2011-2015년 동안 한국 중부 태안과 청주 강내의 배경 관측지점에서 측정한 PM10, PM2.5 질량 농도를 분석하 였다. 황사 사례를 제외한 PM10 질량 농도의 계절변동에서 겨울-봄 동안 높은 농도는 서풍 기류에 의한 영향이 반영 되고 있으며, 여름에는 북태평양 기단과 잦은 강수로 낮은 수준을 보이고 있었다. 따라서, 일평균 PM10 질량 농도 81μg m-3 (미세먼지 예보 ‘약간 나쁨’ 이상) 이상의 사례도 겨울-봄 동안에 발생이 많으며, 특히 중국 동부 배출원에 가까 운 태안에서 더 많은 사례가 발생하고 있었다. 인위적으로 발생한 연무는 입경 2.5 μm 미만 입자의 구성 비율이 높다. 천리안 위성의 밝기온도차 분석에서 대기와 입자가 작은 연무는 −0.5 o K 이상에서 관측된다. 2011-2015년 동안 태안과 청주 강내에서 관측한 연무 사례일의 PM10 질량 농도와 NOAA 19 위성 밝기온도차를 분석하였다. PM10 질량 농도 는 200 μg m−3 보다 낮지만, PM2.5/PM10 질량 농도비는 0.4보다 높고 밝기온도차는 −0.3-0.5 o K 범위에 분포하고 있었 다. 그러나, PM10 질량 농도 190 μg m−3 이상인 황사 사례의 밝기온도차는 PM2.5/PM10 질량 농도비가 0.4보다 낮고, 밝기온도차는 −0.7 o K 이하의 범위에 분포하고 있었다. 이러한 연무의 밝기온도차 경계값 범위를 적용한 결과는 MODIS AOD, OMI AI의 에어로졸 분포 범위와 일치하였다.
동아시아에서 대기 에어로졸의 광역적 분포를 분석하기 위해 MODIS (Moderate Resolution Imaging Spectrometer) 센서에서 산출된 AOD (Aerosol Optical Depth)와 AE (Angstroom Exponent)를 이용하였다. 2009년 동아시아 지역에서 AOD는 3월(0.44±0.25)에 높았고, 9월(0.24±0.21)에 낮았다. 봄에는 중국 북부와 몽골의 사막, 건조지역에서 발생한 모래폭풍이 광역적으로 이동하여 동아시아의 AOD에 기여하고 있다. 그러나 동아시아의 풍하측에 위치한 한반도 중부의 안면도, 청원, 울릉도에서 PM10 (d≤10μm) 질량 농도는 2월에 최고를 보인 반면, AOD는 5월에 가장 높았다. 장마 전 상대습도의 증가에 따른 흡습성 에어로졸의 성장이 5월의 높은 AOD에 기여하고 있다. 여름(8월)에는 북태평양으로부터 해양성 기류와 잦은 강수에 의한 습윤 침전으로 AOD는 낮지만 중국 동부의 산업지역에서 광역적으로 발생한 미세 에어로졸로 인해 AE (1.30±0.37)가 가장 높은 값을 보였다. 안면도, 청원, 울릉도에서 MODIS AOD와 지상 PM10 질량 농도의 상관계수는 0.4-0.6이었다. 2009년 한반도 중부에서 관측한 황사 사례는 4회(6일)였고, 인위적 대기오염 이동 사례는 6회(12일)였다. 황사 사례와 인위적 대기오염의 이동 사례에서 안면도와 청원의 PM10 농도가 모두 증가하였다. 황사와 인위적 대기오염 이동으로 PM10이 증가하는 영역에서 AOD가 높게 나타나고 있다.
본 연구에서는 2006년부터 2008년까지 3년간 봄철에 PM10과 PM2.5를 채취하여 질량농도와 금속원소의 화학적 특성, 기상인자와의 관계 분석, 황사 및 비황사시의 미세먼지 특성 그리고 이동경로에 따른 농도의 특성을 고찰하였다. 연구기간동안의 PM10, PM2.5, PM10-2.5평균농도는 각각 126.2±89.8, 85.5±41.6, 40.7±54.9μg/m3이었으며 PM2.5/PM10 및 PM10-2.5/PM2.5 비는 각각 0.70, 0.48이었다. 우리나라의 북서쪽인 북경을 포함한 지역과 서쪽인 상해를 포함한 지역에서 공기덩어리가 이류 할 때 가장 높은 미세먼지농도를 나타내었다.
Aerosol mass size distributions were investigated at 865 m high the of Jirisan national park. A nanosampler cascade impactor was used to collect aerosols. The atmospheric aerosol particles had a unimodal mass size distribution, which peaked at 0.5–1.0 μm, and a mass aerodynamic diameter of 1.13 μm. The annual average concentrations of TSP, PM10, PM2.5, PM1, PM0.5 and PM0.1 were 20.9 μg/m3, 19.3 μg/m3, 14.9 μg/m3, 10.7 μg/m3, 5.3 μg/m3, 1.2 μg/m3, respectively. TSP concentrations were below 30 μg/m3 during the sampling period. On average PM10, PM2.5, PM1, PM0.5 and PM0.1 made up 0.91, 0.70, 0.41, 0.19 and 0.07 of TSP, respectively. The annual average of PM2.5/PM10 ratio was 0.77.
This study investigates weekday/weekend characteristics of PM10 and PM2.5 concentration and metallic elements in Busan in the springtime of 2013. PM10 concentration on weekday/weekend were 77.54 and 67.28 ㎍/㎥, respectively. And PM2.5 concentration on weekday/weekend were 57.81 and 43.83 ㎍/㎥, respectively. Also, PM2.5/PM10 concentration ratio on weekdays/weekend was 0.75 and 0.65, respectively. The contribution rates of Na to total metallic elements in PM10 on weekday/weekend were 38.3% and 38.9%, respectively. It would be useful in control effectively with management of urban fine particle to understand characteristics of fine particle concentration on weekday/weekend.
Atmospheric aerosol particles were investigated at GNTECH university in Jinju city. Samples were collected using the Nanosampler period from January to December 2014. The Nanosampler is a 6 stage cascade impactor(1 stage : > 10 μm, 2 stage : 2.5~10 μm, 3 stage : 1.0~2.5 μm, 4 stage : 0.5~1.0 μm, 5 stage : 0.1~0.5 μm, back-up : < 0.1 μm) with the stages having 50% cut-off ranging from 0.1 to 10 μm in aerodynamic diameter.
The mass size distribution of Atmospheric aerosol particles was unimodal with peak at 1.0~2.5 μm or 0.5~1.0 μm. The annual average concentrations of TSP, PM10, PM2.5, PM1, PM0.5 and PM0.1 were 44.0 μg/m3, 40.3 μg/m3, 31.4 μg/m3, 18.0 μ g/m3, 8.2 μg/m3, 3.0 μg/m3, respectively. On average PM10, PM2.5, PM1, PM0.5 and PM0.1 make up 0.91, 0.70, 0.41, 0.19 and 0.07 of TSP, respectively. The annual average of PM2.5/PM10 ratio was 0.77.
Ambient particulate matters(PM10 and PM2.5) were investigated at GNTECH university in Jinju city. Samples were collected using a dichotomous sampler(series 240, Andersen Corp.) and a TEOM(Tapered Element Oscillating Microbalance) monitor period from November 2012 to October 2013. For the dichotomous sampler measurements, daily 24-h integrated PM2.5 and PM10–2.5 ambient air samples were collected at a total flow rate of 16.7 L /min. For the TEOM monitor measurements, daily 1-h integrated PM10 ambient air samples were collected at a flow rate of 16.7 L /min. The annual average concentrations of PM10-2.5 and PM2.5 by a dichotomous sampler were 10.0±6.1 μg/m3 and 22.6±9.3 μg/m3, respectively. And PM10 concentration by dichotomous sampler were similar to TEOM monitor by 32.7±12.9 μg/m3 and 31.7±11.3 μg/m3, respectively. And good correlation (R2=0.964) between the two methods was observed. The annual average of PM2.5/PM10 ratio was 0.70±0.12.
The number concentrations, the mass concentrations and the elemental concentrations of PM10 have measured at Gosan site in Jeju, Korea, from March 2010 to December 2010. And the correlation and the factor analysis for the number, the mass and the elemental concentrations of PM10 are performed to identify their relationships and sources. The average PM10 number concentration is observed 246 particles/㎝3(35.7∼1,017 particles/㎝3) and the average PM10 mass concentration is shown 50.1 ㎍/㎥(16.7∼441.4 ㎍/㎥) during this experimental period. The number concentrations are significantly decreased with increasing particle size, hence the concentrations for the smaller particles less than 2.5 ㎛(PM2.5) are contributed 99.6% to the total PM10 number concentrations. The highest concentration of the 20 elements in PM10 determined in this study is shown by S with a mean value of 1,497 ng/㎥ and the lowest concentration of them is found by Cd with a mean value of 0.57 ng/㎥. The elements in PM10 are evidently classified into two group based on their concentrations: In group 1, including S>Na> Al>Fe>Ca>Mg>K, the elemental mean concentrations are higher than several hundred ng/㎥, on the other hand, the concentrations are lower than several ten ng/㎥ in group 2, including Zn>Mn>Ni>Ti>Cr>Co>Cu>Mo>Sr>Ba>V >Cd. The size-separated number concentrations are shown positively correlated with the mass concentrations in overall size ranges, although their correlation coefficients, which are monotonously increased or decreased with size range, are not high. The concentrations of the elements in group 1 are shown highly correlated with the mass concentrations, but the concentrations in group 2 are shown hardly correlated with the mass concentrations. The elements originated from natural sources have been predominantly related to the mass concentrations while the elements from anthropogenic sources have mainly affected on the number concentrations of PM10.
This study analyzed mass concentrations of TSP, PM10 and PM2.5 and elemental constituents according to the isentropic backward trajectories of air parcel from Cheongwonin East Asia during the period January – October, 2011. Mass concentrations of the continental polluted airflow (CP) showed levels of TSP and PM10 mass concentrations higher than the continental background airflow (CB). Also, PM2.5 mass concentrations of anthropogenic fine particles ran higher in CP than in CB. The elemental constituents and elemental constituent ratio ended up varying depending on the origin of atmospheric aerosols generated. The average absolute content of elemental constituents reached its height in CB, the ratio of anthropogenically originating elements (PE) among the all elements (AE) analyzed marked a high in CP, and Mg+Na/AE reached its height in the oceanic airflow (OA). At the same time, TSP, PM10 and PM2.5 mass concentrations, the ratio of PM2.5/TSP and PE/AE element ratio ran higher in CP than CB. Episodes of large-scale transport of atmospheric pollutants as observed at Cheongwon were 8 cases and 22 days. The ratios of PM10, PM2.5 among TSP mass concentrations showed different results and the ratios of PM2.5 showed an increasing trend in the episodes of anthropogenic air pollution transport. Overall, dustfall episodes show a level of elemental constituents higher than those of anthropogenic air pollution.Dustfall episodes were observed to contain more of Fe, Al and Ca originating from continental soils and those of air pollution were observed to contain more of Zn, Mn, Cu and Pb. By difference in contents of absolute elemental constituents, episodes of anthropogenic air pollution showed a high PE/AE rate, and dustfall episodes a high SE/AE rate.
The objective of this study was to examine and compare to transient response to quantitative and hydraulic shocks which produce equal changes in mass rate of organic feed in aerobic fixed-film process. The general experimental approach was to operate the system at several growth rates under steady-state(pre-shock) conditions, then to apply step changes during day 3 in dilution rate(hydraulic shock), or feed concentration(quantitative shock) at the same organic mass loading rate. Performance was assessed in both the transient state and the new steady-state (post-shock). Shock load of different type did not produced equivalent disruptions of effluent quality for equal increases on mass loading rate. Based on effluent concentrations, a hydraulic and a quantitative shock at the same mass loading caused equal increase in total effluent COD, but the increase was primarily a result of suspended solids the hydraulic shock and COD in the quantitative shock, The time which effluent COD came to peak values were about 32∼48 hours at the low organic loads and 52∼72 hours at the high organic loads, respectively. A quantitative shock produced a much greater increase in effluent COD than did a hydraulic shock at the same mass loading. Mean and peak values of effluent concentration were increased in 2.8∼4.2 times at low organic loading rate, 5.2∼6.6 times at the high organic loading rate respectively.