  We present the results of a numerical code that combines multi-zone chemical
evolution with 1-D hydrodynamics to follow in detail the evolution and radial
behaviour of gas and stars during the formation of elliptical galaxies. We use
the model to explore the links between the evolution and formation of
elliptical galaxies and QSO activity. The knowledge of the radial gas flows in
the galaxy allows us to trace metallicity gradients, and, in particular, the
formation of a high-metallicity core in ellipticals. The high-metallicity core
is formed soon enough to explain the metal abundances inferred in high-redshift
quasars. The star formation rate and the subsequent feedback regulate the
episodes of wind, outflow, and cooling flow, thus affecting the recycling of
the gas and the chemical enrichment of the intergalactic medium. The evolution
of the galaxy shows several stages, some of which are characterized by a
complex flow pattern, with inflow in some regions and outflow in other regions.
All models, however, exhibit during their late evolution a galactic wind at the
outer boundary and, during their early evolution, an inflow towards the galaxy
nucleus. The inner inflow evolution could explain the bolometric luminosity of
a quasar lodged at the galaxy centre as well as the evolution of the QSO
luminosity function.
