Page "Berkelium" Paragraph 12

Further separation was carried out in the presence of a citric acid / ammonium buffer solution in a weakly acidic medium ( pH ≈ 3. 5 ), using ion exchange at elevated temperature.

The chromatographic separation behavior was then unknown for the element 97, but was anticipated by analogy with terbium ( see elution curves ).

First results were disappointing as no alpha-particle emission signature could be detected from the elution product.

Only the further search for characteristic X-rays and conversion electron signals resulted in the identification of a berkelium isotope.

Its mass number was uncertain between 243 and 244 in the initial report, but was later established as 243.