The safety of nuclear reactors is very important.

The use of this machine is simple.

Heavy water is used as a coolant in nuclear reactors.

Please refrigerate the beer.

This refrigeration system is very efficient.

This computer can be used by anyone.

This furnace operates very efficiently.

Understanding the structure of atoms is a fundamental part of physics.

In this factory, they melt iron using an electric arc furnace.

He developed a famous chemical agent.