A nonlinear theory is developed for the propagation of elliptically polarized waves in a homogeneous unbounded plasma, based on Vlasov's equations.
Show AbstractCalculations are given which describe the refraction of normal waves in a wedge. The results of these calculations are in good agreement with experiment, as can be seen from the accompanying oscillogram.
Show AbstractThe maximum attainable conversion efficiency η_n of n-fold frequency multiplication in an exponential resistance with a supplementary circuit tuned to the k-th harmonic is always less than when there is no such circuit. The influence of the supplementary circuit is least when its resistance is either very small or very large. If k<n, for a given resistance of the supplementary circuit, η_n is zero for any load R_n. If k>n, the reduction in efficiency η due to the supplementary circuit is less significant than when k<n. The basic conclusions of the theoretical analysis agree with the results of an experimental study of a frequency multiplier.
Show AbstractThe optimal tracking of a differential type random signal with drift is examined. A noisy communication channel with one unknown parameter is assumed. A close-to-optimal system using self-adjustment to the unknown parameter is shown to be synthesizable. This system is analyzed approximately, and electronic simulation of it is described.
Show AbstractA solution of the equations of electromagnetic cascade theory in the small angle approximation of multiple scattering with arbitrary bound ary conditions is described. The cross sections of the basic processes of retarded radiation and pair formation are taken in the Bethe-Heitler form, and the polarization of the medium is taken into account. The solution for the primary electron is examined and justified for finite values of the ratio E/E0.
Show AbstractAn approximation for the kernel of the linearized Lenard equation is obtained and used to obtain an expression for the Green's function. The asymptotic value of this for small к is obtained exactly, together with the eigenfrequencies and damping of the system when spatial dispersion is present. An asymptotic value for the spectral density is derived.
Show AbstractThe displacement of the maximum of the mean radiation pattern relative to the maximum when there are no random variations in the amplitude and phase distribution of the antenna sources is derived. The theoretical results agree with the experimental data given in [1].
Show AbstractA new method of solving Vlasov's equation for a crystal is examined. The advantage of this method is that it is possible in some cases to obtain a solution of this equation in finite form for any temperature, which does not contain series. In other cases the solution of the equa tion is found in the form of a series for a certain small parameter which does not contain the temperature. This method enables the solutions obtained by Vlasov for two limitiag cases to be connected.
Show AbstractIt is established that the paraprocess and the blurring of the magnetic transitiorr at the Curie point in nickel-zinc ferrites $Ni_(1-x)Zn_xFe_2O_4$ having a large zinc content increase considerably in comparison with ferrites containing small amounts of zinc. Apparently the reason for this is an increase in the exchange interaction between sublattices. Using the method of thermodynamic coefficients we have determined more accurate values for the Curie temperature of nickel-zinc ferrite systems. This enabled us to establish that there is no ferromagnetism in this system when x = 0.81, and not when x= =0.16 as stated in [5).
Show AbstractThe effect of the dielectric constante of the solvent on the association of molecules of the dye rhodamine-6G was studied by means of elec tron and vibration absorption spectra. It is shown that under otherwise equal conditions a reduction in the e of the medium leads to a rein forcement of the association of dye molecules. This coofirms the cor rectness of the assumption that in concentrated solutions there is an amalgamation of ion pairs of the dye.
Show AbstractAn analysis is given of the absorption characteristics of a three-dimensional spherical absorbei, and it is shown that the latter should have a maximum absorption. Nomograms are given from which it is possible to calculate the sound absorption coefficient with given absorber pa rameters (radius of the sphere or the edge of the cube and the im pedance of its surface)or, on the other haod, to find the parameters needed to obtain a desired absorption characteristic in the field of a plane wave and in the sound diffusion field.
Show AbstractOn the basis of the nonlinear theory of irreversible processes previously developed, the relationships which link the diffusion coefficients of the internal thermodynamic parameters with the nonlinear terms of the phenomenological equations for their mean values are investigated. The theory is illustrated by means of examples.
Show AbstractThe scattering of relativistic electrons at a spherically symmetrical force center in a uniform magnetic field is considered. It is assumed that the initial state of the electron corresponds to motion strictly along the field.
Show AbstractThe main properties of the root loci of linear delayed systems are found, including the equations of the loci and formulas for the free parameter, whereby the root loci can be plotted (geometrically and analytically) and the value of the free parameter determined at any point of the locus. Examples are considered, showing how the main properties of the loci of systems of different classes may be used to find the regions of stability, the variation in the magnitude and nature of the degree of stability, the critical values of the frequency and free parameter, and the transients in the system.
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