X射线能量变化对其在炸药中衰减规律的研究

在管电流和药柱一定的条件下,通过改变X射线源能量对某炸药进行了X射线穿透检测,利用回归分析方法对测得的X射线在某炸药中的穿透率进行拟合。通过对拟合结果分析得出了X射线在某炸药中的衰减规律符合二次拟合。同时得到杂质的密度越大,衰减越明显;不同厚度的同一杂质,厚度大的衰减明显,但当管电压达到一定值时,射线衰减趋于不变。     

60Co γ射线在炸药柱中衰减规律的实验研究

利用最小二乘法对测得的不同厚度的炸药柱的计数率进行拟合，得到γ射线在某炸药中的衰减服从指数规律，且线性吸收系数为1．007。     

部分种子成分的特征X射线在等效生物材料中衰减的测定

用Ｓｉ（Ｌｉ）探测器实现了Ｎａ、Ｍｇ、Ｓ、Ｃｌ的特征Ｘ射线在有机膜中的相对衰减以及与Ｏ、Ｋ元素的特征Ｘ射线能量相当的Ｘ射线或轫致辐射在有机膜中的相对衰减，分别得出了它们减的数学描述，并把实验得到不同能量的Ｘ射线在有机膜中的质量吸收系数与Ｂｅｒｋｅｌｅｙ的ＯＣＧ软件计算出的结果相比，相关都小于３０％。     

直流X射线模拟电缆X射线响应的可行性

本文对电缆X射线辐照响应的机理和模拟方法进行了研究,分析了电缆直流和脉冲X射线辐照响应的异同。建立了带状电缆X射线辐照响应一维计算模型,该模型包含电缆屏蔽层和介质层间隙、介质层瞬态辐射感应电导率等计算模型,模拟了带状电缆直流和脉冲X射线辐照电流响应。模拟结果表明,在X射线注量相同的条件下,电缆直流和方波脉冲X射线响应具有类似的波形特征及相同的间隙电压。因此,在该计算模型描述的电缆X射线辐照响应机制下,可利用直流X射线开展相应的脉冲X射线辐照响应机制模拟。     

X射线荧光分析中基本参数法的应用

文章使用基本参数法,对合金钢样品不经化学处理,不使用参考标准,样品在同位素源激发的Si(Li)X射线荧光谱仪上进行测量,将测量结果送入同多道联机的EMG 666微机上进行计算,最后打印出分析结果。文中对入射角的变化,一次荧光效应和二次荧光效应,散射效应进行了研究,并对合金钢样进行了分析。用标准样品检验,表示分析准确度的相对误差小于±3%;表示方法精密度的相对偏差小于±6%。     

X射线荧光光谱仪的现状

综述了波长色散X射线荧光光谱仪和能量色散X射线荧光光谱仪的现状和发展趋势,及其X射线荧光光谱仪的拓展,介绍了部分具有代表性的X射线荧光光谱仪的主要性能.     

使用X光聚束系统的X射线荧光分析研究

复合光导管组成的Ｘ光透镜可将发散的Ｘ光束聚至直径φ０．５ｍｍ，聚束后的功率密度增加１０＾４倍，这种新型的Ｘ光透镜已用于Ｘ射线荧光分析研究，使用Ｘ光管功率仅２Ｗ，而探测限可达１０＾－９－１０＾１０ｇ．     

X射线荧光分析中基本参数法的应用

本文使用基本参数法,对合金钢样品不经化学处理,不使用参考标准,样品在~(238)Pu同位素源激发的Si(Li)探测器组成的X射线荧光谱仪上进行测量,将测量结果送入同多道分析器联机的EMG666微机上进行计算,最后打印出结果。文中对入射角的变化、一次荧光效应、二次荧光效应和散射效应进行了研究;对核电站的合金钢样进行了分析,用标准样品检验方     

用同步辐射X射线荧光微区分析技术测定单晶硅中的掺杂元素As

利用同步辐射Ｘ射线微区分析技术，研究了单晶硅中掺杂元素Ａｓ浓度的定量分布，并对结果进行了讨论。     

利用TNA方法进行爆炸物检测软件系统中的能谱自动分析

主要研究利用TNA方法进行爆炸物检测中的能谱自动分析算法,包括在干扰环境下对能谱进行稳谱,利用已完成能量刻度的标准谱对探测器采集的能谱进行自动能量刻度,以及对刻度后的能谱进行快速拟合或积分,计算样品中的N和H元素的含量.通过不同的数值分析算法,能够对能谱进行快速、准确的自动分析处理,为最终实现爆炸物检测奠定基础.     

利用脉冲快热中子分析方法和神经网络识别爆炸物

研究利用PFTNA方法和人工神经网络来识别爆炸物的方法。该方法利用PFTNA来获取被检测样品的热中子俘获γ谱和γ快中子非弹性散射谱,然后通过已知能谱对人工神经网络进行训练后识别未知样品。利用这种方法,能够快速的对未知样品进行定性分析。     

Homogeneity study of an Fe impurity in unalloyed Zn using PIXE

We have studied the distribution of an Fe impurity in unalloyed Zn material along line scans in spots of 1 mm diameter each using PIXE. In order to achieve the necessary precision (1%) in the determination of this low Fe content (about 100 mg/kg), a sufficient counting rate of Fe X-rays is needed without overloading the counting electronics with Zn X-rays at the same time. Therefore, the development of our PIXE analysis system had to take into account: (a) optimising the thickness of a Ni absorber foil in order to selectively reduce the counting rate of Zn without adding an unproportionally high Ni counting rate, (b) implementing a triggered ion beam deflection system capable of handling very high counting rates (up to 8 kcps), (c) developing the spectrum evaluation code to take account of the selective absorption by the Ni foil. The results of our PIXE measurements showed an inhomogeneity in Fe of up to 10%, considered too high to accept this zinc material as a new reference material.     

Influence of impurity seeding on the plasma radiation in the EAST tokamak

Plasma radiation characteristics in EAST argon(Ar) gas and neon(Ne) gas seeding experiments are studied.The radiation profiles reconstructed from the fast bolometer measurement data by tomography method are compared with the ones got from the simulation program based on corona model.And the simulation results coincide roughly with the experimental data.For Ar seeding discharges,the substantial enhanced radiations can be generally observed in the edge areas at normalized radius ρ_(pol)~0.7–0.9,while the enhanced regions are more outer for Ne seeding discharges.The influence of seeded Ar gas on the core radiation is related to the injected position.In discharges with LSN divertor configuration,the Ar ions can permeate into the core region more easily when being injected from the opposite upper divertor ports.In USN divertor configuration,the W impurity sputtered from the upper divertor target plates are observed to be an important contributor to the increase of the core radiation no matter impurity seeding from any ports.The maximum radiated power fractions f_(rad)(P_(rad)/P_(heat)) about 60%–70% have been achieved in the recent EAST experimental campaign in 2015–2016.     

一种基于双能X射线与前向散射的爆炸物检测方法

本文简要介绍了爆炸物检测领域的各种现行方法,指出了它们的优缺点。与它们相比,本文探讨的新方法具有一系列独特的优点。本文作者提出了一种新颖的爆炸物检测方法,即(双能X射线) (前向散射法)。使用双能X射线法可以得到被检测物质的有效原子序数信息,利用X射线的前向散射可以得到被检测物质的密度信息,而有效原子序数和密度这两个特征量的组合就可以有效地表征爆炸物的存在。     

Measurement of tungsten impurity spectra with a two-crystal X-ray crystal spectrometer on EAST

Spectral measurement of tungsten (W) impurity is essential to study impurity transport. Therefore, an X-ray crystal spectrometer (XCS) on EAST was used to measure the line spectra from highly ionized W ions. On EAST, both poloidal XCS and tangential XCS have been developed to measure the plasma temperature as well as the rotation velocity. Recently, He-like and H-like argon spectra have also been obtained using a two-crystal setup. W lines are identified in this study. Through a careful analysis, the W lines of 3.9336, 3.9321, and 3.664 Å are found to be diffracted by He-like or H-like crystals. The lines are confirmed with the NIST database. We also calculated the ion temperature with Doppler broadening of these lines. The ion temperature from the W lines is entirely consistent with that from Ar line spectra. The measurement of these W line spectra could be used to study W impurity transport in future work.     

An evaluation of the influence of impurity concentration and composition in concrete on activation and radiation dosein the reactor facility

The content analysis of radioactive waste and radiation dose evaluation is considered as one of the important factors in the reactor facility design.This kind of buildings consists of the concrete for the most part and uses it as the structure and shield of the building.Generally,the concrete has impurities such as cobalt,europium,nickel,and cesium with specific content depending on the production method or manufacturing company.Dominant radioactive nuclides generated from the fundamental compon...