R e g u l a r p a p e r s

Theoretical and mathematical physics

Moscow University Physics Bulletin 2010. **65**. N 3. P. 159

The problem of the thermodynamic consistency of equations of state obtained by using distribution functions is considered. The effect of thermodynamic consistency of equations on the accuracy of their calculations is determined. It is shown that the velocity of convergence of the thermodynamically consistent perturbation theory series in the general case is determined by the behavior of the distribution functions in the total range of the coordinate changes. A new method for the full thermodynamic consistency of equations of state obtained on the basis of thermodynamics perturbation theory is proposed.

Show AbstractMoscow University Physics Bulletin 2010. **65**. N 3. P. 164

The movement of a magnetized particle in the equatorial plane of a magnetic dipole is investigated. Analysis and classification of trajectory types for such particles are made. It is shown that eight different trajectory types are possible, which depend on the particle’s energy and on the orientation of its magnetic dipole moment. This permits the use of an axial magnetic field to move a magnetized particle in any point of the magnetic equatorial plane.

Show AbstractMoscow University Physics Bulletin 2010. **65**. N 3. P. 170

Human radiation exposures from uranium via the skin or lungs during emergencies at nuclear plants are considered. The effective dose that can accumulate in humans and the dose coefficient of uranium are calculated. Models developed by the authors, which describe air pollution in a factory shop and uranium penetration through the skin are used. The effective doses accumulated in humans through the skin and via inhalation are compared. The effect of uranium on the skin is estimated and the skin layer most affected by radiation is determined.

Show AbstractOptics and spectroscopy. Laser physics

Moscow University Physics Bulletin 2010. **65**. N 3. P. 174

A new method of optical control of the output power of an ytterbium double-clad fiber laser is pro- posed. The method is based on the possibility of modulating the main channel gain coefficient inside an active element using the radiation of the competitive control channel. The advantage of this method consists in the fact that the main channel is modulated without inserting any controlling elements inside it. The static characteristics of the channel modulation are theoretically studied and the theoretical results are verified experimentally.

Show AbstractMoscow University Physics Bulletin 2010. **65**. N 3. P. 180

The role of harmonic and random external forces in a phenomenological nonlinear model of optical heartbeats is investigated. External forces trigger damped oscillations at the natural frequency of the system and higher harmonics. The numerical results are compared with experimental ones.

Show AbstractCondensed matter physics

Moscow University Physics Bulletin 2010. **65**. N 3. P. 184

This work discusses the formation of self-accommodation complexes of martensite crystals during transformations of distortion type and experimentally observed shape memory effects in unordered solid solutions. A method for the analysis of orientation relationships between the lattices of austenite and marten-site in terms of the possibility of formation of self-accommodation complexes is given.

Show AbstractMoscow University Physics Bulletin 2010. **65**. N 3. P. 189

We demonstrate the possibility of a unique reconstruction of the coordinate dependence of all dielectric permittivity tensor components of an absorbing one-dimensionally inhomogeneous plate with any symmetry (except for 1, 2, and m classes) and a negligibly small spatial dispersion. This reconstruction can be performed, the zone of the strong frequency dispersion of the medium inclusive, provided that the reflection and transmission coefficients for the $p$- and $s$-polarized plane monochromatic waves are known in a certain range of incidence angles.

Show AbstractAstronomy, astrophysics, and cosmology

Moscow University Physics Bulletin 2010. **65**. N 3. P. 195

This paper analyses the possibility of separating distinct groups of nuclei of primary cosmic rays with energies of ${10}^{15}$-${10}^{16}$ eV from the data on the spatial-angular distribution of Cherenkov light in extensive air showers. The paper shows that using an array of a few (3–4) telescopes with a moderately sized angular cell ∼0.5° placed at a distance ∼100 m from one another, one can achieve almost complete separation of the showers initiated by these nuclei (the Bayesian classification error is a few percentage points for the case of separating primary protons and nitrogen nuclei). The authors propose new parameters of the angular Cherenkov image that can greatly enhance the separability of the shower classes as compared to the approach based on the traditional parameters.

Show AbstractPhysics of Earth, atmosphere, and hydrosphere

Moscow University Physics Bulletin 2010. **65**. N 3. P. 203

In this work, a mathematical model of a springtime thermal bar is constructed. A closed system of Reynolds-type equations is used; it is constructed based on a nonlinear system of thermohydrodynamic equations with the use of a special method for extracting the large-scale structures in a turbulent medium. A numerical solution of this system in a water reservoir with an inclined bottom is obtained; the contribution introduced by the Coriolis force into thermodynamic processes in a water reservoir in the period of existence of a springtime thermal bar is demonstrated.

Show AbstractMoscow University Physics Bulletin 2010. **65**. N 3. P. 209

Paleomagnetic studies have revealed that natural ferrimagnetics, which are constituents of igneous rocks, can be magnetized antiparallel to the magnetizing field. This phenomenon is called self-reversal of magnetization. The question of the actual existence of inversions of the geomagnetic field is still under investigation. This paper considers the physics of the anomalous behavior of natural ferrimagnetic thermomagnetization (TM). The existence of thermomagnetization arising in natural ferrites against the direction of a magnetizing field is experimentally confirmed. It is shown that even after the demagnetization of a ferrimagnetic by alternating magnetic field a significant increase in residual magnetization can occur when it is heated in the absence of a magnetic field.

Show AbstractB r i e f r e p o r t s

Theoretical and mathematical physics

Moscow University Physics Bulletin 2010. **65**. N 3. P. 150

An example of the application of fractional integro-differentiation is presented. A method for interpreting the solution of a diffusion-wave equation was proposed in [1].

Show AbstractRadiophysics, electronics, acoustics

Moscow University Physics Bulletin 2010. **65**. N 3. P. 214

We examine various methods based on specific experimental results for finding the rate of propagation of a pulsed discharge over a water surface.

Show AbstractMoscow University Physics Bulletin 2010. **65**. N 3. P. 217

The logical state of the memory cells in a nondestructive microcontroller was determined and analyzed by atomic-force microscopy. An effective optimal recording procedure of the electric potential on the microchip surface was created.

Show AbstractMoscow University Physics Bulletin 2010. **65**. N 3. P. 220

We present the results of experimental investigations into the ignition and combustion of hydrocarbon films deposited on a water surface by a pulsed discharge propagating above the liquid in motionless air under atmospheric pressure.

Show AbstractOptics and spectroscopy. Laser physics

Moscow University Physics Bulletin 2010. **65**. N 3. P. 223

A circular Gaussian beam of monochromatic laser radiation is normally incident to the plane of a right-angle thin metal plate and diffracts at the edges of the plate angle. It is revealed that two main fragments of a composite diffracted wave with cylindrical wave fronts whose axes are mutually orthogonal occur and interfere with each other in the shadow region behind the plate. This is found from the characteristic interference pattern on a flat screen behind the plate. This interference pattern consists of intensive curvilinear, wedge-shaped bands that are located symmetrically in pairs with respect to the bisector of the direct central angle of the circular shadow sector.

Show AbstractBiophysics and medical physics

Moscow University Physics Bulletin 2010. **65**. N 3. P. 227

Phase and component segregation in lipid membranes was studied by means of mathematical modeling. The time dependence of phase segregation on the lateral diffusion coefficient was calculated. The phase and component segregations were also simulated by multiparticle Monte-Carlo methods, and the phase diagrams of the system were obtained.

Show AbstractMoscow University Physics Bulletin 2010. **65**. N 3. P. 230

A variant of mathematical model construction for the anaerobic metabolism of a purple nonsulfur bacterium based on a flux balance analysis is presented in this paper. The model includes all the central metabolic pathways of the bacterial cell, as well as pathways for biosynthesis of amino acids and bacteriochlorophyll. It is shown that the results of modeling of bacterial photoheterotrophic growth on acetate agree with experimental values for the known metabolite pathways, which shows that the constructed model adequately describes actual cellular processes.

Show AbstractPhysics of Earth, atmosphere, and hydrosphere

Moscow University Physics Bulletin 2010. **65**. N 3. P. 234

This paper presents data on relativistic electron fluxes (1.5–3 MeV) measured at altitudes of 360–500 km onboard the CORONAS-F satellite. The monthly average fluxes of these particles in the Earth’s outer radiation belt are shown to greatly increase from August 2001 to September 2003. The monthly average fluxes of relativistic electrons in the Earth’s outer radiation belt in the period from August 2001 to July 2004 are also found to be strongly correlated with the monthly average velocities of the solar wind and values of the Kp-index, with this correlation breaking down after July 2004. This paper discusses the possible reasons for the discovered patterns.

Show Abstract