Gyration Waves in Optical Crystals

The optical activity of crystals can be explained by energy transfer from radiation incident on the crystal into the radiation mode (gyration wave) propagating in the incident wave direction but having the polarization plane perpendicular to that of incident radiation.__________Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 1, pp. 6–10, January, 2005.     

Tetrahedron equation and spin integrable models on a cubic lattice

This paper is a survey of results on the three-dimensional generalization of the Yang-Baxter equation obtained since the pioneer works by Zamolodchikov (1979) up to our articles in 1995. The integrability condition for statistical spin models on a simple cubic lattice (tetrahedron equation) is discussed and different versions of this equation are considered together with their symmetrical properties. The solution of the tetrahedron equation corresponding to the Bazhanov-Baxter model is considered in detail. The review contains an updated list of solutions for this equation. Generalization to inhomogeneous spin models with two types of Boltzmann weights forming a chessboard-type lattice is considered. The paper was written at the request of the Editorial Board. Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 110, No. 2, pp. 179–213, February, 1997.     

Trigonometric and Sn symmetric solutions of triangle equations with variables on the faces

General properties of triangle equations with variables on the faces have been considered. A simple method to search for the solutions of these equations is offered. Some examples of applying this method in the case of the general vertex model with the three colors as well as for S_n symmetric model are given.     

Modification of epoxy-amine compositions on the basis of water-soluble resin

Water-soluble epoxy-amine compositions have been synthesized. The possibility of modification of water-soluble hydantoin-containing epoxy resin marketed under the brand name SEG-6 with such products as medium-molecular-weight epoxy resin under the brand name Epofom-1s and high-molecular-weight polymers, namely, petropolymeric resin under the brand name Quintone C200S and CSPE-MK chlorosulfonated polyethylene, is studied. It is shown that the compositions produced as a result of such modification are water-soluble and exhibit a long lifetime, and the materials obtained on their basis are characterized by high elastic-deformation and adhesive properties in comparison with polymers on the basis of SEG-6 resin.     

Experimental investigation of the oscillator strength of the exciton transition in GaAs single quantum wells

A technique that makes it possible to investigate the mechanisms of phase relaxation of excitons in GaAs single quantum wells has been developed using resonant reflection spectroscopy. The dependence of the oscillator strength of the exciton transition on the quantum well thickness has been measured in the thickness range 9.1–30.0 nm. It has been demonstrated that the oscillator strength with a high accuracy does not depend on the temperature in the range 8–90 K. The temperature dependence of the homogeneous broadening has been measured, and the inhomogeneous broadening of the resonance exciton line has been determined. A nonmonotonic dependence of the spectral broadening of the exciton line on the intensity of the resonant excitation at a temperature of 8 K has been revealed for the sample with a high-quality quantum well. It has been established that an increase in the excitation level by five orders of magnitude above the linear limit leads to an insignificant change in the oscillator strength of the exciton transition and to a multiple broadening of the spectral line profile.     

Adhesive technologies in repairing polyethylene pipelines

Adhesive technologies for repairing polyethylene pipelines are considered taking into account the peculiarities of gluing of substrates with a low surface energy. An epoxy composition is suggested based on the modified binder for application in the gluing repair technologies under consideration. It is shown that complex use of preliminary processing of glued surfaces and the composition that was developed allows an increase in the strength parameters of adhesive joints of polyethylene pipelines to be achieved.     

Combinatorial Nature of the Ground-State Vector of the O(1) Loop Model

Studying a possible connection between the ground-state vector for some special spin systems and the so-called alternating-sign matrices, we find numerical evidence that the components of the ground-state vector of the O(1) loop model coincide with the numbers of the states of the so-called fully packed loop model with fixed pairing patterns. The states of the latter system are in one-to-one correspondence with alternating-sign matrices. This allows advancing the hypothesis that the components of the ground-state vector of the O(1) loop model coincide with the cardinalities of the corresponding subsets of the alternating-sign matrices. In a sense, our conjecture generalizes the conjecture of Bosley and Fidkowski, which was refined by Cohn and Propp and proved by Wieland.     

Biodeterioration of polymers and polymer composite materials

The problem of the biodeterioration of polymers and polymer composite materials is considered. Products made from both thermoplastic and thermosetting polymers are found to undergo biodeterioration. An analysis of methods for investigating biocorrosion is performed. It is established that the application of conventional testing methods under laboratory conditions is restricted due to their complexity and work content, as well as because of the low efficiency at the stage of material development. In connection with this, the possibility of applying indirect investigation methods for the qualitative and quantitative evaluation of biodeteriorations of polymers is considered, and testing is carried out on samples of crosslinked polymers in aerotanks. It is shown that biocorrosion is not caused by the microorganisms themselves, but rather by their waste products, e.g., organic acids and ferments. The possibility of evaluating biocorrosion via modeling biodeterioration using solutions of individual substances (various organic acids) is revealed. Urgent problems of investigations on this topic are defined.