• Journal of Conservation Science
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• v.29 no.1
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• pp.35-45
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• 2013

The Clay Statues of Donggwanwangmyo Shrine (Treasure No. 142) are highly damaged physical weathering which are crack, exfoliation. Pigment of surface are discolored by chemical weathering like dust. The result of ultrasonic velocity measurement, low velocity zone was measured the lowest part of Woojanggun Statue. Deficiency condition of pigment layer was evaluated quantitatively through infrared Thermography. As a result, exfoliation part was detected at high temperature. Making techniques of the Clay statues were identified by gamma rays, infrared TV, SEM. All Clay Statues were founded on wood base and joints of wood were fixed using thin iron wires. After wood base was twisted a straw rope, it was made by clay. Clay was blended with rice straw to prevention of crack and exfoliation. The upper side of clay layer was coated with Hanji(Korean handmade paper) and cotton in order to isolate the pigment layer.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.2
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• pp.162-168
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• 2010

This study attempted to clarify the difference in eggshell pigmentation between blue-shelled ducks (BSD) and whiteshelled ducks (WSD). The eggshell pigmentation deposition process is discussed. Ultraviolet spectro-photometer and HPLC were used to determine the biliverdin concentration in the shell gland, uterus liquid and eggshell at 6, 12, 18, 20, 23.5 h post-oviposition. The biliverdin concentration in the eggshell and uterus fluid showed significant differences between BSD and WSD, but not in the shell gland. The heme oxygenase activity in the shell gland of both kinds of ducks remained mostly constant during the ovulatory cycle with no variation. The assay of exogenous biliverdin injection into the shell gland antrum in the WSD indicated that exogenous biliverdin could be deposited continuously into the eggshell until the source was exhausted. A layer-by-layer dissolution assay was used to examine the eggshell pigment deposition process. The biliverdin concentration in the first to sixth layers of the eggshell in the BSD was significantly higher than that in the white-shelled counterpart. The blue pigment concentration increased persistently from the 6th layer to the $1^{st}$ layer. The BSD eggshells did not accumulate a large quantity of biliverdin in the most external layer. They tended to increase the deposition layer by layer. Our results demonstrated that different BSD and WSD eggshell colors were influenced by the amount of biliverdin in the uterus fluid and not determined by the amount of biliverdin in the shell gland. This implies the existence of a mechanism that controls biliverdin transportation from the shell gland into the uterus fluid, thereby playing a key role in regulating duck eggshell color.

• Journal of Conservation Science
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• v.33 no.6
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• pp.507-518
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• 2017

Through a combination of scientific analytical methods, the coloring materials used in $20^{th}$ century paintings in historical churches of Baclayon, Dauis and Loay, which are municipalities in Bohol, Philippines, were studied. Inorganic pigments were identified using SEM-EDS and XRD. Iron-based pigments were commonly found in the paintings, yielding dark yellow and brown colors. Zinc oxide was identified as the white pigment in the ceiling paintings of Dauis Church and Loay Church, while titanium dioxide was detected in the column painting in Baclayon Church. Organic analysis showed the presence of Pigment Yellow 3, a synthetic organic pigment. Paint layers, as well as other components of the samples such as grounds and metal leaves, were examined microscopically. It was observed that different types of grounds were applied on different types of surfaces. Moreover, organic pigments were found in combination with white extender materials. Microscopic examination also revealed alterations in the artworks, such as the overpaint layer found in the samples from Baclayon Church cornice and the imitation metal leaf layers applied over the original gilt surface in the Loay Church retablo.

• Journal of Conservation Science
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• v.27 no.3
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• pp.269-276
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• 2011

We have suggested effective P-XRF analysis method for pigment painting layer by calculating penetration depth of X-ray. This experiment calculated that X-ray generated from P-XRF was possible penetration until 1.17mm deep in the pigment painting. Based on the experimental results, analysis for eight color pigments on wall paintings in Ssanggyesa Main Hall, most pigments were painted traditional pigments. However pigments on recently restorated wall painting were used synthetic modern pigments.

• Journal of Conservation Science
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• v.33 no.5
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• pp.355-362
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• 2017

The Nongso tomb of Sunchang was built in a relatively deep place; hence there was little damage from grave robbers. The tomb was completely filled with a large amount of charcoal, and therefore the wooden coffin was excavated in relatively good condition. On the basis of the structure of the tombs, excavated artifacts, and radiocarbon dating results, the tomb is estimated to be from between the late Goryeo and the early Joseon period. The wooden coffin excavated is double-layered structures consisting of an outer coffin and an inner coffin. The outside of the wooden coffin is thickly lacquered and decorated with yellow letters and white motifs. An analysis of the pigments' components revealed that the major component of the letters was gold (Au) and the major component of the motifs was silver (Ag). The coffin lacquer had three layers: a pigment layer, a yellowish-brown layer, and a black layer. The wooden bases of the coffins were painted with a black substance, such as soot, as mineral elements were not detected in the black layer. The yellowish-brown layer is presumed to be refined lacquer. From the analysis of the structure of the layers and pigments, we can estimate the method was adopted for making lacquer for wooden coffin. It is assumed that the method used gold leaf and gold powder. The form of the pigment and the internal structure are likely to be gold leaf, but the shape of the surface letters appears to have been formed using gold powder. This study will serve as important information for understanding lacquer making techniques at the time of the tombs' construction by confirming the making method through reproduction experiments using gold leaf and gold powder.

• Corrosion Science and Technology
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• v.6 no.4
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• pp.206-210
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• 2007

Aerospace aluminum alloys such as Al alloy 2024-T3 and 7075-T6 are subject to localized corrosion due the existence of intermetallics containing Cu, Mg or Zn. Chromate is currently widely used in the aerospace industry as the corrosion inhibitor for these alloys. However, chromate needs to be replaced due to its strong carcinogenicity. In this study, an extensive pigment screening has been performed to find replacements for chromates. Different categories of inhibitors were evaluated by immersion tests, DC polarization tests and other methods. Phosphates, zinc salts, cerium salts, vanadates and benzotriazole were found to be effective inhibitors for AA7075. Among those inhibitors, zinc phosphate was found to be the most effective in our novel, silane-based, one-step aqueous primer system. The performance of this primer is comparable to that of currently used chromate primers in accelerated corrosion tests, while it is completely chromate-free and its VOC is about 80% less than that of current primers. Studies by SEM/EDS showed that the unique structure of the superprimer accounts for the strong anti-corrosion performance of the zinc phosphate pigment. The self-assembled stratified double-layer structure of the superprimer is characterized by a less-penetrable hydrophobic layer at the top and a hydrophilic layer accommodating the inhibitors underneath. The top layer functions as the physical barrier against water ingress, while the lower layer functions as a reservoirfor the inhibitor, which is leached out only if the coating is damaged by a scratch or scribe. The presence of a silane in the primer further improves the adhesion and anti-corrosion performance of the primer.

• Applied Microscopy
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• v.31 no.4
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• pp.325-331
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• 2001

Integumentary structures of the stone flounder, Karefus bicoloratus were examined by means of the light and transmission electron microscopy. Stratified epidermal layer consists of supporting cells, unicellular glands and granular cells. The epidermal layer could be classified into superficial, intermediated and basal layer by morphology and structure of the supporting cells . The cytoplasm of supporting cells is divided into cortex and medullar part. In the cortex microfilaments are well developed. Mucous cells of unicellular gland were observed in the superficial and intermediated layer of the epidermis. The mucous materials were identified as glycoprotein of neutral and carboxylated mucosubstance by histochemical methods. Club cell has well developed smooth endoplasmic reticula and Golgi complex in the cytoplasm. Granular cells were observed in the intermediated and basal layer, and the cytoplasm is occupied with membrane-bounded granules of electron dense. Three types of pigment cells could be distinguished with electron density of cytoplasmic inclusions. Nerve myelins were observed near the pigment cells.

• Journal of Environmental Health Sciences
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• v.36 no.3
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• pp.236-246
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• 2010

In preparative anti-corrosive coating experiments, polyaniline was obtained by reacting an oxidizing agent with the monomer aniline. Further, the primer coating was prepared using a variety of widely-used materials such as urethane resin. For the top coating, epoxy resin and acrylic urethane resin were used. Characteristics of the coatings were assessed according to KS and ASTM specifications, and the structure of the polyaniline was characterized using FT-IR and TGA. For analysis of anti-corrosive properties in salt-spray experiments, measurements of the oxidation state of iron and surface atomic analysis were conducted using XPS and SEM-EDX. Unlike general anti-corrosive coatings which exhibit anti-corrosive effects only as a primer coating, the anti-corrosive coatings using polyaniline as the anti-corrosive pigment showed a marked synergistic effect with the top coatings. In other words, the top coatings not only produce a fine view effect, but also increase, through interaction with the primer coatings, the resistance to diffusion of corrosive factors from the external environment. It was also found that, unlike the heavy metal oxide-forming layer of the passive barrier alone, the polyaniline anti-corrosive pigment oxidized iron at the interface with the iron substrate to form a passive barrier in the oxidic layer, and itself formed a potential barrier layer with anti-corrosive factors from the external environment. Although the passive layer was damaged, the damaged area did not become completely oxidized iron; on the contrary, it showed a tendency to reduction. This can be interpreted such that a passive layer is formed again on the damaged area, and that at the same time there is a tendency to self-healing.

• Journal of Conservation Science
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• v.11 no.1 s.14
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• pp.38-51
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• 2002

The first priority we face in the conservation of wall paintings, is the conservation of painting layer. The 'painting layer' is sometimes called the pigment layer, and refers to the painted surface. For the consolidation of this painting layer we use 'fixative'. Fixative is a common adhesive which has been used in various field and conservators have made up for the weak points in the consolidation of wall paintings. In my thesis, I will summarise the range of use, standards of selection, and results of research on the use of fixative in the conservation of European paintings. In addition, I will describe various kinds of our traditional fixatives. As synthetic resins have proved that it is not ideal as a fixative for wall painting, conservators have studied to find an alternative. Same as European conservators, Asian scientists has researched to find alternative fixative which is more suitable to the wall paintings in Asia based on their traditional techniques and materials. Therefore, 1 have studied to find an adequate fixative for our own wall paintings and I could conclude that we can consider traditional fixative which is made of 'seaweeds' as an alternative and it is very important to proceed research and experiment on this material.

• Conservation Science in Museum
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• v.2
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• pp.69-76
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• 2000

This study, a part of scientific analysis of the 23 Neolithic red earthenwares excavated from southeastern coast and islands. We analyzed earthenware through statistical method and hardness analysis of clay, following the analysis of clay composition, its firing temperature, pigment composition and its thickness. Clay composition was analyzed by using ICP-AES and XRF, and then Principal Component Analysis (one of multivariate methods) was used for classification. As a result, clay of the earthenware was classified into 3 groups(Bumbang, Youkjido and other sites). In addition, hardness analysis of pigment and clay based on the depth of earthenware surface showed that pigment layer containing lots of Fe₂O₃ had higher hardness than clay part, which can be interpreted that Fe₂O₃ contributes to raising hardness in case of high temperature firing. The fact that pigment hardness is higher than that of clay part implies that pigment was applied before firing.