bluuebunny/crossref_metadata_2025_split huggingface dataset:
Depth Profiling of Ceramic Specimens using Multi-Wavelength X-Ray Bragg-Brentano Diffraction Data with Particular Reference to Zirconia-Aluminas
Authors: van Riessen A. , O'Connor B.H. 
Published: March 2019

AbstractDepth profile analysis of phase composition, residual strain and crystallite size in ceramic specimens can be determined by varying the information depth (ID) as defined by Delhez et al. (1988) for an x-ray opaque specimen. The information depth may be controlled by making use of the dependence of ID on Bragg angle and by selecting wavelengths which give appropriate x-ray absorption within the specimen.Procedures are outlined for extracting depth profiles for (i) composition from intensity data and (ii) residual strain and crystallite size from peak width data. Results are described for both discrete-peak and Rietvetd pattern-fitting analysis of zirconiaalumina specimens for which preliminary results have been reported by van Riessen et al. (1990).
A Low Cost Secondary Two Theta Standard for Powder Diffractometry
Authors: Stabb David J. 
Published: March 2019

AbstractSilicon powder, available as a Standard Reference Material, fulfills most of the requirements for a two theta standard. However, It has no diffraction lines at the low 2θ values characteristic of some species. Standard synthetic mica is available but expensive.Experiments with a commercially available high silica zeolite have shown that it is a valuable secondary standard. It is non-toxic, stable, inexpensive and possesses a large (24 Å) unit cell. Peaks show clearly from 14 Å (6°2θ for Cu Kα).An example is given of the use of this secondary standard in determining lattice parameters.
Formalism for the Evaluation of Pseudo-Macro Stress Fields σ33(z) from Q-AND ψ-Mode Diffraction Experiments Performed with Synchrotron Radiation
Authors: Ruppersberg H. 
Published: March 2019

AbstractA self-consistent scheme is proposed for the evaluation of stressfields which vary strongly within the penetration depth of the X-rays in polycrystalline specimens which are elastically isotropic and homogeneous on a macroscopic scale. Very precise diffraction experiments have to be performed for practical applications.
Material Strength Evaluation and Damage Detection by X-Ray Diffraction
Authors: Goto Toru 
Published: March 2019

AbstractThe number of products that have to be inspected in pre-service and/or in service is increasing. Not only inspection for flaws are required increasingly, using the ordinary non-destructive testing, but also inspection of material characteristics, such as material strength evaluation and/or damage detection. For such inspection, X-ray diffraction has great possibilities as one of the most promising techniques, because it is (a) noncontact, (b) very sensitive to changes in parameters of the crystalline structure, and (c) suitable for surface observation.In this paper, three topics are introduced which will be useful in the field of material strength evaluation and damage detection using X-ray diffraction.
X-Ray Analysis of Stress in a Localized Area by Use of Imaging Plate
Authors: Yoshioka Yasuo , Ohya Shin'ichi 
Published: March 2019

AbstractFor determination of stress in a localized area, we combined a modified single exposure technique and the imaging plate, which is an x-ray digital area detector. With the, single exposure method, stress value is obtained from lattice strains in two directions with a single incident x-ray beam directed at an oblique angle. However, since diffraction data around a whole Debye-Scherrer ring was used in this study, a stress value can be accurately determined in comparison with the single exposure method. We observed the DS ring by use of the imaging plate with requiring only a short exposure time. Lattice strains in many directions on a DS ring were measured by an image analyzer connected to a computer; we verified the effectiveness of this method.
Saxs Measurement of Morphology and its Relationship to Melting Point Depression in Poly(Beta-Hydroxybutyrate-CO-Beta-Hydroxyvalerate) Random Copolymers
Authors: Bluhm Terry L. , Orts William J. , Marchessault Robert H. 
Published: March 2019

AbstractSmall-angle x-ray scattering (SAXS) and wide-angle x-ray diffraction (WAXD) data are used to establish relationships among the degree of crystallinity, melting temperature and lamellar thickness for random copolymers of poly(β-hydroxybutyrate-co-β-hydroxyvaierate) (PHB/V). The morphology of this isodimorphic system is best described by a two phase model consisting of crystalline and amorphous domains having density fluctuations within each domain. The Sanchez-Eby inclusion model is used to predict melting point depression in these materials and, combined with SAXS data, to gain insight into the degree of inclusion of hydroxy valerate units within the polyhydroxybutyrate crystalline domains.
Examples of Analysis from an Integrated X-Ray Fluorescence Analysis System Using NRLXRF
Authors: Artz B. E. , Rokosz M. J. 
Published: March 2019

Methods of correction for matrix differences are required in X-ray Fluorescence (XRF) Analysis when the overall composition of the unknowns is substantially different from the available standards. Sample preparation techniques used to minimize matrix differences often require development time and can consume irreplaceable sample material. Alternatively, the increasing computer power available to the analyst and the refinement of computer programs using fundamental parameter calculations has made this approach more attractive.A system-consisting of a Siemens SRS-1 wavelength dispersive spectrometer (WDS), a KEVEX 0810-A/NS880 energy dispersive spectrometer (EDS), software for data collection and manipulation and a 40 element version of the NRLXRF fundamental-parameters analysis program has been put together to simplify XRF analysis of samples lacking standards of a similar composition. This configuration is shown schematically in Figure I.
The X-Ray Analysis of Uranium Ores for Iron Sulfide Minerals
Authors: Durbetaki A. J. , Carlson R. H. , Quail T. F. 
Published: March 2019

Hydrogen peroxide is used to extract uranium by the in situ leaching of sandstone ore deposits containing uraninite (UO2). Since FeS2 minerals, marcasite and pyrite, also occur in these deposits and they consume hydrogen peroxide in their oxidation, it is important to determine their concentration.A quantitative X-ray diffraction (XRD) method was therefore developed in order to monitor the concentration of marcasite and pyrite in sandstone ores.
Energy Dispersive XRF Analysis of Lubricating Oil Additives with Secondary Target Excitation and the EXACT Fundamental Parameters Program
Authors: Stehr Kenneth C. 
Published: March 2019

The need for rapid and accurate analysis of lubricating oil additives is firmly established by the petroleum industry. The application of energy dispersive X-ray fluorescence spectrometry techniques to this analysis is a valuable aid in achieving reliable and fast quality control of these product types.Due to the large concentration variations possible for the elements of interest within these materials (principally Zn, Ca, P, S at 0-20%), interelement effects can become significant. In order to correct for interelement effects, historical XRF methods have relied on a large number of standards for each element to be determined or matrix matching with standards closely bracketing the unknown sample concentrations.
X-Ray Residual Stress Mapping in Industrial Materials By Energy Dispersive Diffractometry
Authors: Bechtoldt C. J. , Placious R. C. , Boettinger W. J. , Kuriyama M. 
Published: March 2019

AbstractAn application of energy dispersive diffractometry to the measurement of residual strains (stresses) in the interior of industrial materials is described with particular emphasis on the use of high energy (up to 250 keV) x-ray photons. The use of high energy photons permits better penetration into materials. Hence diffraction data for evaluating bulk residual strains can be obtained in the transmission geometry in contrast with the conventional angular dispersive diffractometry, which uses Bragg reflections from the surface of materials. The reliability and sensitivity (detectability of small strains) of the energy dispersive method are demonstrated through its application to mapping of residual stress distributions across weld zones in Alaskan pipe line segments (API5LX65). The detectability of strain variations within materials depends on x-ray optical resolution and statistics.
Estimation of Ahisotropy of X-Ray Elastic Modulus in Steel Sheets
Authors: Nagashima Shin-ichi , Shiratori Masaki , Nakagawa Ryuichi 
Published: March 2019

The oscillation from a linear relation in the 20 vs. sin2ψ diagram has been a most important problem in X-ray stress measurement. There are, therefore, a number of papers concerned with the X-ray elastic constant, lattice strains under stresses and evaluation of stresses of textured materials.The purpose of the present study is to analyze the three-dimensional orientation distribution of steel sheets by means of the Vector method proposed by Ruer and Baro, and to calculate the elastic modulus of textured sheets by means of a finite element method (FEM) using the three-dimensional orientation distribution, and then to calculate the strain/stress ratios vs. the directions defined by the angles between the specimen normal and the normal to the diffracting planes.
X-Ray Fractography On Fatigue Fracture Surfaces of Aisi 4340 Steel*
Authors: Hirose Yukio , Yajima Zenjlro , Mura Toshio 
Published: March 2019

The X-ray fractographic technique was applied to fatigue fracture surfaces of tempered AISI 4340 steel. Residual stresses and half-value breadths were measured by the X-ray diffraction.In the present paper, the residual stresses and plastic strains on fatigue fracture surfaces and some parameters in the fracture mechanics were investigated. A simple model of mechanics was proposed to explain these experimental results.
Application of Synchrotron Radiation Excited X-Ray Fluorescence Analysis to Micro and Trace Element Determination
Authors: lida Atsuo , Gohshi Yohichi , Maezawa Hideki 
Published: March 2019

AbstractMicro and trace element analysis by X-ray fluorescence was carried out using synchrotron radiation from a bending magnet and an undulator for hard and soft X-ray excitation respectively. The minimum detection limits obtained in the hard X-ray region were less than pg, which corresponds to a spatial resolution of less than a hundred micronmeters, with a detection limit of a few ppm. Light elements such as oxygen, nitrogen and carbon in silicon compounds were analyzed by soft X-ray emission spectroscopy using undulator radiation. The minimum detectable amount of the light elements was greatly improved, since undulator radiation is very strong in intensity, and is highly collimated.
A New Method for Orientation Distribution Function Analysis
Authors: Matsuo Munetsugu , Kawasaki Koichi , Sugai Tetsuya 
Published: March 2019

AbstractAs a means for quantitative texture analysis, the crystallite orientation distribution function analysis has an important drawback: to bring ghosts as a consequence of the presence of a non-trivial kernel which consists of the spherical harmonics of odd order terms. In the spherical hamonic analysis, ghosts occur in the particular orientations by symmetry operation from the real orientation in accordance with the symmetry of the harmonics of even orders. For recovery of the odd order harmonics, the 9th-order generalized spherical harmonics are linearly combined and added to the orientation distribution function reconstructed from pole figures to a composite function. The coefficients of the linear combination are optimized to minimize the sum of negative values in the composite function. Reproducibility was simulated by using artificial pole figures of single or multiple component textures. Elimination of the ghosts is accompanied by increase in the height of real peak in the composite function of a single preferred orientation. Relative fractions of both major and minor textural components are reproduced with satisfactory fidelity In the simulation for analysis of multi-component textures.
An Electro-Optical X-Ray Diffraction System for Grain Boundary Migration Measurements at Temperature
Authors: Green Robert E. 
Published: March 2019

Considerable work has been undertaken in order to gain an understanding of the mechanisms responsible for the generation of recrystallization textures developed upon annealing of cold-worked metals. Most direct measurements have consisted of measuring the increase in average diameter of the largest grain growing into a polycrystalline aggregate. Experimental measurements of individual boundaries migrating into deformed single crystals, though of a more fundamental nature, have been made by far fewer investigators. This is probably due to the increased experimental difficulties associated with careful control of such experiments. Most previous investigators have made grain boundary migration measurements by the heat-cool-etch method, despite the fact that it has several marked disadvantages. Other investigators have constructed an X-ray goniometer furnace and used it to measure grain boundary migration rates while the test specimen was maintained at temperature. Since there have been no published reports of the use of such a system in the past thirteen years, it must be concluded that the technique was unsuccessful in general.The system described in the present work is relatively simple in design and extremely simple to use. Not only does it permit absolute measurement of grain boundary position at temperature but it also permits boundary migration measurements to be made of extremely fast moving boundaries. The basic components of the system are as follows. A continuous spectrum X-ray beam is converted by a slit collimating system into a beam which is incident along the entire length of the test specimen. This beam is interrupted by a wire grid just prior to impingement on the test specimen. The test specimen is supported vertically in a furnace maintained at the temperature required for grain boundary migration. The various diffracted X-ray beams pass out of the furnace through a highly reflecting insulating baffle made from very thin aluminum foil and impinge on a fluorescent screen. This screen converts the X-ray image into a visible one which is amplified and recorded using the electro-optical system.
One-Dimensional, Curved, Position-Sensitive Detector for X-Ray Diffractometry
Authors: Sleaford B. , Perez-Mendez V. , Wagner C.N.J. 
Published: March 2019

AbstractA curved, one-dimensional position-sensitive detector has been designed and constructed for the measurement of the scattering patterns from non-crystalline materials. The chamber is a one-dimensional, pressurized, gas-filled detector with delay line readout for position encoding. It covers an angular range of 45° in 2θ, and its quantum efficiency is 80% and 50% for 17.5 and 60 KeV x-rays, respectively, when using a Xe-20%CO2 gas mixture at 7 atm.
A Fast Algorithm for Fundamental Parameter Calculations
Authors: Pöhn Ch. , Ebel H. 
Published: March 2019

AbstractA fundamental parameter algorithm for quantitative XFA with characteristic Kα- and Lα-radiations of the specimens is presented. This allows an application to programmable pocket calculators or a fast evaluation of measured countrates for the unknown composition of the specimen by means of PCs. For the practical utilization we need the incidence angle and the takeoff angle of the x-rays in the instrument, the high voltage V in kV which is supplied to the x-ray tube (E0) and reference measurements on either pure elements or a single reference specimen. The quality of the analytical results depends on the concentration differences of the unknown specimen and the reference specimen.
An Algorithm for the Description of White and Characteristic Tube Spectra (11 ≤ Z ≤ 83, 10keV ≤ Eo≤ 50keV)
Authors: Ebel H. , Wiederschwinger H. , Wernisch J. , Pella P.A. 
Published: March 2019

Kramers described the cross section of electron interaction with target atoms of atomic number Z bywhere Eois the kinetic energy of impinging electrons, and E o S) the energy of x-ray photons of the continuum, Smith et al modified this equation, introducing an exponent x, so thatWe applied the cross-section σS, Eto the evaluation of experimental results. The evaluation of the measured spectral responses of the x-ray signals nEwas performed bywhere f(deff) describes the absorption of x-rays of energy E in the target, REaccounts for backscattering of electrons, DEquantifies the efficiency of x-ray detection within the solid angle Ω.
Grazing Incidence X-Ray Fluorescence Analysis using Synchrotron Radiation
Authors: Iida Atsuo 
Published: March 2019

AbstractThe X-ray fluorescence analysis of a trace element under a grazing incidence condition has been developed using synchrotron radiation. The interference effect plays an important role for determining the depth distribution of the elemental concentration. The elemental distribution above, on or below the material surface has been studied. The glancing angle dependence of the X-ray fluorescence signal around the critical angle strongly reflects the elemental distribution, and can be used to determine the position of the element of interest.
Grazing Incidence X-Ray Spectroscopy for Thin Layer Analysis
Authors: Hashimoto Hideki , Nishioji Hiroshi , Saisho Hideo 
Published: March 2019

AbstractReflection and fluorescence intensity profile curves for thin films were measured under the grazing incidence conditions using synchrotron radiation. A titanium layer and a carbon / titanium bilayer sputtered on a silicon wafer were subjected to heat treatment. The analysis of the reflection and fluorescence profile curves shows that the sample without the heat treatment has another high-density layer on the surface or interface, and that the heat treatment results in the removal of the high-density layer and the formation of a thick homogeneous layer.
The Comparison of Three Excitation Modes in the Energy Dispersive X-Ray Fluorescence Analysis
Authors: Kanngieβer Birgit , Bockboff Burkhard , Scheer Jens , Swoboda Walter 
Published: March 2019

AbstractWith a new irradiation chamber a comparison of three excitation modes under same conditions and with the same material has been done. The results of this comparison are presented in the following manner: - Barltla scattering (graphite) versus Bragg reflection (HOPS) - Bragg reflection (Mo) versus secondary target fluorescence (Mo) - secondary target fluorescence (Sn) versus Barkla scattering (graphite) Excitation spectra and detection sensitivities of a NBS standard will be discussed for the different modes. The Barkla scattering was found to be the best excitation mode for a wide elemental range.
Synchrotron Radiation X-Ray Fluorescence Analysis with a Crystal Spectrometer
Authors: Ohashi Kazutaka , Takahashl Mamoru , Gohshi Yohichi , Iida Atsuo , Eishimoto Shunji 
Published: March 2019

AbstractA wavelength dispersive spectrometer which consists of a flat crystal analyser and a position sensitive proportional counter has been developed for X-ray fluorescence analysis using synchrotron radiation. The advantages of this spectrometer are high energy resolution, multielemental nature, and high efficiency, and these match well "with the high brightness synchrotron X-ray source. The minimum detection limits are of the order of ppm or pg. An application to elemental mapping has also been demonstrated. The present system is useful for practical analysis of small samples or small regions.
Backscatter/Fundamental-Parameters Analysis of Unweighed Samples using Multi-Target, Multi-Crystal Regions of Interest from WDXRF and EDXRF
Authors: Arthur Richard J. , Sanders Ronald W. 
Published: March 2019

AbstractA method has been developed to simultaneously compute matrix corrections from a composite spectrum of multi-target energy-dispersive (EDXRF) and multicrystal wavelength—dispersive (WDXRF) x-ray fluorescence systems, A serial line installed between the WDXRF and EDXRF spectrometers via a PDF 11/34a computer allows acquired wavelength data to be digitally transformed into an energy spectrum. The low-energy x-ray information from the WDXRF unit is then coupled with the backscatter coherent/incoherent information from the EDXRF unit, enabling enhanced quantitative analysis for low-atomic-number (low-Z) elements. The peak resolution obtainable from the WDXRF spectra often removes the necessity for peak-overlap corrections.Backscatter intensities obtained from the EDXRF unit are used to provide information on total sample mass and to correct for matrix effects. The resulting backscatter fundamental-parameter (BFP) calculations generally provide an accurate analysis of samples without prior knowledge of the sample matrix. Such an approach is particularly useful for samples in which quantities of carbon, oxygen, and other low-Z constituents cannot be explicitly determined.Regions of interest (ROI) are created by the computer code “PREP” and processed by the BFP code "MSAP" an extension of the “SAP3” computer program for quantitative multielement analysis by energy-dispersive x-ray fluorescence,
Large-Area X-Ray Micro-Fluorescence Imaging OF Heterogeneous Materials
Authors: Cross B.J. , Lamb R.D. , Ma S. , Paque J.M. 
Published: March 2019

AbstractAn X-ray Micro-Fluorescence (XRMF) spectrometer, with an analysis area of about 100 by 150 microns, has been used to collect 2-dimensional X-ray intensity maps over large-area (5 to 50 mm in X and Y) samples. These intensity maps were collected by scanning the sample on an XY stage, and converting X-ray Energy-Dispersive spectra to peak intensities for the elements of interest. The maps, when displayed using false-color or pseudogray scales, show the distribution of individual chemical elements over the analysis area. These maps can be collected at speeds from about 1 minute per frame (analysing 25 elements simultaneously). Greater precision of chemical intensities, or larger area maps, may require several hours, particularly if extensive data processing is performed at each point. XRMF has advantages over more conventional SEM-EDS X-ray mapping, including sample preparation and presentation, as well as improved signal-to-noise ratios.A technique is described which assists in analyzing the large amount of data which is collected in each map. Principal Component Analysis (PCA) is performed on all of the elemental maps simultaneously. This technique compresses the many elemental intensity maps into a few principal components, resulting in many fewer maps to evaluate. The intensity maps of these principal components display the most pertinent information. They can also be plotted as scatter plots which can help with the partitioning of the data into individual phases. This procedure can potentially be automated as a method for phase analysis. The selected pixels from the scatter plots can be averaged and converted into phase compositions, and the phase information re-displayed on the original elemental or principal component maps.This technique has been applied to a thin section of rock, and to a synthetic multiphase alloy sample.