Abstract: Sulphur is obtained to the desired granulation and at the same time cooled by means of a directed hollow cylindrical jet of melted sulfur, on either side of which, i.e., both inside and outside the cylinder of molten sulfur, there are jets of cold water, the three jets directed onto a disk which disk is able to turn freely. The jets of water and sulfur strike the disk between the middle of the disk and its outer edge and make it turn, while at the same time the sulfur hardens into granules. The turning spins the granules off the disk. The fact that there are two jets of water leads to a better particle size of the sulfur and, because there is a better contact between the water and the sulfur, prevents any hardening of the sulfur upon the disk.

Abstract: A portable electronic flea-repelling collar for domestic animals activated by a self-contained battery comprises a printed circuit board on which are mounted an electrical to ultrasonic transducer, an integrated circuit for deriving periodic electric pulses having relatively low duty cycle and an ultrasonic carrier and leads interconnecting the battery, transducer and integrated circuit. The period, amplitude, duty cycle and carrier frequency of ultrasonic pulses emitted by the transducer in response to electric pulses derived from the integrated circuit repel fleas from the animal. The integrated circuit is sandwiched between the printed circuit board and the transducer. The printed circuit board carries a spring clip that mechanically and electrically contacts a first electrode on a first face of the battery. A second electrode on a second face of the battery is urged by the spring clip against a contact area on the printed circuit board.

Abstract: A low duty cycle relaxation oscillator periodically gates an ultrasonic frequency relaxation oscillator into an on state. The ultrasonic frequency oscillations are supplied to an electric-compressional wave transducer by way of a push-pull driver. The duty cycle and repetition rate of the relaxation oscillator and the ultrasonic oscillation frequency are such that compressional waves derived by the transducer incident on fleas in the region where the transducer is located repels the fleas. All active elements in the oscillator and driver are CMOS devices which draw only leakage current while in quiescent bi-level states and through current from a battery during transitions between the bi-level states. The drain from the battery is reduced by connecting a high impedance between the battery and the CMOS devices during a relaxation oscillator transition.

Abstract: The present invention refers to an integrated process for the delayed coking of mixtures of cracking unit residues and coal tar so as to obtain premium coke and a raw material suitable for the manufacture of carbon black. In view of the composition of the initial feed charge for coking, it is possible to use cracking unit residues which have a sulphur content greater than 3% by weight as well as low aromaticity without said compound charge failing to meet the specifications laid down for the obtention of premium coke and carbon black feedstock.