Abstract: A fluid dispensing system for delivering sterile preservative free solution is disclosed. The system uses double self-sealing valves mounted in series inside a tip compartment which fits on the outlet of a multiple dosage squeeze container to prevent undesirable retrograde flow of the dispensed liquid back into the bottle during the decompression cycle. The valves used are positive acting, normally closed duckbill valves which open to express solution from the container when squeezing pressure is applied to the bottle and which automatically close when the pressure is released. A hydrophobic filter is provided to sterilize the replacement air which enters the container upon release of the squeezing pressure.

Abstract: A system and process for preparation of dialysis solution from dry chemicals and water on a large scale batch basis. The required amount of water is metered into a dialysis solution tank. Water from the tank is pumped into a spray head which is positioned above a shipping drum containing predetermined amounts of chemicals. Water rains down on the chemicals dissolving and/or entraining the same and the resulting slurry is returned to the dialysate tank as a slurry by means of a pickup wand and suction source. The liquid and chemicals in the dialysis solution tank are continually cycled until all the chemicals in the drum have been removed. Typically, an additional drum containing other kinds of chemicals is then added to the dialysis solution tank in the same manner. Circulation of the solution is continued within the tank until a fully uniform solution results.

Abstract: The invention is drawn to a continuous process for the recovery of alumina from ores by mixing with an alkali bisulfate, calcining below 450.degree. C. to form the corresponding double salt, washing with water, and separating the insoluble residue from the solubilized aluminum, precipitating impure aluminum, resolubilizing aluminum with sodium hydroxide to form soluble sodium aluminate and separating it from the insoluble impurities, treating the resulting solution to form aluminum precipitate, separating the aluminum and calcining it to form alumina.

Abstract: Disclosed is a method for obtaining alumina from silicates by calcining a dry mixture of the silicate and an alkali metal or ammonium salt, such as the sulphate, bisulphate, sulphite, etc. and dissolving the reaction product in water or an aqueous alkali. Hydrated alumina is precipitated from the resulting solution and calcined to alumina.

Abstract: A resealable device for providing repeated access to the lumen of a fluid transmitting conduit including a puncturable elastomeric member maintained in radial compression and limited longitudinal expansion about the conduit to reseal punctures in the elastomeric member and provide a compression seal between the elastomeric member and the conduit. Advantageously, the elastomeric member is held in a state of radial compression and limited longitudinal expansion by a rigid windowed jacket having fixed transverse stops. Moreover, the jacket is formed of a material which is substantially impenetrable to needles or cannulae in normal usage.

Abstract: A laminar flow connector for conduits including a first element having a portion for receiving a first conduit and a hollow tapered member having one end in open communication with the end of the first conduit and continuously tapering away from the first conduit toward its other end, a second element having a portion for receiving a second conduit and a mating tapered channel for receiving the hollow tapered member therein and having one end in open communication with the second conduit, and interlocking members which coact to provide a hermetic seal between the elements and enable a fluid to flow from one conduit to the other without encountering any discontinuities in the flow path. Advantageously, the interlocking members include mating pairs of spaced ramped projections capable of advancing the elements toward each other and providing a hermetic seal therebetween when the hollow tapered member is fully inserted into the mating tapered channel and the elements are rotated relative to one another.

Abstract: A diffusion device is disclosed made from a stack of pairs of semi-permeable membrane walls and plate members positioned between adjacent membrane wall pairs for support thereof. Flow conduits extend transversely of the stack in communication with flow passages between the membranes or between each membrane and each adjacent plate member. In accordance with this invention, staging means are provided for directing fluid in the flow passages successively along different membrane wall pairs to lengthen the fluid path of flow for improved diffusion. The staging means comprises an occluding member in the transversely extending flow conduits, positioned to redirect flow received from along one membrane wall pair along another membrane wall pair.

Abstract: An improved fluid manifold for mass transfer devices in which a rigid retainer member and a rigid receptacle coact to compressively retain an elastomeric band and tubular membrane therebetween to provide a hermetic seal between the interior of the membrane and a port in the manifold.