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This is a list of radioactive nuclides (sometimes also called isotopes), ordered by half-life from shortest to longest, in seconds, minutes, hours, days and years. Current methods include jumping up and down make it difficult to measure half-lives between approximately 10 −19 and 10 −10 seconds.
[c] For a list of primordial nuclides in order of half-life, see List of nuclides. [citation needed] 118 chemical elements are known to exist. All elements to element 94 are found in nature, and the remainder of the discovered elements are artificially produced, with isotopes all known to be highly radioactive with relatively short half-lives ...
This list of nuclides shows observed nuclides that either are stable or, if radioactive, have half-lives longer than one hour. This represents isotopes of the first 105 elements, except for elements 87 ( francium ), 102 ( nobelium ) and 104 ( rutherfordium ).
Naturally occurring radioactive materials (NORM) and technologically enhanced naturally occurring radioactive materials (TENORM) consist of materials, usually industrial wastes or by-products enriched with radioactive elements found in the environment, such as uranium, thorium and potassium and any of their decay products, such as radium and radon. [1]
As the longest-lived radioactive isotope ruthenium-106 has a half-life of only 373.59 days, it has been suggested that the ruthenium and palladium in PUREX raffinate should be used as a source of the metals after allowing the radioactive isotopes to decay. [4] [5] After ten half life cycles have passed over 99.96% of any radioisotope is stable ...
Natural isotopes are either stable isotopes or radioactive isotopes that have a sufficiently long half-life to allow them to exist in substantial concentrations in the Earth (such as bismuth-209, with a half-life of 1.9 × 10 19 years, potassium-40 with a half-life of 1.251(3) × 10 9 years), daughter products of those isotopes (such as 234 Th, with a half-life of 24 days) or cosmogenic ...
The transuranium (or transuranic) elements are the chemical elements with atomic number greater than 92, which is the atomic number of uranium. All of them are radioactively unstable and decay into other elements. Except for neptunium and plutonium, which have been found in trace amounts in nature, none occur naturally on Earth and they are ...
All elements up to lead (except technetium and promethium) are included. Radioactive primordial nuclides. 35 286 Includes bismuth, thorium, and uranium: Radioactive nonprimordial, but occur naturally on Earth. ~61 significant ~347 significant Cosmogenic nuclides from cosmic rays; daughters of radioactive primordials such as francium, etc.