X-ray investigations of modulations in Cs2ZnI4

The X-ray diffractometer patterns of a reciprocal space have been analyzed in the modulated phases of Cs₂ZnI₄ crystals. The character of the atomic displacements in the modulation wave has been established. The temperature behaviour of both a modulation wave vector and amplitude has been determined from the position and intensity of satellite reflections.     

Some reactions of 2-(2-hydroxyhexafluoro)isopropyl-5-methylfuran

The bromination of 2-(2-hydroxyhexafluoro)isopropyl-5-methylfuran at the methyl group and subsequent reaction with nitrogen nucleophiles gave some secondary amines and quaternary salts.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1308–1311, October, 1992.     

Near field diffracted at a dielectric wedge

The integral equations of macroscopic dynamics [2] are used in [1] as the basis of a solution to the problem of the diffraction of a plane electromagnetic wave with a known polarization at a rectangular dielectric wedge. Expressions are given in this paper for the total electromagnetic field both inside a dielectric wedge of arbitrary flare angle and outside the wedge. The method used is the same as in [1].Translated from Zhurnal Prikladnoi Mekhaniki i Tekhnicheskoi Fiziki, No. 4, pp. 174–181, July–August, 1976.     

Correlation of the electrochemical reversibility and resolution of the anode and cathode peaks of the electrode processes of hydroquinone and metol on graphite and platinum

Cyclic and direct voltammetry with linear potential sweep was used to study the potential difference of the anode and cathode peaks for hydroquinone and metol in the cyclic voltammograms (CVA) of their individual solutions on the main factors affecting the reversibility of the electrochemical process on electrodes of a graphite-epoxy composite (GEC), namely, the state of the surface of the indicator electrode, the pH of the buffer solution, and the mode of polarization. The surface state of the GEC electrode was affected by its passivation in air for various periods of time; the reversibility of the electrode process was judged by the difference between the anode and cathode potentials on the CVAs of hydroquinone and metol. A correlation was found between the degree of reversibility and the difference of peak potentials for similar electrode processes of hydroquinone and metol on the GEC electrode and other solid electrodes made of graphite materials and platinum.     

Chemical exchange in KHSeO4 and NH4HSeO4 studied by two-dimensional NMR

The microscopic mechanism of proton transport in partially deuterated potassium hydrogen selenate (KHSe) and in partially deuterated ammonium hydrogen selenate (AHSe) were studied by means of one-dimensional Fourier transform²H nuclear magnetic resonance (NMR), two-dimensional²H NMR and dielectric measurements over a wide temperature range. In both systems, KHSe and AHSe, the slow chemical exchange processes of deuterons between different hydrogen bridges occur. It was established that the rates of exchange between deuteron sites, which are involved in infinite chains of hydrogen bonds, are approximately the same for both crystals. The rates of exchange between these positions and the deuterons in the dimer groups of KHSe are approximately hundred times more slowly. On the basis of our findings, we discuss the models of the microscopic mechanism of hydrogen transport for both substances.     

Steric structure of N-allylphthalimide oxide and thiooxide

Conclusions N-Allylphthalimide oxide and thiooxide exist predominantly in the gauche conformation based on the C-C_ring bond, with a syn orientation of the phthalimide group and heteroatom of the three-membered ring. The phthalimide radical protrudes from the plane of N-C-C_ring by an angle of 60°.Translated from Investiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 664–667, March, 1979.The authors thank A. M. Salikhov for taking the IR spectra of the studied compounds.