• Bulletin of the Korean Chemical Society
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• 제35권5호
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• pp.1403-1408
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• 2014

The cycloaddition reactions of the N-heterocyclic carbene boryl azide with methyl acrylate, butenone, and hexafluoropropene have been investigated theoretically. Solvent effects on these reactions have been explored by calculation that included a polarizable continuum model (PCM) for the solvent (C6H6). The title reaction could produce 4- and 5-substituted 1,2,3-triazolines, respectively. The reaction systems have the higher chemical reactivity with the low barriers and could be favored. Yet the smaller differences have been found to occur in energetics, and the cycloaddition reactions occur for s-trans conformations over s-cis conformations. The calculations indicated that the cycloaddition reaction of the alkenes have certain regioselectivity.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 1993년도 춘계학술대회 및 공장견학
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• pp.112-117
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• 1993

최근의 급속한 산업발전에 의해 각종 기계나 내연기관의 운전조건이 가혹해 짐에 따라 윤활유의 물성도 점차 고성능화 되는 추세로 광유계윤활유에서 볼수 없는 높은 점도지수, 낮은 저온유동성, 우수한 화학적안정성등의 특성을 얻기 위해 유기합성방법에 의해 인위적으로 합성한 원료를 기유로 사용한 윤활유를 합성윤활유라 하며 합성기유는 작용기 종류, 합성방법에 다라 다양하게 분류된다. 합성윤활유의 종류에는 일반적으로 합성방법에 따라 폴리머형(P형)과 비폴리머형(N형)으로 대별되는데 폴리며형 합성에는 polybutene, polyalkyleneglycole, poly $\alpha$-olefin (PAO)와 diester가 주로 사용되고 있다. 본 연구에서는 그간 연구해온 광유계윤활유의 첨가제 합성, 혼련기술 및 PAO와 diester합성기술을 기초로 내연기관용 고성능 합성윤활유 혼련기술 개발과 더 나아가 항공기작동유나 Jet-engine유등 특수 윤활유 개발에 연구목적이 있다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2004년도 추계학술대회 논문집
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• pp.34-37
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• 2004

In the present research, a ultra-precision diamond cutting of thermo-plastic materials, polycarbonate (PC) and cyclic olefin polymer (COC), is carried out by applying a method named ultrasonic elliptical vibration cutting developed by the authors. It is experimentally proved that good optical surfaces are obtained by applying the elliptical vibration cutting in cases of machining of flat surfaces and grooves as compared with the conventional diamond cutting. The maximum surface roughness in peak to valley value obtained is less than 60 nm and 20 nm for PC and ZEONEX, respectively.

• 한국에너지공학회:학술대회논문집
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• 한국에너지공학회 2010년도 춘계학술 발표회
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• pp.199-199
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• 2010

Polymeric membranes have been widely used to separate gas mixtures, such as $O_2/N_2,\;CO_2/CH_4,\;CO_2/N_2$, and olefin/paraffin. The permeation selectivity is the ratio between composition ratio at the permeate side and composition ratio at the feed side. In addition, the permeation selectivity is a product of solubility selectivity and diffusivity selectivity. We present a novel idea and describe its experimental result, which was achieved by preparing polymer gel films that included a room temperature ionic liquid (RTIL) in a polymer matrix. It is known that $CO_2$ can dissolve easily in imidazolium-based RTILs. We prepared polymer-ionic liquid gel films using an ionic liquid, 1-ethyl-3-methylimidazolium acetate ([emim] acetate, C-tri) and a host polymer, poly (vinyl acetate) (PVAc, Aldrich).

• 한국응용과학기술학회지
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• 제19권3호
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• pp.206-212
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• 2002

The catalytic activities of several metalloporphyrin, wherein the porphyrins are TPP(5,lO,l5,20-Tetraphenyl-21H,23H-porphyrin) and (p-X)TPP (X =$CH_{3}O$, $CH_{3}$, F, Cl), are reported for the oxidation of styrene and it's derivatives. The electronic effects of substrates and porphyrins on the catalytic activity of metalloporphyrin containing the transition metal ion such as Mn(III) was discussed. Investigating the correlation between the Michaelis-Menten's rate parameters and the substituent constants, we are going to analyze the influences on the changes of catalytic activity or rate determining step during the processes of the formation and the dissociation of the M-oxo-olefin.

• 자연과학논문집
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• 제5권2호
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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 $(C_4H_6)_x$.

• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.307-307
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• 2006

The reduction behavior of silver ions to silver nanoparticles is an important research topic in polymer/silver salt complex membranes for facilitated olefin transport, because it has a significant effect on the long-term stability of membrane performance. In this study, the effects of solvent on the formation of silver nanoparticles and long-term membrane performance in polymer/silver salt complex membrane were investigated. This effect was assessed for the complexes of poly(N-vinyl pyrrolidone) $(PVP)/AgBF_{4}$ with the use of ionic liquid (IL), acetonitrile (ACN) and water as a solvent. Membrane performance test shows that long-term stability is strongly dependent on the kind of solvent and arranged: IL > ACN >> water.

• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.150-151
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• 2006

Perfluoroaryl boranes are widely employed as co-catalysts in olefin polymerization processes. Perfluoroaryl diboranes, possessing borane centers in close proximity, are a subclass of this family of compounds that are in theory capable of chelating neutral and anionic bases. The resulting anions are exceptionally weakly coordinating. We have prepared examples of such compounds and studied their coordination behavior with neutral Lewis bases that have the capability to bridge Lewis acid sites in an effort to delineate the kinetic and thermodynamic factors that influence bonding mode. When protic Lewis bases such as alcohols or water are reacted with diboranes, strong Bronsted acids capable of initiating cationic polymerizations under unusual conditions result.

• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.222-222
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• 2006

New types of constrained geometry complexes comprising rigid silacycloalkyl group incorporated into the bridging position between cyclopentadienyl and amido functionalities were prepared. The catalytic activities of olefin polymerization were influenced by the change of exo-cyclic ring size on bridge-head silacycloalkyl unit. It has been noted that the activities of this unique series increase with increasing size of the silacycloalkyl bridge and reach the maximum in six-membered silacyclohexyl-bridged CGC complex. It is noteworthy that conformation of silacycloalkanes gives rise to enhanced catalytic activity of the titanium center although the cyclic ring and titanium center are far remoted from each other.

• Biomolecules & Therapeutics
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• 제9권3호
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• pp.143-155
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• 2001

Many attention has been focused on developing new chemotherapeutic agents for a treatment of cancer from natural products. From Carpesium divaricatum S. et Z. (Compositae), various monoterpenoid compounds were isolated and exhibited mild antitumor activity against human tumor cell lines. These facts prompted us to explore the structure-activity relationship of these compounds. The synthesis of monoterpenoid compound was accomplished by Fries rearrangement, Grignard reaction, elimination, allylic oxidation, esterification and epoxidation as key steps. The results of in vitro cytotoxicity (A549, SK-OV-3, SK-MEL-2, XF498, HCT15) of the synthesised compounds are as follows: First of all, epoxide moiety is prerequisite for cytotoxic activity in diester compound. Any kind of compounds with olefin or diol moiety instead of epoxide ring exhibited poor or mild cytotoxic activity respectively. Of o-acetoxy and isobutoxy epoxy esters, p-sub-stituted phenylacetate compounds exhibited high cytotoxic activities against SK-MEL-2 and HCT15.