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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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Latest News
Wright denies reports of DOE plans to axe Hanford’s WTP
Energy Secretary Chris Wright issued a statement on September 9 denying reports that the Department of Energy plans to terminate the Waste Isolation Pilot Plant (WTP) at the Hanford Site in Washington state.
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.
