• KSBB Journal
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• v.7 no.3
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• pp.186-190
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• 1992

The compositions of amino acid in the protein and total fatty acid of Dendrolimus spectabilis were analyzed quantitatively by HPLC and GC, respectively. The contents of crude oil and protein from the extracts were 21.00% and 58.47%, respectively. The amount of free amino acids in the protein was 3.65g/100g, and 1.31g/100g of essential amino acids was contained in the free amino acids. The amount of total amino acids in the protein was 41.20g/100g, and 14.75g/100g of essential amino acids were contained in the total amino acid. The compositions of fatty acid in the oil were $C_{18}$=26.81%, $C_{16}$=19.09%, $C_{18:1}$=18.74%, $C_{18:3}$=15.33%, $C_{16:1}$=7.29%, $C_{20}$=5.21% in order, respectively. 45.88% of unsaturated fatty acids were contained in the oil.

• Journal of Ocean Engineering and Technology
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• v.2 no.2
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• pp.112-121
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• 1988

A study on friction welding of carbon steel bar (SM45C) to chrome molybedenum steel bar(SCM4) is examined experimentally through tensile test, hardness test, microstructure test and fatigue test. so, this paper deals with optimizing the welding concitions and analyzing various mechanical properties about friction welds of SM45C to SCM4 steel bars. The results obtained are summarized as follows; 1) For friction welded joints of SM45C to SCM4 steel bars, the total upset(U)increases linearly with an increase of heating time ($t_{1}$) till 6s. 2) The determined optimum welding conditions are heating time ($t_{1}$)2s, upsetting time($t_{2}$), 3s, heating pressure($p_{1}$), 4kgf/$mm^{2}$(39.2MPa), upsetting pressure($p_{2}$, 8kgf/mm$^{2}$(78.4MPa) and rotating speed(N), 2, 000rpm when the total upset(U) is 3.4mm, resulting in a computed relationship between the joint tensile strength .sigma.$_{t}$ (kgf/mm$^{2}$and the total upset U(mm); .sigma.$_{t}$ =$0.21U^{3}$ - $3.38U^{2}$ +17.03U + 66.00 3) As the elongation is increased more and more, the fracture position becomes away from weld interface and the fractures are similar to those of SM45C. Fracture is taken place on SM45C side. 4) The weld interface of two dissimilar materials is mixed strongly, and the heat affected zone is about 2.0mm at SM45C while about 2.7 mm at SCM4 side. Therefore, the welded zone and heat affected zone are very narrow, comparing with those of the joints welded by the other welding methods. 5) The fatigue strengths at N=10$^{6}$ cycles of SM45C, SCM4 and friction welded joints are 23kgf/$mm^{2}$, 33kgf/$mm^{2}$(220.5 MPa), and 22.5kgf/$mm^{2}$(220.5MPa) respectively, and fracture at friction welded joint takes place at the side of SM45C. 6) The hardness of the friction weld interface is 3 times higher than that of base metal. 7) Fatigue strength of friction welded joint is higher than that of base metal. 8) Notch sensitivity factor of friction welded joint is lower than that of base metal.

• Mycobiology
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• v.33 no.4
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• pp.200-205
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• 2005

In Northern Bangladesh, generally mango trees are planted as agroforest that gives higher Net Present Value (NPV) than traditional agriculture. Mango anthracnose caused by Colletotrichum gloeosporioides Penz. is seen as a very destructive and widely distributed disease, which results in poor market value. Five fungicides such as Cupravit, Bavistin, Dithane M-45, Thiovit and Redomil were tested against conidial germination of C. gloeosporioides. Dithane M-45 and Redomil were the most effective when the conidia were immersed for $10{\sim}20$ minutes at $500{\sim}1000\;ppm$ concentrations. Antifungal activities of 13 plant extracts were tested against conidial germination of C. gloeosporioides. Conidial germination of C. gloeosporioides was completely inhibited in Curcuma longa (leaf and rhizome), Tagetes erecta (leat) and Zingiber officinales (rhizome) after 15 minutes of incubation respectively.

• Korean Journal of Materials Research
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• v.3 no.6
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• pp.598-605
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• 1993

Methacryloxyethyl dimethyl alkyl($C_{1}\sim C_{12}$, benzyl and 2, 2-diethoxy ethyl) ammonium bromide monomers were prepared to investigate the relative humidity characteristics for polymer electrolytes with different chemical structures. They were coated on the alumna substrate printed comblike gold electrode by photopolymerization after micro-syringe injection. As the thickness of rhe humid membrane increased, the impendance decreased, whereas the impedance ~ncreased as the carbon cham of alkyl substituent in the monomer increased. The impendance of the polymeric electrolytes with $C_6\sim C_8$ substituents were varied from 19M$\Omega$ to 5K$\Omega$ for the range of 30-90% Mi. The temperature depedence coefficient in the range of 15-$35^{\circ}C$ was found to be -0.45% $RH/^{\circ}C$and the hysteresis falled within the range of $\pm$2% RH. The response time was 35 second for varying humldity from 33% to 85% RH.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.45 no.4
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• pp.343-350
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• 2012

Even though the microalgal species of Isochrysis and Pavlova are widely used as live food in bivalve hatcheries, they are difficult to culture in mass during the summer season. Therefore, the present study was conducted to determine the optimum species or strains of Isochrysis and Pavlova to produce good growth and high contents of fatty acids at temperatures over $30^{\circ}C$. Four species of Isochrysis (I. galbana KMMCC12, I. galbana KMMCC214, I. aff. galbana, and Isochrysis sp.) and four of Pavlova (P. lutheri, P. gyrans, P. viridis, and Pavlova sp.) were cultured at $25^{\circ}C$, $29^{\circ}C$, and $33^{\circ}C$, and then analyzed for specific growth rate and fatty acid composition. Microalgae were cultured in f/2 medium at 23 psu and continuous light of $80{\mu}mol$ photons $m^{-2}s^{-1}$. For the I. galbana, growth rates were highest at $29^{\circ}C$ and decreased at $33^{\circ}C$ to the level observed at $25^{\circ}C$. I. galbana (KMMCC12) and Isochrysis sp. cultured at $29^{\circ}C$ and $33^{\circ}C$, respectively, exhibited the highest growth rates of all Isochrysis species. In terms of fatty acids, I. galbana (KMMCC12) contained higher contents of PUFA and n-3 HUFA at $33^{\circ}C$ than did Isochrysis sp. For species of Pavlova, growth rates of P. gyrans and P. viridis at $29^{\circ}C$ and $33^{\circ}C$, respectively, were higher than those of the other Pavlova species. In particular, P. viridis grew as well at $33^{\circ}C$ as it did at $29^{\circ}C$. However, P. lutheri and Pavlova sp. did not grow at $33^{\circ}C$. In terms of fatty acids, P. viridis cultured at $33^{\circ}C$ also exhibited higher contents of PUFA and n-3 HUFA, as compared to P. gyrans. Based on these results, we suggest that I. galbana (KMMCC12) and P. viridis are suitable species for mass culture during the high temperature season.

• Korean Journal Plant Pathology
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• v.13 no.3
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• pp.152-159
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• 1997

Six pathogenic Pythium isolates obtained from diseased ginger rhizomes were identified as Pythum myriotyrum Drechsler based on various morphological and physiological characteristics. The isolates showed strong virulence on underground parts of buds, crowns, rhizomes, roots and aerial parts of leaves and stems as well. The isolates caused rot of germinated seeds of 10 different crops tested, including cucumber and pepper, and markedly inhibited seedling growth of 3 crops tested, including corn and barley. Maximum, optimum and minimum growth temperatures for P. myriotylum were 39~45$^{\circ}C$, 33~37$^{\circ}C$ and 5~7$^{\circ}C$, respectively. Optimum pH for the growth was 6~7. Mycelial linear growth was most rapid on V-8 juice agar, but aerial mycelia were most abundant on PDA and corn meal agar. Zoosporangial and oogonial formation was greatest on V-8 juice agar. Optimum temperatures for the production of zoosporangia and oogonia were 20~35$^{\circ}C$ and 15$^{\circ}C$, respectively.

• Korean Journal of Food Science and Technology
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• v.15 no.2
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• pp.170-176
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• 1983

Starchy single cell protein produced by a starch-utilizing yeast, Sporobolomyces holsaticus FRI Y-5 was analyzed for its composition such as intracellular protein, amino acids, fatty acids, minerals, vitamins and pigments. It was shown that it contained 33.08% of total carbohydrate, 45.63% of crude protein, 20.01% of crude lipid, 3.24% of ash and 4.46% of pigment. Whole cell extracted by cold and hot NaOH method contained 40.89% of soluble protein and the estimated nucleic acid content from crude and soluble protein contents was about 7.6%. The sulphur-containing amino acids, threonine, isoleucine and valine were analyzed to be the limiting amino acids in the starchy SCP, and the protein score was calculated as 89.4. It was shown from its fatty acid analysis that it contained $6.5%\;of\;C_{16:0}$, $2.4%\;of\;C_{18:0}$, $81.9%\;of\;C_{18:1}$, $3.2%\;of\;C_{18:2}$, and $6.0%\;of\;C_{18:3}$. Also it was observed that it contained, per 100 g of dry cell, 365.33mg of Mg and 282.75mg of K more than Fe and Ca. The content of Vit. $B_2$ was 3.7mg per 100 g of dry cell, but niacin was not detected under this experimental condition. The UV-visible scanning result of pigment extract showed that the yeast contained carotenoid and unknown pigments.

• The Korean Journal of Food And Nutrition
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• v.16 no.4
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• pp.388-396
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• 2003

The freeze dried young antler residue was extracted by proteases and hydrochloric acid(HCl). The young antler was extracted by water at 50$^{\circ}C$ and the residue was reacted by proteases for 5 hours at 50$^{\circ}C$. The extraction rate of its residue was 32.8%(absorbance 3.61 at 280nm) of bacteria protease, 23.8%(absorbance 0.69) of papain, and 31.2% (absorbance 2.96) of pepsin. The young antler was extracted by boiling water and the residue was reacted by proteases for 5 hours at 50$^{\circ}C$. The extraction rate of its residue was 45.0%(absorbance 3.61) of bacteria protease, 30.4%(absorbance 0.33) of papain, and 51.2% (absorbance 2.77) of pepsin. The result of HPLC analysis reveals that in 50$^{\circ}C$ water extract and boiling water extract, all high molecular peak was reduced under MW 1,000 by proteases. The result from the extract of young antler residue reacted by HCl for 5 hours at 50$^{\circ}C$ shows that its extraction rate was 45% (absorbance 0.78) in concentration of 0.1N HCl, 61% (absorbance 1.82) in 0.2N, 81% (absorbance 2.29) in 0.4N, and 82.0% (absorbance 3.28) in 2.0N. The result of HPLC analysis also reveals that in the extract by 0.8N HCl, the peak of about MW 70,000 accounted for 78% in total. Protein content of the extract by 0.8N HCl was 8.2%, and content of amino acid was 81.6%, ash was 1.3%, and mineral contents were 0.1 % of Ca, 2.3% of P, 0.8 % of Mg, 3.4% of Na, 0.002% of F by dry base.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.6 no.2
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• pp.155-165
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• 1996

Growth of $LiNbO_3$ single crystal by Czochralski method was carried out to study the piezoelectric effects. Piezoelectric coefficients and elastic compliances of the $LiNbO_3$ single crystal were determined by the resonance method of length-extentional mode of bar resonator from the room temperature up to $100^{\circ}C$. Two dielectric constants of $LiNbO_3$ were also determined by measuring the capacitance of the plate specimen. Measured constants were piezoelectric coefficients $d_{15},d_{22},d_{31},d_{33}$ elastic compliances $s^E_{11},s^E_{33},2s^E_{13}+2s^E_{44},s^E_{14}$ and dielectric constants $K^T_{11},K^T_{33}$. As temperature increased, elastic compliances changed very slowly while piezoelectric coeffiecients and dielectric constant $K^T_{33}$ changed very rapidly. Electromechanical coupling constant of zyw ($45^{\circ}C$)-bar was as high as 0.51 in room temperature and nearly constant up to $1000^{\circ}C$. The increase of piezoelectric coefficients was mainly due to the increase of dielectric permittivity.

• Journal of the Korean Society for Marine Environment & Energy
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• v.10 no.1
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• pp.59-65
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• 2007

Rapid variation of coastal ecosystem in the East Sea of Korea, such as fishery resource variation and subtropical chang of bentic flora, accordong to the global warming are actually noticed. In this study we try to identify the characterics of water mass existing in this coastal area and to consider the variation of their physical and chemical properties using data of temperature, salinity and dissolved oxygen obtained by National Fisheries Research & Development Institute from 1960 to 2005. The temperature of all water mass rise during last 45 years; the rise of North Korea Cold Water temperature (about $2.33^{\circ}C$) is 1.5 times higher than that of Tsushima warm water (about $1.6^{\circ}C$), and the temperature rise of Tsushima Surface Water, directly affected by climate chang is $2.57^{\circ}C$, higher than the atmospheric temperature rise during same period, indicating that subtropical change makes progress more rapidly in the coastal marine ecosystem than in the land ecosystem. Otherwise, the salinity in the surface water decrease $0.29\%_{\circ}$ during last 45 years due to the rising trend of rainfall with atmospheric temperature. The dissolved oxygen concentration in the all water mass make a decreasing trend. Specially for the North Korea Cold Water, the dissolved oxygen concentration diminish 0.021 mg/l per year and the decrease in the East Sea Proper Water indicate a change of inner water circulation system.