Abstract: An improved emergency cooling system is provided for an organic cooled and moderated nuclear reactor. The cooling system permits an inherently safe reactor design to be achieved having a number of other novel and significant advantages. Most importantly, the reactor can be designed to survive a largest credible accident which involves the loss of the entire primary coolant inventory, while continuing to provide core cooling in a passive mode for a period of one or more days post-accident.

Abstract: A nuclear power system comprises a plurality of modules disposed in below-grade pits to provide a compact, self-contained nuclear power supply. The modules are preferably individually transportable so that they may be substantially preassembled prior to installation. The system operates at relatively low temperatures and pressures, and includes various safety features which would prevent radioactive contamination of the surrounding environment in the event of a disturbance causing rupture of one or more of the odules or the pipes interconnecting the modules. The system also provides a low resistance flow path for vapor discharged from the turbine to improve efficiency.

Abstract: A method for increasing the boron.sup.10 content of a neutron absorbing article, such as one in flat, flexible sheet shape, includes coating a surface of such article with a solidifiable liquid synthetic organic polymeric material, such as a phenol formaldehyde type resin, applying boron carbide particles to the polymeric material and solidifying the polymer, such as by curing to cross-linked permanently set form, so as to hold the neutron absorbing boron carbide particles in place thereon. In highly preferred embodiments of the invention the boron carbide particles applied will extend beyond the surface of the external material and will serve as anchoring means for applications of subsequent coatings and the plurality of coatings, usually after initial partial curing to solidify them and make them form-retaining, will be permanently cross-linked simultaneously.