• Korean Journal of Organic Agriculture
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• v.11 no.4
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• pp.103-115
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• 2003

In order to investigate the possibility for use to control environmental pollution, Kenaf(Hibiscus cannabinus L.) was used to obtain information of their growth and $CO_2$ response under different temperatures and $CO_2$ concentration. The highest percentage of germination and aboveground dry mass of Kenaf were found at 30$^{\circ}C$ and 35$^{\circ}C$ by 89.0% and 3.2g, respectively under different temperatures. The amount of $CO_2$ absorption and aboveground dry mass production of Kenaf were higher than those of maize during the whole growing period and the last sampling of aboveground dry mass of Kenaf and maize were 252.9g and 200.8g, respectively. The highest plant height was found at 400ppm by 131.0cm and the next was in the order of 600ppm by 1293cm, and 800ppm by 108.8cm. Leaf area was higher in the order of 400ppm > 600ppm > 800ppm, whereas leaf dry mass was in the order of 800ppm > 600ppm > 400ppm under different $CO_2$ concentration, showing that leaf became thicker as $CO_2$ concentration was increased. Days from seeding to flowering became shorter by 13 days in 35/25$^{\circ}C$ compared with 25/15$^{\circ}C$ between two temperature regimes and they also became shorter as $CO_2$ concentration was increased. Aboveground dry mass was higher in 35/25$^{\circ}C$ than that of 25/15$^{\circ}C$ between two temperature regimes. while it was increased in the order of 800ppm > 600ppm > 400ppm as CO2 concentration was increased. Temporal changes of leaf dry mass during growth period showed no difference between $CO_2$ concentration in 25/15$^{\circ}C$ , but the highest of it was found at 800ppm in 35/25$^{\circ}C$. The highest temporaI increase of root dry mass was found at 800ppm in 25/15$^{\circ}C$, but 35/25$^{\circ}C$ showed no difference between different $CO_2$ concentration.

• Tribology and Lubricants
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• v.16 no.1
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• pp.33-38
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• 2000

Abstract- In this paper tribological characteristics of solid and liquid phase sintered W/C-35%Ni tappets were investigated. Three test methods were performed to investigate the wear and surface damage mechanism of sintered tappets. First, block-on-ring wear test was performed to investigate the wear characteristics under pure sliding condition. Second, simplified cam and tappet tests (called component wear test hereafter) were carried out to simulate the real contact history of cam and tappet. Also, after the test, contact surfaces were analyzed with scanning electron microscope to study the wear mechanism. As a final screening, engine dynamo tests were performed. Results showed that in the block on ring sliding wear test, solid phase sintered specimens showed superior wear resistance to liquid phase sintered specimens. The component wear tests and engine dynamo tests also showed the same results. Therefore, in these tests, solid phase sintered tappet material revealed superior wear resistant properties to liquid phase sintered one.

• Transactions of Materials Processing
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• v.7 no.4
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• pp.400-406
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• 1998

The press formability analysis of welding parts was studied in the current work by the tailor welded blank. The press formability was tested by means of the flash weldability and the formability for two kinds of materials (SPCC & S35C). The results indicate that SPCC & S35C steel sheets showed good weldability and formability after an optimum welding conditions. The independent operation variables were characterized by strength of welding parts, deformation after the welding, press formability of welding parts and productibility of welding. The weldability and the quality of welding parts of the flashed SPCC steel sheet was superior to those of the S35C steel sheet, since a higher carbon content in steel sheet led to a higher hardness. The experimental results were discussed by the evaluation of the results obtained from tensile test, hardness test, micro-structure and V bending test.

• Korean Journal of Food Science and Technology
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• v.17 no.2
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• pp.60-64
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• 1985

To utilize microbial lipases for hydrolysis of milk fat, optimum reaction conditions and characteristics of enzymatic reactions of lipases originated from Rhizopus delemar, Mucor sp., and Candida cylindracea were investigated. Optimum pH and temperature were pH 5.6 and $45^{\circ}C$ for Rhizopus delemar lipase, pH7.5 and $35^{\circ}C$ for Mucor sp. lipase, and pH7.5 and $35^{\circ}C$ for Candida cylindracea lipase. Optimum lipase concentration and optimum substrate concentration were $600{\sim}800\;units/ml$ and 20% milk fat, regardless of their origin. Km values were 6.06% milk fat for Rhizopus delemar lipase, 7.69% for Mucor sp. lipase and 7.99% for Candida cylindracea lipase. Rate of lipid hydrolysis was Rhizopus delemar lipase>Mucor sp. lipase>Candida cylindracea lipase. As the reaction time was extended, liberation of short chain fatty acids was increased. After 8 hours reaction, capric acid content significantly increased with Candida cylindracea lipase, palmitic acid with Mucor sp. lipase and butyric acid with Rhizopus delemar lipase.

• Applied Biological Chemistry
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• v.25 no.3
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• pp.119-125
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• 1982

Using piston type extruder, barley flour was extruded at various processing conditions, The used variables were three shear rates (apparent shear rate 118, 534, $1169sec^{-1}$), four extrusion temperatures(90, 120, 150, $180^{\circ}C$) and three moisture contents (15, 25, 35%). The rheological properties and the extrudate quality were monitored in extrusion. Barley flour showed pseudoplastic behavior having average power law index 0.28 in used shear rate range. When viewed from general appearance, die swell, density, water uptake, rehydration swell and gelatinization degree of extrudate, $25{\sim}35%$ moisture and $120^{\circ}C$ temperature was suitable processing condition for noodle-like product, and 25% moisture and $150^{\circ}C$ temperature was good for snack or flake product. Moisture content of the extrudate can be pretty well estimated from energy balance at higher temperature and higher moisture content.

• KSBB Journal
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• v.14 no.4
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• pp.490-494
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• 1999

This study was carried out to examine some factors affecting the supercritical carbon dioxide extraction of genistein from soybean. The factors investigated in this study were pressure, temperature, flow rate of carbon dioxide, and concentration of modifier. It was foumd out that genistein is not extracted in the absence of modifier. Ethanol was found to be more effective modifier than methanol. 70% of genistein was extracted at 35$^{\circ}C$, 300bar and ethanol 15% (w/v) as compared with the performances of organic solvent extraction.

• Journal of Fisheries and Marine Sciences Education
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• v.24 no.6
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• pp.755-762
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• 2012

Qualities properties of fish sauce made jack mackerel (Trachurns japonicus) at different salt concentrations (25~35%) for 240 days at fermentation temperature ($25{\sim}55^{\circ}C$) were investigated. Total nitrogen content of the fish sauce made jack mackerel at 25% salt concentration after 240 day of fermentation was higher than those of 30%, 35% salt concentration. Total nitrogen content was increased under the same condition as fermentation temperature increased except at $55^{\circ}C$. Amino nitrogen contents at 25% salt concentration after 240 day of fermentation at 35, 45, $55^{\circ}C$ were 949.3, 812.8 and 834.4 mg/100 g, respectively. Those at 25, $55^{\circ}C$ fermentation temperature were 811.2 and 614.8 mg/100 g, respectively. The amino acid nitrogen content at 30 and 35% salt concentration ware lower than 20% salt concentration and that after 240 day of fermentation at $55^{\circ}C$ was lowest. The volatile basic nitrogen content increased during fermentation as fermentation temperature increased. However, increasing salt concentration controlled the formation of volatile basic nitrogen. Histamine content of samples fermented at $25{\sim}55^{\circ}C$ after 240 days were 9~20 mg/kg showing that it was not significantly different among salt concentration. The results indicated that the controlled salt concentration and fermentation temperature could be used as a successful process for fish sauce of jack mackerel as an unused resource.

• The Korean Journal of Zoology
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• v.38 no.4
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• pp.449-456
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• 1995

Seasonal changes in the activity and charaderistics of brain Na+, K+-ATPase and Mg2+-AWase were investigated in frog (Rana dybowskii) The brain Na+, K+-ATPase adivity during hibernation was similar to that in active period in frogs. The Na+, K+-AWase activity increased in December and March, when the frogs enter into and awake from the hibernation. Over 5-35$^{\circ}C$ temperature range, Na+, K+-ATPase showed non4inear Arrhenius kinetics throughout the year. The brain Mg2+-ATPase activity decreased during hibernation, but markedly increased in March. The Arrhenius plots for Mg2+-AWase activity were linear in frogs both in torpid and active state. The ratio of Na+, K+-AWase activity at 15~C to at 35~C did not change during hibernation. The sensitivity of Na+, K+-AWase to ouabain was also unchanged throughout the year. These results indicate that the activity and charaderistics of brain Na+, K+-AWase remain unchanged during hobernadon in frog.

• Journal of Life Science
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• v.13 no.3
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• pp.308-313
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• 2003

The collagenase gene from Vibrio parahaemolyticus 04 was subcloned into an expression vector pET-29b. The recombinant collagenase was expressed in Escherichia coli BL2l(DE3) and partially purified by Hi-Trap affinity and Sephacryl S-100 size exclusion chromatographies. The recombinant enzyme was purified by 43.7-fold and the yield was 73%. SDS-PAGE revealed that the molecular weight of the enzyme was approximately 35 kDa. Substrate specificity study of the enzyme displayed that the enzyme showed the highest activity with the type I collagen and the synthetic peptide, Z-GPGGPA, indicating that the enzyme was indeed a collagenase. The enzyme showed broad pH optimum around pH 6-12 and was stable between pH 5.5 and 11.5. The optimum temperature for the type I collagen degradation was $35^{\circ}C$. The thermostability measurement of the enzyme indicated that the enzyme was stable up to $55^{\circ}C$, but the activity was diminished quickly above $60^{\circ}C.$

• Korean Journal of Materials Research
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• v.22 no.7
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• pp.342-345
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• 2012

The dielectric properties and phase transformation of poled <001>-oriented $Pb(Mg_{1/3}Nb_{2/3})O_3-x%PbTiO_3$(PMN-x%PT) single crystals with compositions of x = 20, 30, and 35 mole% are investigated for orientations both parallel and perpendicular to the [001] poling direction. An electric-field-induced monoclinic phase was observed for the initial poled PMN-30PT and PMN-35PT samples by means of high-resolution synchrotron x-ray diffraction. The monoclinic phase appears from $-25^{\circ}C$ to $100^{\circ}C$ and from $-25^{\circ}C$ to $80^{\circ}C$ for the PMN-30PT and PMN-35PT samples, respectively. The dielectric constant (${\varepsilon}$)-temperature (T) characteristics above the Curie temperature were found to be described by the equation$(1/{\varepsilon}-1/{\varepsilon}_m)^{1/n}=(T-T_m)/C$, where ${\varepsilon}_m$ is the maximum dielectric constant and $T_m$ is the temperature giving ${\varepsilon}_m$, and n and C are constants that change with the composition. The value of n was found to be 1.82 and 1.38 for 20PT and 35PT, respectively. The results of mesh scans and the temperature-dependence of the dielectric constant demonstrate that the initial monoclinic phase changes to a single domain tetragonal phase and a to paraelectric cubic phase. In the ferroelectric tetragonal phase with a single domain state, the dielectric constant measured perpendicular to the poling direction was dramatically higher than that measured in the parallel direction. A large dielectric constant implies easier polarization rotation away from the polar axis. This enhancement is believed to be related to dielectric softening close to the morphotropic phase boundary.