{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,9]],"date-time":"2026-05-09T17:33:27Z","timestamp":1778348007431,"version":"3.51.4"},"reference-count":38,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2018,3,26]],"date-time":"2018-03-26T00:00:00Z","timestamp":1522022400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003329","name":"Ministerio de Econom\u00eda y Competitividad","doi-asserted-by":"publisher","award":["TEC2013-40600-R"],"award-info":[{"award-number":["TEC2013-40600-R"]}],"id":[{"id":"10.13039\/501100003329","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003329","name":"Ministerio de Econom\u00eda y Competitividad","doi-asserted-by":"publisher","award":["TEC2013-41913-P"],"award-info":[{"award-number":["TEC2013-41913-P"]}],"id":[{"id":"10.13039\/501100003329","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003329","name":"Ministerio de Econom\u00eda y Competitividad","doi-asserted-by":"publisher","award":["TEC2016-75650-R"],"award-info":[{"award-number":["TEC2016-75650-R"]}],"id":[{"id":"10.13039\/501100003329","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100002809","name":"Generalitat de Catalunya","doi-asserted-by":"publisher","award":["2014SGR-157"],"award-info":[{"award-number":["2014SGR-157"]}],"id":[{"id":"10.13039\/501100002809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Spanish Junta de Andaluc\u00eda","award":["P12-TIC-1435"],"award-info":[{"award-number":["P12-TIC-1435"]}]},{"DOI":"10.13039\/501100003741","name":"Instituci\u00f3 Catalana de Recerca i Estudis Avan\u00e7ats","doi-asserted-by":"publisher","award":["Award to Ferran Mart\u00edn"],"award-info":[{"award-number":["Award to Ferran Mart\u00edn"]}],"id":[{"id":"10.13039\/501100003741","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100008530","name":"European Regional Development Fund","doi-asserted-by":"publisher","id":[{"id":"10.13039\/501100008530","id-type":"DOI","asserted-by":"publisher"}]},{"name":"China Scolarship Council","award":["201306950011"],"award-info":[{"award-number":["201306950011"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>In this paper, an analytical method to estimate the complex dielectric constant of liquids is presented. The method is based on the measurement of the transmission coefficient in an embedded microstrip line loaded with a complementary split ring resonator (CSRR), which is etched in the ground plane. From this response, the dielectric constant and loss tangent of the liquid under test (LUT) can be extracted, provided that the CSRR is surrounded by such LUT, and the liquid level extends beyond the region where the electromagnetic fields generated by the CSRR are present. For that purpose, a liquid container acting as a pool is added to the structure. The main advantage of this method, which is validated from the measurement of the complex dielectric constant of olive and castor oil, is that reference samples for calibration are not required.<\/jats:p>","DOI":"10.3390\/s18040984","type":"journal-article","created":{"date-parts":[[2018,3,26]],"date-time":"2018-03-26T12:08:25Z","timestamp":1522066105000},"page":"984","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":171,"title":["Analytical Method to Estimate the Complex Permittivity of Oil Samples"],"prefix":"10.3390","volume":"18","author":[{"given":"Lijuan","family":"Su","sequence":"first","affiliation":[{"name":"CIMITEC, Departament d\u2019Enginyeria Electr\u00f2nica, Universitat Aut\u00f2noma de Barcelona, Bellaterra, 08193 Cerdanyola del Valld\u00e8s, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Javier","family":"Mata-Contreras","sequence":"additional","affiliation":[{"name":"CIMITEC, Departament d\u2019Enginyeria Electr\u00f2nica, Universitat Aut\u00f2noma de Barcelona, Bellaterra, 08193 Cerdanyola del Valld\u00e8s, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6502-5987","authenticated-orcid":false,"given":"Paris","family":"V\u00e9lez","sequence":"additional","affiliation":[{"name":"CIMITEC, Departament d\u2019Enginyeria Electr\u00f2nica, Universitat Aut\u00f2noma de Barcelona, Bellaterra, 08193 Cerdanyola del Valld\u00e8s, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1158-6049","authenticated-orcid":false,"given":"Armando","family":"Fern\u00e1ndez-Prieto","sequence":"additional","affiliation":[{"name":"Departamento de Electr\u00f3nica y Electromagnetismo, Universidad de Sevilla, Av. Reina Mercedes s\/n, 41012 Sevilla, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ferran","family":"Mart\u00edn","sequence":"additional","affiliation":[{"name":"CIMITEC, Departament d\u2019Enginyeria Electr\u00f2nica, Universitat Aut\u00f2noma de Barcelona, Bellaterra, 08193 Cerdanyola del Valld\u00e8s, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2018,3,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2075","DOI":"10.1109\/22.798002","article-title":"Magnetism from conductors and enhanced nonlinear phenomena","volume":"47","author":"Pendry","year":"1999","journal-title":"IEEE Trans. Microw. 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