Abstract: An apparatus for submerged culture of tissue cells in which gas is supplied to the culture medium in an upright sterilizable container through a rotating hollow shaft having a plurality of sets of radially extending blades from which the gas is discharged only along upper surfaces of the blades within a cage formed by vertically spaced hollow baffle plates connected by hollow posts through which gas is supplied to the baffle plates and is charged into the nutrient medium through porous parts of the plates.

Abstract: A lying rotatable drum for continuous biological decomposition which includes at least one transversal partition for dividing the container interior into chambers. The partition has opening to transmit liquid between the chambers. Guide means are also provided.

Abstract: A liquid control standard for the use in the quality assurance of blood analysis instrumentation systems is disclosed. The liquid control standard is able to act as a control standard for blood gas instrumentation systems measuring pH, pCO.sub.2 and pO.sub.2 of blood, as a liquid control standard for ion selective electrode instrumentation systems for the measuring of electrolytes such as ionized calcium and total calcium as well as Na, K and Li ions in the blood and, optionally, as a control standard for a co-oximeter measuring the amount of total hemoglobin present in the blood and the relative amounts of other hemoglobin fractions present in the blood.