Generalized green operator for an impulsive boundary-value problem with switchings

We establish constructive existence conditions and construct a generalized Green operator for the construction of solutions of a Noetherian linear boundary-value problem for a system of ordinary differential equations with switchings and pulse action in critical and noncritical cases. __________ Translated from Neliniini Kolyvannya, Vol. 10, No. 1, pp. 51–65, January–March, 2007.     

Effect of NO, SO2, and O2 on the conversion of nitrous oxide on iron-containing zeolite catalysts

Conditions were found for facilitation of the conversion of nitrous oxide in the presence of Fe-containing zeolite catalysts by oxidants (NO, SO₂, and O₂). The results were interpreted in the framework of a mechanism involving decomposition of N₂O. The effect of NO_x on the reduction of nitrous oxide by C₃-C₄ alkanes was established. __________ Translated from Teoreticheskaya i éksperimental’naya Khimiya, Vol. 42, No. 4, pp. 241–245, July–August, 2006.     

Activity of Supported Binary Indium–Cobalt Oxide Catalysts in Reduction of Nitrogen(I,II) Oxides with Carbon Monoxide

Russian Journal of Applied Chemistry - Supported binary indium–cobalt oxide catalysts showed high activity in joint reduction of nitrogen(I, II) oxides with carbon monoxide. Their activity is...     

Bounded Solutions of the Nonlinear Lyapunov Equation and Homoclinic Chaos

Ukrainian Mathematical Journal - We study bounded solutions of a nonlinear Lyapunov-type problem in Banach and Hilbert spaces. Necessary and sufficient conditions for the existence of bounded...     

Ultrasonic strength monitoring of carbon-fiber-reinforced plastics based on adhesive prepregs

Results of examinations of VKU-17KE0,1 carbon-fiber-reinforced plastic by the acousto-ultrasonic technique are presented here. The initial control parameters of samples produced with a variant ratio of basic components are determined, and the values of the stress wave factor (SWF) criterion, which is widely used in the United States, are calculated using the peak voltage, weighted ringdown count, and energy integral techniques. The power-spectrum technique proposed at VIAM was also involved in calculation. Correlations of SWF criterion and strength were determined during bending tests of carbon-fiber-reinforced samples.     

Residual stress-strain state of a steel disk under thermal pulsed irradiation

The residual stress-strain state of a disk caused by the action of a laser pulse or an electron beam is investigated within the framework of the dynamic statement of the coupled problem of thermomechanics. The axially symmetric problem is solved numerically using the thermodynamically consistent theory of the inelastic behavior of the material involving the finite-element method and taking into account temperature dependences of physical and mechanical characteristics of the material. The response of the material to thermal irradiation followed by gradual cooling is studied, and the possibility of formation of surface profiles with the use of only thermal treatment is considered. Translated from Matematychni Metody ta Fizyko-Mekhanichni Polya, Vol. 51, No. 1, pp. 157–168, January–March, 2008.     

Solutions of Weakly-Perturbed Linear Systems Bounded on the Entire Axis

We establish conditions under which solutions of weakly-perturbed systems of linear ordinary differential equations bounded on the entire axis R emerge from the point = 0 in the case where the corresponding unperturbed homogeneous linear differential system is exponentially dichotomous on the semiaxes R ₊ and R _–.     

The effect of terminal groups on the structure and properties of oligosilsesquioxanes

The interaction of oligomeric silsesquioxanes, whose organic moieties contain tertiary amino groups and primary and secondary hydroxyl groups, with monoisocyanates and phthalic and acetic anhydrides is employed to synthesize a number of their N-alkyl(aryl)urethane-, carboxyl- and acetyl-terminated derivatives with different degrees of substitution and combinations of the substituents. The obtained derivatives are studied by functional analysis, IR spectroscopy, GPC, DSC, TGA, and wide-angle X-ray scattering. The chemical nature of the incorporated functional groups is found to markedly influence the structure and properties of the synthesized compounds. Depending on the type of substituents and their combination, either the complete amorphization or ordering of the structure of the oligosilsesquioxanes is observed with corresponding changes in their properties.