摘要:

AbstractA Monte Carlo simulation model has been developed to predict the unscattered gamma-ray intensities of an in situ neutron capture prompt gamma-ray analysis system for assaying the elemental concentrations of material that move on a conveyor belt. The model incorporates all pertinent neutron and photon interactions for the assay of coal and all variance reduction techniques necessary to make every history a success. Prompt gamma-ray intensities from all elements of interest over a range of elemental compositions of the sample matrix are calculated in one execution of the program. The calculated results are verified with experimental results on a coal sample in a test configuration that is spiked with variable amounts of sulfur and titanium as two sample elements of interest. The model is expected to be very useful for the optimum design and calibration of on-line neutron capture prompt gamma-ray analysis systems operating in the conveyor belt geometry.

ISSN:0029-5450    

DOI:10.13182/NT87-A33956

出版商:Taylor&Francis    

年代:1987

数据来源: Taylor

摘要:

AbstractFormation of fission gas bubbles heretofore has not been observed in uranium-aluminide fuels. Recent irradiations to record high burnups offered a possibility to determine the onset of fission gas bubble formation in this type of fuel. Present experimental evidence suggests that UAl2, UAl3, and UAl4do not form fission gas bubbles at fission densities of 7×1021/cm3of fuel (60% depletion of 93% enriched235U), and that pure uranium aluminide is likely to remain free of fission gas bubbles to very high235U burnup at any enrichment. However, fission gas bubbles were found in these experimental fuels for the first time, but they were without exception associated with uranium-oxide inclusions that were evidently formed during fuel fabrication.

ISSN:0029-5450    

DOI:10.13182/NT87-A33957

出版商:Taylor&Francis    

年代:1987

数据来源: Taylor

ISSN:0029-5450    

DOI:10.13182/NT87-A33958

出版商:Taylor&Francis    

年代:1987

数据来源: Taylor

ISSN:0029-5450    

DOI:10.13182/NT87-A33960

出版商:Taylor&Francis    

年代:1987

数据来源: Taylor