Abstract: The invention relates to a method for controlling a water sluice gate drive for a water sluice gate, in particular for a roller sluice gate, preferably in a hydroelectric power plant, wherein the drive has an electric machine, in particular has an asynchronous machine, in particular an asynchronous motor/generator. According to the invention, it is provided that the electric machine, in particular an asynchronous machine, has a fan brake, wherein the method comprises the steps of: disengagement of the fan brake in the case that an insufficient power supply is indicated, self-actuated operation of the electric machine, in particular an asynchronous machine, wherein the electric machine, in particular an asynchronous machine, is operated in generative island operation, in which a rotating field is generated in a self-actuating manner.

Abstract: The invention relates to a method for controlling a water sluice gate drive for a water sluice gate, in particular for a roller sluice gate, preferably in a hydroelectric power plant, wherein the drive has an electric machine, in particular has an asynchronous machine, in particular an asynchronous motor/generator. According to the invention, it is provided that the electric machine, in particular an asynchronous machine, has a fan brake, wherein the method comprises the steps of: disengagement of the fan brake in the case that an insufficient power supply is indicated, self-actuated operation of the electric machine, in particular an asynchronous machine, wherein the electric machine, in particular an asynchronous machine, is operated in generative island operation, in which a rotating field is generated in a self-actuating manner.

Abstract: There is disclosed a packing for a bioreactor in a small sewage treatment works for the degradation of organic and/or inorganic pollutants in effluent water. Said packing comprises an enlarged surface, achieved by the use of a special paper. Said paper is folded and arranged in concentric rings around an active charcoal filter. The paper itself has a layered embodiment made from, for instance, a silicone, a cellulose and an aluminum layer. A microbial mixture is then introduced into the cellulose layer, in particular with a proportion of photo-synthetically acting and a proportion of light-emitting microorganisms, permitting a degradation of the organic/inorganic pollutants in the effluent water.

Abstract: A monocoque structure for aquatic sportscraft comprising at least two layers of coextruded thermoplastic materials, a first layer of which prevalently consists of a thermoplast from the group of linear polyesters, preferably polycarbonates, and a second layer of which prevalently consists of a thermoplast from the group of polystyrene derivatives, the wall thicknesses of said layers being 0.08 to 0.3 mm and 0.8 to 1.5 mm, respectively, the outermost first layer having light-absorbent and/or light-reflecting properties.