• Bulletin of the Korean Chemical Society
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• v.7 no.2
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• pp.142-145
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• 1986

Vinylation of highly hindered ${\beta}$-acetoxyvinyl mercurials with olefins in acetonitrile at room temperature in the presence of cupric chloride, as a reoxidant for the palladium, and a catalytic amount of $LiPdCl_3$ gave the corresponding conjugated dienes in moderate to good yields. The (E) or (Z) geometry in vinyl mercurials was retained in the vinylated products. The reaction was tolerant of a wide variety of functional groups ($CO_2$R, CN, OR, OAc) on either the vinyl mercurial or olefin compounds.

• Bulletin of the Korean Chemical Society
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• v.4 no.5
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• pp.197-200
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• 1983

The Diels-Alder cycloaddition reactions between dienes and allenic ketones were studied theoretically using CNDO/2 method. It was found that the reaction is a neutral electron demand type with matrix element control and the reactivity, the regio- and stereo-selectivities can be correctly predicted based on interaction energies calculated with the 4-center FMO formalism.

• Macromolecular Research
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• v.10 no.2
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• pp.97-102
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• 2002

The mixtures of non-conjugated dienes, 4-methyl-1,4-hexadiene and 5-methyl-1,4-hexadiene (MHD), were successfully synthesized by the reaction of isoprene with ethylene using Fe(III)-based catalyst in toluene. The conversion was over 96 mol% on the basis of the initial amount of isoprene used. The production yield for MHD was nearly 50 mol%, the other was polyisoprene. The mixtures were successfully copolymerized with ethylene by using zirconium-based metallocenes. The products were characterized by the combinations of gas chromatography, high temperature gel permeation chromatography, $^1$H NMR, $^{13}$ C NMR, high temperature $^1$H NMR, UV/visible spectroscopy, and differential scanning calorimetry. It was found that 5-methyl-1,4-hexadiene was active enough to be incorporated into the copolymer chain but the corresponding isomeric material,4-methyl-1,4-hexadiene, was inactive in metallocene-catalyzed copolymerizations. Specifically, in the zirconocene-catalyzed copolymerizations of ethylene with MHD, ansa-structure catalysts seem to be more efficient than non-bridged type zirconocene. The degree of incorporation of MHD in the resulting copolymers was able to be controlled by the amount of non-conjugated dienes used initially.

• Journal of Nutrition and Health
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• v.34 no.3
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• pp.253-264
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• 2001

This study was carried out to examine a part of the mechanism for the etiology of diabetic complications. Thirty normal and forty streptozotocin(STZ)-induced diabetic rats were used as the animal models. The animals were sacrificed at the time points of 3 days, 1,2,4 and 6 weeks after STZ-injection and a time course changes in the concentrations of thiobarbituric acid-reactive substances(TBARS) in blood, urine, and tissues, along with the levels of conjugated dienes in tissues were measured as indices of in vivo lipid peroxidation. The activities of antioxidant enzymes, catalase, superoxide dismutase, glutathione peroxidase and the levels of blood retinol and alpha-tocopherol were also measured. The diabetic rats maintained a slightly higher plasma TBARS level throughout the experiment. The urinary TBARS level was significantly higher in diabetic group and gradually increased with time. Concentrations of TBARS in liver, heart, and kidney tissues from diabetic animals were higher than those from the normal group. An increase of conjugated dienes was also observed in the all tissues examined. The kidney tissue of diabetic animals revealed more significant lipid peroxidation state than any other organ tissues. The activities of hepatic antioxidant enzymes such as catalase, superoxide dismutase, glutathione peroxidase were higher in diabetic animals compared to the control ones and increased with the duration of diabetes mellitus. The plasma levels of vitamin A and E were loser in diabetic animals than in normal controls throughout the experimental period. The level of vitamin E in diabetic animals was significantly decreased with the duration of the disease. The results of this study suggest that an effective regimen to suppress the adverse changes in lipid peroxidation and antioxidant defense system is required from the early stage of the disease to prevent the development of diabetic complications. (Korean J Nutrition 34(3) : 253∼264, 2001)

• Journal of Life Science
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• v.13 no.3
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• pp.333-342
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• 2003

The pathogenic effort of high glucose, possibly in concert with fatty acids, is mediated to vascular complications of diabetes via increased production of reactive oxygen species(ROS), reactive nitrogen species(RNS), and subsequent oxidative stress. This study was carried out to investigate the suppressive effect of buchu(Allium tuberosum) on oxidative stress in streptozotocin(STZ)-induced diabetes in Sprague Dawley male rats. The effect of buchu supplementation (10%) on lipid peroxidation, and antioxidative defense system in blood and liver was compared among normal rats fed basal diet(normal) and diabetic rats fed basal diet(DM-control) or 10% buchu-supplemented diet(DM-buchu). Diabetes was experimentally induced by the femoral muscle injection of 50 mg STZ per kg of body weight. Animals were sacrificed after 4 wks of experimental diets feeding. The induction of diabetes by STZ elevated the level of lipid peroxidation represented by thiobarbituric acid-reactive substances(TBARS) and conjugated dienes in plasma, LDL, liver, and erythrocytes. 10% buchu-supplemented diet significantly reduced the levels of conjugated dienes in erythrocytes(p<0.05) and lowered TBARS in liver and LDL to the levels of control. Induction of diabetes by STZ elevated Mn-superoxide dismutase(Mn-SOD) activity and lowered activities of glutathionine reductase(GSH-red) and glutathionine peroxidase(GSH-px). Catalase activity was not affected by the induction of diabetes by STZ. However, buchu supplementation to diabetic rats significantly elevated catalase activity(p<0.05) and slightly elevated GSH-px and GSH-red activities in liver. GSH levels of blood and liver were lowered or not changed by induction of diabetes by STZ, respectively, while buchu supplementation to diabetic rats significantly elevated hepatic GSH level (p<0.05). In conclusion, it can be concluded that buchu might be a food source to attenuate oxidative stress in diabetic patients by inhibiting lipid peroxidation, by increasing hepatic GSH level, and by inducing anti-oxidative enzyme systems.

• Journal of the Korean Chemical Society
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• v.23 no.2
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• pp.115-118
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• 1979

The photochemical reactions and spectral properties of 1,1-diphenyl-2-vinylcyclopropane were studied. Upon direct irradiation of the compound at 253.7nm, 1,1-diphenylethylene was formed as a major product along with a small amount of 4,4-diphenylcyclopentene. Sensitized photoreactions showed quite a different phenomena from those of conjugated dienes supporting the spectral results that the cyclopropane ring does not transmit the conjugation in the compound.

• Journal of the Korean Chemical Society
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• v.56 no.1
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• pp.78-81
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• 2012

Aromatic 2,3-diazabuta-1,3-dienes in glacial acetic acid with isothiocyanate in the presence of catalyst $TiCl_4$ at room temperature produced via criss-cross cycloaddition reactions the corresponding perhydro[1,2,4]triazolo[1,2-a][1,2,4] triazole-1,5-dithiones in relatively high yields and short reaction time.

• Journal of Photoscience
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• v.6 no.1
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• pp.7-12
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• 1999

Irradiation of 1 , 4-diphenylbut-1-en-3-yne 1 and some p-quinones in dichloromethane with 300nm UV light yield tow types of adducts, i.e., p-quinomethanes and cyclobutanes, in which the former were produced via the rearrangement of the intially formed spiro-oxetene intermediates. On the other hadn 1 added to o-quinones to give three types of adducts, i.e., 1, 3-dienes, 1, 4-dioxenes, or spiro-oxetanes, in which the former were found to be applied to synthesize phenanthrene derivatives. A methoxy derivative of enyne 39 was synthesized to investigate the type of thephotoaddition to o-quinones, in which 1, 4-dioxenes were obatained.

• Bulletin of the Korean Mathematical Society
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• v.20 no.2
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• pp.111-122
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• 1983

지금까지 H. Aebli, A. Fricke, R.W. Copeland, G. Steiner, E. Wittmann, R.R.Skemp, Z.P. Dienes등에 의해 Piaget이론의 수학교육적 연구가 상당한 정도로 이루어져 왔다. 그러나 Centre International D'epistemologie Genetique를 중심으로 한 집단사고와 방대한 연구결과를 집약한 소위 'Piaget이론'은 타에 그 종례를 찾아볼 수 없는 포괄적인 것인 바, 지금까지 이루어진 Piaget이론의 수학교육적 접근은 Piaget이론의 한정된 부분의 단편적인 응용에 불과하며, Piaget의 발생적 수학인식론 및 심리학의 중심원리와 연구결과를 반영한 보다 철저한 연구가 요망되고 있다. 본 고는 그 이론적 기초에 관한 연구의 일환으로 1969년에 출판된 Psychologie et pedagogie에 실린 'La didactique des mathematiques'와 1972년 ICMI의 제2차 수학교육국제회의에 기고한 논문 'Comments on mathematical education'에 나타난 수학교육에 대한 Piaget자신의 견해를 그의 수학인식론의 분석적 고찰을 통해 양세화하고, 그 실제적 구현방안을 제시해 본 것이다.

• The Journal of Natural Sciences
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• v.5 no.2
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• pp.63-73
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• 1992

There are many methods of obtaining butadiene described in the literature. In the america it is produced largely from petroleum gases, i.e., by catalytic dehydrogenation of butene of butene-butane mixtures. Butadiene can be recovered from the $C_4$ residue of an olefin plant by distilling off a fraction containing most of the butadiene, catalytically hydrogenating the higher acetylenes to olefins and separating the product from other olefins and isobutane by extraction. Also it can be obtained by cracking naphtha and light oil. Among the individual dienes of commercial importance, 1, 3-butadiene is of first importance. It is used primarily for the production of polymers.In the present paper, it was investigated for a effect of the formation and the growth inhibition of popped corn polymer in butadiene extraction unit. As a result of study, inhibitors, $NaNO_2$ and TBC were good effective for inhibition of the formation and growth in popcorn polymer. The rational formula of popcorn polymer obtained was $(C_4H_6)_x$.