Standard Reference Materials For X-Ray Diffraction Part II. Calibration Using d-Spacing Standards

1987 ◽  
Vol 2 (4) ◽  
pp. 242-248 ◽  
Author(s):  
W. Wong-Ng ◽  
C. R. Hubbard
Keyword(s):  
Sample Preparation ◽  
Reference Materials ◽  
Theoretical Basis ◽  
Internal Standard ◽  
High Accuracy ◽  
Standard Reference Materials ◽  
National Bureau ◽  
X Ray Diffraction ◽  
X Ray ◽  
External Standard

AbstractExternal standard and internal standard calibrations are important procedures for achieving high accuracy in X-ray powder diffraction studies. The theoretical basis as well as procedures for obtaining calibration curves are given. Methods and examples of selecting Standard Reference Materials (SRMs) which are produced and issued by the National Bureau of Standards (NBS), and procedures of sample preparation with these standards are also described. Three examples are presented to indicate the value of using SRMs.

Standard Reference Materials and Meaningful X-Ray Measurements

1973 ◽  
Vol 17 ◽  
pp. 1-15
Author(s):  
H. Thomas Yolken
Keyword(s):  
Trace Element ◽  
Reference Materials ◽  
Trace Element Analysis ◽  
Silicon Powder ◽  
Standard Reference Materials ◽  
National Bureau ◽  
X Ray Diffraction ◽  
Element Analysis ◽  
X Ray

AbstractA review of the procedures and efforts at the National Bureau of Standards (NBS) to provide for meaningful measurements through the use of Standard Reference Materials (SRM's) is presented.The examples of NBS Standardization efforts for x-ray analysis range from basic metrology to applied environmental measurements. These examples include a determination of x-ray wavelength by a method which in part utilizes simultaneous x-ray and optical interferometry measurements of the atomic planes of near perfect silicon. In addition, Standard Reference Materials (SRM's) are being developed and applied to trace element analysis using x-ray fluorescence techniques. These efforts include development of SRM's for trace element analysis of air particulates. In another area, work is proceeding on the development of a silicon powder Standard Reference Material intended for x-ray diffractometer calibration. An effort to develop a suitable x-ray diffraction technique to determine the amount of quartz in mine dust is also underway. NBS efforts to provide SRM's for the calibration of electron microprobes and the validating of correction factor calculations are also described.

Standard Reference Materials for X-Ray Diffraction Part I. Overview of Current and Future Standard Reference Materials

1986 ◽  
Vol 1 (4) ◽  
pp. 294-298 ◽  
Author(s):  
A. L. Dragoo
Keyword(s):  
Reference Materials ◽  
Line Shape ◽  
Standard Reference Materials ◽  
National Bureau ◽  
X Ray Diffraction ◽  
General Introduction ◽  
Materials Properties ◽  
X Ray ◽  
Intended Use

AbstractStandard Reference Materials (SRM) are stable materials which have one or more properties certified by the National Bureau of Standards. A general introduction is given to the types of SRM's and their certification. SRM's for X-ray diffraction are described in detail, including their intended use and their certified and other properties. New SRM's are under consideration as quantitative standards, intensity and line shape standards, and materials properties standards.

Rietveld quantitative X-ray diffraction analysis of NIST fly ash standard reference materials

2000 ◽  
Vol 15 (3) ◽  
pp. 163-172 ◽  
Author(s):  
Ryan S. Winburn ◽  
Dean G. Grier ◽  
Gregory J. McCarthy ◽  
Renee B. Peterson
Keyword(s):  
Fly Ash ◽  
Diffraction Analysis ◽  
Reference Materials ◽  
Internal Standard ◽  
Standard Reference Materials ◽  
Ratio Method ◽  
X Ray Diffraction ◽  
Crystalline Phases ◽  
X Ray ◽  
High Calcium

Rietveld quantitative X-ray diffraction analysis of the fly ash Standard Reference Materials (SRMs) issued by the National Institute of Standards and Technologies was performed. A rutile (TiO2) internal standard was used to enable quantitation of the glass content, which ranged from 65% to 78% by weight. TheGSASRietveld code was employed. Precision was obtained by performing six replicates of an analysis, and accuracy was estimated using mixtures of fly ash crystalline phases and an amorphous phase. The three low-calcium (ASTM Class F) fly ashes (SRM 1633b, 2689 and 2690) contained four crystalline phases: quartz, mullite, hematite, and magnetite. SRM 1633b also contained a detectable level of gypsum, which is not common for this type of fly ash. The high-calcium (ASTM Class C) fly ash, SRM 2691, had eleven crystalline phases and presented a challenge for the version ofGSASemployed, which permits refinement of only nine crystalline phases. A method of analyzing different groups of nine phases and averaging the results was developed, and tested satisfactorily with an eleven-phase simulated fly ash. The results were compared to reference intensity ratio method semiquantitative analyses reported for most of these SRMs a decade ago.

New Standard Reference Materials for X-Ray Powder Diffraction

1982 ◽  
Vol 26 ◽  
pp. 45-51
Author(s):  
Camden R. Hubbard
Keyword(s):  
Reference Materials ◽  
Nuclear Power ◽  
Standard Reference Materials ◽  
Measurement Technology ◽  
National Bureau ◽  
State Governments ◽  
X Ray ◽  
Ferrous Metals ◽  
Research Organizations ◽  
Improve Measurement

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.

X-Ray Powder Diffraction For Studying the Mineralogy of fly ash

1987 ◽  
Vol 113 ◽  
Author(s):  
Gregory I. McCarthy
Keyword(s):  
Fly Ash ◽  
Powder Diffraction ◽  
Reference Materials ◽  
Standard Reference Materials ◽  
National Bureau ◽  
Fly Ashes ◽  
X Ray ◽  
High Calcium

ABSTRACTA brief summary of the use of x-ray powder diffraction for studying the mineralogy of fly ash is presented. Mineralogies of low-, intermediate- and high-calcium fly ashes are discussed and illustrated by results from XRD characterization of U.S. National Bureau of Standards fly ash Standard Reference Materials.

Preparation and Certification of Standard Reference Materials to be Used in the Determination of Retained Austenite in Steels

1982 ◽  
Vol 26 ◽  
pp. 137-140
Author(s):  
George E. Hicho ◽  
Earl E. Eaton
Keyword(s):  
Reference Materials ◽  
Retained Austenite ◽  
Solid Phase ◽  
Standard Reference Materials ◽  
Face Centered Cubic ◽  
X Ray Diffraction ◽  
X Ray ◽  
Face Centered ◽  
Materials Used ◽  
Steel Hardening

In the steel hardening process, steel is heated to a temperature where a face-centered-cubic solid phase called austenite is formed. After a stabilization period, the steel is quenched into a medium which transforms the austenite into a metastable, body-centered-tetragonal solid phase called martensite. On occasion the austenite is not entirely transformed into martensite and some austenite remains. This untransformed (retained) austenite is sometimes detrimental to the finished product, and often there are requirements as to the amount of retained austenite permitted In the finished product.X-ray diffraction procedures (XRD) are normally used to determine the amount of retained austenite and this paper describes the preparation and characterization of the Standard Reference Materials used to calibrate x-ray diffraction units.

Quantitative X-Ray Diffraction Analysis of Anhydrous and Hydrated Portland Cement - Part 2: Computer-Based Methods

2015 ◽  
Vol 1087 ◽  
pp. 498-503 ◽  
Author(s):  
Duong D. Nguyen ◽  
Liam Devlin ◽  
Pramod Koshy ◽  
Charles C. Sorrell
Keyword(s):  
Portland Cement ◽  
Rietveld Method ◽  
Internal Standard ◽  
Xrd Analysis ◽  
Internal Standard Method ◽  
X Ray Diffraction ◽  
X Ray ◽  
External Standard ◽  
Computer Based ◽  
General Aspects

The present work reviews current practices in quantitative XRD analysis of anhydrous and hydrated Portland cement. While Part 1 of this two-part work reviews the conventional internal standard method and the reference intensity ratio (RIR) method, Part 2 reviews the more commonly used computer-based methods, which include the Rietveld method (with or without internal standard) and the G-factor method (with external standard). Further, some critical general aspects of the experimental procedures that affect the accuracy of the analysis are discussed.

The Application of X-Ray Diffraction for Glass Batch Homogeneity Determination

1981 ◽  
Vol 25 ◽  
pp. 379-382
Author(s):  
H. S. Kim ◽  
C. I. Cohen
Keyword(s):  
Sample Preparation ◽  
Glass Batch ◽  
Reference Sample ◽  
Internal Standard ◽  
Data Sets ◽  
Internal Standard Method ◽  
X Ray Diffraction ◽  
X Ray ◽  
Integrated Intensity ◽  
Quantitative Analyses

AbstractAn X-ray diffraction (XRD) technique is employed to determine the presence or absence of crystalline phases in glass batch and to determine its homogeneity qualitatively and quantitatively.Sample preparation problems are discussed, and promising techniques for sample preparation are presented. Qualitative batch homogeneity determination is accomplished by comparing the integrated intensity of a particular reflection of the reference sample to that of the unknown sample. Quantitative batch determination is accomplished by using the internal standard method. Three replicated data sets indicate that the standard deviation of kaolinite and colemanite are higher than those of quartz and calcite. However, the overall data from the quantitative analyses lie within an acceptable range of precision and accuracy.

The Estimation of Limits of Detection in RIM Quantitative X-Ray Diffraction Analysis

1987 ◽  
Vol 31 ◽  
pp. 317-323
Author(s):  
Briant L. Davis
Keyword(s):  
Sample Preparation ◽  
Theoretical Basis ◽  
Error Propagation ◽  
Limit Of Detection ◽  
X Ray Diffraction ◽  
Preparation Technology ◽  
X Ray ◽  
Counting Statistics ◽  
Absorption Measurements

In earlier papers, the reference intensity method (RIM) of quantitative x-ray diffraction was described in terms of the theoretical basis (Davis, 1980), error propagation (Davis, 1981), filter sample preparation technology for eliminating preferred orientation (Davis and Johnson, 1982; Davis, 1986), and special applications to amorphous-bearing samples using mass absorption measurements (Davis and Johnson, 1987). This paper describes application of counting statistics to the determination of the lower limit of detection (LLD) of components quantitatively measured by the RIM procedure. With this discussion, virtually all phases of the RIM methodology will have been described.

X-Ray Powder Diffraction Study of NBS Fly Ash Standard Reference Materials

1988 ◽  
Vol 3 (3) ◽  
pp. 156-161 ◽  
Author(s):  
Gregory J. McCarthy ◽  
Diane M. Johansen
Keyword(s):  
Fly Ash ◽  
Powder Diffraction ◽  
Reference Materials ◽  
Diffuse Scattering ◽  
Standard Reference Materials ◽  
Phase Assemblage ◽  
National Bureau ◽  
X Ray ◽  
Tricalcium Aluminate ◽  
Ferrite Spinel

AbstractThe fly ash Standard Reference Materials (SRMs) issued by the U.S. National Bureau of Standards have been studied by X-ray powder diffraction (XRD). Based on observations of large diffuse scattering maxima in their X-ray diffractograms, it was evident that all of the ashes had a high glass content. SRM 1633a and 2689, derived from the combustion of bituminous coal, contained different amounts of quartz, mullite, hematite and ferrite spinel (magnetite). SRM 2891, derived from subbituminous coal had quite a different chemical composition and a more complex crystalline phase assemblage, that included these four phases plus anhydrite, tricalcium aluminate, lime, periclase and minor phases. SRM 2690, also derived from subbituminous coal, had only quartz, mullite and ferrite spinel as detectable phases in its diffractogram. Analytical CaO is an important factor in determining the phase assemblage; SRM 2691 had 25.8 wt%, SRM-2690 had 8.0%, and the ash derived from bituminous coals had only 1.6-3.0%. The changing composition of the glass phases in the SRMs is detected in a shift in the position and shape of the diffuse scattering maximum in the diffractograms. Use of an internal intensity standard permitted quantitative comparisons of the relative amounts of crystalline phases among the four fly ash SRMs.

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