• Proceedings of the KSME Conference
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• 2000.04b
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• pp.404-409
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• 2000

Growth characteristics of silica particles have been studied experimentally using in situ sampling technique from $H_2/O_2TEOS$ diffusion flame with carefully devised sampling probe. Verification of sampling result was done through new method and effects of flame condition and TEOS flow rate on growth characteristics of silica particles were investigated. By comparing particles sampled by thermophoretic sampling in flame with those by collector sampling after probe, particles do not change before and after probe sampling, which was clearly proved from the fact that the result of TEM image analysis makes good agreement with that of SMPS measurement. As flame temperature increases, the effect of coalescence or sintering becomes important mechanism during growth of silica particles, resulting in canceling the effect of coagulation, which makes mean diameter of silica particles increase slowly. With increase in TEOS flow rate, the number concentration of generated silica particle increases but residence time of particles in flame decreases. As a result, there exists upper limit to which the diameter of silica particle increases under same flame condition.

• Proceedings of the KAIS Fall Conference
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• 2011.12b
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• pp.593-595
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• 2011

본 논문은 전산해석을 통하여 일반적으로 가솔린엔진에 적용되는 오일분리기의 성능을 분석하였다. 현재 상용화된 제품을 해석한 결과 Labyrinth부분에서는 포집 능력이 거의 없는 것을 확인하였다. 오일입자 포집효율이 전체적으로 분포되지 않고 5개의 작은 홀이 있는 격판 부분에서만 집중적으로 나타나는 것을 확인하였다. 또한, 일반적인 Cyclone형태의 오일분리기보다 압력강하량이 높은 것을 확인할 수 있었다.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2000.04a
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• pp.227-228
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• 2000

가상 임팩터(virtual impactor)는 가속노즐(acceleration nozzle)아래에 충돌판(impaction plate) 대신 가상의 공간을 가진 수집관(receiving tube)이 설치되어 유선의 방향이 $90^{\circ}$로 바뀔 때, 큰 입자는 유선에서 벗어나 수집노즐에 포집된다(Hounam and Sherwood, 1965). 가상 임팩터에는 관성 임팩터(inertial impactor)와는 다르게, 절단입경(cut-size)보다 큰 입자를 분리할 수 있는 부 유동(minor flow)과 절단입경보다 작은 입자를 분리할 수 있는 주 유동(major flow)으로 나눈다. (중략)

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.05a
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• pp.501-502
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• 2001

갯벌의 수질정화기능에 대하여 다양한 정의를 내릴 수 있으나 본 연구에서는 갯벌의 여과식성 저서생물에 의해 수중의 동ㆍ식물 플랑크톤과 데트리터스를 포함하는 입자성 유기물 (POM)이 포집되어 제거되는 기능으로 그 범위를 한정하였다. 갯벌생태계에서 수질정화기능의 핵심적 역할은 단연 이매패류가 담당하고 있다. 이들은 탁월한 여과능력으로 먹이 섭식과정에서 많은 양의 해수를 아가미로 걸러내기 때문에 결과적으로 수층의 입자성 유기물을 물리적으로 제거시키는 자연 여과시스템에 견주어진다. (중략)

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 1999.11a
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• pp.31-34
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• 1999

기-고체간의 접촉효율이 높고, 층 내 전체에 걸쳐서 균일한 기-고의 접촉을 갖는 등 많은 장점이 있어 석탄연소로, 촉매반응기와 같은 여러 기-고 반응기에 적용이 확대되고 있는 순환유동층은 높은 유속에서 조업되므로 상승관내 고체입자들은 즉시 비산하게 된다. 따라서, 원활한 반응에 필요한 상승관내 적절한 고체체류량 유지를 위해 고체입자들 대부분은 싸이클론에서 포집 되어 고체재순환부에 의하여 상승관내로 재주입 된다.(중략)

• Polymer(Korea)
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• v.31 no.3
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• pp.215-220
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• 2007

The control of the surface energy by electrohydrodynamic force provides electrospraying with various potential advantages such as simple particle size control, mono-dispersity, high recovery, and mild processing conditions. The advantages are quite helpful to improve the stability of protein drug and control its release. Herein, the nano-encapsulation of protein drugs using electrospraying was investigated. Albumin as a model protein was processed using uniaxial and co-axial electrospraying, and chitosan, polycaporlactone (PCL), and poly (ethylene glycol) (PEG) were used as encapsulation materials. The major processing parameters such as the conductivity of spraying liquids, flow rate, the distance of electrical potential gradient, etc were measured to obtain the maximum efficiency. In the chitosan systems, mean particles size decreases as flow rate and the distance between nozzle and the collecting part decreases. In the uniaxial technique of the PCL systems, mean particles size decreases as flow rate decreases. In the coaxial technique of the PCL systems, it was found that the particles size gets larger under the application of the higher ratio of inner-to-outer liquid flow rates. The primary particles formed out of an electrospraying nozzle showed narrow particle size distribution, but once they arrived to the collecting part, aggregation behavior was observed obviously. Efficient nano-encapsulation of albumin with PCL, PEG, and chitosan was conveniently achieved using electrospraying at above 12 kV.

• Proceedings of the KSME Conference
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• 2001.06d
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• pp.85-90
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• 2001

This work presents experimental results of filter media test by using particles from $0.02\;to\;0.6{\mu}m$ in diameter and by applying different charging states. In order to investigate the electret filter performance, the collection efficiency and the pressure drop of filter were measured. The face velocities of test filters varied from 2.4 to 20.4 cm/s. Another experiment setup for the cartridge cabin air filter was used to get an collection efficiency in submicron region. After charging level of electret filter severely decreased, the change of collection efficiency was verified. Experimental results show that the reliability of electret filters can be poor in some conditions.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.05b
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• pp.285-286
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• 2003

다단임팩터(cascade impactor)는 대기환경 연구에 있어 입자상물질의 물리ㆍ화학적 분석에 유용하게 사용되고 있는 입자상물질 포집장치이다. 본 연구그룹에서는 분리입경이 각각 10.07, 4.92, 2.49, 1.02, 0.7$\mu\textrm{m}$인 5단 다단임팩터를 이미 개발하여 성능평가를 수행하였으며, 그 연구결과를 발표하였다(Kwon et al., 2003). 또한 개발된 임팩터를 2002년 4월 8일 부터 29일까지 제주도 고산지역에서 실시된 ACE-Asia 측정 기간동안 설치 운영하여 대기 중 에어로졸 샘플링을 하였다(Park et al., 2003). 본 연구에서는 다단임팩터 사용자의 불편을 최소화하고, 장치의 상용화가 가능하도록 최적 설계에 주안점을 두었다. (중략)

• Proceedings of the Korea Air Pollution Research Association Conference
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• 1998.10a
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• pp.31-33
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• 1998

• Proceedings of the Korean Vacuum Society Conference
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• 2007.02a
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• pp.173-173
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• 2007