bluuebunny/crossref_metadata_2025 huggingface dataset:
Some Applications of a Computer-Controlled X-Ray Spectrometer in a Steel Research Laboratory
Authors: Harter W. T.
Published: March 2019

The U. S. Steel Research x-ray spectrometric laboratory performs between 7,000 and 10,000 analytical determinations each month for alloying elements in all types of steels and raw -materials. The spectrometer is automatically controlled by a DEC PDP 8/1 minicomputer utilizing vari ations of software packages provided by Siemens Corporation. As many as 256 individual analytical measurements can be sequentially performed. The minimal interelemental effects encountered in low-alloy steel analyses are corrected in a separate program written in FOCAL language. Correction coefficients for the program were established by multiple linear regression analyses.

Stainless and multialloy steels are analyzed with a two-part control and correction program. The control program controls all functions of the spectrometer automatically and stores parabolic calibration coefficients. Following a sequential determination of the alloying elements control is switched to a correction program written in FOCAL. The correction program prints a tabular listing of the elements determined, followed by a listing of the corrected concentrations of elements adjusted for interelemental effects. Orthogonal polynomial analyses were performed to determine σ values for all constituents determined.

For analysis of raw materials, the samples are fused prior to analysis by use of a flux and heavy absorber technique that essentially eliminates interelement effects and permits linear calibrations up to 100 percent. Samples are ground and pelletized after fusion for better reproducibility. Single sets of calibration standards are used regardless of raw materials mineralogical history. Synthetic standards can be produced for ranges where no calibration standards exist.
Energy Dispersive X-Ray Fluorescence Spectrometry Using Pulsed X-Ray Excitation
Authors: Jaklevic J. M. , Landis D. A. , Goulding F. S.
Published: March 2019

An energy dispersive X-ray fluorescence spectrometer using pulsed X-ray excitation has been developed for use in large-scale environmental analysis programs. A grid controlled X-ray tube is coupled with variable secondary fluorescence targets to analyze for a wide variety of elements with almost optimum sensitivity. The operation of the pulsed tube in a feedback loop with the semiconductor detector spectrometer results in a substantial increase in output counting rates without pile-up. The loop functions by turning off the excitation immediately upon detection of an event by the spectrometer. Pileup events are virtually eliminated and the X-ray tube's available anode power is better utilized.

The electronic control of this feedback mode results in some unique features in the response of the system to varying sample mass. These features are discussed in detail. Experimental results for sensitivity and accuracy over the range of elements measured are presented. Early operating experience with the unit indicates increases of counting rates of a factor of five compared with similar conventional systems.
The Use of Proton-Excited X-Ray Emission to Study: 1) Electrodeposited TiB2 Coatings and 2) Gas-Turbine Blade Failures
Authors: Sartwell B. D. , Needham P. B.
Published: March 2019

A method to quantitatively analyze the surface regions of metals, alloys, and coatings using proton-excited X-ray emission (PEX) has been utilized in two areas of metallurgy research. This paper describes application of the technique to (1) the development of erosion- and corrosion-resistant coatings, and (2) the study of structural failures in turbine alloys.

The technology for the electrodeposition of erosion- and corrosionresistant TiB2 coatings from molten-salt electrolytes has been developed in order to provide protective coatings for valve components in coal gasification plants. Analyses by PEX and X-ray diffraction have played the key role in the determination of the optimum electrolysis parameters required to obtain adherent, erosion-resistant TiB2 coatings. From these studies, the erosion resistance of a TiB2 coating can be predicted on the basis of (1) the amount of Cr and Fe impurities codeposited during electrolysis and (2) the degree of orientation of the TiB2 crystal structure along the (110) or (100) planes.

PEX was used for analytical studies of a Nimonic 105 alloy turbine blade and an A-286 alloy turbine wheel from a San Diego, California, power generating station gas turbine that suffered a catastrophic failure in November 1974. Analyses of the turbine blade in the region at which the rupture occurred showed alloy composition changes that included decreases of 80%, 78%, 52%, and 50% of Al, Ti, Cr, and Co, respectively, and an increase of 2500% in Fe. Alloy composition changes were also found at the failure interface of the turbine wheel; these included decreases of 43%, 21%, and 15% in Hi, Cr, and Ti, respectively, and increases of 248% and 714% in Si and Al, respectively.
Sulfur Analysis of Air Pollution Samples Containing Sulfuric Acid with a Vacuum X-Ray Fluorescence Spectrometer
Authors: Knapp K. T. , Bennett R. L. , Kellogg R. B.
Published: March 2019

Vacuum x-ray fluorescence spectrometers are used routinely in our laboratory to analyze automotive exhaust particulate emissions. However, a problem has developed in the analyses of samples collected from cars equipped with catalytic converters. The catalytic converters which were developed to decrease the carbon monoxide and unburned hydrocarbon emissions from auto exhausts, also produce sulfuric acid through the oxidation of part of the SO2 emissions. The sulfuric acid aerosol which is collected with the particulate emissions causes problems in the use of a vacuum spectrometer. If the samples are analyzed as , collected, the sulfuric acid would be pumped off the collection filters resulting in the loss of sulfur from the samples and contamination of the spectrometer. A technique was needed to fix the sulfuric acid so that it would remain on the filters. Exposure of the samples to ammonia gave the needed stability. Details of the technique in cluding standard preparation procedures are described. The results obtained with samples exposed to ammonia at various concentrations and periods of time are presented.
Enrichment Procedures for Water Analysis by X-Ray Energy Spectrometry
Authors: Van Grieken R. , Bresseleers K. , Smits J. , Vanderborght B. , Vanderstappen M.
Published: March 2019

Energy-dispersive X-ray fluorescence might advantageously be used for the determination of trace metals in water. Suspended material can straightforwardly be collected on a 0.45 μm pore-size Nuclepore membrane by filtration. Dissolved ion analysis usually requires a physical or chemical enrichment step. Spotting a 1.5 ml water sample on a Whatman-41 filter within a 29 mm diameter hydrophobic ring and drying by a cold air stream from underneath yielded a 50 ppb sensitivity for many elements, and a 18% accuracy. Filtration of a 200 ml water sample at the natural pH through a pair of Chelest-100 chelating ion-exchange resin loaded filter papers allowed 1-5 ppb sensitivities but suffered from the combination of limited load capacity and significant uptake of usually abundant alkali earth metals.
Calibration and Correction Methods for Quantitative Proton-Induced X-Ray Emission Analysis of Autopsy Tissues
Authors: Nielson K. K. , Hill M. W. , Mangelson N. F.
Published: March 2019

Methods have been developed for autopsy tissue analysis using a proton-induced X-ray emission (PIXE) system optimized for thin sample analysis. The system uses 2 MeV protons, thus limiting sample thickness to several milligrams per square centimeter. Calibration was accomplished with standard solutions spotted onto Nuclepore filters, which were subsequently irradiated in a uniform proton flux. X-ray yields measured with a Si (Li) detector were corrected for proton energy loss in the filter matrix as well as X-ray attenuation. Corrections for proton energy loss were determined from empirical parameters relating proton energy to X-ray cross sections. Typical filter thickness and penetration of the sample solution into the filter matrix were measured allowing calculation of proton energy attenuation and X-ray absorption corrections. The method was used in routine analyses for sixteen elements in seven types of human tissue. Accuracy was evaluated with standard reference materials and atomic absorption analyses.
Theory & Performance of Holographically-Formed Stigmatic X-Ray Gratings
Authors: Speer R. J.
Published: March 2019

Holographically-formed X-ray reflection grating scan now be constructed with competitive groove efficiency to classically ruled types, down to a short wavelength diffracting limit of several angstroms.

The gratings can be generated on any surface capable of intersecting the interference fringe pattern without shadowing. This fact alone brings several new X-ray optical design possibilities within reach, for example, by combining plane construction waves with steep aspheric substrates. The first order imaging theory of the grazing incidence mounting is discussed and compared to measured performance for aberration corrected stigmatic types.

A new 5 meter spectrograph has also been constructed with applications in molecular chemistry, laser fusion
research and synchro tronspectroscopy. The unit is available with fully prefocussed holographic and classical
X-ray grating optics, and uses the precision miniature camera principle of fully interchangeable lenses, but applied, in this case to the entrance slit, grating and detector modules.
Effect of Milling on the Crystal Structures of Chrysotile and Other Serpentine Minerals
Authors: Charola A. E. , Lewin S. Z.
Published: March 2019

The most prominent peaks of chrysotile are the 002 and 004 reflections, and in dilute mixtures of chrysotile in talc they are the only peaks that can be detected. Milling of chrysotile markedly reduces these peak heights and areas, and generates a new, sharp peak at d = 2.52 A. Milling of other serpentine minerals also results in line broadening and integrated intensity decrease of the 002 and 004 lines; a weak d = 2.52 reflection is initially present and milling causes this to increase slightly in intensity, without any detectable line broadening. The variations in relative intensities of these peaks for different size-classified fractions of the several minerals after prolonged milling confirms that the d = 2.52 A reflection is due to a phase that is different from the starting material. Investigation of specimens held at various temperatures up to 1000°C shows that the consequences of milling cannot be attributed to local heating effects. It is confirmed that chrysotile is readily attacked and dissolved by 1 M HCl, whereas the other serpentine minerals are relatively inert to this reagent. In the case of extensively milled chrysotile, the acid treatment causes the 002 and 004 peaks to weaken and eventually disappear, but the d = 2.52 A peak remains unaffected.
The Application of a Position-Sensitive X-Ray Detector to the Measurement of Residual Stresses
Authors: James M. R. , Cohen J. B.
Published: March 2019

In recent years considerable success has been achieved in the development of detectors for the localization of ionizing radiation. One dimensional position sensitive detectors have a number of uses in nuclear physics and in biological studies utilizing small-angle scattering. Detectors are now capable of providing position information of high resolution with a high count rats capability and a simple readout system. We report here on the feasibility of employing a position sensitive proportional counter (PSPC) for the measurement of residual stresses with X-rays.

Comparisons of the accuracy and time of data accumulation between a scintillation detector and a PSPC have been performed on stress relieved, shot peened steel specimens, and specimens deformed in tension.

The ability of obtaining the entire profile at once is somewhat offset by the lower efficiency of the PSPC when compared to a scintillation detector, but this is counteracted by the fact that motion of the detector is eliminated with the PSPC, It will be shown that a PSPC system provides a speed of data accumulation currently not available in any other way, while still remaining a versatile and accurate method.
Indexing Powder Diffraction Patterns
Authors: McLachlan Dan , Chen Sylvia
Published: March 2019

Despite the fact that the many researchers, who have worked on the problem of indexing powder diffraction patterns, have made several important advances in the field and have proven in theory at least that any pattern can eventually be indexed, the procedures are frequently so laborious as to drive the investigator to despair. Starting with the knowledge that convolution functions and particularly self-convolutions ﹛so well known to crystallographers as Patterson functions) have the power to find the distances between points in space, and knowing that reciprocal space is filled with repeating distances, the present authors have evolved a graphical system for carrying out the previously discovered procedures in an easy and rapid manner.
On the Determination of Preferred Orientation in Ferritic Steels
Authors: Slane John A. , Hultgren Frank
Published: March 2019

A new approach to the analysis of preferred orientation in body centered cubic sheet materials is presented. The technique utilizes normalized extended inverse pole figures (2θ = 16 to 150°) taken in the plane normal, rolling, and transverse directions. Possible texture components are defined to be all unique sets of three mutually orthogonal crystallographic planes included in the diffraction pattern up to 150° 2θ for a total of 56 possible components. A computer program has been developed to calculate the contributions of various texture components relative to the three principal directions by two computer implemented algorithms, probability and successive decrementation. The two methods exhibit an apparent high correlation.

The calculated results are compared to monochromated direct pole figures for a highly textured material. The agreement is excellent.
The Effect of Surface Oxide on the Changes in the FeLII/LIII Ratio with Accelerating Voltage
Authors: Holliday J. E.
Published: March 2019

Measurements have been made on the FeLII/LIII intensity ratio on oxide free iron surface produced by evaporating a 50 Å Ti film on iron. These results show that the reported increase in the FeLII/LIII ratio with decreasing accelerating voltages is due largely to surface oxide and not self absorption. Also, for the vacuum presently used by soft x-ray spectroscopists the oxide surface on metals contribute strongly to the soft x-ray spectra of the bulk material for accelerating voltages below 4 kV.
Chemical Bonding Effects in X-Ray Emission Spectra - A Molecular Orbital Model
Authors: Urch David S.
Published: March 2019

Molecules or ions usually exist as discrete units, in crystals of chemical compounds. Intermolecular or interionic coValent interactions are slight so the bond structure of such, solids is very similar to the pattern of energy levels in each individual molecule or ion. Simple molecular orbital theory can therefore be used to generate a qualitative picture of the energy levels in a molecule or an ion; and this picture can then be used directly to interpret X-ray emission spectra. The application of molecular orbital theory, using group theory to simplify the calculations is described for a tetrahedral unit ML4. The origin of peak shifts and of low-energy satellite peaks are rationalised. A consideration of orbital amplitudes shows that the ‘cross-over' theory of O'Brien and Skinner cannot explain the observed intensities of low-energy satellite peaks. It is suggested that the use of the M. 0. model for the interpretation of X-ray emission spectra permits far greater analytical and structural use to be made of peak shift and satellite data. Ligands can be identified even when their own characteristic emissions are not detected (e.g. oxygen and fluorine). Relative peak intensities can be correlated with atomic orbital participation in bond formation. Such information is of great interest to chemists and can often be used to identify the bonding r61e of specific orbitals (e.g. the 3d orbitals of second row, main group, elements).
Systematic Errors in X-ray Diffractometer Stress Measurements Due to Specimen Geometry and Beam Divergence
Authors: Zantopulos Harry , Jatczak Chester F.
Published: March 2019

A method is described for determining the magnitude and sense of systematic errors in x-ray diffractometer stress measurements produced by focusing aberrations during diffraction from imperfect specimen contours and wide horizontal beam divergences. Corrections for such systematic errors are presently not made. However, if the highest accuracy and/or absolute values of stress are desired, these must be either taken into account or minimized by control of beam geometry. Equations and computer data are presented to indicate the errors in 2θ and stress (σ) resulting from use of flat, various convex and concave curvatures for primary beam divergences of 1° to 3°, Stress errors are calculated for both the parafocus technique of beam focusing and the stationary or non-focusing method.

The results show that convex and flat specimens always produce negative 2θ deviations from the condition of perfect focus and thus a net positive or tensile stress error. The magnitude of this error increases as the radius of the convex shape decreases and/or the ψangle and beam divergence is increased. Concave specimens with curvatures less than the radius of the concave shape required for perfect focus (see body of report) produce positive 2θ deviations and, therefore, negative or com-pressive stress errors.

The stationary or non-focusing technique produced systematic errors which were 1/3 of those produced by focusing aberrations with the parafocus technique. Fortunately, in both cases the actual errors are not very large (less than ±7.5 ksi), even with divergent beams as large as 3° and convex radii as small as 125”.
Crystal Distortions Associated with Magnetic Ordering in the Antiferromagnetic Compound VF2
Authors: McCain W. S. , Albright D. L. , Boo W. O. J.
Published: March 2019

Lattice constants were measured as a function of temperature by single crystal diffracrometry in the temperature range which includes the Néel temperature of VF2(TN= 7°K). The lattice constants of VF2(D4h14=P42m n m) were measured from room temperature down to 4.2°K. In this range rhe tetragonal c-axis contracts 0.58% from 3.2359 Å (RT) to 3.2170 Å (4.2°K). On the other hand, the a-axes show a net expansion of 0.18% from 4.8023 Å (RT) to 4.8110 Å at 4.2°K. The temperature dependence of the lattice constants can be correlated with anisotropy of exchange forces. Vanadium Ions occupy the center and corner positions of the unit cell. Strong magnetic interactions are directed parallel to the c-axis >001< with considerably weaker interactions parallel to the body diagonals >111< The relative strengths of the two exchange integrals are J >001< = 50 J >111<. As a consequence the magnetic ordering is one-dîmensional along the c-axis and the associated distortions arise from the strong magnetic interactions along this axis.
Calculated Patterns in X-Ray Powder Diffraction Analysis
Authors: McCarthy Gregory J. , Martin Kyli J. , Holzer Jean M. , Grier Dean G. , Syvinski Wayne M. , Nodland Darred W.
Published: March 2019

Calculated patterns play an essential role in X-ray powder diffraction analysis. This paper gives examples of their use in qualitative analysis for evaluating and supplementing reference patterns in the ICDD Powder Diffraction File (PDF), in quantitative analysis for calculating Reference Intensity Ratios (RIRs), in ceil parameter refinements for indexing of low-symmetry/large unit cell diffractograms, in powder pattern determination for validating intensities and recognizing preferred orientation, in new materials synthesis for verification of structure type and phase purity, and for modeling the effects of solid solution substitution.
Rietveld Analysis and Pair Wise Substitutional Alloys
Authors: Kaplan Wayne D. , Kimmel Giora
Published: March 2019

Rietveld Analysis on X-Ray powder diffraction data was used to build a comprehensive model of the structures in gallmm rich R-Ga systems (R is a rare earth between La and Gd). The ability to refine occupation factors as well as atomic positions allowed for the analysis of the e solid solution, its structural relation to the ordered ∊′ phase, and the unique role of the Ga-Ga pairs in these systems.
The Effects of Sampling Error on Detection Limits Determined for Quantitative X-Ray Diffraction
Authors: Raab Gregory A. , Dalheim Peggy
Published: March 2019

This paper investigates the contributions of sample preparation to the analytical lower limits of detection and errors for the quantitative X-ray diffraction analysis of a simple, binary system of quartz and calcite. This study further demonstrates the danger of using only statistical and instrumental contributions to detection limits and analytical errors.
Determination of Crystal Structure and Cation Distribution in Thin Films
Authors: Will G. , Huang T. C. , Sequeda F.
Published: March 2019

The structural characterization of thin films is important for research development and manufacturing of electronic, magnetic, optical, and other high-tech materials. The grazing incidence X-ray diffraction technique has bean used successfully for the determination of crystalline phases, structural-depth profiles, crystallite size, and strain, etc. of thin films with thickness's down to a few tens of Å, If the crystal structure, e.g. the distribution of atoms in the unit cell, or the crystallinity and texture (or preferred orientation) of a film is of interest, the conventional Bragg-Brentano diffractometer technique with the θ-2θ scanning geometry has been found to be appropriate.
Prediction of the Diffraction Order Dependence of the Integral Reflection Coefficient of Multilayer Structures using Atomic Force Microscope Measurements
Authors: Brown D.B. , Konnert J.H. , Gilfrich J.V. , D'Antonio P. , Freitag R.K. , Rosenstock H.B. , Burkhalter P.G.
Published: March 2019

The evaluation and understanding of the x-ray diffraction properties of multilayer structures is critical in predicting the degree of success in their utilization in x-ray optics applications. A key material parameter affecting the diffracting efficiency of multilayer structures is the roughness of the interfaces between the deposited layers. This paper will use measured roughness to predict the integral reflection coefficient as a function of diffraction order for several multilayer structures.

We have made atomic force microscope (AFM) measurements of the detailed displacement distribution for me surface roughness of W/C and W/Si multilayer structures. This information has been introduced into a theoretical model to predict the reduction of the integral reflection coefficient induced by surface roughness. In a fashion analogous to the Debye-Waller factor, this reduction in diffracted intensity is predicted to be strongly dependent on the diffraction order. These predictions have been compared with experimental integral reflection coefficient data. The measured diffraction results indicate a greater reduction in reflection than is predicted by the AFM measurements. A possible explanation for this discrepancy is that the AFM measurements underestimate the roughness. Possible reasons for the differences between these methods will be discussed.
A Simple Setup for Glancing Angle Powder Diffraction with a Sealed X-Ray Tube
Authors: Georgopoulos P. , Levine J.R. , Chung Y.W. , Cohen J.B.
Published: March 2019

The pioneering work of Marra, Eisenberger and Cho (1979) demonstrated that powder diffraction from near surface and interfacial regions could be obtained using glancing incidence geometry. This has generated considerable interest in research at synchrotron sources, but also several slit attachments have been developed for commercial diffractometers. By adding a focussing mirror, we demonstrate here a simple arrangement that produces adequate intensity with a sealed tube to examine ultra thin films.
Synthesis Analysis of Thin Films by XRD and SEM
Authors: Fujinawa Go , Tobe Shogo
Published: March 2019

This is a report of an investigation by XRD and SEM of thin coatings such as are applied by plasma spray methods for improving properties, such as are wanted in electronic devices, and for increasing durability in service. Samples were studied that had been coated under controlled conditions: Physical Vapor Deposits (PVD) of titanium nitride on steel plate and plasma spray coatings of molybdenum on steel plate. X-Ray determinations were made of x-ray lattice constants, crystallite size, lattice strain, orientation and residual stress, before and after strain was applied to the specimens.
Investigation of Semiconductor Heterostructures by White Beam Synchrotron X-Ray Topography in Grazing Bragg-Laue and Conventional Bragg Geometries
Authors: Yao G.-D. , Wu J. , Fanning T. , Dudley M.
Published: March 2019

White beam synchrotron X-ray topography has been applied both to the characterization of two semiconductor heterostructures, GaAs/Si and InxGa1-xAs/GaAs strained layers, and a substrate to be used for growing semiconductor epilayers, Cd1-xZnxTe. In the case of the heterostructures, misfit dislocations were observed using depth sensitive X-ray topographic imaging in grazing incidence Bragg-Laue geometries. The X-ray penetration depth, which can be varied from several hundreds of angstroms to hundreds of micrometers by rotating about the main reflection vector, which in this specific case was (355), is governed by kinernatical theory. This is justified by comparing dislocation contrast and visibility with the extent of the calculated effective misorientalion field in comparison to the effective X-ray penetration depth. For the case of Cd1-xZnxTe, twin configurations are observed, and their analysis is presented.
Powder Diffraction Data Correction: Single-Crystal Standards and Fourier Asymmetric Component Stripping
Authors: Briden Frank E. , Snoddy Richard B.
Published: March 2019

The need for reliable standards for the characterization of x-ray powder diffraction (XRD) instruments has been well documented. As a result of the round robin study, of various candidate standard materials, described by Fawcett et al., the National Institute of Science and Technology has made the SRM-660, lanthanum hexaboride, XRD peak width standard available. It has been normal practice to use powder sample standards for XRD powder diffraction studies. Powder standards have been justified on the principle that standards should be as much as possible like the unknowns to be analyzed; however, standards must be quite different from the unknowns because their peak profiles must be as narrow as possible for deconvolution from sample peak profiles. It would seem most advantageous to use standards of the highest degree of crystallinity so that they would be useful over the maximum number of applications. Single crystals, with their extremely high crystallinity, offer that advantage.
Construction of a Multimode High Resolution X-Ray Powder Diffractometer and its Perfomance
Authors: Kurahashi Masayasu , Honda Kazumasa , Goto Midori , Inari Yu , Katayama Chuji
Published: March 2019

Recently some of the above authors determined the structure of an unsolved organic compound employing X-rays from a Synchrotron, an Imaging Plate, and a large radius camera. It would be more desirable if the high quality powder diffaction data could be obtained by a diffractometer or a camera of laboratory use. Therefore a multimode X-ray powder diffractometer which can be used for various experimental geometries such as Bragg-Brentano mode, Guinier mode and parallel beam mode was constructed in order to find the highest resolution geometry. In this paper wc present the results of the measurements employing these three modes.
Chemical State Analysis using a Gearless Two-Crystal X-Ray Spectrometer
Authors: Konishi Tokuzo , Nishihagi Kazuo , Taniguchi Kazuo
Published: March 2019

A two-crystal spectrometer for chemical state analysis by high-resolution x-ray fluorescence spectrometry employs hall-screw and slide mechanisms rather than gears to obtain a 2θ scanning range of 40° -147°; a Δ2θ scanning step of 10−4 deg under vacuus; a 2θ resolution of 10−4 deg in determination of an intercrystal angle with encoder-based measurement; and servomechanical control of position. The spectrometer, although simple in structure, is a powerful instrument for chemical state analysis, as demonstrated by its high resolution, precision, and stability; as demonstrated in the determination of the Kα1 lines of first transition metals with Si(220) as analyzer crystal, and in its application to a systematic study of the chemical effects on Ni Kα1 and Kα2.
Time-Resolved Observations of Solid Reactions and Structure Transitions using a PSD, An SSD and Computer Aided Measurement and Control
Authors: Yamanaka Takamitsu , Kawasaki Shinji , Shibata Tsuyoshi
Published: March 2019

For time-resolved diffraction studies under high temperature and/or high pressure, we designed a new diffractometer incorporating a curved position sensitive detector and tested the rapid intensity measurement and the resolution of the angular dispersive diffraction. The diffraction profiles were compared with those from energy dispersive diffraction. Rapid intensity collection has been carried out with a CAMAC module. A curved position sensitive detector with a 120° working angular region was installed on the off-centered four circle diffractometer. Only a few seconds were needed to obtain a whole powder diffraction because of the extremely high counting efficiency due to the streamer mode.

Time-resolved observations of the dehydration reactions of Mg(OH)2 and Ca(OH)2, have been undertaken by angular dispersive and energy dispersive x-ray powder diffraction at high temperature. The in situ observations of the dehydration process provide kinetic information, such as the reaction rate, the apparent activation energy and the dehydration mechanism.
Determining Stresses in Composites
Authors: Cohen J. B.
Published: March 2019

The basic diffraction techniques for examining the stress tensor are reviewed, with particular emphasis on what can be done without knowing the unstressed lattice parameter(s). Examples are given of the residual stresses in thin films, how to measure the bonding and yield stress in composites and separating the micro and macrostresses to examine load sharing between phases.
Young's Modulus Measurement of Chromium Electroplating
Authors: Ohtsuka Masaaki , Hatsuok Hideaki , Hirose Yukio , Ishii Hitoshi
Published: March 2019

The electroplating of Cr has been an important industrial process for cutting tools, press machines and molds for casting. In spite of these, quite a few problems remain unsolved regarding the basic property. It is important to know the mechanical characteristics of Cr electroplated layers.

In the present paper, the first part deals with the measurement of mechanical Young's modulus of Cr electroplated layers. The X-ray method was successfully applied to measure the X-ray Young's modulus and the residual stress on the Cr electroplated surface layer.
The Application of X-Ray Diffraction Method to the Measurement of Crystal Deformation and Crystal Modulus of High Polymers
Authors: Nakamae Katsuhiko , Nishino Takashi
Published: March 2019

Elastic modulus EI of crystalline regions of various high polymers in the direction parallel to the chain axis were measured using an X-ray diffraction method. The crystal deformation can be detected directly by the diffraction peak shift as a function of applied constant stress. The stress in the crystalline regions is assumed to be equal to that applied to the specimen. The validity of this assumption has been proven experimentally for polyethylene, poly(p-phenylene terephthalamide) and so on. The EI values were discussed in relation to molecular conformation and deformation mechanism of the chains.
Analysis of X-Ray Diffraction Data for the Characterization of Residual Stress
Authors: Park Jun S. , Shackelford James F.
Published: March 2019

The analysis of linear dϕψ vs sin2ψ x-ray diffraction data in isotropic single phase materials was investigated for the evaluation of x-ray elastic constants. This study developed an experimental model for estimating x-ray elastic constants based on the analysis of biaxial residual stress states, A ball bearing steel and a 1018 steel weldment were evaluated.

In a second study, the measurement of residual stress gradients was evaluated for those depth ranges mat can not be evaluated with a single radiation. This requires various planes and radiation energies to obtain the simultaneous conditions of high diffraction angle and large x-ray penetration depth. The evaluation of the overlapped stress gradient region is illustrated in terms of x-ray energy and diffraction angle for the ease of iron. This analysis is specifically developed for the purpose of stress gradient measurement using synchrotron radiation.
Characterization of Ferroelectric PZT Thin Films - Line Broadening Study (Using Grazing Incidence Geometry)
Authors: Eatough Michael O. , Goehner Raymond P. , Headley Thomas J. , Tuttle Bruce A.
Published: March 2019

Ferroelectric polycrystalline thin films are being pursued as materials for use in the next generation of radiation hardened nonvolatile semiconductor memories, optical switches and optical computers. Of particular interest are PZT films with a composition near the morphotropic phase boundary. In order to fully understand the the difference in electrical properties as a function of processing parameters it is necessary to fully characterize phase composition and crystallographic properties of these films. Since some films are produced by either spinning or dipping successive layers to obtain the desired thickness it was necessary to compare the properties of each layer.

X-ray diffraction techniques employing parallel beam optics with grazing incidence angle geometry were used to characterize the films. Experimental procedures using sealed tube xray diffraction systems to determine differences in crystallite size and microstrain as a function of depth into the films are a rather unique application of this technique. Discerning the contribution to line broadening due to phase changes, grazing incident angle geometry, crystallite size and microstrain are key to the success of this technique.

This paper discusses the experimental techniques employed and will demonstrate how we were able to successfully determine microstrain as a function of depth into the film. We use transmission electron microscopy (TEM) to aid in the characterization of the films. A brief description of the processing procedures used to produce the films is also provided.
Numerical Calculation of Axial Divergence Profiles
Authors: Coyle R. A.
Published: March 2019

The diffractometer instrumental profiles convoluted by Alexander from aberration profiles calculated using the methods developed Easterbrook, Pike and Wilson include two profiles which are not amenable to exact analytical solution. These two profiles are generated by the axial divergence and flat specimen aberrations. Using ray tracing techniques the exact profiles of these two aberrations have been computed for the Philips PW1050 and Scintag DA5 diffractometers. sample profiles at 2θ = 28°, 90° and 152° have been convoluted with the third asymmetric profile, that due to specimen transparency, and plots of the resultant profiles are shown. Shifts of the centroids and the peaks of the profiles from the true Bragg angle have also been computed and plotted over the range 2θ = 0°-180°.
Oxidation/Reduction Melting Equilibria in the System BaO-½Y2O3-CuOx II. Powder X-Ray Analysis
Authors: Wong-Ng Winnie , Cook Lawrence P.
Published: March 2019

X-ray powder diffraction together with several other analytical techniques have been used to characterize the phase formation and the melt compositions associated with the invariant reactions in the system BaO-½Y2O3-CuOx. In this report, the characterization results of the ternary eutectic reaction of the system, the melting of the high Tc compound Ba2YCU3O6+x, and the melting of the 'green phase' BaY2CuO5 are described. The minimum malting eutectic temperature of the system has been determined to be ≈ 925°C, which corresponds to the reaction of Ba2YCu3O6+x + CuO + BaCuO2 → Liquid. The melting of Ba2YCu3O6+x takes place at around 1015°C to yield BaY2CuO5 + Liquid. The green phase melts around 1270°C to yield BaY2O4, Y2O3 and liquid. All these melts were found to contain only a small amount of Y. Reduction of the copper was found to accompany melting.
Probing Structure-Property Relationships in a Family of Aryloxyphenoxy Propionate Herbicides Using Single Crystal X-Ray Diffraction Techniques
Authors: Rudolf Philip R. , Kershner Larry , Tai Jim
Published: March 2019

Aryloxyphenoxy propionates are a widely manufactured class of highly active grass-selective herbicides for use in various crops. Examples include VERDICT (1a), FUSILADE (1b), WHIP (1c), and ASSURE (1d). Figure 1 shows the general structure of aryloxyphenoxy propionates. All of these compounds contain a chiral center and each enantiomer of the optical pair exhibits significantly different herbicidal activity. The optically active isomers can be prepared by reacting the corresponding substituted phenoxyphenol with the S-(-)methyl lactate sulfonate ester (2). However, the optical yield from this type of reaction is usually less than 85%. Optical purification can be achieved by control of the crystallization.
“Whole Pattern” XRD Interpretation of Mineralogical Variation
Authors: Ferrell Ray E. , LaMotte Lynn R. , LeBlanc Wanda S. , Wilensky David E. , Mao Lin
Published: March 2019

All intensity data in a powder XRD pattern can be used to provide useful results for the interpretation of the mineralogical variability of geological samples. Simple statistical methods using Bonferroni's theorem permit the recognition of areas usually associated with mineral peaks where sample patterns are different at a predetermined level of confidence. Intensity/frequency histograms reveal subtle differences in low intensity regions of the XRD patterns that are also indicative of sample variability. These procedures facilitate the comparison of samples and may reduce the total analytical error because the weight percent determination can be eliminated.
The Gas Proportional Scintillation Counter as a Room-Temperature Detector For Energy-Dispersive X-Ray Fluorescence Analysis
Authors: Conde C. A. N. , Requicha Ferreira L. F. , Campos A. J. de
Published: March 2019

A review of the basic physical principles of the gas proportional scintillation counter is presented. Its performance is discussed and compared with that of other room-temperature detectors in regard to applications to portable instruments for energy-dispersive X-ray fluorescence analysis. It is concluded that the gas proportional scintillation counter is definitely superior to all other room-temperature detectors, except the mercuric iodide (HgI2) detector. For large areas or soft X-rays it is also superior to the HgI2 detector.
Volatilization of Sulfur in Fusion Techniques for Preparation of Discs for X-Ray Fluorescence Analysis
Authors: Baker James W.
Published: March 2019

The fusion technique for sample preparation for x-ray fluorescence analysis has been proven very successful for a wide variety of sample types. An inherent problem in the fusion technique has been the loss of sulfur during the fusion process. To extend our quantitative major element analysis method for geologic materials we have examined the problem of sulfur volatilization and have tested a variety of fluxes to determine their suitability to quantitatively retain sulfur during fusion, to produce a homogeneous glass disc that is suitable for presentation to an x-ray spectrometer with no additional sample preparation, and to help protect platinumware from attack by sulfide minerals.

Highly oxidizing conditions are necessary both to retain sulfur and to protect platinumware from sulfide attack. Previous researchers have shown that sulfur may be lost under reducing conditions. All of the fusions in this study were performed in an oxidizing environment, using a muffle furnace.
The Use of EDXRF for Liquids in a Uranium-Vanadium Solvent Extraction Process
Authors: Smith Rocky A.
Published: March 2019

Elements of importance in a uranium-vanadium solvent extraction process can be monitored using EDXRF. Fifteen independent circuits were monitored for six different elements on a hourly basis. The precision of the analysis varies from element to element and from circuit to circuit, but all precision was within acceptable limits set for mill control by more conventional means of analysis. The elements of primary interest were uranium and vanadium.
A Combined Dilution and Line-Overlap Coefficient Solution for the Determination of Rare Earths in Monazite Concentrates
Authors: Smith T. K.
Published: March 2019

The rare earth elements (REE) together give guite complex X-ray emission spectra with a considerable number of overlaps at analytical energies by lines of other REE with lower atomic numbers. Where the concentration of REE is high, as in lanthanide minerals, this Interference is more difficult to rectify. Smith and Gold resolved a similar problem with lower atomic number elements in energy dispersive microprobe analysis by establishing a series of overlap coefficients. They asserted that accurate corrections were necessary because of the relatively poor overall resolution of the instrument and that these should not be limited to the major coincidences. Some of the smaller values had probably been ignored because they were considered statistically Insignificant. The mathematical matrix of Smith and Gold covered 22 elements from fluorine to barium, with intensity coefficients (other than intraelement) quoted from 0.01% to 282.1% and with ZAF corrections necessary in cases of K to L conversion. The overlap coefficients were also adjusted for matrix effects.
A Versatile Minicomputer X-Ray Search/Match System
Authors: Parrish W. , Ayers G. L. , Huang T. C.
Published: March 2019

The operation of a new polycrystalline phase identification method using the IBM Series/1 minicomputer is described. Data of the unknown can be entered by automatic transfer of previous runs, stored data sets and manually. Full screen menu selections are provided to facilitate operations and correct entries. Typical S/M time for a multi-phase inorganic mixture containing 43 reflections using a 0.3° window averaged 11 sec per 100 standards and with simple chemical prescreening less than 4 sec including program initialization and calculations of comprehensive figures of merit. Interactive options provide graphics terminal comparison of the unknown pattern with selected standards which appear as diffractometer patterns, subtraction of identified standards from the unknown and others. Utility programs permit storing data sets for later analysis, user created files and a program to display any file standard as a diffractometer pattern.
X-Ray Diffraction Phase Analysis Using Microcomputers
Authors: Hare T. M. , Russ J. C. , Lanzo M. J.
Published: March 2019

X-ray diffraction to determine the phases present in complex specimens generally proceeds by acquiring a pattern of D-spacings and intensities from the sample, which is then compared to patterns from a series of known or standard phases. The process of searching through large data bases to identify matches is too time consuming for manual methods, and so computerised search/match programs have come into use. The magnitude of the general problem, in which perhaps 40,000 known patterns (corresponding to the present size of the JCPDS powder diffraction file) are involved, places it in the realm of large nainframe computers, which are often accessible on a time-share basis by many laboratories or researchers using XRD. On the other hand, in many practical applications, the search need only be carried out over a limited range of compounds which are expected or may possibly be present based on the known history of the material, or on its independently determined composition. In this case, the data base becomes much smaller, and can be accommodated In micro- and minicomputers. The system we report here utilizes a 64K-byte 8 -bit microcomputer (Apple 11+) with dual floppy disk drives. One 5-1/4 inch disk can hold the pattern information for fifty compounds, and can be searched for possible matches in a few minutes. The same computer can control the scanning diffractometer to acquire the pattern data, and can act as an intelligent terminal to larger time-share machines when it is necessary to access the large data bases.
Application of the Modified Snyder's Program for the Data Processing of an Automated X-Ray Powder Diffractometer
Authors: Platbrood G. , Quitin J. M. , Barten H.
Published: March 2019

X-ray diffraction analysis is an excellent analytical tool. But if a certain quality of the results is needed or if solutions of analytical problems are to be obtained in a short time period, the X-ray diffractometer must be automated and the spectra reduced with dedicated algorithms.

In LABORELEC, three programs are principally used to solve the problems encountered in the X-ray diffraction analysis: a modified program given by R. L. Snyder; the search/match G. G. Johnson program (last version); and the POWD5 program.
Complete Quantitative Analysis Using Both X-Ray Fluorescence and X-Ray Diffraction
Authors: Garbauskas M. F. , Goehner R. P.
Published: March 2019

The advantages of using elemental information to assist in the interpretation of x-ray diffraction (XRD) data are well known and many of the modern search/match algorithms utilize chemical information to make the procedure faster and more reliable (1). Elemental data can also be used to facilitate the quantitation of phases ideittified by x-ray diffraction, in some cases eliminating the need for performing the quantitation based upon the diffraction pattern. There are certain advantages to this approach. The first is that certain difficulties encountered in XRD quantitation such as line overlap, particle statistics, preferred orientation, microabsorption, extinction, and lack of pure Standards are alleviated. The second is that the elemental analysis is, as a rule, easier and more sensitive than the diffraction technique. It therefore should be possible to increase the ease and the accuracy of quantitative phase analysis by utilizing the chemical data available. Since most materials submitted for XRD analysis are in form acceptable for x-ray fluorescence (XRF) analysis, this is the quantitative elemental technique of choice. However, it should be noted that other elemental analysis techniques can be used instead of XRF to furnish the chemical analysis.