• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• 제4권2호
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• pp.111-116
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• 2000

Transboundary air pollution has recently become an area of increasing scientific interest and political concern as countries are receiving air pollutants from their neighbors. In order to gain a better understanding of the long-range transport processes of air pollutants and the source-receptor relationships among neighboring countries, an atmospheric transport model coupled with a RAMS(Regional Atmospheric Modeling System) model was applied to the East Asia region during the entire month of January 1993. The scalar transport option of the RAMS model was used to calculate special atmospheric constituents such as trace gases or aerosols. The sulfate production in clouds and rainwater and its removal processes by dry and wet deposition were considered. The sulfate budget from source regions to receptor regions was estimated by analysing the source-receptor relationships. When a specific receptor site revealed a sulfate value higher than the sulfate concentration based on its own source origin, this was taken to indicate long-range transport from another source region. The contribution ratio from various source region was calculated. The contribution ratio of dry and wet deposition was higher on the main continent of the East region. Furthermore, the high deposition amounts were identified on the west coast of Korea and the East China Sea.

• KSBB Journal
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• 제21권6호
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• pp.428-432
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• 2006

본 연구는 미생물이 오염물 분해를 위해 황산염이 필요한 동전기 생물학적복원에서 황산염원의 종류가 제거효율에 미치는 영향을 조사하였다. 대표오염물과 적용 미생물은 각각 phenanthrene과 Sphingomonas sp. 3Y였다. Magnesium sulfate를 이용했을 때 Mg이온은 음극에서 전기적으로 생성되는 수산화이온과 결합하여 전해질 pH를 크게 감소시키고 미생물활성을 저해하는 현상이 관찰되었다. 따라서 ammonium sulfate와 disodium sulfate를 이용했을 때 전해질 및 토양 pH가 중성영역으로 유지되었으며 미생물 활성도 높게 유지되었다. 하지만 전자의 경우 ammonium이 미생물의 오염물 분해를 지연시켜 제거효율이 오히려 magnesium sulfate의 21.8%보다 12.0%로 더 낮게 나타났으며, 반면 후자의 경우 27.2%로 제거효율이 증가된 것을 관찰할 수 있었다. 이와 같은 제거효율의 차이는 장기간의 처리에서는 더욱 두드러질 것으로 예상된다.

• 상하수도학회지
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• 제13권2호
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• pp.47-54
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• 1999

SRB(Sulfate Reducing Bacteria) converts sulfate into sulfide using an organic carbon source as the electron donor. The sulfide formed precipitates the various metals present in the AMD (Acid Mine Drainage). This study is the fundamental research on heavy metal removal from AMD using SRB. Two completely mixed anaerobic reactors were operated for cultivation of SRB at the temperature of $30^{\circ}C$ and anaerobic batch reactors were used to evaluate the effects of carbon source, COD/sulfate($SO_4^=$) ratio and alkalinity on sulfate reduction rate and heavy metal removal efficiency. AMD used in this study was characterized by low pH 3.0 and 1000mg/l of sulfate and dissolved high concentration of heavy metals such as iron, cadmium, copper, zinc and lead. It was found that glucose was an organic carbon source better than acetate as the electron donor of SRB for sulfate reduction in AMD. Amount of sulfate reduction maximized at the COD(glucose)/sulfate ratio of 0.5 in the influent and then removal efficiencies of heavy metals were 97.5% of Cu, 100% of Pb, 100% of Cr, 49% of Mn, 98% of Zn, 100% Cd and 92.4% of Fe. Although sulfate reduction results in an increase in the alkalinity of the reactor, alkalinity of 1000mg/1 (as $CaCo_3$) should be should be added continuously to the anaerobic reactor in order to remove heavy metals from AMD.

• 한국환경과학회:학술대회논문집
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• 한국환경과학회 2003년도 International Symposium on Clean Environment
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• pp.216-225
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• 2003

Fine particles with aerodynamic diameter less than 2.5 ${\mu}m$ (PM2.5) were collected from three sites in Beijing during April, August, and November 2000 and January 2001. After chemical components in samples are analyzed, a chemical mass balance (CMB) receptor model using PARs as tracers is applied to quantify the source contributions to PM2.5 in Beijing. The results show that the major sources are coal combustion, fugitive dust, vehicle exhaust, secondary sulfate and nitrate, and organic matter while biomass burning and construction dust contribute only a small fraction. In addition, source inventory in Beijing is used to determine the primary source contributions. The two methods result in comparable results. Source apportionment at three sampling sites presents similar contributions to PM2.5 although the sites are far away from each other. However, distinct seasonal pattern is presented for the source contributions from coal combustion, fugitive dust, biomass burning, secondary sulfate and nitrate.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2006년도 총회 및 춘계학술발표회
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• pp.209-212
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• 2006

Using sulfur sotope analysis of dissolved sulfate in surface water, we have investigated the source of sulfate in order to identify the abandoned metallic mines, which have the potential of heavy metal contamination within watershed. The range of the sulfur isotope values for dissolved sulfate in stream waters (DD-1 and 2) are similar to those of sulfides from the Dunjun mine, which suggests that oxidation of sulfides is the principal source of $SO_4^{2-}$ in these stream waters. Also, heavier sulfur isotopes in waters near Baekjun and Hamchang mines imply the possibility of contamination in waters by these metallic mines.

• Biotechnology and Bioprocess Engineering:BBE
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• 제1권1호
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• pp.41-45
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• 1996

Effects of yeast extract and ammonium sulfate were investigated on the production of L-or-nithine by an arginine auxotroph, Brevibacterium ketoglutamicum in flask and batch cultures. Yeast extract as an arginine source and ammonium sulfate as an inorganic nitrogen source had significant effects on L-ornithine production and cell growth. L-ornithine production was repressed by the excessive addition of arginine. Reversion of auxotrophic cells to the wild type was observed when the initial yeast extract concenfration was too low. There existed optimum concentrations of yeast extract and ammonium sulfate for L-or-nithine production. The effects of yeast extract and ammonium sulfate concentrations of the Leudeking-Piret model parameters were examined to analyze the relationship between cell growth and L-ornithine production.

• 한국환경과학회지
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• 제17권4호
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• pp.359-364
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• 2008

PM10 samples were collected from July 2007 to Oct. 2007 at Gwaebopdong(inland area) and Dongsamdong(coastal area), in Busan. This paper investigates the contribution of emission sources to PM10 mass in Busan. Source apportionment results derived from the chemical mass balance(CMB) method. A source profiles applied in this study is organized to minimize the collinearity among sources type via statistical method. Source profiles applied in this study utilized a measured value of fine particle directly sampled from metropolitan area such as Seoul and Incheon, After a CMB modeling, sulfate and nitrate related sources among those contributing to PM10 in Busan showed high contribution by 36.53% in Gwaebopdong and 42.02% in Dongsamdong.

• KSBB Journal
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• 제11권5호
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• pp.613-621
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• 1996

Wild-type 곰팡이인 Tolypoc/adium inflatum의 고정상배양을 통해 탄소원, 질소원, 아미노산 등이 peptide 항생제 계통 의 면역억제제인 cyclosporin A(CyA) 생합성에 미치는 영향을 조사하였다. 질소 원으로서 ammonium sulfate가 첨가된 경우에, f fructose 또는maltose 등을 탄소원으로 이용하는 배 지가 glucose가 첨가된 배지에 비해 월등히 높은 C CyA 생산성을 보였으나. ammonium sulfate의 부 재시에는 탄소원들의 종류에 관계없이 CyA 생산성 이 매우 낮게 나타났다. 질소원의 경우는 무기 질소 원인 ammonium sulfate가 CyA 생산에 가장 훌륭 한 성분으로 작용했으며, 그밖에 ammonium phos p phate, ammonium citrate 역시 CyA 생산을 어느 정도 증가시키는 효과를 보였다. 최척 ammonIum s sulfate의 농도는 109/L로 밝혀 졌으며 배양초기 에 a ammonium sulfate릎 첨가해 주는 경우가 배양중간 에 첨가하는 경우보다 CyA 생산에 더 효율적인 것 으로 나타났다. 아미노산의 경우 L-valine에 의한 C CyA 생합성 증진 효과가 가장 투렷하게 나타났다. 최적 L-valine 농도는 109/L이였으며 L-valine이 배양 초반부터 배지 중에 존재하는 것이 CyA 생합 성에 가장 유리한 것으로 나타났다.

• 한국미생물·생명공학회지
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• 제18권6호
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• pp.553-559
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• 1990

많은 관심이 집중되고 있는 환경오염의 대처방안의 일환으로, plastic 및 wrap 제조시 가소제로 가장 널리 사용되고 폐수 중에 대량 유출되어 인체에 유독한 난분해성 고분자 유기합성 물질로서 문제가 되고 있는 phthalate ester의 일종인 dibutyl phthalate(DBP)를 분해 자화할 수 있는 미생물을 분리하고자 했다. 저자들은 대구 근교의 토양 및 sludge에서 DBP 분해 관련 효소인 protocatechuate dioxygenase을 생성하는 새로운 균주를 분리하여 동정하였다.

• Asian-Australasian Journal of Animal Sciences
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• 제19권4호
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• pp.601-604
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• 2006

The objective of this study was to investigate technical methods for extraction of mucopolysachharide-protein containing chondroitin sulfate from keel cartilage of chickens. The chemical composition of chicken keel cartilage was determined. For the preparation of mucopolysaccharide-protein from lyophilized chicken keel cartilage, hot water extraction and alcalase hydrolysis methods were examined. Results showed that the optimum condition of hot water extraction was incubation for 120 min with a yield of 40.09% and chondroitin sulfate content of 28.46%. For alcalase hydrolysis, the most effective condition was 2% alcalase in 10 volumes of distilled water for 120 min. The yield of hydrolysate was 75.87%, and chondroitin sulfate content was 26.61%. For further separation of chondroitin sulfate from the alcalase hydrolysate, which has a higher yield than that of hot water, 60% ethanol precipitation was performed. The yield of the ethanol precipitate was 21.41% and its chondroitin sulfate content was 46.31%. The hot water extract, alcalase hydrolysate and ethanol precipitate showed similar electrophoretic migration with standard chondroitin sulfate (chondroitin sulfate A), using cellulose acetate membrane electrophoresis. These results indicated that a significant amount of mucopolysaccharide-protein containing chondroitin sulfate could be acquired form chicken keel cartilage. Therefore, keel cartilage in chicken may provide an inexpensive source of chondroitin sulfate for commercial purposes.