicado em: 2022
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14. Use of glass waste in the production of metakaolin-based geopolymer submitted to room temperature and thermal curing
Resumo O metacaulim é a principal matéria-prima utilizada na síntese de geopolímeros, embora a relação entre os teores de sílica e alumina não seja a ideal. Normalmente, o teor de SiO 2 é ajustado com o uso de silicatos presentes na solução ativadora. Uma opção ecoeficiente seria o uso de resíduos de vidro como fonte adicional de sílica. Este
Ambiente Construído. Publicado em: 2022
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15. A química analítica aplicada aos estudos de pigmentos rupestres: uma revisão
Instrumental advances have been employed in the study of archeological remains such as prehistoric rupestrians paintings with the objective of chemically characterizing them in order to reconstruct the cultural technologies of a prehistoric human group and/or to support conservation science studies. The analytical techniques most commonly used in archaeometr
Química Nova. Publicado em: 2022
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16. Friedelane Triterpenes with Cytotoxic Activity from the Leaves of Maytenus quadrangulata (Celastraceae)
Three new triterpenes, 3,4-seco-3,11β-epoxyfriedel-4(23)-en-3β-ol (1), friedelan-3α,11β diol (2), 7β,26-epoxyfriedelan-3a,7a-diol (3), a mixture of two new triterpenes 3α-hydroxyfriedelan-29-yl palmitate (4) and 3α-hydroxyfriedelan-29-yl stearate (5) and eleven known compounds were obtained from the hexane extract of Maytenus quadrangulata leaves. The
Journal of the Brazilian Chemical Society. Publicado em: 2022
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17. Remoção de chumbo (II) de solução aquosa por nanopartículas magnéticas (MnFe2O4) funcionalizadas com poliestireno sulfonado
RESUMO O presente estudo contempla a aplicação de nanopartículas magnéticas de ferrita de manganês MnFe2O4 (NPM) modificadas com poliestireno sulfonado (PSS) na adsorção de íons de Pb (II) para fins de tratamento de água contaminada. A funcionalização da nanopartícula com o polímero objetivou aumentar a capacidade de adsorção e incluir a utili
Engenharia Sanitaria e Ambiental. Publicado em: 2022
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18. The influence of separately and combined bentonite and kaolinite as binders for pelletization of NaA zeolite from coal fly ash
Abstract Pelletization of zeolitic materials is required to facilitate their practical industrial and commercial applications. Zeolite-NaA was synthesized from fly ash by the fusion method and shaped into spherical granules. Bentonite, kaolinite, and a combination of bentonite with kaolinite were tested as binders with different contents from 5 to 10 wt%. Th
Cerâmica. Publicado em: 2022
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19. Preparation and performance of magnetic zirconium-iron oxide nanoparticles loaded on palygorskite in the adsorption of phosphate from water
Magnetic zirconium-iron oxide nanoparticles loaded on palygorskite as a low-cost adsorbent was produced by one-step co precipitation technique and its properties for phosphate adsorption were overall investigated. The Brunauer Emmett Teller (BET) specific surface area analysis, scanning electron microscopy (SEM), thermo gravimetric analysis (TGA), Fourier tr
Química Nova. Publicado em: 2022
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20. Enhancement of Visible Light-Responsive Photocatalytic Efficiency by Using a Laccaic Acid-Modified Titanium Dioxide Photocatalyst
In this study, a laccaic acid-modified TiO2 photocatalyst (Lac-TiO2) was prepared via an impregnation method with 0.50, 1.00, 2.50, and 5.00 wt.% laccaic acid. The products’ physical properties were examined through X-ray powder diffraction (XRD), field emission scanning electron microscopy (FE-SEM), X-ray photoemission spectroscopy (XPS), UV-Vis diffused
Journal of the Brazilian Chemical Society. Publicado em: 2022
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21. Thermal treatment of poultry litter: Part II. Evaluation of structural and morphological characteristics
RESUMO Este estudo teve como objetivo investigar o efeito dos tratamentos térmicos no volume total dos poros, na área superficial dos poros, nas características estruturais e nos grupos funcionais dos materiais derivados da carbonização e pirólise da cama de aviário. Esses processos foram realizados em recipientes de porcelana contendo amostras de cam
Revista Brasileira de Engenharia Agrícola e Ambiental. Publicado em: 2022
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22. Enhancing glass ionomer cement features by using the calcium phosphate nanocomposite
Resumo Este estudo apresenta a síntese de cimentos de ionômero de vidro (GIC) modificados com nanopartículas de fosfato de cálcio (nCaP). Os nCaP / GIC foram submetidos a ensaios mecânicos de compressão e tração diametral. Os biocompósitos foram caracterizados por microscopia eletrônica de varredura (MEV), espectroscopia de energia dispersiva de ra
Brazilian Dental Journal. Publicado em: 2022
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23. Production of nanostructured crystalline composite using residual ashes from flocculated sludge burning process in a poultry slaughterhouse wastewater treatment system
Abstract Nanostructured crystalline composite (activated carbon) was synthesized from residual ashes of the burning process of the sludge generated in the flotation step of a poultry slaughterhouse and was used for Allura red dye adsorption. The ashes were chemically activated using two types of reagents, H2O2 and H3PO4, and the structure, morphology, and su
Cerâmica. Publicado em: 2022
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24. Iron Cobaltite (FeCo2O4) Nanocatalysts for Water-Oxidation: Effects of Annealing Temperature on Catalytic Properties
The development of efficient, stable, and non-precious metal water oxidation catalysts (WOCs) is a matter of importance for sustainable energy research. In this work, iron cobaltite (FeCo2O4) nanoparticles were prepared by the coprecipitation method, and we present the effect of heat treatment (250, 350, 450, 650 and 900 °C) on the catalytic properties. Cat
Journal of the Brazilian Chemical Society. Publicado em: 2022