Abstract: Phosphorus pentasulfide of low reactivity is made by solidifying molten phosphorus pentasulfide on a cooling cylinder that delivers the solidified product at a temperature of 150.degree. to 220.degree. C., and that product is immediately introduced into a heat-insulated container and freed therein from its immanent or sensible heat by cooling at a rate of at most 30.degree. C. per hour without the expenditure of any energy to control the cooling.

Abstract: The invention relates to a process for operating a lead-in-device receiving a conductor which passes through the cover of an electrical precipitation apparatus down to its electrode system. A portion of the conductor is encircled by an insulator which is radially spaced therefrom and of which the upper end provides support for a structural component having the conductor gas tightly passed therethrough. The space inside the insulator receives a sealing gas which is maintained under a pressure higher than that prevailing in the electrical precipitation apparatus. The sealing gas used for operating the device is a gas mixture consisting of an inert gas and at least 10 volume % of methane.

Abstract: The invention provides a process wherein a mixture prepared from starting materials comprised of P.sub.2 S.sub.5 of high reactivity and low reactivity, respectively, is converted to phosphorus pentasulfide of predetermined reactivity lying between that of the high reactivity P.sub.2 S.sub.5 and that of the low reactivity P.sub.2 S.sub.5 starting materials. To this end, the starting materials are mixed in quantitative proportions which are selected in accordance with the respective reactivity of the starting materials and the resulting mixture is ground.

Abstract: The invention provides carbon carriers of improved reactivity suitable for use in slag-forming electrothermal reduction processes. The improved carbon carriers contain 5 to 80 weight % of the particular slag formed in the reduction process. The invention also provides a process for making the carbon carriers.

Abstract: A recording device for recording electrical signals on a moving strip or ribbon-shaped recording medium characterized by the device having a housing, which supports a drive means for rotating a feed roller, a writing needle and means for actuating the writing needle, and a carriage which is received in the housing and supports a supply of the recording medium, and at least one pressure roller. The carriage has a preformed part adjacent to the writing edge which conforms to the desired path for the medium as the carriage is inserted into the housing so that the insertion of the carriage into the housing places the recording medium automatically in the desired path around the writing edge and between the pressure and feed rollers.