New Standard Reference Materials for X-Ray Powder Diffraction

Advances in X-ray Analysis ◽

10.1154/s037603080001226x ◽

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.

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

MRS Proceedings ◽

10.1557/proc-113-75 ◽

1987 ◽

Vol 113 ◽

Cited By ~ 6

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.

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

Powder Diffraction ◽

10.1017/s0885715600012884 ◽

1987 ◽

Vol 2 (4) ◽

pp. 242-248 ◽

Cited By ~ 35

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.

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

Powder Diffraction ◽

10.1017/s0885715600032899 ◽

1988 ◽

Vol 3 (3) ◽

pp. 156-161 ◽

Cited By ~ 7

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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Standard Reference Materials and Meaningful X-Ray Measurements

Advances in X-ray Analysis ◽

10.1154/s0376030800005140 ◽

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.

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

Powder Diffraction ◽

10.1017/s0885715600011969 ◽

1986 ◽

Vol 1 (4) ◽

pp. 294-298 ◽

Cited By ~ 16

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.

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