• 제목/요약/키워드: carbon effect

검색결과 5,661건 처리시간 0.036초

Effect of ultra - violet laser treatment on multi - wall carbon nanotube surface

  • Kim, Jun-Sik;Ahn, Kyoung-Soo;Lee, Chang-Hyo;Kim, Chae-Ok;Hong, Jin-Pyo
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2002년도 International Meeting on Information Display
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    • pp.689-691
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    • 2002
  • Well-aligned multi-wall carbon nanotubes (MWCNTs) have been grown on both Coming glass and silicon substrates at about 400 $^{\circ}C$ by a modified plasma - enhanced chemical vapor deposition system. We have investigated laser irradiation effect on carbon nanotube surface by using an ultra - violet laser. The laser operated to modify structural defect of was carbon nanotube and to ablate possible contamination of carbon nanotube surface. The morphology and surface transformation of MWCNTs as analyzed by a SEM. In addition, the field emission measurement was also carried out in a vacuum chamber with a $10^{-7}$ Torr base pressure by applying bias voltages up to 1000V.

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사염화탄소(四鹽化炭素) 간장장해(肝臟障害) 동물(動物)에서의 Sulfisoxazole의 흡수(吸收)와 배설(排泄)에 관(關)한 연구(硏究) (The Effects of Pretreatment with Carbon Tetrachloride on the Absorption and Excretion of Sulfisoxazole)

  • 최준식
    • Journal of Pharmaceutical Investigation
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    • 제6권2호
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    • pp.88-94
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    • 1976
  • This paper attempted to investigate the effect of pretreatment with carbon tetrachloride on absorption, excretion, protein binding, and biological half-life of sulfisoxazol from rats and rabbits. Absorption of sulfisoxazol was found to decrease in severe damage rats, compared with that of normal rats, but in mild rats, absorption of sulfisoxazol was similar to that of nomal rats. Absorption of sulfisoxazol was decreased significantly in severe damage rabbit pretreated with carbon tetrachloride but in mild damage rabbit, absorption of sulfisoxazol was not influenced significantly. Pretreatment with carbon tetrachloride gave the effect on clearance of sulfisoxazol in part but protein binding percent of sulfisoxazol was not influenced by concentration of carbon tetrachloride.

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A Study of the Gas Liquid Partition Coefficients of Eleven Normal, Branched and Cyclic Alkanes in Sixty Nine Common Organic Liquids: The Effect of Solute Structure

  • Cheong, Won-Jo
    • Bulletin of the Korean Chemical Society
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    • 제23권3호
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    • pp.459-468
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    • 2002
  • Literature data measured by the author have been processed to report on the effect of solute structure on gas liquid partition coefficients of eleven normal, branched and cyclic alkanes ranging in carbon number from five to nine in sixty nine low molecular weight liquids. The alkane solutes are n-pentane(p), n-hexane(hx), n-heptane(hp), n-octane(o), n-nonane(n), 2-methylpentane(mp), 2,5-dimethylpentane(dp), 2,5-dimethylhexane(dh), 2,3,4-trimethylpentane(tp), cyclohexane(ch), and ethylcyclohexane(ec). The solvent set encompasses most of those studied by Rohrschneider as well as three homologous series of solvents (n-alkanes, 1-alcohols and 1-nitriles) and several perfluorinated alkanes and highly fluorinated alcohols. An excellent linear relationship was observed between lnK and the carbon number of n-alkanes. The effective carbon numbers of branched and cyclic alkanes were determined in a similar fashion to the method of Kovats index. We found that the logarithm of solute vapor pressure multiplied by solute molar volume was a perfect descriptor for the linear relationship with the median effective carbon number.

미연분 및 NOx배출 특성에 대한 고회분탄의 영향 연구 (Effect of High Ash Coal on Unburned Carbon and NOx Emission)

  • 김상인;이병화;임호;안기주;김만철;송주헌;전충환
    • 한국연소학회:학술대회논문집
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    • 한국연소학회 2012년도 제44회 KOSCO SYMPOSIUM 초록집
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    • pp.341-342
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    • 2012
  • The effect of high ash coal which has relatively high ash content and low combustibility on unburned carbon and NOx emission was experimentally investigated at several excess air ratio and particle size conditions of four coals containing different ash content in a drop tube furnace. Flue gas was measured by Gas analyzer in order to figure out unburned carbon characteristics. The results show that the higher content of ash makes the higher unburned carbon rate, subsequent changes in NOx emission characteristics was investigated.

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탄소섬유시트로 보강된 춤이 큰 철근콘크리트 보의 전단파괴거동(剪斷破壞擧動) (Shear Failure Behaviour of Reinforced Concrete Deep Beam Strengthened by Carbon Fiber Sheets)

  • 조수제;손성현;박성수
    • 한국구조물진단유지관리공학회 논문집
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    • 제3권4호
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    • pp.145-153
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    • 1999
  • The major objective of this study is to investigate experimentally the shear strengthening effect of carbon fiber sheets upon reinforced concrete deep beam and shear failure behavior variation of reinforced concrete deep beam strengthened by carbon fiber sheets. Tests are carried out with 6 specimens were shear failure at first loading tests, and with parameters including the types of shear strengthening of carbon fiber sheets (I type, S type, U type), and plies of sheets (2 ply and 1 ply). From the results of test, analyzed load-deflection of midspan, strain variation of main bars and transverse reinforcement, maximum load capacity of strengthened specimens, and compared with the previous test results.

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아공정 구상흑연주철의 Fading 거동에 미치는 탄소당량의 영향 (Effect of Carbon Equivalent on the Fading Behavior of Hypoeutectic Ductile Cast Iron)

  • 박헌범;박상준
    • 한국주조공학회지
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    • 제24권5호
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    • pp.290-294
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    • 2004
  • The effect of carbon equivalent on the fading behavior of hypoeutectic ductile cast iron was investigated. The carbon content was slightly increased right after graphite spheroidization treatment and remained almost constant with holding at $1,490^{\circ}C$ after 4 minute. The residual magnesium content was decreased slowly with holding. The empirical equation expressing the relationship between this and holding time was proposed ; $C=C_o-P{\times}t$. The proportionality constant, P, was inversely proportional to carbon content.

The effect of pore structure and surface properties of carbon nanotube films on the performance of a lithium sulfur battery

  • Song, Hyeonjun;Hwang, Yunjae;Kumar, Vimal Tiwari;Jeong, Youngjin
    • Carbon letters
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    • 제27권
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    • pp.12-17
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    • 2018
  • We fabricated a Li-S battery with post-treated carbon nanotube (CNT) films which offered better support for sulfur, and investigated the effect of the surface properties and pore structure of the post-treated CNT films on Li-S battery performance. Post-treatments, i.e., acid treatment, unzip process and cetyltrimethylammonium bromide (CTAB) treatment, effectively modified the surface properties and pore structure of the CNT film. The modified pore structure impacted the ability of the CNT films to accommodate the catholyte, resulting in an increase in initial discharge capacity.

Effect of Carbon Addition and Sintering Temperature on Densification and Microstructural Evolution of Sinter-Hardening Alloys Steels

  • Verma, N.;Anand, S.;Upadhyaya, A.
    • 한국분말야금학회:학술대회논문집
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    • 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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    • pp.557-558
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    • 2006
  • In all conventional sintered PM products, the pores present are of two types, primary and secondary. Primary pores forming during compaction and latter during sintering, due to penetration of formed liquid through the matrix grain boundary. Effect of carbon addition on diffusion of Cu in SH737-2Cu system was investigated. After compaction and transient liquid phase sintering at $1120^{\circ}C$ and $1180^{\circ}C$, samples were characterized for densification, showing rise in sintering density and reduction in swelling on carbon addition. Quantitative microstructural characterization (shape factor and pore size) revealed bimodal distribution for 0% carbon, more rounded pores for 0.9% carbon and higher sintering temperature, and pore coarsening at higher sintering temperature.

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저탄소강의 고출력 $CO_2$ 레이저 빔 용접 (High power $CO_2$ laser beam welding for low carbon steels)

  • 김재도
    • Journal of Welding and Joining
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    • 제7권4호
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    • pp.12-21
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    • 1989
  • Laser beam welding parameters have experimentally investigated, using a continuous wave 3kW $CO_2$ laser with the various travel speeds, beam mode and laser beam power in low carbon steels. An optimum position of focus and the effect of shielding gas on penetration depth with varying the flow range of 0.5 to 5.1m/min have been combined to investigate the effect of laser power and travel speed on penetration depth and bead width. It is found that the optimum position of focus in 3kW class laser is 0.5 to 1.5mm below the surface of the material. The flow rate of shielding gas affects the penetration depth and He is more effective than Ar. The penetration depth in laser welds of low carbon steels is between two and four times of the bead width. Laser beam welding of butt joints in 2mm thick carbon steel has been carried out to establish a weldability lobe. The lobe indicating acceptable welding conditions is introduced.

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탄소분말이 함유된 마이크로 그리드패턴 전기용량형 압력센서 (Carbon Black Containing Micro-Grid Patterned Piezocapacitive Pressure Sensor)

  • 마성용;장승환
    • Composites Research
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    • 제32권5호
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    • pp.237-242
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    • 2019
  • 이 연구에서는 마이크로 그리드 패턴 표면을 갖는 탄소 분말이 첨가된 Poly-dimethylsiloxane (PDMS)를 사용하여 전기용량형 압력센서(Piezocapacitive Sensor)를 제작하였다. 탄소 분말과 그리드 패턴이 센서의 성능에 미치는 효과를 알아보기 위해 탄소 분말의 농도와 그리드 패턴의 밀도를 달리하여 여러 개의 센서를 제작하였다. 센서의 작동 범위와 민감도를 척도로 센서의 성능을 비교하였다.