Identification of steel by X-ray fluorescence analysis with a pyroelectric X-ray generator

An application of X-ray fluorescence analysis with a pyroelectric X-ray generator is presented. Steel standard samples were identified by X-ray fluorescence analysis with this novel X-ray generator to check its capability for performing qualitative and quantitative analysis as an X-ray source for X-ray fluorescence spectrometers. Cr, Ni, V, Co, and W were detected in steel standard samples. V and Cr can be detected even when the content is below 1%. Although it is difficult to detect minor elements because of the low power of the excitation X-rays, it is possible to identify the analyzed samples on the basis of major elements at the percentage level. The pyroelectric X-ray generator is very suitable for portable X-ray fluorescence spectrometers.     

An X-ray fluorescence spectrometer with a pyroelectric X-ray generator and a secondary target for the determination of Cr in steel

An X-ray fluorescence (XRF) setup with a pyroelectric X-ray generator and a secondary target for the determination of Cr in steel is presented. The pyroelectric X-ray generator, which can be driven by a dry battery, is a low power X-ray source and emits X-rays over a large solid angle. X-rays emitted by this generator can be effectively put to use by a disk-shaped secondary target. An appropriate arrangement of (i) X-ray generator, (ii) sample support, (iii) secondary target, and (iv) detector enables secondary X-rays to irradiate the sample from a short distance. The secondary X-rays are emitted from a wide-area secondary target. The present arrangement also enables the sample to be placed near the detector. The short distance from the sample to both the secondary target and the detector enhances signal intensity. An absolute amount of 1.3 μg Cr can be detected by the present setup. A minimum detection limit of 0.09 wt.% Cr in steel by 1000-s measurement has been achieved.     

Trends,applications and results in X-ray fluorescence analysis

X-ray fluorescence (XRF) has reached a mature state and represents a powerful analytical tool for the qualitative and quantitative determination of almost all the chemical elements in a sample. Standard XRF methods as well as special techniques to improve the detection limits will be presented, emphasizing the versatility of the method. With modern instrumentation the detectable number of elements ranges from Be to U. The minimum detectable quantities under optimizied excitation and detection conditions for medium Z elements are a few hundred femtograms. Other features like rapid analysis because of the multielement capability and in some cases the nondestruction of the sample are advantageous for a wide field of applications.     

Determination of Sr,Zn, Cu and Fe in Licorice by X-ray Fluorescence Spectrometry

Few persons determine the trace elements in the licorice by X-ray fluorescence spectrometry (XRF), because there is no standard samples of the licorice. This paper describes the method to determine Sr,Zn,Cu and Fe in licorice using XRF. The samples are ashed and then determined with the powder process. The measured results are corrected by artificial standard samples.     

Preparation and characterization of polymer layer systems for validation of 3D Micro X-ray fluorescence spectroscopy

For the validation of the quantification of the newly-developed method of 3D Micro X-ray fluorescence spectroscopy (3D Micro-XRF) samples with a low average Z matrix and minor high Z elements are best suited. In a light matrix the interferences by matrix effects are minimized so that organic polymers are appropriate as basis for analytes which are more easily detected by X-ray fluorescence spectroscopy.     

Analytical possibilities of different X-ray fluorescence systems for determination of trace elements in aqueous samples pre-concentrated with carbon nanotubes

This study was aimed to achieve improved instrumental sensitivity and detection limits for multielement determination of V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Se, Pb and Cd in liquid samples by using different X-ray fluorescence (XRF) configurations (a benchtop energy-dispersive X-ray fluorescence spectrometer, a benchtop polarised energy-dispersive X-ray fluorescence spectrometer and a wavelength-dispersive X-ray fluorescence spectrometer).The preconcentration of metals from liquid solutions consisted on a solid-phase extraction using carbon nanotubes (CNTs) as solid sorbents. After the extraction step, the aqueous sample was filtered and CNTs with the absorbed elements were collected onto a filter paper which was directly analyzed by XRF.The calculated detection limits in all cases were in the low ng mL^− 1 range. Nevertheless, results obtained indicate the benefits, in terms of sensitivity, of using polarized X-ray sources using different secondary targets in comparison to conventional XRF systems, above all if Cd determination is required.The developed methodologies, using the aforementioned equipments, have been applied for multielement determination in water samples from an industrial area of Poland.     

Analysis of non-organic elements in plant foliage using polarised X-ray fluorescence spectrometry

An X-ray fluorescence (XRF) method for the rapid and non-destructive analysis of 30 non-organic elements in plant leaves over five orders of magnitude concentration from several percentage of dry weight to sub-milligram per kilogram, is described. There is a growing need for a simple method of monitoring non-organic trace elements in plant material, especially those which accumulate in soils with application of fertilisers, both inorganic and biosolids. Earlier attempts to use XRF for the analysis of plant material suffered from sensitivity loss due to the high background of organic matrices caused by scattering of the X-ray source. We overcome this by using polarised X-ray sources in a Cartesian geometrical arrangement with sample and energy dispersive detector (EDPXRF), a configuration which can achieve an order of magnitude reduction in background compared with unpolarised sources. Further sensitivity gains are made using a high power tube as a source of primary X-rays and for some analytes employing secondary targets for near-monochromatic excitation. Sample preparation is simple involving only pulverising and briquetting of dried samples. Accuracy is evaluated by comparing data obtained for the suite of NIST plant leaf samples (NIST 1515 apple leaves, NIST 1547 peach leaves, NIST 1570a spinach leaves, NIST 1573a tomato leaves and NIST 1575a pine needles) and tobacco leaf standards CTA-OTL-1 and CTA-VTL-2. The data compare well over the whole concentration range and the method provides a rapid analytical tool for monitoring potentially toxic trace elements in all types of foliage with adequate sensitivity for many purposes.     

Study on deposition kinetics of high-K materials by X-ray fluorescence techniques

X-ray fluorescence (XRF) techniques have been used to study, on different pretreated substrates, deposition kinetics of HfO₂ and Al₂O₃, two of the possible high-K materials under evaluation for future integration in microelectronic devices.X-ray fluorescence (XRF) and total X-ray fluorescence (TXRF) measurements demonstrate their capability to give useful information on the very initial growing cycles of deposition and on carbon and chlorine inclusion in the film. Moreover, XRF signal shows a good linear correlation with layer thickness for thick samples of both materials.     

Spatially resolved X-ray fluorescence analysis with a pyroelectric X-ray emitter.

A portable instrument for two-dimensional X-ray fluorescence imaging was assembled with an X-ray source using a pyroelectric crystal, which was driven by a 9-V dry battery, a Si-PIN detector, a slit, and pulse motors. Line scanning for a mug and a knife-edge-scan of an iron sheet were carried out using this spectrometer. The sensitivity of the spectrometer was sufficient for elemental analysis of a mug using a 1 mm(2) slit, and several elements, such as Co, Ni, Zn, Pb and Zr, were detected. The estimated spatial resolution using a 0.8-mm pinhole was 3.5 mm.     

X射线荧光光谱法结合多元统计学对热敏纸的检验研究

为建立一种快速且无损检验热敏纸的科学有效的方法,利用能量色散型X射线荧光光谱(XRF)对38个不同商家,不同规格的热敏纸样品进行检验,首先根据每个样品所测量得到的元素的不同,将38个样品分成四大类,同时采用SPSS25.0软件中的系统聚类法对38个样品的元素数据进行聚类分析处理,结果分成了12小组,再结合SPSS25.0软件中的判别分析法对上述结果进行验证,实现了基于X射线荧光光谱结合聚类分析建立数学模型用于区分热敏纸种类的目的,该方法简单易行,可以为案件侦破提供线索、指明方向。     

X-ray fluorescence analysis of polymetallic ores

An analytical procedure for determination of Fe, Ti, V, Ni, Co and Cu, the most important constituents of the polymetallic ore has been developed. Twenty four powdered samples were prepared from the material taken in various places of the ore deposit. The samples were analyzed by wavelength dispersive (WD) and energy dispersive (ED) XRF method. The EDXRF method was applied using radioisotope source as well as a low power X-ray tube (Rh-anode) for excitation of the characteristic K-line radiation of the elements. A Si(Li) detector was used for the detection of radiation. The detection limits and precision of the analytical procedures, using reference materials, were estimated. The accuracy of the different XRF techniques is discussed. The developed analytical procedures based on the XRF method are rapid and quite simple. They can be useful for exploration data accumulation.     

The influence of scattering processes in quantitative X-ray fluorescence analysis

Existing theory was used to develop a fundamental parameter (FP) computer program for quantitative X-ray fluorescence (XRF) spectrometry in which scattering interactions are taken into account. The program is suited for polychromatic radiation and composite samples and is used to estimate the errors that result from neglecting the scattering contributions in the analysis of samples in a low Z matrix when the spectrometer is calibrated either on pure elements or on standards similar to the samples.     

Major element analysis of selected rock and volcanic ash samples in the Unzen area,Japan, by X-ray fluorescence spectroscopy

Determination of major elements in natural solid samples by X-ray fluorescence spectroscopy (XRF) with a fusion disc technique is described. Data obtained by the present XRF analytical system were found to have satisfactorily high reliability. Five rock samples and a volcanic ash sample with varying ages ranging from the present to 180 000 years, derived by the current and past volcanic activities in the Unzen area, Nagasaki, Japan were analyzed for their major elements' compositions using the above mentioned system. The chemical composition of the magma under this area has changed very little at least over the last 180 000 years.     

A new atomic database for X-ray spectroscopic calculations

The authors undertook to compile a database of recent values of the atomic parameters required for fundamental parameters (FP) calculation of X-ray fluorescence (XRF) spectra, calculation of X-ray absorption in crystals and other samples, and correction of X-ray absorption spectra for self-absorption effects. All values were obtained from published sources and include the elements hydrogen (atomic number 1) through californium (atomic number 98). The data were collected into a single unstructured ASCII text file.     

Trends in hard X-ray fluorescence mapping: environmental applications in the age of fast detectors

Environmental samples are extremely diverse but share a tendency for heterogeneity and complexity. This heterogeneity poses methodological challenges when investigating biogeochemical processes. In recent years, the development of analytical tools capable of probing element distribution and speciation at the microscale have allowed this challenge to be addressed. Of these available tools, laterally resolved synchrotron techniques such as X-ray fluorescence mapping are key methods for the in situ investigation of micronutrients and inorganic contaminants in environmental samples. This article demonstrates how recent advances in X-ray fluorescence detector technology are bringing new possibilities to environmental research. Fast detectors are helping to circumvent major issues such as X-ray beam damage of hydrated samples, as dwell times during scanning are reduced. They are also helping to reduce temporal beamtime requirements, making particularly time-consuming techniques such as micro X-ray fluorescence (μXRF) tomography increasingly feasible. This article focuses on μXRF mapping of nutrients and metalloids in environmental samples, and suggests that the current divide between mapping and speciation techniques will be increasingly blurred by the development of combined approaches.     

X射线荧光光谱熔融法测定锶永磁铁氧体中各组分含量

本文使用自制标准样品,采用混合熔剂熔融样品,用X射线荧光光谱法(XRF)测定锶永磁铁氧体半成品中Fe,Sr,Si等元素的含量.熔融制样有效地消除了矿物效应,并降低了基体效应的影响.实验结果表明,本法准确度高,重现性好,平行测定11次相对标准偏差(RSD)可达到0.1%.该方法用于实际样品分析,其结果与传统化学分析方法结...     

Use of portable X-ray fluorescence instrument for bulk alloy analysis on low corroded indoor bronzes

One of the most often used non-destructive methods for elemental analysis when performing field measurements on bronze sculptures is X-ray fluorescence (XRF) analysis based on portable instrumentation. However, when performing routine in-situ XRF analysis on corroded objects obtained results are sometimes considerably influenced by the corrosion surface products.In this work the suitability of portable XRF for bulk analysis of low corroded bronzes, which were initially precisely characterized using sophisticated and reliable laboratory methods, was investigated and some improvements in measuring technique and data processing were given. Artificially corroded bronze samples were analyzed by a portable XRF instrument using the same methodology and procedures as when performing in-situ analysis on real objects. The samples were first investigated using sophisticated complementary laboratory techniques: Scanning Electron Microscopy, Proton-Induced X-ray Emission Spectroscopy and Rutherford Backscattering Spectrometry, in order to gain precise information on the formation of the corrosion product layers and in-depth elemental profile of corrosion layers for different aging parameters. It has been shown that for corrosion layers of up to ca. 25 μm a portable XRF can yield very accurate quantification results.     

Determination of metallic impurities in U3O8 using energy dispersive X-ray fluorescence spectrometry

In order to examine the capability of energy dispersive X-ray fluorescence spectrometry for the determination of some common metallic impurities in nuclear grade U₃O₈ matrix, a series of synthetic U₃O₈ standards, containing impurities such as Ca, Co, Cr, Cu, Fe, Mn, Mo, Ni ,V, W and Zn in the concentration range, 100–1000 μg/g, were prepared. Using these standards, calibration curves were set up for different elements after optimizing the spectrometer parameters. Two synthetic samples and five reference standards obtained through an inter-laboratory comparison exercise within analytical laboratories of Department of Atomic Energy, India were analyzed to evaluate the performance of the newly developed analytical methods. The estimates for most of the analytes were in good agreement with the added amounts. The method is fast, since it requires no chemical treatment. The method has good precision for the analytes determined.     

X射线荧光光光谱分析

评述了我国在2007～2008年X射线荧光光谱,包括质子激发的X射线光谱的发展和应用,内容包括仪器、软件、仪器改造、仪器维护和维修、基础研究和分析方法研究及其应用.