A method of successive approximations for solving the quasi-variational Signorini inequality

We solve the semicoercive quasi-variational Signorini inequality that corresponds to the contact problem with friction known in the elasticity theory by a method of successive approximations. For solving auxiliary problems with a given friction occurring on each outer step of the iterative process we use the Uzawa method based on iterative proximal regularization of a modified Lagrangian functional. We study the stabilization of the sequence of auxiliary finite-element solutions obtained on outer steps of the method of successive approximations and present results of numerical calculations.     

Diffraction of stationary cylindrical and plane sound waves by a cylinder in a viscous heat-conducting medium

The diffraction of cylindrical and plane stationary sound waves by a cylinder in a viscous heat-conducting medium is analyzed. A solution of this problem is given in [1] without regard for heat conduction.Tula. Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 3, pp. 147–154, May–June, 1972.     

Positron annihilation in Si and GaAs crystals with an applied magnetic field

The narrow components in angular correlation curves of positron annihilation in Si and GaAs were observed. Hence it follows the formation of positronium-like states in semiconductors. Effects of mechanical and radiation treatment of the samples of Ps-states are discussed.     

Molecular and crystal structure of 2-para-toluimido-4,4-dimethyl-(4H)-1,3-thiazine

The imino structure of 2-p-toluimido-4,4-dimethyl-(4H)-1,3-thiazine (I) was demonstrated by x-ray diffraction structural analysis. Molecules of I in the crystal are linked by N-HO hydrogen bonds in infinite chains. A shortened SO intramolecular contact was found which corresponds to a secondary interaction. A mechanism was proposed for the thiazoline-thiazine rearrangement.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1638–1643, December, 1984.     

Characteristic features of the reaction of 3(5)amino-5(3)-methylpyrazole with 1-nitroanthraquinone-2-carboxylic acid

In the reaction of 3(5)-amino-5(3)-methylpyrazole with 1-nitroanthraquinone-2-carboxylic acid in sulfolane at 150°C, 2-methyl-pyrazolo[5,1-b]naphtho[2,3-h]quinazoline-5,10,13-trione is formed with an admixture of 1-aminoanthraquinone-2-carboxylic acid and 1-aminoanthraquinone. Under similar conditions, from 4-amino-1,5-dimethylpyrazole, only 1-(1,5-dimethyl-4-pyrazolylamino)anthraquinone-1-carboxylic acid is formed.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1191–1192, September, 1992.     

Anomalous energy dependence of the electron relaxation time in bismuth

The relaxation time of highly nonequilibrium electrons whose excitation energy |Δε| is of the order of the Fermi energy ε _F is measured. The measurements are made on bismuth samples with the aid of transverse electron focusing with micron intercontact separations. The dependence of the electron collision frequency on the excitation energy is found to be close to linear. The possibility of observing the topological restructuring of a closed isoenergetic surface into an open surface in Bi with an increase in the electron energy is discussed. Pis’ma Zh. éksp. Teor. Fiz. 64, No. 12, 835–840 (25 December 1996)