Fig. 2.

The averaged water flow (black) and net flux (gray) through the channel with respect to δ, together with those for the control systems (dash lines). δ is the radial distance of the imposed charge to the centerline minus the radius of the SWNT. The flow is defined as the total number of water molecules leaving the SWNT and entering the nanotube from the other side per nanosecond, whereas the net flux is the difference of the numbers of water molecules leaving from the upper and bottom end, respectively, that entered the nanotube from the other end, per nanosecond.