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1. In the national pulse MHD generators with power from 10 to 600 MW, solid plasmagenerating propellants (SPPs) are used, which contain dibasic ballistite powders with an aluminum content of up to 21% (in mass) and an easily ionized seed like cesium or potassium nitrates (1-3). New SPPs should have increased values of the energy complex σv 2 (σ is the electrical conductivity, and v is the velocity) and the heat content of combustion products, which depends on their heat capacitance at constant pressure and the calorific power of the fuel. The value of the complex σv 2 depends mainly on temperature, while the heat capacitance is related to the combustionproduct composition and their degree of dissociation, which depends on the oxidizer excess factor α. The prelimi� nary study of new SPP compositions shows the possi� bility of a substantial increase in both the complex σv 2 and the coefficient α.

The sensitivity of the albedo electron method in density determinations on some P/M materials is equal to 0.1%. The method offers an accurate and rapid nondestructive means of examining the distribution of porosity in specimens. Use of an accelerator in determinations by this method ensures an appreciable depth of control, enables the size of the control zone to be varied, and increases control rate tens of times compared with the hydrostatic weighing technique.

The paper reports the results of measurements of the space-time properties of space charges in polymethyl methacrylate (PMMA) disks after a high-energy injection of electrons. Investigations by four independent methods (i.e., the through-probing, current, electrostatic, and sectioning methods) reveal that, first, the charge distribution is radially inhomogeneous regardless of the small ratio of the specimen thickness to diameter (1/10 to 1/30) and, second, space-time relaxation of charges occurs in a singular manner at diameters of 32, 65, and 130 mm.

Measurements have been made of the energy distributions of protons passing through NaCl, KCl, Si, and Ge single crystals at various angles with respect to the {100} and {110} planes. The fraction of protons passing through lattice channels has been evaluated, and its dependences on the angle of incidence, the chemical composition of the sample, and the proton energy have been found.

The effects of the amplitude nonuniformity of the magnetic field in a betatron on the forced and betatron radial oscillations of electrons during extraction (or discharge toward the target) at the end of the acceleration cycle are examined. The amplitude and phase dynamics of radial betatron oscillations are studied by means of an analog computer.

High-alumina, zircon, chamotte-kaolin, zirconia, and clay-graphite end nozzles were tested in a semi-continuous casting plant during the pouring of stainless steel in the pouring device, and SP-25 high-alumina and zircon nozzles were tested in the intermediate ladle.

Some preliminary experimental results on the acceleration of plasma in circular waveguides are reported. The experiments were carried out in the 10-cm region with H01 and H11 waves and with various plasma injectors. Plasma bunches with an initial particle concentration of 1012 cm-3 and higher were injected with an initial velocity of 5 × 106 cm/sec from a spark source or formed directly on the axis of the waveguide with the help of a pressure differential plasma source ensuring a vacuum in the accelerator corresponding to pressures in the range 10-7 to 10-6 mm Hg. Electric probes, super high-frequency methods and an electrostatic particle energy analyser were employed for diagnostic purposes. Plasma confinement was accomplished by the use of auxiliary external magnetic fields having various configurations. Accelerated ions with energies exceeding 10 keV were obtained.

The angular distribution of electrons having an initial energy of 6.74 MeV has been studied after passage through C, Al, Cu, Sn, and Pb samples having thicknesses in the range in which multiple-scattering theory does not apply.

A study was made of the channeling of 6. 72 MeV protons in a silicon crystal at 100–800 °K. The experimental dependence of the limiting channeling angle agrees with the theoretical prediction. A relation is found between the relative number of channeled protons and the temperature.

A magnetic β-spectrometer has been used for a thorough study of the energy distribution of electrons having an initial energy of 6.74 MeV after passage through C, Al, Cu, Sn, and Pb samples up to 0.5 R in thickness.