Catalytic Activity
Mostrando 25-36 de 3650 artigos, teses e dissertações.
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25. Screening of the Au:Pt Atomic Ratio Supported in SrCO3: Effects on the Performance of the Solvent-Free Oxidation of Benzyl Alcohol
We have prepared, by a sol-immobilization method, bimetallic catalysts with different Au:Pt atomic ratios supported on commercial SrCO3. The catalytic performance for the oxidation reaction of benzyl alcohol of such materials was compared to the monometallic counterparts, aiming at the obtaining of the best composition of the material. It was found that the
J. Braz. Chem. Soc.. Publicado em: 2020-03
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26. INFLUÊNCIA DA COMPOSIÇÃO DOS NANOFIOS PT-IR/C NA ATIVIDADE CATALÍTICA FRENTE A OXIDAÇÃO ELETROQUÍMICA DE ETANOL EM MEIO ÁCIDO
Carbon-supported platinum-iridium nanowire-shape electrocatalysts containing 20% of metallic loading were synthesized by chemical reduction method using formic acid as a reducing agent and tested towards the oxidation of ethanol in acidic medium. The developed electrocatalysts were synthesized with the following compositions: Pt0.9Ir0.1/C, Pt0.8Ir0.2/C, Pt0.
Quím. Nova. Publicado em: 2020-02
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27. STABILIZATION STUDY OF TETRAMERIC Kluyveromyces lactis β-GALACTOSIDASE BY IMMOBILIZATION ON IMMOBEAD: THERMAL, PHYSICO-CHEMICAL, TEXTURAL AND CATALYTIC PROPERTIES
Abstract We investigated the immobilization of a tetrameric Kluyveromyces lactis β-galactosidase (EC: 3.2.1.23) (KL-Gal) on Immobead 150 using different support modification strategies. Immobead support was modified using an acid solution of H2SO4:HNO3 (3:1) (Immobead-Ac) or 5 % (v/v) glutaraldehyde (Immobead-Glu). Its unmodified form (Immobead) was also te
Braz. J. Chem. Eng.. Publicado em: 13/01/2020
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28. Solvothermal Synthesis of Cerium-Doped Titania Nanostructured Materials Modified with Acetylacetone for Solar-Driven Photocatalysis
This study reports the preparation of nanostructured cerium-doped titanium dioxide photocatalysts containing different cerium concentrations by a modified sol-gel route involving the use of acetylacetone. The nanocrystalline powders had their structural, morphological, and optical properties characterized by X-ray diffraction, vibrational and Raman spectrosc
J. Braz. Chem. Soc.. Publicado em: 2020-01
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29. RE-ESTERIFICATION OF MACAUBA ACID OIL USING GLYCEROL FOR ACIDITY REDUCTION AND BIODIESEL PRODUCTION
Abstract Biodiesel production using acid oils is an important alternative for biofuel cost reduction. However, it is a huge challenge for homogeneous transesterification, the main industrial route commonly used. This paper presents macauba oil with high acidity, 43.90 w/w%, as a potential raw material for biodiesel production. The acidity was reduced to 0.8
Braz. J. Chem. Eng.. Publicado em: 09/12/2019
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30. Heterologous expression and mutagenesis of recombinant Vespa affinis hyaluronidase protein (rVesA2)
Abstract Background: Crude venom of the banded tiger waspVespa affinis contains a variety of enzymes including hyaluronidases, commonly known as spreading factors. Methods: The cDNA cloning, sequence analysis and structural modelling of V. affinis venom hyaluronidase (VesA2) were herein described. Moreover, heterologous expression and mutagenesis of rVesA2
J. Venom. Anim. Toxins incl. Trop. Dis. Publicado em: 05/12/2019
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31. Síntese de CoFe2O4 sobre os suportes MgAl2O4 e ZSM-5 para uso na degradação de poluente orgânico pelo processo foto-Fenton heterogêneo sob irradiação visível e solar
RESUMO Neste trabalho, ferrita de cobalto (CoFe2O4) foi sintetizada sobre aluminato de magnésio (MgAl2O4) e zeólita ZSM-5 e a atividade catalítica desses materiais na reação foto-Fenton visando a decomposição de um poluente orgânico em solução aquosa foi avaliada. Ferrita de cobalto foi sintetizada sobre os suportes pela rota solvotérmica. Os mate
Matéria (Rio J.). Publicado em: 25/11/2019
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32. Iridium-Based Catalysts for the Ethanol Electrooxidation in Acidic Media
Herein we sinthesize and investigate Ir-based nanocatalysts (dispersed in carbon) in different atomic compositions combining two (IrRh) and three metals (IrRhSn). These materials were evaluated towards the ethanol electrooxidation in acidic electrolyte in presence of three ethanol concentrations using cyclic voltammetry, while the species produced during the
J. Braz. Chem. Soc.. Publicado em: 21/10/2019
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33. Direct Assay to Evaluate Phosphoenolpyruvate Carboxykinase Activity
Phosphoenolpyruvate carboxykinase (PEPCK) is a ubiquitous enzyme found in all known groups of organisms, acting in the reversible conversion of oxaloacetate (OAA) to phosphoenolpyruvate (PEP) in the presence of divalent metal ion, and dependent of adenosine 5’-triphosphate (ATP) or guanosine-5’-triphosphate (GTP). PEPCK is an important enzyme in the meta
J. Braz. Chem. Soc.. Publicado em: 21/10/2019
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34. Facile One-Step Electrodeposition Fabrication of Amorphous MoS2 Catalysts in Titanium for Hydrogen Evolution Reaction
Hydrogen is seen as a future energy carrier that will assist the global energy fuel demand. However, it is still necessary to study efficient and inexpensive catalysts that can be used on a large scale to make this technology practical. In this paper the electrodeposition of molybdenum disulfide (MoS2) film on titanium (Ti) substrate was performed by cyclic
J. Braz. Chem. Soc.. Publicado em: 21/10/2019
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35. Physicochemical Study of the Interaction between Gold Nanoparticles and Lipase from Candida sp. (CALB): Insights into the Nano-Bio Interface
The surface interactions between gold nanoparticles (AuNPs) and lipase from Candida antarctica fraction B (CALB) were investigated at macromolecular and colloidal length-scales. In order to elucidate the reciprocal effect of the interactions on the individual component’s properties, CALB was either added during the synthesis of AuNPs or added to pre-synthe
J. Braz. Chem. Soc.. Publicado em: 21/10/2019
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36. REMOVAL OF NITRATE FROM DRINKING WATER BY USING PdCu STRUCTURED CATALYSTS BASED ON CORDIERITE MONOLITHS
Abstract Structured catalysts were prepared, characterized and evaluated in NO3 - removal from drinking water. Different suspensions containing a previously optimized PdCu/5wt% ZrO2-Al2O3 powder catalyst (hereinafter PdCu/5ZAp) were prepared and deposited on cordierite monoliths by washcoating. The effect of suspension concentration, the particle size, the i
Braz. J. Chem. Eng.. Publicado em: 30/09/2019