研究者詳細 - 永島　壮

論文 - 永島　壮

分割表示 >> ／全件表示 45 件中 1 - 45 件目

Capillarity-induced fold localization in film–substrate systems 査読有り

S. Nagashima, R. Ota, S. Matsubara, D. Okumura

Interface Focus 2025年3月

Tunable wrinkles in diamond-like carbon films on PDMS substrates 査読有り

Nagashima, S; Hasebe, T; Hotta, A; Suzuki, T

Diam. Relat. Mater. 151 巻頁： 11855 2025年1月

担当区分：筆頭著者,　責任著者記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Diamond and Related Materials

Diamond-like carbon (DLC) films are widely used in engineering applications owing to their excellent mechanical, optical, and biological properties. However, the simple deposition of a DLC film on a soft polymer, including poly(dimethylsiloxane) (PDMS), results in a coarsened surface composed of instability-induced hierarchical wrinkles with limited ability to adjust the dimensions. Overcoming this issue would help create fabrication opportunities for functional surfaces. Here, we demonstrate the controlled formation of wrinkles with tunable wavelengths and amplitudes on the surface of DLC-coated PDMS substrates. Pre-treatment of the substrates with Ar plasma prior to film deposition allows for the formation of wrinkles without structural hierarchy. The wavelength and amplitude can be controlled by adjusting the duration of the plasma treatment while maintaining the film thickness constant. The static contact angles of water droplets on the wrinkled surfaces remain nearly constant regardless of the wavelength of the wrinkles. These tunable wrinkles in DLC films on PDMS substrates have potential engineering applications, including cell scaffolds.

DOI： 10.1016/j.diamond.2024.111855

Web of Science

Scopus

水フィラメントに駆動されるリンクル・フォールド変態の数値解析査読有り

太田陸斗, 永島壮, 松原成志朗, 奥村大

計算数理工学論文集 24 巻頁： 05-241213 2024年12月

クリースの形成に及ぼすひずみ第二不変量の影響査読有り

岡村太暉, 松原成志朗, 永島壮, 奥村大

計算数理工学論文集 24 巻頁： 06-241213 2024年12月

ノンレシプロカルゲルの異常ポインティング効果査読有り

野々垣翔真, Yunlei Zhang, 松原成志朗, 永島壮, 石田康博, 奥村大

計算数理工学論文集 24 巻頁： 04-241213 2024年12月

Inhomogeneous instability patterns in polyacrylamide hydrogel bilayers 査読有り

S. Nagashima, W. Uchiyama, S. Hayashi, S. Matsubara, D. Okumura

Mech. Eng. J 2024年11月

Crease instability in Gent-Gent hyperelastic materials Open Access

Matsubara, S; Kobayashi, K; Ishida, T; Nagashima, S; Okumura, D

Int. J. Mech. Sci. 280 巻頁： 109549 - 109549 2024年10月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：International Journal of Mechanical Sciences

We study the crease instability of an incompressible Gent-Gent elastomer under general loading conditions. The Gent-Gent model has two distinct characteristics: the logarithmic nonlinearity triggered by I2 energy term and the strain hardening due to limiting chain extensibility. By performing finite element analysis combined with an evaluation of surface tension, we investigate the effects of the two characteristics on the critical creasing onset and the creasing onset delayed by surface tension. The results show that uniaxial compression induces logarithmic nonlinearity that accelerates the critical creasing onset, whereas equibiaxial compression hastens the initiation of strain hardening that delays the critical creasing onset. In addition, logarithmic nonlinearity mitigates the delay in creasing onset caused by surface tension under the uniaxial condition, and strain hardening suppresses creasing in cooperation with surface tension under the equibiaxial condition. Conversely, under the plane strain condition, two characteristics have little effect on the creasing onset delayed by surface tension.

DOI： 10.1016/j.ijmecsci.2024.109549

Open Access

Web of Science

Scopus

Deformation in the wrinkle-crease transformation 査読有り

Ishida, T; Matsubara, S; Nagashima, S; Okumura, D

Int. J. Solids Struct. 298 巻頁： 112876 - 112876 2024年7月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：International Journal of Solids and Structures

We investigate deformation in the wrinkle–crease transformation to reveal the missing link between the wrinkling and creasing instabilities, which occur on the surface of elastomers under compression. Plane-strain finite element (FE) analysis is performed by combining a nonlinear perturbation approach to find two bifurcated solutions for the flat surface in a metastable state. The first solution is the stable deformation path for crease evolution, and the second solution is the previously unknown unstable deformation path from wrinkling to creasing. The two deformation paths are not independent, and they are connected at the critical strain for creasing εC. The resulting deformation at εC acts as a precursive deformation to cause creasing. Although the unstable path is initiated by the wrinkling instability as a bifurcation, the creasing instability (i.e., εC) is interpreted as the singular point at which the unstable path switches to the stable path. A chain reaction model is developed to describe the mechanism and deformation of the wrinkle–crease transformation, and it shows good agreement with the FE prediction within an inevitable limitation of FEs.

DOI： 10.1016/j.ijsolstr.2024.112876

Web of Science

Scopus

Computational and physical aspects for the occurrence of crease in an elastomer under general loading conditions 査読有り

Matsubara, S; Ogino, A; Nagashima, S; Okumura, D

Int. J. Solids Struct. 288 巻 2024年2月

記述言語：英語出版者・発行元：International Journal of Solids and Structures

We study the occurrence of crease in an elastomer under three loading conditions from both computational and physical points of view. A two-dimensional finite element analysis, including a perturbation force-based approach, is performed to detect the stable creased state, where the crease formation is completed. A mesh convergence study for the energy release and crease depth in the creased state provides a guideline for the finite element mesh requisite for predicting the occurrence of crease. We also visualize the mesh convergence for the critical creasing onset by plotting the set of compressive strain and mesh resolution at the point where the energy release is zero. In addition, the present evaluation method of the surface tension using the energy release and surface area change for an elastomer with a traction-free surface yields a good prediction for the creasing onset delayed by surface tension without additional numerical implementations or adjustment parameters. This facilitates the comprehensive study of the creasing onset delayed by the surface tension under general loading conditions. The results reveal that tensile deformation in the out-of-plane direction encourages the retardation of the creasing onset via the extension of the width and the energy emission. We further demonstrate that energetically preferential crease interval can be used to evaluate the spacing between creases delayed by moderate surface tension.

DOI： 10.1016/j.ijsolstr.2023.112610

Web of Science

Scopus

表面張力による固体と液体の相互運動のフェーズフィールド解析

纐纈拓己, 中谷彰宏, 土井祐介, 永島壮

関西支部講演会講演論文集 2024.99 巻 ( 0 ) 頁： 20207 2024年

記述言語：日本語出版者・発行元：一般社団法人日本機械学会

<p>現在，固体の形状の変化を利用した例として，二次元テンプレートを三次元構造物へ自己組織化するという技術が注目されている．液体と固体の間に作用する表面張力が，固体の構造に影響を及ぼすことが分かっている．本研究では構造の時間変化を直接扱うことができるフェーズフィールド法を用いて，固体が動いた場合の液体の挙動の解析を行った．</p>

DOI： 10.1299/jsmekansai.2024.99.20207

CiNii Research

均質化解析によるノンレシプロカルゲルの引張・圧縮非対称性評価

布施卓馬, 松原成志朗, 永島壮, 奥村大

計算数理工学論文集 23 巻 ( 0 ) 頁： 137 - 142 2023年11月

ノンレシプロカルゲルの円筒押込み大変形解析

野々垣翔真, 松原成志朗, 永島壮, 奥村大

計算数理工学論文集 23 巻 ( 0 ) 頁： 123 - 128 2023年11月

クリースの発達過程に対する影響因子の調査査読有り

石田竜也, 永島壮, 松原成志朗, 奥村大

計算数理工学論文集 23 巻頁： 20-231124 2023年11月

Visualization and analysis of skin strain distribution in various human facial actions 査読有り

T. Misu, H. Ishihara, S. Nagashima, Y. Doi and A. Nakatani

Mech. Eng. J. 2023年9月

Time-swelling superposition principle for the linear viscoelastic properties of polyacrylamide hydrogels 査読有り

S. Matsubara, A. Takashima, S. Nagashima, S. Ida, H. Tanaka, M. Uchida and D. Okumura

Adv. Struct. Mater. 2023年8月

Bio-Inspired Instability-Induced Hierarchical Patterns Having Tunable Anisotropic Wetting Properties《掲載号Front Cover選出》査読有り

Nagashima, S; Suzuki, K; Matsubara, S; Okumura, D

Adv. Mater. Interfaces 10 巻 ( 14 ) 頁： 2300039 2023年5月

担当区分：筆頭著者,　責任著者記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Advanced Materials Interfaces

This paper introduces a method for the bottom-up fabrication of bio-inspired hierarchical patterns having tunable anisotropic wetting properties. The method exploits the surface instability of bilayers comprising a gold nanofilm attached to a substantially prestretched elastomer substrate. Upon film formation, highly aligned wrinkles spontaneously form on the surface owing to the surface instability driven by the compressive residual stress in the film. Thereafter, uniaxial compressive strain is applied to the film by prestretch relaxation of the substrate, which generates an array of high-aspect-ratio ridges on the surface. Consequently, hierarchical patterns comprising unidirectionally aligned ridges covered with wrinkles are obtained. Water droplets placed on surfaces having the aforementioned hierarchical patterns show direction-dependent contact angles, resulting in elongated shapes, which indicates the presence of anisotropic wetting properties. The magnitude of wetting anisotropy can be tuned by simple control of the applied compressive strain and film thickness.

DOI： 10.1002/admi.202300039

Web of Science

Scopus

Self-Wrinkling in Polyacrylamide Hydrogel Bilayers《掲載号Supplementary Cover選出》査読有り

Nagashima, S; Akamatsu, N; Cheng, XF; Matsubara, S; Ida, S; Tanaka, H; Uchida, M; Okumura, D

Langmuir 39 巻 ( 11 ) 頁： 3942 - 3950 2023年3月

担当区分：筆頭著者,　責任著者記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Langmuir

Swelling of a gel film attached to a soft substrate can induce surface instability, which results in the formation of highly ordered patterns such as wrinkles and folds. This phenomenon has been exploited to fabricate functional devices and rationalize morphogenesis. However, obtaining centimeter-scale patterns without immersing the film in a solvent remains challenging. Here, we show that wrinkles with wavelengths of up to a few centimeters can be spontaneously created during the open-air fabrication of film-substrate bilayers of polyacrylamide (PAAm) hydrogels. When the film of an aqueous pregel solution of acrylamide prepared on the PAAm hydrogel substrate undergoes open-air gelation, hexagonally packed dimples initially emerge on the surface, which later evolve into randomly oriented wrinkles. The formation of such self-organized patterns can be attributed to the surface instability resulting from autonomous water transport in the bilayer system during open-air fabrication. The temporal evolution of the patterns can be ascribed to an increase in overstress in the hydrogel film due to continued water uptake. The wrinkle wavelength can be controlled in the centimeter-scale range by adjusting the film thickness of the aqueous pregel solution. Our self-wrinkling method provides a simple mechanism for the generation of swelling-induced centimeter-scale wrinkles without requiring an external solvent, which is unachievable with conventional approaches.

DOI： 10.1021/acs.langmuir.2c03264

Web of Science

Scopus

PubMed

リッジパターン変態のプレストレッチ依存性と分岐座屈特性査読有り

田中大地, 若林駿人, 松原成志朗, 永島壮, 奥村大

計算数理工学論文集 22 巻頁： 117 - 122 2022年12月

薄膜リンクル招待有り

永島壮

材料 71 巻 ( 8 ) 頁： 727 - 727 2022年8月

材料シンポジウム「若手学生研究発表会」招待有り

永島壮, 野口泰隆

材料 71 巻 ( 4 ) 頁： 415 - 415 2022年4月

Wrinkle-Assisted Capillary Bridging for the Directed Assembly of Single-Level DNA Nanowire Arrays 査読有り国際共著

Nagashima, S; Yoon, SM; Kim, D; Nakatani, A; Moon, MW

Adv. Mater. Interfaces 9 巻 ( 6 ) 頁： 2102243 - 2102243 2022年2月

担当区分：筆頭著者,　責任著者記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Advanced Materials Interfaces

Assembly of molecular-scale nanowire arrays with defined spacing in an inexpensive and time-efficient manner enables the development of versatile functional nanodevices that are unattainable with conventional approaches involving top-down patterning techniques. This paper introduces a bottom-up method for rapidly assembling DNA molecules into periodically aligned 2-nm-thin nanowires. The method uses wettability-contrast channels composed of superhydrophilic wrinkles with a periodic high-aspect-ratio structure as the top and a hydrophobic flat surface as the bottom. After injecting the channels with DNA solution, one end of the wrinkled top is detached to facilitate unidirectional receding of an array of submicrometer-scale capillary bridges developed in between. The molecules confined in each capillary bridge are then made to evaporatively assemble into a linear structure on the flat surface, thus yielding an array of molecular-scale nanowires. The inter-nanowire separation can be controlled by tuning the wrinkle dimensions. The wrinkle-assisted capillary-bridging method, termed WaCaB, exploits the surface instability of a film–substrate system for wrinkle fabrication and employs a simple detachment process, thus offering a general and flexible pathway for the facile assembly of spatially organized single-level DNA nanowires, which can create new fabrication opportunities for devices in nanoelectronics, photonics, and biology.

DOI： 10.1002/admi.202102243

Web of Science

Scopus

Diversity of the bifurcations and deformations on films bonded to soft substrates: Robustness of the herringbone pattern and its cognate patterns 査読有り

Kikuchi, S; Matsubara, S; Nagashima, S; Okumura, D

J. Mech. Phys. Solids 159 巻 2022年2月

記述言語：英語出版者・発行元：Journal of the Mechanics and Physics of Solids

In this study, we investigate the diversity of the bifurcations and deformations during evolution of periodic patterns on compressed films bonded to compliant substrates. Three-dimensional finite element analysis is performed assuming that the first bifurcation has either the hexagonal or square (i.e., checkerboard) dimple mode. Step-by-step eigenvalue buckling analysis is performed to explore sequential bifurcations on the bifurcated paths. It is found that at the second bifurcation, a rectangular checkerboard or stripe mode occurs depending not only on the Young's modulus ratio of the film and substrate, but also on the magnitude of the imperfection prescribed by the first bifurcation mode. Different bifurcation modes give a family of herringbone deformation patterns with different dimensions, i.e., the evolutional process is multiple and robust. Further, superposition of the identical modes in symmetric directions elucidates the existence of distinctive patterns cognate with the herringbone pattern, including a variety of experimentally observed patterns.

DOI： 10.1016/j.jmps.2021.104757

Web of Science

Scopus

弾性体に誘起するクリースの発生と伝播の有限要素解析

松原成志朗, 星亮吾, 永島壮, 奥村大

理論応用力学講演会講演論文集 66 巻 ( 0 ) 頁： 5 2022年

記述言語：日本語出版者・発行元：日本学術会議「機械工学委員会・土木工学・建築学委員会合同IUTAM分科会」

<p>クリースは圧縮負荷が作用する弾性体の自由表面上で鋭い溝のような変形として発生する．クリースは弾性体の自由表面上で伝播して脳のしわなどに見られる特徴的なパターンを形成する．クリースの伝播は，直前のクリースが形成する不均質な変位場がトリガーとなると予想されるが，詳細なメカニズムはわかっていない．また，各々のクリースには固有間隔が存在し得るものの，これを決める要因についてもわかっていない．本研究では，V字型欠陥を有するに対して二つの異なるアプローチでクリースの発生と伝播の有限要素解析を実施し，逐次的なクリースの発生機構と固有間隔を規定する要因を明らかにする．</p>

DOI： 10.11345/japannctam.66.0_5

CiNii Research

リッジパターン変態のプレストレッチ依存性と分岐座屈特性査読有り

田中大地, 若林駿人, 松原成志朗, 永島壮, 奥村大

計算数理工学論文集 22 巻頁： 117 - 121 2022年

Diversity of the bifurcations and deformations on films bonded to soft substrates: robustness of the herringbone pattern and its cognate patterns 査読有り

S. Kikuchi, S. Matsubara, S. Nagashima, D. Okumura

J. Mech. Phys. Solids 159 巻頁： 10457 2021年12月

ヘリンボン及びトリプルジャンクションパターンの発達に対する影響因子解析査読有り

田中大地, 菊池正太郎, 松原成志朗, 永島壮, 奥村大

計算数理工学論文集 21 巻頁： 09-211218 2021年11月

体心立方結晶における非線形エネルギー局在振動の探索査読有り

土井祐介，小宮拓也，永島　壮，中谷彰宏

材料 70 巻頁： 330 - 335 2021年4月

Capillary-induced wrinkle-to-fold transitions under biaxial compression《掲載号 Front Cover 選出》査読有り

S. Nagashima, A. Nakatani

Langmuir 37 巻 ( 17 ) 頁： 5282 - 5289 2021年4月

Spontaneous formation of aligned DNA nanowires by capillarity-induced skin folding 査読有り国際共著

S. Nagashima, H. D. Ha, D. H. Kim, A. Kosmrlj, H. A. Stone and M.-W. Moon

Proc. Natl. Acad. Sci. USA 114 巻頁： 6233 - 6237 2017年

Time course analysis of antithrombogenic properties of fluorinated diamond-like carbon coating determined via accelerated aging tests: Quality control for medical device commercialization 査読有り

S. Maegawa, T. Hasebe, Y. Yamato, K. Bito, S. Nagashima, T. Hayashi, T. Mine, T. Matsumoto, A. Hotta and T. Suzuki

Diam. Relat. Mater. 70 巻頁： 33 - 38 2016年

Tunable nanochannels fabricated by mechanical wrinkling/folding of a stiff skin on a soft polymer《掲載号Back Cover選定》査読有り国際共著

S. Nagashima, H. Ebrahimi, K.-R. Lee, A. Vaziri and M.-W. Moon

Adv. Mater. Interfaces 2 巻頁： 1400493 2015年

Self-assembled folding of a biaxially compressed film on a compliant substrate 査読有り国際共著

Sk. F. Ahmed, S. Nagashima, J. Y. Lee, K.-R. Lee, K.-S. Kim and M.-W. Moon

Carbon 76 巻頁： 105 - 112 2014年

Adhesion behavior of mouse liver cancer cells on nanostructured superhydrophobic and superhydrophilic surfaces 査読有り国際共著

T.-J. Ko, E. Kim, S. Nagashima, K. H. Oh, K.-R. Lee, S. Kim and M.-W. Moon

Soft Matter 9 巻頁： 8705 - 8711 2013年

Hardness and surface roughness of hydrogenated amorphous carbon-based films synthesized by atmospheric pressure-plasma enhanced chemical vapor deposition at low temperature 査読有り

M. Noborisaka, R. Horikoshi, S. Nagashima, A. Shirakura and T. Suzuki

Thin Solid Films 527 巻頁： 114 - 119 2013年

Ultrastructural characterization of surface induced-platelet activation on articial materials by transmission electron microscopy 査読有り

Y. Yoshimoto, T. Hasebe, K. Takahashi, M. Amari, S. Nagashima, A. Kamijo, A. Hotta, K. Takahashi and T. Suzuki

Microsc. Res. Tech. 76 巻頁： 342 - 349 2013年

Hydrophobicity and non-thrombogenicity of nanoscale dual rough surface coated with uorine-incorporated diamond-like carbon films: Biomimetic surface for blood-contacting medical devices 査読有り国際共著

T. Hasebe, S. Nagashima, A. Kamijo, M.-W. Moon, Y. Kashiwagi, A. Hotta, K.-R. Lee, K. Takahashi, T. Yamagami and T. Suzuki

Diam. Relat. Mater. 38 巻頁： 14 - 18 2013年

Controlled formation of wrinkled diamond-like carbon (DLC) film on grooved poly(dimethylsiloxane) substrate 査読有り

S. Nagashima, T. Hasebe, D. Tsuya, T. Horikoshi, M. Ochiai, S. Tanigawa, Y. Koide, A. Hotta and T. Suzuki

Diam. Relat. Mater. 22 巻頁： 48 - 51 2012年

Tailoring surface topographies of polymers by using ion beam: Recent advances and the potential applications in biomedical and tissue engineering 査読有り

T. Hasebe*, S. Nagashima* (*equal contribution), Y. Yoshimoto, A. Hotta and T. Suzuki

Nucl. Instr. Meth. B 282 巻頁： 134 - 136 2012年

Synthesis of transparent and hard SiOC(–H) thin films on polycarbonate substrates by PECVD method 査読有り

M. Noborisaka, H. Kodama, S. Nagashima, A. Shirakura, T. Horiuchi and T. Hasebe

Surf. Coat. Technol. 206 巻頁： 2581 - 2584 2012年

Human umbilical vein endothelial cell interaction with fluorine-incorporated amorphous carbon films 査読有り

Y. Yoshimoto, T. Hasebe, S. Nagashima, A. Kamijo, T. Nakatani, T. Yamagami, N. Kitamura, T. Kitagawa, A. Hotta, K. Takahashi and T. Suzuki

Jpn. J. Appl. Phys. 51 巻頁： 090129 2012年

Combining polymers with diamond-like carbon (DLC) for highly functionalized materials 査読有り

R. Asakawa*, S. Nagashima* (*equal contribution), Y. Nakamura, T. Hasebe, T. Suzuki and A. Hotta

Surf. Coat. Technol. 206 巻頁： 676 - 685 2011年

Design for improved adhesion of fluorine-incorporated hydrogenated amorphous carbon on metallic stent: Three-layered structure with controlled surface free energy 査読有り

T. Hasebe, K. Murakami, S. Nagashima, Y. Yoshimoto, A. Ihara, M. Otake, R. Kasai, S. Kasuya, N. Kitamura, A. Kamijo, H. Terada, A. Hotta, K. Takahashi and T. Suzuki

Diam. Relat. Mater. 20 巻頁： 902 - 906 2011年

The evaluation of reusability of diamond-like carbon (DLC) coated PET bottles with respect to gas barrier and anti-contamination properties 査読有り

A. Shirakura, Y. Yoshimoto, S. Nagashima and T. Suzuki

J. Appl. Pack. Res. 5 巻頁： 227 - 236 2011年

Effect of oxygen plasma treatment on non-thrombogenicity of diamond-like carbon films 査読有り

S. Nagashima, T. Hasebe, A. Kamijo, Y. Yoshimoto, A. Hotta, H. Morita, H. Terada, M. Tanaka, K. Takahashi and T. Suzuki

Diam. Relat. Mater. 19 巻頁： 861 - 865 2010年

Depth proling of fluorine-doped diamond-like carbon (F-DLC) film: Localized uorine in the top-most thin layer can enhance the non-thrombogenic properties of F-DLC 査読有り

T. Hasebe*, S. Nagashima* (*equal contribution), A. Kamijo, T. Yoshimura, T. Ishimaru, Y. Yoshimoto, S. Yohena, H. Kodama, A. Hotta, K. Takahashi and T. Suzuki

Thin Solid Films 516 巻頁： 299 - 303 2007年

　前のページ - 次のページ　

<永島 壮>

論文 - 永島 壮

<永島　壮>

論文 - 永島　壮