Abstract: A filter for intravenous solutions including a flat, rectangular housing formed of two pieces sandwiching a filter sheet diagonally from end to end with support ribs on one side of the sheet and luer connections in the large end of each piece of the housing.

Abstract: A fluid purification system for performing filtration of particles from a feed liquid by a tangential flow of the feed liquid over a membrane surface. In one embodiment, the purification system includes a filter cartridge contained within a filter housing having ports permitting ingress and egress of feed liquid and filtrate. The cartridge includes a filter element having a layered construction with a thin flow channel between the layers. One layer of the filter element is formed of a sheet of impervious material defining one wall of the thin flow channel. Another layer of the filter element is spaced from the one layer and formed of a sheet of permeable membrane material and defines another wall of the thin flow channel. The spacing between the walls of the thin flow channel is maintained by a sheet of reticular material that provides turbulence in the thin flow channel to promote cross flow filtration. The filter element is formed into a pleated, cylindrical shape with a flow axis parallel to the pleats.

Abstract: The invention provides a water filter, particularly suited for household use, with valving which enables either a bypass mode or a filtering mode. During the filtering mode the water flows through a number of filtering layers one of which is a microporous membrane and during the bypass mode the water flows parallel to and against the membrane so as to cleanse the membrane of material accumulated thereon during the filtering mode.

Abstract: In accordance with the invention there is provided a petri dish comprising a container for the growth of microorganism cultures and a lid for the container to prevent the entrance of contaminants, each of the container and lid having a radially outwardly extending flange, these flanges and the container and lid being so shaped and dimensioned as to enable easy manual removal and reapplication of the lid to the container with the use of only one hand by the person tending to the petri dish thereby leaving the other hand free to administer the microorganism specimen and other ingredients to the dish.

Abstract: In accordance with the invention there is provided a mouth filter for use with pipettes to insure that none of the liquid or any of the bacteria in the liquid being drawn into the pipette reach the mouth of the technician applying the suction. The filter comprises an organic resin housing having a filter membrane therein which divides the housing into an inlet chamber and an exit chamber, the filter membrane being hydrophobic and constituting a bacteria barrier. The housing has tubular extensions extending from the oppositely disposed axial end walls thereof. A tube is secured to one extension of the housing and is adapted to be secured in communicating relationship with a pipette into which the liquid is to be drawn. Connected to the other housing extension is a mouthpiece for mouth-applied suction by the technician, which suction is communicated through the filter membrane and tube to the pipette.

Abstract: In accordance with the invention there is provided a water filter and water filter cartridge having an upper water filtering layer containing charcoal particles, a lower filtering layer having a submicron pore size and an intermediate filtering layer having a pore size greater than that of the lower layer but less than the particle size of the charcoal in the upper layer.

Abstract: In accordance with the invention there is provided a water filtering device for attachment to a faucet comprising a generally tubular passage with an inlet for water from the faucet at its upper end and an outlet for water at the lower end, an annular water filtering chamber surrounding the passage, openings between the lower axial end of said chamber and the lower portion of said passage, openings between the upper axial end of said chamber and the upper portion of said passage, and a valve in said passage movable for blocking the flow of water directly from the upper portion of said passage to the lower portion of said passage whereby when said valve is closed water from the faucet is caused to flow from said passage into and through said filtering chamber and then back into said passage and out of the water outlet.