The phrase "to emit any fluorescence" means that an object is producing and giving off a glowing light, usually under certain conditions. Full definition
As the zinc shoots out, it binds to small molecules which emit a fluorescence which can be picked up by camera microscopes. (lifenews.com)
In fluorescence microscopy, the sample to be studied is scanned with a strongly focused light beam to make dye molecules emit fluorescence light. (sciencedaily.com)
This used two low - energy (long wavelength) simultaneously - hitting photons to excite a chemical substance that then emitted fluorescence with a «cleaner» signal, than before. (kavliprize.org)