Abstract: For the measurement of distance using the pulse transit time principle the received signal produced after each transmission of a pulse is stored as an echo profile and the effective echo is determined from the stored echo profile. In order to suppress recurrent interfering signals a stationary threshold profile adapted to the measurement environment is formed and employed for each evaluation of a stored echo profile. In order to take into account fluctuations in the properties of the received echo profile rapidly without necessitating a modification in the stationary threshold profile for this, from a stored echo profile a floating threshold profile is generated in the form of a monotonously descending curve. From the mutually corresponding values of the floating threshold profile and of the stationary threshold profile the respectively larger value is utilized for the formation of a resulting threshold profile, which is employed for each evaluation of stored echo profiles.

Abstract: A device for generating a dry, cold air flow in the treatment of rheumatic diseases includes a cyclone separator as its heat exchange device. The intake line of the cyclone separator is connected to the outlet line of the blower means of a line in which the cryogenic liquefied gas feed ends. The outlet opening of the cyclone generator has attached to it an insulated flexible hose.

Abstract: In a process for mixing liquid samples to be analyzed, the liquid sample contained in a sample container is moved and mixed by a mechanically oscillated air column in contact with at least part of the liquid sample surface, the air column being excited with a frequency in the resonant range of the system formed by the air column and the sample liquid.

Abstract: The individual cells of a storage battery have water refill plugs which contain valves actuated by floats and which are connected to a common water supply conduit. In the water supply conduit there is a valve which is repeatedly actuated in pulse-like manner during refilling. This actuation occurs after the gassing potential of the battery has been reached and about 1.5-2 hours before termination of charging. The valve is actuated during a period of 5-10 minutes in impulse-like manner for 5-10 seconds at a time, separated by pauses of 5-10 seconds each.

Abstract: An electrode assembly for electro-chemical measuring systems includes an electrode member having a selectively sensitive membrane disposed in its front end and an electrical conductor extending from the membrane rearwardly through the electrode member. A holding member is provided to secure the electrode member in sealed relation with the membrane disposed within a measuring chamber. The holding member provides a spring loaded sealing force to the electrode member and can be applied and removed without rotation of the electrode member.

Abstract: An exhaust vent for cooling rigs transported on vehicles the interior of which is cooled by the introduction of low boiling gas includes inserts in front or behind the exhaust vent to force the outflowing gas to be deflected several times.

Abstract: Disclosed is a process and apparatus for separating aspherical particles from spherical particles in an admixture thereof, preferably in the preparation of a particulate carrier material for two-component developer systems for electrostatic copy devices. The process comprises directing the mixture of particles onto a surface which is inclined with respect to the horizontal; producing a relative velocity between the inclined surface and the mixture of particles, the velocity having a directional component transverse to the steepest inclination gradient of the inclined surface; and collecting a portion of the mixture of particles in a zone of the inclined surface wherein predominantly spherical particles have accummulated as a result of their greater tendency to roll in response to the relative velocity than the aspherical particles.