{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,19]],"date-time":"2026-01-19T06:07:31Z","timestamp":1768802851115,"version":"3.49.0"},"reference-count":49,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2023,8,11]],"date-time":"2023-08-11T00:00:00Z","timestamp":1691712000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Component 5\u2014Capitalization and Business Innovation","award":["56"],"award-info":[{"award-number":["56"]}]},{"name":"Component 5\u2014Capitalization and Business Innovation","award":["UI\/BD152695\/2022"],"award-info":[{"award-number":["UI\/BD152695\/2022"]}]},{"name":"Component 5\u2014Capitalization and Business Innovation","award":["SFRH\/BD130674\/2017"],"award-info":[{"award-number":["SFRH\/BD130674\/2017"]}]},{"name":"Component 5\u2014Capitalization and Business Innovation","award":["CEECIND\/00471\/2017"],"award-info":[{"award-number":["CEECIND\/00471\/2017"]}]},{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia","doi-asserted-by":"publisher","award":["56"],"award-info":[{"award-number":["56"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia","doi-asserted-by":"publisher","award":["UI\/BD152695\/2022"],"award-info":[{"award-number":["UI\/BD152695\/2022"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia","doi-asserted-by":"publisher","award":["SFRH\/BD130674\/2017"],"award-info":[{"award-number":["SFRH\/BD130674\/2017"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia","doi-asserted-by":"publisher","award":["CEECIND\/00471\/2017"],"award-info":[{"award-number":["CEECIND\/00471\/2017"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Chemosensors"],"abstract":"<jats:p>Reinforced concrete structures are prevalent in infrastructure and are of significant economic and social importance to humanity. However, they are prone to decay from cement paste carbonation. pH sensors have been developed to monitor cement paste carbonation, but their adoption by the industry remains limited. This work introduces two new methods for monitoring cement paste carbonation in real time that have been validated through the accelerated carbonation of cement paste samples. Both configurations depart from traditional pH monitoring. In the first configuration, the carbonation depth of a cement paste sample is measured using two CO2 optical fiber sensors. One sensor is positioned on the surface of the sample, while the other is embedded in the middle. As the carbonation depth progresses and reaches the embedded CO2 sensor, the combined response of the sensors changes. In the second configuration, a multimode fiber is embedded within the paste, and its carbonation is monitored by observing the increase in reflected light intensity (1.6\u201318%) resulting from the formation of CaCO3. Its applicability in naturally occurring carbonation is tested at concentrations of 3.2% CO2, and the influence of water is positively evaluated; thus, this setup is suitable for real-world testing and applications.<\/jats:p>","DOI":"10.3390\/chemosensors11080449","type":"journal-article","created":{"date-parts":[[2023,8,11]],"date-time":"2023-08-11T12:10:23Z","timestamp":1691755823000},"page":"449","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Real-Time Monitoring of Cement Paste Carbonation with In Situ Optical Fiber Sensors"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7934-6466","authenticated-orcid":false,"given":"Pedro M.","family":"da Silva","sequence":"first","affiliation":[{"name":"INESC TEC\u2014Institute for Systems and Computer Engineering, Technology and Science and Faculty of Sciences, University of Porto, 4169-007 Porto, Portugal"},{"name":"Faculty of Engineering, University of Porto, 4200-465 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1031-9261","authenticated-orcid":false,"given":"Jo\u00e3o P.","family":"Mendes","sequence":"additional","affiliation":[{"name":"INESC TEC\u2014Institute for Systems and Computer Engineering, Technology and Science and Faculty of Sciences, University of Porto, 4169-007 Porto, Portugal"},{"name":"CIQUP\u2014Chemistry Research Unit, Chemistry and Biochemistry Department, Faculty of Sciences, University of Porto, 4169-007 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6205-9479","authenticated-orcid":false,"given":"Lu\u00eds C. C.","family":"Coelho","sequence":"additional","affiliation":[{"name":"INESC TEC\u2014Institute for Systems and Computer Engineering, Technology and Science and Faculty of Sciences, University of Porto, 4169-007 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3810-5943","authenticated-orcid":false,"given":"Jos\u00e9 M. M. M.","family":"de Almeida","sequence":"additional","affiliation":[{"name":"INESC TEC\u2014Institute for Systems and Computer Engineering, Technology and Science and Faculty of Sciences, University of Porto, 4169-007 Porto, Portugal"},{"name":"Department of Physics, School of Sciences and Technology, University of Tr\u00e1s-os-Montes e Alto Douro, 5001-801 Vila Real, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2023,8,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1349","DOI":"10.1016\/S0008-8846(00)00365-3","article-title":"Cements of Yesterday and Today","volume":"30","year":"2000","journal-title":"Cem. 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