handbook of carbon, graphite, diamond and fullerenes

Glossary
Ablation: The removal of material from the surface of a body exposed to
a high-velocity gas such as a reentry nose cone or a rocket motor. Ablation
occurs mainly by decomposition or vaporization resulting from the friction
with the gas and the resulting high temperature.
Activation: A process that increases the surface area of a material such
as charcoal or alumina. In the case of charcoal, the surface of the material
is oxidized and minute cavities are created which are capable of adsorbing
gas atoms or molecules.
Adsorption: The formation of a layer of gas on the surface of a solid (or
occasionally a liquid). The two types of adsorption are (a) chemisorption
where the bond between the surface and the attached atoms, ions, or
molecules is chemical, and (b) physisorption where the bond is due to van
der Waals' forces.
Aliphatic Hydrocarbons: A group of organic compounds having an openchain
structure such as parafin, olefin, acetylene, and their derivatives.
Angular Momentum: The product of moment of inertia and angular
velocity.
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