• KOREAN JOURNAL OF CROP SCIENCE
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• v.52 no.1
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• pp.69-80
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• 2007

Among the photoactive semiconductors such as $TiO_2,\;ZnO,\;Fe_2O_3,\;WO_3,\;and\;CdSe,\;TiO_2$ is the most widely used as photocatalyst in different media, because of its lack of toxicity and stability. In this study, the effects of titanium dioxide were investigated to obtain the information of physiological change in rice plant. Light-adapted Chlorophyll flourescence index decreased and relative electron transport rate of rice leaves was activated by titanium dioxide under $2,400\;{\mu}mol\;m^{-2}\;s^{-1}$ PAR (Photosynthetic active radiation). Relative electron transport rate of rice leaf treated with titanium dioxide 10 ppm was high in order of $2,400\;{\mu}mol\;m^{-2}\;s^{-1}\;PAR,\;2,200\;{\mu}mol\;m^{-2}\;s^{-1}\;PAR,\;450\;{\mu}mol\;m^{-2}\;s^{-1}\;PAR$ and titanium dioxide 10 ppm (45.1%), control (32.4%), diuron 10 ppm (15.3%) under $2,400\;{\mu}mol\;m^{-2}\;s^{-1}\;PAR$. Titanium dioxide increased photosynthesis of the rice leaf under $13.6\;KJ\;m^{-2}\;day^{-1}$ UV-B only. With titanium dioxide 20 ppm, reduced UV-B ($0.15\;KJ\;m^{-2}\;day^{-1}$) intensity changed the induction of proteins and twenty-five proteins were identified. Among them, seventy proteins were up-regulated, four proteins were down-regulated and four proteins were newly synthesized. Function of these proteins was related to photosynthesis (52%), carbohydrate metabolism (4%), stress/defense (8%), secondary metabolism (4%), energy/electron transport (4%), and miscellaneous (28%).

• Korean Journal of Materials Research
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• v.5 no.4
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• pp.405-411
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• 1995

급냉응고된 Al-3.51wt%Li-0.34wt%Zr 합금의 시효거동을 시차주사열량계(DSC)에 의한 열분석 방법으로 조사하였다. DSC에 의한 비열측정 결과 $\delta$’의 석출에 의한 발열반응과 $\delta$, $\beta$ 및 복합석출상의 석출에 의한 발열반응을 확인하였으며 $\delta$’ 및 $\delta$의 재고용에 의한 2개의 흡열반응을 확인하였다. 7$0^{\circ}C$ 저온시효시 $\delta$’의 석출에 의한 발열반응 이전에 흡열반응이 나타났으며 이것은 $\delta$’ 석출 이전에 $\delta$’ 전구생성물이 형성되었음을 의미한다. DSC 곡선상에 나타난 발열과 흡열곡선을 해석하여 얻은 $\delta$’상 석출과 재고용의 활성화에너지값은 각각 83KJ/mol과 98KJ/mol로서 Al-Li 2원계 및 Al-Li-Mg에 비해 높은 값을 나타내엇으며, 시효에 의한 강화가 일어나 DSC에 의한 비열변화 조사결과 나타난 $\delta$’상 석출 완료 시효조건점 (21$0^{\circ}C$, 1시간)에서 최고경도값(Hv 160)을 나타내었다.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 1986.12a
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• pp.523.1-523
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• 1986

To extend the spectrum of enzyme utilization in the organic solvent system, C. rugosal lipase was selected as a model enzyme because its substrate is soluble to organic solvent. One of the serious disadvantages in this system was the deactivation of the lipase. The pattern of lipase deactivation was the biphasic model. The activation energies for the deactivation were 14.05${\times}$10$^4$ KJ/Kg mole in the first phase and 3.59 ${\times}$ 10$^4$ KJ/mole in the second phase. The several factors were studied for their influences on the pattern of deactivation. Iso-octane as organic solvent influenced more on the first phase than the second phase. Urea as the reagent affecting boty hydrophobic interaction and hydrogen bond of enzyme also influencea more on the first phase. And the optimum pH for the activity was not correlated to that of the stability.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.37 no.10
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• pp.683-693
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• 1988

For the economical and reasonable operation of electric power system according to continual increase of electric power demand and decrease of load factor, the potential application of superconducting magnertic energy storage [SMES] with high efficiency and fast response in the electric utility is receiving attractive attension. In the light of this background, to confirm the basic principle of SMES, theoretical study, design technique and fabrication procedure for superconducting coil, current lead, cryostat, measuring and protection system of SMES are described in detail. Especially, a new design technique for superconducting coil and current lead is porposed and it was proved experimentally by the performance test of SMES which is developed for the first time in our country. At the peak operating current 200A, the maximum magnetic field amd stored energy of the coil are 3.52T and 2500J, espectively. The thermal and mechanical stability of 2500J SMES is also confirmed experimetally by its characteristics test, AC loss, protection system, charge and discharge test. The experimetal results show good characteristics of energy storage system.

• Journal of Fisheries and Marine Sciences Education
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• v.22 no.2
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• pp.195-204
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• 2010

As the throughout of transshipment oil cargo in Korea has been increasing, the importance and competition of the oil hub port has also been increasing. The aim of this study is to suggest how the factors influence the competitiveness of the oil hub port based on the specialists' opinions. For doing this, the evaluating factors were obtained from both previous studies and brainstorming of the professionals from the oil hub port. These were divided into groups by the ‘KJ method' according to 5 criteria and were made into a 3 level hierarchy structure. The ‘AHP method' identified the relative importance of factors and trends from the preferences of the specialists. This study presents the factors influencing the competitiveness of the oil hub port.

• Proceedings of the Zoological Society Korea Conference
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• 2000.10a
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• pp.228.3-229
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• 2000

No Abstract, See Full Text

• Nuclear Engineering and Technology
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• v.21 no.2
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• pp.89-98
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• 1989

The expanding copper mandrel test performed at three strain rates (3.2$\times$10E -5/s, 2.0$\times$10E-6/s and 1.2$\times$10E-7/s) over 553-873 K temperature range by varying the heating rates (8-1$0^{\circ}C$/s, 1-2$^{\circ}C$/s and 0.5$^{\circ}C$/s) in air and in vacuum (5$\times$10E-5 torr). The yield stress peak, the strain rate sensitivity minimum and the activation volume peaks could be explained in terms of the dynamic strain aging. The activation energy for dynamic strain aging obtained from the yield stress peak temperature and strain rate was 196 KJ/mol and this value was in good agreement with the activation energy for oxygen diffusion in $\alpha$-zirconium and Zircaloy-2 (207-220 KJ/mol). Therefore, oxygen atoms are responsible for the dynamic strain aging which appeared between 573 K and 673 K. The yield stress increase due to the oxidation was obtained by comparing the yield stress in air with that in vacuum and represented by the percentage increase of yield stress ( $\sigma$$^{a}$ $_{y}$ - $\sigma$$^{v}$ $_{y}$ / $\sigma$$^{v}$ $_{y}$ ). The slower the strain rate, the greater the percentage increase occurs. In order to estimate the yield stress of PWR fuel cladding material under the service environment, the yield stress in water was obtained by comparing the oxidation rate in air that in water assuming the relationship between the oxygen pick-up amount and the yield stress increase.

• Journal of Microbiology and Biotechnology
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• v.12 no.5
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• pp.722-728
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• 2002

Eight strains producing bacterial cellulose (BC) were isolated from rotten fruits and traditionally fermented vinegars. One of the isolated strains from the rotten grape in Gwangju, Korea, maintained a relatively stable BC production in shaking cultures. This isolated strain proved to be Acetobacter xylinum, based on several biochemical and morphological tests. It was shown that the slant-baffled flask was more efficient than the conventional flask for the BC production in shaking cultures. To determine the most suitable carbon and nitrogen sources for the production of BC, various compounds were examined. Fructose was found to be the most effective carbon source with an optimal concentration of 2%. Mixed carbon source (glucose:fructose=1:3) was also better than glucose or fructose alone. Optimal nitrogen source, when basal medium was used, was 10% (v/v) com steep liquor (CSL). When com steep liquor was used with a mixed carbon source (glucose:fructose=1 :3),4% CSL exhibited the best BC production. Based on these results, a defined medium was developed for the BC production by Acetobacter xylinum KJ-1. When this medium was used under optimal culture conditions, the BC production was 7.2 g/1, which was approximately 3 times higher than that with the traditional HS medium.

• Korean Journal of Food Science and Technology
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• v.30 no.3
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• pp.655-659
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• 1998

Bacterial strain showing the strong fibrinolytic activity (2.04 plasmin unit) was screened from Jeot-Gal, Korean salt-fermented fish collected from various region. For the identification, when the strain was characterized morphologically, culturally, and biochemically, it was identified to Bacillus pumilus. And, when the fatty acids composition of the strain was analyzed, it was identified to Bacillus atropheus. Finally, the 16S rRNA partial sequence (V3 region) showed that the fibrinolytic stain screened from Jeot-Gal was identified as Bacillus subtilis. So, we named it Bacillus subtilis KJ-48.

• Journal of Life Science
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• v.19 no.3
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• pp.343-348
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• 2009

Magnaporthe oryzae, a major cause of rice blast, is one of the most destructive plant fungal pathogens. Secretion of reactive oxygen species (ROS) during the infection phase of plant pathogenic fungus plays a key role in the defense mechanism of a plant. ROS causes oxidative damage and functional modification to the proteins in a pathogenic fungus. Methionine, especially, is a major target of ROS, which oxidizes it to methionine sulfoxide. To survive from the attack of ROS, plant pathogenic fungus has antioxidative systems - one example would be methionine sulfoxide reductase B (MSRB), which reverses the oxidative alteration of methionine to methionine sulfoxide. In the present study, identification and molecular characterization of the MSRB gene in M. oryzae KJ201 were investigated. The MSRB gene was amplified by PCR from the M. oryzae KJ201 genomic DNA. The copy number of MSRB in the genome of M. oryzae KJ201 was identified by Southern blot analysis, which revealed that the gene exists as a single copy. To study the molecular function of an MSRB gene, the expression level of the MSRB gene was assayed with hydrogen peroxide treatment by Northern blot analysis and RT-PCR. The expression of the MSRB gene was increased by treatment of hydrogen peroxide, without significant correlation to hydrogen peroxide concentrations. These results indicate that the MSRB gene in M. oryzae KJ201 could contribute to protection against plant defense compounds such as ROS and offer a novel strategy for the control of rice blast.