Chiba, Ayano

写真a

Affiliation

Faculty of Science and Technology, Department of Physics (Yagami)

Position

Assistant Professor/Senior Assistant Professor

Related Websites

External Links

Career 【 Display / hide

  • 2003.04
    -
    2003.11

    Kyoto university, Department of physics, JSPS Fellow

  • 2003.12
    -
    2005.08

    Kyoto university, Department of engineerig, JSPS Fellow

  • 2005.09
    -
    2007.03

    Keio university, Instructor

  • 2007.02
    -
    2008.03

    Rutherford Appleton Laboratory, Visiting Scientist

  • 2007.04
    -
    2013.03

    Assistant Professor, Keio University

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Academic Background 【 Display / hide

  • 1998.03

    Kyoto University, Faculty of Science

    University, Graduated

  • 2000.03

    Kyoto University, Graduate School, Division of Natural Science, Department of Physics

    Graduate School, Completed, Master's course

  • 2003.11

    Kyoto University, Graduate School, Division of Natural Science, Department of Physics

    Graduate School, Completed, Doctoral course

Academic Degrees 【 Display / hide

  • PhD, Kyoto University, Coursework, 2003.11

 

Research Areas 【 Display / hide

  • Condensed matter physics II (Physical Properties II)

Research Keywords 【 Display / hide

  • Liquids

  • Polymer

  • Disordered Systems

  • Molecular absorption

  • Phase Transition

 

Papers 【 Display / hide

  • Longitudinal acoustic and higher-energy excitations in the liquid phase-change material Ge2Sb2Te5

    Inui M., Kajihara Y., Hosokawa S., Chiba A., Nakajima Y., Matsuda K., Tsuchiya Y., Stellhorn J.R., Hagiya T., Uchiyama H., Tsutsui S., Baron A.Q.R.

    Physical Review B (Physical Review B)  104 ( 6 )  2021.08

    ISSN  24699950

     View Summary

    The dynamic structure factor S(Q,E) of liquid Ge2Sb2Te5 has been obtained by inelastic x-ray scattering, where Q and E are momentum and energy transfer, respectively. The dispersion curve of the longitudinal acoustic excitation energy exhibits flat-topped Q dependence similarly to that in liquid GeTe and liquid Bi, where the local structure is modulated by Peierls distortion. The flat-topped energy in liquid Ge2Sb2Te5 is split into low and high energy parts arising from Sb-Te and Ge-Te correlations, respectively. Furthermore, the high energy part depends on Q like an optical mode with decreasing Q to zero, and it approaches the vibrational energy of fourfold coordinated Ge atoms with octahedral configurations. The result indicates that a majority of Ge in the liquid stays in octahedral order as predicted by first-principles molecular dynamics simulations.

  • Streak Patterns Observed in Small Angle X-Ray Scattering from Highly Oriented Pyrolytic Graphite (HOPG)

    Ohmasa Y., Chiba A.

    Zeitschrift fur Physikalische Chemie (Zeitschrift fur Physikalische Chemie)  235 ( 1-2 ) 37 - 57 2020

    ISSN  09429352

     View Summary

    © 2020 Walter de Gruyter GmbH, Berlin/Boston. Various forms of streak patterns are observed in small angle X-ray scattering from Highly Oriented Pyrolytic Graphite (HOPG). The streak patterns are assigned as specular reflection, double Bragg scattering, and diffuse + Bragg double scattering. These scatterings contain various information on the mesoscopic structures of the HOPG sample.

  • Confined Space Enables Spontaneous Liquid Separation by Molecular Size: Selective Absorption of Alkanes into a Polyolefin Cast Film

    Ayano Chiba, Akio Oshima,and Ryo Akiyama

    Langmuir (ACS Publications)  35 ( 52 ) 17177 - 17184 2019.11

    Research paper (scientific journal), Joint Work, Accepted,  ISSN  0743-7463

     View Summary

    © 2019 American Chemical Society. The depletion force has been used to explain phase separation phenomena in colloidal systems. Here, we showed that depletion force can explain not only phase separation of large and small colloidal particles but also preferential absorption of larger molecules from a mixture of large and small molecules in a liquid state. When a polyolefin cast film was immersed in a mixture of long and short normal alkanes, the longer molecules were selectively absorbed into the film. This experimental result was explained from the viewpoint of depletion force. The main finding was the use of confined space to emphasize the separation tendency caused by the force. In general, the increase in entropy may serve as a driving force to mix molecules. However, if sufficiently narrow pores are present, large and small molecules are separated naturally by size as the entropy increases. This finding will lead to size exclusion chromatography of low-mass molecules, similar to gel permeation chromatography of macromolecules. In order to demonstrate the effect of depletion force, we selected and experimented with a system based on a polyolefin isotactic poly(4-methyl-1-pentene) (P4MP1) film and a normal alkane mixture and realized high molecular selectivity. The P4MP1 film we used can be prepared simply by evaporating the solvent from the solution and casting the film. On the basis of the Asakura-Oosawa theory, we concluded that spontaneous and high molecular selectivity is attributed to the depletion force provided by the small sub-nanopores with uniform size in the film.

  • Structural studies on fluid sulfur at high temperatures and high pressures: I. Atomic dynamics investigated by inelastic x-ray scattering

    Inui M., Kajihara Y., Chiba A., Matsuda K., Tsutsui S., Baron A.

    Journal of Non-Crystalline Solids (Journal of Non-Crystalline Solids)  522 2019.10

    ISSN  00223093

     View Summary

    © 2019 Elsevier B.V. Inelastic x-ray scattering spectra of fluid S were measured from 403 K near the melting point to 1343 K in the supercritical region at 25 MPa. Although the dynamic structure factor in the supercritical region exhibits a single peak profile, the spectrum includes collective inelastic excitations besides the quasielastic component. The acoustic excitation energy in the supercritical region is close to the one predicted by the sound speed in the fluid consisting of S8 molecules and the observed excitation energies of the stretching modes in S molecules suggest that few fraction of S2 molecules in the supercritical region near the liquid-vapor critical point. This result indicates that the nearest neighbor coordination number in the supercritical fluid S obtained by x-ray diffraction [Inui et al., J. Phys. Conf. Ser. 98 (2008) 012008] was underestimated.

  • Diffuse + Bragg double scattering and specular reflection observed in the small-angle X-ray scattering from highly oriented pyrolytic graphite

    Y. Ohmasa, A. Chiba

    Journal of Applied Crystallography (International Union of Crystallography (IUCr))  52 ( 3 ) 652 - 664 2019.06

    Research paper (scientific journal), Joint Work, Accepted,  ISSN  1600-5767

     View Summary

    © International Union of Crystallography, 2019 In the small-angle scattering from as-prepared and neutron-irradiated highly oriented pyrolytic graphite samples, a new type of streak pattern is observed near the -type double Bragg scattering. This newly observed scattering is assigned as the double scattering whose first scattering is diffuse scattering near the 00l Bragg scattering and whose second scattering is the Bragg scattering. Specular reflection from the surfaces of the crystallites or microcracks is also observed as a streak. These two types of scattering from the neutron-irradiated sample show oscillatory behavior, unlike that from the non-irradiated samples. The scattering is analyzed using the sharp-boundary model, and is explained by the assumptions that the non-irradiated sample has interfaces with a width of about 1 nm and the neutron-irradiated sample has a slab-like structure with a thickness of about 14 nm.

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Papers, etc., Registered in KOARA 【 Display / hide

Presentations 【 Display / hide

  • Selective absorption of longer alkane from alkane mixtures into a crystalline polyolefin as-cast film

    Ayano Chiba

    11th LIQUID MATTER CONFERENCE 2020/2021 (zoom (Prague, Czech Republic)) , 2021.07, Oral Presentation(general), European Physical Society (EPS)

  • Selective absorption of longer alkanes from alkane mixtures by a polyolefin film with pores

    Ayano Chiba

    Mini-Symposium on Liquids 2021 (MSL2021) (Okayama Univ.) , 2021.06, Oral Presentation(guest/special)

  • Structures and Phase Transformations of Polymer Melts

    Ayano Chiba

    第88回マテリアルズ・テーラリング研究会 (zoom 開催) , 2021.04, Oral Presentation(guest/special), マテリアルズ・テーラリング研究会事務局

  • Symposium lecture introduction

    Ayano Chiba

    2020 JPS Meeting (online meeting) , 2020.09, Oral Presentation(guest/special), JPS

  • Selective absorption of alkanes by pores in the crystal of polymer P4MP1 and its causes

    Ayano Chiba, Akio Oshima, Ryo Akiyama

    第69回高分子学会年次大会 (福岡国際会議場・福岡国際センター) , 2020.05, Oral Presentation(general), 公益社団法人 高分子学会

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Research Projects of Competitive Funds, etc. 【 Display / hide

  • エントロピー駆動液体分離

    2020.04
    -
    2023.03

    公益財団法人 旭硝子財団, 若手継続グラント, 千葉 文野, Research grant, Principal Investigator

  • Development and understanding of a new liquid separation method using pores in polymer crystals

    2019.11
    -
    2020.11

    The Sumitomo Foundation, Grant for Basic Science Research Projects, 千葉 文野, Research grant, Principal Investigator

  • エントロピー駆動の物質分離法:結晶空隙を用いた低分子サイズ排除クロマトグラフィー

    2019.04
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    2022.03

    MEXT,JSPS, Grant-in-Aid for Scientific Research, 千葉 文野, Grant-in-Aid for Scientific Research (C), Principal Investigator

  • 高分子結晶の空隙を用いた低分子のサイズ排除クロマトグラフィー

    2019.04
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    2020.03

    公益財団法人 双葉電子記念財団, 平成31年度 自然科学研究助成, 千葉 文野, Research grant, Principal Investigator

  • 2次元自己集積を利用した微粒子サイズ計測

    2018.06
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    2019.03

    株式会社資生堂, 資生堂 女性研究者サイエンスグラント, No Setting, Principal Investigator

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Works 【 Display / hide

  • 他大学セミナー講演

    千葉 文野

    愛媛大学理学部本館3階S31教室, 

    2015.12

    Other, Single

     View Details

    溶融高分子の圧力誘起構造変化: SiO2ガラスとの共通点を中心に

  • 他大学セミナー講演

    CHIBA AYANO

    首都大学東京 8号館302号室, 

    2013.11

    Other, Single

  • 他大学 一般公開講演

    CHIBA AYANO

    2013.10

    Other, Single

  • 他大学コロキウム講演

    CHIBA AYANO

    九州大学 箱崎キャンパス 物理 第3講義室, 

    2013.01

    Other, Single

  • TV出演

    CHIBA AYANO

    2012.12

    Other, Single

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Intellectual Property Rights, etc. 【 Display / hide

  • ポリオレフィン系重合体並びにそれを用いた有機化合物の吸着、吸蔵及び分離

    Application No.: 特願2020-56735  2020.03 

    Patent, Single, National application

  • ポリオレフィン系重合体並びにそれを用いた有機化合物の吸着、吸蔵及び分離

    Application No.: 特願2019-67703  2019.03 

    Patent, Single, National application

Awards 【 Display / hide

  • SCIENCE GRANT SHISEIDO FEMALE RESEARCHER

    2018.07, 株式会社 資生堂, 第11回資生堂 女性研究者サイエンスグラント

    Type of Award: Other Awards.  Country: 日本

 

Courses Taught 【 Display / hide

  • VIBRATIONS AND WAVES

    2021

  • PHYSICS LABORATORIES 2

    2021

  • PHYSICS LABORATORIES 1

    2021

  • LITERATURE OF PHYSICS

    2021

  • LABORATORY IN SCIENCE

    2021

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Social Activities 【 Display / hide

  • Photon Factory News (PFニュース)編集委員会

    2012.04
    -
    2014.03
  • 新学術領域研究専門委員会(2002_中性子地球科学)

    2009.12
    -
    2011.03

Memberships in Academic Societies 【 Display / hide

  • 日本化学会, 

    2013.04
    -
    Present
  • 日本高圧力学会, 

    2005.11
    -
    Present
  • 高分子学会, 

    2003.12
    -
    2005.11
  • 日本放射光学会, 

    2003.10
    -
    Present
  • 日本化学会, 

    2003.10
    -
    2004.09

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Committee Experiences 【 Display / hide

  • 2020.04
    -
    2022.03

    日本物理学会 会誌編集委員, 日本物理学会

  • 2019.11
    -
    Present

    中性子課題審査部会/P1利用研究課題審査委員, J-PARCセンター

  • 2018.09
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    2020.08

    評議員、渉外幹事, 日本高圧力学会

  • 2014.04
    -
    2015.03

    領域12 運営委員(化学物理), 日本物理学会

  • 2013.04
    -
    Present

    Member, 日本化学会

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