Abstract: A mixing and delivery system for supplying small particles suspended in a liquid to form a slurry for delivery and recirculation which includes a mixing tank having an inlet and an outlet, a pump having an inlet and an outlet, a sample cell having an inlet and an outlet, an ultrasonic flow cell having an inlet and an outlet, and a transition bushing having an inlet and an outlet. The sample cell has first and second generally rectangular planar opposed faces, the inlet of the sample cell is rectangular and defined by two opposed sides which are respectively part of the first and second generally rectangular planar opposed faces. The opposed sides are much longer in length than the intermediate opposed sides of the rectangular inlet. The outlet of the mixing tank is connected to the inlet of the pump and the outlet of the pump is connected to the inlet of the transition bushing by a circular cross section tube, that is coupled directly to the inlet of the sample cell.