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1.
In this paper, a block-by-block numerical method is constructed for the impulsive fractional ordinary differential equations (IFODEs). Firstly, the stability and convergence analysis of the scheme are established. Secondly, the numerical solution which converges to the exact solution with order $3+\gamma$ for $0<\gamma<1$ is proved, where $\gamma$ is the order of the fractional derivative. Finally, a series of numerical examples are carried out to verify the correctness of the theoretical analysis. 相似文献
2.
It is shown that every continuous action of a solvable group on a 1-arcwise connected continuum must have a fixed point or have a 2-periodic point. 相似文献
3.
§ 1 IntroductionThispaperisthesequelto[1 ,2 ].Cairnsetal.[1] introducedthenotionofachaoticgroupactionasageneralizationofchaoticdynamicalsystems(seedefinitionbelow) .Theyshowedthatthecircledoesnotadmitachaoticactionofanygroup ,andconstructedachaoticactionofG =Z×… 相似文献
4.
Li2FeSiO4/C composites were synthesized via a tartaric-acid-assisted sol–gel method with ethanol and ethylene glycol (EG) as mixed solvents. Effects of solvent composition on the physical properties and electrochemical performances of Li2FeSiO4/C were studied. The materials were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The electrochemical performances of Li2FeSiO4/C were evaluated by galvanostatic charge–discharge and electrochemical impedance spectra (EIS) measurements. The results show that the addition of EG to ethanol solvent during preparation has a positive effect on the electrochemical performance of Li2FeSiO4/C. The sample synthesized using EG–ethanol with the volume ratio of 2:7 has the best electrochemical performance. It delivers an initial discharge capacity of 105 mAh g?1 at C/16. AC impendence investigation shows that Li2FeSiO4/C synthesized using the optimal EG/ethanol volume ratio has lower resistance of electrode/electrolyte interface and higher lithium-ion diffusion coefficient than that synthesized using ethanol as solvent. 相似文献
5.
We consider the normalized Ricci flow ? t g = (ρ ? R)g with initial condition a complete metric g 0 on an open surface M where M is conformal to a punctured compact Riemann surface and g 0 has ends which are asymptotic to hyperbolic cusps. We prove that when χ(M) < 0 and ρ < 0, the flow g(t) converges exponentially to the unique complete metric of constant Gauss curvature ρ/2 in the conformal class. 相似文献
6.
Xiaowan Zhang Yixin Yang Peige Qin Lizhen Han Wenli Zhu Shaofeng Duan Minghua Lu Zongwei Cai 《中国化学快报》2022,33(2):903-906
In this work,the nano-g-C3N4/Ui O-66-NH2composite was prepared by one-step solvothermal method.The as-prepared composite was characterized by scanning electron microscopy,Brunner-Emmet-Teller measurement,energy dispersive spectrometer,X-ray diffraction,and Fourier transform infrared spectroscopy.By using nano-g-C3N4/Ui O-66-NH2composite as sorbent,a dispersive solid-phase extraction coupled with high-performance liquid chromatogra... 相似文献
7.
Rong Zhang Lu Liu Jing Zhang Wenyang Wang Fei Ma Ruifeng Li Lizhen Gao 《Journal of Solid State Electrochemistry》2015,19(6):1695-1707
8.
In a capacitively coupled discharge with external electrodes, He, H_2, N_2 or Ar were used as plasmagas, polymerization of octafluorocyclobutane was carried out under different conditions by varyingdischarge power, pressure, plasma gas and plasma-gas/monomer ratio. Structure of polymerizedproducts was characterized by IR spectroscopy and ESCA measurement. It was found that therewere six elements in the products, i.e. C, F, Si, O, N and H. The probably existed groups in poly-mers wer investigated. By analyzing the resolved peaks of C_(1S) region in ESCA spectra, effect of thereaction conditions on degree of branching of the polymerized products and the relationship of thepolymer structure wth the mechanism of the competitive ablation and polymerization process werestudied. In addition, polymer deposition process occurring in glow discharge was discussed. 相似文献
9.
Yifen HU Pengyu GAO Zhen XU Chuan ZHANG Lizhen HUANG Yunting HU Yarui AN Yingying GU 《Turkish Journal of Chemistry》2021,45(1):248
Ni(II)/CSs were prepared using a simple two-step hydrothermal method. The morphology and composition of the catalysts were studied with scanning electron microscope, transmission electron microscope, and X-ray diffraction. Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy showed that the surface of the prepared carbon spheres was rich in hydroxyl groups, which was beneficial to remove CO intermediates, and therefore, improving the catalytic efficiency and the antipoisoning ability of the catalysts. The results of cyclic voltammetry and chronoamperometry showed that the electrocatalytic activity and stability of Ni(II)/CSs were higher than that of unloaded NiAc under alkaline environment. When the nickel content was 5 wt.%, the peak oxidation current density of methanol on Ni(II)/CSs electrocatalyst reached the maximum of 34.54 mA/cm2, which was about 1.8 times that of unloaded NiAc. These results indicate that Ni(II)/CSs has potential applications in the electrocatalytic oxidation of methanol. 相似文献
10.