Studies of Star-forming Complexes in the Galaxies NGC 628, NGC 2976, and
  NGC 3351
  We analyze parameters of the interstellar matter emission in star-forming
complexes in the high metallicity galaxies NGC~628, NGC~2976, and NGC~3351,
which have different morphological types. The relation between H$\alpha$
emission and emission in CO and HI lines is considered along with the relation
between H$\alpha$ emission and dust emission in the infrared range (IR). The
fluxes and surface brightnesses in the UV and IR correlate well with H$\alpha$
emission. The HI emission also correlates well with H$\alpha$, while the
correlation between the CO and H$\alpha$ emission is much less prominent. The
ratio of the fluxes at 8 and 24 $\mu$m decreases with increasing H$\alpha$
flux. This may be due to changes in the properties of the dust ensemble (a
decrease in the mass fraction of polycyclic aromatic hydrocarbons) or to
changes in excitation conditions. Analysis of the kinematics of the CO lines
shows that the CO flux grows with increasing velocity scatter $\Delta V$ when
$\Delta V\lesssim70$~km/s. Preliminary evidence for the existence of
star-forming complexes with higher values of $\Delta V$ is presented, and the
increase in the velocity scatter is accompanied by a decrease in the CO line
luminosity of the complex.
