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The high-voltage pulse modulator based on the modern semiconductor elements is described. The modulator is intended for use in the power supply system of LINAC helium ions injector and has the ability to smoothly adjust the amplitude (110…150 kV) and the pulse duration (0.5…1 ms). The use of a pulse-to-peak stabilization scheme, made on the basis of a parametric stabilizer with parallel switching of the load, made it possible to increase the accelerated current at the accelerator output by 2 times.

Irradiation of titanium was performed with high power electron beams. The electron energy was 800 keV, the pulse duration was 10 ns and energy density injected into the sample by one pulse was 20 J cm−2. Hardness measurements of irradiated samples permit the detection of two different modified layers. The hardness of these two layers depends on the pulse number. The states of stress and the grain size in irradiated samples were determined by X-ray diffraction. XRD shows the presence of the high pressure ω phase in titanium after power electron beam exposure. The explanation of the results is based on stress waves, which arise due to such exposures. The observed hardening of irradiated titanium is a result of an intensive process of twinning produced by shear stress waves.

The possibility of forming and emitting high-power electromagnetic pulses by means of an insulated rod antenna excited by a short-duration high-current electron beam is studied. It is found experimentally that the amplitude of the emitted pulses and their characteristic period depend on the antenna length. The potentialities of the method proposed as applied to the generation of intense videopulses are discussed.

Design features of a test bed with an operational volume of 1 m/sup 3/ for ultra-short pulsed (USP) electromagnetic compatibility (EMC) tests of radio-electronic equipment (REE) are presented.

In this paper we studied the biological effect of superwideband EM radiation and high-intensity pulse upon the seeds of barley and spring wheat.

Summary form only given, as follows. The excitation of a TEM-horn antenna by a pulsed intense relativistic electron beam (IREB) has been explored for powerful electromagnetic irradiation. Similar investigations for coaxial geometry have already been carried out. In the present work the parameters of the IREB were varied in the following range: energy 500-700 keV, current 3.5 k/spl cong/, time duration 15 ns, risetime did not exceed 1.5 ns. It was observed, that the radiation signal of the antenna contained three various components caused by, respectively: transient radiation of the IREB front, high-voltage oscillating discharge between plates of TEM-horn antenna, and, response due to resonant properties of the antenna device.

The influence of a short high-power electromagnetic videopulse on a suspension of hepatic cells of 9-weeks human embryo has been investigated. Such pulse was generated by an electron beam of the accelerator "Temp-A" with energy 0.6 MeV, current 4 kA, and time duration 40 nsec falling to rod antenna of 3 m length. The output power was 100 MW. The samples were placed perpendicular to the antenna at 30 cm distance from its center. The free-radical state in the system "hepatocite+hypochlorite" has been investigated using the quantum-metrical set with photo-electronic amplifier FEU-140 in a thermostat box at 37/spl deg/C. The appearance of radical fragments in this system was registered by means of 630 nm spectral line of generated single oxygen. The estimation of the cell viability before and after irradiation was performed using the method of supravital staining by methylene dark blue. It was shown that the influence of video-pulse treatment decreases the percentage of the viability of the hepatocites and activates the free-radical processes and correspondingly enhances the single oxygen generation. The dependence of these processes on the video-pulse power was determined.