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91.
In this paper, we numerically study the effect of electrical autaptic and synaptic delays on synchronization transitions induced by each other in Newman–Watts Hodgkin–Huxley neuronal networks. It is found that the synchronization transitions induced by synaptic delay vary with varying autaptic delay and become strongest when autaptic delay is optimal. Similarly, the synchronization transitions induced by autaptic delay vary with varying synaptic delay and become strongest at optimal synaptic delay. Also, there is optimal coupling strength by which the synchronization transitions induced by either synaptic or autaptic delay become strongest. These results show that electrical autaptic and synaptic delays can enhance synchronization transitions induced by each other in the neuronal networks. This implies that electrical autaptic and synaptic delays can cooperate with each other and more efficiently regulate the synchrony state of the neuronal networks. These findings could find potential implications for the information transmission in neural systems. 相似文献
92.
The nonlinear quantum vibrational energy spectra of amide-I in the molecular crystals acetanilide are calculated by using the discrete nonlinear Schr?dinger equation appropriate to this kind of crystals.The numerical results obtained by this method are in good agreement with the experimental values. Meanwhile, the energy levels at high excited states have also been obtained for the acetanilide, which is helpful in researching the Raman scattering and infrared absorption properties of the this kind of crystals. 相似文献
93.
X.-F. Pang 《The European Physical Journal B - Condensed Matter and Complex Systems》1999,10(3):415-428
The influence of a soliton on the properties of the M?ssbauer effect resulting from the gamma-active nuclei situated at lattice
sites in quasi-one-dimensional anharmonically organic molecular chains, in which the active nuclei emit gamma-photons, has
been theoretically studied by a quantum vibrational model. An expression for the gamma-radiated M?ssbauer transition probability
as a function of the temperature and non-linear interaction has been obtained. Finally we give some new properties of this
effect from numerical calculation in such a case, which present a way to experimentally confirm the soliton existence in molecular
crystals.
Received 9 April 1998 and Received in final form 11 December 1998 相似文献
94.
Biao Deng Jie Liang Luchao Yue Tingshuai Li Qian Liu Yang Liu Shuyan Gao Abdulmohsen Ali Alshehri Khalid Ahmed Alzahrani Yonglan Luo Xuping Sun 《中国化学快报》2022,33(2):890-892
Developing non-noble-metal oxygen evolution reaction(OER) electrocatalysts with high performance is critical to electrocatalytic water splitting. In this work, we fabricated Co Fe-layered double hydroxide(LDH) nanowire arrays on graphite felt(Co Fe-LDH/GF) via a hydrothermal method. The Co Fe-LDH/GF, as a robust integrated 3 D OER anode, exhibits excellent catalytic activity with the need of low overpotential of 252 and 285 m V to drive current densities of 10 and 100 m A/cm2 in 1.0 mol/L KOH, r... 相似文献
95.
96.
《Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy》1992,48(4):563-567
The adsorption behavior of p-aminobenzoic acid (PABA) molecules on a silver-coated alumina surface-enhanced Raman scattering (SERS) substrate was investigated. For spotted PABA and PABA in non-polar solvents, the PABA molecule is adsorbed flat on the surface of the SERS substrate. In this orientation, the benzene ring is π-bonded to the substrate, and the molecule is further anchored to the substrate by the binding of the lone pairs of NH2 and COO− groups onto the metal surface. On the other hand, the adsorption behavior of PABA in a polar solvent is greatly influenced by the hydrogen bonding of the amine group with the polar solvent. In this orientation, the molecule is preferentially adsorbed through the COO± and assumes a non-flat orientation on the metal surface. 相似文献
97.
98.
《Superlattices and Microstructures》1994,15(4):405-407
We have theoretically investigated the valence-band discontinuity (ΔEv) at the (100) GaAs/AlAs interface with the InAs strained insertion-layer. The theoretical calculation is carried out by the self-consistent tight-binding method with the sp3s* basis in the (GaAs)5/(InAs)1/(AlAs)5/(InAs)1 [100] superlattice. ΔEv at the GaAs/InAs(1ML)/AlAs interface is calculated to be 0.50 eV, which is practically equal to ΔEv = 0.51 eV at the GaAs/AlAs interface with no InAs layers. The insertion of the InAs monolayer changes the detail of valence charge density at the GaAs/AlAs interface but does not change ΔEv. The result of calculation is in consistent with our experimental measurement by using the x-ray photoelectron spectroscopy. 相似文献
99.
In most studies fat emulsion had been administered by enteral route. Recently a parenteral soybean-oil emulsion has been developed. In this study we assessed the effects of a parenteral soybean-oil emulsion (Intralipos((R))) and citric acid on blood rheology and erythrocyte morphology in vitro. Porcine blood was incubated in vitro with increasing concentrations of fat emulsion Intralipos((R)) and citric acid at 37 degrees C for 1h. Viscosity of plasma and whole blood was measured using a FASCO-2050 digital viscometer. Red blood cell morphology was examined by light microscopy. The viscosity of whole blood represented an ascending dose-dependence for different Intralipos((R)) concentrations at high shear rate of 90 and 225s(-1), however, it decreased with citric acid concentrations. On the other hand, the whole blood viscosity also declined with citric acid concentrations in presence of 30% Intralipos((R)) (v/v), and there is a minimal viscosity at 0.67% citric acid (v/v). There are some thorns on the blood membrane at 40% Intralipos((R)) as compared with control (no Intralipos((R)) addition), which indicates the Intralipos((R)) compound may affect blood cell membranes, and resulted in whole blood viscosity increase. We concluded that the intravenous soybean-oil preparation Intralipos((R)) interacts with the erythrocyte membrane, and citric acid could alleviate the whole blood viscosity. 相似文献
100.
利用电子顺磁共振(EPR)谱和透射电子显微镜(TEM)研究了YSZ单晶的辐照效应。200 keV的Xe和400 keV的Cs离子注入[111]取向的YSZ单晶中,注量均为5×1016 cm-2。EPR结果表明辐照产生了共振吸收位置g‖=1.989 和 g⊥=1.869、对称轴为[111]的六配位Zr3+顺磁缺陷。Cs辐照产生了比Xe 离子辐照多约150倍的六配位Zr3+顺磁缺陷。两种样品的剖面电子显微分析表明没有发现非晶化转变,但是Cs离子辐照的样品在损伤集中区域产生了密度较高的缺陷。因此,EPR谱和电子显微观察均说明在相同离位损伤(约160 dpa)的情况下,Cs离子辐照比Xe 离子辐照产生了更多的缺陷。造成这一现象的原因是Cs离子是化学活性的而Xe 离子却是惰性的。 相似文献