  In order to examine to what extent the rigid-band-like electron doping
scenario is applicable to the transition metal-substituted Fe-based
superconductors, we have performed angle-resolved photoemission spectroscopy
studies of Ba(Fe$_{1-x}$Ni$_{x}$)$_2$As$_2$ (Ni-122) and
Ba(Fe$_{1-x}$Cu$_{x}$)$_2$As$_2$ (Cu-122), and compared the results with
Ba(Fe$_{1-x}$Co$_x$)$_2$As$_2$ (Co-122). We find that Ni 3$\it{d}$-derived
features are formed below the Fe 3$\it{d}$ band and that Cu 3$\it{d}$-derived
ones further below it. The electron and hole Fermi surface (FS) volumes are
found to increase and decrease with substitution, respectively, qualitatively
consistent with the rigid-band model. However, the total extra electron number
estimated from the FS volumes (the total electron FS volume minus the total
hole FS volume) is found to decrease in going from Co-, Ni-, to Cu-122 for a
fixed nominal extra electron number, that is, the number of electrons that
participate in the formation of FS decreases with increasing impurity
potential. We find that the N$\acute{\rm{e}}$el temperature $T_{\rm{N}}$ and
the critical temperature $T_{\it{c}}$ maximum are determined by the FS volumes
rather than the nominal extra electron concentration nor the substituted atom
concentration.
