bluuebunny/crossref_metadata_2025_split huggingface dataset:
Applications of X-ray Diffraction Crystallite Size/Strain Analysis to Seismosaurus Dinosaur Bone
Authors: Chipera Steve J. , Bish David L. 
Published: March 2019

AbstractRecently, the remains of a giant Cretaceous Sauropod (~150 My old) were discovered in the Morrison Formation west of Albuquerque, New Mexico. This dinosaur, tentatively named Seismosaurus, was found in an exceptional state of preservation. Although it has been known since the 180Q's that fossilized bone is often composed of the mineral apatite, very few studies have been conducted to characterize farther the fossilized material. In an effort to gain insight into the state of preservation and Hie processes occurring in the bone since deposition, apatite in bone from Seismosaurus was compared with that from a contemporary elk from the Jemez Mountains, New Mexico, and with well-crystallized mineral apatite using X-ray powder diffraction and profile analysis techniques. Crystallite size/strain analyses were conducted using the Scherrer equation, the Warren-Averbaca and single-line methods, and the Rietveld method using the program GSAS. Heating the contemporary elk bone produced a decrease in the full-width-at-half-maximum (FWHM) of the reflections in the diffraction pattern. This decrease in FWHM is due to a decrease in microstrain along with a minor increase in crystallite size. Results from crystallite size/strain analysis show that both Seismosaurus and contemporary elk bone crystallites are elongate parallel to the c-axis. However, Seismosaurus bone crystallites are larger (-20-65 nm) with less strain than the contemporary elk bone crystallites (-8-20 nm), suggesting that if elk bone is an appropriate analog, then Seismosaurus bone must have undergone recrystallization.
The Effect of Satellite Lines from the X-ray Source on X-ray Diffraction Peaks
Authors: Briden Frank E. , Natschke David F. 
Published: March 2019

We have been using crystallite size and strain data obtained from x-ray diffraction (XRD) peak profile analysis to predict the reactivity of solid calcium hydroxide sorbent with acid gases in combustion streams. The development of the method for relating reactivity to crystallite size and strain parameters obtained by the Warren-Averbach technique has been reported by Briden and Natschke and Briden.The software used for the calculations requires that the XRD peak profile be corrected with a distribution function before application in the Warren-Averbach analysis. The reason for this according to the software developer, Gerhard Zorn, of the Siemens Munich Laboratory, is that he has shown that contributions to the profile from alien peaks and random noise can have serious effects on the Warren-Averbach analysis. The fitting of (he experimental XRD peak with a distribution function provides an effective means for filtering out both contributions.
X-Ray Fluorescence Minor- and Trace-Element Analyses Silicate Rocks in the Presence of Large Interelement Effects
Authors: King B. S. , Espos L. F. , Fabbi B. P. 
Published: March 2019

An X-ray fluorescence (XRF) method has been devised for the rapid quantitative determination of 16 minor and trace elements in geological materials. This method, a modification of a direct dilution method (1, 2, 3), uses a sample-to-binder ratio of 85:15 for sample preparation. Pellets prepared by this method are durable and do not deteriorate rapidly when exposed to high X-ray irradiation. Interferences and matrix effects are successfully corrected in actual analyses by employment of multiple linear regression equations.Accuracy and precision have been improved over the method previously used in this laboratory. Detection limits have been lowered for Zn, Rb, Y and Zn approximately by the factor of 2. When interelement corrections are made, the XRF values are found to be in good agreement with the preferred chemical values for the 19 international silicate-rock standards.
The Effect of Various Pattern Aberrations on Figures of Merit Used With Whole Pattern Recognition Techniques
Authors: Smith D. K. , Hoyle S. Q. , Johnson G. G. 
Published: March 2019

AbstractThe affect of several aberrations on the figures of merit, FOM, used in the identification analysis of diffraction patterns has been examined by generating simulated diffraction traces with mathematically induced errors. Patterns of mixtures with random 20 shifts, intensity variations, and profile broadening were generated for analysis by MATCHDB, and the behavior of three FOMs during the search step was followed. The results have shown that the angle errors are the most serious in degrading the potential for identification of the phases in the mixtures. Intensity errors cause some degradation on the results. Broadening has little affect when using whole-pattern matching methods.
The Use of a Conventional Powder Diffractometer for Thin-Film Thickness Determination From Reflectivity DATA
Authors: Huang T. C. , Gilles R. , Will G. 
Published: March 2019

AbstractPrecise thin-film thicknesses have been obtained from X-ray specular and off-specular reflectivity data collected with a conventional powder diffractometer. An analysis of the specular reflectivity curve for a 565.9-Å thick pt film showed the results agreed with those determined previously from high-resolution reflectometer data to within 6.6 Å or 1.2%. An analysis of the off-specular reflectivity curves which have well-defined interference fringes showed that the results were insensitive to the surface alignment. Values of Pt thickness for the off-specular reflectivity curves agreed with that of the specular reflectivity curve to within 6.2 Å or 1.1%. The insensitivity in film-surface misalignment makes conventional powder diffractometer attractive for film-thickness determination and opens this techniques to many laboratories.
Complicated Average Stress-Fields and Attempts at Their Evaluation With X-Ray Diffraction Methods
Authors: Ruppersberg H. 
Published: March 2019

AbstractConventional X-ray stress analysis is based on the so called "linear sin2ψ" law and yields average two axial stresses in the irradiated surface layer of polycrystalline specimens. Three examples are given in this paper where either strong deviations from the linear law are observed due to stress gradients or where the linear law yields wrong results because of three axial stresses. Special experimental techniques are described and formalisms are given for the evaluation of the corresponding stress fields which are in the described cases more complicated than usual.
On-Line Analysis Of Molten Metals Using a Wavelength Dispersive X-Ray Spectrometer
Authors: Creasy Larry E. 
Published: March 2019

AbstractThe electron beam furnace is a nearly ideal tool to conduct on-line analysis of molten metal. In the process of melting the metal with a high intensity electron beam, x-rays are created. A wave-length dispersive x-ray spectrometer, specially designed for this environment, has been used to analyze the composition of the molten metal. This significantly reduces the time required to determine the concentration of critical elements in the melting process.
Data Sets for Evaluation of Powder Diffraction Search/Match Algorithms
Authors: Pfoertsch Diane E. , Hamill Gregory P. , De Camp Wilson H. 
Published: March 2019

Among powder diffractionists, there is a concern about establishing criteria for testing existing and new computer methods for searching the Powder Diffraction File (PDF) data base. A large number of papers on this subject have been presented at recent Denver Conferences and at other meetings, such as the American Crystallographic Association.The PDF now exceeds 42,000 patterns, with an average of about thirty lines per pattern. Thus, it contains approximately 2.5 million numerical values. At its current rate of growth, the PDF will double in less than twenty years.
A Useful Guide for X-Ray Stress Evaluation (XSE)
Authors: Hauk Viktor M. , Macherauch Eckard 
Published: March 2019

AbstractThis paper summarizes experiences available for the measurement of lattice strains in different materials with different wavelengths to evaluate stresses by means of X-rays. The recommendations given are based on previous statements. Some principles of fundamentals of X-ray physics for the recording of interference lines with Ω and ψ-diffractometers are dealt with. Methods applicable for the determination of the peak position of the interference lines, the assessment of linear and non-linear lattice strain distributions, and tine calculation of stresses are outlined. For iron, aluminium, copper, nickel and titanium the constants for practical X-ray stress evaluation (XSE) and the parameters of measurement are tabled.
Small Area X-Ray Diffraction Techniques; Applications of the Micro-Diffractometer to Phase Identification and Strain Determination
Authors: Goldsmith C.C. , Walker G.A. 
Published: March 2019

AbstractThe trend towards smaller devices and packages in the semiconductor industry makes it increasingly important and increasingly difficult to obtain useful X-ray diffraction information from the small areas employed. This study covers applications of a Rigaku micro-diffractometer to measure strain and obtain phase information from areas less than 100μm in diameter. Examples of residual stress mappings between electrical vias only 100μm apart and phase determination on a single electrical via 120μm diameter will be shown.
X-Ray Measurement of Triaxial Residual Stress in Ceramic Composites and Coating
Authors: Tanaka Keisuke 
Published: March 2019

AbstractThe X-ray diffraction method was used to measure the triaxial state of residual stresses in each phase in the following four kinds of composites; ZrO2/Al2O3 composite, WC-Co alloy, SiC/Al-alloy composite, and TiC/SiC coating. The residual macrostress and microstress were determined from the phase stresses by using the rule of mixture. The effects of heat treatment and surface finishing on the residual stress were studied. The measured value of the thermal residual stress was compared with the theoretical prediction based on the mismatch of the coefficient of thermal expansion.
Highly Sensitive X-Ray Stress Measurement in Small Areas
Authors: Fujii Nobuyuki , Kozaki Shigeru 
Published: March 2019

AbstractThe authors tried a new measuring method for stresses in small areas of ceramics. This method is characterized by the following.1)Applicable to small areas.2)High sensitivity.3)Stress calculations by measuring the average Debye ring radius in view of spotty diffraction rings.4)The use of an imaging processor for (3).5)The use of an imaging plate (IP) for reducing the exposure time.We worked out a computer simulation about errors of the values measured by our method. The result showed a good approximation. With a test piece applied with a certain load, the difference between stresses measured by our method and those by a strain gauge was about 12 percent. We applied this method to the measurement of residual stresses which took place near the silicon nitride (Si3N4)/304 stainless steel brazing point interface. In the case of using an X-ray beam of 100 μm diameter, the exposure time was 90min with a high sensitive X-ray film and 3min with the imaging plate. In the case of an X-ray beam of 40 μm diameter, it was 120 to 190 min with the imaging plate.
Measuring Residual and Applied Stress using X-Ray Diffraction on Materials with Preferred Orientation and Large Grain Size
Authors: Pineault James , Brauss Michael 
Published: March 2019

AbstractOne of the most difficult tasks in applied and residual stress measurement of polycrystalline materials using x-ray diffraction is dealing with preferred orientation and large grain size.A common solution to large grain size problems has been to choose a larger aperture, but in certain cases this is undesirable and/or impossible. When preferred orientation has been identified as the problem, the common approach has been to choose another diffraction plane or oscillate the x-ray diffraction head during data collection. Remedies such as these can distort the peak breadth and are often not sufficient to totally negate the grain size and preferred orientation effects.A technique described as the “step scan with virtual window” has been developed jointly at MTL (formerly Canmet) and Proto Mfg. Ltd. to deal specifically with the aforementioned effects of grain size and preferred orientation.This paper highlights some of the problems that arise in stress analysis of materials exhibiting preferred orientation and large grain size. Subsequently a comparison of the results obtained using standard diffraction technique, oscillation and the “step scan with virtual window” is made.
X-ray Topography of Surface Layers and Epitaxial Films
Authors: Bowen D. Keith 
Published: March 2019

AbstractThe techniques of X-ray topography are reviewed, with special reference to their application to the study of surface layers and thin films. The methods of section topography, white radiation topography and double and triple crystal topography are shown to be the most appropriate, with grazing or glancing incidence methods assuming special importance. Applications to the questions of epilayer mismatch and dislocation content, process-induced defects and surface damage are discussed.
Residual Stresses and Differential Deformation of Electroplated Structures
Authors: Sheikh G. , Noyan I. C. 
Published: March 2019

AbstractWe report the results of a recent study where nickel substrates electroplated with chromium were loaded in-situ on an x-ray diffractometer. This technique allows determination of lattice spacings in the vicinity of the interface for both the film and the substrate as a function of the applied load. We used such lattice parameter data, SEM observations of the surface and x-ray peak breadth data to study the partitioning of deformation between the film and the substrate. The data indicates progressive loss of adhesion between the film and the substrate with increasing deformation. We observe significant effect of electroplating residual stresses on the mechanical behavior of the system. The loss of adhesion between the film and the substrate coupled with the initial residual stress profile causes an apparent 'negative Poisson's ratio' for the film during initial stages of the loading. This effect disappears with cyclic loading and unloading.
Derivation of d-Values from Digitized X-ray and Synchrotron Diffraction Data
Authors: Huang T. C. , Parrish W. , Masciocchi N. , Wang P. W. 
Published: March 2019

AbstractA precise and practical method for the determination of d-values and lattice parameters from digital diffraction data is described. Systematic errors are corrected mathematically during a d-spacing / lattice-parameter least-Squares refincment process making it unnecessary to use internal standards. X-ray and synchrotron diffraction data of an ICDD alumina plate obtained with a wide variety of experimental conditions and analysis parameters were used to study the precision in the derivation of d-values and the accuracy in the determination of lattice parameters. Results showed that the precision in determining d-values was high with |Δd/d|avg ranging from 2x105 to 4x10-5. Using the results obtained from the high precision XRD analysis as a reference standard, the accuracy in the lattice parameter determinations from the synchrotron diffraction data reached the l-2x10-6] range. Lattice parameters, with an accuracy in the high 10-5 range, were also obtained using parameters commonly used in a routine XRD analysis such as a wide RS (0.11°) for high intensity, peaks only in the front reflection region, no Kα2 stripping, and a Single 2θo parameter for systematic error corrections.
Determination of Rolling Contact Stress Distribution by X-ray Diffraction
Authors: Milan David L. 
Published: March 2019

AbstractAn investigation was conducted of the potential for detection of the contact stress distribution in tapered roller bearing components made of carburized steel. Various raceway stress distributions were created by control of the profile and alignment of the rolling surfaces. Determination of residual stress in the rolling direction and peak breadth were made using a multiple tilt sin2ψ technique. The measurements were made at the surface and at depths below the surface. It was found that the distribution of residual stress and peak breadth perpendicular to the rolling direction in the layers below the surface of the inner race correlated highly with the imposed contact stress distribution. The correlation was less in the case of the outer race. The residual stress distribution measured on the surface of the inner race was observed to be inversely proportional to the contact stress distribution.
Diffraction Plane Dependence of X-ray Elastic Constants of Alumina
Authors: Kurita Masanori , Ihara Ikuo , Saito Akira 
Published: March 2019

AbstractThe 95% confidence linits of the x-ray elastic and stress constants of α-alumina were detemined from seven kinds of diffraction planes by the Gaussian curve method in order to investigate the diffraction plane dependence of the eonstants. No difference in the elastic constants larger than their 95% confidence intervals was observed for most diffraction planes. Also, the measured elastic constants for most planes were closer to the values calculated from the Voigt model than those from the Reuss model. Since the diffraction line of the (410) plane measured with cobalt Kα radiation by using an automated x-ray stress analyzer locates at the highest diffraction angle of 168.4, the use of this plane will allow the most accurate stress measurement. Also, the measured x-ray elastic constants for the (410) plane almost agreed with both values calculated from the Voigt and Reuss models. Therefore, the (410) plane is the most appropriate plane for x-ray stress measurement of alumina.
Numerical Resolution Enhancement of X-ray Diffraction Patterns
Authors: Ohno Katsumi , Harada Hiroshi , Yamagata Toshihiro , Yamazaki Michio 
Published: March 2019

AbstractA numerical resolution-enhancement method was developed for x-ray diffraction data measured with a conventional x-ray diffractometer. This method removes the instrumental broadening due to x-ray optics, including the spectral distribution of the x-ray source such as the CuKα doublet. The advantages of this method are to separate the cluster of peaks in x-ray powder patterns into individual peaks without previous knowledge of the number of peaks, and to remove CuKα2 reflection peaks automatically.The instrumental window function, which was approximated by a modified pseudo-Voigt function, was calculated from the measured diffraction pattern of NBS Standard Reference Materials (640B) by a non-linear least squares method. The simple diffraction patterns, including no CuKα2 peaks, were obtained from the diffraction patterns measured with the conventional x-ray diffractometer by using the window function mentioned above.The application of the method of determination of the lattice misfit between γ and γ phases in Ni-base superalloys was also described.
Standard Database Format for the Dissemination and Storage of Diffraction Data - Task Group Progress Report on JCAMP-DX
Authors: Hamill G.P. , Jenkins R. , Schreiner W.N. 
Published: March 2019

AbstractIn planning for PDF-3, the International Centre for Diffraction Data's full pattern database of raw diffraction data, it is evident that a standard format for storage and exchange of diffraction data is necessary. An evaluation of the JCAMP-DX protocol by a task group* of the International Centre for Diffraction Data has resulted in a set of format cooes specific to X-ray diffraction. The proposed structure of the data is divided into four parts: the minimal component set required by the JCAMP-DX definition (name, data, owner, sample identification, data type, etc.), a minimum item set required to define the X-ray diffraction data, an open selection of requested but not required information on the sample, its preparation and the instrument, and finally the data itself in one of several specified formats. All information stored in JCAMP-DX format is in ASCII characters. Therefore, these data are printable, easily read by the user and compatible with almost any computer or media storage device. Codes defining the information are primarily in shortened, but readable, English. The task group is completing the work on this project and will be presenting its proposals to JCAMP.
Crystal Chemistry and Phase Equilibria of the BaO-R2O3-CuO Systems
Authors: Wong-Ng Winnie , Paretzkin Boris , Fuller Edwin R. 
Published: March 2019

AbstractTwo important factors, the progressively decreasing size of the lanthanides, which is known as the lanthanide contraction, as well as the stability of different oxidation states of these elements influence the prediction of compound formation in the Ba-R-Cu-O systems. A systematic investigation of these lanthanide systems and comparison with the Y system has revealed a correlation of the effect of the above factors, in particular the size factor, on the trend of phase formation, solid solution formation and phase compatibility diagrams of the Ba-R-Cu-O systems. For example, it has been found that the smaller the size of R3+ or the greater the mismatch betwaen Ba2+ and R3+ in the solid solution series Ba2-ZR1+lCu3O6+x, the smaller the extent of solid solution formation. This differing extent of solid solution formation influences the ternary phase relationships.
An Artificial Intelligence System for XRF Data on a Personal Computer
Authors: Wittig Erland P. , Rechsteiner Carl E. 
Published: March 2019

SummaryAutomation of X-ray fluorescence equipment has proliferated during the last 10 years. However, the focus has been on data collection and data massage. Data presentation has been limited to a few rudimentary formats. These formats ‘ generally involve printing the results in some arbitrary fashion, followed by manual transfer to the client.This paper describes a system (using rudimentary artificial intelligence techniques) that automates data presentation. It handles data from 14 different methods; evaluates the data against the requirements of the method (i.e. mass balance, detection and reporting limits, and matrix interferences). Further, a data report is generated in a consistent format, including the reporting of significant figures. Additionally, an exception report is printed when the measured results are outside the applicable range of the method or violate quality assurance constraints. In such cases, alternative methods are recommended in the exception report.