Even though aerosol injection into stratosphere is one of the most promising solar geoengineering techniques, sulfate aerosols, which are suggested for such an application, show significant drawbacks as infra-red (IR) absorption and ozone degradation. The development new materials application that would exhibit substantial up-scattering, with non-IR to allow a cooling effect needed. Here, novel...

Abstract The mechanical properties of SiO 2 aerogel prepared under atmospheric pressure are poor, so it is difficult to prepare large pieces materials for practical engineering. In this paper, trimethylchlorosilane (TMCS) was used as a surface modifier transform hydrophilic substances with higher activity into hydrophobic groups, improve the network strength aerogel. Super-hydrophobic by sol-ge...

We present a theoretical study of the phase diagram and the structure of a fluid adsorbed in high-porosity aerogels by means of an integral-equation approach combined with the replica formalism. To simulate a realistic gel environment, we use an aerogel structure factor obtained from an off-lattice diffusion-limited cluster-cluster aggregation process. The predictions of the theory are in quali...

The incorporation of silica aerogel particles into the isocyanate used to prepare Rigid Polyurethane composite foams drastically modifies its rheological behaviour. changes from being a Newtonian fluid constant viscosity (0.3 Pa s at 25 °C) non-linear power-law material with complex decreasing 104 101 slope −1 versus frequency. change in response is caused by formation percolated network conten...

Abstract Silica aerogel is the ultimate thermal insulator thanks to its record-breaking low conductivity (?), open porosity and hydrophobicity. aerogel's lowest at intermediate densities (? ? 0.11 g/cm3) and, because of strong, power-law dependence E modulus on density, this rather density so far led moduli. Even with polymer reinforcement, increasing stiffness only possible higher thus conduct...

Silicon nanoparticles of three types (oxide-terminated silicon nanospheres, micron-sized hydrogen-terminated porous silicon grains and micron-size oxide-terminated porous silicon grains) were incorporated into silica aerogels at the gel preparation stage. Samples with a wide range of concentrations were prepared, resulting in aerogels that were translucent (but weakly coloured) through to compl...

Positronium yield using the “3γ method” and lifetime measurements were performed at cryogenic and room temperature by means of a variable energy positron beam in homogeneous porous silica (Aerogel). An estimation of the positronium (Ps) mean diffusion length was obtained by measuring capped samples. An efficient formation of cooled Ps atoms is a requisite for the production of antihydrogen, wit...