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1. Physical Meanings of Fractal Behaviors of Water in Aqueous and Biological Systems with Open-Ended Coaxial Electrodes

Author

Shin Yagihara, Rio Kita, Naoki Shinyashiki, Hironobu Saito, Yuko Maruyama, Tsubasa Kawaguchi, Kohei Shoji, Tetsuya Saito, Tsuyoshi Aoyama, Ko Shimazaki, Keisuke Matsumoto, Minoru Fukuzaki, Haruchika Masuda, Shinichiro Hiraiwa, Koji Asami, and Masayuki Tokita

Subjects
dielectric spectroscopy, aqueous mixtures, open-ended coaxial electrodes, water structures, fractal concept, Chemical technology, TP1-1185
Abstract

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 °C. 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.

Published
2019
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2. Physical Meanings of Fractal Behaviors of Water in Aqueous and Biological Systems with Open-Ended Coaxial Electrodes

Author

Tsubasa Kawaguchi, Shin Yagihara, Masayuki Tokita, Shinichiro Hiraiwa, Hironobu Saito, Ko Shimazaki, Keisuke Matsumoto, Kohei Shoji, Tetsuya Saito, Koji Asami, Rio Kita, Haruchika Masuda, Minoru Fukuzaki, Naoki Shinyashiki, Tsuyoshi Aoyama, and Yuko Maruyama

Subjects
Materials science, open-ended coaxial electrodes, 02 engineering and technology, 010402 general chemistry, lcsh:Chemical technology, 01 natural sciences, Biochemistry, Fractal dimension, Article, Analytical Chemistry, Fractal, aqueous mixtures, lcsh:TP1-1185, Electrical and Electronic Engineering, Instrumentation, Electrodes, chemistry.chemical_classification, water structures, Aqueous solution, Water, Polymer, 021001 nanoscience & nanotechnology, Fractal analysis, Atomic and Molecular Physics, and Optics, 0104 chemical sciences, Dielectric spectroscopy, Characterization (materials science), fractal concept, chemistry, Chemical physics, Dielectric Spectroscopy, 0210 nano-technology, Dispersion (chemistry)
Abstract

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 &deg, C. 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.

Published
2019

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