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151.
The authors consider the difference of Reidemeister traces and difference cochain of given two self-maps,and find out a relation involving these two invariants.As an application,an inductive formula of the Reidemeister traces for self-maps on a kind of CW-complex,including spherical manifolds is obtained. 相似文献
152.
Permutation polynomials over finite fields constitute an active research area and have applications in many areas of science and engineering. In this paper, four classes of monomial complete permutation polynomials and one class of trinomial complete permutation polynomials are presented, one of which confirms a conjecture proposed by Wu et al. (Sci China Math 58:2081–2094, 2015). Furthermore, we give two classes of permutation trinomial, and make some progress on a conjecture about the differential uniformity of power permutation polynomials proposed by Blondeau et al. (Int J Inf Coding Theory 1:149–170, 2010). 相似文献
153.
We construct a nonauto Darboux transformation for the extended noncommutative Kadomtsev–Petviashvili (ncKP) hierarchy and consequently derive its quasi-Wronskian solution. We also obtain the quasi-Wronskian solution of the ncKP equation with self-consistent sources (ncKPESCS) as a by-product. Finally, we use the direct verification method to prove the quasi-Wronskian solution of the ncKPESCS. 相似文献
154.
CONVERGENCE OF SIMPLIFIED AND STABILIZED MIXED ELEMENT FORMATS BASED ON BUBBLE FUNCTION FOR THE STOKES PROBLEM 总被引:1,自引:0,他引:1
IntroductionInordertogetridoftherestrictiontodiscreteBabuska_Brezzi’sconditionsinresearchesofmixedfiniteelement (MFE)methods,oneusuallyusesthestabilizedMFEmethodsformat[1] .Thereareanumberofstabilizedmethods (see ,e.g .,Refs.[1- 7]andthereferencestherein) ,whichh… 相似文献
155.
156.
This paper presents a volume integral equation method for an electromagnetic scattering problem for three-dimensional Maxwell's equations in the presence of a biperiodic, anisotropic, and possibly discontinuous dielectric scatterer. Such scattering problem can be reformulated as a strongly singular volume integral equation (i.e., integral operators that fail to be weakly singular). In this paper, we firstly prove that the strongly singular volume integral equation satisfies a Gårding-type estimate in standard Sobolev spaces. Secondly, we rigorously analyze a spectral Galerkin method for solving the scattering problem. This method relies on the periodization technique of Gennadi Vainikko that allows us to efficiently evaluate the periodized integral operators on trigonometric polynomials using the fast Fourier transform (FFT). The main advantage of the method is its simple implementation that avoids for instance the need to compute quasiperiodic Green's functions. We prove that the numerical solution of the spectral Galerkin method applied to the periodized integral equation converges quasioptimally to the solution of the scattering problem. Some numerical examples are provided for examining the performance of the method. 相似文献
157.
In this work, poly(diallyldimethylammonium chloride) (PDDA) protected Prussian blue/gold nanoparticles/ionic liquid functionalized reduced graphene oxide (IL-rGO-Au-PDDA-PB) nanocomposite was fabricated. The resulting nanocomposite exhibited high biocompatibility, conductivity and catalytic activity. To assess the performance of the nanocomposite, a sensitive sandwich-type immunosensor was constructed for detecting alpha-fetoprotein (AFP). Greatly enhanced sensitivity for this immunosensor was based on triple signal amplification strategies. Firstly, IL-rGO modified electrode was used as biosensor platform to capture a large amount of antibody due to its increased surface area, thus amplifying the detection response. Secondly, a large number of Au-PDDA-PB was conjugated on the surface of IL-rGO, which meant the enrichment of the signal and the more immobilization of label antibody. Finally, the catalytic reaction between H2O2 and the IL-rGO-Au-PDDA-PB nanocomposite further enhanced the signal response. The signals increased linearly with AFP concentrations in the range of 0.01–100 ng mL−1. The detection limit for AFP was 4.6 pg mL−1. The immunosensor showed high sensitivity, excellent selectivity and good stability. Moreover, the immunosensor was applied to the analysis of AFP in serum sample with satisfactory result. 相似文献
158.
采用密度泛函理论和含时密度泛函理论方法计算了2个吩噻嗪类染料及其吸附到TiO2上后分子的基态和激发态光物理性质与热力学参数.结果表明,电子给体的改变虽未明显改变染料的光谱性质(垂直跃迁能和振子强度),但可以改变分子的前线轨道能级,进而影响染料分子的激子结合能Eb及激发态电子注入到半导体TiO2中的驱动力△Gint的大小... 相似文献
159.
160.