{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,12]],"date-time":"2026-03-12T05:35:50Z","timestamp":1773293750048,"version":"3.50.1"},"reference-count":24,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2019,12,27]],"date-time":"2019-12-27T00:00:00Z","timestamp":1577404800000},"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":["61535005"],"award-info":[{"award-number":["61535005"]}],"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":["61475069"],"award-info":[{"award-number":["61475069"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"National Science and Technology Major Projects","award":["2017YFC1403803"],"award-info":[{"award-number":["2017YFC1403803"]}]},{"name":"National Science and Technology Major Projects","award":["2017YFA0303700"],"award-info":[{"award-number":["2017YFA0303700"]}]},{"name":"Shenzhen Science and Technology Research Funding","award":["JCYJ20180307155025481"],"award-info":[{"award-number":["JCYJ20180307155025481"]}]},{"name":"the Fundamental Research Funds for the Central Universities","award":["14380160"],"award-info":[{"award-number":["14380160"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>A flexible wireless dielectric sensor is presented here for noninvasively monitoring the permittivity and conductivity of fluids, based on resistor\u2013inductor\u2013capacitor (RLC) resonant circuit and capacitively coupled contactless conductivity detection (C4D) technique. The RLC sensor consists of one single-turn inductor and one interdigital capacitor. The resonant frequency of the device is sensitive to the surrounding environment, thanks to the electric field leaked out between the interdigital capacitor electrodes. Through the high-frequency structure simulator (HFSS) simulation, and experiments on ethanol\/water solutions and NaCl solutions, it was confirmed that a fluid\u2019s permittivity and conductivity could be detected by the return loss curve (S11). With great repeatability and stability, the proposed sensor has potential for broad applications, especially in wearable low-cost smart devices.<\/jats:p>","DOI":"10.3390\/s20010174","type":"journal-article","created":{"date-parts":[[2019,12,27]],"date-time":"2019-12-27T11:42:47Z","timestamp":1577446967000},"page":"174","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["A Flexible Wireless Dielectric Sensor for Noninvasive Fluid Monitoring"],"prefix":"10.3390","volume":"20","author":[{"given":"Heng-Tian","family":"Zhu","sequence":"first","affiliation":[{"name":"College of Engineering and Applied Sciences, Nanjing University, Nanjing 210093, China"}]},{"given":"Ye","family":"Chen","sequence":"additional","affiliation":[{"name":"College of Engineering and Applied Sciences, Nanjing University, Nanjing 210093, China"}]},{"given":"Yi-Feng","family":"Xiong","sequence":"additional","affiliation":[{"name":"College of Engineering and Applied Sciences, Nanjing University, Nanjing 210093, China"}]},{"given":"Fei","family":"Xu","sequence":"additional","affiliation":[{"name":"College of Engineering and Applied Sciences, Nanjing University, Nanjing 210093, China"}]},{"given":"Yan-Qing","family":"Lu","sequence":"additional","affiliation":[{"name":"College of Engineering and Applied Sciences, Nanjing University, Nanjing 210093, China"}]}],"member":"1968","published-online":{"date-parts":[[2019,12,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"532","DOI":"10.3390\/s18020532","article-title":"Low-Cost Wireless Temperature Measurement: Design, Manufacture, and Testing of a PCB-Based Wireless Passive Temperature Sensor","volume":"18","author":"Dan","year":"2018","journal-title":"Sensors"},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Su, S., Lv, W., Zhang, T., Tan, Q., Zhang, W., and Xiong, J. 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