质子激发X射线分析法

质子激发X射线分析(Proton Induced X-ray Analysis简称PIXA,有时称为Proton Induced X-ray Emission质子诱导X射线发射)。PIXA技术是用高能质子轰击样品,用波长色散或能量色散谱仪分析被测物质的原子发射特征的X射线,从而分析样品的元素成分和含量。它对试样几乎没有损伤。     

能量色散X射线荧光能谱仪(EDXRF)在油液分析中的应用

本文在简要介绍X射线荧光能谱分析技术的基础上,以ThermoFisher公司生产的QUANT’X射线荧光能谱仪为例,介绍其在油液分析中的应用研究,并与原子发射光谱进行比较,分析X射线荧光能谱分析技术在应用于油液分析中的优势和不足,并提出相应的解决办法。     

掠出射微区X射线荧光分析系统的建立及其在薄膜分析中的应用

介绍了一种综合导管X光透镜及全反射X射线荧光分析技术的掠出射微区X射线荧光分析方法,并将其应用北京师范大学低能核物理研究所离子束物理与技术教研室采用MEVVA源离子束和薄膜沉积技术制备的纳米金属单层纳米薄膜及纳米多层膜的分析。实验中所用X光透镜的焦斑大小为41.7μm。通过对薄膜样品的掠出射角度扫描分析,可得到薄膜特征X射线的掠出射角分布曲线,通过将实验曲线与理论模拟曲线进行拟合,可得到薄膜样品在微小区域的厚度及密度。结果表明,相比于通过薄膜沉积过程中的离子电量估计的薄膜厚度值,该方法测出的薄膜厚度更接近于薄膜的实际厚度。同时结果表明,使用MEVVA离子束薄膜沉积技术所镀薄膜的密度均小于体材料样品的密度值,且薄膜厚度的增加,薄膜密度逐渐增大并接近于体材料的密度值。另外,通过对薄膜样品表面进行二维扫描分析,实验中,扫描步长为50μm,扫描区域为500μm*500μm,可分析薄膜表面微小区域的均匀性。     

X射线荧光光谱分析的新进展

本文简要介绍伦琴发现X射线100年后(1895～)X射线荧光光谱分析的新进展。随着各种新型探测器Si-PIN、SDD、超导隧道结、微热量计,各种新型激发源从微型X射线管到同步辐射无电子X射线激光及各种新型光学器件(Capillary)的出现,在世纪之交这一阶段X射线荧光光谱分析技术空前地扩展了其应用领域和应用能力。微区分析已可探测到原子数量级,X射线全息术和X射线断层术已可识别单晶中的原子分布和单个生物细胞的图像。预计在新的世纪里X射线荧光光谱技术必将又更加飞速的发展。     

能量色散X射线荧光光谱仪的现状

能量色散X射线荧光光谱分析以其快速、对试样无损、可以同时测定多种元素等优点,在许多领域中发挥巨大的作用。本文介绍能量色散X射线荧光光谱仪的原理和构造,并就目前仪器的研究现状和应用现状做介绍,指出X射线荧光分析技术的良好前景及进一步研究该仪器的必要性。     

北京安科慧生科技有限公司成功研制新型X射线荧光光谱仪

X射线荧光光谱仪,是土壤中重金属元素分析的手段之一,而其中的双曲面弯晶,又是X射线荧光光谱仪性能提升的关键技术,但该技术长期被美国一家分析仪器公司掌握和封锁。为此,北京安科慧生科技有限公司自2015年开始进行科研攻关,如今,已成功研制出X射线荧光光谱仪的核心部件--全聚焦型双曲面弯晶,成为世界上第二家拥有此项技术的公司,并依据这项核心技术,成功研制出便携式X射线荧光光谱仪,可用于土壤重金属污染限值检测。     

PIXE分析技术及其应用

介绍了质子激发的特征X射线能谱分析(PIXE)技术及其在环境科学、生物医学和考古等领域的应用。     

掠出射X射线荧光光谱仪研制

掠出射X射线荧光分析技术是分析薄膜特性和介质表面的一种重要工具.文中简述了利用掠出射X射线荧光技术分析薄膜厚度的原理和方法,介绍了一种在实验室里由激发光源、样品承载系统、色散系统、探测系统和数据收集及处理系统构成的掠出射X射线荧光光谱仪系统,并给出了利用⁵⁵Fe放射性同位素标定该光谱仪系统的试验结果.     

X射线荧光光谱技术在药品检测中的应用

X射线荧光光谱技术被广泛应用于药品检测,主要用于药品的元素成分分析以及鉴定评价和质量控制,本文对近年来X射线荧光光谱在药品检测方面的应用进行了综述。     

ARL9900X射线荧光光谱仪SC探测器故障处理

赛默飞世尔ARL9900X射线荧光光谱仪日常分析时,会出现TFe元素无成分,其它元素成分正常的现象.本文解析了X射线荧光光谱仪的工作原理,运用角度扫描和能量描迹的方法进行故障分析,确定SC探测器故障,并进行更换处理,再结合SC探测器工作原理及结构,对故障产生原因进行了探讨,总结使用维护经验.     

X-ray probe microanalyses and scanning x-ray microscopies

The analytical techniques based on excitation of inner-shell electrons by an incident X-ray photon beam suffer generally from their poor degree of lateral localization. Nevertheless it is possible to perform the microanalysis of a sample in the forms of a thin film by: (i) X-ray photoelectron spectroscopy (XPS or ESCA) and X-ray-induced Auger electron spectroscopy (XAES) for surface analysis; (ii) X-ray absorption spectroscopy (XAS) and X-ray microfluorescence spectroscopy (XMS) for bulk analysis. The corresponding images can also be obtained in the scanning mode: scanning X-ray photoelectron microscopy (SXPM), scanning X-ray-induced Auger electron microscopy (SXAEM) and scanning X-ray microradiography (SXM). The experimental arrangement and the results obtained are described here, together with further improvements and comparisons with other technical solutions.     

仪器分析在甲壳素与壳聚糖及其衍生物中的应用

综述红外光谱、紫外光谱、核磁共振、质谱、扫描电镜、X射线衍射在甲壳素与壳聚糖及其衍生物的官能团、结构、形貌等研究中的应用,并对仪器分析在甲壳素与壳聚糖及其衍生物中的应用和发展前景进行展望。     

现代分析技术在中药质量控制中的应用

介绍色谱法、光谱法、核磁共振波谱、质谱及其联用技术、DNA分子诊断技术、X射线衍射法等几种现代分析方法在中药质量控制中的应用。     

Fabrication of a Cr thin-film AEM characterization standard

The need for an analytical electron microscope (AEM) characterization standard capable of determining the consistency and relative quality of analytical performance has become increasingly evident as advances in the instrumentation are made. In this paper the fabrication of a Cr thin-film AEM standard by conventional thermal evaporation techniques is described. A 100-nm-thick Cr film on a 20-nm C-support film provided by the National Institute of Standards and Technology (NIST) served as a model against which the present film was evaluated. Improvements over the NIST film in terms of diffraction pattern clarity and simplification of parallel electron energy-loss spectrometry (PEELS) analysis were achieved by removal of the C-support film and the creation of a self-supported Cr (SS-Cr) film. Qualitative grain-size comparisons between the NIST model and the SS-Cr films made by scanning transmission electron microscopy found the SS-Cr films to have a slightly larger grain size. Thickness measurements were verified by X-ray energy dispersive spectrometry, PEELS and field-emission gun scanning electron microscopy. SS-Cr film standard specimens are available for use by the AEM community, by contacting the authors directly.     

Failure Analysis and Condition Monitoring of an Open-Loop Oil System Using Ferrography

Condition monitoring of dynamic systems based on oil analysis is well known for closed-loop systems. The motivation for this work stemmed from repeating failures of Wankel engines. Failure analysis identified contact fatigue as the failure mechanism, but could not identify the cause. Thus, the objective of the work was to develop a method for condition monitoring of open-loop oil systems. A variety of analytical techniques was evaluated, including direct-reading ferrography, analytical ferrography combined with computational image analysis, atomic emission spectroscopy, and scanning electron microscopy combined with energy dispersive X-ray spectroscopy. Procedures for collection and separation of oil samples were developed. Analytical ferrography was found most useful in condition monitoring. Six engines were detected in their early failure stage. Those engines were disassembled, and contact fatigue failures in the bearing needles were observed. The quantitative image analysis allowed for a fairly objective rating of the wear level. The method developed in this work has already been implemented on a daily basis for monitoring the health of Wankel engines, with much success.     

软X射线显微术和光谱显微术

X射线显微术可直接在水环境中对胶体颗粒尺寸范围内的颗粒进行高分辨率成像,将该项技术与高分辨率光谱相结合,还可用于光谱显微研究。其中,常用的两种X射线显微镜是透射显微镜和扫描透射显微镜,文中示出了它们的装置图。由于X射线显微镜能迅速拍下一物体的高分辨率图像,所以,作为一种分析仪器,扫描X射线显微镜更适合作光谱显微研究。作为形态学目视化的一个示例,本文用一台透射X射线显微镜拍摄了粘土和土壤样品的图像。根据X射线图像进行的低温层析实验所获得的图像得到了有关细菌构成的显微生存环境以及其它土壤胶状体的3D结构信息。对扫描透射X射线显微镜拍摄的一系列图像进行分析,得到了土壤样品的形貌特性和化学特性。     

Steelmaking in India – new evidence from microscopic and archaeometallurgical analysis from middle Ganga plain,Balirajgarh

The present study deliberates on the archaeometallurgical examination of 2300 years old excavated iron nail from India's middle Ganga plain of Balirajgarh. The nail was subjected to multianalytical investigations in order to determine the raw materials used, manufacturing technology and preservation state. The combined analytical techniques optical microscopy, scanning electron microscopy-energy dispersive X-ray spectrometry (SEM-EDX), Vickers hardness and X-ray diffractometry shed light towards the characterisation and use of the iron artefact. Special attention was paid for qualitative and quantitative analysis of slag inclusions, metal matrix and corrosion products. The presence of heterogeneous microstructure and inclusion of impurities suggests that nail has been produced through the direct process and work hardened. The noncorroded nail is made of hypereutectoid steel and used for building purpose. The study is important to understand the role of technology in the evolution of cultural changes in India that also provides archaeometric data on the method used in the forging work.     

Electronic core level microanalyses and microscopies in multipurpose apparatus

Using an instrument equipped with two electron guns, an electron analyzer, and a Si(Li) diode detector, we developed microanalytical techniques based on inner-shell electron excitations by incident electrons and X-rays, that is, electron energy-loss spectroscopy (EELS) in the reflection mode; electron probe microanalysis (EPMA) and X-ray appearance potential spectroscopy (XAPS); electron-induced Auger electron spectroscopy (e-AES); X-ray photoelectron spectroscopy (XPS), X-ray absorption spectroscopy (XAS); X-ray induced AES (XAES), X-ray fluorescence analysis (XRF), and scanning X-ray radiography (SXR). The corresponding characteristic images (including X-ray microradiography and X-ray photoelectron microscopy) were obtained in the scanning mode. The principle of the apparatus is described. Each spectroscopy and microscopy is illustrated by an example. Their performance and limits are discussed.     

High spatial resolution spectroscopy in the elemental microanalysis and imaging of biological systems

The application of analytical electron microscopy to the high spatial resolution study of biological systems is reviewed. Specimen preparation, quantitative analysis, capabilities and limitations are all discussed, principally in the context of energy-dispersive X-ray analysis. Results are presented using both current techniques and the developing quantitative image analysis. Finally the role of new instrumental approaches, including electron energy loss spectrometry, is discussed.     

Low-temperature scanning electron microscopy of particle-exposed mouse lung

Inflated frozen mouse lungs were examined using low-temperature scanning electron microscopy (LTSEM) following bulk fracture under vacuum. Various aspects of pulmonary architecture were identified and correlated with structures revealed by SEM following conventional fixation and preparation techniques. Surface etching of selected samples was performed by radiant heating, revealing characteristic cytoplasmic, nuclear and extracellular lattice patterns resulting from ice crystal formation during freezing. These patterns aided in distinguishing between intra- and extracellular spaces. Pulmonary fluids such as mucus and surfactant were identified. Iron oxide particles were introduced into the lungs of some animals by intratracheal instillation and were subsequently identified in frozen-hydrated lung tissue using characteristic X-ray identification and mapping techniques. Particles were observed both intra-and extracellularly and were commonly found in large deposits. These observations confirm the utility of LTSEM techniques for examination of particles within pulmonary tissue. Particle exposure by intratracheal instillation was found to result in a non-uniform distributional pattern.