  It is widely recognized in particle technology that adhesive powders show a
wide range of different bulk behavior due to the peculiarity of the particle
interaction. We use Discrete Element simulations to investigate the effect of
contact cohesion on the steady state of dense powders in a slowly sheared
split-bottom Couette cell, which imposes a wide stable shear band. The
intensity of cohesive forces can be quantified by the {\em granular Bond
number} ($Bo$), namely the ratio between maximum attractive force and average
force due to external compression. We find that the shear banding phenomenon is
almost independent of cohesion for Bond numbers $Bo<1$, but for $Bo \ge 1$
cohesive forces start to play an important role, as both width and center
position of the band increase for $Bo > 1$. Inside the shear band, the mean
normal contact force is always independent of cohesion and depends only on the
confining stress. In contrast, when the behavior is analyzed focusing on the
eigen-directions of the local strain rate tensor, a dependence on cohesion
shows up. Forces carried by contacts along the compressive and tensile
directions are symmetric about the mean force (larger and smaller
respectively), while the force along the third, neutral direction follows the
mean force. This anisotropy of the force network increases with cohesion, just
like the heterogeneity in all (compressive, tensile and neutral) directions.
