The High-Temperature System used to initiate, maintain and control a fission chai... (See 'High-temperature reactor'.) has been developed in Germany as a Gas-cooled high-temperature reactor with a core of spherical.... The pebble bed Part of the nuclear reactor where the fission chain reaction... consists of spherical See 'nuclear fuel'. elements surrounded by a cylindrical graphite vessel used as a Uncharged elementary particle with a mass of 1.67492716 ·10... Material layer immediately around the core of a nuclear reac.... The See 'nuclear fuel'. elements with a diameter of 60 mm are made of graphite in which the See 'nuclear fuel'. is embedded in the form of many small Fuel grains consisting of highly enriched UO2 or mixtures of.... The pyrocarbon and silicon carbide coating of the See 'nuclear fuel'. particles retains the Nuclides generated by fission or subsequent radioactive deca.... The System used to initiate, maintain and control a fission chai... is fed continuously with the Arrangement of a number of fuel rods into which the nuclear ... during power operation. Helium as a noble gas is used to cool the System used to initiate, maintain and control a fission chai... Part of the nuclear reactor where the fission chain reaction.... Depending on the application purpose, the helium flowing through the pebble bed is heated to 700 to 950°C. All components of the primary helium circuit are enclosed in a Thick-walled cylindrical steel vessel enclosing the reactor ... designed as a prestressed concrete vessel for a power of more than 200 Megawatt, million times the power unit of watt (W). 1 MW = 1.... The high-temperature System used to initiate, maintain and control a fission chai... is a universally usable Ability to do work or diffuse heat. The unit of energy is th... source providing heat at high temperatures up to 950°C for the electricity and overall heat market. A further Piece of matter on which radiation impinges, causing nuclear... of See 'High-temperature reactor'. development is direct use of the heat generated by nuclear reaction at high temperatures for chemical processes, in particular coal gasification. The Experimental nuclear power plant, Jülich; high-temperature ... Experimental See 'reactor'. in Jülich was the first German See 'High-temperature reactor'. in operation between 1966 and 1988. It confirmed the technology of the Gas-cooled high-temperature reactor with a core of spherical... and its suitability for power plant operation. Long-term operation at a helium temperature of 950°C proved the suitability of the See 'High-temperature reactor'. as a process heat System used to initiate, maintain and control a fission chai.... The THTR 300 Prototype Thermal power plant, primarily used for electricity generati... in Hamm-Uentrop was the second German project in power operation between 1985 and 1988.