bluuebunny/crossref_metadata_2025_split huggingface dataset:
An X‐ray narrow band detector and its application to X‐ray spectral quantitative analysis
Authors: Anisovich K. V. , Komyak N. I. 
Published: May 2005

AbstractAn X‐ray narrow band detector based upon a selective X‐ray filter and selective secondary emitter is described. The detector transmission band makes up 0.3–1.5 Ke Vin the range 2–40 KeV. The detection efficiency of X‐rays reaches 5%, the area of the detector entrance window being 10cm2.A high luminosity of the narrow band detector makes it possible to decrease the required power of an X‐ray tube to a few watts in X‐ray spectral quantitive analysis. optimal relations between the detector elements as well as optimal conditions of fluorescence excitation are discussed. The application of the narrow band detector to X‐ray spectral quantitative analysis is illustrated.
Use of a bare CaF2 (Eu) scintillator to assess the escape peak formalism and the fundamental parameter method
Authors: Szöghy I. M. 
Published: May 2005

AbstractEscape peak and thick target yield formalisms are shown to be equivalent, although experimental results using a practical source–target–detector geometry favor the latter. A bare non‐hygroscopic CaF2(Eu) scintillator is used to measure the K X‐ray yield from thick targets of pure elements excited by monoenergetic photons. The scintillator is found free of dead layer up to the limit of 0.1 μm: it can thus detect photons above 2 keV energy with intrinsic efficiency approaching 100%.
A microcomputer based control and data acquisition system for early model wavelength‐dispersive X‐ray fluorescence spectrometers
Authors: Jablonski Bruce B. , Leyden Donald E. 
Published: May 2005

AbstractEarly model wavelength‐dispersive X‐ray fluorescence spectrometers can be inexpensively fitted with computer capability through the use of a microcomputer. The principal advantage of the microcomputer over a minicomputer is low cost and the principal disadvantage is relatively slow computational speed. We have found that an Apple II plus microcomputer can perform all of the tasks previously assigned to a larger (and more expensive) minicomputer. Ready availability, ease of service and program flexibility make the microcomputer an attractive choice for a laboratory computer. A matrix effect correction program, XRF‐4, has been run in the microcomputer with excellent results.
Theoretical evaluation of overlap coefficients in XRF spectra
Authors: Datta S. , Sadasivan S. 
Published: May 2005

AbstractAn attempt has been made to obtain theoretically the overlap coefficients of interfering lines in XRF spectra. The peaks have been analytically represented by a Gaussian function and the overlap evaluated for Covell integration. The coefficients for a wide range of elements and for various detector resolutions have been computed as a function of integration window width. The variation with window width of evaluated coefficients is compared with published experimental values.
A simple method for calculating x‐ray absorption spectra for use in crystal spectrometer and mirror analysis
Authors: Shah A. , Gurman S. J. 
Published: May 2005

AbstractA simple scheme is described whereby x‐ray absorption spectra, including the very strong rapidly varying structure near an absorption edge, may be calculated using only a short program and small amounts of computer time. The analysis also provides general rules for the existence of strong structures at the edge. The scheme can describe any neutral absorbing atom (or, with a little modification, ion) and includes the effect of the core hole when necessary. Fits to experiment show good agreement near absorption edges, with somewhat poorer agreement far from the edge. The method is of use in obtaining absorption spectra for use in crystal spectrometers for x‐ray mirror calculations where a knowledge of the fine detail of the absorption is not necessary, but an accurate reproduction of the major structure near the edge is.
Simultaneous multielement analysis of phosphates by x‐ray fluorescence
Authors: Issahary D. , Pelly I. 
Published: May 2005

AbstractAn accurate, rapid and relatively cheap method adapted for use in the phosphate industry for on‐line simultaneous multielement analysis of phosphate ore and calcined phosphate, using x‐ray fluorescence, is described. The method of analysis is sufficiently accurate for the phosphate industry, which demands great accuracy in P2O5 analysis. A statistical evaluation of precision and accuracy is given.
Energy dispersive x‐ray diffractometry: 1. The specimen transparency factor
Authors: Mantler M. 
Published: May 2005

AbstractThe shape of energy dispersive diffraction lines from flat powder samples is determined by the Bragg angle, beam divergences, absorption of the radiation, specimen misalignment and detector performance. Due to asymmetric line broadening, the lines appear to be shifted, usually to lower energies. Two ‘specimen transparency models’ are presented, based upon the accurate determination of line positions and line intensities that are possible.
Relative intensity factors for K, L and M shell x‐ray lines
Authors: Schreiber T. P. , Wims A. M. 
Published: May 2005

AbstractAccurate values for x‐ray relative intensity factors, which are the fraction of intensity measured, are important for quantitative calculation procedures used in scanning transmission electron microscope thin film x‐ray microanalysis. We have developed equations for calculating these parameters for the K, L and M shells and have applied them to a thin film quantitative analysis procedure. The K shell values were obtained from experimental and theoretical data in the literature and show a constant region between atomic numbers 20 and 30. To obtain L shell values measurements were made with an electron probe and an energy dispersive system on a 200 kV scanning transmission electron microscope. These data were combined with values calculated from Coster‐Kronig and fluorescence yield data in the literature. The result was two curves with a step at atom number 51 and a significantly different magnitude than values used in other thin film methods. The following equations for use in a computer program were developed from these curves; aLα1.2(Z=27−50)=1.617−0.0398Z+3.766 × 10−4Z2; aLα1,2(Z=51−92)=0.609−1.619 × 10−3Z−0.03248 sin [0.161(Z−51)].
Comparison of the intensity correction method and the analytical value correction method in the correction of interfering spectrum overlap
Authors: Ito Minao , Sato Shoki , Narita Masanao 
Published: May 2005

AbstractIn the X‐ray fluorescence analysis of steels, a correction method is usually used so as to eliminate interfering spectrum overlap and absorption–enhancement effects. In correcting the former, the intensity correction method, by which measured x‐ray intensity is corrected, is widely used. In the JIS method of x‐ray fluorescence analysis of steels, however, the measured x‐ray intensity is first converted into a tentative analytical value, and this value is then corrected for absorption–enhancement effects and finally for interfering spectrum overlap. In this report, a detailed comparison of both methods is made, and the characteristics of the JIS method are discussed.
X‐ray fluorescence analysis of silver and palladium film thicknesses on silicon solar cells
Authors: Artz B. E. , Bomback J. L. 
Published: May 2005

AbstractAn x‐ray fluorescence technique was developed to analyze the thickness of Ag and Pd metallization layers on the back side contacts of Si solar cells. The technique employed a Sn secondary target x‐ray source excited by a Cr target x‐ray tube. Sn Kβ excited Ag Kα in the overlying Ag contact while Sn Kα and Kβ excited Pd Kα in the underlying Pd film. The emitted Ag and Pd Kα intensities were compared with corresponding intensities emitted from pure bulk Ag and Pd standards. Attenuation of Sn Kβ and Sn, Ag and Pd Kα in the Ag contact and in the standards was accounted for in the calculations. The results on 17 cells compared favorably with neutron activation analyses. An accuracy of ±10% was estimated for a 40 nm Pd film beneath a 7 μm Ag contact. Palladium films as thin as 1.5 nm were analyzed. The technique is nondestructive and can be applied to process control in a production environment as well as to laboratory testing of experimental cells.
Influence of interelement effects on x‐ray fluorescence calibration curve coefficients for binary mixtures
Authors: Mainardi R. T. , Fernández J. E. , Nores M. 
Published: May 2005

AbstractIt has been shown that x‐ray fluorescence calibration curve coefficients are closely related to matrix effects, such as absorption or absorption plus enhancement of the fluorescent radiation. In the classical paper of Rasberry and Heinrich,1 a single coefficient (named Aik) calibration curve was proposed when pure absorption is the predominant effect on the spectral line of interest. Similarly, and for practical purposes, a single coefficient (named Bik) was also considered when absorption and enhancement are present. We propose a new interpretation of calibration curve coefficients based on analytical expressions obtained recently for binary compounds under monochromatic excitation. Six distinct possible cases of calibration curves arise. Examples of binary compounds for each case are given. The data considered have been computed using the fundamental parameters method which allowed us to study a large number of possible mixtures for an arbitrary monochromatic excitation. Finally, through a different approach we discuss how this analysis could be extended to consider polychromatic excitation.
Automated qualitative wavelength‐dispersive x‐ray fluorescence analysis
Authors: Platbrood G. , Serbruyns M. , Quitin J. M. 
Published: May 2005

AbstractA SRSO1 Siemens x‐ray spectrometer equipped with a logical controller was controlled by a Tektronix 4051 computer to record step by step the x‐ray fluorescence intensities. Ten samples can be analysed after the recording of 2 spectra (LiF (110) and PET) for each sample on a magnetic tape. On a host computer, a program first reduces the x‐ray fluorescence spectra to find the peak parameters for each line and another program subsequently identifies the elements.
The concentration correction equations as a consequence of the shiraiwa and fujino equation
Authors: Kuczumow A. 
Published: May 2005

AbstractCertain concentration correction equations are considered as a consequence of the Shiraiwa and Fujino equation. Particular correction equations are related to special physical cases. A set of differential equations, derived on the ground of Claisse's considerations, co‐exist with the set of classic correction equations. The mutual relations between the classic correction equations are presented.
Correction method for the particle‐size effect in the x‐ray fluorescence analysis of ‘Thin’ and monolayer samples
Authors: Hołyńska Barbara , Markowicz Andrzej 
Published: May 2005

AbstractA method of correction for the particle‐size effect in the x‐ray fluorescence analysis of thin and monolayer samples is proposed. The method consists of the measurement of characteristic x‐rays excited by x or γ radiation of two different energies. A concept of a substitute radiometric particle diameter instead of the particle‐size distribution has been introduced in order introduced in order to enable a practical application of the proposed method. The particle‐size correction factors have been obtained theoretically and experimentally for iron oxide (Fe3O4), calcium sulphate (CaSO4) and copper sulphide (Cu2S) with various particle‐size distributions. The application limits of the proposed method have been discussed.
Graphical comparison of mathematical models for quantitative x‐ray fluorescence analysis
Authors: Platbrood G. , Simon S. 
Published: May 2005

AbstractSeveral mathematical models for correcting x‐ray fluorescence intensities are proposed in the literature. However, it is not always easy for the analyst to choose the best one for a particular case. Therefore a modular program has been written to compare automatically mathematical models for quantitative x‐ray spectrometry with the object of determining the best conditions of analysis (models, number and nature of interfering elements and matrix effects). The graphic display of the standard deviation of the standards as a function of the interfering elements used in the correction simplifies and accelerates the interpretation of the matrix effects.
Rapid determination of ash in coke using Compton scattering
Authors: Pandey H. D. , Shastry C. R. 
Published: May 2005

AbstractThe Compton scattering technique for rapid determination of ash content in coal has been extended to coke samples. Some improvements in respect of the sample preparation and possible line overlap and background have been incorporated. A modified regression equation used in this work to compute the x‐ray data is found to yield good results.
L11 and L111 x‐ray absorption discontinuities of Tb in some Tb compounds
Authors: Kumar A. , Salem S. I. 
Published: May 2005

AbstractThe L11 and L111 absorption discontinuities of Tb in various Tb compounds have been recorded using an automated and highly stable x‐ray unit. The energy shifts have been discussed in terms of effective ionic charge. Applying Levy's method, the radii of the first coordination sphere have been calculated from the extended fine structure.
Intercomparison of selected semi‐empirical and fundamental parameter interelement correction methods in x‐ray spectrometry
Authors: Pella P. A. , Sieber J. R. 
Published: May 2005

AbstractFundamental parameter interelement correction methods such as NRLXF are finding increased use in quantitative x‐ray spectrometry. The purpose of this work was to compare the results obtained with each of the three options in NRLXRF, namely empirical, full, and theoretical, with a semiempirical model such as Rasberry‐Heinrich and an NBS fundamental parameter method to check for consistency. Well characterized alloys were chosen for making the intercomparison.
An overview of EXFNBS—A data reduction procedure for energy‐dispersive XRF with secondary target excitation
Authors: Myklebust R. L. , Pella P. A. , Thorne B. 
Published: May 2005

AbstractAn overview of a fundamental parameter, data reduction procedure for processing energy‐dispersive, x‐ray spectrometric data obtained with monochromatic excitation is described. The programs, called EXFNBS and NBSROI, are written in FORTRAN and correct for interfering x‐ray peaks, escape peaks, background, and x‐ray absorption/enhancement due to interelement effects in a speciment. This procedure is designed to operate in an interactive mode with a minicomputer in real time.
The accuracy and precision of routine energy‐dispersive electron microprobe analysis of serpentine
Authors: Wicks F. J. , Plant A. G. 
Published: May 2005

AbstractA serpentine mineral specimen used for a standard in a Materials Analysis Company Model 400 electron microprobe equipped with a Kevex Model 5000A energy dispersive sperctrometer and an on‐line Hewlett–Packard 2100 computer, was repeatedly analysed during a study of serpentinization. The results of the repeated analyses were statistically analysed and show an acceptable level of accuracy and precision. The relative and absolute errors for the serpentine standard lie within the same ranges as the errors for the other standards (forsterite, enstatite, diopside, kyanite and kaersutite) used, although the standard deviations for the serpentine analyses are slightly greater. These results are within acceptable limits and indicate that serpentine can be routinely analysed by energy dispersed analysis, using a serpentine standard for magnesium and silicon determinations, with the same accuracy but with slightly lower precision than less hydrous silicates. Most elements were present in amounts between 2 to 63 wt% of the oxide in the standards used but 0.31 wt% Al2O3 present in the serpentine standard was routinely determined with acceptable results.
XRF analysis of trace titanium in coal using fundamental parameters
Authors: Garbauskas M. F. , Wong J. 
Published: May 2005

AbstractThe analysis of various elements in coal has become important as coal utilization increases. The application of x‐ray fluorescence (XRF) to this type of analysis is complicated by matrix‐correction needs and lack of matrix‐matched standards. The application of fundamental parameter mathematical corrections using easily obtainable doped graphite standards is evaluated.
Evaluation of a correction method for the particle‐size effect in x‐ray fluorescence analysis of ‘Thin’ and monolayer samples
Authors: Markowicz Andrzej 
Published: May 2005

AbstractThe application limits of a correction method for the particle‐size effect in x‐ray fluorescence (XRF) analysis are estimated theoretically in the presented paper. This correction method requires the use of two sources of exciting γ‐or x‐radiation of different energies.1 The influence of the different values of the parameter t′ (which is a function of the linear absorption coefficients for primary and fluorescent radiation) and the influence of the relative standard deviation, Sr (resulting from counting statistics) have been taken into account in evaluating the efficiency of the method. In addition, the criteria for the selection of the optimum energies of the exciting radiation, the proper times of measurement and the activities of the sources of primary radiation are proposed. An example of the application of the proposed criteria to the determination of iron (as Fe3O4) is presented.
X‐ray production in thin films by electrons with energies between 40 and 100 keV. 2—Characteristic cross‐sections and the overall x‐ray spectrum
Authors: Gray C. C. , Chapman J. N. , Nicholson W. A. P. , Robertson B. W. , Ferrier R. P. 
Published: May 2005

AbstractTwo approximate theories are considered for the production of characteristic x‐rays when thin foil targets are bombarded with electrons with energies between 40 and 100 keV. One, due to Kolbenstvedt, is semi‐classical in nature whilst the other, due to Bethe, contains two parameters which are normally adjusted empirically. Data from six different target materials are presented, but because errors in experimentally derived absolute cross‐sections are large, a comparison is made between theoretical and observed ratios of characteristic Kα photons to bremsstrahlung photons in a 20 eV channel directly beneath the peak. By adjusting the Bethe parameters and using a modified Bethe‐Heitler theory to predict the bremsstrahlung, agreement between experiment and theory of typically 10% is recorded. Finally, a means of simplifying the equations used to enable rapid calculation of x‐ray spectra with a pocket calculator is indicated.
Energy‐dispersive x‐ray fluorescence analysis of silicate rocks for major and trace elements
Authors: Potts P. J. , Webb P. C. , Watson J. S. 
Published: May 2005

AbstractThe performance of an energy‐dispersive x‐ray fluorescence (ED‐XRF) system for the analysis of silicate rocks was investigated in detail. Data are presented to demonstrate the selection of optimum excitation conditions for the major elements (Na‐Fe), analysed on glass beads, and the trace elements (particularly the Rb‐Nb group) analysed on powder pellets. Limitations in spectrum analysis due to overlap interferences are discussed and have largely been overcome using x‐ray profile fitting software. The results show that when operated under optimum excitation conditions, ED‐XRF spectrometry can routinely achieve a high degree of accuracy and precision in the analysis of a wide range of major and trace elements in silicate rocks. For many elements, 2s standard deviations are better than 2% relative. Limits of determination for many trace elements are in the range 4–10 ppm.
Heterogeneity effects in direct x‐ray fluorescence analysis of hair
Authors: Török Sz. , Van Dyck P. , Van Grieken R. 
Published: May 2005

AbstractThe methodology of direct hair analysis by energy‐dispersive x‐ray fluorescence was studied. The effect on the XRF result of having a non‐homogeneous radial distribution of the analyte in a single hair strand and the macroscopic effects in a bundle of hairs were calculated to evaluate possible systematic errors. The detection limits were mapped as a function of the target thickness and surface fraction. It appeared that a 10 mg cm−2 sample thickness, i. e. a target with about four layers of hair strands, is recommended. The standard deviation of this simple direct analytical method is 6–19% for some important elements. Discrepancies with neutron activation analysis had a mean value of around 15%. About twelve elements can be determined simultaneously on a routine basis.
Reflective properties of beryl and gypsum crystals in the 1 keV photon energy region
Authors: Belin E. , Zuckerman S. , Sénémaud C. 
Published: May 2005

AbstractReflexion Curves from gypsum and beryl crystals have been calculated using the dynamic theory of x‐ray diffraction, assuming that the crystal is perfect, and taking into account the photoabsorption of incident photons by the crystal. The calculations were performed for two values of photon energy: 851 eV (Ni Lα emission) and 1098 eV (Ga Lα emission). The results are discussed comparatively.
A modification of Kramers' law for the x‐ray continuum from thick targets
Authors: Brunetto M. G. , Riveros J. A. 
Published: May 2005

AbstractThe intensity of an x‐ray continuum had been generated theoretically for incident electron energies between 10 and 45 keV, radiated photon energies between 2 and 40 keV and over the whole range of atomic numbers (from Z = 1 to 100). For these cases a relatively simple expression was found which shows the dependence of continuous radiation on the atomic number, incident electron energy and radiated energy. In order to compare observed intensities with this expression, we have made corrections for self‐absorption in the target, for loss of ionization due to backscatter and for absorption by the exit window of an x‐ray tube. Our expression provides a better description of experimental observations than dose Kramers' equation.
Radiative Auger transitions and their consideration in deconvolution of energy dispersive x‐ray spectra
Authors: Marageter E. , Wegscheider W. , Müller K. 
Published: May 2005

AbstractThe significance of Auger transitions as spectral components in energy dispersive x‐ray fluorescence spectra is demonstrated. As a summary of fundamental studies on radiative Auger effects the calculation of their energies and relative intensities is demonstrated. These theoretical deductions result in a suitable incorporation in least‐squares techniques by coupling the Auger transitions to the corresponding photopeak originating from the same type of primary vacancy as a function of energy. The simplifications involved, and the removal of systematic misinterpretations and of high correlations of model parameters, are discussed.
Evaluation of the use of Gaussian ϕ(ρz) curves in quantitative electron probe microanalysis: A new optimization
Authors: Bastin G. F. , Van Loo F. J. J. , Heijligers H. J. M. 
Published: May 2005

AbstractA computer program based on the use of Gaussian expressions for the x‐ray distribution with depth [ϕ(ρz)curves] was tested on its usefulness for quantitative electron probe microanalysis. As the good results originally claimed for a similar program could not be reproduced initially, it was subjected to a detailed analysis. As a result, some modifications in the approach are proposed. Apart from increasing the speed of calculation considerably, the modified expressions provide a better insight into the delicate balance which has to exit between the relevant quantities involved. After a new optimization process the modified program was tested on about 450 published microanalyses. The results show that the ϕ(ρz) approach is indeed very promising as a narrow histogram with an r. m. s. value of 5. 4% could be produced. Finally, some suggestions are made for future improvements.