The system is unique in that it forces the two wythes or layers of concrete to act together structurally, creating a thinner panel.

The outer layer of our skin normally acts as a barrier, protecting inner layers from irritants and infection.

The dense layers of atmosphere at that depth had great propelling power and acted upon the sail with considerable force.

It is important to have an even layer of compound to act as a bed for the tape.

The organic layer also acts to dissipate heat.

The middle layer acts as an insulator to maintain the temperature difference.

A layer acts like a transparent sheet upon which any number of shapes and shape groups can be placed.

The layer can also act as a release agent, helping the product separate from its mould.

The colder layer acted as a cushion pushing against the warm current above.

A layer of sea ice will act as an insulation blanket.