• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 2002.11a
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• pp.185-186
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• 2002

폐 플라스틱은 석유 물질인 탄화수소로 구성하고 있지만 효과적으로 재활용되지 못하고 대부분 매립, 소각 등의 방법으로 처리하고 있다. 플라스틱은 다양한 용도로 사용되기 때문에 플라스틱의 이용과 소비의 증가는 필연적이다. 예로 미국 가정의 폐 플라스틱은 63% 폴리에틸렌, 11% 폴리프로필렌, 11% 폴리스타이렌, 7% PET 그리고 7% PVC가 발생되는데 이들 화합물 구조가 포화탄화수소형이기 때문에 70% 정도가 방향족 화합물인 석탄에 비해 수소첨가 반응이 요구되지 않는다.(중략)

• The Korean Journal of Pesticide Science
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• v.9 no.3
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• pp.185-190
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• 2005

Solid phase synthesis of 16, which is a derivative of the first systemic fungicide, carboxin 1 was described. Reaction of 1,3-oxathiolane derivative with solid resin of 4-hydroxy-3-nitrobenzophenone 6 gave 9 in 82% yield. Oxidation of sulfur in the solid 1,3-oxathiolane 9 by MCPBA followed by a ring expansion reaction under the acid catalyst afforded the corresponding dihydro-1,4-oxathiin derivative 12. Treatment of the solid 1,3-oxathiolane 9 with p-methoxyaniline resulted in 1,3-oxathiolane 14, 1,3-oxathiolane sulfoxide 15, dihydro-1,4-oxathiin 16, and acetoacetanilide derivative 17 in 41%, 35%, 14%, 10% yields, respectively.

• Korean Chemical Engineering Research
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• v.46 no.4
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• pp.813-818
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• 2008

Various additives were added in small amounts on Ni/YSZ anode of SOFC (solid oxide fuel cell) in order to improve reactivity and to inhibit deactivation due to coke deposition during methane reforming using a low mole ratio steam ($H_2O/CH_4=1.5$) at $800^{\circ}C$. Ni/YSZ catalysts added with various perovskites did not show any improvement but exhibited a gradual decrease in the methane conversion. K-doped Ni/YSZ showed a steady increase and maintenance of the conversion up to 42 hours, after which there was an abrupt deactivation of catalyst owing to potassium loss by volatilization. Addition of 5% of $K_2Ti_2O_5$ on Ni/YSZ showed a stable maintenance of the conversion without K loss, and was able to prevent coke formation during a long time operation. Deactivation of catalyst during the reaction was mainly caused by the accumulation of graphidic carbon on the catalyst surface.

• Korean Chemical Engineering Research
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• v.43 no.5
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• pp.566-570
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• 2005

The study on the hydrogenation and isomerization of unsaturated bicyclic hydrcarbon compounds using methylcyclopentadiene dimer (MCPD) was carried out. Exo compound was prepared through isomerization reaction after two hydrogenation reaction steps. In the first hydrogenation reaction which needs one mole of hydrogen, the formation rate of monomer was increased as dimer was decomposed at reaction temperature above $100^{\circ}C$. At first hydrogenation, DHDMCPD [dihydrodi(methylcyclopentadiene)] was formed and second hydrogenation was proceeded to produce THDMCPD [tetrahydrodi(methylcyclopentadiene)], the ratio of exo to endo THDMCPD was varied by the control of 2nd hydrogenation temperature. To improve the process, continuous 1st and 2nd hydrogenation conditions were established by using the 2nd stage heat controllable reactor. Also, catalytic activities were compared by the use of halogenized aluminum, metal halides and solid acids catalysts on the isomerization reaction from endo to exo THDMCPD.

• Applied Chemistry for Engineering
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• v.9 no.5
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• pp.749-753
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• 1998

Methoxy polyoxyethylene dodecanoates, kinds of nonionic surfactants, could be obtained from addition of ethylene oxide (5, 7, 9, and 12mol) with fatty acid methyl ester utilizing solid catalyst, metal oxide. Because ethylene oxide (EO) couldn't react directly in acid or alkali catalyst with dodecanoic acid methyl ester (DME) that had no active hydrogen, the reaction to add EO was carried out using active solid catalyst. By using IR, HPLC and $^1H$ NMR analysis, structural confirmation of methyl polyoxy ethylene dodecanate showed high yield ranging from 93 to 97%. EO unit mol number of reacted products was 5.2, 7.1, 9.2 and 12.1 mol respectively. Also, EO adduct distrobution of ethoxylated methyl laurate (MPD) had normal distribution curve like polyoxyethylene alkyl ether (AE).

• Korean Journal of Food Science and Technology
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• v.22 no.6
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• pp.681-685
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• 1990

Changes in the physicochemical characteristics and trans acid of cottonseed oil under the condition of selective hydrogenation, temperature$210^{\circ}C,\;H_2\;pressure\;0.3\;kg/cm^2$ Ni catalyst amount 0.12% (in oil), agitation speed 280 rpm, were investigated. The saturated fatty acid such as palmitic acid and stearic acid did not show any difference, while linoleic acid($50.03%{\rightarrow}9.38%$) were transformed to oleic acid ($20.65%{\rightarrow}60.35%$) during hydrogenation. In linoleic acid isomers, cc form were reduced significantly, but ct, tc, tt form showed little change, respectively. In oleic acid isomer, t form increased markedly, whereas there was no significant difference in c form. Meanwhile, melting point(MP) and solid fat content (SFC) were linearly increased, but iodine value(IV) linearly decreased as hydrogenation proceeded. From these results, linear regression equations were obtained as follows. MP & IV : Y= 1.59-2.36X(r=-0.96, p<0.05), SFC($at\;20^{\circ}C$) & MP : Y=2.81+2.01X(r=0.96, p<0.05), SFC($at\;20^{\circ}C$) & IV : Y=9.40-5.16X(r=-0.99, p<0.01), SFC($at\;20^{\circ}C$) & 18 : 1t : Y=6.25+8.48X(r=0.97, p<0.05)

• KSBB Journal
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• v.19 no.4
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• pp.274-283
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• 2004

Six lumbrokinase (LK) fractions from Lumbricus rubellus lysates were purified by a series of column chromatographies. The molecular weights of the six LK fractions appeared to range from 24.6 to 33.1 kDa. In the experimental model of rat venous thrombosis, the thrombus weight and PAI activity decreased significantly when the LK was administered orally. However, the activities of APTT, PT and plasmin showed a significant increase. The aggregation of rat platelets pretreated with various LK doses was inhibited by thrombin, and the MDA generation decreased. The rat thoracic aorta and mesentric arteries contracted with phenylephrine relaxed due to the treatment of the LK fractions. These results suggest that the fibrinolytic effects of LK were mediated not only by proteolytic activity, but also by the inhibition of platelet agregation and the relaxation of blood vessels. It is concluded that the LK may be useful as a hemolytic agent for treatment of fibrin clot.

• Applied Chemistry for Engineering
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• v.25 no.3
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• pp.254-261
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• 2014

The transformer is a static electrical device that transfers energy by inductive coupling. Then, heat is occurred at coils, inner transformer was filled with insulating oils for cooling and insulation. Although mineral oil as insulating oil has been widely used, it does not meet health and current environmental laws because it is not biodegradable. Therefore, in this study, the diglycerol ester was synthesized with diglycerol and fatty acids (oleic acid and caprylic acid) over various catalysts for insulating oil having biodegradability, high flash points and low pour points. The sulfated zirconia ($SO_4{^{2-}}/ZrO_2$) catalyst prepared at different calcination temperature shows the highest conversion of fatty acids at $600^{\circ}C$ due to crystallinity and high density of acid sites per surface area. When the molar ratio of oleic acid and caprylic acid is 1:3, the diglycerol ester shows superior insulation properties that are the flash point of $306^{\circ}C$ and pour point of $-50^{\circ}C$. The insulation properties of synthesized diglycerol ester shows the pour point of $-50^{\circ}C$ and the flash point of over $300^{\circ}C$. Therefore, diglycerol ester is superior to the vegetable oils in insulation properties.

• Applied Chemistry for Engineering
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• v.23 no.3
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• pp.320-325
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• 2012

The catalytic cracking of waste lubricant oil was carried out on silica-alumina (SA), hydrogen-type mordenite (HM), and dealuminated mordenite (DM) with the silica/alumina ratio of 10.5, 10, and 12.5, respectively. Activity in the catalytic cracking was found to be in the order of SA > DM > HM. Carbon number distribution of the oil obtained over SA was similar to that of gasoline while that of the oil obtained over DM was similar to that of diesel. Carbon number distribution of the oil obtained over HM was similar to that between gasoline and diesel. Acid amounts of three kinds of catalysts were found to be in the order of $SA\;{\approx}\;HM$ > DM. Unlike HM and DM with pores of an uniform diameter below 10 A, SA had a pore size distribution within the range of 10 to 50 A. These results indicate that the acid amount and pore size of the catalysts may be related to the carbon number distribution of the cracked oil. The decrement of surface area by the accumulation of carbon and impurities on the surface of the catalyst was found to be in the order of SA > DM > HM.

• Journal of the Korean Chemical Society
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• v.33 no.2
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• pp.177-184
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• 1989

Acidic properties of ZSM-5 zeolite catalysts were investigated by temperature-programmed desorption technique and ir spectroscopy. Ammonia t.p.d. pattern of HZSM-5 showed three different states, designated as ${\alpha}$,${\beta}$ and ${\gamma}$. The amount of ${\gamma}$-state decreased with increasing $SiO_2/Al_2O_3$ ratio, and upon cation-exchanging with alkali cations. From the ir adsorption spectra of absorbed pyridine and the reaction study of toluene alkylation, the ${\gamma}$-state could be explained to be due to the strong Bronsted acid sites of H-ZSM-5. Also they showed that the interaction between alkali cation-exchanged ZSM-5 and bases, i.e. $NH_3$ and pyridine, was increasing with decreasing the size of cations.