• 제목/요약/키워드: Cleaning Efficiency

검색결과 407건 처리시간 0.032초

RF/DC 방전을 이용한 고 진공용SUS 용기세정에 관한 연구 (A study on the RE/DC discharge cleaning for high vacuum SUS chamber)

  • 김정형;임종연;서인용;정광화
    • 한국진공학회지
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    • 제10권3호
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    • pp.298-302
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    • 2001
  • 초청정을 요구하는 진공용기의 내벽세정을 위한 RF 및 DC 방전세정장치를 제작하여 여러 가지 방전조건에 따라 세정효과를 조사하였다. Baking없이 방전세정만을 수행하였을 때는 baking만 진행했을 때와 비슷한 세정효과를 나타내었으며 세정후의 탈기체율은 반으로 줄어들었다. Baking과 방전세정을 동시에 진행하면 세정효과가 매우 증대되어 세정후의 탈기체율이 1/20으로 감소하였다. Baking과 방전세정을 동시에 수행 시 여러 방전조건에 따른 세정효과를 조사하였는데 이온이 진공용기 내벽에 부딪히며 세정을 할 때 이온에너지와 이온밀도가 중요한 역할을 하는 것으로 보였다. 진공용기를 세정함에 있어 RF방전세정이 DC 방전세정보다 효과적이라는 결과를 얻었다.

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파장이 다른 레이저의 임플란트 세정 효과에 관한 연구 (Study on Implant Cleaning Effect of Lasers of Different Wavelengths)

  • 박은경;양윤석;이가람;유영태
    • 한국생산제조학회지
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    • 제22권4호
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    • pp.643-651
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    • 2013
  • This study applied a laser cleaning method (dry cleaning) that is used for cleaning semiconductor elements to dental implant cleaning. The lasers used in this study were pulsed fiber lasers with wavelengths of 1,064 and 532 nm. The peak output, energy per pulse, energy density per pulse, time of pulse experiment, and number of pulse experiments served as process variables for this study, and the variables were changed for each experiment. As a result, a laser with a wavelength of 532 nm showed much higher cleaning efficiency than its 1,064 nm counterpart. As the wavelength range decreased, the quantized energy increased and the reflection rate of the titanium used for the implant decreased; consequently, the energy absorption rate increased. Therefore, it is proposed that the energy density by wavelength has a greater influence on cleaning than does the output size.

Chemical cleaning effects on properties and separation efficiency of an RO membrane

  • Tu, Kha L.;Chivas, Allan R.;Nghiem, Long D.
    • Membrane and Water Treatment
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    • 제6권2호
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    • pp.141-160
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    • 2015
  • This study aims to investigate the impacts of chemical cleaning on the performance of a reverse osmosis membrane. Chemicals used for simulating membrane cleaning include a surfactant (sodium dodecyl sulfate, SDS), a chelating agent (ethylenediaminetetraacetic acid, EDTA), and two proprietary cleaning formulations namely MC3 and MC11. The impact of sequential exposure to multiple membrane cleaning solutions was also examined. Water permeability and the rejection of boron and sodium were investigated under various water fluxes, temperatures and feedwater pH. Changes in the membrane performance were systematically explained based on the changes in the charge density, hydrophobicity and chemical structure of the membrane surface. The experimental results show that membrane cleaning can significantly alter the hydrophobicity and water permeability of the membrane; however, its impacts on the rejections of boron and sodium are marginal. Although the presence of surfactant or chelating agent may cause decreases in the rejection, solution pH is the key factor responsible for the loss of membrane separation and changes in the surface properties. The impact of solution pH on the water permeability can be reversed by applying a subsequent cleaning with the opposite pH condition. Nevertheless, the impacts of solution pH on boron and sodium rejections are irreversible in most cases.

Nanosecond Laser Cleaning of Aluminum Alloy Oxide Film

  • Hang Dong;Yahui Li;Shanman Lu;Wei Zhang;Guangyong Jin
    • Current Optics and Photonics
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    • 제7권6호
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    • pp.714-720
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    • 2023
  • Laser cleaning has the advantages of environmental protection, precision, and high efficiency, and has good prospects for application in removing oxide films on the surface of aluminum alloy. This paper discusses the cleaning threshold and cleaning mechanism of aluminum alloy surface oxide film. A nanosecond pulsed laser was used to remove a 5-㎛-thick oxide film from the surface of 7A04 aluminum alloy, and the target surface temperature and cleaning depth were simulated. The effects of different laser energy densities on the surface morphology of the aluminum alloy were analyzed, and the plasma motion process was recorded using a high-speed camera. The temperature measurement results of the experiment are close to the simulation results. The results show that the laser cleaning of aluminum alloy oxide film is mainly based on the vaporization mechanism and the shock wave generated by the explosion.

고층건물 외벽 유지보수 건설로봇 시스템 개발을 위한 청소공정 작업절차 분석 (Facade Cleaning Process Analysis For Construction Robot System Design of High-rise Building External wall Maintenance)

  • 김대건;김복규
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2011년도 춘계 학술논문 발표대회 2부
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    • pp.77-79
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    • 2011
  • As residents and building owners demand maintenance that is required to achieve sustainable building performance, efficient building management methods are required. Even though the demand for maintenance systems is increasing, current maintenance work for high-rise buildings mostly uses conventional ropes and gondolas that pose a high risk of accidents and exhibit poor performance and efficiency. Thus, there is an urgent need to develop an automation robot system that can reduce accidents and improve the maintenance efficiency of the conventional high-rise building façade maintenance system. As a preceding work for the development of an automation robot system, this study classified and analyzed the work processes of actual construction sites and proposed basic techniques for the work mechanisms of the robot system by investigating the motions of cleaning workers.

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