• 제목/요약/키워드: ZrCo

검색결과 633건 처리시간 0.023초

CoZrNb막의 주파수에 따른 임피던스의 변화 (Impedance of CoZrNb Film as a Function of Frequency)

  • 허진;김영학;신광호;박경일;사공건
    • 한국전기전자재료학회:학술대회논문집
    • /
    • 한국전기전자재료학회 2002년도 하계학술대회 논문집 Vol.3 No.2
    • /
    • pp.778-781
    • /
    • 2002
  • MI(Magneto-Impedance) sensor which is made by thin films has significantly high detecting sensitivity in weak magnetic field. It also has a merit to be able to build in the low power system. Its structure is simple, which makes it easier to prepare a miniature. In this study, its magnetic permeability and anisotropy field$(H_k)$ as a function of a thickness of sputtered amorphous CoZrNb films with zero-magnetostriction and excellent soft magnetic property are investigated. In order to make a uniaxial anisotropy, film was subjected to the post annealing in a static magnetic field with 1KOe intensity at 250, 300, and $320^{\circ}C}$ respectively for 2 hours. Anisotropy field$(H_k)$ of film is measured by using a MH loop tracer. Its magnetic permeability of a film is measured over the frequency range from 1 MHz to 750MHz. It has shown that the magnetic permeability of amorphous CoZrNb film is decreased due to the skin effect with increasing a thickness of the CoZrNb film, and hence its driving frequency is lowered. And, it was examined on the permeability and impedance to fabricate the MI sensor which acts at a low frequency by thickening a CoZrNb film relatively.

  • PDF

Development of Monolithic Catalyst System with Co-Ru-Zr for CO2 (dry) Reforming of Methane : Enhanced Coke Tolerance

  • Kim, Hyojin;You, Young-Woo;Heo, Iljeong;Chang, Tae-Sun;Hong, Ji Sook;Lee, Ki Bong;Suh, Jeong Kwon
    • 청정기술
    • /
    • 제23권3호
    • /
    • pp.314-324
    • /
    • 2017
  • To verify the viability of Co, Ru and Zr-based catalyst for $CO_2$ (dry) reforming reaction, catalysts were fabricated using cordierite, silicon carbide and rota monolithic substrates, and they were compared with the conventional $Co-Ru-Zr/SiO_2$ catalyst in terms of performance and durability. Cordierite monolith was showed high activity with the least amount of active component. In addition, when Cordierite monolith was coated with Co-Ru-Zr in various ways, most excellent performance was showed at a precursor solution coating method. In particular, when 0.9 wt% Co-Ru-Zr/Cordierite was used for reaction, it was observed that 95% $CO_2$ conversion was maintained for 300 h at $900^{\circ}C$.

Mechanochemical Process로 제조된 LiCoO2의 전기화학적 특성 (Electrochemical Properties of LiCoO2 Prepared by Mechanochemical Process)

  • 조병원;이중기;이재룡;김수진;이관영;나병기
    • Korean Chemical Engineering Research
    • /
    • 제46권1호
    • /
    • pp.69-75
    • /
    • 2008
  • Mechanochemical process로 제조된 $LiCoO_2$ 전극의 경우에 4.3 V 이상의 전위영역에서 용량감소현상이 두드러지게 나타난 반면에, Zr을 피복한 $LiCoO_2$의 경우에는 4.5 V의 전위에서도 안정성을 유지하였다. 본 연구에서 제작한 Zr이 피복된 $LiCoO_2$ 전극은 3.0~4.5 V 구간에서 197 mAh/g의 용량을 나타내었으며, 50 사이클 후에 96%의 방전용량을 유지하므로 전지의 안정성을 확보하였다.

질화 지르코늄 코팅이 코발트 크롬 합금과 타이타늄 합금에서 의치상 레진과의 전단결합강도에 미치는 영향 (The effect of Zirconium Nitride coating on shear bond strength with denture base resin in Co-Cr alloy and titanium alloy)

  • 박찬;이경훈;임현필
    • 구강회복응용과학지
    • /
    • 제32권3호
    • /
    • pp.194-201
    • /
    • 2016
  • 목적: 본 연구는 Co-Cr, Ti-6Al-4V 합금에 Zirconium Nitride (이하 ZrN) 적용 시, 의치상 레진과의 접착력을 비교하는 것이다. 연구 재료 및 방법: Co-Cr, Ti-6Al-4V 디스크(직경 10 mm, 두께 2.5 mm)를 각각 14개씩 제작하였고, ZrN 코팅에 따라 2개의 그룹으로 나누었다. Primer로 시편 전처리 후, 의치상 레진(직경 6 mm, 두께 5 mm)을 부착하였다. 표면 측정기를 이용하여 시편의 거칠기를 측정한 후, 만능 시험기를 이용하여 전단결합강도를 측정하였으며, 이원분산분석으로 통계 분석하였다. 시편 표면과 파절 양상을 주사전자현미경을 이용하여 관찰하였다. 결과: ZrN을 코팅한 시편에서 유의하게 높은 표면 거칠기를 나타내었고(P < 0.05), 전단결합강도는 낮았다(P < 0.001). ZrN 코팅 시편에서는 혼합성 파절과 부착성 파절이 함께 나타났다. 결론: Co-Cr, Ti-6Al-4V 합금에서 ZrN 코팅 처리는 의치상 레진과의 결합력을 약화시켰다.

공침법으로 제조한 $ZrO_2$+3m/o $Y_2O_3$계 분체의 특성(I) : 정방정 Zirconia분체의 안정성 (Properties of the System $ZrO_2$+3m/o $Y_2O_3$ Powder Prepared by Co-precipitation Method(I) : Stability of Tetragonal ZrO2 Powder)

  • 홍기곤;이홍림
    • 한국세라믹학회지
    • /
    • 제27권3호
    • /
    • pp.361-368
    • /
    • 1990
  • The properties of the powder of ZrO2+3m/o Y2O3 system prepared by co-precipitation method at the pH values of 7, 9, 10 and 11 were investigated. ZrOCl2.8H2O and YCl3.6H2O were used as starting materials and NH4OH as a precipitation agent. Zirconium hydroxide near by Zr(OH)4 structure showed more excellent crystallinity and lower formation temperature of tetragonal ZrO2. In the range of this study, cubic ZrO2 was not formed and stability of tetragonal ZrO2 prepared in the conditiion of pH 7 was most excellent. Average particle sizes and specific surface areas of tetragonal ZrO2 powders, prepared as calcining amorphous zirconium hydroxides at $600^{\circ}C$ for 1h, were 0.6-0.8${\mu}{\textrm}{m}$ and 45-70$m^2$/g, respectively.

  • PDF

고체산화물 연료전지용 (La, Sr)$MnO_3$ 양극에 대한 Co 첨가효과 (Effect of Co Dopant on the (La, Sr)$MnO_3$ Cathode for Solid Oxide Fuel Cell)

  • 김재동;김구대;이기태
    • 한국세라믹학회지
    • /
    • 제37권6호
    • /
    • pp.612-616
    • /
    • 2000
  • The effect of Co dopant on the (La, Sr)MnO3 cathode was investigated. La2Zr2O7 and SrZrO3 were formed as the reaction products between YSZ and LSMC. The reactivity of LSMC with YSZ increased with increasing Co content. However, the cathodic polarization resistance decreased with increasing Co doping. Therefore, doping Co at Mn site in the (La, Sr)MnO3 cathode was effective on controlling the polarization resistance of the cathode. The polarization property of LSMC-YSZ composite(60 wt%: 40 wt%) cathode was better than that of LSMC single cathode.

  • PDF