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公开(公告)号:US06445759B1
公开(公告)日:2002-09-03
申请号:US09689789
申请日:2000-10-13
申请人: Kouji Hiraiwa , Yamato Hayashi , Yasushi Hirano , Jun Saeki , Kazuki Hida , Junko Watanabe
发明人: Kouji Hiraiwa , Yamato Hayashi , Yasushi Hirano , Jun Saeki , Kazuki Hida , Junko Watanabe
IPC分类号: G21C300
CPC分类号: G21C7/04 , G21C3/326 , G21Y2002/201 , G21Y2004/10 , G21Y2004/30 , Y02E30/38 , Y02E30/39
摘要: A fuel assembly comprises a plurality of fuel rods bundled in grid pattern, a part of the fuel rods containing gadolinium as a burnable poison. At least one of the fuel rod having gadolinium contains gadolinium enriched in at least one kind of isotope of odd mass number more than an isotopic abundance of natural gadolinium. In the enriched gadolinium, a ratio of a content of Gd-155 to that of Gd-157 is 0.1 or less. An average concentration (wt %) G0 of enriched gadolinia is, with M denoting the number of month under rated power operation per one cycle of an equilibrium core, P power density of a nuclear reactor (kw/l unit) and W a sum of isotopic composition, is set in the range shown by the following expression. G0
摘要翻译: 燃料组件包括多个以栅格图案捆扎的燃料棒,燃料棒的一部分包含钆作为可燃毒物。 具有钆的燃料棒中的至少一个含有富含至少一种比天然钆的同位素丰度高的奇数质量的至少一种同位素的钆。 在富集的钆中,Gd-155与Gd-157的含有率为0.1以下。 富氧钆的平均浓度(wt%)G0,M表示平衡核心每一个循环的额定功率运行下的月数,核反应堆的功率密度(kw / l单位)和W是 同位素组成设定在由下式表示的范围内。因此,在燃料组件中,可以减少循环端的可燃毒物的残留反应性,并且可以提高热性能。在燃料组件的另一方面,a 设置在控制杆侧的区域中的钆氧燃料棒包含富含奇数质量数超过天然同位素丰度的同位素的钆。 富集钆的浓度设定为例如天然钆的一半以下。 因此,氧化钆燃料棒中的易裂变材料(铀)的富集可以大于现有的燃料组件中的裂变材料(铀)的浓缩,钚的平均浓度增加。
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公开(公告)号:US5194207A
公开(公告)日:1993-03-16
申请号:US711873
申请日:1991-06-07
申请人: Isamu Tokuda , Kiyohiko Matsumoto , Jun Saeki
发明人: Isamu Tokuda , Kiyohiko Matsumoto , Jun Saeki
CPC分类号: A01K87/06 , B29C33/485 , B29C70/74 , B29C45/00 , B29L2031/7002
摘要: A fishing rod is manufactured by forming a tubular small diameter portion on an outer surface of a rod material. The small diameter portion is formed continuous with and between a pair of walls substantially perpendicular to an axis of the rod material. Then a seat base is formed by placing a pair of dies around the small diameter portion and injecting a heated thermoplastic resin into a cavity (inside space) defined by the dies.
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