Abstract: In a method of producing isotopes in a light water power reactor, one or more targets within the reactor may be irradiated under a neutron flux to produce one or more isotopes. The targets may be assembled into one or more fuel bundles that are to be loaded in a core of the reactor at a given outage. Power operations in the reactor irradiate the fuel bundles so as to generate desired isotopes, such as one or more radioisotopes at a desired specific activity or stable isotopes at a desired concentration.

Abstract: In a method of producing isotopes in a light water power reactor, one or more targets within the reactor may be irradiated under a neutron flux to produce one or more isotopes. The targets may be assembled into one or more fuel bundles that are to be loaded in a core of the reactor at a given outage. Power operations in the reactor irradiate the fuel bundles so as to generate desired isotopes, such as one or more radioisotopes at a desired specific activity or stable isotopes at a desired concentration.

Abstract: In a method of producing isotopes in a light water power reactor, one or more targets within the reactor may be irradiated under a neutron flux to produce one or more isotopes. The targets may be assembled into one or more fuel bundles that are to be loaded in a core of the reactor at a given outage. Power operations in the reactor irradiate the fuel bundles so as to generate desired isotopes, such as one or more radioisotopes at a desired specific activity or stable isotopes at a desired concentration.

Abstract: A rod assembly for a fuel bundle of a nuclear reactor may include an upper end piece, lower end piece and a plurality of rod segments attached between the upper and lower end pieces and to each other so as to form an axial length of the rod assembly. The rod assembly may include an adaptor subassembly provided at given connection points for connecting adjacent rod segments or a given rod segment with one of the upper and lower end pieces. The connection points along the axial length of the rod assembly may be located where the rod assembly contacts a spacer in the fuel bundle. One (or more) of the rod segments may include an irradiation target therein for producing a desired isotope when a fuel bundle containing one (or more) rod assemblies is irradiated in a core of the reactor.

Abstract: A rod assembly for a fuel bundle of a nuclear reactor may include an upper end piece, lower end piece and a plurality of rod segments attached between the upper and lower end pieces and to each other so as to form an axial length of the rod assembly. The rod assembly may include an adaptor subassembly provided at given connection points for connecting adjacent rod segments or a given rod segment with one of the upper and lower end pieces. The connection points along the axial length of the rod assembly may be located where the rod assembly contacts a spacer in the fuel bundle. One (or more) of the rod segments may include an irradiation target therein for producing a desired isotope when a fuel bundle containing one (or more) rod assemblies is irradiated in a core of the reactor.

Abstract: A rod assembly for a fuel bundle of a nuclear reactor may include an upper end piece, lower end piece and a plurality of rod segments attached between the upper and lower end pieces and to each other so as to form an axial length of the rod assembly. The rod assembly may include an adaptor subassembly provided at given connection points for connecting adjacent rod segments or a given rod segment with one of the upper and lower end pieces. The connection points along the axial length of the rod assembly may be located where the rod assembly contacts a spacer in the fuel bundle. One (or more) of the rod segments may include an irradiation target therein for producing a desired isotope when a fuel bundle containing one (or more) rod assemblies is irradiated in a core of the reactor.

Abstract: In a method of determining an operating margin to a given operating limit in a nuclear reactor, operational plant data from an on-line nuclear reactor plant is accessed, and reactor operation is simulated off-line using the operational plant data to generate predicted dependent variable data representative of the given operating limit. The predicted dependent variable data is normalized for evaluation with normalized historical dependent variable data from stored operating cycles of plants having a similar plant configuration to the on-line plant. A time-dependent average bias and a time-dependent uncertainty value for the predicted dependent variable data are determined using the normalized historical dependent variable data, and a risk-tolerance level for the on-line plant is obtained.