{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,30]],"date-time":"2026-01-30T19:45:17Z","timestamp":1769802317879,"version":"3.49.0"},"reference-count":40,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2026,1,29]],"date-time":"2026-01-29T00:00:00Z","timestamp":1769644800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"FCT\u2014Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia\/MECI","award":["UID\/04077\/2025"],"award-info":[{"award-number":["UID\/04077\/2025"]}]},{"name":"national funds from FCT\u2014Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia, I.P.","award":["UID\/50006\/2025"],"award-info":[{"award-number":["UID\/50006\/2025"]}]},{"name":"national funds from FCT\u2014Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia, I.P.","award":["UID\/PRR\/50006\/2025"],"award-info":[{"award-number":["UID\/PRR\/50006\/2025"]}]},{"name":"national funds from FCT\u2014Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia, I.P.","award":["LA\/P\/0008\/2020"],"award-info":[{"award-number":["LA\/P\/0008\/2020"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Metrology"],"abstract":"<jats:p>Anthropogenic CO2 emissions drive ocean acidification through changes in the carbonate system, lowering seawater pH. In contrast, salinity variations arise from physical processes such as freshwater fluxes and circulation. This study reports the preparation and Harned cell characterization of three equimolal TRIS buffer solutions (0.01 mol\u00b7kg\u22121, 0.025 mol\u00b7kg\u22121, and 0.04 mol\u00b7kg\u22121) in artificial seawater (ASW) matrices with practical salinities of 35 and 50 and temperatures of 20 \u00b0C, 25 \u00b0C, and 30 \u00b0C. Determined pHT values achieved expanded uncertainties (UpHT \u2264 0.006), meeting Global Ocean Acidification Observing Network (GOA-ON) \u201cclimate\u201d quality standards. Absolute salinity (SA) was concurrently measured via density (TEOS-10), revealing systematic deviations from practical salinity due to TRIS content. A nonlinear regression model was developed to predict pHT as a function of salinity, temperature, and TRIS molality, with r2 = 0.99998. These results provide a robust dataset for developing Certified Reference Materials (CRMs) for pHT calibration under climate-relevant high-salinity environments at different temperature conditions, offering a practical tool for high-accuracy calibration in variable marine conditions.<\/jats:p>","DOI":"10.3390\/metrology6010006","type":"journal-article","created":{"date-parts":[[2026,1,29]],"date-time":"2026-01-29T10:56:34Z","timestamp":1769684194000},"page":"6","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Metrological Assessment of pHT in TRIS Buffers Within Artificial Seawater: Implications for High-Salinity Reference Materials"],"prefix":"10.3390","volume":"6","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6827-1550","authenticated-orcid":false,"given":"Raquel","family":"Quendera","sequence":"first","affiliation":[{"name":"Departamento de Metrologia, Instituto Portugu\u00eas da Qualidade, R. Ant\u00f3nio Gi\u00e3o, 2, 2829-513 Caparica, Portugal"},{"name":"Chemistry Department, NOVA School of Science and Technology|NOVA FCT, NOVA University of Lisbon, Campus Caparica, 2829-516 Caparica, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4378-5173","authenticated-orcid":false,"given":"Maria Jo\u00e3o","family":"Nunes","sequence":"additional","affiliation":[{"name":"LAQV REQUIMTE, Associated Laboratory for Green Chemistry, Chemistry Department, NOVA School of Science and Technology|NOVA FCT, NOVA University of Lisbon, Lisbon Campus, 2819-516 Caparica, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9270-3982","authenticated-orcid":false,"given":"Ana Lu\u00edsa","family":"Fernando","sequence":"additional","affiliation":[{"name":"LAQV REQUIMTE, Associated Laboratory for Green Chemistry, Chemistry Department, NOVA School of Science and Technology|NOVA FCT, NOVA University of Lisbon, Lisbon Campus, 2819-516 Caparica, Portugal"},{"name":"MEtRICs\/CubicB, Chemistry Department, NOVA School of Science and Technology|NOVA FCT, NOVA University of Lisbon, Campus Caparica, 2829-516 Caparica, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5215-7120","authenticated-orcid":false,"given":"Carla","family":"Palma","sequence":"additional","affiliation":[{"name":"Instituto Hidrogr\u00e1fico, Rua das Trinas, 49, 1249-093 Lisboa, Portugal"}]},{"given":"Sara","family":"Moura","sequence":"additional","affiliation":[{"name":"Departamento de Metrologia, Instituto Portugu\u00eas da Qualidade, R. Ant\u00f3nio Gi\u00e3o, 2, 2829-513 Caparica, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4167-1647","authenticated-orcid":false,"given":"Olivier","family":"Pellegrino","sequence":"additional","affiliation":[{"name":"Departamento de Metrologia, Instituto Portugu\u00eas da Qualidade, R. Ant\u00f3nio Gi\u00e3o, 2, 2829-513 Caparica, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9630-0854","authenticated-orcid":false,"given":"Jo\u00e3o","family":"Alves e Sousa","sequence":"additional","affiliation":[{"name":"Departamento de Metrologia, Instituto Portugu\u00eas da Qualidade, R. Ant\u00f3nio Gi\u00e3o, 2, 2829-513 Caparica, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2026,1,29]]},"reference":[{"key":"ref_1","unstructured":"Raven, J., Caldeira, K., Elderfield, H., Hoegh-Guldberg, O., Liss, P., Riebesell, U., Shepherd, J., Turley, C., Watson, A., and Heap, R. (2005). 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