• Title/Summary/Keyword: ozone layer

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Study on the deposition Characteristics of Bi Thin Film (Bi 박막의 성막 특성에 관한 연구)

  • Yang, Dong-Bok;Park, Yong-Pil;Lee, Hee-Kab
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2003.05d
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    • pp.61-64
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    • 2003
  • This paper presents Bi thin films have been fabricated by atomic layer-by-layer deposition and co-deposition at an IBS method. The growth rates of the films was set in the region from 0.17 to 0.27 nm/min. Mg(100) was used as a substrate. In order to appreciate stable existing region of Bi 2212 phase with temperature and ozone pressure, the substrate temperature was varied between 655 and $820^{\circ}C$ and the highly condensed ozone gas pressure$(PO_3)$ in vacuum chamber was varied between $2.0{\times}10^{-6}$ and $2.3{\times}10^{-5}$ Torr. Bi 2212 phase appeared in the temperature range of 750 and $795^{\circ}C$ and single phase of Bi 2201 existed in the lower region than $785^{\circ}C$. Whereas, $O_3$ dependance on structural formation was scarcely observed regardless of the pressure variation. And high quality of c-axis oriented Bi 2212 thin film with $T_c$(onset) of about 90 K and $T_c$(zero) of about 45 K is obtained. Only a small amount of CuO in some films was observed as impurity, and no impurity phase such as $CaCuO_2$ was observed in all of the obtained films.

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Study on the deposition Characteristics of Bi Thin Film (Bi 박막의 성막 특성에 관한 연구)

  • 최철호;임중관;박용필;이화갑
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2003.05a
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    • pp.615-618
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    • 2003
  • This paper presents Bi thin films have been fabricated by atomic layer-by-layer deposition and co-deposition at an IBS method. The growth rates of the films was set in the region from 0.17 to 0.27 nm/min. MgO(l00) was used as a substrate. In order to appreciate stable existing region of Bi 2212 phase with temperature and ozone pressure, the substrate temperature was varied between 655 and 820 $^{\circ}C$ and the highly condensed ozone gas pressure(PO$_3$) in vacuum chamber was varied between 2.0$\times$10$^{-6}$ and 2.3$\times$10$^{-5}$ Torr. Bi 2212 phase appeared in the temperature range of 750 and 795$^{\circ}C$ and single phase of Bi 2201 existed in the lower region than 785 $^{\circ}C$. Whereas, PO$_3$ dependance on structural formation was scarcely observed regardless of the pressure variation. And high quality of c-axis oriented Bi 2212 thin film with T$_{c}$(onset) of about 90 K and T$_{c}$(zero) of about 45 K is obtained. Only a small amount of CuO in some films was observed as impurity, and no impurity phase such as CaCuO$_2$ was observed in all of the obtained films.lms.

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NiOx-based hole injection layer for organic light-emitting diodes (유기발광소자에 적용 가능한 NiOx 기반의 정공주입층 연구)

  • Kim, Junmo;Gim, Yejin;Lee, Wonho;Lee, Donggu
    • Journal of Sensor Science and Technology
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    • v.30 no.5
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    • pp.309-313
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    • 2021
  • Organic semiconductors have received tremendous attention for their research because of their tunable electrical and optical properties that can be achieved by changing their molecular structure. However, organic materials are inherently unstable in the presence of oxygen and moisture. Therefore, it is necessary to develop moisture and air stable semiconducting materials that can replace conventional organic semiconductors. In this study, we developed a NiOx thin film through a solution process. The electrical characteristics of the NiOx thin film, depending on the thermal annealing temperature and UV-ozone treatment, were determined by applying them to the hole injection layer of an organic light-emitting diode. A high annealing temperature of 500 ℃ and UV-ozone treatment enhanced the conductivity of the NiOx thin films. The optimized NiOx exhibited beneficial hole injection properties comparable those of 1,4,5,8,9,11-hexaazatriphenylene hexacarbonitrile (HAT-CN), a conventional organic hole injection layer. As a result, both devices exhibited similar power efficiencies and the comparable electroluminescent spectra. We believe that NiOx could be a potential solution which can provide robustness to conventional organic semiconductors.

Investigation of SO2 Effect on TOMS O3 Retrieval from OMI Measurement in China (OMI 위성센서를 이용한 중국 지역에서 TOMS 오존 산출에 대한 이산화황의 영향 조사 연구)

  • Choi, Wonei;Hong, Hyunkee;Kim, Daewon;Ryu, Jae-Yong;Lee, Hanlim
    • Korean Journal of Remote Sensing
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    • v.32 no.6
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    • pp.629-637
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    • 2016
  • In this present study, we identified the $SO_2$ effect on $O_3$ retrieval from the Ozone Monitoring Instrument (OMI) measurement over Chinese Industrial region from 2005 through 2007. The Planetary boundary layer (PBL) $SO_2$ data measured by OMI sensor is used in this present study. OMI-Total Ozone Mapping Spectrometer (TOMS) total $O_3$ is compared with OMI-Differential Optical Absorption Spectrometer (DOAS) total $O_3$ in various $SO_2$ condition in PBL. The difference between OMI-TOMS and OMI-DOAS total $O_3$ (T-D) shows dependency on $SO_2$ (R (Correlation coefficient) = 0.36). Since aerosol has been reported to cause uncertainty of both OMI-TOMS and OMI-DOAS total $O_3$ retrieval, the aerosol effect on relationship between PBL $SO_2$ and T-D is investigated with changing Aerosol Optical Depth (AOD). There is negligible aerosol effect on the relationship showing similar slope ($1.83{\leq}slope{\leq}2.36$) between PBL $SO_2$ and T-D in various AOD conditions. We also found that the rate of change in T-D per 1.0 DU change in PBL, middle troposphere (TRM), and upper troposphere and stratosphere (STL) are 1.6 DU, 3.9 DU and 4.9 DU, respectively. It shows that the altitude where $SO_2$ exist can affect the value of T-D, which could be due to reduced absolute radiance sensitivity in the boundary layer at 317.5 nm which is used to retrieve OMI-TOMS ozone in boundary layer.

A Study on the Performance Improvement for Flexible PCDTBT : PC71BM Organic Thin Film Solar Cell by Ozone Surface Treatment of ITO Electrode (ITO 전극의 오존 표면처리에 의한 플렉시블 PCDTBT : PC71BM 유기박막 태양전지의 성능 개선에 관한 연구)

  • No, Im-Jun;Lim, Young-Taek;Shin, Paik-Kyun
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.26 no.11
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    • pp.104-108
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    • 2012
  • Flexible organic thin film solar cell device with Bulk Hetero-Junction (BHJ) structure was fabricated with blended conjugated polymer of PCDTBT : $PC_{71}BM$ as active layer. Surface of ITO anode for the organic solar cell device was treated with ozone. The organic solar cell device with bare ITO showed short circuit current density ($J_{sc}$) of $8.2mA/cm^2$, open-circuit voltage ($V_{oc}$) of 0.73V, fill factor (FF) of 0.36, and power conversion efficiency (PCE) of 2.16%, respectively. The organic solar cell device with ozone treated ITO anode revealed distinctively improved performance parameters:$J_{sc}$ of $9.8mA/cm^2$, $V_{oc}$ of 0.82V, FF of 0.43, PCE(${\eta}$) of 3.42%.

A Review on the Photochemical Oxidant Modeling as Applied to Air Quality Studies in Complex Terrain

  • Hwa-Woon Lee;Yoo
    • Journal of Environmental Science International
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    • v.1 no.1
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    • pp.19-33
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    • 1992
  • The high oxidants, which occur the daily maximum concentrations in the afternoon, are transported into the other region via long range transport mechanisms or trapped within the shallow mixing boundary layer and then removed physically (deposition, transport by mountain wind, etc.) and chemically (reaction with local sources). Therefore, modeling formation of photochemical oxidants requires a complex description of both chemical and meteorolog ital processecs . In this study, as a part of air quality studies, we reviewed various aspects of photochemical modeling on the basis of currently available literature. The result of the review shows that the model is based on a set of coupled continuity equations describing advection, diffusion, transport, deposition, chemistry, emission. Also photochemical oxidant models require a large amount of input data concerned with all aspects of the ozone life cycle. First, emission inventories of hydrocarbon and nitrogen oxides, with appropriate spatial and temporal resolution. Second, chemical and photochemical data allowing the quantitative description of the formation of ozone and other photochemically-generated secondary pollutants. Third, dry deposition mechanisms particularly for ozone, PAN and hydrogen peroxide to account for their removal by absorption on the ground, crops, natural vegetation, man-made and water surfaces. Finally, meteorological data describing the transport of primary pollutants away from their sources and of secondary pollutants towards the sensitive receptors where environmental damage may occur. In order to improve our present study, shortcomings and limitation of existing models are pointed out and verification Process through observation is emphasized.

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Thick Film Type duster in Mg2SiO4/Glass composite ceramics for Anion Generation (Mg2SiO4/Glass Composite계 세라믹스를 이용한 음이온 발생용 후막형 클러스터)

  • Yeo, Dong-Hun;Shin, Hyo-Soon;Hong, Youn-Woo
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.23 no.2
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    • pp.118-123
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    • 2010
  • The eco-friendly technologies have been extended as matter of international concern due to various diseases and syndromes according to an environmental pollution. In this study, we have manufactured a ceramic cluster with thick film type for anion generation equipment which is maximized anion but minimized ozone contents generated. To develop the formulation of ceramic cluster, we conducted the $Mg_2SiO_4$ powders doped with 10 vol% glass frits as Na-Zn-B-O system and sintered at $1050^{\circ}C$ for 2 hours in air for starting materials and investigated the matching properties between the Ag-Pd electrode and the starting materials. The sintered sample for the composition of cluster has 6.7 of dielectric constant and 32 kV/mm of withstand voltage. The yield of anions was measured according to an electrode pattering, discharge gap between electrode, and thickness of electrode protective layer in the cluster of thick film type. We have manufactured the ceramic clusters with optimized thick film structure that have an anion over a hundred particles and the ozone of 0.6 ppb generated.

Numerical Study on the Ozone Formation Sensitivity of Precursors Using Adjoint Model around the South-eastern Area of the Korean Peninsula (수반모형을 이용한 한반도 남동지역의 오존 전구물질의 오존 생성 민감도에 관한 수치연구)

  • Park, Soon-Young;Lee, Soon-Hwan;Lee, Hwa Woon;Kim, Dong-Hyeok
    • Journal of the Korean earth science society
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    • v.34 no.7
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    • pp.669-680
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    • 2013
  • Ozone sensitivity analysis with respect to $NO_x$ is conducted around the south-eastern area of the Korean Peninsula. WRF-CMAQ modeling system is used to simulate a local circulation and high ozone episode day. To analyze the sensitivity, the adjoint model for CMAQ is adopted in this study. The purpose of current study is to investigate the location that affects a day time ozone concentration of these receptors on the high ozone episode day. Adjoint sensitivity analysis for Daegu shows two areas of influence. One is the range from the neighboring location to Pohang and it affects mainly on the same day as receptor time. The other is the remote south-eastern area from Daegu. This remote influence area suggests that $NO_x$ emitted on the previous day can change the ozone concentration at receptor time. The influence area for Busan, on the other hand, is originated only from the emission on the previous day because the sea-breeze occurred on the episode day makes low influence of surrounding emission. The cross sectional analysis reveals that $NO_x$ advection is important not only near the surface of land but also around the height of boundary layer.

A Design of Telemetry Ground System for the Scientific Sounding Rocket KSR-420S (과학관측로케트 KSR-420S의 원격측정 지상시스템 설계)

  • 이수진;이재득;조광래;유장수
    • The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
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    • v.2 no.4
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    • pp.26-32
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    • 1991
  • Korea Aerospace Research Institute(KARI) performs research on developing the scientific sounding rocket(KSR-420S) for measuring ozone profile and atmosphere layer over korean peninsula. Informations about performances of flighting scientific rocket, that is temperature, strain, acceleration, pressure, rocket attitude and ranging data, and measuring data of ozone, ionosphere and X-ray are transmitted ground system by rocket onboard transmitting system. In this paper, the telemetry ground system which is compatible with the KSR-420S is designed for tracking the trajectory and receiving the incoming signals.

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Studies on Ozonation of Nicotine (니코틴의 오존화 반응에 관한 연구)

  • Taek-Kyu Park;Ki-Hwan Kim;Tae-Sung Huk
    • Journal of the Korean Chemical Society
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    • v.28 no.5
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    • pp.323-327
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    • 1984
  • Nicotine was reacted with an equimolar amount of ozone in methylene chloride and distilled water. The reaction mixture was separated by column chromatography or thin layer chromatography and then purified by vacuum distillation. The six compounds obtained from this reaction were characterized by NMR, IR and Mass spectrometry. These were identified as unchanged nicotine, nornicotine, anabasine, ${\beta}$-nicotyrine, cotinine and nicotine-N-oxide. From these results, reaction mechanism for the ozonolysis ofon nicotine was proposed; the pyrrolidine ring is attacked by ozone at the 1'-position followed by further transformation.

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