Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1021/acsomega.2c00677

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Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1021/acs.langmuir.1c01339

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1021/acs.langmuir.1c00041

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.2494/photopolymer.33.599

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.2494/photopolymer.33.603

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Publishing type：Research paper (scientific journal)   Publisher：Technical Association of Photopolymers, Japan  

DOI： 10.2494/photopolymer.33.205

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1021/acsomega.9b04184

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.2494/photopolymer.33.185

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Publisher：Springer Singapore  

DOI： 10.1007/978-981-15-5451-3_24

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1021/acs.langmuir.9b03356

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.2494/photopolymer.32.279

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1021/acs.langmuir.9b02358

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Language：English   Publishing type：Research paper (international conference proceedings)  

DOI： 10.1038/s42004-019-0192-6

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Language：English   Publishing type：Research paper (scientific journal)  

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1038/s41428-019-0192-5

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1021/acs.langmuir

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1021/acs.macrmol.8b02426

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1021/acs.langmuir.8b02251

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1002/chem.201705427/full

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1021/acsami.7b11375

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1039/c7py00158d

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1021/acsami.7b00806

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1063/1.4979883

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：JAPAN OIL CHEMISTS SOC  

Hierarchical structures, also known as fractal structures, exhibit advantageous material properties, such as water- and oil-repellency as well as other useful optical characteristics, owing to its self similarity. Various methods have been developed for producing hierarchical geometrical structures. Recently, fractal structures have been manufactured using a 3D printing technique that involves computer aided design data. In this study, we confirmed the accuracy of geometrical structures when Koch curve-like fractal structures with zero to three generations were printed using a 3D printer. The fractal dimension was analyzed using a box-counting method. This analysis indicated that the fractal dimension of the third generation hierarchical structure was approximately the same as that of the ideal Koch curve. These findings demonstrate that the design and production of fractal structures can be controlled using a 3D printer. Although the interior angle deviated from the ideal value, the side length could be precisely controlled.

DOI： 10.5650/jos.ess16151

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

We evaluated the frictional properties of emulsions on fractal agar gel substrates. The friction force and its temporal profile depend on the ternary mixed state. An unstable emulsion containing a large amount of oil shows a significant lubricating effect.

DOI： 10.1246/cl.160893

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DOI： 10.5650/jos.ess16085

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1021/jacs.6b05562

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

Understanding the dynamics with which a water droplet penetrates a pore is important because of its relationship with transfer phenomena in plants and animals. Using a high-speed camera, we observe the penetration processes of a water droplet into a cylindrical pore on a silicone substrate. The force on the water droplet is generated by dropping the substrate plus water droplet from a height of several centimeters onto an acrylic resin substrate. The penetration characteristics depend on pore size D-p, height of release of a drop h, and the viscosity of the droplet liquid and are classified into the following patterns: spreading, penetration, and breaking. During the process of relaxation to the steady state, various interesting deformation or oscillation phenomena occur. Based on high-speed images, interfacial energy Delta G during the intermediate states and find an energy barrier Delta G = 1 X 10(-7) J when D-p = 1.0 we estimate the mm and h = 15 based on a theoretical model considering the driving and suppression factors, we explain the experimentally obtained phase diagram including the separation, penetration, and breaking patterns.

DOI： 10.1021/acs.langmuir.6b01509

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Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

ポリピロール微粒子を安定化剤として用いたリキッドマーブル（安定化剤が液滴表面を覆って水面に浮かぶ液滴）を光で駆動して運搬し、内部の物質を放出する技術を確立した。さらに駆動力の大きさを評価した。

DOI： 10.1002/adfm.201600034

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1039/c6cc01638c

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.15761/AMS.1000105

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Language：Japanese   Publisher：The Physical Society of Japan (JPS)  

DOI： 10.11316/jpsgaiyo.71.1.0_3220

CiNii Books

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：NATURE PUBLISHING GROUP  

We have demonstrated compression stress induced mechanical deformation of microtubules (MTs) on a two-dimensional elastic medium and investigated the role of compression strain, strain rate, and a MT-associated protein in the deformation of MTs. We show that MTs, supported on a two-dimensional substrate by a MT-associated protein kinesin, undergo buckling when they are subjected to compression stress. Compression strain strongly affects the extent of buckling, although compression rate has no substantial effect on the buckling of MTs. Most importantly, the density of kinesin is found to play the key role in determining the buckling mode of MTs. We have made a comparison between our experimental results and the 'elastic foundation model' that theoretically predicts the buckling behavior of MTs and its connection to MT-associated proteins. Taking into consideration the role of kinesin in altering the mechanical property of MTs, we are able to explain the buckling behavior of MTs by the elastic foundation model. This work will help understand the buckling mechanism of MTs and its connection to MT-associated proteins or surrounding medium, and consequently will aid in obtaining a meticulous scenario of the compression stress induced deformation of MTs in cells.

DOI： 10.1038/srep17222

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1021/acs.langmuir.5b00670

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1038/pj.2015.29

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1017/S0025315415000119

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DOI： 10.1246/cl.150005

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Language：Japanese   Publisher：The Physical Society of Japan (JPS)  

DOI： 10.11316/jpsgaiyo.70.1.0_3389

CiNii Books

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Language：Japanese   Publisher：The Physical Society of Japan (JPS)  

DOI： 10.11316/jpsgaiyo.70.2.0_2890

CiNii Books

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

The effects of silica particle addition on the wetting velocity on flat and fractal agar gel surfaces were analyzed along with the applicability of such particles for controlling the wetting dynamics of water. The contact angles (theta(D)) of the colloidal dispersions obeyed the power law, i.e., theta(D) proportional to t(-x), where t is time and xis a constant. Wetting was inhibited by the addition of a suitable amount of 20-nm-diameter silica particles. Specifically, the exponent x reached a minimum value for a silica composition of 0.1 wt%. However, such inhibition effects were not observed upon the addition of silica particles with diameters of 100, 550, and, 1000 nm. The mechanism of the inhibition of the liquid wetting on gel surfaces may be attributed to a slight increase in local viscosity around the contact line during wetting. (C) 2014 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.colsurfb.2014.06.031

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1021/la502565j

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

The microtubule (MT) is the stiffest cytoskeletal filamentous protein that takes part in a wide range of cellular activities where its mechanical property plays a crucially significant role. How a single biological entity plays multiple roles in cell has been a mystery for long time. Over the recent years, it has been known that modulation of the mechanical property of MT by different cellular agents is the key to performing manifold in vivo activities by MT. Studying the mechanical property of MT thus has been a prerequisite in understanding how MT plays such diversified in vivo roles. However, the anisotropic structure of MT has been an impediment in obtaining a precise description of the mechanical property of MT along its longitudinal and lateral directions that requires employment of distinct experimental approach and has not been demonstrated yet. In this work, we have developed an experimental system that enabled us to investigate the effect of tensile stress on MT. By using our newly developed system, (1) we have determined the Young's modulus of MT considering its deformation under applied tensile stress and (2) a new role of MT associated motor protein kinesin in modulating the mechanical property of MT was revealed for the first time. Decrease in Young's modulus of MT with the increase in interaction with kinesin suggests that kinesin has a softening effect on MT and thereby can modulate the rigidity of MT. This work will be an aid in understanding the modulation of mechanical property of MTs by MT associated proteins and might also help obtain a clear insight of the endurance and mechanical instability of MTs under applied stress.

DOI： 10.1021/bm5001789

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Language：English   Publishing type：Research paper (scientific journal)  

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1021/jp412806y

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Language：English   Publishing type：Research paper (scientific journal)  

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Language：English   Publishing type：Research paper (scientific journal)  

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Language：Japanese   Publishing type：Research paper (scientific journal)  

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1021/jp500824e

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Language：English   Publisher：The Biophysical Society of Japan General Incorporated Association  

DOI： 10.2142/biophys.54.S269_6

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Language：English   Publisher：The Biophysical Society of Japan General Incorporated Association  

DOI： 10.2142/biophys.54.S269_5

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1140/epjb/e2013-40353-3

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1021/la4014834

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DOI： 10.1246/cl.130307

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DOI： 10.5650/jos.62.587

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Language：English   Publishing type：Research paper (scientific journal)  

The proceeding of The XIII International Conference on the Physics of Non-Crystalline Solids

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Language：English   Publisher：The Biophysical Society of Japan General Incorporated Association  

DOI： 10.2142/biophys.53.S232_1

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1021/jp408417h

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ROYAL SOC CHEMISTRY  

The microtubule (MT)-kinesin system is a promising candidate for constructing artificial biomachines. The active self-organisation (AcSO) method has been developed to integrate MT filaments into highly organised assembled structures. The creation of ring-shaped MT assemblies is one of the outcomes of the organisation process and holds prospects for use in future nano-technological applications. However, making use of ring-shaped MT assemblies in practical applications requires further control of the size of these assemblies, which has not yet been addressed. In this work, we demonstrated AcSO of MTs in a stepwise manner inside an inert atmosphere. We show that in an inert atmosphere, AcSO could be performed several times (at least nine times), and as a result, this method successfully increased the thickness of ring-shaped MT assemblies.

DOI： 10.1039/c3sm50704a

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Language：English   Publishing type：Research paper (scientific journal)  

The proceeding of The XIII International Conference on the Physics of Non-Crystalline Solids

DOI： 10.1016/j.phpro.2013.07.018

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Language：English   Publishing type：Research paper (scientific journal)  

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1021/la3043846

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

We successfully determined the three-dimensional structure of agar gel droplets on multipillared surfaces. The contact angle, length of penetration of the agar gel into the interspace between pillars, and curvature of the bottom surface of the droplets were changed with respect to changes in the volume and concentration of the aqueous agar solution and the distance between the surface-bound pillars.

DOI： 10.1246/cl.2012.960

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1039/c2sm26441b

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：JAPAN OIL CHEMISTS SOC  

Liquid marbles are water droplets covered with solid particles. Here we show a method for the preparation of edible liquid marbles and capsules covered with fatty acid crystals and triacylglycerol crystals. We prepared liquid marbles using a simple method; namely, a water droplet was rolled on lipid crystals in petri dishes. The resulting marbles were converted to capsules covered with a lipid shell by heating. These marbles were stable not only on glass surfaces but also on water surfaces because they had rigid hydrophobic exteriors. The lifetime of the liquid marbles on water depended on the alkyl chain length of the lipid molecules and the pH of the water. These findings are useful for applying liquid marbles to food, cosmetic, and medical products.

DOI： 10.5650/jos.61.477

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

We have experimentally observed anomalous spreading of aqueous alcohol solutions on flat and rough fractal agar gel surfaces. On flat agar gel surfaces, extremely fast spreading [theta(D)(t) proportional to t(-0.92)] that differs from Tanner's law [theta(D)(t) proportional to t(-0.3)] was observed when the liquid contained over 9 wt % of 1-propanol in which strong Marangoni flow was observed as a fluctuation on the liquid surface. However, on fractal gel surfaces, different spreading dynamics [theta(D)(t) proportional to t(-0.58)] were observed, although Marangoni flow still occurred. We found the surface-dependent spreading can be discussed in terms of competition between Marangoni flow and the pinning effect due to surface roughness.

DOI： 10.1021/la2049597

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Language：English   Publishing type：Research paper (scientific journal)  

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1002/asia.201100218

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DOI： 10.1021/la2006524

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ROYAL SOC CHEMISTRY  

In this study, we show that the energy-dissipative active self-assembly of microtubules (MTs) via a kinesin-based motility system produces various MT assemblies such as bundle-, network-, and ring-shaped structures depending on the initial conditions. Structural polymorphism of the MT assembly is depicted through phase diagrams, and morphogenesis of the MT assembly is discussed based on the following factors: binding force between MTs and motility-driving force from kinesins. This study provides new insights into the energy-dissipative dynamic self-organization of biological systems.

DOI： 10.1039/c1sm05413a

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Language：English   Publishing type：Research paper (scientific journal)  

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Language：English   Publishing type：Research paper (scientific journal)  

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DOI： 10.1103/PhysRevE.70.021910

Scopus

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Other Link： http://orcid.org/0000-0002-2751-7136

DOI： 10.1016/j.cplett.2004.08.061

Scopus

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Other Link： http://orcid.org/0000-0002-2751-7136

DOI： 10.1016/S0960-0779(02)00382-X

Scopus

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Other Link： http://orcid.org/0000-0002-2751-7136

Language：Japanese   Publisher：The Society of Polymer Science, Japan  

DOI： 10.1295/kobunshi.51.936

CiNii Books

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Other Link： https://jlc.jst.go.jp/DN/JALC/00160683419?from=CiNii

Language：Japanese   Publisher：The Institute of Electrical Engineers of Japan  

DOI： 10.1541/ieejjournal.121.238

CiNii Books

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Other Link： https://jlc.jst.go.jp/DN/JALC/00072446898?from=CiNii

Scopus

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Other Link： http://orcid.org/0000-0002-2751-7136

DOI： 10.1016/S0009-2614(00)01076-9

Scopus

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Other Link： http://orcid.org/0000-0002-2751-7136

DOI： 10.1016/S0009-2614(00)00004-X

Scopus

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Other Link： http://orcid.org/0000-0002-2751-7136

DOI： 10.1002/1521-3900(200010)160:1<55::AID-MASY55>3.0.CO;2-T

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Other Link： http://orcid.org/0000-0002-2751-7136

Authorship：Lead author   Language：Japanese   Publishing type：Article, review, commentary, editorial, etc. (trade magazine, newspaper, online media)   Publisher：ニューサイエンス社  

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Authorship：Lead author   Language：Japanese   Publishing type：Article, review, commentary, editorial, etc. (trade magazine, newspaper, online media)   Publisher：ニューサイエンス社  

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Language：Japanese  

J-GLOBAL

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Language：English   Publisher：AMER CHEMICAL SOC  

Wetting on a cylindrical pillar defect is discussed in terms of the free-energy difference Delta G. Wetting is divided into wetting on a flat surface, a pinning effect at the apex of the defect, and wetting on a pillar wall. First, we confirmed that Delta G between before and after ideal wetting on a flat surface can be derived as a function of the contact angle theta in which the free-energy minimum is obtained as the equilibrium contact angle theta(eq) described by Young's and Wenzel's laws. Second, the pinning effect at the apex in the cross section of the pillar defect is discussed in Delta G, where the pinning effect is shown to originate from the energy barrier by an increase in the air-liquid interfacial area of a pinned droplet induced by deformation. Next, the Delta G profiles of wetting on the pillar wall are drawn based on the theory of Carroll (Carroll, B. J. J. Colloid Interface Sci. 1976, 57, 488-495) to better understand the Delta G profile during penetration. Differences in the manner of wetting between the wetting state on a flat surface and the pillar wall are reflected in Delta G. Finally, penetration of a droplet into a pillar defect is comprehensively discussed on the basis of wetting on a flat surface and a pillar wall. If we consider a simple manner of penetration, another type of energy barrier resulting from an anomalous deformation of the air-liquid interface of the penetrating droplet can be theoretically suggested. Consequently, two types of energy barrier are found. These energy barriers should play a significant role in the hysteresis of wetting, the liquid-repellent Cassie-Baxter state (CB), and the CB-Wenzel wetting transition on a microtextured surface.

DOI： 10.1021/la104600x

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Language：English   Publisher：AMER CHEMICAL SOC  

Agar gels with hierarchical rough surfaces, referred to as "fractal agar gels," were prepared to model biological surfaces coated with mucus. Agar gels with rough surfaces of fractal dimension D = 2.2 were synthesized by transferring a fractal surface structure of alkylketene dimer (AKD). The rough structure accelerated the spreading of water droplets and induced the appearance of a wicking front. The mechanism of acceleration of the spreading on fractal surfaces based on a semiquantitative theoretical model was also clarified.

DOI： 10.1021/la103123d

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Language：English   Publisher：AMER CHEMICAL SOC  

Phase behavior of CO2 confined in porous fractal silica with volume fraction of SiO2 phi(s) = 0.15 was investigated using small-angle neutron scattering (SANS) and ultrasmall-angle neutron scattering (USANS) techniques. The range of fluid densities (0 &lt; (rho(CO2))(bulk) &lt; 0.977 g/cm(3)) and temperatures (T = 22 degrees C, 35 and 60 degrees C) corresponded to gaseous, liquid, near critical and supercritical conditions of the bulk fluid. The results revealed formation of a dense adsorbed phase in small pores with sizes D &lt; 40 angstrom at all temperatures. At low pressure (P &lt; 55 bar, (rho(CO2))(bulk) &lt; 0.2 g/cm(3)) the average fluid density in pores may exceed the density of bulk fluid by a factor up to 6.5 at T = 22 degrees C. This "enrichment factor" gradually decreases with temperature, however significant fluid densification in small pores still exists at temperature T = 60 degrees C, i.e., far above the liquid gas critical temperature of bulk CO2 (T-C = 31.1 degrees C). Larger pores are only partially filled with liquid-like adsorbed layer which coexists with unadsorbed fluid in the pore core. With increasing pressure, all pores become uniformly filled with the fluid, showing no measurable enrichment or depletion of the porous matrix with CO2.

DOI： 10.1021/la904032p

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Language：English   Publisher：ELSEVIER SCIENCE BV  

Super water- and highly oil-repellent films have been synthesized by electrochemical polymerization of some new monomers of fluorinated alkylpyrroles. The surface roughness of the films was controlled by the polymerization conditions such as concentration of monomers, applied voltages, polymerization time and so on. The contact angles on the most liquid-repellent film surfaces are about 160 degrees and 140 degrees for water and salad oil, respectively. The sliding angle for the salad oil is 9.5 +/- 2.5 degrees which is much better than that on the poly(alkylpyrrole) films coated with a fluorinated aikylsilane coupling agent. Thermal and organic solvent stability for the liquid-repellent property of the films were quite good to be used practically. (C) 2009 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.colsurfa.2009.09.029

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Language：English   Publisher：WILEY-V C H VERLAG GMBH  

DOI： 10.1002/anie.201000793

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Authorship：Lead author   Language：Japanese   Publishing type：Article, review, commentary, editorial, etc. (trade magazine, newspaper, online media)   Publisher：工業調査会  

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Language：English   Publisher：ELSEVIER SCIENCE BV  

Curie temperature T-C of spin arrangement with arbitrary dimension was considered. We assumed that interaction of a spin with all other spins vary with a power-law decay rate in exchange integral on Heisenberg model. As a result, we found that T-C, which was obtained from T-C = lambda C (lambda: mean-field coefficient and C: Curie constant), significantly depends on fractal dimension of spin arrangements D, the exchange integral and the decay constant. This semi-quantitatively explains how T-C depends on D (1 &lt;= D &lt;= 3) in a universal way and also the finite size effect on T-C in low-dimensional spin systems. Crown Copyright (C) 2009 Published by Elsevier B.V. All rights reserved.

DOI： 10.1016/j.physe.2009.08.013

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Language：English   Publisher：ACADEMIC PRESS INC ELSEVIER SCIENCE  

We have succeeded in creating Menger sponge-like fractal body, i.e., porous-silica samples with Menger sponge-like fractal geometries, by a novel template method utilizing template particles of alkylketene dimer (AKD) and a sol-gel synthesis of tetramethyl orthosilicate (TMOS). We report here the first experimental results on characterization and structural investigations of the fractal porous-silica samples prepared with various conditions such as calcination temperature and packing condition of the template particles. in order to characterize the fractal porous-silica samples, pore volume distribution, porosity and specific Surface area were measured over an extremely wide scale from*1 nm to 100 mu m by means of Mercury porosimetry, (1)H NMR cryoporometry, nitrogen gas adsorption experiments together with direct evaluations of cross-sectional fractal dimension D(cs), and size limits of D(cs). We have found that the pore volume distribution and specific surface area of the fractal porous-silica samples can be discussed in terms of different fractal porous Structures at different scale regions. Crown Copyright (C) 2009 Published by Elsevier Inc. All rights reserved.

DOI： 10.1016/j.jcis.2009.03.087

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Language：English   Publisher：ROYAL SOC CHEMISTRY  

"Blooming" of tristearin (SSS), a spontaneous formation of flake-like surface structure on a triacylglycerol (TAG), is discussed. It has been well known that blooming of TAGs was closely related to the polymorphism, however, a foundamental question on how the blooming on the micrometre scale was connected with the polymorphism on the molecular scale is still unclear. We first found that the flakes were formed to release deformation energy of the surface, induced by phase transformation from the alpha-phase to the beta&apos;-phase in the polymorphism of SSS. It was also able to explain the flake size observed in experiments (similar to 3 mu m x 3 mu m x 0.1 mu m). This theory would provide a better understanding of the spontaneous formation of surface structures in chocolate, fats, fatty acids, waxes, and water-repellent leaves of grasses.

DOI： 10.1039/b815005b

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Language：English   Publisher：AMER CHEMICAL SOC  

Alkylketene dimers (AKDs) and triglyceride waxes form fractal surfaces spontaneously and show super water-repellent property. Spontaneous formation of fractal structures on their surfaces takes place when the meta-stable crystalline phase of the waxes transforms to the thermodynamically stable form of crystal. The triglyceride waxes form the meta-stable alpha-phase in whole specimen when solidified from their melt. In the case of AKD, on the other hand, only a small portion of the specimen solidifies in the meta-stable form of crystal. The surface of the AKD, however, becomes fractal in the whole part. We have, thus, examined the fractal structure formation in the mixed wax systems in which one wax forms fractal surfaces and the other one does not. In the stearic acid/tristearin mixed system as a typical one, the super water-repel tent fractal surfaces form in the higher composition region of tristearin than that of the eutectic point in their mixture.

DOI： 10.1021/jp802268j

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Language：English   Publisher：JAPAN SOCIETY APPLIED PHYSICS  

Photochrronic diarylethene forms super water-repellent surfaces upon irradiation with UV light. Microfibril-like crystals grow on the solid diarylethene surface after UV irradiation, and the contact angle of water on the surface becomes larger with increasing surface roughness with time. The fractal analysis was made by box-counting method for the rough surfaces. There are three regions in the roughness size having the fractal dimension of ca. 2.4 (size of roughness smaller than 5 mu m), of ca. 2.2 (size of roughness between 5-40 mu m). and of ca. 2.0 (size of roughness larger than 40 mu m). The fractal dimension of ca. 2.4 was due to the fibril-like structures generated by UV irradiation on diarylethene surfaces accompanied with an increase in the contact angle. The surface structure with larger fractal dimension mainly contributes to realizing the super water-repellency of the diarylethene surfaces. This mechanism of spontaneous formation of fractal surfaces is similar to that for triglyceride and alkylketene dimer waxes.

DOI： 10.1143/JJAP.47.7298

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Language：English   Publisher：SPRINGER  

The unique structure of a set of self-assembled porous silica materials was characterized through a combined small-angle scattering (CSAS) method using small- and ultra-small angle neutron scattering as well as small-angle X-ray scattering. The porous silica specimens investigated were prepared by a sol-gel method under the presence of alkylketene dimer (AKD) template particles and through calcination, which leads to the development of porous silica having a mass-fractal structure over length scales from similar to 100 nm to similar to 10 mu m. Furthermore, the specimens posses a hierarchical structure, which consist of a fractal porous structure, and also contain primary silica particles less than 10 nm in size, which form a continuous silica matrix. To characterize these complex structures, observation over a broad range of length scales is indispensable. We propose a CSAS technique that serves this purpose well.

DOI： 10.1140/epjb/e2008-00223-9

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Language：English   Publisher：ELSEVIER SCIENCE BV  

Alkylketene dimer (AKD), a kind of wax, has been known to form fractal surfaces spontaneously, and to show super water-repellent property. In order to understand further the super water-repellency of the AKD surfaces and to elucidate the mechanism of spontaneous formation of the fractal structures on the wax surfaces, a pure and a mixed AKD samples were employed to make the surfaces by the melt-solidification method. Time-dependent contact angles of water droplets on the AKD surfaces cured at several temperatures were systematically measured. It was found that spontaneous formation of super water-repellent surfaces was thermally induced quite effectively. For example, it took about 6 days for the pure AKD surface to show the super water-repellency at 40 degrees C but did just 1 h at 50 degrees C. The fractal dimension of the mixed AKD surface with super water-repellency was calculated to be 2.26 from the SEM images by the box-counting method which should be reasonably compared with 2.29 of pure AKD surface. The mechanism for the spontaneous formation of fractal structures was discussed from the results of the time-dependent contact angles, differential scanning calorimetric (DSC) curves and X-ray diffractometric (XRD) patterns. It has been made clear that the fractal AKD surface and its super water-repellency result from the phase transformation from the metastable state to the stable one of the AKD crystals. (c) 2007 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.colsurfa.2007.09.010

Web of Science

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Language：Japanese  

J-GLOBAL

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Language：English   Publisher：ROYAL SOC CHEMISTRY  

Alkylketene dimer (AKD: a kind of wax) spontaneously forms a fractal structure and its surfaces show super water-repellency (the contact angle = 174 degrees). However, the formation mechanism of the fractal surfaces of AKD is still unclear. In this work, surface structures, wettability and phase behaviors of various waxes have been investigated in order to understand the mechanism for spontaneous formation of super water-repellent fractal surfaces. We have found an empirical general rule without any exceptions at least for the wax samples tested. First, the wax must form a meta-stable crystalline phase when solidified from its melt. Then, the super water-repellent fractal surfaces form spontaneously during the phase transition from a meta-stable to a stable crystalline form. The tempering method also supported the above rule for the waxes showing the fractal structure formation on their surfaces.

DOI： 10.1039/b712938f

Web of Science

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Language：English   Publisher：ACADEMIC PRESS INC ELSEVIER SCIENCE  

We present electrochemical synthesis of super water-repellent poly(alkylpyrrole) films which exhibit excellent environmental stability in terms of contact angle (&gt; 150 degrees) for water. The poly(alkylpyrrole) films synthesized under an optimized electrochemical condition consisted of thousands of micro-scaled 'needles' which densely aligned by shoulder to shoulder. The surface of the aligned 'needles' was analyzed by a box-counting method, to be a fractal structure with a dimension of 2.18. (c) 2006 Elsevier Inc. All rights reserved.

DOI： 10.1016/j.jcis.2006.07.052

Web of Science

PubMed

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Language：English   Publisher：AMER INST PHYSICS  

Volume phase transitions of a DNA gel and a single giant DNA chain caused by spermidine(3+) (SPD3+) were investigated. The change in volume for the single DNA (V/V-0 similar to 10(-5)) was four orders of magnitude greater than that for the DNA gel (similar to 10(-1)), while the critical SPD3+ concentration for the gel (1.8 mM) was one order of magnitude greater than that of the single DNA (0.12-0.25 mM) at the same pH 6.86. We tried to describe mean-field theories with virial expansion, which is valid for the coil-globule transition of a single polymer chain, for the volume phase transitions to explain the reason why such marked differences appeared. Considering the degree of the ordering of Kuhn segments arising from the gel network structure together with the chain length of cross-linked polymer chains, the volume phase transitions were described and then the significant differences were reproduced quantitatively. We concluded that the network structure plays a significant role in the volume phase transition of the gel. (C) 2007 American Institute of Physics.

DOI： 10.1063/1.2748767

Web of Science

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Language：English   Publisher：AMER CHEMICAL SOC  

Alkylketene dimer (AKD), a kind of wax, has been known to form fractal surfaces spontaneously and show super water-repellency. Such formation of water-repellent and fractal surfaces was also found in this work for triglycerides. Since the crystal phase transitions of these waxes were well studied, we studied the formation of their fractal surfaces through contact angle measurements, differential scanning calorimetry (DSC), and X-ray diffraction (XRD). From time-dependent contact angle measurements, it was found that the formation of super water-repellent surfaces with fractal structures occurred spontaneously also on the triglyceride surfaces at different temperatures. The freshly solidified triglyceride surfaces were almost transparent, and their initial contact angles of water were close to 110 degrees. The surfaces then became rough and clouded after being incubated for a certain time at a specified temperature. The super water-repellent surfaces were quite rough and showed fractal structures with the dimension of ca. 2.2 calculated from the scanning electron microscopic (SEM) images by the box-counting method. The phase transformation from a metastable state to a stable cystalline one after the solidification from the melt of triglycerides was clearly observed by DSC and XRD measurements. The fractal crystalline structures and the super water-repellency resulted from this phase transformation and the crystal growth. Ensuring the initial sample solidified into the metastable state and curing the surface at an appropriate temperature are key factors for the successful preparation of fractal triglyceride surfaces by the solidification method.

DOI： 10.1021/jp065589o

Web of Science

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Language：English   Publisher：ACADEMIC PRESS INC ELSEVIER SCIENCE  

A nonionic surfactant, n-dodecyl glyceryl itaconate (DGI), self-assembles into bilayer membranes in water having a spacing distance of submicrometer in the presence of small amounts of ionic surfactants, and shows beautiful iridescent color. Ionic surfactants have strong effects on this iridescent system. We have interestingly found that the iridescent color changes with time after mixing DGI and ionic surfactants and the color in equilibrium state changes greatly with concentration of the ionic surfactants. The time-dependent color change results from the transformation of DGI aggregate structure after being mixed with ionic surfactant. It is first found that the iridescent color of this nonionic system can be changed from red to deep blue by altering the concentration of ionic surfactants added even though the total concentration of surfactant is almost constant. Such large blue shift of the iridescent color in equilibrium state cannot be fully explained by the ordinary undulation theory applied so far for this phenomenon. The flat lamellar sheets tend to curve by increasing the concentration of ionic surfactants to form separated onion-like and/or myelin-like structures. These separated structures of lamellar system result in the decrease of spacing distance between bilayer membranes because some vacant spaces necessarily appear among these structures. (c) 2006 Elsevier Inc. All rights reserved.

DOI： 10.1016/j.jcis.2006.09.070

Web of Science

PubMed

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Language：English   Publisher：AMER INST PHYSICS  

We have established experimental strategies on how to create a Menger sponge-like fractal body and how to control its fractal dimension. The essence was to utilize alkylketene dimer (AKD), which spontaneously forms super-water-repellent fractal surface. We prepared "fractal AKD particles" with fractal surface structure as templates of pores in fractal body. The fractal body was synthesized by filling the remained space between the packed template particles with a tetramethyl orthosilicate solution, solidifying it by the sol-gel process, and removing the template by calcinations. We have succeeded in systematically creating fractal bodies of silica with different cross-sectional fractal dimensions D-cs=1.87, 1.84, and 1.80 using "fractal template particles" compressed under the ratio=1.0, 2.0, and 3.0, respectively. We also discussed the possibilities of their fractal geometries in comparison with mathematical models. We concluded that the created fractal bodies were close to a Menger sponge and its modified one. Our experimental strategy allows us to design fractality of porous materials. (c) 2006 American Institute of Physics.

DOI： 10.1063/1.2336200

Web of Science

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Event date： 2021.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン  

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Event date： 2021.6

Language：English   Presentation type：Oral presentation (general)  

Venue：Online  

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Event date： 2020.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン  

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Event date： 2020.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン  

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Event date： 2020.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン  

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Event date： 2019.11

Language：English   Presentation type：Oral presentation (invited, special)  

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Event date： 2019.6

Language：English   Presentation type：Oral presentation (keynote)  

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Event date： 2018.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：神戸大学鶴甲第1キャンパス  

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Event date： 2018.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：東京理科大学（野田キャンパス）  

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Event date： 2018.3

Language：English   Presentation type：Oral presentation (general)  

Venue：日本大学理工学部（船橋キャンパス）  

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Event date： 2018.3

Language：English   Presentation type：Poster presentation  

Venue：日本大学理工学部（船橋キャンパス）  

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Event date： 2018.3

Language：English   Presentation type：Poster presentation  

Venue：日本大学理工学部（船橋キャンパス）  

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Event date： 2017.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：岩手大学  

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Event date： 2017.9

Language：Japanese   Presentation type：Poster presentation  

Venue：神戸大学鶴甲第1キャンパス  

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Event date： 2017.9

Language：English   Presentation type：Poster presentation  

Venue：神戸大学鶴甲第1キャンパス  

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Event date： 2017.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：神戸大学鶴甲第1キャンパス  

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Event date： 2017.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：神戸大学鶴甲第1キャンパス  

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Event date： 2017.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：慶応大学（日吉キャンパス）  

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Event date： 2017.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：慶應大学（日吉キャンパス）  

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Event date： 2017.3

Language：English   Presentation type：Poster presentation  

Venue：慶応大学（日吉キャンパス）  

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Event date： 2016.9

Language：Japanese   Presentation type：Poster presentation  

Venue：北海道教育大学旭川校  

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Event date： 2016.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：北海道教育大学旭川校  

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Event date： 2016.9

Language：Japanese   Presentation type：Poster presentation  

Venue：北海道教育大学旭川校  

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Event date： 2016.9

Language：English   Presentation type：Oral presentation (general)  

Venue：北海道教育大学旭川校  

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Event date： 2016.9

Language：Japanese   Presentation type：Poster presentation  

Venue：北海道教育大学旭川校  

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Event date： 2016.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：金沢大学（角間キャンパス）  

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Event date： 2016.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：金沢大学（角間キャンパス）  

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Event date： 2016.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：立命館大学京田辺キャンパス  

基板上の微小管の座屈現象から、1本の高分子鎖としての機械的強度について考察を行った。

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Event date： 2016.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：立命館大学京田辺キャンパス  

ハスの葉のダブルラフネス構造を模倣した表面構造を持つ有機化合物の薄膜の作製に成功した結果を示すとともに、なぜ超撥水性を示すのかについて理論的考察を行った。

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Event date： 2016.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：立命館大学京田辺キャンパス  

超親水性を示す有機化合物の表面の濡れ性について発表した。

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Event date： 2016.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：東北学院大学  

ハスの葉を模倣した表面を持つ有機化合物の薄膜の作製に成功した。また、表面構造との超撥水性について理論的考察を行った。

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Event date： 2015.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：関西大学 千里山キャンパス  

ハスの葉の上の水滴が転がる現象を水滴の位置エネルギーとピン止めエネルギーから説明できることを明らかにした。

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Event date： 2015.9

Language：Japanese   Presentation type：Poster presentation  

Venue：関西大学 千里山キャンパス  

微小管の破壊現象から微小管のヤング率を理論的に評価した。その結果、これまで報告されている値をすべて網羅する理論的な結果を得た。

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Event date： 2015.9

Language：English   Presentation type：Oral presentation (general)  

Venue：関西大学 千里山キャンパス  

疎水性表面に開いた孔に水滴が浸み込む条件について実験と理論の両面から研究を行った。

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Event date： 2015.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：鹿児島大学郡元キャンパス  

傾いたハスの葉の表面上で水滴が転がる機構を明らかにした。

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Event date： 2015.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：鹿児島大学郡元キャンパス  

疎水性表面に開いた孔に水滴が浸み込む機構を明らかにした。

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Event date： 2015.5

Language：English   Presentation type：Poster presentation  

Venue：Convention Center, Rheingoldhalle, Rheinstrasse 66, 55116, Mainz, Germany  

傾いたハスの葉の上で水滴が転がる機構を明らかにした。

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Event date： 2015.5

Language：English   Presentation type：Oral presentation (general)  

Venue：Convention Center, Rheingoldhalle, Rheinstrasse 66, 55116, Mainz, Germany  

疎水性表面に開いた孔に水滴が浸み込む条件を実験と理論の両面から研究を行った。

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Event date： 2015.3

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2015.3

Language：English   Presentation type：Oral presentation (general)  

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Event date： 2015.3

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2015.1

Language：Japanese   Presentation type：Oral presentation (invited, special)  

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Event date： 2014.11

Language：Japanese   Presentation type：Oral presentation (invited, special)  

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Event date： 2014.9

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2014.9

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2014.9

Language：Japanese   Presentation type：Poster presentation  

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Event date： 2014.9

Language：Japanese   Presentation type：Poster presentation  

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Event date： 2014.9

Language：Japanese   Presentation type：Poster presentation  

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Event date： 2014.3

Language：Japanese   Presentation type：Oral presentation (general)  

名古屋大学（東山キャンパス）

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Event date： 2014.3

Language：Japanese   Presentation type：Poster presentation  

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Event date： 2014.3

Language：Japanese   Presentation type：Poster presentation  

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Event date： 2014.3

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2013.12

Language：Japanese   Presentation type：Poster presentation  

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Event date： 2013.9

Language：Japanese   Presentation type：Poster presentation  

Venue：徳島大学常三島キャンパス  

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Event date： 2013.9

Language：Japanese   Presentation type：Poster presentation  

Venue：徳島大学常三島キャンパス  

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Event date： 2013.9

Language：Japanese   Presentation type：Poster presentation  

Venue：名古屋工業大学  

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Event date： 2013.9

Language：Japanese   Presentation type：Poster presentation  

Venue：名古屋工業大学  

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Event date： 2013.9

Language：Japanese   Presentation type：Poster presentation  

Venue：名古屋工業大学  

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Event date： 2013.9

Language：Japanese   Presentation type：Poster presentation  

Venue：名古屋工業大学  

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Event date： 2013.3

Language：Japanese   Presentation type：Poster presentation  

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Event date： 2013.3

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2013.3

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2013.2

Language：Japanese   Presentation type：Oral presentation (invited, special)  

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Event date： 2012.9

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2012.9

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2011.6 - 2011.7

Language：English   Presentation type：Oral presentation (invited, special)  

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Event date： 2010.9

Language：Japanese   Presentation type：Oral presentation (invited, special)  

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毎年9月に開催されるコロイドおよび界面化学討論会の開催に関する業務作業を行う

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日本化学会 コロイドおよび界面化学部会の長期的な運営や施策を議論する

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コロイドおよび界面化学部会のホームページ運営管理責任者
2022年3月1日～2023年2月28日 ホームページ更新 40回

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2020年8月～2022年3月 査読50件
2022年4～12月 査読30件
2023年1～3月 査読15件
2023年4月～12月 査読50件

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学会開催のための企業誘致活動、広報活動

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日本化学会 コロイドおよび界面化学部会の全体運営

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コロイドおよび界面化学部会で年４回発行している機関紙に関する編集業務

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コロイドおよび界面化学部会のホームページ運営管理

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2016年9月22-24日に北海道教育大学旭川校で開催された第67回コロイドおよび界面化学討論会の実行委員を努めた。

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コロイドおよび界面化学部会のホームページ運営管理

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