• 제목/요약/키워드: Solid State

검색결과 3,450건 처리시간 0.037초

Nanosecond Laser Cleaning of Aluminum Alloy Oxide Film

  • Hang Dong;Yahui Li;Shanman Lu;Wei Zhang;Guangyong Jin
    • Current Optics and Photonics
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    • 제7권6호
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    • pp.714-720
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    • 2023
  • Laser cleaning has the advantages of environmental protection, precision, and high efficiency, and has good prospects for application in removing oxide films on the surface of aluminum alloy. This paper discusses the cleaning threshold and cleaning mechanism of aluminum alloy surface oxide film. A nanosecond pulsed laser was used to remove a 5-㎛-thick oxide film from the surface of 7A04 aluminum alloy, and the target surface temperature and cleaning depth were simulated. The effects of different laser energy densities on the surface morphology of the aluminum alloy were analyzed, and the plasma motion process was recorded using a high-speed camera. The temperature measurement results of the experiment are close to the simulation results. The results show that the laser cleaning of aluminum alloy oxide film is mainly based on the vaporization mechanism and the shock wave generated by the explosion.

Chemical Shift and Quadrupolar Interactions in Solids

  • Kim Jin-Eun
    • 한국자기공명학회논문지
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    • 제10권1호
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    • pp.1-37
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    • 2006
  • General expressions for solid state NMR lines are described for transitions under static, magic angle spinning, and variable angle spinning conditions in the case where the principal axis system for the anisotropic chemical shift tensor is noncoincident with that of the quadrupole coupling tensor. It is demonstrated that solid state NMR powder pattern simulation program VMAS based on the conventional grid point method of integrating over the Euler angle space is fast enough in comparison with the POWDER simulation package and Gauss-point method.

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Cold and Detonation Spraying of $TiB_2-Cu$ Nanocomposites

  • Lomovsky, O.I.;Dudina, D.V.;Korchagin, M.A.;Kosarev, V.F.;Klinkov, S.V.;Ulianitsky, V.Yu.;Kim, J.S.;Kwon, Y.S.
    • 한국분말야금학회:학술대회논문집
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    • 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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    • pp.680.2-680.2
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    • 2006
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Characterization of the Catalytic Heteropoly Compounds using Solid-state NMR

  • Kim, Y;Lee, W
    • 한국자기공명학회논문지
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    • 제1권1호
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    • pp.45-58
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    • 1997
  • Heteropoly compounds, H3PMo12O40, CsxH3-xPMo12O40, and vanadium containing heteropoly compound were characterized by Solid-state broad line 1H MAS NMR, 31P MAS NMR, and High Speed MAS 51V NMR spectroscopy of quadrupolar nuclei. The effects of calcination, dehydration, and the number of protons on the structure of heteropoly compounds were studied. The results of this study demonstrate that these Solid-state NMR techniques are very useful tools to study heteropoly compounds.

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마이크로그리드를 위한 Solid-State Circuit Breaker의 특성 해석 (A Characteristic Analysis of Solid-State Circuit Breaker for Microgird Applications)

  • 김진영;정재헌;김슬기;김인동;노의철;김흥근
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2010년도 추계학술대회
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    • pp.290-291
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    • 2010
  • 도통손실이 작고 경제적인 SCR을 이용하여 마이크로그리드에 적용이 가능한 25 [kVA]급 SSCB(Solid-State Circuit Breaker)를 설계하였다. 시뮬레이션을 통하여 3상 단락 사고시의 SSCB 동작특성을 살펴보았고 계통의 용량에 따른 커패시터의 설계값을 제시하였다.

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3차원 전고체 전극 구조체 형성, 분석 및 성능 예측 기술 동향 (A Review on 3D Structure Formation, Analysis and Performance Prediction Technique for All-solid-state Electrode and Battery)

  • 박주남;진다희;김도환;배경택;이강택;이용민
    • 전기화학회지
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    • 제22권4호
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    • pp.139-147
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    • 2019
  • 고에너지밀도 대용량 리튬이온전지를 채용한 전기자동차 및 에너지저장시스템에서 발생하고 있는 발화사고로 인해, 고안전성 전고체 리튬이차전지(All-solid-state Lithium Secondary Battery, ALSB)에 대한 연구가 국내외에서 활발히 진행되고 있다. 하지만, 단순히 액체전해질을 고체전해질로만 바꾸는 것이 아니라, 이로 인해 수반되는 전극 및 전지 설계와 해석이 크게 달라진다는 점에서 해결해야 될 이슈들이 산재해 있다. 특히, 전지는 전극 설계에 따라 그 성능이 굉장히 상이함에도 불구하고, 실질적인 전고체 전지 실험 구현의 어려움으로 전고체 전극(All-solid-state Electrode, ASSE) 설계에 따른 성능 차이를 체계적으로 비교 분석하여 최적화하는 연구는 매우 제한적이다. 이를 극복하기 위한 방안으로, 가상의 3차원 전고체 전극 구조체를 형성하고, 형성된 구조체를 바탕으로 다양한 성능 결정 파라미터를 도출하며, 더불어 분석 전극을 포함한 전지의 성능까지 예측할 수 있는 기술을 개발하는 연구가 주목을 받기 시작했다. 본 총설에서는 3차원 전고체 전극 구조체 형성부터 전고체 리튬이차전지의 성능을 예측하는 기술까지 각각의 기술들이 갖고 있는 장단점을 폭넓게 다룰 것이며, 나아가 본 기술이 나아갈 최종적인 목표까지 간략히 기술하고자 한다.

리튬금속과 고체전해질의 계면 반응 (Interfacial Reaction between Li Metal and Solid Electrolyte in All-Solid-State Batteries)

  • 김재헌
    • Corrosion Science and Technology
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    • 제22권4호
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    • pp.287-296
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    • 2023
  • Li-ion batteries have been gaining increasing importance, driven by the growing utilization of renewable energy and the expansion of electric vehicles. To meet market demands, it is essential to ensure high energy density and battery safety. All-solid-state batteries (ASSBs) have attracted significant attention as a potential solution. Among the advantages, they operate with an ion-conductive solid electrolyte instead of a liquid electrolyte therefore significantly reducing the risk of fire. In addition, by using high-capacity alternative electrode materials, ASSBs offer a promising opportunity to enhance energy density, making them highly desirable in the automotive and secondary battery industries. In ASSBs, Li metal can be used as the anode, providing a high theoretical capacity (3860 mAh/g). However, challenges related to the high interfacial resistance between Li metal and solid electrolytes and those concerning material degradation during charge-discharge cycles need to be addressed for the successful commercialization of ASSBs. This review introduces and discusses the interfacial reactions between Li metal and solid electrolytes, along with research cases aiming to improve these interactions. Additionally, future development directions in this field are explored.