modulation frequency

in comprehensive chromatography
symbol: $f_{\rm{M}}$
https://doi.org/10.1351/goldbook.09955
Number of modulations in a given time interval.
Source:
PAC, 2017, 90, 181. 'Terminology of separation methods (IUPAC Recommendations 2017)' on page 208 (https://doi.org/10.1515/pac-2017-0111)