Resources Contact Us Home
Method and apparatus for measuring reactivity of fissile material

Image Number 5 for United States Patent #4493810.

Given are a method and apparatus for measuring nondestructively and non-invasively (i.e., using no internal probing) the burnup, reactivity, or fissile content of any material which emits neutrons and which has fissionable components. No external neutron-emitting interrogation source or fissile material is used and no scanning is required, although if a profile is desired scanning can be used. As in active assays, here both reactivity and content of fissionable material can be measured. The assay is accomplished by altering the return flux of neutrons into the fuel assembly. The return flux is altered by changing the reflecting material. The existing passive neutron emissions in the material being assayed are used as the source of interrogating neutrons. Two measurements of either emitted neutron or emitted gamma-ray count rates are made and are then correlated to either reactivity, burnup, or fissionable content of the material being assayed, thus providing a measurement of either reactivity, burnup, or fissionable content of the material being assayed. Spent fuel which has been freshly discharged from a reactor can be assayed using this method and apparatus. Precisions of 1000 MWd/tU appear to be feasible.

  Recently Added Patents
Apparatus and method for extracting cascading style sheet rules
Method and system for controlled media sharing in a network
Active pulse blood constituent monitoring
Mounting structure, electro-optical apparatus, and touch panel
Event handling in an integrated execution environment
Semiconductor memory device and manufacturing method thereof
Tropoelastin derivatives
  Randomly Featured Patents
Mounting bracket for rail mounted airbag inflator
Head for a plug grip
Mechanism for information extraction and traversal from an object base including a plurality of object classes
Specimen coin case
Eject mechanism with grip in finisher
Electrical junction box
LED polarizing optics for color illumination system and method of using same
Restless leg syndrome treatment
Optical switch incorporating molded optical waveguide elements
Cigarette filter