The Advanced Groove System (AGS) is a mechanical coupling assembly system in the 14- to 24-inch pipe size range. The system consists of flexible and rigid couplings, fittings, valves, and accessories.

Some of the most well-known phenomena in molecular and solid-state physics result from the coupling between electrons and phonons. The resistivity of metals, ferroelectricity, Peierls and Jahn–Teller ...