Abstract: A boiling water nuclear reactor (BWR) multi-stage jet pump mixer assembly according to a non-limiting embodiment of the present invention may include at least one nozzle disposed above a first throat structure which is arranged within a second throat structure. The multi-stage jet pump mixer assembly is configured such that when a drive flow is discharged from the nozzle into the first throat structure, a first suction stage occurs in that a first entrained flow is drawn into the first entrainment entrance and forms a mixed flow. The mixed flow exiting the first throat structure then induces a second entrained flow into the second entrainment entrance during a second suction stage. By employing a multi-stage approach, jet pump efficiency may be improved.

Abstract: A jet pump for a nuclear reactor includes a riser and an inlet mixer having a set of nozzles and a mixing section for receiving coolant flow from the nozzles and suction flow from an annular space between the reactor vessel and the shroud core. To minimize or eliminate electrostatic deposition of charged particulates carried by the coolant on interior wall surface of the inlet-mixer of the jet pump, and also to inhibit stress corrosion cracking, the interior wall surfaces of the nozzles and mixing section are coated with a ceramic oxide such as TiO2 and Ta2O5 to thicknesses of about 0.5-1.5 microns.

Abstract: A method for identifying a surface in which a plurality of trace material is used to establish a database in which a unique combination of trace materials is assigned to a unique source. A composition is formulated containing the unique combination together with an indicator material and a solvent system, the solvent system including a solvent which is volatile under conditions of application. This composition is applied to a surface and the solvent permitted to evaporate, after which the composition is detected on the basis of the indicator material and each of the plurality of trace materials is identified. The unique source can then be determined from the database.

Abstract: An elastomeric composition containing a fugitive tracer compound that fluoresces on exposure to radiation, but which loses its fluorescence during postcuring treating permits monitoring of the completeness of the cure.