• 한국신재생에너지학회:학술대회논문집
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• 2009.06a
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• pp.698-698
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• 2009

화력발전이 많은 비중을 차지하는 전력생산 산업은 온실가스($CO_2$)의 최대 배출 원으로 알려져 있으며 증가하는 전력 수요 뿐 만 아니라 다가오는 기후변화협약에 대응하기 위하여 $CO_2$ 회수 및 공정 개선에 관한 연구가 많이 수행되고 있다. 특히 현재 연구되고 있는 전력분야의 대표적인 $CO_2$ 회수기술은 연소 후 포집(Post-combustion capture), 순산소 연소(Oxy-fuel combustion), 연소전 탈탄소화(Pre-combustion) 3가지로 구분된다. 이중 연소전 탈탄소화 기술은 석탄가스화복합발전(IGCC) 기술과 연계하여 $CO_2$를 회수할 수 있는 방법으로 가스화 된 석탄가스에 Water-Gas Shift 반응과, $CO_2$ 분리로 얻어진 탈 탄소 연료를 통해서 전력을 생산한다. 이 기술의 핵심은 생성된 $CO_2/H_2$ 복합가스로부터 $CO_2$를 분리하는 공정으로 차세대 회수 기술로는 Membrance Reactor, SOFC, Oxygen Ion Transfer Membrane(OTM), 그리고 가스 하이드레이트가 있다. 이중 가스 하이드레이트는 $CO_2$의 회수 뿐 만 아니라 처리 기술에도 적용 가능하지만 우리나라에는 이에 관한 기술이 전무한 형편이다. 본 연구에서는 가스 하이드레이트 형성원리를 이용하여 정온 정압 조건에서 $CO_2/H_2$ 하이드레이트를 제조하였으며 특히, 하이드레이트 형성 촉진제인 THF(Tetrahydrofuran)를 첨가하여 THF 농도에 따른 상평형 및 속도론 실험을 수행 하였다. 이러한 연구는 연소전 탄소화 기술에서의 $CO_2$ 회수 분리에 대한 핵심 연구임과 동시에 탄소배출권 규제에 실질적인 기여를 할 수 있을 것으로 사료된다.

• Applied Chemistry for Engineering
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• v.31 no.4
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• pp.360-367
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• 2020

In this study, the accumulation and distribution routes of microplastics in soil environment were examined, and their analytical methodologies were summarized. Density separation and removal process of inhibition materials were introduced for the separation of microplastics in soil and the basic principles and limitations of quantitative and qualitative analyses including pyrolysis gas chromatography mass spectrometry, µ-Raman spectrometry, fourier transform infrared spectrometry, and microscopes were investigated. Chemical extraction methods for the analysis of mediated hazardous substance (additives and sorbed matters) in microplastics were also discussed with focusing on in vitro bioaccessibility assay for the human oral exposure route. Based on the described methodologies for the analysis of microplastics in soil, it is expected that these methods enable to select appropriate analysis techniques in consideration of medium state, contamination level and sample quantity.

• Journal of Environmental Impact Assessment
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• v.7 no.1
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• pp.109-116
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• 1998

As of July 1997, the registered number of automobiles exceeded 10 million and Korean auto industry produced 2,850,000 cars. Many environmentalists warn that the passenger cars are not sustainable urban transportation system in large cities. The cars produce about 80% of air pollutants, and consume 30% of petroleum imported. For the past 30 years the administration increased the road system, but the length of road per car is decreased from 813m in 1965 to 9m in 1995. The cost of traffic congestion was estimated to be \14.7 trillion in 1996, and is feared to increase without changing the present transportation system. The undesirable impact of cars include the casualties from traffic accidents, insurance loss, and separation of human relatioships. To construct sustainable urban transportation system, three principles should be followed. The first principle is to make the urban streets walkable for the people. The second principle is to encourage bicycling. Roads and traffic systems should be designed to let bicylces travel safely. The third principle is to supply more buses and construct integrated transportation system based on buses. The subway system is too expensive to construct and without the support of a well-organized bus system it may not work efficiently. The Brazilian city of Curitiba has constructed a very efficient bus system only with 1/80 of the estimated cost of subway system. The car-oriented transportation system does not seem to be an envrironmentally sustainable transportation system in most of the Korean cities.

• Natural Product Sciences
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• v.21 no.1
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• pp.1-5
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• 2015

Activity-guided separation of the methylene chloride-soluble fraction of the leaves of Zanthoxylum schinifolium, resulted in the isolation of four coumarinoids (1 - 4), two triterpenoids (5, 6) and three fatty acid derivatives (7 - 9) as active principles. Their chemical structures were identified as collinin (1), 8-methoxyanisocoumarin (2), 7-(6'R-hydroxy-3',7'-dimethylocta-2',7'-dienyloxy)-coumarin (3), (E)-4-methly-6-(coumarin-7'-yloxy) hex-4-enal (4), lupeol (5), epi-lupeol (6), phytol (7), hexadec-3-enoic acid (8) and palmitic acid (9), on the basis of spectroscopic (1D, 2D and MS) data analyses and comparing with the data published in the literatures. Compounds 1 and 7 showed potent cytotoxicity against Jurkat T cells with $IC_{50}$ values of 45.58 and $47.51{\mu}M$, respectively. The others showed moderate activity with $IC_{50}$ values ranging around 80.58 to $85.83{\mu}M$, while the positive control, auraptene, possessed an $IC_{50}$ value of $55.36{\mu}M$.

• Applied Chemistry for Engineering
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• v.24 no.4
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• pp.337-343
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• 2013

Membrane reactors have been showing a promising future and attracted increasing attention in the scientific community as they possess advantages in terms of enhanced catalytic activity and selectivity, combination of processes (reaction and separation), simplicity in process design, and safety in operation. In particular, solid electrolyte membrane reactor principles are realized in fuel cells, electrolyzers and reactors for hydrogenation of carbon dioxide and other economically viable reactions. In this review, as a young generation of ion conducting materials, high temperature proton conductors are discussed in terms of the current status of material development and their various applications.

• Journal of the Korean housing association
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• v.15 no.1
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• pp.85-93
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• 2004

This study does try to proceed on the assumption that complex buildings can vitalize urban life of contemporary society from contemporary complexity and cases of past failure. The scope of investigation on complex buildings in Sangju built in 1990s' and 2000s' on this thesis is that site size is 400 square meter, total area 1500 square meter, and the number of stories on the ground below 5 floor. Method of investigation on twenty one buildings which have been built on new C.B.D. between the Namwon avenue and the Joongang 1th street in Sangju is through field investigation, field photographs, recordings and drawings on these buildings. Investigative contents have been divided and analysized into physical and functional elements in urban and architectural dimension. On the basis of these results, the future planning approach of complex buildings in medium and small cities has been considered into planning principles of convenience of building use and efficiency of site size, physical plans reflected on the traffic and pedestrian movings and the face of buildings, pedestrian resting space-creation like plazas and central gardens, regional character reflected with urban context, and separation and union of approached movings interrelated among the components.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.10a
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• pp.268-276
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• 2008

The status of contaminated soils vary widely ; therefore, the techniques and equipment applicable to the soil concerned should be selected and used after careful consideration. Hyundai Soil Washing is physical-chemical separation based on mining and mineral processing principles for removing a broad range of organic and inorganic contaminants from soil. Mobile plant(capacity 15 tons./hr) was installed for this project. The goals of this project were 1) to verify the applicability of the washing process, which showed reliable results in the pilot plant with various kind of contaminated soils and 2) to promote recycling of the washed soil as a backfill on site. The results revealed that $F^-$ and $Pb^{2+}$ in the soil were effectively washed out to a certain level which washed soil was acceptable for recyeling.

• Archives of Pharmacal Research
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• v.28 no.8
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• pp.892-896
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• 2005

In order to isolate substances that inhibit the hemolytic activity of human serum against eryth-rocytes, we have evaluated whole plants of the Orostachys japonicus species with regard to its anti-complement activity, and have identified its active principles following activity-guided isolation. A methanol extract of the O. japonicus, as well as its n-hexane soluble fraction, exhibited significant anti-complement activity on the complement system, which was expressed as total hemolytic activity. A bioassay-guided chromatographic separation of the constituents resulted in the isolation of three known compounds 1-3 from the active n-hexane fraction. The structure of these compounds were analyzed, and they were identified as hydroxyhopanone (1), $\beta-sitosteryl-3-O-\beta-D-glucopyranosyl-6'-O-palmitate$ (2), and $\beta-sitosteryl-3-O-\beta-D-glucopyranoside$ (3), respectively. Of these compounds, compound 2 exhibited potent anti-complement activity $(IC_{50}=1.0\pm0.1{\mu}M)$ on the classical pathway of the complement, as compared to tiliroside $(IC_{50}=76.5\pm1.1{\mu}M)$, which was used as a positive control. However, compounds 1 and 3 exhibited no activity in this system.

• Proceedings of the Korean Society for Quality Management Conference
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• 2006.04a
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• pp.54-65
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• 2006

Since the ending of the IMF period, the Korean health industry has experienced a number of changes in its environment such as hospital bankruptcy, enforcement of SDF(Separation of Dispensing and Prescription), opening of the medical market by WHO, evaluation of medical institutions with more than 100 sick beds, and limited approval for medical service advertisement. Furthermore, the concept of medical service has changed from a beneficent and vortical one to a hi lateral and righteous one. These changes in medical service have required medical institutions to provide customers with medical service options and adopt market principles actively, while considering customer satisfaction. Thus, this paper aims to investigate the service quality and service value of medical institutions, to understand the mutual relationship between customer satisfaction and repeat visits, and to suggest better solutions for the improvement of service quality. For future studies, It will be necessary to overcome the limitations of this research and develop proper measurement tools on service quality in the Korean medical system.

• Biomolecules & Therapeutics
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• v.25 no.2
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• pp.165-170
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• 2017

Cordyceps bassiana is one of Cordyceps species with anti-oxidative, anti-cancer, anti-inflammatory, anti-diabetic, anti-obesity, anti-angiogenic, and anti-nociceptive activities. This mushroom has recently demonstrated to have an ability to reduce 2,4-dinitrofluorobenzene-induced atopic dermatitis symptoms in NC/Nga mice. In this study, we further examined phytochemical properties of this mushroom by column chromatography and HPLC analysis. By chromatographic separation and spectroscopic analysis, 8 compounds, such as 1,9-dimethylguanine (1), adenosine (2), uridine (3), nicotinamide (4), 3-methyluracil (5), 1,7-dimethylxanthine (6), nudifloric acid (7), and mannitol (8) were identified from 6 different fractions and 4 more subfractions. Through evaluation of their anti-inflammatory activities using reporter gene assay and mRNA analysis, compound 1 was found to block luciferase activity induced by $NF-{\kappa}B$ and AP-1, suppress the mRNA levels of cyclooxygenase (COX)-2 and tumor necrosis factor $(TNF)-{\alpha}$. Therefore, our data strongly suggests that compound 1 acts as one of major principles in Cordyceps bassiana with anti-inflammatory and anti-atopic dermatitis activities.