{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,12,6]],"date-time":"2025-12-06T04:45:30Z","timestamp":1764996330451,"version":"build-2065373602"},"reference-count":19,"publisher":"MDPI AG","issue":"23","license":[{"start":{"date-parts":[[2021,11,29]],"date-time":"2021-11-29T00:00:00Z","timestamp":1638144000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100005090","name":"Beijing Nova Program","doi-asserted-by":"publisher","award":["Z201100006820065"],"award-info":[{"award-number":["Z201100006820065"]}],"id":[{"id":"10.13039\/501100005090","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["No. 51876008"],"award-info":[{"award-number":["No. 51876008"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100004826","name":"Beijing Natural Science Foundation","doi-asserted-by":"publisher","award":["3202020)"],"award-info":[{"award-number":["3202020)"]}],"id":[{"id":"10.13039\/501100004826","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>A new freestanding sensor-based 3\u03c9 technique is presented here, which remarkably expands the application of traditional 3\u03c9 technology to anisotropic materials. The freestanding flexible sensor was fabricated using the mature flexible printed circuit production technique, which is non-destructive to the samples and applicable to porous surfaces. The thermal conductivities of potassium dihydrogen phosphate (KDP) crystal along the (100), (010) and (001) crystallographic planes were measured based on this new sensor at room temperature. We found that the freestanding flexible sensor has considerable application value for thermal properties\u2019 characterization for crystals with anisotropic thermophysical properties and other structures for which the traditional 3\u03c9 technique is not applicable.<\/jats:p>","DOI":"10.3390\/s21237968","type":"journal-article","created":{"date-parts":[[2021,12,1]],"date-time":"2021-12-01T01:45:02Z","timestamp":1638323102000},"page":"7968","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["Freestanding Flexible Sensor Based on 3\u03c9 Technique for Anisotropic Thermal Conductivity Measurement of Potassium Dihydrogen Phosphate Crystal"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3389-3741","authenticated-orcid":false,"given":"Lin","family":"Qiu","sequence":"first","affiliation":[{"name":"School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9899-6875","authenticated-orcid":false,"given":"Yuhao","family":"Ma","sequence":"additional","affiliation":[{"name":"School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yuxin","family":"Ouyang","sequence":"additional","affiliation":[{"name":"School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yanhui","family":"Feng","sequence":"additional","affiliation":[{"name":"School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xinxin","family":"Zhang","sequence":"additional","affiliation":[{"name":"School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,11,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"284","DOI":"10.1016\/j.optlastec.2018.10.001","article-title":"Effect of shock waves on thermophysical properties of ADP and KDP crystals","volume":"111","author":"Sivakumar","year":"2019","journal-title":"Opt. 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