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101.
The argument for non-existence of the B (3) field proposed by E. Comay is based on adding radians to the phase of a plane wave. This is trivially incorrect because B (3) is a vacuum component of a C conserving Yang-Mills gauge field theory.  相似文献   
102.
P. N. Pandita 《Pramana》1998,51(1-2):169-180
A review of the Higgs and neutralino sector of supersymmetric models is presented. This includes the upper limit on the mass of the lightest Higgs boson in the minimal supersymmetric standard model, as well as models based on the standard model gauge groupSU(2) L xU(l) Y with extended Higgs sectors. We then discuss the Higgs sector of left-right supersymmetric models, which conserveR-parity as a consequence of gauge invariance, and present a calculable upper bound on the mass of the lightest Higgs boson in these models. We also discuss the neutralino sector of general supersymmetric models based on the SM gauge group. We show that, as a consequence of gauge coupling unification, an upper bound on the mass of the lightest neutralino as a function of the gluino mass can be obtained.  相似文献   
103.
在无水乙醇溶液中分别合成了Eu^2+离子、Tb^3+离子与2,2‘-联吡啶、1,10-邻菲罗啉押种配合物,研究了配合物的荧光性质,由于Phen含有较大范围的共轭π键和较好的刚性平面,含Phen配合物的荧光强度均要比配合物的强;配合物的高分辨荧光光谱表明,Eu^3+离子在Eu(Dipy)2Cl3’2H2O和Eu(Phen)2Cl3.2H2O配合物中处于C1或C2或C5的对称性位置。  相似文献   
104.
It is shown that the effective gluon propagator in the global color symmetry model can be calculated in the instanton dilute liquid approximation. The calculated effective gluon propagator is consistent with the general command on the qualitative features of the gluon propagator, i.e., (i) the gluon propagator is significantly enhanced at small space-like k2, and (ii) for k2 > 1.5 GeV2 the perturbative results are quantitatively reliable.  相似文献   
105.
The phase structure of hadronic matter at high density relevant to the physics of compact stars and relativistic heavy-ion collisions is studied in a low-energy effective quark theory. The relevant phases that figure are (1) chiral condensation, (2) diquark color condensation (color superconductivity) and (3) induced Lorentz-symmetry breaking (“ISB”). For a reasonable strength for the effective four-Fermi current–current interaction implied by the low-energy effective quark theory for systems with a Fermi surface we find that the “ISB” phase sets in together with chiral symmetry restoration (with the vanishing quark condensate) at a moderate density while color superconductivity associated with scalar diquark condensation is pushed up to an asymptotic density. Consequently, color superconductivity seems rather unlikely in heavy-ion collisions although it may play a role in compact stars. Lack of confinement in the model makes the result of this analysis only qualitative but the hierarchy of the transitions we find seems to be quite robust.  相似文献   
106.
Incommensurate modulations in Ba2TiSi2O8, Sr2TiSi2O8, and Ba2TiGe2O8 are compared based on their corresponding electron diffraction patterns. The dependence of the modulations on chemical composition provides a suitable model system for the investigation of incommensurations in framework structures using high-resolution transmission electron microscopy (HRTEM). A widening of quantitative HRTEM utilising the concept of rigid units is proposed allowing for a determination of atomistic displacements responsible for the formation of incommensurately modulated structures.  相似文献   
107.
金咸宜 《大学物理》2022,41(1):11-14
从简化的地月系统力学模型出发,严格推导出地表物体动力学方程在转动坐标系下的表示形式,通过对称性的分析,得到引潮力,从而有助于加深对引潮力和潮汐成因的理解.  相似文献   
108.
Xi-zhong Liu 《中国物理 B》2022,31(5):50201-050201
A nonlocal Boussinesq equation is deduced from the local one by using consistent correlated bang method. To study various exact solutions of the nonlocal Boussinesq equation, it is converted into two local equations which contain the local Boussinesq equation. From the N-soliton solutions of the local Boussinesq equation, the N-soliton solutions of the nonlocal Boussinesq equation are obtained, among which the (N=2,3,4)-soliton solutions are analyzed with graphs. Some periodic and traveling solutions of the nonlocal Boussinesq equation are derived directly from the known solutions of the local Boussinesq equation. Symmetry reduction solutions of the nonlocal Boussinesq equation are also obtained by using the classical Lie symmetry method.  相似文献   
109.
Ya-Xiao Mo 《中国物理 B》2022,31(8):84301-084301
Large-scale topography, such as a seamount, substantially impacts low-frequency sound propagation in an ocean waveguide, limiting the application of low-frequency acoustic detecting techniques. A three-dimensional (3D) coupled-mode model is developed to calculate the acoustic field in an ocean waveguide with seamount topography and analyze the 3D effect. In this model, a correction is introduced in the bottom boundary, theoretically making the acoustic field satisfy the energy conservation. Furthermore, a large azimuth angle calculation range is obtained by using the operator theory and higher-order Padé approximation. Additionally, the model has advantages related to the coupling mode and parabolic equation theory. The couplings corresponding to the effects of range-dependent environment are fully considered, and the numerical implementation is kept feasible. After verifying the accuracy and reliability of the model, low-frequency sound propagation characteristics in the seamount environment are analyzed. The results indicate lateral variability in bathymetry can lead to out-of-plane effects such as the horizontal refraction phenomenon, while the coupling effect tends to restore the abnormal sound field and produces acoustic field diffraction behind the seamount. This model effectively considers the effects of the horizontal refraction and coupling, which are proportional to the scale of the seamount.  相似文献   
110.
The approximate solution of the magneto-hydrodynamic (MHD) boundary layer flow over a nonlinear stretching sheet is obtained by combining the Lie symmetry method with the homotopy perturbation method. The approximate solution is tabulated, plotted for the values of various parameters and compared with the known solutions. It is found that the approximate solution agrees very well with the known numerical solutions, showing the reliability and validity of the present work.  相似文献   
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