• Title/Summary/Keyword: ozone layer

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Characteristics of Ozone Advection in Vertical Observation Analysis Around Complex Coastal Area (연직관측자료를 통한 복잡 연안지역의 오존 이류특성)

  • Lee, Hwa-Woon;Park, Soon-Young;Lee, Soon-Hwan;Leem, Heon-Ho
    • Journal of Korean Society for Atmospheric Environment
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    • v.25 no.1
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    • pp.57-74
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    • 2009
  • In order to clarify the vertical ozone distribution in planetary boundary layer of coastal area with complex terrain, an observation campaign was carried out around Gwangyang Bay with dense pollutant emission sources during two days from June, 4 2007. For this observation are Radiosonde, SODAR(SOnic Detection And Ranging) and Tethered ozone sonde were employed. The surface meteorological and photochemical observation data provided by AWS (Automatic Weather System) and AQMS (Air Quality Monitoring System) were also applied for analysis. Synoptic condition is strongly associated with lower level ozone distribution in complex terrain coastal area. Since mesoscale circulation induced by difference of characteristics of land and sea and orographic forcing is predominant under calm synoptic condition, vertical distribution of ozone is complicate and vertical ozone concentration greatly fluctuated. However in second day when synoptic influence become strong, ozone concentration in lower levels is vertically uniform regardless of observation level. This results in vertical observation indicates that vertical ozone distribution is often determined by synoptic condition and also affects surface ozone concentration.

Epitaxial Growth of BSCCO Films by IBS Method (IBS법에 의한 BSCCO 박막의 에피택셜 성장)

  • 양승호;박용필
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2002.05a
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    • pp.627-630
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    • 2002
  • Bi$_2$Sr$_2$CuOx(Bi-2201) thin films were fabricated by atomic layer-by-layer deposition using an ion bean sputtering method. 10 wt% and 90 wt% ozone mired with oxygen were used with ultraviolet light irradiation to assist oxidation. XRD and RHEED investigations revealed that a buffer layer is formed at the early stage of deposition (less than 10 unit cell), and then c-axis oriented Bi-2201 grows on top of it.

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The Trade Regulation in the Multilateral Environmental Agreements on Climate Change (기후변화관련(氣候變化關聯) 국제환경협약체제하(國際環境協約體制下)의 무역규제조항(貿易規制條項))

  • Chung, Ye-Mo
    • THE INTERNATIONAL COMMERCE & LAW REVIEW
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    • v.14
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    • pp.349-370
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    • 2000
  • The environmental problems such as global climate change, global waming, ozone depletion, environmental pollution have been caused by the rapid economic growth, increasing in use of fossil fuels for industrialization and scientific technology development. Especially human activities are significantly altering the atomosphere's composition and its radiative properties. To Stabilize greenhouse gas concentrations in the atmosphere at a level that would prevent dangerous anthropogenic interference with the climate system, the international community adopted the UN Framework Convention on Climate Change in 1992 and Kyoto protocol in 1997. Also to protect ozone layer the international community adopted the Vienna Convention for the Protection of the Ozone Layer in 1985, and the Montreal Protocol on Substances that Deplete the Ozone Layer in 1987. To achieve global environmental objectives, some multilateral environmental agreements includes trade regulation. For example, Montreal Protocol includes the provisions to regulate the world trade of the sudstances which might destroy ozone layer. However Kyoto Protocol has no provisions to regulate trade and is not in force yet. Although there is no trade regulation article in Kyoto Protocol, the international world trade will be influenced by limitation and reduction of CO2 and strengthening the CO2 emission standard for import good. For example Korean car industy agreed with EU to reduce CO2 emission from new passenger car and Korean Semiconductor industry agreed with WSC(World Semiconductor Council) to reduce PFCs in 1999.

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A Study on the High Efficiency PR Strip technology by using the Ozone Process (오존공정을 이용한 고효율 PR 제거기술 연구)

  • Son, Young-Su
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.44 no.1
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    • pp.22-27
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    • 2007
  • we have been studied on the realization of the boundary layer controlled ozone process and related facilities in order to apply for the photo-resist strip process in the semiconductor and flat panel display manufacturing. By means of developing the technology for the high concentration ozone production, it was possible to realized the boundary layer control ozone process by vapor. As a result of the silicon wafer PR strip test, we obtained the strip rate of about 400nm/min at the ozone concentration of 16wt% and flow rate of 8[liter/min.].

Analysis of the Ozone Transport and Seasonal Variability in the Tropical Tropopause Layer using MERRA-2 Reanalysis Data (MERRA-2 재분석자료를 활용한 적도 대류권계면층의 오존 수송 및 계절변동성 분석)

  • Ryu, Hosun;Kim, Joowan
    • Atmosphere
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    • v.30 no.1
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    • pp.91-102
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    • 2020
  • MERRA-2 ozone and atmospheric data are utilized to test the usefulness of reanalysis-based tracer transport analysis for ozone in the tropical tropopause layer (TTL). Transport and mixing processes related to the seasonal variation of TTL ozone are examined using the tracer transport equation based on the transformed Eulerian mean, and the results are compared to previously proposed values from model analyses. The analysis shows that the seasonal variability of TTL ozone is mainly determined by two processes: vertical mean transport and horizontal eddy mixing of ozone, with different contributions in the Northern and Southern Hemispheres. The horizontal eddy mixing process explains the major portion of the seasonal cycle in the northern TTL, while the vertical mean transport dominates in the southern TTL. The Asian summer monsoon likely contributes to this observed difference. The ozone variability and related processes in MERRA-2 reanalysis show qualitatively similar features with satellite- and model-based analyses, and it provides advantages of fine-scale analyses. However, it still shows significant quantitative biases in ozone budget analysis.

Manufacturing technology of two-layer self bonding insulating tape (이중절연 자기융착테이프 제조기술)

  • 조용석;이철호;심대섭
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2001.07a
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    • pp.890-893
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    • 2001
  • Two-layer self bonding insulating tape consists of butyl rubber(IIR ; Isobutylene-isoprene rubber) adhesive layer and polyethylene protective film. Butyl rubber have inherent characteristics such as resistance to corrosion and water, low temperature flexibility, excellent electrical insulating properties also resistance to environmental effect such as ozone and ultraviolet. Polyethylene film was used for the purpose of good insulating properties and resistance to ozone and ultraviolet. The tape was manufactured using extrusion and calender method.

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Ozone Monitoring in the Lower Tropospheric Atmosphere by LIDAR System (라이다 시스템을 이용한 하층 대류권 오존농도 측정)

  • 최성철;차형기;김덕현;김영상
    • Journal of Korean Society for Atmospheric Environment
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    • v.17 no.5
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    • pp.385-393
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    • 2001
  • We have developed a Differential Absortion LIDAR (DIAL) method for the measurement of lower tropospheric ozone concentration. We used two laser beams from quadrupled Nd:YAG (266 nm) for the resonance wavelength and dye lasers (299.5 nm) for non -resonance wavelength. Aerosol extinction coefficients in the lower troposphere was computed by both Klett and Slope methods. To correct the SIN (Signal -Induced Noise) effect caused by photo detector, we subtracted a new-fitted baseline on the background part of a LIDAR signal, after the subtraction of the DC level. This is because SIN can be treated as an exponentially decaying tail. Using theme results, ozone profiles were obtained approximately 2km at daytime and 3km at nighttime. We compared the results derided by the Slope method with those measured by UV spectrometer. The computed results are in mostly good agreement with experimental results. In the measurement of the vertical layer, we observed the variation of the ozone profiles around the top mixed layer.

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Surface Ozone Episode Due to Stratosphere-Troposphere Exchange and Free Troposphere-Boundary Layer Exchange in Busan During Asian Dust Events

  • Moon, Y.S.;Kim, Y.K.;K. Strong;Kim, S.H.;Lim, Y.K.;Oh, I.B.;Song, S.K.
    • Journal of Environmental Science International
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    • v.11 no.5
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    • pp.419-436
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    • 2002
  • The current paper reports on the enhancement of O$_3$, CO, NO$_2$, and aerosols during the Asian dust event that occurred over Korea on 1 May 1999. To confirm the origin and net flux of the O$_3$, CO, NO$_2$, and aerosols, the meteorological parameters of the weather conditions were investigated using Mesoscale Meteorological Model 5(MM5) and the TOMS total ozone and aerosol index, the back trajectory was identified using the Hybrid Single-Particle Lagrangian Integrated Trajectory Model(HYSPLIT), and the ozone and ozone precursor concentrations were determined using the Urban Ashed Model(UAM). In the presence of sufficiently large concentrations of NO$\sub$x/, the oxidation of CO led to O$_3$ formation with OH, HO$_2$, NO, and NO$_2$ acting as catalysts. The sudden enhancement of O$_3$, CO, NO$_2$ and aerosols was also found to be associated with a deepening cut-off low connected with a surface cyclone and surface anticyclone located to the south of Korea during the Asian dust event. The wave pattern of the upper trough/cut-off low and total ozone level remained stationary when they came into contact with a surface cyclone during the Asian dust event. A typical example of a stratosphere-troposphere exchange(STE) of ozone was demonstrated by tropopause folding due to the jet stream. As such, the secondary maxima of ozone above 80 ppbv that occurred at night in Busan, Korea on 1 May 2001 were considered to result from vertical mixing and advection from a free troposphere-boundary layer exchange in connection with an STE in the upper troposphere. Whereas the sudden enhancement of ozone above 100 ppbv during the day was explained by the catalytic reaction of ozone precursors and transport of ozone from a slow-moving anticyclone area that included a high level of ozone and its precursors coming from China to the south of Korea. The aerosols identified in the free troposphere over Busan, Korea on 1 May 1999 originated from the Taklamakan and Gobi deserts across the Yellow River. In particular, the 1000m profile indicated that the source of the air parcels was from an anticyclone located to the south of Korea. The net flux due to the first invasion of ozone between 0000 LST and 0600 LST on 1 May 1999 agreed with the observed ground-based background concentration of ozone. From 0600 LST to 1200 LST, the net flux of the second invasion of ozone was twice as much as the day before. In this case, a change in the horizontal wind direction may have been responsible for the ozone increase.

Comparing the Passivation Quality of Ozone and H2O Oxidant of Atomic Layer Deposited Al2O3 by Post-annealing in N2 and Forming Gas Ambients for Passivated Emitter and Rear Cell (PERC)

  • Cho, Young Joon;Chang, Hyo Sik
    • Proceedings of the Korean Vacuum Society Conference
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    • 2014.02a
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    • pp.462-462
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    • 2014
  • The effect of rear passivation for passivated emitter and rear cell (PERC) using ozone and H2O oxidant of atomic layer deposited (ALD) Al2O3 was studied by post-annealing in N2 and forming gas ambients. Rear surface of PERC solar cell was passivated by Al2O3 grown by ALD with ozone and H2O oxidant. Al2O3 grown by ALD with ozone oxidant has been known to have many advantages, such as lower interface defects, low leakage current density. Its passivation quality is better than Al2O3 with H2O. Al2O3 layer with 10 nm and 20 nm thickness was grown at $150^{\circ}C$ with ozone oxidant and at $250^{\circ}C$ with H2O oxidant. And then each samples were post-annealled at $450^{\circ}C$ in N2 ambients and at $850^{\circ}C$ in forming gas ambients. The passivation quality was investigated by measuring the minority carrier lifetime respectively. We examined atomic layer deposited Al2O3 such as growth rate, film density, thickness, negative fixed charge density at AlOx/Si interface, and reflectance. The influences of process temperature and heat treatment were investigated using Sinton (WCT-120) by Quasi-Steady State Photoconductance (QSSPC) mode. Ozone-based ALD Al2O3 film shows the best carrier lifetime at lower deposition temperature than H2O-based ALD.

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A Study on Behavior of CFC and Ozone in Atmosphere (대기중 CFC 및 Ozone의 거동에 관한 연구)

  • 이내우;이진우
    • Journal of the Korean Society of Safety
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    • v.9 no.1
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    • pp.140-145
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    • 1994
  • Contributions of global warming potentials on CFC(Chlorofluorocarbon) and Ozone were calculated by Stefan-Boltzmann's law and environmental effects of its were discussed. As the greenhouse effect on the unit volume of CFC is the most strong in the infrared gases and the destruction of Ozone in stratosphere is also depends on CFC, therefore release of CFC should be prohibited. But the effect of restriction on CFC will be appeared more than 10 years later. Eventhough the Ozone layer is related to global warming, It should be protected because of maitaining food chain mode of life, preventing human disease, for example, cataract, dermatics etc.

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