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941.
我们曾报道了沉积在 Sn O2 导电玻璃基片上的 5 ,1 0 ,1 5 ,2 0 -四 -(4 -十六烷基吡啶基 )卟啉 [TC16 Py P(4 ) ]LB膜的光电性质 [1] .结果表明 ,电解质溶液中含有电子给体和受体时 ,由于超敏化作用 ,样品光电效应明显增强 .在研究其它 LB膜时 ,我们发现将两亲性卟啉分子 A与等物质的量憎水性化合物 B一起拉膜时 ,有可能得到一一对应的混合 LB膜[2 ] .如果 A和 B分别为电子给体和受体 (反之亦然 ) ,A和 B之间应有较强的相互作用 .将这种混合 LB膜沉积在基板上 ,可能表现出新的电子与光学性质 ,从而得到具有多种功能的新材料 .本文… 相似文献
942.
《Microelectronics Journal》2014,45(6):690-701
Recent studies have verified the efficiency of stochastic state point process filter (SSPPF) in coefficients tracking in the modeling of the mammalian nervous system. In this study, a hardware architecture of SSPPF is both designed and implemented on a field-programmable gate array (FPGA). It provides a time-efficient method to investigate the nonlinear neural dynamics through coefficients tracking of a generalized Laguerre–Volterra model describing the spike train transformations of different brain sub-regions. The proposed architecture is able to process matrices and vectors with arbitrary sizes. It is designed to be scalable in parallel degree and to provide different customizable levels of parallelism, by exploring the intrinsic parallelism of the FPGA. Multiple architectures with different degrees of parallelism are explored. This design maintains numerical precision and the proposed parallel architectures for coefficients estimation are also much more power efficient. 相似文献
943.
We have studied the atomic structure in the interior of discommensurate domains of the Cu/Ge(111) surface by using scanned-angle X-ray photoelectron diffraction (XPED). XPED patterns of Cu 2p3/2 intensity provided direct information on the local structure in the vicinity of photoelectron emitters. It has been found that a certain number of Cu atoms are embedded within the surface layer, so that the surface has some structural similarity with the discommensurate Cu/Si(111)-‘5×5’. 相似文献
944.
Giovanna Guidoboni Roland Glowinski Matteo Pasquali 《Journal of Computational and Applied Mathematics》2009,232(1):72-81
Free surface flows are pervasive in engineering and biomedical applications. In many interesting cases—particularly when small length scales are involved—surface forces (capillarity) dominate the flow dynamics. In these cases, computing the flow together with the shape of the surfaces, requires specialized solution techniques. This article investigates the capabilities of an operator splitting/finite elements method at handling accurately incompressible viscous flow with free surfaces at low capillary numbers. The test case of flow in the downstream section of a slot coater is used for three reasons: (1) it is an established benchmark; (2) it represents an idealized, yet industrially relevant flow; (3) high-fidelity results obtained with monolithic algorithms are available in literature. The flow and free surface shape attained with the new operator splitting scheme agree very satisfactorily with the results obtained with monolithic solvers. Because of its inherent computational simplicity, the new operator splitting scheme is attractive for large-scale simulations, three-dimensional flows, and flows of complex fluids. 相似文献
945.
SIMPLIFIED LATTICE REALIZAT ION OF FIR DIGITAL FILTERS 总被引:1,自引:0,他引:1
This paper suggests a simplified lattice structure for implementing FIR digital filters,which halvesthe hardware requirements of a conventional lattice realization.The conversion algorithms between directrealizations and the simplified lattice forms are given.Furthermore,the algorithms for linear phase FIR fil-ters are simplified.The principal results are illustrated by a practical example. 相似文献
946.
About some physical mechanisms of statistics of radiation-induced effects formation and non-linear cell response in low dose area 总被引:1,自引:0,他引:1
A new cascade-stochastic approach to solve the direct and inverse problems of radiation-induced effect statistics in track biodetectors is presented in this paper. The analysis of the experimental data has made it possible to establish a non-linear nature of the “dose–effect” dependence in low dose area. For the first time, a new determination of the relative biological efficiency and quality coefficient of ionizing radiation in area of low doses are proposed. 相似文献
947.
In this paper,a technique for designing 3-D separable-denominator state-spacedigital filters is developed. The design process is divided intotwo phases. First, the coefficient matrices related to stabilityare constructed for the filter to be stable by using alternatingvariable method. Next, the other matrices are obtained by solvinglinear equations. These phases are repeated until there is nosignificant change in the squared error function. 相似文献
948.
Henk J.A.M. Heijmans Batrice Pesquet-Popescu Gemma Piella 《Applied and Computational Harmonic Analysis》2005,18(3):252-281
In this paper, we propose a technique for building adaptive wavelets by means of an extension of the lifting scheme. Our scheme comprises an adaptive update lifting step and a fixed prediction lifting step. The adaptivity consists hereof that the system can choose between two different update filters, and that this choice is triggered by the local gradient of the original signal. If the gradient is large (in some seminorm sense) it chooses one filter, if it is small the other. We derive necessary and sufficient conditions for the invertibility of such an adaptive system for various scenarios. Furthermore, we present some examples to illustrate our theoretical results. 相似文献
949.
Summary The analytical roles of chromatographic variables (column length, etc.) can be soundly comprehended and compared in terms
of the precision (Φ) of measurements and efficiency (ϑ) of analysis which are described as Shannon information and information
flow, respectively. The φϑ plots of the optimization process and the information Φ transmitted by a single peak are useful
to understand the analytical structure of optimization. Variables treated here are mobile phase composition (X), column length
(L), mobile phase velocity rate (u), detection wavelength (λ) and plate number (N). 相似文献
950.
K.A. Schmidt M. Bergström G.B. Hagemann B. Herskind G. Sletten P.G. Varmette J. Domscheit H. Hübel S.W. Ødegård S. Frattini A. Bracco B. Million M.P. Carpenter R.V.F. Janssens T.L. Khoo T. Lauritsen C.J. Lister S. Siem I. Wiedenhöver D.J. Hartley L.L. Riedinger A. Maj W.C. Ma R. Terry 《The European Physical Journal A - Hadrons and Nuclei》2001,12(1):15-28
High-spin properties of the nucleus 169Hf have been studied through the fusion evaporation reaction 96Zr(76Ge,3n)169Hf at a beam energy of 310 MeV. The known rotational bands have been extended considerably and 6 new bands have been established,
four of which form coupled bands with pronounced M1 connections. Quasiparticle assignments are suggested for the new band structures, and it appears that coupling to vibrational
degrees of freedom plays a role. Both coupled bands involve the excitation of quasiprotons. In the region of highest spin,
a large alignment gain is interpreted in terms of a mixed crossing where an h
9/2 and an h
11/2 quasiproton provide the two signatures of the aligning configuration.
Received: 23 March 2001 / Accepted: 20 September 2001 相似文献