• Bulletin of the Korean Chemical Society
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• 제18권3호
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• pp.263-264
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• 1997

• Journal of Photoscience
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• 제10권2호
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• pp.181-184
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• 2003

Photochemical reactions of some organic molecules on titanium dioxide were investigated in methanol. A methanolic solution of trans-cinnamic acid and titanium dioxide was irradiated with 300 nm UV lamps for 24 h to afford methyl cinnamate. In the case of trans-cinnamamide, the major product was found to be 3-phenylpropionamide, i.e., a saturation product of ethylenic double bond. However, irradiation of urocanic acid, caffeic acid, ethyl cinnamate, trans-chalcone, trans-cinnamonitrile, trans-stilbene or trans, trans-1,4-diphenyl-1,3-butadiene on titanium dioxide under the same conditions did not give any noticeable products. Meanwhile, when irradiated some aromatic aldehydes, such as trans-cinnamaldehyde, l-naphthaldehyde, and 2-naphthaldehyde in methanol, vicinal diols and alcohols derived from the diols were produced. On the other hand, irradiation of 9-anthraldehyde and titanium dioxide in methanol afforded only alcohols, in which diol was not observed.

• Bulletin of the Korean Chemical Society
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• 제26권9호
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• pp.1434-1436
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• 2005

• Bulletin of the Korean Chemical Society
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• 제11권1호
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• pp.45-49
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• 1990

${\alpha},{\omega}$-Diols react with secondary amines in the presence of a catalytic amount of ruthenium catalyst at $180^{\circ}C$ to give diamino compounds in good to excellent yields. The yield of diamino compound was affected by the molar ratio of ${\alpha},{\omega}$-diol to secondary amine. The reaction is affected by the nature of the phosphorus ligands employed and the effectiveness of the added ligand is completely different depending on the chain length of the ${\alpha},{\omega}$-diol. The reaction between ethylene glycol and primary amine in the presence of a catalytic amount of ruthenium catalyst gave 1,4-disubstituted piperazine.

• Bulletin of the Korean Chemical Society
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• 제19권6호
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• pp.680-685
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• 1998

Two kinds of new aliphatic diols were synthesized by the ring-opening reaction of lactide and glycolide with 1,4-butanediol, a difunctional initiator, in the presence of stannous octoate. The resulting aliphatic diols were melt-polymerized with D-tartaric acid at 150 ℃ to produce new crosslinkable polyesters. They were reacted with hexamethylene diisocyanate in THF at 65 ℃ in a teflon mold for 24 h to prepare sequentially ordered crosslinked polyesters (BD/LT/GL/D-tartarate). Degradation of the prepared yellow crosslinked films was carried out in a buffer solution in order to examine the effect of time, pH, temperature and crosslinking degree on their degradation rate and mechanism. The rate of degradation increased with an increase in pH and temperature, but it decreased with increasing degree of crosslinkage incorporated into the crosslinked polyesters. We also found that the crosslinked polymers were converted into the acidic compounds such as lactic, glycolic, and D-tartaric acids during the degradation.

• Bulletin of the Korean Chemical Society
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• 제6권6호
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• pp.378-378
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• 1985

• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.1
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• pp.182.2-182.2
• /
• 2002

• 대한약학회:학술대회논문집
• /
• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.1
• /
• pp.184.1-184.1
• /
• 2002

• Fibers and Polymers
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• 제2권3호
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• pp.122-128
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• 2001

UV-curable polyurethane acrylate prepolymers were prepared from diisocyanates [isophorone diisocyanate (IPDI), 2,4-toluene diisocyanate (TDI), or 4,4'-dicyclohexylmethane diisocyanate (H$_{12}$MDI)], diols [ethylene glycol (EG), 1,4-butane diol (BD), or 1,6-hexane diol (HD)], polypropylene glycol as a polyol. UY-curable mixtures were formulated from the prepolymer (90 wt%), reactive diluent monomer trimethylol propane triacrylate (10 wt%). and photoinitiator 1-hydroxycy-clohexyl ketone (3 wt% based on prepolymer/diluent). The effects of different diisocyanates/low molecular weigh dial on the dynamic mechanical thermal properties and elastic recovery of UV-cured polyurethane acrylate films were examined. The tensile storage modulus increased a little in the order of EG > BD > HD at the same diisocyanate. Two loss modulus peaks for all samples are observed owing to the glads transition of softs segments ($T_gh$) and the glass transition temperature of hard segments ($T_gh$). For the same diisocyanate, $T_gh$, decreased, however, $T_gh$ increased, in the order of HD > BD > EG. The elastic recovery also increased in the order of HD > BD > EG at the same diisocyanate. In case of same diols, $T_gh$ increased in the order of $H_12$MDl > TDI > IPDI significantly. The ultimate elongation and elastic recovery increased in the order of TDI > IPDI > $H_12$MDl at the same diol.l.

• 한국작물학회지
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• 제41권6호
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• pp.692-697
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• 1996

담배의 생육단계 및 환경조건에 따른 duva-trlenediols와 cis-abienol의 함량을 조사하였던 바 얻어진 결과는 다음과 같다. 1. 담배생육 단계별 duvatrlenediols와 cis-abienol의 함량은 이식묘일 때 매우 낮았고 이식후 40일 후부터 많은 양이 생성되었다. 2. 담배생육 환경조건에 따른 duvatrienediols와 cis-abienol의 함량은 3$0^{\circ}C$ 인공광실이 가장 높았고 그 다음은 $25^{\circ}C$ 인공광실과 자연광실 그리고 18$^{\circ}C$ 인공광실은 매우 낮았다. 3. 자연광실에 재배된 연초는 도장에서 담배된 담배보다 duvatrienediols와 cis-abienol의 함량 이 높았다. 4. 개화기 때 엽위별 duvatrienediols와 cis-abienot의 함량은 하위엽이 가장 낮았고 중위엽과 상위엽은 비슷하였다. 5. 강우 전에 채취한 시료는 강우 후 즉시 채취한 시료 보다 duvatrienediols와 cis-abienol의 함양이 현저히 높았다.