Standard SRM

Certification and Use of Acidic Potassium Dichromate Solution as an Ultraviolet Absorbance Standard, SRM 935, NIST Spec. Publ. 260-54, 1977. 

In sample 3, which was only sent to certain laboratories, the results may be somewhat clearer. This sample is a standard reference material from the U. S. National Bureau of Standards (SRM 124c). It is an ounce metal with a nominal composition of 85-5-5-5—that is, 85% Cu and 5%... 

A similar set of experiments was performed to test our ability to precisely characterize strontium isotopes. For the archaeological chemistry of biological remains, strontium isotopes are useful for testing dietary hypotheses and for examining differences in place of birth and place of residence. To test the precision of strontium isotope ratio measurement using TOF-ICP-MS, we made glass fusion beads using NIST Strontium Carbonate Standard SRM 987 and... 

Element Nuclide Gamma Ray Energy (keV) Cone, in Standard SRM 1633a CounP3 Analytical Precision SRM 679 RNL to SI Conversion Factors... 

Standard reference materials from the National Institute of Standards and Technology (NIST) are available for RFLP Profiling (SRM 2390), PCR-based Profiling DNA standard (SRM 2391b), Y-chromosome testing (SRM 2395), and mtDNA testing. Standards require annual NIST-traceable comparisons. 

Table 1 Fig. 9). In order to compare results from different studies, Sr/ Sr ratios were adjusted to a value of 0.71024 relative to the Sr isotopic standard SRM 987 (formerly NBS 987). 

Christensen-Dalsgaard J (1998) The standard Srm— Modelling and helioseismology. Space Sci Rev 85 ... 

X-ray powder diffraction patterns were obtained with a Philips AFD 3600 diffractometer (graphite monochrometer and theta-compensating silts) using Cu-Ka radiation and a scan rate of 2 deg 20 mln l The reported line positions were corrected using an Internal silicon standard (SRM-640b). Y-123 concentrations were calculated by... 

Accuracy on the Standard SRM-981 From the compilation, it is obvious that all MC-ICP-MS (Tl-normalized) data plots slightly below those obtained by... 

Table II shows the precision and accuracy of the ICP-MS for tiie four lead isotopes b, Pb, and Pb based on measuremmits of the NIST Common Lead Isotopic Standard (SRM 981). For all of die lead isotopes except for b, our necision is under 0.2%, ai our percent error, or accuracy, is roughly 0.2%. This is etqiected, as Pb is the least abundant lead isotope, and in our analyses we measured amounts of ° Pb that w smaller than counts for the other isotopes by qq oximately a frctor of ten. In addititm, previous research used Pb Pb versus b/ Pb to identity clusters of majolica pottery manufactured in different areas 14), and it is with these isotopes that our method has its best precision and accuracy.

Chang T, Kahn AH. Standard reference materials electron paramagnetic resonance intensity standards SRM 2601, description and use. NIST s special publication 1978 260-59,38 5. 

Introduce the QC standard SRM 1838 in the same manner as the calibration standards. Calculate the percent oxygen (m/m) as described in Section 10. 

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