• Title/Summary/Keyword: sticking coefficient

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Sticking Coefficient in Bi-thin Film Prepared by IBS Method

  • Yang, Sung-Ho;Park, Yong-Pil;Chun, Min-Woo;Park, Sung-Gyun;Park, Woon-Shik
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2000.07a
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    • pp.193-197
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    • 2000
  • BSCCO thin films are fabricated via a co-deposition process by an ion beam sputtering with an ultra-low growth rate, and sticking coefficients of the respective elements are evaluated. The sticking coefficient of Bi element exhibits a characteristic temperature dependence : almost a constant value of 0.49 below 73$0^{\circ}C$ and decreases linearly with temperature over 73$0^{\circ}C$. This temperature dependence can be elucidated from the evaporation and sublimation rates of bismuth oxide, Bi$_2$O$_3$, from the film surface. It is considered that the liquid phase of the bismuth oxide plays an important role in the Bi(2212) phase formation in the co-deposition process.

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Evaluation of Sticking Coefficient in BSCCO Thin Film Fabricated by Co-sputtering

  • Lee, Hee-Kab;Park, Yong-Pil;Lee, Kwon-Hyun;Lee, Joon-Ung
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.13 no.1
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    • pp.80-84
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    • 2000
  • BSCCO thin films are fabricated via a co-deposition process by an ion beam sputtering with an ultra-low growth rate, and sticking coefficients of the respective elements are evaluated. The sticking coeffi-cient of Bi element exhibits a characteristic temperature dependence : almost a constant value of 0.49 below 73$0^{\circ}C$ and decreases linearly with temperature over 73$0^{\circ}C$. This temperature dependence can be elucidated from the evaporation and sublimation rates of bismuth oxide, Bi\ulcornerO\ulcorner, from the film surface. It is considered that the liquid phase of the bismuth oxide plays an important role in the Bi(2212) phase formation in the co-deposition process.

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Analysis of Sticking Coefficient in BSCCO Superconductor Thin Film Fabricated by Co-deposition (공증착법으로 제작한 BSCCO 초전도 박막의 부착계수 해석)

  • 안인순;천민우;박용필
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2001.11a
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    • pp.300-303
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    • 2001
  • BSCCO thin films are fabricated via a co-deposition process by an ion beam sputtering with an ultra-low growth rate, and sticking coefficients of the respective elements are evaluated. The sticking coefficient of Bi element exhibits a characteristic temperature dependence : almost a constant value of 0.49 below 730$^{\circ}C$ and decreases linearly with temperature over 730$^{\circ}C$. This temperature dependence can be elucidated from the evaporation and sublimation rates of bismuth oxide, Bi$_2$O$_3$, from the film surface. It is considered that the liquid phase of the bismuth oxide plays an important role in the Bi 2212 phase formation in the co-deposition process.

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Measurement of Real Outgassing Rate using Double Conductance Method (이중 콘덕턴스법에 의한 실기체방출률 측정)

  • 인상렬
    • Journal of the Korean Vacuum Society
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    • v.5 no.3
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    • pp.175-180
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    • 1996
  • Double conductance method is proposed as an effectvie way to measure real outgassing rates of materials regardless of their adsorbing power. The real outgassing rate and the sticking coefficient of the CFC (carbon fiber composite) which is used widely as the material for armor plates infusion experiment devices were obtained by adopting this method. At $40^{\circ}C$ the real ougassing rate was $Pa, m^3/s.m^2$(in $N_2$ equivalent), which was higher than 5 times the measured one, and the sticking coefficient was about 0.018($H_2O\; and \;H_2$ were the main residual gases).

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Influence of surface roughness and porosity on the hydrogen sorption speed of getter (표면 거칠기 및 다공도가 게터의 수소 흡착속도에 미치는 영향)

  • In S. R.
    • Journal of the Korean Vacuum Society
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    • v.14 no.4
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    • pp.171-179
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    • 2005
  • The influence of the surface roughness and the porosity on the apparent sticking coefficient of the getter was determined quantitatively by Monte Carlo simulation. The sorption characteristics of the getter was investigated by solving numerically the particle balance equation depending on the sticking probability and diffusivity.

Sticking Characteristics in Bi2Sr2CanCun+1Ox Thin Films Fabricated by using the Evaporation Method to Improve the Sticking Ratio (부착율 개선을 위해 증발 법으로 제작한 Bi2Sr2CanCun+1Ox 박막의 부착 특성)

  • 천민우;박용필
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.16 no.11
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    • pp.1029-1034
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    • 2003
  • The Bi$_2$Sr$_2$Ca$_{n}$Cu$_{n+1}$ O$_{x}$, superconducting thin films arc fabricated by using the sputtering and evaporation method. Because we confirmed the sticking ratio of Bi element in the Bi$_2$Sr$_2$Ca$_{n}$Cu$_{n+1}$ O$_{x}$ superconducting thin film fabricated by using the sputtering method was much lower than the expected value, to get the enough number of the flakes of Bi, faraday cup was used to evaporate Bi clement. As a result of the fabrication, Bi 2201 and Bi 2212 single phases could be made by the optima of deposition condition. And we confirmed the sticking coefficient of Bi element was clearly related to the temperature change of the substrate and the generation of Bi22l2 phase

Quantification of Bacterial Attachment-related Parameters in Porous Media

  • Park, Seong-Jik;Lee, Chang-Gu;Kim, Song-Bae
    • Environmental Engineering Research
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    • v.13 no.3
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    • pp.141-146
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    • 2008
  • Transport of Escherichia coli ATCC 11105 through porous media was investigated in this study using two sets of column experiments to quantify the attachment-related parameters (sticking efficiency, attachment rate coefficient and filter factor). The first set of experiments was performed in quartz sand under different ionic strength conditions (1, 20, 100, 200 mM) while the second experiments were carried out in quartz sand mixed with metal oxyhydroxide-coated sand (0, 5, 10, 25%). The breakthrough curves of bacteria were obtained by monitoring effluent, and then bacterial mass recovery and attachment-related parameters were quantified from these curves. The first experiments showed that the mass recoveries were in the range of 13.3 to 64.7%, decreasing with increasing ionic strength. In the second experiments, the mass recoveries were in the range of 15.0 to 43.4%, decreasing with increasing coated sand content. The analysis indicated that the sticking efficiency, attachment rate coefficient and filter factor increased with increasing ionic strength and coated sand content. The value of filter factor in the first experiments ranged from 1.45 e-2 to 6.72 e-2 1/cm while in the second experiments it ranged from 2.78 e-2 to 6.32 e-2 1/cm. Our filter factor values are one order of magnitude lower than those from other studies. This discrepancy can be attributed to the size of sand used in the experiment. The analysis demonstrated that the travel distance of bacteria estimated using the filter factor can be varied greatly depending on the solution chemistry and charge heterogeneity of porous media.

Study on the Vibrational Scraping of Uranium Product from a Solid Cathode of Electrorefiner (진동 탈리에 의한 전해정련 고체음극에서의 우라늄 생성물 회수 연구)

  • Park, Sungbin;Kang, Young-Ho;Hwang, Sung Chan;Lee, Hansoo;Paek, Seungwoo;Ahn, Do-Hee
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.13 no.4
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    • pp.315-319
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    • 2015
  • A high-throughput electrorefiner has been developed for commercialization use by enhancing the uranium recovery from the reduced metal which is produced from the oxide reduction process. It is necessary to scrap and effectively collect uranium dendrites from the surface of the solid cathode for high yield. When a steel electrode is used as the cathode in the electrorefining process, uranium is deposited and regularly stuck to the steel cathode during electrorefining. The sticking coefficient of a steel cathode is very high. In order to decrease the sticking coefficient of the steel cathode effectively, vibration mode was applied to the electrode in this study. Uranium dendrites were scraped and fell apart from the steel cathode by a vibration force. The vibrational scraping of the steel cathode was compared to the self-scraping of the graphite cathode. Effects of the applied current density and the vibration stroke on the scraping of the uranium dendrites were also investigated.

Dynamics of Hydrogen on Si (100)

  • Boland, John J.
    • Proceedings of the Korean Vacuum Society Conference
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    • 2000.02a
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    • pp.25-25
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    • 2000
  • In this talk we discuss the dynamics of hydrogen on the Si(100)-2xl surface. At room temperature the sticking coefficient for molecular hydrogen on this surface is less than 10sup-12. However, hydrogen molecules desorbing from the surface do not have an excess of energy, suggesting at best a small barrier on the exit channel. These observations have led to speculation about the validity of detailed balance in this system. Here we show that this discrepancy can be explained by considering both the surface-molecule co-ordinate and that associated with the Si-Si dimer bond tiltangle. By preparing the surface dimers with a specific tiltangle we demonstrate that the barrier to adsorption is a function of this angle and that the sticking coefficient dramatically increase for certain angles. The adsorption-desopption dynamics can then be described in terms of a common potential energy hypersurface involving both of these co-ordinates. The implications of these observations are also discussed. The dynamics of adsorbed hydrogen atoms on the Si(100) surface is also described. Paired dangling bonds produced following recombinative hydrogen desorption are mobile at elevated temperatures. Pairs of dangling bonds are observed to dissociate, diffuse, and ultimately recombine. At sufficiently elevated temperatures dangling bond exchange reactions are observed. These data are analyzed in terms of an attractive zone and an effective binding interaction between dangling bonds. Insights that this provides into the nature of surface defects and the localized chemistry that occurs on this surface, are also discussed.

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Influence of constraint MgO deposition onto phosphors on luminance properties in AC Plasma Display Panels

  • Jeoung, Jin-Man;OH, P.Y.;Moon, M.W.;Lee, J.H.;Jeong, J.E.;Lee, H.J.;Han, Y.K.;Lee, S.B.;Jeong, S.H.;Yoo, C.K.;Yoo, N.R.;Choi, E.H.;Ko, B.D.
    • 한국정보디스플레이학회:학술대회논문집
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    • 2005.07b
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    • pp.1215-1217
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    • 2005
  • One of the important problems in recent AC-PDP technology is the image sticking. In this research, we have investigated the PDP cell with constraint deposition MgO on phosphor, the electrical and optical properties in the PDP cell were examined. Also, we have investigated the correlation with image sticking and degraded MgO protective layer, phosphor in AC-PDP. As a result, we measured the secondary electron emission coefficient ${\gamma}$, discharge characteristics and Brightness for the constraint degraded phosphor are compared with those of nondegraded phosphor.

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