• Journal of the Institute of Electronics Engineers of Korea SD
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• v.38 no.5
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• pp.1-1
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• 2001

비휘발성 메모리 소자로의 응용의 관점에서, sol-gel 방법으로 La 을 10mo1% 로 고정시킨 PLZT (10/y/z) 박막을 제작하여 Zr/Ti 조성비에 따른 구조적 및 전기적 특성을 조사하였다. PLZT(10/40/60) 박막은 로제트와 파이로클로르 상이 관찰되었으며, Zr/Ti 조성비에서 Ti 함유량이 증가함에 따라, (100) 배향성, 결정립 크기와 표면 거칠기는 증가되었다. 또한 Zr/Ti 조성비에서 Ti 함유량이 증가함에 따라, 10㎑ 에서 비유전율은 600 에서 400 으로 감소된 반면, 유전손실은 0.028 에서 0.053 로 증가되었으며, 170 ㎸/cm 에서 누설전류밀도는 1.64×$10^{-6}$ 에서 1.26×$10^{-7}$A/㎠ 으로 감소되었다. 그리고 ± 170㎸/㎝ 에서 측정한 PLZT 박막의 이력곡선을 측정한 결과, Zr/Ti 조성비가 40/60 에서 0/100 로 변화함에 따라 PLZT 박막의 잔류분극과 항전계는 6.62 에서 12.86 μC/cm2, 32.15 에서 56.45㎸/㎝ 로 각각 증가되었으며, 피로와 retention 특성 역시 개선되었다. PLZT 박막에 ±5V 의 사각펄스를 $10^9$ 회 인가하여 피로특성을 측정한 결과, PLZT(10/40/60) 박막의 잔류분극은 초기분극값으로부터 50% 감소된 반면, PLZT(10/0/100) 박막은 30% 감소되었다. 또, $10^5$ 초의 retention 결과에서 PLZT(10/0/100) 박막은 초기분극값에서 오직 11% 만이 감소된 반면, PLZT(10/40/60) 박막은 40% 감소되었다.

• Journal of Sericultural and Entomological Science
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• v.39 no.2
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• pp.180-185
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• 1997

To develope the novel baculovirus transfer vector, the p10 gene was cloned from the Bombyx mori nuclear polygedrosis virus (BmNPV) vB2 strain isolated from the B. mori larvae of sericultural farms. The novel transfer vector was constructed by using the p10 gene of BmNPV vB2 strain was 210 bp. The TAAG sequence at the -71 bp of upstream from translation initiator ATG and two polyadenylation signal site at the downstream from terminator TAA were also detected in the p10 gene. The 5' and 3' flanking region of the p10 gene amplified by PCR was cloned into pBluescriptII SK(+) and then transfer vector pBm10 was construceted. The 7.9 kb pBm10 was analysed by restriction enzymes and the map was confirmed. In order to determine the expression of foreign gene of pBm10, $\beta$-galactosidase gene was inserted in the SmaI site of foreign gene cloning site of pBm10. The pBm10 containing $\beta$-galactosidase gene was cotranfected wth genomic DNA of BmNPV vB2 into BmN-4 cells. The recombinant baculovirus expressing $\beta$-galactosidase was also produced polygedra in the infected cells. The results indicated that pBm10 is functional, suggesting that in the baculovirus expression vector system, the recombinant virus produced by pBm10 was effective by oral infection for the producing recombinant proteins in in vivo expression.

• ALGAE
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• v.26 no.1
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• pp.79-86
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• 2011

Physiological studies on the hybrid by crossing between two dioecious species, Porphyra pseudolinearis and P. dentata from Korea were conducted at constant temperatures (5, 10, 15, 20, and $25^{\circ}C$), at photon flux densities (10, 20, 40, and $80\;{\mu}mol\;m^{-2}s^{-1}$) under photoperiods (14 L : 10 D and 10 L : 14 D). In the hybrid, higher growth of conchocelis was observed at 20 and $40\;{\mu}mol\;m^{-2}s^{-1}$ under 14 L : 10 D. Conchosporangial branches were produced under $10-80\;{\mu}mol\;m^{-2}s^{-1}$ at only $25^{\circ}C$, and were abundant when the conchocelis was cultured under 10 L : 14 D. Foliose thalli of the hybrid grew well at the conditions of $10-20^{\circ}C$, 10 L : 14 D and $15-20^{\circ}C$, 14 L : 10 D. The foliose thalli grew very slowly at $5^{\circ}C$ and $30^{\circ}C$, respectively. No archeospores were observed at any culture conditions. Spermatangial and zygotosporangial sori were formed at the marginal portion of mature thallus. Zygotospores from the hybrid were released at $10-2^{\circ}C$ under both photoperiods, and gave rise to form conchocelis filament. Monoecious thalli were observed at $10^{\circ}C$ under 14 L : 10 D. Neither monospores nor protothalli were produced from the conchocelis in culture.

• Applied Biological Chemistry
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• v.33 no.1
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• pp.39-42
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• 1990

The properties of amylose of cow pea starch were investigated. Amylose content of cow pea was 25.1 % and iodine binding capacity was 20.2 %. The ${\beta}-amylolysis$ limit of the amylose was 82.3%. The limiting viscosity number of the amylose fraction was 204 ml/g and the corresponding average degree of polymerization was 1,510 glucose units. The percent distribution of molecular weight of the amylose by gel chromatography was $1{\times}10^4$(0.7 %), $1{\times}10^4{\sim}4{\times}10^4$(4.1 %), $4{\times}10^4{\sim}5{\times}10^5$(44.6 %), $5{\times}10^5{\sim}4{\times}10^7$(49.6 % ).

• The Korean Journal of Pesticide Science
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• v.4 no.4
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• pp.77-80
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• 2000

This study was carried out to investigate infection process, symptoms and $LD_{50}$ values of the entomopathogenic fungus cordyceps, Paecillomyces japonica, on the domestic silkworm, Bombyx mori. Susceptibility of infection in the silkworms by cordyceps, Paecillomyces japonica, was 100% in $10^{7}$ block, 96% in $10^{6}$ block, 76% in $10^{5}$ block, 44% in $10^{4}$ block, 28% in $10^{3}$ block and 8% in $10^{2}$ block. Cordyceps, Paecillomyces japonica, was highly infectious to the silkworms. A pathogenicities of cordyceps, Paecillomyces japonica, may be highly virulent because of the low resistance or high susceptibility of the silkworms. Dosage of the pathogen of $LD_{50}$ was $3.78{\times}10^{3}\;spores/mm^{3}$.

• Journal of Environmental Science International
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• v.13 no.1
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• pp.27-36
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• 2004

Present study analyzed the temporal and spatial characteristics of PM10 pollution in Metropolitan Daegu area based on air pollution monitoring station data and measurements of PM10 concentrations in background area in order to provide essential data for efficient PM10 pollution management. The significant variation of spatial and temporal PM10 concentrations in Daegu area was observed during the study years. The highest maximum PM10 concentration(332 $\mu\textrm{g}$/㎥), average concentration(88 $\mu\textrm{g}$/㎥) and frequency exceeding PM10 daily standard(150 $\mu\textrm{g}$/㎥) were all observed in Namsandong located near a major roadway. The hourly and weekly variations of PM10 concentrations had different pattern for the measurement sites. The monthly and seasonal concentrations exhibited a notable characteristic： the maximum concentration was obtained in spring season, most likely due to Yellow sand effects. Furthermore, this temporal variation of PM10 pollution varied with study site. Meanwhile, the PM10 values measured at the monitoring site, Manchondong, were comparable with those of a control site. The average PM10 concentration ranged from 23 $\mu\textrm{g}$/㎥ to 115 $\mu\textrm{g}$/㎥ with a mean value of 53 $\mu\textrm{g}$/㎥ in the former site and from 22 $\mu\textrm{g}$/㎥ to 91 $\mu\textrm{g}$/㎥ with a mean value of 45 $\mu\textrm{g}$/㎥ in the latter site.

• Journal of Advanced Marine Engineering and Technology
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• v.23 no.6
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• pp.770-777
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• 1999

In this study a phase diagram has been used to investigate the unsteadiness of two-dimensional lid-driven closed flows within a square cavity for twelve Reynolds numbers; $7.5{\times}10^3,\; 8{\times}10^3,\; 8.5{\times}10^3,\; 9{\times}10^3,\; 9.5{\times}10^3,\; 10^4,\;1.5{\times}10^4,\;2{\times}10^4,\; 3{\times}10^4,\; 7.5{\times}10^4$ and $10^5$. The results indicate that the first critical Reynolds number at which the flow unsteadiness of sinusoidal fluctuation appears from the temporal variation of total kinetic energy curves is assumed of sinusoidal fluctuation appears form the temporal variation of total kinetic energy curves is assumed to be in the neigh-bourhood of $Re=8.5{\times}10^3$ The second critical Reynolds number where the periodic amplitude and frequency collapse to random disturbance being existed around $Re=1.5{\times}10^4$ The exponentially decreasing vortices formed at the lower two corners are found commonly at the time-mean flow pattern of $Re=3{\times}10^4$.

• Journal of Food Hygiene and Safety
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• v.13 no.1
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• pp.1-5
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• 1998

This study was carried out to measure the antibacterial effect of lactoperoxidase/ thiocyanate/hydrogen peroxide system (LP system) against E. coli 0157:H7. When the initial inoculum levels (($10^{2},\;10^{4},\;10^{7}cfu/ml$), concentration of LP (10 ppm, 20 ppm, 30 ppm), culture media (TSB-YE, UHT milk, raw milk) and storage temperatures ($5^{\circ}C,\;10^{\circ}C,$15$^{\circ}C$) were set up differently for the experiment and the antibacterial effect was compared, the highest antibacterial effect of LP system was shown at $10^{2}cfu/ml$ of initial inoculum level, 10 ppm of LP concentration and $5^{\circ}C$ of incubation temperature.

• Journal of Food Hygiene and Safety
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• v.13 no.2
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• pp.83-86
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• 1998

This study was carried out to measure the antibacterial effect of lactoperoxidase system against L. monocytogenes. When the initial inoculum levels ($10^{2},\;10^{4},\;10^{7}\;CFU/ml$), concentration of LP (10 ppm, 20 ppm, 30 ppm), culture media (TSB-YE, UHT milk) and storage temperatures ($5^{\circ}C,\;10^{\circ}C,\;15^{\circ}C$) were set up differently for the experiment and the antibacterial effect was compared, the highest antibacterial effect of LP system was shown at $10^{2}\;cfu/ml$ of initial inoculum level, 10 ppm of LP concentration and $5^{\circ}C$ of incubaction temperature. The antibacterial effect of LPS in UHT milk was similar to that in Tryptic soy broth.

• Korean Journal of Soil Science and Fertilizer
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• v.32 no.3
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• pp.279-284
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• 1999

Fly ash is the fine ash particles that are flying out of chimney of the thermoelectric power plant where coals are used as fuel. There are two kinds of fly ashes from anthracite and bituminous coal. By scanning electron microscope(SEM) morphological feature of fly ash was confirmed to the exact spherical particles with the diameter variation from the fine to the largest about $50{\mu}m$(mainly silty particle). Surface of anthracite ash particle was very smooth but that of bituminous was somewhat coarse. To find the utilization of fly ash for improving soil permeability, soils of 4 kinds of different texture, clay, clay loam, sandy clay loam and sand mere applied with 7 levels of fly ash: 0, 10, 20, 40, 60, 80, 100%(w/w) and their saturated hydraulic conductivity(Ks) were determined at each application by constant head method. In clay soil with low water permeability, Ks value was increased about 10 times from $10^{-8}$ to $10^{-7}m\;s^{-1}$ level with application of 10% fly ash and it was slightly increased with increasing fly ash application from 40 to 80%. In clay loam Ks value was about $10^{-7}m\;s^{-1}$ level and its value was not influenced by the fly ash application. In sandy clay loam with relatively high permeability, Ks value was decreased about 10 times from $10^{-5}$ to $10^{-6}m\;s^{-1}$ level with application of 10% fly ash and also decreased about 50 times from $10^{-5}$ to $5.0{\times}10^{-7}m\;s^{-1}$ with application of more than 20% fly ash. In sand with very high permeability, Ks value was decreased about 10 times from $10^{-4}$ to $10^{-5}m\;s^{-1}$ level with application of 10% fly ash and also decreased about 100 times from $10^{-4}$ to $10^{-6}m\;s^{-1}$ level with application of 20% fly ash and continuously decreased about 500 times from $10^{-4}$ to $5.0{\times}10^{-7}m\;s^{-1}$ level with application of more than 40% fly ash. In conclusion by fly ash application saturated hydraulic conductivity was increased in clay soil, on the contrary it was decreased in sandy soils. Fly ash may be used as a material for amelioration of soil permeability.