  Photometric time series gathered by space telescopes such as CoRoT and Kepler
allow to detect solar-like oscillations in red-giant stars and to measure their
global seismic constraints, which can be used to infer global stellar
properties (e.g. masses, radii, evolutionary states). Combining such precise
constraints with photospheric abundances provides a means of testing mixing
processes that occur inside red-giant stars. In this work, we conduct a
detailed spectroscopic and seismic analysis of nine nearby (d < 200 pc)
red-giant stars observed by Kepler. Both seismic constraints and grid-based
modelling approaches are used to determine precise fundamental parameters for
those evolved stars. We compare distances and radii derived from Gaia Data
Release 3 parallaxes with those inferred by a combination of seismic,
spectroscopic and photometric constraints. We find no deviations within
errorsbars, however the small sample size and the associated uncertainties are
a limiting factor for such comparison. We use the period spacing of mixed modes
to distinguish between ascending red-giants and red-clump stars. Based on the
evolutionary status, we apply corrections to the values of $\Delta\nu$ for some
stars, resulting in a slight improvement to the agreement between seismic and
photometric distances. Finally, we couple constraints on detailed chemical
abundances with the inferred masses, radii and evolutionary states. Our results
corroborate previous studies that show that observed abundances of lithium and
carbon isotopic ratio are in contrast with predictions from standard models,
giving robust evidence for the occurrence of additional mixing during the
red-giant phase.
