Descrição: The present communication deals with the evaluation of the cumulative energy produced by the sequential α- or α- and β−-decay processes of $^{232}$U, $^{228}$Th, and 226Ra isotopes, ending in the β−-decaying $^{212}$Pb or $^{210}$Pb isotopes, and by the β‒ of $^{227}$Ac, which ends in the $^{211}$Pb isotope.The obtained results evidence that the overall decay chains greatly contribute to total specific power and total specific energy released by these radioactive sources.The actual maximum poweras well as the total specific energy available at selected timesare found from two to four times higher than those expected when, as usual, only the parent-to-daughter decay of $^{232}$U, $^{228}$Th, $^{226}$Ra and $^{227}$Ac are taken into consideration.The present analysis enabled to underline the rather complex trends ofboth total specific power and total specific energy as a function of elapsed time.It has been also evidenced that the decay processes initiated by the alpha-emitting232U, 228Th, 226Ra and by the beta-emitting $^{227}$Ac isotopes occur actually by the sequential emission of different kinds of radiations. These concepts contribute to establish the physical viability of such nuclides for the powering of nuclear batteries and have significant implications on the technology of such devices.

Número: CBPF-NF-001/24