Multivalued solutions of the spatial problems of nonlinear deformation of thin curvilinear rods

We have developed a finite-element model to study the spatial deformation of elastic rods at large displacements. A numerical algorithm for constructing multivalued nonlinear solutions in the presence of many bifurcation and limit points is formulated. Results of a study of the stability supercritical equilibrium forms of elastic rods, which were supported experimentally, are reported. Chaplygin Siberian Aviation Institute, Novosibirsk 630051. Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 39, No. 2, pp. 141–149, March–April, 1998.     

Analysis of the Potential Energy Surface of 1,3-Dioxane and Its Protonated Form

Russian Journal of Organic Chemistry -     

Synthesis of oxazoles from α,β-unsaturated carbonyl compounds through 2-acylaziridines

Oxidative addition of N-aminophthalimide to benzylideneacetone and chalcones followed by thermolysis of the arising 2-aryl-3-acyl-1-phthalimidoaziridines led to the formation of 2,5-disubstituted oxazoles in an overall yield 30–55%. Electron-donor substituents in the aryl fragment of 2-aryl-3-aroyl-1-phthalimidoaziridines accelerate their conversion into oxazoles, and similar substituents in the aroyl fragment retard this process. The possibility was demonstrated of going over to oxazoles from α,β-unsaturated carbonyl compounds via 2-acyl-1-sulfonylaziridines employing chloramine-B. However ethyl 2 cyanocinnamate reacted with chloramine-B with the rupture of the C=C bond and the formation of N-benzylidene-benzenesulfamide.     

Production of nanocrystalline silicon layers using the plasma enhanced chemical vapor deposition from the gas phase of silicon tetrafluoride

The production of silicon layers using plasma enhanced chemical vapor deposition in the mixture of silicon tetrafluoride and hydrogen is reported. The samples have been analyzed by X-ray diffraction, Raman spectroscopy, and secondary ion mass spectrometry. The phase composition of the layers is nanocrystalline silicon with the crystalline-domain sizes from 3 to 9 nm in dependence of the conditions of the process. The samples are characterized by intense photoluminescence at room temperature.     

Adsorption of sodium phenylanthranylate on gold electrode from aqueous solution

Adsorption of sodium phenylanthranylate on a gold electrode from a borate buffer solution is studied using the methods of ellipsometry and piezo-quartz nanobalance. Statistical evaluation of adequacy between the obtained experimental isotherms and theoretical models is performed using the F-test. It is shown that they are adequately described using the Frumkin and Temkin equation.     

Quantum-chemical Calculation of Standard Redox Potentials of Half-reactions Involving Bismuth Aquacomplexes

The most probable coordination numbers for aquacomplexes of Bi(III), Bi(II), and Bi(I) ions are found in terms of a density functional method (version B3LYP) with allowance for the effect of dielectric medium in the self-consistent reaction field model. Thermodynamic parameters of hydration of these ions are calculated and used for evaluating standard redox potentials of half-reactions involving the ions.