2. Glossary

actuator

System capable of producing mechanical work under the action of an external stimulus.

adsorption

Phenomenon by which atoms or molecules attach themselves to a solid surface.

aerogel

A gel in which the liquid (or solvent) located in the interstices of the solid parts has been replaced by air. The liquid network has been transformed into a network of pores.

aerosol

Suspension, in a gaseous medium, of liquid or solid particles (or both), with negligible falling velocity. In air, under normal conditions, an aerosol is made up of particles ranging in size from fractions of a nanometer to 100 µm.

AES (Auger electron spectroscopy)