통합 검색 | Korea Science

Cao, Shiyu;Song, Shangbin;Xiang, Xing;Hu, Qing;Zhang, Chi;Xia, Ziwen;Xu, Yinghui;Zha, Wenping;Li, Junyang;Gonzale, Paulina Mercedes;Han, Young-Hwan;Chen, Fei
- 한국세라믹학회지
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- 제56권2호
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- pp.111-129
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- 2019
Recently, all-solid-state batteries (ASSBs) have attracted increasing interest owing to their higher energy density and safety. As the core material of ASSBs, the characteristics of the solid electrolyte largely determine the performance of the battery. Thus far, a variety of inorganic solid electrolytes have been studied, including the NASICON-type, LISICON-type, perovskite-type, garnet-type, glassy solid electrolyte, and so on. The garnet Li₇La₃Zr₂O₁₂ (LLZO) solid electrolyte is one of the most promising candidates because of its excellent comprehensively electrochemical performance. Both, experiments and theoretical calculations, show that cubic LLZO has high room-temperature ionic conductivity and good chemical stability while contacting with the lithium anode and most of the cathode materials. In this paper, the crystal structure, Li-ion transport mechanism, preparation method, and element doping of LLZO are introduced in detail based on the research progress in recent years. Then, the development prospects and challenges of LLZO as applied to ASSBs are discussed.
https://doi.org/10.4191/kcers.2019.56.2.01 인용 PDF KSCI

Sunghwan Jin;Yu, Se-Gi;Jungna Heo;Taewon Jeong;Lee, Junghee;Whikun Yi;Park, Yongsoo;Kim, Jongmin
- Journal of Korean Vacuum Science & Technology
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- 제4권4호
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- pp.93-96
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- 2000
Microchannel plates (MCPs) have been developed by introducing new materials and process technologies. Main body was made of alumina by programmable punching, laminating, and firing. The channel walls of pore arrays of an MCP were deposited with thin films by electroless copper plating and sol-gel process. Our MCP has advantages such as easy fabrication, durability, high temperature endurance, and applicability to the large size comparing with the conventional MCPs. Experiments on the brightness of an MCP incorporated FED revealed that the FED with a MCP is three to four times brighter than a conventional FED. Moreover, the focusing in a FED is improved. Incorporating an MCP into a FED is one of promising methods to enhance the characteristics of the FED. In addition, amplification yield of the MCP is measured for varying the aspect ratio and the input current.
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Sun, J.H.;Kim, J.H.;Ahn, B.G.;Park, S.Y.;Jung, E.J.;Lee, J.H.;Kang, H.C.
- 한국진공학회:학술대회논문집
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- 한국진공학회 2011년도 제40회 동계학술대회 초록집
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- pp.72-72
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- 2011
Recently, Zinc oxide (ZnO) nano-structures have been received attractive attention because of their outstanding optical and electrical properties. It might be a promising material considered for applications to photonic and electronic devices such as ultraviolet light emitting diode, thin film transistor, and gas sensors. ZnO nano-structures can be typically synthesized by the VLS growth mode and self-assembly. In the VLS growth mode using various growth techniques, the noble metal catalysts such as Au and Sn were used. However, the growth of ZnO nano-structures on nano-crystalline Au seeds using radio frequency (RF) magnetron sputtering might be explained by the profile coating, i.e. the ZnO nano-structures were a morphological replica of Au seeds. Ga doped ZnO (ZnO:Ga) nano-structures using this concept were synthesized and characterized by XRD, AFM, SEM, and TEM. We found that surface morphology is drastically changed from initial islands to later sun-flower typed nano-structures. We will present the structural evolution of ZnO:Ga nano-structures with increasing the film thickness.
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Boran Kong ;Kaijie Zhu ;Han Zhang ;Chen Hao ;Jiong Guo ;Fu Li
- Nuclear Engineering and Technology
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- 제55권4호
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- pp.1350-1364
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- 2023
2D/1D coupling method is an important neutron transport calculation method due to its high accuracy and relatively low computation cost. However, 2D/1D coupling method may diverge especially in small axial mesh size. To analyze the convergence behavior of 2D/1D coupling method, a Fourier analysis for k-eigenvalue neutron transport problems is implemented. The analysis results present the divergence problem of 2D/1D coupling method in small axial mesh size. Several common attempts are made to solve the divergence problem, which are to increase the number of inner iterations of the 2D or 1D calculation, and two times 1D calculations per outer iteration. However, these attempts only could improve the convergence rate but cannot deal with the divergence problem of 2D/1D coupling method thoroughly. Moreover, the choice of axial solvers, such as DGFEM SN and traditional SN, and its effect on the convergence behavior are also discussed. The results show that the choice of axial solver is a key point for the convergence of 2D/1D method. The DGFEM SN based 2D/1D method could converge within a wide range of optical thickness region, which is superior to that of traditional SN method.
https://doi.org/10.1016/j.net.2022.12.034 인용 PDF