• Title/Summary/Keyword: photo-journal

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Chemical Vapor Deposition Polymerization of Poly(arylenevinylene)s and Applications to Nanoscience

  • Joo, Sung-Hoon;Lee, Chun-Young;Kim, Kyung-kon;Lee, Ki-Ryong;Jin, Jung-Il
    • Bulletin of the Korean Chemical Society
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    • v.27 no.2
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    • pp.169-184
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    • 2006
  • A review is made on the chemical vapor deposition polymerization (CVDP) of insoluble and infusible poly(arylenevinylene)s and its applications to nanoscience. Poly(p-phenylenevinylene) (PPV), poly(naphthylenevinylene)s, poly(2,5-thinenylenevinylene) (PTV), and other homologous polymers containing oligothiophenes could be prepared by the CVDP method in the form of films, tubes, and fibers of nano dimensions. They would be readily converted to graphitic carbons of different structures by thermal treatment. Field emission FE) of carbonized PPV nanotubes, photoconductivity of carbonized PPV/PPV bilayer nanotubes and nanofilms also were studied.

Study on the Curing Properties of Photo-curable Acrylate Resins (광경화성 아크릴 수지의 경화특성에 관한 연구)

  • Kim, Sung-Hyun;Chang, Hyun-Suk;Park, Sun-Hee;Song, Ki-Gook
    • Polymer(Korea)
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    • v.34 no.5
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    • pp.469-473
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    • 2010
  • The curing mechanism and characteristics of UV curable acrylate resins were studied using Photo-DSC, FTIR, and Raman spectroscopy. Effects of chemical structures of acrylate, numbers of functional group, and UV intensity on curing kinetics were investigated with Photo-DSC. FTIR and Raman spectroscopy has been used to understand curing mechanisms and reaction conversion. In order to investigate the effect of oxygen on the photo-curing reaction, the curing process was compared between the acrylate and thiol-ene resins. The reaction conversion was found to be less than 80% for acrylate resins. The photo-curing reaction of the acrylate resin could not proceed to the end because of oxygen which acts as a reaction inhibitor while the thiol-ene resin was hardly affected from oxygen during the curing process.

Monitoring photo-polymerization reaction using near-IR spectroscopic technique (Near-IR 분광법을 이용한 광 경화 중합반응 관찰)

  • Chung, Soo-Chung;Hong, Jin-Who;Yu, Jeong-A
    • Analytical Science and Technology
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    • v.15 no.4
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    • pp.341-345
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    • 2002
  • The extent of UV-curing photo-polymerization reaction was monitored by near-IR spectroscopic method. Acrylates containing quaternary ammonium salts and Darocur 1173 were used as reactive monomer and a photo initiator, respectively. The extent of photo-polymerization reaction was obtained from the conversion ratio of acrylate double bond calculated from the intensities of measured bands at 1615 nm and at 2105 nm. Near-IR spectroscopic methods can be an useful tool for the monitoring of the progress of photo-polymerization.

Application of GIS Technique for Fire Drill in Hillside Area

  • Chung Yeong-Jin
    • Spatial Information Research
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    • v.12 no.4 s.31
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    • pp.321-328
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    • 2004
  • The purpose of this study is to describe 3-Dimensional technique to obtain spatial information automatically using PhotoModeler Pro. PhotoModeler Pro is excellent software with the three-dimensional measurement function used by a personal computer using Windows operating system However, it is not sufficient to carry out the automatic matching work with two stereo images. This is very large neck as a 3-D measurement software. In this study, the automatic stereo matching work using the self-making program and DDE interface within PhotoModeler Pro was tried. The experiment field is the hillside and stair zone of Tateyama region, Nagasaki City. The results of automatic stereo matching work were very good with $100\%$ hitting ratio of target.

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Diffraction Behaviors of New Photopolymers Containing the Dendritic Molecule

  • Kim Go Woon;Jun Woong Gi;Lee Sang Kyu;Cho Min Ju;Jin Jung-Il;Choi Dong Hoon
    • Macromolecular Research
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    • v.13 no.6
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    • pp.477-482
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    • 2005
  • Photopolymers are attractive materials for holographic 3-D data storage because of their high photosensitivity and large refractive index modulation. We synthesized the six-armed dendrimer for fabricating the new photopolymer. It was prepared using the initiating mixture of hexaarylbiimidazole (HABI), mercapto-benzoxazole (MOBZ), and 2,6-bis(4-diethylaminobenzylidene)cyclopentanone (DEAW), which is sensitive to 514 nm wavelength. The holographic gratings were fabricated successfully in these photopolymer samples by conventional optical interference method. We investigated the effect of dendrimer, either as a binder or as a plasticizer in the cellulose acetate butyrate (CAB), on the diffraction behavior. The addition of only 1 wt$\%$ of dendrimer-I into the CAB significantly increased the diffraction efficiency. The sample doped with dendrimer showed around 80-83$\%$ of the diffraction efficiency.

Comparison and Analysis of Features between Aerial Photo Image and Satellite Image (항공사진 영상과 위성 영상간의 지형지물 비교.분석)

  • 김감래;김재연
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.21 no.1
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    • pp.1-7
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    • 2003
  • Practical use is increasing on the aerial ortho image recently, and much researches for geographic information system build that use high resolution satellite image cause this are progressing. Also many researches that use KOMPSAT-1 satellite image of resolution 6.6m are performing in these days, estimation for between aerial photo and satellite image is needed. In this treatise scanned image of aerial photo, using aerial photo resampling image of resolution equal with KOMPSAT-1 image using aerial photo, and KOMPSAT-1 satellite image use for experimental image making each orthoimage, classified feature for estimate. We evaluated to what level that an separation item could be able to estimate in each orthoimage. As result of estimation analysis, In the classified feature in aerial photo orthoimage with aerial photo resampling image orthoimage is about 61%, KOMPSAT-1 satellite image orthoimage is almost 41% could estimated. Through this investigation estimate, KOMPSAT-1 satellite sue to map updating, geographic information og non-approach area and environment inspect.

Decomposition of Gas-Phase Benzene on TiO2 Coated Alumina Balls by Photocatalytic Reaction (이산화티탄이 코팅된 알루미나 볼에서 광촉매 반응에 의한 기상벤젠의 분해)

  • Lee Nam-Hee;Jung Sang-Chul;Sun Il-Sik;Cho Duk-Ho;Shin Seung-han;Kim Sun-Jae
    • Korean Journal of Materials Research
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    • v.14 no.6
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    • pp.407-412
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    • 2004
  • Photo decomposition of gas phase benzene by $TiO_2$ thin films chemically deposited on alumina balls were investigated under UV irradiation. Photo decomposition rates were measured in real time during the reaction using a photo ionization detector, which ionizes C-H bonding of benzene molecules and then converts into volatile organic compounds (VOCs) concentrations. From the measuring results, the VOCs concentration increased instantly when IN irradiated because C-H bonds of benzene molecules strongly absorbed on the surface of $TiO_2$ films before the IN irradiation was destroyed by photo decomposition. After that, the VOCs concentration decreased with increasing surface area of $TiO_2$ and reaction time under the IN irradiation. At the optimal conditions for the photo decomposition of gas phase benzene, the reaction rate of the photo decomposition for high concentrations (over 60 ppm) was slow but that of relatively low concentration (under 60 ppm) was fast, due to limited surface area of $TiO_2$ thin films for the reaction. Thus, it is concluded that the photo decomposition rate was mainly affected by the surface area of $TiO_2$ or absorption reaction.

A Study on the degradation of Lindane in water by a Photo-Fenton process and a UV/$H_2O_2$ process (Photo-Fenton 공정과 UV/$H_2O_2$ 공정을 이용한 Lindane의 분해특성 비교 연구)

  • Lee, Ju-Hyun;Choi, Hye-Min;Kim, Il-Kyu
    • Journal of Korean Society of Water and Wastewater
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    • v.24 no.1
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    • pp.109-117
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    • 2010
  • In the present study, the degradation characteristics of Lindane by Advanced Oxidation Processes(UV/$H_2O_2$, Photo-Fenton process) were studied. The degradation efficiency of Lindane in aqueous solution was investigated at various initial pH values, Fenton's reagent concentrations and initial concentrations of Lindane. GC-ECD was used to analyze lindane. Lindane has not been degraded without application of AOPs over two hours. But, approximately 5% of lindane was degraded with UV or $H_2O_2$ alone. Lindane with UV/$H_2O_2$ process showed approximately 7% higher removal efficiency than $H_2O_2$ process. In the UV/$H_2O_2$ process, the pH values did not affect the removal efficiency. The optimal mole ratio of $H_2O_2/Fe^{2+}$ for lindane degradation is about 1.0 in Photo-Fenton process. Also, the experimental results showed that lindane removal efficiency increased with the decrease of initial concentration of lindane. Under the same conditions, the order lindane of removal efficiency is as following : Photo-Fenton process > UV/$H_2O_2$ process > $H_2O_2$ process. In addition, intermediate products were identified by GC-MS techniques. Than PCCH(Pentachlorocyclohexene) was identified as a reaction intermediate of the Photo-Fenton process.