• Journal of the Korea Society of Computer and Information
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• v.10 no.1 s.33
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• pp.1-6
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• 2005

White light emission is very important for applying electroluminescent device to full display, backlight and illumination light source. In this letter, Multilayer molecular organic white-light-emitting device using thin nim of blue material nitro-DPVT with fluorescent dye Rubrene for an orange emission were fabricated. The basic structure of the fabricated device is a-NPD / nitro-DPVT / nitro- DPVT:Rubrene / BCP/ Alq3. Aluminum is used as the cathode material and ITO was anode material. The white light emission spectrum covers a wide range of the visible region and the Commission Internationale do I'E clairage (C.I.E.) coordinates of the emitted light was ((0.3347, 0.3515) at 14V. The turn voltage is as low as 2.5V and quantum efficiencies are $0.35\%$.

• Bulletin of the Korean Chemical Society
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• v.35 no.1
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• pp.189-196
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• 2014

Water dispersible ZnS based nanocrystals: ZnS (blue), ZnS:Cu (green) and ZnS:Mn (yellow-orange) were synthesized by capping the surface of the nanocrystals with a mercaptopropionic acid (MPA) molecule. The MPA capped ZnS based nanocrystal powders were characterized by using XRD, HR-TEM, EDXS, FT-IR, and FT-Raman spectroscopy. The optical properties of the colloidal nanocrystals were also measured by UV/Vis and photoluminescence (PL) spectroscopies in aqueous solvents. The PL spectra showed broad emission peaks at 440 nm (ZnS), 510 nm (ZnS:Cu) and 600 nm (ZnS:Mn), with relative PL efficiencies in the range of 4.38% to 7.20% compared to a reference organic dye. The measured average particle sizes from the HR-TEM images were in the range of 4.5 to 5.0 nm. White light emission was obtained by mixing these three nanocrystals at a molar ratio of 20 (ZnS):1 (ZnS:Cu):2 (ZnS:Mn) in water. The measured color coordinate of the white light was (0.31, 0.34) in the CIE chromaticity diagram, and the color temperature was 5527 K.

• Journal of the Korean Graphic Arts Communication Society
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• v.24 no.2
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• pp.49-59
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• 2006

In this paper, a transparent film exposed the effect of heat cut-off, reveal as means of the prevention to wrong operation of parts of display and forgery of the credit card, also it will intercept rising of the temperature in interior of a room and car by diminish the influx of near-infrared ray wavelength of solar energy come from the window. As in the past a film which absorb a wavelength of $800{\sim}2500nm$ in near-infrared ray, manufactured in physical vapor deposition(PVD), chemical vapor deposition(CVD) to using ATO, ITO of inorganic materials or sputtering method. but it has lots of problem in manufacture. On the other hand, recently a paper said it easily form a transparent film to using organic dye. This paper show synthesis of many derivatives used in Ni-complex and then it investigate to optical property and durability of flim by make the transparent film.

• Environmental Analysis Health and Toxicology
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• v.24 no.1
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• pp.33-41
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• 2009

Among the toxicants in the environment dioxin-like compounds, including TCDD(2,3,7,8-Tetrachlorodibenzo-p-Dioxin), are well known as carcinogen and teratogen. TCDD the most toxic of these compounds, may result in a wide variety of adverse health effects in humans and environment, including carconogenesis, hepatotoxicity, teratogenesis, and immunotoxicity. Also TCDD increases superoxide, peroxide radicals and induces oxidative stress that leads to breakage of DNA single-strand and mitochondrial dysfunction. Recently, there have been reports that persistent organic pollutants(POPs) may be causing metabolic disease through mitochondrial toxicity. In order to examine if dioxin brings about toxicity on mitochondria directly, we measured the change of the mitochondrial membrane potential after exposure to TCDD using JC-1 dye. After short time exposure of dioxin, mitochondrial depolarization was observed but it recovered to the control level immediately. This TCDD effect on mitochondrial membrane potential was not correlated either to the production of reactive oxygen species(ROS) or extracellular $Ca^{2+}$ by TCDD. Less than 2 hours exposure of TCDD did not show any change in ROS production but 0.25 nM TCDD for 48 hours or 0.5 nM TCDD for 12 hours exposure did increase in ROS production. Under these conditions of ROS production by TCDD, no changes in the mitochondrial membrane potential by TCDD was observed.

• YAKHAK HOEJI
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• v.42 no.2
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• pp.144-148
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• 1998

One hundred and seventeen crude drugs were screened for DNA-binding activity in vitro. The DNA-methyl green assay is a useful biochemical screen for the detection or development of biologically active compounds which bind to DNA. This assay is based upon the fact that free methyl green undergoes rapid spontaneous molecular rearrangement to its colorless carbinol base so that the liberation of the dye from DNA by displacement can be followed spectrophotometrically as a decrease in absorbance at 65Onm. Seven methanolic extracts of crude drugs including Cinnamomi Cortex spissus, Coicis Semen, Coptidis Rhizoma, Perillae Semen, Plantaginis Semen, Polygalae Radix and Zanthoxyli Fructus showed less than 2,000${\mu}$g/ml as their $IC_{50}$ values. The active principles of Plantaginis Semen and Zanthoxyli Fructus were transferred into organic solvents, which showed the $IC_{50}$ values with 588 and 574${\mu}$g/ml, respectively. These fractions have been selected for isolation of biologically active constituents.

• Bulletin of the Korean Chemical Society
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• v.32 no.3
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• pp.815-820
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• 2011

Three kinds of organometallic compounds (chromium acetylacetonate, magnesium acetate and vanadyl acetylacetonate) were used as transition metal precursor, titanium n-butoxide and multi-walled carbon nanotube as titanium and carbon precursor to prepare metal oxide-CNT/$TiO^2$ composites. The surface properties and morphology of metal oxide-CNT/$TiO^2$ composites were by Brauer-Emett-Teller (BET) surface area measurement, scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and energy dispersive X-ray (EDX) analysis. The photocatalytic activity of prepared metal oxide-CNT/$TiO^2$ composites was determined by the degradation effect of methylene blue in an aqueous solution under irradiation of visible light.

• Carbon letters
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• v.18
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• pp.30-36
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• 2016

Well-dispersed Ag₃VO₄ nanoparticles @polyacrylonitrile (PAN) nanofibers were synthesized by an easily controlled, template-free method as a photo-catalyst for the degradation of methylene blue. Their structural, optical, and photocatalytic properties have been studied by X-ray diffraction, transmission electron microscopy, field-emission scanning electron microscopy equipped with rapid energy dispersive analysis of X-ray, photoluminescence, and ultraviolet-visible spectroscopy. The characterization procedures revealed that the obtained material is PAN nanofibers decorated by Ag₃VO₄ nanoparticles. Photocatalytic degradation of methylene blue investigated in an aqueous solution under irradiation showed 99% degradation of the dye within 75 min. Finally, the antibacterial performance of Ag₃VO₄ nanoparticles @PAN composite nanofibers was experimentally verified by the destruction of Escherichia coli. These results suggest that the developed inexpensive and functional nanomaterials can serve as a non-precious catalyst for environmental applications.

• Journal of the Korean Ceramic Society
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• v.45 no.1
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• pp.36-42
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• 2008

Carbon/$TiO_2$ composite photocatalysts were thermally synthesized with different mixing ratios of anatase to phenol resin through an ethanol solvent dissolving method. The XRD patterns revealed that only anatase phase can be identified for Carbon/$TiO_2$ composites. The diffraction peaks of carbon were not observed, however, due to the low carbon content on the $TiO_2$ surfaces and the low crystallinity of amorphous carbon. The results of chemical elemental analyses of the Carbon/$TiO_2$ composites showed that most of the spectra for these samples gave stronger peaks for carbon and Ti metal than that of any other elements. The BET surface area increases to the maximum value of $488\;m^2/g$ with the area depending on the amount of phenol resin. From the SEM images, small $TiO_2$ particles were homogeneously distributed to a composite cluster with the porosity of phenol resin-based carbon. From the photocatalytic results, the MB degradation should be attributed to the three kinds of synergetic effects, such as photocatalysis, adsorptivity, and electron transfer by light absorption between supporter $TiO_2$ and carbon.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.29 no.1
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• pp.40-43
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• 2016

Transparent color coating films were fabricated on a glass substrate by using sol-gel hybrid binder and organic dye. Sol-gel hybrid binder coating film fabricated with PTMS of 0.03 mole showed a very high pencil hardness of 9 H. As the withdrawal speed increased from 1.0 mm/s to 5.0 mm/sec, The yellowness ($b^*$) of coating glass also gradually increased. The transmittance of yellow color coating glass was 82.6% and the haze of coating glass was 0.35%. Red and blue color coating glasses also showed the high transmittance of 62.4% and 80.6% respectively. The surface hardness of color coating films was 6 H.

• Journal of Energy Engineering
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• v.25 no.2
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• pp.65-78
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• 2016

Initial studies of the photocatalyst has been developed from the field relating to the conversion and storage of solar energy. Recently, the study of the various organic decomposition compound and the water purification and waste water treatment by ultraviolet irradiation in the presence of light or a photocatalyst are being actively investigated. In addition, the oxidized material-carbon nanotubes, graphene-nanocomposites have been studied. Such a complex is suitable as a material constituting the solar cells and photolysis nanoelectronics, including the flexible element due to thermal and chemical stability.