{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,22]],"date-time":"2025-10-22T10:38:14Z","timestamp":1761129494484,"version":"build-2065373602"},"reference-count":37,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2017,10,13]],"date-time":"2017-10-13T00:00:00Z","timestamp":1507852800000},"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":["11574401"],"award-info":[{"award-number":["11574401"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Flow characteristics of water were tested in a rectangular microchannel for Reynolds number (Re) between 0 and 446 by terahertz time domain spectroscopy (THz-TDS). Output THz peak trough intensities and the calculated absorbances of the flow were analyzed theoretically. The results show a rapid change for Re &lt; 250 and a slow change as Re increases, which is caused by the early transition from laminar to transition flow beginning nearly at Re = 250. Then this finding is confirmed in the plot of the flow resistant. Our results demonstrate that the THz-TDS could be a valuable tool to monitor and character the flow performance in microscale structures.<\/jats:p>","DOI":"10.3390\/s17102330","type":"journal-article","created":{"date-parts":[[2017,10,13]],"date-time":"2017-10-13T11:34:09Z","timestamp":1507894449000},"page":"2330","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["The Detection of Water Flow in Rectangular Microchannels by Terahertz Time Domain Spectroscopy"],"prefix":"10.3390","volume":"17","author":[{"given":"Yan","family":"Song","sequence":"first","affiliation":[{"name":"State Key Laboratory of Petroleum Resources and Prospecting, China University of Petroleum, Beijing 102249, China"},{"name":"Beijing Key Laboratory of Optical Detection Technology for Oil and Gas, China University of Petroleum, Beijing 102249, China"}]},{"given":"Kun","family":"Zhao","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Petroleum Resources and Prospecting, China University of Petroleum, Beijing 102249, China"},{"name":"Beijing Key Laboratory of Optical Detection Technology for Oil and Gas, China University of Petroleum, Beijing 102249, China"}]},{"given":"Jian","family":"Zuo","sequence":"additional","affiliation":[{"name":"Department of Physics, Key Laboratory of Terahertz Optoelectronics, Ministry of Education, Capital Normal University, Beijing 100048, China"}]},{"given":"Cuicui","family":"Wang","sequence":"additional","affiliation":[{"name":"Department of Physics, Key Laboratory of Terahertz Optoelectronics, Ministry of Education, Capital Normal University, Beijing 100048, China"}]},{"given":"Yizhang","family":"Li","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Petroleum Resources and Prospecting, China University of Petroleum, Beijing 102249, China"},{"name":"Beijing Key Laboratory of Optical Detection Technology for Oil and Gas, China University of Petroleum, Beijing 102249, China"}]},{"given":"Xinyang","family":"Miao","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Petroleum Resources and Prospecting, China University of Petroleum, Beijing 102249, China"},{"name":"Beijing Key Laboratory of Optical Detection Technology for Oil and Gas, China University of Petroleum, Beijing 102249, China"}]},{"given":"Xiaojing","family":"Zhao","sequence":"additional","affiliation":[{"name":"Department of Physics, Key Laboratory of Terahertz Optoelectronics, Ministry of Education, Capital Normal University, Beijing 100048, China"}]}],"member":"1968","published-online":{"date-parts":[[2017,10,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"977","DOI":"10.1103\/RevModPhys.77.977","article-title":"Microfluidics: Fluid physics at the nanoliter scale","volume":"77","author":"Squires","year":"2015","journal-title":"Rev. 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