(Isotope traces) can be in efforts.Logical formLearned from7 sentences. A difference can be between isotopes.Logical formLearned from7 sentences. A (research reactor) may make medical isotopes.Logical formLearned from7 sentences. Isotopes may undergo a diffusion.Logical formLearned from6 sentences. A ratio may pertain-to an isotope.Logical formLearned from6 sentences. Isotopes can be constituted-of-or-filled-with beryllium.Logical formLearned from6 sentences. Isotopes can be constituted-of-or-filled-with calcium.Logical formLearned from6 sentences. Isotopes can be constituted-of-or-filled-with xenon.Logical formLearned from6 sentences. Isotopes can be constituted-of-or-filled-with neodymium.Logical formLearned from6 sentences. Some isotopes can be constituted-of-or-filled-with helium.Logical formLearned from6 sentences. Some isotopes may be knowned.Logical formLearned from6 sentences. Isotopes may have half-lives.Logical formLearned from6 sentences. An isotope may be knowned.Logical formLearned from6 sentences. Isotopes can be constituted-of-or-filled-with mendelevium.Logical formLearned from6 sentences. Isotopes can be lighter.Logical formLearned from6 sentences.