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881.
H.Y. Byun I.J. Chung Y.-S. Suh H.K. Shim D.Y. Kim C.Y. Kim 《Macromolecular Symposia》2003,192(1):151-160
A blend of a newly synthesized polyfluorene(PDHBF) and polyvinylcarbazole(PVK) exhibits a photoluminescence(PL) emission spectrum of PDHBF without an increase in the PL intensity on photoexcitation at 340 nm, the UV-visible absorption maximum of PVK, despite of a substantial spectrum overlap. However, the indirect photoexcitation of the blend suppresses the secondary emission of the PL with the maximum at 520 nm. The chromophores generating the secondary emission are formed when the chromophores are photoexcited above the critical energy level of an excited state. The chromophores formed by the energy transfer have energy lower than the critical energy and fail to form the excimers. A low temperature PL study of the blend in a cryogenic chamber proves that the energy transfer in the system takes place mainly between the excimers of PVK generated by the partially eclipsed dimeric states of two carbazole units and the fluorophores of PDHBF. 相似文献
882.
J.B. Shim N. Yoshimoto M. Yoshizawa D.H. Yoon 《Crystal Research and Technology》2001,36(11):1209-1214
Erbium (Er3+) doped LiNbO3 single crystal thin films have been grown LiNbO3 (001) substrate by the liquid phase epitaxy method. The crystallinity was determined by high‐resolution X‐ray diffraction. The lattice mismatch between Er3+ doped LiNbO3 films and LiNbO3 (001) substrate was investigated by X‐ray rocking curve analysis. Also we studied the structural characteristics of Er3+ doped LiNbO3 films and surface morphology dependent on the film thickness. 相似文献
883.
Prof. Dr. Sunghun Jung Dr. Joon Kyo Seo Dr. Il-Chan Jang Dr. Jihun Kim Prof. Dr. Jae-Hyun Shim Dr. Jung-Je Woo 《Chemphyschem》2023,24(21):e202300438
We defined four major deterioration factors (electrolyte loss (EL), lithium loss (LL), lithium precipitation (LP), and compound deterioration (CD)). Then, we derived eleven key performance indicators (KPIs) for comparative analysis. After that, we fabricated three deteriorated cells for each of three deterioration factors (EL, LL, and LP) and one cell with CD (for verification) with four individual (dis)charging experiment manuals. The two major contributions of this study are the performance of 1) trend analysis to determine a suitable diagnostic metric by inspecting the eleven KPIs and 2) comparison analysis of and to verify the effectiveness of utilizing as a real-time deterioration diagnostic factor using a concept of model-in-the-loop simulation. The results show that 1) has the most conspicuous trendline tendency among the eleven comparison targets for all four major deterioration factors, and 2) the angle difference between the two trends of and lies within a minimum of 9° and a maximum of 43° (with a sscale on the x-axis and a scale on the y-axis for a clear trend line analysis). From this, we can conclude that the trendline-based real-time deterioration analysis employing may be practically applicable to a limited extent. 相似文献
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