共查询到16条相似文献,搜索用时 46 毫秒
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本文叙述了用感应炉熔炼及铸造锆-8.5wt%铀合金棒的工艺。铸棒的成份均匀,上下端面铀含量偏差不大于0.1%,因涂层坩埚带入的杂质含量均在允许范围,铸棒质量良好,合金的收得率为90%,用该工艺生产脉冲堆燃料棒要比电弧熔炼、挤压成型工艺简单,经济效益显著。 相似文献
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以光纤光度计为检测仪,百里酚为显色剂,用分光光度法测定了铀及铀铌合金中的氮含量。在次氯酸钠溶液中w(Cl)=0.1%~0.14%的条件下,氨与酚形成的络合物最大吸收波长为660nm,方法检测限为20μg/g,测量相对标准偏差小于15%,方法回收率为88%~106%。经比对,该法测定结果与传统分光光度法基本一致。 相似文献
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用压力-体积-温度(P—V—T)法研究了铀和铀铌合金与氢气反应的动力学过程。研究结果表明,加热预处理可以缩短铀和铀铌合金试样与氢气反应的孕育期;加热预处理温度(600-700℃)对铀和铀铌合金与氢气反应的影响不同。加热预处理温度为600℃、反应温度为200℃时,低碳铀、高碳铀、铀-7%铌合金和铀-3.5%铌合金与氢气反应的活性依次增强。因此,高碳铀和铀铌合金比低碳铀更易于与氢气反应。 相似文献
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采用离子选择电极分析技术测量了铀及铀铌合金中的微量氮,确定了ISA作为离子强度调节剂缓冲溶液时该方法的最佳试验条件.结果表明,温度控制在(25±1)℃、pH=4.5~5.0,铵离子电极检测下限为0.03mg/L,回收率为85%~98%,方法的测量相对标准偏差小于15%;在氮含量为30~80 μg/g范围内,测氮结果与传... 相似文献
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感应熔炼锆铀合金的坩埚涂层 总被引:1,自引:0,他引:1
本文简述了用涂层石墨坩埚进行感应熔炼活性金属的现状以及不同涂层的石墨试片经1950℃高温处理后观测到的相容性。用17种涂层坩埚熔炼Zr-8.5wt%U合金表明:与合金熔体相容较好的均是内层有碳化物过渡、外层为氧化钇的某些复合涂层坩埚,该涂层对抑制熔体的侵蚀和浸润有一定的作用;熔铸的合金棒经分析、检验及渗氢处理均得到了满意结果。 相似文献
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《Journal of Nuclear Science and Technology》2013,50(4):537-539
The Doppler reactivity effect of 238U was measured in simulated MOX fuel using the FCA facility for the purpose of obtaining data on the 238U Doppler reactivity effect in light-water-moderated MOX fuel and evaluating the prediction accuracy of the current analysis code systems and nuclear data library. Experimental data on the Doppler reactivity effect from room temperature up to 800°C were obtained for a uranium fueled core and mockup cores for MOX-fueled LWR using cylindrical natural-uranium samples. With the use of various samples with various neutron spectra, 238U Doppler reactivity effects at energies generally in the low range below 1 keV were evaluated. Analyses were performed using the current standard analysis code systems for fast and thermal reactors, with the JENDL-3.3 data library. Both analyses yielded calculated/experimental value (C/E) ratios of 0.96 to 1.06 for the MOX cores, a good agreement within the experimental error, and those in the uranium core were similar. 相似文献
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贫化铀及组合球中的反应率测量 总被引:1,自引:1,他引:0
用HPGe探测器测量了DT中子照射下^27Al(n,α)^24Na、^197Au(n,2n)^196Au、^93Nb(n,2n)^92Nbm和^197Au(n,γ)^198Au几个反应在贫化铀、贫化铀/聚乙烯/铁组合球中的活化率。运用MCNP/4B程序和ENDF/B-Ⅵ数据库对实验进行了模拟计算^27Al(n,α)^24Na、^197Au(n,2n)^196Au反应的计算与实验结果基本一致,而^197Au(n,γ)^198Au反应的计算结果与实验结果有相当大的差异。 相似文献
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《Journal of Nuclear Science and Technology》2013,50(6):350-355
The carbothermic reaction of UN with graphite in the form of loose powder mixture has been studied in vacuo with the aid of a high-temperature thermobalance in the temperature range of 1,270~1,675°C. The gravimetric measurements were conducted continuously to determine the effect of varying reaction temperature and differences in sample particle size. The kinetics of the reaction was found to follow the diffusion—controlled kinetic equation for mixed powder, and activation energies of 76.1, 55.1 and 72.7kcal/mol were obtained for samples of (1)—400 mesh UN and—400 mesh natural graphite mixture, (2)—150 +270 mesh UN and—150 +270 mesh natural graphite mixture, and (3)—150 +270 mesh UN and—150 +270 mesh artificial graphite mixture, respectively. X-ray diffraction studies revealed the reaction products of the coarse sample to be composed of two different kinds of UCxN1-x solid solutions, one having a x value of 0~0.2, and the other 0.8~0.9. From the above observations, the diffusion of C and/or N atoms through the outer carbon rich UCxN1-x layer may be considered to be the rate determining step. 相似文献