• 제목/요약/키워드: Surface Characterization

검색결과 2,085건 처리시간 0.031초

아미드 작용기를 가진 부식억제제를 사용한 금속의 전기화학적 특성 (Electrochemistry Characterization of Metal Using Corrosion Inhibitors Containing Amide Functional Group)

  • 박근호
    • 한국응용과학기술학회지
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    • 제28권1호
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    • pp.48-56
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    • 2011
  • In this study, we investigated the C-V diagrams and metal surface related to the electrochemistry characterization of metal(nickel, SUS-304). We determined electrochemical measurement by using cyclic voltammetry with a three-electrode system. A measuring range was reduced from initial potential to -1350mV, continuously oxidized to 1650 mV and measured to the initial point. The scan rate were 50, 100, 150, 200 and 250 mV/s. As a result, the C-V characterization of metal using N,N-dimethylacetamide and N,N-dimethylformamide inhibitors appeared irreversible process caused by the oxidation current from the cyclic voltammogram. After adding organic corrosion inhibitors, adsorption film constituted, and the passive phenomena happened. According to the results by cyclic voltammetry method, it was revealed that the addition of inhibitors containing amide functional group enhances the corrosion resistance properties.

Thermal Characterization of Individual Pixels in Microbolometer Image Sensors by Thermoreflectance Microscopy

  • Ryu, Seon Young;Choi, Hae Young;Kim, Dong Uk;Kim, Geon Hee;Kim, Taehyun;Kim, Hee Yeoun;Chang, Ki Soo
    • JSTS:Journal of Semiconductor Technology and Science
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    • 제15권5호
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    • pp.533-538
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    • 2015
  • Thermal characterization of individual pixels in microbolometer infrared image sensors is needed for optimal design and improved performance. In this work, we used thermoreflectance microscopy on uncooled microbolometer image sensors to investigate the thermal characteristics of individual pixels. Two types of microbolometer image sensors with a shared-anchor structure were fabricated and thermally characterized at various biases and vacuum levels by measuring the temperature distribution on the surface of the microbolometers. The results show that thermoreflectance microscopy can be a useful thermal characterization tool for microbolometer image sensors.

수열 압력 제조 조건이 MoS2 촉매 특성과 직접 메탄화 반응에 미치는 영향 (Hydrothermal Pressure Effect over Preparation of MoS2: Catalyst Characterization and Direct Methanation)

  • 박정환;김성수;김진걸
    • 한국수소및신에너지학회논문집
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    • 제29권2호
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    • pp.170-180
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    • 2018
  • After $MoS_2$ catalyst was prepared at 1, 30, and 70 atm, the hydrothermal pressure effect over preparation of $MoS_2$ was investigated in terms of catalyst characterization and direct methanation. Multifaceted characterization techniques such as XRD, BET, SEM, TPR, EDS, and XPS were used to analyze and investigate the effect of high pressure over the preparation of surface and bulk $MoS_2$ catalyst. Result from XRD, SEM, and BET demonstrated that $MoS_2$ was more dispersed as preparation pressure was increased, which resulted finer $MoS_2$ crystal size and higher surface area. EDS result confirmed that bulk composition was $MoS_2$ and XPS result showed that S/Mo mole ratio of surface was about 1.3. TPR showed that $MoS_2$ prepared at 30 atm possessed higher active surface sites than $MoS_2$ prepared at 1 atm and these sites could contribute to higher CO yield during methanation. Direct methanation was used to evaluate the CO conversion of the both catalysts prepared at 1 atm and 30 atm and reaction condition was at feed mole ratio of $H_2/CO=1$, GHSV=4800, 30 atm, temperature($^{\circ}C$) of 300, 350, 400, and 450. $MoS_2$ prepared at 30 atm showed more stable and higher CO conversion than $MoS_2$ prepared at 1 atm. Faster deactivation was occurred over $MoS_2$ prepared at 1 atm, which indicated that preparation pressure of $MoS_2$ catalyst was the dominant factor to improve the yield of direct methanation.