{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T04:38:33Z","timestamp":1760243913813,"version":"build-2065373602"},"reference-count":25,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2010,5,26]],"date-time":"2010-05-26T00:00:00Z","timestamp":1274832000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>A novel multipass photoacoustic cell with five stacked electromechanical films as a microphone has been constructed, tested and characterized. The photoacoustic cell is an open rectangular structure with two steel plates facing each other. The longitudinal acoustic resonances are excited transversely in an optical multipass configuration. A detection limit of 22 ppb (10\u22129) was achieved for flowing NO2 in N2 at normal pressure by using the maximum of 70 laser beams between the resonator plates. The corresponding minimum detectable absorption and the normalized noise-equivalent absorption coefficients were 2:2 \u00d7 10\u22127 cm\u22121 and 3:2 \u00d7 10\u22129 cm\u22121WHz\u22121\/2, respectively.<\/jats:p>","DOI":"10.3390\/s100605294","type":"journal-article","created":{"date-parts":[[2010,5,26]],"date-time":"2010-05-26T11:12:08Z","timestamp":1274872328000},"page":"5294-5307","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Transversely Excited Multipass Photoacoustic Cell Using Electromechanical Film as Microphone"],"prefix":"10.3390","volume":"10","author":[{"given":"Jaakko","family":"Saarela","sequence":"first","affiliation":[{"name":"Optics Laboratory, Department of Physics, Tampere University of Technology, P.O. Box 692, FI-33101 Tampere, Finland"}]},{"given":"Johan","family":"Sand","sequence":"additional","affiliation":[{"name":"Optics Laboratory, Department of Physics, Tampere University of Technology, P.O. Box 692, FI-33101 Tampere, Finland"}]},{"given":"Tapio","family":"Sorvaj\u00e4rvi","sequence":"additional","affiliation":[{"name":"Optics Laboratory, Department of Physics, Tampere University of Technology, P.O. Box 692, FI-33101 Tampere, Finland"}]},{"given":"Albert","family":"Manninen","sequence":"additional","affiliation":[{"name":"Optics Laboratory, Department of Physics, Tampere University of Technology, P.O. 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