{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,16]],"date-time":"2026-05-16T04:44:37Z","timestamp":1778906677972,"version":"3.51.4"},"reference-count":51,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2019,6,8]],"date-time":"2019-06-08T00:00:00Z","timestamp":1559952000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The dynamics of a hydrogen bonding network (HBN) relating to macroscopic properties of hydrogen bonding liquids were observed as a significant relaxation process by dielectric spectroscopy measurements. In the cases of water and water rich mixtures including biological systems, a GHz frequency relaxation process appearing at around 20 GHz with the relaxation time of 8.2 ps is generally observed at 25 \u00b0C. The GHz frequency process can be explained as a rate process of exchanges in hydrogen bond (HB) and the rate becomes higher with increasing HB density. In the present work, this study analyzed the GHz frequency process observed by suitable open-ended coaxial electrodes, and physical meanings of the fractal nature of water structures were clarified in various aqueous systems. Dynamic behaviors of HBN were characterized by a combination of the average relaxation time and the distribution of the relaxation time. This fractal analysis offered an available approach to both solution and dispersion systems with characterization of the aggregation or dispersion state of water molecules. In the case of polymer-water mixtures, the HBN and polymer networks penetrate each other, however, the HBN were segmented and isolated more by dispersed and aggregated particles in the case of dispersion systems. These HBN fragments were characterized by smaller values of the fractal dimension obtained from the fractal analysis. Some examples of actual usages suggest that the fractal analysis is now one of the most effective tools to understand the molecular mechanism of HBN in aqueous complex materials including biological systems.<\/jats:p>","DOI":"10.3390\/s19112606","type":"journal-article","created":{"date-parts":[[2019,6,10]],"date-time":"2019-06-10T03:16:51Z","timestamp":1560136611000},"page":"2606","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":14,"title":["Physical Meanings of Fractal Behaviors of Water in Aqueous and Biological Systems with Open-Ended Coaxial Electrodes"],"prefix":"10.3390","volume":"19","author":[{"given":"Shin","family":"Yagihara","sequence":"first","affiliation":[{"name":"Department of Physics, School of Science, Shonan Campus, Tokai University, Hiratsuka, Kanagawa 259-1292, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Rio","family":"Kita","sequence":"additional","affiliation":[{"name":"Department of Physics, School of Science, Shonan Campus, Tokai University, Hiratsuka, Kanagawa 259-1292, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0486-2911","authenticated-orcid":false,"given":"Naoki","family":"Shinyashiki","sequence":"additional","affiliation":[{"name":"Department of Physics, School of Science, Shonan Campus, Tokai University, Hiratsuka, Kanagawa 259-1292, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hironobu","family":"Saito","sequence":"additional","affiliation":[{"name":"Graduate School of Science and Technology, Shonan Campus, Tokai University, Hiratsuka, Kanagawa 259-1292, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yuko","family":"Maruyama","sequence":"additional","affiliation":[{"name":"Graduate School of Science and Technology, Shonan Campus, Tokai University, Hiratsuka, Kanagawa 259-1292, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tsubasa","family":"Kawaguchi","sequence":"additional","affiliation":[{"name":"Graduate School of Science and Technology, Shonan Campus, Tokai University, Hiratsuka, Kanagawa 259-1292, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kohei","family":"Shoji","sequence":"additional","affiliation":[{"name":"Course of Physics, Graduate School of Science, Shonan Campus, Tokai University, Hiratsuka, Kanagawa 259-1292, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tetsuya","family":"Saito","sequence":"additional","affiliation":[{"name":"Course of Physics, Graduate School of Science, Shonan Campus, Tokai University, Hiratsuka, Kanagawa 259-1292, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tsuyoshi","family":"Aoyama","sequence":"additional","affiliation":[{"name":"Course of Physics, Graduate School of Science, Shonan Campus, Tokai University, Hiratsuka, Kanagawa 259-1292, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ko","family":"Shimazaki","sequence":"additional","affiliation":[{"name":"Course of Physics, Graduate School of Science, Shonan Campus, Tokai University, Hiratsuka, Kanagawa 259-1292, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Keisuke","family":"Matsumoto","sequence":"additional","affiliation":[{"name":"Course of Physics, Graduate School of Science, Shonan Campus, Tokai University, Hiratsuka, Kanagawa 259-1292, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Minoru","family":"Fukuzaki","sequence":"additional","affiliation":[{"name":"Liberal Arts Education Center, Kumamoto Campus, Tokai University, Kumamoto 862-8652, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7200-4586","authenticated-orcid":false,"given":"Haruchika","family":"Masuda","sequence":"additional","affiliation":[{"name":"Department of Physiology, Division of Basic Medicine, Tokai University School of Medicine, Isehara Campus, Tokai University, Isehara, Kanagawa 259-1193, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Shinichiro","family":"Hiraiwa","sequence":"additional","affiliation":[{"name":"Department of Diagnostic Pathology, Tokai University Hachioji Hospital, Hachioji, Tokyo 192-0030, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Koji","family":"Asami","sequence":"additional","affiliation":[{"name":"Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Masayuki","family":"Tokita","sequence":"additional","affiliation":[{"name":"A Graduate School of Science, Kyushu University, 744, Motooka, Nishi-ku, Fukuoka 819-0395, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2019,6,8]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"024502","DOI":"10.1063\/1.4991850","article-title":"Dielectric and structural relaxation in water and some monohydric alcohols","volume":"147","author":"Kaatze","year":"2017","journal-title":"J. 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