Comparison of the methods for computing interference elastic wave fields in thin-layered media. 1

A nonstationary problem concerning the propagation of low-frequency waves for a model that consists of a packet of elastic layers lying on an elastic half-space is considered, and exact mathematical solutions in the form of repeated integrals are constructed in three basic forms. It is proved that these solutions satisfy initial conditions. The representation of solutions as a superposition of multiple waves is treated. Bibliography: 6 titles. __________ Translated from Zapiski Nauchnykh Seminarov POMI, Vol. 332, 2006, pp. 220–239.     

Annihilation of positrons in hydrogen-saturated titanium

The effect of atomic hydrogen on the electronic structure of α-titanium samples is studied using the electron-positron annihilation methods. It is shown that different states of hydrogen atoms are manifested in different ways in the positron lifetime distribution spectrum. The results of theoretical calculations of the first component of the positron lifetime are in accord with the obtained experimental data.     

127I nor spectra of iodotrinitromethane complexes with organic ligands

Conclusions Iodonitromethane forms n complexes with organic ligands with low¹²⁷I asymmetry parameters and positive charge on the iodine atom.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 12, pp. 2790–2792, December, 1984.     

On functional-differential equations with discontinuous right-hand side

We consider unique determination and right uniqueness issues for solutions, satisfying the one-sided Lipschitz condition, of functional-differential equations with discontinuous right-hand side.     

Determination of the strength of the intramolecular electric field of the NO2 group by the NQR method

Conclusions Comparison of the investigated NQR spectra of the halogen atoms in a series of methane nitro derivatives with the field constants of the halogen atoms makes it possible to estimate the averaged intramolecular electric field created by the NO₂ group.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 769–772, April, 1981.     

Asymptotics of regularized solutions of a linear nonautonomous system of advanced differential equations

For a nonautonomous system of linear advanced differential equations, we find asymptotic formulas analytically determining how the regular solutions of this system on an interval of the positive half-line depend on the admissible error. The problem is solved in the following setting: additional smoothness conditions are imposed on the initial functions, but the boundary conditions providing a continuous extension of the solutions of the Cauchy problem to an interval of the positive half-line are violated.     

Synthesis and free-radical polymerization of water-soluble acrylamide monomers

Water-soluble acrylamide monomers N-(hydroxymethyl)acrylamide, N-(hydroxymethyl)methacrylamide, N,N-diethanolacrylamide, N,N-diethanolmethacrylamide, N,N-methylethanolacrylamide, and N,N-methylethanolmethacrylamide have been synthesized and characterized. The kinetics and thermodynamics of the free-radical polymerization of these monomers and of the model compounds N-isopropylacrylamide and acrylamide have been studied by the methods of isothermal and scanning calorimetry. The structure and the solubility of the said polymers in water and organic solvents have been investigated and their molecular-mass characteristics and temperatures of glass transition (T _g) and melting (T _m) have been examined by DSC, liquid chromatography, ¹H NMR and IR spectroscopy, and chemical analysis of functional groups. Hydrogels and amphiphilic network polymers based on acrylamide monomers have been prepared and characterized.     

Azanorbornenes in radical polymerization reactions

Activity of azanorbornenes: N-benzyl-2-azanorborn-5-ene, (2-azanorborn-5-en-2-yl)methyl acetate, and N-allyl-2-azanorborn-5-ene in radical homo-and copolymerization with vinyl monomers and sulfur dioxide was studied.