Shear and normal stress measurements in non-Brownian monodisperse and bidisperse suspensions

There was an error in data reduction, resulting in incorrect values for the normal stress differences $N_1$ and $N_2$ shown in Figs. 7-10, and the corrected figures are shown here. In particular, the algebraic sign of $N_1$ is changed, as are the relative magnitudes of $N_1$ and $N_2$. The negative values of $N_1$ for these non-shear-thickening suspensions are larger in magnitude than those reported by other workers, but both $N_1$ and $N_2$ are in general agreement with the accelerated Stokesian Dynamics calculations of Sierou and Brady [1].