Broad-beam plasma-cathode electron beam source based on a cathodic arc for beam generation over a wide pulse-width range.

We describe the design, parameters, and characteristics of a modified wide-aperture, plasma-cathode electron beam source operating in the pressure range of 3 Pa-30 Pa and generating large-radius, low-energy (up to 10 keV) electron beams with a pulse width varying from 0.05 ms to 20 ms and a beam current up to several tens of amperes. A pulsed cathodic arc is used to generate the emission plasma, and a DC accelerating voltage is used to form the electron beam. Modernization of the design and optimization of the operating conditions of the electron source have provided a multiple increase in the pulse duration of the electron beam current and the corresponding increase in the beam energy per pulse, as compared to previously developed pulsed forevacuum electron sources.

[The microbiocenosis of the large intestine in animals with constant radiation exposure in the area of the Chernobyl Atomic Electric Power Station]. / Mikrobiotsenoz tolstogo kishechnika zhivotnykh pri postoiannom radiatsionnom vozdeistvii v zone ChAES.

State of microbiocenosis of large intestine in rats and furo subjected to constant combined irradiation has been studied in full-scale experiments in the emergency rooms of the Chernobyl NPP and in the nearest zone of its effect. The higher diversity of microflora (as compared to initial one), sharp increase of the amount of Candida genus fungi, a decrease of the number of bifidobacteria and increase of the amount of conditionally pathogenic flora were observed in rats with the dose of external irradiation of 1.43 Gr absorbed for 14 days. The expressed associative character of disbioses is distinctly traced. In furo affected by the radion exceeding the background level feeding with products contaminated by radionuclides leads to changes whose individual character corresponds to the picture of disbiosis under radiation injury.

[Heterophilic granulocytes of rats during irradiation]. / Geterofil'nye granulotsity krys pri obluchenii.

The bone marrow eosinophils of rats subjected to irradiation are capable of secreting a peroxidase system obtained by neutrophils and endotheliocytes. As a result, there appear heterophil granulocytes in the peripheral blood.

[Structure of thymus and bone marrow lymphocytes in explants]. / Struktura limfotsitov timusa i kostnogo mozga v éksplantatakh.

A comparative electron microscopic and morphometric investigation of lymphocytes has been performed. They are taken from the growth zones of the in vitro cultivated explants of the rat thymus and the bone marrow. Their main ultrastructural differences concern the form of the cells, electron density of the nuclei and presence of organelles. In the lymphocytes of the thymus intraplasmic nuclear fragments are revealed.