• Textile Coloration and Finishing
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• v.25 no.1
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• pp.18-24
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• 2013

A water soluble spironaphthoxazine (SPO) was synthesized, and its spectral properties were determined. Under UV irradiation, colorless SPO shows intensive blue color while the intensity of its initial fluorescence decreased. In addition, SPO also exhibited high sensitivity to pH stimuli both in colorimetry and fluorometry distinguishing from the spectral appearance observed under UV irradiation. Further, integrating these two optical characteristics a three-state switching system can be established, and all interconversions can be observed by naked-eye.

• Journal of the Korea Furniture Society
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• v.20 no.6
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• pp.560-565
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• 2009

It is known that heat treatment decreases the hygroscopicity of wood. Thus heat-treated wood is good for outdoor construction due to its improved dimensional stability. This study is to investigate the hygroscopicity and discoloration of spruce and birch boards heat-treated above $190^{\circ}C$. The equilibrium moisture contents (EMCs) at all relative humidities decreased with the increase of heat treatment temperature and/or time for both spruce and birch. It was revealed that heat-treatment temperature affected more on the hygroscopicity thaan heat-treatment time. The average basic densities decreased for the spruce specimens, but increased for the birch specimens with an increase of the treatment time and/or temperature. The same heat treatment condition (190-8) made the birch specimens darker than the spruce specimens.

• Journal of Microbiology and Biotechnology
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• v.25 no.12
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• pp.2007-2010
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• 2015

A new chemical inhibitor against severe acute respiratory syndrome (SARS) coronavirus helicase, 7-ethyl-8-mercapto-3-methyl-3,7-dihydro-1H-purine-2,6-dione, was identified. We investigated the inhibitory effect of the compound by conducting colorimetry-based ATP hydrolysis assay and fluorescence resonance energy transfer-based double-stranded DNA unwinding assay. The compound suppressed both ATP hydrolysis and double-stranded DNA unwinding activities of helicase with IC₅₀ values of 8.66 ± 0.26 μM and 41.6 ± 2.3 μM, respectively. Moreover, we observed that the compound did not show cytotoxicity up to 80 μM concentration. Our results suggest that the compound might serve as a SARS coronavirus inhibitor.

• Proceedings of the KOSOMBE Conference
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• v.1995 no.11
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• pp.134-137
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• 1995

Studies on the formulations of the additives such as antioxidants, crosslinking agent, and trans-stilbeneoxide (StO) with polypropylene (PP) have been carried out to improve the resistance of gamma radiation sterilization. The irradiated PP and ethylene-propylene copolymers samples with control and additives were characterized by mechanical tester, colorimetry, and Fourier transform infrared spectroscopy with total attenuated reflectance mode (FTIR-ATR). Crosslinking agent and StO formulated PP showed remarkable radiation resistance and minimum discoloration. Also, radiation resistance of ethylene propylene copolymers with 3% of ethylene contents was better than that of PP homopolymers in the case of no additives. The proposed mechanisms of radiation stabilization with additives are also discussed.

• Journal of the Optical Society of Korea
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• v.14 no.4
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• pp.415-419
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• 2010

A phosphor-conversion white light source is demonstrated using an InGaN-based blue laser diode (LD) and a yellow-emitting phosphor excited by the blue LD. The photometric and colorimetric properties of this blue-LD-based white light source are characterized. When injection current of the LD is 100 mA, luminous flux and luminous efficiency of the white light are found to be over 5 lm and 10 lm/W, respectively. When injection current is >90 mA, luminance is estimated to be larger than 10 Mcd/$cm^2$. In addition, color characteristics of the white light such as chromaticity coordinates, a correlated color temperature, and a color rendering index are found to be quite stable as current and temperature of the LD varies. The demonstrated LD-based white light source is expected to be used in high-brightness illumination applications with good color stability.

• Korean journal of food and cookery science
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• v.18 no.1
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• pp.81-86
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• 2002

Yackwa was prepared by the addition of different amounts of egg white, and the samples were analyzed by texture profile analysis, Hunter's colorimetry and sensory evaluation during 5 days of storage. Tn texture profile analysis, the hardness, gumminess and chewiness of Yackwa were increased in all the samples during storage and the texture parameters were increased by increasing egg white level. No significant difference was observed in the lightness, redness and yellowness (p〉0.05), but Hunter's color values were slightly increased during storage in all the samples. In sensory evaluation, no significant difference was observed among the samples during storage except the increase of crispiness and overall acceptance by the addition of egg white. The results showed that Yackwa prepared with 10 g of egg white/(100 g of other ingredients ---약과재료 얼마당 10g 첨가인지 명확히 해야 함) had an acceptable sensory quality.

• Bulletin of the Korean Chemical Society
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• v.34 no.11
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• pp.3377-3380
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• 2013

The spectrophotometric and electrochemical properties of tetraazo(p-carboxy)phenylcalix[4]arene (p-CAC) in the presence of various metal ions were investigated by UV/Vis spectroscopy and voltammetry in $CH_3CN$. p-CAC showed selective color changes to $Cu^{2+}$ over other metal ions from light orange to colorless, in accordance with hypsochromic shift in UV/Vis spectra. Voltammetric measurements also showed high selectivity for $Cu^{2+}$.

• Journal of the Optical Society of Korea
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• v.19 no.6
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• pp.649-657
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• 2015

We present a surface color measurement including quantities of surface color, methods, and uncertainty evaluation. Based on a relation between spectral reflectance and surface color, we study how an uncertainty of spectral reflectance propagates to surface color. In analyzing the uncertainty propagation, we divide the uncertainty into uncorrelated components, fully correlated components, and correlated components with spectrally varying correlations. As an experimental example, we perform spectro-reflectometric measurements for ceramic color plates. With measured spectral reflectance and its uncertainty evaluation, we determine surface color and analyze uncertainties of the ceramic color plates.

• Archives of Pharmacal Research
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• v.17 no.6
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• pp.415-419
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• 1994

A simple nad rapid colorimetric method for the assay of amodiaquine hydrochloride, chloroquine phosphate and primaquine phosphate is described. The method is based on the interaction of the drug base with bromophenol blue to give a ion-pair complex. The spectra of the complex shows a maxima at 415-420 nm with high apparent molar absorptivities. Beer's law was obeyed in the concentration range 1-8, 2-10 and $2-12{\;}{\mu}{\cdot}ml^{-1}$ for amodiaquine hydrochloride, primaquine phosphate and chloroquine phosphate respectively. The proposed method was applied to the determination of these drugs in certain formulations and the results were favourably comparable to the official methods.

• Proceedings of the IEEK Conference
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• 2002.06d
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• pp.255-258
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• 2002

Recently, Digital TV viewer have been replacing cathode ray tubes (CRT) with Plasma display panel(PDP). But the chromaticity of the primaries are dependent on RGB input signals. And the colorimetry of PDP changes with gray scale and has a poor performance in color reproduction. In this paper we propose the enhanced algorithm of color reproduction considering nonlinear gamut mapping algorithm. In order to test performance of this algorithm we use the sample colors. As a result of experiments, it was confirmed that the color difference of the digital PDP using the proposed algorithm was considerably reduced.