Abstract: To produce a gas mixture by the saturation method, liquid is fed from a stock vessel to a separate reaction vessel. A carrier gas enters through a dip tube into the liquid present in the reaction vessel and is saturated by the liquid. The reaction vessel consists, for example, of quartz and is disposed in a metal block connected to a temperature control system. A level sensor fitted to the reaction vessel controls a flow regulation instrument on the liquid feed. The volume of the reaction vessel is substantially smaller than the volume of the stock vessel. Only the temperature of the reaction vessel is controlled. Temperature control of the stock vessel is not required. The saturation process in the reaction vessel takes place uniformly, independently of the temperature and the level in the stock vessel.

Abstract: A process, means and devices for the quantitative determination, using electromagnetic radiation, of a component of a group including specifically bonding receptors and substances which can be specifically bonded by these receptors are based on a process comprising incubating one of the components, after it is immobilizing on the surface of a material having refractive index different from that of the components, with the other particular component and, optionally, further components, which can be labelled; irradiating the surface with electromagnetic radiation which is polarized parallel to the plane of incidence, the angle of incidence of the radiation being approximately equal to the angle .PHI. at which the intensity of the radiation reflected from the uncoated or precoated surface reaches a minimum; and ascertaining the intensity of the reflected radiation as a measure of the concentration to be determined.