• Journal of the Korean Chemical Society
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• v.40 no.2
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• pp.32-152
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• 1996

• Korean Journal of Food Science and Technology
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• v.12 no.1
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• pp.41-44
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• 1980

The model compounds of Vitamin $B_1$ 3-benzyl-4-methylthiazolium bromide, (1), 3, 4-dimethylthiazolium iodide (2) and 2-($\alpha$-hydroxyethyl)-3-benzyl-4-methylthiazolium bromide (3) were prepared by the organic synthesis. Colorimetric determination with phosphotungstic acid showed an increase of $1.1{\sim}1.2$ folds with compound (1) and $1.5{\sim}1.9$ folds with compound (3) when readings were carried out after an overnight, compared with immediate readings. Colorimetry with 2.6-dibromoquinone chloroimide yielded the compound (1) being $2.2{\sim}2.5$ folds higher than the compound (3). The half wave potentials and diffusion currents of anodic and cathodic waves of polarography with the same concentration of the compounds (1), (2) and (3) also resulted in different values of their waves. Therefore, it was a firm conclusion that any values obtained from quantitative analysis with this model compounds (1), (2) and (3) were not directly applicable to those of $B_1$.

• Korean Journal of Food Science and Technology
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• v.29 no.1
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• pp.21-25
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• 1997

Application of the color indicators to kimchi packages was investigated in order to monitor the ripeness of commercial kimchi products during storage and distribution. Kimchi was packed in polypropylene (PP) tray and nylon/cast polypropylene (Ny/CPP) lid where the indicating sachet consisting of $CO_2$ absorbent and chemical dye (bromocresol purple and methyl red) was attached. The ripeness of kimchi during storage at $0{\sim}20^{\circ}C$ was measured in terms of pH and titratable acidity (TA), which were compared with Hunter color values of the indicators. The color of bromocresol purple dye turned from light blue to purple, while that of methyl red turned from light yellow to red. Regardless of the storage temperatures, Hunter b values of bromocresol purple type and Hunter a values of methyl red type appeared to be proportional to both the pH and TA values of kimchi. These results suggest that the color indicators be employed as one of the effective techniques for sensing the ripeness of packaged kimchi products without destructing the package.

• Fashion & Textile Research Journal
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• v.19 no.5
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• pp.646-652
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• 2017

In order to clarify an availability of water treatment for persimmon extract dyeing, effect of color developing by water treatment process on cotton fabrics dyed with persimmon extract was investigated. Dyed fabrics were dipped still water and circulation water in various temperature. Concerning water color developing, still water color developing and circulation water color developing have been examined, and the temperature of water has been apprehended to prepare an effective basis of water color development. The surface color based on circulation water color development displays low values of $a^{\ast}$ and $b^{\ast}$, and the range of the c value(Munsell chroma) is narrow and has the value of 2 to 3, thus displays the coloration of a dark tone. The effect of temperature in water color development was insignificant, due to the small difference in temperature from $20^{\circ}C$ to $40^{\circ}C$. At $80^{\circ}C$, remarkable color development manifested, which is evidence of the high influence of temperature. The effects of circulation were clear at low temperatures, and the effects of temperature highly manifested at high temperatures. Circulation water color development display great color development at all temperatures to allow industrial color development with the absence of sunlight, thereby having an effect of energy reduction and developing color in dark tones, however this also is a strength of persimmon extract concerning color diversification, and is judged to have great value of industrial and practical application.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.27 no.4
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• pp.154-161
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• 2017

$Zn_2TiO_4$, which is a progenitor of zinc crystallization, plays a significant role in controlling the crystallization of willemite ($Zn_2SiO_4$) in forming glaze at low temperatures. Thus, $Zn_2TiO_4$ was used to formulate stable willemite and to gain structural control. When synthesized 15 wt% of $Zn_2TiO_4$ is added to engobe and then applied, it can manipulate its crystallization and location. Additionally, when colorant is added to $Zn_2TiO_4$ and then applied to engobe, the mixture's colorant effect can be shown at crystallization. Certain characteristics of synthesized $Zn_2TiO_4$ enable various engobes to be applied to clay bodies. With a single glazing, the crystallization, location, and color of the crystals can be discretionarily regulated.

• Journal of the Korean Society of Tobacco Science
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• v.2 no.2
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• pp.38-43
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• 1980

The spectrophotometric determination oi reducing sugar in the tobacco leaves was carried out by employing blue tetrazolium chloride as a color developing reagent. The absorption maximum of formazan dye which is the product of the reaction between blue tetrazolium chloride and fructose was shown to be $530^{nm}$. In the fructose concentration range of 0.02mg/ml-0.14mg/ml the calibration curve was well coincided to the law of Beer-Lambert. In order to take a look at the accuracy and/or recovery rate of fructose determination, the standard fructose was added to the tobacco leaves and the concentration of this standard fructose was estimated. A tittle lower concentration of the standard fructose compared with the pure one in solution was observed. However, an excellent analytical recovery was revealed under the -2% of relative error limit. When we carried out the quantitative determination of this reducing sugar by the method of visual read-out (without using the spectrophotometer), the relative error was obtained to be $\pm$10%.

• Journal of the Korean Wood Science and Technology
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• v.23 no.4
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• pp.108-116
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• 1995

This experiment was conducted to screen a superior wood-rotting fungi for lignin degradation and ligninolytic enzyme production by evaluation of red colored zone width on potato-dextrose agar medium and oak woodmeal medium complimented guaiacol. Relationship between the red colored zone width on GU-WA medium and klason lignin loss on woodmeal medium showed the positive correlation. Thus, the potential ligninolytic activity of wood rotting fungi which are not elucidated yet may be estimated to some extent by the evaluation of the red colored zone width on GU-WA medium. Of the isolates screened from fruit bodies and decayed woods. LKY-12, LKY-7 and C. versicolor-13 isolates having preferential lignin degradation and laccase activity were selected. These isolates exhibited characteristics of superior wood-rotting fungi as Klason lignin loss ranged from 30% to 35% and ligninolytic enzyme activity of these isolates on glucose-peptone broth was higher than that of other isolates. And then, these isolates were considered to be able to use in biological pulping and bleaching and ligninolytic enzyme production.

• KSBB Journal
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• v.15 no.2
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• pp.145-149
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• 2000

Methyl mercaptan oxidase was isolated and purified from Thiobacillus thiooxidans KCTC2505 for the detection of mercaptans. T The produre of purification involved DEAE-Sephacel and Superose 12 column chromatographies with recovery yields of 40 a and 6.3%, and specific activity of 19.7 and 80.1 units/mg-protein, respectively. The molecular weight of purified methyl m mercaptan oxidase was determined to be 68.1 kDa by SDS-PAGE. The extract from DEAE-Sephacel column chromatography h had a high activity in oxidizing methyl mercaptan to produce formaldehyde which can be easily detected by purpald-coloring m method. Optimum temperature for activity was observed at $43^{\circ}C$. This enzyme was activated by $NH_4CI and (NH_4)_2S0_4$, and | inhibited by KCI and NaC!.

• Journal of the Korean Chemical Society
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• v.33 no.3
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• pp.304-308
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• 1989

The spectrophotometric determination of $Lu^{3+},\;Eu^{3+}$ and some other rare earths have been investigated using Methyl Thymol Blue(MTB) as spectrophotometric reagent. Rare earth elements form a stable complex with MTB abount pH 6.5 and the ratio of its complex is 1 to 1. MTB has a absorption maxima at 440nm and rare earth MTB complex has absorption maxima 610nm at pH 6.5, respectively. The absorbance of the rare earth MTB complex is stable in 7 hours after color developing and obey the Beer law in the range of $0{\sim}110{\mu}g/50ml$. The ligand such as phosphate, citrate and EDTA decrease the absorbance of its complex considerably, and this method has a poor selectivity of each rare earth element and the molar absorptivity is $1.2{\sim}2.0{\times}10^4mol^{-1}{\cdot}l{\cdot}cm^{-1}$. In methyl alcohol, ethyl alcohol and acetone medium we did not find out any absorption change of the rare earth MTB complex.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.16 no.1
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• pp.25-31
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• 2006

Many amethysts of different origins such as South America, Aftrica, and Asia were compared. According to ICP-AES analysis, the colorizing elements were Fe, Cr, Cu, and Co. Amethysts from South America showed higher concentrations of the elements. UV- VIS analysis showed that both natural and synthetic amethysts were characterized by the higher absorption at 350 nm and 550 nm wavelength. The natural amethysts had lower permeability than that of the synthetic amethysts. According to FT-IR analysis, the synthetic amethysts were distinguished from the natural amethysts in that they had a typical absorption band of $3543cm^{-1}$. The amethyst from South America showed strong absorption bands of $3584cm^{-1}\;and\;3435cm^{-1}$, and African amethyst had absorption bands of $3299cm^{-1}\;and\;3196cm^{-1}$. $3381cm^{-1}$ absorption band was shown strongly for Asian origins.