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981.
L. K. Seah U. S. Dinish S. K. Ong Z. X. Chao V. M. Murukeshan 《Optics & Laser Technology》2004,36(5):371-376
Imaging of latent fingerprints using time-resolved (TR) method offers a broader platform to eliminate the unwanted background emission. In this paper, a novel TR imaging technique is demonstrated and implemented, which facilitates the detection of latent fingerprints with nanosecond resolution. Simulated experiments were carried out with two overlapping fingerprints treated with two fluorescent powders having different lifetimes in nanosecond range. The dependence of the fluorescence emission intensity in nanosecond resolution of TR imaging is also revealed. 相似文献
982.
A detailed study of the generalized M2 factor of hard-edged diffracted beams based on the truncated second-order moments method, asymptotic analysis and self-convergent beam width approach is performed. The dependence of the generalized M2 factor on the parameters characterizing the spatial profile, and beam truncation, etc. is analyzed. 相似文献
983.
A mathematical model of laser beam treatment of double layer alloys (Ni/Fe, Al/Fe and Cr/Fe systems) describing the effect of laser beam on different physical and geometrical parameters of coated layer system has been adapted. The numerical solutions of the non-homogeneous heat-transport differential equation could estimate the temperature of the treated region.The suggested model allows investigation of the temperature distribution as a function of treated surface and laser parameters. The physical parameters of the treated materials were taken as functions of temperature due to the change in the temperature of the treated double layer materials. 相似文献
984.
Theory and experiment of spatially and temporally partially coherent speckle shearing interferometry
The theory and experiment of spatially and temporally partially coherent speckle shearing interferometry is reported in this rapid communication for the first time. The general requirements for the surface roughness and coherence area of a diffuse object surface in spatially and temporally partially coherent speckle shearing interferometry are discussed. An experimental verification is presented and the results of theory and experiment are in good agreement. 相似文献
985.
986.
S. B. Bushuk Yu. A. Kal'vinkovskaya A. N. Rubinov 《Journal of Applied Spectroscopy》2004,71(2):291-294
Capture of an ensemble of polymeric microspheres in a water suspension under the action of optical gradient forces in the field of interfering laser beams has been investigated for the case of two-, three-, and four-beam interference. The self-diffraction and diffraction of radiation on induced ordered spatial distribution of particles have been obtained. 相似文献
987.
On Covariant Phase Space and the Variational Bicomplex 总被引:1,自引:0,他引:1
Enrique G. Reyes 《International Journal of Theoretical Physics》2004,43(5):1267-1286
The notion of a phase space in classical mechanics is well known. The extension of this concept to field theory however, is a challenging endeavor, and over the years numerous proposals for such a generalization have appeared in the literature. In this paper We review a Hamiltonian formulation of Lagrangian field theory based on an extension to infinite dimensions of J.-M. Souriau's symplectic approach to mechanics. Following G. Zuckerman, we state our results in terms of the modern geometric theory of differential equations and the variational bicomplex. As an elementary example, we construct a phase space for the Monge–Ampere equation. 相似文献
988.
Employing positive-definiteness arguments we analyse Boson field states, which combine classical and quantum mechanical features (signal and noise), in a constructive manner. Mathematically, they constitute Bauer simplexes within the convex, weak-*-compact state space of the C*-Weyl algebra, defined by a presymplectic test function space (smooth one-Boson wave functions) and are affinely homeomorphic to a state space of a classical field. The regular elements are expressed in terms of weak distributions (probability premeasures) on the dual test function space. The Bauer simplex arising from the bare vacuum is shown to generalize the quantum optical photon field states with positive P-functions. 相似文献
989.
对以本征Si及重掺杂p型和n型Si作为中间层的Fe/Si多层膜的层间耦合进行研究,并通过退火,增大Fe,Si之间的扩散,分析界面扩散对层间耦合的影响. 实验结果表明,层状结构良好的制备态的多层膜,Fe,Si之间也存在一定程度的扩散,它是影响层间耦合的 主要因素,远远超过了半导体意义上的重掺杂,使不同种类的Si作为中间层的层间耦合基本 一致.进一步还发现,在一定范围内增大Fe,Si之间的扩散,即使多层膜的层状结构已经有了相当的退化,Fe/Si多层膜的反铁磁耦合强度基本保持不变.
关键词:
Fe/Si多层膜
层间耦合
界面扩散 相似文献
990.