• 한국신재생에너지학회:학술대회논문집
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• 2007.11a
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• pp.623-626
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• 2007

킬른형 열분해 반응기를 이용하여 혼합폐플라스틱의 열분해로부터 얻어진 고분자성분의 열적분해 특성에 관한 연구를 TGA와 GC-MS를 이용하여 수행하였다. 열적분해의 속도론적 연구는 $10{\sim}50^{\circ}C/min$ 사이의 여러 가열속도에서 비등온 질량감소 기술을 이용하여 수행하였으며 활성화 에너지 및 반응 차수와 같은 속도 상수들에 대한 정보를 얻기 위하여 문헌에 제시된 여러 가지의 속도론 해석방법을 이용하여 질량감소곡선 및 그 미분 값을 해석하였다. 또한 회분식 열분해 반응기를 이용하여 반응온도에 따른 액상 생성물의 수율변화를 고찰하였으며 GC-MS를 이용하여 액상 생성물의 반응온도 증가에 따른 특성연구를 수행하였다.

• Journal of the Korean Chemical Society
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• v.52 no.3
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• pp.217-222
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• 2008

We investigate the kinetics of diffusion-influenced catalytic reactions occurring in small reaction volume. From a simple exact model study, we find that the reaction rate coefficient decreases with the size of reaction volume. The explicit expression for the average reaction rate constant is presented, which can be regarded as a generalization of well-known Collins-Kimball rate constant into the reactions occurring in a small reaction volume. It turns out that the traditional diffusion influenced reaction dynamics is followed by a single exponential relaxation phase with a rate constant dependent on the reaction volume for the catalytic reactions occurring in small reaction volumes.

• Journal of the Korean Chemical Society
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• v.48 no.3
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• pp.254-260
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• 2004

The reaction rates of para-substituted benzoyl chlorides ($p-CH_3$, p-H, $p-NO_2$) with pyridine have been measured employing the conductometry method in acetonitrile. The pseudo first-order and second-order rate constants were determined at various pressures and temperatures. The activation parameters (${\Delta}V{\ddagger},\;{\Delta}{\beta}{\ddagger},\;{\Delta}H{\ddagger},\;{\Delta}S{\ddagger},\;{\Delta}G{\ddagger}$) and the Hammett ${\rho}$-values are determined from the values of rate constant. The values of ${\Delta}V{\ddagger},\;{\Delta}{\beta}{\ddagger}\;and\;{\Delta}S{\ddagger}$ are all negative. The Hammett ${\rho}$-values are positive for the substrate (${\rho}_Y$) over the given pressure range. The results of kinetic studies, for the pressure and substituent changes, show that these reactions are proceeded by a typical $SN_2$reaction mechanism and its bond formation is favored with elevating pressure.

• Korean Chemical Engineering Research
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• v.47 no.3
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• pp.373-379
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• 2009

Cesium carbonate was used as an adsorbent to capture carbon dioxide from gaseous stream of carbon dioxide, nitrogen, and moisture in a fixed-bed to obtain the breakthrough data of $CO_2$. The deactivation model in the non-catalytic heterogeneous reaction systems is used to analyze the sorption kinetics among carbon dioxide, carbonate, and moisture using the experimental breakthrough data. The experimental breakthrough data are fitted very well to the deactivation model than the adsorption isotherm models in the literature.

• Journal of the Korean Chemical Society
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• v.20 no.6
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• pp.453-459
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• 1976

Rate constants for the reaction of methyl chloroformate with substituted anilines, and for the halogen exchanges in phenyl chloroformate have been determined in acetone. Although the rate data can be interpreted equally well with the addition-elimination mechanism($S_AN$) involving an intermediate, results of MO and isotope effect studies strongly favor the synchronous ($S_N2$) mechanism for the reactions studied. It was concluded that for the fast reacting nucleophiles the transition state is of "late" type while for the slow reacting nucleophiles it is of "early" type.

• Electronics and Telecommunications Trends
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• v.22 no.2 s.104
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• pp.92-101
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• 2007

Lean six sigma는 six sigma에 lean 개념을 접목시켜, 부가가치를 창출하지 못하는 프로세스 단계를 먼저 제거하여 프로세스 속도나 사이클 타임을 향상시키는 프로세스개선 방법론을 의미한다. Six sigma의 최우선 목표가 품질 개선이라면 lean은 생산 공정의 낭비제거에 초점이 맞춰져 있다. 그러나 quality와 함께 speed, cost를 고려하지 않는다면 프로세스의 속도나 투자자본의 감소를 개선하기 어려울 것이다. Lean six sigma는 lean의 속도와 six sigma의 무결점, 이 두 가지에 집중하여 원치 않는 복잡성을 제거하고 고객에게 집중하고 무결점 서비스를 제공하는 것이다. 본 연구에서는 우편물류에 lean six sigma를 적용한 프로세스 개선 방법론을 제시한다.

• 한국전기화학회:학술대회논문집
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• 1999.10a
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• pp.58-58
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• 1999

• Proceedings of the Materials Research Society of Korea Conference
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• 2001.05a
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• pp.162-162
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• 2001

• Proceedings of the Materials Research Society of Korea Conference
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• 1995.11a
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• pp.116-116
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• 1995

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2017.10a
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• pp.143-143
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• 2017