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We present a new type of waveguide bandpass quasi-elliptic filter whose resonators are implemented by thin transverse resonant diaphragms with an aperture in the form of a rectangular windo...

The thermal transitions, microphase structure, local segmental and conductivity relaxation of the novel polyurethanes (PUs) based on the poly(tetramethylene glycol) as soft segments (SSs) and 4,4′-diphenylmethane diisocyanate-1,4-butane diol sequences of various length as hard segments (HSs) containing ionic groups in SSs are studied by calorimetry, X-ray scattering and dielectric relaxation spectroscopy.

The proportional phase conversion of a measured interferometrie phase shift on the intermediate frcquency using double-freauency plasma probing is proposcd in order to overcome problems encountered in the course of interferometer measurements under high-density regimes in tokamaks (fringe “jumps” due to high density rise rate, large phase shifts to be measured, etc). The method is based upon an opportunity of multi-frequency lasing (e.g., DCN laser). Basic scheme of such an interferometer is described. Estimations of influence of the frequency stability or radiation sources and signal-to-noise ratio on the aceuracy of phase measurements are given. Relative simplicity of the optical circuit allows easily to extend the technique to apply it for multichord measurements of the plasma density and for measurements of Faraday rotation angle. Double-frequency laser interferometer with an unambiguous phase reading can be used as a line integral density monitor on the ITER facility, especially for a densit...

edited by J. S. Lewis, M. S. Matthews, M. L. Guerrieri The University of Arizona Press/Tbcson & London, 1993, 977 pp.

Our present cheerless existence compels us involuntarily to doubt the correctness of many of the propositions of the Soviet "social philosophy" that for many years, under the title "historical materialism," was officially proclaimed to be the "only correct" and "truly scientific" theory of social development, a theory that demonstrated the inevitability of the replacement of capitalism by socialism.

When the Nineteenth All-Union Party Conference was taking place, tens of millions of people followed its course. Literally the entire country was drawn into those heated debates in the congress hall. One can say without exaggeration that the conference was a revelation. It showed that it is possible to live differently from the way we have been accustomed, or the way we have learned over many decades, i.e., to say what we think and what we want to say, not somewhere in a back corridor but in public, even at a top Party forum. All this is the result of that mighty revolution in consciousness that began in people's minds that memorable April of 1985. And the press is today playing a special role in that revolution.

edited by V. L. Barsukov, Senior Editor, A. T. Basilevsky, V. P. Volkov and V. N. Zharkov The University of Arizona Press/Tucson & London, 1992, 421 pp.

edited by T. M. Donahue with K. K. Trivers, D. M. Abramson National Academy Press, Washington D. C.1991, 293 pp.

We present some results of the long-term photometric program ROTOR being carryed out at the Mt. Maidanak observatory. The program seeks for a periodic components in the emission of the non-stationary T Tauri-type stars (TTS), HAEBE, FUORs and related objects. In this paper we analyse the results concerning TTS in Rho Oph dark clouds and vicinity. Our sample of stars includes 6 weak-emission TTS (WTTS) and 11 classical TTS (CTTS).

From the Editors of Voprosy filosofii: A little more than half a year remains before the Twenty-seventh Congress of the CPSU. As was stressed at the April (1985) Plenum of the CPSU Central Committee, the coming congress will be a landmark stage in the development of the country. Its significance is determined by the character of the period being experienced and the scale of the tasks before us, which give special significance to the pre-Congress work of the Party. All this demands a profound scientific study of the realities of the present day and a thorough comprehension of the prospects of socialist and communist construction, in particular of the profound qualitative shifts in the development and functioning of the economy and the social relations of developed socialism.

The main results of the present study confirm the ideas previously proposed by us to explain electric field effects in ionic polymerization, namely, that they are mainly caused by space distribution of the ions present in the system at the moment of field application. Polymerization of 1,3-dioxolane by SnCl4, (C2H5)2- OBF3, and (C6H5 ) 3 CSbF6 and also of styrene by (C6H5)3CSbF6 was studied. The ratios of the rate constants of free ions and ion pairs and approximate values of the constants were calculated. The possibility of secondary initiation in the system styrene-(C6H5)3 CSbF6 was found, probably due to the discharge of SbF6 counter ion at the anode. The data show that a transition to a new polymerization rate occurs in a definite time period dependent on the velocity of the space distribution of counter ions or ions of both signs. This fact makes it possible to treat the proposed method of the analysis of electric field effects in polymerization kinetics as a relaxational one.

Investigations were made which show that the change in the dynamics of polymerization and in molecular weight of the polymer under an electric field is connected with the redistribution of the ions growing macromolecules and counterions. Analysis of the equations obtained showed that the field can either increase or decrease the rate of the process. The effect's trend and magnitude depend on the ratio of the mobilities of macroions and counterions, degree of dissociation of active centers, and the ratio of rate constants of free ions and ion pairs. An analysis of literature data relevant to polymerization under an electric field was made.