• Title/Summary/Keyword: 초미세입자

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Temporal trend in size distribution of ultrafine particles in source and receptor sites of the Los Angeles Basin (미국 LA 지역 오염발생지와 영향권에서의 초미세입자 크기분포에 대한 시간적 고찰)

  • ;Si Shen;Constantinos Sioutas;Yifang Zhu;William Hinds
    • Proceedings of the Korea Air Pollution Research Association Conference
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    • 2002.04a
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    • pp.39-40
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    • 2002
  • 대기 중 초미세입자 (0.1 마이크론 이하)들을 최근 건강 위해성에 대한 연관성이 추정됨에 따라 도시지역 초미세입자에 대한 다각적인 연구의 필요성이 증대하고 있다. 초미세입자들은 전체 질량농토에 대한 그 기여도가 매우 낮아 수 농도와 크기분포에 의하여 보다 잘 표현되지만 도시지역 초미세입자의 수 농도 크기분포에 대한 자료는 아직 부족한 실정이다. (중략)

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Particle path and performance evaluation of differential mobility analyzer (Differential Mobility Analyzer(DMA)내의 입자운동 및 특성 분석)

  • An, Gang-Ho;Kim, Nam-Hyo;Lee, Jong-Ho;Bae, Gwi-Nam
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.20 no.6
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    • pp.2005-2013
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    • 1996
  • Particle paths and flow fields in a prototype differential mobility analyzer (DMA) were numerically analyzed solving Navier-Stokes equation, electric field equation and particle motion considering viscous drag force, Coulomb force and polarization force. Analytically predicted particle diameters for the prototype DMA are in good agreement with the measured particle diameters within $\pm$1%. And the analytically predicted particle diameters are also in good agreement with numerical results for the prototype DMA.

Mineralogical characterization of the dust storm in spring of 2002 at Seoul, Korea (2002년 봄 서울지역 황사의 광물특성)

  • 이성록;김기현
    • Proceedings of the Korea Air Pollution Research Association Conference
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    • 2003.05b
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    • pp.409-410
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    • 2003
  • 2002년 봄철 기간 중 한반도지역에서 관측된 황사는 전례를 찾기 어려울 정도로 고농도의 분진량을 기록하였다. 따라서 이 기간 중에는 전국 각지에 산재한 다수의 초등학교가 임시휴교령을 내려야 하였을 정도로 황사현상의 영향이 대단히 심각하였다. 본 연구진은 서울시 북동부 지점의 관측점으로부터 초미세입자 (PM2.5) 및 미세입자 영역 (PM10)의 부유상입자물질을 황사기간 (3월)과 비황사기간 (4월)에 걸쳐 채집하였다. (중략)

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Preparation of cobalt oxide(Co3O4·CoO) ultra fine particles using cobalt(II) chloride hexahydrate and crystalline cellulose as a starting materials (Cobalt(II) chloride hexahydrate와 결정성 셀룰로오스를 출발물질로 사용한 산화코발트(Co3O4·CoO) 초미세입자의 합성)

  • Soo-Jong Kim
    • The Journal of the Convergence on Culture Technology
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    • v.9 no.3
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    • pp.587-592
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    • 2023
  • Cobalt oxide (Co3O4·CoO) ultra fine particles were synthesized by liquid phase precursor method. cobalt(II) chloride hexahydrate (CoCl2·6H2O) was as a starting material. A plant-derived crystalline cellulose was used as impregnating materials. A impregnated precursor was calcined at a temperature of 350 to 900℃ to obtain cobalt oxide particles having a particle size of 1 to 10㎛. The crystallization process and morphology according to the calcination temperature were examined, and the properties of the synthesized powder were evaluated using SEM and XRD. It was confirmed that a crystal phase of Co3O4 began to form around 350℃ and crystal growth occurred up to 900℃. At a temperature above 500℃, the Co3O4 crystal was changed to another crystal phase CoO.

Study on the Contribution of Mixing Effects in Sampling Tube and Condensation Nuclei Counter(CNC) to the measurement of size distribution obtained using Differential Mobility Analyzer and CNC (Differential Mobility Analyzer(DMA)와 Condensation Nuclei Counter(CNC)를 이용한 입자크기 분포 측정에서 샘플링 튜브와 CNC에서의 혼합 효과가 입자 크기 분포 측정에 미치는 영향에 관한 연구)

  • Lee, Youn-Soo;Ahn, Kang-Ho
    • Proceedings of the KSME Conference
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    • 2001.06d
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    • pp.104-109
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    • 2001
  • The time to measure the size distribution using Condensation Nuclei Counter(CNC) and Differential Mobility Analyzer(DMA) can be shortened by classifying particles ramping the DMA voltage exponentially and continuously. In measurement, particles sampled at different time are mixed together going through sampling tube and CNC. Because the size distribution is inversed by using detector responses to sampling time intervals in this accelerated method, the mixing effects give inversion errors to the size distribution. The mixing effects can be considered by appling the transfer function with mixing effects to the data inversion. The inversion considering this effects gives birth to the size distribution shifted to the opposite direction of the size scanning.

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Monitoring of Airborne Fine Particle using SMPS in Ansan Area (SMPS(Scanning Mobility Particle Sizer)를 이용한 안산지역 대기중 초미세입자(30\~500nm) 분포연구)

  • Kim Yong-min;Ahn Kang-Ho
    • Journal of Korean Society for Atmospheric Environment
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    • v.21 no.3
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    • pp.295-301
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    • 2005
  • The fine particles in the range of $30\~500nm$ are monitored at Hanyang University campus in Ansan using house made DMA (differential mobility analyzer) and commercial CPC (condensation particle counter, TSI inc.) in SMPS mode. The monitoring period is March 16th 2004 through May 7th, 2004. During the monitoring period, Aitken nuclei mode $(30\~100nm)$ particle concentration has a tendency of increase in the morning and evening hours. However, the accumulation mode $(100\~500nm)$ particle concentration stays rather stable than that of Aitken mode.