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331.
Thetheoryofharmonicmapsintoacompactnonpositivelycurvedtargetiswell-developed.TheexistenceofsuchaharmonicmappinginanygivenhomotopyclassisestablishedbyEellsandSampson[1]in1964,andlater,in1967,Hartman[2]gaveaproofoftheuniqueness.Thispaperisdevotedtoanapplicationo… 相似文献
332.
In this paper,attention is focused on the intensity moments of the Hermite-Cosh-Gaussian (HChG) laser beams from the zero-order to the fourth-order.The frequently used parameters such as the power in bucket (PIB),the beam width,the curvature radius,the far field divergence,the M2-factor,the Rayleigh length and the kurtosis are calculated in terms of the intensity moments.Figures show the influence of the mode index and the decentered parameter,which are the critical parameters of the HChG beams.Moreover,the center of the gravity of the radiation field and the symmetry are discussed along with the propagation axis.Finally,the power fraction within the beam width defined by the second moments is illustrated with numerical method. 相似文献
333.
(Pb0.5Ba0.5)ZrO3 (PBZ) and 1 mol% Mn-doped (Pb0.5Ba0.5)ZrO3 (Mn-PBZ) sol were successfully fabricated, and corresponding thin films were deposited on Pt(1 1 1)/TiO2/SiO2/Si(1 0 0) substrates by spin-coating method. Effects of Mn doping on the microstructure and electrical properties of PBZ thin films were investigated systemically. X-ray diffraction patterns showed that both films had a polycrystalline perovskite structure, and that the degree of (1 1 1) orientation were increased by Mn doping. Dielectric measurements illustrated that Mn-doped PBZ thin films not only had a larger dielectric constant, but also possessed a smaller dielectric loss. Accordingly, the tunability and the figure of merit of PBZ films were improved by Mn doping. 相似文献
334.
In this paper, we fabricate a pure-shear mode film bulk acoustic resonator based on c-axis oriented ZnO film. The resonator is consisted of an in-plane electrode, a highly c-axis oriented ZnO film and a SiO2/W Bragg reflector. The shear mode wave is excited by the lateral electric field. The resonator works in a pure-shear mode with the resonance frequency near 1.5 GHz and the Q-factor of 479 in air. There is no obvious longitudinal mode resonance in the frequency response, which can be explained that the electric field component normal to the surface is very weak and the Bragg reflector has the effective frequency selectivity for the shear mode. Importantly for sensors, the immersion into de-ionized water and glycerol liquid still allows for a Q-factor up to 335 and 220, respectively. This resonator shows the potential as mass loading sensors for biochemical application. 相似文献
335.
The ground state properties of Cd, Sn and Te isotopes are investigated in the framework of the Skyrme-Hartree-Fock theory using the normal force parameters SKI2 plus density-dependent pairing correlations and new force parameters SKI4 which has a generalized spin-orbit term [P. G. Reinhard and H. Flocard, Nucl. Phys. A 584 (1995) 467]. The theoretical results agree well with experimental data of binding energies and matter root-mean-square radii of charge distributions. Both parameter sets are also successful in reproducing the experimental law of isotope shifts in Cd and Sn elements. The behavior of isotope shifts in Te elements is predicted. We have made detailed comparison and discussion on the numerical results and given an explanation for the cause of above success. 相似文献
336.
This paper is concerned with the limit relations from the Euler equations of one‐dimensional compressible fluid flow and the magnetohydrodynamics equations to the simplified transport equations, where the δ‐shock waves occur in their Riemann solutions of the latter two equations. The objective is to prove that the Riemann solutions of the perturbed equations coming from the one‐dimensional simplified Euler equations and the magnetohydrodynamics equations converge to the corresponding Riemann solutions of the simplified transport equations as the perturbation parameterx ε tends to zero. Furthermore, the result can also be generalized to more general situations. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
337.
Ruohu Zhang Zhuyuan Wang Chunyuan Song Jing Yang Yiping Cui 《Journal of fluorescence》2013,23(3):551-559
A straightforward immunoassay based on surface enhanced fluorescence (SEF) has been demonstrated using a fluorescent immune substrate and antibody functionalized-silver nanoparticles. Unlike the conventional SEF-based immunoassay, which usually uses the dye-labeled antibodies and the metallic nanostructured-substrates, the presented immune system does not need the antibodies to be labeled with dye molecules. Thus, this immunoassay can be easily applied to the detection of a wide range of target antigens, which is of great importance for its practical application. The experimental results show that this immunoassay has a good specificity as well as the capacity of quantitative detection. Basically, the surface density of the immuno-adsorbed silver nanoparticles increases with the increased amount of target antigens, resulting in a fluorescence enhancement up to around 7 fold. The dose-responsive performance of the immunoassay has been investigated and the limit of detection (LOD) is 1 ng/mL. Due to its simple preparation method and the wide range of detectable antigens, this presented immunoassay is expected to be helpful for extending the SEF-based application. 相似文献
338.
Xiangdong Zhang Peiyi Shen Chengke Wu Zhensen Wu 《International Journal of Infrared and Millimeter Waves》1998,19(12):1735-1743
Sea surfaces should be considered as randomly rough surfaces at the infrared(IR) and optical bands. The geometric model of sea surfaces has been obtained by using image processing. Based on the electromagnetic scattering theory, the Laser Radar Cross Section(LRCS) for the sea surfaces is analyzed at IR band and the scattering properties of the sea surfaces have been gotten. 相似文献
339.
Sonoluminescent tomography of strongly scattering media 总被引:1,自引:0,他引:1
A novel optical imaging technique called sonoluminescent tomography was developed for cross-sectional imaging of strongly scattering media noninvasively. Sonoluminescence, which was generated internally in the medium by cw ultrasound, was used to produce a two-dimensional image of an object embedded in a scattering medium by means of raster scanning the medium. The image had a high contrast and good spatial resolution. The spatial resolution was limited by the focal-spot size of the ultrasound, and one could improve the resolution by tightening the focus. This inexpensive imaging technique has potential applications in medicine and other fields related to scattering media. 相似文献
340.
The existence of solutions to systems is a natural premise to carry our study about controllability. Under the basic and readily verified conditions to guarantee the existence of the solutions to a system, in this paper, we prove the relative controllability (approximate controllability ) of the stochastic differential systems with delay in control. Sufficient conditions are given firstly for the relative controllability and relative approximate controllability in finite dimensional spaces, and these results are then generalized to infinite-dimensional Hilbert spaces. Finally, examples are given to illustrate the effectiveness of the proposed methods. 相似文献