• 제목/요약/키워드: UV-spectrum

검색결과 557건 처리시간 0.03초

유기 초박막의 가스 특성에 관한 연구 ($NO_2$ Gas Detection Characteristics of Langmuir-Blodgett Films layered with Dilithium phthalocyanine($Li_2Pc$))

  • 조형근;유병호;김형석;김태완;김정수
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1994년도 하계학술대회 논문집 C
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    • pp.1298-1300
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    • 1994
  • An ability of $NO_2$ gas detection has been investigated using dilithium phthalocyanine($Li_2Pc$) Langmuir-Blodgett (LB) films. It is a well-known gas sensitive material and has been manufactured under a surface pressure of 30mN/m. A status of deposited films was confirmed by UV-visible absorption spectrum, ellipsometry measurements and current-voltage characteristics. Gas-detection characteristics of the films were studied through an electrical conductivity, response time, recovery time, and reproducibility under 200 ppm of $NO_2$ gases.

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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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자외선 파장에 따른 FRP의 표면 열화특성 및 열화메커니즘에 관한 연구 (A Study on the Characteristics of Surface Degradation & Degradation-Mechanism in UV Treated FRP)

  • 이백수;임경범;나동근;정무영;정의남;유도현;이덕출
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1998년도 추계학술대회 논문집 학회본부 C
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    • pp.813-815
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    • 1998
  • In order to analyse the degradation process of epoxy/glass fiber for outdoor condition, FRP laminate was exposed to the wavelength of ultraviolet rays and evaluated by comparing contact angle, surface resistivity, surface potential decay, and ESCA spectrum respectively. Finally, We can conclude that the degradation phenomena on the surface of epoxy composites are dominated by the induction of ester and carboxyl groups.

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Synthesis and Chiro-Optical Properties of Water Processable Conducting Poly(diphenylamine) Nanocomposites

  • Showkat, Ali Md;Lee, Kwang-Pill;Gopalan, Anantha Iyengar;Kim, Sang-Ho
    • Macromolecular Research
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    • 제15권6호
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    • pp.575-580
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    • 2007
  • Water-soluble, chiral conducting, poly(diphenylamine) (PDPA) nanocomposites were synthesized by chemical oxidative polymerization of diphenylamine in the presence of poly(acrylic acid) (PAA) as a template and camphor sulphonic acid (CSA) as the chiral inductor, Composites were formed as stable aqueous dispersions under different experimental conditions, such as DPA to PAA molar ratios, PAA molecular weight, etc. Circular dichroism(CD) spectra of the composites indicated the induction of chirality to PDPA. Compared to simple chiral PANI, the PDPA/PAA/CSA nanocomposites showed a different Cotton effect. The appearance of a CD band in the composite was complimentary to the bisignate, exciton-coupled band in the UV-Visible spectrum. FTIR spectra indicated the intimate mixing of PDPA and PAA.

Hybrid Nanocomposites of Palladium Nanoparticles Having POSS and MWNTs via Ionic Interactions

  • Jeon, Jong-Hwan;Lim, Jung-Hyurk;Kim, Kyung-Min
    • Macromolecular Research
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    • 제17권12호
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    • pp.987-994
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    • 2009
  • Palladium nanoparticles having cubic silsesquioxanes (POSS) (Pd-POSS) were produced by the reaction of palladium (II) acetate and octa(3-aminopropyl)octasilsesquioxane octahydrochloride (POSS-${NH_3}^+$ in methanol at room temperature. Functionalized multiwalled carbon nanotubes (MWNT-COOH) were prepared by acid treatment of pristine MWNTs. The hybrid nanocomposites of Pd-POSS and MWNT-COOH (Pd-MWNT nanocomposites) were synthesized by self-assembly method via ionic interaction between positively charged Pd-POSS and negatively charged MWNT-$COO^-$. The spherical aggregates of Pd-POSS with a diameter of 40-60 urn were well attached to the surfaces of MWNT-COOH on Silicon wafer. The composition, structure, and surface morphology of Pd-MWNT nanocomposites were studied by UV-vis spectrophotometer, energy dispersive spectrum (EDX), scanning electron microscopy (SEM), and atomic force microscope (AFM).

Fluorescence Micropatterning Based on the Polymeric Photobase Generator Containing Oxime-Urethane Groups by Dansylation

  • Choi, Won San;Kim, Hak Soo;Chae, Kyu Ho
    • Rapid Communication in Photoscience
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    • 제2권1호
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    • pp.24-27
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    • 2013
  • A polymeric photobase generator containing oxime-urethane groups is applied to a fluorescence micropatterning material. Polymer bearing oxime-urethane groups was prepared by copolymerization of methyl methacrylate with methacryloyloxyethyl benzophenoneoxime urethane (MBU). The reaction of amino groups in the irradiated copolymer film with dansyl chloride (Dns-Cl) was monitored by using UV absorption, IR absorption and fluorescence spectroscopy. The fluorescence spectrum of the Dns-Cl-treated irradiated copolymer film shows a strong fluorescence with a fluorescence maximum wavelength at 510 nm. A blue fluorescent micropattern with a line width of $2{\sim}3{\mu}m$ was obtained. Treatment of the irradiated copolymer film with Dns-Cl and rhodamine B mixture led to the formation of green, red, and orange-colored fluorescence micropatterns. Thus, various colored micropatterns on a single polymer film can be obtained by selective excitation of each dye molecules.

Synthesis and properties of organic light-emitting diodes using BECCIP material

  • 박종욱;이원재;김태완;박종욱;김태완;강도열
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2000년도 제2회 학술대회 논문집 일렉트렛트 및 응용기술전문연구회
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    • pp.56-58
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    • 2000
  • We have synthesized the new blue electroluminescent material, Bis(3-N-ethylcarbazolyl)cyanoisophthalidene(BECCIP), and characterized its properties by UV/visible absorption, photoluminescent(PL) and electroluminecent(EL) spectrum. This material is well vacuum-deposited for thin film and has dear surfaced thin film property. The BECCIP shows blue PL and EL spectra at around at 485nm.

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지방산 Langmuir-Bledgett막의 광이성화에 관한 연구 (A Study on the Photoisomerization of Langmuir-Bledgett Films of Fatty Acid)

  • 박근호
    • 한국응용과학기술학회지
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    • 제16권3호
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    • pp.193-198
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    • 1999
  • Maxwell displacement current(MDC) measuring technique has been applied on the study of monolayers of fatty acid. The displacement current was generated from monolayers on the water surface by monolayer compression and expansion. Displacement current was generated when the area per molecule was about $130{\AA}^2$. MDCs were investigated in connection with monolayer compression cycles. It was found that the current pulses were generated over the entire range of molecular area, and the maximum of MDC appeared at the molecular area just before the initial rise of surface pressure in compression cycles. We investigated the change in absorption spectra of the fatty acid(8A5H) monolayer LB film due to cis-trans photoisomerization. It was found that the absorption spectrum of the 8A5H LB film was induce to photoisomerization by alternate irradiation with UV and visible light irradiation.

Fabrication of Organic-Inorganic Hybrid Thin Film by Molecular Layer Deposition

  • 한규석;김수환;한기복;성명모
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2010년도 제39회 하계학술대회 초록집
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    • pp.251-251
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    • 2010
  • Organic-inorganic hybrid materials have attracted because of its combined properties, such as flexibility and high electrical performance. In addition, the hybrid materials are expected to have synergic effect which are not shown in just one component. Here, we fabricated organic-inorganic hybrid thin film. Organic-inorganic hybrid thin film have been deposited from diethyl zinc and 1, 2, 4-trihydroxybenzene (THB) by molecular layer deposition (MLD). UV-VIS, Using Infrared spectrum and X-ray photoelectron spectroscopy confirm that Zinc and THB hybrid film (ZnTHB) consist of Zn-O and THB - oxide units and the micro structure and composition of hybrid film. hat the sequential surface reactions of diethyl zinc and ethylene glycol are sufficiently self-limiting and saturating to enable well-controlled MLD growth. Transmission electron microscopy image shows lamination growth of ZnTHB film according to cycle.

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Clostridium sp.가 생산하는 항생물질 KG-1167A와 KG-1167B의 정제 및 특성 (Purification and Characterization of Antibiotics KG-1167A & KG-1167B Produced by Clostridium sp.)

  • 홍수형;류재호;하지홍;박용복
    • 한국미생물·생명공학회지
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    • 제18권3호
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    • pp.286-291
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    • 1990
  • 순수분리된 2,200여주의 혐기성 세균으로부터 선별된 Clostridium sp. KH-1167은 그람양성 및 음성균에 대하여 재현성있는 항균활성을 나타내는 무질을 생산하였다. Solvent extraction, silica gel column chromatography에 의하여 배양액으로부터 항생물질 KG-1167A와 KG-1167B를 부분정제 하였다. 이들은 pH4-11의 범위에서는 비교적 안정하였으나, 온도에 대해서는 $50^{\circ}C$정도에서부터 점차 불안정해지는 것을 알 수 있었다.

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