{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T02:13:00Z","timestamp":1760148780920,"version":"build-2065373602"},"reference-count":26,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2023,6,9]],"date-time":"2023-06-09T00:00:00Z","timestamp":1686268800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Science Foundation of China","award":["51707028","cstc2021jcyj-msxmX0470","KJQN202100533"],"award-info":[{"award-number":["51707028","cstc2021jcyj-msxmX0470","KJQN202100533"]}]},{"name":"Chongqing Natural Science Foundation project","award":["51707028","cstc2021jcyj-msxmX0470","KJQN202100533"],"award-info":[{"award-number":["51707028","cstc2021jcyj-msxmX0470","KJQN202100533"]}]},{"name":"Science and Technology Funds of the Chongqing Municipal Education Commission","award":["51707028","cstc2021jcyj-msxmX0470","KJQN202100533"],"award-info":[{"award-number":["51707028","cstc2021jcyj-msxmX0470","KJQN202100533"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>In this study, an optimized unilateral magnetic resonance sensor with a three-magnet array is presented for assessing the aging of composite insulators in power grids. The sensor\u2019s optimization involved enhancing the static magnetic field strength and the homogeneity of the RF field while maintaining a constant gradient in the direction of the vertical sensor surface and maximizing homogeneity in the horizontal direction. The center layer of the target area was positioned 4 mm from the coil\u2019s upper surface, resulting in a magnetic field strength of 139.74 mT at the center point of the area, with a gradient of 2.318 T\/m and a corresponding hydrogen atomic nuclear magnetic resonance frequency of 5.95 MHz. The magnetic field uniformity over a 10 mm \u00d7 10 mm range on the plane was 0.75%. The sensor measured 120 mm \u00d7 130.5 mm \u00d7 76 mm and weighed 7.5 kg. Employing the optimized sensor, magnetic resonance assessment experiments were conducted on composite insulator samples utilizing the CPMG (Carr\u2013Purcell\u2013Meiboom\u2013Gill) pulse sequence. The T2 distribution provided visualizations of the T2 decay in insulator samples with different degrees of aging.<\/jats:p>","DOI":"10.3390\/s23125476","type":"journal-article","created":{"date-parts":[[2023,6,9]],"date-time":"2023-06-09T10:52:15Z","timestamp":1686307935000},"page":"5476","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Optimized Unilateral Magnetic Resonance Sensor with Constant Gradient and Its Applications in Composite Insulators"],"prefix":"10.3390","volume":"23","author":[{"given":"Pan","family":"Guo","sequence":"first","affiliation":[{"name":"College of Physics and Electronic Engineering, Chongqing Normal University, Chongqing 401331, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Chenjie","family":"Yang","sequence":"additional","affiliation":[{"name":"College of Physics and Electronic Engineering, Chongqing Normal University, Chongqing 401331, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jiamin","family":"Wu","sequence":"additional","affiliation":[{"name":"Shenzhen Academy of Aerospace Technology, Shenzhen 518057, China"},{"name":"School of Mechatronics Engineering, Harbin Institute of Technology, Harbin 150006, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3968-414X","authenticated-orcid":false,"given":"Zheng","family":"Xu","sequence":"additional","affiliation":[{"name":"School of Electrical Engineering, Chongqing University, Chongqing 400044, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,6,9]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"490","DOI":"10.1109\/TDEI.2016.006077","article-title":"Evaluation of Field-ageing Effects on Insulating Materials of Composite Suspension Insulators","volume":"24","author":"Mavrikakis","year":"2017","journal-title":"IEEE Trans. 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