Diffusion der Gase und Dämpe organischer Verbindungen durch Polymerfolien

Ohne Zusammenfassung     

Structural studies by 1H and 13C DNMR—II°: Alternative protonation sites in carbonyl conjugated chain enamines of the type R1-C1O-C2HC3H-NR2R3. A method of synthesis of disubstituted pyridinium salts

O-Protonation of secondary enamino ketones in TFA or concentrated mineral acids in various solvents is the kinetically favoured course of reaction leading ultimately to stable 2,5- or 3,4-disubstituted pyridinium salts. The mechanism of formation of the salts involves electrophilic attack by the C-3 carbon atom on C-2 or N-nucleophilic centres of the O-protonated molecule.     

Central charges and Lorentz and internal symmetries in massive supersymmetric quantum field theory

The properties of central charges in the framework of the massive supersymmetric quantum field theory related to internal symmetries, Lorentz covariance and locality of the fields are investigated. It is shown that in the presence of z central charges the largest semisimple part of the internal symmetry algebra is a direct sum of z compact symplectic group algebras and possibly an additional term representing the unimodular unitary group algebra. Next it is shown that 4j ? N + K, where j is the highest spin value of the underlying fields, N is the number of spinorial charges and K the number of these spinorial charges which are not linked to other spinorial charges by a central charge. It is further demonstrated that, in general, the central charge can not be redefined in such a way that it is at the same time real and preserves the locality principle. The discussion of the obtained results concludes the paper.     

Iterative least-squares analysis of dynamic n.m.r. spectra. Hindered rotation of the N-nitroso group in N-nitroso-N-cyanomethylmethylamine

Iterative analysis of dynamic n.m.r. (d.n.m.r.) spectra by the least-squares method was applied to the entire proton spectrum of N-nitroso-N-cyanomethylmethylamine and, separately, to the CH₃ and CH₂CN sub-spectra. Resulting differences in the estimated rates of rotation of the NO group are discussed in terms of systematic errors which may be involved in determining spin exchange rates by d.n.m.r. methods. The most probable explanation is that quadrupolar broadening and then unresolved ¹⁴N? ¹H spin–spin splitting may appear on increasing the temperature. Estimated entropies of activation indicate that the methyl sub-spectrum gives more reliable results.     

The surface composition of the gold-palladium binary alloy system

The surface composition of the AuPd alloy system has been determined by Auger electron spectroscopy. Measurements were performed on polished polycrystalline alloy foils. After cleaning, the intensities of the 71 eV and 2024 eV gold Auger transitions, and the intensity of the 330 eV palladium transition were measured, and then converted to atom concentrations in the surface layer. The surfaces of the annealed samples were found to be significantly enriched in gold with respect to the bulk. This result disagrees with the regular solution theory prediction. After extensive sputtering of the AuPd alloys with 1.5 keV Ar⁺ ions, a slight surface enrichment with palladium was found, as predicted by the simple theoretical model for sputtering.     

Adsorption of gas mixtures on heterogeneous surfaces: The integral representation for a monolayer total adsorption isotherm

The authors extended the integral equation for a one-component adsorption isotherm on to n-component adsorption from gaseous mixtures. It appears that the n-component adsorption isotherm on heterogeneous surfaces can be presented as a multiple integral. Two methods were used for evaluation of the surface heterogeneity with regard to a gas mixture. The first method is based on the n-dimensional gaussian energy distribution. The second one concerns the extension of our method for studying adsorption systems of high surface heterogeneity. Two-component adsorption systems have been analyzed in details.     

Probability measures on operator algebras

The problem of linearity of probability measures on hyperfinite factors is studied in Part I. Part II contains the extension of Vital-Hahn-Saks, Egoroff and Lusic theorems for probability measures on von Neumann algebras. These problems have immediate connections with properties of physical states on observable algebras in the sense of Mackey.     

Studies on the Decomposition of Carbon Dioxide in a Low-Temperature Plasma

The decomposition of carbon dioxide was studied in an argon plasma jet, generated by a direct-current arc discharge. The decomposition degree of carbon dioxide was up to 0,4 at an effective energy consumption lower than 1 MJ/mole CO. The efficiency of high-temperature decomposition of carbon dioxide to carbon monoxide and oxygen is essentially dependent both on the quenching intensity of the products, which prevents from the reverse oxidation reaction in the system, as well as on the proper conditions of plasma-substrate mixing.