• Title/Summary/Keyword: 축적

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Uptake and Fate of Inorganic Mercury in the Eastern Oyster, Crassostrea virginica (이스턴 오이스터 Crassostrea virginica 에서 무기수은의 섭취와 축적)

  • Cho, Jung H.
    • Journal of Environmental Health Sciences
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    • v.9 no.1
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    • pp.63-76
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    • 1983
  • 중금속은 해수에서보다 해수중의 생물계에 그 농도가 더 높은 것으로 알려져 있으며 수은도 무기형으로 생물계에 존재하다가 생물활동으로 인해 알킬형으로 변한다. food chain이 미량금속 축적의 주통로로 알려져 있으나 그외 몇가지 방법이 제시되고 잇다. 특히 연체동물은 미량금속의 축적현상이 온도, 폭로시간, 시간, 생리적 활동에 다라 상당히 달라진다. 또한 유기알킬 수은이 무기수은보다 비교적 낮은 독성을 나타내지만 후자의 피해도 무시할 수는 없다. 굴(crassostrea virginica)은 염화수은농도가 비교적 낮은 상태에서도 상\ulcorner량의 축적현상을 보여주었다. 두개의 compartment system을 연계적인 상태에서 보면 첫 compartment에서의 초기축적은 가역적이었으나 둘째 Compartment에서 측정된 원실율로 보아 비가역적 축적이상을 확인해 주었다. 뿐만 아니라 미량금속이 아가미와 외부 근육에서 가장 높은 축적률을 보인것은 flow system의 regression moder과 매우 흡사함을 암시하며 농도가 낮은 상태에서의 축적이상에 중요한 의미를 부여하였다.

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THE ACCUMULATION OF FREE PROLINE AT LOW TEMPERA TURES AND WATER STRESS IN BARLEY AND WHEAT (대 . 소맥에 있어서 저온 및 수분부족에 의한 유리 Prolie의 축적)

  • Won-Yul Choi;Don Aspinall
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.24 no.1
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    • pp.57-65
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    • 1979
  • In order to find the physiology of responess In order to find the physiology of responses and mechanisms of the actumlation of free proline at low temperatures and water stress. the temperature range, the effect of prolonged exposure to low temperatures, the light-dependence of proline accumulation in barle was significantly lower than in wheat. Proline accumulation at 5\circ C without water stress was shown to be light-dependent. Proline accumulation by water stress was not light-dependent at 2$0^{\circ}C$ but at 5$^{\circ}C$.

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납에 오염된 토양에서 생장한 애기장대의 식물기관에 축적된 납 농도

  • Park, Jong-Beom
    • Proceedings of the Korean Environmental Sciences Society Conference
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    • 2008.11a
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    • pp.165-167
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    • 2008
  • 토양 속에 첨가된 납의 농도가 증가하면 애기장대 식물체 내에 축적된 납의 농도도 증가하였는데, 특히 오염물질 배출기준농도보다 50배 높은 납이 첨가된 토양에서 생장한 식물체내에 축적된 납 농도는 정상식물보다 약 2.6배 증가하였다. 이러한 결과는 토양 속에 오염된 납은 식물의 줄기나 일보다는 뿌리에 더 많이 축적되며, 줄기와 잎에 축적되는 납농도는 토양 속에 오염된 납 농도에 비례하여 증가하지 않으나 뿌리에서는 농도에 비례하여 매우 증가하였음을 나타내고 있다.

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거세돈의 제한 급여 효과

  • 조성백
    • The Korea Swine Journal
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    • v.23 no.9 s.265
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    • pp.123-126
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    • 2001
  • 돼지 성별 사료섭취량 및 체조성과 관련된 시험 결과를 보면 자유채식시 사료섭취량은 거세돈이 암퇘지와 비거세돈보다 많으며, 적육 축적률은 낮다. 체중 30$\~$60kg의 비육기에 자유채식과 제한급여구를 비교한 결과 증체율과 지방축적률은 자유채식에서 높았으며, 거세돈의 에너지 섭취 수준을 $8\%$ 제한시 암퇘지를 자유채식시킨 경우와 비슷한 성장률을 보였다. 또한 80$\~$140kg의 체중에서 최대 단백질 축적량은 수퇘지 42.5kg 암퇘지 40.0kg, 거세돈37.5kg이고, 1일 단백질 축적량은 수퇘지 180g, 암퇘지 160g, 거세돈 145g정도로 성별로 차이가 있다. 체지방축적은 에너지 수준과 거세실시 여부, 일당증체량은 에너지 수준에 큰 영향을 받는다.

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Influence of Competing Ions and Metabolic Inhibitors on Heavy Metal Accumulation in the Cell of Heavy Metal-Tolerant Microorganisms (중금속내성균의 중금속 축적에 미치는 경쟁이온 및 대사저해제의 영향)

  • Cho, Ju-Sik;Lee, Hong-Jae;Heo, Jong-Soo
    • Korean Journal of Environmental Agriculture
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    • v.16 no.2
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    • pp.142-148
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    • 1997
  • This study was performed to develop the biological treatment technology of wastewater polluted with heavy metals. Heavy metal-tolerant microorganisms, such as Pseudomonas putida, P. aeruginosa, P. chlororaphis and P. stutzeri possessing the ability to accumulate cadmium, lead, zinc and copper, respectively, were isolated from industrial wastewaters and mine wastewaters polluted with various heavy metals. The effect of competing ions and metabolic inhibitors on heavy metal accumulation in the cells was investigated. Heavy metal accumulation into cells was drastically decreased in the presence of competing cation, $Al^{3+}$, and also decreased, at a lesser extent, in the presence of competing anions, $CO_3\;^{2-}$ and $PO_4\;^{2-}$. But heavy metal accumulation was not influenced generally in the presence of the other rations and anions. The accumulation of Cd, Zn or Cu by Cd-, Zn- or Cu-tolerant microorganism was remarkably decreased in the presence of metabolic inhibitors, but the accumulation of Pb by Pb-tolerant microorganism was little affected in the presence of metabolic inhibitors. These results suggested that the accumulation of Cd, Zn or Cu by Cd-, Zn- or Cu-tolerant microorganism was concerned with the biological activity depending on energy, and the accumulation of Pb by Pb-tolerant microorganism depended on not the biological activity but the physical adsorption on the cell surface. Each heavy metal-tolerant microorganism also exhibited some ability to accumulate the other heavy metals in solution containing equal concentrations of cadmium, lead, zinc and copper, when measured at 48 hours after inoculation of the microorganisms, but the accumulation rates were somewhat low as compared to the accumulation rates of heavy metal fitting to each tolerance. These results suggested that the accumulation of each heavy metal by each heavy metal-tolerant microorganism was a selective accumulation process.

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Characterization and Condition of Silver Accumulation Bacteria in Groundwater (지하수에서 분리한 은(銀) 축적균주에 대한 축적조건 및 특성)

  • 배진희;민병례;한명수;최영길
    • Korean Journal of Microbiology
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    • v.37 no.4
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    • pp.273-276
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    • 2001
  • The strain which accumulate the silver in cell were isolated and characterized. And condition of accumulation of heavy metal was examined closely to investigate optimal condition of accumulation. Pseudomonas fluorescens and Bacillus cereus were Isolated from groundwater as the strain of silver accumulating bacteria. These strains did not grow in the medium at silver over the concentration 20 ppm. The largest accumulations of silver in the culture of Pseudomonas fluorescens and Bacillus cereus occurred within 24 hours. The amount of silver accumulation in Pseudomonas fluorescens and Bacillus cereus were 1.9 mg/g cell and 1.65 mg/g cell, repletively. In protein patterns of cell after the treatment of silver, three reducible proteins (126 KDa, 89 KDa, 25 KDa) in Bacillus cereus and one new protein (34 KDa) in Pseudomonas fluorescens were detected by SDS-PAGE.

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Production of Bioplastics from Activated Sludge in a Mixed Culture (혼합배양계에서 활성오니를 이용한 생분해성플라스틱 생산 연구)

  • Cho, Jae-Kyoung
    • Journal of the Korea Organic Resources Recycling Association
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    • v.9 no.3
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    • pp.119-126
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    • 2001
  • A process for the production of bioplastics from wastewater with an open microbial culture was developed and evaluated. The process consists of a selection reactor to select bacteria in feast/famine regime and an accumulation reactor to produce PHA using selected bacteria. Polyhydroxyalkanoate(PHAs) accumulating bacteria could be efficiently grown in a sequencing batch reactor(SBR) without any growth limitation. For the high production of PHA limitation such as oxygen and nutrients seemed to be needed. Accumulation experiments were performed to evaluate the level of accumulation of PHA. Limited aeration had no effect, but nutrients limitation showed high accumulation. Bacteria which were selected in the SBR could accumulate PHA till 60% of cellular dry weight in accumulation experiments under nitrogen limitation. PHA accumulation rate decreased with increasing PHA content in the cells. Clearly, PHA accumulation rate has a strong correlation with the PHA content of the cells.

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Analysis of Forest Fire Conditions on Forest Structure Changing Annually (우리나라 연도별 숲구조 변화에 따른 산불발생 상황 분석)

  • Han, Seung-Kil;Lee, Si-Young;Lee, Hae-Pyeong
    • Proceedings of the Korea Institute of Fire Science and Engineering Conference
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    • 2010.04a
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    • pp.438-442
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    • 2010
  • 우리나라의 산림면적은 연도가 경과함에 따라 감소한 반면, 임목축적은 지속적으로 증가하였으며, 임상별 면적과 축적은 침엽수의 비중이 가장 높고 혼효림, 활엽수 순으로 나타나고, 영급은 현재 III, IV영급이 많이 분포하는 영급구조로 변화되었다. 또한 임목축적별 건당 피해면적과 재적, 피해면적당 피해수량은 임목축적이 증가함에 따라 증가하는 경향이 있었다. 또한, 피해면적과 재적이 급격히 증가되는 임목축적 3억$m^3$구간은 95년 이후로 이 당시 임목영급은 II, III영급으로 과거보다 산림연료가 풍부해 지는 시기며, 숲가꾸기 단계상 간벌단계로 임목간 밀도가 심하고 고사지의 발생 등 사다리형 연료 발달이 쉬워 대형 산불이 자주 발생한 것으로 판단된다.

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A Post-Keynesian Analysis of the Effects of Government Financial Expenditure on Capital Accumulation (정부의 금융지출이 자본축적 경로에 미치는 효과: 포스트 케인지언 분석)

  • Ko, Min-Chang;Lee, Sangheon
    • 사회경제평론
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    • no.38
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    • pp.163-198
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    • 2012
  • This analysis suggests a post Keynesian macro-dynamic model that integrates a financial variable, firm's debt, into the post Keynesian model of growth and distribution. On the basis of it, this study analyzes the effects of government financial expenditure on capital accumulation empirically. It also studies empirically whether a regime shift has arisen since Asian financial crisis in 1997. This paper shows that government financial expenditure has exerted an positive effect on capital accumulation. This empirical result supports government intervention in financial market in recurrence of financial crises. This study also finds grounds for a change in accumulation regime since Asian financial crisis in 1997.

Effect of External Factors on Heavy Metal Accumulation in the Cell of Heavy Metal-Tolerant Microorganisms (중금속내성균의 중금속 축적에 미치는 외부요인의 영향)

  • Cho, Ju-Sik;Lee, Hong-Jae;Lee, Won-Kyu;Heo, Jong-Soo
    • Korean Journal of Environmental Agriculture
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    • v.16 no.2
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    • pp.124-129
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    • 1997
  • This study was performed to develop the biological treatment technology of wastewater polluted with heavy metals. Heavy metal-tolerant microorganisms, such as Pseudomonas putida, P. aeruginosa, P. chlororaphis and P. stutzeri possessing the ability to accumulate cadmium, lead, zinc and copper, respectively, were isolated from industrial wastewater and mine wastewater polluted with various heavy metals. The effect of several external factors, such as temperature, pH and heavy metal compounds on heavy metal accumulation in the cells was investigated. The amount of heavy metal accumulation into cells according to the kind of heavy metal compound was slightly increased in the case of the heavy metal compound with -nitrate group, but generally, there is little change according to the kind of compound in the amount of heavy metal accumulation. The amount of heavy metal accumulation according to the precultured time was increased in the case of the cell precultured for 24 hours, but generally the precultured time did not affect to the amount of heavy metal accumulation. Heavy metal accumulation into cells was affected by several external factors, such as temperature and pH. The optimum temperature and optimum pH of the accumulation of heavy metal into cells were $20{\sim}37^{\circ}C$ and pH $6{\sim}8$, respectively. By increasing the concentration of each heavy metal-tolerant microorganism in the solution, the total amount of heavy metal accumulated was increased, whereas the amount of heavy metal accumulated per cell(mg, heavy metal/g, dry cells) was decreased. These results indicated that the amount of heavy metal accumulated was not proportional to the concentration of microorganisms.

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