On the basis of their behaviour under mechanical stress or in electric fiel
ds, the aluminosilicate aerogels belong to the intelligent materials. The a
erogels present stronger piezoelectric effect than the xerogels, the reason
for that can be found in the gel structures. The data describing the gel s
tructure obtained by SAXS, SANS, and porosity measurements show a very good
agreement. (C) 2000 Elsevier Science B.V. All rights reserved.