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951.
Mass difference oft-flavored hadrons is calculated using bag model modified for considering heavy quarks inside the bag. Both electric and magnetic contributions to mass differences are evaluated without the assumption of degenerate intermediate state. Mass differences between up and down quarks inside the bag is taken to be a constant in the absence of a dynamical calculations for the same.  相似文献   
952.
Summary A model of thermal laser ablation of soft tissues is developed taking into consideration two mechanisms: evaporation and liquid moving, due to vapour pressure gradient. Usually a soft tissue is modelled as a single-component material with thermal and optical properties very similar to those of water. We examined the non-stable kinetics of the evaporation process, for short-pulse infrared laser ablation of soft tissues, and we also calculated the average liquid velocity and the ablation rates under vapour pressure gradient. The theoretical results are in good agreement with previous reported experimental data on gelatin and polyacrylamide tissue phantoms The authors of this paper have agreed to not receive the proofs for correction  相似文献   
953.
Application of the Galerkin methods to the numerical analysis of the integro-differential electric field equation is justified. The convergence of the Galerkin methods is established for a class of equations with nonelliptic operators comprising the electric field equation. Theorems concerning the approximation of the elements belonging to a special Sobolev space by the basis Rao-Wilton-Glisson functions are proved. The rate of convergence is estimated.  相似文献   
954.
从电磁铁的工作原理分析入手,详细介绍了电磁选矿机的设计思路和方法,该方案比永磁式选矿机具有良好的性价比,可以大大提高铁粉的回收率,自动化程度高,并且在结构上具有创新性,是值得推广的一种设计方案。  相似文献   
955.
A recent article, claiming to identify an electromagnetic system with a field whose group velocity is faster than light, is disproved.  相似文献   
956.
何宜军  杨铨让 《光学学报》1992,12(10):921-924
利用电磁场的旋量体系方法对斜入射平面波的平面孔径的电磁衍射进行了分析.获得了任意入射情况下孔径的衍射强度公式,并以特例说明与前人的公式是一致的.  相似文献   
957.
Instantaneous measurement of field quadrature moments and entanglement   总被引:1,自引:0,他引:1  
We present a method of measuring expectation values of quadrature moments of a multimode field through two-level probe “homodyning”. Our approach is based on an integral transform formalism of measurable probe observables, where analytically derived kernels unravel efficiently the required field information at zero interaction time, minimizing decoherence effects. The proposed scheme is suitable for fields that, while inaccessible to a direct measurement, enjoy one and two-photon Jaynes-Cummings interactions with a two-level probe, like spin, phonon, or cavity fields. Available data from previous experiments are used to confirm our predictions.  相似文献   
958.
This paper is described for T-matrix analysis of the electromagnetic wave diffraction from a Fourier grating that the boundary value problem is treated by applying the extended boundary condition. The rigorous form of the expression of matrix elements is presented in the term of Bessel functions of the first kind. The error of power conservation versus the truncated number has been examined for mode number. Diffraction efficiencies versus groove depth and wavelength for a second or third harmonic wave of Fourier grating have been discussed. Numerical results are in good agreement with those obtained from other method and experimental values. Reasonable numerical results are presented for a groove depth per period of the Fourier grating less than 0.25.  相似文献   
959.
The classical non-relativistic problem of the motion of a charged particle in an external central force field and a weak uniform magnetic field is revisited to show that the motion of the kinetic angular momentumL = r × p of the particle, in the so-called Larmor approximation, is not a simple precession but is actually a composite motion involving precession as well as a high frequency nutation. The precession-nutation motion ofL is discussed in the Larmor approximation when the Larmor-frame-orbit of the charged particle is an ellipse (or a circle) for the case of the two central forces namely the Coulomb and the Hooke-law-force, which are the only two central forces known to permit closed orbits.  相似文献   
960.
It is shown that the Evans-Vigier modified electrodynamics is compatible with relativity theory.  相似文献   
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