• 제목/요약/키워드: Permeating

검색결과 65건 처리시간 0.035초

지속 하중하에서 철근콘크리트 부재의 염화물 침투특성에 따른 철근부식에 관한 연구 (A Study on the Reinforcing Bar Corrosion Caused by Permeation of Chloride Ion Under Sustained Load)

  • 최일호;김형래;윤상천;지남용
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1999년도 학회창립 10주년 기념 1999년도 가을 학술발표회 논문집
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    • pp.779-782
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    • 1999
  • This study was carried out to estimate the effects of the loading conditions on the corrosion of reinforcing bars and permeation of chloride ion. The permeation of chlorides depends not only on the transfer properties in concrete but also on the load applied in the case of reinforced concrete structures. Recent studies reported that the loading conditions affected the corrosion rate of the reinforcing bars under existence of an external current supply. But it was not reported that loading conditions affected corrosion of reinforcing bar caused by the characteristics of permeation and the process of cracking. In this experiment, it was shown that the corrosion of reinforcing bars and the characteristics of permeating were greatly affected by the loading conditions.

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심층혼합처리 공법의 시공조건 및 환경적 영향 분석 (Analysis of Construction Condition and Environmental Effect of Deep Soil Mixing)

  • 조진우;이용수;유준;신원재
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2006년도 춘계 학술발표회 논문집
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    • pp.1155-1158
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    • 2006
  • This paper presents a study on the construction condition and environmental effect of deep soil mixing. Construction condition means the difference in unconfined compressive strength with respect to the depth and location of samples. Environmental effect means alkalinity diffused from soil stabilizer. The experimental results indicate that the unconfined compressive strength vary with respect to the depth, and doesn't show consistency pattern. So, in field application we must decide a mixing ratio enough to satisfy the least unconfined compressive strength. The difference in unconfined compressive strength with respect to the location of samples is negligible. The generation of alkalinity from soil stabilizer is reduced by permeating in non-improved soil and it is expected that the diffusion of alkalinity has no environmental effect on soil and ground water.

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Study on biopolymer delivery system and effect of wound healing with polysaccharide extracted from Agaricus blazei Murill

  • Kim, Min-Kyoung;Lee, Hye-Young;Hong, Eock-Kee
    • 한국생물공학회:학술대회논문집
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    • 한국생물공학회 2005년도 생물공학의 동향(XVII)
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    • pp.816-820
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    • 2005
  • Polysaccharide-based dressings have increasingly become viable alternatives to somewhat less biocompatible and often problematic cotton or viscose gauzes traditionally used for wound dressings. Polysaccharide which is particularly abundunt in Agaricus blazei Murill is known as the bioactive materials. Polysaccharide extracted from Agaricus blazei Murill enhances the recovery of the damaged epidermal tissue and the production of epithelial cell growth factors which are necessary to heal the burn and wound on the epidermal tissue. In this study, the biopolymer delivery system of polysaccharide extracted from Agaricus blazei Murill into epidermal tissue was elucidated using the skin permeating enhancer in vitro. The enhancing effects of various penetration enhancers and some other enhancers on the permeation of ${\beta}-glucan$ were evaluated using Franz diffusion cell. Permeation of polysaccharide in nomal and burn skin was compared. Polysaccharide was studied for the burn and wound healing activity in the epidermal tissue on rats.

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증산법에 의한 잣나무와 일본잎갈나무의 목부내 염료침투 (Dye Penetration into Xylem of Pinus koraiensis and Larix leptolepis by Transpiration Method)

  • 전수경
    • 한국가구학회지
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    • 제12권1호
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    • pp.1-9
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    • 2001
  • This study was carried out to elucidate the relationship between wood anatomy and the water flow path in P. koraiensis and L. leptolepis. through the experiment of penetration of the dye solution. The experiment was performed by permeating 1% acid, alkali and direct solution into the xylem just after being cut. The results obtained were summarized as follows : 1. In P. koraiensis and L. leptolepis, the dye solution penetrated into sapwood and annual rings adjacent to cambial zone were only dyed according to ascent of tree height. 2. The penetrability of latewood was better than that of earlywood. 3. In P. koraiensis and L. leptolepis, the main water flow path in longitudinal direction was the trachied and that in transverse direction was ray trachied and ray parenchyma. Also, the dye solution was found in resin canal. 4. P. koraiensis was more permeable than L. leptolepis. 5. Among the acid, alkali and direct dye solution, the acid dye solution was the most permeable.

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Pervaporation Separation of Trace VOCs from Water Through PDMS Membranes

  • Rhim, Ji-Won;Kwon, Young-Mann
    • Korean Membrane Journal
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    • 제1권1호
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    • pp.73-80
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    • 1999
  • The removal of trace chlorinated and aromatic hydrocarbons from water by a pervaporation technique has been carried out through poly (dimethylsiloxane) membrane which had been fabricated by the addition crosslinking reaction. This study dealt with the swelling and permeation behaviors of the PDMS membranes with dichloroethane trichloroethane and toluene aqueous solutions. The swelling ratio in the toluene aqueous solution was much higher than those in the chloroethane solutions at all of the operating temperatures and concentrations. The solubility parameter theory was introduced to interpret the affinity between permeates and a membrane material and in all cases this approach seemed to be proper. It was suggested that the existence of water clusters in the membrane due to the hydrophobic characteristics of the membrane made the size of the permeating water larger resulting in suppressing water permeation and increasing enrichment of the organic components. The permeation behaviors at different membrane thicknesses were indirectly interpreted in terms of the effect of concentration polarization.

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전사인쇄에 있어서 색재현에 관한 연구 (A Study on the Color Reproduction in Decalcomania)

  • 정다현;조가람;구철회
    • 한국인쇄학회지
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    • 제24권2호
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    • pp.35-48
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    • 2006
  • Textile decalcomania printing is how after the disperse dye which is melting and vaporizing absorbs on the surface of the cloth, it colors by permeating into the cloth inside. So it has applied a lot to the synthetic fiber like polyester. However, because there is no showing right temperature and time in case of printing on the polyester fiber and the microfiber, this study aims at it. The experimental methods are like this : first measuring the density for the objective judgment, and measuring colors with the colorimeter, and then study for the color reproduction through a visual evaluation.

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식재용 다공질 콘크리트의 개발에 관한 기초적 연구 (A Fundamental Study on the Development of Porous Concrete for Planting)

  • 윤기원;이상태;김기철;황정하;한천구
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1998년도 가을 학술발표대회 논문집(III)
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    • pp.912-915
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    • 1998
  • As a fundamental study on the development of porous concrete for planting, this study is designed to present the properties of porous concrete by varying the kinds of cement, paste to aggregate ratio and dosage of AE admixture. As the results of experiment, the void volumes show 30~33%, 25~ 28% and 17~22% respectively, with paste to aggregate ratio of 20%, 30% and 40%. And unit weight is 1700~1900kg/㎥ while compressive strengths 40~60, 8 0~100 and 120~150kg/$\textrm{cm}^2$. pH of concrete shows a sufficient value at which the plant could grow, when the concrete is permeated in Ammonium Phosphate Dibasic for more than 1 hour. In brief, it shows a possibility of development of porous concrete if the concrete is permeated with permeating in Ammonium Phosphate Dibasic for more than 1 hour when the blast furnace slag cement is used.

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Application of Molecular Simulation Techniques to Estimation of Gas Permeability in Zeolite Membranes

  • Takaba, Hiromitsu;Yamamoto, Atsushi;Nakao, Shin-Ichi
    • 한국막학회:학술대회논문집
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    • 한국막학회 2004년도 Proceedings of the second conference of aseanian membrane society
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    • pp.33-38
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    • 2004
  • Molecular modeling of gas permeation through zeolite membranes with/without intercrystalline region was carried out. Molecular dynamics (MD) and Monte Carlo (MC) simulations were performed to estimate the diffusion coefficient and adsorption parameters respectively, and our proposed combined method of molecular simulation techniques with a permeation theory (CMP) was used to estimate gas permeability. The calculated permeability of gases (Ar, He, Ne, $N_2$, $0_2$, $CH_4$) at 301 K for the single crystal membrane model was about one order of magnitude larger than the experiential values, although the dependence on the molecular weight of the permeating species agreed with experiments. On the other hand, the estimated permeability using the diffusivity and adsorption parameters of the intercrystalline region model was in good agreement with the experiments. The consistency between experiments and the estimated values means the importance of considering the intercrystalline region and the validity of CMP method to predict the performance of zeolite membranes.

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생활폐기물 소각장 작업복의 중금속 분석 (Analysis of Heavy Metal Concentration on Working Clothes for Waste Incinerating Workers)

  • 박순자
    • 한국지역사회생활과학회지
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    • 제18권1호
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    • pp.39-53
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    • 2007
  • The purpose of this study was to determine the characteristics of an experimental protective clothing material with regard to comfort and isolation from the hazardous heavy metals produced in municipal waste incineration. An analysis was conducted on the total concentrations of heavy metals in some parts such as surface, middle layer, and interior for the treated fabric, and the untreated one, and working clothes. We conclude that the processed fabric with charcoal for working clothes showed the least exposure to heavy metals of the three. Working clothes worn by workers during waste incineration were much more contaminated than the untreated and treated materials. The material of working clothes could be chosen according to the function with regard to its original chemical characteristics, which are the proper results of the dyeing process. The processed fabric material has high degrees of moisture regain, thermal insulation, water vapor penetration, and antibacterial function; consequently, it is much more comfortable to wear. The fabric material proposed in this research contributed much more to blocking heavy metal concentrations (such as Cd, Pb, Cu, Cr, Zn, Mn) than did the fabric of working clothes at present. Consequently, we strongly suggest that the material of working clothes be upgraded by adopting the above-mentioned charcoal-processed fabric. Materials of working clothes must be improved to increase comfort and prevent harmful gas, flying dust, and heavy metals from permeating the fabrics.

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