排序方式: 共有23条查询结果,搜索用时 15 毫秒
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瞬发伽玛活化分析中3种探测器性能比较 总被引:1,自引:0,他引:1
利用中国先进研究堆(CARR)热中子束流孔道首次开展了瞬发伽玛中子活化分析(PGNAA)实验。对NH4Cl、Si、Fe、Al等4种样品进行了辐照,同时采用HPGe、LaBr_3、BGO 3种探测器对样品进行实时测量,在瞬发伽玛射线的能量为0.002~10 MeV范围内研究了3种探测器在宽能区的能量线性、能量分辨率、探测效率等性能。 相似文献
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Tian Weizhi 《中国工程科学》2009,11(4):101-122
The history, the major achievements in both methodology and applications, the current trends and future perspectives of neutron activation analysis (NAA) in China are briefly described. 相似文献
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A prompt gamma neutron activation analysis(PGNAA)set-up was developed for the elements detection in aqueous solution,which includes a 241Am-Be neutron source and a 4-inch BGO detector.The geometry of set-up is determined by a series of simulations with the MOCA code to improve the efficiency of the elements detection.The thermal neutron flux and the gamma-ray self-absorption are considered during the optimization calculations.Experiments were performed to validate the set-up using samples including chlorine and mercury,respectively.The result shows that the characteristic peak count has linear relationship with the chlorine and mercury concentration changing.The minimum detectable concentrations of chlorine and mercury were found as 54 mg/L and 51.4 mg/L,respectively. 相似文献
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R. Khelifi A. Amokrane 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2007,262(2):329-332
A basic PGNAA facility with an Am-Be neutron source is described to analyze the pollutants in water. The properties of neutron flux were determined by MCNP calculations. In order to determine the efficiency curve of a HPGe detector, the prompt-gamma rays from chlorine were used and an exponential curve was fitted. The detection limits for typical water sample are also estimated using the statistical fluctuations of the background level in the areas of recorded the prompt-gamma spectrum. 相似文献
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Estimation of minimum detectable concentration of chlorine in the blast furnace slag cement concrete
A.A. Naqvi M. MaslehuddinM.A. Garwan M.M. NagadiO.S.B. Al-Amoudi Khateeb-ur-RehmanM. Raashid 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2011,269(1):1-6
The Prompt Gamma Neutron Activation Analysis technique was used to measure the concentration of chloride in the blast furnace slag (BFS) cement concrete to assess the possibility of reinforcement corrosion. The experimental setup was optimized using Monte Carlo calculations. The BFS concrete specimens containing 0.8-3.5 wt.% chloride were prepared and the concentration of chlorine was evaluated by determining the yield of 6.11, 6.62, 7.41, 7.79 and 8.58 MeV gamma-rays.The Minimum Detectable Concentration (MDC) of chlorine in the BFS cement concrete was estimated. The best value of MDC limit of chlorine in the BFS cement concrete was found to be 0.034 ± 0.011 and 0.038 ± 0.012 wt.% for 6.11 and 6.62 MeV prompt gamma-rays. Within the statistical uncertainty the lower bound of the measured MDC of chlorine in the BFS cement concrete meets the maximum permissible limit of 0.03 wt.% of chloride set by the American Concrete Institute. 相似文献
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Z. Idiri H. Mazrou S. Bedek 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2010,268(2):213-107
A prompt gamma neutron activation analysis (PGNAA) set-up with an Am-Be source developed for in situ analysis of liquid samples is described. The linearity of its response was tested for chlorine and cadmium dissolved in water. Prompt gamma efficiency of the system has been determined experimentally using prompt gamma of chlorine dissolved in water and detection limits for different elements have been derived for domestic waste water. A methodology to analyze any kind of liquid is then proposed. This methodology consists mainly on using standards with water as bulk or in the case of absolute method, to use gamma efficiency determined with prompt gammas emitted by chlorine dissolved in water. To take into account the thermal neutron flux variations inside the samples, flux monitoring was carried out using a He-3 neutron detector placed at the external sample container surface. Finally, to correct for the differences in gamma attenuation, average gamma attenuations factors were calculated using MCNP5 code. This method was then checked successfully by determining cadmium in industrial phosphoric acid and our result was in good agreement with that obtained with inductively coupled plasma (ICP) method. 相似文献
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煤质在线自动分析系统的开发及其工业应用 总被引:1,自引:0,他引:1
本文主要介绍利用瞬发γ射线中子活化分析PGNAA(PromptGammaNeutronActivationAnalysis)技术分析煤中各元素的组成及其含量的原理、基本方法和它在电力煤炭等工业领域的应用。 相似文献
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用于瞬发γ中子活化在线元素分析的高计数率γ谱仪 总被引:3,自引:1,他引:2
孟伯年 《核电子学与探测技术》1995,15(1):1-12
高纯锗探测器制技术及谱仪电子学的迅速发展,使瞬发γ中子活化分析所要求的高计数率γ谱仪已可以由适当地选择谱仪系统中的各个部件而实现,本文针对PGNAA的应用,就高计数率γ谱仪对各训件指标的要求与选择依据及系统总体考虑进行介绍,并给出系统所能达到的总性能参数。 相似文献
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