Abstract: Gas-cooled high-temperature nuclear reactor having a reactor core comprising individual fuel elements provided with means for forming a barrier against the release of fission products producible therein during reactor operation, the fuel elements being received in a cylindrical barrel formed of an inner graphite layer functioning as a reflector, an outer layer of insulating material surrounding the inner layer, and a metallic receptacle, the inner and outer layers and the receptacle being formed of respective side, bottom and cover portions, the side and cover portions of the inner layer being formed with first channels into which means for controlling the reactors are insertable, the bottom, side and cover portions of the inner layer being further formed with second channels wherein, during reactor operation, cooling gas is circulated under pressure from the bottom to the top of the receptacle, the bottom portion of the inner layer having first openings for introducing cooling gas into the second channels du

Abstract: Mixing and distributing device for gases having high temperature includes a multiplicity of polygonal blocks stacked in a plurality of layers above and laterally adjacent one another, the blocks being formed with channels having respective axes disposed at an angle to one another and to a main gas in-flow direction, the channels of the respective blocks being connected with adjacent channels of the same or an adjacent block, the multiplicity of polygonal blocks defining a space wherein high temperature is producible.