• Journal of Conservation Science
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• v.38 no.1
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• pp.1-13
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• 2022

Colour consistency is an important consideration when selecting pigments used on works of art. In this study, we analyse the colour difference between two sets of synthetic blue glass pigments acquired at least 8 years apart from the same manufacturer in Japan. The old pigment set (unused, dry powder with four different grain sizes) appears faded compared to the new set. These pigments are made available for artistic use, commonly in Nihonga or Japanese paintings. Raman spectroscopy and SEM-EDS results characterize these pigments as cobalt aluminate spinels dissolved in leaded glaze, a special class of complex coloured inorganic pigments that is not well-understood in the field of conservation. Colour difference between the old and new pigments with four different grain sizes were quantified by analysing photomicrographs with image analysis software. Blue pigments with coarse and extremely fine grains showed significant colour change compared to pigments with medium and fine grain sizes. The high occurrence of crystallites in the finer grains give a final colour that is bluer and lighter. Possible causes for the colour difference including manufacturing methods and storage environment are discussed.

• Journal of the Korean Applied Science and Technology
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• v.28 no.3
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• pp.335-344
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• 2011

The pearlesent pigment has received attention in a diversity of fields like cosmetics, inks, paints and so on. Ferric Ferrocyanide, one of the nano sized pearlescent pigment, is a kind of surface modification pigment that covers a metal oxidized substance or a coloring agent with uniform thickness. Characteristics of pearlescent pigment are various interference color, intense gloss effect and a three-dimensional effect. We synthesised the pearlesent pigment that ferric ferrocyanide can be deposited on the titania/mica surface by hydrothermal synthesis method. The process parameters are concentration of precursor, controlling pH and reaction temperature. The optimun conditions is that amount of iron(III) chloride hexahydrate is 3.1 wt% and amount of potassim ferrocynide trihydrate is 3.6 wt% in the started pH 4.5 at $70^{\circ}C$. The coating rate and coating efficiency of ferric ferrocyanide was about 1.47 % and 96.7 %, respectively. The synthesised pearlesent pigment was characterized by SEM, XRD, FT-IR and EDS.

• Journal of Plant Biotechnology
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• v.36 no.2
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• pp.124-129
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• 2009

In general, the root color of Codonopsis lanceolata is white, but red or blue-colored root is found at a low frequency in nature. Red or blue-colored roots have scarcity value, thus farmers wish to produce colored roots. The factors for determining the color of roots are unclear whether the color is controlled by genetically or simply by environmentally such as soil environment. Using in vitro culture system which is advantageous for setting of the same culture condition, we analyzed the physiological and morphological characteristics and genetic differences among red-, blue- and white lines of C. lanceolata. In the red colored roots, stems of in vitro cultured plantlet were colored in dark red pigment. Histological analysis revealed that the red pigment was accumulated in the outer cortex layer of the stem and determined as anthocyanin. Chlorophyll contents in red root lines were higher than those in white- and blue root lines. Plantlets from red roots were smaller in both shoot length and total leaf area than those from white- and blue roots. Genetic differences among the three different colored C. lanceolata were determined by RAPD (Randomly Amplified Polymorphic DNA) analysis. Each line of colored roots had clear DNA polymorphism. These results indicate that the occurrence of red- and blue colored roots in nature was determined by genetic factors rather than soil enviromental conditions.

• Journal of Ginseng Research
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• v.21 no.1
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• pp.28-34
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• 1997

The effects of light on the pigment production and chloroplast development were examined on ginseng hairy roots cultured in 1/2MS liquid medium. The chlorophyll and carotenoid production were increased from 1,000 to 3,500 lux condition, but decreased drastically in 7,000 lux condition. The anthocyanin production was significantly increased with increment light intensity(1,000∼7,000 lux). The thylakoid membrane of chloroplast was proplastid in dark condition and it began to develop into thylakoid membrane in 1,000 lux condition and then intact thylakoid membrane was developed in 3,500 lux condition. However, the development of thylakoid membrane in 7,000 lux condition was inhibited comparing to 3,500 lux condition. The total chlorophyll production in blue light condition were high comparing to other wavelength and same as 40% of total chlorophyll on white light(3,500 lux) condition. The chlorophyll and carotenoid production by sucrose concentration were high in 3% sucrose condition and anthocyanin production was high in 4% condition. The production of chlorophyll and carotenoid by light periods was high when explants were cultured in dark condition for 1 week and then transferred to light condition for 4 weeks. Our results suggest that pigment production and chloroplast development could be accelerated by light Intensity of specific wavelength in cultures of ginseng hairy root.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.3A
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• pp.547-553
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• 2006

To know the effect of pigments on the material properties of color concrete, mortar and concrete tests were carried out by the using 5 kinds of pigment. The major component of red, yellow and black pigments was iron oxide and coloring component of blue and green pigments was copper phthalocyanine. Properties of mortar and concrete were some of difference according to adding ratio and kind of pigments. In case of using red, yellow and black pigments, setting time of concrete speeded a little and compressive strength was tendency to increase and slump or air content of concrete was same or decreased. On the other hand, in case of using green and blue pigments, compressive strength of concrete decreased largely because of the excessive air entrainment of surfactant and sump or air content of concrete increased highly. When the antifoaming agent was added to the color concrete mixed with green and blue pigments, compressive strength of concrete was improved and similar to that of concrete without pigment.

• Journal of the Mineralogical Society of Korea
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• v.31 no.1
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• pp.33-46
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• 2018

Traditional inorganic pigments applied to dancheong, buddhist painting, and wall painting were produced from natural minerals which were later replaced by synthetic pigments, resulting in the loss of the recipe to prepare mineral pigments. This study examined the domestic occurrence and mineralogical characteristics of green and blue mineral pigments required for the conservation of cultural heritage. Cuprous green-blue mineral pigments were found as the weathering products of waste dumps and ores of abandoned Cu-Pb-Zn sulfide mines. Mineralogical analyses using X-ray diffraction and scanning electron microscopy identified diverse hydrous copper sulfate pigments of green (brochantite and devilline) and blue color (linarite, bechererite, and schulenbergite) with minor green pigments of antlerite and atacamite commonly associated with cerussite, smithsonite, anglesite, and cuprite. Noerok, a green silicate pigment, replaced the fractured basalt lava. Celadonite was responsible for the green color of Noerok, closely associated with opal in varying ratio. Glauconite, green silicate pigment, was identified in the Yellow Sea sediments. Malachite and azurite, the most important green and blue pigments of Korean cultural heritage, were not identified in this study.

• Journal of Conservation Science
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• v.36 no.5
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• pp.351-367
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• 2020

The pigments of three old and new celestial charts folding screens(『Celestial Chart(Folding Screen)』 and 『Old and New Celestial Charts, Eight-Panel Folding Screen』 of National Folk Museum of Korea and 『Koudou-Nanboku-Ryousouseizu』 of National Diet Library of Japan) were analyzed to estimate their dating. It was estimated that the 『Celestial Charts(Folding Screen)』 was painted using traditional pigments from the Joseon dynasty such as azurite, indigo lake, malachite, atacamite, vermilion, iron oxide, cochineal, gamboge, orpiment, lead white, talc and soot. The green and blue colors of the 『Old and New Celestial Charts, Eight-Panel Folding Screen』 and 『Koudou-Nanboku-Ryousouseizu』 were painted using artificial inorganic pigments such as emerald green and ultramarine blue. These pigments were imported from Europe post the mid-19th century. In the 『Old and New Celestial Chart, Eight-Panel Folding Screen』, only artificial inorganic pigments were used for green and blue colors. However in the 『Koudou-Nanboku-Ryousouseizu』, emerald green and atacamite in green color, and ultramarine blue and indigo lake in blue color were used together. Based on both the results of pigment analysis and the study of star charts and inscriptions, the 『Celestial Charts(Folding Screen)』 was painted post mid-18th century. The 『Koudou-Nanboku-Ryousouseizu』 and 『Old and New Celestial Charts, Eight-Panel Folding Screen』 were painted after green and blue artificial pigments were imported in the mid-19th century. The 『Koudou-Nanboku-Ryousouseizu』 in which both traditional and western artificial pigments were used, can be dated earlier than the 『Old and New Celestial Chart, Eight-Panel Folding Screen』.

• Journal of the Korean Ceramic Society
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• v.50 no.6
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• pp.510-517
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• 2013

In this study, the properties of blue inorganic nano-pigments with a spinel structure were systematically investigated. We report the preparation of a blue ceramic nano-pigment and the Co and Ni substitutional effects on the blue color. $MgAl_2O_4$ was selected as the crystalline host network for the synthesis of cobalt and nickel-based blue ceramic nano-pigments. Various compositions of $Co_xMg_{1-x}Al_2O_4$ and $Ni_xMg_{1-x}Al_2O_4$ ($0{\leq}x{\leq}1$) powders were prepared using apolymerized complex method. The obtained powder was preheated at $400^{\circ}C$ for 5 h and then calcined at $1000^{\circ}C$ for 5 h. XRD patterns of the (Co,Mg)$Al_2O_4$ and (Ni,Mg)$Al_2O_4$ samples showed a single phase of the spinel structure in all compositions. TEM results indicated nano-sized pigments for (Co,Mg)$Al_2O_4$ and (Ni,Mg)$Al_2O_4$ with a particle size ranging from 20 to 50 nm. The characteristics of the color tones of (Co,Mg)$Al_2O_4$ and (Ni,Mg)$Al_2O_4$ were analyzed by CIE $L^*a^*b^*$ measurements. In addition, the thermal stability and the binding characteristics of (Co,Mg)$Al_2O_4$, (Ni,Mg)$Al_2O_4$ are discussed in terms of the TG-DSC and FT-IR results, respectively.

• 보존과학연구
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• s.22
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• pp.93-114
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• 2001

The composition analysis of Danchung pigments at Geunjeongjeon Hall in Gyeongbokgung Palace were carried out by FXRF and MXRD. The analytical result of the inside pigments at Geunjeongjeon showed that these painted in use the mineral pigments. Gold pigment was pure gold(Au).The main composition identified in green pigments were chalcanthite($CuSO_4$.$5H_2O$) and celadonite($K(Mg, Fe, Al)_2$.$(Si, Al)_4O_10(OH)_2$ ). Red pigments werecinnnabar(HgS).The analytical result of the outside pigments at Geunjeongjeon revealed that these applied to the artificial synthetic pigment. Yellow pigment was chromeyellow($PbCrO_4$). The main composition identified in red pigments were red lead($Pb_3O_4$)and hematite($Fe_2O_3$). Green pigments were emeral green($C_2H_3A_s3Cu_2O_8$) and chromegreen($Cr_2O_3$). Blue pigment was lazurite($Na_6Ca2Al_6Si_6O_24(SO_4)_2$), titanium dioxide($TiO_2$) of white pigment.

• Applied Biological Chemistry
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• v.23 no.1
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• pp.73-83
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• 1980

The light harvesting pigment proteins of dinoflagellates exhibit essentially 100% efficient energy transfer from carotenoid (peridinin) to chlorophyll a within the antenna pigment complexes. The high efficiency of solar energy harvesing (particularly blue light) for photosynthesis in dinoflagellates is attributable to the unique molecular topography of peridinin and chlorophyll e within the protein crevice. The mechanisms of energy transfer from carotenoids to chlorophyll in higher plants have also been discussed in comparison with the dinoflagellate antenna pigment complexes. As an example of solar energy harvesting, particularly red light, for photosynthesis in algae, the molecular topography and energy transfer in the photosynthetic accessory pigment protein, Chroomonas phycocyanin, have also been discussed.