Flux, J, is a specific quantity. Flux is flow, I [MU·s-1 per system] (an extensive quantity), divided by system size. Flux (e.g., oxygen flux) may be volume-specific (flow per volume [MU·s-1·L-1]), mass-specific (flow per mass [MU·s-1·kg-1]), or marker-specific (e.g. flow per mtEU).
Normalization of rate. (A) Oxygen flow is normalized for (1) the experimental Sample (flow per object, mass-specific flux, or cell-volume-specific flux); or (2) for the Chamber volume. Normalization yields a specific quantity flux from the extensive quantity flow. From Gnaiger 2019 MitoFit Preprint Arch.
MitoPedia methods: Respirometry