• Natural Product Sciences
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• v.16 no.3
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• pp.185-191
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• 2010

Mast cell-mediated allergic disease is involved in many diseases such as anaphylaxis, asthma and atopic dermatitis. The discovery of drugs for the treatment of allergic disease is an important subject in human health. In the present study, the effect of water extract of Gleditsiae Spina (WGS) (Leguminosae), on compound 48/80-induced systemic allergic reaction, anti-DNP IgE antibody-induced local allergic reaction, and histamine release from human mast cell line (HMC-1) cells were studied. In addition, the effect of WGS on phorbol 12-myristate 13-acetate (PMA) plus calcium ionophore A23187 (A23187)-induced gene expression and secretion of pro-inflammatory cytokines were investigated using HMC-1 cells. WGS was anally administered to mice for high and fast absorption. WGS inhibited compound 48/80-induced systemic allergic reaction. WGS dose-dependently decreased the IgE-mediated passive cutaneous anaphylaxis. WGS reduced histamine release from HMC-1 cells. In addition, WGS decreased the gene expression and secretion of pro-inflammatory cytokines in PMA plus A23187-stimulated HMC-1 cells. These findings provide evidence that WGS could be a candidate as an antiallergic agent.

• Journal of Hydrogen and New Energy
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• v.25 no.4
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• pp.355-363
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• 2014

Thermal shock or overheating of WGS catalyst for SEWGS system during hydrogen pre-treatment can cause reactivity decay of the catalyst. To select appropriate pre-treatment condition, temperature profiles of catalyst bed (or outside fluidized particle bed of bed insert) during pre-treatment were measured and then CO conversions of those catalysts during WGS reaction were also measured and compared. Drastic overheating of catalyst took place when we reduce catalyst at fixed bed condition and these catalysts showed low CO conversion during WGS reaction. On the contrary, there was no overheating of catalyst at fluidized bed condition not only physical mixing case but also bed insert case. Spring type bed insert showed acceptable CO conversion even at low WGS content. Consequently, feasibility of high CO conversion without decay of reactivity of catalyst and holding the WGS catalyst inside the SEWGS reactor as tablet shape were confirmed using spring type bed insert.

• Journal of Hydrogen and New Energy
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• v.22 no.4
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• pp.465-473
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• 2011

To find the optimum mixing ratio of WGS catalyst with $CO_2$ absorbent for SEWGS process, water gas shift reaction tests were carried out in a fluidized bed reactor using commercial WGS catalyst and sand (as a substitute for $CO_2$ absorbent). WGS catalyst content, gas velocity, and steam/CO ratio were considered as experimental variables. CO conversion increased as the catalyst content increased during water gas shift reaction. Variations of the CO conversion with the catalyst content were small at low gas velocity. However, those variations increased at higher gas velocity. Within experimental range of this study, the optimum operating condition(steam/CO ratio=3, gas velocity = 0.03 m/s, catalyst content=10 wt.%) to get high CO conversion and $CO_2$ capture efficiency was confirmed. Moreover, long time water gas shift reaction tests up to 20 hours were carried out for two cases (catalyst content = 10 and 20 wt.%) and we could conclude that the WGS reactivity at those conditions was maintained up to 20 hours.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.15 no.2
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• pp.269-275
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• 1997

Car Navigation System with Global Positioning System (GPS) can display position direction and the shortest cut of one's destination. The position datum for GPS in World Geodetic System 1984 (WGS-84) coordinates system need to transform Bessel coordinates system and process Map projection. Since 1987, GPS has used the WGS-84. WGS-84 is a geocentric equipotential ellipsoid of revolution which is defined four parameters. In this study, by comparing the digitized topographical map with the digital map of GPS datum we can consider the technique of WGS84 digital map.

• 한국신재생에너지학회:학술대회논문집
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• 2010.06a
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• pp.111.1-111.1
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• 2010

석탄가스화복합발전(IGCC: Integrated Gasification Combined Cycle)의 고온 고압 합성가스로부터 $CO_2$를 저비용으로 포집하기 위한 연소전 포집 기술 중 유동층 촉진수성가스전환(SEWGS) 공정이 제안되어 연구개발 중에 있다. 연소전 $CO_2$ 포집을 위한 SEWGS 공정은 동일한 2탑 순환 유동층 반응기에서 고온 고압의 합성가스($H_2$, CO)를 유동층 WGS 촉매를 사용하여 CO를 $CO_2$로 전환하는 동시에 전환반응으로 생성된 $CO_2$를 흡수제를 이용하여 포집하는 기술이다. 본 연구는 $CO_2$ 회수와 WGS 반응이 동시에 이루어지는 공정에 적용 가능한 건식 재생 흡수제 및 유동층 WGS 촉매 개발을 목표로 $CO_2$ 흡수제(P Series) 및 WGS 촉매(PC Series) 조성을 제안하고 분무건조기를 이용하여 6~8kg/batch로 성형 제조하였다. 제조된 $CO_2$ 흡수제 및 촉매의 특성 평가 결과 내마모도(Attrition resistance)를 포함한 물리적 특성이 유동층 공정의 요구조건을 만족하는 결과를 얻을 수 있었다. 또한, 모사 석탄 합성가스를 이용하여 20bar, $200^{\circ}C$ 흡수/$400^{\circ}C$ 재생 조건에서 열중량 분석기(TGA) 및 가압 유동층(Fluidized-bed) 반응기를 통한 흡수제의 $CO_2$ 흡수능 평가를 수행하였다. 그 결과 내마모도(AI) 3% 이하로 기계적 강도가 우수하며, $CO_2$ 흡수능 17.6 wt%(TGA) 및 11wt%(가압 유동층)를 나타냈다. 유동층 WGS 특성 평가 결과 내마모도가 7~35%로 우수하였고, CO 전환율은 $200^{\circ}C$에서 80% 이상으로, 유동층 SEWGS 공정에 적용 가능한 특성을 확인하였다.

• Journal of Hydrogen and New Energy
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• v.24 no.6
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• pp.535-542
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• 2013

To enhance the performance of SEWGS system by holding the WGS catalyst in a SEWGS reactor using bed inserts, effect of bed insert geometry on CO conversion of WGS catalyst was measured and investigated. Small scale fluidized bed reactor was used as experimental apparatus and tablet shaped WGS catalyst and sand particle were used as bed materials. The cylinder type and the spring type bed inserts were used to hold the WGS catalysts. The CO conversion of WGS catalyst with the change of steam/CO ratio was determined based on the exit gas analysis. Moreover, gas flow direction was confirmed by bed pressure drop measurement for each case. The measured CO conversion using the bed inserts showed high value comparable to previous results even though at low catalyst content. Most of input gas flowed through the bed center side when we charged tablet type catalyst into the cylinder type bed insert and this can cause low $CO_2$ capture efficiency because the possibility of contact between input gas and $CO_2$ absorbent is low in this case. However, the spring type bed insert showed good reactivity and good distribution of gas, and therefore, the spring type bed insert was selected as the best bed insert for SEWGS process.

• Journal of Hydrogen and New Energy
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• v.22 no.6
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• pp.905-912
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• 2011

In this study, the novel concept catalytic reactor was designed for water-gas shift reaction (WGS) under high pressure. The novel concept catalytic reactor was composed of an autoclave, the catalyst, and liquid water. Cu-ZnO/$Al_2O_3$ as the low temperature shift catalyst was used for WGS reaction. WGS in the novel concept catalytic reactor was carried out at the ranges of 150~$250^{\circ}C$ and 30~50 atm. The liquid water was filled at the bottom of the autoclave catalytic reactor and the catalyst of pellet type was located at the gas-liquid water interface. It was concluded that WGS reaction occurred over the surface of catalysts partially wetted with liquid water. The conversion of CO for WGS was also controlled with changing content of Cu and ZnO used as the catalytic active components. Meanwhile, the catalyst of honey comb type coated with Cu-ZnO/$Al_2O_3$ was used in order to increase the contact area between wet-surface of catalyst and the reactants of gas phase. It was confirmed from these experiments that $H_2$/CO ratio of the simulated coal gas increased from 0.5 to 0.8 by WGS at gas-liquid water interface over the wet surface of honey comb type catalyst at $250^{\circ}C$ and 50 atm.

• Korean Chemical Engineering Research
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• v.51 no.4
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• pp.455-459
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• 2013

The fuel processor for the portable fuel cell includes multi-step processes consisting of hydrogen generator, heat generator and several CO clean-up stages. One of requirements of the fuel processor for portable fuel cell system is a rapid start-up time. Especially, the warm-up time for WGS reactor is crucial factors for total start-up time. In this paper, active heating protocol, which is the heating protocol of WGS reactor supplied by the oxidation of CO rich reformate in the initial stage, is used for a rapid start-up. The air stream fed to the inlet of WGS reactor rapidly oxidize the CO rich reformate in the WGS reactor. Therefore, CO concentration in reformate quickly stabilized at the desired concentration without CO surges.

• Journal of Hydrogen and New Energy
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• v.24 no.2
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• pp.150-159
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• 2013

To enhance the performance of SEWGS system by holding the WGS catalyst in a SEWGS reactor using bed inserts, effects of insert geometry and shape of WGS catalysts on CO conversion were measured and investigated. Small scale fluidized bed reactor was used as experimental apparatus and WGS catalyst (particle and tablet) and sand were used as bed materials. The parallel wall type and cross type bed inserts were used to hold the WGS catalysts. The CO conversion with steam/CO ratio was determined based on the exit gas analysis. The measured CO conversion using the bed inserts showed high value comparable to physical mixing cases. Moreover, gas flow direction was confirmed by bed pressure drop measurement for each case. Most of input gas flowed through the catalyst side when we charged tablet type catalyst into the bed insert and this can cause low $CO_2$ capture efficiency because the possibility of contact between input gas and $CO_2$ absorbent is low in this case. New bed insert geometry was proposed based on the results from this study to enhance contact between input gas and WGS catalyst and $CO_2$ absorbent.

• 한국신재생에너지학회:학술대회논문집
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• 2010.06a
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• pp.206.1-206.1
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• 2010

폐기물 등을 열분해 가스화한 합성가스로부터 효과적으로 고순도의 수소를 회수하기 위하여 WGS(수성가스전환반응) 및 $CO_2$ 회수 PSA 공정을 적용하였다. 벤치스케일 열교환형 WGS반응기를 개발하여 기존 단열방식에 비하여 단순화한 반응시스템을 구축하였으며 출구 CO농도 4%대를 달성하였다. 또한 3베드로 구성된 벤치스케일의 $CO_2$ PSA운전을 수행한 결과, 2.5barg 흡착 및 진공재생단계를 적용하여 회수되는 $CO_2$의 농도가 95%이상, 회수율 80%이상을 기록하는 효율적인 $CO_2$ 회수공정을 개발하였다. 한편, 흡탈착 모사프로그램인 ADSIM을 통해서도 실험과 비교적 일치한 결과를 얻을 수 있었는데 향후 스케일업 설계자료 확보시 유용할 것으로 판단되었다.