He is an expert in chemistry.

This area is seriously contaminated with radioactive isotopes.

This area is affected by radioactive fallout from past nuclear tests.

An isotope refers to elements with the same atomic number but different numbers of neutrons.

Rare earth elements are essential materials for the manufacture of electronic devices.

Transition elements play an important role in chemical reactions.

Electromagnetic radiation conveys energy in forms such as light and radio waves.

He is receiving treatment for brain radiation.

A cooling device utilizing the principle of radiative cooling has been developed.

His nature is very kind.