• Title/Summary/Keyword: Annealed

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Catalytic NiO Filter Supported on Carbon Fiber for Oxidation of Volatile Organic Compounds

  • Sim, Jong Ki;Seo, Hyun Ook;Jeong, Myung-Geun;Kim, Kwang-Dae;Kim, Young Dok;Lim, Dong Chan
    • Bulletin of the Korean Chemical Society
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    • v.34 no.7
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    • pp.2105-2110
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    • 2013
  • Carbon-fiber-supported NiO catalytic filters for oxidation of volatile organic compounds were prepared by electroless Ni-P plating and subsequent annealing processes. Surface structure and crystallinity of NiO film on carbon fiber could be modified by post-annealing at different temperatures (500 and $650^{\circ}C$). Catalytic thermal decompositions of toluene over these catalytic filters were investigated. $500^{\circ}C$-annealed sample showed a higher catalytic reactivity toward toluene decomposition than $650^{\circ}C$-annealed one under same conditions, despite of its lower surface area and toluene adsorption capacity. X-ray diffraction and X-ray photoelectron spectroscopy studies suggest that amorphous structures of NiO on $500^{\circ}C$-annealed catalyst caused the higher reactivity for oxidation of toluene than that of $650^{\circ}C$-annealed sample with a higher crystallinity.

Influence of Post Deposition Electro-Annealing on the Properties of ITO Thin Film Deposited on a Polymer Substrate

  • Kim, Dae-Il
    • Korean Journal of Materials Research
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    • v.19 no.9
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    • pp.499-503
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    • 2009
  • Transparent ITO films were deposited on a polycarbonate substrate with RF magnetron sputtering in a pure argon (Ar) and oxygen ($O_2$) gas atmosphere, and then post deposition electro annealed for 20 minutes in a $4{\times}10^{-1}$ Pa vacuum. Electron bombardment with an accelerating voltage of 100 V increased the substrate temperature to $120^{\circ}C$. XRD analysis of the deposited ITO films did not show any diffraction peaks, while electro annealed films indicated the growth of crystallites on the (211), (222), and (400) planes. The sheet resistance of ITO films decreased from 103 to $82{\Omega}/\square$. The optical transmittance of ITO films in the visible wavelength region increased from 85 to 87%. Observation of the work function demonstrated that the electro-annealing increased the work function of ITO films from 4.4 to 4.6 eV. The electro annealed films demonstrated a larger figure of merit of $3.0{\times}10^{-3}{\Omega}^{-1}$ than that of as deposited films. Therefore, the electro annealed films had better optoelectrical performances than as deposited ITO films.

A Study on Growth Characteristics of the Surface Fatigue Crack Propagated from a Small Surface Defect in Carbon Steels (탄소강재(炭素鋼材)의 작은 표면결함(表面缺陷)에서 성장(成長)하는 표면피로(表面疲勞)균열의 성장특성(成長特性)에 관한 연구(硏究))

  • Chang-Min,Suh;Yong-Goo,Kang
    • Bulletin of the Society of Naval Architects of Korea
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    • v.21 no.1
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    • pp.35-42
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    • 1984
  • In the present study, rotating bending fatigue tests have been carried out in three kinds of carbon steel specimens; an annealed low carbon steel, an annealed high carbon steel and quenched-tempered high carbon steel; with a small artificial surface defect that might exist in real structures. Fatigue crack lengths have been observed by a method of replication in order to investigate the growth characteristic of fatigue crack in the viewpoints of strength of materials and fracture mechanics. The main results obtained are as follows: 1) The effect of a small surface defect upon the reduction of fatigue limit is considerably large, and the rate of fatigue limit reduction grows in the following order; annealed low carbon steel(mild steel), annealed high carbon steel, quenched-tempered high carbon steel. 2) When the growth rate of surface crack length(2a) was investigated in the viewpoints of fracture mechanics based upon $ ${\Delta}K_{\varepsilon}$, the dependence of stress level and of surface defect size disappear, and there exists a linear relationships between d(2a)/dN and ${\Delta}K_{{\varepsilon}t},\;\Delta_{{\varepsilon}t}\sqrt{{\pi}a}$, on log. plot, i.e, $d(2a)/dN={C{\cdot}{\Delta}K_{\varepsilon}}^3_t$, where ${\Delta}_{{\varepsilon}t}\sqrt{{\pi}a}$ a is the cyclic total strain intensity factor range.

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A Study on the Turning of SCM440 Hardened Steel (SCM440 경화 처리강의 선삭저항에 관한 연구)

  • 정기영
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.8 no.5
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    • pp.102-107
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    • 1999
  • In this paper hardened SCM440 material and annealed SCM440 material are for cutting experiments by the cutting con-dition which is chosen respectively by tool three components of cutting force are recorded using multicorder, Then the surface roughness for various force are measured by Roughness Tester. The results of the experiment are summarized as follow. The hardened material cut by ceramic tool(BX20) gives the highest radial component values among the cutting resistance radial components is increased higher for the higher cutting speed even though vertical component and axial component tend to decrease. But when the annealed material was cut increase in cutting speed results in the increase of three component forces. Since ceramic insert tip used the experiment hardly affect Built-up Edge and heat the cutting resistance decrease slightly regardless of the increased of cutting speed. The hardened material has higher three compo-nent force value than the annealed material because the material of high hardness is increased cutting resistance. The low-est cutting forces for hardened material and annealed material are shown in the cutting speed of 60m/min and 180m/min. respectively.

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The Changes of the Microstructure and the Physical Properties of Heat Set PET Partially Oriented Yarns (PET부분배향사(POY)의 열처리에 따른 내부구조 및 물성변화)

  • Choi Jong Myoung;Cho Gil Soo
    • Journal of the Korean Society of Clothing and Textiles
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    • v.12 no.3 s.28
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    • pp.343-350
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    • 1988
  • This study was carried out to investigate the microstructure and physical property of PET POY which was taut-annealed under various conditions. The DSC melting curves of annealed PET POY showed double melting peaks in most cases. As temperature and time increased, form II crystal became sharp and increased in size, and form I crystal decreased in size. The slower the heating rate, the higher the programmed heating effect during DSC analysis. Crystallinity and briefringence of annealed specimens increased as the treatment temperature and time increased. Breaking tenacity of specimens treated for 3 minutes increased as the treatment temperature increased, but others decreased. Elongation at break decreased as the annealing temperature and time increased. Dye uptake of annealed specimens decreased as the temperature increased up to $190^{\circ}C\~210^{\circ}C$. then the uptakes increased at higher temperatures. At the same temperature, dye uptake of the specimen decreased as time increased.

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Effect of annealing pressure on the growth and electrical properties of $YMnO_3$ thin films deposited by MOCVD

  • Shin, Woong-Chul;Park, Kyu-Jeong;Yoon, Soon-Gil
    • Journal of Korean Vacuum Science & Technology
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    • v.4 no.1
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    • pp.6-10
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    • 2000
  • Ferroelectric YMnO$_3$ thin films were deposited on $Y_2$O$_3$/si(100) substrates by metalorganic chemical vapor deposition. The YMnO$_3$ thin films annealed in vacuum ambient (100 mTorr) above 75$0^{\circ}C$ show hexagonal structured YMnO$_3$. However, the film annealed in oxygen ambient shows poor crystallinity, and the second phase as $Y_2$O$_3$ and orthorhombic-YMnO$_3$ were shown. The annealing ambient and pressure on the crystallinity of YMnO$_3$ thin films is very important. The C-V characteristics have a hysteresis curve with a clockwise rotation, which indicates ferroelectric polarization switching behavior. When the gate voltage sweeps from +5 to 5 V, the memory window of the Pt/YMnO$_3$/Y$_2$O$_3$/Si gate capacitor annealed at 85$0^{\circ}C$ is 1.8 V. The typical leakage current densities of the films annealed in oxygen and vacuum ambient are about 10$^{-3}$ and 10$^{-7}$ A/cm$^2$ at applied voltage of 5 V.

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Catalytic Oxidation of Toluene Using NiO Filter Supported on Carbon Fiber

  • Sim, Jong Ki;Seo, Hyun Ook;Jeong, Myung-Geun;Kim, Kwang-Dae;Nam, Jong Won;Kim, Young Dok;Lim, Dong Chan
    • Proceedings of the Korean Vacuum Society Conference
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    • 2013.02a
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    • pp.217-217
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    • 2013
  • Carbon-fiber-supported NiO catalytic filters for oxidation of volatile organic compounds were prepared by electroless Ni-P plating and subsequent annealing processes. Surface structure and crystallinity of NiO film on carbon fiber could be modified by post-annealing at different temperatures (500 and $650^{\circ}C$. Catalytic thermal decompositions of toluene over these catalytic filters were investigated. $500^{\circ}C$ annealed sample showed a higher catalytic reactivity toward toluene decomposition than $650^{\circ}C$ annealed one under same conditions, despite of its lower surface area and toluene adsorption capacity. X-ray diffraction and X-ray photoelectron spectroscopy studies suggested that amorphous structures of NiO on $500^{\circ}C$ annealed catalyst caused the higher reactivity for oxidation of toluene than that of $650^{\circ}C$ annealed sample with a higher crystallinity.

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Effects of Vacuum Annealing on the Optical Properties of Sputtered Vanadium Oxide Thin Films (스퍼터된 바나듐 산화막의 광학적 특성에 미치는 진공 어닐링의 효과)

  • Lee, Seung-Chul;Whang, In-Soo;Choi, Bok-Gil;Choi, Chang-Kyu;Kim, Sung-Jin
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2003.07b
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    • pp.783-786
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    • 2003
  • Thin films of vanadium oxide(VOx) have been deposited by r.f. magnetron sputtering from $V_2O_5$ target in gas mixture of argon and oxygen. The oxygen/(oxygen+argon) partial pressure ratio of 0% and 8% is adopted. Crystal structure and optical properties of films sputter-deposited under different oxygen gas pressures and in situ annealed in vacuum at $400^{\circ}C$ for 1h and 4h are characterized through XRD and optical absorption measurements. The films as-deposited are amorphous, but $0%O_2$ films annealed for time longer than 4h and $8%O_2$ films annealed for time longer than 1h are polycrystalline. The optical transmission of the films annealed in vacuum decreases considerably than the as-deposited films and the optical absorption of all the films increases rapidly at wavelength shorter than about 550nm. Indirect and direct optical band gaps were decreased with increasing the annealing time.

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Study on the Electrical Characteristic of Low-k SiOC films due to the Appropriate Annealing Temperature (저 유전체 SiOC 박막의 열처리 공정 온도에 따른 전기적인 특성에 관한 연구)

  • Oh, Teresa
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.48 no.8
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    • pp.1-4
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    • 2011
  • This study was the coorrelation between the electrical properties and the dielectric constant of organic inorganic hybrid type low k SiOC film. SiOC film as low-k films was deposited by the chemical vapor deposition and then annealed at 30 $0{\sim}500^{\circ}C$ to find out the properties of the depending on the temperature and polarity. SiOC film decreased the dielectric constant after annealing process, and the electrical properties were improved at the sample annealed at $400^{\circ}C$. From the XRD patterns, there were two kinds of bonding structures in SiOC film. There was the difference in the bonding structure between the samples annealed under $300^{\circ}C$ and the samples annealed over $400^{\circ}C$. The change was confirmed near $400^{\circ}C$.

A Study on the Drawing and Rupture of Uniaxial Stretched Polyvinylalcohol Film in Water (수중 일축신장 플리비닐알콜 필름의 연신과 파단에 관한 연구)

  • Kim, Wan-Soo;Lee, Kwang-Bae;Matsumoto, Kiyoichi
    • Journal of the Korean Society of Clothing and Textiles
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    • v.13 no.4
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    • pp.427-436
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    • 1989
  • Poly (vinyl alcohol) films, which .were annealed at various different annealing conditions, were carried out by uniaxial stretching them with free width in water and were investigated drawing behaviours and rupture phenomena. l) After dipping the specimen into the water, it took about 15 min. for the specimen's swelling to approach to equilibrium. 2) When the film annealed at $180^{\circ}C$ for 10 min. was drawn at $20^{\circ}C$. it was shown very toughness. 3) By means of birefringence measurements, the total molecular orientation of the annealed films increased until the draw ratio of 4, but drawing them above the draw ratio of 5, that of untreated films increased. 4) In the case of the mechanical properties of the drawn films. the annealed films tended to good trend for the draw ratios between 1 and 4. but drawing them above the draw ratio of 5. the untreated films tended to good trend for them.

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