Depolymerization of chitin and chitosan in the course of base deacetylation

Depolymerization of chitin and chitosan in the course of deacetylation in an alkaline medium was studied, and the influence exerted on the process by the nature and concentration of the alkali (NaOH, KOH) and salts (NaCl, NaI, KI) was examined.     

Specific features of separate and joint mastication of natural and 1,4-cis-butadiene rubbers in the presence of dibenzoylaminodiphenyl disulfide

Variation of the molecular structure characteristics and properties of natural and 1,4-cis-polybutadiene rubbers (gel content, molecular weight, degree of branching of macromolecules, viscosity) in the course of their separate and joint mastication in the presence of dibenzoylaminodiphenyl sulfide as mastication accelerator or without it was studied.     

Reaction of 1-arylsulfamido-2-chloroethane with amines

Conclusion The reaction of 1-arylsulfamido-2-chloroethanes with diethylamine and aniline gives 1-arylsulfamido-2-aminoethanes.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 943–946, April, 1987.     

Influence of cobalt(III) dimethyldithiocarbamate complexes on styrene polymerization initiated by tert-butyl perbenzoate

Kinetic features of radical polymerization of styrene initiated by tert-butyl perbenzoate in the presence of tris(N,N-dimethyldithiocarbamato)cobalt(III) (CoL₃) and its adduct with iodine (CoL₃ · 2I₂) were studied. The optimal concentration ratios of the activators and tert-butyl perbenzoate, providing fast styrene polymerization at 338–368 K, were determined.     

Methods for creating the self-regulating mechanisms of passive systems for ensuring thermal regime of devices for space application

The passive systems for ensuring the thermal regime of space objects, which are in current use, can preserve the temperature at the same level only under a certain orientation of spacecraft and at a constant heat release of the equipment. At a variable orientation of the space object, its temperature may vary due to a possible illumination of the radiator-emitter of the system for ensuring the thermal regime by the solar or planet radiation. At a variable heat release the object temperature changes due to an off-design regime of the radiator operation. To compensate for the given effects the active elements are used — the heaters and coolers. This reduces the reliability of thermal regulation system and, consequently, the reliability of the entire spacecraft. The solutions are proposed, which create in the absence of active elements in the thermal regulation system the internal mechanisms enabling a compensation of the variability of heat fluxes both at a reorientation of the spacecraft and at a variation of the internal heat release.     

Influence of the energy and velocity spread in the electron beam on the starting conditions and efficiency of a gyrotron

We study theoretically the influence of the spread of initial energies and velocities in the electron beam on the starting conditions and efficiency of a gyrotron. We compare various analytical and numerical models and the results of experimental studies of gyrotrons in which the interaction takes place at the first and second harmonics of the cyclotron frequency. The aftercavity interaction of the electron beam with the high-frequency field in the output waveguide transition is taken into account. The influence of the energy spread on the recuperation efficiency is estimated. Permissible spreads of the initial energies and electron velocities are determined. __________ Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 49, No. 2, pp. 121–133, February 2006.     

Orthogonal decompositions of a space of symmetric tensors on an almost-Kählerian manifold

Kemerovo. Translated from Sibirskii Matematicheskii Zhurnal, Vol. 30, No. 3, pp. 131–139, May–June, 1989.