{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,13]],"date-time":"2026-02-13T23:32:44Z","timestamp":1771025564407,"version":"3.50.1"},"reference-count":33,"publisher":"MDPI AG","issue":"15","license":[{"start":{"date-parts":[[2024,7,27]],"date-time":"2024-07-27T00:00:00Z","timestamp":1722038400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["62001398"],"award-info":[{"award-number":["62001398"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["2023YFB4603500"],"award-info":[{"award-number":["2023YFB4603500"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["KCXTD2024-2"],"award-info":[{"award-number":["KCXTD2024-2"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["2022NSFSC0562"],"award-info":[{"award-number":["2022NSFSC0562"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100012166","name":"National Key Research and Development Program of China","doi-asserted-by":"publisher","award":["62001398"],"award-info":[{"award-number":["62001398"]}],"id":[{"id":"10.13039\/501100012166","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100012166","name":"National Key Research and Development Program of China","doi-asserted-by":"publisher","award":["2023YFB4603500"],"award-info":[{"award-number":["2023YFB4603500"]}],"id":[{"id":"10.13039\/501100012166","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100012166","name":"National Key Research and Development Program of China","doi-asserted-by":"publisher","award":["KCXTD2024-2"],"award-info":[{"award-number":["KCXTD2024-2"]}],"id":[{"id":"10.13039\/501100012166","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100012166","name":"National Key Research and Development Program of China","doi-asserted-by":"publisher","award":["2022NSFSC0562"],"award-info":[{"award-number":["2022NSFSC0562"]}],"id":[{"id":"10.13039\/501100012166","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Innovation Team Funds of China West Normal University","award":["62001398"],"award-info":[{"award-number":["62001398"]}]},{"name":"Innovation Team Funds of China West Normal University","award":["2023YFB4603500"],"award-info":[{"award-number":["2023YFB4603500"]}]},{"name":"Innovation Team Funds of China West Normal University","award":["KCXTD2024-2"],"award-info":[{"award-number":["KCXTD2024-2"]}]},{"name":"Innovation Team Funds of China West Normal University","award":["2022NSFSC0562"],"award-info":[{"award-number":["2022NSFSC0562"]}]},{"name":"Nature Science Foundation of Sichuan Province","award":["62001398"],"award-info":[{"award-number":["62001398"]}]},{"name":"Nature Science Foundation of Sichuan Province","award":["2023YFB4603500"],"award-info":[{"award-number":["2023YFB4603500"]}]},{"name":"Nature Science Foundation of Sichuan Province","award":["KCXTD2024-2"],"award-info":[{"award-number":["KCXTD2024-2"]}]},{"name":"Nature Science Foundation of Sichuan Province","award":["2022NSFSC0562"],"award-info":[{"award-number":["2022NSFSC0562"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This paper proposes a high-sensitivity microstrip differential sensor for measuring the complex permittivity of liquids. The prototype of the differential sensor was formed by cascading two LC resonators on a microstrip transmission line based on stepped impedance. A strong electric field was found to be distributed in the circular patch of the LC resonator; therefore, a cylindrical micropore was set in the center of the circular LC resonator to measure the dielectric sample, which maximized the disturbance of the dielectric sample on the sensor. By optimizing the size of the circular LC resonator, a high-sensitivity sensor circuit was designed and manufactured. The complex permittivity of the test sample was calculated by measuring the transmission coefficient of different molar concentrations of ethanol\u2013water solutions. The experimental results show that the designed differential sensor can accurately measure the complex permittivity of liquid materials with an average sensitivity of 0.76%.<\/jats:p>","DOI":"10.3390\/s24154877","type":"journal-article","created":{"date-parts":[[2024,7,29]],"date-time":"2024-07-29T12:27:43Z","timestamp":1722256063000},"page":"4877","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["High-Sensitivity Differential Sensor for Characterizing Complex Permittivity of Liquids Based on LC Resonators"],"prefix":"10.3390","volume":"24","author":[{"given":"Zhongjun","family":"Li","sequence":"first","affiliation":[{"name":"School of Electronic Information Engineering, China West Normal University, Nanchong 637002, China"},{"name":"College of Electronics and Information Engineering, Sichuan University, Chengdu 610064, China"}]},{"given":"Shuang","family":"Tian","sequence":"additional","affiliation":[{"name":"School of Electronic Information Engineering, China West Normal University, Nanchong 637002, China"}]},{"given":"Jiaxin","family":"Tang","sequence":"additional","affiliation":[{"name":"School of Electronic Information Engineering, China West Normal University, Nanchong 637002, China"}]},{"given":"Weichao","family":"Yang","sequence":"additional","affiliation":[{"name":"School of Electronic Information Engineering, China West Normal University, Nanchong 637002, China"}]},{"given":"Tao","family":"Hong","sequence":"additional","affiliation":[{"name":"School of Electronic Information Engineering, China West Normal University, Nanchong 637002, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1737-870X","authenticated-orcid":false,"given":"Huacheng","family":"Zhu","sequence":"additional","affiliation":[{"name":"College of Electronics and Information Engineering, Sichuan University, Chengdu 610064, China"}]}],"member":"1968","published-online":{"date-parts":[[2024,7,27]]},"reference":[{"key":"ref_1","first-page":"1","article-title":"Permittivity characterization of dispersive materials using power measurements","volume":"70","author":"Mosavirik","year":"2021","journal-title":"IEEE Trans. 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