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A description is given of a superconducting current comparator, with zero-element based on a SQUID. The method is described, an evaluation made of the error, and results reported of a study of the stability of resistive dividers made with type S5-61 resistors. It is shown that these resistors can be used in the electric current and voltage dividers employed in precision measurements at the boiling point of liquid helium.

A set of instruments for reproduction and storage of the emf and dc voltage unit and for transferring it directly to the location where measuring instruments (MIs) are used with an accuracy of (3–5) ·10−7, developed at the “VNIIFTRI” Research and Production Association (RPA) is described. The metrological characteristics of the set are investigated.

The action of protons and electrons on the properties of glass strands under vacuum conditions has been experimentally investigated. The experimental procedure is described. The effects of irradiation, strain rate, and reduced temperature and pressure on the properties of glass reinforcement and glass-reinforced plastics are estimated.

The stability of cylindrical shells in axial compression has been experimentally investigated. The glass-reinforced plastic shells were fabricated in various ways: by winding glass strand, from glass cloth, and by a combination of the first two methods. The buckling mode and critical load were determined as functions of the ratio of shell radius to shell thickness. A statistical analysis of the test data leads to a formula with an empirical coefficient for use in practical stability calculations.

The design and fabrication of lens-shaped tanks are described. The results of an investigation of the deformation and strength of the tanks are presented together with the data of cyclic tests.

It is shown that removing paraffin size from the glass strands by means of ultrasound has little effect on their strength, improves the structure of the material, and raises the mechanical strength of the GRP by 11–12%. An ultrasonic strand cleaner employing focusing piezoelectric ceramic transducers is described.

The effect of certain aggressive media on the wear of glass-reinforced plastics has been investigated. It is shown that as the angle of inclination of the glass reinforcing fibers relative to the friction surface increases, the wear of the material is sharply reduced.

Experimental data are used as the basis for a discussion of some of the technical factors affecting the strength of filament-wound glass-reinforced plastics (GRP): winding speed, tension on the glass, life of resin. A relationship between the strength of GRP and these factors is demonstrated. The effect of the thickness and diameter of the test piece on the tensile strength of GRP material is examined.

Values of heat conduction coefficients for W and graphite at various temperatures were obtained experimentally and theoretically. The heat conduction coefficients decreased with rise in temperature for both materials between 900 and 2200 C. The specific electric resistance of these substances increased through the range 9002200 C. The Lorentz number for W between 900 and 2200 C is above the theoretical value and depends approximately upon temperature.

The authors investigate the influence of certain aggressive media (toxic chemicals) on the wear resistance of filled epoxypolyamide composites. The presence of toxic chemicals in the zone of friction causes a sharp fall in the wear of the polymers. The maximum wear resistance is displayed by epoxypolyamide composites filled with iron powder, cement, or graphite.