Silica Particles
Mostrando 1-12 de 132 artigos, teses e dissertações.
-
1. Per-Aqueous Liquid Chromatography for the Separation of Polar Compounds Preparation and Characterization of Poly(ethylene oxide co dimethylsiloxane) Based Stationary Phase
Poly(ethylene oxide-co-dimethylsiloxane) was thermally immobilized on silica particles-Si(PEO)-to separate small polar compounds with water-rich mobile phases. Poly(ethylene oxide-co-dimethylsiloxane) content on Si(PEO) stationary phase was optimized using a central composite design. Infrared spectroscopy, scanning electron microscopy, and thermogravimetric
Journal of the Brazilian Chemical Society. Publicado em: 2022
-
2. Magnetic and Mesoporous Silica-Niobia Material as Modifier of Carbon Paste Electrode for p-Nitrophenol Electrochemical Determination
In the present work, the sol-gel synthesis method was employed as strategy to obtain a magnetic and mesoporous silica-niobia material. The planned synthesis was based on the hetero-condensation of niobium and silicon alkoxide precursors, in the presence of spherical magnetite particles. The resulting material presented interesting characteristics such as mag
J. Braz. Chem. Soc.. Publicado em: 2021-03
-
3. Effect of nano-silica on Portland cement matrix
Resumo O uso de nanopartículas é uma tendência recente que pode assumir um papel importante para melhorar o desempenho mecânico do cimento Portland. O objetivo deste estudo é avaliar o efeito da nanossílica na matriz de cimento Portland. A distribuição do tamanho das partículas da matriz de cimento Portland foi modificada pela incorporação de 11,
Rev. IBRACON Estrut. Mater.. Publicado em: 13/12/2019
-
4. CATALYTIC OXIDATION OF ISOPROPYL ALCOHOL OVER PLATINUM BASED CATALYST: A STUDY OF THE EFFECT OF METHYL CELLULOSE ON Pt PARTICLES DISPERSION OVER MULLITE
Abstract Isopropyl alcohol (IPA) catalytic oxidation remains one of the most popular techniques to remove volatile organic compounds from indoor places. In our study, catalytic oxidation of IPA was investigated on catalysts based on platinum deposited on mullite (Al6Si2O13), known for its excellent thermal stability. Pt/Al6Si2O13 catalysts were prepared by i
Braz. J. Chem. Eng.. Publicado em: 09/12/2019
-
5. Weathering Resistance of Waterborne Polyurethane Coatings Reinforced with Silica from Rice Husk Ash
Abstract: Waterborne polyurethanes (WPUs) are interesting materials for coatings when compared to solvent-based polyurethanes, once that reducing the concentration of volatile organic compounds that are harmful for human health and the environment. However, the WPU has low weathering resistance. In order to improve this behavior among others properties, ino
An. Acad. Bras. Ciênc.. Publicado em: 25/11/2019
-
6. Análise da redução da alcalinidade de compósitos cimento-madeira em função da substituição parcial do cimento Portland por pozolanas
RESUMO O objetivo desta pesquisa foi avaliar a redução da alcalinidade de compósitos cimento-madeira, produzido com cimento Portland e partículas residuais de Pinus spp., em função da substituição gradual do cimento Portland pelas pozolanas sílica ativa (SA) metacaulim (MK), cinza volante (CV), escória de alto-forno (EAF), cinza de casca de arroz (
Matéria (Rio J.). Publicado em: 25/11/2019
-
7. Evaluation of the stiffening mechanism based on micro-sized particle inclusions in laminated composites
Rigid particles have been incorporated into laminated composites, especially to enhance their bending performance attributed to the stiffening of the matrix phase (i) and the increased interlaminar shear resistance (ii). In order to better evaluate the improvement mechanism provided by the particulate inclusions, this work investigates the incorporation of m
Mat. Res.. Publicado em: 17/10/2019
-
8. Rheological Parameters of Shear-Thickening Fluids Using an Experimental Design
Abstract: The influence of important factors related to fluid preparation on shear-thickening fluids (STF) is not well explored in literature. Thus, this paper aimed at analyzing the statistical significance of experimental conditions, such as fumed silica concentration (Cs), stirring time (tst), stirring speed (Sst) and sonication time (tso ), on the rheolo
Mat. Res.. Publicado em: 14/10/2019
-
9. Obtaining and characterizing dental hybrid composites with clay or silica nanoparticles and boron-aluminum-silicate glass microparticles
Abstract The aim of the present work was the obtaining and characterization of dental hybrid composites using nanoparticles (clay or silica) and boron-aluminum-silicate microparticles. We evaluated the dispersion of the nanofillers when changing their loading among 2.5%, 5%, 10% and 25% wt. Were tested, in the above quantities, four different types of nanofi
Polímeros. Publicado em: 27/06/2019
-
10. Influence of Crystallization and Ageing Time on the Reproducibility of Mesoporous Molecular Sieve SBA-15
ABSTRACT The study aimed to assess how the crystallization and ageing times in SBA-15 synthesis influence the reproducibility and particle size of mesoporous molecular sieves. X-ray diffraction showed that higher crystallization times provide greater reproducibility of mesoporous silica, due to the fact that there is no significant variation in the width and
Matéria (Rio J.). Publicado em: 10/06/2019
-
11. Synthesis of ordered mesoporous silica MCM-41 with controlled morphology for potential application in controlled drug delivery systems
Resumo O MCM-41 é uma das cerâmicas mesoporosas mais estudadas para sistemas de liberação controlada de fármacos. Sua elevada área superficial específica e mesoporosidade permitem alta capacidade de adsorção. Apesar dos inúmeros trabalhos publicados na área biomédica, até o presente momento não há relatos de aplicações comerciais do MCM-41.
Cerâmica. Publicado em: 06/06/2019
-
12. Determination of the optimal replacement content of Portland cement by stone powder using particle packing methods and analysis of the influence of the excess water on the consistency of pastes
Resumo O cimento Portland é considerado o componente de base com o maior impacto ambiental na construção civil, em termos de emissões de CO2. Quanto aos agregados, o processo de cominuição das rochas, além da areia artificial, gera pó de pedra que acaba sendo armazenado ao ar livre, gerando impactos ambientais. Assim, a substituição do cimento por
Rev. IBRACON Estrut. Mater.. Publicado em: 20/05/2019