• Macromolecular Research
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• 제14권6호
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• pp.634-639
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• 2006

Waterborne polyurethane (WBPU) adhesive with varying amounts of dimethylol propionic acid (DMPA) was synthesized by prepolymer process and blended with polyisocyanate hardener. The mean particle size of the WBPU dispersion decreased with increasing DMPA content. $^1H$ NMR spectroscopy confirmed the formation of allophanate bonds and biuret bonds due to the reaction of hardener NCO with urethane/urea groups. The optimum NCO content with the greatest adhesive strength was dependent on the total content of urethane/urea groups in the WBPU molecules. The optimum NCO content increased with increasing number of urethane groups (DMPA content). The adhesion strength of WBPU adhesives was maximized at a molar ratio of hardener NCO to urethane/urea of about 0.28.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1998년도 Proceedings of UNESCO-internetwork Cooperative Regional Seminar and Workshop on Bioassay Guided Isolation of Bioactive Substances from Natural Products and Microbial Products
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• pp.133-133
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• 1998

Tylopeptins A and B are novel peptides from methanol extract of fruit body of mushroom, Tylopilus neofelleus, These novel peptides were isolated by reverse-phase HPLC. And they have been shown to consist of one acetylated N -terminal residue, fourteen amino acids, and leucinol, C-terminal amino alcohol. Sequencial determination and complete 1H and 13C resonance assignments were based on positive ion F AB mass spectroscopy and two dimensional NMR techniques using HOHAHA, ROSEY, HMQC, and HMBC. These compounds are active against some Gram-positive bacteria, but inactive against phathogenic fungi and Gram-negative bacteria.

• Journal of the Korean Wood Science and Technology
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• 제14권3호
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• pp.30-35
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• 1986

To elucidate chemical structure of the wood extracitives, softwood Larix leplolepis Gorden) metal was extracted with 95% ethanol at room temperature for 72 hours. The extract was fractionated with organic solvents such as n-hexane, chloroform. ether, and ethylacetate. From the n-hexane soluble fraction of the extratives, flavonoid and sterol compounds were isolated and identified as taxifolin(5,7,3',4'-tetrahydroxyflavanonol)(I) and ${\beta}$-sitosterol(II) by UV, IR, $^1$H-NMR spectroscopy and Mass spectrometry.

• 공업화학
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• 제9권4호
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• pp.603-607
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• 1998

Cellulose를 출발물질로 하여 ethylene oxide와 hydroxyethylcellulose를 합성하였다. Epichlorohydrin과 triakylamine을 치환반응시켜 제4급 암모늄염을 만든후, 산을 첨가하여 3-chloro-2-hydroxypropyltrialkylammonium chloride를 얻었다. Hydroxyethylcellulose와 glycidylalkylammonium chloride 또는 3-chloro-2-hydroxypropyltrialkylammonium chloride를 coupling하여 지금까지 알려져 있지 않은 화합물 hydroxyethylcellulose-2-hydroxypropylammonium chloride ether와 hydroxyethyl-cellulose-2-hydroxypropyltriethylammonium chloride ether를 각각 73.9%, 74.2%의 수율로 합성하였다.

• 한국전기전자재료학회논문지
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• 제24권5호
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• pp.398-403
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• 2011

Recently, Near-infrared (NIR)colorant is intriguing and attractive but full of challenges. Although some cyanine colorant have been commercialized, near-infrared colorant with intensive NIR absorption, good chemical and photo-stability, and high solubility still remain as target compound. Certain polycyclic aromatic compounds such as quaterrylene represent a key class of NIR colorant and also give rise to outstanding physical and chemical properties after appropriate chemical modification. In this study, We have tried to introduceimide functional group to quaterrylene in order to give chemical and thermal stability. Finally, N,N'-bis (2,6-diisopropylphenyl)-quarterrylene-3,4:13,14-tetracarboximide was synthesized and evaluated its properties using $^1H$ NMR, Maldi-tof, TGA, and UV/VIS/NIR spectroscopy as NIR colorant. The quaterrylene bisimide compound exhibit a excellent thermal stability and chemical stability.

• Elastomers and Composites
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• 제51권2호
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• pp.99-105
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• 2016

Alkoxy modified silicone (PAMS) was synthesized from hydroxyl-terminated polydimethylsiloxane (OH-PDMS) and vinyltrimethoxysilane (VTMO) under alkali catalyst (NaOH and KOH) at room temperature ($25^{\circ}C$) via condensation polymerization. Then, the structural verification of the synthesized PAMS was confirmed using $^1H$-NMR and FT-IR spectroscopy. The reaction rate of PAMSs was studied in terms of the concentration variation of alkali catalyst. The reaction rate increased with the concentration of alkali catalyst, but no correlation between conversion and concentration of alkali catalyst was observed.

• 통합자연과학논문집
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• 제2권3호
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• pp.190-193
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• 2009

Bis(silyl)palladinum(II) and -platinum(II) complexes are key intermediates for the synthesis of organic silyllated compounds by the Pd or Pt-catalyzed reactions. Reactions of dialkylpalladinum and -platinum complexes with diphenylsilane gave the bis(silyl)palladinum and -platinum complexe in moderate to good yields. Isolated complexes were characterized by $^1H$, $^{13}C$ and $^{31}P$-NMR spectroscopy and elemental analyses. Some of the complexes were determined by X-ray crystallographic studies.

• Bulletin of the Korean Chemical Society
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• 제24권9호
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• pp.1303-1307
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• 2003

The low molecular water-soluble chitosan nanoparticles (LMWSC-NPs) were prepared, which was modified with hydrophilic and hydrophobic moieties to evaluate the potential for pharmaceutics application. The synthesis of LMWSC-NPs was identified by FT-IR and $^1H$-NMR spectra. Also, we measured the photon correlation spectroscopy (PCS), transmission electron microscope (TEM) and atomic force microscope (AFM) to investigate the characteristics and morphology of the LMWSC-NPs. At the PCS measurement, the more increase the number of substitutive group, the more decrease the positive charge of LMWSC-NP surface. From the results of TEM and AFM, spherical morphologies were observed, and their sizes were 30-150 nm. Resultantly, LMWSC-NPs prepared in this experiment will be expected as a suitable device for the drug targeting system.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권1호
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• pp.553-555
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• 2007

Six azomethine polymers containing bent-core mesogen were synthesized with variation of a bent structure of central core (1,2-dioxyphenylene or 2,3-dioxynaphthylene), and a lateral halogen substituent (X = H, F or Cl ). The properties of the polymers were characterized by FT-IR, NMR spectroscopy, DSC, polarizing optical microscopy, and X-ray diffractometry.

• Macromolecular Research
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• 제14권3호
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• pp.387-393
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• 2006

Nanoparticles of Poly(L-glutamic acid) (PG) conjugated to the anticancer drug paclitaxel and targeted moiety folic acid (FA) were synthesized and characterized in vitro. The nanoparticles were designed to take advantage of FA targeting to folate receptor (FR) positive cancer cells. The chemical composition of the conjugate was characterized by $^1H-NMR$, FTIR and UV/vis spectroscopy. The selective cytotoxicity of the FA-PG-paclitaxel conjugates was evaluated in FR positive cancer cells. The interaction of the conjugate was visualized by fluorescence microscopy with results confirming the successful preparation of the conjugate and the production of nanoparticles of about 200-300 nm in diameter. The amount of paclitaxel conjugated to FA-PG was 25% by weight. Cellular uptake of the conjugate was FA dependent, and the conjugate uptake was mediated specifically by the folate receptor. These results demonstrate the improved selective toxicity and effective delivery of an anticancer drug into FR bearing cells in vitro.