{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,15]],"date-time":"2026-03-15T22:57:32Z","timestamp":1773615452634,"version":"3.50.1"},"reference-count":30,"publisher":"MDPI AG","issue":"17","license":[{"start":{"date-parts":[[2020,8,19]],"date-time":"2020-08-19T00:00:00Z","timestamp":1597795200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Permittivity of materials is of utmost importance for microwave applicators\u2019 design and to predict high-frequency dielectric heating of materials. In the case of aromatic plant biomass, however, there are few data that help researchers design microwave applicators for microwave-assisted extraction. In this work, the permittivity of cypress and rockrose biomass samples were measured versus temperature, density, and moisture content. A resonant technique based on a coaxial bi-reentrant microwave cavity was employed to obtain the complex permittivity of biomass samples as a function of those magnitudes around the 2.45 GHz ISM frequency. The obtained measurements show that large variations for permittivity values can be found with moisture content and density changes for both cypress and rockrose biomass. Temperature also has effects in a lesser degree, although it has an important influence on the cypress biomass loss factor. Polynomial expressions fitting the experimental data were provided in order to facilitate the estimation of intermediate values, which were not explicitly arranged in this work. As a general trend, the permittivity of cypress and rockrose biomass increases with increasing values of moisture content and density, whereas the biomass loss factor increases when temperature rises.<\/jats:p>","DOI":"10.3390\/s20174684","type":"journal-article","created":{"date-parts":[[2020,8,19]],"date-time":"2020-08-19T21:37:40Z","timestamp":1597873060000},"page":"4684","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":16,"title":["Permittivity Measurements for Cypress and Rockrose Biomass Versus Temperature, Density, and Moisture Content"],"prefix":"10.3390","volume":"20","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7120-0283","authenticated-orcid":false,"given":"Rafael","family":"P\u00e9rez-Campos","sequence":"first","affiliation":[{"name":"Departamento de Tecnolog\u00edas de la Informaci\u00f3n y las Comunicaciones, Universidad Polit\u00e9cnica de Cartagena, 30202 Cartagena, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0789-6973","authenticated-orcid":false,"given":"Jos\u00e9","family":"Fayos-Fern\u00e1ndez","sequence":"additional","affiliation":[{"name":"Departamento de Tecnolog\u00edas de la Informaci\u00f3n y las Comunicaciones, Universidad Polit\u00e9cnica de Cartagena, 30202 Cartagena, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3778-8941","authenticated-orcid":false,"given":"Antonio Jos\u00e9","family":"Lozano-Guerrero","sequence":"additional","affiliation":[{"name":"Departamento de Tecnolog\u00edas de la Informaci\u00f3n y las Comunicaciones, Universidad Polit\u00e9cnica de Cartagena, 30202 Cartagena, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8451-250X","authenticated-orcid":false,"given":"Antonio","family":"Mart\u00ednez-Gonz\u00e1lez","sequence":"additional","affiliation":[{"name":"Departamento de Tecnolog\u00edas de la Informaci\u00f3n y las Comunicaciones, Universidad Polit\u00e9cnica de Cartagena, 30202 Cartagena, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6449-8985","authenticated-orcid":false,"given":"Juan","family":"Monz\u00f3-Cabrera","sequence":"additional","affiliation":[{"name":"Departamento de Tecnolog\u00edas de la Informaci\u00f3n y las Comunicaciones, Universidad Polit\u00e9cnica de Cartagena, 30202 Cartagena, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2259-691X","authenticated-orcid":false,"given":"Irene","family":"Mediavilla","sequence":"additional","affiliation":[{"name":"Centro de Desarrollo de Energ\u00edas Renovables, CEDER-CIEMAT, 42290 Lubia, Spain"}]},{"given":"David","family":"Pe\u00f1a-Carro","sequence":"additional","affiliation":[{"name":"Centro de Desarrollo de Energ\u00edas Renovables, CEDER-CIEMAT, 42290 Lubia, Spain"}]},{"given":"Luis Sa\u00fal","family":"Esteban-Pascual","sequence":"additional","affiliation":[{"name":"Centro de Desarrollo de Energ\u00edas Renovables, CEDER-CIEMAT, 42290 Lubia, Spain"}]}],"member":"1968","published-online":{"date-parts":[[2020,8,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Selim, S.A., Adam, M.E., Hassan, S.M., and Albalawi, A.R. 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