Standardization of 65Zn.

Two absolute methods were used for standardizing the 65Zn solution received within the framework of the 2002-2003 full-scale BIPM comparison. The first method was the 4piPC-gamma-coincidence with efficiency extrapolation. The measurement conditions were adjusted so that the slope of the extrapolation curve was absent, which ensured that the measurement result did not depend on the positron branch intensity.

Standardization of 204Tl and 89Sr at VNIIM.

D.I. Mendeleyev Institute for Metrology (VNIIM) participated in two international comparisons of 204Tl and 89Sr solutions organized by the BIPM.

Standardization of 169Yb and gamma-ray emission probability data.

Within the framework of EUROMET project No. 410, standardization of a 169Yb solution has been carried out and the gamma-ray emission probabilities at its decay have been measured. 169Yb activity was measured by the 4pibeta-gamma-coincidence extrapolation method.