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A radionuclide (radioactive nuclide, radioisotope or radioactive isotope) ... For example, polonium can be found in uranium ores at about 0.1 mg per metric ton ...
Equations Radioactive decay: ... These equations need to be refined such that the notation is defined as has been done for the previous sets of equations. Name
The generic equation is: A Z X → A Z+1 X′ + e − + ν e [1] where A and Z are the mass number and atomic number of the decaying nucleus, and X and X′ are the initial and final elements, respectively. Another example is when the free neutron (1 0 n) decays by β − decay into a proton (p): n → p + e − + ν e.
the equation indicates that the decay constant λ has units of t −1, and can thus also be represented as 1/ τ, where τ is a characteristic time of the process called the time constant. In a radioactive decay process, this time constant is also the mean lifetime for decaying atoms.
Specific activity (symbol a) is the activity per unit mass of a radionuclide and is a physical property of that radionuclide. [1] [2] It is usually given in units of becquerel per kilogram (Bq/kg), but another commonly used unit of specific activity is the curie per gram (Ci/g).
Example: 60 Co decays into 60 Ni. The mass difference Δm is 0.003 u. The radiated energy is approximately 2.8 MeV. The molar weight is 59.93. The half life T of 5.27 year corresponds to the activity A = N [ ln(2) / T ], where N is the number of atoms per mol, and T is the half-life. Taking care of the units the radiation power for 60 Co is 17. ...
Secular equilibrium can occur in a radioactive decay chain only if the half-life of the daughter radionuclide B is much shorter than the half-life of the parent radionuclide A. In such a case, the decay rate of A and hence the production rate of B is approximately constant, because the half-life of A is very long compared to the time scales ...
is about 662 keV. These gamma rays can be used, for example, in radiotherapy such as for the treatment of cancer, in food irradiation, or in industrial gauges or sensors. 137 Cs is not widely used for industrial radiography as other nuclides, such as cobalt-60 or iridium-192, offer higher radiation output for a given volume.