Equilibrium failure processes of granular composites

The macroscopic failure of inhomogeneous media results from damage accumulation on different structural levels. During rigid loading, when given displacements of boundary points are ensured, irrespective of the body's resistance, structural-failure processes of composite materials take place in an equilibrium regime and result in the manifestation of such nonlinear-behavior effects as a descending branch on the strain diagram. the structural elements of a granular composite are homogeneous and firmly connected along the interface. Their geometry and mutual arrangement are given and do not change during deformation and failure of the medium, and the medium itself is macrohomogenous. The strength of isotropic structural elementsis estimated by comparing the second invariant of the stress tensor with its critical value. Nonfulfillment of the indicated strength criterion is associated with loss of ability to resist changes in form; at this point, the positive value of the first invariant corresponds to loss of such ability to resist and increase in volume. The deformation and structural failure of the medium are investigated as a single process that can be described under quasi-static loading by a boundary problem consisting of a closed system of Eqs. (1) and (2) and boundary conditions providing for a macrohomogeneous strain state. A principal feature of the boundary problem under consideration is the possibility of considering in constitutive relationships the states of the inhomogeneous medium, which correspond to partial or complete loss of bearing capacity of the structural elements. The random structural strength constants correspond to three-parameter Weibull distribution (6). The representative volume of a granular composite, which fills a domain in the form of a cube, is modeled by a set of istropic elastobrittle strain diagrams containing a descending branch are obtained as a result of the mathematical modeling of deformation processes and structural failure to realized a representative volume containing 384 structural elements with different strength and similar elastic constants.Presented at the Ninth International Conference on the Mechanics of Composite Materials, Riga, October, 1995.Perm'State Mechanical University, Russia. Translated From Mekhanika Kompozitnykh Materialov, Vol. 32, No. 6, pp. 808–817, November–December, 1996.     

The Landau-Lifshitz formula and the correspondence principle for semiclassical matrix elements

The semiclassical Landau-Lifshitz formula with pre-exponential factor is derived and its connection with the correspondence principle is traced. Illustrations are given of its use for the Morse potential and the modified Pöschl-Teller potential, and also for a very simple potential with first-order poles.Institute of Chemical Physics at Chernogolovka. USSR Academy of Sciences, Moscow Province. Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 90, No. 2, pp. 218–225, February, 1992.     

Preparation of 3-substituted 2-dimethylamino-5-(3,5,6-trichloro-1,4-benzoquinon-2-yl)thiazolium salts

Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 427–428, March, 1992.     

Biological activity of furan derivatives (review)

Information on the biological activity of furan derivatives for the period 1981–1991 is correlated. The promising character of the study of the biological properties of furan derivatives for the creation of new medicinals is demonstrated.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 291–321, March, 1993.