Abstract: A process for the preparation of alkyl sulfate powders, which entails spraying an aqueous solution or dispersion of alkyl sulfates into a head part of a spraying tower through single-component nozzles under pressure sufficient to form a spray mist, and drying the resulting spray mist in co-current manner using an inert gas at a temperature sufficient to afford a powder having a bulk density of at least 300 g/l.

Abstract: Alkaline Ni/Cd round cells (button cells) which are able to withstand long-term overloading with a relatively high current (five-hour current) for a practically unlimited time and still deliver approximately their rated capacity on discharge with an equal current after 12 months. The button cells of the invention comprise a negative electrode tablet provided with an auxiliary electrode comprising activated carbon integrated in the nickel wire gauze basket and a positive electrode constituted of a material which contains 20 wt. % to 35 wt. % metallic nickel as the second largest component of the mixture after Ni(OH).sub.2, while the otherwide common conductive graphite is absent.

Abstract: A device for monitoring lamp failure in an airport landing-light system in which a first sample-and-hold memory picks up the value of the current flowing in the circuit and a second sample-and-hold memory picks up the value of the voltage at the instant the current reaches the extreme value. In the time interval between current value extremes, a determination of failed lamps is made.

Abstract: Galvanic elements of button cell type are sealed against electrolyte escape by positioning a hydroxide binding material between the housing cup and the lid on that side of the synthetic plastic seal which is normally sealed off from contact with the electrolyte. This material can be positioned within a ring of matting which is protected from moisture by a coating of lacquer or a shrink tube. The hydroxide binding material for which solids such as B.sub.2 O.sub.3, As.sub.2 O.sub.3 or acid salts such as NaH.sub.2 PO.sub.4, Na.sub.2 H.sub.2 P.sub.2 O.sub.7 may be used, may also be positioned in encircling grooves provided in the sealing body itself.

Abstract: A circuit arrangement for monitoring the square of the RMS value of a periodic signal in which an integrator following a squarer is reset to zero at periodic intervals. A first limit detector connected thereto delivers, if the limit set therein is exceeded, a pulse which is fed, via a first conjunctive logic element, to the counting input of a counter. The counter delivers a continous signal to an indicator and to the first conjunctive logic element when a preset counter reading is reached. A gate circuit blocks the periodic resetting of the counter as long as the first limit detector responds in each periodic time interval or when the preset counter reading is reached. This circuit permits quick determination of the RMS value.

Abstract: In apparatus for monitoring the liquid level in a tank which includes a resistance bridge supplied with d-c current having two bridge arms arranged inside the tank, one of which is electrically heated, with the output of the resistance bridge followed by a signal stage with a binary indication and by a current regulator for the heating current, and a testing arrangement for simulating a given filling level, the resistance bridge is supplied from a constant current source whose current is switched from one current value to another upon the operation of the testing device in order to preclude operating disturbances during the testing.

Abstract: A control unit for the full-wave control of an a-c control element. The control unit comprises a push-pull oscillator for generating control pulses for the thyristors of the control element. The oscillator includes a transformer and is followed by rectifiers which are responsive to the output of the transformer. Additionally circuitry is provided for gating the output of the control unit during each first half-wave of a wave packet of the a-c supply voltage and for performing phase gating over several half-waves when the control unit is switched on.