• Title/Summary/Keyword: Chemical product

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Studies on the Synthesis of ${\alpha}$-Ethyl-4,6-Diiodo-W,3-Dehydro-2,3,4,6-Tetradeoxy-D-Glucoside (${\alpha}$-Athyl-4:6-Diiodo-2:3-Dehydro-2:3:4:6-Tetradeoxy-D-Glucosid 의 合成에 關하여)

  • K. C. Kum
    • Journal of the Korean Chemical Society
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    • v.7 no.2
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    • pp.140-143
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    • 1963
  • ${\alpha}$-Ethyl-4,6-diiodo-2,3-dehydro-2,3,4,6-tetradeoxy-D-glucoside was synthesized from glucose through a modified Fischer et al. method. The yield of reduction process of an intermediate triacetylglucal, was markedly increased by utilizing lyophilization technique for removing the water in the reaction product.

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Kinetics of Reversible Consecutive Reactions

  • Park, Tae Jun
    • Bulletin of the Korean Chemical Society
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    • v.34 no.1
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    • pp.243-245
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    • 2013
  • Rate equations are exactly solved for the reversible consecutive reaction of the first-order and the time-dependence of concentrations is analytically determined for species in the reaction. With the assumption of pseudo first-order reaction, the calculation applies and determines the concentration of product accurately and explicitly as a function of time in the unimolecular decomposition of Lindemann and in the enzyme catalysis of Michaelis-Menten whose rate laws have been approximated in terms of reactant concentrations by the steady-state approximation.

Hydrothermal Synthesis of Mesostructured Vanadium Oxide and Application of UV-Ozone Treatment

  • Chang, Ju-Yeon;Jung, Duk-Young
    • Bulletin of the Korean Chemical Society
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    • v.24 no.5
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    • pp.613-616
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    • 2003
  • Effect on hydrothermal treatment of lamellar vanadium oxides was investigated and the formation of hexagonal and cubic mesophase was found. This lamellar materials were prepared by mixing of cetyltrimethylammonium-bromide and pH-controlled sodium metavanadate solution. Thermal method and UV/O₃treatment were applied to extract organic template. The structure of resulting product was studied by powder X-ray diffraction and transmission electron microscopy (TEM).

Development of preventive System for Accident Causing by Human Error in Small Manufacturing Industries of Chemical Products (중소화학제품 제조업의 인적오류 사고예방 시스템 개발)

  • 김두환
    • Journal of the Korean Professional Engineers Association
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    • v.34 no.3
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    • pp.22-27
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    • 2001
  • About 70% -80% of the serious injury that occure in the chemical product small manufacturing industries is caused by human error. but technical development for analysis and inspection to preestimate and exclude such human error is still insufficient. Small - to - medium sited enterprises are economically vulnerable and technical foundations for safety management is week Under such circumstances development of easy to use computerized support programs that can be operated without the help of professioanals are keenly needed.

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Fuzzy Learning Control: Application to an Industrial Polymerization Reactor

  • Seokho-Yi;Park, Sunwon-
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 1993.06a
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    • pp.1106-1108
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    • 1993
  • This paper deals with an industrial application of a fuzzy feedback combined learning control to an industrial batch free radical polymerization reactor. As a result, the plant has reduced the batch reaction time by 50 minute and stabilized both by 40 percent reduction of the standard deviations of product qualities, such as the total solid content and the graft gum, and by 45 percent reduction of the standard deviation of the batch reaction end time.

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Synthesis of Novel 9-Fluoroanthracycline Derivatives

  • Rho, Young S.;박시호;Kim, Sun Y.;조인호;이철현;정채준;Kang, Heun S.
    • Bulletin of the Korean Chemical Society
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    • v.19 no.1
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    • pp.74-78
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    • 1998
  • Synthesis of novel 9-fluoroanthracyclines carrying L-fucose as a sugar component is described. Compound 3 containing a fluorine at the C-9 position was synthesized from an epoxide 2 and HF/Pyr (7 : 3). Bromination and hydrolysis of compound 3 resulted in synthesis of an aglycone, 9-fluoroanthracyclinone 6. The α-(1b) and β -anomers (1a) of the final product were obtained in high yields by a coupling reaction with the L-fucose.

Photoreaction of 8-Methoxypsoralen with Thymine

  • Shim, Sang-Chul;Kim, Yong-Zu
    • Bulletin of the Korean Chemical Society
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    • v.4 no.2
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    • pp.95-99
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    • 1983
  • Photoreaction of 8-methoxypsoralen (8-MOP) with thymine (${\ge}$ 300 nm) was carried out in the dioxane-water frozen state. One major and two minor monoaddition products between 8-MOP and thymine were isolated by various chromatographic methods. Major monoadduct was characterized to be a C4 cycloaddition product formed between 5,6-double bond of thymine and 3,4-double bond of 8-MOP with cis-anti stereochemistry. Two minor adducts were proved to be stereoisomers of this major adduct.

Studies of Porphyrin Synthesis through 3+1 Condensation

  • Lee, Chang Hui;Park, Ju Yeon;Kim, Han Je
    • Bulletin of the Korean Chemical Society
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    • v.21 no.1
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    • pp.97-100
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    • 2000
  • Acid-catalyzed porphyrin formation from meso-aryltripyrromethanes and $25-bis({\alpha}$, - hydroxyl - $\alpha$ -phenyl) methylfuran is studied. The condensation resulted in selective scrambling of tripyrromethanes when the condensation was carried out with catalytic amounts of $BF_3$ in methylene chloride. But the reaction carried out with p-TsOH or $BEt_3$ catalysts in the presence of $NH_4Cl$ in acetonitrile, single porphyrin product was isolated without scrambling of starting tripyrromethane. The yields of porphyrin in these studies were somewhat lower than those of 2+2 condensations or aldehyde-pyrrole condensations.