{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T04:17:54Z","timestamp":1760242674294,"version":"build-2065373602"},"reference-count":47,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2016,2,26]],"date-time":"2016-02-26T00:00:00Z","timestamp":1456444800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This work analyzes the long-term functionality of HP (High-power) UV-LEDs (Ultraviolet Light Emitting Diodes) as the exciting light source in non-contact, continuous 24\/7 real-time fluoro-sensing pollutant identification in inland water. Fluorescence is an effective alternative in the detection and identification of hydrocarbons. The HP UV-LEDs are more advantageous than classical light sources (xenon and mercury lamps) and helps in the development of a low cost, non-contact, and compact system for continuous real-time fieldwork. This work analyzes the wavelength, output optical power, and the effects of viscosity, temperature of the water pollutants, and the functional consistency for long-term HP UV-LED working operation. To accomplish the latter, an analysis of the influence of two types 365 nm HP UV-LEDs degradation under two continuous real-system working mode conditions was done, by temperature Accelerated Life Tests (ALTs). These tests estimate the mean life under continuous working conditions of 6200 h and for cycled working conditions (30 s ON &amp; 30 s OFF) of 66,000 h, over 7 years of 24\/7 operating life of hydrocarbon pollution monitoring. In addition, the durability in the face of the internal and external parameter system variations is evaluated.<\/jats:p>","DOI":"10.3390\/s16030293","type":"journal-article","created":{"date-parts":[[2016,2,26]],"date-time":"2016-02-26T10:23:39Z","timestamp":1456482219000},"page":"293","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Functional Analysis in Long-Term Operation of High Power UV-LEDs in Continuous Fluoro-Sensing Systems for Hydrocarbon Pollution"],"prefix":"10.3390","volume":"16","author":[{"given":"Francisco","family":"Arques-Orobon","sequence":"first","affiliation":[{"name":"ETSIST\u2014Technical University of Madrid, Madrid 28031, Spain"}]},{"given":"Neftali","family":"Nu\u00f1ez","sequence":"additional","affiliation":[{"name":"ETSIST\u2014Technical University of Madrid, Madrid 28031, Spain"},{"name":"Instituto de Energ\u00eda Solar\u2014Technical University of Madrid, Madrid 28040, Spain"}]},{"given":"Manuel","family":"Vazquez","sequence":"additional","affiliation":[{"name":"ETSIST\u2014Technical University of Madrid, Madrid 28031, Spain"},{"name":"Instituto de Energ\u00eda Solar\u2014Technical University of Madrid, Madrid 28040, Spain"}]},{"given":"Vicente","family":"Gonzalez-Posadas","sequence":"additional","affiliation":[{"name":"ETSIST\u2014Technical University of Madrid, Madrid 28031, Spain"}]}],"member":"1968","published-online":{"date-parts":[[2016,2,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2453","DOI":"10.3390\/s8042453","article-title":"Absorbance Based Light Emitting Diode Optical Sensors and Sensing Devices","volume":"8","author":"Diamond","year":"2008","journal-title":"Sensors"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"14415","DOI":"10.3390\/s150614415","article-title":"Submersible Spectrofluorometer for Real-Time Sensing of Water Quality","volume":"15","author":"Puiu","year":"2015","journal-title":"Sensors"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"484","DOI":"10.4319\/lom.2014.12.484","article-title":"Characterization and Field Test of an in Situ Multi-Platform Optical Sensor","volume":"12","author":"Ng","year":"2014","journal-title":"Limnol. 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