• 제목/요약/키워드: Basic organic chemistry

검색결과 157건 처리시간 0.026초

A New Chromogenic Water Sensing System Utilizing Deprotonation and Protonation of Anion Receptor

  • Kim, Young-Hee;Han, Yeon-Kun;Kang, Jong-Min
    • Bulletin of the Korean Chemical Society
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    • 제32권12호
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    • pp.4244-4246
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    • 2011
  • A simple chromogenic system based on 1-fluoride was developed to determine water content in organic solvent. This system utilized deprotonation and protonation of the anion receptor 1. The water content evaluated from this system gave close value to the real water content in the range of 0 to 0.35% in acetonitrile and 0.2 to 0.5% in DMSO. Therefore, protonation and deprotonation phenomenon from the anion receptor by basic anion could be promising method for water sensing system.

유기 전기 발광소자의 원리와 연구동향 (Research Trends in Organic Light Emitting Diode)

  • 신환규;김승호;이재현;이하윤;정효철;박종욱
    • 공업화학
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    • 제26권4호
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    • pp.381-388
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    • 2015
  • 유기 발광 다이오드(OLED)는 학문 및 산업분야에서 많은 관심을 받아 왔으며, 소자가 갖는 우수한 장점을 바탕으로 모바일 디스플레이뿐만 아니라 대면적 TV, 차세대 굴곡형 디스플레이의 적용이 활발하게 진행되고 있다. 또한 OLED 재료의 연구와 소자제작 기술의 응용 연구 범위를 넓혀가고 있다. 본 논문에서는 이러한 OLED에 대한 기본적인 소자구성 및 원리를 설명하고, 다양한 화학구조를 응용한 OLED 재료를 각각의 용도에 맞게 분류 정리하였다. 이러한 OLED 기술의 개념과 재료의 특성을 체계적으로 분류함으로써 새로운 발광 재료를 연구하고 개발함에 있어서 많은 도움이 되리라고 생각한다.

Alq$_3-based$ Organic Light-Emitting Devices with Al/NaF cathodes: Performance Enhancement and Interface Electronic Structures

  • Park, Y.;Lee, J.;Kim, D.Y.;Chu, H.Y.;Lee, H.;Do, L.M.
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2003년도 International Meeting on Information Display
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    • pp.25-27
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    • 2003
  • The device characteristics and the interface electronic structures of organic light-emitting devices based on /tris-(8-hydroxyquinoline)aluminum ($Alq_3$) were investigated with Al/NaF cathode. The Al/NaF cathode greatly improved the performance of the device over the Al-only cathode. A series of photoelectron spectroscopy studies on cathode structures including Al/LiF and $Al/CaF_2$ revealed that the performance enhancement originated mainly from the HOMO peak shift upon the fluoride deposition rather than the formation of the gap states

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Photopolymerization of Vinyl Monomers Using Organic Initiators

  • Kim, Myoung-Hee;Lee, Jun;Cha, Hyo Chang;Ham, Heui-Suk;Woo, Hee-Gweon
    • 통합자연과학논문집
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    • 제2권1호
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    • pp.1-12
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    • 2009
  • This miniaccount presents the selective examples of our recent discoveries in the photopolymerization of vinyl monomers using the organic initiators such as hydrosilanes, poly(hydroarylsilane)s, benzoin silyl ethers, and thianthrene cation radical. In the photopolymerization of vinyl monomers with silanes polysilanes, while the polymerization yields and polymer molecular weights of the poly(MMA)s containing the silyl moieties decreased, the TGA residue yields and intensities of SiH stretching IR bands increased as the mole ratio of the silanes over MMA increased. The hydroarylsilane and poly(hydroarylsilane) seemed to influence strongly on the photopolymerizaiton of olefinic monomers as both chain initiation and chain transfer agents. For the photohomopolymerization and photocopolymerization of MA and AA, the similar trends were observed. Benzoin silyl ethers and thianthrene cation radical also exhibit the photoinitiating ability in the photopolymerization of MMA.

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Biomimetic Catalysis in Ionic Liquids: Markedly Enhanced Enantioselectivity in Amino Acid-Catalyzed Directed Asymmetric Aldol Reactions

  • Yun, Suk-Jin;Lee, Jae Kwan
    • 통합자연과학논문집
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    • 제8권2호
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    • pp.107-110
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    • 2015
  • Amino acid-catalyzed directed asymmetric aldol reactions showed enhanced enantioselectivity when conducted in ionic liquids. Optically active products were afforded in better yields (up to 23% higher) and enantiomeric excess (up to 21% higher) in ionic liquids than in conventional organic solvents.

Synthesis and Nonlinear Optical Properties of Novel T-type Polyester Containing Thiophene with Enhanced Thermal Stability

  • No, Hyo-Jin;Cho, You-Jin;Lee, Ju-Yeon
    • Bulletin of the Korean Chemical Society
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    • 제31권2호
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    • pp.429-434
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    • 2010
  • A novel T-type polyester 7 containing 1-(2,5-dioxyphenyl)-2-{5-(1,2,2-tricyanovinyl)-2-thienyl}ethenes as nonlinear optical (NLO) chromophores, which are part of the polymer backbone, was prepared and characterized. Polyester 7 is soluble in common organic solvents such as dimethylsulfoxide and N,N-dimethylformamide. It showed a thermal stability up to $300^{\circ}C$ in thermogravimetric analysis thermogram and the glass-transition temperature ($T_g$) obtained from differential scanning calorimetry thermogram was around $113^{\circ}C$. The second harmonic generation (SHG) coefficient ($d_{33}$) of poled polymer films at 1,560 nm fundamental wavelength was around 1.85 pm/V. The dipole alignment exhibits a greater thermal stability even at $10^{\circ}C$ higher than $T_g$, and there is no SHG decay below $125^{\circ}C$ due to the partial mainchain character of the polymer structure, which is acceptable for nonlinear optical device applications.

Preparation of Novel T-type Polyurethanes with High Thermal Stability of Second Harmonic Generation and Their Nonlinear Optical Properties

  • Jang, Han-Na;Lee, Ga-Young;Lee, Ju-Yeon
    • Bulletin of the Korean Chemical Society
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    • 제29권4호
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    • pp.811-816
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    • 2008
  • 2,5-Di-(2'-hydroxyethoxy)benzylidenemalononitrile (3) was prepared and polymerized with 2,4-toluenediisocyanate and 3,3'-dimethoxy-4,4'-biphenylenediisocyanate to yield novel T-type polyurethanes 4 and 5 containing 2,5-dioxybenzylidenemalononitrile, nonlinear optical (NLO)-chromophores as part of the polymer backbones. Polyurethanes 4 and 5 were soluble in common organic solvents such as acetone and N,Ndimethylformamide and showed a thermal stability up to $250{^{\circ}C}$ with glass-transition temperatures ($T_g$) in the range $119-146{^{\circ}C}$. The second harmonic generation (SHG) coefficients ($d_{33}$) of poled polymer films at 1064 nm fundamental wavelength were around $5.82{\times}10^{-9}$ esu. The dipole alignment exhibited high thermal stability up to $T_g$, and there was no SHG decay below $140{^{\circ}C}$ due to the partial main-chain character of the polymer structure, which was acceptable for nonlinear optical device applications.

Synthesis of Novel Y-type Nonlinear Optical Polyester with Enhanced Thermal Stability of Second Harmonic Generation for Electro-Optic Applications

  • Cho, You-Jin;Lee, Ju-Suk;Lee, Ju-Yeon
    • Bulletin of the Korean Chemical Society
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    • 제31권6호
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    • pp.1509-1514
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    • 2010
  • Methyl 3,4-di-(2'-hydroxyethoxy)benzylidenecyanoacetate (3) was prepared and condensed with terephthaloyl chloride to yield novel Y-type polyester (4) containing 3,4-dioxybenzylidenecyanoacetate groups as NLO-chromophores, which constituted parts of the polymer main chains. The resulting polymer 4 is soluble in common organic solvents such as acetone and N,N-dimethylformamide. Polymer 4 shows thermal stability up to $280^{\circ}C$ in thermogravimetric analysis with glass-transition temperature obtained from differential scanning calorimetry near $105^{\circ}C$. The second harmonic generation (SHG) coefficient ($d_{33}$) of poled polymer films at the 1064 nm fundamental wavelength is around 2.42 pm/V. The dipole alignment exhibits high thermal stability up to near $T_g$, and there is no SHG decay below $100^{\circ}C$ due to the partial main-chain character of polymer structure, which is acceptable for NLO device applications.