Approximating characteristic equations for autonomous systems of differential equations with aftereffect

In this paper we construct approximating polynomial characteristic equations for a linear autonomous system with aftereffect. The procedures for constructing approximating characteristic equations use analytic representations of resolvents of infinitesimal operators and the theory of characteristic determinants and perturbation determinants in a separable Hilbert space.     

Effect of annealing on ESR characteristics of zirconia nanopowders with different impurity compositions

Physics of the Solid State - An ESR study is performed for four groups of zirconia nanopowder samples: nominally pure ZrO2 powders (first group), zirconia samples with Y2O3 and Sc2O3 impurities...     

Synthesis of new mixed-ligand cationic complexes of palladium [(acac)Pd(PPh3)(L)]BF4

Russian Journal of General Chemistry -     

Magnetochemical effects occurring upon treatment of the thin ferromagnetic film surface in an acidic medium

The results from magnetooptical studies of the influence of magnetochemical effects on the surface morphology and local magnetic properties of FeN alloy thin films and thin-film systems that consist of alternating silicon dioxide and FeN layers of submicron thickness, are shown. The dramatic influence of chemical etching on the surface morphology and magnetic characteristics of the investigated samples is revealed.     

Suppression of the spectral selectivity of two-layer phase-relief diffraction structures

Optics and Spectroscopy - The method and results of studying the effect of relief depth on the attainable degree of reducing the spectral selectivity of two-layer diffraction structures based on...     

Specific features in the observation of electron diffraction

Difficulties in the explanation of the interference pattern produced by electron diffraction are discussed. An important role of exciton drops in the formation of interference pattern is noted.     

Stereo- and regioselectivity of the catalytic system MoCl5/SiO2-SnMe4 in the reaction of metathesis and cometathesis of olefins and their functional derivatives

It was shown that the catalytic system MoCl₅/SiO₂-SnMe₄ has almost 100% regioselectivity with respect to olefins. The stereoselectivity of the system is not a function of the length of the -olefin chain, temperature, or addition of functional groups (COOEt, Cl). Addition of pentachlorophenoxy and 8-hydroxyquinolyl ligands significantly reduces the activity of the catalytic system with a slight increase in the stereoselectivity with respect to the cis-isomer.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 1, pp. 168–171, January, 1990.