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2026 ANS Annual Conference
May 31–June 3, 2026
Denver, CO|Sheraton Denver
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Christmas Light
’Twas the night before Christmas when all through the house
No electrons were flowing through even my mouse.
All devices were plugged by the chimney with care
With the hope that St. Nikola Tesla would share.
Mohamed S. El-Genk, Huimin Xue, Dmitry Paramonov
Nuclear Technology | Volume 105 | Number 1 | January 1994 | Pages 70-86
Technical Paper | Special on Nuclear Criticality Safety / Nuclear Reactor Safety | doi.org/10.13182/NT94-A34912
Articles are hosted by Taylor and Francis Online.
The thermionic transient analysis model is used to simulate the startup of the TOPAZ-II space nuclear power system in orbit. The simulated startup procedures are assumed for the purpose of demonstrating the capabilities of the model and may not represent an accurate account of the actual startup procedures of the TOPAZ-II system. The temperature reactivity feedback effects of the moderator, UO2 fuel, electrodes, coolant, and other components in the core are calculated, and their effects on the thermal and criticality conditions of the reactor are investigated. Also, estimates of the time constants of the temperature reactivity feedback for the UO2fuel and the ZrH moderator during startup, as well as of the total temperature reactivity feedback as a function of the reactor steady-state thermal power, are obtained.
