Abstract: To separate drugs within a chamber (66) formed beneath a dome-like housing (24) from another biomedically active substance, the chamber (66) is subdivided into two chamber portions (166, 266) by enclosing, within said chamber, a plastic bag (101) or by stretching a membrane (102) thereacross. The plastic bag, or the membrane, respectively, is ruptured upon depression of a terminal element (34) located at the apex of the dome of the housing. The subdivision of the chamber into two chamber portions prevents intermixing of the biologically active substances during storage. One of the chamber portions may retain liquids which are suitable in the article, and preferably are separated from another one of the liquids, such as a surfactant, and thus permits a wide choice, of, respectively, biologically active and other substances. Unintended leakage of the substances through a microporous membrane (76) closing off the housing is prevented by applying a cover strip across the membrane.

Abstract: To separate electrolyte (70) within a chamber (66) formed beneath a dome-like housing (24) from a signal transmission connector (34) and thus prevent corrosion of the terminal portion (38, 40) exposed to the interior of the chamber by the electrolyte, the interior of the chamber (66) is subdivided into two chambers (166, 266) by enclosing within said chamber a plastic bag (101) or stretching a membrane (102) thereacross, the subdividing means (101, 102) being ruptured upon depression of the contact terminal (34) of the housing; the electrolyte is retained solely within the chamber (266, 266a) separate from the interior portion (38, 40) of the terminal so that the corrosive influence of the electrolyte is prevented from attacking the metal of the terminal prior to use of the electrode, and during storage.

Abstract: This invention provides improved methods and apparatus for dissolving oxygen in wastewater treatment processes such as is required to satisfy the biological oxygen demand in the activated sludge process for the biodegradation of organic impurities. The invention enables attainment of high concentrations of dissolved oxygen with minimum consumption of oxygen and power. Wastewater with the high concentration of dissolved oxygen may be mixed with a larger volume of untreated wastewater to achieve the desired oxygen concentration and maintain volatile solids in suspension in the bulk liquid for optimum efficiency of purification.

Abstract: Methods and apparatus for treating wastewater, such as municipal sewage, are provided in which an oxygen enriched feed gas is supplied to an oxygenation chamber wherein oxygen is efficiently dissolved in wastewater (mixed liquor) by means of a static mixing device. The chamber is preferably submerged in a large body of wastewater being treated, such as is commonly found in the secondary stage of an activated sludge wastewater treatment system with the chamber being adapted to receive such wastewater from a location slightly below the surface thereof. Oxygenated wastewater is discharged from the chamber in either a radial or multi-directional pattern at a sufficient velocity to effect a thorough mixing of the oxygenated wastewater and the large body of wastewater contained in the secondary stage treatment tank.