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A new phenomenon of a strong irreversible variation of the refractive index (?n~-0.2) in a skin layer (thickness ~300 Å) has been discovered. The effect arises under the strong absorption of high-power uv radiation (249 nm, 5 ns, 20 MW/cm2). The characteristics of the subsurface photorefractive effect (SPRE) were identified by using the data on measurements of the reflection coefficient of a crystal and of the diffraction efficiency of a recorded phase grating.

The interphase interaction force at low porosity was studied experimentally. Two methods are proposed for calculating the specific surface area of pores and for obtaining approximation relations for the resistance force and the Cozeni-Carman constant which are valid in a wide range of values of the parameters of the flow and porous layer.

A new model is proposed for the convective combustion of a porous fuel, which incorporates the deformation and dispersal of the porous matrix as well as the dissipative heating. Parametric studies have been made on the combustion of low-porosity and granulated charges. An experimental test agrees well with the model.

Development is reported of a UV-preionized electric-discharge XeCI laser with emission energy e ? 0.8 J (? = 308 nm). The energy and temporal characteristics of the laser are investigated, and the optimum gas-mixture composition for He as the buffer gas is determined. Ways of further increasing the XeCl-laser energy are indicated on the basis of the results.

The temperature dependence of the magnetic susceptibility has been recorded for the dodecaborides of terbium, dysprosium, holmium, erbium, and thulium over the range 90–1200°K. A theoretical model is tested, which is based on localized 4f electrons and the Van Vleck theory of paramagnetism. An explanation is suggested for the interaction between the rare-earth ions in the higher borides, which have the framework structure of boron itself.

Conclusions By calculation and semiproduction investigations it was established that in firing of kaolin into chamotte in a rotary kiln a significant increase in productivity, a reduction in fuel consumption, a decrease in dust burden, and an improvement in chamotte quality are obtained with briquetting of the raw material and heating of it to temperatures of occurrence of the dehydration reaction in a high-temperature layer heat exchanger using the heat of the outgoing stack gases.

Conclusions For ramming of the walls in combined lining of the 350-ton steel teeming ladles of Azov Steel Combine a composition and method of preparation of a mullite ramming compound applicable to the existing production conditions of Velikoanadol Refractory Combine has been developed.

This paper presents the actual problem of the dynamic interaction of a high-speed impactor with a screened explosive. The interaction mathematical model is based within the framework of continuum mechanics considering the mechanism of the shock-wave initiation of detonation in solid explosives. Testing of the method was conducted using experimental data in one dimension. Some problems of interaction of the conical impactor with the explosive protected one-layered and spaced metal barriers are numerically considered.

The title compounds LiMMo3O8(M: Gd‐Lu, Y) with hexagonal structure are prepared by heating stoichiometric mixtures of Li2MoO4, M2O3, Mo and MoO3under argon at 600‐750 °C for 4 d or by heating stoichiometric mixtures of Li2MoO4, M2O3, Mo and MoO2in evacuated quartz ampoules at 750‐850 °C for 65 h. The title compounds with M: Tm, Lu are prepared for the first time.