• The Plant Pathology Journal
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• 제21권1호
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• pp.68-72
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• 2005

The production of antibiotic substances by Serratia plymuthica A21-4 was greatly enhanced by modifying components of a growth medium. When the minimal medium containing $K_2HPO_4$ 0.7%, $KH_2PO_4$ 0.2%, $(NH_4)_2SO_4$ 0.1%, $MgSO_4$ 0.01% was used as basal medium, the best carbon source for antibiotic production was glycerol and the most favorable nitrogen source was ammonium sulfate. The modified medium for antibiotic production also increased colonization ability of A21-4 on pepper root and in the rhizosphere soil. When the cells of A21-4 were suspended in modified medium, the population density of A21-4 on pepper root was 10-100 times higher than that suspended in 0.1 M $MgSO_4$. The population density of A21-4 on root did not decrease under $10^6$ cfu/groot up to 21 days after treatment although the inoculum of A21-4 was reduced to $10^7$ cell/ml. Similar tendency was also observed in the rhizosphere soil. Consequently, Phytophthora blight of pepper was successfully controlled by A21-4 with $10^7$ cell/ml suspended in the modified buffer solution instead of $10^9$ cfu/ml suspended in 0.1 M $MgSO_4$.

• 대한치과교정학회지
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• 제21권3호
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• pp.635-656
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• 1991

It was the aim of this investigation to evaluate some histologic aspect of rat pulp tissue after it had been compromised by an experimental orthodontic force. Experimental animals of thirty five Spraque-Dawley rats were employed. The first upper molars had been successively mesial moved (initial load 100 gr.) with a closed coil spring during 21 days. The experimental periods were set on immediate, 1 day, 1 week, 2 weeks, 3 weeks, 4 weeks following retention time. On each experimental period, the rats were killed and prepared for the light microscopy. After prepared with H/E stain and Gomori's one-step trichrome stain, the specimens were analyzed with evaluation criteria which were adopted in this study. The result may be summarized as follows; 1. The main pulp changes due to experimental orthodontic force included vacuolization of odontoblastic layer, circulation disturbance, root resorption, reduced pulp collagenous fiber density and mean cell count of pulp fibroblast in the immediate group. 2. The pulp tissue changes were revealed reversible because the relieved pulp tissues from experimental orthodontic force were recovered rapidly in each evaluation criteria during retention periods. 3. Compared with normal control group, pulp collagenous fiber density were decreased in immediated group (p < 0.01), but increased in each retention groups. These seem to suggest that the pulp tissues were aged after experimental orthodontic force conditions. 4. Compared with normal control group, mean cell counts of pulp fibroblasts were decreased in immediate group (p < 0.05), but increased continuous in each retention groups. These seem to indicate that the pulp tissues were highly regenerative after experimental orthodontic force conditions. 5. Compared with normal control group, root resorptions occurred in all immediate specimens (p < 0.01) and they were healed in each retention periods, but often observed in 4 weeks retention group. These seem to indicate that root resorptions were recovered slowly after experimental orthodontic force conditions.

• Nuclear Engineering and Technology
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• 제29권5호
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• pp.375-384
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• 1997

Relative power density distributions of the Kori Unit 1 pressurized water reactor are calculated by Monte Carlo modeling with the MCNP code. The Kori Unit 1 core is modeled on a three-dimensional representation of the one-eighth of the reactor in-vessel component with reflective boundaries at 0 and 45 degrees. The axial core model is based on half core symmetry and is divided into four axial segments. Fission reaction density in each rod is calculated by following 100 cycles with 5,000 test neutrons in each cycle after starling with a localized neutron source and ten noncontributing settle cycles. Relative assembly power distributions are calculated from fission reaction densities of rods in assembly. After 100 cycle calculations, the system converges to a k value of 1.00039 $\geq$ 0.00084. Relative assembly power distribution is nearly the same with that of the Kori Unit 1 FSAR. Applicability of the full-scope Monte Carlo simulation in the power distribution calculation is examined by the relative root moan square error of 2.159%.

• 약학회지
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• 제45권5호
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• pp.529-536
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• 2001

The root of Astragalus membranaceus Bunge (Leguminosae), which has been used for the treatment of hypertension, chronic hepatitis, duodenal ulcers, chronic nephritis and promotion of immunity in folk remedies. Several lines of evidence indicate that oxidative modification of low-density lipoprotein (Ox-LDL) may play an important role in atherogenesis. Hence, the role of antioxidants in the prevention of LDL oxidation needs to be determined. To investigate the antioxidant activity. we determined the MeOH ex. and fractions of Astragali Radix on the inhibition of LDL oxidation. The CH$_2$C1$_2$ and EtOAc orations inhibited the oxidative modification of LDL by a decrease in the lipid peroxide content and the electrophoretic mobility of LDL. Calycosin-7-0-$\beta$-D -glucoside which was isolated from EtOAc fraction inhibits the oxidative modification of LDL.

• 반도체디스플레이기술학회지
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• 제20권4호
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• pp.146-150
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• 2021

Plasma information based virtual metrology (PI-VM) that predicts wafer-to-wafer etch rate variation after wet cleaning of plasma facing parts was developed. As input parameters, plasma information (PI) variables such as electron temperature, fluorine density and hydrogen density were extracted from optical emission spectroscopy (OES) data for etch plasma. The PI-VM model was trained by stepwise variable selection method and multi-linear regression method. The expected etch rate by PI-VM showed high correlation coefficient with measured etch rate from SEM image analysis. The PI-VM model revealed that the root cause of etch rate variation after the wet cleaning was desorption of hydrogen from the cleaned parts as hydrogen combined with fluorine and decreased etchant density and etch rate.

• 생물환경조절학회지
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• 제16권3호
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• pp.217-221
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• 2007

다양한 활엽수 자원의 개발에 필요한 기초자료를 제공하고자 쪽동백나무 유묘의 생육밀도에 따른 물질생산량과 생장특성 등 최적의 생장조건을 조사하였다. 묘목의 생육밀도는 수고생장에 크게 영향을 미치는 중요한 요인이 될 수 있으며, 본 실험 결과 쪽동백나무의 $1m^2$당 생육 밀도에 따른 묘목의 생장은 49본구에서 간장과 근원직경이 우수한 생장량을 보인반면 생육밀도가 낮은 처리구는 근원직경 생장이 증가하면서 간장생장은 떨어지는 경향을 보였다. 물질생산량 또한 생장 특성과 마찬가지로 $1m^2$당 49본구 처리구에서 전체 물질생산량이 통계적으로 유의적인 차이를 보이면서 $3.12{\pm}0.80g$로 다른 처리구보다 높은 물질생산량을 보였고, T/R율에서도 1.59로 나타났다. 생리적 특성으로 광합성률 또한 쪽동백나무의 경우 $1m^2$당 $49/m^2$ 본구와 $64/m^2$ 본구에서 상대적으로 높은 광합성률을 보였고 밀도가 높아질수록 광합성 효율이 떨어지는 결과를 나타냈다. 이는 생육 환경조건에서 적절한 공간 확보가 궁극적으로 최종 물질대사 작용인 광합성률 변화에서 최적의 상태를 보이면서 생리적으로 안정된 생장형태를 보이는 것으로 판단되며, 적정 공간의 장애가 실질적인 생장저하를 발생시키고, 궁극적으로 물질대사의 최고 단계인 광합성효율 또한 낮아지는 경향을 나타냈다.

• Weed & Turfgrass Science
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• 제7권2호
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• pp.148-157
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• 2018

본 연구는 외국산 피트를 포함해서 국내외 토양개량재 4종류가 크리핑 벤트그래스의 초기 활착 및 잔디밀도에 미치는 영향을 조사함으로 잔디밭 조성 시 실무에 활용할 수 있는 기초자료를 얻기 위해 수행하였다. 전체 20개 처리구는 식재층 모래에 유기질 토양개량재인 SABP (Berger peat), SAEP (Eco-peat), SAGS (G1-Soil) 및 SAPP (Premier peat)를 10-50% (v/v) 사이 혼합하여 준비하였다. 크리핑 벤트그래스의 초기 활착 및 밀도 변화는 토양개량재 종류에 따라 유의한 차이가 나타났다. 잔디밀도는 경시적인 변화가 나타나서 파종 2주 후 생육 초기 최저 36.7% (SABP 30)에서 최고 89.7% (SAGS 20)까지 처리구간 차이가 53% 정도 나타났다. 하지만 파종 6주 전후로 성숙기 밀도 수준에 도달해서 SABP 및 SAEP 일부 혼합구를 제외한 대부분 처리구에서 잔디밀도는 90% 전후로 비슷하였다. 실험 종료 시 최종 활착율은 최저 60.7% (SAEP 10)에서 최고 96.7% (SAPP 50)까지 처리구간 차이가 36.0%나 크게 나타났다. 잔디 활착율 및 밀도에 대한 최적 혼합율은 개량재 종류에 따라서 일정하지 않았다. SABP와 SAGS 개량재의 최적 혼합비율은 각각 10% 및 20%로 나타났지만, SAEP와 SAPP 개량재는 50%가 최적의 비율로 나타났다. 따라서 잔디밭 조성 전에 과학적인 분석을 통해 개별 토양개량재의 적정 혼합비율을 결정해서 실무에 적용하는 것이 필요하며, 또한 향후 주요 잔디 초종에서 외국산 및 국내산 토양개량재가 잔디생육에 미치는 종합적인 포장 적응성 실험을 통해 실무 응용에 활용하는 것이 바람직하다.

• 한국약용작물학회지
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• 제2권1호
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• pp.26-31
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• 1994

토천궁(土川芎)의 재식밀도(栽植密度)가 생육(生育) 및 수양(收量)에 미치는 영향(影響)을 조사(調査) 분석(分析)하여 재배기술개선(栽培技術改善)을 위한 자료(資料)로 이용(利用)하고자 시험한 결과(結果)를 요약(要約)하면 다음과 같다. 1. 주당(株當) 경수(莖數)와 엽수(葉數), 주경분지수(株莖分枝數)는 밀식(密植)할 수록 감소되었지만 단위면적당 경수(莖數)와 엽수(葉數), 주경분지수(株莖分枝數)는 증가되었다. 2. 경장(莖長)은 밀식(密植)할 수록 커졌으나 $50{\times}10cm$에서는 약간 작아졌으며 경태(莖太)는 재식밀도간(栽植密度間)에 큰 차이가 없었고 지표면에서 1차분지(分枝)까지의 높이는 밀식(密植)할 수록 높아졌으나 유의성은 인정되지 않았다. 3. 지상부(地上部)와 지하부(地下部) 생육특성(生育特性)은 $m^2$당 경수(莖數)가 많으면 주당(株當) 엽수(葉數)와 주경분지수(株莖分枝數)가 적어지고, $m^2$당 경수(莖數)와 엽수(葉數), 주경분지수(株莖分枝數)가 많아지면 지표면에 서의 1차분지착생(分枝着生)높이가 높아졌다. 4. 10a당 근경수양(根莖收量)은 주당(株當) 경수(莖數)와 엽수(葉數)와는 유의적인 부(負)의 상관(相關)이 인정되었으며, $m^2$당 경수(莖數)와 엽수(葉數), 주경분지수(株莖分枝數)와는 유의적인 정(正)의 상관(相關)이 인정되었다. 5. 개체당(個體當) 근경중(根莖重)과 세근중(細根重)은 밀식(密植)할 수록 작아졌으며 10a당 근경(根莖)과 세근(細根)의 수양(收量)은 오히려 밀식(密植)할 수록 증가되었다.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제55권3호
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• pp.156-160
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• 2006

In whole world consciousness of environment maintenance have increased very quickly for the end of the 20th century. To use and disuse toxic substances have been controled at the field of industry. Also the field of lighting source belong to environmental control. And in the future the control will be strong. In radiational mechanism of fluorescence lamp mercury is the worst environmental problem and root. In the mercury free lighting source system the Xe gas lamp is one type. And the Ne:Xe and Ne:Ar mixed gas lamp improve firing voltage of Xe gas lamp. Purpose of this study is to understand ideal mixing-ratio of Ne:Xe and Ne:Ar gas by electron temperature and electron density for mercury free lamp. Before ICP was designed, basic parameters of plasma, which are electron temperature and electron density, were measured and calculated by single-Langmuir probe. Property of electron temperature and electron density were confirmed by changing ratio of Ne:Xe and Ne:Ar.

• 새물리
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• 제68권12호
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• pp.1324-1330
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• 2018

The elastic scatterings for the ${\alpha}+^{40}Ca$ and the ${\alpha}+^{58}Ni$ systems at $E_{lab}=240MeV$ have been analyzed within the framework of the Coulomb-modified Glauber model using two kinds of Gaussian density parameters for the target nuclei. The first one is to use Gaussian density parameters obtained from the root-mean-square radius. The second one is to use parameters calculated by matching the Gaussian density to the two-parameter Fermi density. The results with surface-matched Gaussian densities provide reasonable agreement with the experimental data, but the results without matching do not. The oscillatory structures observed in the angular distributions of both system can be interpreted as being due to the strong interference between the near-side and the far-side scattering amplitudes. The differences between the phase shifts obtained from the two methods are examined. We also investigate the effect of these differences on the differential and reaction cross sections, the transmission functions and the strong absorption radii.