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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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EPA administrator Lee Zeldin talks the future of nuclear
In a recent interview on New York radio station 77 WABC, administrator of the Environmental Protection Agency Lee Zeldin talked with host John Catsimatidis about the near-term future of the domestic nuclear industry and the role the EPA will play in the sector.
Catsimatidis kicked off the interview by asking if the U.S. will be able to reach total energy independence. Zeldin responded by saying that decreasing energy dependence on other countries, especially adversaries, was a top priority for him and the Trump administration.
Yasuki Kowata, Nobuo Fukumura
Nuclear Science and Engineering | Volume 127 | Number 1 | September 1997 | Pages 89-103
Technical Paper | doi.org/10.13182/NSE97-A1923
Articles are hosted by Taylor and Francis Online.
Plutonium fuel could be utilized in the entire core of a heavy water-moderated, boiling light water-cooled pressure-tube-type reactor (HWR). The coolant void reactivity, however, depends on the various parameters of the lattice. It is especially significant to clarify the effect of plutonium nuclides on the void reactivity.The void reactivities in the infinite HWR lattices have been parametrically analyzed to clarify the effects of changes in the lattice parameters on the void reactivity using the WIMS-D4 code with the JENDL-3.1 nuclear data. At present, it is known that the behavior of the void reactivity can be clarified by separating the components of fuel nuclides, neutron cross sections, energy groups, and regions in the lattice cell from the global reactivity effect, using the important reaction rates.If the fuels are the same in the macroscopic absorption cross section for the 2200 m/s neutron, it has been shown that the void reactivity shifts further to a negative direction in a narrower pitch lattice and in the plutonium-fueled lattice with a higher content of 239Pu rather than in the uranium one. The effect of reducing the void reactivity to the negative by fissile plutonium is caused mainly by the presence of the resonance cross section at ~0.3 eV of 239Pu. The higher the content of 239Pu, the less the recovery of dipped neutron flux within the resonance energy width due to a decrease in the thermal neutron scattering of hydrogen with an increase in coolant void fraction, so that the decreased resonance fission rate for 239Pu contributes to the more negative direction for the void reactivity.On the other hand, resonance at ~0.3 eV for 241Pu does not have an important role for the void reactivity because its resonance cross section is smaller than that of 239Pu.
