• Title/Summary/Keyword: high concentration distribution

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Developing a Method for Detecting the Asian dust event Among High $PM_{10}$ events Using Aerodynamic Particle Sizer (APS) (Aerodynamic Particle Sizer (APS)를 이용한 고농도 $PM_{10}$ 사례 중 황사 판별기법 개발)

  • Lee, Young-Gon;Cho, Chun-Ho;Kim, Myoung-Soo
    • Atmosphere
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    • v.18 no.1
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    • pp.25-32
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    • 2008
  • Log normalized volume size distribution (dV/dlog$D_p$) with 52 size ranges from 0.5 to $20.0{\mu}m$ was measured for the cases of high $PM_{10}$ mass concentration (> $200{\mu}gm^{-3}$) using the Aerodynamic Particle Sizer (APS) at the Korea Global Atmosphere Watch Center (KGAWC) from 6 April, 2006 to 5 April, 2007. Black Carbon (BC), gaseous pollutants of $NO_X$ and $SO_2$ and ${\AA}ngstr\ddot{o}m$ exponent were also measured to examine the properties of the volume size distribution. From distinct difference of the high volume concentration (> $100{\mu}m^3cm^{-3}$), the volume size distribution for each event day was clasified into four types: (1) Type 1 had the high volume concentration for supermicron particles from 2.3 to $6.0{\mu}m$ and maximum average volume concentration was $160.7{\mu}m^3cm^{-3}$ at $3.5{\mu}m$. (2) Type 2 represented the high volume concentration in the both size range of submicron ($0.7-1.0{\mu}m$) and supermicron particles ($2.1-4.1{\mu}m^3cm^{-3}$ and $136.2{\mu}m^3cm^{-3}$ were found at 0.8 and $3.3{\mu}m$ respectively. (3) Type 3 showed the high volume concentration in the size range of $0.5-3.5{\mu}m$ and highest volume concentration of $201.1{\mu}m^3cm^{-3}$ at the particle size bin of $0.8{\mu}m$. (4) Type 4 was characterized by the high volume concentration for the fine particles less than $1.2{\mu}m$ and very high concentration of $446.8{\mu}m^3cm^{-3}$. ${\AA}ngstr\ddot{o}m$ exponent, concentration of gaseous ($NO_X$ and $SO_2$), and particle (BC) pollutants suggested that Type 1 was a typical volume size distribution for the Asian dust and Type 3 provided transportation of air pollutants. The distribution in Type 2 found to have both characteristics of the Asian dust and air pollutants, and Type 4 was took place during the foggy atmosphere containing high density of local pollutants. Based on the properties of volume size distribution, we can identify the three major events contributing the increase of $PM_{10}$ mass concentration, and hope to provide a guideline for discriminating the Asian dust from high $PM_{10}$ events. More case studies and longeto advance this determination method.

Numerical Simulation of $NO_2$Concentration considering SST Effects (SST 효과를 고려한 계절별 $NO_2$농도 수치모의)

  • 원경미;이화운;김유근
    • Journal of Environmental Science International
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    • v.10 no.3
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    • pp.187-194
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    • 2001
  • For the purpose of predicting air pollutants concentration in Pusan coastal urban, we used an Eulerian model of flow and dispersion/chemistry/deposition process considering SST effects which estimate through POM. The results of air quality model including emission from various sources show that the seasonal variation pattern of respective pollutants was affected by the seasonal SST fields and local circulation. Horizontal deviation of diurnal SST was 2.5~4K, especially large gradients in coastal region. Through numerical simulation of wind fields we predicted that local circulation prevailed during daytime in summer and nighttime in winter. So high concentration distribution showed toward inland in spring and summer seasons, while high concentration distribution showed at inland near coast in autumn and winter.

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Characteristics of Urban Aerosol Number Size Distribution in Seoul during the Winter Season of 2001 (2001년 겨울철 서울 대기 에어로졸의 입경별 수 농도 특성)

  • 배귀남;김민철;임득용;문길주;백남준
    • Journal of Korean Society for Atmospheric Environment
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    • v.19 no.2
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    • pp.167-177
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    • 2003
  • The number size distribution of urban aerosols ranging from 0.02 to 20 ${\mu}{\textrm}{m}$ in diameter was measured by using a scanning mobility particle sizer (SMPS) system and an aerodynamic particle sizer spectrometer (APS) at Seoul from November 30,2001 to January 14, 2002. The gaseous species such as CO, NO, NO$_2$, and $O_3$ were also continuously monitored. The daily average concentration of urban aerosols sorted into three groups (0.02~0.1 ${\mu}{\textrm}{m}$, 0.1~1 ${\mu}{\textrm}{m}$ and 1~10 ${\mu}{\textrm}{m}$) and the typical number, surface, and volume distributions of urban aerosols were discussed in this paper. The weekly variation of aerosol concentration was compared with those of gaseous concentrations. relative humidity, and visibility. The results showed that the particle number concentration seemed to increase in the morning and the number concentration of fine particles less than 1 fm in diameter seemed to increase when the concentrations of CO, NO, and NO$_2$ were high. The number concentration of fine particles was relatively high when the relative humidity was greater than 70% during the increasing period of relative humidity. The visibility was weakly correlated with the concentration of aerosols ranging 0.1 to 1 ${\mu}{\textrm}{m}$, and the number size distribution for high visibility episode was apparently different from that for low visibility episode.

Characteristics of Concentration Distribution of Coastal Urban Air Pollutants (연안 도시 대기오염 물질의 농도분포 특성)

  • 박종길;석경하;김지형;차주완
    • Journal of Environmental Science International
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    • v.11 no.12
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    • pp.1243-1252
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    • 2002
  • This paper aims to find the characteristics of concentration distribution of coastal urban air pollutants. For this purpose, It was used the daily meteorological data and the hourly concentration data for $O_3$and NO$_2$ in Busan metropolitan city from 1994 to 1996. It was investigated the annual and monthly distribution of ozone and nitrogen dioxide concentration at each site in Busan, and also investigated the characteristics of concentration change of air pollutants with time under the sea breeze. As a results, the concentration of nitrogen dioxide and ozone tend to be increased every year and nitrogen dioxide concentration is higher than ozone concentration at all sites in Busan. The concentration of ozone is high in summer season and low in winter season, but the concentration of nitrogen dioxide have a reversed trend. The monthly peak concentration of ozone occurred in April and September, while the monthly minimum concentration of nitrogen dioxide occurred in August. Their trend were identified by sites near the coastline than sites stands apart from the coastline. The sea breeze occurred annual mean 81 day in Busan from 1994 to 1996. The main wind direction of sea breeze was classified into southwesterly and southeasterly. In case of southwesterly, It was pronounced the south wind and southwest wind. In case of southeasterly, the occurrence frequency of east wind was high. Especially, the concentrations of urban air pollutants, such as ozone and nitrogen dioxide, were high on time which the sea breeze flow, and the areas that ozone concentration was high moved from outside part to central part of city with time. In costal urban such as Busan, the wind direction of sea breeze is influenced the change of ozone and nitrogen dioxide concentration on time which the sea breeze flow at each site and also influenced the change of air pollutants concentration of sites on the pathway of sea breeze.

The Analysis of Spatial Distribution of Ozone in the Southern Coast of Korea using the Aircraft (2009, Summer) (항공기를 이용한 남해안 지역의 오존 공간분포 조사 (2009년, 여름철))

  • Seo, Seok-Jun;Kim, So-Young;Lee, Min-Do;Choi, Jin-Soo;Kim, Su-Yeon;Lee, Seok-Jo;Kim, Jeong-Soo;Lee, Gang-Woong
    • Journal of Korean Society for Atmospheric Environment
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    • v.28 no.1
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    • pp.12-21
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    • 2012
  • The purpose of this study is to understand distribution of ozone concentration in the south coastal region of Korea by evaluating ozone spatial distribution in the upper air using aircraft. Sampling was carried out from May to August in 2009. The average concentration of ozone in the upper air was ranged from 32.3~90.8 ppb with its maximum concentration of 132 ppb. When it comes to the spatial distribution of ozone, ambient concentration was high in the air, 1,000 m and 500 m above the southern sea near the Gwangyang Bay area and emission sources, respectively. Daily mean concentration of NOy was 6.7~24.2 ppb and that of CO was 0.152~0.487 ppm. In addition, the concentration was appeared to be relatively high in the upper air of industrial regions and the southern seas. Meanwhile, the concentration of both $NO_y$ and CO was high in the upper air of the emission sources regardless of latitude. As for PAN, its daily mean concentration ranged between 0.1 and 0.6 ppb with overall mean concentration of 0.2 ppb. The average concentration of VOCs was 48 ppb, and the concentration of toluene and m,p-Xylene were higher than other components.

The Analysis of Atmospheric Flow Field and Air Quality According to the High Level Ozone Case on Gwangyang Bay (광양만 권역에서의 고농도 오존 사례에 대한 기상 및 대기질 분석)

  • Choi, Hyun-Jung;Lee, Hwa-Woon;Leem, Heon-Ho;Song, Jae-Hwal
    • Journal of Environmental Science International
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    • v.17 no.7
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    • pp.743-753
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    • 2008
  • Gwangyang Bay is often severely confronted by photochemical pollutants due to its location and dense emissions. It is located in a basin on the south coast of the Korean peninsula and is crossed by a remarkable cluster of hills and mountains of a small horizontal scale that forms a channel. Clearly, the air flow field has a great influence on the dispersion of air pollutants. The characteristics of the wind flow patterns have an important effect on the dispersion of pollutants emitted. In these situations, the distribution of the ozone concentration is extremely complicated because of the superposition of circulations of the air flow fields, especially in complex coastal region. In this study, we examined the distribution of the high level ozone on Gwangyang Bay particularly during the episode day (for 5 years). Among these days, A high level ozone was induced by the development of a sea/land breeze local circulation system, as well as by an anabatic/catabatic flow from the mountains and valley with weakening of the synoptic wind. High level ozone distribution pattern(6 types) on Gwangyang bay is analyzed and the comparison of each pattern reveals substantial localized differences in intensity and distribution of ozone concentration from the site coherence and UPA analysis of ozone concentration. The observed VOC concentration had much difference in concentrations and daily variations between Jungdong and Samil.

Uranium Distribution Patterns and U-mineral in the U-bearing Coaly Slate of Ogcheon System (옥천계(沃川系) 함(含)우라늄 탄질암중(炭質岩中)의 우라늄의 존재상태(存在狀態)와 광물종(鑛物種))

  • Lee, Min Sung;Kim, Sang Wook
    • Economic and Environmental Geology
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    • v.18 no.2
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    • pp.135-138
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    • 1985
  • The radioautographing of U-bearing cloaly slate samples were initiated in order to clarify the uranium distribution patterns in the samples of Ogcheon system. Moreover, x-ray powder diffraction and x-ray single crystal analysis studies were undertaken to identify the uranium mineral which was extracted from U-bearing coaly slate. The handspecimens were collected from the Boseong mine, located in Deokpyeong area, Goesan-gun, Chungcheongbug-do. According to the experimental studies, it has been found the following facts: (1) fixed carbon has close relation with uranium contents, (2) quartz veins developed in U-bearing coaly slate are diveded into two groups based on mode of occurrence, formation stage and uranium distribution pattern; early quartz vein ($QV_1$) with low uranium concentration and late quartz vein ($QV_2$) with high uranium concentration, (3) matrixes around $QV_1$ are displayed homogeneous and high uranium concentration, while matrixes around $QV_2$ are low uranium concentration, (4) uranium mineral is identified as a variety of autunite.

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Organ Distribution of Total mercury, Organicmercury, Zinc and Copper in Methylmercury-Administered Rats (유가수온($CH_{3}$ HgCl) 투여시 흰쥐의 각 장기별 중금속 (유기수온, 총수은, 아연, 구리) 분포)

  • 이진헌;김영규;정문호
    • Journal of Environmental Health Sciences
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    • v.17 no.2
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    • pp.127-139
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    • 1991
  • Four group(Control I II, Treatment I II ) of Rats, each consisting of 10 rats, were studied Methylmercury Chloride MMc was orally given to Sprague-Dawley male at does of 10mg/kg (5 mg/kg $\cdot$ day), 10mg/kg after two weeks. This study was designed to investigate the distribution, the difference and the ratio of organic mercury, total mercury, zinc and copper in tissue, in each others group. The result were as follows: 1. There was no significantly difference in the body weight between two groups( p > 0.05). 2. There was significantly difference in the distribution of zinc concentration in liver, kidndey, blood, spleen between control I and treatment I, and in blood, spleen between control II and treatment II (P < 0.05). 3. There was significantly difference in the distribution of copper concentration in kidney, blood between control I and treatment I, and in spleen brain between control II and treatment II. 4. The ratio of zinc concentration in treatment/control was high at spleen. 5. The ratio of methylmercury/totalmercury was high at spleen.

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Characterization of Nanoparticles from Welding and Grinding Processes: Evaluation of Number Concentration and Size Distribution (용접 및 연마에서 발생되는 나노입자 특성 평가 : 수농도 및 입경분포 분석)

  • Kim, Boowook;Kim, Hyunwook
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.22 no.3
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    • pp.184-190
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    • 2012
  • Objectives: This study aimed to characterize the nanoparticles produced by welding and grinding processes. Methods: The number concentrations of particles were mapped to determine the distribution of welding fumes in a workplace atmosphere using a hand-held condensation particle counter. An electrical low-pressure impactor was used for measuring the number concentration and particle size distribution. Results: High number concentrations were found around arc cutting and welding (grinding) processes. In the worker's breathing zone, the mean number concentration was 655,000 particles/cm3 and the count median diameter (CMD) was 84 nm with several multi peak distributions (~20, 70, 300 nm). However, at a distance of 3 m from the welding position, the number concentration decreased to 153,000 particles/cm3 with a 70 nm single peak size distribution. During a grinding process, peaks with high concentrations of nanoparticles were temporarily observed. The mean number concentration was 1,520,000 particles/cm3, and the CMD was 30 nm. Nanoparticles (<100 nm) made up 58% and 92% of the aerosols produced by welding and grinding processes, respectively.

Characteristics of Concentration and Size Distribution of PAHs of Total Suspended Particulates in urban air (도시대기부유분진중 다환방향족 탄화수소의 농도 및 입경분포 특성)

  • 조기철;이승일;김달호;허귀석;김희강
    • Journal of Korean Society for Atmospheric Environment
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    • v.10 no.1
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    • pp.57-63
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    • 1994
  • In order to comprehension of the behaviour of PAHs in air which is known as carcinogens and/or mutagens suspended Particulates in ambient air were collected by Anderson air sampler from 1992. 6 to 1993. 5 in Seoul. Ten species of PAHs( Phen, An, Fl, R, Py, BaAn, BaP, Chry, BeP, DiB(a, h)An, I123p) were analyzed to understand monthly variations of PAHs distribution of PAHs concentration according to particle size, and correlation between PAHs and independent charactierstics of PAHs The highest concentration of TSP was 155.58$\mu\textrm{g}$/㎥ in May and the lowest was 60$\mu\textrm{g}$/㎥ in August. Concentration of TSP was more affected by coarse particles in spring, otherwise which was more affected by fine particles in winter. According to results of anaylsis of samples that were collected by Anderson air sampler, concentration of PAHs was more high in winter than that in summer. In almost samples collected by Anderson air sampler, concentration of PAHs was more high in coarse particles than in fine particles, but BaP well known as carcinogenic matter had more high concentration in fine particles(56-97.5%) than that in coarse particles(2.5-46%). Correlation between concentrations of TSP and PAHs was more high in fine Particles than in coarse Particles. Both fine particles and coarse particles have negative correaltion with radiation.

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