• 한국환경과학회지
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• 제12권7호
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• pp.791-799
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• 2003

This study was carried out to get more operational characteristics of the sequencing batch biofilm reactors with media volume/reactor volume ratio of 15 %, 25 % and 35 %. Experiments were conducted to find the effects of the media packing ratio on organic matters and nutrients removal. Three laboratory scale reactors were fed with synthetic wastewater. During studies, the operation mode was fixed. The organic removal efficiency didn't show large difference among three reactor of different packing media ratios. However, from the study results, the optimum packing media ratios for biological nutrient removal was shown as 25%. The denitrifying PAOs could take up and store phosphate using nitrate as electron acceptor.

• Mycobiology
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• 제39권2호
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• pp.125-128
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• 2011

Enzyme activities of Cenococcum geophilum isolates were examined on enzyme- specific solid media. Deoxyribonuclease, phosphatase, and urease were detected in all isolates, whereas cellulase was not detected in any of the isolates. Variations in enzyme activities of amylase, caseinolysis, gelatinase, lipase, and ribonuclease were observed among isolates.

• 한국환경과학회지
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• 제23권4호
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• pp.737-742
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• 2014

This study aimed for evaluating the applicability of the two stage dual media filtration system in field water treatment plant. The field plant of two stage and dual media filtration system was operated for 2 months. Average iron concentrations of the settled water, existing filtered water and second stage filtered water was 0.041 mg/L, 0.007 mg/L and 0.005 mg/L, respectively. Removal efficiency of iron concentration in the second stage is appropriately 35% more than in existing filtered water. Also removal efficiency of residual chlorine in the dual media filtration system is relatively 42.3% more than in existing filtered water due to adsorption of activated carbon, but the removal of ammonia nitrogen by adsorption is insufficient. Average concentrations of THM and chloroform in the settled water are 0.033 mg/L, 0.026 mg/L, respectively and in existing filtered water are 0.023 mg/L and 0.023 mg/L. Average concentrations of THM and chloroform in the dual media filtration system are 0.008 mg/L and 0.013 mg/L. Therefore removal efficiency of THM concentration in second stage is more than 66.4% in existing filtrated water. Also removal efficiency of chloroform in the dual media filtration system is more than 50.0% in existing filtered water because of the adsorption of activated carbon. In this case backwashing period in dual stage system is 4~5 days, but in existing filtration system is 1~2 days.

• 한국균학회지
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• 제27권1호통권88호
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• pp.15-19
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• 1999

배양실내에서 인공적으로 자실체의 형성을 유도한 결과 PDA와 번데기분말을 혼합한 배지상에서는 자실체의 형성을 유도할 수 없었다. 쌀을 이용한 곡물 배지에 수분함량을 달리하고 번데기를 첨가하여 시험을 실시한 결과 알락미에서는 곡물:수분함량이 1:3.5의 비율로 한배양기에서 가장 왕성한 자실체 생산을 보여 주었으며 현미의 경우는 곡물: 수분함량이 1:2.5로 조성된 배양기와 번데기를 첨가한 배양기에서 우수한 자실체 형성을 보여주었다. 자실체 형성적정 온도로는 $20^{\circ}C$가 적합한 것으로 밝혀졌다. 현미와 번데기를 첨가하며 조제한 배양기내에서 자실체형성을 유도한 결과 자실체 형성 우수균주로서 최종 C. militaris 25균주, C. scarabaeicola 2균주 등 27개 균주를 선발할 수 있었다. 현미와 누에번데기를 넣어 만든 배양기내에서의 자실체 형성은 약 50일내지 65일 사이에 완전한 형태의 자실체 형성을 볼 수 있었다.

• Membrane and Water Treatment
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• 제11권4호
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• pp.247-255
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• 2020

Sand filter is a key unit process for particle removal in water purification treatments. Its long-standing use is due to on-site customized retrofit. Proper selection of filter media is one of the retrofit approaches to improve filter performance. This study described a series of controlled laboratory column tests and examined the effects of media property on filtration and backwash. When sand media of 0.51 mm in effective size was replaced by sand of 0.60 mm, the filter run increased up to 5 times in the given bed depth. The change of media property required an increase of backwash rate by 0.05 m/min to satisfy the requirement of bed expansion, more than 20%. When the anthracite was changed with lower effective size and uniformity coefficient, correlation with sand in the filter bed could be satisfied within the permissible error between media and bulk characteristics. Besides, this selection resulted in a well-stratified configuration of media layers after bed expansion. The column study showed that the correlation of property between the dual media had a significant effect on the filter productivity and backwash interval.

• 한국지반환경공학회 논문집
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• 제4권2호
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• pp.93-104
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• 2003

Porous media consist of physically and chemically different materials and have an extremely complicated behavior due to the different material properties of each of its constituents. In addition, the internal structure of porous materials has generally a complex geometry that makes the description of its mechanical behavior quite complex. Thus, classical continuum mechanics cannot explain the behavior of materials with pore spaces, such as concrete, soils and organic materials in waste landfill. For these reasons, porous media theory has been developed in the nineteenth century. Biot had the greatest influence on the development of porous media theory. Biot's work has been referred by many authors in the literature. Development of numerous fundamental equations in porous media theory were made possible due to Biot's work. His contributions made the greatest influence on porous media theory. Therefore, it is highly advantageous to review Biot's publications. This work presents a review of Biot's work. It shows how porous media theory has been developing so far and provides a chance to discuss the contribution of his work to the modern porous media theory.

• Journal of the Korean Wood Science and Technology
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• 제45권6호
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• pp.857-871
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• 2017

The major substrates used in soilless growing media are peat moss and perlite, where peat moss is a limited and expensive natural resource. Determination of appropriate substrates based on technical and economic feasibility is the vital aspect of research and the key to success in any soilless production system. This research work was performed to evaluate different low-cost and sustainable alternative substrate as soilless growing media for horticulture plant. The objective of this study was to compare the effect of sawdust species and steam treatment, for physico-chemical properties and growth of horticultural plant. This study involves the physical and chemical characterization and growth test of four substrate (pine sawdust, oak sawdust, steamed pine sawdust and steamed oak sawdust) in order to evaluate their use as components of growing media. Steamed oak sawdust ($121^{\circ}C$, 30 min) showed adequate physical and chemical properties compared to peat moss for their use as growing media. The growing media were prepared using different mixture proportion to grow Brassica campestris L., Festuca arundinacea and Lespedeza cyrtobotrya Miq. The highest germination, stem length and leaf area of Brassica campestris L., Festuca arundinacea and Lespedeza cyrtobotrya were observed in 30 minute steamed oak sawdust mixture growing media. The steam treatment condition of sawdust used in the growing media significantly positive affected the germination, the stem length and the leaf area.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2005년도 INTERNATIONAL SYMPOSIUM ON SOIL & GROUNDWATER ENVIRONMENT
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• pp.197-198
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• 2005

• Bulletin of the Korean Chemical Society
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• 제32권10호
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• pp.3559-3560
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• 2011

• 환경기술인
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• 통권183호
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• pp.80-83
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• 2001