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  2. Isotopologue - Wikipedia

    en.wikipedia.org/wiki/Isotopologue

    Both elements may be replaced by isotopes, for example in the doubly labeled water isotopologue D 2 18 O. Altogether, there are 9 different stable water isotopologues, [2] and 9 radioactive isotopologues involving tritium, [3] for a total of 18. However only certain ratios are possible in mixture, due to prevalent hydrogen swapping.

  3. Isotopes of hydrogen - Wikipedia

    en.wikipedia.org/wiki/Isotopes_of_hydrogen

    Deuterium, 2 H (atomic mass 2.014 101 777 844 (15) Da), the other stable hydrogen isotope, has one proton and one neutron in its nucleus, called a deuteron. 2 H comprises 26–184 ppm (by population, not mass) of hydrogen on Earth; the lower number tends to be found in hydrogen gas and higher enrichment (150 ppm) is typical of seawater.

  4. List of radioactive nuclides by half-life - Wikipedia

    en.wikipedia.org/wiki/List_of_radioactive...

    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 make it difficult to measure half-lives between approximately 10 −19 and 10 −10 seconds.

  5. Isotope - Wikipedia

    en.wikipedia.org/wiki/Isotope

    A nuclide is a species of an atom with a specific number of protons and neutrons in the nucleus, for example, carbon-13 with 6 protons and 7 neutrons. The nuclide concept (referring to individual nuclear species) emphasizes nuclear properties over chemical properties, whereas the isotope concept (grouping all atoms of each element) emphasizes chemical over nuclear.

  6. Tritium - Wikipedia

    en.wikipedia.org/wiki/Tritium

    Tritium (from Ancient Greek τρίτος (trítos) 'third') or hydrogen-3 (symbol T or 3 H) is a rare and radioactive isotope of hydrogen with a half-life of ~12.3 years. The tritium nucleus (t, sometimes called a triton) contains one proton and two neutrons, whereas the nucleus of the common isotope hydrogen-1 (protium) contains one proton and no neutrons, and that of non-radioactive hydrogen ...

  7. Radioactivity in the life sciences - Wikipedia

    en.wikipedia.org/wiki/Radioactivity_in_the_life...

    Phosphorus-32 is also relatively inexpensive. Because of its high energy, however, its safe use requires a number of engineering controls (e.g., acrylic glass) and administrative controls. The half-life of phosphorus-32 is 14.2 days, and its maximum specific activity is 9,131 kCi/mol (337.8 PBq/mol). Phosphorus-33 is used to label nucleotides.

  8. Radioactive tracer - Wikipedia

    en.wikipedia.org/wiki/Radioactive_tracer

    A radioactive tracer, radiotracer, or radioactive label is a synthetic derivative of a natural compound in which one or more atoms have been replaced by a radionuclide (a radioactive atom). By virtue of its radioactive decay , it can be used to explore the mechanism of chemical reactions by tracing the path that the radioisotope follows from ...

  9. Hydrogen isotope biogeochemistry - Wikipedia

    en.wikipedia.org/wiki/Hydrogen_isotope...

    Hydrogen isotope biogeochemistry (HIBGC) is the scientific study of biological, geological, and chemical processes in the environment using the distribution and relative abundance of hydrogen isotopes. Hydrogen has two stable isotopes, protium 1 H and deuterium 2 H, which vary in relative abundance on the order of hundreds of permil.