Elemental concentrations in the National Bureau of Standards' environmental coal and fly ash Standard Reference Materials

1975 ◽  
Vol 47 (7) ◽  
pp. 1102-1109 ◽  
Author(s):  
J. M. Ondov ◽  
W. H. Zoller ◽  
Ilhan. Olmez ◽  
N. K. Aras ◽  
G. E. Gordon ◽  
...  
Keyword(s):  
Fly Ash ◽  
Reference Materials ◽  
Standard Reference Materials ◽  
National Bureau ◽  
Elemental Concentrations

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 Characterization of Three New NBS Fly Ash Standard Reference Materials

1985 ◽  
Vol 65 ◽  
Author(s):  
Howard M. Kanare
Keyword(s):  
Fly Ash ◽  
Reference Materials ◽  
Chemical Elements ◽  
Standard Reference Materials ◽  
Physical Analysis ◽  
National Bureau ◽  
Loss On Ignition ◽  
New Methods ◽  
The U.S

Three new fly ash standard reference materials (SRM's) have been produced by CTL under contract with the U.S. National Bureau of Standards (NBS). Each unit of the SRM's consists of approximately ten grams of well-blended fly ash hermetically sealed in a glass vial. Twenty-thousand vials of each SRM were produced. The SRM's will be certified for major and minor chemical elements, loss on ignition, and for the percentage residue on the No. 325 standard sieve. The SRM's are suitable for use in developing new methods of chemical and physical analysis, for checking the performance of instruments and analysts, and for research into the composition and properties of fly ash.

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.

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.

Measurement and Standard Reference Materials in Clinical Chemistry

1968 ◽  
Vol 14 (10) ◽  
pp. 929-943 ◽  
Author(s):  
Donald S Young ◽  
Thomas W Mears
Keyword(s):  
Uric Acid ◽  
Reference Materials ◽  
Measurement System ◽  
High Purity ◽  
Clinical Chemistry ◽  
Standard Reference Materials ◽  
National Bureau ◽  
Additional Component ◽  
Clinical Laboratories ◽  
Chemical Measurements

Abstract The concepts of the measurement system based upon four parameters—length (meter), mass (kilogram), time (second), and temperature (kelvin)—are developed. The proper daily operation of an analytic laboratory depends upon these basic measurements and others derived from them, e.g., the liter. An additional component of chemical measurement which directly influences accuracy is the purity of the standards and reagents employed. The standard reference materials program of the National Bureau of Standards provides a central source of guaranteed high-purity reference materials which are available to all. The reliability of chemical measurements should increase as new standard reference materials such as cholesterol, uric acid, urea, and creatinine are utilized to standardize methods and to calibrate instruments in the clinical laboratories of this country.

The Microstructure of National Bureau of Standards Reference Fly Ashes

1988 ◽  
Vol 136 ◽  
Author(s):  
J. C. Qian ◽  
E. E. Lachowski ◽  
F. P. Glasser
Keyword(s):  
Electron Microscopy ◽  
Phase Separation ◽  
Fly Ash ◽  
Glassy Phase ◽  
Analytical Electron Microscopy ◽  
Standard Reference Materials ◽  
Chemical Compositions ◽  
National Bureau ◽  
Fly Ashes ◽  
High Iron Content

ABSTRACTA suite of three fly ashes, National Bureau of Standards* Standard Reference Materials (SRMs) 2689, 2690 and 2691, was studied by transmission electron microscopy and by analytical electron microscopy (aem): sample preparation techniques are described. The chemical compositions of the glassy phase, analyzed by aem, showed a wide dispersion of values although the mean composition of the glass remained close to that of the whole fly ash.The microstructure of these materials is complex: besides crystalline inclusions, the aluminasilica glasses have undergone phase separation on a nanometer scale, and consist of two glassy phases. Since liquid-liquid phase separation has also been found in British fly ashes, it appears to be a characteristic feature of the glassy phase in Class F ashes and is also encountered in occasional Al-Si rich particles in Class C ashes. High iron content glass was found in fly ash SRM 2689, and its phase separation and crystallization were investigated.

scholarly journals 230Th-234U model ages of some uranium standard reference materials

2011 ◽  
Vol 1 (1) ◽  
pp. 31-35 ◽  
Author(s):  
R. W. Williams ◽  
A. M. Gaffney
Keyword(s):  
Reference Materials ◽  
Closed System ◽  
Half Life ◽  
Certified Reference Materials ◽  
Isotope Dilution Mass Spectrometry ◽  
Standard Reference Materials ◽  
National Bureau ◽  
System Behavior ◽  
Icp Ms ◽  
Solid Form

Abstract The “age” of a sample of uranium is an important aspect of a nuclear forensic investigation and of the attribution of the material to a source. The 230Th- 234U chronometer can be used to determine the production date of even very recently-produced material ( 234U half life = 245250 ± 490 years; 230Th half life = 75690 ± 230 years [1]), provided that the 230Th/234U at the time of formation is known, and that there has been no Th-U fractionation in the sample since production. For most samples of uranium, ages determined with this chronometer are “model ages”, because they are based on the assumptions of a) some initial amount of 230Th in the sample, and b) closed-system behavior of the sample since production. The uranium standard reference materials originally prepared and distributed by the former US National Bureau of Standards and now distributed by New Brunswick Laboratory as certified reference materials (NBS SRM = NBL CRM) are good candidates for materials where these assumptions may be tested. The U isotopic standards have known purification and production dates and closed-system behavior in the solid form (U3O8) may be reliably assumed. In addition, these materials are widely available and can serve as informal round-robin inter-laboratory comparison samples. We determined 230Th-234U model ages for seven of these isotopic standards by isotope dilution mass spectrometry using a multi-collector ICP-MS. The standards dated for this study are U005-A, U010, U030-A, U100, U850, U900 and U970. Model ages obtained range from ∼ 30 to ∼ 52 years ago (reference date: 5-May-2009). The model age of U100 is the same as the purification date, within uncertainty. The other six standards analyzed all give model ages older than the purification dates of record. The magnitude of the discrepancy between model age and purification date does not correlate with the model age or the amount of 232Th in the samples. This indicates that excess 230Th in these six standards results from incomplete purification during production.

Analysis of Botanical Standard Reference Materials by Cathode Ray Polarography

1972 ◽  
Vol 55 (5) ◽  
pp. 1109-1113
Author(s):  
E June Maienthal
Keyword(s):  
Trace Elements ◽  
Reference Materials ◽  
Sodium Diethyldithiocarbamate ◽  
Standard Reference Materials ◽  
National Bureau ◽  
Nickel Lead

Abstract The need for certified botanical and biological standards both in research and in industrial and field applications is leading to the development and production of a number of new Standard Reference Materials by the National Bureau of Standards. The first of these to be produced and certified is an orchard leaf standard. The determination of a number of important trace elements by cathode ray polarography was investigated and found to offer considerable advantages in sensitivity and accuracy over many other techniques. In addition, several elements may be determined simultaneously in the same solution. The methods were developed and applied to the analysis and certification of nickel, lead, bismuth, and iron in the orchard leaves. Results were also obtained for aluminum which has not yet been certified. Nickel was determined on 1 g samples after extraction with dimethylglyoxime and CHCI3. Lead and bismuth were determined concurrently on 1 g samples after a sodium diethyldithiocarbamate separation. Iron and aluminum were determined on 0.25 g samples after cupferron separations. Details of the methods are given and the results are compared with those obtained by other techniques.

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