Quantitative Energy Dispersive X-ray Fluorescence Research Articles

Сарнилын пикийг ашигласан тулгуур параметрын арга

Instead of using the complete set of fundamental parameters for solving matrix effects in quantitative energy dispersive x-ray fluorescence analysis, some of them, such as excitation and detection efficiency and dependence of Compton and Reylaeigh scattered intensities on sample composition, were determined from a set of standards such as chemical compounds and pure elements. In this way all fundamental parameters except mass absorbtion coefficients were removed from the calculation procedure, which results in a much simpler formalism. the computer program based on this principle and described in this paper is relatively simple and, can run even on small computers, while the overall error can be kept in the range of few percent.

Influence of soil sample grain size on energy dispersive X-ray fluorescence analysis: a comparative study case with three spectrometers

This study aims at evaluating the particle size influence on the quantitative Energy Dispersive X-ray Fluorescence data of tropical soils, as well as evaluating the results trueness and precision using different statistical approaches. These objectives were conducted in three spectrometers, a benchtop one, and two portable ones. Certified reference materials were employed in calibration and trueness evaluation. Soil samples were collected, grounded and sieved in particle sizes: macerated (>2 mm), <2, <0.7, <0.3, <0.125, and <0.06 mm. The three spectrometers had different performances and lack of trueness for Potassium and Zinc in the Lab-made spectrometer. Regarding the grain size parameters, the spectrometers responded in different ways. It was identified that the best soil grain size condition for one of the portable spectrometers was <0.06 mm, while for the benchtop and for the other portable spectrometer the best soil grain size was <0.125 mm. In summary, the soil grain size affected the quantitative results in Energy Dispersive X-ray Fluorescence measurements, but it depends on the sensitivity of each spectrometer and the element of interest.

Quantitative energy-dispersive X-ray fluorescence analysis for unknown samples using full-spectrum least-squares regression

The full-spectrum least-squares (FSLS) method is introduced to perform quantitative energy-dispersive X-ray fluorescence analysis for unknown solid samples. Based on the conventional least-squares principle, this spectrum evaluation method is able to obtain the background-corrected and interference-free net peaks, which is significant for quantization analyses. A variety of analytical parameters and functions to describe the features of the fluorescence spectra of pure elements are used and established, such as the mass absorption coefficient, the $$G_{i}$$ factor, and fundamental fluorescence formulas. The FSLS iterative program was compiled in the C language. The content of each component should reach the convergence criterion at the end of the calculations. After a basic theory analysis and experimental preparation, 13 national standard soil samples were detected using a spectrometer to test the feasibility of using the algorithm. The results show that the calculated contents of Ti, Fe, Ni, Cu, and Zn have the same changing tendency as the corresponding standard content in the 13 reference samples. Accuracies of 0.35% and 14.03% are obtained, respectively, for Fe and Ti, whose standard concentrations are 8.82% and 0.578%, respectively. However, the calculated results of trace elements (only tens of μg/g) deviate from the standard values. This may be because of measurement accuracy and mutual effects between the elements.

Structural Aspects and Thermal Degradation Kinetics of Water Treatment Plant Sludge of Moroccan Capital

This paper reports a study on the structural characterization, structural transformations with temperature, and non-isothermal degradation kinetics of urban drinking water sludge. Chemical composition analysis by quantitative energy dispersive X-ray fluorescence suggests that the sludge is mainly inorganic in nature with small fraction of organic matter. Structural analysis of the sludge by SEM, XRD, and FTIR reveals structural complexities of the sludge. Thermal treatment of the sludge in the long temperature range shows that the sludge is capable of exhibiting different physico-chemical transitions. The reaction profile of the sludge thermal degradation is evaluated by TGA/DTG analysis which has been found considerably complex comprising many reactions. The thermal degradation kinetics is performed by thermoanalytical data of the sludge obtained by DSC using solid state kinetics approaches. The mechanistic information extracted from kinetic analysis fairly agrees with the structural analysis results. The present study reveals that the analyzed drinking water sludge has significant potential to be employed in the materials of construction.

Characterization of “oil on copper” paintings by energy dispersive X-ray fluorescence spectrometry

Energy dispersive X-ray fluorescence is a common analytical tool for layer thickness measurements in quality control processes in the coating industry, but there are scarce microanalytical applications in order to ascertain semi-quantitative or quantitative information of painted layers. "Oil on copper" painting becomes a suitable material to be analysed by means of X-ray fluorescence spectrometry, due to the metallic nature of substrate and the possibility of applying layered models as used in coating industry. The aim of this work is to study the suitability of a quantitative energy dispersive X-ray fluorescence methodology for the assessment of the areal distribution of pigments and the characterization of painting methods on such kind of pictorial artworks. The method was calibrated using standard reference materials: dried droplets of monoelemental standard solutions laid on a metallic plate of copper. As an example of application, we estimated pigment mass distribution of two "oil on copper" paintings from the sixteenth and eighteenth centuries. Pictorial layers have been complementarily analysed by X-ray diffraction. Apart of the supporting media made of copper or brass, we could identify two different superimposed layers: (a) a preparation layer mainly composed by white lead and (b) the pictorial layer of variable composition depending on the pigments used by the artist on small areas of the painting surface. The areal mass distribution of the different elements identified in the painting pigments (Ca, Cr, Mn, Fe, Zn, Cd, Hg and Pb) have been determined by elemental mapping of some parts of the artworks.

Quantitative EDXRF analysis of Ca, K, Mn and Na in normal and pathological adult-human teeth

This work relates to the measurement of calcium, potassium, manganese and sodium levels in adult-human teeth from female and male patients and normal subjects. Energy dispersive X-ray fluorescence (EDXRF) technique was used for the measurements. Pathological and non-pathological adult-human teeth samples were collected from one male human patient and one female human patient who attended the dental clinic. The standard addition method was used to determine concentrations. Experimental results are presented and discussed in this work.

F67 Development of a quantitative EDXRF method for determining the concentration of palladium applied to tobacco

A quantitative energy dispersive X-ray fluorescence (EDXRF) spectrometry method was developed for determining the concentration of palladium (Pd) applied to tobacco cut filler. Control and standards were created in-house with different levels of Pd concentration. After application of the Pd in a salt solution, the tobacco had an average oven volatiles (OV) value of 27.6%. Three aliquots were analyzed at each concentration level by EDXRF and inductively coupled plasma - atomic emission spectrometry (ICP-AES). Results were plotted against target values to perform a linear regression. EDXRF and ICP-AES coefficient of determination (R 2 ) values were both lower than the accepted minimum value of 0.990. Also, measured concentrations varied significantly between replicates. To improve the calibration technique, two options were evaluated: (a) Improve sample homogeneity by lyophilizing and finely grinding the tobacco, and (b) Improve the linear fit of the EDXRF calibration curve by plotting against ICPAES results. EDXRF and ICP-AES analyses were performed on lyophilized samples with an average OV value of 3.3%. Results demonstrated minimum variation between replicates and distinct variation between levels of concentration. Results were plotted against target values, and both EDXRF and ICP-AES R 2 values improved. For evaluation of option (b), EDXRF results were plotted against ICP-AES results to create the calibration curve with an R 2 value of 0.994. Compton scatter was implemented in the method to account for the difference in the moisture content of the lyophilized standards and the unknown samples with high OV values.

Iron electrodiffusion of bulk YBaCuO superconductor under different magnetic fields

In this study, diffusion mechanism of iron impurities in bulk YBa2Cu3O7 (YBaCuO) superconductor prepared by standart solid state reaction method and its effect on lattice structure under different magnetic field have been examined. Correlation between characteristic X-ray intensities and surface dopant density were investigated. The effects of different magnetic field intensities on crystal structure of iron diffused samples have been investigated by quantitative Energy Dispersive X-Ray Fluorescence (EDXRF) and X-ray Diffraction (XRD) techniques. It was found that Fe diffusion increases with increasing magnetic field.

Quantitative EDXRF Studies of Obsidian Sources in Northern Hokkaido

Quantitative trace element data from six obsidian sources on the Japanese island of Hokkaido is presented. Previous work by Japanese scholars has utilized neutron activation analysis (NAA) focusing on the rare earth elements, or qualitative energy dispersive X-ray fluorescence (EDXRF). In this study, non-destructive EDXRF is used to generate trace element data for 9 elements. Bivariate plots of the incompatible trace elements (Ba, Rb, Sr, Y, and Zr) can be used to separate the obsidian sources in this study. Source separation was confirmed by using linear discriminant analysis. Stepwise discriminant analysis indicates that Ba, Sr, Rb, Ti, Y, and Zr are the most discriminating elements.

Quantitative energy-dispersive x-ray fluorescence analysis of liquids using partial least-squares regression

Energy-dispersive x-ray fluorescence in combination with partial least-squares regression (PLSR) was used to determine nickel, copper and arsenic in aqueous solutions. Different spectrum pre-processing methods (square root and logarithmic transformation and top hat filtering) were used prior to the PLSR calibration. An accuracy of better than 5% was obtained. The effect of the Rayleigh and Compton scatter peaks and the continuum on the performance of the PLSR method was investigated. The PLSR method was compared with the method of Lucas-Tooth and Price and showed similar results. Copyright © 1999 John Wiley & Sons, Ltd.

The Monte Carlo—Library Least-Squares approach for energy-dispersive x-ray fluorescence analysis

A new analysis principle called Monte Carlo—Library Least-Squares (MCLLS) approach has been identified and investigated for quantitative energy dispersive x-ray fluorescence analyses. The feasibility of the MCLLS principle has been investigated with a radioisotope source excited EDXRF analytical system for several standard samples of known composition. With good initial elemental composition guesses, the MCLLS results showed excellent agreement with the elemental compositions in the standard samples. Furthermore, by taking the ratio of the photoelectric peak counts in the sample experimental spectra as approximate initial guesses, the proposed iterative MCLLS algorithm works quite well, converging to the correct elemental compositions. Only one iteration was needed for the analysis of all major elements. For trace elements a second iteration was needed in some cases. Other possible applications of the MCLLS approach and future work are also discussed.

General approach for quantitative energy dispersive x-ray fluorescence analysis based on fundamental parameters

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTGeneral approach for quantitative energy dispersive x-ray fluorescence analysis based on fundamental parametersFei. He and Pierre J. Van EspenCite this: Anal. Chem. 1991, 63, 20, 2237–2244Publication Date (Print):October 15, 1991Publication History Published online1 May 2002Published inissue 15 October 1991https://doi.org/10.1021/ac00020a009RIGHTS & PERMISSIONSArticle Views551Altmetric-Citations72LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (932 KB) Get e-Alerts Get e-Alerts

An integrated system for quantitative EDXRF analysis based on fundamental parameters

A procedure for quantitative energy-dispersive X-ray fluorescence analysis is presented. It relies on the fundamental parameter equation and optionally uses the intensity of the scattered excitation radiation to estimate the composition and mass per unit area of the low-atomic-number part of the matrix. The procedure has been implemented as part of a larger software package, AXIL-QXAS, which includes spectrum-acquisition and spectrum-analysis programs and runs on a personal computer.

GEOXRF: quantitative analysis program for energy dispersive x-ray fluorescence analysis

A FORTRAN-77 program. GEOXRF, is described for quantitative energy dispersive X-ray fluorescence analysis. The program employs the fundamental parameter method for quantitative analysis and corrects for absorption of X-rays, the result of interelement effects, by iteration. To reduce computer storage requirements, parameterized equations for mass absorption coefficients, emission-line energies and absorption-edge energies are utilized. The program is designed to be used in stand alone mode.

Trace element distributions of a granular activated carbon

Elemental distributions obtained by energy dispersive X-ray fluorescence (EDXRF) analysis, combined with scanning electron microscopy (SEM), are presented for used and virgin samples of a commercial granular activated carbon (GAC) Calgon F400 manufactured from bituminous coal. Distributions of Al, Si, K and Fe reveal the presence of large inclusions of a clay mineral such as illite, approximately 10–360 μm in diameter. We also find mineral inclusions of Fe alone, about 6–80 μm in diameter. The elemental distributions for S are diffuse and do not indicate the presence of iron sulfide compounds, although pyrite is the major iron mineral in bituminous coal feedstocks used for Calgon F400. The Mössbauer spectrum of Calgon F400 confirms the presence of iron oxides and iron metal, as probable products of pyrite during manufacture of the GAC. In samples of F400 used for potable water purification, Cl and Ca are characterized by diffuse distributions; results of quantitative EDXRF analysis indicate these elements are associated with compounds adsorbed from water on the surface of Calgon F400.

Application of a fundamental parameter technique for solving peak-overlap problems in quantitative energy-dispersive x-ray fluorescence spectrometry

The procedure exploits the fundamental parameter technique for monoenergetic excitation. The algorithm describes each peak as a sum of line intensities, thus intensities from unresolved lines are included directly in the equations. The procedure includes the condition that the sum of all weight fractions equals unity, and so is valid only when all elements are measured by x-ray fluorescence spectrometry, e.g., in steel alloys. The procedure is tested with a set of theoretically calculated x-ray fluorescence intensities, and for two NBS standard steel alloys.