• 제목/요약/키워드: metallic phase

검색결과 319건 처리시간 0.031초

Crystallization in Li$_2$O-A1$_2$O$_3$-SiO$_2$ Glass induced by 355 nm Nd:YAG Laser Irradiation

  • Lee, Yong-Su;Kang, Won-Ho
    • 마이크로전자및패키징학회지
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    • 제7권2호
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    • pp.43-46
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    • 2000
  • Nd:YAG laser of 355 nm wavelength, which amounts to 3.5 eV, produced by a harmonic generator was used to create Ag metallic particles as seeds for nucleation in photosensitive glass containing $Ag^+$ and $Ce^{3+}$ . The pulse widths and frequency of the laser were 8ns and 10 Hz, respectively. For crystalline growth, heat-treatment following laser irradiation was carried out at $570^{\circ}C$ for 1h. Then, the $LiAlSi_3O^8$ crystal phase appeared in the laser irradiated lithium aluminum silicate glass. We present the effect of laser-induced nucleation compared with spontaneous nucleation by heat treatment fur crystallization in the glass.

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Characterization of Ni Oxide Nanofibers by Electrospinning

  • 박주연;고성위;강용철
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
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    • pp.379.2-379.2
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    • 2016
  • The Ni oxide/PVP nanofibers were synthesized by sol-gel and electrospinning technique. The obtained Ni oxide/PVP (polyvinylpyrrolidone) nanofibers were calcined to remove the PVP compound at 873 and 1173 K. The Ni oxide/PVP nanofibers were analyzed by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The SEM images showed that the mat form was prepared by calcination of Ni oxide/PVP nanofibers at 873 K. And the crystal structure of Ni oxide at 1173 K was also confirmed by SEM images. XRD results shows the crystallinity of metallic Ni and NiO. TEM images also verified the crystal phase of Ni and Ni oxide. XP spectra revealed that the oxidation state of Ni to conclude the chemical composition of Cu oxide nanofibers.

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금속 염 첨가 방법을 이용하여 사출성형된 텅스텐 중합금의 소결거동 (Sintering Behavior of the Injection Molded W-Ni-Fe Heavy Alloy by Addition of Metallic Stat)

  • 김대건;류성수;김은표;이정근;김영도;문인형
    • 한국분말재료학회지
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    • 제6권4호
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    • pp.294-300
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    • 1999
  • This study was carried out to investigate the possibility whether Metal Injection Molding (MIM) process could be applied to 95wt.%W-3.5wt.%Ni-1.5wt.%Fe heavy alloy in order to obtain an intricate shape. Methylcellulose was used in the injection molding for binder. $FeCl_2-4H_2O$ was added in solvent substituting Fe powder and $FeCl_2$ was doped on W-Ni premixed powder. When $FeCl_2-4H_2O$ was added in solvent, the binder separation occurred for injection molding so that the matrix content was changed. Such problem was solved when $FeCl_2$ was doped. In this study. the debinding process did not affect residual carbon content. The sintered microsouctures as addition methods of Fe element and the sintering temperature from $1420^{\circ}C$ to $1470^{\circ}C$, which are around the temperature of liquid phase formation, were observed.

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금속환원법에 의한 바나듐 분말 추출 (Extraction of Vanadium Powder by Metallothermic Reduction)

  • 이동원;허상현;염종택;왕제필
    • 한국분말재료학회지
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    • 제20권1호
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    • pp.43-47
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    • 2013
  • The extraction of metallic pure vanadium powder from raw oxide has been tried by Mg-reduction. In first stage, $V_2O_5$ powders as initial raw material was reduced by hydrogen gas into $V_2O_3$ phase. $V_2O_3$ powder was reduced in next stage by magnesium gas at 1,073K for 24 hours. After reduction reaction, the MgO component mixed with reduced vanadium powder were dissolved and removed fully in 10% HCl solution for 5 hours at room temperature. The oxygen content and particle size of finally produced vanadium powders were 0.84 wt% and 1 ${\mu}m$, respectively

Directional Radiation of Surface Plasmon Polaritons at Visible Wavelengths through a Nanohole Dimer Optical Antenna Milled in a Gold Film

  • Janipour, Mohsen;Hodjat-Kashani, Farrokh
    • Journal of the Optical Society of Korea
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    • 제18권6호
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    • pp.799-808
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    • 2014
  • The mechanism of optical interaction of two nanoholes, milled in an opaque gold film, by means of surface plasmon polariton (SPP) propagation is investigated. The interaction depends on the polarization direction of the incident light when the nanohole pair is illuminated through uniform single antenna excitations. It is shown that by illuminating one of the nanoholes, under single antenna excitation, the other nanohole can be excited indirectly via propagated SPPs from the excited nanohole. In addition, it is found that the spectrum of electromagnetic power above the surface of the metallic film at an arbitrary point along the axis of the nanohole pair presents two resonant peaks. These peaks are due to the optical interaction between nanoholes, where the short- and long-wavelength peaks can be assigned to in-phase and antiphase interactions of magnetic dipoles relative to each nanohole, respectively. The magnetic coupled dipole approximation (MCDA) method confirms the simulation results.

Crystallization in Li20-A1203-Si02 Glass induced by 355nm Nd:YAG Laser Irradiation

  • Lee, Yong-Su;Kang, Won-Ho;Song, Sun-Dal
    • 한국마이크로전자및패키징학회:학술대회논문집
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    • 한국마이크로전자및패키징학회 2000년도 Proceedings of 5th International Joint Symposium on Microeletronics and Packaging
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    • pp.112-117
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    • 2000
  • Nd:YAG laser of 355nm wavelength, which amounts to 3.5eV, produced by a harmonic generator was used to create Ag metallic particles as seeds for nucleation in photosensitive glass containing Ag+ and Ce3+. The pulse widths and frequency of the laser were 8ns and 10Hz, respectively. For crystalline growth, heat-treatment following laser irradiation was carried out at $570^{\circ}C$ fur 1h. Then, the LiAlSi3O8. crystal phase appeared in the laser irradiated lithium aluminum silicate glass. We present the effect of laser-induced nucleation compared with spontaneous nucleation by heat treatment for crystallization in the glass.

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Indium-silver alloy를 이용한 접합의 특성 (The characteristics of joints with In-Ag alloy)

  • 김재욱;김제윤;김상식;성만영
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2003년도 하계학술대회 논문집 Vol.4 No.1
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    • pp.256-258
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    • 2003
  • Two Si wafers are bonded with indium-silver alloy using diffusion bonding method. When silver and indium thin films are contacted, they diffuse into each other and form inter-metallic compounds like $AgIn_2$, $Ag_2In$, $Ag_3In$ etc. These compounds are determined by ratio of two metals. From phase diagram of Ag-In alloy, we can get the ratio of $Ag_2In$, that has high melting point about 700$^{\circ}C$, approximately 2:1. This ratio was made by controlling of film thickness. And bonding was executed by annealing and adding pressures at a time. The joint of these wafers had been observed by SEM. And we had also seen the EDS (Energy Dispersive Spectroscopy) data to analysis the component of samples.

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$LaNiO_3$전도성 세라믹의 합성과 도전특성 (Synthesis and Conductivity Properties of $LaNiO_3$ Ceramic Conductors)

  • 조정호;조주현;김강언;정수태
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2001년도 추계학술대회 논문집 Vol.14 No.1
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    • pp.406-409
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    • 2001
  • The conductivity properties and synthesis of $LaNiO_{3}$ ceramics from $La_{1+\delta}NiO_{3}(\delta=-0.06,0,0.06)$ were investigated. A single perovskite phase was realized at $800^{\circ}C$. $La_{2}NiO_{4}$ and other unexpected oxide were observed at $1000^{\circ}C$. The Microstructure was showed clearly that it is a low density porous material. $LaNiO_3$ ceramic showed a metallic conductivity. The conductivity of La rich samples had a higher value than the La poor samples.

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비정질 Zr-V-Ti 합금분말의 결정화에 따른 게터 특성 변화 (Changes of Getter properties by Crystallization of Amorphous Zr-V-Ti alloy Powders)

  • 박제신;김원백;백진선
    • 한국분말재료학회지
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    • 제14권1호
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    • pp.50-55
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    • 2007
  • The hydrogen sorption speeds of $Zr_{57}V_{36}Ti_7$ amorphous alloy and its crystallized alloys were evaluated at room temperature. $Zr_{57}V_{36}Ti_7$ amorphous alloy was prepared by ball milling. The hydrogen sorption rate of the partially crystallized alloy was higher than that of amorphous. The enhanced sorption rate of partially crystallized alloy was explained in terms of grain refinement that has been known to promote the diffusion into metallic bulk of the gases. The grain refinement could be obtained by crystallization of amorphous phase resulting in the observed increase in sorption property.

Fe$^{0}$ 과 계면활성제를 이용한 PCE의 탈염소화 반응에 관한 연구 (Dechlorination of PCE Using Zero-Valent Iron and Surfactants)

  • 조현희;박재우
    • 한국지하수토양환경학회:학술대회논문집
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    • 한국지하수토양환경학회 2000년도 추계학술대회
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    • pp.119-123
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    • 2000
  • In-situ treatment technologies have been proposed to transform or remove pollutants from contaminated groundwater. Zero-valent iron(Fe$^{0}$ ), metallic iron, is being evaluated as a permeable reactive material to retard the transport of wide array of highly mobile contaminants in groundwater. In this research, tetrachloroethylene(PCE) dechlorination by powdered zero-valent iron in buffered aqueous solution was studied with and without the presence of surfactants. The rate of dechlorination of PCE by zero-valent iron with surfactant was much higher than without surfactant. The presence of surfactant increased the apparent rate of dechlorination because the surfactants influenced the dissolution of PCE into the aqueous phase.

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