Physics
A QUARTERLY JOURNAL
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vol. 46, no. 3 (2005)
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 vol. 46, no. 4 (2005) |
Contents of issue 3, vol. 46
- R. Brojewski, B. Jakubiak, J. Jasiński: Dynamics of a 2L-baroclinic model of the troposphere. Part 1: Thermal bifurcation and blocking
- A. Ducrot, V. Volpert: On the thermodiffusion equation for electrically charged matter
- M. Ku¼miński, H.K. Lachowicz, K.L. Garcia, A. Zhukov, M. Vįzquez: Influence of alternating circular magnetic field strength on magnetoimpedance of glass-coated micro-wire
- Y. Tasinkevych, E.J. Danicki: On electrostatics of finite planar system of strips applied in surface acoustic wave interdigital transducers
- A. Szczepański: Quantum information transfer without classical channel: a proposed polarization-entanglement test
- R. Brojewski, B. Jakubiak, J. Jasiński: Dynamics of a 2L-baroclinic model of the troposphere. Part 1: Thermal bifurcation and blocking
- The paper analyzes, from the point of view of the theory of smooth dynamic systems, a simple two-layer model of baroclinic atmosphere applied within the main Hadley cell of circulation. The dynamics of the model was investigated in conditions excluding orographic influence but including momentum forcing in the upper and lower layers of the troposphere and thermal interaction between the troposphere and the surface for various vertical differentiations of the zonal drift in two tropospheric layers. The obtained results contribute to a profound view onto the applicability of classical weather forecasting models based on the hydrodynamic attitude.
- A. Ducrot, V. Volpert: On the thermodiffusion equation for electrically charged matter
- A strong temperature dependence of the reaction rate can result, for an exothermic chemical reaction, in heat explosion. In this work we study numerically the influence of natural convection on heat explosion. The model consists of the reaction-diffusion equation coupled with the Navier-Stokes equations under the Boussinesq approximation. A new type of heat explosion, the oscillating heat explosion is found. Critical conditions of explosion and complex nonlinear dynamics of the reaction-diffusion-convection problem are studied.
- M. Ku¼miński, H.K. Lachowicz, K.L. Garcia, A. Zhukov, M. Vįzquez: Influence of alternating circular magnetic field strength on magnetoimpedance of glass-coated micro-wire
- The presented experiments on giant magnetoimpedance (GMI) effect were carried out using glass-coated amorphous micro-wire specimen of its diameter of 22.4μm and nominal composition of Co67Fe3.85Ni1.45Mo1.7Si14.5B11.5. The main purpose of these experiments was to demonstrate the influence of the AC-current intensity flowing along this specimen and generating circular alternating magnetic field, on the properties of the GMI-effect. To demonstrate this, the GMI-ratio was measured vs. axial DC-field at various intensities of the AC-current ranging from 0.3 up to 5mA, the range which corresponds to the intensity of the circular field of around 4.8-80A/m at the surface of the micro-wire. The obtained dependences showed that the maximum of the GMI-ratio occurs at the intermediate intensity of the circular field, around 24A/m (identified with the threshold field of the micro-wire specimen magnetized in the circumferential direction). This result was confirmed analyzing the dependences of the wire impedance plotted vs. the intensity of AC-current for different selected DC-field as a parameter. The results were interpreted considering the expected domain structure in the wire, in particular, that its surface layer was composed of the stripe domains magnetized circumferentially, alternately in opposite directions ("bamboo structure"). Such a structure is created by the magnetoelastic anisotropy. In order to make this explanation more reliable, the penetration depth of the skin-effect was calculated on the grounds of the classical model. Analysis of the AC-field dependence of the penetration depth additionally confirmed the presented interpretation. The main conclusion which can be drawn from the performed experiments is that, in order to achieve optimum parameters of the GMI from the view-point of application in sensors, AC-current intensity should appropriately be chosen.
- Y. Tasinkevych, E.J. Danicki: On electrostatics of finite planar system of strips applied in surface acoustic wave interdigital transducers
- Planar systems of strips placed on a piezoelectric body are exploited in interdigital transducers for generation, detection and reflection of surface waves. The spatial field distribution in the plane of strips exhibits square-root singularities at the strips edges. In effect, the evaluation of charge spatial spectrum by direct application of the Fourier transformation to the spatial charge distribution never yields satisfactory accuracy. This is due to the strong dependence of the spectrum on the distribution details over the entire system. A new method is proposed here for direct evaluation of the spatial spectrum; the spatial distribution is obtained from it by the inverse Fourier transformation for certain auxiliary purposes and final verification of numerical results. The solution is constructed as a linear combination of the template functions, evaluated in spectral domain and satisfying the electric boundary conditions on the strips. The same functions are applied in the solution of the complementary problem of strips embedded in a preexisting electric field, assumed to be spatially variable (harmonic). In this case the strip total charge is evaluated dependent on the preexisting ("incident") field, as well as the Bloch harmonics of the "scattered" field in a wide spectral domain. Particular attention is dedicated to the numerical problems arising in evaluation of the template functions and the final charge spectrum. The computed examples show typical computational errors and how they were corrected by improving the numerical procedures.
Brief Notes
- A. Szczepański: Quantum information transfer without classical channel: a proposed polarization-entanglement test
- A quantum information transfer protocol in bipartite systems consisting of biphotons from parametric down-conversion without classical channel is shown to be a readily feasible modification of performed correlation experiments.
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