共查询到16条相似文献,搜索用时 109 毫秒
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固体径迹法测量水泥反射体中~(252)Cf中子源反射中子 总被引:1,自引:0,他引:1
叙述了水泥反射体中~(252)Cf中子源反射中子测量实验原理。测量了无反射体、有反射体、本底三种状态下中子引发~(235)U产生的裂变率。并根据裂变率得到实验模型下水泥反射体对中子的反射系数。比较了不同中子源相同实验模型水泥反射体对中子的反射系数,对反射系数随角度变化趋势进行了分析。同时,对固体径迹探测技术进行了研究,探索了最佳蚀刻条件,得到火花放电计数随信号膜质量厚度及蚀刻厚度变化趋势。标定了固体径迹火花自动计数器效率,发展了固体径迹探测技术。 相似文献
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火花计数器是一种自动计数的固体核径迹探测器。这种方法计数快,结构简单,操作方便,可以解脱繁重的目视测量。与垂直入射的裂片径迹相比,以2π立体角入射的裂片径迹火花计数技术有其自身特点。裂片以2π立体角射入薄膜,在一定蚀刻条件下,膜上蚀成的孔洞径迹,只是记录径迹的一部分。显然,膜越薄,灵敏度越高;蚀刻时间越长,孔洞径迹占的比例越大,火花计数也越多。我们取火花计数与膜上被蚀刻出的总径迹数之比为火花计数效率。同一片蚀刻过的膜,多次进行火花计数,其脉冲数不完全相同。若多 相似文献
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5种固体径迹氡探测器某些性能的比较以及火花计数器的改进 总被引:1,自引:1,他引:0
对5种固体径迹氡探测器的相对误差、探测下限和探测效率等性能作比较测试后,推荐出一种有推广价值的探测器。改进了火花计数器的成形电路,并对计数器中心电极尺寸、重物等予以研究。改进后的火花计数器的径迹密度测量上限经“重孔”校正后,对直径为21、16和11mm的中心电极分别为4000、4600和5000/cm~2。 相似文献
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A study has been made of the resolving power of plane-parallel spark counters with small working gap and high pressure of the gas mixture. It is shown that the resolution time of such counters may reach 10–10 sec. 相似文献
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《Journal of Nuclear Science and Technology》2013,50(5):329-342
Fast neutron spectra were measured at the core centers of two plutonium-fuelled assemblies of FCA by the proton-recoil counter technique. Small cylindrical counters with field tubes made by metallizing a ceramic-seal surface were constructed. The filling gases, hydrogen and methane, were purified to reduce the concentration of electronegative impurites. The highest resolutions measured by 3He(n, p,3T reaction were 3.8 and 5.5% (FWHM) for the hydrogen-filled and methane-filled counters respectively. Gamma-induced background was rejected by the pulse-shape discrimination technique, using a digital processing arithmetic unit and a two-dimensional pluse height analyzer. The spectrum measurement over a wide energy range was carried out by different settings of the main amplifier gain and of the gas multiplication of the counters; its energy ranged from 2.5 keV to 2 MeV. Measurements were made with the energy resolution about 10% (FWHW) or less at energies down to 5 keV. The measured neutron spectra are compared with calculated spectra, obtained by the cell program SP-2000 with the fine group cross section library AGLI. The comparisons indicate that the measured spectra are in good agreement with the calculated spectra except near the large iron and oxygen resonances. 相似文献