{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,24]],"date-time":"2025-10-24T21:06:18Z","timestamp":1761339978153,"version":"build-2065373602"},"reference-count":41,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2019,5,26]],"date-time":"2019-05-26T00:00:00Z","timestamp":1558828800000},"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":["11404171"],"award-info":[{"award-number":["11404171"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Jiangsu Natural Science Foundation for Excellent Young Scholar","award":["BK20170101"],"award-info":[{"award-number":["BK20170101"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>We report a new method for detecting variable resistance during short time intervals by using an optical method. A novel variable-resistance sensor composed of up-conversion nanoparticles (NaYF4:Yb3+,Er3+) and reduced graphene oxide (RGO) is designed based on characteristics of a negative temperature coefficient (NTC) resistive element. The fluorescence intensity ratio (FIR) technology based on green and red emissions is used to detect variable resistance. Combining the Boltzmann distributing law with Steinhart\u2013Hart equation, the FIR and relative sensitivity SR as a function of resistance can be defined. The maximum value of SR is 1.039 \u00d7 10\u22123\/\u03a9. This work reports a new method for measuring variable resistance based on the experimental data from fluorescence spectrum.<\/jats:p>","DOI":"10.3390\/s19102400","type":"journal-article","created":{"date-parts":[[2019,5,26]],"date-time":"2019-05-26T23:07:27Z","timestamp":1558912047000},"page":"2400","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Detecting Variable Resistance by Fluorescence Intensity Ratio Technology"],"prefix":"10.3390","volume":"19","author":[{"given":"Wanjun","family":"Sheng","sequence":"first","affiliation":[{"name":"College of Electronic and Optical Engineering &amp; College of Microelectronics, Nanjing University of Posts and Telecommunications, Nanjing 210023, China"},{"name":"Key Laboratory of Radio Frequency and Micro-Nano Electronics of Jiangsu Province, Nanjing 210023, Jiangsu, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2365-3357","authenticated-orcid":false,"given":"Xiangfu","family":"Wang","sequence":"additional","affiliation":[{"name":"College of Electronic and Optical Engineering &amp; College of Microelectronics, Nanjing University of Posts and Telecommunications, Nanjing 210023, China"},{"name":"Key Laboratory of Radio Frequency and Micro-Nano Electronics of Jiangsu Province, Nanjing 210023, Jiangsu, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yong","family":"Tao","sequence":"additional","affiliation":[{"name":"Nanjing RZisources International Trading Co., Ltd., Nanjing 210019, Jiangsu, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xiaohong","family":"Yan","sequence":"additional","affiliation":[{"name":"College of Electronic and Optical Engineering &amp; College of Microelectronics, Nanjing University of Posts and Telecommunications, Nanjing 210023, China"},{"name":"Key Laboratory of Radio Frequency and Micro-Nano Electronics of Jiangsu Province, Nanjing 210023, Jiangsu, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2019,5,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"507","DOI":"10.1109\/TCT.1971.1083337","article-title":"Memristor-the missing circuit element","volume":"18","author":"Chua","year":"1971","journal-title":"IEEE Trans. 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