• 한국미생물·생명공학회지
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• 제17권2호
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• pp.126-130
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• 1989

인삼 saponin 중에서 조성 비율이 가장 큰 ginsenoside R $b_1$을 약효면에서 훨씬 우수한 ginsenoside-Rd로 선택적 전환할 수 있는 전환효소를 Rhizopus japonicus 배양물로부터 순수하게 정제한 후 그 효소학적 특성을 조사하였다. 본 효소는 pH 4.8~5.0, 45$^{\circ}C$에서 그 활성도가 가장 높았으며 pH4~9의 범위에서 안정하였고, pH5.0에서 6$0^{\circ}C$ 열처리할 경우 50% 실활하는데 2시간이 소요되었다. M $n^{++}$, F $e^{++}$에 의해 효소활성이 촉진되었으며 C $u^{++}$, A $g^+$에 의해서는 저해되었다. 효소 저해제중에는 EDTA, o-phenanthroline 등에 의해 저해되기도 했다. 본 효소는 당류중에는 gentiobiose, cellulose만을, glycoside 중에서는 amygdalin, purnasin, salicin 등을 분해할 수 있었으며 ginsenoside R $b_1$, 이외의 다른 ginsenoside는 전혀 분해할 수 없었다. 본 효소의 Km치는 total saponin 기질 및 ginsenoside Rb group saponin 기질은 ginsenoside R $b_1$으로서 5.0mM 이었으며, gentiobiose는 4.8mM, amygdalin은 3.7mM 이었다.

• Bulletin of the Korean Chemical Society
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• 제23권6호
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• pp.845-851
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• 2002

The synthesis of the intramolecular donor - stabilized silyl and germyl complexes of the type ($Cab^c.p) MMe_2X$ (2a:M=Si, X=Cl;2b;M= Ge, X=Cl;2e;M=Si,X=H) was achieved by the reaction of $LiCab^c,p$ (1) with $Me_2SiClX$ and $Me_2GeCl_2$ respectively. The intramolecular M←P interacion in 2a-2c is provided by $^1H$, $13^C.$, $31^P$ and $29^Si$ NMR spectroscopy. The salt elimination reactions of dichlorotetramethyldisilane and -digermane with 1 afforded the $bis(\sigma-carboranylphosphino)disilane$ and disgermane [$(Cab^C.P)MMe_2]_2(4a;M$ = Si;4b: M=Ge). The oxidative addition reaction of 4a-4b with $pd_2(dba)_3CHCl_3afforded$ the bis(silyl)-and bis(germyl)-palladium complexes. The chloro-bridged dipalladium complexes were obtained by the reaction of 2a-2b with $pd_2(dba)_3CHCl_3$ The crystal structures of 5a and 7b were determined by X-ray structural studies.

• 한국산학기술학회논문지
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• 제16권9호
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• pp.6269-6273
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• 2015

Alamouti 알고리즘에 기반한 M-ary $2{\times}N$ OSTBC(Orthogonal Space Time Block Coded) MIMO(Multi Input Multi Output) 시스템의 성능을 두개의 파라미터, 즉 constellation 숫자(M)와 수신안테나 숫자(N)를 변화시키며 컴퓨터 모의실험에 의하여 알아보았다. $2{\times}N$ MIMO 스템의 성능과 단일 송신안테나 시스템의 성능비교를 위하여 MRC(Maximum Ratio Combining) 다이버시티 안테나 시스템의 성능 역시 컴퓨터 모의실험을 통하여 수행하였다. 10 dB EbNo QPSK 시스템의 경우 Alamouti $2{\times}1$ MIMO가 단수안테나 시스템에 비해 4.2 dB의 BER을 향상시켰으며 $2{\times}2$ MIMO는 $1{\times}2$ MRC 대비 7.4 dB의 BER을 향상시켰다.

• 대한한방내과학회지
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• 제22권3호
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• pp.405-413
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• 2001

Objective: Experimental studies were done to research the effects of Jahap-san(zige-san) on the allergic reaction Methods: For measuring the response about the antiallergic effect we investigated cytokines m-RNA expression of murine splenic B cell, production in anti-CD40 mAb-stimulated murine splenic B cells and the histamine release in IC-2 cells by anti-CD40 mAb-stimulated murine splenic B cells. Results: The extract of Jahap-san(zige-san) revealed significant decrease effect on cytokines m-RNA expression of murine splenic B cell, production in anti-CD40 mAb-stimulated murine splenic B cells and the histamine release in IC-2 cells by anti-CD40 mAb-stimulated murine splenic B cells. Conculusion : The extract of Jahap-san(zige-san) revealed significant effect on the antiallergy.

• 아시안잔디학회지
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• 제18권4호
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• pp.221-229
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• 2004

경북지방에서 분리한 곤충병원성곰팡이 Beauveria bassiana와 Metarhizium anisopliae를 이용하여 나비목 해충인 거세미나방 (Agrotis segetum), 배추흰나비 (Artogeia rapae), 도둑나방 (Mamestra brassicae), 배추좀나방(Plutella xylostella), 파밤나방 (Spodoptera exigua), 담배거세미나방 (S. litura)의 생물적 방제 가능성을 알아보기 위하여 실험한 결과, 거세미나방 2$\cdot$3령충에 대하여 B. bassiana와 M. anisopliae의 반수치사농도 ($LC_50$)는 접종7일 후에 각각 $4.3\times10^6\;conidia/m\ell$와 $2.4\times10^5\;conidia/m\ell$였다. 배추흰나비 2$\cdot$3령충에 대한 B. bassiana와 M. anisopliae의 $LC_50$는 접종 7일 후에 각각 $1.2\times10^7\;conidia/m\ell$와 $5.2\times10^6\;conidia/m\ell$였다. 도둑나방 2$\cdot$3령충에 대한 B. bassiana와 M. anisopliae의 $LC_50$는 접종 7일 후에 각각 $1.5\times10^6\;conidia/m\ell$와 $9.7\times10^5\;conidia/m\ell$였고, 배추좀나방 2$\cdot$3령충에 대한 B. bassiana와 M. anisopliae의 $LC_50$는 각각 $3.0\times10^6\;conidia/m\ell$와 $1.4\times10^6\;conidia/m\ell$였다. 파밤나방 2$\cdot$3령충에 대한 B. bassiana와 M. anisopliae의 $LC_50$는 접종 7일 후에 각각 $6.3\times10^6\;conidia/m\ell$와 $2.6\times10^6\;conidia/m\ell$였고, 담배거세미나방 2$\cdot$3령충에 대한 B. bassiana와 M. anisopliae의 $LC_50$는 각각 $1.6\times10^7\;conidia/m\ell$와 $3.4\times10^6\;conidia/m\ell$였다.

• 한국임상수의학회지
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• 제12권1호
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• pp.789-798
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• 1995

우백혈병 바이러스감염 B 세포주(BL2M3 및 BL312)의 배양상층액에 대한 자기세포들의 증식반응을 검토하였다. 그 결과 BL2M3 및 BL312세포의 배양상층액을 자기세포인 BL2M3세포에 첨가했을 때 농도에 비례하여 현저한 증식을 유도하였다. 이것은 배양 4-5일차, 배양상층액의 첨가농도는 50-60%,세포수는 5x$10^4$-5x$10^{5}$ /ml에서 최적의 증식반응을 보였다. 우태아혈청(FBS) 무첨가 BL2M3 및 BL312세포의 배양상층액에 대해서도 BL2M3세포는 동일한 증식반응을 보였다. 한편 BL2M3 및 BL312세포의 배양상층액을 BL312세포에 첨가했을 때는 BL2M3세포의 경우에 비해 현저하지 않았다. 또한 BL2M3 및 BL312세포의 배양상층액은 말초혈액 림프구에 대해서도 pokeweed mitogen(PWM)첨가 유무에 관계없이 증식을 유도하였다. 그러나 PWM자극 말초혈액 단핵세포의 배양상층액은 BL2M3 및 BL312세포에 대해서 전혀 증식을 유도하지 못했다. 이상의 결과로부터 우백혈병 바이러스감염 B세포주 특히 BL2M3세포는 세포자신이 증식인자를 분비하고 그것과 반응하여 증식하는 소위 autocrine growth 양상을 보이는 것으로 판명되었다.

• Journal of the korean society of oceanography
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• 제34권3호
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• pp.151-166
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• 1999

Both benthic and planktonic foraminifera from Core 97-02 obtained in the northern East China Sea are quantitatively analyzed for reconstructing the paleocenography of late Quaternary. Since the earliest time of the core sediment (last not older than 18000 yr B.P.), the paleo-water depth has changed from less than 20 m to near 100 m at present, which is reflected by the benthic foraminiferal assemblages: before 14000 yr B.P., the water depth was shallower than 20 m; from 14000 to 7500 yr B.P., water depth was 20-50 m; and after 7500 yr B.P., water depth was 50-100 m. The foraminiferal fauna also disclose the water mass history: during the last glacial maximum, the water that dominated the study area might be the coastal water; at the end of the last glacial maximum(14000-9500 yr B.P.), the Yellow Sea Cold Water mostly affected this area; then it gave way to the Yellow Sea Warm Current after 9500 yr B.P.; and finally, the warm water has dominated this area since 9500 yr B.P. because of the westward shift and enhancement of the Kuroshio Current.

• 한국CDE학회논문집
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• 제11권4호
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• pp.246-255
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• 2006

Ribs and fans are interesting geometric entities that are derived from an ordinary $B\'{e}zier$ curve or surface. A rib itself is a $B\'{e}zier$ curve or surface with a lower degree than the given curve or surface. A fan is a vector field whose degree is also lower than its origin. First, we present methods to transform the control points of a $B\'{e}zier$ curve or surface into the control points and vectors of its ribs and fans. Then, we show that a $B\'{e}zier$ curve of degree n is decomposed into a rib of degree (n-1), a fan of degree (n-2), and a scalar function of degree 2. We also show that a $B\'{e}zier$ surface of degree (m, n) is decomposed into a rib of degree (m-1, n-1) and three fans of degrees (m-1, n-2), (m-2, n-1), and (m-2, n-2), respectively. In addition, the lengths of the fans are further controlled by scalar functions of degree 2 and (2, 2). We present relevant notations and definitions, introduce theories, and present some of design examples.

• Bulletin of the Korean Chemical Society
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• 제18권3호
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• pp.318-323
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• 1997

ο-(2-Vinyloxyethoxy)benzylidenemalononitrile (3a) and methyl ο-(2-vinyloxyethoxy)-benzylidenecyanoacetate (3b), m-(2-vinyloxyethoxy)benzylidenemalononitrile (4a), and methyl m-(2-vinyloxyethoxy)benzylidenecyanoacetate (4b) were prepared by the condensation of ο-(2-vinyloxyethoxy)benzaldehyde (1) and m-(2-vinyloxyethoxy)benzaldehyde (2) with malononitrile or methyl cyanoacetate, respectively. Bifunctional vinyl ether monomers 3a and 3b polymerized quantitatively with radical initiators in γ-butyrolactone solution at 65 ℃, while meta-isomers 4a and 4b gave lower yields of polymers under the same conditions. The polymers 5-6 obtained from the monomers 3-4 were insoluble in common solvents due to cross-linking. Under the same polymerization conditions ethyl vinyl ether polymerized well with model compounds ο-methoxybenzylidenemalononitrile 7a, methyl ο-methoxybenzylidenecyanoacetate 7b, m-methoxybenzylidenemalononitrile 8a, and methyl m-methoxybenzylidenecyanoacetate 8b, respectively, to give 1:1 alternating copolymers 9-10 in high yields. Cross-linked polymers 5-6 showed a thermal stability up to 300 ℃, and showed a double phase degradation pattern in their TGA thermograms. Polymers 5-6 showed broad endothermic bands around 75-110 ℃ without any characteristic Tg peaks in DSC thermograms. Alternating copolymers 9-10, except copolymer 9b were soluble in common organic solvents. The inherent viscosities of polymer 9-10 were in the range of 0.35-0.62 dL/g. Polymer films cast from acetone solution were cloudy and tough and Tg values obtained from DSC thermograms were in the range of 118-165 ℃.

• Bulletin of the Korean Chemical Society
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• 제25권7호
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• pp.1012-1019
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• 2004

The synthesis of novel group 9 metal complexes containing the S,S'-chelate ligands, $Li_2S_2C_2B_{10}H_{10}$ (2a) and $LiS(S=PMe_2)C_2B_{10}H_{10$} (2b), is described. Two new dinuclear complexes of the type $[{(cod)M}_2(S,S'-S_2C_2B_{10}H_{10})]$ (cod = 1,5-cyclooctadiene; M = Rh (3a), or Ir (3b)) were synthesized by the reaction of chloridebridged dimers $[M({\mu}-Cl)(cod)]_2$ with one molar equivalent of the corresponding dilithium dithiolato ligand $Li_2S_2C_2B_{10}H_{10}$ (2a). X-ray crystal structure analysis of 3a revealed a dinuclear structure in which each (cod)Rh unit is attached to a distinct sulfur atom of a 1,2-dithio-o-carboranyl ligand (2a). Additionally, the electrochemical properties of 3a and 3b were investigated by cyclic voltammetry. In an analogous manner, reaction of the lithium dithiolato ligand $LiS(S=PMe_2)C_2B_{10}H_{10}$ (2b) with $Cp^{\ast}CoI_2(CO)$ produced a mononuclear dithiolato complex, $[Cp^{\ast}CoI{(S,S'-S(S=PMe_2)C_2B_{10}H_{10})}]$ (4), which was characterized by single-crystal X-ray analysis.