• Archives of Pharmacal Research
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• 제12권2호
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• pp.135-137
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• 1989

A convenient route is reported for the synthesis of certain series of 4H-thieno[2,3-b][1]benzothiopyran-4-ones, carrying various substituents at position 2 such as arylazomethines (7,8), thiazolidin-4-ones (9-13), ${\alpha},\;{\beta}-unsaturated$ ketones (16,17), 2-pyridones (19-23), tetrahydrothiophen-4-ones (24,28), and nitroalkenes (29,30), as potential schistosomicidal or antihistaminic agents.

• 전자공학회논문지A
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• 제31A권5호
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• pp.101-105
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• 1994

The EL lamp have been fabricated by screen printing method. the thickness of BaTiO$_3$ dielectric layer and ZnS:Cu phosphor layer was 20 $\mu$m and 40 $\mu$m, respectively. The threshold voltage of green El lamp was 50 $V_{p-p}$ and the maximum brightness was 13.5 $\mu$ W/cm$^2$ at frequency of 700 Hz and the input voltage of 250 $V_{p-p}$. Also when the Rodamin G6 of 0.02 g was doped, the threshold voltage of white EL lamp was 70 $V_{p-p}$ and the maximum brightness was 34 $\mu$W/cm$^2$.

• 이베로아메리카
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• 제13권1호
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• pp.255-286
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• 2011

Las fronteras de México. Guatemala y Belize se formaron cuando se indepedizaron desde España. Generalmente se adaptaron la división establecida durante la época colonial. Sin embargo, se han sucedido varios incidentes para alterarla. Uno de los incidentes más importantes fue 'la Guerra de Castas de Yucatán'. Los mayas aprovecharon esa oportunidad para expresar sus resentimientos que se formaron bajo el sistema colonial. Las rebeliones mayas ocuparon la parte oriente de la península y se formaron un país independiente que se duró más de 50 años. Para apacificar esta gran rebelión de los mayas indígenas, el gobierno mexicano dejó de perder el territorio de Belize que mantenía su soberania durante pasados tres siglos. Finalmente se formaron la frontera con Belize.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 춘계학술대회 논문집 센서 박막재료 반도체재료 기술교육
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• pp.90-93
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• 2002

In the surface pressure-area isotherms of mixed monolayers, mixtures containing as much as 30 mol% of AA form stable condensed monolayer while the monolayer without AA is in the expanded state because PVK take on 3D collapsed. All of the mixed monolayers with 0, 10, 20 and 30 mol% of AA could be readily transferred onto ITO substrate at 16, 17, 24 and 26 mN/m, respectively. The monolayer containing 30 mol% of AA, however, showed a roughness value of 28A and became homogeneous decreasing with the phase separation. We fabricated organic EL device of ITO/CuPc/MEL/BBOT/iLiF/Al using mixed monolayer of 13, 19 and 25 layer deposited by LB method as a emitting layer. In the voltage-current characteristics of EL device, current density was much smaller than that of the spin-coated devices. It may due to the large contact resistance existed at the interface of LB layer/organic layer inhibit carrier injection to the emitting layer. EL spectra of device showed peaks at 450. 470, 505, 555 and 650 nm and the white light emission indicate the CIE coordinate x=0.306, y=0.353.

• 생명과학회지
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• 제8권5호
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• pp.526-531
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• 1998

In this study, the composition and characteristics of poly-$\beta$-hydroxybutyrate (PHB) biosynthesized by Actinobacillus sp. EL-9 are investigated. PHB produced by Actinobacillus sp. EL-9 was identified as the homopolymer of 3-hydroxy-butyric acid (PHB) by infrared spectroscopy and nuclear magnetic resonance spectroscopy analysis. The melting tem-perature (T$_{m}$), and crystallization temperature(T$_{c}$) of PHB was 169.7$^{\circ}C$ and 69.13$^{\circ}C$, respectively. The viscosity on he basis of Brookfield viscometer was 6.01 ㎗/g. The viscosity-average molecular weight estimated by Mark-Ho-wink-Sakurada equation was 1.08$\times$10$^{6}$ ($\pm$3,000).00).

• Natural Product Sciences
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• 제2권2호
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• pp.106-114
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• 1996

Four polymethoxyfavones were isolated from the leaves of Citrus deliciosa, three of which (nobiletin, 5-O-demethylnobiletin, and tangeritin) are bioactive. The fourth (7,4'-dihydroxy-5,6,8,3'-tetramethoxyflavone) is reported for the first time in the genus Citrus and is a potential chemotaxonomic marker. The structures of these flavones were confirmed by analysing their spectral data and comparison with similar compounds. The previously reported $^{13}C$ NMR assignment of 5-O-demethylnobiletin has been revised on the basis of 2D NMR experiments (HETCOR, COSY, and COLOC). The chemotaxonomic value of the present finding is verified.

• Transactions on Electrical and Electronic Materials
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• 제13권6호
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• pp.317-321
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• 2012

Poly[4,4'(3,3')-biphenylenevinylene-alt-2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylene-vinylene], 4,4'(3,3')-PBPMEH-PPV, and poly[4,4'(3,3')-biphenylenevinylene-alt-N-ethylhexyl-3,6-carbazolevinylene], 4,4'(3,3')-PBPCAR-PPV, of varying effective conjugation lengths, were synthesized by the well-known Wittig condensation polymerization between the appropriate biphenyl diphosphonium salts and dialdehyde monomers such as carbazole or dialkoxyphenyl dialdehyde. The conjugation lengths of the polymers were controlled by biphenyl linkages (4,4' or 3,3'). The resulting polymers were highly soluble in common organic solvents and exhibited good thermal stability up to $300^{\circ}C$. The synthesized polymers showed UV-visible absorbance and photoluminescence (PL) in the ranges of 314-400 nm and 430-507 nm, respectively. Carbazole and 3,3'-biphenyl containing 3,3'-PBPCAR-PPV showed a blue PL peak at 430 nm. A single-layer light-emitting diode was fabricated in a configuration of ITO/polymer/Al. Electroluminescence (EL) emission of 3,3'-PBPCAR-PPV was shown at 455 nm.

• Archives of Pharmacal Research
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• 제13권2호
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• pp.142-146
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• 1990

Reaction of ethyl 4-chloro-2-phenylpyrimidine-4-carboxylate (4) with 5-chloro-2-methylthiophenol or 3-aryl-4-phenyl-1, 2, 4-triazole-5 thiol yielded the corresponding thioethers (5) and (8a, b), respectively. Careful alkaline hydrolysis of (5) yielded the corresponding carboxylic acid (6). Reaction of (4) with p-aminoacetophenone yielded compound (10) which was reacted with certain aromatic aldehyde to afford the$\alpha,\beta$-unsaturated ketones (11a-d). Condensation of (11a-d) with malononitrile or phenylhydrazine yielded the 2-amino-3-cyanopyridines (12a-f) or the 2-pyrazolines (13a, b) respectively. Seven representative compounds were tested for their in vitro antimicrobial activity against some pathogenic micro-organisms, some of them were proved to be active.

• 한국재료학회지
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• 제13권8호
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• pp.514-518
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• 2003

As a fundamental study on organic electroluminescence(EL), blue emitting materials were synthesized and characterized. Individual blue colored hydrazone derivatives were synthesized from the reaction of aldehydes (phthalaldehyde, isophthalaldehyde) with the corresponding amnios (1-methyl -1-phenylhydrazine, 1,1-diphenylhydrazine hydrochloride). Recrystallization of hydrazones from chloroform revealed the melting temperature within $142∼156^{\circ}C$. Photoluminescence(PL) analysis on each hydrazone showed that emission range were blue(458∼478 nm). The structure of obtained hydrazones were elucidated by FT-IR, $^1$H-NMR and C, H, N elemental analyzer.

• E2M - 전기 전자와 첨단 소재
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• 제15권1호
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• pp.13-21
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• 2002