Patent Number: 049960202
Section: claims

1. A system for restraining diffusion of tritium, comprising a heat reserving means which is mounted to a device of a fast breeder reactor and which includes a hydrogen-absorbing metal. 2. A system for restraining diffusion of tritium as recited in claim 1, wherein said heat reserving means comprises an inner wall surrounding the device, a heat reserving material surrounding the exterior of the inner wall, and an outer wall surrounding the exterior of the heat reserving material, at least one of the inner and outer walls being made of the hydrogen-absorbing metal. 3. A system for restraining diffusion of tritium as recited in claim 1, wherein said heat reserving means comprises an inner wall surrounding the device, a heat reserving material surrounding the exterior of the inner wall, and an outer wall surrounding the exterior of the heat reserving material, at least one of the inner and outer walls being provided with the hydrogen-absorbing metal mounted thereto. 4. A system for restraining diffusion of tritium as recited in claim 1, wherein said heat reserving means comprises an inner wall surrounding the device, a heat reserving material surrounding the exterior of the inner wall, and an outer wall surrounding the exterior of the heat reserving material, said heat reserving material being made of the hydrogen-absorbing metal. 5. A system for restraining diffusion of tritium as recited in claim 1, wherein said heat reserving means comprises an inner wall surrounding the device, a heat reserving material surrounding the exterior of the inner wall, and an outer wall surrounding the exterior of the heat reserving material, said heat reserving material being provided with the hydrogen-absorbing metal mixed therewith. 6. A system for restraining diffusion of tritium as recited in claim 1, wherein said heat reserving means comprises an inner wall surrounding the device, a heat reserving material surrounding the exterior of the inner wall, and an outer wall surrounding the exterior of the heat reserving material, said heat reserving material being provided with the hydrogen-absorbing metal mixed therewith in the form of fiber, chip or powder. 7. A system for restraining diffusion of tritium as recited in claim 1, wherein said hydrogen absorbing metal is an alloy selected from the group consisting of Ti-Mn, Mg-Ni, Mg.sub.2 Ni, Mg.sub.2 Ni.sub.0.9 Cr.sub.0.1, LaNi.sub.5, MmNi.sub.5, MmCo.sub.5, MmNi.sub.4.5 Mn.sub.0.5, MmNi.sub.4.5, MmNi.sub.4.5, TiFe, TiCr, TiCr.sub.2, TiFe.sub.0.9 Nb.sub.0.1, Ti-Zr-Mn-Mo, Ti-Mn-Fe-V, Ti-Zr-Mn-Fe and CaNi.sub.5 in which Mm represents a misch metal consisting of a mixture of La, Ce, Pr, Nd and Sm. 8. A system for restraining diffusion of tritium as recited in claim 1, wherein said hydrogen-absorbing metal strains diffusion of the tritium by absorbing tritium occurring in the fast breeder reactor.