Silica Nanoparticles
Mostrando 1-12 de 72 artigos, teses e dissertações.
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1. Efficient Encapsulation and Controlled Release of N,N-Diethyl-3-methylbenzamide (DEET) from Oil-in-Water Emulsions Stabilized by Cationic Nanocellulose and Silica Nanoparticles
Oil-in-water emulsions containing N,N-diethyl-3-methylbenzamide (DEET) were developed aiming to extend the sustained release of the active compound, by using two oppositely charged nanomaterials, namely silica nanoparticles (SiNP) and cationic cellulose nanofibrils (CCNF), as stabilizers, and a mixture of food-grade nonionic surfactants to avoid precipitatio
Journal of the Brazilian Chemical Society. Publicado em: 2023
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2. Atomic Absorption Spectrometry as an Alternative to Determine the Presence of Gold Nanoparticles on or in Silica Matrix
Two different gold-silica-based nanomaterials were prepared: (i) silica-supported gold nanoparticles (AuNP/SiO2); and (ii) gold-silica core-shell nanoparticles (AuNP@SiO2). Three strategies for sample treatment (S), consisting in acid treatments, were employed: (S1) HNO3; (S2) HNO3 + HCl; and (S3) HF + HNO3 + HCl, applying microwave oven digestion for S2 and
Journal of the Brazilian Chemical Society. Publicado em: 2022
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3. Biogenic synthesis of silver nanoparticles from thyme extract for functionalization of a bioactive glass produced from rice husk ash
Abstract The rice husk, agro-industrial residue, stands out for having silica, the main oxide former of the bioactive glass. To avoid contamination in this biomaterial, substances with bactericidal properties, like silver can be incorporated. Thus, the objective of this work is the synthesis of silver nanoparticles to functionalize a bioactive glass synthesi
Cerâmica. Publicado em: 2022
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4. CONSTRUÇÃO DE MINI FORNO PARA FUNCIONALIZAÇÃO TÉRMICA DE FASES ESTACIONÁRIAS MONOLÍTICAS
The present work describes a mini oven built to be applied in the preparation of monolithic stationary phase through the thermal polymerization approach. The developed device was successfully tested for functionalization of monolithic stationary phase in the internal surface of the silica capillary column fused with gold nanoparticles.
Quím. Nova. Publicado em: 2020-03
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5. EVALUATION OF SILICA NANOPARTICLE COLLOIDAL STABILITY WITH A FIBER OPTIC QUASI-ELASTIC LIGHT SCATTERING SENSOR
Abstract Colloidal silica is an important biocompatible, inert and non-toxic material for imaging, therapy, and drug delivery biomedical applications. In this context, the evaluation of colloidal suspensions and their stabilities by a Fiber Optic Quasi-Elastic Light Scattering sensor is proposed. Two different silica nanoparticles were prepared and character
Braz. J. Chem. Eng.. Publicado em: 13/01/2020
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6. 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
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7. Síntese e caracterização de nanopartículas de Fe3O4@SiO2
RESUMO Neste trabalho foi estudada a síntese e caracterização das nanopartículas magnéticas de magnetita (Fe3O4) através da co-precipitação e, sua posterior funcionalização pela sílica (SiO2), realizada via metodologia sol-gel. A caracterização das nanopartículas foi feita por difratometria de raios X (DRX), microscopia eletrônica de transmiss
Matéria (Rio J.). Publicado em: 25/11/2019
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8. Synthesis of Highly Ordered Mesoporous MCM-41: Selective External Functionalization by Time Control
Sol-gel synthesis is commonly used to modify the surface of mesoporous silica nanoparticles (MSN) with organic groups through the co-condensation method. The template removal, and the site-controlled addition of organic groups and their partial occlusion inside the framework walls are still a challenge in the one-pot synthesis. Here, we optimize the synthesi
J. Braz. Chem. Soc.. Publicado em: 12/08/2019
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9. An Alternative and Simple Method for the Preparation of Bare Silica Nanoparticles Using Sugarcane Waste Ash, an Abundant and Despised Residue in the Brazilian Industry
Sugarcane waste ash, a Si-rich waste product, is generated in large quantities and creates a serious disposal problem in the Brazilian ethanol-sugar industry, affecting the environment and public health. Here, a simple method capable of generating bare silica nanoparticles utilizing this residue is demonstrated. Firstly, the crystalline silica present in sug
J. Braz. Chem. Soc.. Publicado em: 04/07/2019
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10. 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
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11. Síntese e avaliação de nanopartículas de sílica mesoporosas na liberação controlada de feromônios repelentes de abelha
Resumo Neste estudo foi avaliado o armazenamento e liberação de feromônios repelentes de abelhas em uma nanoestrutura de sílica mesoporosa. O nanomaterial foi sintetizado via método sol-gel e caracterizado por microscopia eletrônica de transmissão, espectroscopia de infravermelho e método BET. As nanopartículas mesoporosas apresentaram-se com área
Cerâmica. Publicado em: 06/06/2019
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12. Avaliação da atividade antimicrobiana e adsortividade de nanopartículas de sílica dopadas com CuO
RESUMO Nanomateriais exibem propriedades que se aplicam nas mais variadas áreas, entre estas, na área da saúde e agrícola, nas quais as pesquisas vêm aumentando progressivamente. Neste trabalho sintetizamos nanopartículas de sílica não porosas dopadas com óxido de cobre (CuO) usando método de Stöber com pequenas modificações. Em adição, a ativ
Matéria (Rio J.). Publicado em: 20/05/2019