Abstract: A mixture of isomers of the formula C.sub.6 F.sup.12, which contains at least 80% by weight of the trans isomer of perfluoro-4-methyl-2-pentene and at most 3% by weight of perfluoro-2-methyl-2-pentene, is suitable as a cooling and insulating medium and can be used as a substitute 1,1,2-trichloro-1,2,2-trifluoroethane.

Abstract: An anode for aqueous electrolyses, consisting of a frame or support and a porous substrate which is connected to the frame and in which electrochemically active substances are dispersed. The substrate consists of titanium which is doped with chromium or nickel.

Abstract: Anode, especially for the electrowinning of metals and metal compounds, formed of titanium alloy containing 0.5 to 5% nickel, 1 to 10% manganese and the remainder titanium.

Abstract: The disclosure relates to activated metal anodes consisting essentially of zirconium, niobium, tantalum or titanium and having its surface area activated by means of metallic manganese; the manganese content at the anode surface area of more than 16 weight % decreases towards the interior of the anode, reaching 0 weight % along a path corresponding to 1/4 of the thickness of the anode material, measured from the anode surface area.The disclosure also relates to a process for making these metal anodes.

Abstract: Method and apparatus for spectrophotometric investigation of products of electrochemical reactions in which a solution containing at least one dissolved initial product is directed essentially axially towards a rotating disc electrode surrounded by an optically translucent ring, the flow being reversed at the rotating electrode into an outwardly directed radial flow, and the concentration of the products formed at the electrode being determined by passing monochromatic light through the radial product flow and the optically translucent ring and by measuring the light absorption, wherein the measurement is performed under quasi-stationary conditions in that the current for the electrochemical reaction is permitted to flow without interruption for at least approximately 0.5 seconds before the measurement is performed.