• Journal of the Korean Chemical Society
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• v.24 no.1
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• pp.34-43
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• 1980

The reaction of thianthrene cation radical perchlorate with thioxanthene in acetonitrile gave thianthrene and dark reddish thioxanthylium ion instead of thioxanthene cation radical. Addition of aromatic nucleophiles such as anisole, aniline, N,N-diethylaniline, catechol, ethylbenzene, to the above mixture yielded the corresponding thioxanthenes with substituent at 9 position. Reactions with dibenzo-18-crown-6-ether, diphenylmercury, and triphenylphosphine gave similar products. However, reactions with aromatics with electron-withdrawing group were either too slow or inert to such a reaction.

• Proceedings of the Korean Fiber Society Conference
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• 2002.04a
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• pp.25-28
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• 2002

비공역형 단량체인 비닐아세테이트(VAc)는 공역형 비닐계 단량체와 달리 라디칼의 활성이 너무 커서 중합 도중 빈번한 연쇄이동반응과 정지반응에 의해 분지구조의 고분자가 얻어지며 고분자량의 폴리비닐아세테이트를 얻기가 어려운 것으로 알려져 있다. 폴리비닐알코올(PVA)은 비닐알코을 단량체의 호변이성질화 때문에 단량체의 직적중합에 의해서는 얻을 수 없고 일반적으로 비닐아세테이트(VAc)를 라디칼 중합하여 얻어진 폴리비닐아세테이트(PVAc)를 비누화하여 합성한다. (중략)

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 2003.10a
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• pp.54-59
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• 2003

유기과산화물은 분자구조내에 과산화결합(Peroxy, -O-O-)을 갖고 있는 유기화합물로서 매우 불안정한 과산화수소(H-O-O-H)의 유도체이다. 과산화물을 특징짓는 산소-산소(-O-O-) 과산화결합은 C-H, C-O, C-C 등의 결합에 비하여 결합에너지가 작아서 열이나 빛에 의해서 쉽게 균형분해(Homolysis)가 일어나 두 개의 유리기인 라디칼(Free radical)을 생성하게 되는데, 이때 생성된 라디칼은 비닐중합반응을 개시시킬 수 있고, 또한 다른 자유 라디칼 반응을 유발시킬 수 있다.(중략)

• Applied Chemistry for Engineering
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• v.5 no.3
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• pp.438-442
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• 1994

A very useful cation radical, triphenylaminium hexachloroantimonate, was quantitatively incorporated into insoluble polymer framework. The polymer cation radical was found to be effective as a catalyst in the Diels-Alder type dimerization and then shown to be reusable through several cycles of use.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 1999.11a
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• pp.53-56
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• 1999

석탄 연소로 내에서는 어떠한 방식으로든 NH- 라디칼이 존재하게 된다. 즉, 배가스 처리 공정에서는 SNCR 방식에 의해 질소산화물 (NO) 저감할 경우 환원제로써 사용되는 암모니아 또는 요소와 같은 물질은 고온의 연소로에서 NH- 라디칼을 생성하게 되기도 하며, 순환유동층 연소로처럼 석탄을 원료로 사용하는 연소로에서는 석탄내에 포함되어 있는 N, H와 같은 원소들이 휘발하여 NH- 라디칼이 생성되기도 한다.(중략)

• Journal of the Korean Chemical Society
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• v.26 no.1
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• pp.1-6
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• 1982

The addition of thiophenol to ${\alpha}$-methylstyrene has been studied MO theoretically using CNDO/2 method. Although overall reaction proceeds in two steps i.e., (1) decomposition of thiophenol to give phenylthiyl radical and (2) addition of the radical to ${\alpha}$-methylstyrene to give a new monomer radical, theoretical results suggested that the phenylthiyl radical formation step, (1), was the dominant process in determining the rate of addition; this was the rationale behind the negative ${\rho}$ value obtained experimentally from the Hammett plots for substituents on the thiyl radicals. The departure from a linear Hammett plot for addition of ${\rho}$-chlorophenylthiyl and m-trifluoromethyl phenylthiyl to ${\rho}$-methoxy-${\alpha}$-methylstyrene could be explained as a result of an increased contribution of the addition step, (2) to the overall reaction rate.

• Journal of Adhesion and Interface
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• v.15 no.1
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• pp.22-30
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• 2014

Self-photoinitiating acrylate (SPIA) which can undergo self-initiation under UV irradiation was synthesized by a Michael addition in the presence of a base catalyst. The SPIA polymerizations were investigated by photo-differential scanning calorimeter (photo-DSC) and surface physical properties such as pendulum hardness and pencil hardness. The results showed that the SPIA can cure upon UV irradiation by itself without a photoinitiator. But we found out that both the curing rate and the conversion were too low for the self-curing reaction of SPIA. In order to improve the SPIA curing properties, we introduced the SPIA/cationic hybrid system and observed the effects of the addition of commercial free radical type monomer and photoinitiator on the curing behaviors. SPIA/cationic hybrid system was the best suitable to improve the SPIA curing properties. The kinetic analysis indicated that the cationic monomer and photoinitiator apparently accelerated the cure reaction and rate of the hybrid SPIA system, mostly due to the synergistic effect of cationic monomer and photoinitiator increasing the mobility of active species and the generation of reactive species (free radical, cation) during the photopolymerization process. The physical properties showed that, unlike typical free radical system, the hybrid systems did not show oxygen inhibition effect because of cationic reaction on the coating surface.

• Journal of the Korean Chemical Society
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• v.49 no.1
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• pp.63-71
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• 2005

• Korean Chemical Engineering Research
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• v.51 no.4
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• pp.523-526
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• 2013

In order to purify the waste water containing natural fatty oil, hydroxy radical and/or ozone are used to remove the fatty oil dispersed in the waste water. The fatty oil is decomposed by oxidation reaction through hydroxy radical and ozone, and eliminated as a function of first order reaction. It is clearly confirmed that the fatty oil in waste water can be effectively removed much more in the use of both hydroxy radical and ozone than only hydroxy radical as an oxydant. In addition, the decomposition chemical reaction mechanism of the fatty oil by hydroxy radical and ozone is proposed.

• Journal of the Korean Society of Hazard Mitigation
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• v.11 no.2
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• pp.179-183
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• 2011

In this study, photochemical effects (OH radical formation) in the photoreactor was investigated to analyze UV-C intensity distribution. In addition, The influence radius of the UV-C lamp was measured at various dose of $TiO_2$ (Degussa P-25). The photoreactor used in this study was bath type reactor which is made by acrylic and the UV-C lamp (SANKYO DENKI, wavelength : 254 nm, Diameter : 2.2 cm, Length : 18.5 cm) was used as photo source. The maximum electric power consumption of the UV lamp was 10.5 W. The OH radical formation by UV-C was measured by KI dosimetry methods. From the results, the effective OH radical formation was occurred under the following condition. The reasonable distance of UV-C lamp is within 13 cm and the intensity of UV-C lamp should be more than 0.367 mW/$cm^2$. Moreover, the concentration of catalyst affects on the influence radius of the UV lamp.