• Journal of Astronomy and Space Sciences
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• 제39권3호
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• pp.87-98
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• 2022

The Far-UltraViolet (FUV) imager onboard the Ionospheric Connection Explorer (ICON) spacecraft provides two-dimensional limb images of oxygen airglow in the nightside low-latitude ionosphere that are used to determine the oxygen ion density. As yet, no FUV limb imager has been used for climatological analyses of Equatorial Plasma Bubbles (EPBs). To examine the potential of ICON/FUV for this purpose, we statistically investigate small-scale (~180 km) fluctuations of oxygen ion density in its limb images. The seasonal-longitudinal variations of the fluctuation level reasonably conform to the EPB statistics in existing literature. To further validate the ICON/FUV data quality, we also inspect climatology of the ambient (unfiltered) nightside oxygen ion density. The ambient density exhibits (1) the well-known zonal wavenumber-4 signatures in the Equatorial Ionization Anomaly (EIA) and (2) off-equatorial enhancement above the Caribbean, both of which agree with previous studies. Merits of ICON/FUV observations over other conventional data sets are discussed in this paper. Furthermore, we suggest possible directions of future work, e.g., synergy between ICON/FUV and the Global-scale Observations of the Limb and Disk (GOLD) mission.

• 한국응용곤충학회지
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• 제14권3호
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• pp.155-161
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• 1975

본 실험은 Corynebacterium속 식물병원세균에 관한 연구의 일환으로서 Corynebacterium속 식물병원세균의 종 및 속으로서의 특성을 구명함과 동시에 C. sepedonicum이 생성하는 Rumiflabin에 기초를 둔 ultraviolet method의 재검토를 위하여 행하여 진 것으로 vitamin B군의 정량은 미생물 정량에 의하였다. 대다수의 식물병원세균은 Thiamine (vitamin $B_1$), Nicotinic acid, Biotin 및 안식향산을 생장물질로서 사용하였다. Riboflavin은 corynebacterium속 식물 병원세균 (C. rathay 및 C. fascians는 제외)은 물론 타속의 식문병원세균도 생성하는 점으로 Corynebacterium속 식물병원 세균의 특성이 아니라는 점이 구명되었으며 sepedonicum에 의하여 발생되는 감자의 윤부병과 청고병과의 감별에 사용되어온 Ultra-violet light법은 재검토되어야 한다.

• 한국표면공학회지
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• 제42권2호
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• pp.59-62
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• 2009

Antireflection pattern, moth-eye structure, was fabricated on lens using Ultra Violet nanoimprint lithography and flexible template. Ni template with conical shaped structure was used as a master template to molding. The flexible poly vinyl alcohol template was fabricated by molding. This poly vinyl alcohol template was used as an imprint template of imprint at lens. Using Ultra Violet nanoimprint lithography and poly vinyl alcohol template, polymer based moth-eye structure was formed on lens and its transmittance was increased up to 94% from 92% at 550 nm wavelength.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2011년도 제40회 동계학술대회 초록집
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• pp.210-210
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• 2011

The effects of CH2F2 and N2 gas flow rates on the etch selectivity of silicon nitride (Si3N4) layers to extreme ultra-violet (EUV) resist and the variation of the line edge roughness (LER) of the EUV resist and Si3N4 pattern were investigated during etching of a Si3N4/EUV resist structure in dual-frequency superimposed CH2F2/N2/Ar capacitive coupled plasmas (DFS-CCP). The flow rates of CH2F2 and N2 gases played a critical role in determining the process window for ultra-high etch selectivity of Si3N4/EUV resist due to disproportionate changes in the degree of polymerization on the Si3N4 and EUV resist surfaces. Increasing the CH2F2 flow rate resulted in a smaller steady state CHxFy thickness on the Si3N4 and, in turn, enhanced the Si3N4 etch rate due to enhanced SiF4 formation, while a CHxFy layer was deposited on the EUV resist surface protecting the resist under certain N2 flow conditions. The LER values of the etched resist tended to increase at higher CH2F2 flow rates compared to the lower CH2F2 flow rates that resulted from the increased degree of polymerization.

• 한국대기환경학회지
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• 제22권6호
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• pp.922-928
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• 2006

An absolute absorption cross section of benzene was measured with a spectrometer system including a mono-chrometer and a grating in the wavelength region of $240{\sim}280nm$ under the atmospheric pressure and room temperature in the laboratory. A certificated reference benzene gas ($98{\mu}mol/mol$ in $N_2$) was used to measure its absorption cross section. A 710 mm cell with a quartz window and a 150 W Xe arc lamp were employed. The magnitude of absorption cross section of $1.41{\times}10^{-18}cm^2$ was lower than that of the reference spectra ($2.5{\times}10^{-18}cm^2$) of high resolution spectrometer, Total measurement uncertainty was estimated to be 4.0%.

• Journal of Preventive Medicine and Public Health
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• 제2권1호
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• pp.1-4
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• 1969

35 samples of Korean fermented foodstuffs were tested to isolate and to identify for aflatoxins. Aflatoxin $G_1$ was detected in samples of soybean and Kanjang (Soybean sauce), and aflatoxins $G_1$ & $G_2$ in Meju (fermented soybean mass) and Dwenjang (fermented soybean paste). In the culture media of Aspergillus flavus aflatoxins $B_1,\;B_2,\;G_1\;and\;G_2$ were also isolated and identified. Aflatoxins were confirmed by the thin layer chromatography with methanol : chroroform (5:95v/v) developer and the ultra violet absorption spectrum.

• 약학회지
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• 제45권6호
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• pp.724-729
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• 2001

Melanogenesis is a physiological process resulted in the synthesis of melanin pigments, which has a role in protecting skin front the damaging effect of ultra-violet (UV) radiation. The main aim of the present study was to examine the effect of Ulmus davidiana var. japonica(UL) on Melanogenesis. Cells were cultured in the presence of various concentrations of Ulmus davidiana var. japonica for 48 h, and there were estimated total melanin contents as a final product and activity of tyrosinase, a key enzyme, in Melanogenesis. Among the four solvent extracts tested, EtOAc extract mostly increased tyrosinase activity, And EtOAc extract increased the melanin contents and tyrosinase activity in a dose-dependent manner. Especially It was observed that 100$\mu\textrm{g}$/ml EtOAc extract promotes melanin secretion in B16/F10 melanoma cells by 140% at 48 h treatment and activity of tyrosinase increased by 180% in the presence of same concentration. In conclusion, as for EtOAc extract treatment, there was no effect on the viability of B16/F10 cell, only to stimulate Melanogenesis.

• 한국의류학회지
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• 제45권6호
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• pp.1052-1062
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• 2021

This study aims to confirm the possibility of Ultra-Violet (UV)-printed 3D printing materials using thermal polyurethane (TPU) with CMYK colors by applying an eco-friendly UV digital printing process. A UV-printed 3D printing TPU material was prepared with cycles of UV printing and CMYK colors. Dyeability of the 3D TPU samples with cycles of UV printing and CMYK were analyzed for thickness, weight, surface roughness, reflectance, colorimetry, and K/S values. The thickness and weight of 3D-printed TPU samples with cycles of UV printing are increased with overprints from 1 to 5. The surface roughness of 3D-printed TPU samples with increasing UV prints were decreased, meaning that the surface of TPU samples becomes gradually smoother. The reflectance spectra of CMYK UV-printed TPU samples showed the surface reflectance within each characteristic wavelength of CMYK. The 3D-printed TPU samples, subjected to UV printing twice or more, showed low surface reflectance. After examining the L^*a^*b^* of the 3D-printed TPU samples by the cycles of UV printing, the study found that the more UV got printed more than 2 times, the closer the color to each CMYK.

• Journal of Photoscience
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• 제7권2호
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• pp.53-58
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• 2000

We performed the cloning of a chalcone synthase (CHS) gene, the key enzyme in the anthocyanin biosynthesis, from the cDNA library constructed with grape suspension cells irradiated UV-B. The PCR fragment was used to cloning the CHS gene. One CHS cDNA clone containing an open reading frame and a partial stilbene synthase (STS)cDNA, the stilbene-type phytoalexin, were isolated. The CHS cDNA clone (VCHS) showed 87% sequence homology with VvCHS (V.vinifea) and 72.3% identity with VSTSY(V.vinifea). its amino acid sequences were longer than any other CHS genes as 454 residues. Two genes were weakly expressed in white light irradiated cells, but highly induced in UV-B irradiated condition during 32 hours. Interestingly, the STS was quickly and abundantly expressed from 2 hours when supplemented with jasmonic acid (JA) and the maximum expression was observed at 4 hours and then gradually decreased. But, the additional UV-B or white light quickly degraded the STS expression than only JA treated grape suspension cells. The CHS also was rapidly induced with JA and the synergistical effect was observed at the addigional light treatment of UV-B or white light. These results are indicated that CHS and STS have different response mechanisms against the environmental stresses.

• 약학회지
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• 제46권1호
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• pp.75-80
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• 2002

Quercetin is one of the bioflavonoid compounds and has multiple biological effects such as antioxidant and effective anti-inflammatory agent. Melanin has an important role in protecting human skin from the damaging effects of ultra-violet W) radiation. We studied the effect of quercetin on proliferation of B16/F10 melanoma cells. After 48h treatment of cells with quercetin, the cells exhibited a dose-dependent inhibition in their proliferation without apoptosis. Therefore, the decrease in cell numbers may be due to cell growth arrest, not due to cell death by cytotoxicity. We also investigated the effect of quercetin on melanogenesis of this cells. B16/F10 melanoma cells were grown for 48h in the presence of 0.01~50$\mu\textrm{g}$/ml quercetin and the total melanin contents were measured. Quercetin stimulated melanization of the cells in low concentrations (0.01~20$\mu\textrm{g}$/ml), whereas it inhibited melanization in high concentrations (30~50$\mu\textrm{g}$/ml). It was observed that quercetin differently regulates melanogenesis of B16/F10 melanoma cells dependent on its concentrations.