Abstracts of papers for

Previous issue vol. 44, no. 3 (2003)

vol. 44, no. 4 (2003)

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Contents of issue 4, vol. 44

1. S. K. Manna, S. Ghosh, S. C. Mandal: Torsional oscillation of rigid disk in an infinite cylinder
2. Z. Dżygadło, I. Nowotarski, A. Olejnik: Vibrations and stability of a biself-excited surface structure in supersonic flow subjected to a follower force
3. M. Bellenoue A. Cenian, T. Kageyama, S. A. Labuda, C. Leys: Electrical probe measurements of the gas velocity ahead of a combustion front and the burning velocity in propane/air mixtures
4. K. Pawlik, J. J. Wysłocki, O. I. Bodak, A. Przybył, I. Wnuk: Crystalline structure and magnetic properties of the Nd_12.5-x Fe_87.5 Zr_xalloys (x-2, 4, 6, 8, 10)
5. A. Szczepański: Non-classical properties of quantum information transfer: proposed experiments

S. K. Manna, S. Ghosh, S. C. Mandal: Torsional oscillation of rigid disk in an infinite cylinder

In this paper torsional oscillation of rigid disk in an infinite cylinder has been analyzed. The problem is reduced to solve the Fredholm integral equation of second kind by applying Hankel and Fourier transforms. Stress intensity factor at the edge of the strip has been derived and plotted to show the effect of cylinder width on stress intensity factor.

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Z. Dżygadło, I. Nowotarski, A. Olejnik: Vibrations and stability of a biself-excited surface structure in supersonic flow subjected to a follower force

A surface structure in supersonic flow having a deformable support and subjected to a follower compressing force, which preserves its direction tangential to the deformed surface, is a biself-excited system enclosing two independent physical factors being the reason of self-excited vibrations.

In the paper, a study of vibrations and stability of such a structure is presented using the example of a rectangular plate in one-side supersonic flow subjected to a follower force. The plate is considered under the assumption that the conditions of rigid support are satisfied at the plate edges parallel to the unperturbed flow direction. One of the remaining edges is clamped, while the second one has a deformable support. For comparison, the results of analysis in the case of a plate of finite length and infinite width are also presented.

A number of numerical calculations have been performed. The analysis indicates a variety of phenomena resulting from simultaneous action of the two independent factors decisive for self-excitation of the structure under consideration.

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M. Bellenoue A. Cenian, T. Kageyama, S. A. Labuda, C. Leys: Electrical probe measurements of the gas velocity ahead of a combustion front and the burning velocity in propane/air mixtures

A simple method, which enables determination of the laminar burning velocity and the unburned gas velocity ahead of the combustion front in a closed vessel, is presented in the paper. The method is based on electrical probe and Schlieren techniques. There is a good agreement between presented data and other works for all considered equivalence ratios of propane/air mixture. The dependence of unburned gas velocity on flame radius agrees well with the data received using LDV method. The obtained results demonstrate that some difficulties may appear when combustion front of non-spherical shape is considered.

Contents

K. Pawlik, J. J. Wysłocki, O. I. Bodak, A. Przybył, I. Wnuk: Crystalline structure and magnetic properties of the Nd_12.5-x Fe_87.5 Zr_x alloys (x-2, 4, 6, 8, 10)

The effect of Zr contents on the phase composition and magnetic properties of the Nd-Fe-Zr alloys was studied. In order to determine the phase composition, the X-ray diffraction was applied. It was stated that the following phases form the Nd-Fe-Zr alloy: Nd₂Fe₁₇, Fe₃Zr and α-Fe. Using optical microscope and electron scanning microscope, the microstructure observations were performed. Additionally, a linear analysis of the distribution of elements concentration was carried out. Furthermore, magnetocrystalline anisotropy constants K₁ and K₂ were determined applying Fourier analysis of the magnetic torque curves L(Θ) and Curie temperatures T_C using Farady's magnetic balance.

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A. Szczepański: Non-classical properties of quantum information transfer: proposed experiments

An experiment is proposed to test the feasibility of useful, classically complete information transfer between distant subsystems by means of the quantum channel alone. A second version of this experiment is proposed as a "gedanken" example of non-commutation of quantum measurements in spatially disjoint correlated subsystems.

Contents