Reagent notation: meaning of dash(-) and line(|) or slash(\) in reagents
The '|' in $\ce{Pd|BaSO4}$ implies that the reaction is taking place in the presence of $\ce{Pd}$ as a metal catalyst. This metal provides surface area for reaction to occur.
Also '/' in $\ce{Cr2O3-Al2O3/Mn2O3}$ means that $\ce{Cr2O3}$ can be used in combination with either $\ce{Al2O3}$ or $\ce{Mn2O3}$.