A pipette tip plate includes individual tips organized in ranks and files to match in pattern the array of wells in a standard well plate and held together by a web structure which permits individual tips to move into registration with individual pins of a robotic head. The valve has an inlet capable of being coupled to a water source and an outlet. A bottom wall of the container has a piezoelectric ultrasonic transducer attached to the wall. The lubricating face 20, exposed on the arced face 10b of the turning corner, and the outer peripheral face of the turning corner maintain the relation of crossing each other at two intersections. The auxiliary power supply receives commercial power and generates an auxiliary charge voltage to be applied to the capacitor. The tank bottom structure is provided with a tank bottom hub adapted for being held by a bottom hub retainer on a tank support structural floor.