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961.
962.
963.
Throughoutthispaper,Gisafinitegroup ,pisaprimeinπ(G) ,andM <·GdenotesthatMisamaximalsubgroupofG .A/BiscalledasectionofGifB A≤G .Therestofnotationsisstandardandtakenmainlyfrom [1 ]and [2 ] . In [3] ,Weilandtprovedthewell knowntheorem :Gissolvableifitcontainstwonilpote… 相似文献
964.
A scheme for all-fiber clock enhancement of non-return-to-zero (NRZ) data based on cross-phase modulation (XPM) effect in nonlinear fibers is proposed and demonstrated in simulation. The simulation results indicate that the clock-to-data ratio of NRZ signals at 64 Gb/s can be increased to 22.94 dB by using this scheme, and the pattern effect in clock enhanced signals is very weak. The ability of high speed operation up to 140 Gb/s of this scheme is also proved in our simulation. 相似文献
965.
966.
YAN HuiJuan LI ShanShan YAN CunJi CHEN Qing & WAN LiJun Beijing National Laboratory for Molecular Sciences 《中国科学B辑(英文版)》2009,(5)
The adsorption and adlayer structures of tetrathiofulvalene (TTF), tetracyanoquinodimethane (TCNQ) and TTF-TCNQ on Au(111) have been systematically investigated by in situ electrochemical scanning tunneling microscopy (ECSTM) and cyclic voltammetry in 0.1 mol?L?1 HClO4. All the three molecules were found to form well-ordered adlayers in the double-layer potential region of Au(111). For TTF and TCNQ adlayers, (6×3) and (4×7) structures have been observed, respectively. A structural transition was observed on... 相似文献
967.
We investigate the confinement properties of bounded, nonnegative, compactly supported vortices of axisymmetric incompressible Euler flows without swirl. We show that along one direction of the symmetry axis, its support can grow no faster than O[(t log t)1/2]. The rate at which it approaches the symmetry axis is also estimated. Together with the result of Maffei–Marchioro on the radial growth rate of the support, it is contained in a slowly expanding tubular region. The techniques of the above‐mentioned authors, Iftimie–Lopes–Nussenzveig and Iftimie–Sideris–Gamblin, are used. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
968.
基于灰色关联分析的财产保险公司偿付能力的模糊综合评判 总被引:2,自引:0,他引:2
为解决财产保险公司的偿付能力的评价问题,建立了基于灰色关联分析的模糊综合评判模型.选取了2003-2005年我国8家财产保险公司的相关数据,用灰色关联分析中的点关联系数求解隶属度得出评判矩阵,用范数灰关联度法确定因素集中各因素的权重,从而对其偿付能力进行模糊综合评判,得出各公司的偿付能力所属的类别.并对评语集中各评语赋予适当的权重,对所研究的8家财产保险公司依据其偿付能力的情况进行了排序. 相似文献
969.
Chih‐Cheng Lee Kun‐Ming Yeh Yun Chen 《Journal of polymer science. Part A, Polymer chemistry》2008,46(24):7960-7971
Two vinyl homopolymers poly(N‐(4‐(4‐(4‐vinylbenzyloxy)styryl)phenyl)‐N‐phenylbenzenamine) (PVST ) and poly(4‐vinyltriphenylamine) (PTPA ) containing pendant hole‐transporting triphenylamine and 4‐oxystyryltriphenylamine groups, respectively, were synthesized by radical polymerization and employed as hosts for tris(2‐phenylpyridine) iridium [Ir(ppy)3] phosphor. Structural influences of the hole‐transporting groups upon optoelectronic properties were investigated by photophysical, electrochemical, and electroluminescent methods. The polymers were readily soluble in common organic solvents and their weight‐average molecular weights (Mw) were 5.68 × 104 and 1.90 × 104, respectively. The emission spectra (both photoluminescence, PL and electroluminescent, EL) of the blends [PTPA with 4 wt % Ir(ppy)3] showed dominant green emission (517 nm) attributed to Ir(ppy)3 due to efficient energy transfer from PTPA to Ir(ppy)3. The HOMO levels of PVST and PTPA, estimated from onset oxidation potentials in their cyclic voltammograms, were ?5.14 and ?5.36 eV, which are much higher than ?5.8 eV of the conventional poly(9‐vinylcarbazole) (PVK) host owing to high hole‐affinity of the triphenylamine groups. The optoelectronic performances of phosphorescent EL devices, using PVST and PTPA as hosts and Ir(ppy)3 as dopant (indium tin oxide, ITO/poly(3,4‐ethylenedioxythiophene): poly(styrene sulfonate) (PEDOT:PSS)/PVST or PTPA:Ir(ppy)3(4 wt %):PBD(40 wt %)/BCP/Ca/Al), were investigated. The maximum luminance and luminance efficiency of the PTPA device were 9220 cd/m2 and 6.1 cd/A, respectively, which were significantly improved relative to those of PVK and PVST. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 7960–7971, 2008 相似文献
970.
In this article, electrochemistry of mitochondria is achieved. Cyclic voltammograms of freshly prepared mitochondria were obtained by immobilizing mitochondria together with glutaraldehyde and bovine serum albumin on the surface of a pyrolytic graphite electrode. Two pairs of redox peaks could be observed which were ascribed to the electron transfer reactions of cytochrome c and FAD/FADH2. Study of submitochondrial particles was also conducted, which could confirm the results of the study of the entire mitochondria. The redox wave of NADH could be obtained due to the destruction of the membrane of mitochondria. We have also checked the function of succinate in mitochondria by employing the electrochemical method. This work is not only the first to be able to obtain the direct electrochemistry of mitochondria, but is also beneficial to the further understanding of the structure and function of mitochondria in vitro. 相似文献