Analysis of oscillations of concentration in bounded binary mixtures taking into account surface effects

We consider a binary mixture bordering a substrate and vacuum and forming a film. The distribution of one of the mixture components is described by the Cahn-Hillard equation with asymmetric boundary conditions taking into account (wetting) processes occurring at the boundary and in surface layers of the film and, probably, the effect of a constant external magnetic field. The parameters of the problem characterize the bulk correlation length, pair interaction intensity in the nearest neighbor approximation at the film boundary, and the renormalized magnetic field acting on the spins in the surface layers of the system. The range of parameters generating oscillations of the concentration over the film thickness is determined. Subranges of parameters generating the preset number of oscillations over the film cross section are indicated. The analytic results are qualitatively confirmed in numerical experiments.     

Research in the imidazole series

It was established that the reaction of 8-theophylline with α-halo ketones gives 8-acylalkylthiotheophyllines or their cyclization products-thiazolo[2,3-f]xanthine derivatives — depending on the conditions used to carry out the reaction and the structure of the halo ketones. Derivatives of two new heterocyclic systemscy-clopentathiazolo[2,3-f]purine and benzothiazolo[2,3-f]purine-were synthesized from 2-bromocyclopentadienone and cyclohexanone. The structure and the conditions for the cyclization of 8-acylalkylthiotheophyllines to three(four)-ring compounds were studied. The structure of the thiazolo[2.3-f]xanthines was proved by reductive desulfuration to 1,3,7-trialkylxanthines.     

Mass specteometric study of adamantane derivatives

Conclusions The characteristic peculiarities of the mass spectra of adamantanes containing two functional groups in the junction positions 1 and 3 were found.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1510–1513, July, 1972.     

Stereochemistry of the complexation of derivatives of tricyclo[4.2.2.05,8] decadiene and related cycloalkenes with AgEu(fod)4

The stereochemical features of the complexation of derivatives of tricyclo[4.2.2.0^{5, 8}]decadiene and related cycloalkenes with AgEu (fod)₄ have been investigated by PMR spectroscopy with silver-lanthanide shift reagents. The bidentate structure of the complexes investigated has been established on the basis of the results of calculations carried out with the use of silver—lanthanide-induced shifts.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 21, No. 6, pp. 736–739, November–December, 1985.We express our thanks to A. S. Koz'min and V. N. Kirin for supplying the samples of compounds 1 and 2.