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介绍了荧光玻璃探测器、热释光探测器和光释光探测器基本原理和近期发展,并总结了荧光玻璃、热释光探测器、光释光探测器的优缺点.荧光玻璃最大优点是长期稳定性好和可多次读取.热释光和光释光探测器具有灵敏度高、低探测阈、较好的稳定性和能量响应、环境适应性强等优点.但与LiF:Mg,Cu,P相比,α- Al2O3:C光释光探测器对... 相似文献
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本文探讨了1-50℃/s范围内升浊译LiF热释光探测器灵敏度和探测阈的影响。实验数据经统计处理后表明LiF(Mg.Cu,P)和LiF(Mg,Ti)-M在此范围内不同升温速率下的灵敏度和探测阈无差异。 相似文献
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国产氟化锂片型热释光探测器性能比较研究 总被引:5,自引:0,他引:5
本文报道了对常用国产LiF(Mg,Cu,P)和LiF(Mg,Ti)两类片型热释光探测器的6种产品进行剂量学性能比较研究的结果。根据国家标准“个人和环境监测用热释光剂量测量系统”的技术要求和实际需求,比较了这几种探测器的热释发光曲线,相对灵敏度,探测阈,线性度,光子能量响应,一批的均匀性,重复性和稳定性等剂量学特性。文中还对TL探测器应用中的有关问题作了讨论。 相似文献
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结合中国辐射防护研究院研制的PIG连续监测系统中对放射性碘的采样、测量和数据分析方法,按ISO规定的判断阈和探测限的计算原则确定了PIG连续监测系统放射性碘监测部分的判断阈和探测限. 相似文献
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黄玉龙 《核电子学与探测技术》1985,(5)
热释光技术已广泛地用于辐射剂量监测。由于热释光探测元件有方片、圆片、圆棒及粉末等形式,应用不同测量元件需更换不同的测量盘;此外,测量盘用久变黑也需更换。在更换的过程中,极易碰断热电偶丝。本文介绍一种热电偶焊接器和焊接方法,较满意地解决了这个问题。 相似文献
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Characteristics of pulsed photo-stimulated luminescence and thermoluminescence for the identification of gamma irradiated poultry eggs 总被引:1,自引:0,他引:1
Pulsed photo-stimulated luminescence (PPSL) is a simple screening method that can be employed qualitatively at the spot for the detection of eggs treated with ionizing radiation.Due to the variations in the results during storage,the eggs of ostrich,duck,hen,and quail were irradiated to doses of 0,1,2,and 3 kGy.Most of the samples were incorrectly identified during storage after four months of irradiation.Thermoluminescence (TL) technique was also tried by using egg shells in order to confirm the irradiation treatment in eggs.TL glow curves were recorded between the temperatures 50℃to 400℃at the rate of 5°/s for all the control and irradiated samples.On the basis of integrated areas of first glow curves (TL1),the glow curve ratios (TL1/TL2) and the shapes of maxima of TL1, the irradiation treatment of all the eggs was confirmed.Furthermore,the presence of calcite and aragonite minerals that cause the TL signal in the egg shells were studied using X-ray diffraction spectrometry. 相似文献
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为有效实现数字射线扫描成像检测系统性能的定量分析评价,据此进行检测工艺参数的优化,对数字射线扫描成像检测系统调制传递函数(Modulation transfer function,MTF)进行了测试分析。采用刀口工具、双线型像质计、分辨率测试卡,对系统在不同焦点大小、放大倍数、运动方向的检测情况,分别进行了MTF的测试并进行了比较。结果表明,双线型像质计与分辨率测试卡的测试结果基本一致,但双线型像质计更便于对比度的定量计算;双线型像质计的对比度传递函数近似符合二次曲线,经转换得到的调制传递函数值高于刀口法的测试值,刀口法计算数值偏低的原因在于运动不平稳所带来的不利影响。分析表明,数字射线扫描成像系统性能受到多个因素的共同影响,MTF测试结果可较全面地对影响因素进行定量评价,可用于确定最佳的检测参数或找出等价的参数组合。 相似文献
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基于物理体模CT图像的1岁儿童体素体模构建 总被引:1,自引:1,他引:0
本文介绍了基于1岁儿童物理体模(Model 704-D)的CT图像和中国成年男性参考人体素体模(CRAM)的1岁儿童体素体模(CPP01)的构建,包括通过对物理体模扫描得到OCP01体模(基于儿童物理体模的CT图像建立的一粗略的体素体模),进而构建和优化CPP01。该体素体模的各器官组织的质量与GBZ/T 200.2-2007所给数据的相对偏差约在5%以内,且其外部轮廓和主要器官的位置与Model 704-D相匹配。 相似文献
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The monitoring results of gross α and gross β activity from 2001 to 2005 for environmental airborne aerosol samples around the Qinshan NPP base are presented in this paper. A total of 170 aerosol samples were collected from monitoring sites of Caichenmen village, Qinlian village, Xiajiawan village and Yangliucun village around the Qinshan NPP base. The measured specific activity of gross α and gross β are in the range of 0.02 ~ 0.38 mBq/m3 and 0.10 ~ 1.81 mBq/m3, respectively, with an average of 0.11 mBq/m3 and 0.45mBq/m3, respectively. They are lower than the average of 0.15 mBq/m3 and 0.52mBq/m3, of reference site at Hangzhou City. It is indicated that the specific activity of gross α and gross β for environmental aerosol samples around the Qinshan NPP base had not been increased in normal operating conditions of the NPP. 相似文献
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LIN Qian CAO Xuewu 《核技术(英文版)》2007,18(4):242-246
Fuel Coolant Interactions (FCIs) are important issues in nuclear reactor severe accident analysis. In FCIs, fragmentation model of molten droplets is a key factor to estimate degree of possible damage. In this paper, the mixing process in FCIs is studied by the simulation of MIXA experiment with hydrodynamic fragmentation model. The result shows that hydrodynamic fragmentation model underestimates the fragmentation rate of high temperature molten droplets under the condition of low Weber numbers. It is concluded that models based on thermal fragmentation mechanism should be adopted to analyze the FCI process and its consequence. 相似文献
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D.D. Neufeld Y. PuF.B. Dunning 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2011,269(11):1288-1291
The stray electric “patch” fields present at a Au(1 1 1) surface are investigated by studying the ionization of Rydberg atoms incident at near-grazing angles. Measurements of the threshold conditions required to observe the resulting ions are used to estimate how large such stray fields can be. The data show that the stray fields can be sizeable, as large as ∼103 V cm−1 100 nm from the surface and ∼20 V cm−1 500 nm from the surface, and illustrate the potential of Rydberg atoms for detecting and characterizing surface electric fields. 相似文献
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HUANG Xiaolong WANG Baosong 《核技术(英文版)》2007,18(5):261-267
213Bi disintegrates (97.91±0.03) % by β- emission to the levels in 213po, and (2.09±0.03) % through α decay to 209Tl. The evaluation of the complete decay scheme and data of 213Bi including the recent new measurements are presented in this report. The Limitation of Relative Statistical Weight Method (LWM) was applied to average numbers throughout the evaluation. The uncertainty assigned to the average value was always greater than or equal to the smallest uncertainty of the values used to calculate the average. The half-life is determined to be 45.59±0.06 minutes. All known measured gamma-ray relative emission probabilities have been examined. And the gamma-ray emission probability of the reference γ line of 440.44keV is recommended to be (26.1±0.3) %. The calculated internal conversion coefficients and their uncertainties have been used to obtain the complete decay intensity balance. The other decay characteristics are calculated using the ENSDF analysis program. Finally the new 213Bi decay scheme was re-built. 相似文献
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LI Tianshu YANG Yanhua YUAN Minghao HU Zhihua 《核技术(英文版)》2007,18(5):311-315
An observable experiment facility for low-temperature molten materials to be dropped into water was set up in this study to investigate the mechanism of the vapor explosion. The effect of the fuel and coolant interaction (FCI) on the vapor explosion during the severe accidents of a fission nuclear reactor has been studied. The experiment results showed that the molten material temperature has an important effect on the vapor explosion behavior and pressure. The increase of the coolant temperature would decrease the pressure of the vapor explosion. 相似文献