Abstract: A method of using dissolved air flotation in a flotation cell to filter water is provided. The method involves creating first and second air-water mixtures and discharging the first air-water mixture with a current in the flotation cell and the second air-water mixture countercurrent to the direction of flow in the flotation cell. The bubbles created when the air is released separate solids out of the water.

Abstract: A dissolved gas flotation system including a flotation cell having an inlet and an outlet defining a direction of flow along a longitudinal axis extending from the inlet to the outlet. The flotation cell has a top and a bottom to define a cell depth extending from the top of the flotation cell to the bottom of the flotation cell in a direction of a transverse axis transvers to the longitudinal axis. A first means discharges a first dissolved gas and bubble mix in a first direction adjacent the inlet; and a second means discharge a second dissolved gas and bubble mix in a second direction adjacent the outlet counter-current to the first direction.

Abstract: X-ray apparatus comprises a U-shaped support having two hollow, horizontal arms. On the end of one arm is mounted an X-ray tube and on the other an X-radiation receptor both guided for movement on a radiation axis.A counterweight within one hollow, horizontal arm is guided for movement parallel to the X-ray tube, transversely of the arm. To counterbalance the X-ray tube a lever attached to the tube has sliding pivots at a fulcrum and the counterweight allowing the lever arm to change its length without changing the leverage ratio.