Value assignment and uncertainty evaluation for anion and single-element reference solutions incorporating historical information.

ABSTRACT: The National Institute of Standards and Technology, which is the national metrology institute of the USA, assigns certified values to the mass fractions of individual elements in single-element solutions, and to the mass fractions of anions in anion solutions, based on gravimetric preparations and instrumental methods of analysis. The instrumental method currently is high-performance inductively coupled plasma optical emission spectroscopy for the single-element solutions, and ion chromatography for the anion solutions. The uncertainty associated with each certified value comprises method-specific components, a component reflecting potential long-term instability that may affect the certified mass fraction during the useful lifetime of the solutions, and a component from between-method dif

SUBMITTER: Lang BE 

PROVIDER: S-EPMC10680025 | biostudies-literature | 2023 Apr

REPOSITORIES: biostudies-literature