Isochronous mass spectrometry in storage rings is a successful technique for the precision mass measurements ofthe nuclides with half-lives down to tens of microseconds[1]. Since the isochronous condition =t greatly r...Isochronous mass spectrometry in storage rings is a successful technique for the precision mass measurements ofthe nuclides with half-lives down to tens of microseconds[1]. Since the isochronous condition =t greatly reducesthe influence of the velocity difference on the ion revolution periods, the revolution period difference ΔT =T ??TRof a stored ion with respect to a reference time TR is directly related to its mass-to-charge ratio difference Δ(m=q),written in the first order as:展开更多
采用液态燃料及重水慢化剂的重水慢化熔盐堆(Heavy Water moderated Molten Salt Reactor,HWMSR)具有高中子经济性,但堆芯出口温差较大,将会导致堆芯顶部管道构件热疲劳。本文旨在优化HWMSR堆芯设计,降低堆芯出口温差。采用中子学-热工...采用液态燃料及重水慢化剂的重水慢化熔盐堆(Heavy Water moderated Molten Salt Reactor,HWMSR)具有高中子经济性,但堆芯出口温差较大,将会导致堆芯顶部管道构件热疲劳。本文旨在优化HWMSR堆芯设计,降低堆芯出口温差。采用中子学-热工耦合程序以及堆芯临界搜索程序,深入分析了具有不同熔盐通道半径堆芯的功率分布、熔盐出口温度分布、初始易裂变核素233U装载量及钍铀增殖等性能。结果表明:增大堆芯内区熔盐通道尺寸将降低燃料熔盐功率密度峰值及最大出口温度,而对钍铀增殖比及^(233)U初始装载量影响非常有限。本研究为优化重水慢化熔盐堆堆芯设计提供参考。展开更多
文摘Isochronous mass spectrometry in storage rings is a successful technique for the precision mass measurements ofthe nuclides with half-lives down to tens of microseconds[1]. Since the isochronous condition =t greatly reducesthe influence of the velocity difference on the ion revolution periods, the revolution period difference ΔT =T ??TRof a stored ion with respect to a reference time TR is directly related to its mass-to-charge ratio difference Δ(m=q),written in the first order as:
文摘CMSX-4是目前世界上应用最广泛的第二代镍基单晶高温合金,在CMSX-4中添加微量的镧(La),铈(Ce)等稀土元素可以显著提高合金的抗氧化性和耐腐蚀性。本文建立了湿法消解-电感耦合等离子体质谱法(ICP-MS)同时测定CMSX-4镍基高温合金中La, Ce元素含量的方法。样品经王水-HF常压加热溶解,利用HClO4冒烟消除F-的干扰,优化了溶样用酸的量和消解条件。在优化条件下,方法的检出限为La 0.23μg/g, Ce 0.85μg/g,加标回收率为95.0%~98.9%,相对标准偏差(RSD)为1.3%~3.9%,能够用于对CMSX-4镍基高温合金中微量La和Ce元素的准确、快速测定。
文摘采用液态燃料及重水慢化剂的重水慢化熔盐堆(Heavy Water moderated Molten Salt Reactor,HWMSR)具有高中子经济性,但堆芯出口温差较大,将会导致堆芯顶部管道构件热疲劳。本文旨在优化HWMSR堆芯设计,降低堆芯出口温差。采用中子学-热工耦合程序以及堆芯临界搜索程序,深入分析了具有不同熔盐通道半径堆芯的功率分布、熔盐出口温度分布、初始易裂变核素233U装载量及钍铀增殖等性能。结果表明:增大堆芯内区熔盐通道尺寸将降低燃料熔盐功率密度峰值及最大出口温度,而对钍铀增殖比及^(233)U初始装载量影响非常有限。本研究为优化重水慢化熔盐堆堆芯设计提供参考。