• 한국식품과학회지
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• 제13권2호
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• pp.91-100
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• 1981

두부폐수를 이용(利用)한 SCP생산(生産)의 기초 연구로서 유용(有用)효모의 검색(檢索), 최적배지선정 및 배양조건이 검토(檢討)되었다. 총 18종(種)의 효모중(中) 두부폐수를 가장 잘 이용(利用)하는 효모 C.utilis YUFE 1508과 C. guilliermondii KFCC 35120을 선정했으며 이들 효모의 최적생육(生育) pH는 $6.0{\sim}6.5$였고 최적배양온도는 $25^{\circ}C$였다. 탄소원으로서는 molasses 2.5%(전당기준), 질소원으로 ammonium acetate $0.1{\sim}0.3%$ (N함량기준), P 및 K원으로 $K_2HPO_4\;0.1{\sim}0.2%$ (P함량기준) 및 $K_2HPO_4$ 0.05% (P함량기준)를 두부폐수에 각각(各各) 첨가(添加) 함이 효모 생육(生育)에 가장 효과적(效果的)이었으며 금속염(金屬鹽)의 첨가는 생육(生育)에 아무런 영향을 미치지 못했다. 최적배양조건에서 48시간 배양했을때 최대(最大) 생육(生育)에 도달했으며 이때의 배양액 100ml의 건조균체중량은 C. utilis YUFE 1508이 1.313g, C. guilliermondii KFCC 35120의 경우가 1.322g이었다. 이를 대당(對糖)건조균 체수율로 환산하면 각각 68.4%, 74.2%였다. 또한 건조효모균체의 조단백질 함량은 C. utilis YUFE1508 이 약 54.0%, C. guilliermondii KFCC 35120의 경우가 56.8%정도였다.

• 유기물자원화
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• 제22권3호
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• pp.23-32
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• 2014

최근 들어 유기성폐기물의 혐기소화를 이용한 처리(에너지화)가 증가하고 있다. 이에 따라서 혐기소화 후 발생하는 혐기소화폐액의 처리방안에 대한 연구도 증가하고 있다. 그러나, 혐기소화폐액의 특성상 문제로 고액분리에 매우 어려움이 있다.이에 본 연구에서는 CST와 TTF를 이용하여 혐기소화폐액에 대한 응집에 따른 고액분리 특성을 파악하였다. 또한 이러한 문제를 해결하기 위하여 실험실수준의 멤브레인 필터프레스를 제작하고, 혐기소화폐액에 적용하였다. 고분자 응집제는 7192PLUS와 1T60가 가장 적합한 것으로 확인되었으며, 최소 7192PLUS (200 mg/L), 1T60 (100 mg/L)이상의 투입이 필요하였다. 탈수효율을 평가하기 위하여 탈수케이크의 함수율과 탈리여액의 입자성 고형물을 이용하였다. 결과적으로, 멤브레인 필터프스를 이용하여 고액분리 시 입자성 고형물의 제거효율은 97.4%로 높게 나타났으며, 탈수케이크의 함수율은 65%이하로 나타났다.

• 한국토양비료학회지
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• 제20권2호
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• pp.123-129
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• 1987

수도(水稻)의 축산폐수(畜産廢水) 피해(被害)에 대한 물관리(管理) 및 개량제(改良劑) 시용효과(施用效果)를 구명(究明)하기 위하여 사양토(砂壤土)에서 2년간(年間) pot 시험(試驗)한 결과(結果)는 다음과 같다. <시험(試驗) 1> 물관리(管理) 및 개량제(改良劑) 시용효과(施用效果)(1985) 1. 수도수량(水稻收量)은 상시담수구(常時湛水區)가 간단관수구(間斷灌水區) 보다 많다고 개량제(改良劑) 시용(施用)으로 증수(增收)되는 경향(傾向)이였으며 개량제중(改良劑中) Zeolite와 규회석(硅灰石)이 효과(效果)가 좋았음. 2. 고중(藁重) 및 식물체중(植物體中) 질소함량(窒素含量)은 시용질소(施用窒素) 및 폐수관개량(廢水灌漑量)이 많을수록 증가(增加)하였으나 개량제(改良劑) 시용(施用)으로 감소(減少) 하였음. <시험(試驗) 2> 규회석(硅灰石) 시용효과(施用效果)(1986) 3. 수도수량(水稻收量)은 규회석(硅灰石) 시용량(施用量)이 증가(增加)할수록 증수(增收)되었으며 규회석시용(硅灰石施用)에 의(依)한 증수원인(增收原因)은 등숙율(登熟率) 및 수당입수(穗當粒數)의 증가(增加)에 있었고 질소시용량(窒素施用量)이 3g/pot (관행(慣行))구(區)에서는 규회석(硅灰石) 60g/pot 시용(施用)이 적량(適量)으로 생각되었다. 4. 불임수수(不稔穗數)는 시용질소(施用窒素) 및 폐수중(廢水中) 질소농도(窒素濃度)가 증가(增加)됨에 따라 증가(增加)하는 경향(傾向)이었으며 규회석시용(硅灰石施用)으로 크게 감소(減少)되었다.

• Environmental Engineering Research
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• 제12권1호
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• pp.30-35
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• 2007

Fenton system using homogeneous iron catalyst is very powerful in the degradation of organic compounds, but has a disadvantage to remove Fe ions from water after wastewater treatment. Thus, iron catalyst was bounded to support such as inorganic and polymer materials. The PVP supporting iron catalyst showed a good catalytic performance in degradation of phenol contained in waste water and iron catalyst supported on ${SO_4}^{2-}$ type PVP (KEX 511) showed the best catalytic performance. Also, reaction kinetic study was carried out in this system. Reaction constants on various catalysts was obtained from the pseudo first order equation. Reaction rate constants with the heterogenized $FeCl_2/PVP$ catalyst is a three-fold smaller than that of $FeCl_2$ catalyst.

• International Journal of Concrete Structures and Materials
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• 제8권2호
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• pp.165-172
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• 2014

Recycled coarse aggregate (RCA) made from waste concrete is not a suitable structural material as it has high absorption of cement mortar, which adheres on the aggregate surface and on the tiny cracks thereon. Therefore, when using RCA made from waste concrete, much water must be added with the concrete, and slump loss occurs when transporting. Hence, its workability is significantly worse than that of other materials. In this study, surface of RCA was coated with water-soluble polycarboxylate (PC) dispersant so that its characteristics improved. Each possibility was evaluated: whether its slump loss can be controlled, by measuring its workability based on the elapsed time; and whether it can be used as a structural material, by measuring its strength. Moreover, the carbonation due to cement mortar adhesion was measured through a carbonation test. As a result, RCA coated with PC dispersant was found to be better than crushed coarse aggregate and RCA when the physical properties of the fresh concrete and the mechanical, durability of the hardened concrete were tested.

• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2010년도 학술논문요약집
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• pp.271-272
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• 2010

Sensitivity analysis by TSUNAMI clarifies the complex effects of key nuclides on the criticality probability quantitatively. As discussed above, the $K_{eff}$ of $UO_2$ fuel reaches the maximum value with 42w% concentration of intrusion water. The concentration of hydrogen affects the complexity of reaching criticality by its competition between the concentrations of $^{235}U$. Approximately if the weight percent of $H_2O$ in the mixture is less than 42%, the moderation effect of hydrogen surpasses its dilution effect on $^{235}U$. However, the importance of $^{235}U$ increases dramatically when the weight percent of water is bigger than 42%. In the sensitivity evaluation of $UO_2$ fuel employing TSUMAMI, there is a similar crosspoint of the sensitivity of $^{235}U$ and the sensitivity of $^1H$ where the criticality reaches summit. And the optimal water weight percent is determined to be 50%.

• 한국염색가공학회지
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• 제4권3호
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• pp.131-135
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• 1992

Quaternary aminized cellulosic adsorbents (C $A_{QA}$ ) which exhibit adsorption capacities for anionic dyestuffs for the treatment of colored waste water and re-use of the treated water were studied. The isotherms and thermodynamic parameters of C.I. Acid Orange 7, solution considered as a model of negatively charged coloring matters for C $A_{QA}$ , were determined. Batch method and flow method were employed to determine decoloring capacity of cellulosic adsorbents for Orange 7. The cellulosic adsorbents exhibited much better adsorption capacity than activated carbon. Furthermore the exhausted cellulosic adsorbents could be readily regenerated by washing with dilute sodium hydroxide.

• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2004년도 Proceedings of the 4th Korea-China Joint Workshop on Nuclear Waste Management
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• pp.42-50
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• 2004

The pool $(3m{\times}6m{\times}10m{\times}$ in Irradiated Materials Examination Facility is generally used to transport irradiated materials between a moving cask and hot-cell. During the operation in the pool such as loading/unloading the cask, holding specimen and bucket elevation, water maybe contaminated by radioactive or contaminated impurities from irradiated materials. Then, it must be purified and filtered continuously to keep lower radioactivity than that of regulation prescribed by RCA Korea Activity in a part of radioactive contamination control. This paper described radioactive contamination distribution of water as transported materials, which is related to effective operation of purification and filtration system.

• 한국환경과학회지
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• 제12권1호
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• pp.41-45
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• 2003

Magnetite powder for kerosene-based ferrofluid was synthesized by air oxidation of waste acid containing $Fe^{2+}$ and $Fe^{3+}$ ions in the pH=11 at $60^{\circ}C$. Stable kerosen-based ferrofluid was prepared by addition of polyoxyethylene nonylphenyl ether(POENPE) to the magnetite containing water. Dispersion mechanism of an addition POENPE to the magnetite was examined by means of the fraction of solid dispersed FT-IR spectrum. And magnetic properties of kerosen-based ferrofluid were examined by method of Vibrating Sample Magnetometer. In order to remove oil on the water surface by an addition of kerosen-based ferrofluid, the optimum conditions were examined.

• Nuclear Engineering and Technology
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• 제33권2호
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• pp.156-165
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• 2001

A radiological safety assessment was performed for a hypothetical near-surface radioactive waste repository as a simple screening calculation to identify important nuclides and to provide insights on the data needs for a successful demonstration of compliance. Individual effective doses were calculated for a conservative ground water pathway scenario considering well drilling near the site boundary. Sensitivity of resulting ingestion dose to input parameter values was also analyzed using Monte Carlo sampling. Considering peak dose rate and assessment time scale, C-14 and T-129 were identified as important nuclides and U-235 and U-238 as potentially important nuclides. For C-14, the dose was most sensitive to Darcy velocity in aquifer The distribution coefficient showed high degree of sensitivity for I-129 release.