Formation Process
Mostrando 1-12 de 5056 artigos, teses e dissertações.
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1. Bioactive SiO2-K2O-CaO-P2O5 glass-ceramic scaffold prepared using polyurethane foam template
Abstract A glass-ceramic in the SiO2-K2O-CaO-P2O5 quaternary system was prepared by substituting the Na2O component with K2O to avoid Na2Ca2Si3O9 formation upon thermal treatment since this phase decreases apatite formation kinetics on glass material. To form the glass-ceramic, a modified sol-gel method involving solution precipitation, followed by reagents
Cerâmica. Publicado em: 2023
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2. Synthesis of delafossite CuCrO2 via solution combustion method and its acid functionalization for biodiesel production
Abstract CuCrO2 was synthesized by solution combustion synthesis (SCS) and applied as a heterogeneous catalyst to produce soybean biodiesel. The combustion reaction was carried out using urea as a fuel, and copper (II) and chromium (III) nitrates as precursors. After the powders’ obtention, these were calcined and functionalized in an acidic medium. The po
Cerâmica. Publicado em: 2023
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3. Tailoring the properties of Y2O3 via synthesis parameters varied during the PVA-assisted sol-gel route
Abstract The effect of synthesis parameters on the microstructural behavior and morphology during the yttrium oxide (Y2O3) formation is reported. Y2O3 crystals were produced by a modified sol-gel route assisted by polyvinyl alcohol solution varying the calcination temperature and solution pH. The crystalline phase formation was investigated using X-ray powde
Cerâmica. Publicado em: 2023
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4. The Contribution of Meteorological Parameters and the COVID-19 Partial Lockdown on Air Quality in Rio de Janeiro, Brazil
This study evaluated the pollutant levels (NO2, SO2, CO, and O3), air quality index (AQI) and the influence of meteorological variables and coronavirus disease (COVID-19) pandemic on the air quality in Rio de Janeiro. The data set used comprises periods before (March-April, 2019) and during pandemic (March-April, 2020). According to the AQI results, on most
Journal of the Brazilian Chemical Society. Publicado em: 2023
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5. Selective formation of neodymium phosphate from iron-neodymium magnet waste
Abstract Neodymium-iron-boron alloy, Nd2Fe14B, is used as a material for magnets. Neodymium is one of the valuable and expensive rare earth elements and is often recovered to reduce costs and environmental impact. Recently, a method for recovering neodymium as neodymium phosphate from mixed solutions was reported. This method was very useful because the main
Cerâmica. Publicado em: 2022
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6. Tuning the Photocatalytic Activity of Tin Oxide through Mechanical Surface Activation
Tin oxide (SnO2) nanoparticles were synthesized by the co-precipitation method and mechanically modified by high-energy ball milling. The experimental results demonstrate that the collision with zirconia balls produces slight changes in the crystalline, electronic, morphological, and surface properties of SnO2, which lead to an increase in the redox potentia
Journal of the Brazilian Chemical Society. Publicado em: 2022
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7. Designing and fabrication of a low-cost dip-coater for rapid production of uniform thin films
In this work, a self-made dip-coater equipment was developed for the fabrication of thin films. The assembly of the apparatus was carried out using simple mechanical and electronic pieces, recycle parts, and spending an inexpensive budget suitably. The production, software design, and features of the device were focused on the sol-gel dip-coating method, whi
Química Nova. Publicado em: 2022
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8. COMPREENDENDO OS MECANISMOS DE CORROSÃO DE LIGAS DE AL-CU-LI: UMA INVESTIGAÇÃO ATRAVÉS DE TÉCNICAS ELETROQUÍMICAS GLOBAIS E LOCAIS
In this study, the corrosion mechanism of an Al-Cu-Li alloy manufactured by two different treatment routes (T3 and T851) was evaluated by immersion and electrochemical tests in solutions containing chloride ions (Cl-). For both alloys, the formation of cavities on the surface was associated with micrometer-sized intermetallics (IM’s), however, in addition
Química Nova. Publicado em: 2022
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9. Diabetes and bone
Abstract Globally, one in 11 adults has diabetes mellitus of which 90% have type 2 diabetes. The numbers for osteoporosis are no less staggering: 1 in 3 women has a fracture after menopause, and the same is true for 1 in 5 men after the age of 50 years. Aging is associated with several physiological changes that cause insulin resistance and impaired insulin
Archives of Endocrinology and Metabolism. Publicado em: 2022
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10. ROBÓTICA EDUCACIONAL, ENSINO DE QUÍMICA E APRENDIZAGEM COOPERATIVA: UMA PROPOSTA PARA O CURSO DE ENSINO SUPERIOR EM ENGENHARIA CIVIL
Students, generally, are afraid of studying chemistry because they understand that it is a very complex area of knowledge and that it doesn’t has use in daily lives and in intended profession, which is a problem we identified in a Civil Engineering course. With this, we proposed a project in this course, based on educational robotics and educational cooper
Química Nova. Publicado em: 2022
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11. Internationalization of China’s medical device industry: a case study in Brazil
Abstract Purpose The singularity of being the first Chinese manufacturer of drug-eluting stents to arrive in Brazil and the country being selected as the company's first experience outside its home country motivated the interest in the study of this case, vis-à-vis with the characteristic of internationalization medical device companies according to the Up
RAUSP Management Journal. Publicado em: 2022
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12. Othering discourse and stigma amidst the identity formation process among gays, bisexuals and other men who have sex with men on HIV pre-exposure prophylaxis (PrEP)
Resumo Com o avanço global da Profilaxia Pré-exposição ao HIV (PrEP) questões sobre a formação do processo (bio)identitário de gays, bissexuais e outros homens que fazem sexo com homens usuários de PrEP complexificam-se para além de expressões de orientação sexual. Realizamos uma análise de conteúdo com categorias temáticas em um grupo online
Ciência & Saúde Coletiva. Publicado em: 2022