• Title/Summary/Keyword: paricle-size distribution

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An Analysis of Characteristics of Particulate Matter Exhausted from Diesel Locomotive Engines (디젤기관차 엔진에서 배출되는 입자의 특성분석)

  • 박덕신;김태오;김동술
    • Journal of Korean Society for Atmospheric Environment
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    • v.19 no.2
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    • pp.133-143
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    • 2003
  • Numerous evidence have been reported that fine particulate matters can play an important role in threatening human health. Recently concerns on fine particle pollution from various engines may require re-examination of particulate emission standards. The particles emitted by most diesel engines are mainly divided into their size ranges such as Dp< 50 nm and 50 nm< Dp< 1,000 nm. In this work, the number concentration and the size distribution of fine particles emitted from an exhaust manifold of a railroad diesel engine were measured under load test conditions using a scanning mobility particle sizer (SMPS). The fine particles observed were within the range of 7 to 304 nm under different load conditions with two different dilution ratios. The fine particles exhibited unique patterns showing bimodal shapes in size distribution.

Size Distribution of Water-Soluble Ionic Components in the Atmospheric Aerosols Collected in Jeju City, Korea (제주시 대기부유부진 중 수용성 이온성분의 입경별 분포특성)

  • Hu Chul-Goo;Song Jeong-Hwa;Lee Ki-Ho
    • Journal of Environmental Science International
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    • v.13 no.12
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    • pp.1067-1078
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    • 2004
  • Atmospheric particulate matters were collected by 8-stage non viable cascade impactor from October 2002 to August at Jeju City. Eight water-soluble ionic components $(Na^+,\;NH_{4}_{+},\;K^+,\;Ca{2+},\;Mg^{2+},\;CI^-,\;NO_{3}^-\;and\;SO_{4}^{2-})$ were analyzed by Ion Chromatography. The concentration of particulate matters and eight water-soluble ionic components were determined to investigate their size distributions. Particulate matters exhibited a tri-modal distribution with peak value around $0.9,\;4.0{\mu}m\;and\;9.5{\mu}m.$ In summer, the last peak value was lower than other season values likely due to particulate matter scavenged by rain water. Four ionic components $(Na^+,\;Ca^{2+},\;Mg^{2+}\;and\;CI^-)$ exhibited a bi-modal distribution in the coarse mode whereas three ionic components $(NH_{4}^+,\;K^+\;and\;SO_{4}^{2-})$ in the fine mode, with maximum peak value around $0.9{\mu}m.\;NO_{3}^-$ was found in both the coarse and the fine mode. The enrichment factor (E.F.) of each ionic components was calculated. Based upon E.F., it is considered that $Na^+,\;CI^-,\;and\;K^+$ in coarse paricle mode were delivered form oceanic source, but other components might have other source origins.