Differential change in concentration of a component in a given direction in a small distance divided by the distance in that direction.
Notes: - It is a vector quantity.
- May be expressed as amount-of-substance, mass, number, volume, concentration @G02669@.
Source:
PAC, 1996, 68, 957. 'Glossary of terms in quantities and units in Clinical Chemistry (IUPAC-IFCC Recommendations 1996)' on page 967 (https://doi.org/10.1351/pac199668040957)