• Title/Summary/Keyword: 조대입자

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Measurement of Coarse Particle Mass in Alumina Powders Using Wet Sieve Method (습식 체분리법을 이용한 알루미나분말 중의 조대입자 함량평가)

  • Jung, Sang-Jin;Lim, Hyung-Mi;Lee, Seung-In;Kim, Young-Hee;Kim, Soo-Ryong;Cho, Yong-Ick
    • Journal of the Korean Ceramic Society
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    • v.39 no.8
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    • pp.775-782
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    • 2002
  • The effects of solid and dispersant concentration was investigated by wet-sieving method for knowing the amount of coarse particle in fine powders. In the work alumina powders, sodium hexametaphosphate and sodium polyacrylate were used for preparing slurry. It was confirmed that the coarse particle mass increased by increasing alumina concentration and decreasing dispersant concentration. With systematic measurements we know that the alumina powder and dispersant of one weight percent(1.0wt%) were proper quantity for coarse particle mass measuring, respectively. Sodium polyacrylate as dispersant showed higher coarse particle mass than sodium hexametaphosphate. The sieve mass was decreased according to increase of experiment number. Based on experiments it was considered that wet-sieving method is good tool for measuring a coarse particle mass in fine powders.

Characterization and source apportionment by factor analysis of water soluble ions in atmospheric particles in Cheonan, Korea (천안시 대기 입자 중 수용성 이온성분의 계절적 특성 및 요인분석을 통한 오염기여도 평가)

  • Oh, Se-Won
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.12 no.2
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    • pp.1020-1026
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    • 2011
  • Seasonal characteristics of water soluble ions in atmospheric particles in Cheonan were studied between 2008 and 2009. $Na^+$, $NH_4^+$ and $NO_3^-$, $SO_4^{2-}$ were the principle cations and anions in both coarse and fine particles. Water soluble ions occupied 24.4%(spring), 33.2%(summer), 40.7%(fall), and 39.6%(winter) of the total mass of coarse particles. In fine particles, 43.0%(spring), 59.7%(summer), 55.4%(fall), and 53.2%(winter) of mass were occupied by water soluble ions. From the factor analysis, 2 and 4 factors were extracted for water soluble ions in coarse and fine particles, respectively. 70.33% of water ions in the coarse particles were estimated from the natural source, but 66.01% in the fine particles were from the anthropogenic source.

Elemental concentrations of atmospheric particles in Cheonan during 2006 (2006년 천안시 대기 입자의 원소 성분 특성)

  • Oh, Se-Won
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.9 no.6
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    • pp.1782-1786
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    • 2008
  • To investigate the characteristics of elemental components of atmospheric particles in Cheonan, atmospheric particles were sampled using a high volume air sampler equipped with a 5-stage cascade impactor during 2006. 16 elemental concentrations in fine and coarse particles were determined using ICP-AES and ICP-MS. The total mass concentrations of fine and coarse particles were 33.23 and $20.66{\mu}g/m3$, respectively, and the total elemental concentrations were 1.27, $1.71{\mu}g/m3$, occupying 3.8 and 8.3% of the total mass. Fe, Al, Ti were the most abundant elements in both fine and coarse particles, and the total Pb concentration was 84.55ng/m3, below the National standard. Enrichment factor for Sc, Cr, Cu, Zn, As, Se, Sn, Pb in fine particles were above 1,000. This indicates that the elements in fine particles are mainly from the anthropogenic sources including automobiles.

Characteristics of Elemental Composition of $PM_{2.5}$ Aerosols Measured at Gosan, Jeju (제주 고산에서 측정한 $PM_{2.5}$ 에어로졸의 원소성분 특성연구)

  • 류성윤;김정은;정현록;김영준;한진석;문광주;공부주;안준영
    • Proceedings of the Korea Air Pollution Research Association Conference
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    • 2003.05b
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    • pp.133-134
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    • 2003
  • 대기 중에 부유하고 있는 입자상 물질은 보통 입경에 따라 2.5$\mu\textrm{m}$ 이하의 미세입자와 2.5$\mu\textrm{m}$ 이상의 조대입자로 나눌 수 있다. 조대입자는 토양 및 해염, 꽃가루, 화산재 및 토양 먼지와 같이 자연발생원에서 주로 생성되며, 인체에 큰 영향을 미치지 않는다. 그러나 미세입자는 화석연료의 연소, 자동차의 배출가스 및 화학물질의 제조공정 등의 인위적 발생원에서 주로 방출되며, 또한 이들 1차 생성분진과는 달리 대기중에서 황산가스나 휘발성 유기화합물 둥이 응축과정을 거쳐 가스상에서 입자상으로 변환되어 생성된 2차 입자도 환경학적으로 매우 중요한 의미를 갖는다. (중략)

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Comparison of Chemical Characteristics of Fine Particulate in Seoul Area (일부 서울지역 미세먼지의 화학적 조성에 관한 연구)

  • 이홍석;김윤신;박태술;이종태;조용성;이상복
    • Proceedings of the Korea Air Pollution Research Association Conference
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    • 2001.11a
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    • pp.231-232
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    • 2001
  • 도시지역의 주 오염물질 중 하나인 입자상 물질(Particulate Matter:PM)은 공기역학적 직경 2.5$\mu\textrm{m}$을 기준으로 이산형 분포를 하여 2.5$\mu\textrm{m}$이하를 미세입자, 2.5$\mu\textrm{m}$이상을 조대입자로 나뉜다. 이 미세입자는 주로 자동차 배출, 산업연소에서 배출되는 가스상 물질의 2차 반응으로 발생한다(Pope et al., 1995). 미세입자는 상당량이 2차 반응에서 생성되는 물질이며, 크기가 작은 대신 상대적으로 표면적이 크기 때문에 각종 중금속과 유해 대기오염물질과의 흡착이 용이하여 호흡기 계통의 질병을 일으킬 수 있는 확률이 조대입자에 비해 높다고 알려져 있어 인체에 미치는 영향이 클 것으로 시사되고 있다(Dockery et al., 1998). (중략)

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Compositions of haze aerosols and their variation by inflow pathway of air mass at Gosan site in Jeju Island during 2012-2013 (연무 에어로졸의 조성 및 기류 유입경로별 변화: 2012-2013년 제주도 고산지역 측정)

  • Hyeon, Dong-Rim;Song, Jung-Min;Kim, Ki-Ju;Kim, Won-Hyung;Kang, Chang-Hee;Ko, Hee-Jung
    • Analytical Science and Technology
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    • v.27 no.4
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    • pp.213-222
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    • 2014
  • The atmospheric aerosols of $PM_{10}$ and $PM_{2.5}$ were collected at Gosan site of Jeju Island during 2012- 2013. Their ionic and elemental species were analyzed in order to examine the composition variation of the haze aerosols in accordance with the pathway of air mass. The concentrations of $nss-SO_4{^{2-}}$, $NO_3{^-}$, and $NH_4{^+}$ increased 2.1~3.7 times in coarse particle and 3.1~6.5 times in fine particle modes, respectively, showing especially high $NO_3{^-}$ concentrations in fine particles during the haze days. The concentrations of S, Zn, Pb and K increased 3.0~5.6 times in coarse particles and 3.2~7.7 times in fine particles during the haze days, on the other hand Al, Fe, and Ca concentrations were high only in coarse particles. Due to the back trajectory analysis, the concentrations of $nss-SO_4{^{2-}}$ and $NO_3{^-}$ for haze days were high when the inflow pathway of air mass was from China, especially a high increase of $NO_3{^-}$ as through the south of China. The $NO_3{^-}/nss-SO_4{^{2-}}$ concentration ratio was relatively high in coarse mode as air mass inflow from China, but in fine mode it was high as air mass passing through the Korean peninsula.

Composition comparison of PM10 and PM2.5 fine particulate matter for Asian dust and haze events of 2010-2011 at Gosan site in Jeju Island (황사와 연무 시 PM10 및 PM2.5 미세먼지 조성 비교: 2010-2011년 고산지역 측정)

  • Kim, Ki-Ju;Lee, Seung-Hoon;Hyeon, Dong-Rim;Ko, Hee-Jung;Kim, Won-Hyung;Kang, Chang-Hee
    • Analytical Science and Technology
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    • v.27 no.1
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    • pp.1-10
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    • 2014
  • The $PM_{10}$ and $PM_{2.5}$ samples were collected at Gosan Site of Jeju Island, and analyzed, in order to investigate the size distribution and pollution characteristics of their components. $NH{_4}{^+}$, nss-$SO{_4}^{2-}$, $K^+$, and $CH_3COO^-$ were mostly existed in fine particles. Meanwhile, $NO{_3}{^-}$ was distributed in both fine and coarse particles, and $Na^+$, $Cl^-$, $Mg^{2+}$, nss-$Ca^{2+}$ were rich in coarse particle mode. The concentrations of nss-$Ca^{2+}$ and $NO{_3}{^-}$ were increased 36.7 and 3.2 times in coarse particles, and 15.0 and 3.1 times in fine particles during the Asian Dust periods. Especially, the concentrations of crustal elemental species such as Al, Fe, Ca, K, Mg, Ti, Mn, Sr, Ba were highly increased for those periods. In the haze events, the concentrations of secondary air pollutants were increased 1.3~2.6 and 1.5~4.2 times in coarse and fine particles, respectively. Moreover, the remarkable increase of $NO{_3}{^-}$ concentration was also observed in fine particle mode. The factor analysis showed that the composition of coarse particles was influenced mainly by marine sources, followed by soil and anthropogenic sources. On the other hand, the fine particles were influenced by anthropogenic sources, followed by marine and soil sources.

Acidification and neutralization characteristics of size-fractionated atmospheric aerosols at Gosan site of Jeju Isalnd (제주도 고산지역 대기 에어로졸의 입경별 산성화-중화 특성)

  • Kim, Won-Hyung;Song, Jung-Min;Kim, Hyeon-A;Kang, Chang-Hee;Kim, In-Whan
    • Analytical Science and Technology
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    • v.28 no.1
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    • pp.47-57
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    • 2015
  • The size fractionated atmospheric aerosols have been collected at Gosan site of Jeju Island during 2010~2011, and then their characteristics of acidification and neutralization have been investigated. The anthropogenic $NH_4{^+}$ and nss-$SO_4{^{2-}}$ showed high concentrations mostly at ultra-fine particle mode of $0.7{\sim}1.1{\mu}m$, but they also had a bimodal distribution showing high concentrations at coarse particle mode of $4.7{\sim}5.8{\mu}m$ during Asian Dust periods. The concentrations of nss-$Ca^{2+}$ and $NO_3{^-}$ were relatively high at coarse particle mode of $3.3{\sim}4.7{\mu}m$, especially $NO_3{^-}$ showed high concentrations with a bimodal pattern at both fine and coarse particle modes. The acidification of atmospheric aerosols at Gosan area was contributed mostly by inorganic sulfuric and nitric acids, while the contribution by organic formic and acetic acids was only 1.6~6.4%. Furthermore, the neutralization of acidic species among atmospheric aerosols was performed mostly by $NH_3$, $CaCO_3$ and $MgCO_3$, especially the neutralization by $NH_3$ was high in fine particle mode, while that by $CaCO_3$ was relatively high in coarse particle mode.

The Metallic Composition of PM2.5 and PM10 in a Northeast Region of Seoul During the Spring 2001 (2001년 봄철 서울시 북동부지점에서 관측한 중금속성분의 농도분포)

  • Choi, Gyoo-Hoon;Kang, Chang-Hee;Kim, Ki-Hyun
    • Journal of the Korean earth science society
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    • v.23 no.6
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    • pp.514-525
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    • 2002
  • The analysis of heavy metals associated with both PM2.5 and PM10 fraction of aerosols was made from a northeast region of Seoul during the spring period of 2001. The mean concentrations of fine (PM2.5), coarse (PM10-PM2.5), and PM10 fraction were observed as 49.3${\pm}$29.2, 50.5${\pm}$35.0, and 95.5${\pm}$46.1 ${\mu}g$/m$^3$, respectively during this study period. According to the results of enrichment factor (EF) analysis between different particle fractions, major elements (including Fe, Ca, Na, and K) were found to exhibit EF values of less than 10. However, heavy metal components (like Zn and Pb) showed very high EF values. Comparison of fine/coarse (F/C) concentration ratio showed that Zn, Cr, Pb, and Ni have higher ratio values than others. The metallic composition of particles was also compared on both absolute and relative terms. The results of our analysis showed an evidence that the increase in the total metallic contents is prominent during the spring period due mostly to the Asian Dust event.