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71.
复局部β-凸空间l~β与L~β[0,1]的共轭锥的次表示定理   总被引:2,自引:0,他引:2  
王见勇 《数学学报》2005,48(6):1155-1166
本文研究复局部β-凸空间l~β与L~β[0,1](0<β<1)的共轭锥(l~β)_β~*与(L~β[0,1])_β~*的构造与表示问题,得到(l~β)_β~*(?)mM_β~+(T),(L~β[0,1])_β~*(?)L~∞M_β~+(I×T),称为(l~β)_β~*与(L~β[0,1])_β~*的次表示定理。  相似文献   
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73.
Crystalline LiFePO4 nanoplates were incorporated with 5 wt.% multi-walled carbon nanotubes (CNTs) via a facile low temperature polyol process, in one single step without any post heat treatment. The CNTs were embedded into the LiFePO4 particles to form a network to enhance the electrochemical performance of LiFePO4 electrode for lithium-ion battery applications. The structural and morphological characters of the LiFePO4–CNT composites were investigated by X-ray diffraction, Fourier Transform infrared spectroscopy, Raman spectroscopy, scanning electron microscopy and transmission electron microscopy. The electrochemical properties were analyzed by cyclic voltammetry, electrochemical impedance spectroscopy and charge/discharge tests. Primary results showed that well crystallized olivine-type structure without any impurity phases was developed, and the LiFePO4–CNT composites exhibited good electrochemical performance, with a reversible specific capacity of 155 mAh g−1 at the current rate of 10 mA g−1, and a capacity retention ratio close to 100% after 100 cycles.  相似文献   
74.
A simple electrostatic apparatus was devised to measure dischargeable electricity and bioelectric potentials produced by flies. The apparatus involved two insulated electrodes, ICW(−) and ICW(+), oppositely charged with equal voltages supplied by two voltage-generators. In the electric field, the flies became net positive by instantaneously discharging their electricity and were attracted to negative surface charges on ICW(−). The tail-lifting movement by the attracted insect was an action creating electric potentials that could cause discharge of ICW(−). The discharge transiently appeared in response to individual movements and was larger when the tail was lifted at higher angles.  相似文献   
75.
We investigate theoretically the electronic transport through a parallel-coupled double quantum dot (DQD) molecule attached to metallic electrodes, in which the spin-flip scattering on each quantum dot is considered. Special attention is paid to the effects of the intradot spin-flip processes on the linear conductance by using the equation of motion approach for Green’s functions. When a weak spin-flip scattering on each quantum dot is present, the single Fano peak splits into two Fano peaks, and the Breit–Wigner resonance may be suppressed slightly. When the spin-flip scattering strength on each quantum dot becomes strong, the linear conductance spectrum consists of two Breit–Wigner peaks and two Fano peaks due to the quantum interference effects. The positions and shapes of these resonant peaks can be controlled by using the magnetic flux through the quantum device.  相似文献   
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77.
Guohua Qian 《Journal of Algebra》2010,323(11):3134-3141
The results of this paper are as follows: for a finite group G, if all primitive irreducible characters are linear, or if all nonmonomial irreducible characters have the same degree, then G is solvable.  相似文献   
78.
This paper is concerned with the existence for impulsive semilinear differential equations with nonlocal conditions. Using the techniques of approximate solutions and fixed point, existence results are obtained, for mild solutions, when the impulsive functions are only continuous and the nonlocal item is Lipschitz in the space of piecewise continuous functions, is not Lipschitz and not compact, is continuous in the space of Bochner integrable functions, respectively.  相似文献   
79.
In this paper, we present a DI SIR epidemic model with two categories stochastic perturbations. The long time behavior of the two stochastic systems is studied. Mainly, we show how the solution goes around the infection-free equilibrium and the endemic equilibrium of deterministic system under different conditions.  相似文献   
80.
A new cadmium complex [Cd(C5H5N)CH2C(OH)(PO3)(PO3H)·3H2O]n((C5H4N)CH2C(OH)(PO3H2)2=1-hydroxy-2-(2-pyridyl)ethylidene-1,1-diphosphonate acid) has been synthesized under hydrothermal conditions. Single crystal structure determination reveals that the compound has a ladder-like chain structure in which the edge-shared {CdO6} octahedra are linked by {CPO3} tetrahedra through corner-sharing. The chains of {Cd(C5H5N)CH2C(OH)(PO3)(PO3H)}n are linked by inter-chain hydrogen bonds, forming a supramolecular layer. CCDC: 722396.  相似文献   
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