• Title/Summary/Keyword: Air-Water Interface

Search Result 282, Processing Time 0.03 seconds

A Study on the Electrical Properties of DLPC LB films (DLPC LB박막의 전계자격 응답특성)

  • Cho, S.Y.;Oh, J.H.;Lee, K.S.;Kim, H.J.;Kim, H.G.;Kim, B.C.
    • Proceedings of the KIEE Conference
    • /
    • 1998.11c
    • /
    • pp.810-812
    • /
    • 1998
  • We studied on the $\pi$-A isotherm of the L-$\alpha$-DLPC was measured at the air-water interface varying with the compressing speed and amounts of solutions for spreading. The molecular arrangement of deposited films were evaluated by measuring the absorption with the UVspectrometer. We made structures of metal(Au)/organic thin films (L-$\alpha$-DLPC)/Metal(Au), the number of accumulated layers are 3. And I-V characteristic of the device examined.

  • PDF

Fabrication of Wafer-scale Polystyrene (2+1) Dimensional Photonic Crystal Multilayers Via the Layer-by-layer Scooping Transfer Technique

  • Do, Yeong-Rak;O, Jeong-Rok;Lee, Gyeong-Nam
    • Proceedings of the Materials Research Society of Korea Conference
    • /
    • 2011.05a
    • /
    • pp.11.1-11.1
    • /
    • 2011
  • We have developed a simple synthetic method for fabricating a wafer-scale colloidal crystal film of 2D crystals in a 1D stack based on a combination of two simple processes : the self-assembly of polystyrene (PS) nanospheres at the water-air interface and the layer-by-layer (LbL) scooping transfer technique. The main advantage of this approach is that it allows excellent control of the thickness (at a layer level) of the crystals and the formation of a vertical crack-free layer over a wafer-scale (4 inch). We investigate the optical and morphological properties of the PhC multilayers fabricated using various mono-sized colloidal crystals (250, 300, 350, 420, 580, 720, and 850 nm), and mixed binary colloidal crystals (300/350 and 250/350 nm).

  • PDF

Soft-Lithographic Fabrication of Ni Nanodots Using Self-Assembled Surface Micelles

  • Seo, Young-Soo;Lee, Jung-Soo;Lee, Kyung-Il;Kim, Tae-Wan
    • Journal of Magnetics
    • /
    • v.13 no.2
    • /
    • pp.53-56
    • /
    • 2008
  • This study proposes a simple nano-patterning process for the fabrication of magnetic nanodot arrays on a large area substrate. Ni nanodots were fabricated on a large area (4 inches in diameter) Si substrate using the soft lithographic technique using self-assembled surface micelles of Polystyrene-block-Poly(methyl methacrylate) (PS-b-PMMA) diblock copolymer formed at the air/water interface as a mask. The hexagonal array of micelles was successfully transferred to a Ni thin film on a Si substrate using the Langmuir-Blodgett technique. After ion-mill dry etching, a magnetic Ni nanodot array with a regular hexagon array structure was obtained. The Ni nanodot array showed in-plane easy axis magnetization and typical soft magnetic properties.

Development of a Method for Separating the Faceplate of used CRT (환경친화적 폐 CRT 분리 시스템 개발)

  • 이화조;임병훈;허성필
    • Proceedings of the Korean Society of Precision Engineering Conference
    • /
    • 2003.06a
    • /
    • pp.848-851
    • /
    • 2003
  • In this paper, a separating system for used CRT recycling is presented. Depend on manufacturer CRTs has small differences in dimension for the same model, but the dimensions of the panel are nearly same. To simplifying configuration of the system, we developed CRT fixing pallets for every model of CRT. The height of cutting position for every model of CRT will be same. The cutting machine has two rotating arm and use metal-bond type diamond cutting wheel. Instead of water, two vortex tube type air-coolers are used for the cooling of cutter. Workers in recycling factory are generally old people. Therefore, control program should be easy to use and operate. Thus we developed GUI with very simple interface.

  • PDF

Optical and electrical properties of the PAAS L films and LB films observed by BAM (BAM으로 관측한 PAAS L막의 특성 및 LB막의 광학적, 전기적 특성에 관한 연구)

  • Lee, Seung-Yop;Kim, Tae-Wan;Kang, Dou-Yol
    • Proceedings of the KIEE Conference
    • /
    • 1996.07c
    • /
    • pp.1725-1727
    • /
    • 1996
  • Brewster angle microscopy(BAM) makes it possible to measure domains of Langmuir films. Especially, formation and phase transition of the PAAS Langmuir monolayers from a gas phase to a solid phase at the air-water interface were observed by the use of BAM. And also we observed the comparative images of films deposited at each phase. The UV/visible absorption spectra of this films showed molecular intensity and aggregation at each state. The electrical properties of this material were measured by current-voltage(I-V) characteristics.

  • PDF

Study on morphology of silsesquioxane based polymer LB films by using AFM (AFM을 이용한 Silsesquioxane based polymer의 LB막 모폴로지 관찰)

  • Lee, Ji-Yoon;Yang, Chang-Heon;Kim, Chung-Kyun;Park, Jae-Chul;Kwon, Young-Soo
    • Proceedings of the KIEE Conference
    • /
    • 2008.07a
    • /
    • pp.1293-1294
    • /
    • 2008
  • The Langmuir-Blodgett (LB) method has been one of the most suitable techniques for fabricating organic thin films with well-controlled structures, compositions and thickness at the molecular level. We investigated the surface activity of dendrimer films at air-water interface by ${\pi}$-A isotherm. Also, we attempted to fabricate a 1G(4,3)-chloride dendrimer LB films. And their surface morphologies were observed by atomic force microscopy (AFM).

  • PDF

SIMULATION OF FREE SURFACE FLOW OVER TRAPEZOIDAL OBSTACLE WITH LATTICE BOLTZMANN METHOD (격자볼츠만법을 이용한 장애물 월반 자유수면 시뮬레이션)

  • Korkmaz, Emrah;Jung, Rho-Taek
    • Journal of computational fluids engineering
    • /
    • v.19 no.2
    • /
    • pp.79-85
    • /
    • 2014
  • An air-water free surface flow simulation by using the Lattice Boltzmann Method(LBM) has not been studied a lot compared with the done by the Navier-Stoke equation. This paper shows the LBM is as one of the application tools for the free surface movement over an obstacle. The Mezo scaled application tool has been developed with two dimensional and nine discretized velocity direction using conventional lattice Bhatnagar-Gross-Krook model. Boundary conditions of a halfway-based for solid wall and a kinematic-based for interface are adopted. A validation case with a trapezoidal shape bump to make a comparison between freesurface movements from computational results and experimental ones was described with grid size dependency.

A length dependance of monolayer films of long-chain fatty acids (장쇄지방산의 길이에 따른 단분자막의 특성 변화)

  • 구창권;김무군;송경호;박태곤
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 1996.05a
    • /
    • pp.38-42
    • /
    • 1996
  • The pressure-area isotherm of monolayer at the air-water interface were obtained and the LB films were fabricated onto a quartz slides and quartz crystal by conventional Langmuir-Blodggett(LB) method. The UV absorption spectra of Langmuir-Blodggett(LB) film on quartz slides and spectrum of monolayer formed on quartz crystal have been measured. The photoisomerization of the long-chain fatty avid containing azobenzene were obtained by the application of UV and visible light. The reversibility of photoisomerization were more clear difference when the number of C$\_$n/ increased. At the pressure-area isotherms, the value of surface pressure increment were decreased when the number of C$\_$n/ increased, A surface pressure of 20mN/m was obtained as a proper one for a film deposition. The photoisomerization at LB films were also obtained by application of UV and visible light. So the LB film of long-chain fatty acid containing azobenzene has possibility to being applies to functional molecular devices such as photomemory and light switching.

  • PDF

Surface-Enhanced Raman Spectroscopic Studies of Oriented Monolayers on Electrode Surfaces

  • Yoon, Wan-Shik;Im, Jung-Hyuk;Kim, Jae-Ho
    • Analytical Science and Technology
    • /
    • v.8 no.4
    • /
    • pp.699-705
    • /
    • 1995
  • Monolayers of hypericin, a photodynamic polycyclic quinoidal compound, were prepared at the air-water interface, and were transferred to metal substrates to form Langmuir-Blodgett (LB) monolayers. The structural characteristics of hypericin LB monolayers and self-assembled (SA) monolayers were investigated using surface-enhanced resonance Raman scattering (SERRS) spectroscopy. Both the spectroscopic data and the surface pressure - area (${\pi}-A$) isotherms suggest that hypericin forms ${\pi}-{\pi}$ aggregates that orient vertically to the subphase surface. Whereas the ordering and orientation of control was less effective in SA monolayers, a higher structural regularity was attained in LB systems. The effect of subphase on the structural integrity of the monolayer was also investigated.

  • PDF

Bioinspired Nanoengineering of Multifunctional Superhydrophobic Surfaces

  • Choi, Chang-Hwan
    • Proceedings of the Korean Institute of Surface Engineering Conference
    • /
    • 2015.11a
    • /
    • pp.102-133
    • /
    • 2015
  • Nature, such as plants, insects, and marine animals, uses micro/nano-textured surfaces in their components (e.g., leaves, wings, eyes, legs, and skins) for multiple purposes, such as water-repellency, anti-adhesiveness, and self-cleanness. Such multifunctional surface properties are attributed to three-dimensional surface structures with modulated surface wettability. Especially, hydrophobic surface structures create a composite interface with liquid by retaining air between the structures, minimizing the contact area with liquid. Such non-wetting surface property, so-called superhydrophobicity, can offer numerous application potentials, such as hydrodynamic drag reduction, anti-biofouling, anti-corrosion, anti-fogging, anti-frosting, and anti-icing. Over the last couple of decades, we have witnessed a significant advancement in the understanding of surface superhydrophobicity as well as the design, fabrication, and applications of superhydrophobic coatings/surfaces/materials. In this talk, the designs, fabrications, and applications of superhydrophobic surfaces for multifunctionalities will be presented, including hydrodynamic friction reduction, anti-biofouling, anti-corrosion, and anti-icing.

  • PDF