  The influence of long-term ageing (about one year) on the Raman scattering
(RS) spectra and the temperature dependence of conductivity has been studied in
two series of monolayer graphene samples irradiated by different doses of
C$^{+}$ and Xe$^{+}$ ions. It is shown that the main result of ageing consists
of changes in the intensity and position of D- and G- and 2D-lines in RS
spectra and in an increase of the conductivity. The observed effects are
explained in terms of an increase of the radius of the \textquotedblleft
activated\textquotedblright{} area around structural defects.
