V.I. Dobrovolskiy Al’manac of Modern Metrology № 1 (6) 2016, pages 53–58 The report presents the description, metrological characteristics and application areas of the state primary standards: the pH of the activity of hydrogen ions in aqueous solutions, the activity rate pX ions in aqueous solutions, units of disperse composition of aerosols, suspensions and powders, … Continue reading National primary standards of VNIIFTRI in the field of physicochemical measurements