Impurity phases in beryllium oxide ceramic

An x-ray spectrographic method with an electron probe and a scanning electron microscope are used to study industrial ceramic specimen surface composition, distinguished by presence of a different color for both the main part, and impurity phases. BeO-ceramic specimens, having a visually differing color, are conditionally separated into three types. In reflected electron microphotographs impurities are distinguished qualitatively with respect to electrical conductivity. Iron impurity is invariably present within the composition of electrically conducting phases and inclusions. Apart from iron, all impurity phases contain carbon, aluminum, silicon, and calcium, and within individual phases there are admixtures of manganese, magnesium, chromium, potassium, sodium, zinc, phosphorus, and chlorine, which may be introduced into BeO-ceramic during production and sintering in repeatedly used industrial furnaces from linings and residual atmosphere. © 2013 Springer Science+Business Media New York

LAYERED-FIBROUS COMPOSITE BASED ON NIOBIUM REINFORCED BY SAPPHIRE FIBERS

A structure was developed and specimens of composite materials with a niobium.based layered matrix, unidirectionally reinforced with single.crystal sapphire fibers, were obtained by the solid.phase method of diffusion welding. X.ray microanalysis and mechanical tests of the obtained materials were carried out.Разработана структура, и твердофазным методом диффузионной сварки получены образцы композитных материалов со слоистой матрицей на основе ниобия, однонаправленно армированные монокристаллическими волокнами сапфира. Проведены рентгеноструктурный микроанализ и механические испытанияполученных материалов

Electrodynamic characteristics of the nonresonant system of transverse slots in the wide wall of a rectangular waveguide

The method of induced magnetomotive forces is applied to the problem of electromagnetic wave radiation by a system of transverse slots located in the wide wall of finite thickness of a rectangular waveguide. The paper includes calculation of space-energy characteristics of linear multislot nonresonant antenna arrays of the leaky wave. Comparison of the numerical results, obtained by Galyorkin’s method, with the experimental data is performed

The multi-band reflector antenna of the double-polarization scanning radio aerospace radiometer

The paper describes a 13-channel reflector antenna operating in six subbands of wavelengths from 3 mm to 4.5 cm in two orthogonal linear polarizations for the scanning aerospace radiometer