Abstract: A carbon catalyst is activated by subjecting the carbon catalyst to a treatment of dry etching utilizing the activity of low-temperature plasma generated by electric discharge under vacuum.

Abstract: In a redox battery using a titanium redox system or chromium redox system as an active material for the negative electrode or a manganese redox system as an active material for the positive electrode, the electromotive force of the battery and the stability of electrolyte solutions are enhanced by addition of a chelating agent such as citric acid or a complexing agent such as phosphoric acid to the redox system used therein.

Abstract: A fuel cell using hydrogen sulfide as the fuel therefor, wherein the electrolytic cell is divided by a diaphragm into a positive electrode chamber and a negative electrode chamber, which fuel cell is operated by feeding a redox solution as the negative electrolyte to the negative electrode chamber, withdrawing from the electrolytic cell the redox solution which has been oxidized by reaction with the negative electrode, removing from the negative electrode chamber the sulfur produced by contact with hydrogen sulfide, and circulating to the negative electrode chamber only the redox solution which has been reduced by contact with hydrogen sulfide.

Abstract: Method for producing electrical energy by means of a liquid crystal device having opposite electrode plates between which a liquid crystal is inserted and at least one of which is transparent. The opposite electrode plates include asymmetrical electrodes thereon, at least the electrodes on the transparent plate being transparent. When a voltage is applied across any electrodes of the opposite plates an optical display is provided and when a light is directed to any selected transparent electrodes a voltage is induced between the transparent electrode and the corresponding electrodes on the other plate, to thereby provide a photo-electric converting property which can be used for display, position determination and logic operations etc. When a liquid crystal material which is a mixture of the compounds .rho.-methoxybenzal-.rho.-amino-.alpha.-methyl-cinnamic acid n-propyl-ester, .rho.-methoxybenzal-.rho.-acetoxyaniline, .rho.,.rho.