New Approaches to Synthesizing Electroactive Polymers

The chemical oxidative polymerization of aniline in a heterophase system is studied. In the presence of a solid substrate, the aniline polymerization involves two kinetically and chemically independent processes, namely, the polymerization in the bulk solution and at the substrate surface. The growth of the polyaniline coating at the substrate surface includes three successive processes: interfacial polymerization, adsorptive polymerization, and destruction of the polymer chain. The interfacial oxidative polymerization of diphenylamine and phenothiazine is examined. The yield and chemical structure of polymers is shown to depend on the polymerization conditions.     

Peculiarities of the Electron Structure of Pseudobinary Alloys (GeTe)m–(Sb2Te3)n

Crystallography Reports - The electron band structure of GeTe, Sb2Te3, GeSb2Te4, and Ge2Sb2Te5 compounds has been calculated by the electron density functional method using the WIEN2k software...     

Oxidative bromination of isoprenyl units of butyl rubber with the hydrobromic acid-sodium hypochlorite system

Synthesis of bromo butyl rubber using the hydrobromic acid-sodium hypochlorite system as brominating agent was studied.     

Nucleophilic Replacement of Hydrogen in para-Substituted Nitrobenzenes by Phenylacetonitrile Carbanion

The kinetic relations holding in nucleophilic replacement of hydrogen in para-substituted nitrobenzenes by phenylacetonitrile carbanion suggest a complex reaction mechanism involving two alternative pathways. The direction of the process is determined by the structure of intermediate -complex.     

Calculation of binding energy in negative ions of the alkaline-earth atoms Ca and Sr

The electron binding energy in negative ions of the alkaline-earth atoms Ca and Sr is calculated on the basis of the polarization-potential formalism and relativistic perturbation theory with a zeroth-order model potential. The results improve the data available in the literature for these negative ions. Odessa Hydrometeorological Institute. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 9, pp. 27–31, September, 1996.     

Comparative studies on photo-ionization and electron-impact ionization of peptide derivatives

Photo-ionization (PI) mass spectrometry performed with a monochromatic photon beam was applied to a series of peptide derivatives. PI mass spectra of ten N-acylpeptide methyl esters containing two to four residues of glycine, alanine, valine, leucine, proline, tryptophan, tyrosine, phenylalanine, methionine, carboxymethylcysteine, lysine and ornithine were studied. Comparative analysis of PI (10.2 eV) and electron-impact ionization (EI) (70 eV) mass spectra shows the total number of peaks on PI to be much less than that obtained with EI, especially in the low m/e region (< 250 to 300). At the same time the relative abundance of ‘heavy’ ions, including molecular ions, is much higher in PI. The amino acid fragmentation pattern followed by N-acylpeptide esters in PI was found to be the same as for EI.     

A class of lacunary trigonometric series

It is shown that there exists a sequence of natural numbers {n_k} which does not belong to the class B₂ and which cannot be decomposed into a finite number of lacunary sequences such that: a) if the series converges on a set of positive measure, then the series consisting of the squares of the coefficients converges; b) for each set E of positive measure we can remove from the system a finite number of terms with the result that what is left is a Bessel system in L²(E); and c) if the series converges to zero on a set of positive measure, then each coefficient is zero.Translated from Matematicheskie Zametki, Vol. 14, No. 6, pp. 781–788, December, 1973.In conclusion the author wishes to thank V. F. Emel'yanov for posing the problem and for helping to solve it.