• 제목/요약/키워드: atmospheric $CO_2$ concentration

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도시 대기중 중금속에 관한 연구 -서울시 신촌지역을 중심으로- (Heavy Metals in Ambient Air at Shinchon Area in Seoul)

  • 정용;장재연;주의조
    • 한국대기환경학회지
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    • 제3권2호
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    • pp.18-26
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    • 1987
  • In order to investigate the character of air pollution by heavy metals and to elucidate the possible sources in Seoul city, this study was performed to measure the concentrations of heavy metals of total suspended particulate and air pollutants such as $SO_2, NO_2, CO, CH_4$, Non-methane hydrocarbon, ozone at the residential-traffic area (shinchon dong) in January and February, 1986. The results are as follows: 1. $SO_2$ and TSP concentration were 135ppb and 167 $\mug/m^3$ in average, respectively. 2. While concentrations of heavy metals such as Fe, Cu, Pb in the ambient air seems gradually decreasing annually, Ni compound has been shown the tendency of increasing. 3. Among heavy metals in TSP analysed, the iron was detected at the highest level, 0.905% and the cadimium was the lowest 0.004% in average, respectively. 4. V, Fe and Zn compounds in air were observed to be highly correlated with their correlation coefficients(r) higher than 0.7. Pb compound was highly correlated to the levels of Zn and Fe, however relatively less correlated to V compound. 5. Among concentrations of heavy metals in the particulates, V and Ni compounds were highly correlated with coefficient(r) of 0.8587; the cause might be imagined by the fact of releasing from combustion of fuel oil. Fe, Pb and Zn compounds were highly correlated $SO_2$ concentration. It might be explained that they were released by combustion of coal. 6. The level of $SO_2$ was highly correlated to most of heavy metals: especially correlation coefficient(r) to Pb compound was 0.9081. Pb compound was also highly correlated to NO, CO and TSP. TSP showed higher correlation to Pb and Cd compounds than to V and Ni compounds. It might be assumed that particulate was mainly produced by combusting coal from space heating and by exhausting gasoline and diesel oil from transportation rather than by burning fuel oil.

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온도 및 CO2 상승이 고추의 생육 및 과실품질에 미치는 영향 (Impact of Elevated Temperature and CO2 on Growth and Fruit Quality of Pepper (Capsicum annuum L.))

  • 송은영;문경환;손인창;위승환;김천환;임찬규;오순자
    • 한국농림기상학회지
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    • 제18권4호
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    • pp.179-187
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    • 2016
  • 본 연구는 미래 기후변화 시나리오에 근거하여 예측되는 온도 및 이산화탄소 농도 상승조건에서 노지채소인 '무한질주' 고추의 생육 및 과실품질에 미치는 영향을 구명하기 위해 SPAR (Soil Plant Atmosphere Research) 챔버에서 수행하였다. 대조구인 대기온도는 노지고추 주산지인 안동지역의 평년(1971~2000; 30년) 5~10월의 생육기 평균기온($20.8^{\circ}C$)을 기준으로 설정하였다. 처리구는 대조구(대기온도, 400ppm $CO_2$), 이산화탄소 상승구(대기온도, 800ppm $CO_2$), 온도 상승구(대기온도+$6^{\circ}C$, 400ppm $CO_2$), 이산화탄소+온도 상승구(대기온도+$6^{\circ}C$, 800ppm $CO_2$) 등 4수준으로 설정하였다. 대조구보다 고온 및 상승 이산화탄소 농도 조건에서 재배하였을 때 초장, 분지수, 엽수 등이 증가하였으나, 엽면적과 SPAD값은 급격히 감소하였다. 개화 및 꽃봉오리수도 온도 및 이산화탄소 농도가 증가할수록 급격히 감소되었다. 또한, 개체당 총 착과수와 총 착과중도 대조구에 비해 감소하였는데 과실무게도 약간 적었고 과실 길이와 과실 두께도 약간 줄었다. 이상의 결과로 보아 기후변화시나리오에 근거로 대기 중 $CO_2$ 농도는 2배, 기온은 $6^{\circ}C$ 높은 환경 조건에서는 고추의 착과가 저해되고 과실 수량도 크게 감소하였으나, 완숙 과실의 비율은 증가하여 수확시기가 다소 앞당겨질 것으로 보인다.

초미세먼지 주의보 시 지식산업센터 사무실의 실내 초미세먼지 농도 특성과 공기청정기와 환기장치의 영향 (Characteristics of Indoor PM2.5 and the effect of air purifier and ventilation system on Indoor PM2.5 in the Knowledge Industrial Center office during the atmospheric PM2.5 warning)

  • 지준호;주상우
    • 한국입자에어로졸학회지
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    • 제16권3호
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    • pp.65-72
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    • 2020
  • 본 연구에서는 초미세먼지 주의보가 발효된 2019년 3월 4일~7일까지 약 80시간 동안 국내 지식산업센터 사무실 내 실내 미세먼지와 초미세먼지 농도를 측정하였다. 측정이 이루어지는 동안 공기청정기와 환기장치의 구동에 의한 영향을 확인하였고, 초미세먼지 주의보 날의 실내와 실외의 입자 크기분포를 분석하였다. 사무실의 테라스 쪽 이중 창문과 복도쪽 입구 출입문을 모두 닫은 밀폐 조건에서 실외 대비 실내의 초미세먼지 농도비는 약 40% 정도를 유지했다. 초미세먼지 주의보의 시기에 중성능급 필터가 장착된 환기장치의 풍량을 1단이나 2단으로 운전한 경우에도 외기 대비 실내 초미세먼지 농도는 환기하지 않고 밀폐만 했을 때의 조건과 비슷했다. 환기장치를 구동하지 않고, 문을 닫아둔 조건에서 공기청정기를 가동하면 실내 초미세먼지 농도를 초미세먼지 주의보 시에도 대기 초미세먼지 농도대비 약 20% 수준으로 감소시킬 수 있었지만, 환기장치의 풍량을 증가시켜 가동하면, 상대적으로 환기를 통해 미세먼지를 공급하는 공기량이 증가하여, 공기청정기의 효과가 감소하였고, 실내외 농도비를 약 36%로 유지하는 것을 확인하였다. 사무실 내 실내 부유 먼지의 크기분포의 분석 결과 1 ㎛ 보다 큰 입자의 농도는 매우 낮았다. 대기의 입자 크기분포는 1 ㎛ 이하의 입자의 봉우리와 1~10 ㎛ 입자의 봉우리의 두 부분으로 나타나는데 비해, 실내 입자의 크기분포에서는 1~10 ㎛ 입자의 봉우리가 사라지고 1 ㎛ 이하의 입자의 봉우리만 남는 형태로 상대적으로 큰 입자의 농도가 미미했다. 사무실의 밀폐가 초미세먼지 농도의 감소에 효과가 있었지만, 대부분은 1 ㎛ 보다 큰 입자가 제거되었고, 인체에 더 영향을 미치는 1 ㎛ 이하의 입자는 실내로 쉽게 침투하였다. 결국 밀폐된 사무실 실내에서 공기청정기의 사용은 1 ㎛ 이하의 인체에 더 해로운 크기의 입자를 제거하는데 큰 효과를 얻을 수 있음을 확인하였다. 본 연구는 단지 80시간의 짧은 시간의 실증 데이터를 분석한 결과이지만, 초미세먼지 주의보가 1년 중 1주일 이내로 발생하는 한정된 기간에 발생한다는 점에서 측정 및 분석 데이터가 중요한 의미를 갖는다고 생각된다. 또한 실내 초미세먼지 농도에 영향을 미치는 다양한 변수들을 고려하여 측정 계획을 작성하여 실증 측정이 이루어졌기 때문에 비교적 신뢰성 있는 분석데이터를 제시할 수 있었다.

Methyl yellow와 Methyl orange 지시약을 이용한 실내공기중의 포름알데히드 간이측정기에 대한 연구 (A Study on a Passive Sampler for Indoor Formaldehyde Using Methyl Yellow and Methyl Orange Indicator)

  • 정상진;장재철
    • 한국대기환경학회지
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    • 제20권6호
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    • pp.793-801
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    • 2004
  • A passive sampler has been developed for measuring formaldehyde in air using methyl yellow and methyl orange indicator. It is based on the color change of the TLC plate on reaction with formaldehyde. TLC plates impregnated with three kinds of solutions containing methyl orange, methyl yellow, mixing of methyl yellow and methyl orange were shown rectilinear response to formaldehyde concentration at constant exposure time. The color change of impregnated TLC plate with criteria air pollution, such as NO$_2$, SO$_2$, CO, $O_3$ was investigated. The color change of TLC plate with $O_3$ is larger than other gases.

이동 측정방법을 사용한 부산지역 주요 도로의 대기오염도 조사 (An Investigation into Air Quality of Main Roads in Busan using Mobile Platform Measurement)

  • 도우곤;정우식;유은철;곽진
    • 한국환경과학회지
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    • 제22권9호
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    • pp.1199-1211
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    • 2013
  • Mobile sources produce a significant fraction of total anthropogenic emissions in Korea and have harmful effects on air quality. Mobile emissions are intrinsically difficult to estimate due to complicated road networks and variations of traffic volume with location and time. To measure traffic pollutants with high temporal and spatial resolution under real conditions a mobile laboratory was designed. The mobile laboratory provide concentrations of $SO_2$, CO, NO, $NO_2$ and location coordinate value. This approach allowed for pollutant level measurements on many roads within short periods of time. In this study, on-road concentrations of $SO_2$, CO, NO and $NO_2$ were measured using mobile platform measurement along the 25 main roads in Busan to estimate the average air pollution level in short time difference. The measurements were conducted on favorable meteorological days from 2010 to 2012 and the overall concentrations of $SO_2$, CO, NO and $NO_2$ were 0.006, 0.8, 0.182 and 0.055 ppm respectively. The result showed that the concentration of CO, NO and $NO_2$ on road were twice, 18 times and 2.5 times higher than regional air quality monitoring sites mean in same period.

Air Pollution Trends in Japan between 1970 and 2012 and Impact of Urban Air Pollution Countermeasures

  • Wakamatsu, Shinji;Morikawa, Tazuko;Ito, Akiyoshi
    • Asian Journal of Atmospheric Environment
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    • 제7권4호
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    • pp.177-190
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    • 2013
  • Air pollution trends in Japan between 1970 and 2012 were analyzed, and the impact of air pollution countermeasures was evaluated. Concentrations of CO decreased from 1970 to 2012, and in 2012, the Japanese environmental quality standard (EQS) for CO was satisfied. Concentrations of $SO_2$ dropped markedly in the 1970s, owing to use of desulfurization technologies and low-sulfur heavy oil. Major reductions in the sulfur content of diesel fuel in the 1990s resulted in further decreases of $SO_2$ levels. In 2012, the EQS for $SO_2$ was satisfied at most air quality monitoring stations. Concentrations of $NO_2$ decreased from 1970 to 1985, but increased from 1985 to 1995. After 1995, $NO_2$ concentrations decreased, especially after 2006. In 2012, the EQS for $NO_2$ was satisfied at most air quality monitoring stations, except those alongside roads. The annual mean for the daily maximum concentrations of photochemical oxidants (OX) increased from 1980 to 2010, but after 2006, the $98^{th}$ percentile values of the OX concentrations decreased. In 2012, the EQS for OX was not satisfied at most air quality monitoring stations. Non-methane hydrocarbon (NMHC) concentrations generally decreased from 1976 to 2012. In 2011, NMHC concentrations near roads and in the general environment were nearly the same. The concentration of suspended particulate matter (SPM) generally decreased. In 2011, the EQS for SPM was satisfied at 69.2% of ambient air monitoring stations, and 72.9% of roadside air-monitoring stations. Impacts from mineral dust from continental Asia were especially pronounced in the western part of Japan in spring, and year-round variation was large. The concentration of $PM_{2.5}$ generally decreased, but the EQS for $PM_{2.5}$ is still not satisfied. The air pollution trends were closely synchronized with promulgation of regulations designed to limit pollutant emissions. Trans-boundary OX and $PM_{2.5}$ has become a big issue which contains global warming chemical species such as ozone and black carbon (so called SLCP: Short Lived Climate Pollutants). Cobeneficial reduction approach for these pollutants will be important to improve both in regional and global atmospheric environmental conditions.

수도권지역에서 수치 토지피복지도 작성을 통한 대기환경부문 활용사례 연구 - MM5내 기온 및 바람장의 민감도 분석과 식생분포에 기인한 VOC 배출량 및 CO2 플럭스의 실시간 산정을 중심으로 - (A Study on Examples Applicable to Numerical Land Cover Map Data for Atmospheric Environment Fields in the Metropolitan Area of Seoul - Real Time Calculation of Biogenic CO2 Flux and VOC Emission Due to a Geographical Distribution of Vegetable and Analysis on Sensitivity of Air Temperature and Wind Field within MM5 -)

  • 문윤섭;구윤서
    • 한국대기환경학회지
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    • 제22권5호
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    • pp.661-678
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    • 2006
  • Products developed in this research is a software which can transfer the type of shape(.shp) into the type of ascii using the land cover data and the topography data in the metropolitan area of Seoul. In addition, it can calculate the $CO_2$ flux according to distribution of plants within the land cover data. The $CO_2$ flux is calculated by the experimental equation which is compose of the meteorological parameters such as the solar radiation and the air temperature. The net flux was shown in about $-19ton/km^2$ by removing $CO_2$ through the photosynthesis during daytime, and in 2 ton/km2 by producing it through the respiration during nighttime on 10 August 2004, the maximum day of air temperature during the period of 3yr(2001 to 2004), in the metropolitan area of Seoul. Spatial distribution of the air temperature and the wind field is simulated by substituting the middle classification of the land cover map data, upgraded by the Korean Ministry of Environment(KME), for the land-use data of the United States Geological Survey(USGS) within the Meteorological Mesoscale Model Version 5(MM5) on 10 August 2006 in the metropolitan area of Seoul. Difference of the air temperature between both data was shown in the maximum range of $-2^{\circ}C\;to\;2.9^{\circ}C$, and the air temperature due to the land use data of KME was higher than that of USGS in average $0.4^{\circ}C$. Also, those of wind vectors were meanly lower than that of USGS in daytime and nighttime. Furthermore, the hourly time series of Volatile Organic Components(VOCs) is calculated by using the Biosphere Emission and Interaction System Version 2(BEIS2) including the new land cover data and the meteorological parameters such as the air temperature and so]ar insolation. It is possible to calculate the concentration of ozone due to the biogenic emission of VOCs.

Photoelectrochemical Water Oxidation and $CO_2$ Conversion for Artificial Photosynthesis

  • Park, Hyunwoong
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2013년도 제45회 하계 정기학술대회 초록집
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    • pp.70-70
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    • 2013
  • As the costs of carbon-footprinetd fuels grow continuously and simultaneously atmospheric carbon dioxide concentration increases, solar fuels are receiving growing attention as alternative clean energy carriers. These fuels include molecular hydrogen and hydrogen peroxide produced from water, and hydrocarbons converted from carbon dioxide. For high efficiency solar fuel production, not only light absorbers (oxide semiconductors, Si, inorganic complexes, etc) should absorb most sunlight, but also charge separation and interfacial charge transfers need to occur efficiently. With this in mind, this talk will introduce the fundamentals of solar fuel production and artificial photosynthesis, and then discuss in detail on photoelectrochemical (PEC) water splitting and CO2 conversion. This talk largely divides into two section: PEC water oxidation and PEC CO2 reduction. The former is very important for proton-coupled electron transfer to CO2. For this oxidation, a variety of oxide semiconductors have been tested including TiO2, ZnO, WO3, BiVO4, and Fe2O3. Although they are essentially capable of oxidizing water into molecular oxygen, the efficiency is very low primarily because of high overpotentials and slow kinetics. This challenge has been overcome by coupling with oxygen evolving catalysts (OECs) and/or doping donor elements. In the latter, surface-modified p-Si electrodes are fabricated to absorb visible light and catalyze the CO2 reduction. For modification, metal nanoparticles are electrodeposited on the p-Si and their PEC performance is compared.

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서울지역의 PM10 중 미량원소의 특성 평가 (Trace Elements Characterization of PM10 in Seoul Area)

  • 신은상;최민규;영선우;정용삼
    • 한국대기환경학회지
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    • 제18권5호
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    • pp.363-372
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    • 2002
  • PM$_{10}$ aerosols were collected using low volume air sampler every month intervals from September 1992 to August 1991 in Seoul. These samples were analyzed for 20 trace elements (Al, As, Ba, Br, Ca, Cl, Co, Cr, Fe, K, Mn, Na, Ni, Pb, Sc, Se, Si, Ti, V and Zn) by INAA (instrumental neutron activation analysis), XRF (x-ray fuorescence spectrometer), and ICP (inductively coupled plasma). PM$_{10}$ mass concentrations higher than 70 $\mu$g/m$^3$ were 32% of 60 samples and had significantly higher concentrations in spring and winter than in summer and fall (p-value<0.001). The elements of As, Br, Cl, Ni, Pb, Se, V, and Zn are enriched by factors of 20 to 2,000 relative to their natural abundance in crustal soil. To further identify common sources of pollution-related trace elements, factor analysis was applied to the trace elements concentration data. Major sources that contribute to the atmospheric loading of these elements were found to include fossil fuel combustion, automobile and waste incineration (33.2%), metal processing industry (18.2%), and soil(29.8%).8%).