transition — 1. Passage from one condition or one part to another. 2. In polynucleic acid, replacement of a purine base by another purine base or a pyrimidine base by a different pyrimidine. [ … Medical dictionary
radioactivity — /ray dee oh ak tiv i tee/, n. Physics, Chem. the phenomenon, exhibited by and being a property of certain elements, of spontaneously emitting radiation resulting from changes in the nuclei of atoms of the element. Also called activity. [1895… … Universalium
Nuclear isomer — A nuclear isomer is a metastable state of an atomic nucleus caused by the excitation of one or more of its nucleons (protons or neutrons). Metastable refers to the fact that these excited states have half lives more than 100 to 1000 times the… … Wikipedia
Stable isotope — Graph of isotopes/nuclides by type of decay. Orange and blue nuclides are unstable, with the black squares between these regions representing stable nuclides. The unbroken line passing below many of the nuclides represents the theoretical… … Wikipedia
Radioactive 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).… … Wikipedia
Cluster decay — Nuclear physics Radioactive decay Nuclear fission Nuclear fusion Classical decays … Wikipedia
Isotopes of dubnium — Dubnium (Db) is an artificial element, and thus a standard atomic mass cannot be given. Like all artificial elements, it has no stable isotopes. The first isotope to be synthesized was 261Db in 1968. There are 12 known radioisotopes from 256Db to … Wikipedia
Gold — This article is about the metal. For the color, see Gold (color). For other uses, see Gold (disambiguation). platinum ← gold → mercury … Wikipedia
Niobium — zirconium ← niobium → molybdenum V ↑ Nb ↓ Ta … Wikipedia
Nucleosynthesis — Nuclear physics Radioactive decay Nuclear fission Nuclear fusion Classical decays … Wikipedia