[en] In the paper the results of theoretical investigations of influence magnetic field of current branching-off systems on electron flow movement are represented. Investigation was carry our on example of two most typical devices: triode with virtual cathode, where current branching-off system is grid anode, and gas-filled systems of electron beam transporting to current-conducting target

[en] The effect of the anode-current magnetic field on the electron motion in a triode with a virtual cathode is considered. It is shown that the anode-current magnetic field influences the oscillation period and trajectories of electrons. The condition of self-isolation of the electron beam is investigated as a function of the diode parameter. It is shown that the displacement of the beam electrons under the action of the anode-current magnetic field leads to a decrease in the electron phase modulation and an increase in the spread in the electron oscillation amplitude; as a result, the generation efficiency of microwave radiation decreases

[en] Paper presents the investigation into phase modulation of electron flux and saturation of coherent emission in electronic flux at parametric excitation of oscillations within nonlinear system. Expressions for emission power of charged particle and emission in a resonator are obtained. Dependence of emission power and frequency on the external effort amplitude and frequency is studied

[en] Electron beams with high current density present a great interest for industrial and medical application because of its capacity to transport stored energy through rather long distance to the target objects without any noticeable losses. Besides, it is possible to control the beam parameters by means of external transporting conditions. In this work, the theoretical and experimental results due to additional external systems transporting investigation and focusing of electron beam propagation in the drift tube filled with plasma discharged at low pressure argon 10^-2 ∼ 10^-4 Torr were determined. The electrons movement equations in general case of nonuniform external field were analytically and numerically solved. It was obtained that the nonuniform of external magnetic field have noticeable role in transporting of electron beam. The experiments were conducted on several machines to determine the configuration influence of the magnetic field on compression (defocusing) of the beam. The experiments were realized also with application of two or three solenoids. The location of solenoids had been calculated theoretically. Experiments show possibility of compression of the beam, and increase in stability of the distribution of energy density on the irradiation area. The focusing of electron beam with initial angle speed spread tgΘ = v(perpendicular)/ v(parallel) = 0.26 (Θ ∼ 16^o) is shown. The radius of beam transporting envelope and longitudinal velocity of electrons essentially depends on the level of magnetic field gradient and the distance ratio between focuses and beam parameters. Changing of magnetic field can be governed by the energy density transferred to the beam collector. (author)

[en] The results of theoretical investigations of influence magnetic field of current branching-off systems on electron beam movement are represented. Investigation was carried out for two most typical devices: triode with virtual cathode, where current branching-off system is grid anode, and gas-filled systems of electron beam transporting to current-conducting target with shunt

[en] In this work there is presented the plasma channel forming model under the low-energy beam transporting in air with the pressure gradient along the beam motion in the external magnetic field. On the base of model there have been curried out the investigations of the effect of the gas pressure gradient and the magnetic field heterogeneity on the plasma channel forming and electron beam transporting

[en] One studies the effect of magnetic field of current supplying systems on electron motion and on envelope of an electron beam transported in a preliminary produced plasma within external magnetic field towards a current conducting target. One takes account of the normal-mode fields of an electron beam, the external magnetic field and the magnetic field of current passing along the target as electrons are precipitated. One obtained configuration patterns of a beam at the target depending on beam current, its current neutralization level, external magnetic field and orientation of current shunts

[en] The ladder-like DNA fragmentation pattern is detected by agarose gel electrophoresis in 3 h after the exposure of thymocytes to 4.5-Gy X-irradiation or 0.1 mM hydrogen peroxide. The content of accumulated high-molecular DNA fragments was higher in H₂O₂-treated thymocytes, while he content of oligonucleosomal fragments was higher in X-irradiated cells. The MTT test showed hat the incubation with hydrogen peroxide induced the earlier inhibition of mitochondrial respiratory chains, which preceded the DNA fragmentation in thymocytes

[en] The transport and focusing of low-energy electron beams with effective transfer of stored energy in low-pressure ionized argon are investigated under the conditions of a high degree of charge neutralization in an external longitudinal magnetic field. It is shown that a nonuniform magnetic field provides the range of parameters, where it proved possible to tightly stabilize the position of the maximum of the beam on the target and, if necessary, compress the beam. It is demonstrated that the parameters of the electron beam can be controlled by selecting the configuration of the magnetic field appropriately matched to self-fields

[en] At present, the virtual cathode systems (vircators) are used for generation of powerful emission. One of peculiarities of the magneto-insulated diode vircator is the generation possibility on the two frequencies. In particular, it can be used for plasma heating of fusion plasmas. In present paper the two-frequency generation mechanism for increasing of emission efficiency and realizing of the emission parameters operating is investigated. The problem has been investigated by means analytical and numerical methods. It has been shown that two-frequency generation regime is conditioned by two virtual cathodes forming. In result, the nonsymmetrical potential well is formed in which the flow electrons are captured. It has obtained that the depth of the potential well and emission power are considerably higher for the foil system in comparison with foilless system. The dependencies of frequency spectrum and efficiency on system geometry and external magnetic field have been determined. It has been shown that the frequency spectrum and emission power do not depend on drift tube length if it exceeds the Debye radius calculated with taking into account the reduction coefficient. The influence of transverse impulse and velocity spread on efficiency are studied. Comparison of theoretical results with experiments is carried out