{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,31]],"date-time":"2026-01-31T10:22:35Z","timestamp":1769854955958,"version":"3.49.0"},"reference-count":0,"publisher":"University of Porto","issue":"2","license":[{"start":{"date-parts":[[2020,11,27]],"date-time":"2020-11-27T00:00:00Z","timestamp":1606435200000},"content-version":"unspecified","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["UPjeng"],"abstract":"<jats:p>The study of sensing materials to the detection of carbon dioxide (CO2) was achieved using p-nitrophenol (pNPh) as a colorimetric indicator. The sensing material was polymerized (NPLn), functionalized with 3-triethoxysilyl propyl isocyanate (IPTES) which sensitivity was tested in the form of a membrane as is and encapsulated in hollow silica nanoparticles. The sensing membranes were tested in a closed gas system comprising very precise flow controllers to deliver different concentrations of CO2 (vs. N2). The combination of the sensing membranes with multimode optical fibers and a dual-wavelength diode (LED) allows the measurement of the CO2 through the analysis of the induced absorbance changes with a self-referenced ratiometric scheme. The analysis of the sensing materials have shown significant changes in their chemical and physical properties and the results attest these materials with a strong potential for assessing CO2 dynamics in environmental, medical, and industrial applications.<\/jats:p>","DOI":"10.24840\/2183-6493_006.002_0006","type":"journal-article","created":{"date-parts":[[2020,11,27]],"date-time":"2020-11-27T11:49:16Z","timestamp":1606477756000},"page":"59-69","source":"Crossref","is-referenced-by-count":2,"title":["Colorimetry-based System for Gaseous Carbon Dioxide Detection"],"prefix":"10.24840","volume":"6","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1031-9261","authenticated-orcid":false,"given":"Jo\u00e3o","family":"Mendes","sequence":"first","affiliation":[]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6205-9479","authenticated-orcid":false,"given":"Lu\u00eds","family":"Coelho","sequence":"additional","affiliation":[]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8392-9581","authenticated-orcid":false,"given":"Carlos Manuel","family":"De Melo Pereira","sequence":"additional","affiliation":[]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1484-2068","authenticated-orcid":false,"given":"Pedro","family":"Jorge","sequence":"additional","affiliation":[]}],"member":"10468","published-online":{"date-parts":[[2020,11,27]]},"container-title":["U.Porto Journal of Engineering"],"original-title":[],"link":[{"URL":"https:\/\/journalengineering.fe.up.pt\/article\/download\/2183-6493_006.002_0006\/448","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/journalengineering.fe.up.pt\/article\/download\/2183-6493_006.002_0006\/448","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2020,11,27]],"date-time":"2020-11-27T11:49:23Z","timestamp":1606477763000},"score":1,"resource":{"primary":{"URL":"https:\/\/journalengineering.fe.up.pt\/article\/view\/2183-6493_006.002_0006"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2020,11,27]]},"references-count":0,"journal-issue":{"issue":"2","published-online":{"date-parts":[[2020,11,27]]}},"URL":"https:\/\/doi.org\/10.24840\/2183-6493_006.002_0006","relation":{},"ISSN":["2183-6493"],"issn-type":[{"value":"2183-6493","type":"electronic"}],"subject":[],"published":{"date-parts":[[2020,11,27]]}}}