• Title/Summary/Keyword: 축합

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Synthesis and Properties of PET-PCT Copolyester I - Thermal Property and Degradation Behavior - (PET-PCT 공중합체의 합성과 물성 I - 열적성질과 분해거동 -)

  • 이원옥;김해영;백두현
    • Proceedings of the Korean Fiber Society Conference
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    • 2001.10a
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    • pp.351-354
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    • 2001
  • Poly(ethylene terephthalate) (PET)는 물리적, 기계적 성질이 우수한 엔지니어링 플라스틱의 하나로 섬유, 필름, 및 여러 가지 용도로 다양하게 사용되고 있다. PET는 DMT(dimethyl terephthalate) 또는 TPA(terephthalic acid)와 EG(ethylene glycol)를 축합 중합하여 제조한다. (중략)

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Knoevenagel Reaction in Water Catalyzed by Mesoporous Silica Materials Synthesized from Industrial Waste Coal Fly Ash (석탄회 산업폐기물로부터 제조한 메조다공성 실리카소재를 촉매로 사용하는 Knoevenagel 수용액 반응)

  • Dhokte, Aashish O.;Khillare, Santosh L.;Lande, Machhindra K.;Arbad, Balasaheb R.
    • Journal of the Korean Chemical Society
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    • v.55 no.3
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    • pp.430-435
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    • 2011
  • Coal fly ash of thermal power plants converted into mesoporous materials MCM-41. The synthesized material was characterized by XRD, FT-IR, SEM, and EDS techniques. The catalytic activity of prepared material was studied for the synthesis of 5-arylindene malononitriles via Knoevenagel condensation of aromatic aldehydes and malonontrile is described. The features of present method are easy handling, stability, reusability, and eco-friendliness of catalyst, high yields, short reaction time, simple experimental and work up procedure.

Dry Media Reaction Procedure for Synthesis of α,β-Unsaturated Acids, α-Cyanoacrylonitriles and α-Cyanoacrylates via Knoevenagel Condensation Using NaHSO4·SiO2 Catalyst (NaHSO4·SiO2 촉매를 이용한 Knoevenagel 축합을 거친α,β의 불포화산, α-Cyanoacrylonitriles와 α-Cyanoacrylates의 합성을 위한 무수조건하의 반응 절차)

  • Gopalakrishnan, M.;Sureshkumar, P.;Kanagarajan, V.;Thanusu, J.;Thirunavukkarasu, S.
    • Journal of the Korean Chemical Society
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    • v.51 no.4
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    • pp.346-351
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    • 2007
  • Efficient stereoselective synthesis of α,β-Unsaturated acids, α-Cyanoacrylonitriles and α-Cyanoacrylates has been carried out in the presence of NaHSO4·SiO2 under solvent?free conditions with an E-geometry.

Inhibition Effect against Tyrosinase of Condensed Tannins from Korean Green Tea (한국산 녹차로부터 분리한 축합형 탄닌의 tyrosinase 저해효과)

  • Kim, Jin-Ku;Cha, Woen-Seup;Park, Joon-Hee;Oh, Sang-Lyong;Cho, Young-Je;Chun, Sung-Sook;Choi, Cheong
    • Korean Journal of Food Science and Technology
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    • v.29 no.1
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    • pp.173-177
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    • 1997
  • For the utilizing of tannins in the functional foods and natural inhibitor against browning reaction by tyrosinase in foods, inhibition effect against tyrosinase of tannins from Korean green tea was determined. Acetone extract from Korean green tea showed inhibition effect against tyrosinase. The gallocatechin compounds showed higher inhibition effect than the catechin compounds. In terms of stereo isomers, (-)-epicatechin compounds had higher inhibition effect than the (+)-catechin compounds. The monomer had higher inhibition effect than the dimer.

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Effect of Polyphosphate on Firming Rate of Cooked Rice (축합인산염이 밥의 노화속도에 미치는 영향)

  • Kim, Il-Hwan;Lee, Kyu-Han;Kim, Sung-Kon
    • Korean Journal of Food Science and Technology
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    • v.17 no.4
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    • pp.245-247
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    • 1985
  • The effect of a polyphosphate having $P_2O_5$ content of 67% on the firming rate of nonwaxy (Akibare and Milyang 30) and waxy cooked rice stored at room temperature was investigated. The phosphate retarded the firming rate of Akibare and Milyang 30 by 14.0 and 27:00, respectively. The phosphate reduced the starch components available for crystallization of cooked nonwaxy rice. The phosphate exerted no effect on the firming rate of cooked waxy rice.

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