• 한국토양비료학회지
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• 제15권4호
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• pp.207-212
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• 1982

1950년대(年代)의 핵실험(核實驗)에 의(依)하여 생긴 방사능(放射能) 동위원소(同位元素)는 토양(土壤)이나 퇴사(堆砂)에 다양(多樣)하게 포함(包含)되었다. 이들 방사성(放射性) 동위원소(同位元素) 중(中)에서 $^{137}Cs$은 미세토양(微細土壤) 입자(粒子)에 고착(固着)하는 성질(性質)이 크고 방사능(放射能)의 발산량이 많고 균일(均一)하기 때문에 퇴사과정(堆砂過程)을 평가하는데 이용(利用)이 가능(可能)하다. 미국 Louisiana 주(州) Larto호(湖)에서, 낙진(落塵)된 $^{137}Cs$에 의(依)해 1958년(年) 이내로 퇴사속도(堆砂速度)를 측정(測定)한 바에 의(依)하면 연평균(年平均) 1.6~3.1cm로 퇴사(堆砂)되고 있으며, 가장 많이 퇴사(堆砂)된 곳은 70cm까지 퇴사(堆砂)되었음이 밝혀졌다. 또한 해를 거듭할수록 퇴사(堆砂)되는 율(率)이 적어지고 있으며, 퇴사(堆砂)의 입도분포(粒度分布)는 호수(湖水) 전체에 거의 $20{\mu}$이하(以下)의 미세입자(微細粒子)가 분포(分布)하고 있었다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제15권2호
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• pp.47-54
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• 2010

Although the demands for the dredging work have been increasing due to social and industrial reasons including national plan for restoration of four major rivers, environmental standards or management guidelines for the dredged river sediment are limited. The suggested environmental standard for the beneficial use of dredged river sediment consists of two levels, recyclable and concern, and includes eight contaminants such as metals and organic contaminants. The systematic approach to remediate dredged river sediment is also suggested. The system consists of both washing and stabilization processes with continuous multi particle separation. In the early stage, the sediments are separated into two particle sizes. The coarse-grained sediment over 0.075 mm, generally decontaminated with less trouble, follows normal washing steps and is sent for recycling. The fine-grained sediments under 0.075 mm are separated again at 0.025 mm. The particles bigger than this second separation point are treated in two ways, advanced washing for highly contaminated sediments and stabilization for less. The lab test results show that birnessite and apatite are most effective stabilizing agents among tested for Cd and Pb. The most fine residues, down-sized by continuous particle separation, are finally sent for disposal. The system is tested for metals in this study, but is expected to be effective for organic contaminants included in the environmental standard, such as PAH and PCE. The feasibility test on the field site will be followed.

• Animal cells and systems
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• 제8권Supplyment
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• pp.28-28
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• 2004

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2003년도 학술발표회논문집(2)
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• pp.659-662
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• 2003

• 한국물환경학회지
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• 제37권4호
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• pp.286-295
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• 2021

The removal efficiency of road-deposited sediment (SDR) by road sweeping was analyzed by performing particle size analysis before and after road sweeping at four highways during May to December 2019. The SDR accounted for the largest proportion in the range of 250 to 850 ㎛ and the degree of its proportion had an effect on the particle size distribution curve. The particle size distribution of the collected sediments showed a similar distribution at all sites. Below 75 ㎛, the removal efficiency of SDR showed a constant value around 40%, but above 75 ㎛, it increased as the particle size increased. The removal efficiency was 82-90% (average 86%) for gravel, 66-93% (average 79%) for coarse sand, 35-92% (average 64%) for fine sand, 29-69% (average 44%) for very fine sand, 19-58% (average 40%) for silt loading, 10-59% (average 40%) for TSP, 13-57% (average 40%) for PM10, and 15-61% (average 38%) for PM2.5. SDR removal efficiency showed an average of 69% for the four highways. It was found that if the amount of SDR was less than 100 g/m², it was affected by the road surface condition and had a large regional deviation. As such, the amount of SDR and the removal efficiency increased. The fine particles, which have relatively low removal efficiency, contained a large amount of pollutants, which is an important factor in water and air pollution. Therefore, various measures to improve the removal efficiency of fine particles in SDR by road sweeping are needed.

• 한국수처리학회지
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• 제26권6호
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• pp.43-51
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• 2018

In order to systematically and scientifically manage the organic and heavy metals against sediment at Daecheon Port, this study conducted particle composition, organic materials and heavy metals irradiation studies of sediments. Analysis of the grain size composition of sediments in the target study area showed the distribution characteristics of the mix of sand, silt and clay. That is, Station C (Stn. C) showed superior by fine-grained sediment, Station A and B (Stn. A and B) showed superior by coarse-grained sediment. The organic matter(COD, TOC, and IL) of Stn. C was appeared to be heavily polluted more than Stn. A and B. These data for the spatial properties in sediment showed that organic matter was related positively to the sediment silt-clay content. Also, in the case of heavy metals contamination in surface sediments, Stn. C was higher than Stn. A and B. Particularly, at the Stn. C, high organic matter concentration and C/N ratio value( >10) indicated that the sediment was composed highly of land-derived organic matter. From these results, it considered that the correlation analysis among to silt-clay, organic matter and heavy metal was found to have a good interrelationship.

• 한국지형학회지
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• 제26권4호
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• pp.1-20
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• 2019

In order to establish appropriate policy to control sediment-associated problems, it is necessary to identify the physical characteristics of the reservoir sediments in particulate form in the Yeongsan River. Two time-integrated suspended sediment samplers were installed at Seungchon and Juksan weir on the upper and middle Yeongsan River in July 2012. Reservoir sediment samples were obtained at monthly intervals until October 2014. During the monitoring period, a total of 38 sediment samples were obtained and analyzed. Seasonal trends of suspended sedimentation rates and grain size distributions were examined based on variations in precipitation and discharge fluctuations. Moreover, stream flow characteristics, which has a great influence on the physical characteristics of the river sediment, was analyzed using flow duration curve for the period 2003-2019 at Naju gauging station. Sedimentation rates during summer, when heavy rainfall was concentrated due to the monsoonal front and typhoon, were very high, indicating the positive relationship between sediment concentration and discharge. Particle size analysis of the collected sediment showed that coarse silt and very fine sand-sized sediment dominated most of the Seungchon weir sediment. On the other hand, medium silt-sized sediment dominated the downstream Juksan weir except for a few summer samples. These results implied that the physical characteristics of the suspended sediment are determined not only due to flow fluctuations, but also with regard to the antecedent rainfall conditions, hillslope-channel connectivity, and the supply of materials from various contributing regions. This information about flow characteristics and temporal variations in reservoir sediment can be used for safe management of the weir and discussing the issues on the dismantling of the weirs.

• 한국해양학회지
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• 제22권1호
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• pp.25-33
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• 1987

河口와 인접한 內 에서 海流에 의한 微細粒 堆積物質의 輸送, 擴散現象을 數値的으로 分析하였다. 사용된 모델은 水理實驗과 現場觀測의 최근 硏究結果를 근거로 開發되었으며 堆積物의 浮上, 堆積, 輸送過程을 보다 실제 상황에 근접하도 록 數値, 計算하였다. 江의 흐름과 潮汐에 의한 海水流動, 이에 따른 沿岸海域에서의 浮遊物質 濃度, 海底寢食 그리고 堆積分布에 대한 時間別 變化를 計算하였다. 初期 에는 浮上된 堆積物에 의해 浮遊物質의 濃度가 크게 增加되었으나, 時間이 경과됨 에 따라 外海로 輸送되어 江河口에서는 濃度가 크게 줄어들었다. 河口隣接 內 의 海底 堆積物의 寢食과 堆積狀態는 內 의 地形的 條件에 따른 海流의 流速分布와 堆積物 特性에 의해 주로 決定됨을 나타내었다.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2022년도 추계학술대회
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• pp.316-316
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• 2022

Azuki bean is the important bean crop in Korea, and is traditionally used as a filling material for red bean porridge, rice cakes, and bread, as well as for sediment. So far, the National Insititute of Crop Science has developed azuki bean varieties for various uses, such as for sediment, tea, and azuki bean sprouts. Among azuki bean elite lines, 25 strains were used to analyze the correlation between red bean quality characteristics and sediment yield. The crude protein of red beans was 25.0-28.9%, ash content was 3.8-5.3%, and fat was 0.4-1.0%. As for the appearance quality characteristics of azuki bean, one hundred seed weight was 11.1-19.5 g, the length of seed was 6.45-8.49 mm, the width seed was 4.84-6.45 mm, and the withd/lenght ratio was 0.72-0.89. When the azuki bean were boiled, the thickness of the seed coat was 0.14-0.27 mm and the length ratio of seed was 0.65-0.76 mm, showing that the length of seed was slightly larger than the width. The yield of azuki bean sediment was 239-284% for whole red bean paste, and 144-203% for fine azuki bean paste. As a result of analyzing the correlation between the quality characteristics of azuki beans, such as protein, husk and seed weight, and the yield of azuki bean sediment, the yield of whole azuki bean sediment showed a negative correlation with the seed coat thickness and the length ratio of the original grain at -0.62 and -0.45, respectively. The yield of fine sediment showed a negative correlation with the length ratio of whole azuki beans at -0.49, and a positive correlation with that of white beans at 0.41. However, protein and ash content did not show any correlation with sediment yield. In view of the above results, it is thought that it would be better to have a high seed weight or a low width/length ratio of seed to develope azuki bean cultivar for sediment.

• 한국물환경학회지
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• 제28권2호
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• pp.232-237
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• 2012

Total suspended solids (TSS), settleable suspended solids (SSS) and nonsettleable suspended solids (NSSS) were compared in streams and lakes during rain events. Samples were collected in Lake Soyang and nine agricultural streams during storm events over two years. To measure NSSS, samples were settled in 1 L cylinders for one hour and then 50% of the total sample volume was taken from the center of the cylinder. The SSS/TSS ratio in streams (0.50) was higher than in Lake Soyang (0.20). The ratio of TSS to turbidity decreased from 1.21 in the inflowing river to 0.69 in the reservoir outlet. Turbidity and NSSS showed higher correlation ($r^2$=0.82) compared with the correlation between turbidity and TSS ($r^2$=0.66). Median particle size decreased from $11.4\;{\mu}m$ in the inflowing river to $4.2\;{\mu}m$ in the lake outlet. The results indicate that only fine particles of less than $5{\sim}10\;{\mu}m$ can be transported downstream of the lake. Because fast-flowing water in streams includes not only fine particles but also coarse particles, an overestimation of suspended sediment concentration results if only TSS is measured. Consequently, TSS and NSSS should be measured separately to evaluate the effect of suspend sediment loadings of turbid streams on aquatic habitat during the monsoon season.