• 제목/요약/키워드: 덴드리머

검색결과 35건 처리시간 0.021초

Au (111)기판에 자기조립된 덴드리머 분자의 형태와 전기적 특성에 관한 연구 (Electrical and Morphology Properties of Self-Assembled Dendrimer on Au (111) Substrate)

  • 정경한;신훈규;김정균;권영수
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2003년도 춘계학술대회 논문집 센서 박막재료 반도체 세라믹
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    • pp.120-123
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    • 2003
  • To investigate the characteristics of the single dendrimer molecule, we attempt to measure morphology and electrical properties of the self-assembled dendrimer on Au (111)substrate with SPM(scanning probe microscopy). The same self-assembly procedure was used for two different concentrations, $10{\mu}mol/ml$ and $100{\mu}mol/ml$. The case of lower concentration, we can measure the diameter and the height of the single molecule with the tapping mode AFM image. The imaged single molecules were dome shaped and the average diameter and height were 15.6 nm, 1.2 nm respectively. From these sizes, we can calculate the volume of the single molecule. The volume of the single molecule was estimated about $116nm^3$. However, that of higher concentration, it is difficult to obtain obvious image of the single molecule. To add to, I-V characteristics were investigated using STM, on which the phenomenon of negative differential resistance (NDR)was observed between 0.14 V and 0.24 V reproductively.

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나노구조 덴드리머의 변위특성 (Displacement Properties of Nano Structure Dendrimer)

  • 송진원;이경섭
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2004년도 하계학술대회 논문집 C
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    • pp.1724-1726
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    • 2004
  • Monolayers of lipids on a water surface have attracted much interest as models of biological membranes, but also as precursors of multilayer systems promising many technical applications. Until now, many methodologies have been developed in order to gain a better understand. Photoisomerization in monolayers of a novel azobenzene compound, azobenzene dendrimer, was investigated for the first time by means of the absorption spectrum and Maxwell displacement current (MDC) technique. Dendrimers are well-defined macromolecules exhibiting a tree-like structure, first derived by the cascade molecule approach. According to the absorption spectrum, trans-to-cis conversion ratio was estimated to the third generation of azobenzene dendrimer deposited onto a glass substrate. Temperature-dependent induced charge with trans-cis isomerization was also measured by means of MDC technique.

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광기능성 덴드리머의 계면반응 특성 (Characteristics of Interface Response of Optical Functionalized Dendrimer)

  • 손정호;신훈규;김병상;권영수
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2001년도 추계학술대회 논문집 전기물성,응용부문
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    • pp.121-123
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    • 2001
  • We synthesized dendrimers containing light switchable units such as azobenzene group at the air/water interface. Their chemical structure was verified by using NMR study and UV spectroscopy. We firstly investigated the monolayer behavior and by light irradiation using $\pi$-A isotherm at the air/water interface. As a result, the monolayer of dendrimer with azobenzene group showed the reversible photo-switching behavior by the isomerization of azobenzene group in their periphery. This suggests that optical behavior and morphological change are affected by the functional group and the symmetric chain.

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아조벤젠이 기능화된 덴드리머 유기단분자막의 광학적 성질과 특성 (Characteristics and Optical Properties of the Azobenzene Functionlized Dendrimer in Organic Thin Monolayers)

  • 손정호;윤회찬;김정명;김병상;신훈규;장정수;권영수
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2001년도 하계학술대회 논문집
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    • pp.182-185
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    • 2001
  • The functionlized dendrimer containing 48 azobenzene was synthesized. Many isolated featureless domains were explicitly observed even at the air-water interface. Also, these monolayers were representatively observed, showing the change of surface pressure with irradiation time and wavelength. In AFM images. the larger domains irregularly shaped structures on the top while the smaller ones were free from such defects. In the optical absorption spectra of the LB films by UV irradiation and heat treatment, only photoisomerization of the G4-48Az monolayers was observed, a decrease of absorbance peak without change of the spectral shape. This suggests that optical behavior and morphological change are affected by the functional group and the symmetric chain.

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풀러렌의 성질과 반응 (Reactions and Properties of Fullerene ($C_{60}$))

  • 임충선;홍성규;고원배
    • Elastomers and Composites
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    • 제45권2호
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    • pp.74-79
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    • 2010
  • 논문에서는 풀러렌의 성질, 유기반응, 고분자반응을 설명하였으며, 풀러렌과 고분자의 블렌딩에 대해 소개를 하였다. 또한 다른 화학물질과 풀러렌의 반응성을 기술하였다. 풀러렌의 화학 반응은 가지 사슬 풀러렌 고분자, 주사슬 풀러렌 고분자, 별 모양 풀러렌 고분자, 덴드리머 타입 풀러렌 고분자와 같은 연구에 응용되었다.

기능성 덴드리머 유기단분자막의 분자계면제어 및 분자모폴로지 특성 (Molecular Interfacial Control and Molecular Morphology Properties of Functionalized Dendrimer Organic Monolayers)

  • 신훈규;김두석
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2007년도 하계학술대회 논문집 Vol.8
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    • pp.365-366
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    • 2007
  • The dendrimer has been well known as a promising macromolecules for a building the organized nanostructure, which of the size can be controlled and which of periphery can be terminated by various functionalities. Currently a variety of research is being carried out in the field of dendrimer / polymer characterization, nano-scale atomic manipulation, and supramolecular nanostructure analysis. We investigated monolayer behavior and its characteristics at the air-water interface by LB method. In this report, we will present the interfacial properties of dendrimer monolayers on various conditions such as the surface-pressure, barrier speed and spreading quantity.

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액정성 전방향족 폴리에스테르 (Liquid Crystalline Aromatic Polyesters)

  • 권영완;최동훈;진정일
    • 폴리머
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    • 제29권6호
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    • pp.523-535
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    • 2005
  • 선형 방향족 폴리에스테르는 열방성 액정중합체의 대표적 예로 지금까지 그 구조-액정성 관계가 많이 연구되었다. 본 논문에서는 지난 4반세기 동안 본 연구진이 행한 연구결과를 중심으로 액정성 전방향족 폴리에스테르의 열적특성 및 액정성을 그 화학구조와 관련지어 논의한다. 특히 미세화학구조의 변경이 어떻게 액정성에 영향을 주는가에 논의의 초점을 두었다. 특히 선형구조에서 크게 벗어나는 복합형 액정성 폴리에스테르 및 액정성 고차가지구조 폴리에스테르도 조감하였다. 고차가지구조 고분자는 덴드리머와 관련하여 많은 관심을 끌고 있다. 이 고분자들의 합성법도 말미에 소개하고 있다.

G4-48PyA 덴드리머 박막의 금속이온 착체 효과 (Effect of Complex with Metal Ions of G4-48PyA Dendrimer Thin Films)

  • 정상범;유승엽;박은미;김정균;박재철;권영수
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2001년도 추계학술대회 논문집 전기물성,응용부문
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    • pp.131-133
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    • 2001
  • Dendrimers represent a new class of synthetic macromolecules characterized by a regularly branched treelike structure. Peculiar features of the dendritic geometry are the large number of end groups as well as the shape persistence in higher generations, approaching spherical geometry. And one of the most peculiar characteristics of dendritic macromolecules is their controlled molecular structure and orientation, which means that they have a practical application in achieving a highly organized molecular arrangement. We attempted to fabricate a G4-48PyA dendrimer LB films containing 48 pyridinealdoxime functional end group that could form a complex structure with metal ions. Also, we investigated the surface activity of dendrimer films at air-water interface. And we have studied the electrical properties of the ultra-thin dendrimer LB films. The electrical properties of the ultra-thin dendrimer LB films were investigated by studying the current-voltage characteristics of metal/dendrimer LB films/metal (MIM) structure. And rectifying behavior of the devices was occurred in applied field.

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