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11.
Here it is shown that magnetic materials with either microscopic atomic or molecular moments or macroscopic nanoscopic moments, represented by macroscopic permeability, can be detected by the quantum spin Hall effect of light (QSHEL), showing “spin” displacements normal to the interface with greater richness than previously found for dielectric materials. Also, it is proven for isotropic left-handed materials (LHMs), which rely upon magnetic action, that they do not display altered QSHEL results compared to their right-handed material (RHM) cousins which do.  相似文献   
12.
A multi-species two-level atomic system, the simplest being a representative two species collection of atoms studied here, contained in either a gaseous host medium or as dopants in a solid state host medium, determines the macroscopic permittivity and permeability seen by a probe field. Electronic or optical state initialization prepares the diagonal density matrix. Multi-species design of the atomic system allows assignment of different constituent densities in relation to the electric or magnetic matrix elements, generating left-handed electrodynamics in some detuning regions of the probe field.  相似文献   
13.
The electrophoretic mobility behavior of well-characterized polystyrene latex particles, carrying one type of surface functional endgroups, has been studied as a function of pH. At low pH, the interaction of protons with the functional endgroups increased in the order: Hydroxyl > carboxyl > sulfate; at high pH the order of interaction was reversed; and at intermediate pH no interactions were observed. The particles of the polystyrene latexes in their different forms at the intermediate pH range, dispersed in deionized water, all exhibited the same mobility irrespective of the functional endgroup. The origin of charge in these systems is explained as being the result of either the preferential adsorption of hydroxyl ions or an electron - injection mechanism due to the overlap of local intrinsic molecular - ion states in polystyrene and water. At low concentrations of functional endgroups, the surface properties of the polystyrene latexes are largely dependent upon the hydrophobic nature of the surface.  相似文献   
14.
The vanadium redox flow battery has been intensively examined since the 1970s. What is missing is a connection between the current-overpotential Butler-Volmer equation, which provides an extremely helpful starting point for analytical and numerical studies, and microscopic quantum mechanical behavior at the atomic level. Such a connection will allow further advancements beyond the macroscopic, though very useful and insightful, modeling already done in the literature. Here we show rigorously the connection between the Butler-Volmer transfer coefficients, and the Marcus Gibbs free energy quantum mechanical parameters, and develop the equation directly in terms of the quantum mechanical parameters.  相似文献   
15.

Background  

The hematopoietic Granulocyte-Colony Stimulating Factor (G-CSF) plays a crucial role in controlling the number of neutrophil progenitor cells. Its function is mediated via the G-CSF receptor, which was recently found to be expressed also in the central nervous system. In addition, G-CSF provided neuroprotection in models of neuronal cell death. Here we used the retinal ganglion cell (RGC) axotomy model to compare effects of local and systemic application of neuroprotective molecules.  相似文献   
16.
The electron energy relaxation is investigated as a function of the “electron temperature” Te in the n-channel of a (100) surface silicon MOSFET device by inspecting the phenomenological energy relaxation time τε(Te). τε is determined theoretically and compared to experimental results in order to identify the energy relaxation mechanism(s) present at the interface. Two dimensional electron transport is assumed. Single activation temperature (θ) Rayleigh wave scattering and acoustic Rayleigh wave scattering are studied as possible energy loss processes. The effects of electric subbanding near the surface are included. τε is calculated for Te ? 15 K in the electric quantum limit. We find that a single θ = 12.0 K Rayleigh phonon fits theory to experiment for a single electron inversion density (Ninv) case, but can not provide a fit simultaneously for more than one Ninv value. Theory and experiment disagree when Rayleigh wave acoustic scattering is assumed.  相似文献   
17.
Information is provided on the theory and design, fabrication, and experimental results for a phase shifter designed to operate in the millimeter wavelength region. The device was fabricated in a manner that makes it compatible with present GaAs monolithic microwave circuit technology. Continuously variable phase shift is obtained by varying the bias voltage from –5.0 to +0.65 V on a Schottky microstrip line. Experimental phase shift and loss data are provided for two different width (w) Schottky lines, w=1.5 and 7.3 m, for frequencies 2–18 GHz.  相似文献   
18.
19.
阐述了CVT(化学气相输运)法生长GaP的基本反应和输运速度,采用CVT法生长出了GaP多晶.设计了石英管的结构以制造出一个局部的低温区域,防止了GaP在管壁的生长.生长出的GaP多晶相对密度为98;,红外透过率达到30;,努普硬度为611kg/mm2.散射颗粒测试表明主要的光散射颗粒为多晶中存在的孔隙.  相似文献   
20.
Here we calculate the intrinsic quantum capacitance of RuO2 nanowires and RuO2/SiO2 nanocables (filled interiors, or nanotubes, which are empty), based upon available ab initio density of states values, and their conductances allowing determination of transmission coefficients. Comparisons are made to the intrinsic quantum capacitance of carbon nanotubes, and to RuO2 and RuO2/SiO2 Schottky and p-n junction capacitances. We find that the intrinsic quantum capacitance of RuO2 based nanostructures dominates over its junction capacitances by an order of magnitude or more, having important implications for energy and charge storage.  相似文献   
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