Standartnye Obrazcy (Jun 2017)
Development of the state secondary measurement standard and certified reference materials for composition on the basis of liquid and gas chromatography
Abstract
The article is devoted to the development of the state secondary measurement standard of mass fraction units and mass (molar) concentration of organic components in liquid and solid substances and materials based on gas and liquid chromatography. The composition of the state secondary measurement standard, as well as the results of evaluating metrological characteristics have been considered. The problem of ensuring the traceability of measurement results to SI units is given in the article. Two approaches are proposed for obtaining a unit from the state primary standard of mass (molar) fraction units and mass (molar) concentration of organic components in liquid and solid substances and materials based on liquid and gas chromatography-mass spectrometry with isotopic dilution and gravimetry GET 208-2014: by comparing and using transfer standards. Examples of implementing the indicated approaches used during the development of reference materials of toxic substances, namely a certified reference material for composition of p,p-DDT (p,p-DDT, CRM of UNIIM) and a certified reference material for composition of benz(a)pyrene solution in acetonitrile (C20H12, CRM of UNIIM) are given. Results of determining metrological characteristics of reference materials including standard uncertainty due to characterization and standard uncertainties due to inhomogeneity, short and long-term instabilities are described.
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