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Showing 1 to 14 of 14 for “"silica aerogels"”.
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High temperature annealing for structural optimization of silica aerogels in solar thermal applications
… transparent, thermally insulating monolithic silica aerogel, with its high solar transmittance and low thermal conductivity, is well-suited for solar thermal applications, particularly concentrated solar power systems. The properties of silica aerogel are directly determined by the structure …
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OIL SPILL CLEANUP BY HYDROPHOBIC SILICA AEROGELS AND SPILLED OIL INTERACTION WITH SUSPENDED SEDIMENTS
Silica aerogel is a promising adsorbent for oil spill cleanup. To make it an economic and environmentally-friendly adsorbent, the effectiveness of thermal regeneration of silica aerogels is investigated in this study. After hydrocarbon desorption at 80 °C, the adsorption capacities of regenerated …
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Modeling, fabrication and optimization of optically transparent - thermally insulating silica aerogels for solar thermal applications
… assumed material properties can be fabricated, silica aerogels were procured, synthesized and characterized. Due to their naturally high and low transmissivities in the solar and IR spectrums, respectively, silica based aerogels coated on the back with highly absorbing (black) surfaces offer a …
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Preparation of silica aerogels with improved mechanical properties and extremely low thermal conductivities through modified sol-gel process
Reported silica aerogels have a thermal conductivity as low as 15 mW/mK. The fragility of silica aerogels, however, makes them impractical for structural applications. The purpose of the study is to improve the ductility of aerogels while retain the low thermal conductivity of silica aerogels. We …
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Experimental and ANSYS investigation on the aerogel envelopes for energy-efficient building
… to reduce the heat loss in buildings or homes. Silica aerogels have grown in popularity as an insulating material due to their extremely low thermal conductivity. Very often the benefits of transparency as well as strength is ignored due to its brittleness. An effort has been taken to increase …
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Energy relaxation in disordered insulators irradiated by ultrafast protons: a multiscale approach
… long transient opacity observed in borosilicate glasses under proton irradiation. We also discuss the application of the model to other materials by performing sensitivity analysis tests.<br/><br/>In the phenomenological model, we assume that the electron-hole plasma becomes homogeneous …
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Investigation and Characterization of Composite Silica Aerogel Nanostructures Obtained Via Magnetron Sputtering
… the deposition of Copper (Cu) onto hydrophilic Silica Aerogel (SA) monoliths using magnetron sputtering, with Cu thicknesses of 20 nm, 50 nm, and 100 nm. Leveraging the mesoporous nanostructure of SA, a Cu-sputtered SA nanocomposite was fabricated, creating a non-homogeneous nanocomposite …
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Truss core sandwich panels with compacted aerogel insulation
Silica aerogels are well known for their low thermal conductivity, approximately 15 mW/m-K. Their low relative density (typically less than 5%) reduces conduction through the solid and their small pore size, typically less than one hundred nanometers, on the order of the mean free path of air, …
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Nanomorphology dependent optical and mechanical properties of aerogels
<p>"Aerogels are very low density, light weight open pore materials. A hypothesis that is under intense current investigation by the scientific community states that the mechanical properties of nanostructured polymers depend on their nanomorphology. Aerogels are nanostructured ultra-lightweight …
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Aerogels and films through free radical polymerization
"Aerogels are porous lightweight materials, unique among all solids in terms of low density, low thermal conductivity, low dielectric constants and high acoustic attenuation. The penalty for those exceptional properties is fragility. That issue has been addressed by bridging covalently …
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Isocyanate-derived organic aerogels: polyurethanes, polyureas, polyamides and polyimides
"Aerogels are 3D assemblies of nanoparticles with high open porosity and high surface area, and are pursued for their low density, low thermal conductivity, low dielectric constant and high acoustic attenuation. The foundation for those exceptional properties is their complex hierarchical solid …
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Characterization of Methyltrimethoxysilane Sol-Gel Polymerization and the Resulting Aerogels.
Methyl-functionalized porous silica is of considerable interest as a low dielectric constant film for semiconductor devices. The structural development of these materials appears to affect their gelation behaviors and impact their mechanical properties and shrinkage during processing. 29Si solution …
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From interfacial nanostructures to advanced constructs: harnessing surfactant self-assembly at liquid interfaces
… viability assays. Finally, the incorporation of silica nanoparticles into a material system previously established for soft matter 3D printing is presented, which was shown to result in the formation of aerogels with significantly enhanced mechanical strength and stability. Such silica aerogels, …
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Light and Heat Selective Polymer Nanocomposite Films for Sustainable Greenhouses
… this reason quantum dot (QD) nanoparticles and silica aerogel (SA) granules were investigated as potential filler materials for the enhancement of the optical and thermal properties of poly (ethylene-vinyl acetate) (EVA), a common greenhouse plastic, for the concurrent goals of increasing …