• Korean Journal of Materials Research
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• v.27 no.2
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• pp.82-88
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• 2017

Ink-jet printing techniques with ceramic ink, which contains ceramic pigments as colorant, are in increasingly use in the ceramic industry. Generally, ceramic pigments that are produced by conventional method show diameters of several micrometers; these micrometer sized particles in the ink-jet printing process can cause undesirable behavior such as print head nozzle clogging. To prevent this problem, a particle size reduction process is required. In this study, CMYK (cyan, magenta, yellow, black) pigments were synthesized via solid state method. Each pigment particle was milled to submicron size by an attrition mill. The effects of micronizing on the morphology, mechanical property, crystal structure and color property of the CMYK ceramic pigments were investigated by field emission scanning electron microscopy (FE-SEM), particle size analysis (PSA), X-ray diffraction (XRD) and CIE $L^{\ast}a^{\ast}b^{\ast}$.

• Korean Journal of Food Science and Technology
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• v.34 no.6
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• pp.977-983
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• 2002

This study was performed to establish the precise and rapid method to distinguish croakers through the pigment analysis of colored imported white croakers for adultration. We surveyed the coloring behaviors, extraction test by water and organic solvent and using pigments such as targeting, curcumine, and azo dye products. The pigment of yellow croaker is not stained on wet cloth or tissue which is rubbed on epidermis of yellow croaker and was not eluted in water extraction test, while adulterated pigments were easily extracted by water and acetone, but edible diluted yellow, Yellow No. 4 and Yellow No. 5 were not extracted. Reactive pigment was detected easily by extraction with water and dispersed pigment was also detected by extraction test. As a result of discoloring characteristics of carotene having similar structure to yellow croaker and azo dye by oxidation and reduction, azo dyes were not discolored by oxidation with sodium percarbonate or peracetic acid but that were discolored by oxidation with Fenton reagent after 1hr and by hypochlorite promptly. On the other hand, carotenes were not discolored by sodium precarbonate and Fenton reagent but discolored by sodium hypochlorite after 2 hr and by peracetic acid promptly. Azo dyes were discolored by reduction with sodium hydrosulfite and sodium carbonate but carotenes were not discolored by these reagents. This discoloring test was applicable to detect adulterated pigments and other marine product.

• Ocean and Polar Research
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• v.34 no.2
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• pp.111-123
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• 2012

To understand the phytoplankton community in the eastern part of the Yellow Sea (EYS), in the summer, field survey was conducted at 25 stations in June 2009, and water samples were analyzed using a epifluorescence microscopy, flow cytometry and HPLC method. The EYS could be divided into four areas by a cluster analysis, using phytoplankton group abundances: coastal mixing area, Anma-do area, transition water, and the central Yellow Sea. In the coastal mixing area, water column was well mixed vertically, and phytoplankton was dominated by diatoms, chrysophytes, dinoflagellates and nanoflagellates, showing high abundance ($>10^5\;cells\;l^{-1}$). In Anma-do coastal waters characterized by high dominance of dinoflagellates, high phytoplankton abundance and biomass separated from other coastal mixing area. The southeastern upwelling area was expanded from Jin-do to Heuksan-do, by a tidal mixing and coastal upwelling in the southern area of Manjae-do, and phytoplankton was dominated by benthic diatoms, nanoflagellates and Synechococcus group in this area. Phytoplankton abundance and biomass dominated by pico- and nanophytoplankton were low values in the transition waters and the central Yellow Sea. In the surface of the central Yellow Sea, high dominance of photosynthetic pigments, 19'-hexanoyloxyfucoxanthin and zeaxanthin implies that haptophytes and cyanobacteria could be the dominant group during the summer. These results indicate that the phytoplankton communities in the EYS were significantly affected by the formation of tidal front, thermal stratification, and coastal upwelling showing the differences of physical and chemical characteristics during the summer.

• Journal of Powder Materials
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• v.23 no.5
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• pp.343-347
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• 2016

Fe-based pigments have attracted much interest owing to their eco-friendliness. In particular, the color of nanosized pigments can be tuned by controlling their size and morphology. This study reports on the effect of length on the coloration of ${\beta}$-FeOOH pigments prepared using an $NH_4OH$ solution. First, rod-type ${\beta}$-FeOOH is prepared by the hydrolysis of $FeCl_3{\cdot}6H_2O$ and $NH_4OH$. When the amount of $NH_4OH$ is increased, the length of the rods decreases. Thus, the length of the nanorods can be adjusted from 10 nm to 300 nm. The color of ${\beta}$-FeOOH changes from orangered to yellow depending on the length of ${\beta}$-FeOOH. The color and phase structure of ${\beta}$-FeOOH is characterized by UV-vis spectroscopy, CIE Lab color parameter measurements, transmission electron microscopy (TEM), scanning electron microscopy (SEM), and powder X-ray diffraction (XRD).

• Journal of Conservation Science
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• v.28 no.2
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• pp.101-112
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• 2012

The Donggwanwangmyo Shrine was built in the period of Joseon Dynasty in 1602. There are Clay Statues (Gwanwo, Jangbi, Woojanggun, Juchang, Jojaryoung and so on) enshrined in the inside of the main hall. Original color of these Clay Statues are deteriorated by inorganic pollutant like dust. And the origanal forms were damaged during several process of restorations and repaintings. This study carried out XRD, SEM-EDS, P-XRF and chromaticity measurement for characterization of pigments which painted on Clay Statues. As a result, cinnabar, hematite and red lead were used to paint in pigments for the red and brown colors. Light red pigment was made by gypsum with these minerals that make colors. Graphite and gold were used to color of black and gold pigment, respectively. Green pigment is identified of malachite, atacamite and glauconite. Blue pigment which is clearly painted on Clay Statues is interpreted a morden industrial pigment that were painted at repair work. White pigments are detected calcite, gypsum and silver white. Orpiment and litharge were used to color of yellow and light yellow pigment.

• Journal of the Korean Society of Food Science and Nutrition
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• v.18 no.2
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• pp.143-152
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• 1989

Some sugars and proteins were mixed with yellow corvenia lipids, soybean lipids or see yolk lipids to study the influence of the sugars or proteins on lipid oxidation and browning in dry and wet system during kept at $40^{\circ}C$. In the yellow corvenia lipids mixed with various food components, peroxide value(POV), carbonyl value(COV) and brown pigments were much higher than the case that soybean lipids or egg folk lipids were mixed. In terms of the food components, they appealed high in glucose, sucrose and starch but low in albumin and casein. When the soybean lipids were mixed, POV appeared low in all these maxture. COV and brown pigments appeared high in glucose, sucrose and starch but low in albumin and casein. In the case of egg york lipids, POV appeared lower than that of soybean lipids but COV and brown pigments were similar. In the starch mixture of three lipids in wet system, POV and COV in yellow corvenia lipids appealed lower, but appeared higher in soybean lipids and egg yolk lipids than those in dry system. Brown pigments appeared similarly with the case in dry system. And the all mixtures of casein in wet system, POV and COV appealed lower thanthose of the dry system, but brown pigments appeared high.

• Journal of the Korean Society of Safety
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• v.30 no.2
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• pp.14-20
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• 2015

The content of hazardous heavy metal of materials used in playground facility for children was investigated using X-ray fluorescence (XRF) and inductively coupled plasma (ICP) analyses, In order to examine the content of hazardous heavy metals according to the material color, four colors, i.e., green, red, yellow and blue, were categorized on the materials used. The highest lead content is observed in the yellow plastic samples. The yellow samples with relatively high lead content show that the chrome content is also high. This can explained that lead chromate, so-called chromium yellow, is normally used as a main pigment to express the yellow color. Therefore, it is concluded that hazardous heavy metal detected in the materials of playground facility for children is due to the pigments used for coloring. Based on above findings, the relationship between the color of materials used in playground facility for children and the content of hazardous heavy metal is discussed.

• Korean Journal of Food Science and Technology
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• v.6 no.4
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• pp.209-213
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• 1974

Pigments were extracted by aqueous acetone from the boiled canned oyster colored during storage and then the components were separated by thin layer chromatography. Totally eleven pigments could be isolated including one yellow, one red, five orange or reddish orange and four green components, and their UV-visible spectra were measured. It can be envisioned from the electronic spectral study and color reaction on the indivisual pigments isolated from the brown acetone extracts that the green pigments as well as most of the yellow orange ones may be porphyrin derivatives originated probably from the chlorophyll and some of the orange pigments contains ketocarotenoids. In particular, the pigment of band 8 which is expected to be pheophytin a or its derivatives and the carotenoid band 7 seem to be the major pigment. The close resemblance of the chromatogram of the colored muscle extract to that of the viscera suggests that the brown coloring material is probably originated from the viscera pigments.

• Korean Journal of Pharmacognosy
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• v.27 no.4
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• pp.301-308
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• 1996

Hairy roots induced from stems of Rubia cordifolia var. pratensis were cultured in the liquid medium under a variety of auxins to find the optimal condition for the growth and production of pigments. Culture of the hairy roots on NN liquid medium containing NAA 0.5 mg/l was best for growth of hairy roots. Production of yellow anthraquinone derivatives and purpurin in hairy roots was enhanced by the culture on NN liquid medium without auxins. Effects of L-phenylalanine, L-tyrosine and juglone, synthesized via the shikimic acid pathway, on growth and production of pigments in hairy roots were studied in the present study. Concentration of exogeneous L-phenylalanine. L-tyrosine and juglone in liquid culture system of hairy root containing NAA 0.1 mg/l was decreased quickly in its early stages of the culture period. Addition of juglone to NN liquid medium containing NAA 0.1 mg/l enhanced the productivity of pigments in hairy roots.

• Journal of Conservation Science
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• v.30 no.1
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• pp.13-25
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• 2014

This study interpreted the chemicals of the pigments and the coloring techniques employed on Youngsan Ritual Ceremony Buddhist Painting through a nondestructive analysis method and a microscopic observation. Based on the interpretation, this study closely examined the chemical properties of the names of the coloring materials specified on the ceremonial writing of the Buddhist painting. It is estimated that lead white was used for the white pigments, orpiment and organic pigment for the yellow pigment, cinnabar/vermilion, minium, red ochre, and red dyes for the red pigments, malachite or atacamite for the green pigments, azurite and indigo for the blue pigments, and ink stick for the black pigments. The pigment names specified on the ceremonial writing are juhong, jungcheong, hayeop, whangdan, and whanggeum, and it was verified that juhong is cinnabar or vermilion, jungcheong is azurite, hayeop is malachite or atacamite, whangdan is minium, and whanggeum is a gold foil.