{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,18]],"date-time":"2026-03-18T14:07:43Z","timestamp":1773842863589,"version":"3.50.1"},"reference-count":34,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2024,3,13]],"date-time":"2024-03-13T00:00:00Z","timestamp":1710288000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001840","name":"Icelandic Centre for Research (RANNIS)","doi-asserted-by":"publisher","award":["217771"],"award-info":[{"award-number":["217771"]}],"id":[{"id":"10.13039\/501100001840","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001840","name":"Icelandic Centre for Research (RANNIS)","doi-asserted-by":"publisher","award":["2020\/37\/B\/ST7\/01448"],"award-info":[{"award-number":["2020\/37\/B\/ST7\/01448"]}],"id":[{"id":"10.13039\/501100001840","id-type":"DOI","asserted-by":"publisher"}]},{"name":"National Science Centre of Poland","award":["217771"],"award-info":[{"award-number":["217771"]}]},{"name":"National Science Centre of Poland","award":["2020\/37\/B\/ST7\/01448"],"award-info":[{"award-number":["2020\/37\/B\/ST7\/01448"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This paper presents high-sensitivity sensors based on an open complementary square split-ring resonator and a modified open complementary split-ring resonator operating at 4.5 GHz and 3.4 GHz, respectively. The sensors are designed for the detection of multiple liquid materials, including distilled water, methanol, and ethanol. The liquid under test is filled in a glass container loaded using a pipette. Compared to the conventional OCSSRR, the modified OCSSRR with multiple rings exhibits a higher frequency shift of 1200 MHz, 1270 MHz, and 1520 MHz for ethanol, methanol, and distilled water, respectively. The modified sensor also demonstrates a high sensitivity of 308 MHz\/RIU for ethanol concentration which is the highest among the existing microwave sensors. The sensors in this manuscript are suitable for multiple liquid-material-sensing applications.<\/jats:p>","DOI":"10.3390\/s24061840","type":"journal-article","created":{"date-parts":[[2024,3,13]],"date-time":"2024-03-13T13:08:43Z","timestamp":1710335323000},"page":"1840","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":14,"title":["Highly Sensitive Microwave Sensors Based on Open Complementary Square Split-Ring Resonator for Sensing Liquid Materials"],"prefix":"10.3390","volume":"24","author":[{"given":"Chandu","family":"Ds","sequence":"first","affiliation":[{"name":"School of Electronics Engineering, VIT-AP University, Amaravati 522237, India"}]},{"given":"K. B. S. Sri","family":"Nagini","sequence":"additional","affiliation":[{"name":"School of Electronics Engineering, VIT-AP University, Amaravati 522237, India"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7691-2485","authenticated-orcid":false,"given":"Rusan Kumar","family":"Barik","sequence":"additional","affiliation":[{"name":"Engineering Optimization and Modeling Center, Reykjavik University, 102 Reykjavik, Iceland"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9063-2647","authenticated-orcid":false,"given":"Slawomir","family":"Koziel","sequence":"additional","affiliation":[{"name":"Engineering Optimization and Modeling Center, Reykjavik University, 102 Reykjavik, Iceland"},{"name":"Faculty of Electronics, Telecommunications and Informatics, Gda\u0144sk University of Technology, 80-233 Gda\u0144sk, Poland"}]}],"member":"1968","published-online":{"date-parts":[[2024,3,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Ray, A.S. (2016). Remote sensing in agriculture. 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