Abstract Over the last 2 decades there has been renewed interest in developing advanced nuclear reactors and fuel cycles. Many of these advanced design concepts require or can use fuel elements that contain actinides recycled from light water reactor spent fuel. Irradiation of these elements in fast nuclear reactors is supposed to transmute them into less toxic isotopes and reduce their mass. Since transmutation is not efficient, recycling into new advanced reactor fuel must occur repeatedly to achieve a substantial reduction in mass. The introduction of this technology will create long-term proliferation risks and require safeguarding not only of plutonium, but also of the other target actinides: neptunium, americium, and curium. These elements will be present in isotopic mixtures for which information on their critical masses is unavailable. This paper provides data on critical masses and spontaneous fission neutron background for the isotopic compositions of the actinides of interest and their evolution in light water reactor fuel of various burnups and during spent fuel storage. These data are complemented by generic estimates of total inventories of these elements present in full-scale partitioning and transmutation fuel cycles being considered for commercial scale and of the time periods required for significantly reducing their proliferation potential.

中文翻译：

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分裂和嬗变核燃料循环的扩散相关性和保障影响

摘要 在过去的 20 年里，人们对开发先进的核反应堆和燃料循环重新产生了兴趣。许多这些先进的设计概念需要或可以使用包含从轻水反应堆乏燃料中回收的锕系元素的燃料元件。在快核反应堆中对这些元素进行辐照应该可以将它们转化为毒性较低的同位素并减少它们的质量。由于嬗变效率不高，必须反复循环使用新的先进反应堆燃料才能实现质量的大幅减少。这项技术的引入将带来长期的扩散风险，不仅需要保护钚，还需要保护其他目标锕系元素：镎、镅和锔。这些元素将存在于同位素混合物中，但无法获得有关其临界质量的信息。本文提供了有关锕系元素同位素组成的临界质量和自发裂变中子背景的数据，以及它们在各种燃耗的轻水反应堆燃料和乏燃料储存期间的演变。这些数据得到了对正考虑用于商业规模的全尺寸分离和嬗变燃料循环中存在的这些元素的总库存量以及显着降低其扩散潜力所需时间段的一般估计数的补充。