• Applied Chemistry for Engineering
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• v.8 no.5
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• pp.737-741
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• 1997

The typical removal method of volatile organic compounds is adsorption process. In this study, granular activated carbon and activated carbon fiber were used as adsorbents, and the adsorption behavior for the two types of adsorbent was compared. And they were regenerated by supercritical carbon dioxide extraction at a constant temperature, 318.15 K, and 2000, 2500, 3000 psi respectively. The desorption percentage of initial adsorbates and iodine values were increased with pressure of supercritical carbon dioxide. The regeneration time was 70 and 60 minutes in adsorbents loaded with methyl ethyl ketone(MEK) and benzene, respectively. The desorption percentages were 64.0% for granular activated carbon and 55.3% for activated carbon fiber loaded with MEK, and 59.1% for granular activated carbon and 45.2% for activated carbon fiber loaded with benzene. The exit concentration could be evaluated by Tan and Liou model. Therefore, the granular activated carbon and the activated carbon fiber could be regenerated by supercritical fluid extraction process.

• Proceedings of the SAREK Conference
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• 2007.06a
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• pp.103-103
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• 2007

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2005.05a
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• pp.721-724
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• 2005

With the advantages of large vibration energy dissipation of structures, the granular materials are used as vibration and acoustic treatments. In this case of vibro acoustic controls, a finite dynamic strength of the solid component (frame) is an important design factor. The dynamic stiffness of hollow cylindrical beams containing porous and granular materials as damping treatment was measured. Using the Rayleigh-Ritz method, the effects of damping materials on the dynamic characteristics of beams were investigated. The results suggested that the acoustic structure Interaction between the frame and the structure enhances the dissipation of the vibration energy significantly. The same methods were applied also to vibration control of sandwich panels. By filling the cavities of honeycomb cores using unconsolidated granular materials, its sound transmission toss was improved significantly.

• Proceedings of the KAIS Fall Conference
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• 2011.12a
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• pp.289-291
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• 2011

저온용 Mn-Cu계 촉매의 적정 적용온도를 파악하기 위해 다양한 조건에서 소성하였으며 소성한 촉매를 사용하여 반응온도, 유속 등에 따른 탈질효율 변화를 조사하였다. 실험결과 촉매의 전처리과정에서 바나듐-티타니아계 촉매보다 낮은 일정온도 이상으로 적용시 촉매의 산화가, pore 등에서 변화가 일어나며 궁극적으로 활성저하로 귀결됨을 알 수 있었다.

• The monthly packaging world
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• s.201
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• pp.106-117
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• 2010

올해 31회를 맞이한 일본 패키징 콘테스트는 지난 6월 18일에 열린 엄정한 심사에서 300건의 응모작품 중에 12점의 재팬 스타상 및 33건의 포장기술상, 63건의 포장부문상의 합 108점의 입상 작품이 결정되었다. 이번 일본패키징콘테스트출품작 전체적인 경향은 환경대응형 패키지, 유니버설디자인을 고려한 포장 등 환경과 인간을 테마로 한 것이 많이 보였다. 본 고에서는 심사위원의 강평을 일본패키징콘테스트를 평가해 보고 일본 포장산업을 전망해 본다.

• Proceedings of the Korean Nuclear Society Conference
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• 1998.05b
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• pp.385-390
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• 1998

방사성 페이온교환수지 아스팔트고화체를 처분장 등지에서 장기간 저장시 안전성 확보를 위하여 물리적 강도가 높고 고화체내에서 방사성핵종의 침출저항성 및 처리시 감용의 효과가 우수한 고화체 연구가 필요하게 되었다. 실험에 사용된 이온교환수지는 입상형 양이온 교환수지를 대상으로 하였으며 고화매질로서는 도로포장용으로 생산되는 직류아스팔트 60/70을 사용하였다. 고화보조제는 방사성 고체패기물 포장시 사용되어 폐기물로 발생되는 페폴리에틸렌(폐PE) 필름을 사용하였다. 실험결과 고화체의 형태안정성은 PE 함유량이 10 wt% 이상일 때 고화체 형태를 그대로 유지할 수 있으며 압축강도는 414 kPa(60 psi) 이상을 나타내었다. 최적의 운전조건은 이온교환수지, PE 함유량이 건조기준으로 각각 30~50 wt%, 10~25 wt% 이며, 고화온도는 170~20$0^{\circ}C$이다. 고화체의 침출특성은 확산 (diffusion) 으로 해석이 가능하며, 유효확산계수(De)는 Cs, Co의 경우 각각 1.621$\times$$10^{-7}$, 1.186$\times$$10^{-9}$ $\textrm{cm}^2$/day로 나타나고, Leachablity index는 각각 11.7, 13.8로 미국 원자력위원회 (NRC)가 요구하는 기준값 6보다 훨씬 높게 나타났다.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2021.11a
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• pp.19-20
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• 2021

In order to reduce the emission of harmful substances that degrade indoor air quality, the Ministry of Environment strengthened the standards for the content of VOCs in paints to supply and sell eco-friendly paints. In this related study, an eco-friendly paint mixed with a powder-type absorbent material was prepared and its characteristics were reviewed. As the amount of powder-type absorbent material increased, the workability (viscosity, peeling, etc) decreased. Accordingly, this study aims to examine which particle size is suitable according to the particle size of the granular adsorbent while improving the problem of the powdery adsorbent by using the granular adsorbent. As an experimental plan, the particle size of granular activated clay is selected to be 0.250, 0.425, 0.710(mm), and the decrease rate of VOCs concentration and impact resistance are reviewed. As a result of the experiment, as the particle size of the granular activated clay increased, the decrease rate of the VOCs concentration increased and the impact resistance improved. Therefore, considering the problems that occur after actual painting, the particle size of granular activated clay of 0.425mm is suitable.

• Fire Science and Engineering
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• v.34 no.1
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• pp.47-54
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• 2020

This paper proposes a solution to the problems of constructing and installing sway braces for existing standpipes in narrow spaces and pits. The study develops a floor-fixed sway brace for a narrow space that can support the ground area under horizontal seismic loads (X-axis, Y-axis) as well as vertical seismic loads (Z-axis). The results of structural analysis using SolidWorks simulation showed that the eccentric load was generated in the first design according to the anchored position along the vertical direction, and the problem of exceeding the allowable stress of the material along the horizontal and vertical directions. In the second design model, deformation caused by the eccentric load along the vertical direction, similar to the first design model, did not occur. The maximum strain rate was 0.17%, which is approximately 12.84% less than the first design model (Maximum strain rate of 13.01%). It was confirmed that the structural stability and durability improved. Compressive and tensile load testing of the prototypes showed that all of them meet the performance criteria of the standard.

• Journal of Korean Society of Forest Science
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• v.88 no.2
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• pp.213-220
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• 1999

The pollen morphology of six taxa of the genus Indigofera in Korea was investigated by light microscope(LM) and scanning electron microscope(SEM). The pollen grains of the genus were monads, prolate spheroidal or subprolate, and trizonocolporate. Sculpture patterns of mesocolpium area were densely microperforate(DMIP) or verrucate with pitted perforate striae(VPPS). Based on sculpture patterns in mesocolpium, apocolpium and colpus areas, three major pollen types of Indigofera were discernible ; Decora, Kirilowii and Koreana. It seemed as if there was some relationship between chromosome numbers and mesocolpium sculpture patterns and the pollen types Decora and Kirilowii were branched out from the pollen type Koreana.

• Economic and Environmental Geology
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• v.35 no.3
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• pp.191-201
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• 2002

The Gubong gold-silver deposits if gold-silver-bearing hydrothermal massive quartz veins which were filled the fractures along fault shear (NE, NW) zones within Precambrian banded or granitic gneiss of Gyeonggi massif. Ore mineralization of this deposits is contained within a single stage of quartz vein which was formed by multiple episodes of fracturing and healing. Ore minerals are comported mainly of arsenopyrite, pyrite, sphalerite, chalcopyrite, galena with minor amounts of pyrrhotite, marcasite and electrum. The frequency and volume percentages of electrum associated with ore minerals from this deposits are recognized as follows; 44.5% and 54.3% with arsenopyrite, 24.3% and 33.8% with quartz, 12.6% and 0.1% with pyrite, 11.0% and 4.8% with galena, 5.0% and 7.0% with sphalerite and 2.5% and 0.02% with chalcopyrite, respectively. They show irregular (41.6%), subround (34.7%), elongate (17.0%) and granular (6.6%) shapes, respectively. Their grain size ranges from 2 to 150 um, but 90.9 percent of the grains are below 30 um. The chemical composition of electrums ranges from 26.39 to 72.51 Au atomic %. These composition (Au atomic %) on the basis of associated minerals are from 44.97 to 71.75 with arsenopyrite, pyrite, sphalerite and quartz, from 44.37 to 72.51 with quartz, from 35.40 to 41.01 with sphalerite and chalcopyrite, from 26.39 to 54.84 with pyrite, chalcopyrite, quartz and galena, from 28.49 to 53.28 with galena, respectively. We suggest that optimum recovery of gold would be obtained with reference to these results.