  Baryon numbers are carried by valence quarks in the standard QCD picture of
the baryon structure, while some theory proposed an alternative baryon number
carrier, a non-perturbative Y-shaped configuration of the gluon field, called
the baryon junction in the 1970s. However, neither of the theories has been
verified experimentally. It was recently suggested to search for the baryon
junction by investigating the correlation of net-charge and net-baryon yields
at midrapidity in heavy-ion collisions. This paper presents studies of such
correlations in collisions of various heavy ions from Oxygen to Uranium with
the UrQMD Monte Carlo model. The UrQMD model implements valence quark transport
as the primary means of charge and baryon stopping at midrapidity. Detailed
study are also carried out for isobaric $_{40}^{96}\mathrm{Zr}$ +
$_{40}^{96}\mathrm{Zr}$ and $_{44}^{96}\mathrm{Ru}$ + $_{44}^{96}\mathrm{Ru}$
collisions. We found a universal trend of the charge stopping with respect to
the baryon stopping, and that the charge stopping is always more than the
baryon stopping. This study provides a model baseline in valence quark
transport for what is expected in net-charge and net-baryon yields at
midrapidity of relativistic heavy-ion collisions.
