• Title/Summary/Keyword: 배경농도

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Preliminary Survey for the Design of the Air Pollution Monitoring System in Antarctic Area (남극지역의 대기오염 측정체계 구축을 위한 기초조사)

  • 김선태;홍성민;정의석;김성근
    • Proceedings of the Korea Air Pollution Research Association Conference
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    • 2000.11a
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    • pp.65-66
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    • 2000
  • 남극은 지리적인 원거리성과 혹독한 자연환경 등으로 문명에 의한 오염이 지구상에서 가장 적은 곳이며, 현재 우리가 거주하고 있는 각 대륙을 이해하는데 많은 기여를 하고 있다고 할 수 있다. 특히, 남극대륙을 대상으로 기상 및 기후학적인 관점에서 많은 연구가 수행되어 지고 있으며, 최근에는 지구온난화와 문제와 관련하여 남극대륙의 배경농도 측정 및 monitoring에 관심이 집중되고 있다. (중략)

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Diffused Aeration System(DAS)을 이용한 지하수내 TCE 제거 효율 평가: 주입 공기량에 따른 제거효율 비교

  • Kim Jin-Hun;Park Seong-Min;Seok Hui-Jun;Kim Hyeong-Su
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2006.04a
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    • pp.338-341
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    • 2006
  • 본 연구에서는 지하수내 TCE 농도가 높은 2개 지역을 선정하여 3회에 걸쳐 공기탈기법 시험을 실시하였다. 2개 지역의 지하수내 TCE 배경 농도는 각각 0.360, 0.317 mg/L이며 반응조에 주입된 공기는 각각 17.14, 44.78, 76.51 L/min의 비율로 주입하였다. 또한 반응조에서 배출되는 기체내의 TCE의 농도를 측정하기위해 PID(photo-ionization detector)를 장착하여 측정하였다. PID를 이용하여 배출되는 기체를 측정한 결과, TCE 농도는 $6{\sim}8$분만에 최고 농도로 배출되었고 시간이 지날수록 천천히 감소하는 형태를 나타내었다. 반응조내의 TCE 농도 변화는 공기 유입 속도에 따라 매우 큰 변화를 나타내었다. TCE가 17.14 L/min의 공기유입속도에서 160분 동안 64%, 44.78 L/min에서 135분 동안 93%, 76.51 L/min에서 120분 동안 95.3%가 제거되었다. 따라서 TCE를 제거하기 위한 DAS 기법은 공기의 주입비율에 따라 제거 속도의 큰 변화를 보였다.

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Effect of Human Follicular Fluid and Bovine Oviductal Tissue Extract on the Mouse Oocyte-Cumulus Complex (사람 난포액과 소의 수란관 조직추출액이 생쥐 난구세포에 미치는 영향)

  • 홍민정;김지수;심명선;김해권
    • Development and Reproduction
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    • v.6 no.2
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    • pp.97-104
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    • 2002
  • In most mammals, mature oocyte-cumulus complexer(OCCs) ovulate into the oviduct where fertilization by sperm takes place. However, the complex that fail to fertilize eventually undergoes degeneration while they reside in the oviduct. Yet there is no blown mechanism how both oocyte and cumulus cells degenerate. Using human follicular fluid (hFF), bovine oviductal tissue extract (BOX) and mouse OCC, the present study aimed to find how the oviduct influence the viability of the oocyte and cumulus cells in vitro. There was no difference of oocyte maturation rate between the control and BOX-treated groups. However, there was a significant difference in the survival of cumulus cells between two groups. Cumulus cells cultured in the presence of hFF alone underwent initially expansion and then they formed monolayer in the culture dish. Even after 72 hr, they proliferated well and showed fibroblast-like morphology. Cumulus cells cultured in the presence of both hFF and BOX also expanded after 24 hr, however, after 72 hr culture, they eventually detached and degenerated. Cumulus cells cultured in the BOX alone gave a similar drastic result. When the cumulus cells cultured in the presence of BOX were stained with DAPI, their nuclei showed partial condensation and fragmentation. After detailed analysis of these cells by TUNEL assay, many nuclei of them exhibited well stained spots indicating the signs of apoptosis. Based upon these observations, it is suggested that BOX might possess a factor that leads mouse cumulus cells to undergo apoptosis in vitro.

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Short-term Variability of Carbon Dioxide within and across the Korean Peninsula: Case Study during 1995-1997 (이산화탄소의 단주기적 농도변화 특성)

  • Song, Ki-Bum;Youn, Yong-Hoon;Kim, Ki-Hyun
    • Journal of the Korean earth science society
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    • v.21 no.5
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    • pp.623-634
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    • 2000
  • This study was conducted to analyze the patterns associated with the short-term variability of CO$_2$ concentrations over 24-h scale within and across the Korean Peninsula. In the course of our study, we compared the data sets obtained from Moo-Ahn (MAN) station located in the far western coastal area of Korea with those determined from major background observatory stations around the world from the periods of Aug. 1995 to Dec. 1997. The mean CO$_2$ concentration of the MAN area for the whole study periods, when computed using the daily mean values, was found out to be 374.5${\pm}$6.6 ppm (N=884); seasonal mean values were found out to be 378${\pm}$5.2 (spring: N=181), 372${\pm}$10.2 (summer: N =210), 372${\pm}$7.2 (fall: N=243), and 376${\pm}$5.4 ppm (winter: N=206). When the data from MAN was compared with those of major background stations, the effects of both daily and seasonal components appear to vary distinctively across different stations. Those effects are expected to reflect the mixed effects of various factors which include: seasonal pollution patterns, weather conditions, vegetation, and so forth. Based upon this comparative analysis, we suspect that the MAN area is under the strong influence of anthropogenic source processes relative to all the other stations under consideration. If that is not the case, the existence of enhanced CO$_2$ level may be rather ubiquitous phenomena in Korea. More detailed inspection of CO$_2$ behavior from various respects is strongly desired in the future.

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A Numerical Study on the Effects of Buildings and Topography on the Spatial Distributions of Air Pollutants in a Building-Congested District (건물 밀집 지역에서 대기오염물질 분포에 미치는 건물과 지형의 영향에 관한 수치 연구)

  • Kang, Geon;Kim, Jae-Jin;Lee, Jae-Bum
    • Korean Journal of Remote Sensing
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    • v.36 no.2_1
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    • pp.139-153
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    • 2020
  • Using a computationalfluid dynamics(CFD) model, thisstudy evaluated the representativeness of an air quality monitoring system (AQMS) in an urban area and presented a methodology to determine the suitable AQMS locations for specific purposes. For this, we selected a 1.6 km × 1.6 km area around the Eunpyeong-gu AQMS (AQMS 111181) as a target area. We conducted simulationsfor two emission scenarios (scenario one: air pollutants transported from inflow boundaries, scenario two: air pollutants emitted from roads). Urban airflows were markedly influenced by mountainous terrain located in the northeast and southeast of the target area, and complicated airflow patterns occurred around the buildings. The distributions of air pollutants were dependent on the terrain (mountain) in scenario one, but the road location and building height in scenario 2. We evaluated whether the AQMS could represent the air quality in the target area based on the simulations for two scenarios. The concentrations simulated at the AQMS were similar in magnitude to the layer mean concentrations, which indicated good representativeness for the air quality in the target area. We also suggested which locations were suitable for different measurement purposes (hot spots, clean zones, average zones, shelter zones, equi-background zones).

Evaluation on Natural Background of the Soil Heavy Metals in Korea (우리나라 토양의 중금속 자연배경농도 평가)

  • Yoon, Jeong-Ki;Kim, Dong-Ho;Kim, Tae-Seung;Park, Jong-Gyum;Chung, Il-Rok;Kim, Jong-Ha;Kim, Hyuk
    • Journal of Soil and Groundwater Environment
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    • v.14 no.3
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    • pp.32-39
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    • 2009
  • This study was conducted in order to get the scientific background for soil pollution criteria. The 92 soil samples derived from various geological units were taken and analyzed to survey natural heavy metal background levels using aqua regia digestion method and 0.1N HCl extraction method. From these results, the average natural contents of metals were 0.287 mg/kg for Cd, 15.26 mg/kg for Cu, 18.43 mg/kg for Pb, 25.36 mg/kg for Cr, 54.27 mg/kg for Zn, 17.68 mg/kg for Ni, 6.83 mg/kg for As by the aqua regia method, and 0.040 mg/kg for Cd, 0.48 mg/kg for Cu, 3.06 mg/kg for Pb, 0.09 mg/kg for Cr, 1.54 mg/kg for Zn, 0.27 mg/kg for Ni, 0.089 mg/kg for As by the 0.1N HCl extraction method. Ratios of soluble contents and total contents were Cd 0.14, Cu 0.03, Pb 0.17, Cr 0.004, Zn 0.03, Ni 0.02, As 0.013 and the correlation coefficients of soluble contents and total contents were 0.24(As), 0.88(Cd), 0.43(Cr), 0.65(Cu), 0.70(Pb), 0.61(Ni), 0.24(Zn). The correlation factor decreased in the order of Cd > Pb > Cu > Ni > Cr > Zn $\approx$ As.