Graphite
Mostrando 13-24 de 378 artigos, teses e dissertações.
-
13. GRAPHENE OXIDE AND A GO/ZnO NANOCOMPOSITE AS CATALYSTS FOR EPOXY RING-OPENING OF EPOXIDIZED SOYBEAN FATTY ACIDS METHYL ESTERS
Abstract In this work, the grapheme oxide (GO) and GO/ZnO nanocomposite were successfully obtained from the oxidation of graphite and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and thermogravimetric analysis (TGA). In the GO/ZnO nanocomposite, the GO sheets were coated with aggregated
Braz. J. Chem. Eng.. Publicado em: 09/12/2019
-
14. Silica/Titania Graphite Composite Modified with Chitosan and Tyrosinase Employed as a Sensitive Biosensor for Phenolic Compounds
A mesoporous, high surface area and conductive silica/titania graphite composite modified with chitosan and functionalized with tyrosinase was prepared. The composite was obtained by the sol-gel method and the surface of the resultant material was modified with chitosan solutions containing 5, 10 and 15% by mass. The textural characterization showed that eve
J. Braz. Chem. Soc.. Publicado em: 24/10/2019
-
15. A New Electrochemical Platform Based on a Polyurethane Composite Electrode Modified with Magnetic Nanoparticles Coated with Molecularly Imprinted Polymer for the Determination of Estradiol Valerate in Different Matrices
A polyurethane composite electrode modified with magnetic nanoparticles (mag; Fe3O4) coated with molecularly imprinted polymers (MIPs) was developed for the electrochemical determination of estradiol valerate. Chemical and morphological analyses of the mag-MIP were performed using scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (E
J. Braz. Chem. Soc.. Publicado em: 24/10/2019
-
16. Spatial pattern of the environmental exposure to tin in the vicinity of an alloy industry in Volta Redonda, Rio de Janeiro State, Brazil
Resumo: O estanho é amplamente utilizado na indústria. A literatura sobre seus efeitos em humanos é escassa, principalmente quanto aos valores de referência em indicadores biológicos como sangue e urina. Também são raros os estudos sobre os limites do estanho no meio ambiente. O estudo teve como objetivo avaliar os pontos críticos da distribuição e
Cad. Saúde Pública. Publicado em: 14/10/2019
-
17. Preparação, caracterização e avaliação catalítica do compósito Fe2O3/grafite em reação foto-Fenton
RESUMO Neste trabalho, compósito Fe2O3/grafite foi preparado e usado como um catalisador em reação foto-Fenton para a descoloração de solução aquosa contendo o corante amaranto sob irradiação de luz visível. Amostras com diferentes teores de Fe2O3 suportados sobre grafite foram preparadas e caracterizadas por difração de raios-X (DRX), adsorção
Matéria (Rio J.). Publicado em: 16/09/2019
-
18. Nitretação por descargas elétricas da liga Ti-6Al-4V com adição de pó abrasivo SiC ao fluido dielétrico
RESUMO O processo de nitretação que usa Usinagem por Descargas Elétricas é um método que associa a capacidade de usinar superfícies complexas com a obtenção de tratamento termoquímico de nitretação. A fonte de nitrogênio é proveniente da uréia, que compõe o fluido dielétrico juntamente com água deionizada. A liga de titânio Ti-6Al-4V possui
Matéria (Rio J.). Publicado em: 16/09/2019
-
19. Removal of organic matter from pre-treated domestic sewage in anaerobic biological reactor by a combined system of electrolytic and biological aerobic treatment
Resumo Os processos biológicos são os métodos mais difundidos para o tratamento de águas residuárias. No entanto, eles têm limitações para degradar poluentes tóxicos e refratários, contaminantes, que os processos eletroquímicos podem remover. Portanto, o objetivo da pesquisa foi verificar a possibilidade de tratamento de esgoto por um processo bio
Rev. Ambient. Água. Publicado em: 22/07/2019
-
20. APLICAÇÃO DA ESPECTROSCOPIA RAMAN NA CARACTERIZAÇÃO DE MINERAIS PERTENCENTES A UMA GEOCOLEÇÃO
Lots of Educational Institutions hold their own geocollection due to its utility and versatileness in the practical formation of new generations of skillful professionals in many areas of Science and Technology. The Geoscience laboratory of the Federal University of São Carlos has a collection of minerals used in engineering, mineralogy and other technologi
Quím. Nova. Publicado em: 18/07/2019
-
21. Electrolytic polishing of compacted graphite iron for revealing subsurface graphite of honed cylinders
ABSTRACT The superficial characteristics of honed surfaces are relevant for the tribological performance of cylinders of internal combustion engines (MCI). Recent studies found a correlation between the occurrence of the phenomenon called folded metal and the presence of graphite of cast irons. However, the honing process tends to overlap the graphite, such
Matéria (Rio J.). Publicado em: 20/05/2019
-
22. Assessment of Trace Element Contents in Soils and Water from Cerrado Wetlands, Triângulo Mineiro Region
ABSTRACT In the Brazilian Cerrado biome, there are wetlands locally known as “Veredas”, which are swampy plains between hills and rivers. Since the 1970’s, the Cerrado biome has been gradually converted to livestock, crop, or forestry production. Until now, very few studies were conducted to evaluate the baseline contents of trace elements in Cerrado w
Rev. Bras. Ciênc. Solo. Publicado em: 29/04/2019
-
23. Calibration of high-temperature furnace assemblies for experiments between 200 and 600 MPa with end-loaded piston-cylinder apparatuses
Abstract We present pressure calibration results for piston-cylinder –” and 1” high temperature furnace assemblies in the 200-600 MPa range aiming to expand its applicability to simulate upper crustal conditions. The furnace assemblies were made up by crushable MgO, graphite heater, pyrex glass spacer, and NaCl sleeve. Twenty-one experiments were carri
Braz. J. Geol.. Publicado em: 15/04/2019
-
24. New Synthesis Method for a Core-Shell Composite Based on α-Bi2O3 @PPy and its Electrochemical Behavior as Supercapacitor Electrode
New composite based on polypyrrole (PPy) and bismuth oxide (α-Bi2O3) was investigated as supercapacitor electrode. The α-Bi2O3 was obtained by hydrothermal route at 500 ºC for 2 h. Cyclic voltammetry was used to electropolymerize PPy on graphite electrode (GE) or on GE/α-Bi2O3. The X-ray diffraction profile of Bi2O3 revealed the α-Bi2O3 monoclinic struc
J. Braz. Chem. Soc.. Publicado em: 2019-04