{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,13]],"date-time":"2026-06-13T15:24:27Z","timestamp":1781364267521,"version":"3.54.1"},"reference-count":48,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2021,6,5]],"date-time":"2021-06-05T00:00:00Z","timestamp":1622851200000},"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>Environmental monitoring of aquatic systems is the key requirement for sustainable environmental protection and future drinking water supply. The quality of water resources depends on the effectiveness of water treatment plants to reduce chemical pollutants, such as nitrates, pharmaceuticals, or microplastics. Changes in water quality can vary rapidly and must be monitored in real-time, enabling immediate action. In this study, we test the feasibility of a deep UV Raman spectrometer for the detection of nitrate\/nitrite, selected pharmaceuticals and the most widespread microplastic polymers. Software utilizing artificial intelligence, such as a convolutional neural network, is trained for recognizing typical spectral patterns of individual pollutants, once processed by mathematical filters and machine learning algorithms. The results of an initial experimental study show that nitrates and nitrites can be detected and quantified. The detection of nitrates poses some challenges due to the noise-to-signal ratio and background and related noise due to water or other materials. Selected pharmaceutical substances could be detected via Raman spectroscopy, but not at concentrations in the \u00b5g\/l or ng\/l range. Microplastic particles are non-soluble substances and can be detected and identified, but the measurements suffer from the heterogeneous distribution of the microparticles in flow experiments.<\/jats:p>","DOI":"10.3390\/s21113911","type":"journal-article","created":{"date-parts":[[2021,6,7]],"date-time":"2021-06-07T01:56:40Z","timestamp":1623031000000},"page":"3911","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":48,"title":["Application of Laser-Induced, Deep UV Raman Spectroscopy and Artificial Intelligence in Real-Time Environmental Monitoring\u2014Solutions and First Results"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4387-4712","authenticated-orcid":false,"given":"Claudia","family":"Post","sequence":"first","affiliation":[{"name":"Department of Engineering Geology and Hydrogeology, RWTH Aachen University, Lochnerstr. 4-20, 52064 Aachen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Simon","family":"Br\u00fclisauer","sequence":"additional","affiliation":[{"name":"Artha, Wagistrasse 21, CH-8952 Schlieren, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4120-0733","authenticated-orcid":false,"given":"Kryss","family":"Waldschl\u00e4ger","sequence":"additional","affiliation":[{"name":"Institute of Hydraulic Engineering and Water Resources Management, RWTH Aachen University, Mies-van-der-Rohe-Str. 17, 52056 Aachen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"William","family":"Hug","sequence":"additional","affiliation":[{"name":"Photon Systems Inc., 1512 Industrial Park St., Covina, CA 91722-3417, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Luis","family":"Gr\u00fcneis","sequence":"additional","affiliation":[{"name":"Department of Engineering Geology and Hydrogeology, RWTH Aachen University, Lochnerstr. 4-20, 52064 Aachen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Niklas","family":"Heyden","sequence":"additional","affiliation":[{"name":"Department of Engineering Geology and Hydrogeology, RWTH Aachen University, Lochnerstr. 4-20, 52064 Aachen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sebastian","family":"Schmor","sequence":"additional","affiliation":[{"name":"Department of Engineering Geology and Hydrogeology, RWTH Aachen University, Lochnerstr. 4-20, 52064 Aachen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7069-3277","authenticated-orcid":false,"given":"Aaron","family":"F\u00f6rderer","sequence":"additional","affiliation":[{"name":"Department of Engineering Geology and Hydrogeology, RWTH Aachen University, Lochnerstr. 4-20, 52064 Aachen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ray","family":"Reid","sequence":"additional","affiliation":[{"name":"Photon Systems Inc., 1512 Industrial Park St., Covina, CA 91722-3417, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Michael","family":"Reid","sequence":"additional","affiliation":[{"name":"Photon Systems Inc., 1512 Industrial Park St., Covina, CA 91722-3417, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rohit","family":"Bhartia","sequence":"additional","affiliation":[{"name":"Photon Systems Inc., 1512 Industrial Park St., Covina, CA 91722-3417, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Quoc","family":"Nguyen","sequence":"additional","affiliation":[{"name":"Photon Systems Inc., 1512 Industrial Park St., Covina, CA 91722-3417, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0104-0499","authenticated-orcid":false,"given":"Holger","family":"Sch\u00fcttrumpf","sequence":"additional","affiliation":[{"name":"Institute of Hydraulic Engineering and Water Resources Management, RWTH Aachen University, Mies-van-der-Rohe-Str. 17, 52056 Aachen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Florian","family":"Amann","sequence":"additional","affiliation":[{"name":"Department of Engineering Geology and Hydrogeology, RWTH Aachen University, Lochnerstr. 4-20, 52064 Aachen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,6,5]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Goldsmith, A.B. 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