• 제목/요약/키워드: Self-Assembly

검색결과 690건 처리시간 0.022초

CdTe 나노입자의 자기조립과정을 통한 나노리본 합성 (Conversion of CdTe Nanoparticles into Nanoribbons via Self-Assembly)

  • 오수연;강완규;강정원;김기섭;이흔
    • Korean Chemical Engineering Research
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    • 제50권6호
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    • pp.1082-1085
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    • 2012
  • CdTe 나노입자로부터 형성된 나노리본은 독특한 광학적 특성을 나타낸다. 용액 내 CdTe의 $Te^{2-}$ 이온의 산화는 나노입자에 불규칙적인 결함을 유발하며 이때 여러 층의 나노결정으로 구성된 나노리본을 형성하게 된다. 본 연구에서는 자기조립 된 CdTe 나노입자가 나노리본을 형성하는 과정에서 빛을 조사하였다. 빛은 용액 내 CdTe 나노입자의 표면에 위치한 $Te^{2-}$의 산화를 촉진시키는 촉매 역할을 수행한다. 합성된 3차원 나노리본의 형태와 특성을 투과전자현미경(TEM)으로 조사하였다. TEM 결과 안정제가 완전히 제거된 부분에서 부분적으로 접힌 꼬인 형태의 다결정 나노리본을 관찰할 수 있었다. Photoluminescence (PL) 측정 결과 550 nm에서 544 nm로 나노입자가 나노리본으로 형성될 때 Blue shift 되었음을 확인하였다. 본 연구에서 제안된 새로운 합성법은 나노물질을 합성하는 새로운 대안을 제시한다.

에어로졸 자기조립에 의한 실리카 나노분말의 표면개질 (Surface Modification Silica Nanoparticles by Aerosol Self Assembly)

  • 길대섭;장희동;장한권;조국;김선경;오경준;최진훈
    • 한국재료학회지
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    • 제20권2호
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    • pp.78-81
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    • 2010
  • Surface modification of silica nanoparticles was investigated using an aerosol self assembly. Stearic acid was used as surface treating agent. A two-fluid jet nozzle was employed to generate an aerosol of the colloidal suspension, which contained 20 nm of silica nanoparticles, surface modifier, and ethyl alcohol. Powder properties such as morphology, specific surface area and pore size distribution were analyzed by SEM, BET and BJH methods, respectively. Surface properties of the silica power were analyzed by FT-IR. The OH bond of the $SiO_2$ surface was converted to a C-H bond. It was revealed that the hydrophilic surface changed to a hydrophobic one due to the aerosol self assembly. Morphology of the surface treated powder was nanostructured with lots of pores having an average diameter of around $2\;{\mu}m$. Depending on the stearic acid concentration (0.25 to 1.0 wt%), the pore size distribution of the particles and the degree of hydrophobicity ranged from 1.5 nm to 180 nm and 29.6% to 50.2%, respectively.

SNIPS 공정을 이용한 블록공중합체 분리막의 구조 형성에 관한 연구 (Fabrication of Block Copolymer Membranes via SNIPS Process)

  • 우상훈;김진희;이정현;방준하
    • Korean Chemical Engineering Research
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    • 제55권2호
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    • pp.214-219
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    • 2017
  • 본 연구에서는 블록공중합체의 자기조립(Self-assembly) 성질과 상전이를 통한 비대칭의 다공성 구조를 형성하는 NIPS 기술을 결합한 SNIPS (Self-assembly and non-solvent induced phase separation) 공정을 이용하여 PS-b-P4VP 블록공중합체 분리막을 제조하였다. 기존의 연구는 단순히 원하는 구조 구현에만 집중되었고 SNIPS 공정상의 내재 변수(농도, 증발시간, 용매의 조성, 습도)들에 대한 체계적인 연구는 보고되지 않았다. 본 연구에서는 PS-b-P4VP 와 DMF, 1,4-Dioxane, THF, DI를 이용해 내재 변수의 영향을 정성적으로 분석하였다. 그 결과, 용액의 농도와 휘발성 용매의 비율이 적당하고 습도가 낮은 환경에서 모폴로지가 최적화 되었으며, PS-b-P4VP 분리막은 표면에 잘 구현된 실린더 구조가 형성되었고 75%의 높은 기공도와 약 18%의 표면 기공도를 가지는 것을 확인하였다.

Revesible Switching between Nematic Gel and Isotriopic Fluid Triggered by External Stimuli in Aqueous Self-Assembly of Supramolecular Nanocylinders

  • Ryu, Ja-Hyoung;Lee, Myong-Soo
    • 한국고분자학회:학술대회논문집
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    • 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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    • pp.308-308
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    • 2006
  • We have demonstrated that the cylindrical micelles self-assembled from coil-rod-coil molecules can be interconnected by addition of a small amount of rod-coil-rod molecule as a bridging agent. Subsequently, these dynamic interconnections lead to stiff bundles composed of cylindrical micelles that are responsible for the formation of a reversible nematic gel. The results described here represent a significant example that dynamic bridging of supramolecular cylinders in aqueous solution can provide a useful strategy to construct one-dimensional nematic structure with three dimensional elastic properties.

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Folding of Coordination Polymers into Double-Stranded Helical Organization

  • Kim, Ho-Joong;Lee, Eun-Ji;Lee, Myong-Soo
    • 한국고분자학회:학술대회논문집
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    • 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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    • pp.248-248
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    • 2006
  • The notable feature of the Cu(II) coordination polymer investigated here is its ability to self-assemble into a double-stranded helical structure with regular grooves along the helical axis, through the combination of metal-chloride dimeric interactions and repulsive interactions, as an organizing force. It is also remarkable that the double-stranded helices self-organize into a 2-D columnar structure in both the bulk state and aqueous solution. These results represent a unique example that weak metal-ligand bridging interactions can provide a useful strategy to construct stable double-stranded helical nanotubes.

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무작위 조립법을 이용한 바이오칩의 제작 (Fabrication of Biochip by Hydrophobic Interaction)

  • 최용성;문종대;이경섭
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2006년도 하계학술대회 논문집 Vol.7
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    • pp.404-405
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    • 2006
  • Microarray-based DNA chips provide an architecture for multi-analyte sensing. In this paper, we report a new approach for DNA chip microarray fabrication. Multifunctional DNA chip microarray was made by immobilizing many kinds of biomaterials on transducers (particles). DNA chip microarray was prepared by randomly distributing a mixture of the particles on a chip pattern containing thousands of m-scale sites. The particles occupied a different sites from site to site. The particles were arranged on the chip pattern by the random fluidic self-assembly (RFSA) method, using a hydrophobic interaction for assembly.

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DNA Chip Microarrays를 위한 template로서 소수성 패턴의 제작 (Fabrication of Hydrophobic/Hydrophilic Pattern as a Template for DNA Chip Microaray)

  • 최용성;박대희
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2004년도 추계학술대회 논문집 Vol.17
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    • pp.472-475
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    • 2004
  • Microarray-based DNA chips provide an architecture for multi-analyte sensing. In this paper, we report a new approach for DNA chip microarray fabrication. Multifunctional DNA chip microarray was made by immobilizing many kinds of biomaterials on transducers (particles). DNA chip microarray was prepared by randomly distributing a mixture of the particles on a chip pattern containing thousands of m-scale sites. The particles occupied a different sites from site to site. The particles were arranged on the chip pattern by the random fluidic self-assembly (RFSA) method, using a hydrophobic interaction for assembly.

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다중프로세서 방식의 자동조립시스템을 위한 관리제어 (Supervisory Control for Multi-Processor-Based Automatic Assembly System)

  • 이재혁;유범재;오상록
    • 대한전기학회논문지
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    • 제39권8호
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    • pp.888-897
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    • 1990
  • In this paper, a multi-processor-based supervisory control for automatic assembly system is presented. The proposed supervisory control is organized in terms of C-language and with structured and easily expandable characteristics. Also the controller is designed to possess diagnostic capability including self-diagnosis of processor module. The developed supervisory control has been shown to be very useful via a high speed automatic assembly system with vision capability.

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