Updated on 2024/06/24

写真a

 
UMEDA, Noritaka
 
Affiliation
Affiliated organization, Waseda University Senior High School
Job title
Teacher (Affiliated Senior High School)

Research Experience

  • 2024.04
    -
    Now

    早稲田大学高等学院   教諭

  • 2005.04
    -
    2024.03

    成蹊中学・高等学校   教諭

  • 2002.04
    -
    2004.03

    共立女子第二中学校高等学校   教諭

Education Background

  • 2000.04
    -
    2002.03

    Waseda University   Graduate School of Science and Engineering  

  • 1996.04
    -
    2000.03

    Waseda University   School of Science and Engineering  

 

Papers

  • Sol-gel synthesis of a nanostructured hybrid material from an organosiloxane oligomer with a terminal phenyl group

    Atsushi Shimojima, Norimasa Atsumi, Noritaka Umeda, Yasuhiro Fujimoto, Kazuyuki Kuroda

    Journal of the Ceramic Society of Japan   114 ( 1334 ) 819 - 822  2006

     View Summary

    A novel ordered siloxane-organic hybrid material has been prepared by hydrolysis and polycondensation of a well-defined alkoxysilane precursor consisting of a tetrasiloxane unit and a 4-phenylbutyl group (1). Evaporation-induced self-assembly during hydrolysis and polycondensation of 1 led to the formation of a two-dimensional (2D) hexagonal mesostructure, which was revealed by X-ray diffraction (XRD) and transmission electron microscopy (TEM). Solid-state 13C CP/MAS NMR and 29Si MAS NMR confirmed that the product consisted of 4-phenylbutyl groups and siloxane networks, both of which are linked via Si-C bonds. These results will allow us to produce functional hybrid materials by chemical modification of phenyl groups, and also by incorporating other organic groups. Furthermore, calcination of this hybrid to remove organic groups led to the creation of an ordered microporous silica with the Brunauer-Emmett-Teller (BET) surface area of 570 m2 g-1 and the average pore diameter of 1.2 nm.

    DOI

    Scopus

    2
    Citation
    (Scopus)
  • Synthesis of multilayered silica-based hybrid films from difunctional organosilanes by co-hydrolysis and polycondensation with tetraalkoxysilane

    Noritaka Umeda, Atsushi Shimojima, Kazuyuki Kuroda

    Journal of Organometallic Chemistry   686 ( 1-2 ) 223 - 227  2003.12

     View Summary

    Decylethyldimethoxysilane (C10EtDMS) and didecyldimethoxysilane (2C10DMS) were used to prepare thin films of silica-based hybrids by co-hydrolysis and polycondensation with tetramethoxysilane (TMOS) followed by spin-coating. The length of the second alkyl chains (Et or n -decyl) had large effects on the formation of ordered hybrid films. In the case of C10EtDMS, transparent films of well-ordered lamellar hybrids were formed with various TMOS/C10EtDMS ratios by controlling the degree of polycondensation in the precursor solutions. In contrast, no ordered hybrids were obtained in the case of 2C10DMS under the same conditions, due to the larger steric hindrance of the longer second alkyl chain in the co-condensation. Increases of both TMOS/2C10DMS and HCl/Si ratios in the starting solutions promoted polycondensation and lead to the formation of ordered hybrid films. © 2003 Elsevier B.V. All rights reserved.

    DOI

    Scopus

    8
    Citation
    (Scopus)
  • Synthesis of layered inorganic-organic nanocomposite films from mono-, di-, and trimethoxy(alkyl)silane-tetramethoxysilane systems

    A. Shimojima, N. Umeda, K. Kuroda

    Chemistry of Materials   13 ( 10 ) 3610 - 3616  2001

     View Summary

    Transparent thin films of layered inorganic-organic nanocomposites were prepared by the sol-gel reactions of alkyldimethylmethoxysilane, alkylmethyldimethoxysilane, and alkyltrimethoxysilane in the presence of tetramethoxysilane followed by spin-coating. The macroscopic homogeneity and the nanostructural ordering of the films were strongly affected by the degree of polycondensation in the precursor solutions. The formation of siloxane networks containing organosiloxane units was confirmed by 29Si MAS NMR, suggesting that the structure of the inorganic-organic interface can be designed at a molecular level by the functionalities in the alkylmethoxysilanes used. On the other hand, the 29Si NMR spectra of the precursor solutions showed that the monomeric species almost disappeared and that co-condensed oligomers were formed at the initial stages of the reactions. In the cases of mono- and dimethoxysilanes, the ability to form ordered structures depends largely on the co-condensation with tetramethoxysilane in the precursor solutions.

    DOI

    Scopus

    105
    Citation
    (Scopus)

Presentations

  • アルキルモノ-,ジ-,トリ-メトキシシラン-テトラメトキシシラン系からの層状無機-有機名の複合体薄膜の合成

    梅田礼敬, 下嶋敦, 黒田一幸

    日本化学会第79春季年会 

    Presentation date: 2001.03

    Event date:
    2001.03
     
     
  • アルキルモノ-,ジ-,トリ-メトキシシランの自己組織化を利用した無機-有機ハイブリッド薄膜の合成

    梅田礼敬, 下嶋敦, 黒田一幸

    第39回セラミックス基礎科学討論会 

    Presentation date: 2001.01

    Event date:
    2001.01