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        41.
        2014.09 KCI 등재 서비스 종료(열람 제한)
        In this study, as a fundamental study for the remediation of the radionuclides-contaminated soil, the adsorption of cobalt, strontium, and cesium on natural soil and kaolin were experimently investigated and adsorption characteristics were evaluated by using several adsorption kinetic and isotherm models. The pseudo-first-order kinetic model (PFOM), pseudo-second-order kinetic model (PSOM), one-site mass transfer model (OSMTM), and two compartment first-order kinetic model (TCFOKM) were used to evaluate the kinetic data and the pseudo-second-order kinetic model was the best with good correlation. The adsorption equilibria of cobalt, strontium, and cesium on natural soil were fitted successfully by Redlich-Peterson and Sips models. For kaolin, the adsorption equilibria of cobalt, strontium, and cesium were fitted well by Redlich-Peterson, Freundlich, and Sips models, respectively. The amount of adsorbed radionuclides on natural soil and kaolin was in the order of cesium > strontium > cobalt. It is considered that these results could be useful to predicting the adsorption behaviors of radionuclides such as cobalt, strontium, and cesium in soil environments.
        43.
        2011.09 서비스 종료(열람 제한)
        양식 종묘생산 현장에서 발생하는 기형 중에는 척추 기형 발생빈도가 매우 높은 것으로 알려져있으나, 초기 발생과정 동안에는 육안적 관찰이 매우 어려울 뿐만 아니라, 사육환경의 여러 가지 요인에 따라 기형의 양상도 달라지므로 (Vågsholm and Djupvik, 1998) 정확한 발생원인 분석이 어려운 실정이다. 기형의 형태적 검사법은 주로 morphometry을 이용하여 외부형태의 수리적 해석을 접목한 분석기법 (Bookstein, 1997; Kawamura and Hosoya, 1997), X-ray 촬영에 의한 골영상 분석기법 또는 bone & cartilage double stain 기법 (Park and Kim, 1984) 그리고 추체의 구조적 특징을 분석하는 골형태학적 분석 기법 (Witten et al., 2009) 등이 주로 이용되고 있다. 이 중 골형태학적 분석기법은 직접적으로 뼈를 관찰하기 때문에 기형 증상 판별에 있어 가장 높은 신뢰성을 보이는 것으로 알려져 있다. 따라서 본 연구에서는 우리나라 대표적 양식대상종인 돌돔 성어 (1년생 이상, n=40)와 미성어 (1년생 이하, n=28)를 대상으로 X-ray에 의한 분석, 정상어와 척추기형어 간의 외부형태 비교분석을 통하여 기형어 판별방법으로서의 이용가능성을 알아보고, 골형태학적 분석 기법을 통하여 추체변형 타입을 정확히 판별함과 동시에 돌돔의 기형 판별에 대한 기준을 제시하고자 하였다. X-ray 사진촬영에 의한 분석 결과, 돌돔 성어 및 미성어에서 조사된 척추기형 중 전만증 발생비율은 각각 67.5%, 21.4%로 조사되었으며, 단구증 (vertebral compression)의 경우 각각 32.5%, 14.3%로 조사되어 다른 척추기형 증상에 비해 높게 나타났다. X-ray 판독에 의해 분류된 정상어와 척추기형어간의 외부형태 비교에서는 성어의 경우, (체장-두장)/두장값과 체고/두장값이 유의적 차이를 보였지만, 미성어의 경우 두 그룹 간에 차이가 없는 것으로 조사되었다. 이 같은 결과는 기형어 내에서도 개체간의 척추변이의 정도 (服部, 2004)나 가계 간에도 외부형질이 변화한다는 보고(谷口 등, 1995)에 비추어 볼 때 기형판별의 기준점으로 제시하기는 어려울 것으로 생각된다. 양식산 돌돔의 성어 및 미성어에서 골형태학적 분석 기법으로 조사한 결과, 추체의 경우 압착 및 유합, 비대칭, 탈구 그리고 추체 사이의 비정상적 간격이 조사되었고, 전체적인 척추의 형태는 전만증, 후만증 그리고 복합적인 척추 기형 증상을 보였다. 본 연구에서는 돌돔을 대상으로 추체 기형판별을 위한 기초조사로서 상업적 양식장 한곳만을 대상으로 조사하였다. 그러나 추체의 변형을 유발하는 여러 가지 직․간접적인 사육환경 요인들이 보고되고 있고 (Kvellestad et al., 2000; Madsen et al., 2001; Hattori et al, 2004; Aunsmo et al., 2008), 추체변형의 종류는 어종별로 차이를 보이기 때문에 (Favaloro and Mazzola, 2000; Boglione et al., 2001; Lewis et al., 2004; Witten et al, 2009), 각 지역에 위치한 양식장을 대상으로 장기적이고 체계적인 조사가 필요할 것으로 생각된다.
        44.
        2009.12 KCI 등재 서비스 종료(열람 제한)
        속성장 육종 넙치(selected line of olive flounder cultured, SF)의 수정란의 부화율 및 기형률, 자치어의 성장을 일반 넙치(unselected line of olive flounder cultured, UF)와 비교하였다. 동일한 날에 획득한 SF구 및 UF구 수정란의 부화율은 SF구가 96.21.7%, UF구는 90.42.1%로 SF구가 높았으며, 기형률은 UF가 유의하게 높았다. 이들 수정란으로부터 부화한 자어를 8
        45.
        2009.06 KCI 등재 서비스 종료(열람 제한)
        Lab-scale Electrodialysis(ED) system with different membranes combined with before or after pyroma process were carried out to remove nitrate from two pickling acid wastewater containing high concentrations of NO3-(≈150,000 mg/L) and F-(≈160,000 mg/L) and some heavy metals(Fe, Ti, and Cr). The ED system before Pyroma process(Sample A) was not successful in NO3- removal due to cation membrane fouling by the heavy metals, whereas, in the ED system after Pyroma process(Sample B), about 98% of nitrate was removed because of relatively low NO3- concentration (about 30,000 mg/L) and no heavy metals. Mono-selective membranes(CIMS/ACS) in ED system have no selectivity for nitrate compared to divalent-selective membranes(CMX/AMX). The operation time for nitrate removal time decreased with increasing the applied voltage from 10V to 15V with no difference in the nitrate removal rate between both voltages. Nitrate adsorption of a strong-base anion exchange resin of Cl- type was also conducted. The Freundlich model(R2 > 0.996) was fitted better than Langmuir model(R2 > 0.984) to the adsorption data. The maximum adsorption capacity (Q0) was 492 mg/g for Sample A and 111 mg/g for Sample B due to the difference in initial nitrate concentrations between the two wastewater samples. In the regeneration of ion exchange resins, the nitrate removal rate in the pickling acid wastewater decreased as the adsorption step was repeated because certain amount of adsorbed NO3- remained in the resins in spite of several desorption steps for regeneration. In conclusion, the optimum system configuration to treat pickling acid wastewater from stainless-steel industry is the multi-processes of the Pyroma-Electrodialysis-Ion exchange.
        48.
        2004.09 KCI 등재 서비스 종료(열람 제한)
        This study evaluated the technical feasibility of the application of TiO2 photocatalysis for the removal of volatile hydrocarbons(VHC) at low ppb concentrations commonly associated with non-occupational indoor air quality issues. A series of experiments was conducted to evaluate five parameters (relative humidity (RH), hydraulic diameter (HD), feeding type (FT) of VHC, photocatalytic oxidation (PCO) reactor material (RM), and inlet port size (IPS) of PCO reactor) for the PCO destruction efficiencies of the selected target VHC. None of the target VHC presented significant dependence on the RH, which are inconsistent with a certain previous study that reported that under conditions of low humidity and a ppm toluene inlet level, there was a drop in the PCO efficiency with decreasing humidity. However, it is noted that the four parameters (HD, RM, FT and IPS) should be considered for better VHC removal efficiencies for the application of TiO2 photocatalytic technology for cleansing non-occupational indoor air. The PCO destruction of VHC at concentrations associated with non-occupational indoor air quality issues can be up to nearly 100%. The amount of CO generated during PCO were a negligible addition to the indoor CO levels. These abilities can make the PCO reactor an important tool in the effort to improve non-occupational indoor air quality.
        49.
        1998.10 KCI 등재 서비스 종료(열람 제한)
        Poly(DADM) was synthesized for the drinking water treatment. Poly(DADM) was produced by the free radical polymerization of diallyldimethylammonium chloride(DADM) monomer and its properties were characterized. The effects of monomer concentration, initiator concentration and reaction time on synthesis of poly(DADM) were investigated. Poly(DADM) flocculant was applied to Nak-dong river water to examine its efficiency in reducing turbidity. The synthesized poly(DADM) was effective as flocculant for drinking water treatment. The addition of 1 ㎎/L.of poly(DADM) flocculant caused the reduction of 50 % PAC(polyaluminium chloride).
        50.
        1998.06 KCI 등재 서비스 종료(열람 제한)
        Polyamine was synthesized for the drinking water treatment. Polyamine was produced by the two step polycondensation of dimethylamine(DMA) and epichlorohydrin(EPI) and its properties were characterized. The effects of mole ratio of [DMA]/[EPI], reaction temperature and reaction time on synthesis of polyamine were investigated. Polyamine flocculant was applied to Nak-dong river raw water to examine its efficiency in reducing turbidity. The synthesized polyamine was effective as flocculant for drinking water treatment. The addition of 1 ㎎/L of polyamine flocculant caused the reduction of 50% PAC (polyaluminium chloride).
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