• 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 $(C_4H_6)_x$.

• Transactions of the Korean Society of Automotive Engineers
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• v.22 no.2
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• pp.37-43
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• 2014

Exhaust emissions were studied as a function of gasoline olefin composition in two vehicles-MPI and GDi engine equipped vehicles. Three different gasolines were tested which varied in olefin contents-12, 16 and 20 vol%. Exhaust emissions in two vehicles were affected by changes in gasoline olefin composition. Responses to changes in olefins were similar in both vehicles : reducing olefins lowered emissions of NOx and CO. Measured exhaust emissions included total hydrocarbons (THC), oxides of nitrogen (NOx), carbon monooxide(CO), carbon dioxide($CO_2$), formaldehyde, benzene, toluene, xylene, 1,3-butadiene and acetylene.

• Rapid Communication in Photoscience
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• v.4 no.1
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• pp.19-21
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• 2015

Zeolite is an ideal host material for encapsulating nano-size metal catalyst species because of its defined microporous structure, prominent adsorption/condensation properties, high surface area, chemical/thermal stability, and transparency to light. In this study, $TiO_2$ photocatalyst was incorporated in highly hydrophobic Y zeolite and its photocatalytic activity was examined in the photocatalytic oxidation of olefins under UV-light irradiation using molecular oxygen as an oxygen source. $TiO_2$ nanoparticles incorporated in hydrophobic Y zeolite exhibited a markedly enhanced photocatalytic activity compared with bare $TiO_2$ owing to its excellent affinity toward organic moieties, which facilitates the mass transfer of organic substrates and allows them to efficiently access to the neighboring active $TiO_2$ surface.

• Bulletin of the Korean Chemical Society
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• v.30 no.8
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• pp.1832-1834
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• 2009

A simple and safe method has been presented for conversion of olefins into bromohydrins using hydrogen bromide and hydrogen peroxide as bromide source by visible light induced within a very short time to get high yield bromohydrins along with a little mount dibromo-product. In this paper, cyclohexene is firstly carried out as the model substrate and investigated the bromination under HBr/$H_2O_2$ system using 150 W incandescent light irradiated in C$Cl_4$ within short time to get good yield of 2-bromocyclohexanol along with a little mount of 1,2-dibromocyclohexane; then, a series of alkenes are brominated to corresponding bromohydrins using the same protocol.

• Bulletin of the Korean Chemical Society
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• v.30 no.3
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• pp.541-542
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• 2009

• Proceedings of the Membrane Society of Korea Conference
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• 2004.05a
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• pp.195-198
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• 2004

Annually, 60 millions tons of polyolefins including polyethylene and polypropylene, etc. are produced in the world. During the manufacturing process, 1-2wt% of olefin gases of total feedstock remains unreacted and incinerated into air. Because of high cost of olefins and hazardous emission of carbon dioxide and toxic gases in incineration process, it is of important to recover them efficiently.(omitted)

• Bulletin of the Korean Chemical Society
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• v.7 no.5
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• pp.372-376
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• 1986

Substituted 3,4-dihydro-2H-pyrans ($1_{a-e}$) were prepared by (4 + 2) cycloaddition reaction of dimethyl dicyanofumarate with the corresponding electron-rich olefins. The compounds $1_{a-e}$ were ring-open polymerized by cationic initiators to obtain polymers of 1:1 alternating sequence. Polymerizations were carried out with boron trifluoride etherate in methylene chloride at $-78^{\circ}C$. All the polymers obtained were soluble in common solvents and were reprecipitated by pouring its chloroform solution into diethyl ether. All the compounds $1_{a-e}$ were not as reactive as the corresponding pyrans derived from ${\alpha}$ -cyanoacrylate.

• Bulletin of the Korean Chemical Society
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• v.8 no.5
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• pp.376-380
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• 1987

The cyclobutane forming photocycloaddition reaction of 5(E)-styryl-1,3-dimethyluracil with some olefins occurs on the 5,6-double bond of uracil ring rather than the expected central double bond via an intermediate, probably the photochemical Diels-Alder type adduct. This intermediate formed on short term irradiation of 5(E)-styryl-1,3-dimethyluracil and 2,3-dimethyl-2-butene solution is converted into the $C_4$-cycloadduct on the prolonged irradiation. Quantum yield of the intermediate formation is not linear with the concentration of 2,3-dimethyl-2-butene probably due to the secondary reaction accompanied with the complex reaction kinetics. The intermediate is formed from the lowest excited singlet state.

• Bulletin of the Korean Chemical Society
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• v.7 no.6
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• pp.472-477
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• 1986

The reaction of (E)- or (Z)-1-alkenylmercuric chlorides with acrylic acid derivatives in the presence of 10 mol% of lithium trichloropalladate ($LiPdCl_3$) and an equimolar amount of cupric chloride, as a reoxidant for the palladium, in acetonitrile at room temperature gave the corresponding (E,E)- or (E,Z)-2,4-dienoic acid derivatives stereospecifically in moderate to good yields. The reaction of (E)- or (Z)-3-chloromercuripropenoic acid with olefins under the reaction condintion described above similarly gave good yields of (E,E)- or (Z,E)-2,4-dienoic acids stereospecifically. A side reaction, the homocoupling of alkenylmercuric chlorides, could be minimized by employing the condition described above. However, in the reaction of 3-chloromercuripropenoic acid with olefins under the present condition, the homocoupled side reaction product was not produced.

• Bulletin of the Korean Chemical Society
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• v.15 no.12
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• pp.1112-1118
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• 1994

Epoxidation of olefins has been studied using iodosylbenzene (PhIO) as the terminal oxidant and binuclear and mononuclear complexes of $Mn^{2+}$, $Co^{2+}$, and $Cu^{2+}$ as catalysts. Epoxides were the predominant products with trace amounts of allylic oxidation products, and the metal complexes were found to be effective catalysts in the epoxidation reactions. The reactivity of binuclear copper complexes was greater than that of the mononuclear copper complexes, whereas the binuclear and mononuclear complexes of $Mn^{2+}$ and $Co^{2+}$ showed similar reactivities. The nature of the ligands bound to copper did not influence the reactivity of the binuclear copper complexes so long as copper ions were held in close proximity. A metal-iodosylbenzene complex, such as suggested previously for Lewis acidic metal complex-catalyzed epoxidation by iodosylbenzene, is proposed as the active epoxidizing species. Some mechanistic aspects are discussed as well.