• 한국결정성장학회지
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• 제6권4호
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• pp.564-570
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• 1996

급속 열산화 없이 다공성 실리콘으로부터 적색 및 청색 발광을 관찰할 수 있었다. 묽은 HF 농도에서, 특히 짧은 양극 산화 북식으로제조한 aged 된 다공성 실리콘은 청색band 의 증가를 나타내었다. 상온에서 측정된 발광 decay 시간은 약 100 ps를 나타내었고 20K에서 측정된 값에 비하여 상당히 빠른 값을 지니고 있었다. 청색 광발광 peak 최대값은 액체질소온도에서 청색전이를 나타내지 않았다. 그러나 적색 광발광 band는 77K 에서 적색으로 전이를 하였고 황색을 나타내었다. 적색 발광의 origin은 Si 결정과 연관이 있는 것으로 사료되어지는 한편 청색 발광은 Si결정과 무관한 것으로 생각되어 진다.

• The Korean Journal of Ceramics
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• 제4권1호
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• pp.28-32
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• 1998

This paper reports on photoluminescence (PL), luminescence decay curves, and compositional analysis of porous silicon(PS) which is aged under air ambient by Fourier transform infrared vibrational spectroscopy (FTIR) and by Auger electron spectroscopy (AES). Porous silicos which has been aged under air ambient yields two PL band structures, i.e. blue/violet PL and red PL. The evolution of a blue/violet band is pronounced, especially for thin PS film which is prepared in dilute HF solution. The blue/violet PL band has been observed initially to increrase rapidly with aging, then saturated with further atmospheric aging. The ambient air aged PS exhibits a fast decay time of sub-nanosecond at room temperature and shows appreciably faster decay time than that at 20K. Atmospheric aging of this thin blue/violet luminescing PS yield non-stoichiometric oxide judging from the vibrational spectra of Si-O and AES analysis.

• Journal of the Optical Society of Korea
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• 제11권2호
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• pp.67-70
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• 2007

A Wide Color Gamut Backlight system was studied using a three-band white Light-Emitting Diode. A three-band white light-emitting diode (LED) was fabricated using an InGaN-based blue LED chip that emits 445-nm blue peak, and a green phosphor and red phosphor that emit 535-nm green and 621-nm red peak emissions, respectively, when excited by 450-nm blue light. Using for this three-band white LED, wide color gamut backlight unit (BLU) was attained. The luminance of BLU and CIE 1931 chromaticity coordinates was $1,700Cd/m^2$ and (0.337, 0.346). Color filter matching simulations for this configuration show that the three-band white LED backlight can be enhanced by up to 16% over conventional white LED backlight color gamut.

• Asian Journal of Atmospheric Environment
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• 제5권2호
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• pp.79-85
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• 2011

The purpose of this study is to evaluate the strength of the near-UV wavelength of 380 nm relative to visible and near-IR bands, and to find the suitable wavelength for detecting aerosols by using the Global Imager (GLI) sensor aboard the Advanced Earth Observing Satellite-II (ADEOS-II). Sensitivity analysis is performed for the retrieval of biomass burning aerosols by employing the radiative transfer model Rstar5b. It is determined that background surface reflectance in the blue band is similar to that in the near-UV band, and that wavelengths in the blue bands are more sensitive to the Aerosol Optical Thickness (AOT) than wavelengths in the near-UV band. The Total Ozone Mapping Spectrometer (TOMS) Aerosol Index (AI) is used in the indirect method used for aerosol retrieval, and the wavelength pair 380 nm and 460 nm is determined to be the most sensitive to the AOT. The results of this study suggest that wavelengths in the blue bands are suitable for detecting biomass burning aerosols over the Korean peninsula.

• Bulletin of the Korean Chemical Society
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• 제30권7호
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• pp.1611-1615
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• 2009

We designed new anthracene-based host material to increase color purity as well as device efficiency. The new blue host, 9,10-bis(2,4-dimethylphenyl)anthracene (BDA), has highly twisted structure and wide band gap due to ortho interaction between anthracene and introduced 2,4-dimethylphenyl substituents. BDA exhibited deep blue fluorescence in solution (${\lambda}_{max}$ = 410 nm) and in solid state (${\lambda}_{max}$ = 429 nm), respectively, with the wide optical band gap (E = 3.12 eV). Blue-light-emitting OLEDs using obtained host and 2% Flu-DPAN as emitter showed 8 cd/A of high efficiency as well as high color purity [CIE coordinates = (0.15, 015)].

• 자원환경지질
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• 제26권1호
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• pp.107-114
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• 1993

For the blue sapphires from Santung, China, the color change before and after has been investigated by UV-Visible spectrophotometry method. The blue sapphires from Shantung show four groups of absorption bands: the bands A (374, 386 and 450 nm) being attributed to single $Fe^{3+}$ ion, the band B (560, 579 and $704n{\breve{m}}$) to $Fe^{2+}$/$Ti^{4+}$ pairs, the band C (-800 nm) to $Fe^{2+}$/$Fe^{3+}$ pairs, and the D (528 nm) to $Ti^{3+}$ dd transitions. From those UV-VIS characteristics the origin of blue color of the sapphires is confirmed to be attributed by the factors such as $Fe^{2+}$/$Fe^{3+}$ and $Ti^{3+}$/$Ti^{4+}$. The absorption spectra of natural blue sapphires before and after heat treatment show distintive features, comparing with those of sapphires from other localities: the bands of 689 nm and of $Cr^{3+}$ are not recorded on the spectra of sapphires from Shantung. The band (492 nm), which resulted from $Ti^{3+}$, is not shown and the intensity of the band 528 nm decreases after the heat treatment. Decoloration of ink-blue sapphires are found to be successful by heat treatment with the control of annealing and atmosphere. During the diffusion process the excess components of impurities contained originally in the host crystal were expelled to the surface of crystals, enhancing the transparency of the crystals noticeably.

• 한국측량학회:학술대회논문집
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• 한국측량학회 2007년도 춘계학술발표회 논문집
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• pp.187-190
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• 2007

This study is for analyzing best band in image matching using correlation coefficient of left and right images of stereo image pair, lot red, green, blue band images separated from color aerial photo and gray image converted from the same color aerial photo image. The image matching is applied to construct Digital Elevation Model(DEM) or terrain data. The correlation coefficients and variation by change of pixel patch size are computed from pixel patches of which sizes are $11{\times}11{\sim}101{\times}101$. Consequently, the correlation coefficient in red band image is highest. The lowest is in blue band. Therefore, to construct terrain data using image matching, the red band image is preferable. As the size of pixel patch is growing, the correlation coefficient is increasing. But increasing rate declines from $51{\times}51$ image patch size and above. It is proved that the smaller pixel patch size than $51{\times}51$ is applied to construct terrain data using image matching.

• 한국동물학회지
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• 제12권3호
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• pp.94-102
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• 1969

盛熱한 albino 雄性 흰쥐를 對照群과 實驗群으로 나누어 對照群에는 0.9% 生理食鹽水를, 實驗群에는 methylene blue(38mg/kg, 食鹽水에 溶解 pH 7.4)를 各各 腹腔注射處理하였다. 約 30 分後 兩群 共히 總線量 360 rads 인 $^60 Co$의 r 線을 一時 全身照射하였다. 照射後 212時間에 걸쳐 血淸總乳酸脫水素酵素의 含量(Cabaud and Droblewski 1958)과 血淸을 비롯하여 肝, 心臟, 精巢組織의 乳酸脫水素酵素의 同位酵素vnfortys(Preston et al., 1965)을 各各 測定하여 methylene blue 의 放射線에 對한 防禦　果를 硏究調査하였다. 一般的으로 血淸總乳酸脫水素酵素의 含量은 兩群共히 r 線照射後 初期에 增加하나 特히 methylene blue 實驗群인 處理群은 對照群인 生理食鹽水群에 比하여 15 및 64 時間區에서 增加의 遲滯性을 나타내었다. 血淸과 肝, 心臟 및 精巢組織의 乳酸脫水素酵素의 同位酵素는 兩群共히 線照射後 40과 116 時間區에서 陽極쪽의 同位酵素 푸랙숀 含量은 減少한다. 照射群 methylene blue 處理群의 血淸과 肝 및 精巢組織 乳酸脫水素酵素의 同位酵素패턴에서는 對照群과 別差異가 없었으나 特히 methylene blue 處理群의 心臟組織은 對照群에 比하여 若干의 增減의 遲滯性을 나타내었다. 兩群共히 照射後 血淸乳酸脫水素酵素含量의 增加는 同位酵素푸랙숀 1의 增加에 基因된다고 思料되며 이상의 結果로 미루어 보아 總乳酸脫水素酵素 活性과 心臟組織의 乳酸脫水素酵素의 同位酵素패턴에 있어서 methylene blue가 放射線防禦　果가 있는 것으로 思料된다.

• 센서학회지
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• 제28권4호
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• pp.262-265
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• 2019

The effect of inter-band transition on surface plasmon resonance in gold thin film was investigated. We induced localized inter-band transition in the film by using incident light on its surface from a green laser (532 nm) source, and the surface plasmon resonance for inter-band transition was investigated at different wavelengths. It was determined that the reflectivity of blue light (450 nm) was significantly reduced in the region where the green laser was incident. We demonstrated that this decrease is mainly due to the coupling between the blue light and the surface plasmon resonance of excited electrons in higher energy states, based on experimental results for the incident and polarization angle-dependent reflectivity of the blue light.

• 한국안광학회지
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• 제5권2호
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• pp.201-205
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• 2000

혼합색에 의한 착색 렌즈의 칼라는 감산혼합 법칙을 따르며 착색 렌즈 평가는 광흡수의 특성과 칼라분석에 의한다. Yellow(x)-Blue(1-x) 칼라 렌즈의 광흡수 특성은 500 nm 이하 단 파장에서 황색에 의해(x) 의존하고 550~650 nm 영역 흡수는 청색에 의존하며, 이 흡수 band는 전이금속의 ion화에 의한 peak이다. CIE system인 $L^*a^*b^*$에 의해 분석한 Yellow(x)-Blue(1-x) 칼라 렌즈의 color 특성은 x가 작아질수록 $+a^*$쪽으로 이동하였고 모두 +0.6이내 존재해 채도가 낮은 순수 칼라를 형성하였다.