[en] Parametric striction instability of helicon of a finite amplitude (whistler) in collisional plasma has been considered. Cases of propagation of low-frequency density perturbation both along external magnetic field and at an angle to it when propagating a magnetoacoustic wave have been studied. Determined are intervals of wave numbers, where helicon instability is possible, as well as threshold values of collision frequencies above which instability is impossible. It is established that when propagating low-frequency perturbation along the external magnetic field the helicon instability develops especially rapidly. For this case a nonlinear problem related to decay of pumping helicon to two satellites and low-frequency perturbation has been numerically solved

[en] Heat transfer is studied theoretically for an electrically conducting liquid thin film flowing over a corrugated surface

[en] In connection with the experiments on sounding magnetosphere from the Earth surface by very low-irequency signals and investigations of regularities of these waves propagation in magnetosphere thermal modulation instability of whistlers is analytically investigated. The expressions are obtained for instability increment and interval of wave numbers of low-frequency plasma density disturbance at which instability is developed is determined. Threshold frequency values of electron collisions and whistler amplitude are determined. It follows from magnetospheric plasma estimations that the thermal helicon modulation can develop in it at real amplitude values of whistler (H⁰ approximately 10^-₇ epsilon), the wave length of low-frequency disturbance is of the order or more than the electron free path length in plasma. By numerical methods the problem on whistler decay into two satellites and the low-irequency disturbance are investigated

[en] The critical Reynolds number is computed for the laminar flow of an incompressible viscous liquid metal thin film

[en] The laminar flow of a molten-metal film over a metal surface is studied in the noninductive approximation

[en] The behaviour of droplets and liquid lithium film which is supposed to be used in a divertor or as a limiter in tokamak-reactors is investigated. The investigation has been performed by numerical methods. Spheric droplet strian and metal film behaviour in uniform magnetic field have been considered. The performed investigations enable one to determine the time of existence of liquid metal droplet incident in a magnetic field and flow condition of liquid metal film at the divertor or limiter plate as well as minimum thickness of such film

[en] The effect of energy dissipation by an electric field related to electron collisions on modulation instability in one-dimensional geometry is studied. In the linear approximation the modulation instability threshold has been found. It is shown that in the presence of collisions the isolated soliton damps with time. By means of numerical methods the dissipation effect on turbulent regime is considered when there are some caverns on a confined spatial interval. The presence of collisions results in instability development deceleration as compared with a non-collisional plasma. It has been found that when there are not many collisions when the modulation instability threshold is exceeded, dissipation caused by collisions does not stop oscillation energy increase under the pumping effect. The stationary regime is possible only under resonance absorption of oscillations by particles being in distribution function tail. Accounting for collisions may be essential in a dense plasma, for example during the laser thermonuclear synthesis

[en] Short communication

[en] The stability of the laminar flow of a liquid film in crossed fields is investigated in the nonionduction approximation

[en] Plasma ionization composition and level population calculations require, in particular, the cross sections of direct ionization from each quantum state into each state which may be generated by means of removal of any electron. We analysed published data and propose here an empirical formula for cross sections of direct electron-impact ionization of positive atomic ions. The cross sections given by this formula are in satisfactory agreement with those calculated in the distorted-wave (DW) approximation; therefore, we believe that for any direct state-to-state ionization channel this formula provides a reasonably accurate prediction of the DW result. Comparisons with published data and with the Lotz formula are reported as well. (author)