{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T03:39:21Z","timestamp":1760240361872,"version":"build-2065373602"},"reference-count":31,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2019,5,17]],"date-time":"2019-05-17T00:00:00Z","timestamp":1558051200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Basic Research Program of China (973 Program)","award":["2016YFF0200700"],"award-info":[{"award-number":["2016YFF0200700"]}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["61775045","61605030","61805054"],"award-info":[{"award-number":["61775045","61605030","61805054"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Shandong Provincial Natural Science Foundation of China","award":["ZR2016FM33"],"award-info":[{"award-number":["ZR2016FM33"]}]},{"name":"The 111 project to the Harbin Engineering University","award":["B13015"],"award-info":[{"award-number":["B13015"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>A regenerated fiber Bragg grating (RFBG) in silica fiber was used to observe the viscous relaxation process of the host silica fiber at high temperatures of around 1000 \u00b0C. Two factors, preannealing time and loaded tension, which affect viscous relaxation, were observed. When an RFBG is stretched after a longer preannealing, the measured viscosity of the optical fiber was observed to reach equilibrium faster, which means that preannealing accelerates viscous relaxation. A similar acceleration phenomenon was also observed when a larger load was applied to stretch the optical fiber, although the acceleration effect of loaded tension was not as strong as in the preannealing case. The results play an active role in establishing effective optical-fiber devices for application in high-temperature environments.<\/jats:p>","DOI":"10.3390\/s19102293","type":"journal-article","created":{"date-parts":[[2019,5,17]],"date-time":"2019-05-17T11:06:46Z","timestamp":1558091206000},"page":"2293","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Observing the Viscous Relaxation Process of Silica Optical Fiber at ~1000 \u00b0C Using Regenerated Fiber Bragg Grating"],"prefix":"10.3390","volume":"19","author":[{"given":"Zhiru","family":"Cui","sequence":"first","affiliation":[{"name":"Key Lab of In-Fiber Integrated Optics of Ministry of Education, Harbin Engineering University, Harbin 150001, China"}]},{"given":"Jianhui","family":"Gong","sequence":"additional","affiliation":[{"name":"Key Lab of In-Fiber Integrated Optics of Ministry of Education, Harbin Engineering University, Harbin 150001, China"}]},{"given":"Chen","family":"Wang","sequence":"additional","affiliation":[{"name":"Key Lab of In-Fiber Integrated Optics of Ministry of Education, Harbin Engineering University, Harbin 150001, China"}]},{"given":"Nana","family":"Che","sequence":"additional","affiliation":[{"name":"Key Lab of In-Fiber Integrated Optics of Ministry of Education, Harbin Engineering University, Harbin 150001, China"}]},{"given":"Yanshuang","family":"Zhao","sequence":"additional","affiliation":[{"name":"Key Lab of In-Fiber Integrated Optics of Ministry of Education, Harbin Engineering University, Harbin 150001, China"}]},{"given":"Quan","family":"Chai","sequence":"additional","affiliation":[{"name":"Key Lab of In-Fiber Integrated Optics of Ministry of Education, Harbin Engineering University, Harbin 150001, China"}]},{"given":"Haifeng","family":"Qi","sequence":"additional","affiliation":[{"name":"Laser Research Institute, Qilu University of Technology (Shandong Academy of Science), Jinan 250100, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4174-7090","authenticated-orcid":false,"given":"Elfed","family":"Lewis","sequence":"additional","affiliation":[{"name":"Key Lab of In-Fiber Integrated Optics of Ministry of Education, Harbin Engineering University, Harbin 150001, China"},{"name":"Optical Fiber Sensors Research Center, University of Limerick, V94 T9PX Limerick, Ireland"}]},{"given":"Jing","family":"Ren","sequence":"additional","affiliation":[{"name":"Key Lab of In-Fiber Integrated Optics of Ministry of Education, Harbin Engineering University, Harbin 150001, China"}]},{"given":"Jianzhong","family":"Zhang","sequence":"additional","affiliation":[{"name":"Key Lab of In-Fiber Integrated Optics of Ministry of Education, Harbin Engineering University, Harbin 150001, China"}]},{"given":"Jun","family":"Yang","sequence":"additional","affiliation":[{"name":"Key Lab of In-Fiber Integrated Optics of Ministry of Education, Harbin Engineering University, Harbin 150001, China"}]},{"given":"Libo","family":"Yuan","sequence":"additional","affiliation":[{"name":"Key Lab of In-Fiber Integrated Optics of Ministry of Education, Harbin Engineering University, Harbin 150001, China"}]},{"given":"Gang-Ding","family":"Peng","sequence":"additional","affiliation":[{"name":"Photonics and Optical Communications Group, School of Electrical Engineering, University of New South Wales, Sydney, NSW 2052, Australia"}]}],"member":"1968","published-online":{"date-parts":[[2019,5,17]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"7619","DOI":"10.1063\/1.1515132","article-title":"Viscosity of silica","volume":"92","author":"Doremus","year":"2002","journal-title":"J. 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