{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,12]],"date-time":"2026-05-12T19:19:31Z","timestamp":1778613571259,"version":"3.51.4"},"reference-count":77,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2022,2,2]],"date-time":"2022-02-02T00:00:00Z","timestamp":1643760000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Ministerio de Econom\u00eda y Competitividad (MINECO) and by European Social Funds (ESF)","award":["BES-2016-077296"],"award-info":[{"award-number":["BES-2016-077296"]}]},{"name":"Ministerio de Econom\u00eda y Competitividad (MINECO) and by European Regional Development Funds (ERDF)","award":["SEDMICRON\u2014TEC2015-70272-R"],"award-info":[{"award-number":["SEDMICRON\u2014TEC2015-70272-R"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The identification of the minerals composing rocks and their dielectric characterization is essential for the utilization of microwave energy in the rock industry. This paper describes the use of a near-field scanning microwave microscope with enhanced sensitivity for non-invasive measurements of permittivity maps of rock specimens at the micrometer scale in non-contact mode. The microwave system comprises a near-field probe, an in-house single-port vectorial reflectometer, and all circuitry and software needed to make a stand-alone, portable instrument. The relationship between the resonance parameters of the near-field probe and the dielectric properties of materials was determined by a combination of classical cavity perturbation theory and an image charge model. The accuracy of this approach was validated by a comparison study with reference materials. The device was employed to determine the permittivity maps of a couple of igneous rock specimens with low-loss and high-loss minerals. The dielectric results were correlated with the minerals comprising the samples and compared with the dielectric results reported in the literature, with excellent agreements.<\/jats:p>","DOI":"10.3390\/s22031138","type":"journal-article","created":{"date-parts":[[2022,2,6]],"date-time":"2022-02-06T20:40:18Z","timestamp":1644180018000},"page":"1138","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["High-Resolution Detection of Rock-Forming Minerals by Permittivity Measurements with a Near-Field Scanning Microwave Microscope"],"prefix":"10.3390","volume":"22","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-8586-3689","authenticated-orcid":false,"given":"Jos\u00e9 D.","family":"Guti\u00e9rrez-Cano","sequence":"first","affiliation":[{"name":"Institute of Information and Communication Technologies (ITACA), Universitat Polit\u00e8cnica de Val\u00e8ncia, Camino de Vera s\/n, 46022 Valencia, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0617-1762","authenticated-orcid":false,"given":"Jos\u00e9 M.","family":"Catal\u00e1-Civera","sequence":"additional","affiliation":[{"name":"Institute of Information and Communication Technologies (ITACA), Universitat Polit\u00e8cnica de Val\u00e8ncia, Camino de Vera s\/n, 46022 Valencia, Spain"}]},{"given":"Angel M.","family":"L\u00f3pez-Buend\u00eda","sequence":"additional","affiliation":[{"name":"CEINNMAT Innovaciones, INNCEINNMAT, SL, C\/Catedr\u00e1tico Agust\u00edn Escardino, 9, 46980 Valencia, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2623-0782","authenticated-orcid":false,"given":"Pedro J.","family":"Plaza-Gonz\u00e1lez","sequence":"additional","affiliation":[{"name":"Institute of Information and Communication Technologies (ITACA), Universitat Polit\u00e8cnica de Val\u00e8ncia, Camino de Vera s\/n, 46022 Valencia, Spain"}]},{"given":"Felipe L.","family":"Penaranda-Foix","sequence":"additional","affiliation":[{"name":"Institute of Information and Communication Technologies (ITACA), Universitat Polit\u00e8cnica de Val\u00e8ncia, Camino de Vera s\/n, 46022 Valencia, Spain"}]}],"member":"1968","published-online":{"date-parts":[[2022,2,2]]},"reference":[{"key":"ref_1","unstructured":"Susilowati, Y., Rahyuwibowo, H., and Mengko, T.R. 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