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The objectives of MSTD are: promote the advancement of materials science in Nuclear Science Technology; support the multidisciplines which constitute it; encourage research by providing a forum for the presentation, exchange, and documentation of relevant information; promote the interaction and communication among its members; and recognize and reward its members for significant contributions to the field of materials science in nuclear technology.
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2024 ANS Winter Conference and Expo
November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
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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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New laws offer nuclear industry incentives for existing power plant uprates
This year, the U.S. nuclear industry received a much-needed economic boost that could help preserve operating nuclear power plants and incentivize upgrades that extend their lifespan and power output.
Signed into law in 2022, the Inflation Reduction Act offers production tax credits (PTCs) for existing nuclear power plants and either PTCs or investment tax credits (ITCs) for new carbon-free generation. These credits could make power uprates—increasing the maximum power level at which a commercial plant may operate—a much more appealing option for utilities.
G. C. Baldwin
Nuclear Science and Engineering | Volume 6 | Number 4 | October 1959 | Pages 320-327
Technical Paper | doi.org/10.13182/NSE59-A28851
Articles are hosted by Taylor and Francis Online.
The kinetics of the two-core configuration of the Argonaut reactor is examined. In this reactor two slightly subcritical slabs two feet apart are immersed in a large graphite reflector. The system achieves criticality by the small interaction due to exchange of thermal neutrons between the cores. The kinetic equations are derived by including an interaction term with the source terms of the thermal neutron diffusion equation, and writing a separate diffusion equation for each slab. This analysis accounts for observations that the ratio of flux levels in the two cores may depart considerably from unity although the reactor shows a single stable period. It is shown that the reactivity change which a rod in one core must introduce to restore criticality after a change is made in the other core is generally not equal in magnitude to that of the change which it compensates. Flux ratio as well as period must be known to determine the excess reactivities; conventional rod calibration data must be corrected for a progressive shift in flux ratio as reactivity is traded between rods. The rod drop method is discussed with two examples; a single relation does not suffice to describe the rod drop procedure. The single transfer function of a simple reactor system is replaced by a set of six transfer functions for the two-core system, two of which are derived for illustration. Even though an oscillator may be located midway between them, the amplitudes and phases of flux in the two cores will not agree except in the special situation of identical cores and equal flux levels. This complicates the problem of regulation.