Pushing the Metrological Frontiers of NAA: A Thirty-Year Effort to Improve Accuracy, Uncertainty and Detection Limits, invited

摘要

Although the first use of NAA at NBS/NIST to certify a Standard Reference Material (SRM) was nearly 40 years ago, INAA and RNAA measurement uncertainties (other than precision) were originally not considered. This began to change about thirty years ago, when the first effort to evaluate all uncertainty components for an INAA certification of an SRM was attempted for the NBS Urban Particulate Matter, SRM 1648 (1). Since that time, efforts have continued to understand, quantify, reduce, and document all uncertainty components for NAA measurements to the point where NAA could be considered a "Primary Method of Measurement" as defined by the VIM (2).