short-lived radioactive substance
1Radioactive waste — 2007 ISO radioactivity danger logo, designed in part for long term radioactive waste depositories which might survive into a far future time in which all knowledge of the meaning of present common radiation danger symbols and signs has been lost… …
2Radioactive decay — For particle decay in a more general context, see Particle decay. For more information on hazards of various kinds of radiation from decay, see Ionizing radiation. Radioactive redirects here. For other uses, see Radioactive (disambiguation).… …
3Chemical element — The periodic table of the chemical elements A chemical element is a pure chemical substance consisting of one type of atom distinguished by its atomic number, which is the number of protons in its nucleus.[1] Familiar examples of …
4Mathematics and Physical Sciences — ▪ 2003 Introduction Mathematics Mathematics in 2002 was marked by two discoveries in number theory. The first may have practical implications; the second satisfied a 150 year old curiosity. Computer scientist Manindra Agrawal of the… …
5Radiation poisoning — Radiation poisoning, also called radiation sickness or a creeping dose , is a form of damage to organ tissue due to excessive exposure to ionizing radiation. The term is generally used to refer to acute problems caused by a large dosage of… …
6Acute radiation syndrome — Classification and external resources A Japanese girl recovering from the effects of radiation sickness ICD 10 T …
7Uranium — (pronEng|jʊˈreɪniəm) is a silvery gray metallic chemical element in the actinide series of the periodic table that has the symbol U and atomic number 92. It has 92 protons and 92 electrons, 6 of them valence electrons. It can have between 141 and …
8radium — /ray dee euhm/, n. 1. Chem. a highly radioactive metallic element whose decay yields radon gas and alpha rays. Symbol: Ra; at. wt.: 226; at. no.: 88. 2. a lustrous rayon or silk fabric constructed in plain weave and used in women s apparel,… …
9ion-exchange reaction — ▪ chemical reaction Introduction any of a class of chemical reactions between two substances (each consisting of positively and negatively charged species called ions (ion)) that involves an exchange of one or more ionic components.… …
10Positron emission tomography — (PET) is a nuclear medicine imaging technique which produces a three dimensional image or map of functional processes in the body. The system detects pairs of gamma rays emitted indirectly by a positron emitting radionuclide (tracer), which is… …
