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  • A new type of vortex-free flows of helium II in a rotating cylinder

    Within the framework of the two-fluid Landau theory, flows into helium II inside a rotating cylinder are investigated. Special attention is paid to the analysis of excitation by centrifugal forces of counter-current (by super-fluid and normal components) flows. In the approximation of incompressible fluid, an analytical solution of the equations of motion, vortex-free for both components is obtained. The tangential velocities for it are the same as those of a rotating solid body, with the normal and superfluid components moving in opposite directions, with different angular velocities. It's resulting vorticity is compensated by a spiraled counter-current radical movements. Such solution has no axial symmetry and has a tangential gap along the radius. Despite its instability, it is of some interest. First, it can be corrected by stabilizing deformations. In addition, it shows the paths of loss of stability of high-symmetric States. In particular, in our opinion, this type of disturbance are intermediate flow from Landau (superfluid component is at rest) one to the rotation of the Feynman type (in the superfluid part of a system of vortices).

    Keywords: helium II, rotating cylinder, two-fluid theory, counter-current flows, centrifugal forces, vorticity compensation

  • Counter-current flows in rotating helium II

    The paper discusses the flow induced by centrifugal forces in helium II on the outside of the rotating cylinder. The analysis was carried out in the framework of Landau's two-fluid theory, in the approximation of a plane incompressible fluid. A two-parameter family of solutions of the equations of motion is revealed, in which the centrifugal forces for the normal component are fully compensated by counter-current (normal and super-fluid components) flows. According to preliminary estimates, the most stable of them is the flow, in which the pressure forces in the superconducting part are also compensated, The results show that in the analysis of helium II rotations it is necessary to take into account countercurrent instabilities.

    Keywords: helium II, rotating cylinder, two-fluid theory, counter-current flows, stability, centrifugal forces, pressure compensation

  • The radiation exposure estimation on biological tissue under gamma irradiation

    The paper presents the results of computational statistical experiment to estimate field radiation exposure on the soft tissue of the human body when external pressures are nondivergent narrow beam of gamma photon radiation. As an example, adopted the energy of a photon that enters 102 group energy axis constant laboratory ABBN. Given dose distribution in a cylinder diameter of 20 and a length of 10 centimeters. The method of statistical tests, known as Monte Carlo. Is used modify of the method with calculation the inverse functions. It is shown that the dose outside the beam ionization radiation load decreases by two orders, remains finite, that should be considered in therapeutic procedures, in which the total dose exceeds the lethal dose for a healthy bod

    Keywords: gamma therapy, model analysis, Monte Carlo, radiation dose

  • Technique of microinjection in axons of nerve cells, surrounded by dense glial sheath, using ultrasound vibration of microcapillary

    Intracellular microinjection - a method of direct introduction of cellular organelles and solutions of substances into living cells. The technique of microinjection into nerve cells by puncturing their processes - axons , which are often surrounded by a dense glial sheath, are described. To puncture the sheath a special injector transmitting microvibrations of ultrasonic frequency on the injection capillary was designed. The results of using the proposed microinjection technique for introducing fluorescent marker in large axons of model object - crayfish ventral nerve cord, to visualize the morphology of axons, were shown.

    Keywords: intracellular microinjection, neuron, axon, glial sheath, ultrasound vibration, piezoelectric transducer

  • Theoretical features of management of organizational conflict in modern management

    Article is devoted to aspects of management, aimed at investigating the nature of organizational conflict in order to identify the causes and possible management. Relevance of the topic emphasized by the fact that the study of conflict, its causes, and the methods and means of management emerged relatively recently and now, when the Russian economy is going through a stage of radical reform, this aspect of management is of interest for many researchers. Since the conflict in terms of joint activities of people are able to reduce labor productivity, it is necessary as soon as possible to anticipate. Particularly noteworthy are the management of organizational conflicts, as in the current economic development organization is a key participant in the economic relations and the conflicts that arise in this subject in need of early detection and effective management.

    Keywords: organizational conflict resolution, management, conflict management, the concept

  • Information about authors (№1, 2009)

    Information about authors of issue №1 (2009)

    Keywords: authors