• Applied Microscopy
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• v.24 no.4
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• pp.98-106
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• 1994

The corneal formation of compound eye of Pieris rapae L., which was mostly made during pupal stage, was morphologically investigated with light microscope, scanning electron microscope and transmission electron microscope. The regeneration of the microvilli were found on the surface membranes of corneagen cells and retinular pigment cells of preommatidium after apolysis pupal cuticle. The microvilli were finally differentiated to corneal nipples of the ommatidium. The corneal cuticle was generated on the superficial layer of the preommatidium from corneagen cells and retinular pigment cells. The corneal process was also formed under the cuticular layer from the corneagen cells. The pore canal was appeared within the cuticular layer and connected with the retinular pigment cell as if the root of interommatidial hair was connected. The interommatidial hair was projected randomly among the ommatidial facets and cornal nipple was arrayed regular on the ommatidial facets. The cornea was convex lens and the refracting power by its convex shape was 4 diopter.

• 한국생물공학회:학술대회논문집
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• 2000.04a
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• pp.169-172
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• 2000

Studies on extraction of red pigment was performed to provide the basic information for the utilization of red pigment as s new source of natural food colorant. A bacterium isolated from marine resources were carried out the test for excretion of red pigment. One strain of a marine bacterium, KSR-97 showed a high production of red pigment on the medium of colloidal chitin, peptone-yeast extract with minerals. In physicochemical and sensory properties in aqueous solution of red pigment was investigated at various condition of pH, temperature, concentration of ethanol and stability of storage. Potent antioxidative of red pigment was separated by thin layer chromatograpy, silica gel chromatography and reverse high performance liquid chromatography using ODS hypersil column.

• Applied Microscopy
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• v.15 no.1
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• pp.59-70
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• 1985

Morphogenesis of rat retina was studied by light and electron microscope from day 14 of gestation to 55 days after birth. The results indicate as follows: 1. At the outer border of the neuroblastic layer at the 14th day of gestation, cells she wed active mitotic figures which result in the increases of thickness and differentiations of this layer. 2. At birth, rat retina is still in a premature state. But, it is begining to approach its adult condition in appearance till the 9th postnatal day. Particulary photosensitive cells are fully developed by the 14th postnatal day, so they are functional from now on. 3. It is observed that the pigment epithelium begins differentiation at the fetal period, but is not functional urtil birth 4. The pigment epithelium differentiates earlier than the neuroblastic layer. It is suggested that these two layers are so closely associated that the pigment epithelium takes part in the differentiations of the neuroblastic layer. In conclusion, rat retina is differentiated soon after the optic cup formation before the 14th day of gestation, but even new born rat retina is not functional, and then it has function as photoreceptors coincided with the eye opening.

• Applied Microscopy
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• v.28 no.4
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• pp.503-512
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• 1998

Fine structure of the cutaneous pigments in the black widow spider, Latrodectus mactans are studied with light and electron microscopes. The cutaneous pigments are only observed in epidermal layer just beneath the cuticle. These pigments are compactly distributed around the spinnerets which located at caudal area of the abdomen. According to the fine structural characteristics of the pigment granules, two main types of guanine pigment granules-carotenoid vesicles and reflecting platelets - are observed in the cytoplasm of the epidermal cells. Morphological features of these pigment granules are characterized as the electron dense carotenoid vesicles and the electron lucent reflecting platelets. Marginal electron density of the carotenoid vesicle is different from that of internal region, whereas the reflecting platelets have laminated crystalline granules. Typiral structures of these pigment granules are very similar to those of invertebrate's chromatophores, especially erythrophores and iridophores. Moreover differentiation of these pigment granules are also originated from the small vesicles of Golgi complexes similarly to those of cutaneous chromatophores.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.28 no.2
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• pp.174-182
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• 1995

Using the optical data from the EUMELI 3 and 4 missions, the optical properties are discussed in relation to primary production in the oligotrophic zone of the Eastern Atlantic Ocean. The depth of euphotic layer $(Z_{eu})$, the total accumulated concentration of pigment $(C_{TOT})$ and the concentration of pigment (C) are 88m, $12.4mgm^{-2}\;and\;0.14mgm^{-3}$, respectively for the EUMELI 3 mission and 101.7m, $10.0mgm^{-2}\;and\;0.10mgm^{-3}$, respectively for the EUMELI 4 mission. The concentration of pigment is higher in autumn (EUMELI 3) than in spring (EUMELI 4). This indicates that the concentration of photosynthetic pigment has a close correlation with vertical attenuation coefficient $(K(\lambda))$ that changes seasonally in the euphotic layer. While the spectral distributions of downward Irradiance$(E_d)$ for the wave length of 470nm increase with depth, those of upward irradiance $(E_u)$ for the wave length range between 410nm and 490nm are constant, because the study area is covered with the blue and clear oceanic deep waters. The vertical attenuation coefficients of downward irradiance $(K_d)$ and upward irradiance $(K_u)$ have low values between 0.02 and $0.06m^{-1}$ due to the low absorption and scattering by the photosynthetic pigment of phytoplankton. Therefore this zone has the characteristics of the case 1 waters with low concentrations of photosynthetic pigment, and can be classifed into IB.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.16 no.5
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• pp.222-226
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• 2006

Effects of a carboxylated styrene-butadiene-based liquid additive on the microstructure, mechanical strength and decolorization resistance of inorganic pigment layer in the color block have been examined. More dense inorganic pigment layer characterized by lower apparent porosity, lower water absorption and uniform pigment distribution has been achieved by incorporation of a liquid additive. Also significant enhancements in the mechanical strength and decolorization resistance have been observed.

• Korean Journal of Ichthyology
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• v.17 no.4
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• pp.248-254
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• 2005

Integumentary structure of the amberjack, Seriola dumerili, was examined by light and transmission electron microscopy. Integument of the amberjack consists of epidermal and dermal layers. The epidermal thickness is about $28.32{\mu}m$. The epidermal layer could be classified into superficial, intermediate, and basal layers by morphology and position of the supporting cells. Secretory cells of the epidermal layer were classified into mucous cells and club cells in the amberjack. Mucous cells contained acidic mucous and were alcian-blue positive with AB-PAS (pH 2.5) reaction. The club cells contained well-developed rough endoplasmic reticula and large central vacuole. Also, filament-rich cells were identified in the epidermal layer. The dermal layer consists mainly of collagenous fiber, and it contains fibrocytes and pigment cells. The cytoplasm of fibrocyte had a well-developed rough endoplasmic reticulum. The pigment cells contained electron-dense melanin granules.

• Applied Microscopy
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• v.20 no.2
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• pp.12-22
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• 1990

The morphological characteristics and changes of the foregut in the grasshopper (Oxya sinuosa Mistshenko) have been studied with the special reference to the developmental stage. In light microscope level, the epithelia are seen the cuboidal shape in the 5th instar nymph and the adult. A number of pigment granules are appeared in the cuboidal epithelium of the 5th instar nymph, however the pigment granules were a few in the adult. Indistinct or undifferentiated folds of the epithelial layer were appeared in the 5th instar nymph, whereas the well-developed folds were in the adult. The well-developed muscular layers are seen in the 5th instar nymph, however in the adult the muscular layers are appeared thin or a few layer except the crop. In electron microscope level, in the foregut epithelium, a few round or oval shaped mitochondria, well-developed rER, Golgi complex, lysosome and a number of vacuoles were appeared in the cytoplasm. Two types of pigment granules, electron dense or homogenous and low electron dense or lamellar profiles, are seen in the esophageal epithelium. The crystalline profiles and plasma membrane infoldings were also appeared. In the foregut epithelium of the 5th instar nymph, however the cell organelles were generally undifferentiated and in the crop two types of pigment granules as the adult esophageal epithelium were also found.

• Journal of Conservation Science
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• v.35 no.6
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• pp.664-669
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• 2019

Yeonpyo-beob is a method of manufacturing pigments using bamboo trunk and glue solution. Glue solutions of concentrations 1, 5, and 10% were employed to manufacture pigments, and the characteristics of pigment manufacturing were analyzed according to these concentrations. The pigment manufacturing process can be divided into holding and drying phases. The holding phase involves the sedimentation of relatively large particles, whereas the drying phase involves the sedimentation of small particles. The layers formed during the drying phase have almost similar forms regardless of the concentration of the glue solution. If the concentration of the glue solution is low in the holding phase, the particles are mixed and the formation of a layer is difficult. In contrast, when the concentration of the glue solution is higher, the layer of the pigment is more distinct. These results confirmed that the differences in viscosity due to the variation in the concentration of the glue solution affect the sedimentation velocity of the pigment particles, thereby affecting the formation of the layer of the pigment and the pigment manufacture. Consequently, applying 10% glue solution to reduce the sediment velocity is deemed suitable for the stratification of the pigment particles and the manufacture of pigments.

• Journal of Conservation Science
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• v.35 no.6
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• pp.573-587
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• 2019

In this study, reproducing specimens were made from mixing domestically produced magnetite, clay and non-plastic raw materials to reproduce the pigments used in the manufacture of traditional cheolhwa buncheong stoneware. In order to reveal the color fomation of glaze, 30 specimens with good color development were analyzed scientifically. Magnetite, which is the main raw material of the pigment, is a pigment capable of creating a dark black color in a reducing environment at 1,200℃. However, it reacts with the additionally added lime component and discolors to greenish yellow color in oxidizing environment at 1,230℃. Hematite is not significantly affected by the firing temperature and environment, but develops a dark black color when mixed with clay with iron content of more than 10%. The fluidity of the pigment is determined by R₂O₃/RO₂ value, which also affects the color development. In the microtexture observation, the color formation of the glaze layer and the iron oxide crystals identified some differences depending on the particle size of the pigment and the firing environment. Reproduced specimens made of magnetite are present in the form of aggregates of iron oxide in the interface between glaze layer and slip layer in the oxidizing environment at 1,200℃. However, in the reducing environment, aggregates of iron oxides do not exist in the reproduced specimens, and they are homogeneously distributed in the glaze layer and formed a dark black color. In contrast, hematite-based specimens form dendritic structures in the glaze layer in an oxidizing environment and develop black.