• 한국환경보건학회:학술대회논문집
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• 한국환경보건학회 2001년도 Proceedings of the 3rd Annual Meeting of Yellow Sea Environment
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• pp.6-10
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• 2001

Distribution characteristics, variation patterns and affecting factors of hetorotrophic bacteria were studied from April to May 1999 in Bohai Sea by standard Acridine Orange epifluorescence microscopy (AO method). The biomass in surface waters showed a small day-night variation, varying from 0.13-2.51$\mu\textrm{m}$$.$dm$\^$-3/ with an average of 0.84 $\mu\textrm{m}$$.$dm$\^$-3/. The biomass in bottom waters showed, however, a large variation, changing from 0.15-4.18 $\mu\textrm{m}$$.$dm$\^$-3/ with an average of 1.36 $\mu\textrm{m}$$.$dm$\^$-3/. The peak values were obtained at 5 and 11 am. The bottom water biomass showed a significant correlation with particulate organic carbon (r=0.639, p<0.05). Heterotrophic bacteria showed high biomass in nearshore waters and low values in offshore areas with a high biomass zone around Yellow Sea river mouth, which was consistent with the distribution of nutrients. The vertical distribution of heterotrophic bacteria showed biomass in bottom waters was higher than in surface water. The biomass of heterotrophic bacteria in Bohai Sea was similar with that in other marine waters.

• KSBB Journal
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• 제16권4호
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• pp.351-355
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• 2001

호흡율 측정법을 이용하여 하수의 유기물 성분을 ASM No.1에서 제안한 네 가지 성분으로 구분하였다. Ss의 경우 전체 TCOD의 10-16%, Xs의 경우 32-50%, S$_1$의 경우 8-1% 정도를 차지하는 것으로 나타났으며, X$_1$의 경우 2-47% 정도를 차지하는 것으로 관찰되었다. 그리고 이 결과는 외국의 결과와 비교해 볼 때 Ss 성분이 10% 작을 반면 X$_1$ 성분은 10% 정도 큰 것으로 비교되었다. 하수의 미생물 농도를 분석한 결과, active heterotrophic biomass가 TCOD의 10-23% 정도를 차지하고 있었으며, active autotrophic biomass는 검출되지 않았다. 본 실험은 현재 TCOD, SCOD로 구분하는 하수의 유기물 성분을 미생물의 이용 정도를 나타내는 호흡률 측정법으로 세분화함으로서, 본 실험 방법을 이용하여 유기물 분해 과정 및 탈질화 그리고 인 제거 기작에 사용되는 유기물에 대한 정보를 구체적으로 제공할 수 있음을 보여 주었다.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2019년도 추계 학술논문 발표대회
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• pp.21-22
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• 2019

In order to prevent global warming according to fossil fuel use, countries around the world are making efforts through the Kyoto Protocol and the Paris Climate Change Convention. In addition, in order to prepare for high oil prices, researches such as the development of various renewable energy are being conducted. At present, the domestic production rate of energy sources in Korea is low at 18.1%, and power plants using forest biomass are being constructed to meet the domestic situation where 63% of the land is a forest. In 2015, the global production of wood pellets, a raw material for wood-based biomass power generation, was 28 million tons, up 7.7% from 2014, and has increased tenfold over the last decade. This is a result of increased demand for biomass. Korea is also increasing every year. However, biomass fly ash, an industrial by-product generated by biomass energy generation, is now being disposed of entirely, and there is little research to utilize it. Therefore, this paper will use biomass fly ash, an industrial by-product, which is currently being discarded due to a lack of separate treatment methods, as an admixture concept to contribute to solving environmental problems, developing new admixtures, improving quality, and seeking recycling plans.

• Environmental Engineering Research
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• 제23권4호
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• pp.449-455
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• 2018

In this study, the contribution of hot biomass ash to enrichment of the mineral content and to reducing the moisture content of broiler poultry manure was investigated. For this purpose, the mixtures have been prepared by adding biomass ash at varying rates (10%, 20%, 30%, 40% and 50%) and at different temperatures ($100^{\circ}C$, $150^{\circ}C$, $200^{\circ}C$ and $250^{\circ}C$) according to the dry matter content (74.77%) of the poultry manure. The results showed that incorporation of biomass ash into poultry manure at 50% at $250^{\circ}C$ reduced the moisture content from 25.23% to 9.82%. Regarding the maximum N in the final product, the ideal temperature of biomass ash has been obtained at $150^{\circ}C$. The highest nutrient contents were obtained at 50% biomass ash incorporation. The highest dose of biomass ash application had significantly increased nutrients, such as Ca (19.34%), K (4.03%), Fe (1,545 mg/kg), Mn (812 mg/kg) and Zn (479 mg/kg) in the final organomineral fertiliser formulation. Overall, it was concluded that the addition of hot biomass ash can dramatically decrease the moisture content of poultry manure and therefore provide odour and pathogen removal and increase its plant nutrient content.

• 한국수소및신에너지학회논문집
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• 제30권1호
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• pp.49-57
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• 2019

Biomass, a carbon-neutral fuel, has great advantages because it can replace fossil fuels to reduce greenhouse gas emissions. However, due to its low density, high water content, and hydrophilicity, biomass has disadvantages for transportation and storage. To improve these properties, a pretreatment process of biomass is required. One of the various pre-treatment technologies, torrefacion, makes biomass similar to coal through low-temperature pyrolysis. In this study, torrefacion treatment was carried out at 200, 230, 250, 280, and $300^{\circ}C$ for wood pellet, empty fruit bunch (EFB) and kenaf, and the feasibility of replacing coal with fuel was examined. Hygroscopicity tests were conducted to analyze the hydrophobicity of biomass, and its chemical structure changes were investigated using Infrared spectrum analysis. It was confirmed that the hygroscopicity was decreased gradually as the torrefacion temperature increased according to the hygroscopicity tests. The hydrophilicity was reduced according to the pyrolysis of hemicellulose, cellulose, and lignin of biomass.

• 신재생에너지
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• 제19권1호
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• pp.12-21
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• 2023

Governments and global companies are working towards using renewable sources of energy, such as solar, wind, and biomass, to reduce dependency on fossil fuels. In the defense sector, the new strategy seeks to increase the sustainable use of renewable energy sources to improve energy security and reduce military transportation. Renewable energy technologies are affected by factors such as climate, resources, and policy environments. Therefore, governments and global companies need to carefully select the optimal renewable energy sources and deployment strategies. Biomass is a promising energy source owing to its high energy density and ease of collection and harvesting. Many techniques have been developed to convert the biomass into electrical energy. Recently, diverse types of fuel cells have been suggested that can directly convert the chemical energy of biomass into electrical energy. The recently developed biomass flow fuel cell has significantly enhanced the power density several hundred times, reaching to ~100 mW/cm². In this review, we explore various strategies for producing electrical energy from biomass using modern methods, and discuss the challenges and potential prospects of this method.

• 수산해양기술연구
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• 제38권1호
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• pp.1-10
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• 2002

1. 제주해협에서는 6월에 가장 낮은 생물량 분포를 나타내었고, 가을철(11월)에 가장 높은 생물량 분포를 보이면서 높은 2차 생산력을 보이는 것으로 사료된다. 2. 해황 및 습중량과의 관계에서 가장 높은 분포를 나타내는 정점은 각각 정점 14와 11로 그 출현위치는 해협의 중앙부분이고, 한국남해연안역 및 제주도 북부연안역에는 다소 낮은 생물량분포를 보이고 있으며, 생물량 분포가 높게 나타나는 해역의 특징은 patch의 형태로 분포하였다 반면 한국남해연안역에 비하여 제주도 북부연안역에높은 생물량 분포를 나타냄으로써 제주해협에서의 갈치어장 형성위치와 생물량 분포와의 관계가 밀접하게 나타날 것으로 판단된다. 그리고, 가을 의 해황 특성인 서로 다른 이질수괴의 경계역인 안상부 해황의 중심에 높은 생물량을 나타냈다. 3. 제주해협에서 patch의 형태로 생물량 분포가 높게 나타나는 해역의 외측에 좋은 갈치어장이 형성되었다.

• Environmental Engineering Research
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• 제19권1호
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• pp.91-99
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• 2014

Ordinary heterotrophic organism (OHO) active biomass plays key roles in biological wastewater treatment processes. However, due to the lack of measurement techniques, the OHO active biomass exists hypothetically within the design and simulation of biological wastewater treatment processes. This research was purposed to develop a quick and easy quantifying technique for the OHO active biomass applying a modified batch aerobic growth test. Two nitrification-denitrification activated sludge systems, with 10- and 20-day sludge ages, were operated to provide well-cultured mixed liquor to the batch tests. A steady state design model was firstly applied to quantify the "theoretical" OHO active biomass concentration of the two parent systems. The mixed liquor from the parent systems was then inoculated to a batch growth test and a batch digestion test to estimate the "measured" OHO active biomass concentration in the mixed liquor. The measured OHO active biomass concentrations with the batch growth test and the batch digestion test were compared to the theoretical concentrations of the parent system. The measured concentrations with the batch growth test were generally smaller than the theoretical concentrations. However, the measured concentrations with the batch aerobic digestion tests showed a good correlation to the theoretical concentrations. Thus, a different microbial growth condition (i.e., a higher food/biomass ratio) in the batch growth test, compared to the parent system or the batch digestion test, was found to cause underestimation of the OHO active biomass concentrations.

• Ocean and Polar Research
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• 제26권2호
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• pp.113-120
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• 2004

The abundance, biomass and distribution of phytoplankton, bacterioplankton and heterotrophic protists in the Bering Sea were investigated from July to August 1999. Chlorophyll a concentrations in the surface waters ranged from 0.16 to $3.79{\mu}g\;l^{-1}$ Nano-phytoplankton were found to constitute from 63 to 98% of the total phytoplankton biomass, and were clearly the dominant primary producers. The biomass of bacterioplankton in the surface layers varied from 1.46 to $20.2{\mu}g\;C\;l^{-1}$ and accounted for 30% of the total phytoplankton biomass. The biomass of bacterioplankton integrated over a depth of 0 to 100m averaged 65.4% of the total phytoplankton biomass. The surface biomass of heterotrophic protists ranged from 1.2 to $27.4{\mu}g\;C\;l^{-1}$, and was within the same order of magnitude as that of bacterioplankton. Of the total biomass of heterotrophic protists in the upper 100m of the water column, 65% was attributed to protists in the nano-size class. The results of this study suggest that bacteria and nano-protists are important components of the planktonic community in the Bering Sea during the summer season. The abundance of bacterioplankton and planktonic protists decreased from the western to northeastern and eastern regions of the Bering Sea. The abundance of these organisms also decreased with depth. The available evidence suggests that variation in the abundance and distribution of these organisms may be affected by water currents and vertical temperature variation in the Bering Sea.

• Journal of Ecology and Environment
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• 제33권4호
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• pp.351-361
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• 2010

The primary purposes for using fire are to enhance marsh vegetation to support waterfowl, and to manage invasive plant species. The study was conducted for two consecutive years in 2004 and 2005, investigating the effects of prescribed fire regimes on vegetation biomass in tidal brackish marsh areas of the Blackwater National Wildlife Refuge located on the eastern shore of Maryland, USA, that are under relatively similar environmental conditions. Four different burn regimes (i.e., annual burn, 3-5 year burn, 7-10 year burn, and no burn) were applied in the study. Above- and below-ground vegetation biomass samples as affected by the different burn regimes were harvested in each year for five plant species native to the marsh; Distichlis spicata, Spartina alterniflora, Schoenoplectus americanus, Spartina cynosuroides and Spartina patens. No significant difference was found either in total above-ground biomass or in above-ground biomass by species between burn regimes in 2004. However, more total above-ground biomass was produced in annual burn regime in 2005 than in the other burn regimes. There were no consistent effects of burning on vegetative biomass production by species, but it seemed D. spicata was somewhat benefited by prescribed burning for its biomass production. Moreover, the stem density for D. spicata under annual burn regime was significantly higher than that in the other burn regimes, showing some positive effects of burning on vegetation. The below-ground biomass was significantly greater in 2004 than in 2005, yet with no significant difference between burn regimes in either year. A longer-term monitoring is strongly recommended.