• 제목/요약/키워드: Protective layer

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Influence of Silicon and Seed Particles on the Reconstruction Characteristics and Exaggerated Grain Growth of MgO Protective Layer by Over-Frequency Accelerated Discharge in ACPDPs

  • Kwon, Sang-Koo;Kim, Jeong-Ho;Moon, Seung-Kyu;Choi, Jong-Kwon;Park, Kyu-Ho;Han, Sung-Su
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2008년도 International Meeting on Information Display
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    • pp.957-960
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    • 2008
  • The influences of silicon and MgO seed particle on the reconstruction characteristics of MgO protective layer were investigated to clarify the mechanism of reconstruction and exaggerated grain growth (EGG) in AC-PDP. The reconstruction and EGG are closely correlated with the driving force for nucleation and growth, interface energy and initial size distribution of MgO protective layer in plasma space during discharge in AC-PDP.

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AC PDP에서 $SiO_2$가 첨가된 MgO 보호막의 방전 특성 연구 (A study on discharge characteristics of protective layer MgO with $SiO_2$ doped)

  • 이영권;박미영;박차수;김동현;이호준;박정후
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2003년도 하계학술대회 논문집 C
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    • pp.1683-1685
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    • 2003
  • MgO is making an important role not only as a protective layer but also improves the discharge characteristics at AC PDP. Until now, the substitute of protective layer, MgO has been studied in many ways, but it's too difficult to get a new substitute as stable as MgO. But some problems has been advanced at the discharge characteristics of MgO on high temperature. So we studied the discharge characteristics of impure MgO with $SiO_2$ doped.

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Corrosion of AI-Fe Coatings for Wet-Seal Area in Molten Carbonate Fuel Cells

  • Jun, JaeHo;Jun, JoongHwan;Kim, KyooYoung
    • Corrosion Science and Technology
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    • 제3권3호
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    • pp.98-101
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    • 2004
  • The corrosion behavior of Al-Fe coatings was studied in the wet-seal atmosphere of molten carbonate fuel cells (MCFC). Fe-8Al, Fe-16Al, Fe-25Al, Fe-36Al, and Fe-70Al (in at.%) specimens were tested in Li/K carbonate at $650^{\circ}C$ by a single cell test and an immersion test. In general, the corrosion resistance of the Al-Fe coatings was enhanced due to the formation of a protective $LiAlO_2$ layer. However, when the Al-Fe coatings didn't have sufficient content of aluminum enough for maintaining the protective layer, the corrosion resistance of the Al-Fe coatings was severely degraded by the growth of non-protective scales like $LiAlO_2$. The test results revealed that the aluminum contents in the coatings should be higher than 25 at.% in order to form and maintain the protective $LiAlO_2$ layers.

Analysis of materials for protective layers in AC PDPs.

  • Matulevich, Y. T.;Lee, Min-Suk;Kim, Suk-Ki;Choi, Jong-Seo;Zang, Dong-Sik;Kirm, Marco
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권1호
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    • pp.213-215
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    • 2007
  • To clarify processes responsible for improved characteristics of protective layers (e.g. SrCaO) the ion-induced electron emission and photoemission from these layers were analyzed. Additionally, a study of ternary Mg-, Ca-, Ba-based compounds as candidate materials for a protective layer of Plasma Display Panels has been performed as well.

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The Effect of Spacer on Microclimate and Comfort Sensation in Protective Clothing for Firefighters

  • Chung, Gi-Soo;Lee, Dae-Hoon
    • 한국의류산업학회지
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    • 제4권6호
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    • pp.564-566
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    • 2002
  • Protective clothing for firefighters typically consists of a flame resistant outer shell and inner layers. The inner layers are generally composed of a moisture barrier and a thermal barrier. On performing the task in fire place the heat and perspiration generated from the body become trapped inside the protective clothing. Those heat and moisture result into heat-stress and physical fatigue of fire fighter, which hinder the work. Therefore, the system of clothing designs and material layers must be chosen carefully to balance protection and comfort. 3 kinds of protective clothing of 3 layer structure were used in the experiment of physiological comfort. From the comparison of wear trials with the 3 kinds of layers in firefighters clothing, it indicates that the moisture dissipation of A+B2+C was highest, following A+BI+C andA+B3+C. And the heat dissipation of A+BI+C and A+B2+C were better than A+B3+C. In the protective clothing with A+B3+C, heat and perspiration generated through exercise remained in clothing system long and caused discomfort.

Effects of surface geometry of MgO protective layer for AC-PDPs

  • Park, Sun-Young;Moon, Sung-Hwan;Heo, Tae-Wook;Kim, Jae-Hyuk;Lee, Joo-Hwi;Kim, Hyeong-Joon
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권2호
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    • pp.1395-1398
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    • 2007
  • MgO thin films were deposited by e-beam evaporator using the 2-step method for alternate current plasma display panels (AC-PDPs). Glancing angle deposition (GLAD) method was employed to produce various surface geometry of the thin film; the bottom layer was deposited on a substrate by normal e-beam evaporation method and the top layer was deposited on bottom layer with $85^{\circ}$ by GLAD method. Results show that firing and sustain voltages improved as the sharpness of surface and isolated columnar structures increases, respectively.

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High Luminous Efficacy and Low Driving Voltage PDP with SrO-MgO Double Protective Layer

  • Whang, Ki-Woong;Jung, Hae-Yoon;Lee, Tae-Ho;Cheong, Hee-Woon
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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    • pp.173-176
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    • 2009
  • We suggest a new protective layer for PDP consists of SrO and MgO double layer. This double layer structure protects SrO layer from the contamination by $H_2O$ or $CO_2$ in the air and enable SrO to play as the main cathode material. It was confirmed that the high secondary electron emission characteristics of SrO by Xe ion can bring considerable driving voltage reduction and improvement of luminance and luminous efficacy in PDP.

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소재에 따른 자외선.복사열 차단력 (Protection Efficiency from Solar Radiation and Ultraviolet Radiation by Fabrics)

  • 김경수;최정화
    • 대한가정학회지
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    • 제40권10호
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    • pp.77-85
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    • 2002
  • This study was conducted to evaluate the efficiency of various fabrics in protecting from solar radiation and ultraviolet radiation(UV). Six kinds of fabrics were selected and examined in singles or doubles. It was studied how the materials and the thickness of air layer between the fabric and the floor affected the protection efficiency of fabrics from sunlight. The results were as followes; 1) Protection from solar radiation: In the case of over 2 cm air layer, doubled fabric composed of aluminum coating-nylon and white or black polyester/cotton(T/C) was the most protective(p<0.001). In the case of 0 cm air layer, the case without fabric and white T/C were more effective(p<0.001). And the thicker the air layer the more effective the protection. 2) Protection from UV : Doubled fabric composed of aluminum coating-nylon and black T/C was the most protective(p<0.001) and the thinner the air layer the more effective the protection(p<0.001).

Investigation of Sweet and Sour Corrosion of Mild Steel in Oilfield Environment by Polarization, Impedance, XRD and SEM Studies

  • Paul, Subir;Kundu, Bikramjit
    • Corrosion Science and Technology
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    • 제17권5호
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    • pp.249-256
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    • 2018
  • Metallic structures in the oil and gas production undergo severe degradation due to sweet and sour corrosion caused by the presence of $CO_2$ and $H_2S$ in the fluid environment. The corrosion behavior of 304 austenitic stainless was investigated in the presence of varying concentrations of $CO_2$ or $H_2S$ and $CO_2+H_2S$ to understand the effect of the parameters either individually or in combination. Potentiodynamic polarization study revealed that a small amount of $CO_2$ aided in the formation of calcareous deposit of protective layer on passive film of 304 steel, while increase in $CO_2$ concentration ruptured the layer resulting in sweet corrosion. The presence of $S^{2-}$ damaged the passive and protective layer of the steel and higher levels increased the degradation rate. Electrochemical impedance studies revealed lower polarization resistance and impedance at higher concentration of $CO_2$ or $H_2S$, supporting the outcomes of polarization study. XRD analysis revealed different types of iron carbides and iron sulphides corresponding to sweet and sour corrosion as the corrosion products, respectively. SEM analysis revealed the presence of uniform, localized and sulphide cracking in sour corrosion and general corrosion with protective carbide layer amid for sweet corrosion.

Terabit-per-square-inch Phase-change Recording on Ge-Sb-Te Media with Protective Overcoatings

  • Shin Jin-Koog;Lee Churl Seung;Suh Moon-Suk;Lee Kyoung-Il
    • 정보저장시스템학회:학술대회논문집
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    • 정보저장시스템학회 2005년도 추계학술대회 논문집
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    • pp.185-189
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    • 2005
  • We reported here nano-scale electrical phase-change recording in amorphous $Ge_2Sb_2Te_5$ media using an atomic force microscope (AFM) having conducting probes. In recording process, a pulse voltage is applied to the conductive probe that touches the media surface to change locally the electrical resistivity of a film. However, in contact operation, tip/media wear and contamination could major obstacles, which degraded SNR, reproducibility, and lifetime. In order to overcome tip/media wear and contamination in contact mode operation, we adopted the W incorporated diamond-like carbon (W-DLC) films as a protective layer. Optimized mutilayer media were prepared by a hybrid deposition system of PECVD and RF magnetron sputtering. When suitable electrical pulses were applied to media through the conducting probe, it was observed that data bits as small as 25 nm in diameter have been written and read with good reproducibility, which corresponds to a data density of $1 Tbit/inch^2$. We concluded that stable electrical phase-change recording was possible mainly due to W-DLC layer, which played a role not only capping layer but also resistive layer.

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