substance fraction, \(x\)

https://doi.org/10.1351/goldbook.S06075
Ratio of the amount-of-substance of the component to the total amount-of-substance in the system containing the component.
Notes:
  1. The term substance fraction is recommended for clinical chemistry, IUPAC also uses @A00296@ and @A00296@.
  2. For clinical chemistry the term @C01209@ is recommended, ISO uses 'substance'.
  3. For clinical chemistry the term @S06234@ is recommended, ISO uses @M03949@.
Source:
PAC, 1996, 68, 957. 'Glossary of terms in quantities and units in Clinical Chemistry (IUPAC-IFCC Recommendations 1996)' on page 994 (https://doi.org/10.1351/pac199668040957)