• 제목/요약/키워드: D6

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낮은 삽입손실을 갖는 새로운 대역통과 필터를 이용한 주파수 3체배기 설계 (Design for Frequency Tripler Using Novel Bandpass Filter with Low Insertion Loss)

  • 민준기;조승용;김현진;김용환;이경학;김대희;윤호석;홍의석
    • 한국통신학회논문지
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    • 제31권10A호
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    • pp.1031-1036
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    • 2006
  • 본 논문은 APDP(Anti-Parallel Diode Pair)를 이용한 3체배기로서 출력단에 기존의 Coupled line BPF가 아닌 낮은 삽입손실과 작은 회로사이즈를 갖는 새로운 구조의 BPF를 제안하였다. 이 제안된 구조의 BPF는 인터디지털 캐패시터와 나선형 개방 스터브로 구성되어 있다. 제안된 BPF만의 삽입손실은 대역$(16.41{\sim}19.23GHz)$내에서 0.7dB이하의 특성을 나타내었다. 3체배기의 변환손실은 기본주파수 $5.72{\sim}6.28GHz$에서 약$16.6{\sim}18.5dB$(평탄도 ${\pm}1dB$)의 특성을 얻었으며 6GHz에서 기본주파수와 5차 고조파 억압특성은 각각 -32.16dBc와 -44.6dBc의 특성을 보였으며, 위상잡음 감쇠특성은 약 9.5dB@100kHz의 특성을 나타내었다.

Staphylococcus aureus 유래 비금속성 이성화효소인 Tagatose-6-phosphate Isomerase의 기질다양성 (Substrate Variety of a Non-metal Dependent Tagatose-6-phosphate Isomerase from Staphylococcus aureus)

  • 오덕근;지은수;권영덕;김혜정;김필
    • 한국미생물·생명공학회지
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    • 제33권2호
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    • pp.106-111
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    • 2005
  • 비금속성 이성화효소로 추정되는 Staphylococcus aureus의 tagatose-6-phosphate isomerase(E.C. 5.3.1.26)의 기질다 양성을 조사하기 위해서 그 구조유전자(lacB;510bp와 lacA;430bp)를 대장균에서 동시발현하였다. 알려진 기질 이외에 D-ribose와 D-allose에 대해 이성화활성이 새롭게 관찰되었다. EDTA 1 mM 존재하에서도 D-ribose와 D-allose에 대하여 각각 EDTA 비존재 조건에 대비하여 $95\%,\;75\%$의 이성화활성을 나타내는 것으로 미루어 tagatose-6-phosphate isomerase가 비금속성 이성화효소임을 밝혔다. 이때 lacA 또는 lacB의 단독발현시에는 이성화활성이 전혀 밝견되지 않았다. D-Ribose와 D-allose에 대한 기질친화상수 ($K_m$)은 각각 26 mM와 142 mM였다.

Acertannin의 화학구조 (The Chemical Structure of Acertannin.)

  • 우린근
    • 약학회지
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    • 제6권1호
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    • pp.11-16
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    • 1962
  • The position of galloyl groups in acertannin, as 3, 6-digalloylpolygalito, has been established by well-defined processes. In the courses of the processes eight new compounds, octamethoxyacertannin, 2, 4-dimethoxy-1, 5-anhydro-D-sorbitol, 6-tosylpolygalito, 2, 3, 4-tri-benzoyl-6-tosylpolygalitol, 3, 6-anhydro-1, 5-anhydro-D-sorbitol, and 2, 4-ditosyl-3, 6-anhydro-1, 5-anhydro-D-sorbitol, have been characterized.

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PLL을 이용한 K-band용 발진기에 관한 연구 (A Study on the PLL oscillator for K-band)

  • 이용덕;장준혁;류근관;이기학;홍의석
    • 한국통신학회논문지
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    • 제25권4A호
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    • pp.586-591
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    • 2000
  • 본 논문에서는 새로운 동조형태 방법을 사용한 위상고정 루프(PLL : Phase Locked Loop)의 궤환 성질을 이용하여 K-band용 위상고정 hair-pin 공진 발진기 (PLHRO)를 설계 및 제작하였다. 24.42GHz 위상고정 Hair-pin 공진 발진기는 반송주파수로부터 100KHz, 10KHz 떨어진 곳에서 각각 -86.6dBc/Hz, -76.5dBc/Hz의 위상잡음 특성을 나타내었고 출력은 -0.6dBm 이었다. 또한 -23dBc이하의 기본 주파수 억압특성과 -65dBc의 스퓨리어스 잡음 특성을 나타내었다. 완충증폭기를 포함한 24.42GHz 위상고정 hair-pin 공진 발진기는 반송주파수로부터 100KHz, 10KHz 떨어진 곳에서 각각 -77.34dBc/Hz, -72dBc/Hz의 위상잡음 특성을 나타내었고 출력은 5.6dBm이었다.

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Phytochemical Constituents of Salsola komarovii and Their Effects on NGF Induction

  • Cho, Hyeon Kyung;Suh, Won Se;Kim, Ki Hyun;Kim, Sun Yeou;Lee, Kang Ro
    • Natural Product Sciences
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    • 제20권2호
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    • pp.95-101
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    • 2014
  • Five lignan glycosides, seven megastigmane glycosides, and seven phenolic compounds were isolated by repeated column chromatography from the MeOH extract of Salsola komarovii. Their structures were determined to be lariciresinol-9-O-${\beta}$-$\small{D}$-glucopyranoside (1), alangilignoside C (2), conicaoside (3), (+)-lyoniresinol 9'-O-${\beta}$-$\small{D}$-glucopyranoside (4), (8S,8'R,7'R)-9'-[(${\beta}$-glucopyranosyl)oxy]lyoniresinol (5), blumenyl B ${\beta}$-$\small{D}$-glucopyranoside (6), blumenyl A ${\beta}$-$\small{D}$-glucopyranoside (7), staphylionoside D (8), icariside $B_2$ (9), (6R,9S)-3-oxo-${\alpha}$-ionol ${\beta}$-$\small{D}$-glucopyranoside (10), 3-oxo-${\alpha}$-ionol 9-O-${\beta}$-$\small{D}$-apiofuranosyl-($1{\rightarrow}6$)-${\beta}$-$\small{D}$-glucopyranoside (11), blumenol B 9-O-${\beta}$-$\small{D}$-apiofuranosyl-($1{\rightarrow}6$)-${\beta}$-$\small{D}$-glucopyranoside (12), benzyl 6-O-${\beta}$-$\small{D}$-apiofuranosyl-${\beta}$-$\small{D}$-glucopyranoside (13), canthoside C (14), tachioside (15), isotachioside (16), biophenol 2 (17), 2-(3,4-dihydroxy)-phenyl-ethyl-${\beta}$-$\small{D}$-glucopyranoside (18), and cuneataside C (19) by spectroscopic methods. All the isolated compounds 1 - 19 were reported from this source for the first time. Compounds 2, 3 and 6 upregulated NGF secretion to $118.8{\pm}3.6%$, $128.2{\pm}9.3%$ and $111.1{\pm}7.1%$ without significant cell toxicity.

공액 이중 결합을 갖는 Adenosine과 Uridine 유사체의 합성 (Synthesis of Adenosine and Uridine Analogues Containing Conjugated Diene)

  • 노봉오
    • 대한화학회지
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    • 제45권4호
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    • pp.312-317
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    • 2001
  • 7'-Aldehyde-nucleoside 유사체(2a, 2c)을 6-N-benzoyl-2',3'-O-isopropylideneadenosiner과 uridine으로부터 합성하였다. 2와 Wittig reagent인 ethoxycarbonylmethylene을 축합시켜 ethoxycarbonyl group을 갖는 탄소수를 증가시킨 공액 이중 결합을 지닌 nucleosi de 유사체, ethyl-1',5',6',7',8'-pentadeoxy-1'-(adenin-9-yl)-$\beta$-D-ribo-nnona-5'(E).7'(E)-dienofuranuronate(4b), ethyl-1',5',6',7',8'-pentadeoxy-1'-(uracyl-1-yl)-$\beta$-D-ribo-nona-5'(E),7'(E)-dienofuranuronate(4c)을 얻었다. 또한 2와 CBr4, Ph3P을 반응시켜 공액 이중 결합을 지닌 9-[8',8'-dibromo-5',6',7',8'-tetradeoxy-$\beta$-D-ribo-octa-5'(E),7'(E)-diene]nucleosides (6b,6c) 유사체를 각각 합성하였다.

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DNA Chip을 이용한 Transcriptional Activation Mechanism 분석

  • 김영준
    • 한국생물정보학회:학술대회논문집
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    • 한국생물정보시스템생물학회 2001년도 제2회 생물정보 워크샵 (DNA Chip Bioinformatics)
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    • pp.45-60
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    • 2001
  • . Mediator of transcriptional regulation is the evolutionary conserved coactivator complex that plays He central role in the integration and recruitment of diverse regulatory signals and transcription machinery to certain promoters. In yeast, each Mediator subunit is required for transcriptional regulation of a distinct group of genes. In order to decipher the mechanistic roles of Mediator proteins in regulating developmental specific gene expression, we isolated, and analyzed a multiprotein complex containing Drosophila Mediate. homologs (dMediato.). dMediato. interacts with several sequence-sperific transcription factors and basal transcription machinery, and is critical for activated transcription in response to diverse transcriptional activators. In order to elucidate the function of Mediator in metazoan development, we isolated mutants of a conserved Mediate. subunit, Drosophila Med6 (dMed6). dMed6 null homozygotes failed to pupate and died in the third larval instar. Larval mitotic cells and most imaginal discs showed severe defects in proliferation, but no apparent morphological defect was observed in other larval tissues. Clonal analysis of dMed6 mutant cells revealed that dMed6 is essential for cell viability and proliferation of most adult cell types. Drosophila cDNA microarray, quantitative RT-PCR, and in situ expression analyses of developmentally regulated genes in dMed6 mutants showed that transcriptional activation of a subset of genes involved in neuroblast proliferation in the larval brain were most affected. Our results suggest that dMed6 is required in most for transcriptional regulation of a subset of genes important for cell proliferation and metabolism.

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액체 레이저의 매질 개발을 목적으로 한 $Nd^{3+}$ 착물의 광학적 특성 (Optical properties of $Nd^{3+}$ complexes for liquid laser material)

  • 김정호
    • 한국광학회지
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    • 제10권4호
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    • pp.318-322
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    • 1999
  • 액체 레이저의 매질 개발을 목적으로 $Nd^{3+}$ 주위에 저진동 모드의 결합으로 배위자를 형성하는 $Nd(HFA-D)_3$ 착물에 있어서의 $Nd^{3+}$ 이온의 발광특성은 유기용매의 종류에 의존하며, 강한 배위능력을 지니고 있는 용매일수록 발광특성이 우수한 결과로부터 액체 레이저 매질의 개발 시 유기용매로서는 $DMSO-d_6$가 유력한 후보임을 제시하였다. $DMSO-d_6$ 용매로 사용한 $Nd(HFA-D)_3$ 착물의 경우, 파장 585nm($^4F_{3/2}$)에 있어서의 흡수단면적은 $0.92{\times}10^{-20}\textrm{cm}^2$, 발광강도는 1.0$\mu\textrm{m}$대($^4F_{3/2}\Rightarrow ^4I_{11/2}$, Peak파장 : 1062nm)에서 가장 강하였으며, 발광스펙트럼의 반치폭 (FHWM)은 31nm, 발광수명은 약 12.0mus, 유도방출 단면적은 $3.89{\times}10_{-20}\textrm{cm}^2$ 였다.

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6-Fluoroquinolone Carboxamidopenicillin 유도체의 합성 (The Synthesis of 6-Fluoroquinolone Carboxamidopenicillin Derivatives)

  • 임철부;김정주
    • 약학회지
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    • 제31권2호
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    • pp.92-97
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    • 1987
  • The N-[1H-6-fluoro-1,4-dihydro-4-oxo-7-chloroquinoline-3-carboxy] succinimide was reacted with amoxicillin, ampicillin and 6-APA to give 6-[D-(-)-$\alpha$-{1H-6-fluoro-1,4-dihydro-4-oxo-7-chloroguinoline-3-carboxamido} p-hydroxyphanyl acetamido] penicillanic acid [1], 6-[D-(-)-$\alpha$-{1H-6-fluoro-1,4-dihydro-4-oxo-7-chloroquinoline-3-carboxamido} phenylacetamido] penicillanic acid [10] and 6-[1H-6-fluoro-1,4-dihydro-4-oxo-7-chloroquinoline-3-carboxamido] penicillanic acid [19]. The 1-alkyl-6-fluoro-1,4-dihydro-4-oxo-7-substituted quinoline-3-carboxylic acids were reacted with ethyl chloroformate for making mixed anhydride; these mixed anhydrides were reacted with amoxicillin, ampilcillin and 6-APA to give 6-[D-(-)-$\alpha$-{1-alkyl-6-fluoro-1,4-dihydro-4-oxo-7-substituted quinoline-3-carboxamido} p-hydroxyphenylacetamido] penicillanic acid [2-9], 6-[D-(1)-$\alpha$-{1-alkyl-6-fluoro-1,4-dihydro-4-oxo-7-substituted quinoline-3-carboxamido} phenylacetamidod penicillanic acid [11-18] and 6-[1-alkyl-6-fluoro-1,4-dihydro-4-oxo-7-substituted quinoline-3-carboxamido] penicillanic acid [20-27].

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떡버들 잎의 플라보노이드 (Flavonoids from Salix hallaisanensis Leaves)

  • 오미현;함인혜;정성희;황완균
    • 생약학회지
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    • 제36권4호통권143호
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    • pp.282-290
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    • 2005
  • The MeOH extract of the the leaves of Salix hallaisanensis (Salicaceae) was partitioned successively with $CHCl_3$, 20% MeOH, 40% MeOH and 60% MeOH solution. From the fractions obtained, 9 compounds were isolated, $diosmetin-7-O-{\beta}-d-glucoside$ (I), $diosmetin-7-O-{\beta}-D-glucosyl-(1{\rightarrow)6)-{\beta}-d-glucoside$ (II), $diosmetin-7-O-{\beta}-d-xylosyl-(1{\rightarrow}6)-{\beta}-D-glucoside$ (III), $quercetin-3-O-{\beta}-d-galactoside$ (hyperoside) (IV), $quercetin-3-O-{\alpha}-l-rhamnosyl-(1{\rightarrow}6)-{\beta}-D-glucoside(rutin)$ (V), luteolin (VI), $luteolin-7-O-{\beta}-d-glucoside$ (VII), $kaempferol-3-O-{\alpha}-l-rhamnosyl-(1{\rightarrow}6)-{\beta}-D-glucoside$ (VIII), and (+)-catechin (IX).