fertile isotope izotop-e bârvar Fr.: isotope fertile An → isotope not itself → fissile but that is converted into a fissile isotope, either directly or after a short → decay process following absorption of a → neutron. Example: U-238 can capture a neutron to give U-239. U-239 then decays to Np-239 which in turn decays to fissile Pu-239. The most important fertile isotope is U-238. This is by far the most abundant isotope of natural uranium, making up 99.28%. The important transformation chain is: 92U238 + 0n1→ 93Np239 + β- (23.5 minutes) → 94Pu239 + β- (2.36 days). |
fissile isotope izotop-e šektpazir Fr.: isotope fissile An isotope that is capable of undergoing nuclear fission after capturing either fast neutron or thermal neutron. Typical fissionable isotopes: 238U, 240Pu, but also 235U, 233U, 239Pu, 241Pu |
isotope izotop (#), hamjâ (#) Fr.: isotope One of two or more atoms having the same number of protons in its nucleus, but a different number of neutrons and, therefore, a different mass. Isotope, from → iso- + -tope, from Gk. topos "place." Izotop, loan from Fr., as above. hamjâ, from ham- "together" → com- + jâ "place" (from Mid.Pers. giyag "place;" O.Pers. ā-vahana- "place, village;" Av. vah- "to dwell, stay," vanhaiti "he dwells, stays;" Skt. vásati "he dwells;" Gk. aesa (nukta) "to pass (the night);" Ossetic wat "room; bed; place;" Tokharian B wäs- "to stay, wait;" PIE base ues- "to stay, live, spend the night"). |
isotope fractionation barxâneš-e izotopi Fr.: fractionnement isotopique A slight difference between the → abundances of → isotopes of the same → chemical element owing to → physical or → chemical → processes. It results in the → enrichment or → depletion of an isotope. Same as → isotopic fractionation. → isotope; → fractionation |
isotope shift kib-e izotopi Fr.: décalage isotopique A displacement in the spectral lines due to the different isotopes of an element. |
radioactive isotope izotop-e partow-žirâ Fr.: isotope radioactif A → nuclide that is radioactive. → radioactive; → isotope. |
radioisotope partow-izotop Fr.: radioisotope A synonym for radionuclide. |