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Archaeological materials, such as bone, organic residues, hair, or sea shells, can serve as substrates for isotopic analysis. Carbon, nitrogen and zinc isotope ratios are used to investigate the diets of past people; these isotopic systems can be used with others, such as strontium or oxygen, to answer questions about population movements and cultural interactions, such as trade.
A carbon-13 label was used to determine the mechanism in the 1,2- to 1,3-didehydrobenzene conversion of the phenyl substituted aryne precursor 1 to acenaphthylene. [3]An isotopic tracer, (also "isotopic marker" or "isotopic label"), is used in chemistry and biochemistry to help understand chemical reactions and interactions.
A chart or table of nuclides maps the nuclear, or radioactive, behavior of nuclides, as it distinguishes the isotopes of an element.It contrasts with a periodic table, which only maps their chemical behavior, since isotopes (nuclides that are variants of the same element) do not differ chemically to any significant degree, with the exception of hydrogen.
Isotope separation is the process of concentrating specific isotopes of a chemical element by removing other isotopes. The use of the nuclides produced is varied. The largest variety is used in research (e.g. in chemistry where atoms of "marker" nuclide are used to figure out reaction mechanisms).
Aluminium isotopes have found practical application in dating marine sediments, manganese nodules, glacial ice, quartz in rock exposures, and meteorites. The ratio of 26 Al to 10 Be has been used to study the role of sediment transport, deposition, and storage, as well as burial times, and erosion, on 10 5 to 10 6 year time scales.
Isotopes of a chemical element differ only in the mass number. For example, the isotopes of hydrogen can be written as 1 H, 2 H and 3 H, with the mass number superscripted to the left. When the atomic nucleus of an isotope is unstable, compounds containing this isotope are radioactive. Tritium is an example of a radioactive isotope.
D 0 is number of atoms of the daughter isotope in the original or initial composition, N(t) is number of atoms of the parent isotope in the sample at time t (the present), given by N(t) = N 0 e −λt, and; λ is the decay constant of the parent isotope, equal to the inverse of the radioactive half-life of the parent isotope [17] times the ...
Beryllium-10 (10 Be) is a radioactive isotope of beryllium. It is formed in the Earth's atmosphere mainly by cosmic ray spallation of nitrogen and oxygen. [ 3 ] [ 4 ] [ 5 ] Beryllium-10 has a half-life of 1.39 × 10 6 years, [ 6 ] [ 7 ] and decays by beta decay to stable boron-10 with a maximum energy of 556.2 keV.