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Sol-Gel Synthesis and Transport Properties of $La_{2/3}Sr_{1/3}Mn_{0.99}{^{57}}Fe_{0.01}O_3$Granular Thin Films

  • Shim, In-Bo;Kim, Sung-Baek;Ahn, Geun-Young;Yun, Sung-Roe;Cho, Young-Suk;Kim, Chul-Sung
    • Journal of Magnetics
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    • 제6권1호
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    • pp.1-4
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    • 2001

  • We have used acetic acids ethanol and distilled water as a solvent to synthesize $La_{2/3}Sr_{1/3}Mn_{0.99}{^{57}}Fe_{0.01}O_3$(LSMFO) precursor. Crack-free LSMFO granular polycrystalline thin films have been deposited on thermally oxidized silicon substrates by spin coaling. The dependence of crystallization, surface morphology, magnetic and transport properties on annealing temperature was investigated. With increasing annealing temperature, the metal-semiconductor (insulator) transition temperature and the magnetic moment decrease while the resistivity increases. The lattice constants remain almost unchanged. For LSMFO thin films, spin-dependent interfacial tunneling and/or scattering magnetoresistance were observed. Our results indicate that the annealing temperature is very important in determining the intrinsic and extrinsic magnetotransport properties.

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GROWTH AND CHARACTERIZATIONS OF $La_3Ga_5SiO_{14}$ SINGLE CRYSTALS AND SINTERED BODY FOR THE APPLICATIONS OF FILER AND RESONATOR

  • Jung, Il-Hyoung;Kyung Joo;Shim, Kwang-Bo;Auh, Keun-Ho
    • 한국결정성장학회:학술대회논문집
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    • 한국결정성장학회 1998년도 PROCEEDINGS OF THE 15TH KACG TECHNICAL MEETING-PACIFIC RIM 3 SATELLITE SYMPOSIUM SESSION 4, HOTEL HYUNDAI, KYONGJU, SEPTEMBER 20-23, 1998
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    • pp.73-77
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    • 1998

  • Langasite(La3Ga5SiO14) is a new piezoelectric material which is similar to quartz, LN(LiNbO3) and LT(LiTaO3) in its acoustic behavior. In this study, pure Langasite and Langasite family groups were synthesized by the solid state reactions in air. For the synthesis process, diffusion species were investigated and sintered body of synthesized powders were studied on dielectric property according to surface microstructures.

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Fuel-Borne Catalyst와 Perovskite로 구성된 복합촉매 시스템에 의한 디젤 탄소입자상 물질의 연소반응: 반응성능과 Perovskite 촉매조성 (La1-x A'xBO3: A' = K, Sr; 0 ≤ x ≤ 1; B = Fe, Cr, Mn)의 상관관계 (Combustion of Diesel Particulate Matters under Mixed Catalyst System of Fuel-Borne Catalyst and Perovskite: Influence of Composition of Perovskite (La1-x A'xBO3: A' = K, Sr; 0 ≤ x ≤ 1; B = Fe, Cr, Mn) on Combustion Activity)

  • 이대원;성주영;이관영
    • Korean Chemical Engineering Research
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    • 제56권2호
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    • pp.281-290
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    • 2018

  • 최근 선진국을 중심으로 고연비-저배출 내연기관 (디젤) 자동차 보급의 필요성이 대두되면서 기존 촉매후처리 장치의 저온성능 강화를 위한 기술적 방안들이 시급히 요구되고 있다. 본 논문에서는 디젤엔진 배출 탄소입자상 물질의 연소반응에 있어 연료함유 촉매(Fuel-Borne Catalyst)와 페로브스카이트(Perovskite)의 복합촉매 시스템이 보이는 상용모델촉매 대비 우수한 저온 연소성능과 이의 Perovskite 촉매 조성에 대한 의존성에 관해 논하였다. Fe/Ce 계열 연료함유 촉매가 A-site 원소(La)에 K이 부분치환되고, B-site 금속이 Fe인 Perovskite 촉매와 복합화될 때 상대적으로 우수한 저온 연소성능 개선효과가 관찰되었다. 이를 관찰하기 위해 연료함유 촉매가 함유되거나 함유하지 않은 탄소 입자상 물질과 다양한 조성의 La 계열 Perovskite 촉매를 혼합한 고정층에 대한 온도상승 산화반응 실험(Temperature-Programmed Oxidation)을 수행하였으며, 이산화탄소 생성과 질소산화물 농도 저하 패턴의 연동특성을 통해 두 촉매의 상호 연계작용을 유추하였다.

  • https://doi.org/10.9713/kcer.2018.56.2.281 인용 PDF KSCI

Li과 B이 포함된 폴리머 전구체의 열처리에 의한 Li7La3Zr2O12 고체전해질의 소결조제 합성 (Preparation of Sintering Aid for Li7La3Zr2O12 Solid Electrolyte by Heat-treatment of Polymeric Precursors Containing Li and B)

  • 신란희;류성수
    • 한국분말재료학회지
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    • 제25권2호
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    • pp.151-157
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    • 2018

  • In this study, the compound $Li_3BO_3$ (LBO) is intended to be prepared by a polymeric complex method as a sintering aid for the densification of $Li_7La_3Zr_2O_{12}$ (LLZ) solid electrolyte. A polymeric precursor containing Li and B is heat-treated in an air atmosphere at a temperature range between $600^{\circ}C$ and $800^{\circ}C$. Instead of LBO, the compound $Li_{2+x}C_{1-x}B_xO_3$ (LCBO) is unexpectedly synthesized after a heat-treatment of $700^{\circ}C$. The effect of LCBO addition on sintering behavior and ion conductivity of LLZ is studied. It is found that the LCBO compound could lead to significant improvements in the densification and ionic conductivity of LLZ compared to pure LLZ. After sintering at $1100^{\circ}C$, the density of the LLZ-12wt%LBO composite is $3.72g/cm^3$, with a high Li-ion conductivity of $1.18{\times}10^{-4}Scm^{-1}$ at $28^{\circ}C$, while the pure LLZ specimen had a densify of $2.98g/cm^3$ and Li-ion conductivity of $5.98{\times}10^{-6}Scm^{-1}$.

  • https://doi.org/10.4150/KPMI.2018.25.2.151 인용 PDF KSCI

The Project of about Distinguishing of Modern Clothing after 21c Iraq War

  • Yang, Bo-La;Lim, Young-Ja
    • 한국복식학회:학술대회논문집
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    • 한국복식학회 2003년도 International Costume Conference
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    • pp.52-52
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    • 2003

  • As clothing, fashion is changed by life circumstance, reform of social custom, condition of economy, inner or outside every accident and complicately psychologic a main cause work. But definite and great accident like revolution or War is originated. The War effect in clothing, eating, housing life, specially social culture affect social culture have an affect.

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