We review recent results on the effect of a specific type of quenched disorder on well known O(m)-vector models in three dimensions: the XY model (3DXY, m = 2) and the Ising model (3DIS, m = 1). Evidence of changes of criticality in both systems, when confined in aerogel pores, is briefly referenced. The 3DXY model represents the universality class to which the λ-transition of bulk superfluid 4...

We describe a set-up for studying adsorption of helium in silica aerogels, where the adsorbed amount is easily and precisely controlled by varying the temperature of a gas reservoir between 80 K and 180 K. We present validation experiments and a first application to aerogels. This device is well adapted to study hysteresis, relaxation, and metastable states in the adsorption and desorption of f...

Carbon aerogels prepared at different carbonization temperatures and with varying mesopore volumes were used as supports for Pt catalysts to study the n-C4H10/H2 reaction. Mean Pt particle size depended on the mesopore volume of the support, showing a linear decrease when the mesopore volume increased. The turnover frequency (TOF) for hydrogenolysis was much higher than for isomerization in cat...

Polymer architecture allows control of thermoreversible gelation in branched copolymer-stabilised emulsions.

Silica aerogels are materials well suited for high power nonlinear optical applications. In such regime, the non-trivial thermal properties may give rise to the generation of optical shock waves, which are also affected by the structural disorder due to the porous solid-state gel. Here we report on an experimental investigation in terms of beam waist and input power, and identify various regime...

An a.c. calorimetric study has been carried out on octylphenylthiolpentyloxybenzoate (8ÂS5) in three silica aerogels with mass densities r=0 0́8, 0 1́7 and 0 3́6 g cm Õ 3 . Results for the least porous aerogel (r=0 3́6) are completely consistent with those reported previously for 8CB in the same aerogel. Freezing of 8ÂS5 damaged the more porous r=0 0́8 and 0 1́7 aerogels by creating internal voids an...

With the merits of quantum dots (QDs) (e.g., high molar extinction coefficient, strong visible light absorption, large specific surface area, and abundant functional active sites) aerogels self-supported architectures, porous network), semiconductor QD show great prospect in photocatalytic applications. However, typical gelation methods rely on oxidative treatments QDs. Moreover, remaining orga...

Abstract Polymer gels are an important class of soft materials with growing interest for biomedical applications due to their distinctive properties. These three‐dimensional polymer networks capable imbibing large amounts solvent while maintaining solid‐like behavior. can be classified into hydrogels, aerogels, and cryogels based on structural features. Their highly porous structure, swelling c...