中子活化分析原理及应用简介

介绍了中子活化分析的基本原理,详细给出中子活化方程的推导过程．概述其主要特点．通过实例对其应用进行了说明。     

中子活化分析实验

本文给出一个关于中子活化分析的简易的实验方法。     

中子活化分析与地球灾变研究

你知道８０年代世界科学技术获得重大进展的十大新闻吗？用本文介绍的中子活化分析法发现了距今６５００万年前，白垩纪／第三纪（Ｋ／Ｔ）界线层中铱异常的富集，并由此提出地外物质撞击地球造成恐龙灭绝的灾变理论就是其中之一．     

不同窑口古代青瓷的产地特征的中子活化分析

产地属性是科学鉴别遗址和墓葬中出土的古陶瓷烧制产地的重要依据.用仪器中子活化（INAA）有损分析了浙江寺龙口越窑、江西洪州窑和陕西耀州窑出土的古瓷碎片样品,通过实验数据的统计分析,结果表明3个窑口古瓷的元素组成具有各自的特征,它们之间具有可以区分的依据,寺龙口越窑与南方江西洪州窑的制胎原料关系较近,与北方陕西耀州窑的关系较远.这些试验结果将为古陶瓷地研究提供重要参数.Provenance characteristic is an important scientific parameter to identify ancient porcelain wares unearthed from sites and graves.The porcelain samples of Si Long Kou kiln of Zhejiang Province,Hong Zhou kiln of Jiangxi Province and Yao Zhou kiln of Shanxi Province have been analyzed with neutron activation analysis(NAA) in this paper.The experimental data were studied with statistic methods.The results show that the chemical compositions of porcelain body samples for three kilns were different. The difference was been able identified. The body materials of both Si Long Kou Yue kiln and Hong Zhou kiln of Jiangxi were similar. The samples of Yao Zhou kiln in north of China existed obvious difference.     

秦始皇陵二号坑兵马俑原料产地的中子活化分析

选取19个秦始皇陵二号坑兵马俑样品和20个秦陵附近粘土样品,进行中子活化分析(NAA),测定每个样品中32种元素的含量,并将NAA数据进行模糊聚类分析,得到动态聚类分析图.结果表明,二号坑兵马俑样品与秦陵附近粘土样品关系密切,二号坑兵马俑的原料产地及烧制窑址可能在秦陵附近.另外,还初步研究了秦陵封土、二号坑的夯土、回填土与秦陵附近粘土的关系. 32 trace element contents in each sample are measured by neutron activation analysis for the selected that 19 samples of terracotta warriors and horses from No.2 pit of Emperor Qin Shihuang s Mausoleum, 20 samples clay nearby Qin s Mausoleum and 2 samples of Yaozhou porcelain bodies. The trend cluster analysis diagram is obtained after sortting the data. The results show that the samples from the No.2 pit of Emperor Qin Shihuang s Mausoleum have a close relationship with the clay ..     

基于瞬发伽马中子活化分析技术的金属样品检测研究

在合金材料的生产过程中,不同金属元素的含量改变对产品的性能以及可靠性有重要的影响,通过在线检测技术能够对产品中不同元素含量进行实时分析,从而指导其工业生产过程,提高产品质量。目前常规的无损检测方法受限于分析深度,无法对样品内部成分进行分析,从而影响测量结果的准确性。瞬发伽马中子活化分析（PGNAA）技术是一种高灵敏度、多元素同时分析的无损检测技术,可以对大块样品进行快速分析。针对PGNAA技术在大体积金属样品检测的可行性进行研究,通过测量快中子与样品发生非弹性散射反应激发的伽马射线对样品成分进行分析。搭建了一套测量系统,包括D-T中子发生器,中子反射体,中子准直体,高纯锗（HPGe）探测器及探测器屏蔽防护。首先,对Fe,Ti,Cr,Ni和Cu等5种金属元素进行了分析研究。对不同质量下的样品进行测量,通过伽马能谱处理软件GAMMAFIT对HPGe探测器测量到的特征伽马峰进行拟合,获得全能峰的净面积。分析全能峰净面积与样品质量之间的响应,对探测器的探测效率变化造成的非线性响应进行修正,得到不同元素的校准曲线,结果显示各元素修正后的校准曲线均具有良好的线型关系。对不同元素的质量检测限进行分析,不同金属元素的质量检测限分别为Fe（44 g）,Ti（25 g）,Cr（33 g）,Ni（108 g）和Cu（72 g）。利用测量系统对不锈钢合金样品中的Fe和Cr元素含量测量开展了研究,通过测量标准样品建立了Fe和Cr元素的定标曲线,并对未知样品进行了测量分析。同时与X射线荧光光谱（XRF）测量结果进行了对比分析,结果表明两种方法的Fe元素和Cr元素测量值偏差分别为4.08%和2.97%。研究结果表明,利用PGNAA技术可以对多种金属元素和合金样品进行测量分析,为后续其他金属样品的检测奠定了研究基础。     

中子俘获瞬发γ活化分析数据库

简要地介绍了热中子俘获瞬发γ射线数据的测量、评价、检验及其中子俘获瞬发γ射线活化分析数据库的研制、结构和基本数据内容等. The evaluation, measurement, and check of prompt γ-ray data for neutron capture are presented. The development of the database of prompt γ-ray activation analysis for neutron capture, and its structure and basical data are also described in the text.     

陕西西岳庙古琉璃胎料来源的INAA研究及多元统计分析

用仪器中子活化分析研究了陕西立地坡明代地层和陕西西岳庙宋、元、明、清早期、清晚期4个地层出土的古琉璃胎中的主量和微量元素, 并对实验数据进行多元统计分析. 结果表明, 陕西西岳庙从宋到清早期古琉璃胎料很稳定, 其原料可能来自本地； 清晚期古琉璃胎料与宋到清早期的古琉璃之间存在明显的区别, 明代3个样品和清晚期的古琉璃制造原料与立地坡出土的古琉璃其成分相近, 西岳庙清晚期的古琉璃可能来自陕西立地坡窑烧制.     

核分析技术在古陶瓷中的应用研究

古陶瓷是用瓷土加工后烧制的,它携带着的产地信息和反映古代不同时期加工工艺的年代特征,是分析和研究古陶瓷的科学依据.根据现代核分析技术的功能,阐述它在古陶瓷研究中将发挥的作用和应用前景.Ancient ceramic is fired with porcelain clay.It contains various provenance information and age characteristic.That is the scientific foundation to analyze and research the ancient ceramic with modern analysis methods.According to the property of nuclear analysis technique,the function and application of it is discussed.     

巴勒斯坦古陶瓷的显微拉曼光谱分析

本文采用显微拉曼光谱技术对巴勒斯坦古陶瓷胎体及釉面中的微米级晶粒进行测试与分析 ,结合矿物标准拉曼谱 ,实现了对多种矿物晶粒的检测与识别。研究结果表明 :显微拉曼光谱技术能够快速、准确、非破坏地测试研究古陶瓷的矿物组成 ,对古陶瓷的鉴定与分析有重要应用意义。     

Comparison of Flameless Atomic Absorption Spectroscopy with Neutron Activation Analysis for Vanadium in Beach Asphalt

One of the major arguments against using trace metal characterization as a tool to identify oil spills is lack of reliability of the data. With this in mind, the precision of flameless atomic absorption spectroscopy and of neutron activation analysis was determined for vanadium in crude oil residues. Thirty crude oil residues (beach asphalts) were analyzed by both methods, and the results compared. For neutron activation analysis, the population mean was 195 ppm, and the standard deviation of the method was 5.38 ppm. For flameless atomic absorption spectroscopy, the population mean was 202 ppm, and the standard deviation 19.5 ppm.     

用指纹元素散布分析研究古耀州瓷胎的起源

选取耀州窑瓷胎样品25个，唐三彩的胎3个，作坊匣钵料样品1个，耀州博物馆附近粘土矿样品4个．用中子活化分析测量样品中29种元素的含量，从这29种元素中挑选出8种指纹元素，将指纹元素的含量进行散布分析．结果表明，出自不同窑口的古耀州瓷的胎，有着长期稳定的、集中的原料产地．耀州窑唐三彩的胎料产地和耀州瓷胎的原料产地相同．25 samples of Yaozhou porcelain bodies, 3 samples of the tri-color pottery bodies during the Tang Dynasty, 1 samples of Saggar material during Song Dynasty and 4 samples of clay mineral taken from the place near Yaozhou Kiln Museum was selected . The technique of neutron activation analysis (NAA) has been employed to measure the content of 29 kinds of elements in the samples. 8 elements of them were selected as fingerprint elements to make scatter analysis.The conclusion is that the ancient Yaozhou por...     

可移动式中子监测隐性爆炸物系统的初步探索与研究

瞬发γ中子活化分析技术具有快速、原位、不需取样、准确、灵敏度高且能够实时多核素在线分析的特点,因此该技术是监测隐性爆炸物,尤其是非金属类爆炸物的最有效手段之一.在国内外有不少科技工作者对中子法监测隐性爆炸物技术进行了大量的研究,并取得了一定的成绩.主要对中子技术探测地雷和隐性爆炸物的各种方法和技术路线进行讨论,对同位素镅铍中子源和14 MeV脉冲中子管活化分析方法进行了初步探索研究,并对可移动式系统的源探的几何布置进行了探讨.Because it can on line analyze many elements quickly and precisely without sampling and movement, prompt gamma neutron activation analysis is one of the most effective methods to monitor latent dynamite especially nonmetal. Many researchers studied the neutron detecting latent dynamite technique and get some achievements. This paper mainly discussed each method and technology route of neutron detecting landmine and latent dynamite, studied the Am Be isotope neutron source and 14 MeV pulse neutron tube activation analysis, and analyzed the geometrical layout of movable system.     

Applications of Prompt Gamma Ray Neutron Activation Analysis: Detection of Illicit Materials

Abstract

Prompt gamma ray neutron activation analysis (PGNAA) is an efficient nondestructive multi-elemental detection technique for samples such as metals, coal (mineral), cement, and radioactive materials as well as for explosives, chemical warfare agents, various narcotics, land mines, etc. The technique can be used in the laboratory or for on-site analysis for various samples. In addition, the PGNAA technique in elemental analysis can provide more accurate detection results with low false alarm in variety of application fields when combined with image scanning and chemometric treatment of the obtained data. The development of small-sized neutron generators enabled and widened these applications because a stationary nuclear reactor is no longer an indispensible element in PGNAA.     

活化法测量中子活化在线分析系统样品处的中子能谱

用多箔活化法测定了由Am Be中子源慢化屏蔽系统构成的中子活化在线分析系统样品处的中子能谱。 根据待测场点的中子注量率水平, 选用了5种非裂变核材料箔, 其中4种是中能区和热区的, 1种是快区的, 给出了各箔片的特性参数。 通过在待测场点对箔片进行辐照, 并测量其生成放射性核的γ放射性, 计算出了各箔片的活化率。 运用SAND II和MSIT迭代方法, 解出了待测场点的中子能谱。 详细分析了数据处理过程中群截面的加工处理以及由于自屏蔽效应引起的群截面修正问题; 研究了影响解谱精度的主要因素; 对解谱结果作了一定的分析讨论; 并用蒙特卡罗(MC)方法对最后的中子能谱做了不确定度分析。     

Neutron activation analysis of sources of raw material of Emperor Qin Shi Huang’s Terracotta warriors and horses

There have been selected 83 samples of terracotta warriors and horses of Emperor Qin Shi Huang's Mausoleum, 20 samples of clays taken from around Qin's Mausoleum and 2 samples of Yaozhou porcelain bodies. All these samples have been measured by instrument neutron activation analysis (INAA) and as many as 32 kinds of element contents of each sample are measured. The following conclusion has been reached when fuzzy cluster analysis is conducted to element contents of all these samples: (i) The samples are roughly classified into five categories: namely, samples from pits No. 1 and No. 2; samples from pit No. 3; loam layers; the mixture of loam and loess; and Yaozhou porcelain bodies. (ii) The terracottawarriors and horses in pits No. 1, No. 2 and No. 3 are relatively independent from one another. The clays from which they were made are not entirely identical.We have found that samples in pit No. 3 are very closely related and their claysources are comparatively concentrated. Samples in pits No. 1 and No. 2 are less related and their clay sources are comparatively scattered. (iii) The clays from which the terracotta warriors and horses were made are closely related to theloam layer near Qin's Mausoleum, particularly to the loam layer of Zaoyuan village and Gaoxing village, but they are not so related to loess layers there, nor to the loam layers of Anhoubao, even less related to Yaozhou porcelain bodies. Arational deduction thus drawn is that the raw material of clays from which the terracotta warriors and horses were made might probably be taken from loam layers around Zaoyuan and Gaoxing, or loam layers near Qin's Mausoleum whose properties are identical with those of loam layers of Zaoyuan and Gaoxing, rather than loess layers around the above places. Since the raw material of the terracotta warriors and horses was taken from loam near Qin's Mausoleum, it could be deductedthat the kiln sites might be located in around Qin's Mausoleum.