Editing Ultraviolet (section)

==== Chemistry ====
[[UV/Vis spectroscopy]] is widely used as a technique in [[chemistry]] to analyze [[chemical structure]], the most notable one being [[conjugated system]]s. UV radiation is often used to excite a given sample where the fluorescent emission is measured with a [[spectrofluorometer]]. In biological research, UV radiation is used for [[quantification of nucleic acids]] or [[protein]]s. In environmental chemistry, UV radiation could also be used to detect [[Contaminants of emerging concern]] in water samples.<ref name="ReferenceA" />

In pollution control applications, ultraviolet analyzers are used to detect emissions of nitrogen oxides, sulfur compounds, mercury, and ammonia, for example in the flue gas of fossil-fired power plants.<ref>
{{cite book
 |editor-first=N.E. |editor-last=Battikha
 |year=2007
 |title=The Condensed Handbook of Measurement and Control
 |edition=3rd |pages=65–66
 |publisher=ISA
 |isbn=978-1-55617-995-2
}}
</ref> Ultraviolet radiation can detect thin sheens of [[oil spill|spilled oil]] on water, either by the high reflectivity of oil films at UV wavelengths, fluorescence of compounds in oil, or by absorbing of UV created by [[Raman scattering]] in water.<ref>
{{cite book
 |editor-first=Mervin |editor-last=Fingas
 |year=2011 |title=Oil Spill Science and Technology
 |pages=123–124
 |publisher=Elsevier
 |isbn=978-1-85617-943-0
}}</ref> UV absorbance can also be used to quantify contaminants in wastewater. Most commonly used 254&nbsp;nm UV absorbance is generally used as a surrogate parameters to quantify NOM.<ref name="ReferenceA">{{Cite journal |last1=Lee |first1=Brandon Chuan Yee |last2=Lim |first2=Fang Yee |last3=Loh |first3=Wei Hao |last4=Ong |first4=Say Leong |last5=Hu |first5=Jiangyong |date=January 2021 |title=Emerging Contaminants: An Overview of Recent Trends for Their Treatment and Management Using Light-Driven Processes |journal=Water |language=en |volume=13 |issue=17 |pages=2340 |doi=10.3390/w13172340 |issn=2073-4441 |doi-access=free |bibcode=2021Water..13.2340L }}</ref> Another form of light-based detection method uses a wide spectrum of excitation emission matrix (EEM) to detect and identify contaminants based on their flourense properties.<ref name="ReferenceA"/><ref>{{Cite web |title=What is an Excitation Emission Matrix (EEM)? |url=https://www.horiba.com/int/scientific/technologies/fluorescence-spectroscopy/what-is-an-excitation-emission-matrix-eem/ |access-date=2023-07-10 |website=horiba.com |language=en |archive-date=10 July 2023 |archive-url=https://web.archive.org/web/20230710083853/https://www.horiba.com/int/scientific/technologies/fluorescence-spectroscopy/what-is-an-excitation-emission-matrix-eem/ |url-status=live }}</ref> EEM could be used to discriminate different groups of NOM based on the difference in light emission and excitation of fluorophores. NOMs with certain molecular structures are reported to have fluorescent properties in a wide range of excitation/emission wavelengths.<ref>{{Cite journal |last1=Sierra |first1=M.M.D. |last2=Giovanela |first2=M. |last3=Parlanti |first3=E. |last4=Soriano-Sierra |first4=E.J. |date=February 2005 |title=Fluorescence fingerprint of fulvic and humic acids from varied origins as viewed by single-scan and excitation/emission matrix techniques |url=http://dx.doi.org/10.1016/j.chemosphere.2004.09.038 |journal=Chemosphere |volume=58 |issue=6 |pages=715–733 |doi=10.1016/j.chemosphere.2004.09.038 |pmid=15621185 |bibcode=2005Chmsp..58..715S |issn=0045-6535 |access-date=10 July 2023 |archive-date=29 May 2024 |archive-url=https://web.archive.org/web/20240529134758/https://www.sciencedirect.com/science/article/abs/pii/S0045653504008185?via%3Dihub |url-status=live |url-access=subscription }}</ref><ref name="ReferenceA"/>

[[File:Fluorescent minerals hg.jpg|thumb|right|A collection of mineral samples fluorescing brilliantly at various wavelengths as seen while being irradiated by UV]]
Ultraviolet lamps are also used as part of the analysis of some [[mineral]]s and [[gems]].