Nonisomorphic graphs with identical atomic counts of self-returning walks: Isocodal graphs

On the basis of endospectral graphs, we present a graphical method for obtaining pairs of nonisomorphic graphs with identical atomic counts of self-returning walks.     

2,2-diphenyl-1-(trifluoromethanesulphonyl)-hydrazyl

2,2-diphenyl-1-(trifluoromethanesulphonyl)-hydrazyl was prepared by oxidation of the corresponding hydrazine, and is stable in solution. Its ESR spectrum is interpreted in terms of a larger coupling constant for the tricoordinated than for the dicoordinated nitrogen, and of proton coupling constants indicating non-equivalent phenyl groups.     

Ultraviolet absorption spectrum of pyrylium perchlorate

Summary The bathocromic shift observed in the ultraviolet spectra of sym-trimethyl derivatives of benzene, pyridine, pyridinium, and pyrylium is caused in equal measure by the heterocycle and by the substituents.     

Large field renormalization. II. Localization,exponentiation, and bounds for the R operation

In this paper we conclude the discussion of the basic properties and bounds for theR operation. This allows us to complete the proof of the ultraviolet stability of four-dimensional pure gauge field theories, as formulated in Theorem 1.Research supported in part by the National Science Foundation under Grant DMS-86 02207     

Central vertices versus central rings in polycyclic systems

This naive supposition that the central vertex(es) in polycyclic graphs should always belong to central ring(s) was examined for various cases of systems containing condensed (fused) 3-, 4-, 5-, 6- and 7-membered rings, as well as combinations of 5- and 7-membered rings. It was found that this conjecture is a general trend valid in the great majority of cases. However, counterexamples with the smallest number of rings are reported for all types of these systems.     

Electronic Processes and Energy Storage in Inorganic/Organic Nanohybrids

Three types of nanohybridized structures such as organic/dielectric, organic/semiconductor, and organic/graphen-like ones are investigated. The effect of ultrasonic exposure on the material structure and its influence on the dielectric permeability and on the dielectric loss tangent are studied for the first type of nanostructures. The magnetoresistance of a structure at room temperature is studied in the second type of materials. The change of the kinetic parameters of the intercalation process is shown for the third type of nanohybrid structures.