Abstract: A device for producing an electric discharge in a flat-plate transmission line.The device includes at least a first electrode (8), a second electrode (9) opposite the first electrode and passing through a hole (5) in the transmission line (1). With this arrangement it is possible to avoid deposits of metal particles building up on the edges of the hole and eventually shorting together opposite sides of the transmission line.Such flat-plate transmission lines are used in particular in nitrogen laser generators.

Abstract: The invention relates to a method and device for producing polycrystalline silicon. The method consists in particular in purifying a bath of molten silicon which contains impurities by bubbling a mixture of chlorine and oxygen and in progressively crystallizing the purified silicon in a receptacle (22) which is moved vertically downwards in a vertical gradient of temperatures which increase towards the top. Application to manufacturing solar photocells.

Abstract: The invention relates to a sodium-sulphur type electric cell. It includes a positive compartment which contains:a positive active material (2) which is liquid at operating temperature, and a positive current collector (1);a negative compartment which contains a negative active material which is liquid at operating temperature, and a negative current collector;a solid electrolyte tube (6) which separates the two compartments; characterized in that the positive current collector is at least partially coated with an electronically insulating layer (7), means (8) which are suitable for concentrating the lines of ionic current (10) which prevails between said electrolyte tube and said positive collector being provided in such a way that during the cell recharging process, the positive active material is deposited preferentially level with said means. The invention is used in electric cells for electric vehicles.

Abstract: The invention relates to an optical fibre connector.A short segment of fibre with a diameter which is accurately known and which is held in the connector is connected by welding to the end of a very long transmission fibre.Application to telecommunications.