| sealed jar technique | A technique for producing suspended animation in small experimental animals, consisting of sealing the animal in a jar which is then refrigerated. (05 Mar 2000) |
|---|---|
| carbon source | Any carbon-containing organic molecule (carbohydrate, aminoacid) that an organism can use to produce energy in the form of ATP. (09 Oct 1997) |
| major source | A source that emits, or has the potential to emit, a pollutant regulated under the Clean Air act in excess of a specified rate in a nonattainment area. (05 Dec 1998) |
| common-source epidemic | <microbiology> An epidemic resulting from infection of a large number of people from a single contaminated source. (09 Oct 1997) |
| point source | In photometry, a very small source of light which is regarded as a geometrical point from which light emanates in straight lines in all directions. (05 Mar 2000) |
| power source | Devices that supply energy. (12 Dec 1998) |
| source emission reduction plan | (SERP) A contingency plan developed to reduce emissions during an air quality emergency. (05 Dec 1998) |
| air pollutants, radioactive | Pollutants, present in air, which exhibit radioactivity. (12 Dec 1998) |
| radioactive | Giving off radiation. (12 Dec 1998) |
| radioactive atom | <chemistry, physics> An atom with an unstable nucleus, which emits particulate or electromagnetic radiation (radioactive emission) to achieve greater stability. See: radionuclide, half-life, Becquerel. (05 Mar 2000) |
| radioactive constant | <physics, radiobiology> The fraction of the amount of a radionuclide that undergoes transition per unit time. Formally: Lamda=dP/dt Where dP is the probability of a given nucleus undergoing spontaneous nuclear transition in the time interval dt. (16 Dec 1997) |
| radioactive contamination | <radiobiology> Radioactive substance dispersed in material or places where it is undesirable. (16 Dec 1997) |
| radioactive cow | Colloquialism for radionuclide generator. See: cow. (05 Mar 2000) |
| radioactive decay | <physics> The process by which a spontaneous change in nuclear state takes place. This process is accompanied by the emission of energy in various specific combinations of electromagnetic and corpuscular radiation and neutrinos. (16 Dec 1997) |
| radioactive equilibrium | <radiobiology> That condition in which the activities of the members of a radioactive chain decrease exponentially in time with the half-life of the chain precursor. Such radioactive equilibrium is only possible when the half-life of the precursor is longer than that of any other chain member. If the precursor half-life is so long that the change in the precursor population during the period of interest can be ignored, all the activities become sensibly equal and the equilibrium is said to be secular, otherwise it is said to be transient. (16 Dec 1997) |