• Bulletin of the Korean Chemical Society
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• v.33 no.2
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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.

• Journal of the Korean Chemical Society
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• v.6 no.2
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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. ${\nu}={\nu}_{\circ}-({\Delta}{\nu}_x+{\Delta}{\nu}_y)$

• Journal of the Korean Society of Clothing and Textiles
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• v.25 no.5
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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.

• The Bulletin of The Korean Astronomical Society
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• v.37 no.2
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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.

• YAKHAK HOEJI
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• v.30 no.2
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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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• v.12 no.2
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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.

• Korean Journal of Veterinary Service
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• v.41 no.2
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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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• v.12 no.3
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• pp.35-40
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• 1984

The ultraviolet absorption spectra of AcBr lignin (Acetyl Bromide lignin) from 10 species grown in Mt. Jiri were determined. There were 3 peak positions, at 249nm (max peak), at 267-268 nm (shallow min. peak) and at 280 nm (lower max. peak). The Bjorkman lignin and lignin sulfonic acid spectra had shoulders, but the AcBr lignin had not them. Average absorbances and absorptivities of the AcBr lignins at peak positions were $0.367{\pm}0.0015$, $24.56{\pm}0.0535$, at 249 nm, $0.278{\pm}0.0016$, $18.50{\pm}0.0569$, at 267-268 nm and $0.306{\pm}0.0016$, $20.42{\pm}0.0627$ at 280 nm, respectively.

• Journal of Astronomy and Space Sciences
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• v.21 no.4
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• pp.243-248
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• 2004

We present measurements of interstellar CO absorption lines in the spectra of 7 early-type stars that were observed with the FUSE(Far Ultraviolet Spectroscopic Explore.) Among 54 early-type target stars in the Galactic disk and halo observed with the BBFS(Berkeley Extreme and Far-ultraviolet Spectrometer), we choose 7 program stars (HD 37903, HD 97991, HD 149881, HD 156110, HD 164794, HD 214080 and HD 219188) which have only a single velocity component in the high-resolution optical measurements, in order to avoid line blending. To analyze the CO molecule, we select the E-X (0-0) band at $1076{\AA}$, which has a large oscillate. strength and is not blended with other interstellar absorption lines. We detect the CO absorption lines in three (HD 37903, HD 164794, and HD 214080) out of seven targets, and derive CO column densities for those targets. We also estimated the CO to $H_2$ ratios toward the three stars, based on the previously estimated $H_2$ column densities.

• Korean Journal of Food Science and Technology
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• v.13 no.2
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• pp.114-120
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• 1981

A rapid and simple method for detecting colors was attempted on the basis of absorption and emission spectra of reflected light at $45^{\circ}$ angle from color-adsorbed filter paper illuminated by ultraviolet light through interference filter. Absorption spectra of prepared samples revealed more characteristic patterns than emission spectra. Detection of colors was readily accomplished by the investigation of wave length range, distribution pattern, the number of absorption bands and the degree of quenching.