• 한국생물공학회:학술대회논문집
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• 2000.11a
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• pp.701-702
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• 2000

The thiolated anti-Escherichia coli antibody prepared by thiolation with a thiolcleavable heterobifunctional cross-linker, sulfosuccinimidyl 6[3- (2-pyridyldithio) propionamido]hexanoate (sulfo-LC-SPDP) was chemisorped onto one gold electrode of the piezoelectric quartz crystal surface. In the QCM system employing a batch-type well holder, a steady-state frequency decrease was attained within 20 min when $100{\sim}200\;{\mu}L$ suspensions of Escherichia coli having viable cell counts of $10^5{\sim}10^6\;CFU/mL$ were added. The stability of sensor response was improved compared to the system with a batch-type dip holder.

• Journal of the Optical Society of Korea
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• v.20 no.4
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• pp.510-514
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• 2016

The conventional liquid crystal displays (LCDs) have been using optically uniaxial liquid crystal (LC) medium and this often causes a significant image change at oblique viewing angles. We simulated the viewing angle properties of the biaxial nematic (N_b) phase of a bent-core liquid crystal (BLC) and compared the results with the vertically aligned (VA)- and the in-plane switching (IPS)-LCDs. The N_b phase of the BLC showed a smaller transmittance at the dark state as well as a greater contrast ratio at wide viewing angle. The viewing angle property of the N_b-mode without any compensation film was slightly superior to the IPS-mode with the compensation films eliminating the decross of the polarizers at oblique viewing angle.

• Journal of the Korean Magnetic Resonance Society
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• v.20 no.2
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• pp.41-45
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• 2016

Chemical investigation of a marine-derived fungus, Penicillium sp. 108YD020, resulted in the discovery of six bile acid derivatives, glycocholic acid (1), glycocholic acid methyl ester (2), cholic acid (3), glycochenodeoxycholic acid (4), glycodeoxycholic acid methyl ester (5), and cholic acid methyl ester (6). The structures of six bile acid derivatives 1-6 were determined by the detailed analysis of 1D, 2D NMR and LC-MS data, along with chemical methods and literature data analysis.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.3
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• pp.395-400
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• 2000

양파 조미액으로부터 ACE 저해활성 물질을 분리하기 위해 hexane, ethylether, ethylacetate, butanol과 물로 분획시, 4.8g의 당 함량과 31.9 mg의 phenol성 물질을 함유한 butanol 분획이 82.1%의 ACE 저해활성을 나타내었고, 70.3%의 ACE 저해활성을 보인 양퍄 조미액보다 높은 저해활성을 보였다. Butanol 분획을 Amberite XAD-2column으로 분리한 결과, ACE 저해활성을 보이는 미흡착 분획(F1)를 얻었다. 활성분획 F1을 Sephadex LH-20column으로 분획한 결과, 4개(F1-1,F1-2,F1-3,F1-4)의 분획을 얻었으며, 이중 F1-3 분획의 ACE 저해활성은 93%로 가장 높은 저해활성을 보였다. Sephadex LH-20 column chromatography에 의해 얻어진 활성분획F1-3을 Supercosil LC-18 column을 이용하여 분리한 결과, 6분대에서 ACE 저해활성을 가지는 단일 peak(F1-3a)를 얻었다. 각 정제 과정에서 얻은 분획들은 전형적인 flavonoid의 band I과 bandII의 피크를 보였다. 또한 ACE에 대한 저해기작은 flavonoid 물질이 보이는 전형적인 비경쟁적 저해양상을 보였다.

• Environmental Analysis Health and Toxicology
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• v.21 no.4 s.55
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• pp.311-316
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• 2006

미꾸리(Misgurnus anguillicaudatus)에 대한 4가지 농약(diazinon, carbaryl, fenpropathrin, myclobutanil)의 급성독성을 평가하기 위하여, 치어 및 자어 단계(postlarva I, postlarva II, 8 WPH(weeks posthatch), 16 WPH, 20 WPH, 32 WPH, 40 WPH)의 미꾸리를 사용하여 급성독성실험을 실시하였다. 각 생육단계 별로 구해진 각 실험농약의 96-hr $LC_{50}$값을 비교하여 미꾸리에 대한 급성독성이 높은 순서를 정리한 결과는 Fenproparthri>Diazinon>Carbaryl, Myclobutanii 순으로 나타났다. 또한, 본 연구에서 사용된 4가지 농약의 독성은 미꾸리의 생육단계에 따라 차이를 나타냈다. 농약에 대한 감수성이 민감한 미꾸리의 생육단계 순으로 정리하면 Postlarva I>Postlarva II, 8 WPH>16 WPH, 20 WPH, 32 WPH, 40 WPH 나타났다. 그러므로 환경관리 및 규제목적으로 미꾸리 성체를 사용하여 독성실험을 할 경우에는 독성을 과소평가 할 수도 있음을 보여주었다.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.20 no.12
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• pp.1068-1071
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• 2007

When a dielectric layer, in-cell retarder (ICR) is formed between electrode and LC layer to get a single gap transflective fringe-field switching (FFS) display, the operating voltage ($V_{op}$) is highly increased due to the thickness of dielectric material. But, we also knew the phenomenon that the increasing rate of Vop is different whether the 1st common electrode was composed of plate type or slit type. In this paper, the common electrode in transmissive part was composed of slit type which had less steepness effect of the Vop and in reflective part was composed of plate type. The rubbing angle of reflective part can be adjusted properly to match the voltage dependent transmittance and reflectance.

• Proceedings of the KIPE Conference
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• 2001.07a
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• pp.589-593
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• 2001

This paper presents a high frequency modulation electronic ballast for the metal halide lamp. As the proposed ballast operates in high frequency ranges (20kHz - 100kHz) and it can start up the lamp using the LC resonant circuit without external igniter, the proposed ballast is very compact. The proposed ballast is controlled with the modulated frequency in the range of 20kHz to 100kHz, and it has variable modulating frequencies between 200Hz and 2kHz in order to avoid the acoustic resonance phenomenon. In this paper, a new realtime acoustic resonance detection method is described and the experimental results with the proto-type ballast of 150W metal halide lamp with the dimming function are discussed.

• Bulletin of the Korean Chemical Society
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• v.20 no.4
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• pp.427-430
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• 1999

The Grignard coupling reaction of bis(chloromethyl)diorganosilanes [(ClCH2)2SiR1R2: R1 = R2 = Me, la; R1 = Me, R2 = Ph, lb; R1 = R2 = Ph, lc] with diorganodichlorosilanes [(Cl2SiR3R4: R3 = R4 = Me, 2a; R3 = Me, R4 = Ph, 2b; R3 = R4 = Ph, 2c] at THE reflux temperature gave the intermolecular C-Si coupling product of 1,1,3,3-tetraorgano-1,3-disilacyclobutanes 3a-f in poor to moderate yields ranging from 7% to 50% along with polydiorganosilapropanes. The cyclization reaction of la-c with methyl-substituted dichlorosilanes 2a, b gave 1,3-disilacyclobutanes 3a-c, e, d in moderate yields (42-50%), while the same reaction with dichlorodiphenylsilane (2c) to 1,3-disilacyclobutanes 3d, f resulted in low yield (7-18%) probably due to the steric hindrance of two-phenyl groups on the silicon of 2c.

• Korean journal of applied entomology
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• v.40 no.1
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• pp.59-67
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• 2001

The potential of two entomopathogenic nematodes, Sreinernema carpocapsae Pocheon strain and Heterorhabditis bacteriophora Hamyang strain as biological control agents was evaluated against mushroom ny, Lycoriella mali in laboratory and field. Mortality of L. mali was significantly different according to nematode species, concentration, temperature, and developmental stage of fly S. carpocapsae was more effective than H. bacteriophora. Mortality of L. mali was higher at $25^{\circ}C$ than at $20^{\circ}C$. In addition, the 3rd instal and the 4th instar of L. mali were more susceptible than the 2nd instar. The lowest $LC^{50}$ value was represented by S. carpocapsae, 20.0 infective juveniles (Ijs) in the 3rd instar, 27.5 Ijs in the 4th instar at $25^{\circ}C$. S. carpocapsae infected all the developmental stages of L. mali except egg stage and the 1st instar of larva. The highest mortality was shown in adult female representing 74.0% at$20^{\circ}C$ and 80.0% at $25^{\circ}C$.L. mali female adult was influenced by S. carpocapsae in oviposition. The number of eggs by L. mali female infected by nematodes was much lower than uninfected females. S. carpocapsae was dispersed by infected L. mali adult with higher numbers by females than males. When S. carpocapsae was applied at the rate of $2.25{\times}10^{5}\;and\;4.5{\times}10^{5}\;Ijs/1.5\;\textrm{m}^2$ in the mushroom house, mortalities were 42.2% and 81.6%, respectively. The infective juveniles of nematodes survived for 14 days in the mushroom medium. However, nematodes did not affect mushroom growth.

• Korean journal of applied entomology
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• v.25 no.3 s.68
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• pp.151-157
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• 1986

Population of the green peach aphid, Myzus persicae(Sulz.), were successively selected(up to 20th generation) in the laboratory by the insecticide oxydemeton-methyl (Metasystox-R 25Ec) and the resistance was linearly increased with the selected generations. The population developed 355.5-to 359.9-fold resistance to oxydemeton-methyl at 20th generation-selection. The population showed cross resistance to the insectides cypermethrin(770.1-to 778.5-fold), acephate(25.6-to 33.2-fold) and pirimicarb(3.4-to 3.6-fold). The different esterase isozymes were detected by the electrophoresis from the selected and non-selected strains and the band of the ${\beta}-2$ from the selected strain showed greater esterase activity than that of the non. selected strain.