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        검색결과 3

        1.
        2009.10 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        Unreported dielectrics based on the binary system of MgO-SiO2 were investigated as potential candidates for microwave dielectric applications, particularly those demanding a high fired density and high quality factors. Extensive dielectric compositions having different molar ratios of MgO to SiO2, such as 2:1, 3:1, 4:1, and 5:1, were prepared by conventional solid state reactions between MgO and SiO2. 1 mol% of V2O5 was added to aid sintering for improved densification. The dielectric compositions were found to consist of two distinguishable phases of Mg2SiO4 and MgO beyond the 2:1 compositional ratio, which determined the final physical and dielectric properties of the corresponding composite samples. The increase of the ratio of MgO to SiO2 tended to improve fired density and quality factor (Q) without increasing grain size. As a promising composition, the 5MgO.SiO2 sample sintered at 1400 ˚C exhibited a low dielectric constant of 7.9 and a high Q × f (frequency) value of ~99,600 at 13.7 GHz.
        4,000원
        3.
        1998.02 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        Mg2SiO4 열형광체에 란탄계 금속 Tb, Tm, La, Ho, Dy 및 Nd를 활성체로 첨가하여 열형광체를 제작했으며, Peak shape법으로 활성화에너지를 계산한 결과 0.53-1.77eV였으며, 발광과정의 차수는 전부 2차였다. 저 에너지 X-선에 대해 매우 높은 감도를 나타내었으므로 방사선 센서 소자로 개발하기 위한 기초 자료가 될 것이다.
        4,000원