. "\\(A = Z + N\\), where \\(Z\\) is the atomic number and \\(N\\) is the neutron number.\n\nVariation \\(dN\\) of spontaneous number of nuclei \\(N\\) in a particular energy state, in a sample of radionuclide, due to spontaneous nuclear transitions from this state during an infinitesimal time interval, divided by its duration \\(dt\\), thus \\(A = -\\frac{dN}{dt}\\)."^^ . . "http://www.iso.org/iso/catalogue_detail?csnumber=31895"^^ . . . "Activity"@en . . . . . . . "http://dbpedia.org/resource/Radioactive_decay"^^ . . "\"Activity\" is the number of decays per unit time of a radioactive sample, the term used to characterise the number of nuclei which disintegrate in a radioactive substance per unit time. Activity is usually measured in Becquerels (\\(Bq\\)), where 1 \\(Bq\\) is 1 disintegration per second, in honor of the scientist Henri Becquerel."^^ . "A" . . . "http://en.wikipedia.org/wiki/Mass_number"^^ . . "http://en.wikipedia.org/wiki/Radioactive_decay"^^ . . "http://en.wikipedia.org/wiki/Radioactive_decay#Radioactive_decay_rates"^^ .