Download Glossary of Key Terms in Chapter Two

Denniston, 7e
Glossary of Key Terms in Chapter Nine
alpha particle (9.1) consists of two protons and two neutrons (the alpha particle is identical to helium
nucleus).
artificial radioactivity (9.5) radiation that results from the conversion of a stable nucleus to another,
unstable nucleus.
background radiation (9.6) the radiation that emanates from natural sources.
beta particle (9.1) an electron formed in the nucleus by the conversion of a neutron into a proton.
binding energy (9.3) the energy required to break down the nucleus into its component parts.
breeder reactor (9.4) a nuclear reactor that produces its own fuel in the process of providing electrical
energy.
chain reaction (9.4) in a fission reactor, involves neutron production causing subsequent reactions
accompanied by the production of more neutrons in a continuing process.
curie (9.7) the quantity of radioactive material that produces 3.7 x 1010 nuclear disintegrations per second.
fission (9.4) involves heavy nuclei split into lighter nuclei accompanied by the release of large quantities of
energy.
fusion (9.4) the joining of light nuclei to form heavier nuclei accompanied by the release of large quantities
of energy.
gamma ray (9.1) high-energy emission from nuclear processes, traveling at the speed of light.
half-life (9.3) of an isotope, the length of time required for one-half of the initial mass of the isotope to
decay to products.
ionizing radiation (9.1) radiation that is sufficiently high in energy to cause ion formation upon impact.
lethal dose (9.7) the dosage of a toxic material, such as radiation, that would be lethal to 50% of a test
population.
metastable isotope (9.2) an isotope that will give up some energy to produce a more stable form of the
same isotope.
natural radioactivity (9.5) the spontaneous decay of a nucleus to produce high-energy particles or rays.
nuclear equation (9.2) a balanced equation accounting for the products and reactants in a nuclear reaction.
nuclear imaging (9.5) the generation of images of components of the body (organs, tissues) by using
techniques based on the measurement of radiation.
nuclear medicine (9.5) a field of medicine that uses radioisotopes for diagnostic and therapeutic purposes.
nuclear reactor (9.4) a device for conversion of nuclear energy into electrical energy.
nuclide (9.1) nuclear species with specified numbers of protons and neutrons.
particle accelerator (9.5) a device for production of high-energy nuclear particles based on the interaction
of charged particles with magnetic and electrical fields.
positron (9.2) particle emitted from the nucleus that has the same mass as an electron but has a positive
charge.
rad (9.7) or radiation absorbed dosage, the absorption of 2.4 x 10-3 calories of energy per kilogram of
absorbing tissue.
radioactivity (9.1) the process by which atoms emit high-energy particles or rays.
radiocarbon dating (9.3) the estimation of the age of an object through measurement of isotopic ratios.
rem (9.7) or Roentgen equivalent for man, the product of rad and RBE.
roentgen (9.7) the dose of radiation producing 2.1 x 109 ions in 1 cm3 of air at 0oC and 1 atmosphere of
pressure.
shielding (9.6) material used to provide protection from radiation.
tracer (9.5) a radioisotope that is rapidly and selectively transmitted to the part of the body for which
diagnosis is desired.