bluuebunny/crossref_metadata_2025 huggingface dataset:
Computer Identification Techniques for Crystalline Compounds Using the JCPDS Powder Diffraction File as a Data Reference
Authors: Van Trump George , Hauff Phoebe L.
Published: March 2019

The mineralogy laboratory of the U.S. Geological Survey in Denver has developed a series of time-sharing oriented computer programs which aid in the identification of crystalline compounds from chemical and X-ray diffraction data. These programs operate on a data base compiled primarily from the Powder Diffraction File of the Joint Committee on Powder Diffraction Standards (JCPDS). Diagrammatic X-ray diffraction patterns and various search tables are products of these programs. Additional programs can retrieve information from the data base by chemical formula components or Powder Diffraction File number, and can search and match reflections of an unknown against reference patterns.
A Round Robin Test to Evaluate Computer Search/Match Methods for Qualitative Powder Diffractometry.
Authors: Jenkins Ron
Published: March 2019

A preliminary round robin test to evaluate available computer search/match has been carried out and comparisons made with handsearching techniques. Participants in the teat were all experienced diffractionists and a variety of data collection instrumentation was employed. Hand-searching and computer searching were found to be equally efficient, about 70-80%, for the mineral and inorganic samples provided that the quality of the “d” values was good (1 in 1000). Although the computer methods were much quicker, they were found to be much more sensitive to the quality of the “d” values. Where elemental data was used to assist in computer searching, much poorer “d“ values (3 in 1000) were acceptable. Hand-searching was found to be vastly superior to computer searching for the organic specimen.
The Effect of the Kα Doublet Diffracted Peak Position on the Precision of the Lattice Constant
Authors: Gazzara C. P.
Published: March 2019

The effect of the position of the X-ray unresolved Kα1 - Kα2 line doublets, diffracted from powder specimens, on the precision of the calculated lattice constant has been determined using a least-squares analysis. An analytical procedure to synthesize CuKα doublet X-ray diffraction peaks with X-ray characteristic lines (half widths ranging from 0.1° to 0.4° 26) has been applied in correcting the weighted wavelength of the doublet peak position. A series of correction curves was established from which the true 26 peak position of the weighted Kα wavelength could be determined from the measured 29 peak position.
Crystal Subgrain Misortentations Via X-ray Diffraction Microscopy
Authors: Armstrong R. W. , Wu C. Cm.
Published: March 2019

The “misorientation. contrast” which occurs at boundaries marking the relative displacement of adjacent subgrain reflections in x-ray diffraction images is shown by a stereographic projection method of analysis to be useful for deciphering x-ray images obtained by the Berg-Barrett and Lang techniques. Experimental results are given for subgrain structures observed in Zn and A1203 crystals.
Stress Measurements on Cold-Worked Fastener Holes
Authors: Dietrich G. , Potter J. M.
Published: March 2019

Magnitude and distribution of residual stresses around cold-worked holes in 1045 steel were measured with the Fastress automatic stress X-ray analyzer. Permanent interferences between 0.8% and 6.2% at a hole with 0.5 in. diameter produced compressive hoop and radial stresses up to -60 ksi and -40 ksi respectively. The size of the zone with compressive stress is significantly wider than existing analysis predicts.
Diffraction Technique for Stress Measurement in Polymeric Materials
Authors: Barrett Charles S.
Published: March 2019

Stresses in polymeric materials can be measured by diffracting X-rays from embedded crystallites that yield suitable powder diffraction lines. An appropriate technique for this has been, reported by C. S. Barrett and Paul Predecki elsewhere and is reviewed here with additional details. It is based on a diffractometer modified so as to operate at very high 26 angles, with specimens prepared in various ways. Results show that adequate precision is reached by scanning Ka doublet in a few minutes and simply noting any displacement of peaks compared with peaks from an unstressed specimen; higher precision can be reached with slower scans or more detailed analysis of the peaks. Tests with embedded metallic particles were successful when the particles were (A) distributed throughout a moulded polymethyl methacrylate (Lucite) sheet of the order of a millimeter thick, alone or sandwiched between layers of particle-free material, or (B) embedded in polyester resin applied to a surface of Plexiglas bars, or (C) embedded in graphite-fiber epoxy composites in a layer at a chosen position within a specimen.
Polymer Films as Calibration Standards for X-ray Fluorescence Analysis
Authors: Dzubay T. G. , Lamothe P. J. , Yasuda H.
Published: March 2019

A new type of calibration standard has been developed for X-ray fluorescence analysis of thin samples. Each standard consists of a polymer film containing a single calibration element. The film is cast from a homogeneous solution containing known amounts of an organometallic compound and a polymer. Polymers of cellulose acetate-propionate and polystyrene are used because of their low moisture affinity. The films have a low (2-4 mg/cm2) mass per unit area for minimal X-ray attenuation. Standards of V, Co, Hi, and Pb have been successfully made. Typical concentrations of 20 μg/cm2 yield excellent spectra with a low background. The method shows promise for making standards of additional elements.
Advances in the Preconcentration of Dissolved Ions in Water Samples
Authors: Leyden D. E.
Published: March 2019

X-ray fluorescence is well established as an analytical method for the determination of multi-element systems. It is a technique which provides high accuracy and precision. However, it has serious limitations in the lower limit of detection for elemental analysis in environmental samples. In order to overcome this limitation some method of preconcentration or enrichment of the trace elements in water samples must be provided. In recent years many techniques have been developed for this purpose. Some of these techniques involve simple chemical or physical manipulations of the sample. In all cases, the technique should be rapid, simple, and not contaminate the sample. Because it is more convenient to use solid samples for X-ray fluorescence analysis, the ideal method of preconcentration results in a solid sample.
Preconcentration of Uranium in Natural Waters for X-ray Fluorescence Analysis
Authors: Hathaway L. R. , James G. W.
Published: March 2019

Use of Chelex-100 impregnated filter membranes for preconcentration of uranium in ground-water samples for XRF analysis leads to lower processing time, sample size, and detection limit than achieved in a batch extraction process. Data is presented, for potential effects of iron and organic matter in natural waters upon the recovery of uranium when using Chelex-100.
Use of X-ray Scattering in Absorption Corrections for X-ray Fluorescence Analysis of Aerosol Loaded Filters
Authors: Nielson K. K. , Garcia S. R.
Published: March 2019

Two methods are described for computing multielement x-ray absorption corrections for aerosol samples collected in IPC-1478 and Whatman 4l filters. The first relies on scatter peak intensities and scattering cross sections to estimate the mass of light elements (Z < l4) in the sample. This mass is used -with the measured heavy element (Z ≥l4) masses to iteratively compute sample absorption corrections. The second method utilizes a linear function of ln(μ) vs. ln(E) determined from the scatter peak ratios and estimates sample mass from the scatter peak intensities. Both methods assume a homogeneous depth distribution of aerosol in a fraction of the front of the filters, and the assumption is evaluated with respect to an exponential aerosol depth distribution. Penetration depths for various real, synthetic and liquid aerosols were measured.
A Noval X-ray powder Diffractometer Detector System
Authors: Byram Susan K. , Han Bui , Rothbart G. B. , Samdahl Roger N. , Sparks Robert A.
Published: March 2019

A new proportional counter x-ray detector with application for powder diffractometry has been developed. The new detector collects virtually the entire diffraction spectrum simultaneously with good efficiency and angular resolution. Thus, the powder spectrum of a small sample can be obtained much faster than with film or a conventional powder diffractometer. The detector read-out is digital and is interfaced to a dedicated minicomputer. A description of the detector system is discussed and preliminary results are presented.
Effects of Diffractometer Alignment and Aberrations on Peak Positions and Intensities
Authors: Jenkins Ron
Published: March 2019

The two basic parameters traditionally employed in qualitative phase identification using the powder diffractometer are the diffracted peak maximum intensity and the interplanar spacing “d”. Moat routine powder diffractometry carried out today is performed with the parafocussing geometry, and this arrangement gives a diffraction pattern in terms of diffraction angle (2-theta) vs. intensity. During the course of obtaining a set of experimental 20 and intensity values from a specimen to be analysed and in the subsequent conversion of these data to a d/I list for qualitative phase identification, errors will of course accrue. Most qualitative search methods in use today give high credence to the d-value, since this is by far the most accurately known of the two search parameters, and d-values of a few tenths of a percent are reasonably easily obtained with a well aligned and properly calibrated diffractometer. Intensities, on the other hand, can be subject to errors of the order of tens of percent, and problems arise in qualitative analysis where the need arises to subtract an identified phase from a multi-phase pattern to allow identification of further phases.
Accuracy and Precision of Intensities in X-Ray Polycrystalline Diffraction
Authors: Parrish W. , Huang T. C.
Published: March 2019

The integrated and peak intensities of a series of silicon powder samples of various crystallite sizes were measured with a computer automated diffractometer and a profile fitting method (PFM). The accuracy of the PFM was better than 0.003% in computing the integrated intensities. The PFM gave more precise values than would be expected from counting statistics of the peak intensity. The average difference between each measurement and the average intensity was 0.5% with little dependence oo the absolute intensity. Crystallite sizes have a large effect and it is essential to rotate the specimen around the diffraction vector. The best results were obtained with <10 μm particles. Larger sizes decrease the absolute intensities and change the relative intensities. Structure refinement using the POWLS (powder least squares refinement) program showed the presence of (111) preferred orientation even in the <10 μm specimens. R(Bragg) decreased from 4.3% to 0.7% by including the preferred orientation correction in the refinement.
New Standard Reference Materials for X-Ray Powder Diffraction
Authors: Hubbard Camden R.
Published: March 2019

Standard Reference Materials (SRMs) from the National Bureau of Standards are samples or artifacts certified for one or more particular parameters. The NBS has produced SRHs since 1905 to aid commerce, to improve measurement technology and to assist in the enforcement of regulations. Today nearly 900 different SRHs are available to serve major segments of industry such as ferrous metals, nonferrous metals, mining, glass, primary chemicals, computer, nuclear power and electronics. In addition to the industrial customers, major SRM users include both federal and state governments, universities and nonprofit research organizations.
An Evaluation of Some Profile Models and the Optimization Procedures Used in Profile Fitting
Authors: Howard Scott A. , Snyder Robert L.
Published: March 2019

This paper examines some of the concerns regarding the development of an algorithm for the refinement of X-ray diffraction profiles. The object of the algorithm is to provide a time efficient method of refinement through the choice of a suitable profile function and optimization technique.

Seven profile models were tested using a least-squares error criterion for refinement. Profile parameters were refined using non-linear Gauss-Newton, Marquardt and Simplex algorithms. The profiles were refined on a pattern digitally collected from an NBS 640A silicon sample.

The results of this study indicate the repetitive function evaluations are not necessarily the time consuming step in the profile fitting process. As the number of parameters needed to evaluate the profile and the number of points in the profile increases, the time required to perform the mathematics in the Gauss-Newton and Marquardt algorithms increases. Although the Simplex was most memory and time efficient, our Gauss-Newton optimization algorithm provided a more consistent set of refined values which were not as dependent on the initial estimates of the parameters.

The most favorable results were obtained by using the split Pearson VII profile with the alpha 2 reflection fixed in position and intensity with respect to the alpha 1 reflsction. This method generated the lowest residual error and was found to avoid some problems resulting from the alpha 1, alpha 2 line overlap.
Computer Search/Match of Standards Containing a Small Number of Reflections
Authors: Huang T. C. , Parrish W. , Post B.
Published: March 2019

A simplified and effective computer Search/Match method is described in which no more than 12 largest d-value reflections regardless of intensities are used for the Powder Diffraction File standards. A quantitative procedure utilizing the figure-of-merit in the IBM Search/Match method was employed to show the applicability to inorganic, mineral and organic mixtures. The analyses gave the same results as the complete File but the standard databases and analysis time are reduced by about a factor of two. Search/Match without using intensities also gave the same results; this may be useful when instrument geometry and/or preferred orientation cause large errors in the relative intensities. The error limits in measuring the d-spacings were found to vary from ±0.1° to 0.5° (26) depending on the degree of overlaps.
A Comparison of Methods for Reducing Preferred Orientation
Authors: Calvert L. D. , Sirianni A. F. , Gainsford G. J. , Hubbard C. R.
Published: March 2019

Preferred orientations in powder diffraction specimens can cause large errors in measured intensities. An extreme case is shown in Figure 1, Smith and Barrett (1979) reviewed the various methods which have been proposed for reducing this effect. Subsequently, two methods which are used commercially for aggregating finely divided solids have been proposed for preparing powder diffraction specimens (Smith, Snyder, and Brownell, 1979; Calvert and Sirianni, 1980). In one of these, spray drying, a finely divided solid is suspended in a liquid together with small quantities of a deflocculent and a binder. This mixture is pulled by venturi action through a nozzle into a heated chamber. The spherically shaped aggregates dry before falling to a collection surface. The apparatus is fairly large (3 X 3 X 4 ft. at NBS), and operating parameters must be carefully chosen.
An X-Ray Diffraction Study of CaNi5 Hydrides Using In Situ Hydriding and Profile Fitting Methods
Authors: Gainsford G.J. , Calvert L.D. , Murray J.J. , Taylor J.B.
Published: March 2019

The CaNi5 system is unique among the AB5-H systems in that it exhibits three distinct hydrides (β, γ, δ) at pressures below 65 atm. (Sandrock et. al., 1982), The present diffraction study was designed to characterise these phases, only one of which has been previously studied. Nowotny (1942) gave lattice parameters for a number of AB5 (Haucke) phases including CaNi5. Takéuchi et al. (1966) gave parameters for CaNi5. Buschow (1974) reported on the entire Ca-Ni system. Oesterreicher et al. (1980) gave data on CaNi5 and CaNi5H5.5. Ensslen et al. (1981) indexed CaNi5H5.5 (γ-phase) as orthorhombic. Measurements made at NRC on one of the samples studied by Sandrock et. al (1982) and on three samples prepared at NRC are given in Table 1 together with the data from the literature. It is clear that there is a significant sample effect on the observed lattice parameters. It is well known that many AB5 compounds have a range of composition. To avoid variations due to sample effects it was decided to characterise the hydride phases on a single specimen.
The Use of X-Ray Diffraction and Infrared Spectroscopy to Characterize Hazardous Wastes
Authors: Kendall Douglas S.
Published: March 2019

The National Enforcement. Investigations Center of the EPA provides support services for the enforcement activities of the Agency. Recently, we have analyzed hazardous wastes as part of efforts to enforce the Resource Conservation and Recovery Act. Inorganic analysis often consists of elemental determinations. However, sometimes it is necessary to identify specific compounds. Some wastes are classified as hazardous by their origin, for instance, the wastes from the manufacture of several chromium pigments. On occasion, it is necessary to trace wastes to their source. In cleaning dumps and treating wastes, knowledge of the compounds present is useful.
An Automated X-Ray Diffractometer for Detection and Identification of Minor Phases
Authors: Russ John C. , Hare Thomas M.
Published: March 2019

In the preceding volume in this series, we described a stepping motor automation package for XRD data acquisition, based on the Apple microcomputer with an interface card that produces the stepping motor pulses and counts X-ray pulses from the normal X-ray detector and amplifier. We are presently using the system to automate a General Electric XRD-5 diffractometer mechanism, by replacing the original synchronous motor with the stepping motor, and installing 10:1 reduction gear instead of the chain drive to drive the double worm gears. This gives 2500 steps of the motor per degree two theta. Motor pulses are counted by a small machine language routine which also handles accelerating the mechanism when slewing over long angular ranges.
Measurement of Stress Gradients by X-Ray Diffraction
Authors: Sprauel J.M. , Barral M. , Torbaty S.
Published: March 2019

Among the limitations of the classical methods for measuring stresses by X-ray diffraction, the existence of stress gradients constitutes a particularly delicate problem. On the theoretical plane, this problem has been tackled by Dölle, Hauk and Cohen. These authors showed that whilst the gradients of the shear stresses σ13and σ23+ are relatively easy to bring to the fore, as their presence is reflected in an opening out of the curves for 2θϕ ψ=f (sin2ψ), those of the direct stresses σ11, σ22 an σ33 are very difficult to detect. In the latter case it is demonstrated that even when the gradients attain very high values, the curves of 2θϕ ψ=f (sin2ψ) remain practically linear. This may invite one to apply the classical sin2ψlaw, with the result that the stress values so determined do not correspond with the real mechanical state of the surface of the specimen.
Application of a Position Sensitive Scintillation Detector for Nondestructive Residual Stress Measurements Inside Stainless Steel Piping
Authors: Ruud C.O. , DiMascio P.S. , Melcher D.M.
Published: March 2019

As early as 1974 cracking was observed in the austenitic stainless steel piping systems of several Boiling Water Reactors [1,2]. Failure analysis indicated that the cracks developed through intergranular stress-corrosion cracking and an active interest in residual stress measurement methodologies developed. This paper describes the procedures and demonstration testing employed to provide absolute residual stress measurement, nondestructively, on the inside surface of pipe specimens. A Ruud-Barrett position sensitive detector (PSSD)* was used to build an EPRI pipe stress analyzer which was developed for these residual stress measurements [3,4].
Analytical and Experimental Investigation of Flow and Fracture Mechanisms Induced by Indentation in Single Crystal MgO
Authors: Larchuk T. , Kato T. , Pangborn R. N. , Conway J. C.
Published: March 2019

The flow and fracture behavior of ceramic and other brittle materials under the influence of contact loading is important to both component fabrication and performance. The ease of machining, severity of residual surface damage and rate of wear during subsequent service are controlled to a large degree by the character and extent of the flow zone and its influence on the fracture mode. This Investigation was undertaken to provide experimental verification of the results obtained through elastic/plastic finite element modeling cf the stress distribution and deformations introduced by static contact loading. Experimentally, X-ray double-crystal diffractometry (DCD) was applied to obtain a mapping of the distortions produced beneath a Vickers indenter, and hence to evaluate the effect of material and geometric parameters on the flow and fracture mechanisms.
X-Ray Polarization: Bragg Diffraction and X-Ray Flurorescence
Authors: Zahrt John D.
Published: March 2019

Recent, state of the art, x-ray spectrometers have made use of polarizing the source x-rays by scattering through 90° (1) . One then observes the analyte fluorescence in a direction perpendicular to the scattering plane in which the polarized x-rays are generated. The signal/noise ratio at the detector is much improved. Unfortunately there is a concomitant loss of intensity and analysis times increase. This adversely affects the minimum detection limits.
XRF Analysis by Combining the Standard Addition Method with Matrix-Correction Models
Authors: De Groot Peter B.
Published: March 2019

The standard addition method is often useful for singleelement analyses in matrices of unknown composition or those difficult to reproduce. Results are good at low concentrations where concentration vs. intensity is approximately linear, but serious errors occur at higher concentrations. A method is shown here for greatly extending the range of the standard addition approach by combining it with with matrix correction models. Expressions incorporating the well-known alpha-or beta-correction coefficients are derived for the observed intensities before and after addition of the analyte. K-ratio measurements on the saraple plus a single standard addition allow the calculation of the correction coefficient and analyte concentration. Several standard addition levels can also be used and concentration obtained from non-linear regression analysis. A computer program has been developed to perform these calculations. Analyses of CuO on silica and of four metals in a metal oxide catalyst over a wide range of concentrations gave results with a relative accuracy generally within ±5%.
Determination of Light Elements on the Chem-X Multichannel Spectrometer
Authors: Gurvich Y.M. , Buman A. , Lokshin I.
Published: March 2019

For X-ray fluorescence determination of light elements, vacuum X-rays spectrometers are usually used to increase the transmission of the optical path for the soft X-radiation. A vacuum of about 50μHg is required for the determination of elements with atomic numbers down to 9(F).

A vacuum system however, complicates the sample presentation mechanism of a spectrometer; it requires vacuum seals, additional fastening of the flow detector window and, as a results, increases the price of the spectrometer.
Mathematical Correction Procedures in XRF - The Long and the Short
Authors: Lachance Gerald R.
Published: March 2019

The processes of absorption and enhancement in x-ray fluorescence spectrometry preclude the direct conversion of measured intensities to concentrations unless the specimens being analyzed are practically identical to the reference materials that were used as standards for calibration. While well known techniques of spectrometry such as the use of internal standards or techniques specific to x-ray fluorescence such as Compton scatter may be used in some instances, the analysis of alloys for example is not amenable to these techniques. The goal of mathematical correction procedures is to compensate adequately for matrix effects and therefore to extend the concentration range within which analysis may be accomplished. The evolution of the concepts and expressions that have been proposed for this purpose spans some 50 years, is somewhat fascinating and examined in outline after a brief nostalgic look at where it all began.
Unification of “Standard Background” Technique using Scattered Radiation in X-Ray Fluorescence Analysis (XRF)
Authors: Smolniakov V. I.
Published: March 2019

Some x-ray fluorescence - concentration relationships in the framework of XRF were researched. Fundamental calculation approaches for primary fluorescence and incoherent scattering were realized for evaluation of matrix influence. A new binary approach was produced for the cases considered, and its unification was related to the empirical and regression types of the “standard background” technique, widely used in the analytical practice of XRF. It is confirmed that application of the calculations by fundamental parameters (FP) in combination with the empirical approach allows the reduction of the set of standards (to as few as one) in the analysis procedure with wide variations in matrices and concentrations, without loss of accuracy.
X-Ray Fluorescence Analysis of Nonhomogeneous Materials by Δμ-Correction Method
Authors: Karmanov V. I. , Zagorodny V. V.
Published: March 2019

The fundamental parameters method (FPM) enables one to determine with high accuracy the chemical composition of homogeneous samples, having only one reference sample. However, the reference sample composition should be similar to that of the samples analyzed.

The x-ray fluorescence analysis of multicomponent heterogeneous materials (ores, minerals, their mixtures, welding electrode coating mixtures, fluxes, etc.) is made by the Δμ-correction method based on the combined use of the fundamental and empirical correlations maintaining all the advantages of the FPM. Sample composition is calculated on the basis of the element intensities measured in the sample and in the reference specimen and is corrected for the disturbing effect of excitation conditions and heterogeneity as well as the calculated values of one of the fundamental parameters (μ1). At the preliminary stage of calibration, the coefficients are determined using regression and the absolute fundamental expression for the element fluorescence intensity.
Depth Profiling by Means of X-Ray Photoelectron Spectrometry
Authors: Ebel M.F. , Ebel H. , Olcaytug F.
Published: March 2019

The depth range d of x-ray photoelectron spectrometry (XPS) is determined by the inelastic mean free path λ of photoelectrons . The following considerations are dedicated to a correlation between d and λ.
Trace Element Analysis using Total-Reflection X-Ray Fluorescence Spectrometry
Authors: Prange Andreas , Schwenke Heinrich
Published: March 2019

For the application of TXRF in trace element analysis, two characteristic features of the total reflection of X-rays are exploited. These are the high reflectivity on flat surfaces and the low penetration depth of the primary radiation. This allows the application of TXRF for both chemical trace and ultra-trace element analysis on the one hand and surface analysis on the other. For chemical trace clement analysis, total reflection on a highly polished substrate is characterized by a high reflectivity, which leads to a drastic reduction of the spectral background. The sample to be analyzed is prepared on the substrate as a residue of small quantities by evaporation from solutions or fine-grained suspensions. Instrumental detection limits of a few pg or sub-ng/ ml−1 arc state of the art for commercially available equipment. Besides the high detection power, internal standardization is another important feature of TXRF, enabling very simple quantification of the detected elements. The small sample mass required enables especially ultra-micro analytical questions to be tackled. For trace element analysis in surfaces the low penetration depth of the primary radiation under the conditions of total reflection is exploited. The penetration depth is in the range of a few nanometers, hence, TXRF is intrinsically surface sensitive. Detection limits better than 1010 atoms/cm2 are obtained for metal impurities on silicon wafers. For the examination of layered structures elemental composition, layer thickness, and density can be derived from die angle-dependent fluorescence intensities. The present paper describes the basic features of the total reflection of X-rays and gives some representative examples of the different uses of TXRF in trace element analysis.
Characterization of Near Surface Layers by Means of Total Reflection X-Ray Fluorescence Spectrometry
Authors: Schwenke H. , Gutschke R. , Knoth J.
Published: March 2019

Total Reflection X-ray Fluorescence Spectrometry (TXRF) has been used for the characterisation of a 20 nm thick Ni/Fe/Cr-layer on a silicon substrate. Instrumental aspects of the technique as well as the data evaluation procedure on the basis of modelling calculations are outlined in this paper. The effect of standing waves is discussed by means of the selected example. This particular layer serves also as an illustration of the capabilities and limitations of TXRF. At least three surface parameters are covered by the technique, elemental composition, density and layer thickness.
Application of Total Reflection X-Ray Fluorescence Spectrometry to Drug Analysis
Authors: Nomura S. , Minomiya T. , Tanlguchi K. , Ikeda S.
Published: March 2019

A new procedure for indirect determination of pharmaceutical drugs is presented. The procedure consists of extracting ion pairs between organic basic compounds, that is, pharmaceutical drugs and cobalt tetrathiocyanate and of determining Co contents in the organic extraction phase using total reflection X-ray fluorescence spectrometry. Quinine, papaverine and pilocarpine are used as pharmaceutical drugs and 1,2-dichloroethane is adopted as extraction medium. Quinine cobalt tetrathiocyanate complex was isolated and was analyzed by FT-IR (Fourier Transform Infra-Red spectroscopy) suggested that approximately 4 ng of quinine could be detected by 1 μl of sampling of organic phase under ideal conditions using total reflection X-ray fluorescence spectrometry. These drugs have their own optimal pH for extraction. This technique can be applied to cocaine analysis.
An Integrated X-Ray Tube - Polarizer EDXRF-Spectrometer in Cartesian Geometry
Authors: Rieder Robert , Wobrauschek Peter , Aiginger Hannes
Published: March 2019

Linear polarized x-rays are used as exciting radiation to reduce the background and to improve the detection limits in XRF. A combination of an x-ray tube and a measuring module realizing a compact cartesian geometry was constructed. An on-line adjustable Bragg-polarizer, a Barkla-polarizer or a secondary target can be used optionally. The anode material of the tube can be changed easily.
Micro-X-Ray Fluorescence Analysis on a Synchrotron Radiation Wiggler Beam Line
Authors: Gilfrich J.V. , Skelton E.F. , Qadri S.B. , Moulton N.E. , Nagel D.J. , Hu J. Z.
Published: March 2019

It has been well established over recent years that synchrotron radiation possesses some unique features as a source of primary x-rays for x-ray fluorescence analysis. Advantage has been taken of the high intensity emanating from the bending magnets of storage rings to develop x-ray microprobes utilizing apertures or focussing optics, or both, to provide a beam spot at the specimen of the order of micrometers. The use of insertion devices wigglers and undulatora, can further increase the available intensity, especially for the high energy photons. Beam Line X-17C at the National Synchrotron Light Source (NSLS) at Brookhaven National Laboratory, accepts the unmodified continuum radiation from a superconducting wiggler in the storage ring. Some initial XRF measurements have been made on this beam line using apertures in the 10 to 100 micrometer range. The fluorescent radiation was measured by an intrinsic Ge detector having an energy resolution of 300 eV at 15 kev, and located at 90° to the incident beam in the plane of the electron orbit. In samples containing many elements, detection limits of a few ppm were achieved with 100 μm beams.
Geometric Considerations in EDXRF to Increase Fluorescence Intensities and Reduce Background
Authors: Tolokonnikoff Igor
Published: March 2019

Two methods for improving the sensitivity of EDXRF will be presented. One method is to use a spherical geometry for the measurements. The analyzed specimen is made as a spherical layer (i.e., “orange rind”), with the exciting x-ray source and the detector being located in the inner surface of the specimen at opposite points on the diameter. The source radiation scattered into the detector is minimized by the 90° scattering angle at all points on the specimen. It has been shown that the sensitivity is improved by several times while earring out EDXRF measurements under conditions of spherical geometry as compared to the conventional flat arrangement.

The other method we have investigated makes use of polarized radiation. The source radiation is polarized by scattering from a thin, low atomic number material. Higher energy radiation from the x-ray tube passes through the polarizer, where it impinges on a secondary fluorescer. This secondary radiation is then polarized by the same scatterer as the primary radiation. A quasi-monoenergetic polarized source is produced with maximized intensity by these means. It has been shown experimentally that the use of this polarized source for excitation leads to detection limits which are several times lower in the whole range of moderate energy. It has further been shown that the use of the easily added secondary target to the standard orthogonal polarization geometry increases the polarized beam intensity by 10-15%.
A Xanes Study of Square Copper(II) Complexes
Authors: Wakita Hisanobu , Yamaguchi Toshio , Adachi Hirohiko , Fujiwara Manabu , Yamashita Seiichi
Published: March 2019

The XANES (X-ray absorption near edge structure) spectra of copper(II) ions in solid state and in solution of the square-planar copper(II) complexes with tetraaza macrocycles were measured. The peaks in the measured XANES spectra shifted to lower energy side with increasing the electron density of central copper(II) ions. The molecular orbital calculations for the complexes were carried out by the DV-Xα method, and the theoretical XANES spectra were estimated. The clear chemical shift obtained by this XANES study is evaluated and leads to a new concept of π-back donation between the copper(II) complexes and counter anion in aqueous solution.
The Study of Valuable Medals using X-Ray Analysis
Authors: Creagh Dudley
Published: March 2019

The exact compositions of the Victoria Crosses held in custody by the Australian War Memorial were needed so that its conservation staff could formulate a proper strategy for their conservation. This analytical study not only provided the required information but it resolved important ambiguities in the historical record.
Fast and Simple Routine Determination of Bromine by XRF in Wet Blood Serum Microsamples Evaluation of Errors
Authors: Shenberg C. , Gilat J. , Mantel M.
Published: March 2019

A specific XRF method, developed at the Soreq Nuclear Research Centre, was applied to the determination of bromine in blood. The method is based on excitation with a Mo X-ray tube and detection of the fluorescent Br K X-rays by a Si (Li) detector. Serum microsamples (300 μL) are counted directly, without drying, for 100 sec, The detection limit obtained under these conditions is 0.6 ppm Br, The overall precision of the method was found to be ±3.1%. The different parameters which contribute to the total error of the method were studied, A survey of the bromine concentration in the blood serum of industrial workers exposed to bromine compounds was carried out.
Stastitical Comparison of Analytical Results Obtained by Pressed Powder and Borate Fusion XRF Spectrometry for Process Control Samples of a Lead Smelter
Authors: Metz Jorg G.H. , Davey David S.
Published: March 2019

Two sample preparation procedures for XRF determination of critical elements in process control samples of a lead smelter have been compared. The two methods, pressed powder(PP) and borate fusion(BF) were used in the analysis of (in order of importance) lead, zinc, copper, sulphur, arsenic and the flux elements (FeO, MnO, Al2O3, CaO, MgO and SiO2). The techniques were applied to three points in the overall lead-zinc-copper production process.

The three sample types have been selected to allow comparison between the BF and PP methods, where the PP method suffers from difficulties with particle size, moisture absorption or composition variation.

The BF technique was found to give better precision (typically 0.2 to 1% RSD) than the PP approach (typically 0.8 to 9% RSD), and to give better accuracy as found using reference materials. The stability of the BF bead over time is also of advantage in quality control. The flexibility and reliability of the BF technique has lead to its acceptance, and in part, to changes in the overall smelter analysis structure.
In-Process Coating Layer Analysis of Galvannealed Steel Sheets with Monochromatic Incident X-Rays
Authors: Kato Hiroharu , Imai Kiyotaka , Tanabe Hideya
Published: March 2019

A new method, for the on-line determination of the composition and the coating weight of galvannealed (Zn-Fe-alloy-coated) steel sheets using monochromatic incident x-rays with two optical systems, is described. In the case of galvannealed steel sheets, it is difficult to determine the composition and the coating weight precisely by simple XRF, because fluorescent x-rays of Iron are emitted not only from the coating layer but also from the underlying steel sheets. We have developed an on-line analyzer with two optical systems which are different in incident angles, take-off angles and wavelengths of monochromatic incident x-rays. We determine the composition and the coating weight by solving simultaneous equations of the data which we derive using two optical systems. Using monochromatic x-rays enabled us to obtain high precision with high speed. We considered en-or factors in on-line measurement such as statistical error or fluctuation of the distance between the sensor head and steel sheets. This on-line analyzer has been applied to the continuous galvanizing line in our Fukuyama works successfully. As a result, we have been able to significantly improve product quality.
Imaging the Three-Dimensional Microstructure of Materials
Authors: Russ John C.
Published: March 2019

Three-dimensional tomographic reconstruction is capable of producing arrays of cubic voxels with resolution adequate to reveal important microstructural properties in materials. Visualization and measurement of these structures extends the types of information available from conventional 2D microscopy.
A New Nondestructive Quantitative Composition Depth Profiling Technique Based on X-Ray Excited Electron Emission
Authors: Backaleinickov L.A. , Konnikov S.G. , Pogrebitsky K.Ju. , Yuriev Y.N. , Vereninov A.A. , Svagera R. , Kaitna R. , Barnegg-Golwig G.
Published: March 2019

The physical basis for x-ray induced secondary electron emission in the range of the absorption edges is described. Applications of this principle for nondestructive composition determination and for nanometer resolved quantitative composition depth profiling are illustrated. A new commercial type of scientific instrument is presented which can be used for this new technique, and for almost all methods that require x-ray photon beam probing.

All the methods described in this paper are based on the same phenomenon, chat is, the phenomenon of the jump-like increase of x-ray photoabsorption in the vicinity of the x-ray absorption edges of the chemical elements of the sample.
Comparison of Synchrotron X-Ray Microanalysis with Electron and Proton Microscopy for Individual Particle Analysis
Authors: Janssens K.H. , van Langevelde F. , Adams F.C. , Vis R.D. , Sutton S.R. , Rivers M.L. , Jones K.W. , Bowen D.K.
Published: March 2019

A considerable number of the elements and a profusion of organic compounds are emitted into the atmosphere in association with solid and liquid particles. More than 50 percent of all air pollutants are preferentially present in particulate matter rather than in the gas phase. The assessment of the potential environmental and toxic effects of particulate matter in the atmosphere requires a detailed physical and chemical characterization. Methods for analyzing aerosols have recently been extensively reviewed by Maenhaut.
A Novel Scanning X-Ray Diffracto-Microscope/X-Ray Powder Diffractometer using Converged X-Ray Beam
Authors: Yukino Ken , Okamura Pujio P. , Biozaki Hiroshi , Kobayashi Yuji , Yamada Yoshiyuki
Published: March 2019

A new type of scanning X-ray diffracto-microscope (SXDM) / X-ray powder diffractometer (XPD) which uses a converged incident beam, was designed, manufactured, and some of its basic characteristics were examined. The optical system consists of asymmetric reflection type curved crystal monochromators for both incident and reflection beams, a detector (FSPC, X-ray film, IP, nuclear plate), a translation mechanism for the specimen and also for the detector.
Development of a High Spatial Resolution X-Ray Fluorescence Element Mapping Spectrometer and its Application to Quantitative Analysis of Biological Systems
Authors: Fukumoto Natsuo , Kobayashi Yoshinori , Kurahashi Masayasu , Kawase Akira
Published: March 2019

We developed an X-ray fluorescence element mapping spectrometer (XEMS) based on commercially available energy dispersive XRF equipment several years ago. Using XEMS, we found that this technique is applicable to realtime observation of the elemental distributions in living biological samples. This kind of observation is almost impossible by conventional techniques such as EPMA, PIXE etc. But the spatial resolution of the previous system was about 200pm, Inferior by almost two orders to that of EPMA for example. So we developed a new spectrometer with an improved resolution of better than 20um and almost the same sensitivity.
Total Reflectance X-Ray Spectrometry
Authors: Aiginger Hannes , Wobrauschek Peter
Published: March 2019

The reduction of the background in x-ray fluorescent spectra is achieved by total reflection of the primary x-rays at a plane, smooth surface of a suitable reflector material. This effect essentially reduces the background caused by scattering of the primary photons from the substrate, thus improving the lower limits of detection in x-ray fluorescence analysis (XRF). Introducing additional to the reflector-substrate another reflector in the primary beam, this affects the spectral distribution of the exciting radiation (“high energy cutoff”). The result is an improved background, where detection limits of picogram amounts or concentrations in the ppb range are attainable for medium Z elements with energy dispersive detectors.
Use of Primary Beam Filtration in Estimating Mass Attenuation Coefficients by Compton Scattering
Authors: O'Connor B. H. , Chang W–J.
Published: March 2019

Mass attenuation coefficients (MACs) are frequently estimated over a range of wavelengths in x-ray spectrometry from the intensity of the Compton peak IC associated with a prominent tube line. The MAC μλ at wavelength λ is estimated from the MAC at the Compton wavelength λC with the approximations μλ α μC and μC α 1/IC. Systematic errors may introduce absorption edge bias (AEB) effects into the results, caused by sample components vith absorption edges between λc and λ. A procedure is described which eliminates AEB effects by measuring IC using emission radiation from a primary beam filter.
A Soft X-ray Experimental Facility
Authors: Gilfrich John V. , Nagel David J. , Fatemi Mohammad , Bleach Richard D. , Hudson Karrol R.
Published: March 2019

A high vacuum soft x-ray source has been coupled to a large volume experimental chamber to provide a versatile facility for x-ray investigations in the energy range of 0.1 to 10 kev. The source chamber presently contains a modified Herike tube, but can employ any of a variety of source designs. The large experimental chamber is equipped with a kinematic mount to position a number of x-ray optical instruments. The source and experimental chambers are connected through a high vacuum valve/shutter, and are pumped separately with provision for a thin window to isolate one from the other, single and double crystal spectrometers have been used in the experimental chamber. A variable chord diffractometer/reflectometer using double crystal monnotiromatization has been designed, in addition, the facility has been used to expose photoresists in x-ray lithography tests.
EDXRF Determination of Major and Minor Elements in Compound Fertilizers
Authors: Christensen Leif Højslet , Rasmussen Leif
Published: March 2019

The combination of the energy-dispersive x-ray fluorescence technique and a backscatter/fundamental parameter-based matrix correction approach provides a new and unique solution to elemental analyses of fertilizers. This is demonstrated by means of results obtained for three reference materials and a range of in-house fertilizers. The results further demonstrate problems of sample preparation as well as the precision and accuracy of the method.
Analysis of Wet-Process Phosphoric Acid and By-Product Filter Cake by X-ray Spectrometry
Authors: Wilhide Wendell D. , Ash Doris H.
Published: March 2019

Rapid X-ray fluorescence (XRF) analytical methods have been developed for analyzing wet-process phosphoric acid liquid samples and by-product calcium sulfate filter-cake solids. Liquid acid samples are neutralized by lithium carbonate and pressed-pellet, dry sample wafers are prepared for a nine-element analysis. Filter-cake solids are dehydrated to anhydrous calcium sulfate for a ten-element analysis. Hovel sample preparation techniques are described which permit maximum use of the automated XRF system for process control. Precision obtained for typical materials is compared with results of conventional chemical analyses.
Balanced Filters for an Annular Counter
Authors: Steinmeyer Peter A.
Published: March 2019

Annular counters are finding increasing application in x-ray diffraction. They are well suited for detection of weak diffracted beams because of their ability to capture an entire Debye ring. This is especially true in the case of microfocus diffractometers, where the Illuminated sample area may be a spot less than 100 microns in diameter. Unfortunately, the geometry of the annular counter precludes the use of a diffracted beam, monochromator. However, near monochromatic conditions can be achieved by using balanced filters to bracket the K alpha line, or any other line of interest. We discuss here the application of balanced filters to the Rigaku microdiffractometer, which uses Debye-Scherrer optics.
X-ray Multiaxial Stress Analysis on Materials with Stress Gradient by Use of Cos Ψ Function
Authors: Yoshioka Yasuo , Sasaki Toshihiko , Kuramoto Makoto
Published: March 2019

When X-ray residual stresses are determined taking into account the stress gradients within the penetration depth of X-rays, three assumptions have usually been made; 1) the stress gradient is linear in respect to the depth from the specimen surface, 2) the penetration depth of X-rays is a function of Sin2ψ and 3) the strain measured by X-rays corresponds to the average strain weighted on the intensity of the diffracted X-rays. However, the assumption of the penetration depth of X-rays is the reason we sometimes observed noticeable errors which depend on the combination of stress components in the stress tensor.