bluuebunny/crossref_metadata_2025_split huggingface dataset:
Use Of A Solid-State Detector for the Analysis of X-Rays Excited in Silicate Rocks by Alpha-Particle Bombardment
Authors: Franzgrote Ernest J. 
Published: March 2019

The analysis of alpha-excited X-rays has been studied as a possible addition to the alpha-scattering technique used on the Surveyor spacecraft for the first in situ chemical analyses of the lunar surface.Targets of pure elements, simple compounds, and silicate rocks have been exposed to alpha particles and other radiation from a curium-214 source and the resulting X-ray spectra measured by means of a cooled lithium-drifted silicon detector and pulse-height analysis.Alpha-particle bombardment is a simple and efficient means of X-ray excitation for light elements. Useful spectra of silicate rocks may be obtained in a few minutes with a source activity of 50 millicuries, a detector area of 0.1 cm2 and a sample distance of 3 cm. An advantage over electron excitation is the higher characteristic response relative to the bremsstrahlung continuum. Peak-to- background ratios of greater than 100 to 1 have been obtained for elemental targets. Relative efficiencies of X-ray excitation by alpha particles and by X-rays from the curium source have been determined.Resolution of the detector system used is approximately 150 eV for the lighter elements. This is sufficient to resolve the Kα X-rays of the geochemically important elements, Na, Mg, Al, and Si in silicate rocks. Although these and lighter elements are analyzed as well or better by the alpha-scattering and alpha-proton technique, the X-ray mode enables results to be obtained more quickly.The study shows that the addition of an X-ray mode to the alpha-scattering analysis technique would result in a significant improvement in analytical capability for the heavier elements. In particular, important indicators of geochemical differentiation such as K and Ca (which are only marginally separated in an alpha-scattering and alpha-proton analysis) may be determined quantitatively by measuring the alpha-excited X-rays. An X-ray detector is under consideration as an addition to an alpha-scattering instrument now under development for possible use on a Mars-lander mission.
The Determination of the Axis of Lattice Rotation With Respect to a Change is Texture
Authors: Feng C. 
Published: March 2019

It is known that a change in texture may take place in various metals and alloys following cold working, fabrication and recrystallization processes. Such change may be determined by an analysis of the pole figures obtained from the x-ray diffraction data. In numerous occasions, it is analogous to a lattice rotation.In the present paper, a method is derived to identify the axis of rotation with respect to the starting and final texture of a given specimen. Once this axis is identified, the amount and the direction of the lattice rotation can be accurately determined. The techniques in obtaining a solution by mathematical calculation, and by stereographic presentation will be described. Discussion will be made also of the various parameters which may affect the validity and accuracy of the determination.
X-Ray Investigations of Spinel Substrates
Authors: Maurits J. E. A. , Hawley A. M. 
Published: March 2019

Recent advances in MOS integrated circuit technology have opened new, high-volume applications utilizing epitaxial silicon-on- insulating substrates. To provide good quality heteroepitaxial silicon films for the semiconductor industry, a development program has been established to improve both the crystalline quality and the fabrication techniques for the most promising current substrate, magnesium aluminum spinel.The role of X-ray diffraction techniques in the investigation of crystal quality, substrate surface quality, and epitaxial film quality are discussed, and results interpreted as the program is traced from crystal growth to epitaxial film analysis.
Simultaneous X-Ray Emission Analysis of P, Si, Ca, Fe, Al, and Mg in Phosphate Rock Using a Small Computer to Correct for Matrix Variations
Authors: McKinney Charles N. , Rosenberg Arthur S. 
Published: March 2019

Phosphate rock from different sources varies widely in composition. This results in a large interelement effect. A mathematical model was developed to correct for matrix variations in each sample. This model utilizes the X-ray intensity from each of the six elements considered and the mass absorption coefficients of the elements to calculate concentrations. Accurate analyses for P, Si, Ca, Fe, Al, and Mg are obtained using this model. The X-ray instrument is interfaced with a small computer that performs the calculations on each sample and prints the results.Sample preparation, standardization and the computer programs used for sample calculation and standardization will be discussed.
Measurement of Long Range Order in the γ’ Phase of Nickel-Base Superalloys
Authors: Mihalisin J.R. 
Published: March 2019

The long range order parameter (S) has been measured at room- temperature on the γ’ phase extracted from IN-731 and alloys 713C and 713LC by x-ray diffraction techniques. Measurements were obtained from specimens of IN-731 and alloy 713LC in the as-cast condition and after long time rupture testing. The alloy 713 c specimens were in the as-cast and high temperature heat treated conditions.It was found that long range order in the γ’ phase of IN-731 and alloy 713LC was changed very little after long time rupture testing, and after high temperature heat treatment in the case of alloy 713C.
Some Problems in X-ray Stress Measurements
Authors: Cullity B. D. 
Published: March 2019

Some kinds of plastic deformation leave a residual pseudo-macrostress in the material. The existence of this stress in certain specimens introduces errors into the standard x-ray measurement of residual macrostress, namely, in specimens that have been stretched, compressed, bent, rolled, or drawn.No error is involved in x-ray measurements on peened, ground, or machined surfaces, or in specimens where the source of the stress is remote from the surface examined.The x-ray and magnetic evidence for pseudo-macrostress is reviewed.
A Method of Determining the Elastic Properties of Alloys in Selected Crystallographic Directions for X-ray Diffraction Residual Stress Measurement
Authors: Prevey Paul S. 
Published: March 2019

A technique and apparatus are described for obtaining the elastic constant E/(1 + v) in selected crystaliographic directions for the purpose of calibrating x-ray diffraction residual stress measurement methods. The preparation of a simple rectangular beam specimen with two active electrical resistance strain gages applied to the test surface is described. Samples are clamped in a diffractometer fixture designed to minimize displacement errors, and loaded in four-point bending to several stress levels below the proportional limit. A method is described for calculating E/(l + v) and an estimate of the experimental error.Values of E/(l + v) obtained for several alloy-(hkl) combinations are presented. The results indicate that several alloys of current commercial interest exhibit significant elastic anisotropy.
Precision and Reproducibility of Lattice Parameters from Guinier Powder Patterns: Follow-Up and Assessment
Authors: Brown A. , Foris C.M. 
Published: March 2019

AbstractLattice parameters, obtained by least-squares refinement of data from calibrated Guinier powder patterns, are compared in an effort to establish procedures for obtaining reproducible 2θ values with Guiniertype focusing camera techniques. The calibration procedure is discussed and a method of calculation to reduce loss of precision is proposed. Effects of particle size and crushing are also discussed as well as some sources of error such as use of only selected calibrant lines, film background, and mutual interference of powder lines.
The Measurement of Thermally Induced Structural Changes by High Temperature (900°C) Guinier X-Ray Powder Diffraction Techniques
Authors: Fawcett T. G. , Moore Kirchhoff P. , Newman R. A. 
Published: March 2019

AbstractA new method for the collection and analysis of high temperature Guinier x-ray data has been devised at The Dow Chemical Co. This technique can be used to monitor various types of structural transformation and thermal expansions up to 900°C. The thermal expansions of α-Al2O3 and two TiO2 structures, anatase and rutile, have been characterized for their use as high temperature internal standards.
The Determination of Elastic Constants Using a Combination of X-Ray Stress Techniques
Authors: Goldsmith Charles , Walker George A. 
Published: March 2019

AbstractThe powder diffraction x-ray technique commonly used to measure strain in polycrystalline materials requires a knowledge of the elastic constants in order to convert the strain into a stress value. For many materials, these constants are not always known. Another technique to measure strain is the x-ray lattice curvature (substrate bending) method which requires no knowledge of the film elastic constants. The strain is measured in the substrate and requires only the elastic constants of the substrate to convert the measured strain into stress. Using a combination of the powder diffraction technique and a double crystal lattice curvature technique, the elastic constants of TaSi2and WSi2have been determined for various crystallographic directions.
A Phi-Psi-Diffract (Meter for Residual Stress Measurements
Authors: Wagner C.N.J. , Boldrick M.S. , Perez-Mendez V. 
Published: March 2019

AbstractA ϕ-ψ diffractometer has been designed and constructed to evaluate residual stresses in polycrystalline samples by x-ray diffraction. It permits rotations of the x-ray diffraction apparatus, consisting of an x-ray tube and a position-sensitive proportional counter, about two axes ϕ and ψ. The ϕ-rotation from 0° to 360° is carried out about the normal to the surface of the stationary sample, whereas the ψ-motion consists of a rotation from -45° to +45° about an axis lying in the sample surface and the diffraction plane, but perpendicular to the diffraction vector. This ϕ-ψ diffractometer permits the application of the ϕ- and ψ-differential and integral methods for the evaluation of the strain tensor and its gradient averaged over the depth of x-ray penetration into the sample. Assuming that isotropic elasticity theory is applicable, the stress tensor can then be evaluated from the measured strain tensor.
Automated Qualitative X-Ray Fluorescence Elemental Analysis
Authors: Garbauskas Mary F. , Goehner Raymond P. 
Published: March 2019

AbstractA series of FORTRAN IV programs have been written to aid in qualitative x-ray fluorescence (XRF) analysis. These programs have been implemented on a DEC PDP 11/34 computer with an RSX-11M operating system and access the NIH elemental data base (1). The programs and their application to XRF analysis in our laboratory will be described.
A Generalized Matrix Correction Approach for Energy-Dispersive X-Ray Fluorescence Analysis of Paint Using Fundamental Parameters and Scattered Silver Kα Peaks
Authors: Christensen Leif Højslet , Drabæk Iver 
Published: March 2019

AbstractAn energy-dispersive x-ray fluorescence method has been developed for the direct determination of major and minor elements in infinitely thick samples of paint. Matrix absorption and enhancement corrections are iteratively calculated from a knowledge of tabulated fundamental parameters and the unknown weight fractions. An estimate of the significant light element fraction of the bulk sample required for the calculation of matrix attenuation is obtained using the scatter peaks of the silver secondary target. Relative elemental calibration constants and calibration factors for the coherent and incoherent peaks are determined experimentally using either thin-film standards or standards of known total composition. For routine analysis only one absolute standard is required. The method has been applied to different types of paint with a relative standard deviation better than 5% provided the counting statistics are not the limiting factor. The accuracy has been tested by comparing own results with those obtained either from the formulation or from, instrumental neutron activation analysis.
Decomposition Spectrometric Data of Energy Dispersive X-Ray Fluorescence Analysis (EDXRF)
Authors: Smolniakov V. I. , Koltun I. A. 
Published: March 2019

AbstractIt is well-known that in EDXRF, using high-resolution semiconductor detectors, evaluation of x-ray fluorescence radiation line intensities from multiplex spectrometric information represents definite difficulties, especially in automation of measurement-calculation procedures.A common spectrum decomposition problem is to get the following parameters: a number of spectral lines and their centroids, intensities from measured experimental data and their errors.We have developed special software for solving this problem using personal computers and high-level programming language C. It uses profiles of real-form lines of pure chemical elements produced by semiconductor detector spectrometers and these techniques: digital filters with parameters for suppression of background, multiplex structure analysis, and stable linear least-squares fit to get peak intensities. Also it established special criteria for reliability of the results.We compared our investigation with software “EDXRF” (ver.1.32) arid spectrum decomposition with Gaussian peaks.
Recent Developments in Surface and Thin Film Analysis using Low - Energy Electron Induced X-Ray Spectrometry (LEEIXS)
Authors: Romand M.J. , Gaillard F. , Charbonnier M. 
Published: March 2019

AbstractA review is given of the main gas-discharge sources and auxiliary equipments which were used in soft and ultra-soft X-ray emission spectrometry. Special attention is paid to the basic principles and instrumentation of low-energy electron-induced X-ray spectrometry (LEEIXS) whose excitation source is an electron beam generated in a glow-discharge system. Capabilities of LEEIXS in surface and thin film analysis and characterization are illustrated by examples dealing with control and optimization of surface treatment and thin film deposition processes. Sensitivity of the technique down to the submonolayer range and influence of backscattering phenomena are shown.
Multi-Layer XRF Calculations
Authors: Sumini M. , Fernández J.E. 
Published: March 2019

AbstractAn analytical framework for calculation of multiple scattering intensities emitted by a multi-layer sample are obtained with transport theory. The n-th order Flux solution of the Boltzsiann transport equation renders the iterative solution for multi-layers samples of thin or infinite thickness.The first-order intensity is written for a generic sample with I layers and for the predominating interactions in the X-ray regime: the photoelectric effect, and the Compton and the Rayleigh scattering. As an example, the case of a thin deposit on an infinite thickness substrate is discussed.
Multiple Scattering Contributions of Thin Films in Reflection Geometry
Authors: Fernández J.E. , Sartori R. 
Published: March 2019

AbstractThe multiple scattering contributions to the emitted intensity of a thin homogeneous sample under X-Ray excitation are studied with recourse to the Boltzmann transport theory. The corrective terms to the XRF characteristic line due to a second collision of either the photoelectric effect (secondary XRF), or the Compton, or the Rayleigh scattering, are deduced for reflection geometry. Analytical expressions for the intensities are given that allow their computation for variable incidence and take-off beam directions and source wavelength.
X-Ray Photoelectron and Fluorescence Spectra of Several Zirconium Oxide Compounds
Authors: Haruyama Tatsuya , Sasaki Goh , Fukushima Sei , Kuchitsu Kozo , Koshizaki Naoto 
Published: March 2019

AbstractIla group metal - Zr pcrovskitc type compounds (MZrO3, M=Ba. Sr and Ca) and other oxides were studied by XPS to know the effects of M atoms to Zr atoms. And the feasibility of using XPS and high-resolution XRF for the coordination analysis of Zr atoms was examined for some kinds of stabilized zirconia. An almost linear relationship between the energy of Zr 3d peaks and the radii of Ila group metal ions was found, and, a simple model to interpret this relationship has been proposed. However, no relationship between the energy shifts of Zr 3d spectra or Zr Lα1, 2 spectra and the coordination numbers of Zr atoms in the several Zr oxide compounds was found. Thus, the coordination analysis using XPS or high-resolution XRF is not feasible.
Surface and Thin Film Analysis of Metals and Semiconductors using X-Ray Photoelectron Spectroscopy
Authors: Hofmann S. 
Published: March 2019

AbstractX-ray excited Photoelectron Spectroscopy (XPS) has become an indispensable tool for the study of metals and semiconductors. Due to the small mean free path of the photoelectrons In solids of the order of a few nanometers for energies in the keV range, it is a surface analysis technique. Its capability of quantitative analysis of all elements except hydrogen and helium and their chemical bonding states has recently been combined with small area and imaging analysis to typical spatial resolutions of about 10 μm. After a brief survey of the basic capabilities and limitations of XPS, some illustrative examples in typical metals and semiconductor research areas are presented, such as surface contamination and failure analysis in microelectronics, oxidation and corrosion, segregation at surfaces and interfaces, oxide/metal and oxide/semiconductor interfaces, and thin film analysis using angle resolved XPS and sputter depth profiling. Recent developments emphasize improved data evaluation and quantification schemes as well as instrumental capabilities with respect to both high spatial and energy resolution, and high power excitation sources such as synchrotron radiation.
TXRF with Various Excitation Sources
Authors: Wobrauschek Peter , Kregsamer Peter , Streli Christina , Rieder Robert , Aiginger Hannes 
Published: March 2019

AbstractImproving the detection limits in TXRF by optimizing the excitation conditions is the goal of this work. The properties of the exciting radiation due to spectral distribution, polarisation, intensity and energy are investigated and compared to find best conditions. Results are given from experiments performed with synchrotron radiation, Bragg polarized monoenergetic x-rays, high energy cut-off reflector in the primary beam path of a high power x-ray tube and several geometries for the sample reflector.
Problems in the Use of Multilayers for Soft X-Ray Spectroscopy and Analysis: A Comparison of Theoretically and Experimentally Determined Refraction Effects
Authors: Martins E. , Urch D.S. 
Published: March 2019

AbstractRefraction effects cause the effective 2d spacing of multilayers to vary so that the simple Bragg equation is not applicable when such devices are used for soft X-ray spectroscopy. This paper describes how the refraction term can be determined experimentally. These results compare well with dispersion and absorption terms calculated from atomic scattering factors.
Measurements of Low Concentration Components in Iron Ores using Fusion Method
Authors: Yamada K. , Kohno H. , Arai T. 
Published: March 2019

AbstractThe problem of background radiation in X-ray fluorescence trace element analysis of fused-glass iron ore samples is addressed. A first-order model of coherent and Comptcn scattering with primary absorption is presented and used to correct measurements. Overlap coefficients for elements in iron ores are presented. The importance of these corrections is demonstrated. The accuracy achieved with X-ray measurements after background corrections compares well with the accuracy of chemical analysis.
The Local Structure of Chromium(III) in the Mixed Glycerol Aqueous Solution
Authors: Watanabe T. , Taniguchi K. , Ninomiya T. , Ikeda S. 
Published: March 2019

AbstractChromium glycerate solutions are exposed to X-ray absorption fine structure analysis to clarify the local structure around the chromium atom by the use of a laboratory XAFS system. The chromium solution is stabilized by addition of water soluble polyvinyl alcohol so that after excess water, the solution is a kind of homogenized “sol” without any apparent charge to the solution state. The new technique has been developed, because chromium is an element which has relatively small X-Ray absorption.The comformations of two novel chromium glycerate compounds, which are prepared under both NH4OH and NaOH basic conditions, are examined with XANES and EXAFS techniques. From these experiments, it is suggested that these two chromium glycerates may have Cr-O-Cr bridge bonds consisting of chromium dimer complexes in common.
X-Ray Optics for Scanning Fluorescence Microscopy and Other Applications
Authors: Ryon Richard W. , Warburton William K. 
Published: March 2019

AbstractScanning x-ray fluorescence microscopy is analogous to scanning electron microscopy. Maps of the distribution of chemical elements are produced by scanning the specimen with a very small x-ray beam while collecting the XRF spectrum. Our goal is to perform such scanning microscopy with resolution in the range of <1 to 10 μm, using standard laboratory x-ray tubes. In order to increase the radiation flux on the specimen, we are investigating mirror optics in the Kirkpatrick-Baez (K-B) configuration, K-B optics uses two curved mirrors mounted orthogonally along the optical axis. The first mirror provides vertical focus, the second mirror provides horizontal focus. We have used two types of mirrors: synthetic multilayers and crystals. Multilayer mirrors are used with lower energy radiation such as Cu Kμ. At higher energies such as Ag Kct, silicon wafers are used in order to increase the incidence angles and thereby the photon collection efficiency. In order to increase the surface area of multilayers which reflects x-rays at the Bragg angle, we have designed mirrors with the spacing between layers graded along the optic axis in order to compensate for the changing angle of incidence. Likewise, to achieve a large reflecting surface with silicon, the wafers are placed on a specially designed lever arm which is bent into a log spiral by applying force at one end. In this way, the same diffracting angle is maintained over the entire surface of the wafer, providing a large solid angle for photon collection.
Software Development for X-Ray Microbeam Spectroscopy
Authors: Rindby A. , Voglis P. , Nilsson G. , Stocklassa B. 
Published: March 2019

AbstractSoftware has been developed for performing image reconstruction of analytical results from an X-ray microbeam spectrometer. The software system has been developed on a conventional IBM-AT compatible computer and runs under WINDOW 3,0 system. The interactive part is developed as a complete “window-style” program where the operator controls the sample movement, the MCA and the micrograph image from the microscope.A description of the spectrometer and the software system is given. Applications of the technique in analysing documents are presented.
Scanning X-Ray Analytical Microscope using X-Ray Guide Tube
Authors: Shimomura Shuichi , Nakazawa Hiromoto 
Published: March 2019

AbstractA scanning X-ray analytical microscope was constructed using X-ray guide tube(XGT). XGT is a glass capillary which guides and focuses x-rays by total external reflection at the inner wall. The nature of X-ray beam passed through XGT is varied depending on the form of XGT. The cylindrical and conical types were used for the present setup. A small area (10μm × 10μm) of the sample was irradiated by the X-ray microbeam formed by XGT. Fluorescent and diffracted X-rays from the small area were detected by SSD. By scanning the sample in the plane normal to the X-ray microbeam, the intensity distributions of such secondary x-rays were measured and used as picture elements for constructing x-ray mapping images. The sample was a thin-section of an old chinaware. The images suggest a wide application of this instrument.