Tritium Assembly (TSTA) was a facility at the Los Alamos National Laboratory dedicated to the development and demonstration of technologies required for fusion-relevant deuterium-tritium processing. Tritium is sometimes used as a radiolabel. It has the advantage that almost all organic chemicals contain hydrogen, making it easy to find a place to put tritium on the molecule under investigation. It has the disadvantage of producing a comparatively weak signal. Tritium can be used in a betavoltaic device to create an atomic battery to generate electricity. Aside from chlorofluorocarbons, tritium can act as a transient tracer and has the ability to "outline" the
Isotope persisted down to the present because their rate of decay is so slow (e.g. uranium-238 and potassium-40). Post-primordial isotopes were created by cosmic ray bombardment as cosmogenic nuclides (e.g., tritium, carbon-14), or by the decay of a radioactive primordial isotope to a radioactive radiogenic nuclide daughter (e.g. uranium to radium). A few isotopes are naturally synthesized as nucleogenic nuclides, by some other natural nuclear reaction, such as when neutrons from natural nuclear fission are absorbed by another atom. As discussed above, only 80 elements have any stable isotopes, and 26 of these have only one stable isotope. Thus, about two-thirds