• 한국재료학회:학술대회논문집
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• 한국재료학회 1998년도 IUMRS-ICEM ABSTRACT BOOK
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• pp.47.2-47
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• 1998

• 한국안전학회지
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• 제9권4호
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• pp.132-136
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• 1994

The new spray system is proposed by using a pipe with hygroscopic needle electrode In order to develop an air-cleaning ESP with high collection efficiency for submicron particles and high removal efficiency for NOx, SO$_2$, NH$_3$. Fundamental characteristics of charging water spray, which is not an usual wet type, are investigated experimentally. As a result, corona discharging mode and ozone generation rate are significantly affected by the operational conditions, such as the applied voltage and wet condition of the needle electrode.

• Asian Journal of Atmospheric Environment
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• 제8권2호
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• pp.89-95
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• 2014

There have been a lot of efforts to keep permissible emission standards and to reduce the amount of emitted air pollutants. There are several air pollution control equipments, however, wet scrubber is used to remove particulate matters and gaseous pollutants simultaneously, even if it has low collection efficiency in the particle size less than $5.0{\mu}m$. To overcome this problem, we introduced a spray tower scrubber with an electrospray system which a high voltage was indirectly applied. We found that collection efficiency of fine particles in the electrospray system was improved by increasing electrical field strength and the ratio of liquid-gas flow rate (from 41% to 84% for $0.3{\mu}m$ particles). In addition, a number of small droplets generated from an electrospray system led high collection efficiency, resulting from electrostatic attraction between droplets and particles and higher collision frequency. Therefore, we can conclude that the introduction of an electrospray system is quite effective to increase the particle removal efficiency of a spray tower scrubber.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2006년도 제27회 추계학술대회논문집
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• pp.30-33
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• 2006

Onset voltage plays a crucial role in the design of a spray microthruster. This paper presents an analytical electrostatic model to predict the behavior of onset voltage in an array of emitters. The basic idea of this method is to superimpose the electric potentials obtained from each individual emitter in an array of emitters. The results show that if one emitter operates and the other neighboring emitters are dry, the potential required for cone-jet spraying generally increases as the emitter spacing decreases (due to electrical shielding). However at very close spacing the potential can decrease. If all emitters operate at the same time, the phenomenon that even at very close spacing the onset voltage required for cone-jet spraying increases merely as the emitter spacing decreases.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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• pp.254-255
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• 2006

Powder library of pseudo four components Li-Ni-Co-Ti compounds were prepared for exploring the composition region with the single phase of the layer-type structure by using combinatorial high-throuput preparation system "M-ist Combi" based on electrostatic spray deposition method. The new layer-type compounds were found wider composition region than the previous report. This process is promising way to find multi component functional materials.

• Safety and Health at Work
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• 제8권3호
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• pp.296-305
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• 2017

Background: Surfactant-containing water sprays are commonly used in coal mines to collect dust. This study investigates the dust collection performance of different surfactant types for a range of coal dust particle sizes and charges. Methods: Bituminous coal dust aerosol was generated in a wind tunnel. The charge of the aerosol was either left unaltered, charge-neutralized with a neutralizer, or positively- or negatively-charged using a diffusion charger after the particles were neutralized. An anionic, cationic, or nonionic surfactant spray or a plain water spray was used to remove the particles from the air flow. Some particles were captured while passing through spray section, whereas remaining particles were charge-separated using an electrostatic classifier. Particle size and concentration of the charge-separated particles were measured using an aerodynamic particle sizer. Measurements were made with the spray on and off to calculate overall collection efficiencies (integrated across all charge levels) and efficiencies of particles with specific charge levels. Results: The diameter of the tested coal dust aerosol was $0.89{\mu}m{\pm}1.45$ [geometric $mean{\pm}geometric$ standard deviations (SD)]. Respirable particle mass was collected with $75.5{\pm}5.9%$ ($mean{\pm}SD$) efficiency overall. Collection efficiency was correlated with particle size. Surfactant type significantly impacted collection efficiency: charged particle collection by nonionic surfactant sprays was greater than or equal to collection by other sprays, especially for weakly-charged aerosols. Particle charge strength was significantly correlated with collection efficiency. Conclusion: Surfactant type affects charged particle spray collection efficiency. Nonionic surfactant sprays performed well in coal dust capture in many of the tested conditions.

• 한국결정성장학회지
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• 제20권2호
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• pp.69-73
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• 2010

정전분무증착 기술에 의해 증착된 고체산화물 연료전지(SOFC) 양극재료인 SSC 양극막의 미세구조적 변화에 대해 연구하였다. Samarium chloride hexahydrate$(SmCl_3{\cdot}6H_2O)$, strontium chloride hexahydrate$(Co(No_3)_2{\cdot}6H_2O)$, cobalt nitrate hexahydrate$(Co(No_3)_2{\cdot}6H_2O)$의 출발 물질과 용매로써 메탄올이 전구체 용액을 제조하는데 사용되었다. SOFC의 양극을 위해 적합한 다공성의 SSC 막을 제조하였으며, 그 미세구조가 증착시간, 기판온도, 인가전압 등과 같은 공정변수들에 의존한다는 것을 관찰하였다. 주사전자현미경과 X-ray 회절 패턴이 미세구조와 결정성 분석을 위해 사용되었다. 본 연구를 통해, ESD 기술이 요구하는 상의 합성과 다공성의 미세구조를 갖는 SOFC의 양극막을 제조하는데 효과적인 방법임을 입증하였다.

• 센서학회지
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• 제13권5호
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• pp.335-341
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• 2004

A light collecting probe named Multi-colored Integrated Receiving Optics (MICRO) is experimentally examined to verify its performance. For these purposes, the time-series signals of MICRO probe is compared with those of electrostatic probe and light-guided probe by monitoring, for example, such as OH radical chemiluminescence, CH radical band and droplet Mie scattering. In addition, the experiment was conducted by using laminar premixed Bunsen flame, turbulent premixed Bunsen flame and premixed spray flame, respectively. It was confirmed that the performance of MICRO probe was very useful and convenient to obtain the chemiluminescence signals from local regions in turbulent premixed Bunsen flame and premixed spray flame.

• 한국표면공학회지
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• 제33권4호
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• pp.233-240
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• 2000

A novel electrostatic spraying method to solidify molten zinc coating layer was studied by SEM and measurement of sample's temperature. The sprayed droplets also served as nucleation sites in the solidification reaction of molten zinc but might leave the pitting mark by impinging on its surface especially at high spray pressure. Our experimental results showed that electric field could change the sprayed particle trajectories and assist the fine droplets to attach on the surface. Thus, by reducing the spray pressure and by applying the electric voltage higher than -20 KV to charge the droplets electrostatically, we could produce the spangle free galvanized coating layer without pitting.

• 한국생물환경조절학회:학술대회논문집
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• 한국생물환경조절학회 1998년도 임시총회 및 학술논문발표요지
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• pp.1-4
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• 1998

상온연무기와 같은 소량살포기에 의해 살포된 농약액의 입자경은 10-20$\mu\textrm{m}$ 이하의 것이 대부분이다. 미소 액적은 단시간에 공기의 습구 온도와 평형하게 되어 혼합, 확산되는 특성을 가지고 있으며 증발과 Drift현상이 발생된다. 시설원예의 경우 폐쇄환경에 있으므로 연무직후 온실내 작업의 제한, 부착력포의 불균일, 증발과 Drift량의 과다 등이 큰 문제가 된다. (중략)