• Korean Journal of Medicinal Crop Science
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• v.2 no.2
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• pp.121-126
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• 1994

This experiment was carried out in the field to investigate the effects of sowing time, mulching materials and planting density on the growth and root yield of Peucedanum japonicum. The optfimum planting time for yield increase at Kyungbuk area whether the plant was grown under non-mulching or black P. E. mulching condition. Black polyethylene (P. E) film mulching was effective to promote emergence and growth, and dry root yield in the P. E. mulching was 10% higher than that in the non-mulching condition. The yield in the $20{\times}15cm$ planting density was 50% higher than that in the conventional $30{\times}20cm$.

• The Korean Journal of Malacology
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• v.27 no.3
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• pp.159-165
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• 2011

The anatomy and ultrastructure of the digestive diverticulum of Saxidomus purpuratus were described using light and electron microscopy. The digestive diverticulum of dark green color was situated on the gonad and connected to stomach by a primary duct. Digestive diverticulum is composed of numerous digestive tubules. The epithelial layer of digestive tubule, which is simple, is composed of basophilic cells and digestive cells. Basophilic cells are columnar in shape, and the electron density is higher than that of the digestive cell. The cytoplasm has a well-developed endoplasmic reticulum, tubular mitochondria, Golgi complex and membrane-bounded granules of high electron density. Digestive cells are columnar in shape, with development of microvilli on the free surface. Pinocytic vasicles, lysosomes and numerous mitochondria were observed in the apical cytoplasm of digestive cells. The results of this study suggest that basophilic cells and digestive cells in the digestive tubule are specialized in the extracellular and intracellular digestions, respectively.

• The Korean Journal of Malacology
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• v.30 no.1
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• pp.51-56
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• 2014

Morphology and histochemistry of gill of the abalone, Haliotis discus hannai were described using light microscopy and scanning electron microscopy (SEM). The abalone has bipectinate gill of protobranch. The cilia and microvilli were well-developed on the free surface of the gill filaments. The epithelial layer of gill filament was simple and composed columnar epithelia and mucous cells. Result of AB-PAS (pH 2.5 and 1.0) and AF-AB (pH 2.5) reaction showed that mucous cells contained mainly acidic carboxylated mucosubstances.

• Korean journal of applied entomology
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• v.48 no.2
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• pp.159-164
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• 2009

A taxonomic review of a new record, Bolitophagiella pannosa (Lewis) in Korea is presented. Description of adult is presented and also we conducted laboratory and field observations of the life history and fungal hosts of the darkling beetle, Bolitophagiella pannosa (Lewis). A fungivorous tenebrionid beetle, Bolitophagiella pannosa (Lewis), was a rare inhabitant of fungi on deciduous trees (Quercus, Robinia pseudoacacia etc.) in Korea. Development from egg to adulthood took 3${\sim}$10 months in nature and about 54 days in the laboratory at 25.5${\sim}$$26.1^{\circ}C$ and 63.5${\sim}$64.5% relative humidity. Both larvae and adults overwintered in their host fungi or beneath the bark of the host tree near the host fungi. Sporophores of Perenniporia medulla-panis (Fr.) Donk and Perenniporia frazinea (Fr.) Ryv. were obligate feeding and breeding sites in Korea. Description, habitus photographs of adult and instar, and illustrations of diagnostic characters are provided.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.21 no.2
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• pp.170-178
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• 2010

In this paper, we propose the modeling of the power/ground plane which includes complex dielectric permittivity and loss tangent for the power/ground coupled noise. In order to estimate the effects of the dielectric substrate for the coupled noise, we used full-wave simulators, HFSS(High Frequency Structure Simulation) and MWS(MicroWave Studio). The simulated results for the commercial substrates are compared with the measured values. TLM(Transmission Line Method) was used for the calculation of power plane impedance using Debye model which depicts the dielectric loss of PCB. Finally, impedance from proposed circuit model showed very good coincidence to the measured data.

• Journal of the Korean earth science society
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• v.37 no.1
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• pp.1-10
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• 2016

Four entities of the Cenozoic fish fossils were discovered in the Miocene Duho Formation, Pohang, Korea. these fossils were identified as the first Pleuronectiformes in Korea based on the following-the presence of postcleithrum, the elongation of the first proximal pterygiophore of the anal fin ray, almost consistent presence of two proximal pterygiophore of the anal fin rays between the two adjacent hemal spines, the fusion of the first and second hypurals, the fusion of the third and fourth hypurals and the first preural centrum, the presence of well-developed anteriormost plate-like neural spine, the presence of the urohyal like fish-hook and its elongated sciatic part, and the division of the parahypural from the first preural centrum. On the other hand, geological studies about the Duho Formation consistently claimed that shallow-sea creatures were washed away by meteorological events such as a great flood and deposited at the bottom of deep-sea by the turbidity current. However, in Duho Formation, only shallow-sea ones have been discovered thus far. This study reported that Flat fish, deep-sea creature, was discovered in Duho Formation for the first time in Korea.

• Korean Chemical Engineering Research
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• v.46 no.2
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• pp.274-278
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• 2008

Hard coating solutions were prepared from glycidoxypropyl trimethoxysilane (GPTMS) and methacryloxypropyl trimethoxysilane (MPTMS) precursors with different molar ratios of 10:0, 9:1, 7:3, 5:5, 3:7, and 0:10, respectively, by the sol-gel method. The polycarbonate (PC) sheets were spin-coated, and cured at $130^{\circ}C$ for 3 h. The effect of the GPTMS:MPTMS molar ratios of the mixture was investigated on the properties of coating films. The highest pencil hardness and adhesion to PC sheets of coating films were found for solution with GPTMS:MPTMS molar ratio of 5:5. Also, the pencil hardness of coating films was increased with increasing the $H_2O$ content in the coating solutions.

• Korean Chemical Engineering Research
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• v.47 no.4
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• pp.430-435
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• 2009

Spiropyran-doped organic-inorganic hybrid coatings were prepared starting from glycidoxypropyl triethoxysilane and vinyltriethoxysilane by a sol-gel method. They were applied as a thin layer to polycarbonate sheets and their photochromic properties were investigated. The effect of polarity of solvents dissolving the spiropyran was investigated on the photochromic properties. The decoloration rate of the spiropyran decreased with increasing the polarity of solvents dissolving the spiropyran because the open form of the spiropyran was easily stabilized in the polar gel matrix.

• Korean Chemical Engineering Research
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• v.54 no.6
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• pp.767-774
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• 2016

Three different alumina sols were prepared by hydrolyzing aluminum isopropoxide as a starting material in methanol solvent, followed by peptizing with acetic acid, nitric acid or hydrochloric acid as a peptizing agent by the Sol-Gel Method. Also, coating solutions were obtained by adding a silane coupling agent, (3-glycidyloxypropyl) trimethoxysilane to the alumina sols, deposited on polycarbonate substrates by dip-coating and densified by thermal curing. The effect of types of peptizing agents was studied on the properties of coating films. As a result, coating films, prepared with hydrochloric acid or nitric acid as a peptizing agent, showed excellent properties of pencil hardness of H or 2H and adhesion of 5B. On the other hand, coating films, prepared with acetic acid as a peptizing agent, exhibited poor properties of pencil hardness of HB and adhesion of 3B.

• Journal of the Korean Electrochemical Society
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• v.15 no.3
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• pp.154-159
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• 2012

Structural volume change occurring on the Si-based anode battery materials during alloying/dealloying with lithium is noticed to be a major drawback responsible for a limited cycle life. Silicon monoxide has been reported to show relatively improved cycling performance compared to Si-containing materials for rechargeable lithium batteries, due to the structural buffering role of in-situ formed $Li_2O$ and lithium silicate during the reaction of silicon monoxide and lithium. Here we report improved cycling ability of interfacially stabilized Si-$SiO_2$-graphite composite anode using silane-based electrolyte additive for rechargeable lithium batteries, which includes low cost silicon dioxide for structural stabilization and graphite for enhanced conductivity.