Fluorescence is a luminescence phenomenon in which electron returns to it's ground state almost instantaneously (less than 10-8 second), and in which emission from a luminescent substance ceases when the exciting source is removed. Fluorescence is characterized by radiation emission in all directions.
Generalic, Eni. "Fluorescence." Croatian-English Chemistry Dictionary & Glossary. 29 June 2022. KTF-Split. {Date of access}. <https://glossary.periodni.com>.
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