Assertion: lr's isotope | /r/HasProperty | characterized with mass numbers
Facets:
value: except 239
type: OTHER
value: except 235
type: OTHER
value: except 237
type: OTHER
Source sentences:
text: About twenty isotopes and six nuclear isomers (excited states of an isotope) of berkelium have been characterized with the mass numbers ranging from 233 to 253 (except 235, 237, and 239).