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1. The possibility of preparing low-molecular-weight ethers from silanediols and alcohols was established, and four compounds were synthesized: dibutoxymethyl-1-naphthylsilane (I), 1,3-dibutoxy-1,3-dimethyl-1,3-di-1-naphthyldisiloxane (II), l,5-dibutoxy-l,3,5-trimethyl-1,3,5-tri-1-naphthyltrisiloxane (III), and 7-butoxy-1,3,5,7-tetramethyl-1,3,5,7-tetra-1-naphthyl-1-tetrasiloxanol (IV). 2. The use of a vacuum in the synthesis of dibutoxymethyl-1-naphthylsilane from dichloromethyl-1-naphthylsilane and butyl alcohol has a substantial effect on the yield of this compound.

1. With a content in the steel of more than 0.08% residual aluminum the ductility at 900–1250°C is poorer and the tendency toward embrittlement at temperatures below 20°C increases. 2. An increase in the aluminum content aids in the formation in hardened steel of M2N nitrides and after tempering at 800°C of A1N phase. A drop in the ductility and toughness, especially at low temperatures, is caused primarily by the precipitation of nitride phases. 3. Calcium in a calculated quantity of 0.1–0.15% increases the ductility of the steel at hot working temperatures and does not influence the mechanical properties from 20 to −253°C. 4. An increase in the silicon content in the steel over 0.45% causes the appearance after heating to 1250–1350°C of a eutectic with an increased content of silicon and manganese. Heating after working should not exceed 1250°C. 5. To provide statisfactory production conditions for the investigated steel in hot working in combination with sufficiently high strength and ductility from 20 to −253°C the aluminum content in the steel should not exceed 0.06% and that of silicon 0.4%. For final deoxidation it is desirable to use calcium equal to 0.1–0.15% of the weight of the steel.

We examine the problem of ideal gas discharge from a cylindrical tube closed at one end into a vacuum, with unsteady mass and energy addition. The gas mass is formed by vaporization of the tube wall material due to the thermal flux from the heated gas. Under the assumption of uniform energy addition throughout the volume varying in accordance with the damped oscillation law, we obtain approximate relations for the mass of the discharging gas and the impulse of the pressure forces on the end wall as a function of time and energy. The resulting impulse values are compared with those determined for unsteady expansion into a vacuum of an ideal gas of given mass when energy is added to it. An increase of the impulse calculated by this technique in comparison with the value calculated using the proposed technique is shown.