Gel Phase
Mostrando 1-12 de 1294 artigos, teses e dissertações.
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1. 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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2. 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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3. Biphasic 0.8BaTiO3/0.2Ni(1-x)CoxFe2O4 nanopowders by in situ sol-gel synthesis
Abstract Nanopowders of the 0.8BaTiO3/0.2Ni(1-x)CoxFe2O4 (x=0, 0.25, 0.5, 0.75, and 1) were synthesized by the in situ sol-gel method using poly(acrylic acid) (PAA1800) as a chelating agent. The synthesis developed using PAA1800 ensured the simultaneous crystallization of two phases. The results provided a reliable method for producing biphasic nanopowders i
Cerâmica. Publicado em: 2022
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4. Analysis and evaluation of structural properties of Co3O4 microparticles obtained at low temperature
Abstract In the present research, the synthesis of cobalt oxide Co3O4 was carried out using the sol-gel technique with subsequent heat treatment at 225 and 235 °C. The final product obtained was characterized by X-ray diffraction (XRD), showing a pure crystalline phase of Co3O4, cell parameters a=b=c=8.071 Å, and a volume of 525.7 Å3. The particle size wa
Cerâmica. Publicado em: 2022
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5. Study of Crystallization and Composition on Silicon Oxycarbide (SiOC) and Silicon Boron Oxycarbide (SiBOC) Ceramics Obtained from Alkoxysilanes Precursors
This work deals on the preparation of silicon oxycarbide (SiOC) and silicon boron oxycarbide (SiBOC) ceramics from pyrolysis involving alkoxysilanes with different organic groups. Boron content, organic substituent and annealing time were evaluated on crystallization and composition of resulting ceramics. B-free precursors composed of methyltriethoxysilane (
J. Braz. Chem. Soc.. Publicado em: 2021-06
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6. Serologic strategy in detecting RHD altered alleles in Brazilian blood donors
ABSTRACT Background: We evaluated different technological approaches and anti-D clones to propose the most appropriate serologic strategy in detecting the largest numbers of D variants in blood donors. Methods: We selected 101 samples from Brazilian blood donors with different expressions of D in our donor routine. The tests were performed in immediate spi
Hematol., Transfus. Cell Ther.. Publicado em: 2020-10
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7. MECANISMO DE EVOLUÇÃO DE HIDROGÊNIO DURANTE A CORROSÃO DA LIGA 2198-T8 EM MEIO CONTENDO CLORETO: UMA ABORDAGEM ELETROQUÍMICA
Corrosion is still one of the most serious and frequent problems in industries. The phenomena involved in the corrosion mechanism of Al-alloys may be explained by formation of galvanic cells between the metal matrix and heterogeneities, such as precipitates, intermetallic phases leading to potential differences and electrochemical reactions. In the cathodic
Quím. Nova. Publicado em: 2020-09
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8. Preparation and characterization of yttria stabilized zirconia (YSZ) films deposited by dip-coating on LSM-YSZ substrate with different proportions
ABSTRACT In this work, sol-gel/dip-coating process for obtaining yttria stabilized zirconia (YSZ, ZrO2–8% Y2O3) films deposited onto LSM-YSZ (lanthanum strontium manganite (LSM, La0.7Sr0.3MnO3) mixed with YSZ) with different proportions (20/80, 50/50, 80/20) was investigated. The films were deposited on substrate varying the number of layers deposited. LSM
Matéria (Rio J.). Publicado em: 25/11/2019
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9. Synthesis of Hybrid Monolithic Columns Using a Click Chemistry Reaction for Application in Capillary Liquid Chromatography
Hybrid monolithic columns present characteristics of both silica and organic monoliths, such as good mechanical properties, wide pH tolerance, high permeability and stability and little swelling or shrinkage. A common way to prepare this type of material is by using alkoxysilanes and organic monomers via the sol-gel process and click chemistry reactions. In
J. Braz. Chem. Soc.. Publicado em: 24/10/2019
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10. Transferrina como marcador de maturação pulmonar em cordeiros nascidos a termo ou prematuros
RESUMO O objetivo do estudo foi procurar proteínas de fase aguda que possam indicar sinais de maturação no neonato prematuro, por meio da quantificação sérica delas. Identificou-se a imunoglobulina A, a ceruloplasmina, a haptoglobina, a glicoproteína ácida, a transferrina, a albumina e as imunoglobulinas G de cadeias leve e pesada, pela comparação
Arq. Bras. Med. Vet. Zootec.. Publicado em: 10/10/2019
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11. POTENTIAL OF AUTOCHTHONOUS SULFATE-REDUCING MICROBIAL COMMUNITIES FOR TREATING ACID MINE DRAINAGE IN A BENCH-SCALE SULFIDOGENIC REACTOR
Abstract Biological acid mine drainage treatment depends significantly on inoculum origin, pH, COD/sulfate ratio, and carbon source. In this study, the performance and microbial diversity of anaerobic batch reactors used for sulfate reduction was evaluated. A medium COD/sulfate ratio of 1.14 ± 0.10 was used, and the evaluation was performed in two steps: Ph
Braz. J. Chem. Eng.. Publicado em: 30/09/2019
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12. Urea-based polymethacrylamide purification
ABSTRACT A purification procedure of polymethacrylamide (PMAm) based on the urea feature of being a powerful Hbond breaker is proposed here. Polymethacrylamide was synthesized in water and the final product presents itself as an insoluble gel what is an obstacle to purification. This physical gel, kept together by numerous interchain H-bonds between amide gr
Matéria (Rio J.). Publicado em: 16/09/2019