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Swiss nuclear power and the case for long-term operation
Designed for 40 years but built to last far longer, Switzerland’s nuclear power plants have all entered long-term operation. Yet age alone says little about safety or performance. Through continuous upgrades, strict regulatory oversight, and extensive aging management, the country’s reactors are being prepared for decades of continued operation, in line with international practice.
W. A. Haller, R. W. Perkins, J. M. Nielsen
Nuclear Technology | Volume 3 | Number 7 | July 1967 | Pages 436-443
Technical Paper and Note | doi.org/10.13182/NT67-A27842
Articles are hosted by Taylor and Francis Online.
An instrumental method has been devised and tested for the direct measurement of 137Cs in fission product mixtures. The method is based on beta-gamma coincidence counting, and involves beta counting of the mixture in a liquid or plastic scintillator while simultaneously measuring the gamma-ray spectrum with a NaI(Tl) detector-multichannel analyzer arrangement. Cesium-137 is unique among the long-lived fission products in that its decay (actually its 137mBa daughter, T1/2 = 2.8 min) does not involve a prompt beta-gamma coincidence. The 137Cs is then measured from a noncoincidence gamma spectrum with comparatively little interference from the other fission products. The method is not directly applicable to recently irradiated fuels but has been applied to the quantitative measurement of 137Cs in 8-month-, 1.3-year- and 2.0-year-old material with standard deviations of about 3, 0.8, and 0.7%, respectively.
