bluuebunny/crossref_metadata_2025_split huggingface dataset:
High Energy Resolution X-Ray Spectrometer for High Count Rate Xrf Applications
Authors: Rossington C. S. , Madden N. W. , Chapman K. 
Published: March 2019

AbstractA new x-ray spectrometer has been constructed which incorporates a novel large area, low capacitance Si(Li) detector and a low noise JFET (junction field effect transistor) preamplifier. The spectrometer operates at high count Tates without the conventional compromise in energy resolution. For example, at an amplifier peaking time of 1 p.sec and a throughput count rate of 145,000 counts sec-1, the energy resolution at 5.9 keV is 220 eV FWHM. Commercially available spectrometers utilizing conventional geometry Si(Li) detectors with areas equivalent to the new detector have resolutions on the order of 540 eV under the same conditions. Conventional x-ray spectrometers offering high energy resolution must employ detectors with areas one-tenth the size of the new LBL detector (20 mm2 compared with 200 mm2). However, even with the use of the smaller area detectors, the energy resolution of a commercial system is typically limited to approximately 300 eV (again, at 1 μsec and 5.9 keV) due to the noise of the commercially available JFET's. The new large area detector is useful in high count rate applications, but is also useful in the detection of weak photon signals, in which it is desirable to subtend as large an angle of the available photon flux as possible, while still maintaining excellent energy resolution. X-ray fluorescence data from die new spectrometer is shown in comparison to a commercially available system in the analysis of a dilute muhi-element material, and also in conjunction with high count rate synchrotron EXAFS applications.
Ultra-High Vacuum Grazing Incidence Small Angle X-Ray Scattering Camera for in Situ Surface Analysis
Authors: Parrill Joanne Levine , Cohen Jerome B. , Chung Yip-Wah 
Published: March 2019

AbstractAn ultra-high vacuum chamber designed for in situ grazing incidence small angle x-ray scattering (GISAXS) surface analysis is described. Unique features of this equipment are the precision rotary feedthrough for angular alignment of the sample, the sample heating design, the Be window arrangement, and the compatibility of this chamber with both a rotating anode and a synchrotron beamline. This chamber was used as part of a GISAXS camera utilizing a 18 kW Rigaku rotating anode, pin-hole collimation, and a position sensitive detector. The resolution of this camera was 0.007 A-1 with a 1.4 mm wide beamstop and CuKα
Total Reflection X-Ray Fluorescence Spectroscopy: Analysis Of Gaas And InGaAs
Authors: Filcs-Sesler Leigh Ann , Plumton Don , Kao Yung-Chung , Kim Tae S. 
Published: March 2019

AbstractThis article explores applications of total reflection x-ray fluorescence (TRXRF) to GaAs processes. The applications include determination of surface contamination and InGaAs layer thicknesses. Surface contamination can deteriorate device performance and can occur in starting substrates and in subsequent processing. We demonstrate that TRXRF is a quick, nondestructive method for identifying sulfur contamination on incoming wafers and low levels of metallic impurities from device fabrication. Variable angle TRXRF has been used to determine heterostmeture film thickness, measuring films of InGaAs on GaAs as thin as 4 nm.
Application of Microbeam X-Ray Technique to the Evaluation of the Plastic Zone Size of Fatigued Steels
Authors: Izumiyama Akimasa , Yoshioka Yasuo , Terasawa Masao 
Published: March 2019

The microbeam X-ray diffraction technique was used for the evaluation of fracture analysis on the fatigued low carbon steel specimens.It is possible to evaluate both monotonic and cyclic plastic zone sizes beneath fatigue fracture surface. Thus the stress intensity factor can be estimated.
Experimental Study of Precise Peak Determination in X-Ray Powder Diffraction
Authors: Huang T. C. , Parrish W. , Lim G. 
Published: March 2019

AbstractThe combined derivative method (accompanying paper) was tested with a large number of experimental patterns to illustrate its use in various difficult problems commonly arising in peak search analysis of X-ray diffraction data. Patterns obtained with various step sizes, resolution, counting statistical noise, and profile widths were used. The precision in 2θ determination and overlap resolution are in good agreement with those previously obtained from calculated profiles, raise identification of noise as diffraction peaks was eliminated by using a convolution range proportional to the full width at half maximum. Peak search results (both 2θ and intensity) were also compared to those obtained by profile fitting to illustrate the different characteristics of these two methods.
Residual Stress Relaxation in Cemented Carbide Composites Studied Using the Argonne Intense Pulsed Neutron Source
Authors: Krawitz A. D. , Roberts R. , Faber J. 
Published: March 2019

AbstractCemented carbide composites with a WC hard phase and a Co-Ni alloy binder phase have been subjected to monotonic and cyclic deformation and studied using the high resolution General Purpose Powder Diffractometer at the Argonne Intense Pulsed Neutron Source. Upon deformation, relaxation of bulk differential thermal residual stresses, tensile in the binder and compressive in the carbide, is observed to occur as a function of loading mode and plastic strain via shifts in diffraction peak positions. In addition, peak breadth behavior indicates broadening. At low plastic strain this is due primarily to a range of residual stress and at high plastic strain it is attributable to the plastic deformation alone since relaxation is essentially complete. The appropriateness of neutrons is discussed.
Computer-Assisted Alignment of a Guinier X-Ray Powder Diffraction System
Authors: Fitzpatrick J.J. , Pressnall J.S. 
Published: March 2019

AbstractDigitized data acquisition and subsequent peak-profile fitting are used in aligning and maintaining the Guinier diffraction system in this laboratory. Utilization of a stepping motor driven goniometer along with profile analysis allows rapid and reproducible alignment while providing a means to investigate the types and magnitudes of errors introduced by various misalignments of the optical system.
Analysis of Graphite in Caststeels using XRFA
Authors: Wariwoda L. , Mantler M. , Weber F. 
Published: March 2019

SummaryFor carbon analysis in an iron-matrix the C-Kα intensity is not only a function of the amount of graphite. but also of the diameter of the spherolites and, for a given total carbon content, of the graphite/cementite ratio. In order to verify this, steel and caststeel sample surfaces were photographed before and after etching and the images digitized. The arcal fractions covered by graphite, cementite, and iron were used to compute the corresponding individual weight fractions and total carbon contents. Count rates were drawn to the scale of these as well as of the nominal carbon concentrations.
O K-V Spectra of Oxides and Superconducting Materials
Authors: Sakai Masahiro , Hayakawa Shinjiro , Kawai Jun , Gohshi Yohichi 
Published: March 2019

AbstractOxygen K-V (Kα) X-ray fluorescence spectra of MgO, Cu2O, CuO, La2CuO4, La2-xSrxCuO4, YBa2Cu3O7-x , and GdBa2Cu3O7-x are measured. The local (oxygen) and partial (2p) electron density of states (DOS) of these compounds are calculated by the cluster approximation with the discrete variational (DV) Hartree-Fock-Slater (Xα) method. The calculated O 2p DOS are compared with the measured X-ray fluorescence spectra. It is found that the measured 0 K-V X-ray fluorescence line shapes are well reproduced by the O 2p DOS calculated by a cluster including the second nearest neighbor atoms (oxygen atoms) in the solids. This indicates that the oxygen K-V X-ray emission spectra reflect the oxygen-oxygen orbital hybridization in the solid as well as the oxygen-metal orbital hybridization.
Raw Materials Analysis by XRF in the Cement Industry
Authors: Babikian Sona H. 
Published: March 2019

AbstractThe sources of raw materials used in the manufacture of Portland cement include pure to argillaceous limestones, shale and clay, plus minor quantities of sand, iron ore, fly ash, coal ash and suitable industrial wastes. To ensure a high quality product, rapid - precise - reproducible and practical analytical techniques are required. Quantitative XRF analysis techniques meet those demands.For this comparative technique, the instrument used is a wavelength dispersive sequential spectrometer. The advantages and the drawbacks of the technique are discussed, along with the procedure of the specimen fused bead preparation. The importance of calibration standards and unknown samples being prepared in an identical manner, and being presented to the instrument under similar conditions, is stressed. International and synthetic standards, concentration ranges for the five major elements, mathematically generated coefficients to correct absorption and enhancement effects, and a summary of the standard error of estimates are examined and discussed.The accuracy of the method is verified by the analysis of known standard reference materials such as obsidian rock, coal fly ash, argillaceous limestone and blastfurnace slag. The values are compared with the known certified values.
Proposed Methods for Depth Profiling of Residual Stresses using Grazing Incidence X-Ray Diffraction (GIXD)
Authors: Predecki Paul , Zhu X. , Ballard B. 
Published: March 2019

AbstractTwo proposed methods are described for obtaining the depth profiles (τ-profiles) of strains and stresses as a function of the 1/e penetration depth τ, using GIXD in the asymmetric geometry, without the need for layer removal. In the first, the ψ-method: ψ is varied, for a given reflection, while holding τ constant, by varying the wavelength λ and adjusting the incident angle α so as to maintain τ constant. This allows dϕ,ψ vs Sin2ψ plots to be obtained at constant τ. In the second, the ϕ-integral method: interplanar spacings dϕ,ψ are measured for ϕ values from 0 to 2π, at constant ψ and τ by holding α fixed. Two ψ values, i.e. two wavelengths, are needed to obtain the whole strain tensor, but if the sample is quasi-isotropic and the stress state is biaxial, only one wavelength is needed. A direct method is also described for obtaining the profiles as a function of depth z (z-profiles) from the corresponding τ-profiles using inverse Laplace transforms. Application of the method to the residual strain vs τ data of Doerner and Brennan for an Al film on Si is presented.
Application of Imaging Plate for Polymer Analysis
Authors: Sasaki Katsunari , Kakefuda Kohji , Masuda Kenji , Hsiue Ging-Ho , Hsu Chain-Shu 
Published: March 2019

AbstractThe Fuji Imaging Plate (IP) is a 2-Dimensional X-ray detector on which a latent X-ray image is stored as a distribution of color centers in a photo-stimulable phosphor(BaFBr:Eu) screen. It has excellent characteristics such as a wide dynamic range of five or more digits and an order of magnitude higher sensitivity than X-ray film. Thus it has been actively used in the field of X-ray single crystal structure analysis.For polymer studies, 2-D information is useful to analyse a sample's orientation or periodic structure, and some system such as 2-D position sensitive detector (PSD) are widely used. But in spite of the superior performance of the IP which will give significant advantages in various measurements, few applications have been reported in this field, because most conventional IP based systems are specialized for the single crystal structure analysis,Therefore we developed the R-AXIS II D (Rigaku Automated X-ray Imaging System II D), an IP reader for general X-ray diffractometry which has a removable IP in order for exposure with external X-ray optics, and software which converts 2-D data to conventional 2theta-intensity or beta-intensity data for analysis of crystallinity or orientation. In this paper, we report the performance of R-AXIS II D and its applications to polymer studies and thin film analyses.
Determination of the Interaction Strains in Two-Phase Brass with X-Ray Diffraction
Authors: Noyan I.C. , Schadler L.S. 
Published: March 2019

AbstractDeformation in polycrystalline materials is highly inhomogeneous on a micro scale. This inhomogeneity arises from the anisotropy of the constituent grains, coupled with local configurational parameters such as texture, gram size or proximity to a free surface. In a recent paper, we had outlined a new method that extended the traditional x-ray stress analysis to yield quantitative measures of such inhomogeneous deformation. In this paper, this method is used to study the partitioning of inhomogeneous deformation between the phases of 60-40 brass tensile specimens subjected to applied loads.
RS/hyper: A Hypertext-Based Workstation for Reliable X-Ray Residual Stress Measurements
Authors: Ward A. , Hendricks R. W. , Brauss M. 
Published: March 2019

AbstractAdvances over the last ten years in computer automation and control, compact and portable x-ray sources, and reliable and efficient detector systems have allowed X-Ray Determination of Residual Stress (XRDRS) measurements to become a viable method of evaluating the state of stress in metals, alloys, and ceramics. However, problems associated with incorrect XRDRS equipment operation and poor experimental technique are prevelant in industry, necessitating better operator training and education. Therefore, an interactive computer workstation, called RS/hyper, was developed to lead the operator towards correct operating procedures and reliable experimental technique.Proper machine setup, machine maintenance, radiation safety, experimental technique, theoretical understanding, and limited data evaluation are presented in RS/hyper. Graphical aids are used extensively to avoid confusion and misinterpretation of theoretical concepts and equipment instructions. RS/hyper is interactive, allowing the user to learn about topics at a comfortable level of explanation. Compared to written texts and references, RS/hyper has been shown to reduce training and problem solving time by a factor of 16.RS/hyper will train novice users of XRDRS equipment so that the data acquired from such machines will be reliable in an industrial environment. Also, since the software educates the user, data will be more accurately represented before interpretation. The experienced user should find RS/hyper useful as a reference to XRDRS and related information.
X-Ray Elastic Constants of Sintered and HIP'ed ZrO2 Ceramics with Different Chemical Components
Authors: Sasaki Toshihiko , Kuramoto Makoto , Yoshioka Yasuo 
Published: March 2019

AbstractMechanical and X-ray elastic constants of four types of ZrO2 were measured for (133) planes with Cr-Kα radiation. The main differences among the specimens were the chemical components, the sintering method and the heat-treatment. It was found that the elastic constants were affected by the heat-treatment, but little by the other factors. The influence of the method of the peak determination on the result was also examined. The residual stresses at the knife edge were determined.
Asymmetric Diffraction with Parallel-Beam Synchrotron Radiation
Authors: Toraya Hideo , Huang Ting C. , Wu Yan 
Published: March 2019

AbstractIn this paper, the advantages and disadvantages of using the asymmetric 2θ scanning technique with a fixed incident angle α are described. Vertical-scan powder diffractometers with long horizontal parallel slits with an aperture of 0.05° and parallel-beam synchrotron radiation with λ = 1.54 Å and α = 10°, 2°, and 1° were used to collect α-Al2O3, silver behenate CH3(CH2)20COOAg, and Si powder diffraction patterns. The synchrotron radiation data were analyzed by profile fitting, and the results were compared with those obtained by the conventional θ-2θ scanning technique. As expected, significantly higher intensities were obtained from the asymmetric diffraction data with α = 10°. At smaller α = 2° and 1°, however, the intensities were reduced because of a smaller effective beam height. The peak positions remained practically unchanged for the data obtained with α = 10°, but displaced toward higher 2θ angles for α = 2° or lower, and, consequently a refractive-index correction was needed. Profile shape was slightly broadened and became more Lorentzian in asymmetric diffraction with highly oblique incidence of the beam. The change in shape was, however, negligibly small. The results showed that intensive and reliable powder diffraction data can be obtained from asymmetric diffraction by fixing the incident beam at a sufficiently large angle to fully illuminate the available sample surface.
Surface and Ultra-Thin Film Characterization by Grazing-Incidence Asymmetric Bragg Diffraction
Authors: Huang T. C. 
Published: March 2019

AbstractAn effective technique using grazing-incidence X-rays and asymmetric-Bragg diffraction (GIABD) for the characterization of crystalline phases on surfaces and structural depth-profiles in thin films is described. The application of the GIABD using both X-ray and synchrotron radiation sources for the analysis of an iron-oxide magnetic thin film previously reported to have an unexpected magnetically-dead layer is discussed. The X-ray diffraction analysis using the GIABD and the conventional θ-2θ scanning techniques detected an anti-ferromagnetic hexagonal α-Fe2O3 on the surface and a ferromagnetic tetragonal γ-Fe2O3 in the bulk of the film, respectively. The synchrotron diffraction analysis using incident angles below and above the critical angle of total reflection quantitatively determined the structural depth-profiles of α-Fe2O3 and γ-Fe2O3 in the film.
X-ray Examination of Fracture Surfaces of Silicon Nitride Ceramics
Authors: Yajima Zenjiro , Hirose Yukio , Tanaka Keisuke 
Published: March 2019

The residual stress left on the fracture surface is one of the important parameters in X-ray fractography. It has been used to analyze fracture mechanisms in fracture toughness and fatigue tests especially of iron and steels.In the present paper, X-ray fractography was applied to the brittle fracture surface of a silicon nitride ceramics. The first part deals with the determination of the stress constant for diffraction from Si3N4(411) plane by Cr-Kα radiation. The second part describes the effect of the notch-tip radius on the fracture toughness value. In the last part, the plastic zone depth was determined from the residual stress destribution beneath the fracture surface.
The Importance of Consistent 1/d Scans in Determining Size and Strain by Powder Diffraction Profile Analysis
Authors: Zhang Y. , Stewart J. H. , Hubbard C. R. , Morosin B. 
Published: March 2019

AbstractThis paper reports and discusses the results of a computer modeling study on powder diffraction profile analysis for crystallite size and strain of polycrystalline materials. The results of this computer modeling show that if the spans of diffraction profiles in reciprocal space (1/d) are not carefully chosen, an overestimation on size and an underestimation on strain may result in analysis by both the Warren-Averbach and the Hall-Williamson methods. A general way to eliminate such errors based on profile fitting and regeneration is presented and discussed in this paper.
XRF Technique as a Method of Choice for On-Site Analysis of Soil Contaminants and Waste Material
Authors: Piorek Starislaw 
Published: March 2019

AbstractRecent years were marked by a rapid increase of interest in the ase of x-ray fluorescence for on-site chemical characterization of contaminated soils and waste materials.The known advantages of the XRF technique, such as capability of simultaneous, multielement analysis, speed of measurement (10 to 100 seconds), little or no sample preparation, wide concentration range, “portability,“ and ease of integration into environmental monitoring station(s), make it specifically suited for this application.Major difficulties still inhibiting wider use of the XRF for hazardous waste screening stem from the lack of suitable calibration samples and proper protocols, as well as from the low awareness of the industry about the technique.
Microvolume Analysis of Fly Ash by Synchrotron Radiation X-ray Fluorescence (SRXRF) and Electron Microprobe X-ray Microanalysis (EPXMA)
Authors: Török Sz. , Sándor Sz. , Rausch H. 
Published: March 2019

The assessment of the potential environmental and toxicological effects of particulate material emitted to the atmosphere requires detailed physical and chemical characterization of the particles. One of the most widely studied types of pollutant particles is coal fly ash as a byproduct of coal combustion. These particles are inhomogeneous, highly variable, span a broad range of sizes and have diverse morphologies.It has been shown that numerous toxic trace elements tend to increase in bulk concentrations with decreasing particle size (1).
An Improved Fusion Technique for Major-Element Rock Analysis by XRF
Authors: Couture Rex A. 
Published: March 2019

AbstractA new apparatus and technique are described for borate flux fusion of rocks for x-ray fluorescence analysis. The method yields homogeneous, strain-free glass discs with flat, smooth surfaces that do not require polishing. The technique is adapted from several previous methods but has advantages over each in terms of sample uniformity, quality of the discs, or capital cost. The ignited rock powder is fused with flux over a burner mounted on a stock laboratory mixer, and is cast into a solid flat, polished Pt-Au mold. The very effective mixing action ensures homogeneity An oxidizing atmosphere, which is necessary to prevent loss of iron to the crucibles, is maintained by injecting air during fusion.There is no significant loss of alkali metals during fusion, and negligible loss of flux. Duplicate samples of several rock types show excellent reproducibility, approaching counting statistical errors, for 10 major elements.
X-ray Diffraction Studies of Polycrystalline Thin Films Using Glancing Angle Diffractometry
Authors: Larsen R.A. , McNulty T.F. , Goehner R.P. , Crystal K.R. 
Published: March 2019

AbstractThe use of conventional θ/2θ diffraction methods for the characterization of polycrystalline thin films is not in general a satisfactory technique due to the relatively deep penetration of x-ray photons in most materials. Glancing incidence diffraction (GID) can compensate for the penetration problems inherent in the θ/2θ geometry. Parallel beam geometry has been developed in conjunction with GID to eliminate the focusing aberrations encountered when performing these types of measurements. During the past yearwe developed a parallel beam attachment which we have successfully configured to a number of systems.
Vacuum Free-Fall Method for Preparation of Randomly Oriented XRD Samples
Authors: Ludlam Jim , Jacobs Brad , Predecki Paul K. 
Published: March 2019

Quantitative phase analysis by XRD requires the attainment of (1) random crystallite orientation and (2) homogeneous and intimate mixing of the constituent phases in the samples. These two requirements must also be met in the preparation of random composite materials, particularly those containing randomly-oriented fibers or whiskers.The two most common methods for producing random crystallite orientation are spray drying and the air suspension method. In the latter, an air suspension of the crystallites is rapidly collected onto a glass fiber filter. The crystallites then assume the random orientation of the filter fibers on which they are deposited.