We developed a peptide-functionalized polydiacetylene nanosensor for pH1N1 virus detection with the naked eye.

Silica aerogels have attracted tremendous interest due to their high specific surface area and the physical, chemical, and mechanical properties as promising materials for thermal insulation, chemical sensors, and energy storage devices. However, large-scale production of silica aerogels remains a challenge due to costly alkoxide precursors and energy-intensive supercritical drying processes. This paper analyzes the effect of acidity levels and feed rate on the porosity of rice husk aerogels with high specific surface area under ambient pressure. This synthetic approach is cost-effective, eco-friendly, and facilitates recycling. Rice husk ash, which consists of 92% amorphous pure silica, was produced by combustion. A process of solvent exchange and surface modification under ambient pressure at different pH levels was conducted for synthesis of the aerogel. The specific surface area of rice husk aerogel was confirmed as ranging from 385 to 861 m²/g under pH 1 to pH 9 and acid feed rate of 0.5 to 5.0 mL/min. The optimized aerogel had a specific surface area of 861 m²/g, a pore volume of 3.33 cm³/g, and an average pore diameter of 12 nm when synthesized at pH 1 and an acid feed rate of 2.5 mL/min. The aerogel was found to be highly hydrophobic, with a water contact angle of 156° up to about 340 °C.

The building has a large impact on the space heating demand and the indoor environment is affected by climate or daylight. Hence, silica aerogel has generally used as a film to reduce the coefficient of the window in the building. Silica aerogel is a suitable material to apply for insulation material with lower thermal conductivity than that of air to save interior energy. However expensive precursor and drying process were the main issue of the silica aerogel synthesis and practical usage. We attempt to fabricate aerogel insulation film for energy saving through the economic process under ambient pressure. Silica aerogel was synthesized from rice husk ash, which was an agricultural waste to be able to recycle. Taguchi design was used to optimize the parameters (amount of rice husk ash, pH, aging time) controlling the surface area of silica aerogel. The silica aerogel is prepared by sol-gel processing through acidic treatment and aging. The silica aerogel was obtained by modification of silica hydrogel surface and dry at ambient pressure. Finally, aerogel film was respectively fabricated by the different content of aerogel in polydimethylsiloxane (PDMS). Silica aerogel obtained 21 – 24nm average particle size was analyzed by SEM and silica aerogel with high surface area (832.26 m²/g), pore size ( 3.30nm ) was characterized by BET. Then silica Aerogel – PDMS insulation film with thermal conductivity (0.002 W/mK) was analyzed by thermal wave system. The study demonstrates an eco-friendly and low-cost route toward silica – PDMS insulation film with low thermal conductivity (0.002 W/mK).