A variety of fumed oxides such as silica, alumina, titania, silica/alumina (SA), silica/titania (ST), and alumina/silica/titania (AST) were characterized. These oxides have different specific surface areas and different primary particle composition in the bulk and at the surface. These materials were studied by FTIR, NMR, Auger electron spectroscopy, one-pass temperature-programmed desorption with mass spectrometry control (OP TPDMS), microcalorimetry, and nitrogen adsorption. Nonlinear changes in the surface content of alumina in SA and AST and titania in ST and AST samples with increasing oxide content along with simultaneous changes in their specific surface area cause complex dependencies of the heat of immersion in water and desorption of water on heating on the structural parameters. Simultaneous analysis of changes in the surface phase composition, in the concentration of hydroxyls, and in the structural characteristics reveals that at a low content of the second phase the structural characteristics (e.g., S(BET)) are predominant; however, at a large content of these oxides the phase composition plays a more important role.
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http://dx.doi.org/10.1016/j.jcis.2007.05.025 | DOI Listing |
Nanomaterials (Basel)
December 2024
Center for Genomics and Precision Medicine, Institute of Bioscience and Technology, Texas A&M Health Science Center, Houston, TX 77030, USA.
Our group has synthesized a pleiotropic synthetic nanozyme redox mediator we term a "pleozyme" that displays multiple enzymatic characteristics, including acting as a superoxide dismutase mimetic, oxidizing NADH to NAD, and oxidizing HS to polysulfides and thiosulfate. Benefits have been seen in acute and chronic neurological disease models. The molecule is sourced from coconut-derived activated charcoal that has undergone harsh oxidization with fuming nitric acid, which alters the structure and chemical characteristics, yielding 3-8 nm discs with broad redox potential.
View Article and Find Full Text PDFNanotechnology
January 2025
Faculty of Art and Sciences, Department of Chemistry, Yildiz Technical University, 34220 Istanbul, Turkey.
In this work, a novel composite anode material was developed, utilizing S-doped graphene oxide (SGO), polypyrrole (PPy), and fumed silica to enhance the performance of lithium-ion batteries (LIBs). The chronoamperometric approach was used to produce SGO, while the chemical method was employed to synthesize PPy. A composite of SGO, PPy, and fumed silica was prepared as an anode for a half-cell, using two samples: one with a high PPy ratio (S1) and the other with a low PPy ratio (S2) and compared the results with bare sample (S0).
View Article and Find Full Text PDFSmall
December 2024
School of Chemistry and Chemical Engineering, South China University of Technology, Guangdong, 510640, China.
Solid amine adsorbents designed for capturing trace amounts of carbon dioxide (CO) offer a promising approach. However, developing solid amine adsorbents that concurrently exhibit high oxidative stability and superior CO adsorption capacity remains a significant challenge. Here, ED-PEI/PEG@FS-TBP, an innovative and highly stable CO adsorbent is introduced.
View Article and Find Full Text PDFJ Appl Oral Sci
September 2024
Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba, Departamento de Odontologia Restauradora, Piracicaba, SP, Brasil.
Objective: this study sought to evaluate the effect of isobornyl methacrylate (IBOMA) as a diluent monomer on the physicochemical properties of experimental flowable resin composites.
Methodology: the organic resin matrix of a modal flowable resin composite was formulated with 50 wt.% of bisphenol-A-glycidyl methacrylate (Bis-GMA) and 50 wt.
ChemSusChem
January 2025
Department of Chemical, Pharmaceutical and Agricultural Sciences, University of Ferrara, via Fossato di Mortara 17, 44121, Ferrara, Italy.
A Li-ion battery combines a cathode benefitting from Sn and MnO with high sulfur content, and a lithiated anode including fumed silica, few layer graphene (FLG) and amorphous carbon. This battery is considered a scalable version of the system based on lithium-sulfur (Li-S) conversion, since it exploits at the anode the Li-ion electrochemistry instead of Li-metal stripping/deposition. Sn and MnO are used as cathode additives to improve the electrochemical process, increase sulfur utilization, while mitigating the polysulfides loss typical of Li-S devices.
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