• 제목/요약/키워드: Electron Microscopy

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Review on Electronic Correlations and the Metal-Insulator Transition in SrRuO3

  • Pang, Subeen
    • Applied Microscopy
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    • 제47권3호
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    • pp.187-202
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    • 2017
  • The classical electron band theory is a powerful tool to describe the electronic structures of solids. However, the band theory and corresponding density functional theory become inappropriate if a system comprises localized electrons in a scenario wherein strong electron correlations cannot be neglected. $SrRuO_3$ is one such system, and the partially localized d-band electrons exhibit some interesting behaviors such as enhanced effective mass, spectral incoherency, and oppression of ferromagnetism and itinerancy. In particular, a Metal-Insulator transition occurs when the thickness of $SrRuO_3$ approaches approximately four unit cells. In the computational studies, irrespective of the inclusion of on-site Hubbard repulsion and Hund's coupling parameters, correctly depicting the correlation effects is difficult. Because the oxygen atoms and the symmetry of octahedra are known to play important roles in the system, scrutinizing both the electronic band structure and the lattice system of $SrRuO_3$ is required to find the origin of the correlated behaviors. Transmission electron microscopy is a promising solution to this problem because of its integrated functionalities, which include atomic-resolution imaging and electron energy loss spectroscopy.

개구리 피부의 세포접착부에 관한 전자 현미경적 연구 (Electron Microscopy of the Intercellular Junction of Frog (Rana temporaria) Skin)

  • 윤종식;장승한;최금덕
    • Applied Microscopy
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    • 제1권1호
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    • pp.19-26
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    • 1969
  • 개구리(Rana temperaria) 상피조직의 세포간 접착부위를 전자현미경으로 관찰하였다. 새로운 절편방법을 시도하여 동 부위의 초미세구조를 밝혔으며, 세가지 세포간간 접착방법중 하나인 데스모솜(Desmosome)은 상피세포 원형질막을 따라 절서있고 빈번하게 배열되어 있음을 처음으로 밝혀냈다. 본 연구 및 관찰결과와 관련하여 피부 암세포의 성장기 전 과의 관계를 논의하였다.

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