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11.
Hyun Chul Choi Min Kyu Lee Hyun Joon Shin Seung Bin Kim 《Journal of Electron Spectroscopy and Related Phenomena》2003,130(1-3):85-96
To investigate the formation of a solid electrolyte interface (SEI) on the Li1+xV3O8 electrode surface in the thermodynamic stability range of the organic electrolyte, we applied scanning photoelectron microscopy (SPEM) to a pristine electrode and to an electrode after ten cycles. The F K-edge absorption spectrum of the cycled electrode showed that LiF forms on the electrode surface during the lithium insertion–extraction process in the Li1+xV3O8/Li cell. The photoelectron spectrum for the cycled electrode showed intense spectral features corresponding to Li 1s, F 2s, F 2p, and P 2p electron signals, whereas these spectral features were of negligible intensity for the pristine electrode. The above results give strong support for the formation of an SEI that consists of LiF and compounds containing phosphorus during operation of the battery. The SPEM images also revealed that the fluorine distribution on the surface of the cycled electrode was inhomogeneous. 相似文献
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For the methylsilsesquioxane film whose optical birefringence is almost zero, it was recently reported that its vertical thermal expansion coefficient (CTE) was approximately one order of magnitude larger than the lateral CTE. Though the birefringence is not an absolute predictor of anisotropic behavior, the discrepancy in both the CTEs was so remarkable that it was essential to investigate whether the anisotropy was intrinsic property or not. If the effect of Poisson's ratio is considered in the calculation of the vertical CTE and when elastic modulus measured by surface acoustic wave spectroscopy is used in the assessment of the lateral CTE, both the CTEs are coincident with each other. Therefore, it can be concluded that the discrepancy in the CTEs can be attributed to a higher in‐plane polymer chain orientation but it can also arise from the misleadingly assumed modulus and Poisson's ratio. © 2006 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 3109–3120, 2006 相似文献
14.
Seung Min Lee 《Operations Research Letters》2003,31(4):268-272
A continuum structure function is a non-decreasing mapping from the unit hypercube to the unit interval. Within the class of continuum structure functions, new axiomatic characterizations of the Natvig and the Barlow-Wu subclass are obtained. 相似文献
15.
The coapproximation in linear spaces 总被引:2,自引:0,他引:2
Son Wenhua 《分析论及其应用》1993,9(4):55-65
In this paper, we investigate the properties of strongly coapproximation in normed linear spaces and locally convex spaces.
The relations between strongly coapproximation and strongly unique approximation and of the f-coapproximation and f-approximation
are also considered.
Supported by NSFC 相似文献
16.
Kim GN Kim EJ Son D Bacala A Imlay R Kirk P McNeil RR Metcalf W Cheng CP Mao ZP Yan Y Xu YT Zhu YC Abashian A Gotow K Kajino F Low E Naito F Piilonen L Childers R Darden C Lusin S Rosenfeld C Wilson S Frautschi M Kagan H Kass R Trahern CG Ko W Lander RL Maeshima K Malchow RL Higashi JR Kurihara Y Maki A Nozaki T Omori T Perez P Sagawa H Sakai Y Sugimoto Y Takaiwa Y Terada S Tsuchiya K Poling R Green J Park IH Sakamoto S Sannes F Schnetzer S Stone R Trentalange S Zimmerman D Miyano K Miyata H 《Physical review letters》1988,61(8):911-914
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ω-Tetrahydropyran-2-ylsulfanylalkylmagnesium chlorides are prepared as Grignard reagents containing protected mercaptoalkyl chains, which are useful for the direct introduction of ω-mercaptoalkyl chains to electrophiles. In order to prove the usefulness of these reagents, they were reacted with buckminsterfullerene (C60) to give 1-(ω-mercaptoalkyl)-1,2-dihydrobuck minsterfullerenes after the deprotection of THP group with TFA. 相似文献
19.
Five new natural labdane-type diterpenoids (5-9), designated leoheteronins A-E, together with four known diterpenoids (1-4), two phytosterols as a mixture of beta-sitosterol and stigmasterol, and the flavone genkwanin (10) were isolated from the aerial parts of Leonurus heterophyllus SW. (Lamiaceae) collected in northern Vietnam. Compound 1 was isolated for the first time from a Leonurus species, and 10 is considered to be a chemotaxonomic marker of the Leonurus genus. Their structures were determined using spectroscopic analyses. 相似文献
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