• Bulletin of the Korean Chemical Society
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• v.28 no.10
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• pp.1797-1802
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• 2007

The kinetics and mechanism of the nucleophilic substitution reactions of diphenyl phosphinic (1) and thiophosphinic (2) chlorides with substituted X-pyridines are investigated kinetically in acetonitrile at 35.0 and 55.0 oC, respectively. A concerted mechanism with backside nucleophilic attack is proposed for the pyridinolysis of 1, on the basis of the linear Bronsted plot with the βX value of 0.68. In the case of the pyridinolysis of 2, the Hammett and Bronsted plots are biphasic concave upwards with the break point at 3- phenyl pyridine. These results indicate a change in mechanism from a concerted SN2(P) process with direct backside nucleophilic attack for less basic nucleophiles (X = 3-CN-3-Ph) to a stepwise process with frontside attack for more basic nucleophiles (X = 4-MeO-3-Ph). Apparent secondary inverse kinetic isotope effects with deuterated pyridine (C5D5N), kH/kD < 1, are observed for the pyridinolysis of 1 and 2.

• Journal of fish pathology
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• v.21 no.3
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• pp.209-217
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• 2008

A disease with mass mortality characterized exophthalmia and abdominal distension by ascites occurred in farmed starry flounder, Platichthys stellatus in Pohang since October of 2007. Severe necrosis and infiltration of inflammatory cells were observed in tissue histopathological sections from liver, kidney, spleen and heart of the diseased fish. The catalase-negative and gram positive cocci with -hemolysis were isolated from moribund fish. Analysis of the API profiles and the multiplex PCR of the isolates showed that strains were identified as Streptococcus parauberis. In API profiles, S. parauberis isolated from starry flounder differed from those of olive flounder, Paralichthys olivaceus to the test of arginine dihydrolase, D-mannitol, D-sorbitol and α-lactose. And the strains, PH0710 and PH0711, were strongly lethal for starry flounder (LD50 ranging from 4.2×103~4.2×102 cfu/fish at 7 days after intraperitoneally inoculation). This is the first report on a S. parauberis infection in starry flounder.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.05b
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• pp.119-122
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• 2003

The purpose of this study is to find problems of "Electricity equipmentand" and "Electricity practic II" tectbook applied in 6th Technical High School Curriculum and to make direction of "Power equipment II" textbook applied in 7th Technical High School Curriculum. The method of this study is questionnaire survey. 120 teachers of 40 schools were selected by cluster sampling method. The main findings of this study are as follow. 1) We should make the composition of textbook easy. 2)The illustration, photograph and drawing of textbook are fitted well. 3) "power equipment II" textbook applied in 7th Technical High School Curriculum would contented follows : lighting equipment, elevator equipment, broadcasting equipment, interphone equipment.

• The Journal of Information Technology
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• v.7 no.3
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• pp.99-112
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• 2004

Internet is changing all of the commercial practices and customs on international business transaction. So called e-Trade in global marketing is expected to dominate the global trade in 21st century and thus is being introduced as a major mission assignment for exporting countries. e-Trade has the potential to accelerated existing threads and introduce new ways of carrying out global trade. It is especially important in Korea, which has a high dependency rate on trade. Trade efficiency through the channel of e-Trade is an alternative to strengthen international competition of korean small and medium sized global trading firm.

• Journal of the Korean Institute of Telematics and Electronics D
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• v.35D no.7
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• pp.25-31
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• 1998

Modal transmission-line is utilized to analyze the power coupling of optical directional coupler composed by two parallel guiding slabs. By defining a coupling efficiency .eta. amenable to rigorous supermodes and boundary conditions of modal functions, we evaluate the power transfer for TE mode of gainy coupler. The results reveal that optimized power exchange occurs at a novel wavelength .lambda.$_{op}$ , which is generally different from minimum gap .lambda.$_{min}$ between rigorous modes and phase-matching condition .lambda.$_{ph}$ .

• Proceedings of the Korean Society of Applied Pharmacology
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• 1993.04a
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• pp.111-111
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• 1993

Anthracycline의 합성에 있어서 aglycone 뿐만 아니고 sugar도 대단히 중요한 역할을 한다. Anthracycline에 이용되는 sugar인 daunosamine의 전합성의 확립을 통하여 daunosamine의 anlogue을 합성할 목적으로 daunosamine의 전합성을 검토하고 있다. Methyl D-mannopyranoside을 원료로 하여 0-methylation, PhCH(OMe)$_2$ 에 의한 OH의 보호, n-BuLi을 이용한 위치선택적 deblocking, oxime생성, 이어서 Vitride를 이용한 환원으로 daunosamine 합성에 있어서 중요한 중간체인 methyl-3-amino-4,6-benzylidene-2,3-dideoxy-$\alpha$-D-hexopyranoside을 합성하였다.

• Weed & Turfgrass Science
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• v.3 no.1
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• pp.41-49
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• 2014

Four preparations of liquid turfgrass fertilizers were tested cool season turfgrasses during fall season. The preparations of PS-A, PS-B, PH-C and PH-D for commercial products were contained with essential nutrient elements, seaweed extract, amino acids, and humus substance. Growth and quality of creeping bentgrass (Agrostis palustris Huds cv. Penn-A1) and Kentucky bluegrass (Poa pratensis L.) mixture (Midnight 33%, Moonlight 33%, Prosperity 33%) were evaluated by normalized difference vegetation index (NDVI), root length and fresh weight, shoot density, turf color, and chlorophyll content. Three foliar sprays of 4 preparations with an interval of 7 days were made in the fall of 2013 in the sod production field at Hapchun, Korea. No significant difference among 3 preparations was found in NDVI of creeping bentgrass. However, PS-A was significantly increased NDVI of Kentucky bluegrass. Two to three applications of PS-A significantly increased chlorophyll content and turf color. Three foliar sprays of PS-A and PS-B were significantly increased the shoot density of Kentucky bluegrass on 20 days after final application. These results may indicate that the use of some preparation is beneficial in producing higher quality turfgrass sod with better color and chlorophyll content during fall season.

• Food Science of Animal Resources
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• v.29 no.6
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• pp.719-725
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• 2009

Heterocyclic aromatic amines (HCAs) are potent mutagens and possible human carcinogens that are formed during the heating of protein-rich foods. The effects of preheating treatment of beef patties using a microwave prior to frying at $220^{\circ}C$ for 10 min on each side on the reduction of HCAs (amino-carbolines and amino-imidazo-azaarenes) were evaluated. The amount of HCAs was then evaluated by solid-phase extraction and high pressure liquid chromatography (HPLC) analysis. The beef patties were treated by microwaving for various times (0, 1, 1.5, 2, or 3 min) before pan-frying. The results revealed the presence of 3-amino-1-methyl-5H-pyrido[4,3-b]indole (Trp-P-2), 3-amino-1,4-dimethyl-5H-pyrido-[4,3-b] indole (Trp-P-1), 2-amino-6-methyldipyrido[1,2-a:3',2'-d]imidazole (Glu-P-1), 2-aminodipyrido[1,2-a:3',2'-d]imidazole (Glu-P-2), 9H-pyrido[3,4-b]indole (Norharman), 1-methyl-9H-pyrido[3,4-b]indole (Harman), 2-amino-9H-pyrido[2,3-b] indole ($A{\alpha}C$), 2-amino-3,8 dimethylimidazo[4,5-f]-quinoxaline (MeIQx) and 2-amino-1-methyl-6-phenylimidazo[4,5-b]-pyridine (PhIP) in all samples. However, microwave pretreatment for 1 min inhibited the formation of these HCAs by up to 90% when compared to the control.

• Progress in Superconductivity
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• v.9 no.2
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• pp.127-135
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• 2008

We study the effects of phonon interaction on the superconducting pairing in the high $T_c$ superconductors (HTSC). Using coupled BCS gap equations, we found that phonon interaction can induce a s-wave component to the d-wave gap, mediated by Antiferromagnetic (AFM) spin fluctuations, in the (D+iS) form. However, $T_c$ is not enhanced compared to the pure d-wave pairing without phonon interaction. On the other hand, anisotropic phonon interaction can dramatically enhance the d-wave pairing and $T_c$ itself, together with the AFM spin fluctuation interaction. This ($D_{AFM}+D_{ph}$) type pairing exhibits strongly reduced isotope coefficient despite the large enhancement of $T_c$ by phonon interaction.

• Journal of Photoscience
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• v.8 no.2
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• pp.43-53
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• 2001

a, a parameter that describes how effectively photoinactivated PS II units protect their functional neighbours; car, carotenoids; ΔpH, transthylakoid pH difference; D1 protein, psbA gene product in the PS II reaction centre; f, functional fraction of PS II: F$\_$v//F$\_$m/, the ratio of variable to maximum chlorophyll a fluorescence; k$\_$d/, rate coefficient for degradation of D1 protein; k$\_$i/ and k$\_$r/, rate coefficient for photoinactivation and repair of PS II, respectively; NADP+, oxidized nicontinamide adenine dinucleotide phosphate; P680, the primary electron donor in the PSII reaction centre; Ph, pheophytin; PS, photosystem; Q$\_$A/, first quinone acceptor of an electron in PS II; R$\_$s/, the gross rate of D1 protein synthesis.