Physicochemical Properties of Complexes of Zinc Iodide with Pyridine N-Oxides

Polycrystalline 1 : 2 complexes of ZnI₂ with N-oxides of pyridine, picoline, and 2,6-lutidine were studied by IR spectroscopy, dielectrometry, and conductometry. An equilibrium between three solid phases was observed. These phases are characterized by different enthalpies of formation of intermolecular bonds and different mechanism of electronic effect transmission via these bonds. Gas-like thermal molecular motion in one of the phases of the 2,6-lutidine N-oxide complex was observed. Reversible chemical reactions on the surface of the crystalline 3-picoline N-oxide complex are initiated on exposure to an alternating electric field. Two complexes, similarly to the ZnCl₂ complexes, are ionized in the cumulative mode on fast heating from 18-19 to 26-45°C. Partial activation energies of electrical conductivity of different ions were determined for a number of complexes and inorganic salts.     

Radio Absorbing Composite Based on Square Resistive Patches

Technical Physics - Solutions to the diffraction problems are used to calculate the effective permittivity of a composite material consisting of alternating planar arrays of square resistive...     

Inequalities for moments of symmetric polynomial forms in random variables

In the last few years, interest in the properties of distributions of quadratic and polynomial forms in random variables has again grown. Translated fromStatisticheskie Metody Otsenivaniya i Proverki Gipotez, pp. 159–161, Perm, 1993.     

On amorphic <Emphasis Type="Italic">C</Emphasis>-algebras

An amorphic association scheme has the property that any of its fusions also is an association scheme. In this paper, the property of being amorphic is extended to an arbitrary C-algebra, and it is proved that, up to isomorphism, any amorphic C-algebra is determined by the multiset of its diagonal structure constants and an additional integer equal to ±1. It is shown that any amorphic C-algebra with rational structure constants is a fusion of a homogeneous amorphic C-algebra. As a special case, the well-known Ivanov characterization of the intersection numbers of amorphic association schemes is obtained. Bibliography: 13 titles. __________ Translated from Zapiski Nauchnykh Seminarov POMI, Vol. 340, 2006, pp. 87–102.     

The Catenary and Tame Degree in Finitely Generated Commutative Cancellative Monoids

Problems involving chains of irreducible factorizations in atomic integral domains and monoids have been the focus of much recent literature. If S is a commutative cancellative atomic monoid, then the catenary degree of S (denoted c(S)) and the tame degree of S (denoted t(S)) are combinatorial invariants of S which describe the behavior of chains of factorizations. In this note, we describe methods to compute both c(S) and t(S) when M is a finitely generated commutative cancellative monoid.     

Synthesis of fluoro-containing substituted 1,3,5-triazines

Conclusions By the method of acylation-cyclodehydration of imidoylamidines we have prepared 1,3,5-triazines with three different substituents, among them reactive unsaturated and nitrile groups.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 928–933, April, 1989.     

Polynomial isomorphism algorithm for graphs which do not pinch to K3,g

In this paper we construct a polynomial algorithm for verifying the isomorphism of graphs which do not pinch to K_3,g. In the construction we use properties of colored graphs from this class and results of Babai-Luks on canonization of graphs. The class cited contains the class of graphs of genus not exceeding g, and we apply the algorithm constructed to the recognition of isomorphism of graphs of bounded valence. The method given is a generalization of the combinatorial and group-theoretic approach to the isomorphism problem.Translated from Zapiski Nauchnykh Seminarov Leningradskogo Otdeleniya Matematicheskogo Instituta im. V. A. Steklova AN SSSR, Vol. 137, pp. 99–114, 1984.     

Cycloaddition of perfluorovinyl ethers to dienes

Conclusions Cycloaddition of perfluorovinyl ethers to butadiene or piperylene led to 1-vinyl- or 1-propenyl-2-perfluoroalkoxy-2,3,3-trifluorocyclobutanes as mixtures of cis and trans isomers.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 10, pp. 2372–2377, October, 1988.