• Microbiology and Biotechnology Letters
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• v.24 no.2
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• pp.143-148
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• 1996

Thousand actinomycetes and 50 soil samples were used for the isolation of microorganisms producing yeast cell wall lytic enzymes. Among 493 strains producing large clear zones on autolysed washed yeast (AWY), 117 strains were selected on living yeast cell agar plates. With the method of lytic activity, one strain (St-1702) was selected, which was temporarily identified as Streptomyces eurythermus. The optimal condition for enzyme production of this strain was partially determined as follows: incubation of the strain for 3 days at 30$\circ$C in the medium containing 2% freeze dried yeast cell, 1% glucose, 1% K$_{2}$HPO$_{4}$, 0.01% MgSO$_{4}$'7H$_{2}$O, 0.5% peptone, and 0.2% (NH$_{4}$)$_{2}$CO$_{3}$ with pH 7.0. The protoplast formation of yeast by using the enzyme produced by this strain was compared with commercial enzymes.

• Microbiology and Biotechnology Letters
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• v.24 no.2
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• pp.206-212
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• 1996

The strain producing bioemulsifier was isolated from soil samples. The isolated strain was identified as the genus Acinetobacter through its morphological, cultural and physiological characteristics. The highest emulsification activity and stability by Acinetobacter sp. BE-254 was observed after 5 days of cultivation in the culture medium containing n-hexadecane 4%, NaNO$_{3}$ 0.2%, KH$_{2}$PO$_{4}$ 0.01%, MgSO$_{4}$-7H$_{2}$O 0.01%, CaCl$_{2}$ 0.01%, and yeast extract 0.01%. The optimum pH and temperature for bioemulsifier production were pH 7.0 and 30$\circ$C, respectively. Furthermore the most of bioemulsifier was produced during the exponential growth phase, and this suggested that the bioemulsifier production was growth-associated. The bioemulsifier showed good emulsification activity on various emulsifying substrates such as hydrocarbons, edible oils, and petroleum fractions.

• 한국정보디스플레이학회:학술대회논문집
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• 2000.01a
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• pp.23-24
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• 2000

A new PDP cell structure called CSP (Charge Storage Pad) improves the luminous efficiency by 1.6 times and prevents cross talk between adjacent cells. The CSP, which is a conducting material, is inserted between the dielectric layer and the MgO film in the front plate. This CSP produces a longer time-averaged discharge path to get a high luminous efficiency and confines the discharge to prevent cross talk.

• Journal of Korea Foundry Society
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• v.24 no.5
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• pp.290-294
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• 2004

The effect of carbon equivalent on the fading behavior of hypoeutectic ductile cast iron was investigated. The carbon content was slightly increased right after graphite spheroidization treatment and remained almost constant with holding at $1,490^{\circ}C$ after 4 minute. The residual magnesium content was decreased slowly with holding. The empirical equation expressing the relationship between this and holding time was proposed ; $C=C_o-P{\times}t$. The proportionality constant, P, was inversely proportional to carbon content.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.24-27
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• 2009

A hybrid model has been developed which adopts a fluid model for electrons and a particle-in-cell (PIC) model for ions. Using the hybrid simulation, the discharge characteristics are investigated with the diagnostics for the electric field and the wall charge profile, density distributions of charged and excited particles, distributions of ultraviolet lights on phosphor, and the visible lights emitted from the PDP cell. Also, energy and angle distributions of the ions at the MgO protective layer are obtained for the analysis of material effect. The comparison of hybrid simulation results with experimental results as well as that with the conventional fluid simulation shows that the new model is more adequate for the simulation of PDP cells.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.16 no.1
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• pp.20-24
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• 2006

Iridium-catalyzed carbon nanofilaments were formed on MgO substrate as a function of the gap between the substrate and the plasma using microwave plasma-enhanced chemical vapor deposition method. Under the remote plasma condition, carbon nanofibers were formed on the substrate. Under the adjacent plasma condition, on the other hand, carbon nanotubes-like materials instead of carbon nanofibers could be formed. When the substrate immersed into the plasma, any carbon nanofilaments formation couldn't be observed. During the reaction, the substrate temperatures were measured as a function of the gap. Based on these results, the cause for the different carbon nanofilaments formation according to the gap was discussed.

• Microbiology and Biotechnology Letters
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• v.24 no.5
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• pp.591-596
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• 1996

In the course of screening lipid peroxidation inhibitor from basidiomycetes, a mushroom, which was collected at O-Dae mountain in Kangweon- Do, was found to have active compound. The mushroom was identified as Polyzellus multiplex, which belongs to Aphylloporalles Thelephoraceae, on the basis of macroscopic and microscopic characteristics of the fruiting body. The methanol extract of fruiting body was extracted with benzene and ethylacetate, sequentially. By using various kinds of chromatographies, PM1, and PM2 and PM3, were purified from the ethylacetate extract and the benzene extract, respectively. Color reaction and analyses of IR, UV, and NMR spectra indicated that PM1 was a derivative of thelephoric acid, and PM2 and PM3 were linoleic acid and oleic acid, respectively. IC$_{50}$ of PM1 for inhibition of lipid peroxidation was 1.96 ppm and LD$_{50}$ was 500 mg/kg.

• Journal of Ginseng Research
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• v.24 no.3
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• pp.143-147
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• 2000

In previous studies we have demonstrated that several individual ginsenosides such as Rc, Rd, Re and Ri relieves formalin-induced pain following systemic treatment. But it is unknown where these single ginsenosides induce antinociception. We investigated the antinoiceptive effect of four individual ginsenosides on formalin-induced pain after intrathecal (i.t.), intracereventricular (i.c.v.), or subcutaneous (s.c.) administration using mice. We found that ginsenoside Rc, Rd, and Re except Rf attenuated both acute and tonic phase of pain. Ginsenoside Rf attenuated only tonic phase of pain after i.t. administration. The ED$\_$50/ was 1.0 (0.55∼l.75 mg/kg) for Rc, 1.15 (0.6∼2.25 mg/kg) for Rd, and 8.9 (3.9∼20.5 mg/kg) for Re in acute phase of pain. The ED$\_$50/ was 0.3 (0.1∼0.85 mg/kg) for Rc, 0.6 (0.35∼l.1 mg/kg) for Rd, 2.45 (1.25∼4.65 mg/kg) for Re, and 1.9 (1.5∼4.25 mg/kg) for Rf in tonic phase of pain. We also found that ginsenoside Rc, Rd, Re, and Rf after i.c.v. administration attenuated both acute and tonic phase of pain. The ED5o for acute phase of pain was 0.9 (0.55∼l.4mg/kg) for Rc, 0.9 (0.45∼1.7 mg/kg) for Rd, 0.93 (0.5∼l .75 mg/kg) for Re, and 1.85 (0.95∼3.5 mg/kg) for Rf. The ED$\_$50/ for tonic phase of pain was 0.7 (0.45∼1.05 mg/kg) for Rc,1.25 (0.7∼2.2 mg/kg) for Rd, 0.85 (0.45∼1.6 mg/kg) for Re, and 0.8 (0.4∼1.45 mg/kg) for Rf. Thus, the order of the analgesic potency was Rc$\geq$Rd>Re>Rf in both i.t. and i.c.v. administration routes. However, s.c. pretreatment of four ginsenosides did not reduce formalin-induced pain. These results suggest that analgesic effect of ginsenosides is achieved through spinal or supraspinal site(s) in formalin test.

• Korean Journal of Environmental Agriculture
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• v.38 no.4
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• pp.273-280
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• 2019

BACKGROUND: The reclaimed lands for agricultural use managed by the Korean government is consisted of 17,145 hectares of lands under construction and 13,384 hectares of completed lands. In order to utilize these reclaimed lands as competitive agricultural complexes, the government is preparing to develop comprehensive development plans for multiple purposes. For rational land-use planning and soil management, information of the soil chemical properties is necessary. METHODS AND RESULTS: From 2013 to 2016, soil samples were collected from 85 representative sampling sites of the reclaimed lands and analyzed for soil chemical properties including electric conductivity (EC), pH, soil organic matter (SOM), and nutrients. The annual mean soil EC ranged from 5.1 to 8.3 dS m^-1 and have continued to decrease over the years (estimation equation with EC as dependent and year as independent variable was y =0.0736x² - 1.4985x + 9.8305, R² = 0.9753). The pH ranged from 7.3 to 7.6, which was higher than the optimum range (5.5~7.0) for agricultural soils. Soil organic matter (8 to 11 g kg^-1) was lower level than the optimum range (20~30 kg^-1). Available silicate (Av.SiO₂) ranged from 169 to 229 mg kg^-1, which was close to the minimum content (≥157 mg kg^-1) for rice paddy field. Available phosphate (Av.P₂O₅) content (24~39 mg kg^-1) was lower than the optimum range (80~120 mg kg^-1) for rice paddy field. CONCLUSION: For efficient agricultural use of reclaimed lands under government management, our results suggest that the application of organic matter and supplying deficient nutrients as well as desalinization is required.

• Journal of the Korean Applied Science and Technology
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• v.11 no.1
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• pp.7-16
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• 1994

Some seeds of the Rutaceae family, Zanthoxylum piperitum, Z. schinifolium officinalis, Poncirus trifoliata, Citrus unshin, were investigated to clarify their antioxidative components. Finely powdered samples were extracted by hexane, followed by dichioromethane and then 70% methanol in a hot bath. Its unsaponifiables containing X-and Y-tocopherol with trace amount of ${\beta}-and$\;{\delta}-tocopherol$. also showed comparatively weak activity, although the hexane fraction itself had no significant antioxidative effect on lard. Levels of total tocopherols in the samples averages 42. 24-154. 11 mg/lOOg total extractives. The dichloromethane-and 70% methanol extractives showed strong antioxidative activity, from which antioxidative substances were purified with benzene-acetone(6:5, V/V) on a silica gel column, and with a solvent mixture of acetonitrile-methanol-$H_2O$(40:40:20, V/V/V) on a Sep-Pak $C_{18}$ hydrolyzed by 5% KOH-ethanol. The recovered unsaponifiables were, then, separated on a column of high performance liquid chromatography. The unsaponifiables produced by hydrolysis of the isolates from dichloromethane extractives has epi-catechin(40.0-57.1%) and (+)-catechin<$l9.1{\sim}24.4%$ to total phenolic substances, on area base) as major component, accompanied by chlorogenic acid, gallic acid(?), trans-p-coumaric acid and tralls-p-ferulic acid including some unknown components, and those derived from 70% methanol extractives also comprise (+)-catechin($31.3{\sim}39.6%$ to total components, on area base), epi-catechin($2O.2{\sim}36.4%$), trans-p-cournaric acid(8.4-15.3%) and trans-p-ferulic acid($7.7{\sim}14.1%$) as predominant component with some minor coponents, but the fraction supposed to be gallic acid(?) is not present. The antioxidative activities of the phenolic components isolated in this work were in order of epi-catechin>catechin>chlorogenic acid>trans-p-ferluic acid>trans-p-coumaric acid.