Development of a crack created by hydraulic fracturing in a compressed block structure rock

The authors estimated trajectory of a created crack in a block-structured rock mass during hydraulic fracturing, and analyzed effect of the parameters of the block medium and two-axis compression field on the main crack trajectory and on the opening of lineal segments of the crack.     

On the development and linking of two initially parallel rectilinear cracks

Mining Institute, Siberian Branch, Academy of Sciences of the USSR, Novosibirsk. Trans lated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 4, pp. 14–23, July–August, 1989.     

Activation of Anticorrosion Oligomer-Containing Synergistic Cutting Fluids Based on Secondary Raw Materials

We study the possibility of improving the anticorrosion activity of synergistic oligomer-containing cutting fluids based on secondary raw materials. It is shown that cutting fluids with admixtures of heterocyclic synergists (derivatives of 1, 2- and 2-benzimidazole) improve the physicomechanical properties of 20 and 45 steels after turning and grinding and increase their resistance to corrosion–mechanical fracture in corrosive media.     

Stabilizing the pressure in the delivery system for coke-oven gas

A system for stabilizing the pressure in the delivery system for coke-oven gas using a compressor and a receiver has been developed. The gas is stored under an excess pressure of up to 40 kPa. The necessary volume and dimensions of the stores are determined, as well as the number of stores required. Optimal operation of the delivery system for the coke-oven gas is considered.     

X-band circular waveguide switch with polarisation diversity

A p?i?n diode X-band circular waveguide SPST switch with polarisation diversity has been designed, fabricated and tested. Special design of the bias circuits ensures minimum insertion loss, better than 0.1 dB, and maximum isolation of 29 dB at X-band frequencies.     

Smart Selection of Milling Strategies for Complex Aircraft Components

Russian Engineering Research - In milling, the strategy for removing the residual margin in enclosed areas affects the machining time and the tool load; the specifics of that influence are studied...     

Physicochemical Properties of the Surface Layers of 40Kh Steel After Hydrogen-Free Nitriding in Glow Discharge

Materials Science - By the methods of mathematical statistics, we deduce equations specifying the relationship between the technological parameters of hydrogen-free nitriding in glow discharge...