• Bulletin of the Korean Chemical Society
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• 제33권2호
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• pp.597-600
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• 2012

Polyynes were formed by laser ablation of a graphite target in deionized water ($H_2O$ and $D_2O$) and various organic solvents such as acetonitrile, n-hexane, and c-hexane and were identified by analyzing ultraviolet (UV) absorption and Raman spectra. We assigned the major UV absorption peaks that coincided with the electronic transitions corresponding to linear polyyne chains. The UV absorption peak intensities of a polyyne solution decreased as the holding temperature of the solution increased. Also, the absorption spectra of polyynes obtained by laser ablation of a graphite target at different volume fractions of $H_2O$ and $D_2O$ were examined.

• 대한화학회지
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• 제6권2호
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• pp.170-175
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• 1962

The ultraviolet and visable absorption spectra of trans, cis-azoxybenzene, substituted azoxybenzenes and their conjugate acids have been studied. The 320-350$m{\mu}$ main bands of free-base of azoxybenzenes are due to ${\pi}{\to}{\pi}^{\ast}$ transition. These bands of their conjugate acids shown bathochromic shift into visible range. The following emperical relationship between absorption maxima of the main bands was found. ${\lambda}_{max}={\lambda}^{\circ}_{max}+{\Delta}{\lambda}_x+{\Delta}{\lambda}_y$ This relationship in terms of wave number is also hold in good agreement. ${\nu}={\nu}_{\circ}-({\Delta}{\nu}_x+{\Delta}{\nu}_y)$

• 한국의류학회지
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• 제25권5호
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• pp.925-932
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• 2001

The influence of ultraviolet(UV)-ray in sun light on human skin has been noted. Textiles can provide protection against harmful UV-radiation. Normally UV-absorbing finishes are used to get better protection. The purpose of this study is to evaluate the UV-cut properties of cotton fabrics treated with UV-absorber. 2,2-dihydroxy-4,4-dimethoxbenzophenone, as UV-absorber was applied to 100% cotton fabric. Reagents added in finishing solution were Triton X-100, polyethylene glycol 400, and $MgCl_2{\cdot}6H_2O$, and C.I. Direct Red 81. Both untreated and treated cotton fabrics were exposed to a xenon arc lamp for 20 and 80 hours. UV absorption spectra of finishing solutions and UV transmission spectra of fabrics were measured by the UV/VIS spectrophotometer. The results of this study can be summarized as follows. The results of this study can be summarized as follows. Absorption and the related transmission spectra were modified in a controlled way with UV-absorber. Absorption effect of UV-absorber was improved by adding Triton X-100, PEG 400, and $MgCl_2{\cdot}6H_2O$ in finishing solution. The UV absorption of finishing solution was in the following order: U/D/T/P/M>D/T/P/M> D/T> D/P, D>U/T/P/M>U/T>T/P/M>T. The UV transmittance of cotton fabrics was remarkably decreased by the application of UV-absorber and additives. The UV-cut properties were most improved by the application of U/D/T/P/M.

• 천문학회보
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• 제37권2호
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• pp.134.2-134.2
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• 2012

Discrete auroras, with unique shapes embedded in diffuse auroras, are generally associated with precipitating electrons that originate from the plasma sheet and are accelerated on the way as they travel to polar regions along the field lines. Two acceleration mechanisms have been proposed: quasi-static electric fields and dispersive Alfven waves, which are believed to yield monoenergetic peaks and broadband features in the particle spectra, respectively. Hence, it should be interesting to see how the two different mechanisms, through their characteristic spectra of the accelerated electrons, produce distinct auroral images and spectra, especially in the far ultraviolet (FUV) wavelengths as the long and short Lyman-Birge-Hopfield (LBH) bands exist as well as the strong absorption band of molecular oxygen in the FUV band. In fact, we have previously shown, using the simultaneous observations of precipitating electrons and the corresponding FUV spectra, that the discrete auroras associated with inverted-V events have a stronger relative intensity of the long LBH to the short LBH compared to diffuse auroras, especially when the peak energy is above a few keV. In this paper, we would like to focus on the differences in the FUV images and spectra between the two discrete auroras of the monoenergetic and broadband cases, again based on the study using the dataset of simultaneous observations of particles and FUV spectral images.

• 약학회지
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• 제30권2호
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• pp.100-103
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• 1986

The second derivative absorption spectra of acetaminophen in commercial tablet forms were measured without prior separation from other pharmaceutical adjuvants. The second derivative spectra of acetaminophen were found to have no influence on the characteristic absorbance band of it. A plot of 25 sets of the ordinate (Z) values with various acetaminophen concentrations mixed in other additives gave a straight line (correlation coefficient, 0.9999) and the slope was 2.901${\times}10^{-2}Z$ value/($\mu\textrm{g}$/ml). The procedures were sufficiently sensitive, precise and economical for the assay of tablets of acetaminophen.

• Bulletin of the Korean Chemical Society
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• 제12권2호
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• pp.207-210
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• 1991

Ultraviolet spectra of 5-and 6-uracilyl compounds which contain conjugated double bonds were obtained and their characteristic phenomena were examined. 5-Formyluracil and 6-methyl-5-formyluracil showed bathochromic shifts which should be expected from a conjugated carbonyl compound. 6-Formyluracil did not show any shift in absorbing wavelength. 5-and 6-uracilylacrylic acid derivatives, on the other hand, showed absorption at similar wavelengths, indicating the presence of a hexatriene chromophore. The ratio of ${\Delta}ν/J$ in nuclear magnetic resonance spectra of those compounds decreased drastically as the acrylic acids or esters were converted into amides.

• 한국동물위생학회지
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• 제41권2호
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• pp.125-131
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• 2018

This study investigated the effects of the alkaline detergent and acid rinse used for cleaning milking machines on the rubber composition of the newly-developed teat cup liners. The samples prepared for use in the clean-in-place process were analyzed by ultraviolet spectrophotometer, ion chromatography and liquid chromatography. In the absorption spectrum of the first sample solution, the form of absorbance or absorption peak was largely different, compared to the absorption spectrum of alkaline detergent alone, but in the absorption spectra of the second and third sample solutions, the absorbance decreased, which was similar to the absorption spectrum in the pure acid detergent. In the ion chromatogram, two main peaks only, which might be shown by the pure alkaline detergent alone, were measured. In the liquid chromatograms, however, new peaks were observed in addition to the two main peaks caused by the pure alkaline detergent alone, which suggested that various molecular materials were created or eluted from the liner by the reaction with the alkaline detergent, but when washed with the acid detergent, any ion species were not produced. Therefore, we propose that an acid rinse should be applied, after cleaning the milking machine with the alkaline detergent.

• Journal of the Korean Wood Science and Technology
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• 제12권3호
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• pp.35-40
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• 1984

지리산산(智異山産) 침엽수재(針葉樹材) 10개(個) 수종(樹種)에 대(對)한 AcBr lignin의 UV spectrum을 조사(調査)하여 본 바 각(各) 수종(樹種) 모두 spectrum curve의 정점(頂點)은 249nm(Max. peak), 267-268nm(Shallow min. peak), 280nm(Lower max. peak)에 있었으며 Bjorkman lignin이나 lignin sulfonic acid 등(等)의 UV spectrum 상(上)에서 볼 수 있는 견(肩)은 AcBr lignin의 spectrum curve 상(上)에서는 볼 수 없었으며 각(各) 정점(頂點)의 10개(個) 수종(樹種) 평균(平均) 흡광도(吸光度)와 흡광계수(吸光係數)는 249nm에 각각(各各) $0.367{\pm}0.0015$, $24.56{\pm}0.0535$, 267-268nm에서 $0.278{\pm}0.0016$, $18.50{\pm}0.0569$ 였고 280nm에서는 $0.306{\pm}0.0016$, $20.42{\pm}0.0627$ 이었다.

• Journal of Astronomy and Space Sciences
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• 제21권4호
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• pp.243-248
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• 2004

FUSE(Far Ultraviolet Spectroscopic Explorer)를 이용해 7개의 초기형 별 방향에 존재하는 CO 흡수선을 관측했다. BEFS(Berkeley Extreme and Far-ultraviolet Spectrometer)로 관측한 54개의 초기형 별들 중에서 이번 논문에서는 시선방향으로 1개의 성간운만 존재하는 7개의 별(HD 37903, HD 97991, HD 149881, HD 156110, HD 164794, HD 214080, HD 219188)들을 선택해서 분석했다. CO 분자의 분석을 위해 자외선 영역에서 수소분자의 흡수선에 의해 가려지지 않는 E-X(0-0)($1076{\AA}$) 흡수선이 있는지 확인했으며 그 결과 3개의 별 방향에 존재하는 성간운에 대해서 CO 흡수선이 있는 것을 발견했다. 그 흡수선의 분석을 통해 성간운에 존재하는 CO의 기둥밀도를 구했고, 이번 논문에서의 결과와 이전에 구했던 수소분자의 기둥밀도로부터 CO분자와 수소분자 사이의 비율(CO to $H_2$ ratio)을 계산할 수 있었다.

• 한국식품과학회지
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• 제13권2호
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• pp.114-120
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• 1981

색소(色素)를 흡착(吸着)시킨 여지(濾紙)를 시료(試料)로 간섭(干涉)필터를 통한 자다선(紫多線)을 조사(照射)한 경우에 $45^{\circ}$ 반사각(反射角)에서 발광(發光) 및 소광(消光)의 세기를 측정하여 신속하고 간편하게 색소(色素)를 감별(鑑別)할 수 있는 방법(方法)을 시도(試圖)하였다. 발광(發光) 스펙트럼 보다는 흡수(吸收) 스펙트럼이 보다 특징적인 패턴을 나타냈다. 흡수대(吸收帶)의 파장영역(波長領域), 분포상태(分布狀態) 및 개수(個數)와 소광(消光)정도를 조사하므로써 착색료(着色料) 종류가 용이하게 판별되었다.