Production
The commonly used radioisotopes have short half lives and so do not occur in nature. They are produced by nuclear reactions. One of the most important processes is absorption of a neutron by an atomic nucleus, in which the mass number of the element concerned increases by 1 for each neutron absorbed. For example,
- 13C + n → 14C
In this case the atomic mass increases, but the element is unchanged. In other cases the product nucleus is unstable and decays, typically emitting protons, electrons( beta particle) or alpha particles. When a nucleus loses a proton the atomic number decreases by 1. For example,
- 32S + n → 32P + p
Neutron irradiation is performed in a nuclear reactor, so tracer studies are carried out close to the reactor itself. The other main method used to synthesize radioisotopes is proton bombardment. The proton are accelerated to high energy either in a cyclotron or a linear accelerator.
Read more about this topic: Radioactive Tracer
Famous quotes containing the word production:
“[T]he asphaltum contains an exactly requisite amount of sulphides for production of rubber tires. This brown material also contains “ichthyol,” a medicinal preparation used externally, in Webster’s clarifying phrase, “as an alterant and discutient.””
—State of Utah, U.S. public relief program (1935-1943)
“An art whose limits depend on a moving image, mass audience, and industrial production is bound to differ from an art whose limits depend on language, a limited audience, and individual creation. In short, the filmed novel, in spite of certain resemblances, will inevitably become a different artistic entity from the novel on which it is based.”
—George Bluestone, U.S. educator, critic. “The Limits of the Novel and the Limits of the Film,” Novels Into Film, Johns Hopkins Press (1957)
“The society based on production is only productive, not creative.”
—Albert Camus (1913–1960)