number flow rate, q N

https://dx.doi.org/10.1351/goldbook.N04264
Number of defined particles, or elementary entities of a defined component, crossing a cross-section divided by the time.
Source:
PAC, 1996, 68, 957 (Glossary of terms in quantities and units in Clinical Chemistry (IUPAC-IFCC Recommendations 1996)) on page 984