• Environmental Engineering Research
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• 제7권3호
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• pp.159-167
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• 2002

• 한국대기환경학회지
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• 제19권2호
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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.

• 한국환경과학회지
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• 제13권12호
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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.