• Journal of Korean Society for Atmospheric Environment
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• v.32 no.1
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• pp.67-81
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• 2016

In order to examine the variation characteristics of chemical compositions in accordance with the different meteorological conditions, $PM_{10}$ and $PM_{2.5}$ were collected at Gosan site of Jeju Island in 2014, and then their ionic and elemental species were analyzed. The concentrations of nss-$SO{_4}^{2-}$ and $NH_4{^+}$ were respectively 4.3 and 3.3 times higher in fine particle mode ($PM_{2.5}$) compared to coarse particle mode ($PM_{10-2.5}$), however $NO_3{^-}$ concentration was 1.6 times higher in coarse mode compared to fine particle mode. During Asian dust days, the concentrations of nss-$Ca^{2+}$ and $NO_3{^-}$ increased highly as 7.7 and 4.5 times in coarse particle mode, and 3.0 and 4.9 times higher in fine particles, respectively. Especially, the concentrations of the crustal species (Al, Fe, Ca, K, Mn, Ba, Sr, etc.) indicated a noticeable increase during the Asian dust days. For the haze days, the concentrations of secondary pollutants increased 2.2~2.7 and 2.9~6.0 times in coarse and fine particles, respectively, and they were 0.8~1.1 and 1.8~2.4 times, respectively, during the mist days. The aerosols were acidified largely by sulfuric and nitric acids, and neutralized mainly by ammonia in fine particle mode during the haze days, but neutralized by calcium carbonate in coarse particle mode during the Asian dust days. The clustered back trajectory analysis showed that the concentrations of nss-$SO{_4}^{2-}$, $NO_3{^-}$, and $NH_4{^+}$ were relatively high when the inflow pathway of air mass was from the southern part of China.

• Journal of the Korean Society of Industry Convergence
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• v.20 no.4
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• pp.339-343
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• 2017

Masks are a portable functional product for daily use. They can protect user health by filtering harmful fine particles in the air. In the past decade, there have been approximately 10 yellow dust incidences per year, amounting to a total duration of 20 days, and they continue to increase year after year. In addition, the frequency of yellow dust incidences in Korea has increased by more than four times compared to levels from the 1970s. Statistical reports indicate that annual damages caused by yellow dust amount to more than six trillion KRW. This study developed a zero-fog multi-layer mask with a collection efficiency and yellow dust and particulate matter filtration areas that are at least thrice as effective as existing masks. The new mask also reduces pressure drag by half.

• Journal of Korean Society for Atmospheric Environment
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• v.20 no.1
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• pp.33-46
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• 2004

Air pollutants were measured eight times from June 1999 to June 2002 on regular ferries cruising across the Yellow Sea between Incheon in Korea and Qingdao or Tianjin in China. PM$_{10}$ and PM$_{2.5}$ were measured as particulate matters and SO$_2$, CO, and NO$_{x}$ were measured as gaseous pollutants. On each route, sampling was made, starting two hour after departure and ending two hour before arrival. Low concentrations of gaseous pollutants that were not much varied according to sampling period and location revealed that atmosphere over the sea was not directly affected by anthropogenic emissions. However, concentrations of fine particles were generally higher than those measured at Deokjeok Island, 50km west of the western seashore, at similar periods. It was believed that considerable influence of China in the form of secondary pollutants was exerted over the sea.a.a.a.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.05b
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• pp.305-307
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• 2003

우리가 숨쉬고 있는 대기 중에는 많은 부유 먼지가 존재하고 있으며, 이는 산업활동의 증가와 도시화, 차량 수 등의 증가로 인하여 그 종류와 농도가 크게 변화하여 자연 생태계 및 인체 건강에 심각한 영향과 피해를 유발시키고 있다(1989; 1996). 이러한 부유 먼지는 거대먼지(coarse particle)와 미세먼지(fine particle)로 분류할 수 있다. 미세먼지에는 여러 가지 금속성분, 유기물질,virus, 조류 및 곰팡이 등이 포함되어 있으며, 다환 방향 족 탄화수소(polycyclic aromatic hydrocarbon, PAH) 등의 발암성 물질이 포함되어 있다. (중략)

• Applied Microscopy
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• v.8 no.1
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• pp.49-52
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• 1978

Mask cells are distributed in the animal tissue, The bat subject has not been studied with the electron microscope, The material was fixed in 2.5% phosphate buffered glutaraldehyde for 24 hours at $4^{\circ}C$ and then post-fixed in phosphate buffered 1% osmium tetroxide for 2 hours at $4^{\circ}C$ and then the cleared tissues were embedded in Epon. The mast cell has numerous cytoplasmic processes projecting into the surrounding connective tissue. In general, the cytoplasmic granules showed ovoid, round, lunal or irregular shape, most of them were fine particulate substructure in texture. Especially, the granules was enclosed by the lamella structure.

• Transactions of the Korean Society of Automotive Engineers
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• v.4 no.5
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• pp.179-186
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• 1996

The magnetic fibrous polymeric oil filter for automotive was obtained by pneumoextrusion processing prepared from thermoplastic polymer(polyamide) containing magnetic particulate filer (Ba ferrite), and treated subsequently in a magnetic fields. Using an oil filter tester and particle quantifier, the dependence of filtrational characteristics of the magnetic oil filter on the parameters of mean pore sizes and magnetic properties were analyzed. Also experimental engine-bed test of oil filters was investigated. The magnetic fibrous polymeric filter was shown to possess a highly filtration efficiency in filtering the fine metal particles with increasing the magnetic force of filter element. In this study, we knew that efficiency of magnetic fibrous polymeric filter was dependent on the magnetic strength of the filter elements.

• Journal of Korean Society for Atmospheric Environment
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• v.16 no.2
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• pp.103-112
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• 2000

Elemental carbon(EC) and organic carbon(OC) in fine particles (PM2.5) were collected from October 1995 through August 1996 in the Chongju area. The annual mean concentrations of EC and OC were 4.44 and 4.99 $\mu\textrm{g}$/m3 respectively. EC showed seasonal variation (p<0.01) The magnitude of the seasonal mean EC concen-tration progresses in the following manner : fall>winter>spring>summer. However OC was not statistically seasonal difference(p=0.20) The annual average OC/EC ratio was 1.12 suggesting that organic carbon measured may by emitted directly in particulate form(primary aerosol) The contribution of EC to PM2.5 mass follows a general pattern in which fall(14.6%) > winter (9.8%) >spring(7.8%) =summer(7.8%) and the contribution of OC to the PM2.5 mass varies in order fall(13.8%) >winter(11.3%) >spring(10.5%) >summer (9.4%) Total carbona-ceous particles(EC and OC) accounted for 17-28% of the PM2.5 mass.

• Tribology and Lubricants
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• v.12 no.3
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• pp.39-47
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• 1996

The magnetic fibrous polymeric oil filter elements for industrial lub-systems were obtained by pneumoextrusion processing prepared from thermoplastic pqlymer (polyamide) containing a magnetic particulate filler (Ba ferrite), and treated subsequently in a magnetic fields. Using the standard laboratory oil filtration test rig, metallic particle quantifier and image analyser system, the dependence of filtration charateristics of the magnetic filter media on the parameters of porosity and magnetic properties was investigated. The pressure drops and efficiencies of lubricating filter elements were measured on the packing density and magnetised filler content of filter element. Also, the industrial lub-systems such as lubricant filters for gear test rig and electric discharge processing machine were used for testing the flitrational characteristics of tl, c magnetised filter elements. The magnetic fibrous polymeric filter material was shown to possess a highly filtration efficiency in filtering the fine ferrous particles with increasing the magnetic force of filter element. Therefore, it is expected that the magnetic fibrous polymeric filter material should be used for effective oil filrers on the industrial lub-systems.

• Journal of Korean Society for Atmospheric Environment
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• v.11 no.3
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• pp.221-231
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• 1995

산업발달에 따라 불가피하게 생성되며, 대기오염의 주종을 이루면서 인체에 가장 유해한 분진입자는 산업체의 오일(oil) 및 석탄연소 보일러, 자동차, 제철/제강 및 시멘트 플랜트 등으로 부터 배출되는 미세입자(fine particle)들이며, 앞으로 이들의 제어에 관한 연구가 지속적인 관심의 대상이 될 것이다. 한 예로, 석탄연소 화력발전소로부터 1$\mum$ 이하의 입자들의 배출량은 무게비로는 1% 이하이지만 입자수의 비율에서는99%를 차지하고 있다. 이들은 매우 높은 중금속 함유량을 지니고 있기 때문에 인체의 호흡시 심각한 문제를 유발시킬 뿐만 아니라, 이러한 미세입자들은 대기중에 부유하고 있다가 비(rain)에 의하여 세정되어 수질오염까지도 유발시킨다. 1992년 2월 공포된 대기환경보전법 시행규칙에 따라 분진배출 허용기준이 장기 입법예고 되므로서 1995년 1월과 1999년 1월의 2단계에 걸쳐 현재 적용 받고 있는 분진배출 규제치보다 훨씬 낮은 선진국 수준의 분진배출 규제가 요구되고 있으며, 분진이 배출되는 인근지역주민의 민원에 대처하기 위해서는 연돌로부터 분진배출이 눈에 감지되지 않을 정도까지 분진배출농도를 관리해야할 필요성이 높아지고 있다. 이에 따라 집진장치의 효율도 중유전소 Boiler 의 경우는 90% 이상, 석탄전소 Boiler의 경우는 99.5% 이상의 고효율이 요구되고 있다.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2002.04a
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• pp.35-36
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• 2002

대기중에 존재하는 가스상ㆍ입자상 오염물질은 그 형태와 발생원, 함유물질 등이 매우 다양하며, 특히 산성가스와 에어로졸은 스모그 현상의 원인물질로서 수명단축과 가시도(Visibility) 감소의 원인으로 작용하여 건강에 직ㆍ간접적인 피해를 주고있어 대기질 관리의 주요 대상이 되고 있다. 미세입자(PM$_{2.5}$)는 시정장애에 영향을 미치고(Chow et al., 1993; Conner et al., 1991), PM$_{10}$보다도 호흡기 계통의 사망률에 더 큰 영향을 미친다고 보고되고 있다(Reichhardt, 1995). (중략)략)