bluuebunny/crossref_metadata_2025_split huggingface dataset:
Automated Quantitative XRF Analysis Software in Quality Control Applications
Authors: Klimasara Anthony J. 
Published: March 2019

AbstractA menu-driven IBM-PC/MS-DOS software system for quantitative XRF analysis was designed combining elements of pattern recognition (spectral “fingerprinting”) with mathematical correction models. The following topics are covered:-pattern recognition method; N - dimension representation-local empirical Lachance-Traill or Lucas-Tooth & Price models-EGA/VGA intelligent driver for a calibration display-dSASE III Plus “data files - accessed from dBXL/Quicksifver”, dBASE III Plus or from compiled BASIC equipped with “call subroutines”-Examples of applications (stainless steels and ceramics).In this approach, experimental alphas are computed utilizing the closest automatically preselected standards from available data files. Alpha values generated in this fashion we term “local alphas”. An intelligent software program is employed which automatically recognizes the resolution of tiie CRT display and delivers the best possible display for the available equipment. This new design also permits the utilization of dBXL/Quicksitver, dBASE III Plus or compiled BASIC resources for additional on site system customization programming. A dBASE III Plus file format is used for XRF data storage. This permits fast data exchange with a local ASCII database and also with all popular spreadsheet formats. Additionally, there are utility subroutines available which allow direct and rapid manipuiation of dBASE III Plus files in compiled BASIC. Application of this software system and graphics to stainless steels and engineered ceramic materials are demonstrated. RIGAKU Smax/PDP-11/73 and TRACOR X-RAY SPECTRACE 5000/Compaq 386 spectrometers are used in these studies.
Quantitative XRD Analysis by Partial Least Squares Application in a Commercial Product
Authors: Mateos Arthur G. 
Published: March 2019

AbstractA new approach to quantitative XRD by Partial Least Squares (PLS) used region(s) or the entirety of the diffraction pattern of calibration standards (also called a training set) in the model. The basic concept of this approach states that the information in many observed variables, expressed as matrix I = (i1, i2 … , ik,) is concentrated onto a few underlying latent variables, called factors, by the process of data compression. In XRD, the data points of the diffraction pattern are compressed to few factors T, computed according to their ability to explain the variation in the diffraction pattern or matrix I. The procedure incorporates into the model that part of I that is correlated to C concentrations. Data compression preserves the redundancy between variables due to collinearity and stabilizies the predictions against noise in I. The resulting calibration model allows for detection of outliers. Another important effect of data reduction is the ability to analyze muticomponent systems even when lines of the components are overlapped, Examples of quantitative analysis by PLS are demonstrated in the analysis of a commercial product.
Application of Synchrotron and Flash X-Ray Topography to Improved Processing of Electronic Materials
Authors: Winter J.M. , Green R.E. , Green K.A. 
Published: March 2019

AbstractWhite beam transmission topography was used to image defect structures in gallium arsenide single crystal substrates representative of those used for microwave integrated circuit fabrication. A scanning topographic camera was developed for Beamline X-19C at the National Synchrotron Light Source. Acquiring film topographs within a particular range of scan rates and x-ray fluxes was found to produce distorted images. The distortions were shown to be thermoelastic, arising from inhomogeneous deposition of thermal energy through the absorption of residual x-rays. The problem could be circumvented using faster scans with some sacrifice in spatial resolution. Real time electrooptic topographs were recorded using x-ray fluxes about one percent of those used for the film topographs. The potential for reducing the flux requirement to even lower levels which would be accessible to flash x-ray generators is considered.
Calibrating for X-Ray Diffraction Analysis of Trace Quartz
Authors: Renault Jacques , McKee Chris , Barker James 
Published: March 2019

AbstractTrace analysis of quartz at the <0.1 wt% level can be routinely accomplished by x-ray diffraction using rotating pressed-powder briquettes and a peak deconvolution strategy due to Wiedemann, et al. (1937a, b) which permits reproducible determination of background and enhances peak resolution without changing the integrated intensity.Four calibration methods were tested: (1) calibration with perlites microscopically analyzed by Hamilton and Peletls (1988), (2) with artificial mixtures of quartz and glass, (3) with chemical analysis and massbalance calculation of quartz in glass mixtures, and (4) with a new method of additions for XRD.Methods (2) and (4) gave the best results. Method (2) has a precision of 16.9 pet at the 0.1 wt% level and a LLD of 0.05 wt% at 3σ. Method (4) is particularly attractive because large spikes can be used which minimize homogenization errors and permit preparation of standards which have properties very similar to run-of-the-mill samples; the problem of non-zero intercepts is avoided.
Dependence of Stress Constant on Microstructure of Quenched and Tempered Steels in X-Ray Stress Measurement
Authors: Kurita Masanori , Saito Akira 
Published: March 2019

AbstractThe residual stress measurement of quenched and tempered steels is of practical importance because the quenching can sometimes induce the high residual stress which affects the strength of materials. The stress constants of carbon steels quenched and tempered at various temperatures were measured in order to determine the residual stress of steels by x-ray diffraction. The stress constant increased slowly with increasing tempering temperatures below 500°C; it increased rapidly with tempering temperatures above about 500°C, This rapid increase in the stress constant is closely related to the change in microstructure of the steels in tempering; above the tempering temperature of around 500°C, the tempered martensite recrystallized and transformed to ferritic iron and fine cementite particles dispersed in the matrix; these coalesced and grew to be speroidized cementites and finally laminar cementite plates.
New Directions in the X-Ray Diffraction Analysis of Organic Materials
Authors: Jenkins Ron 
Published: March 2019

AbstractThe analysis of crystalline organic phases by X-ray powder diffraction presents special problems, beyond those typically associated with inorganic materials. The large unit cells often associated with organic compounds, combined with the low symmetry of the structures, give rather complicated diffraction patterns which contain many low angle lines. The Bragg-Brentano geometric arrangement employed in most commercial diffractometers gives maximum d-spacing error at low diffraction angles. This, in turn, means that not only can the large d-spacing data be of poor quality, but also that much of the low angle data required for the indexing of the pattern is subject to large errors.
Preliminary Study Of the Behavior Of HPGe Detectors With Ion Implanted Contacts in the Ultralow-Energy X-Ray Region
Authors: Slapa M. , Chwaszczewska J. , Jurkowski J. , Latussynski A. , Huth G.C. , Dabrowski A.J. 
Published: March 2019

AbstractPreliminary study of performance of an HPGe detector with an ion implanted entrance window in the spectrometry of the ultralowenergy x-rays is presented.For the first time it has been shown that almost symmetric photopeaks and absence of low energy tailing can be obtained in this region from HPGe detectors.
X-Ray Diffraction and Fluorescence in the Analysis of Pharmaceutical Excipients
Authors: Durbetaki A. J. , Quail T. F. 
Published: March 2019

The majority of pharmaceutical dosage forms are marketed as tablets which are formulated to satisfy various basic requirements. The analysis of the resultant multicomponent pharmaceutical and product is usually a lengthy task.This paper describes the complementary use of X-ray diffraction (XRD) and X-ray fluorescence spectroscopy (XRS) to characterize and quantify excipients in pharmaceutical tablets.
Internal Strain (Stress) in an Sic/Al Particle-Reinforced Composite
Authors: Ledbetter H. M. , Austin M. W. 
Published: March 2019

AbstractSilicon carbide and 6061 aluminum alloy possess very different thermalexpansion coefficients; 3-3 and 22.5.10-6K-1, respectively. Thus, one expects large internal strains and stresses in these composites because the two constituents form interfacial bonds at high temperatures and are cooled to ambient temperatures. From a simple elastic model, one expects a hydrostatic tensile stress in the aluminum matrix and a-hydrostatic compressive stress in the silicon-carbide particles. Using conventional diffraction geometry, using Cu Kα radiation, we studied three surfaces of a plate specimen. For both phases, we determined the unit-cell dimensions for two situations: unmixed and mixed in the final composite. The silicon-carbide particles showed a compressive stress and the aluminum matrix a tensile stress, seventy-five percent of the yield strength. Measurements show that both stress tensors are approximately hydrostatic.
Bragg-Borrmann X-Ray Spectroscopy from a Line Source
Authors: Das Gupta K. 
Published: March 2019

Earlier, I reported in this conference the results obtained with (i) a three crystal spectrometer (ii) two curved crystal spectrometer of Cauchois type and (iii) spherically bent crystal spectrometer. These instruments were developed to obtain higher resolution that helped us to observe fine structures of Kα1, Kα2 lines of transition elements. Our work has been followed in other laboratories.Here I present the essential points of a very simple spectrometer hitherto unreported. The most attractive feature of the spectrometer is its simplicity of adjustment in a minimum time.
Layer Thickness Determination of Thin Films by Grazing Incidence X-Ray Experiments using Interference Effect
Authors: Sakurai Kenji , Iida Atsuo 
Published: March 2019

AbstractA novel method using Fourier transform algorithm is proposed to determine each layer thickness of multi-layered thin films from interference oscillation observed in X-ray specular reflection. The peak position in Fourier space gives each layer thickness of the film. The principle of the present technique as well as its applications are described.
Light Element Analysis with TXRF
Authors: Streli Christina , Wobrauschek Peter , Aiginger Hannes 
Published: March 2019

AbstractTotal Reflection X-Ray Fluorescence Analysis (TXRF) has become a powerful analytical tool for trace element analysis. Because of its advantages in excitation and background reduction TXRF has been applied for the analysis of light elements (C,O,F,Na,...). A special Ge(HP) detector offering an ultra thin window in combination with a spectrometer specially designed for the requirements of light element analysis was used. Also a new windowless X-ray tube for efficient excitation of the light elements was tested. The system was checked with standard aqueous solutions; detection limits in the ng range (7 ng for O) are obtained.
Application of TXRF in Environmental Research
Authors: Michaelis Walfried , Pepelnik Rudolf , Prange Andreas 
Published: March 2019

AbstractIn the framework of interdisciplinary research projects TXRF has been applied for multielement analysis of rainwater, size-fractionated airborne particulates, throughfall samples and litter fall in forests, soil solutions, seepage water, river water filtrates and suspended particulate matter. Essential aspects of sample preparation techniques are briefly described. Some results are given on trace element fluxes in a forest ecosystem and on contaminant transport phenomena in estuaries in order to demonstrate the outstanding capabilities of TXRF in demanding environmental research projects.
Measurement of Macrosegregations of Steels by X-Ray Microfluorescence
Authors: Welfringer J. , Benoit P. , Guyon M. 
Published: March 2019

AbstractAn apparatus based on X-ray microfluorescence has been developed at IRSID in order to routinely and quantitatively determine the state of segregation in steels. The equipment consists principally of an iron anticathode X-Ray tube, a Si(Li) energy - dispersive detector and a “on the fly” operation in a multi-scale analysis mode. The acquisition of a chromium or manganese mapping in a (150 × 150 mm2) steel sample is possible over a total time of about one hour. The calibration curves for chromium or manganese are linear for the usual compositions of steels between 0.3% to 3%.
Phase Analysis of Metallic Plutonium-Containing Fuel Alloys Using Neutron Diffraction
Authors: Mueller M. H. , Richardson J. W. , Strain R. V. , Hofman G. L. 
Published: March 2019

AbstractPulsed neutron powder diffraction studies at IPNS have expanded our understanding of the phases present in Integral Fast Reactor (IFR) metal fuel alloys at temperatures in the range of reactor operating conditions. We report results from the binary alloy (U-10wt.%Zr) and ternary alloys (U-8%Pu-10%Zr) and (U-19%Pu-10%Zr). Determining the role and the location of Zr and Pu in these alloys is considered of fundamental importance for maximizing engineering efficiency.Rietveld profile analysis was utilized to study the phase diagrams. Data were collected at temperatures ranging from 25-650°C. Although the expected U/Pu/Zr phases (α-U, β-U, γ-U, δ-U/Zr/Pu, ζ-U/Pu) were observed in appropriate temperature ranges, there were some unexpected results. Relative amounts of all phases at each temperature were calculated from Rietveld scale factors and inferences were made as to the location of zirconium and plutonium, i.e. amounts in each phase, from site occupancies and absorption characteristics of the phases present. Finally, we were able to identify ZrO and ZrO1-x inclusion phases in the U-Zr alloy present in very small (0.5-1.0%) amounts.
X-ray Elastic Constants for β-SiC and Residual Stress Anisotropy in a Hot-Pressed Al2O3/SiC(Whisker) Composite
Authors: Predecki Paul , Abuhasan Alias , Barrett Charles S. 
Published: March 2019

AbstractX-ray elastic constants for the 511+333 and the 422 reflections of β-SiC were calculated from the single crystal data of Tolpygo using the Voigt-Reuss, Eshelby-Kroner and x-ray methods. Agreement was satisfactory for the 511+333, but less so for the 422. A hot-pressed α-Al2O3/ 29 vol % β-SiC (whisker) composite was investigated on its 3 principal faces. The total residual strains were found to be consistently anisotropic on all 3 faces suggesting that texture was present in the whiskers as a result of hot-pressing. Assuming no texture in the matrix, it was found possible to determine the average residual microstresses in the whiskers using the theory of Noyan and Cohen, without needing to know the whisker elastic constants or texture. The average microstresses were determined in each phase as well as the average residual macrostresses on each face.
Residual Stresses in Unidirectional Al2O3 Fiber/Silicate Glass Composites by X-ray Diffraction
Authors: Hehn Lucien , Predecki Paul 
Published: March 2019

AbstractUnidirectional continuous fiber composites fabricated from 20 μm diameter α-AI2O3 fibers (duPont FP) and 5 different silicate glass matrices (Corning 9013 and 7740, Owns Illinois N51A and Schott 8229 and 8228) were examined for residual strain and stress in the fibers using x-ray diffraction and the results compared with the predictions of two simple residual stress models. The glasses were chosen to have thermal expansion coefficients ranging from 1.3 to 10.2 x 10-6 /°C, compared with 7.2 x 10-6 /°C for the fiber, so as to produce a range of residual stresses. The magnitudes of the measured normal strains and stresses increased with increasing fiber/matrix thermal expansion mismatch in the order expected except for the sample containing Corning glass 7740 which showed extensive microcracking. Small shear strains were also detected in most of the samples due to the fibers not lying precisely along the presumed uniaxial direction. Agreement with the models was qualitative only but revealed that the residual stresses in the samples containing Corning 7740 and Schott 8229 glasses were substantially less than expected, possibly due to microcracking and/or fiber degradation.
Measuring Triaxial Stresses in Embedded Particles by Diffraction
Authors: Barrett C. S. , Predecki P. K. 
Published: March 2019

The method presented In 1976 for measuring stresses in polymeric materials including fiber-reinforced composites (1,2) yielded directly only one or two of the principal stresses and (elastic) strains in the embedded crystalline particles. The method is now extended so as to yield determinations of all three principal stresses σ1, σ2, σ3 and strains, ε1, ε2, ε3, The method applies to both residual and applied stresses and strains.High angle diffractometry such as is used in ordinary X-ray stress determinations in metal objects is used, with suitable particles being embedded in a homogeneous plastic or reinforced composite before curing.
X-Ray Strain Measurements in IV-VI Semiconductor Super-Lattices at Low Temperature
Authors: Fantner E.J. , Clemens H. , Bauer G. 
Published: March 2019

AbstractMultilayers composed of many thin films of PbTe and Pb1-xSnxTe on BaF2 substrates were grown epitaxially by hot-wall-vapor deposition. In order to investigate the fraction of the total misfit (2.5x10-3 at x=O, 12) accommodated by misfit strain we have performed strain measurements on these superlattices by two different X-ray diffractometer techniques. We also report on substrate induced strain due to different thermal expansion coefficients of films and substrate. For film thicknesses smaller than 300 nm there is clear evidence for almost complete accommodation of lattice mismatch by misfit strain. Below room temperature the substrate induces a tensile strain which is comparable to that of the misfit strain.
X-Ray Tube Improvements for Better Performance in an Energy-Dispersive X-Ray Spectrometer System
Authors: Vane Ronald , Skillicorn Brian 
Published: March 2019

AbstractImprovements in x-ray tube technology for the low-power tubes used in energy-dispersive XRF systems can provide better performance. These improvements are occurring in six areas: thin-window tubes, lower kV capability, higher kV and mA capability, pulsed tubes, smaller focal spots, and miniaturization. These improvements will lead to better excitation of the light elements, analysis of low-mass samples, higher count rates, small spot analysis, and smaller systems.
Lama III - A Computer Program for Quantitative XRFA of Bulk Specimens and Thin Film Layers
Authors: Mantler Michael 
Published: March 2019

AbstractThe previous LAMA I and II programs have been completely rewritten in this new version. Better precision and an order of magnitude increase in speed were achieved with a different numerical method and more efficient code. Fundamental parameters and/or empirical parameter calculations can be used. New routines for the analysis of oxides and other compounds of light elements, and multiple thin film layers with secondary enhancement factors are included.
A Rapid, Low Cost, Manual Fusion Sample Preparation Technique for Quantitative X-Ray Fluorescence Analysis
Authors: Bowling Gerald D. , Ailin-Pyzik Iris B. , Jones David R. 
Published: March 2019

This study compares the quality of the fused samples obtained by three separate methods. The first set of samples was prepared by the method used at USGS in Denver and reported by Taggart and Whalberg (1). The second set was fused by our manual method and cast in graphite molds. The third set was fused in the Herzog HAG-12 automated fusion device.The manual fusion technique requires the use of a muffle furnace capable of 1100°C (2100°F) and graphite molds. No release agents such as KBr and LiBr are required since the disks release easily from the graphite. The 25mm diameter center of the “fire-polished” upper surface of the disk is used for analysis without further surface preparation. This method has been shown to be suitable for preparation of a wide variety of glasses and raw materials including burned dolomite, silicates* high zircon materials such as BCS-388, calcined alumina and alumina refractories.
Quantitative XRFA of Light Elements by the Fundamental Parameter Method
Authors: Mantler Michael 
Published: March 2019

SummaryAnalysis of light elements, such as C, B, and Be, differs from analysis of heavier elements by the low fluorescent yields as well as by the wide gap between their absorption edge energies and the low energy limit of the available tube-photons. Because of the fact that the (relatively large) difference between these energies is transferred to the photoelectron after an ionization event, additional excitations of light elements are very likely to occur. Other possibilities of unusual secondary excitation effects include excitation by Auger electrons and by Lα-photons after K-shell ionization. The order of magnitude of these effects has been computed for the system Fe/Fe3C. The mathematical models are based on the methods of Green and Cosslett, and Scott and Love. Results show that the C-Kα counts of pure carbon are increased by a factor 2.5-3, and count rate ratios in Fe-C binary systems increase by a factor 5-10, depending upon the experimental conditions. Fit coefficients for mass absorption coefficients of Fe and C have been calculated from experimental data collected by Saloman and Hubbel for energies between 100eV and 1keV.
XRF Analysis of Pb in Occasional Paint Chips
Authors: McKee Chris , Renault Jacques 
Published: March 2019

AbstractFederal laws require that urban redevelopment projects characterize the Pb hazard of old painted surfaces. In large metropolitan surveys, the Pb analyses are commonly obtained with a portable XRF unit; however, for small surveys, capital investments in such instrumentation may be unwarranted. In 1988, the city of Las Cruces, NM, requested our help in providing needed Pb in paint analyses. We developed an economical XRF method for Pb analysis suitable for small scale urban surveys and the requirements of individual home owners, it is described below.1) A standard wavelength dispersive XRF spectrometer is used to determine the CI countrate from a 3.6 cm KCl disk and the countrate per square cm is computed. 2) The paint chip is weighed to the nearest 0.1 mg and cemented onto the disk. 3) The prepared disk is counted for CI, Pb, and Rb using the same spectrometer. 4) The CI countrate deficit is used to compute the area of the paint chip. 5) The mass of Pb corrected for Rb interference is determined from an appropriate calibration curve, and the results are reported in mg Pb/cm2.The Pb analysis is calibrated against geochemical standards. Spex Mix containing Pb is sprinkled on double faced mylar tape of known area and used as an independent check on the calibration curve. We present the results of our calibration curves and our analytical experience over the last 5 years.
Quantitative XRD Analysis of Advanced Coal Combustion Solid Residuals by the RIR Method
Authors: Bender J.A. , Solem J.K. , McCarthy G.J. , Oseto M.C. , Knell J.E. 
Published: March 2019

AbstractReference intensity ratios (RIRs) with zincite (ZnO) as the internal standard have been measured and calculated for key phases in coal combustion solid residuals. Detailed comparisons of measured and calculated corundum RIRs (converted from zincite RIRs), and literature I/Ic values led to the conclusion that for best results, laboratory measured values must be used. Using measured zincite RIRs and standard mixtures of important crystalline phases, a protocol for routine semi-quantitative analysis has been developed. The need to grind under ethanol to minimize decomposition of hydrated phases was demonstrated. An unusual procedure employing mixed peak and integrated intensities in the RIR of one key phase, ettringite (Ca6Al2(SO4)3(OH)12-26H2O), has been adopted for this protocol.