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Glossary U - Z
URadTown Glossary
a | b | c | d | e | f | g | h | i | j | k | l | m | n | o | p | q | r | s | t | u | v | w | xyzUnstable Nucleus
An atom is unstable (radioactive) if the forces among the particles that make up the nucleus are unbalanced, that is to say, if the nucleus has an excess of internal energy. See also stable nucleus.
Uranium
A naturally occurring radioactive element whose principal isotopes are Uranium-238 and Uranium-235.Natural uranium is a hard silvery-white shiny metallic ore that contains a minute amount of Uranium-234.
Uranium mill Tailings
Naturally radioactive residue from the processing of uranium ore. Although the milling process recovers about 95 percent of the uranium, the residues, or tailings, contain several naturally-occurring radioactive elements, including uranium, thorium, radium, polonium, and radon.
RadTown Glossary
a | b | c | d | e | f | g | h | i | j | k | l | m | n | o | p | q | r | s | t | u | v | w | xyzW
RadTown Glossary
a | b | c | d | e | f | g | h | i | j | k | l | m | n | o | p | q | r | s | t | u | v | w | xyzX Y Z
RadTown Glossary
a | b | c | d | e | f | g | h | i | j | k | l | m | n | o | p | q | r | s | t | u | v | w | xyzX-Rays
High-energy electromagnetic radiation emitted by atoms when electrons fall from a higher energy shell to a lower energy shell. These rays have high energy and a short wave length. X-rays are very similar to gamma rays.