diffusion current constant in polarography

The empirical quantity defined by the equation

$i = i d , l c B m 2 3 t 1 1 6$

where $i d , l$ = limiting diffusion current, $c B$ = bulk concentration of the substance B whose reduction or oxidation is responsible for the wave in question, $m$ = average rate of (mass) flow of mercury (or other liquid metal) and $t 1$ = drop time.

Source:

PAC, 1985, 57, 1491 (Recommended terms, symbols, and definitions for electroanalytical chemistry (Recommendations 1985)) on page 1500