Sio2 Tio2
Mostrando 1-12 de 74 artigos, teses e dissertações.
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1. EVALUATION OF THE PHOTOCATALYTIC ACTIVITY OF SiO2@TiO2 HYBRID SPHERES IN THE DEGRADATION OF METHYLENE BLUE AND HYDROXYLATION OF BENZENE: KINETIC AND MECHANISTIC STUDY
Abstract Silica spheres coated with titania (SiO2@TiO2) were synthesized using chitosan as template. The N2 adsorption/desorption isotherms of the spheres point to meso and macroporous characteristics and the elemental mapping by EDS shows uniform distribution of Ti on the surface of the silica spheres, leading to formation of an amorphous structure (XRD). T
Braz. J. Chem. Eng.. Publicado em: 13/01/2020
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2. Modeling and prediction of sulfuric acid digestion analyses data from PXRF spectrometry in tropical soils
ABSTRACT Sulfuric acid digestion analyses (SAD) provide useful information to environmental studies, in terms of the geochemical balance of nutrients, parent material uniformity, nutrient reserves for perennial crops, and mineralogical composition of the soil clay fraction. Yet, these analyses are costly, time consuming, and generate chemical waste. This wor
Sci. agric. (Piracicaba, Braz.). Publicado em: 04/11/2019
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3. Effects of Heat Treatment and Yb 3+ Concentration on the Downconversion Emission of Er 3+ /Yb 3+ Co-Doped Transparent Silicate Glass-Ceramics
The SiO2-Al2O3-BaF2-TiO2-CaF2 transparent silicate glass-ceramics containing BaF2 nanocrystals were successfully prepared by heat treatment process through conventional melting method. Effects of heat treatment processes and Yb3+ concentration on the downconversion (DC) emission of the co-doped Er3+/Yb3+ transparent silicate glass-ceramics were investigated.
Mat. Res.. Publicado em: 28/10/2019
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4. Characterization of Li2O-Al2O3-SiO2 glass-ceramics produced from a Brazilian spodumene concentrate
Resumo Vitrocerâmicas do sistema LAS (Li2O-Al2O3-SiO2) com elevada resistência ao choque térmico foram obtidas com sucesso com o uso de um concentrado de espodumênio brasileiro como principal matéria-prima (80%-70% em massa). Duas composições (Li2O.Al2O3.nSiO2) foram produzidas com n= 2 e 4, próximas às composições estequiométricas das fases eucr
Cerâmica. Publicado em: 15/08/2019
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5. Solid Phase Extraction Using SiO2/Al2O3/TiO2 Ternary Oxide for Cu2+ Preconcentration
The present work aims at studying the preconcentration of Cu2+ ions by solid phase extraction using SiO2/Al2O3/TiO2 ternary oxide as adsorbent material. This methodology consists of the affinity of the analyte for the adsorbent material and its subsequent elution with the least amount of solvent. Subsequently, the aqueous phase containing the extracted analy
J. Braz. Chem. Soc.. Publicado em: 04/07/2019
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6. Caracterização de argilas de novos jazimentos situados em Parelhas/RN, Brasil, visando aplicação na indústria cerâmica
RESUMO O Estado do Rio Grande do Norte, mais especificamente no município de Parelhas, Brasil, a indústria cerâmica já é bastante consolidada, crescendo ano após ano. Entretanto, o estímulo do setor tem provocado acelerada exaustão das jazidas de argilas locais utilizadas pela indústria e, por conseguinte, ameaçando a manutenção da indústria cer
Matéria (Rio J.). Publicado em: 10/06/2019
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7. Fe3O4-TiO2 and Fe3O4-SiO2 Core-shell Powders Synthesized from Industrially Processed Magnetite (Fe3O4) Microparticles
The interest for core-shells has been increased in the recent years due to their improved and modifiable properties. In this work, Fe3O4-TiO2 and Fe3O4-SiO2 core-shells were successfully synthesized from an industrially produced magnetite-rich powder with micro- and nanometric particle sizes, superparamagnetic behavior and saturation magnetization of 49 emu/
Mat. Res.. Publicado em: 09/05/2019
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8. Caracterização de solos tropicais a baixo custo e tempo usando espectrômetro portátil de fluorescência de raios-X (pXRF): Efeitos de diferentes métodos de preparo de amostras
RESUMO O espectrômetro portátil de fluorescência de raios-X (pXRF) foi recentemente adotado pela Ciência do Solo, para uso em campo e laboratório, para obtenção do conteúdo total de vários elementos químicos em poucos segundos. A digestão com ácido sulfúrico é uma análise laboratorial cara e demorada que fornece teores de Fe2O3, Al2O3, SiO2, T
Ciênc. agrotec.. Publicado em: 2018-02
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9. Synthesis of TiO2/SiO2-B2O3 Ternary Nanocomposites: Influence of Interfacial Properties on their Photocatalytic Activities with High Resolution Mass Spectrometry Monitoring
An investigation on unusual interface properties of unprecedented ternary composites, formed by the inclusion of assorted proportions of B2O3 into TiO2/SiO2 structure, is conducted herein. The influences of B2O3 content and calcination temperature were evaluated. The precursor TiO2/SiO2 material was synthesized via a simple sol-gel procedure that was followe
J. Braz. Chem. Soc.. Publicado em: 2017-10
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10. The Effect of TiO2-SiO2 Nanocomposite on the Performance Characteristics of Leather
In this study the effect of TiO2-SiO2 nanocomposite on various performance characteristics of finished leather was investigated. For this purpose, TiO2-SiO2 nanocomposite was prepared via the sol-gel method from tetraethoxysilane (TEOS) and titanium n-butoxide (TBO) catalyzed with acid at ambient temperature. The prepared composite was applied by spraying on
Mat. Res.. Publicado em: 22/06/2017
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11. Estudo de composições cerâmicas à base de alumina e vitrocerâmico do sistema LZSA para obtenção de estruturas multicamadas por tape casting
Resumo Compósitos de matriz cerâmica têm sido desenvolvidos nas últimas décadas como um meio eficiente de melhoria da tenacidade à fratura. Compósitos cerâmicos multicamadas se destacam por seu relativo baixo custo e facilidade de obtenção. Estes compósitos são confeccionados com camadas alternadas de dois materiais cerâmicos e têm como mecanis
Cerâmica. Publicado em: 2017-04
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12. Photocatalytic Degradation for Treating Multipesticide Residues Using [Ru(bipy)3]Cl2-Doped TiO2/SiO2 Based on Surface Response Methodology
This study aimed to develop and optimize an efficient photocatalytic process employing ruthenium [Ru(bipy)3]2+ doped TiO2-SiO2 for degrading synthetic wastewater containing six classes of pesticides (bentazone, carbofuran, clomazone, diuron, tebuconazole and pyraclostrobin). To optimize the degradation conditions for the six pesticides and assess the effect
J. Braz. Chem. Soc.. Publicado em: 2016-12